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Sample records for adequate selenocysteine trna

  1. Tertiary structure of bacterial selenocysteine tRNA.

    Itoh, Yuzuru; Sekine, Shun-ichi; Suetsugu, Shiro; Yokoyama, Shigeyuki

    2013-07-01

    Selenocysteine (Sec) is translationally incorporated into proteins in response to the UGA codon. The tRNA specific to Sec (tRNA(Sec)) is first ligated with serine by seryl-tRNA synthetase (SerRS). In the present study, we determined the 3.1 Å crystal structure of the tRNA(Sec) from the bacterium Aquifex aeolicus, in complex with the heterologous SerRS from the archaeon Methanopyrus kandleri. The bacterial tRNA(Sec) assumes the L-shaped structure, from which the long extra arm protrudes. Although the D-arm conformation and the extra-arm orientation are similar to those of eukaryal/archaeal tRNA(Sec)s, A. aeolicus tRNA(Sec) has unique base triples, G14:C21:U8 and C15:G20a:G48, which occupy the positions corresponding to the U8:A14 and R15:Y48 tertiary base pairs of canonical tRNAs. Methanopyrus kandleri SerRS exhibited serine ligation activity toward A. aeolicus tRNA(Sec) in vitro. The SerRS N-terminal domain interacts with the extra-arm stem and the outer corner of tRNA(Sec). Similar interactions exist in the reported tRNA(Ser) and SerRS complex structure from the bacterium Thermus thermophilus. Although the catalytic C-terminal domain of M. kandleri SerRS lacks interactions with A. aeolicus tRNA(Sec) in the present complex structure, the conformational flexibility of SerRS is likely to allow the CCA terminal region of tRNA(Sec) to enter the SerRS catalytic site. PMID:23649835

  2. Occurrence and functional compatibility within Enterobacteriaceae of a tRNA species which inserts selenocysteine into protein.

    Heider, J; Leinfelder, W; Böck, A

    1989-01-01

    The selC gene from E. coli codes for a tRNA species (tRNA(UCASer] which is aminoacylated with L-serine and which cotranslationally inserts selenocysteine into selenoproteins. By means of Southern hybridization it was demonstrated that this gene occurs in all enterobacteria tested. To assess whether the unique primary and secondary structural features of the E. coli selC gene product are conserved in that of other organisms, the selC homologue from Proteus vulgaris was cloned and sequenced. It...

  3. Selenocysteine Lyase.

    Stadtman, Thressa C

    2004-12-01

    Selenocysteine is a naturally occurring analog of cysteine in which the sulfur atom of the latter is replaced with selenium. This seleno-amino acid occurs as a specific component of various selenoproteins and selenium-dependent enzymes. Incorporation of selenocysteine into these proteins occurs cotranslationally as directed by the UGA codon. For this process, a special tRNA having an anticodon complimentary to UGA, tRNASec, is utilized. In Escherichia coli and related bacteria, this tRNA first is amino acylated with serine, and the seryl-tRNASec is converted to selenocysteyl-tRNASec. The specific incorporation of selenocysteine into proteins directed by the UGA codon depends on the synthesis of selenocysteyl-tRNASec. Included in the selenium delivery protein category are rhodaneses that mobilize selenium from inorganic sources and NIFS-like proteins that liberate elemental selenium from selenocysteine. The NIFS protein from Azotobacter vinelandii was found to serve as an efficient catalyst in vitro for delivery of selenium from free selenocysteine to Escherichia coli selenophosphate synthetase for selenophosphate formation. The widespread distribution of selenocysteine lyase in numerous bacterial species was reported and the bacterial enzymes, like the pig liver enzyme, required pyridoxal phosphate as cofactor. Three NIFS-like genes were isolated from E. coli by Esaki and coworkers and the expressed gene products were isolated and characterized. One of these NIFS-like proteins also exhibited a high preference for selenocysteine over cysteine. M. vannielii, an anaerobic methane-producing organism, that grows in a mineral medium containing formate as sole organic carbon source, synthesizes several specific selenoenzymes required for growth and energy production under these conditions. PMID:26443359

  4. Crystal structure analysis reveals functional flexibility in the selenocysteine-specific tRNA from mouse.

    Oleg M Ganichkin

    Full Text Available BACKGROUND: Selenocysteine tRNAs (tRNA(Sec exhibit a number of unique identity elements that are recognized specifically by proteins of the selenocysteine biosynthetic pathways and decoding machineries. Presently, these identity elements and the mechanisms by which they are interpreted by tRNA(Sec-interacting factors are incompletely understood. METHODOLOGY/PRINCIPAL FINDINGS: We applied rational mutagenesis to obtain well diffracting crystals of murine tRNA(Sec. tRNA(Sec lacking the single-stranded 3'-acceptor end ((ΔGCCARNA(Sec yielded a crystal structure at 2.0 Å resolution. The global structure of (ΔGCCARNA(Sec resembles the structure of human tRNA(Sec determined at 3.1 Å resolution. Structural comparisons revealed flexible regions in tRNA(Sec used for induced fit binding to selenophosphate synthetase. Water molecules located in the present structure were involved in the stabilization of two alternative conformations of the anticodon stem-loop. Modeling of a 2'-O-methylated ribose at position U34 of the anticodon loop as found in a sub-population of tRNA(Secin vivo showed how this modification favors an anticodon loop conformation that is functional during decoding on the ribosome. Soaking of crystals in Mn(2+-containing buffer revealed eight potential divalent metal ion binding sites but the located metal ions did not significantly stabilize specific structural features of tRNA(Sec. CONCLUSIONS/SIGNIFICANCE: We provide the most highly resolved structure of a tRNA(Sec molecule to date and assessed the influence of water molecules and metal ions on the molecule's conformation and dynamics. Our results suggest how conformational changes of tRNA(Sec support its interaction with proteins.

  5. Assessment of reagents for selenocysteine conjugation and the stability of selenocysteine adducts.

    Pedzisa, Lee; Li, Xiuling; Rader, Christoph; Roush, William R

    2016-06-14

    Conventional antibody-drug conjugates (ADCs) are heterogeneous mixtures that have poor pharmacokinetic properties and decreased efficacy relative to homogenous ADCs. Furthermore, ADCs that are maleimide-based often have inadequate circulatory stability, which can result in premature drug release with consequent off-target toxicities. Selenocysteine-modified antibodies have been developed that allow site-specific antibody conjugation, yielding homogeneous ADCs. Herein, we survey several electrophilic functional groups that react with selenocystine with high efficiency. Several of these result in conjugates with stabilities that are superior to maleimide conjugates. Among these, the allenamide functional group reacts with notably high efficiency, leads to conjugates with remarkable stability, and shows exquisite selectivity for selenocysteine conjugation. PMID:27184239

  6. Kinetics of the interaction of translation factor SelB from Escherichia coli with guanosine nucleotides and selenocysteine insertion sequence RNA.

    Thanbichler, M; Bock, A; Goody, R S

    2000-07-01

    The kinetics of the interaction of GTP and GDP with SelB, the specific translation factor for the incorporation of selenocysteine into proteins, have been investigated using the stopped-flow method. Useful signals were obtained using intrinsic (i.e. tryptophan) fluorescence, the fluorescence of methylanthraniloyl derivatives of nucleotides, or fluorescence resonance energy transfer from tryptophan to the methylanthraniloyl group. The affinities of SelB for GTP (K(d) = 0.74 micrometer) and GDP (K(d) = 13.4 micrometer) were considerably lower than those of other translation factors. Of functional significance is the fact that the rate constant for GDP release from its complex with SelB (15 s(-)(1)) is many orders of magnitude larger than for elongation factor Tu, explaining why a GDP/GTP exchange factor is not required for the action of SelB. In contrast, the rate of release of GTP is 2 orders of magnitude slower and not significantly faster than for elongation factor Tu. Using a fluorescently labeled 17-nucleotide RNA minihelix that represents a binding site for the protein and that is part of the fdhF selenocysteine insertion sequence element positioned immediately downstream of the UGA triplet coding for selenocysteine incorporation, the kinetics of the interaction were studied. The high affinity of the interaction (K(d) approximately 1 nm) appeared to be increased even further when selenocysteyl-tRNA(Sec) was bound to SelB, but to be independent of the presence or nature of the guanosine nucleotide at the active site. These results suggest that the affinity of SelB for its RNA binding site is maximized when charged tRNA is bound and decreases to allow dissociation and reading of codons downstream of the selenocysteine codon after selenocysteine peptide bond formation. PMID:10781605

  7. Crystallization and preliminary X-ray crystallographic analysis of Aquifex aeolicus SelA, a bacterial selenocysteine synthase

    The bacterial selenocysteine synthase SelA from Aquifex aeolicus was crystallized and the diffraction resolution was improved by lysine-residue methylation, truncation of N-terminal region (ΔN), and Lys-to-Ala point mutations. Phases were determined by using a selenomethionine-substituted crystal of the ΔN mutant. Selenocysteine (Sec), the 21st amino acid, is synthesized on its specific tRNA (tRNASec) via a multi-step process. In bacteria, tRNASec is ligated first with serine by seryl-tRNA synthetase, which is followed by Ser-to-Sec conversion by Sec synthase (SelA). To elucidate its structure and catalytic mechanism, Aquifex aeolicus SelA was crystallized. Although wild-type SelA crystals diffracted X-rays poorly (to up to 8 Å resolution), the resolution was improved by introducing a quadruple point mutation targeting the loop regions and by methylating the lysine residues, which yielded 3.9 Å resolution diffraction data from a full-length SelA crystal. Truncation of the N-terminal region (ΔN) also improved the resolution. A 3.3 Å resolution data set for phase determination was obtained from a crystal of selenomethionine-substituted Lys-methylated SelA-ΔN

  8. Crystal structure of the full-length bacterial selenocysteine-specific elongation factor SelB.

    Itoh, Yuzuru; Sekine, Shun-Ichi; Yokoyama, Shigeyuki

    2015-10-15

    Selenocysteine (Sec), the 21(st) amino acid in translation, uses its specific tRNA (tRNA(Sec)) to recognize the UGA codon. The Sec-specific elongation factor SelB brings the selenocysteinyl-tRNA(Sec) (Sec-tRNA(Sec)) to the ribosome, dependent on both an in-frame UGA and a Sec-insertion sequence (SECIS) in the mRNA. The bacterial SelB binds mRNA through its C-terminal region, for which crystal structures have been reported. In this study, we determined the crystal structure of the full-length SelB from the bacterium Aquifex aeolicus, in complex with a GTP analog, at 3.2-Å resolution. SelB consists of three EF-Tu-like domains (D1-3), followed by four winged-helix domains (WHD1-4). The spacer region, connecting the N- and C-terminal halves, fixes the position of WHD1 relative to D3. The binding site for the Sec moiety of Sec-tRNA(Sec) is located on the interface between D1 and D2, where a cysteine molecule from the crystallization solution is coordinated by Arg residues, which may mimic Sec binding. The Sec-binding site is smaller and more exposed than the corresponding site of EF-Tu. Complex models of Sec-tRNA(Sec), SECIS RNA, and the 70S ribosome suggest that the unique secondary structure of tRNA(Sec) allows SelB to specifically recognize tRNA(Sec) and characteristically place it at the ribosomal A-site. PMID:26304550

  9. Chlamydomonas reinhardtii selenocysteine tRNA[Ser]Sec

    RAO, MAHADEV; CARLSON, Bradley A.; Novoselov, Sergey V.; Weeks, Donald P.; Vadim N Gladyshev; Dolph L Hatfield

    2003-01-01

    Eukaryotic selenocysteine (Sec) protein insertion machinery was thought to be restricted to animals, but the occurrence of both Sec-containing proteins and the Sec insertion system was recently found in Chlamydomonas reinhardtii, a member of the plant kingdom. Herein, we used RT-PCR to determine the sequence of C. reinhardtii Sec tRNA[Ser]Sec, the first non-animal eukaryotic Sec tRNA[Ser]Sec sequence. Like its animal counterpart, it is 90 nucleotides in length, is aminoacylated with serine by...

  10. Crystallization and preliminary X-ray crystallographic analysis of Aquifex aeolicus SelA, a bacterial selenocysteine synthase.

    Itoh, Yuzuru; Sekine, Shun-ichi; Yokoyama, Shigeyuki

    2012-09-01

    Selenocysteine (Sec), the 21st amino acid, is synthesized on its specific tRNA (tRNA(Sec)) via a multi-step process. In bacteria, tRNA(Sec) is ligated first with serine by seryl-tRNA synthetase, which is followed by Ser-to-Sec conversion by Sec synthase (SelA). To elucidate its structure and catalytic mechanism, Aquifex aeolicus SelA was crystallized. Although wild-type SelA crystals diffracted X-rays poorly (to up to 8 Å resolution), the resolution was improved by introducing a quadruple point mutation targeting the loop regions and by methylating the lysine residues, which yielded 3.9 Å resolution diffraction data from a full-length SelA crystal. Truncation of the N-terminal region (ΔN) also improved the resolution. A 3.3 Å resolution data set for phase determination was obtained from a crystal of selenomethionine-substituted Lys-methylated SelA-ΔN. PMID:22949212

  11. Network of tRNA Gene Sequences

    WEI Fang-ping; LI Sheng; MA Hong-ru

    2008-01-01

    A network of 3719 tRNA gene sequences was constructed using simplest alignment. Its topology, degree distribution and clustering coefficient were studied. The behaviors of the network shift from fluctuated distribution to scale-free distribution when the similarity degree of the tRNA gene sequences increases. The tRNA gene sequences with the same anticodon identity are more self-organized than those with different anticodon identities and form local clusters in the network. Some vertices of the local cluster have a high connection with other local clusters, and the probable reason was given. Moreover, a network constructed by the same number of random tRNA sequences was used to make comparisons. The relationships between the properties of the tRNA similarity network and the characters of tRNA evolutionary history were discussed.

  12. Dimer-dimer interaction of the bacterial selenocysteine synthase SelA promotes functional active-site formation and catalytic specificity.

    Itoh, Yuzuru; Bröcker, Markus J; Sekine, Shun-ichi; Söll, Dieter; Yokoyama, Shigeyuki

    2014-04-17

    The 21st amino acid, selenocysteine (Sec), is incorporated translationally into proteins and is synthesized on its specific tRNA (tRNA(Sec)). In Bacteria, the selenocysteine synthase SelA converts Ser-tRNA(Sec), formed by seryl-tRNA synthetase, to Sec-tRNA(Sec). SelA, a member of the fold-type-I pyridoxal 5'-phosphate-dependent enzyme superfamily, has an exceptional homodecameric quaternary structure with a molecular mass of about 500kDa. Our previously determined crystal structures of Aquifex aeolicus SelA complexed with tRNA(Sec) revealed that the ring-shaped decamer is composed of pentamerized SelA dimers, with two SelA dimers arranged to collaboratively interact with one Ser-tRNA(Sec). The SelA catalytic site is close to the dimer-dimer interface, but the significance of the dimer pentamerization in the catalytic site formation remained elusive. In the present study, we examined the quaternary interactions and demonstrated their importance for SelA activity by systematic mutagenesis. Furthermore, we determined the crystal structures of "depentamerized" SelA variants with mutations at the dimer-dimer interface that prevent pentamerization. These dimeric SelA variants formed a distorted and inactivated catalytic site and confirmed that the pentamer interactions are essential for productive catalytic site formation. Intriguingly, the conformation of the non-functional active site of dimeric SelA shares structural features with other fold-type-I pyridoxal 5'-phosphate-dependent enzymes with native dimer or tetramer (dimer-of-dimers) quaternary structures. PMID:24456689

  13. Selenium utilization in thioredoxin and catalytic advantage provided by selenocysteine

    Thioredoxin (Trx) is a major thiol-disulfide reductase that plays a role in many biological processes, including DNA replication and redox signaling. Although selenocysteine (Sec)-containing Trxs have been identified in certain bacteria, their enzymatic properties have not been characterized. In this study, we expressed a selenoprotein Trx from Treponema denticola, an oral spirochete, in Escherichia coli and characterized this selenoenzyme and its natural cysteine (Cys) homologue using E. coli Trx1 as a positive control. 75Se metabolic labeling and mutation analyses showed that the SECIS (Sec insertion sequence) of T. denticola selenoprotein Trx is functional in the E. coli Sec insertion system with specific selenium incorporation into the Sec residue. The selenoprotein Trx exhibited approximately 10-fold higher catalytic activity than the Sec-to-Cys version and natural Cys homologue and E. coli Trx1, suggesting that Sec confers higher catalytic activity on this thiol-disulfide reductase. Kinetic analysis also showed that the selenoprotein Trx had a 30-fold higher Km than Cys-containing homologues, suggesting that this selenoenzyme is adapted to work efficiently with high concentrations of substrate. Collectively, the results of this study support the hypothesis that selenium utilization in oxidoreductase systems is primarily due to the catalytic advantage provided by the rare amino acid, Sec. - Highlights: • The first characterization of a selenoprotein Trx is presented. • The selenoenzyme Trx exhibits 10-fold higher catalytic activity than Cys homologues. • Se utilization in Trx is primarily due to the catalytic advantage provided by Sec residue

  14. Selenium utilization in thioredoxin and catalytic advantage provided by selenocysteine

    Kim, Moon-Jung [Department of Biochemistry and Molecular Biology, Yeungnam University College of Medicine, Daegu 705-717 (Korea, Republic of); Lee, Byung Cheon [Division of Genetics, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Division of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Hwang, Kwang Yeon [Division of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Gladyshev, Vadim N. [Division of Genetics, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Kim, Hwa-Young, E-mail: hykim@ynu.ac.kr [Department of Biochemistry and Molecular Biology, Yeungnam University College of Medicine, Daegu 705-717 (Korea, Republic of)

    2015-06-12

    Thioredoxin (Trx) is a major thiol-disulfide reductase that plays a role in many biological processes, including DNA replication and redox signaling. Although selenocysteine (Sec)-containing Trxs have been identified in certain bacteria, their enzymatic properties have not been characterized. In this study, we expressed a selenoprotein Trx from Treponema denticola, an oral spirochete, in Escherichia coli and characterized this selenoenzyme and its natural cysteine (Cys) homologue using E. coli Trx1 as a positive control. {sup 75}Se metabolic labeling and mutation analyses showed that the SECIS (Sec insertion sequence) of T. denticola selenoprotein Trx is functional in the E. coli Sec insertion system with specific selenium incorporation into the Sec residue. The selenoprotein Trx exhibited approximately 10-fold higher catalytic activity than the Sec-to-Cys version and natural Cys homologue and E. coli Trx1, suggesting that Sec confers higher catalytic activity on this thiol-disulfide reductase. Kinetic analysis also showed that the selenoprotein Trx had a 30-fold higher K{sub m} than Cys-containing homologues, suggesting that this selenoenzyme is adapted to work efficiently with high concentrations of substrate. Collectively, the results of this study support the hypothesis that selenium utilization in oxidoreductase systems is primarily due to the catalytic advantage provided by the rare amino acid, Sec. - Highlights: • The first characterization of a selenoprotein Trx is presented. • The selenoenzyme Trx exhibits 10-fold higher catalytic activity than Cys homologues. • Se utilization in Trx is primarily due to the catalytic advantage provided by Sec residue.

  15. Disrupted tRNA Genes and tRNA Fragments: A Perspective on tRNA Gene Evolution

    Akio Kanai

    2015-01-01

    Full Text Available Transfer RNAs (tRNAs are small non-coding RNAs with lengths of approximately 70–100 nt. They are directly involved in protein synthesis by carrying amino acids to the ribosome. In this sense, tRNAs are key molecules that connect the RNA world and the protein world. Thus, study of the evolution of tRNA molecules may reveal the processes that led to the establishment of the central dogma: genetic information flows from DNA to RNA to protein. Thanks to the development of DNA sequencers in this century, we have determined a huge number of nucleotide sequences from complete genomes as well as from transcriptomes in many species. Recent analyses of these large data sets have shown that particular tRNA genes, especially in Archaea, are disrupted in unique ways: some tRNA genes contain multiple introns and some are split genes. Even tRNA molecules themselves are fragmented post-transcriptionally in many species. These fragmented small RNAs are known as tRNA-derived fragments (tRFs. In this review, I summarize the progress of research into the disrupted tRNA genes and the tRFs, and propose a possible model for the molecular evolution of tRNAs based on the concept of the combination of fragmented tRNA halves.

  16. Disrupted tRNA Genes and tRNA Fragments: A Perspective on tRNA Gene Evolution.

    Kanai, Akio

    2015-01-01

    Transfer RNAs (tRNAs) are small non-coding RNAs with lengths of approximately 70-100 nt. They are directly involved in protein synthesis by carrying amino acids to the ribosome. In this sense, tRNAs are key molecules that connect the RNA world and the protein world. Thus, study of the evolution of tRNA molecules may reveal the processes that led to the establishment of the central dogma: genetic information flows from DNA to RNA to protein. Thanks to the development of DNA sequencers in this century, we have determined a huge number of nucleotide sequences from complete genomes as well as from transcriptomes in many species. Recent analyses of these large data sets have shown that particular tRNA genes, especially in Archaea, are disrupted in unique ways: some tRNA genes contain multiple introns and some are split genes. Even tRNA molecules themselves are fragmented post-transcriptionally in many species. These fragmented small RNAs are known as tRNA-derived fragments (tRFs). In this review, I summarize the progress of research into the disrupted tRNA genes and the tRFs, and propose a possible model for the molecular evolution of tRNAs based on the concept of the combination of fragmented tRNA halves. PMID:25629271

  17. Making sense of nonsense: the evolution of selenocysteine usage in proteins

    Copeland, Paul R.

    2005-01-01

    A recent analysis of sequences derived from organisms in the Sargasso Sea has revealed a surprisingly different set of selenium-containing proteins than that previously found in sequenced genomes and suggests that selenocysteine utilization has been lost by many groups of organisms during evolution.

  18. Nucleotide sequence of a spinach chloroplast valine tRNA.

    Sprouse, H M; Kashdan, M; Otis, L; Dudock, B

    1981-01-01

    The nucleotide sequence of a spinach chloroplast valine tRNA (sp. chl. tRNA Val) has been determined. This tRNA shows essentially equal homology to prokaryotic valine tRNAs (58-65% homology) and to the mitochondrial valine tRNAs of lower eukaryotes (yeast and N. crassa, 61-62% homology). Sp. chl. tRNA Val shows distinctly lower homology to mouse mitochondrial valine tRNA (53% homology) and to eukaryotic cytoplasmic valine tRNAs (47-53% homology). Sp. chl. tRNA Val, like all other chloroplast ...

  19. tRNA creation by hairpin duplication.

    Widmann, Jeremy; Di Giulio, Massimo; Yarus, Michael; Knight, Rob

    2005-10-01

    Many studies have suggested that the modern cloverleaf structure of tRNA may have arisen through duplication of a primordial hairpin, but the timing of this duplication event has been unclear. Here we measure the level of sequence identity between the two halves of each of a large sample of tRNAs and compare this level to that of chimeric tRNAs constructed either within or between groups defined by phylogeny and/or specificity. We find that actual tRNAs have significantly more matches between the two halves than do random sequences that can form the tRNA structure, but there is no difference in the average level of matching between the two halves of an individual tRNA and the average level of matching between the two halves of the chimeric tRNAs in any of the sets we constructed. These results support the hypothesis that the modern tRNA cloverleaf arose from a single hairpin duplication prior to the divergence of modern tRNA specificities and the three domains of life. PMID:16155749

  20. Roles of Trm9- and ALKBH8-like proteins in the formation of modified wobble uridines in Arabidopsis tRNA

    Leihne, Vibeke; Kirpekar, Finn; Vågbø, Cathrine B;

    2011-01-01

    Uridine at the wobble position of tRNA is usually modified, and modification is required for accurate and efficient protein translation. In eukaryotes, wobble uridines are modified into 5-methoxycarbonylmethyluridine (mcm(5)U), 5-carbamoylmethyluridine (ncm(5)U) or derivatives thereof. Here, we...... activity of AtTRM9 depends on either one of two closely related proteins, AtTRM112a and AtTRM112b. Moreover, we demonstrate that AT1G36310, denoted AtALKBH8, is required for hydroxylation of mcm(5)U to (S)-mchm(5)U in tRNA(Gly)(UCC), and has a function similar to the mammalian dioxygenase ALKBH8......(5)U- and mcm(5)Um-containing forms of the selenocysteine-specific tRNA(Sec) in mammals reflects an important regulatory process. The present study reveals a role in for several hitherto uncharacterized Arabidopsis proteins in the formation of modified wobble uridines....

  1. Selenium induced selenocysteine methyltransferase gene expression and antioxidant enzyme activities in Astragalus chrysochlorus

    Çakir, Özgür; Turgut-Kara, Neslihan; Ari, Şule

    2016-01-01

    Astragalus sp. are used in folk medicine because of their biological activities and are known for the ability to accumulate high levels of selenium (Se). The purpose of this study was to explore gene expression of selenocysteine methyltransferase (SMT), responsible for forming MeSeCys, and activities of ascorbate peroxidase (APX), peroxidase (POX), catalase (CAT) and glutathione reductase (GR) enzymes in callus tissues of Astragalus chrysochlorus growing in different Se-containing media. Quan...

  2. Internally Stabilized Selenocysteine Derivatives: Syntheses, $^7^7$Se NMR and Biomimetic Studies

    Phadnis, Prasad P; Mugesh, G.

    2005-01-01

    Selenocystine $([Sec]_2)$ and aryl-substituted selenocysteine (Sec) derivatives are synthesized, starting from commercially available amino acid L-serine. These compounds are characterized by a number of analytical techniques such as NMR $(^1H, ^1^3C and ^7^7Se)$ and TOF mass spectroscopy. This study reveals that the introduction of amino/imino substituents capable of interacting with selenium may stabilize the Sec derivatives. This study further suggests that the oxidation-elimination reacti...

  3. Selenocysteine containing analogues of Atx1-based peptides protect cells from copper ion toxicity.

    Shoshan, Michal S; Lehman, Yonat; Goch, Wojciech; Bal, Wojciech; Tshuva, Edit Y; Metanis, Norman

    2016-08-01

    Seleno-substituted model peptides of copper metallochaperone proteins were analyzed for the metal affinity and in vitro anti-oxidative reactivity. An acyclic MTCXXC (X is any amino acid) reference peptide previously analyzed as a potent inhibitor of ROS production underwent substitution of the cysteine residues with selenocysteine to give two singly substituted derivatives C3U and C6U and the doubly substituted analogue C3U/C6U. Presumably due to the softer nature of Se vs. S, all selenocysteine containing peptides demonstrated high affinity to Cu(i), higher than that of the reference peptide, and in the same order of magnitude as that measured for the native protein, Atox1. A stronger impact of residue 3 confirmed previous findings on its more dominant role in metal coordination. In vitro studies on the HT-29 human colon cancer cell line, MEF mice embryonic fibroblasts, and MEF with the knocked-out Atox1 gene (Atox1-/-) consistently identified C3U/C6U as the most potent inhibitor of ROS cellular production based on the 2',7'-dichlorodihydrofluorescin diacetate (H2DCF-DA) assay, also in comparison with known drugs employed in the clinic for Wilson's disease. The selenocysteine containing peptides are thus promising drug candidates for chelation therapy of Wilson's disease and related conditions relevant to excessive copper levels. PMID:27349676

  4. Purification and characterization of selenocysteine beta-lyase from Citrobacter freundii

    The purification and characterization of bacterial selenocysteine beta-lyase, an enzyme which specifically catalyzes the cleavage of L-selenocysteine to L-alanine and Se0, are presented. The enzyme, purified to near homogeneity from Citrobacter freundii, is monomeric with a molecular weight of ca. 64,000 and contains 1 mol of pyridoxal 5'-phosphate as a cofactor per mol of enzyme. L-Selenocysteine is the sole substrate. L-Cysteine is a competitive inhibitor of the enzyme. The enzyme also catalyzes the alpha, beta elimination of beta-chloro-L-alanine to form NH3, pyruvate, and Cl- and is irreversibly inactivated during the reaction. The physicochemical properties, e.g., amino acid composition and subunit structure, of the bacterial enzyme are fairly different from those of the pig liver enzyme. However, the catalytic properties of both enzymes, e.g., substrate specificity and inactivation by the substrate or a mechanism-based inactivator, beta-chloro-L-alanine, are very similar

  5. Purification and characterization of selenocysteine beta-lyase from Citrobacter freundii

    Chocat, P.; Esaki, N.; Tanizawa, K.; Nakamura, K.; Tanaka, H.; Soda, K.

    1985-08-01

    The purification and characterization of bacterial selenocysteine beta-lyase, an enzyme which specifically catalyzes the cleavage of L-selenocysteine to L-alanine and Se0, are presented. The enzyme, purified to near homogeneity from Citrobacter freundii, is monomeric with a molecular weight of ca. 64,000 and contains 1 mol of pyridoxal 5'-phosphate as a cofactor per mol of enzyme. L-Selenocysteine is the sole substrate. L-Cysteine is a competitive inhibitor of the enzyme. The enzyme also catalyzes the alpha, beta elimination of beta-chloro-L-alanine to form NH3, pyruvate, and Cl- and is irreversibly inactivated during the reaction. The physicochemical properties, e.g., amino acid composition and subunit structure, of the bacterial enzyme are fairly different from those of the pig liver enzyme. However, the catalytic properties of both enzymes, e.g., substrate specificity and inactivation by the substrate or a mechanism-based inactivator, beta-chloro-L-alanine, are very similar.

  6. tRNA Biology in Mitochondria

    Thalia Salinas-Giegé

    2015-02-01

    Full Text Available Mitochondria are the powerhouses of eukaryotic cells. They are considered as semi-autonomous because they have retained genomes inherited from their prokaryotic ancestor and host fully functional gene expression machineries. These organelles have attracted considerable attention because they combine bacterial-like traits with novel features that evolved in the host cell. Among them, mitochondria use many specific pathways to obtain complete and functional sets of tRNAs as required for translation. In some instances, tRNA genes have been partially or entirely transferred to the nucleus and mitochondria require precise import systems to attain their pool of tRNAs. Still, tRNA genes have also often been maintained in mitochondria. Their genetic arrangement is more diverse than previously envisaged. The expression and maturation of mitochondrial tRNAs often use specific enzymes that evolved during eukaryote history. For instance many mitochondria use a eukaryote-specific RNase P enzyme devoid of RNA. The structure itself of mitochondrial encoded tRNAs is also very diverse, as e.g., in Metazoan, where tRNAs often show non canonical or truncated structures. As a result, the translational machinery in mitochondria evolved adapted strategies to accommodate the peculiarities of these tRNAs, in particular simplified identity rules for their aminoacylation. Here, we review the specific features of tRNA biology in mitochondria from model species representing the major eukaryotic groups, with an emphasis on recent research on tRNA import, maturation and aminoacylation.

  7. Kinetic Analysis of tRNA Methylfransferases

    Hou, Ya-Ming; Masuda, Isao

    2016-01-01

    Transfer RNA (tRNA) molecules contain many chemical modifications that are introduced after transcription. A major form of these modifications is methyl transfer to bases and backbone groups, using S-adenosyl methionine (AdoMet) as the methyl donor. Each methylation confers a specific advantage to tRNA in structure or in function. A remarkable methylation is to the G37 base on the 3' side of the anticodon to generate m1G37-tRNA, which suppresses frameshift errors during protein synthesis and is therefore essential for cell growth in all three domains of life. This methylation is catalyzed by TrmD in bacteria and by Trm5 in eukaryotes and archaea. Although TrmD and Trm5 catalyze the same methylation reaction, kinetic analysis reveal that these two enzymes are unrelated to each other and are distinct in their reaction mechanism. This chapter summarizes the kinetic assays that are used to reveal the distinction between TrmD and Trm5. Three types of assays are described, the steady-state, the pre-steady-state, and the single turnover assays, which collectively provide the basis for mechanistic investigation of AdoMet-dependent methyl transfer reactions. PMID:26253967

  8. RNA versatility governs tRNA function: Why tRNA flexibility is essential beyond the translation cycle.

    Kuhn, Claus-D

    2016-05-01

    tRNAs undergo multiple conformational changes during the translation cycle that are required for tRNA translocation and proper communication between the ribosome and translation factors. Recent structural data on how destabilized tRNAs utilize the CCA-adding enzyme to proofread themselves put a spotlight on tRNA flexibility beyond the translation cycle. In analogy to tRNA surveillance, this review finds that other processes also exploit versatile tRNA folding to achieve, amongst others, specific aminoacylation, translational regulation by riboswitches or a block of bacterial translation. tRNA flexibility is thereby not restricted to the hinges utilized during translation. In contrast, the flexibility of tRNA is distributed all over its L-shape and is actively exploited by the tRNA-interacting partners to discriminate one tRNA from another. Since the majority of tRNA modifications also modulate tRNA flexibility it seems that cells devote enormous resources to tightly sense and regulate tRNA structure. This is likely required for error-free protein synthesis. PMID:26990636

  9. Lands adequation in Antioquia Department

    The Colombian government programs concerning land management and adequation began since the fifties. When basic frameworks for irrigating, flood control and drainage were initially developed. Several entities have made huge investments in land adequation, that lead to the improvement of national agriculture in plain regions such as Tolima, Boyaca, Magdalena and Valle del Cauca. During the same period the region of Antioquia did not benefit from the projects, mainly due to the lack of government policies concerning land adequation. Finally, in 1983 the Himat launched the small irrigation national program, which gave solutions for water management in several countryside regions of Antioquia. Twenty-nine small water districts are now operating accounting for 3.759 ha which cover 1.510 households. Now days, thanks to the presence of more accurate policies, is the right time to improve irrigation, flood control and drainage towards to a substantial improvement in the Antioquia agricultural sector, that allows it to overcome the challenges of the next millennium. A project called Antioquia nos une 1998-2000 addresses the importance of promoting the right agricultural structure that ensures agricultural mechanization for sustainability and irrigation. On the other hand, it determines the main resources needed to promote the initiative and points out the importance of distributing them in the basis of the needs and problems of the communities

  10. Structural Insights into tRNA Dynamics on the Ribosome

    Xabier Agirrezabala

    2015-04-01

    Full Text Available High-resolution structures at different stages, as well as biochemical, single molecule and computational approaches have highlighted the elasticity of tRNA molecules when bound to the ribosome. It is well acknowledged that the inherent structural flexibility of the tRNA lies at the heart of the protein synthesis process. Here, we review the recent advances and describe considerations that the conformational changes of the tRNA molecules offer about the mechanisms grounded in translation.

  11. Structural Insights into tRNA Dynamics on the Ribosome.

    Agirrezabala, Xabier; Valle, Mikel

    2015-01-01

    High-resolution structures at different stages, as well as biochemical, single molecule and computational approaches have highlighted the elasticity of tRNA molecules when bound to the ribosome. It is well acknowledged that the inherent structural flexibility of the tRNA lies at the heart of the protein synthesis process. Here, we review the recent advances and describe considerations that the conformational changes of the tRNA molecules offer about the mechanisms grounded in translation. PMID:25941930

  12. Structural Insights into tRNA Dynamics on the Ribosome

    Xabier Agirrezabala; Mikel Valle

    2015-01-01

    High-resolution structures at different stages, as well as biochemical, single molecule and computational approaches have highlighted the elasticity of tRNA molecules when bound to the ribosome. It is well acknowledged that the inherent structural flexibility of the tRNA lies at the heart of the protein synthesis process. Here, we review the recent advances and describe considerations that the conformational changes of the tRNA molecules offer about the mechanisms grounded in translation.

  13. Mitochondrial tRNA gene translocations in highly eusocial bees

    Daniela Silvestre; Maria Cristina Arias

    2006-01-01

    Mitochondrial gene rearrangement events, especially involving tRNA genes, have been described more frequently as more complete mitochondrial genome sequences are becoming available. In the present work, we analyzed mitochondrial tRNA gene rearrangements between two bee species belonging to the tribes Apini and Meliponini within the "corbiculate Apidae". Eleven tRNA genes are in different genome positions or strands. The molecular events responsible for each translocation are explained. Consid...

  14. Nucleolar Clustering of Dispersed tRNA Genes

    Thompson, Martin; Haeusler, Rebecca A.; Good, Paul D.; Engelke, David R.

    2003-01-01

    Early transfer RNA (tRNA) processing events in Saccharomyces cerevisiae are coordinated in the nucleolus, the site normally associated with ribosome biosynthesis. To test whether spatial organization of the tRNA pathway begins with nucleolar clustering of the genes, we have probed the subnuclear location of five different tRNA gene families. The results show that tRNA genes, though dispersed in the linear genome, colocalize with 5S ribosomal DNA and U14 small nucleolar RNA at the nucleolus. N...

  15. Structural basis for early-onset neurological disorders caused by mutations in human selenocysteine synthase.

    Puppala, Anupama K; French, Rachel L; Matthies, Doreen; Baxa, Ulrich; Subramaniam, Sriram; Simonović, Miljan

    2016-01-01

    Selenocysteine synthase (SepSecS) catalyzes the terminal reaction of selenocysteine, and is vital for human selenoproteome integrity. Autosomal recessive inheritance of mutations in SepSecS-Ala239Thr, Thr325Ser, Tyr334Cys and Tyr429*-induced severe, early-onset, neurological disorders in distinct human populations. Although harboring different mutant alleles, patients presented remarkably similar phenotypes typified by cerebellar and cerebral atrophy, seizures, irritability, ataxia, and extreme spasticity. However, it has remained unclear how these genetic alterations affected the structure of SepSecS and subsequently elicited the development of a neurological pathology. Herein, our biophysical and structural characterization demonstrates that, with the exception of Tyr429*, pathogenic mutations decrease protein stability and trigger protein misfolding. We propose that the reduced stability and increased propensity towards misfolding are the main causes for the loss of SepSecS activity in afflicted patients, and that these factors contribute to disease progression. We also suggest that misfolding of enzymes regulating protein synthesis should be considered in the diagnosis and study of childhood neurological disorders. PMID:27576344

  16. Crystallization and preliminary X-ray crystallographic analysis of Aquifex aeolicus SelA, a bacterial selenocysteine synthase

    Itoh, Yuzuru; Sekine, Shun-ichi; Yokoyama, Shigeyuki

    2012-01-01

    The bacterial selenocysteine synthase SelA from Aquifex aeolicus was crystallized and the diffraction resolution was improved by lysine-residue methylation, truncation of N-terminal region (ΔN), and Lys-to-Ala point mutations. Phases were determined by using a selenomethionine-substituted crystal of the ΔN mutant.

  17. HUMAN MITOCHONDRIAL tRNA MUTATIONS IN MATERNALLY INHERITED DEAFNESS

    ZHENG Jing; GONG Sha-sha; TANG Xiao-wen; ZHU Yi; GUAN Min-xin

    2013-01-01

    Mutations in mitochondrial tRNA genes have been shown to be associated with maternally inherited syn-dromic and non-syndromic deafness. Among those, mutations such as tRNALeu(UUR) 3243A>G associated with syndromic deafness are often present in heteroplasmy, and the non-syndromic deafness-associated tRNA mu-tations including tRNASer(UCN) 7445A>G are often in homoplasmy or in high levels of heteroplasmy. These tRNA mutations are the primary factors underlying the development of hearing loss. However, other tRNA mutations such as tRNAThr 15927G>A and tRNASer(UCN) 7444G>A are insufficient to produce a deafness phe-notype, but always act in synergy with the primary mitochondrial DNA mutations, and can modulate their phenotypic manifestation. These tRNA mutations may alter the structure and function of the corresponding mitochondrial tRNAs and cause failures in tRNAs metabolism. Thereby, the impairment of mitochondrial protein synthesis and subsequent defects in respiration caused by these tRNA mutations, results in mitochon-drial dysfunctions and eventually leads to the development of hearing loss. Here, we summarized the deaf-ness-associated mitochondrial tRNA mutations and discussed the pathophysiology of these mitochondrial tRNA mutations, and we hope these data will provide a foundation for the early diagnosis, management, and treatment of maternally inherited deafness.

  18. Nucleotide sequence of a human tRNA gene heterocluster

    Leucine tRNA from bovine liver was used as a hybridization probe to screen a human gene library harbored in Charon-4A of bacteriophage lambda. The human DNA inserts from plaque-pure clones were characterized by restriction endonuclease mapping and Southern hybridization techniques, using both [3'-32P]-labeled bovine liver leucine tRNA and total tRNA as hybridization probes. An 8-kb Hind III fragment of one of these γ-clones was subcloned into the Hind III site of pBR322. Subsequent fine restriction mapping and DNA sequence analysis of this plasmid DNA indicated the presence of four tRNA genes within the 8-kb DNA fragment. A leucine tRNA gene with an anticodon of AAG and a proline tRNA gene with an anticodon of AGG are in a 1.6-kb subfragment. A threonine tRNA gene with an anticodon of UGU and an as yet unidentified tRNA gene are located in a 1.1-kb subfragment. These two different subfragments are separated by 2.8 kb. The coding regions of the three sequenced genes contain characteristic internal split promoter sequences and do not have intervening sequences. The 3'-flanking region of these three genes have typical RNA polymerase III termination sites of at least four consecutive T residues

  19. Molecular basis of dihydrouridine formation on tRNA

    Yu, Futao; Tanaka, Yoshikazu; Yamashita, Keitaro; Suzuki, Takeo; Nakamura, Akiyoshi; Hirano, Nagisa; Suzuki, Tsutomu; Yao, Min; Tanaka, Isao

    2011-01-01

    Dihydrouridine (D) is a highly conserved modified base found in tRNAs from all domains of life. Dihydrouridine synthase (Dus) catalyzes the D formation of tRNA through reduction of uracil base with flavin mononucleotide (FMN) as a cofactor. Here, we report the crystal structures of Thermus thermophilus Dus (TthDus), which is responsible for D formation at positions 20 and 20a, in complex with tRNA and with a short fragment of tRNA (D-loop). Dus interacts extensively with the D-arm and recogni...

  20. Free left and right adequate semigroups

    Kambites, Mark

    2009-01-01

    Recent research of the author has given an explicit geometric description of free (two-sided) adequate semigroups and monoids, as sets of labelled directed trees under a natural combinatorial multiplication. In this paper we show that there are natural embeddings of each free right adequate and free left adequate semigroup or monoid into the corresponding free adequate semigroup or monoid. The corresponding classes of trees are easily described and the resulting geometric representation of fr...

  1. Mutations in the selenocysteine insertion sequence–binding protein 2 gene lead to a multisystem selenoprotein deficiency disorder in humans

    Schoenmakers, Erik; Agostini, Maura; Mitchell, Catherine; Schoenmakers, Nadia; Papp, Laura; Rajanayagam, Odelia; Padidela, Raja; Ceron-Gutierrez, Lourdes; Doffinger, Rainer; Prevosto, Claudia; Luan, Jian’an; Montano, Sergio; Lu, Jun; Castanet, Mireille; Clemons, Nick

    2010-01-01

    Selenium, a trace element that is fundamental to human health, is incorporated into some proteins as selenocysteine (Sec), generating a family of selenoproteins. Sec incorporation is mediated by a multiprotein complex that includes Sec insertion sequence–binding protein 2 (SECISBP2; also known as SBP2). Here, we describe subjects with compound heterozygous defects in the SECISBP2 gene. These individuals have reduced synthesis of most of the 25 known human selenoproteins, resulting in a comple...

  2. Identity determinants of E. coli tryptophan tRNA.

    Himeno, H; T. Hasegawa; Asahara, H; Tamura, K.; Shimizu, M

    1991-01-01

    The first base pair of the acceptor stem A1-U72 and the discriminator base G73, as well as the anticodon nucleotides, characterize the tryptophan tRNA in E. coli. To determine the contribution of these nucleotides to the tryptophan acceptor activity, various transcripts of E. coli tryptophan tRNA mutants were constructed. Substitutions of the discriminator base G73, which is conserved within prokaryotic tryptophan tRNAs, impaired aminoacylation with tryptophan. Substitutions of other purine-p...

  3. Origins and Early Evolution of the tRNA Molecule

    Koji Tamura

    2015-12-01

    Full Text Available Modern transfer RNAs (tRNAs are composed of ~76 nucleotides and play an important role as “adaptor” molecules that mediate the translation of information from messenger RNAs (mRNAs. Many studies suggest that the contemporary full-length tRNA was formed by the ligation of half-sized hairpin-like RNAs. A minihelix (a coaxial stack of the acceptor stem on the T-stem of tRNA can function both in aminoacylation by aminoacyl tRNA synthetases and in peptide bond formation on the ribosome, indicating that it may be a vestige of the ancestral tRNA. The universal CCA-3′ terminus of tRNA is also a typical characteristic of the molecule. “Why CCA?” is the fundamental unanswered question, but several findings give a comprehensive picture of its origin. Here, the origins and early evolution of tRNA are discussed in terms of various perspectives, including nucleotide ligation, chiral selectivity of amino acids, genetic code evolution, and the organization of the ribosomal peptidyl transferase center (PTC. The proto-tRNA molecules may have evolved not only as adaptors but also as contributors to the composition of the ribosome.

  4. Alternative transcripts and 3'UTR elements govern the incorporation of selenocysteine into selenoprotein S.

    Jodi L Bubenik

    Full Text Available Selenoprotein S (SelS is a 189 amino acid trans-membrane protein that plays an important yet undefined role in the unfolded protein response. It has been proposed that SelS may function as a reductase, with the penultimate selenocysteine (Sec(188 residue participating in a selenosulfide bond with cysteine (Cys(174. Cotranslational incorporation of Sec into SelS depends on the recoding of the UGA codon, which requires a Selenocysteine Insertion Sequence (SECIS element in the 3'UTR of the transcript. Here we identify multiple mechanisms that regulate the expression of SelS. The human SelS gene encodes two transcripts (variants 1 and 2, which differ in their 3'UTR sequences due to an alternative splicing event that removes the SECIS element from the variant 1 transcript. Both transcripts are widely expressed in human cell lines, with the SECIS-containing variant 2 mRNA being more abundant. In vitro experiments demonstrate that the variant 1 3'UTR does not allow readthrough of the UGA/Sec codon. Thus, this transcript would produce a truncated protein that does not contain Sec and cannot make the selenosulfide bond. While the variant 2 3'UTR does support Sec insertion, its activity is weak. Bioinformatic analysis revealed two highly conserved stem-loop structures, one in the proximal part of the variant 2 3'UTR and the other immediately downstream of the SECIS element. The proximal stem-loop promotes Sec insertion in the native context but not when positioned far from the UGA/Sec codon in a heterologous mRNA. In contrast, the 140 nucleotides downstream of the SECIS element inhibit Sec insertion. We also show that endogenous SelS is enriched at perinuclear speckles, in addition to its known localization in the endoplasmic reticulum. Our results suggest the expression of endogenous SelS is more complex than previously appreciated, which has implications for past and future studies on the function of this protein.

  5. tRNAfeature: An algorithm for tRNA features to identify tRNA genes in DNA sequences.

    Yang, Cheng-Hong; Lin, Yu-Da; Chuang, Li-Yeh

    2016-09-01

    The identification of transfer RNAs (tRNAs) is critical for a detailed understanding of the evolution of biological organisms and viruses. However, some tRNAs are difficult to recognize due to their unusual sub-structures and may result in the detection of the wrong anticodon. Therefore, the detection of unusual sub-structures of tRNA genes remains an important challenge. In this study, we propose a method to identify tRNA genes based on tRNA features. tRNAfeature attempts to refold the sequence with single-stranded regions longer than those found in the canonical and conventional structural models for tRNA. We predicted a set of 53926 archaeal, eubacterial and eukaryotic tRNA genes annotated in tRNADB-CE and scanned the tRNA genes in whole genome sequencing. The results indicate that tRNAfeature is more powerful than other existing methods for identifying tRNAs. PMID:27291467

  6. Amino acid modifications on tRNA

    Jing Yuan; Kelly Sheppard; Dieter S(o)ll

    2008-01-01

    The accurate formation of cognate aminoacyl-transfer RNAs (aa-tRNAs) is essential for the fidelity of translation.Most amino acids are esterified onto their cognate tRNA isoacceptors directly by aa.tRNA synthetases.However,in the case of four amino acids (Gin,Asn,Cys and Sec),aminoacyl-tRNAs are made through indirect pathways in many organisms across all three domains of life.The process begins with the charging ofnoncognate amino acids to tRNAs by a specialized synthetase in the case of Cys-tRNAcys formation or by synthetases with relaxed specificity,such as the non-discriminating glutamyl-tRNA,non-discriminating aspartyl-tRNA and seryl-tRNA synthetases.The resulting misacylated tRNAs are then converted to cognate pairs through transformation of the amino acids on the tRNA,which is catalyzed by a group of tRNA-dependent modifying enzymes,such as tRNA-dependent amidotransferases,Sep-tRNA:Cys-tRNA synthase,O-phosphoseryi-tRNA kinase and Sep-tRNA:Sec-tRNA synthase.The majority of these indirect pathways are widely spread in all domains of life and thought to be part of the evolutionary process.

  7. Decameric SelA•tRNA(Sec) ring structure reveals mechanism of bacterial selenocysteine formation.

    Itoh, Yuzuru; Bröcker, Markus J; Sekine, Shun-ichi; Hammond, Gifty; Suetsugu, Shiro; Söll, Dieter; Yokoyama, Shigeyuki

    2013-04-01

    The 21st amino acid, selenocysteine (Sec), is synthesized on its cognate transfer RNA (tRNA(Sec)). In bacteria, SelA synthesizes Sec from Ser-tRNA(Sec), whereas in archaea and eukaryotes SepSecS forms Sec from phosphoserine (Sep) acylated to tRNA(Sec). We determined the crystal structures of Aquifex aeolicus SelA complexes, which revealed a ring-shaped homodecamer that binds 10 tRNA(Sec) molecules, each interacting with four SelA subunits. The SelA N-terminal domain binds the tRNA(Sec)-specific D-arm structure, thereby discriminating Ser-tRNA(Sec) from Ser-tRNA(Ser). A large cleft is created between two subunits and accommodates the 3'-terminal region of Ser-tRNA(Sec). The SelA structures together with in vivo and in vitro enzyme assays show decamerization to be essential for SelA function. SelA catalyzes pyridoxal 5'-phosphate-dependent Sec formation involving Arg residues nonhomologous to those in SepSecS. Different protein architecture and substrate coordination of the bacterial enzyme provide structural evidence for independent evolution of the two Sec synthesis systems present in nature. PMID:23559248

  8. Regulation of Selenocysteine Incorporation into the Selenium Transport Protein, Selenoprotein P*

    Shetty, Sumangala P.; Shah, Ravi; Copeland, Paul R.

    2014-01-01

    Selenoproteins are unique as they contain selenium in their active site in the form of the 21st amino acid selenocysteine (Sec), which is encoded by an in-frame UGA stop codon. Sec incorporation requires both cis- and trans-acting factors, which are known to be sufficient for Sec incorporation in vitro, albeit with low efficiency. However, the abundance of the naturally occurring selenoprotein that contains 10 Sec residues (SEPP1) suggests that processive and efficient Sec incorporation occurs in vivo. Here, we set out to study native SEPP1 synthesis in vitro to identify factors that regulate processivity and efficiency. Deletion analysis of the long and conserved 3′-UTR has revealed that the incorporation of multiple Sec residues is inherently processive requiring only the SECIS elements but surprisingly responsive to the selenium concentration. We provide evidence that processive Sec incorporation is linked to selenium utilization and that reconstitution of known Sec incorporation factors in a wheat germ lysate does not permit multiple Sec incorporation events, thus suggesting a role for yet unidentified mammalian-specific processes or factors. The relationship between our findings and the channeling theory of translational efficiency is discussed. PMID:25063811

  9. Mitochondrial tRNA gene translocations in highly eusocial bees

    Daniela Silvestre

    2006-01-01

    Full Text Available Mitochondrial gene rearrangement events, especially involving tRNA genes, have been described more frequently as more complete mitochondrial genome sequences are becoming available. In the present work, we analyzed mitochondrial tRNA gene rearrangements between two bee species belonging to the tribes Apini and Meliponini within the "corbiculate Apidae". Eleven tRNA genes are in different genome positions or strands. The molecular events responsible for each translocation are explained. Considering the high number of rearrangements observed, the data presented here contradict the general rule of high gene order conservation among closely related organisms, and also represent a powerful molecular tool to help solve questions about phylogeny and evolution in bees.

  10. Interaction of tRNA with MEK2 in pancreatic cancer cells

    Xiaoyun Wang; Christina R. Chow; Kazumi Ebine; Jiyoung Lee; Marsha R Rosner; Tao Pan; Munshi, Hidayatullah G.

    2016-01-01

    Although the translational function of tRNA has long been established, extra translational functions of tRNA are still being discovered. We previously developed a computational method to systematically predict new tRNA-protein complexes and experimentally validated six candidate proteins, including the mitogen-activated protein kinase kinase 2 (MEK2), that interact with tRNA in HEK293T cells. However, consequences of the interaction between tRNA and these proteins remain to be elucidated. Her...

  11. Biosynthesis and functions of sulfur modifications in tRNA

    Shigi, Naoki

    2014-01-01

    Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2-thiouridine (s2U), 4-thiouridine (s4U), 2-thiocytidine (s2C), and 2-methylthioadenosine (ms2A). Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the b...

  12. Real Time Investments with Adequate Portfolio Theory

    Alina Kvietkauskienė

    2015-02-01

    Full Text Available The objective of this paper is to identify investment decision makingschemes using the adequate portfolio model. This approach can be employed to project investment in stocks, using the opportunities offered by the markets and investor intelligence. It was decided to use adequate portfolio theory for investment decision making, simulation of financial markets, and optimisation of utility function. The main conclusion of article suggests investigating return on individual portfolio level. Real investment is a way to make sure of the soundness of applicable strategies.

  13. Translocation and rotation of tRNA during template-independent RNA polymerization by tRNA nucleotidyltransferase.

    Yamashita, Seisuke; Takeshita, Daijiro; Tomita, Kozo

    2014-02-01

    The 3'-terminal CCA (CCA-3' at positions 74-76) of tRNA is synthesized by CCA-adding enzyme using CTP and ATP as substrates, without a nucleic acid template. In Aquifex aeolicus, CC-adding and A-adding enzymes collaboratively synthesize the CCA-3'. The mechanism of CCA-3' synthesis by these two enzymes remained obscure. We now present crystal structures representing CC addition onto tRNA by A. aeolicus CC-adding enzyme. After C₇₄ addition in an enclosed active pocket and pyrophosphate release, the tRNA translocates and rotates relative to the enzyme, and C₇₅ addition occurs in the same active pocket as C₇₄ addition. At both the C₇₄-adding and C₇₅-adding stages, CTP is selected by Watson-Crick-like hydrogen bonds between the cytosine of CTP and conserved Asp and Arg residues in the pocket. After C₇₄C₇₅ addition and pyrophosphate release, the tRNA translocates further and drops off the enzyme, and the CC-adding enzyme terminates RNA polymerization. PMID:24389024

  14. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    Arner, Elias S.J., E-mail: Elias.Arner@ki.se [Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm (Sweden)

    2010-05-01

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Joens Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pK{sub a} of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pK{sub a} difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence

  15. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    Arnér, Elias S J

    2010-05-01

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Jöns Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pK(a) of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pK(a) difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence of

  16. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Joens Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pKa of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pKa difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence of

  17. Volume and geometry of homogeneously adequate knots

    Bartholomew, Paige; McQuarrie, Shane; Purcell, Jessica S.; Weser, Kai

    2014-01-01

    We bound the hyperbolic volumes of a large class of knots and links, called homogeneously adequate knots and links, in terms of their diagrams. To do so, we use the decomposition of these links into ideal polyhedra, developed by Futer, Kalfagianni, and Purcell. We identify essential product disks in these polyhedra.

  18. Adequate supervision for children and adolescents.

    Anderst, James; Moffatt, Mary

    2014-11-01

    Primary care providers (PCPs) have the opportunity to improve child health and well-being by addressing supervision issues before an injury or exposure has occurred and/or after an injury or exposure has occurred. Appropriate anticipatory guidance on supervision at well-child visits can improve supervision of children, and may prevent future harm. Adequate supervision varies based on the child's development and maturity, and the risks in the child's environment. Consideration should be given to issues as wide ranging as swimming pools, falls, dating violence, and social media. By considering the likelihood of harm and the severity of the potential harm, caregivers may provide adequate supervision by minimizing risks to the child while still allowing the child to take "small" risks as needed for healthy development. Caregivers should initially focus on direct (visual, auditory, and proximity) supervision of the young child. Gradually, supervision needs to be adjusted as the child develops, emphasizing a safe environment and safe social interactions, with graduated independence. PCPs may foster adequate supervision by providing concrete guidance to caregivers. In addition to preventing injury, supervision includes fostering a safe, stable, and nurturing relationship with every child. PCPs should be familiar with age/developmentally based supervision risks, adequate supervision based on those risks, characteristics of neglectful supervision based on age/development, and ways to encourage appropriate supervision throughout childhood. PMID:25369578

  19. Nucleotide sequence of Streptomyces griseus initiator tRNA.

    Kuchino, Y; Yamamoto, I.; Nishimura, S.

    1982-01-01

    The primary structure of initiator tRNA from Streptomyces griseus was determined by post-labeling procedures. The nucleotide sequence is pC-G-C-G-G-G-G-U-G-G-A-G-C-A-G-C-U-C-G-G-D-A-G-C-U-C-G-C-U-G-G-G-C-U-C-A-U-A-A-C-C- C-A-G-A-G-G-U-C-G-C-A-G-G-U-psi-C-A-m1A-A-U-C-C-U-G-U-C-C-C-C-G-C-U-A-C-C-A0H. The unique feature of the sequence of this tRNA is that residue 54 is occupied by unmodified U, while ribothymidine is located in that position in most initiator tRNAs from eubacteria.

  20. Acinetobacter species identification by using tRNA spacer fingerprinting.

    Ehrenstein, B; Bernards, A T; Dijkshoorn, L.; Gerner-Smidt, P; Towner, K. J.; Bouvet, P J; Daschner, F D; Grundmann, H

    1996-01-01

    Identification of Acinetobacter spp. to the DNA group level by phenotypic techniques is problematic, and there is a need for an alternative identification method for routine use. The present study validated the suitability of a rapid identification technique based on tRNA spacer (tDNA) fingerprinting in comparison with that of a commercially available assay involving carbon source utilization tests (Biolog MicroStation System) for identifying the 21 DNA-DNA hybridization groups belonging to t...

  1. Photoaffinity labelling of t-RNA binding sites

    For the photoaffinity labelling of E.coli ribosomes in the region of peptidyl transferase, an analogue to the substrate peptidyl-tRNA-ethyl-2-diazomalalonyl-Phe-tRNAsup(Phe) was synthesized. UV irradiation of the reversible complex with 70S ribosomes and poly(U) led to the formation of a covalent bond between N-acyl-Phe-tRNA and 23S-rRNA. The irreversibly bound N-acyl-phenylalanyl group may be transferred to puromycin in a reaction catalyzed by peptidyl transferase, in the presence of the Phe-tRNA, it forms products of a peptide synthesis covalently bound to 23S-RNA. The 23S-rRNA sequence thus labelled, which has not yet been identified, should therefore be in the active centre of the peptidyl transferase or in its near neighbourhood. An analysis of the reaction product showed that the N-acyl-Phe-tRNA is bound specifically to one or more sites of a 3'-terminal 18S fragment of the 23S-RNA. An attempt to prove the existence of further tRNA interaction with ribosonal substrate binding sites led to the discovery of a poly(U2,G)-stimulated, UV-inducible irreversible binding of valin-specific tRNA (E.coli) to 16S-rRNA in one or several tRNA decoding sites. A preliminary analysis of the T1 fragments of tRNAsup(Val) after binding to 16S-rRNA indicates that the DHU loop of tRNA takes part in this photoreaction. (orig.)

  2. tRNA modifications regulate translation during cellular stress

    Gu, Chen; Thomas J Begley; Peter C. Dedon

    2014-01-01

    The regulation of gene expression in response to stress is an essential cellular protection mechanism. Recent advances in tRNA modification analysis and genome-based codon bias analytics have facilitated studies that lead to a novel model for translational control, with translation elongation dynamically regulated during stress responses. Stress-induced increases in specific anticodon wobble bases are required for the optimal translation of stress response transcripts that are significantly b...

  3. Biosynthesis and functions of sulfur modifications in tRNA

    Naoki eShigi

    2014-04-01

    Full Text Available Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2‑thiouridine (s2U, 4-thiouridine (s4U, 2-thiocytidine (s2C, and 2-methylthioadenosine (ms2A. Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific modification enzymes activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes.

  4. Biosynthesis and functions of sulfur modifications in tRNA.

    Shigi, Naoki

    2014-01-01

    Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2-thiouridine (s(2)U), 4-thiouridine (s(4)U), 2-thiocytidine (s(2)C), and 2-methylthioadenosine (ms(2)A). Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur) from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific "modification enzymes" activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes. PMID:24765101

  5. Thiolation Controls Cytoplasmic tRNA Stability and Acts as a Negative Determinant for tRNA Editing in Mitochondria

    Wohlgamuth-Benedum, J. M.; RUBIO, M. A. T.; Paris, Zdeněk; Long, Shaojun; Poliak, Pavel; Lukeš, Julius; Alfonzo, J. D.

    2009-01-01

    Roč. 284, č. 36 (2009), s. 23947-23953. ISSN 0021-9258 R&D Projects: GA ČR GA204/06/1558; GA MŠk LC07032; GA MŠk 2B06129 Institutional research plan: CEZ:AV0Z60220518 Keywords : T. brucei * tRNA * 2-thiolation * Fe-S cluster * editing Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.328, year: 2009

  6. Iron absorption from adequate Filipinos meals

    Iron absorption from adequate Filipino meals representing the three major island groups of the Philippines (Luzon, Visayas, and Mindanao) was studied using double isotope extrinsic tag method. Mean iron absorption of the one-day meal for Metro Manila was 6.6 +- 1.26%. Central Visayas, 6.3 +- 1.15% and Southern Mindanao, 6.4 +- 1.19%. Comparison between meals (breakfast, lunch, dinner) for each region as well as one-day meal for the three regions showed no significant differences (P>0.01). Correlation tests done between iron absorption and the following iron enhancers: ascorbic acid, amount of fish, meat or poultry; and inhibitors: phytic acid and tannic acid, did not give significant results. The overall average of 6.4 +- 1.20% may be used as the iron absorption level from an adequate Filipino meal. This value can be considered as one of the bases for arriving at recommended dietary allowances for iron among Filipinos instead of the 10% iron absorption assumed in 1976. (Auth.). 21 refs.; 3 tabs.; 3 annexes

  7. Iron absorption from adequate Filipino meals

    Iron absorption from adequate Filipino meals representing the three major island groups of the Philippines (Luzon, Visayas and Mindanao) was studied using double isotope extrinsic tag method. Mean iron absorption of the one-day meal for Metro Manila was 6.6 ± 1.26%, Central Visayas, 6.3 ± 1.15% and Southern Mindanao, 6.4 ± 1.19%. Comparison between meals (breakfast, lunch, dinner) for each region as well as one-day meal for the three regions showed no significant differences (P > .01). Correlation tests done between iron absorption and the following iron enhancers: ascorbic acid, amount of fish, meat or poultry and inhibitors: phytic acid and tannic acid did not give significant results. The overall bar x of 6.4 ± 1.20% may be used as the non-heme iron absorption level from an adequate Filipino meal. This value can be considered as one of the bases for arriving at recommended dietary allowances for iron among Filipinos instead of the 10% iron absorption assumed in 1976

  8. Interaction of tRNA with MEK2 in pancreatic cancer cells

    Wang, Xiaoyun; Chow, Christina R.; Ebine, Kazumi; Lee, Jiyoung; Rosner, Marsha R.; Pan, Tao; Munshi, Hidayatullah G.

    2016-01-01

    Although the translational function of tRNA has long been established, extra translational functions of tRNA are still being discovered. We previously developed a computational method to systematically predict new tRNA-protein complexes and experimentally validated six candidate proteins, including the mitogen-activated protein kinase kinase 2 (MEK2), that interact with tRNA in HEK293T cells. However, consequences of the interaction between tRNA and these proteins remain to be elucidated. Here we tested the consequence of the interaction between tRNA and MEK2 in pancreatic cancer cell lines. We also generated disease and drug resistance-derived MEK2 mutants (Q60P, P128Q, S154F, E207K) to evaluate the function of the tRNA-MEK2 interaction. Our results demonstrate that tRNA interacts with the wild-type and mutant MEK2 in pancreatic cancer cells; furthermore, the MEK2 inhibitor U0126 significantly reduces the tRNA-MEK2 interaction. In addition, tRNA affects the catalytic activity of the wild type and mutant MEK2 proteins in different ways. Overall, our findings demonstrate the interaction of tRNA with MEK2 in pancreatic cancer cells and suggest that tRNA may impact MEK2 activity in cancer cells. PMID:27301426

  9. Analysis of the complement and molecular evolution of tRNA genes in cow

    Barris Wesley C

    2009-04-01

    Full Text Available Abstract Background Detailed information regarding the number and organization of transfer RNA (tRNA genes at the genome level is becoming readily available with the increase of DNA sequencing of whole genomes. However the identification of functional tRNA genes is challenging for species that have large numbers of repetitive elements containing tRNA derived sequences, such as Bos taurus. Reliable identification and annotation of entire sets of tRNA genes allows the evolution of tRNA genes to be understood on a genomic scale. Results In this study, we explored the B. taurus genome using bioinformatics and comparative genomics approaches to catalogue and analyze cow tRNA genes. The initial analysis of the cow genome using tRNAscan-SE identified 31,868 putative tRNA genes and 189,183 pseudogenes, where 28,830 of the 31,868 predicted tRNA genes were classified as repetitive elements by the RepeatMasker program. We then used comparative genomics to further discriminate between functional tRNA genes and tRNA-derived sequences for the remaining set of 3,038 putative tRNA genes. For our analysis, we used the human, chimpanzee, mouse, rat, horse, dog, chicken and fugu genomes to predict that the number of active tRNA genes in cow lies in the vicinity of 439. Of this set, 150 tRNA genes were 100% identical in their sequences across all nine vertebrate genomes studied. Using clustering analyses, we identified a new tRNA-GlyCCC subfamily present in all analyzed mammalian genomes. We suggest that this subfamily originated from an ancestral tRNA-GlyGCC gene via a point mutation prior to the radiation of the mammalian lineages. Lastly, in a separate analysis we created phylogenetic profiles for each putative cow tRNA gene using a representative set of genomes to gain an overview of common evolutionary histories of tRNA genes. Conclusion The use of a combination of bioinformatics and comparative genomics approaches has allowed the confident identification of a

  10. Silencing Near tRNA Genes Requires Nucleolar Localization*S

    Wang, Li; Haeusler, Rebecca A.; Good, Paul D.; Thompson, Martin; Nagar, Sapna; Engelke, David R.

    2005-01-01

    Transcription by RNA polymerase II is antagonized by the presence of a nearby tRNA gene in Saccharomyces cerevisiae. To test hypotheses concerning the mechanism of this tRNA gene-mediated (tgm) silencing, the effects of specific gene deletions were determined. The results show that the mechanism of silencing near tRNA genes is fundamentally different from other forms of transcriptional silencing in yeast. Rather, tgm silencing is dependent on the ability to cluster the dispersed tRNA genes in...

  11. Mod5 protein binds to tRNA gene complexes and affects local transcriptional silencing

    Pratt-Hyatt, Matthew; Pai, Dave A.; Haeusler, Rebecca A.; Wozniak, Glenn G.; Good, Paul D.; Miller, Erin L.; McLeod, Ian X.; Yates, John R.; Hopper, Anita K.; Engelke, David R.

    2013-01-01

    This study provides new insight into the requirements for observed silencing of RNA polymerase II transcription near tRNA genes. Mod5 is a conserved tRNA modification enzyme found in both the nucleus and cytoplasm, although it only modifies tRNAs in the cytoplasm. Mod5 is required for silencing near tRNA genes, and it is bound to both nuclear tRNA gene complexes and nuclear pre-tRNA transcripts. Possible mechanisms for this form of RNA-mediated transcriptional silencing are discussed.

  12. Substrate tRNA Recognition Mechanism of a Multisite-specific tRNA Methyltransferase, Aquifex aeolicus Trm1, Based on the X-ray Crystal Structure*

    Awai, Takako; Ochi, Anna; Ihsanawati,; Sengoku, Toru; Hirata, Akira; Bessho, Yoshitaka; Yokoyama, Shigeyuki; Hori, Hiroyuki

    2011-01-01

    Archaeal and eukaryotic tRNA (N2,N2-guanine)-dimethyltransferase (Trm1) produces N2,N2-dimethylguanine at position 26 in tRNA. In contrast, Trm1 from Aquifex aeolicus, a hyper-thermophilic eubacterium, modifies G27 as well as G26. Here, a gel mobility shift assay revealed that the T-arm in tRNA is the binding site of A. aeolicus Trm1. To address the multisite specificity, we performed an x-ray crystal structure study. The overall structure of A. aeolicus Trm1 is similar to that of archaeal Tr...

  13. Loss of a Conserved tRNA Anticodon Modification Perturbs Plant Immunity.

    Ramírez, Vicente; Gonzalez, Beatriz; López, Ana; Castelló, María José; Gil, María José; Etherington, Graham J; Zheng, Bo; Chen, Peng; Vera, Pablo

    2015-10-01

    tRNA is the most highly modified class of RNA species, and modifications are found in tRNAs from all organisms that have been examined. Despite their vastly different chemical structures and their presence in different tRNAs, occurring in different locations in tRNA, the biosynthetic pathways of the majority of tRNA modifications include a methylation step(s). Recent discoveries have revealed unprecedented complexity in the modification patterns of tRNA, their regulation and function, suggesting that each modified nucleoside in tRNA may have its own specific function. However, in plants, our knowledge on the role of individual tRNA modifications and how they are regulated is very limited. In a genetic screen designed to identify factors regulating disease resistance and activation of defenses in Arabidopsis, we identified SUPPRESSOR OF CSB3 9 (SCS9). Our results reveal SCS9 encodes a tRNA methyltransferase that mediates the 2´-O-ribose methylation of selected tRNA species in the anticodon loop. These SCS9-mediated tRNA modifications enhance during the course of infection with the bacterial pathogen Pseudomonas syringae DC3000, and lack of such tRNA modification, as observed in scs9 mutants, severely compromise plant immunity against the same pathogen without affecting the salicylic acid (SA) signaling pathway which regulates plant immune responses. Our results support a model that gives importance to the control of certain tRNA modifications for mounting an effective immune response in Arabidopsis, and therefore expands the repertoire of molecular components essential for an efficient disease resistance response. PMID:26492405

  14. Loss of a Conserved tRNA Anticodon Modification Perturbs Plant Immunity.

    Vicente Ramírez

    2015-10-01

    Full Text Available tRNA is the most highly modified class of RNA species, and modifications are found in tRNAs from all organisms that have been examined. Despite their vastly different chemical structures and their presence in different tRNAs, occurring in different locations in tRNA, the biosynthetic pathways of the majority of tRNA modifications include a methylation step(s. Recent discoveries have revealed unprecedented complexity in the modification patterns of tRNA, their regulation and function, suggesting that each modified nucleoside in tRNA may have its own specific function. However, in plants, our knowledge on the role of individual tRNA modifications and how they are regulated is very limited. In a genetic screen designed to identify factors regulating disease resistance and activation of defenses in Arabidopsis, we identified SUPPRESSOR OF CSB3 9 (SCS9. Our results reveal SCS9 encodes a tRNA methyltransferase that mediates the 2´-O-ribose methylation of selected tRNA species in the anticodon loop. These SCS9-mediated tRNA modifications enhance during the course of infection with the bacterial pathogen Pseudomonas syringae DC3000, and lack of such tRNA modification, as observed in scs9 mutants, severely compromise plant immunity against the same pathogen without affecting the salicylic acid (SA signaling pathway which regulates plant immune responses. Our results support a model that gives importance to the control of certain tRNA modifications for mounting an effective immune response in Arabidopsis, and therefore expands the repertoire of molecular components essential for an efficient disease resistance response.

  15. Is a vegetarian diet adequate for children.

    Hackett, A; Nathan, I; Burgess, L

    1998-01-01

    The number of people who avoid eating meat is growing, especially among young people. Benefits to health from a vegetarian diet have been reported in adults but it is not clear to what extent these benefits are due to diet or to other aspects of lifestyles. In children concern has been expressed concerning the adequacy of vegetarian diets especially with regard to growth. The risks/benefits seem to be related to the degree of restriction of he diet; anaemia is probably both the main and the most serious risk but this also applies to omnivores. Vegan diets are more likely to be associated with malnutrition, especially if the diets are the result of authoritarian dogma. Overall, lacto-ovo-vegetarian children consume diets closer to recommendations than omnivores and their pre-pubertal growth is at least as good. The simplest strategy when becoming vegetarian may involve reliance on vegetarian convenience foods which are not necessarily superior in nutritional composition. The vegetarian sector of the food industry could do more to produce foods closer to recommendations. Vegetarian diets can be, but are not necessarily, adequate for children, providing vigilance is maintained, particularly to ensure variety. Identical comments apply to omnivorous diets. Three threats to the diet of children are too much reliance on convenience foods, lack of variety and lack of exercise. PMID:9670174

  16. tRNA - RMG | LSDB Archive [Life Science Database Archive metadata

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us ...genomes of other plants. Data file File name: rmg_trna.zip File URL: ftp://ftp.biosciencedbc.jp/archive/rmg/...cription Download License Update History of This Database Site Policy | Contact Us tRNA - RMG | LSDB Archive ...

  17. An NMR Approach to tRNA Tertiary Structure in Solution

    Robillard, G.T.; Tarr, C.E.; Vosman, F.; Sussman, J.L.

    1977-01-01

    Atomic coordinates of E. Coli tRNA1Val have been generated from the X-ray crystal structure of Yeast tRNAPhe by base substitution followed by idealization. The NMR spectrum of E. Coli tRNA1Val was then calculated using these coordinates and ring current calculations. The similarity between the calcu

  18. tRNA gene diversity in the three domains of life

    Kosuke eFujishima

    2014-05-01

    Full Text Available Transfer RNA (tRNA is widely known for its key role in decoding mRNA into protein. Despite their necessity and relatively short nucleotide sequences, a large diversity of gene structures and RNA secondary structures of pre-tRNAs and mature tRNAs have recently been discovered in the three domains of life. Growing evidences of disrupted tRNA genes in the genomes of Archaea reveals unique gene structures such as, intron-containing tRNA, split tRNA, and permuted tRNA. Coding sequence for these tRNAs are either separated with introns, fragmented, or permuted at the genome level. Although evolutionary scenario behind the tRNA gene disruption is still unclear, diversity of tRNA structure seems to be co-evolved with their processing enzyme, so-called RNA splicing endonuclease. Metazoan mitochondrial tRNAs (mtRNAs are known for their unique lack of either one or two arms from the typical tRNA cloverleaf structure, while still maintaining functionality. Recently identified nematode-specific V-arm containing tRNAs (nev-tRNAs possess long variable arms that are specific to eukaryotic class II tRNASer and tRNALeu but also decode class I tRNA codons. Moreover, many tRNA-like sequences have been found in the genomes of different organisms and viruses. Thus this review is aimed to cover the latest knowledge on tRNA gene diversity and further recapitulate the evolutionary and biological aspects that caused such uniqueness.

  19. Determination of selenomethionine, selenocysteine, and inorganic selenium in eggs by HPLC-inductively coupled plasma mass spectrometry

    Lipiec, Elzbieta; Siara, Grzegorz [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Pau (France); Warsaw University of Technology, Warsaw (Poland); Bierla, Katarzyna; Ouerdane, Laurent; Szpunar, Joanna [CNRS/UPPA, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Pau (France)

    2010-05-15

    A method for the simultaneous determination of selenomethionine (SeMet), selenocysteine (SeCys), and selenite [Se(IV)] in chicken eggs was developed. A sample preparation protocol including defatting, protein denaturation, and carbamidomethylation was optimized in order to achieve complete protein digestion and to avoid SeCys losses. Quantification was carried out by reversed-phase HPLC-inductively coupled plasma mass spectrometry (ICP MS) after quantitative isolation of the selenium-containing fraction by size-exclusion liquid chromatography. The detection limits were 0.06, 0.003, and 0.01 {mu}g g{sup -1} (dry weight) for SeCys, Se(IV) and SeMet, respectively, and the precision was 5-10%. The end products of carbamidomethylation of the different selenium species were identified for the first time by electrospray QTOF MS after custom-designed 2D HPLC purification. Differences in selenium speciation in egg yolk and white were highlighted, the yolk containing more SeCys and the white more SeMet. An insight into selenium bioaccessibility in eggs was obtained by digestion with simulated gastric and gastrointestinal juices and size-exclusion HPLC-ICP MS. (orig.)

  20. Mutations in the selenocysteine insertion sequence–binding protein 2 gene lead to a multisystem selenoprotein deficiency disorder in humans

    Schoenmakers, Erik; Agostini, Maura; Mitchell, Catherine; Schoenmakers, Nadia; Papp, Laura; Rajanayagam, Odelia; Padidela, Raja; Ceron-Gutierrez, Lourdes; Doffinger, Rainer; Prevosto, Claudia; Luan, Jian’an; Montano, Sergio; Lu, Jun; Castanet, Mireille; Clemons, Nick; Groeneveld, Matthijs; Castets, Perrine; Karbaschi, Mahsa; Aitken, Sri; Dixon, Adrian; Williams, Jane; Campi, Irene; Blount, Margaret; Burton, Hannah; Muntoni, Francesco; O’Donovan, Dominic; Dean, Andrew; Warren, Anne; Brierley, Charlotte; Baguley, David; Guicheney, Pascale; Fitzgerald, Rebecca; Coles, Alasdair; Gaston, Hill; Todd, Pamela; Holmgren, Arne; Khanna, Kum Kum; Cooke, Marcus; Semple, Robert; Halsall, David; Wareham, Nicholas; Schwabe, John; Grasso, Lucia; Beck-Peccoz, Paolo; Ogunko, Arthur; Dattani, Mehul; Gurnell, Mark; Chatterjee, Krishna

    2010-01-01

    Selenium, a trace element that is fundamental to human health, is incorporated into some proteins as selenocysteine (Sec), generating a family of selenoproteins. Sec incorporation is mediated by a multiprotein complex that includes Sec insertion sequence–binding protein 2 (SECISBP2; also known as SBP2). Here, we describe subjects with compound heterozygous defects in the SECISBP2 gene. These individuals have reduced synthesis of most of the 25 known human selenoproteins, resulting in a complex phenotype. Azoospermia, with failure of the latter stages of spermatogenesis, was associated with a lack of testis-enriched selenoproteins. An axial muscular dystrophy was also present, with features similar to myopathies caused by mutations in selenoprotein N (SEPN1). Cutaneous deficiencies of antioxidant selenoenzymes, increased cellular ROS, and susceptibility to ultraviolet radiation–induced oxidative damage may mediate the observed photosensitivity. Reduced levels of selenoproteins in peripheral blood cells were associated with impaired T lymphocyte proliferation, abnormal mononuclear cell cytokine secretion, and telomere shortening. Paradoxically, raised ROS in affected subjects was associated with enhanced systemic and cellular insulin sensitivity, similar to findings in mice lacking the antioxidant selenoenzyme glutathione peroxidase 1 (GPx1). Thus, mutation of SECISBP2 is associated with a multisystem disorder with defective biosynthesis of many selenoproteins, highlighting their role in diverse biological processes. PMID:21084748

  1. Analogies between the tRNA methylating enzymes and tRNA's in embryonic and tumor tissues

    Borek, E.

    1975-01-01

    Progress is reported in the following areas of research, role of tRNA in protein synthesis and as a carrier of amino acids; histidine pathway in Salmonella typhimurium; role of tRNA in regulation of translation; ribosomal binding reactions; role of tRNA in hemoglobin synthesis; population of tRNA's in mutant of Drosophila; methylation of tRNA and DNA by dimethylnitrosamine; purification of DNA methylase from HeLa cell nuclei; effects of age on levels of excretion of tRNA breakdown products in cancer patients; and tyrosyl tRNA's in embryonic and adult liver and in hepatomas. (HLW)

  2. Examining the Gm18 and m1G Modification Positions in tRNA Sequences

    Subramanian, Mayavan; Srinivasan, Thangavelu

    2014-01-01

    The tRNA structure contains conserved modifications that are responsible for its stability and are involved in the initiation and accuracy of the translation process. tRNA modification enzymes are prevalent in bacteria, archaea, and eukaryotes. tRNA Gm18 methyltransferase (TrmH) and tRNA m1G37 methyltransferase (TrmD) are prevalent and essential enzymes in bacterial populations. TrmH involves itself in methylation process at the 2'-OH group of ribose at the 18th position of guanosine (G) in tRNAs. TrmD methylates the G residue next to the anticodon in selected tRNA subsets. Initially, m1G37 modification was reported to take place on three conserved tRNA subsets (tRNAArg, tRNALeu, tRNAPro); later on, few archaea and eukaryotes organisms revealed that other tRNAs also have the m1G37 modification. The present study reveals Gm18, m1G37 modification, and positions of m1G that take place next to the anticodon in tRNA sequences. We selected extremophile organisms and attempted to retrieve the m1G and Gm18 modification bases in tRNA sequences. Results showed that the Gm18 modification G residue occurs in all tRNA subsets except three tRNAs (tRNAMet, tRNAPro, tRNAVal). Whereas the m1G37 modification base G is formed only on tRNAArg, tRNALeu, tRNAPro, and tRNAHis, the rest of the tRNAs contain adenine (A) next to the anticodon. Thus, we hypothesize that Gm18 modification and m1G modification occur irrespective of a G residue in tRNAs. PMID:25031570

  3. Interaction of tRNA with Eukaryotic Ribosome

    Dmitri Graifer

    2015-03-01

    Full Text Available This paper is a review of currently available data concerning interactions of tRNAs with the eukaryotic ribosome at various stages of translation. These data include the results obtained by means of cryo-electron microscopy and X-ray crystallography applied to various model ribosomal complexes, site-directed cross-linking with the use of tRNA derivatives bearing chemically or photochemically reactive groups in the CCA-terminal fragment and chemical probing of 28S rRNA in the region of the peptidyl transferase center. Similarities and differences in the interactions of tRNAs with prokaryotic and eukaryotic ribosomes are discussed with concomitant consideration of the extent of resemblance between molecular mechanisms of translation in eukaryotes and bacteria.

  4. A fungal anticodon nuclease ribotoxin exploits a secondary cleavage site to evade tRNA repair.

    Meineke, Birthe; Kast, Alene; Schwer, Beate; Meinhardt, Friedhelm; Shuman, Stewart; Klassen, Roland

    2012-09-01

    PaOrf2 and γ-toxin subunits of Pichia acaciae toxin (PaT) and Kluyveromyces lactis zymocin are tRNA anticodon nucleases. These secreted ribotoxins are assimilated by Saccharomyces cerevisiae, wherein they arrest growth by depleting specific tRNAs. Toxicity can be recapitulated by induced intracellular expression of PaOrf2 or γ-toxin in S. cerevisiae. Mutational analysis of γ-toxin has identified amino acids required for ribotoxicity in vivo and RNA transesterification in vitro. Here, we report that PaOrf2 residues Glu9 and His287 (putative counterparts of γ-toxin Glu9 and His209) are essential for toxicity. Our results suggest a similar basis for RNA transesterification by PaOrf2 and γ-toxin, despite their dissimilar primary structures and distinctive tRNA target specificities. PaOrf2 makes two sequential incisions in tRNA, the first of which occurs 3' from the mcm(5)s(2)U wobble nucleoside and depends on mcm(5). A second incision two nucleotides upstream results in the net excision of a di-nucleotide. Expression of phage and plant tRNA repair systems can relieve PaOrf2 toxicity when tRNA cleavage is restricted to the secondary site in elp3 cells that lack the mcm(5) wobble U modification. Whereas the endogenous yeast tRNA ligase Trl1 can heal tRNA halves produced by PaOrf2 cleavage in elp3 cells, its RNA sealing activity is inadequate to complete the repair. Compatible sealing activity can be provided in trans by plant tRNA ligase. The damage-rescuing ability of tRNA repair systems is lost when PaOrf2 can break tRNA at both sites. These results highlight the logic of a two-incision mechanism of tRNA anticodon damage that evades productive repair by tRNA ligases. PMID:22836353

  5. Mutations affecting excision of the intron from a eukaryotic dimeric tRNA precursor.

    Willis, I; Hottinger, H; Pearson, D.; Chisholm, V; Leupold, U; Söll, D

    1984-01-01

    The nucleotide sequences of a Schizosaccharomyces pombe opal suppressor serine tRNA gene (sup9-e) and of 12 in vivo-generated mutant genes, which have lost the ability to suppress UGA mutations, have been determined. Analysis of the expression of these genes in Saccharomyces cerevisiae in vitro and in vivo systems has revealed defects in tRNA gene transcription and precursor tRNA processing. Single base changes in the D-loop, the intron and the extra arm affect the efficiency of splicing of t...

  6. Isolation and nucleotide sequence of a mouse histidine tRNA gene.

    Han, J. H.; Harding, J D

    1982-01-01

    We have sequenced a 1307 base pair mouse genomic DNA fragment which contains a histidine tRNA gene. The sequence of the putative mouse histidine tRNA differs from the published sequence of sheep liver histidine tRNA by a single base change in the D-loop. It does not contain an unpaired 5' terminal G residue, as reported for Drosophila and sheep histidine tRNAs. The gene does not contain introns. The 3' flanking region contains a typical RNA polymerase III termination site of 6 consecutive T r...

  7. A one-step method for in vitro production of tRNA transcripts

    Korenčić, Dragana; Söll, Dieter; Ambrogelly, Alexandre

    2002-01-01

    Sequencing of a large number of microbial genomes has led to the discovery of new enzymes involved in tRNA biosynthesis and tRNA function. Preparation of a great variety of RNA molecules is, therefore, of major interest for biochemical characterization of these proteins. We describe a fast, cost-effective and efficient method for in vitro production of tRNA transcripts. T7 RNA polymerase requires a double-stranded DNA promoter in order to initiate transcription; however, elongation does not r...

  8. Lysine tRNA and cell division: a G1 cell cycle mutant is temperature sensitive for the modification of tRNA5Lys to tRNA4Lys.

    Ortwerth, B J; Lin, V K; Lewis, J.; Wang, R. J.

    1984-01-01

    Ts-694 is a temperature sensitive mutant of hamster cells which is blocked in the G1 phase of the cell cycle at the restrictive temperature of 39 degrees. A comparison of the Lys-tRNA isoacceptors by RPC-5 chromatography showed a decrease in tRNA5Lys and an increase in tRNA4Lys at 39 degrees. This was identical to the changes seen in confluent cultures at the permissive temperature of 33 degrees. These Lys-tRNA changes were not seen in ts-694 cells blocked in G1 by isoleucine deficiency, nor ...

  9. Structures of the Bacterial Ribosome in Classical and Hybrid States of tRNA Binding

    Dunkle, Jack A.; Wang, Leyi; Feldman, Michael B.; Pulk, Arto; Chen, Vincent B.; Kapral, Gary J.; Noeske, Jonas; Richardson, Jane S.; Blanchard, Scott C.; Cate, Jamie H. Doudna (Cornell); (UCB); (Duke)

    2011-09-06

    During protein synthesis, the ribosome controls the movement of tRNA and mRNA by means of large-scale structural rearrangements. We describe structures of the intact bacterial ribosome from Escherichia coli that reveal how the ribosome binds tRNA in two functionally distinct states, determined to a resolution of {approx}3.2 angstroms by means of x-ray crystallography. One state positions tRNA in the peptidyl-tRNA binding site. The second, a fully rotated state, is stabilized by ribosome recycling factor and binds tRNA in a highly bent conformation in a hybrid peptidyl/exit site. The structures help to explain how the ratchet-like motion of the two ribosomal subunits contributes to the mechanisms of translocation, termination, and ribosome recycling.

  10. Base-pairing versatility determines wobble sites in tRNA anticodons of vertebrate mitogenomes.

    Miguel M Fonseca

    Full Text Available BACKGROUND: Vertebrate mitochondrial genomes typically have one transfer RNA (tRNA for each synonymous codon family. This limited anticodon repertoire implies that each tRNA anticodon needs to wobble (establish a non-Watson-Crick base pairing between two nucleotides in RNA molecules to recognize one or more synonymous codons. Different hypotheses have been proposed to explain the factors that determine the nucleotide composition of wobble sites in vertebrate mitochondrial tRNA anticodons. Until now, the two major postulates--the "codon-anticodon adaptation hypothesis" and the "wobble versatility hypothesis"--have not been formally tested in vertebrate mitochondria because both make the same predictions regarding the composition of anticodon wobble sites. The same is true for the more recent "wobble cost hypothesis". PRINCIPAL FINDINGS: In this study we have analyzed the occurrence of synonymous codons and tRNA anticodon wobble sites in 1553 complete vertebrate mitochondrial genomes, focusing on three fish species with mtDNA codon usage bias reversal (L-strand is GT-rich. These mitogenomes constitute an excellent opportunity to study the evolution of the wobble nucleotide composition of tRNA anticodons because due to the reversal the predictions for the anticodon wobble sites differ between the existing hypotheses. We observed that none of the wobble sites of tRNA anticodons in these unusual mitochondrial genomes coevolved to match the new overall codon usage bias, suggesting that nucleotides at the wobble sites of tRNA anticodons in vertebrate mitochondrial genomes are determined by wobble versatility. CONCLUSIONS/SIGNIFICANCE: Our results suggest that, at wobble sites of tRNA anticodons in vertebrate mitogenomes, selection favors the most versatile nucleotide in terms of wobble base-pairing stability and that wobble site composition is not influenced by codon usage. These results are in agreement with the "wobble versatility hypothesis".

  11. Competing pathways control host resistance to virus via tRNA modification and programmed ribosomal frameshifting

    Maynard, Nathaniel D.; Macklin, Derek N.; Kirkegaard, Karla; Covert, Markus W

    2012-01-01

    Viral infection depends on a complex interplay between host and viral factors. Here, we link host susceptibility to viral infection to a network encompassing sulfur metabolism, tRNA modification, competitive binding, and programmed ribosomal frameshifting (PRF). We first demonstrate that the iron-sulfur cluster biosynthesis pathway in Escherichia coli exerts a protective effect during lambda phage infection, while a tRNA thiolation pathway enhances viral infection. We show that tRNALys uridin...

  12. tRNA binding properties of eukaryotic translation initiation factor 2 from Encephalitozoon cuniculi.

    Naveau, Marie; Lazennec-Schurdevin, Christine; Panvert, Michel; Mechulam, Yves; Schmitt, Emmanuelle

    2010-10-12

    A critical consequence of the initiation of translation is the setting of the reading frame for mRNA decoding. In eukaryotic and archaeal cells, heterotrimeric initiation factor e/aIF2, in its GTP form, specifically binds Met-tRNA(i)(Met) throughout the translation initiation process. After start codon recognition, the factor, in its GDP-bound form, loses affinity for Met-tRNA(i)(Met) and eventually dissociates from the initiation complex. The role of each aIF2 subunit in tRNA binding has been extensively studied in archaeal systems. The isolated archaeal γ subunit is able to bind tRNA, but the α subunit is required for strong binding. Until now, difficulties during purification have hampered the study of the role of each of the three subunits of eukaryotic eIF2 in specific binding of the initiator tRNA. Here, we have produced the three subunits of eIF2 from Encephalitozoon cuniculi, isolated or assembled into heterodimers or into the full heterotrimer. Using assays following protection of Met-tRNA(i)(Met) against deacylation, we show that the eukaryotic γ subunit is able to bind by itself the initiator tRNA. However, the two peripheral α and β subunits are required for strong binding and contribute equally to tRNA binding affinity. The core domains of α and β probably act indirectly by stabilizing the tRNA binding site on the γ subunit. These results, together with those previously obtained with archaeal aIF2 and yeast eIF2, show species-specific distributions of the roles of the peripheral subunits of e/aIF2 in tRNA binding. PMID:20822097

  13. tRNA sequence data, annotation data and curation data - tRNADB-CE | LSDB Archive [Life Science Database Archive metadata

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us tRNADB-CE tRNA sequence... data, annotation data and curation data Data detail Data name tRNA sequence data, an... first intron 1st Intron end position End position of first intron Seq tRNA sequence Upstream seq. tRNA gene upstream sequence...-leaf secondary structures of tRNA gene Downstream seq. tRNA gene downstream sequence (10 bps) 1st Intron seq. First intron sequence...nd position of second intron 2st Intron seq. Second intron sequence Decision from

  14. "Something Adequate"? In Memoriam Seamus Heaney, Sister Quinlan, Nirbhaya

    Parker, Jan

    2014-01-01

    Seamus Heaney talked of poetry's responsibility to represent the "bloody miracle", the "terrible beauty" of atrocity; to create "something adequate". This article asks, what is adequate to the burning and eating of a nun and the murderous gang rape and evisceration of a medical student? It considers Njabulo…

  15. 40 CFR 716.25 - Adequate file search.

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  16. 9 CFR 305.3 - Sanitation and adequate facilities.

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  17. tRNA binding, positioning, and modification by the pseudouridine synthase Pus10.

    Kamalampeta, Rajashekhar; Keffer-Wilkes, Laura C; Kothe, Ute

    2013-10-23

    Pus10 is the most recently identified pseudouridine synthase found in archaea and higher eukaryotes. It modifies uridine 55 in the TΨC arm of tRNAs. Here, we report the first quantitative biochemical analysis of tRNA binding and pseudouridine formation by Pyrococcus furiosus Pus10. The affinity of Pus10 for both substrate and product tRNA is high (Kd of 30nM), and product formation occurs with a Km of 400nM and a kcat of 0.9s(-1). Site-directed mutagenesis was used to demonstrate that the thumb loop in the catalytic domain is important for efficient catalysis; we propose that the thumb loop positions the tRNA within the active site. Furthermore, a new catalytic arginine residue was identified (arginine 208), which is likely responsible for triggering flipping of the target uridine into the active site of Pus10. Lastly, our data support the proposal that the THUMP-containing domain, found in the N-terminus of Pus10, contributes to binding of tRNA. Together, our findings are consistent with the hypothesis that tRNA binding by Pus10 occurs through an induced-fit mechanism, which is a prerequisite for efficient pseudouridine formation. PMID:23743107

  18. Locating the binding sites of antioxidants resveratrol, genistein and curcumin with tRNA.

    N'soukpoé-Kossi, C N; Bourassa, P; Mandeville, J S; Bekale, L; Bariyanga, J; Tajmir-Riahi, H A

    2015-09-01

    We located the binding sites of antioxidants resveratrol, genistein and curcumin on tRNA in aqueous solution at physiological conditions using constant tRNA concentration and various polyphenol contents. FTIR, UV-visible, CD spectroscopic methods and molecular modeling were used to determine polyphenol binding sites, the binding constant and the effects of polyphenol complexation on tRNA conformation and particle formation. Structural analysis showed that polyphenols bind tRNA via G-C and A-U base pairs through hydrophilic, hydrophobic and H-bonding contacts with overall binding constants of K(res-tRNA)=8.95(±0.80)×10(3) M(-1), K(gen-tRNA)=3.07(±0.5)×10(3) M(-1) and K(cur-tRNA)=1.55(±0.3)×10(4) M(-1). Molecular modeling showed the participation of several nucleobases in polyphenol-tRNA adduct formation with free binding energy of -4.43 for resveratrol, -4.26 kcal/mol for genistein and -4.84 kcal/mol for curcumin, indicating that the interaction process is spontaneous at room temperature. While tRNA remains in A-family structure, major biopolymer aggregation and particle formation occurred at high polyphenol contents. PMID:26093317

  19. Antibiotic inhibition of the movement of tRNA substrates through a peptidyl transferase cavity

    Porse, B T; Rodriguez-Fonseca, C; Leviev, I;

    1996-01-01

    The present review attempts to deal with movement of tRNA substrates through the peptidyl transferase centre on the large ribosomal subunit and to explain how this movement is interrupted by antibiotics. It builds on the concept of hybrid tRNA states forming on ribosomes and on the observed...... movement of the 5' end of P-site-bound tRNA relative to the ribosome that occurs on peptide bond formation. The 3' ends of the tRNAs enter, and move through, a catalytic cavity where antibiotics are considered to act by at least three primary mechanisms: (i) they interfere with the entry of the aminoacyl...... moiety into the catalytic cavity before peptide bond formation; (ii) they inhibit movement of the nascent peptide along the peptide channel, a process that may generally involve destabilization of the peptidyl tRNA, and (iii) they prevent movement of the newly deacylated tRNA between the P/P and hybrid P...

  20. Calcium regulates the expression of a Dictyostelium discoideum asparaginyl tRNA synthetase gene

    Jyoti K Jaiswal; Vidyanand Nanjundiah

    2003-12-01

    In a screen for calcium-regulated gene expression during growth and development of Dictyostelium discoideum we have identified an asparaginyl tRNA synthetase (ddAsnRS) gene, the second tRNA synthetase gene identified in this organism. The ddAsnRS gene shows many unique features. One, it is repressed by lowering cellular calcium, making it the first known calcium-regulated tRNA synthetase. Two, despite the calcium-dependence, its expression is unaltered during the cell cycle, making this the first D. discoideum gene to show a calcium-dependent but cell cycle phase-independent expression. Finally, the N-terminal domain of the predicted ddAsnRS protein shows higher sequence similarity to Glutaminyl tRNA synthetases than to other Asn tRNA synthetases. These unique features of the AsnRS from this primitive eukaryote not only point to a novel mechanism regulating the components of translation machinery and gene expression by calcium, but also hint at a link between the evolution of GlnRS and AsnRS in eukaryotes.

  1. From Prebiotics to Probiotics: The Evolution and Functions of tRNA Modifications.

    McKenney, Katherine M; Alfonzo, Juan D

    2016-01-01

    All nucleic acids in cells are subject to post-transcriptional chemical modifications. These are catalyzed by a myriad of enzymes with exquisite specificity and that utilize an often-exotic array of chemical substrates. In no molecule are modifications more prevalent than in transfer RNAs. In the present document, we will attempt to take a chemical rollercoaster ride from prebiotic times to the present, with nucleoside modifications as key players and tRNA as the centerpiece that drove the evolution of biological systems to where we are today. These ideas will be put forth while touching on several examples of tRNA modification enzymes and their modus operandi in cells. In passing, we submit that the choice of tRNA is not a whimsical one but rather highlights its critical function as an essential invention for the evolution of protein enzymes. PMID:26985907

  2. Saturation of recognition elements blocks evolution of new tRNA identities

    Saint-Léger, Adélaïde; Bello, Carla; Dans, Pablo D.; Torres, Adrian Gabriel; Novoa, Eva Maria; Camacho, Noelia; Orozco, Modesto; Kondrashov, Fyodor A.; Ribas de Pouplana, Lluís

    2016-01-01

    Understanding the principles that led to the current complexity of the genetic code is a central question in evolution. Expansion of the genetic code required the selection of new transfer RNAs (tRNAs) with specific recognition signals that allowed them to be matured, modified, aminoacylated, and processed by the ribosome without compromising the fidelity or efficiency of protein synthesis. We show that saturation of recognition signals blocks the emergence of new tRNA identities and that the rate of nucleotide substitutions in tRNAs is higher in species with fewer tRNA genes. We propose that the growth of the genetic code stalled because a limit was reached in the number of identity elements that can be effectively used in the tRNA structure. PMID:27386510

  3. A voltage-gated pore for translocation of tRNA

    Koley, Sandip; Adhya, Samit, E-mail: nilugrandson@gmail.com

    2013-09-13

    Highlights: •A tRNA translocating complex was assembled from purified proteins. •The complex translocates tRNA at a membrane potential of ∼60 mV. •Translocation requires Cys and His residues in the Fe–S center of RIC6 subunit. -- Abstract: Very little is known about how nucleic acids are translocated across membranes. The multi-subunit RNA Import Complex (RIC) from mitochondria of the kinetoplastid protozoon Leishmania tropica induces translocation of tRNAs across artificial or natural membranes, but the nature of the translocation pore remains unknown. We show that subunits RIC6 and RIC9 assemble on the membrane in presence of subunit RIC4A to form complex R3. Atomic Force Microscopy of R3 revealed particles with an asymmetric surface groove of ∼20 nm rim diameter and ∼1 nm depth. R3 induced translocation of tRNA into liposomes when the pH of the medium was lowered to ∼6 in the absence of ATP. R3-mediated tRNA translocation could also be induced at neutral pH by a K{sup +} diffusion potential with an optimum of 60–70 mV. Point mutations in the Cys{sub 2}–His{sub 2} Fe-binding motif of RIC6, which is homologous to the respiratory Complex III Fe–S protein, abrogated import induced by low pH but not by K{sup +} diffusion potential. These results indicate that the R3 complex forms a pore that is gated by a proton-generated membrane potential and that the Fe–S binding region of RIC6 has a role in proton translocation. The tRNA import complex of L. tropica thus contains a novel macromolecular channel distinct from the mitochondrial protein import pore that is apparently involved in tRNA import in some species.

  4. RNA editing changes the identity of a mitochondrial tRNA in marsupials.

    Börner, G V; Mörl, M.; Janke, A.; Pääbo, S

    1996-01-01

    In the mitochondrial genome of marsupials, the tRNA gene located at the position where in other mammals an aspartyl-tRNA is encoded carries the glycine anticodon GCC. Post-transcriptionally, an RNA editing mechanism affects the second position of the anticodon such that the aspartate anticodon GUC is created in approximately 50% of the mature tRNA pool. We show that the unedited version of this tRNA'Asp' (GCC) can be specifically aminoacylated with glycine in vitro, while the edited version b...

  5. Quantitative single cell monitoring of protein synthesis at subcellular resolution using fluorescently labeled tRNA

    Barhoom, Sima; Kaur, Jaskiran; Cooperman, Barry S.; Smorodinsky, Nechama I.; Smilansky, Zeev; Ehrlich, Marcelo; Elroy-Stein, Orna

    2011-01-01

    We have developed a novel technique of using fluorescent tRNA for translation monitoring (FtTM). FtTM enables the identification and monitoring of active protein synthesis sites within live cells at submicron resolution through quantitative microscopy of transfected bulk uncharged tRNA, fluorescently labeled in the D-loop (fl-tRNA). The localization of fl-tRNA to active translation sites was confirmed through its co-localization with cellular factors and its dynamic alterations upon inhibitio...

  6. Hyperaccurate and error-prone ribosomes exploit distinct mechanisms during tRNA selection

    Zaher, Hani S.; Green, Rachel

    2010-01-01

    Escherichia coli strains displaying hyper-accurate (restrictive) and ribosomal ambiguity (ram) phenotypes have long been associated with alterations in rpsL and rpsD/rpsE, respectively. Crystallographic evidence shows the ribosomal proteins S12 and S4/S5 (corresponding to these genes) to be located in separate regions of the small ribosomal subunit that are important for domain-closure thought to take place during tRNA selection. Mechanistically, the process of tRNA selection is separated int...

  7. Protozoan ALKBH8 Oxygenases Display both DNA Repair and tRNA Modification Activities

    Zdżalik, Daria; Vågbø, Cathrine B; Kirpekar, Finn;

    2014-01-01

    1-8 and FTO. Mammalian and plant ALKBH8 are tRNA hydroxylases targeting 5-methoxycarbonylmethyl-modified uridine (mcm5U) at the wobble position of tRNAGly(UCC). In contrast, the genomes of some bacteria encode a protein with strong sequence homology to ALKBH8, and robust DNA repair activity was......, interestingly, two protozoan ALKBH8s also catalyzed wobble uridine modification of tRNA, thus displaying a dual in vitro activity. Also, we found the modification status of tRNAGly(UCC) to be unaltered in an ALKBH8 deficient mutant of Agrobacterium tumefaciens, indicating that bacterial ALKBH8s have a function...

  8. Anticodon loop mutations perturb reading frame maintenance by the E site tRNA

    Sanders, Christina L.; Lohr, Kristin J.; Gambill, Holly L.; Curran, Ryan B.; Curran, James F.

    2008-01-01

    The ribosomal E site helps hold the reading frame. Certain tRNA mutations affect translation, and anticodon loop mutations can be especially detrimental. We studied the effects of mutations saturating the anticodon loop of the amber suppressor tRNA, Su7, on the ability to help hold the reading frame when in the E site. We also tested three mutations in the anticodon stem, as well as a mutation in the D stem (the “Hirsh” mutation). We used the Escherichia coli RF2 programmed frameshift site to...

  9. Monitoring Protein Synthesis in Living Cells with Fluorescent Labeled tRNA FRET Pairs

    Barhoom, Sima; Farrel, Ian; Dahary, Dvir; Ehrlich, Marcelo; Cooperman, Barry S.; Elroy-Stein, Orna; Smilansky, Zeev

    2013-01-01

    We introduce Protein Synthesis Monitoring (PSM) – a technique to monitor protein synthesis in live cells. In PSM, we transfect cells with tRNA labeled as FRET donors and acceptors. A FRET signal is generated only when a donor- and an acceptor-labeled tRNA come in close contact (< 7nM), as they do on the ribosome during elongation. The intensity of the FRET signal correlates with the number of ribosomes engaged in protein synthesis, providing a real-time, live-cell assay for measuring rates of...

  10. Movement of the 3'-end of tRNA through the peptidyl transferase centre and its inhibition by antibiotics

    Kirillov, Stanislav; Porse, Bo Torben; Vester, Birthe;

    1997-01-01

    Determining how antibiotics inhibit ribosomal activity requires a detailed understanding of the interactions and relative movement of tRNA, mRNA and the ribosome. Recent models for the formation of hybrid tRNA binding sites during the elongation cycle have provided a basis for re-evaluating earlier...... experimental data and, especially, those relevant to substrate movements through the peptidyl transferase centre. With the exception of deacylated tRNA, which binds at the E-site, ribosomal interactions of the 3'-ends of the tRNA substrates generate only a small part of the total free energy of tRNA......-ribosome binding. Nevertheless, these relatively weak interactions determine the unidirectional movement of tRNAs through the ribosome and, moreover, they appear to be particularly susceptible to perturbation by antibiotics. Here we summarise current ideas relating particularly to the movement of the 3'-ends of tRNA...

  11. Tissue- and Time-Specific Expression of Otherwise Identical tRNA Genes.

    Sagi, Dror; Rak, Roni; Gingold, Hila; Adir, Idan; Maayan, Gadi; Dahan, Orna; Broday, Limor; Pilpel, Yitzhak; Rechavi, Oded

    2016-08-01

    Codon usage bias affects protein translation because tRNAs that recognize synonymous codons differ in their abundance. Although the current dogma states that tRNA expression is exclusively regulated by intrinsic control elements (A- and B-box sequences), we revealed, using a reporter that monitors the levels of individual tRNA genes in Caenorhabditis elegans, that eight tryptophan tRNA genes, 100% identical in sequence, are expressed in different tissues and change their expression dynamically. Furthermore, the expression levels of the sup-7 tRNA gene at day 6 were found to predict the animal's lifespan. We discovered that the expression of tRNAs that reside within introns of protein-coding genes is affected by the host gene's promoter. Pairing between specific Pol II genes and the tRNAs that are contained in their introns is most likely adaptive, since a genome-wide analysis revealed that the presence of specific intronic tRNAs within specific orthologous genes is conserved across Caenorhabditis species. PMID:27560950

  12. Transfer RNA: From pioneering crystallographic studies to contemporary tRNA biology.

    Fernández-Millán, Pablo; Schelcher, Cédric; Chihade, Joseph; Masquida, Benoît; Giegé, Philippe; Sauter, Claude

    2016-07-15

    Transfer RNAs (tRNAs) play a key role in protein synthesis as adaptor molecules between messenger RNA and protein sequences on the ribosome. Their discovery in the early sixties provoked a worldwide infatuation with the study of their architecture and their function in the decoding of genetic information. tRNAs are also emblematic molecules in crystallography: the determination of the first tRNA crystal structures represented a milestone in structural biology and tRNAs were for a long period the sole source of information on RNA folding, architecture, and post-transcriptional modifications. Crystallographic data on tRNAs in complex with aminoacyl-tRNA synthetases (aaRSs) also provided the first insight into protein:RNA interactions. Beyond the translation process and the history of structural investigations on tRNA, this review also illustrates the renewal of tRNA biology with the discovery of a growing number of tRNA partners in the cell, the involvement of tRNAs in a variety of regulatory and metabolic pathways, and emerging applications in biotechnology and synthetic biology. PMID:26968773

  13. Fluorescence anisotropy: analysis of tRNA binding to the T box riboswitch antiterminator RNA.

    Zhou, S; Anupam, R; Hines, J V

    2015-01-01

    Fluorescence anisotropy can be utilized in drug discovery screening assays to identify compounds that disrupt medicinally important RNA-macromolecular complexes. Here we describe the application of this technique to monitor tRNA binding to T box riboswitch antiterminator RNA. PMID:25352143

  14. Limited diagnostic value of enzyme analysis in patients with mitochondrial tRNA mutations

    Wibrand, Flemming; Jeppesen, Tina Dysgaard; Frederiksen, Anja L;

    2010-01-01

    We evaluated the diagnostic value of respiratory chain (RC) enzyme analysis of muscle in adult patients with mitochondrial myopathy (MM). RC enzyme activity was measured in muscle biopsies from 39 patients who carry either the 3243A>G mutation, other tRNA point mutations, or single, large...

  15. Mitochondrial tRNA cleavage by tRNA-targeting ribonuclease causes mitochondrial dysfunction observed in mitochondrial disease

    Ogawa, Tetsuhiro, E-mail: atetsu@mail.ecc.u-tokyo.ac.jp; Shimizu, Ayano; Takahashi, Kazutoshi; Hidaka, Makoto; Masaki, Haruhiko, E-mail: amasaki@mail.ecc.u-tokyo.ac.jp

    2014-08-15

    Highlights: • MTS-tagged ribonuclease was translocated successfully to the mitochondrial matrix. • MTS-tagged ribonuclease cleaved mt tRNA and reduced COX activity. • Easy and reproducible method of inducing mt tRNA dysfunction. - Abstract: Mitochondrial DNA (mtDNA) is a genome possessed by mitochondria. Since reactive oxygen species (ROS) are generated during aerobic respiration in mitochondria, mtDNA is commonly exposed to the risk of DNA damage. Mitochondrial disease is caused by mitochondrial dysfunction, and mutations or deletions on mitochondrial tRNA (mt tRNA) genes are often observed in mtDNA of patients with the disease. Hence, the correlation between mt tRNA activity and mitochondrial dysfunction has been assessed. Then, cybrid cells, which are constructed by the fusion of an enucleated cell harboring altered mtDNA with a ρ{sup 0} cell, have long been used for the analysis due to difficulty in mtDNA manipulation. Here, we propose a new method that involves mt tRNA cleavage by a bacterial tRNA-specific ribonuclease. The ribonuclease tagged with a mitochondrial-targeting sequence (MTS) was successfully translocated to the mitochondrial matrix. Additionally, mt tRNA cleavage, which resulted in the decrease of cytochrome c oxidase (COX) activity, was observed.

  16. Mitochondrial tRNA cleavage by tRNA-targeting ribonuclease causes mitochondrial dysfunction observed in mitochondrial disease

    Highlights: • MTS-tagged ribonuclease was translocated successfully to the mitochondrial matrix. • MTS-tagged ribonuclease cleaved mt tRNA and reduced COX activity. • Easy and reproducible method of inducing mt tRNA dysfunction. - Abstract: Mitochondrial DNA (mtDNA) is a genome possessed by mitochondria. Since reactive oxygen species (ROS) are generated during aerobic respiration in mitochondria, mtDNA is commonly exposed to the risk of DNA damage. Mitochondrial disease is caused by mitochondrial dysfunction, and mutations or deletions on mitochondrial tRNA (mt tRNA) genes are often observed in mtDNA of patients with the disease. Hence, the correlation between mt tRNA activity and mitochondrial dysfunction has been assessed. Then, cybrid cells, which are constructed by the fusion of an enucleated cell harboring altered mtDNA with a ρ0 cell, have long been used for the analysis due to difficulty in mtDNA manipulation. Here, we propose a new method that involves mt tRNA cleavage by a bacterial tRNA-specific ribonuclease. The ribonuclease tagged with a mitochondrial-targeting sequence (MTS) was successfully translocated to the mitochondrial matrix. Additionally, mt tRNA cleavage, which resulted in the decrease of cytochrome c oxidase (COX) activity, was observed

  17. Monitoring Protein Synthesis in Living Cells with Fluorescent Labeled tRNA FRET Pairs

    Barhoom, Sima; Farrel, Ian; Dahary, Dvir; Ehrlich, Marcelo; Cooperman, Barry S.; Elroy-Stein, Orna; Smilansky, Zeev

    2013-01-01

    We introduce Protein Synthesis Monitoring (PSM) – a technique to monitor protein synthesis in live cells. In PSM, we transfect cells with tRNA labeled as FRET donors and acceptors. A FRET signal is generated only when a donor- and an acceptor-labeled tRNA come in close contact (< 7nM), as they do on the ribosome during elongation. The intensity of the FRET signal correlates with the number of ribosomes engaged in protein synthesis, providing a real-time, live-cell assay for measuring rates of protein synthesis. PSM can be used to monitor the rate of either total protein synthesis (overall PSM), using bulk tRNAs, or of the synthesis of a specific protein (specific PSM), using specific pairs of tRNA to mark the protein of interest. PSM has sub-micron spatial and sub-second temporal resolutions. Cells continue to live and grow normally, and the synthesized proteins are unchanged since the labeling is on the tRNA itself and not on the amino acid. We have demonstrated specific PSM for monitoring synthesis of a viral protein during viral infection using Isoleucine tRNA, and for monitoring synthesis of collagen during fibrosis in mouse fibroblasts using tRNA-Gly and tRNA-Pro, as collagen is distinguished by many repeats of Gly-Pro dipeptides. We will discuss these results as well as additional applications of PSM in basic research, drug discovery, cell sorting, neurobiology, cancer, biomanufacturing, viral infections, and various protein-synthesis specific diseases.

  18. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    2010-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  19. Assessing Juvenile Sex Offenders to Determine Adequate Levels of Supervision.

    Gerdes, Karen E.; And Others

    1995-01-01

    This study analyzed the internal consistency of four inventories used by Utah probation officers to determine adequate and efficacious supervision levels and placement for juvenile sex offenders. Three factors accounted for 41.2 percent of variance (custodian's and juvenile's attitude toward intervention, offense characteristics, and historical…

  20. Is the Marketing Concept Adequate for Continuing Education?

    Rittenburg, Terri L.

    1984-01-01

    Because educators have a social responsibility to those they teach, the marketing concept may not be adequate as a philosophy for continuing education. In attempting to broaden the audience for continuing education, educators should consider a societal marketing concept to meet the needs of the educationally disadvantaged. (SK)

  1. Co-evolution of tRNA 3′ trailer sequences with 3′ processing enzymes in bacteria

    Li, Zhongwei; Gong, Xin; JOSHI, VEDANG H.; LI, MUXIN

    2005-01-01

    Maturation of the tRNA 3′ terminus is a complicated process in bacteria. Usually, it is initiated by an endonucleolytic cleavage carried out by RNase E and Z in different bacteria. In Escherichia coli, RNase E cleaves AU-rich sequences downstream of tRNA, producing processing intermediates with a few extra residues at the 3′ end; these are then removed by exoribonuclease trimming to generate the mature 3′ end. Here we show that essentially all E. coli tRNA precursors contain a potential RNase...

  2. Selection of functional tRNA primers and primer binding site sequences from a retroviral combinatorial library: identification of new functional tRNA primers in murine leukemia virus replication

    Lund, Anders Henrik; Duch, M; Pedersen, F S

    2000-01-01

    Retroviral reverse transcription is initiated from a cellular tRNA molecule and all known exogenous isolates of murine leukemia virus utilise a tRNA(Pro)molecule. While several studies suggest flexibility in murine leukemia virus primer utilisation, studies on human immunodeficiency virus and avian...... retro-viruses have revealed evidence of molecular adapt-ation towards the specific tRNA isoacceptor used as replication primer. In this study, murine leukemia virus tRNA utilisation is investigated by in vivo screening of a retroviral vector combinatorial library with randomised primer binding sites....... While most of the selected primer binding sites are complementary to the 3'-end of tRNA((Pro)), we also retrieved PBS sequences matching four other tRNA molecules and demonstrate that Akv murine leukemia virus vectors may efficiently replicate using tRNA(Arg(CCU)), tRNA(Phe(GAA))and a hitherto unknown...

  3. ACHIEVEMENT FOR WIRELESS COMMUNICATION USING ADEQUATE MLTI-THREDING ARCHITECTURES

    Rajeev Ranjan

    2015-08-01

    Full Text Available A major role is played in the layout and evaluation of any empirical wireless structure to manifest is the goal of this paper that counterfeit mode architectures affect counterfeit conduct, regarding structure accomplishment metrics, essentially and therefore, the excellent architecture should be explored in order to accomplish the most accurate and reliable results. It is found that the most analytical factors it is found that that actuate counterfeit mode accomplishment are counterfeit time, structure event organizing and grade of adequate. It is, also, found that counterfeit time in relation to event existence in the real structure along with the usage of modern architectural concepts such as multi-interweave technology complement analytical issues too in the advancement of an adequate counterfeit organization for wireless communications. In order to evaluate the above findings an extensive empirical review has been demeanored analysising several distinct events counterfeit organizations towards presenting the relation between channel designing collections, counterfeit time and structure accomplishment.

  4. Arabidopsis: An Adequate Model for Dicot Root Systems?

    Zobel, Richard W.

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to eight different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of t...

  5. Ensuring Adequate Early Childhood Development for Uganda’s Children

    Kasirye, Ibrahim

    2012-01-01

    Although Uganda has made significant progress in reducing child deaths in the past five years, the country still faces major challenges in ensuring adequate early childhood development. This briefing highlights some of the major challenges affecting children during the first five years of life with focus on: the low immunization coverage rates and vaccine availability; poor child nutritional health status; and the limited enrolment of children in Early Childhood Development Centres.

  6. Mode of Action of RNase BN/RNase Z on tRNA Precursors: RNase BN DOES NOT REMOVE THE CCA SEQUENCE FROM tRNA*

    Dutta, Tanmay; Deutscher, Murray P.

    2010-01-01

    RNase BN, the Escherichia coli homolog of RNase Z, was previously shown to act as both a distributive exoribonuclease and an endoribonuclease on model RNA substrates and to be inhibited by the presence of a 3′-terminal CCA sequence. Here, we examined the mode of action of RNase BN on bacteriophage and bacterial tRNA precursors, particularly in light of a recent report suggesting that RNase BN removes CCA sequences (Takaku, H., and Nashimoto, M. (2008) Genes Cells 13, 1087–1097). We show that ...

  7. Transfer-messenger RNA and SmpB mediate bacteriostasis in Escherichia coli cells against tRNA cleavage.

    Sakai, Fusako; Sugita, Risa; Chang, Jung-Wei; Ogawa, Tetsuhiro; Tsumadori, Natsuko; Takahashi, Kazutoshi; Hidaka, Makoto; Masaki, Haruhiko

    2015-10-01

    RNAs, such as mRNA, rRNA and tRNA, are essential macromolecules for cell survival and maintenance. Any perturbation of these molecules, such as by degradation or mutation, can be toxic to cells and may occasionally induce cell death. Therefore, cells have mechanisms known as quality control systems to eliminate abnormal RNAs. Although tRNA is a stable molecule, the anticodon loop is quite susceptible to tRNA-targeting RNases such as colicin E5 and colicin D. However, the mechanism underlying cellular reaction to tRNA cleavage remains unclear. It had long been believed that tRNA cleavage by colicins E5 and D promptly induces cell death because colony formation of the sensitive cells is severely reduced; this indicates that cells do not resist the tRNA cleavage. Here, we show that Escherichia coli cells enter a bacteriostatic state against the tRNA cleavage of colicins D and E5. The bacteriostasis requires small protein B (SmpB) and transfer-messenger RNA (tmRNA), which are known to mediate trans-translation. Furthermore, another type of colicin, colicin E3 cleaving rRNA, immediately reduces the viability of sensitive cells. Moreover, nascent peptide degradation has an additive effect on bacteriostasis. Considering the recent observation that tRNA cleavage may be used as a means of cell-to-cell communication, tRNA cleavage could be used by bacteria not only to dominate other bacteria living in the same niche, but also to regulate growth of their own or other cells. PMID:26199088

  8. Evidence that the mitochondrial leucyl tRNA synthetase (LARS2) gene represents a novel type 2 diabetes susceptibility gene

    hart, Leen M; Hansen, Torben; Rietveld, Ingrid;

    2005-01-01

    Previously, we have shown that a mutation in the mitochondrial DNA-encoded tRNA(Leu(UUR)) gene is associated with type 2 diabetes. One of the consequences of this mutation is a reduced aminoacylation of tRNA(Leu(UUR)). In this study, we have examined whether variants in the leucyl tRNA synthetase...... first report of association between an aminoacyl tRNA synthetase gene and disease. Our results further highlight the important role of mitochondria in glucose homeostasis....

  9. tRNADB-CE: tRNA gene database well-timed in the era of big sequence data

    Takashi eAbe

    2014-05-01

    Full Text Available The tRNA Gene Data Base Curated by Experts tRNADB-CE (http://trna.ie.niigata-u.ac.jp was constructed by analyzing 1,966 complete and 5,272 draft genomes of prokaryotes, 171 viruses’, 121 chloroplasts’, and 12 eukaryotes’ genomes plus fragment sequences obtained by metagenome studies of environmental samples. 595,115 tRNA genes in total, and thus two times of genes compiled previously, have been registered, for which sequence, clover-leaf structure, and results of sequence-similarity and oligonucleotide-pattern searches can be browsed. To provide collective knowledge with help from experts in tRNA researches, we added a column for enregistering comments to each tRNA. By grouping bacterial tRNAs with an identical sequence, we have found high phylogenetic preservation of tRNA sequences, especially at the phylum level. Since many species-unknown tRNAs from metagenomic sequences have sequences identical to those found in species-known prokaryotes, the identical sequence group can provide phylogenetic markers to investigate the microbial community in an environmental ecosystem. This strategy can be applied to a huge amount of short sequences obtained from next-generation sequencers, as showing that tRNADB-CE is a well-timed database in the era of big sequence data. It is also discussed that BLSOM with oligonucleotide composition is useful for efficient knowledge discovery from big sequence data.

  10. tRNA modifying enzymes, NSUN2 and METTL1, determine sensitivity to 5-fluorouracil in HeLa cells.

    Mayumi Okamoto

    2014-09-01

    Full Text Available Nonessential tRNA modifications by methyltransferases are evolutionarily conserved and have been reported to stabilize mature tRNA molecules and prevent rapid tRNA decay (RTD. The tRNA modifying enzymes, NSUN2 and METTL1, are mammalian orthologs of yeast Trm4 and Trm8, which are required for protecting tRNA against RTD. A simultaneous overexpression of NSUN2 and METTL1 is widely observed among human cancers suggesting that targeting of both proteins provides a novel powerful strategy for cancer chemotherapy. Here, we show that combined knockdown of NSUN2 and METTL1 in HeLa cells drastically potentiate sensitivity of cells to 5-fluorouracil (5-FU whereas heat stress of cells revealed no effects. Since NSUN2 and METTL1 are phosphorylated by Aurora-B and Akt, respectively, and their tRNA modifying activities are suppressed by phosphorylation, overexpression of constitutively dephosphorylated forms of both methyltransferases is able to suppress 5-FU sensitivity. Thus, NSUN2 and METTL1 are implicated in 5-FU sensitivity in HeLa cells. Interfering with methylation of tRNAs might provide a promising rationale to improve 5-FU chemotherapy of cancer.

  11. RNA fragments mimicking tRNA analogs interact with cytochrome c.

    Pawlowska, Roza; Janicka, Magdalena; Jedrzejczyk, Dominika; Chworos, Arkadiusz

    2016-04-01

    In times, when drug seeking assays focus on the natural molecular triggers and their analogs, a deeper insight into molecular mechanisms governing the initial step of intrinsic apoptosis (cytochrome c release) is essential to suppress the immortality of pathologically changed cells. In this study, we examined RNA molecules mimicking mitochondrial tRNAs interacting with cytochrome c and possibly affecting its cellular function. tRNA analogs were designed and synthesized prior to the conformational analysis and gel assays clearly stating the nucleic acid-protein complex formation. The circular dichroism spectroscopic (CD) and microscale thermophoresis examination revealed the structural and conformational differences between four tRNA analogs in their interactions with cytochrome c. Obtained CD spectra and gel studies resulted in the complex ratio estimation and conclusion that not only the complex formation may be preferential towards specific tRNAs present in the cell, but nucleobase modifications are not essential for such interaction. PMID:26892782

  12. let-65 is cytoplasmic methionyl tRNA synthetase in C. elegans

    Maha Z. Alriyami

    2014-12-01

    Full Text Available Cytoplasmic methionyl tRNA synthetase (MetRS is one of more than 20 cytoplasmic aminoacyl tRNA synthetase enzymes (ARS. This family of enzymes catalyzes a process fundamental for protein translation. Using a combination of genetic mapping, oligonucleotide array comparative genomic hybridization, and phenotypic correlation, we show that mutations in the essential gene, let-65, reside within the predicted Caenorhabditis elegans homologue of MetRS, which we have named mars-1. We demonstrate that the lethality associated with alleles of let-65 is fully rescued by a transgenic array that spans the mars-1 genomic region. Furthermore, sequence analysis reveals that six let-65 alleles lead to the alteration of highly conserved amino acids.

  13. The structural basis of tRNA mimicry and conformational plasticity by a viral RNA

    Colussi, Timothy M.; Costantino, David A.; Hammond, John A.; Ruehle, Grant M.; Nix, Jay C.; Kieft, Jeffrey S.

    2014-01-01

    RNA is arguably the most functionally diverse biological macromolecule. In some cases a single discrete RNA sequence performs multiple roles and this can be conferred by a complex three-dimensional structure. This multifunctionality can also be driven or enhanced by the ability of a given RNA to assume different conformational (and therefore functional) states1. Despite its biological importance, a detailed structural understanding of the paradigm of RNA structure-driven multifunctionality is lacking. Examples to address this gap are found in single-stranded positive-sense RNA viruses, a prototype being the tRNA-like structure (TLS) found at the 3′ end of the Turnip Yellow Mosaic Virus (TYMV). This TLS not only acts like a tRNA to drive aminoacylation of the viral genomic RNA (gRNA)2-4, but also interacts with other structures in the gRNA's 3′ untranslated region5, contains the promoter for negative strand synthesis, and influences several infection-critical processes6. This TLS RNA can provide a glimpse into the structural basis of RNA multifunctionality and plasticity, but for decades its high-resolution structure has remained elusive. Here, we present the crystal structure of the complete TYMV TLS to 2.0 Å resolution. Globally, the RNA adopts a shape that mimics tRNA, but it uses a very different set of intramolecular interactions to achieve this shape. These interactions also allow the TLS to readily switch conformations. In addition, the TLS structure is ‘two-faced’: one ‘face’ closely mimics tRNA and drives aminoacylation, the other ‘face’ diverges from tRNA and enables additional functionality. The TLS is thus structured to perform several functions and interact with diverse binding partners, and we demonstrate its ability to specifically bind to ribosomes. PMID:24909993

  14. Mitochondrial tRNA import in Trypanosoma brucei is independent of thiolation and the Rieske protein

    Paris, Zdeněk; RUBIO, M. A. T.; Lukeš, Julius; Alfonzo, J. D.

    2009-01-01

    Roč. 15, č. 7 (2009), s. 1398-1406. ISSN 1355-8382 R&D Projects: GA ČR GA204/06/1558; GA MŠk LC07032; GA MŠk 2B06129 Institutional research plan: CEZ:AV0Z60220518 Keywords : T. brucei * tRNA import * 2-thiolation * RIC * Rieske * Fe-S cluster Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.198, year: 2009

  15. RNA Polymerase III Output Is Functionally Linked to tRNA Dimethyl-G26 Modification.

    Aneeshkumar G Arimbasseri

    2015-12-01

    Full Text Available Control of the differential abundance or activity of tRNAs can be important determinants of gene regulation. RNA polymerase (RNAP III synthesizes all tRNAs in eukaryotes and it derepression is associated with cancer. Maf1 is a conserved general repressor of RNAP III under the control of the target of rapamycin (TOR that acts to integrate transcriptional output and protein synthetic demand toward metabolic economy. Studies in budding yeast have indicated that the global tRNA gene activation that occurs with derepression of RNAP III via maf1-deletion is accompanied by a paradoxical loss of tRNA-mediated nonsense suppressor activity, manifested as an antisuppression phenotype, by an unknown mechanism. We show that maf1-antisuppression also occurs in the fission yeast S. pombe amidst general activation of RNAP III. We used tRNA-HydroSeq to document that little changes occurred in the relative levels of different tRNAs in maf1Δ cells. By contrast, the efficiency of N2,N2-dimethyl G26 (m(22G26 modification on certain tRNAs was decreased in response to maf1-deletion and associated with antisuppression, and was validated by other methods. Over-expression of Trm1, which produces m(22G26, reversed maf1-antisuppression. A model that emerges is that competition by increased tRNA levels in maf1Δ cells leads to m(22G26 hypomodification due to limiting Trm1, reducing the activity of suppressor-tRNASerUCA and accounting for antisuppression. Consistent with this, we show that RNAP III mutations associated with hypomyelinating leukodystrophy decrease tRNA transcription, increase m(22G26 efficiency and reverse antisuppression. Extending this more broadly, we show that a decrease in tRNA synthesis by treatment with rapamycin leads to increased m(22G26 modification and that this response is conserved among highly divergent yeasts and human cells.

  16. [Abdominal cure procedures. Adequate use of Nobecutan Spray].

    López Soto, Rosa María

    2009-12-01

    Open abdominal wounds, complicated by infection and/or risk of eventration tend to become chronic and usually require frequent prolonged cure. Habitual changing of bandages develop into one of the clearest risk factors leading to the deterioration of perilesional cutaneous integrity. This brings with it new complications which draw out the evolution of the process, provoking an important deterioration in quality of life for the person who suffers this and a considerable increase in health costs. What is needed is a product and a procedure which control the risk of irritation, which protect the skin, which favor a patient's comfort and which shorten treatment requirements while lowering health care expenses. This report invites medical personnel to think seriously about the scientific rationale, and treatment practice, as to why and how to apply Nobecutan adequately, this reports concludes stating the benefits in the adequate use of this product. The objective of this report is to guarantee the adequate use of this product in treatment of complicated abdominal wounds. This product responds to the needs which are present in these clinical cases favoring skin care apt isolation and protection, while at the same time, facilitating the placement and stability of dressings and bandages used to cure wounds. In order for this to happen, the correct use of this product is essential; medical personnel must pay attention to precautions and recommendations for proper application. The author's experiences in habitual handling of this product during various years, included in the procedures for standardized cures for these wounds, corroborates its usefulness; the author considers use of this product to be highly effective while being simple to apply; furthermore, one succeeds in providing quality care and optimizes resources employed. PMID:20143738

  17. The radiographic appearances following adequate transfusion in β-thalassaemia

    The main lesions of the skull and hand, observed in a group of hypertransfused β-thalassaemic patients, are compared with a control group of low-transfused patients. Bony abnormalities reflect the relationship between proliferating bone marrow and bone cortex, and hypertransfusion therapy will prevent development of lesions only if established early in life. If this is done, the diploe in the skull may become normal, overgrowth of facial bones is moderate, pneumatisation of the paranasal sinuses is not completely prevented, and the 'hair-brush' pattern may disappear completely. A normal appearance of the hand in adequately treated patients differentiates between prepubertal patients and adults. (orig.)

  18. Radiographic appearances following adequate transfusion in. beta. -thalassaemia

    Scutellari, P.N.; Orzincolo, C.; Bagni, B.; Franceschini, F.

    1989-01-01

    The main lesions of the skull and hand, observed in a group of hypertransfused ..beta..-thalassaemic patients, are compared with a control group of low-transfused patients. Bony abnormalities reflect the relationship between proliferating bone marrow and bone cortex, and hypertransfusion therapy will prevent development of lesions only if established early in life. If this is done, the diploe in the skull may become normal, overgrowth of facial bones is moderate, pneumatisation of the paranasal sinuses is not completely prevented, and the 'hair-brush' pattern may disappear completely. A normal appearance of the hand in adequately treated patients differentiates between prepubertal patients and adults.

  19. Controlling translation elongation efficiency: tRNA regulation of ribosome flux on the mRNA.

    Gorgoni, Barbara; Marshall, Elizabeth; McFarland, Matthew R; Romano, M Carmen; Stansfield, Ian

    2014-02-01

    Gene expression can be regulated by a wide variety of mechanisms. One example concerns the growing body of evidence that the protein-production rate can be regulated at the level of translation elongation by controlling ribosome flux across the mRNA. Variations in the abundance of tRNA molecules cause different rates of translation of their counterpart codons. This, in turn, produces a variable landscape of translational rate across each and every mRNA, with the dynamic formation and deformation of ribosomal queues being regulated by both tRNA availability and the rates of translation initiation and termination. In the present article, a range of examples of tRNA control of gene expression are reviewed, and the use of mathematical modelling to develop a predictive understanding of the consequences of that regulation is discussed and explained. These findings encourage a view that predicting the protein-synthesis rate of each mRNA requires a holistic understanding of how each stage of translation, including elongation, contributes to the overall protein-production rate. PMID:24450645

  20. Global analysis of transcriptionally engaged yeast RNA polymerase III reveals extended tRNA transcripts.

    Turowski, Tomasz W; Leśniewska, Ewa; Delan-Forino, Clementine; Sayou, Camille; Boguta, Magdalena; Tollervey, David

    2016-07-01

    RNA polymerase III (RNAPIII) synthesizes a range of highly abundant small stable RNAs, principally pre-tRNAs. Here we report the genome-wide analysis of nascent transcripts attached to RNAPIII under permissive and restrictive growth conditions. This revealed strikingly uneven polymerase distributions across transcription units, generally with a predominant 5' peak. This peak was higher for more heavily transcribed genes, suggesting that initiation site clearance is rate-limiting during RNAPIII transcription. Down-regulation of RNAPIII transcription under stress conditions was found to be uneven; a subset of tRNA genes showed low response to nutrient shift or loss of the major transcription regulator Maf1, suggesting potential "housekeeping" roles. Many tRNA genes were found to generate long, 3'-extended forms due to read-through of the canonical poly(U) terminators. The degree of read-through was anti-correlated with the density of U-residues in the nascent tRNA, and multiple, functional terminators can be located far downstream. The steady-state levels of 3'-extended pre-tRNA transcripts are low, apparently due to targeting by the nuclear surveillance machinery, especially the RNA binding protein Nab2, cofactors for the nuclear exosome, and the 5'-exonuclease Rat1. PMID:27206856

  1. Mitochondrial genomes of praying mantises (Dictyoptera, Mantodea): rearrangement, duplication, and reassignment of tRNA genes.

    Ye, Fei; Lan, Xu-E; Zhu, Wen-Bo; You, Ping

    2016-01-01

    Insect mitochondrial genomes (mitogenomes) contain a conserved set of 37 genes for an extensive diversity of lineages. Previously reported dictyopteran mitogenomes share this conserved mitochondrial gene arrangement, although surprisingly little is known about the mitogenome of Mantodea. We sequenced eight mantodean mitogenomes including the first representatives of two families: Hymenopodidae and Liturgusidae. Only two of these genomes retain the typical insect gene arrangement. In three Liturgusidae species, the trnM genes have translocated. Four species of mantis (Creobroter gemmata, Mantis religiosa, Statilia sp., and Theopompa sp.-HN) have multiple identical tandem duplication of trnR, and Statilia sp. additionally includes five extra duplicate trnW. These extra trnR and trnW in Statilia sp. are erratically arranged and form another novel gene order. Interestingly, the extra trnW is converted from trnR by the process of point mutation at anticodon, which is the first case of tRNA reassignment for an insect. Furthermore, no significant differences were observed amongst mantodean mitogenomes with variable copies of tRNA according to comparative analysis of codon usage. Combined with phylogenetic analysis, the characteristics of tRNA only possess limited phylogenetic information in this research. Nevertheless, these features of gene rearrangement, duplication, and reassignment provide valuable information toward understanding mitogenome evolution in insects. PMID:27157299

  2. Is prophetic discourse adequate to address global economic justice?

    Piet J. Naudé

    2011-06-01

    Full Text Available This article outlined key features of prophetic discourse and investigated whether this form of moral discourse adequately addresses issues of economic injustice. It is shown that the strength of prophetic discourse is its ability to denounce instances of injustice whilst at the same time announcing a God-willed alternative future. The ‘preferential option for the poor’ in Latin American liberation theologies is treated as a case study of the influence of prophetic discourse in contexts of perceived economic injustice. Also the core weaknesses of prophetic discourse are investigated, specifically its incomplete moral argument, weak moral analyses, silence on transition measures, and its inability to take a positive stance on reforms in the system from which itself benefits. In the final section it is concluded that prophetic discourse plays an indispensable role in addressing issues of global economic justice, but – taken by itself – it is not an adequate form of moral discourse to address concrete matters of justice.

  3. Adequate drainage system design for heap leaching structures.

    Majdi, Abbas; Amini, Mehdi; Nasab, Saeed Karimi

    2007-08-17

    The paper describes an optimum design of a drainage system for a heap leaching structure which has positive impacts on both mine environment and mine economics. In order to properly design a drainage system the causes of an increase in the acid level of the heap which in turn produces severe problems in the hydrometallurgy processes must be evaluated. One of the most significant negative impacts induced by an increase in the acid level within a heap structure is the increase of pore acid pressure which in turn increases the potential of a heap-slide that may endanger the mine environment. In this paper, initially the thickness of gravelly drainage layer is determined via existing empirical equations. Then by assuming that the calculated thickness is constant throughout the heap structure, an approach has been proposed to calculate the required internal diameter of the slotted polyethylene pipes which are used for auxiliary drainage purposes. In order to adequately design this diameter, the pipe's cross-sectional deformation due to stepped heap structure overburden pressure is taken into account. Finally, a design of an adequate drainage system for the heap structure 2 at Sarcheshmeh copper mine is presented and the results are compared with those calculated by exiting equations. PMID:17321044

  4. Nuclear waste disposal: achieving adequate financing - special study

    An analysis by the Congressional Budget Office (CBO) evaluates whether the current one mill fee now charged to nuclear-electricity consumers will adequately finance the waste disposal program. The CBO found that, if the fee is adjusted annually for inflation, it should provide enough revenues to cover all program costs under all nuclear growth forecasts. If the fee is unchanged, however, the fees will be inadequate if inflation exceeds 3% annually. The report suggests two alternatives for fee revision, but makes no recommendations. The alternatives are to increase the fee only at specific intervals or to automatically adjust the fee through indexation. The report examines the effect of delaying the program, cost overruns, and alternative inflation rate and interest rate assumptions. 3 figures, 12 tables

  5. CAN A SINGLE SECURITY FRAMEWORK ADDRESS INFORMATION SECURITY RISKS ADEQUATELY?

    Walid Al-Ahmad

    2012-01-01

    Full Text Available There is no doubt that modern society depends heavily on information technology in nearly every facet of human activity. Organizations of all kinds are increasingly exposed to various kinds of risks, including information technology risks. There are many security standards and frameworks available to help organizations manage these risks. The question which one is best and can address the information security risks adequately warrants further investigation and research. The purpose of this research work is to highlight the challenges facing enterprises in their efforts to properly manage information security risks when adopting international standards and frameworks. To assist in selecting the best framework to use in risk management, the article presents an overview of the most popular and widely used standards. It then identifies some selection criteria and suggests an approach to proper implementation. A case study is used to prove the usefulness of the new model for selecting an appropriate security model to manage information security risks.

  6. A human tRNA methyltransferase 9-like protein prevents tumour growth by regulating LIN9 and HIF1-α.

    Begley, Ulrike; Sosa, Maria Soledad; Avivar-Valderas, Alvaro; Patil, Ashish; Endres, Lauren; Estrada, Yeriel; Chan, Clement T Y; Su, Dan; Dedon, Peter C; Aguirre-Ghiso, Julio A; Begley, Thomas

    2013-03-01

    Emerging evidence points to aberrant regulation of translation as a driver of cell transformation in cancer. Given the direct control of translation by tRNA modifications, tRNA modifying enzymes may function as regulators of cancer progression. Here, we show that a tRNA methyltransferase 9-like (hTRM9L/KIAA1456) mRNA is down-regulated in breast, bladder, colorectal, cervix and testicular carcinomas. In the aggressive SW620 and HCT116 colon carcinoma cell lines, hTRM9L is silenced and its re-expression and methyltransferase activity dramatically suppressed tumour growth in vivo. This growth inhibition was linked to decreased proliferation, senescence-like G0/G1-arrest and up-regulation of the RB interacting protein LIN9. Additionally, SW620 cells re-expressing hTRM9L did not respond to hypoxia via HIF1-α-dependent induction of GLUT1. Importantly, hTRM9L-negative tumours were highly sensitive to aminoglycoside antibiotics and this was associated with altered tRNA modification levels compared to antibiotic resistant hTRM9L-expressing SW620 cells. Our study links hTRM9L and tRNA modifications to inhibition of tumour growth via LIN9 and HIF1-α-dependent mechanisms. It also suggests that aminoglycoside antibiotics may be useful to treat hTRM9L-deficient tumours. PMID:23381944

  7. Allosteric vs. spontaneous exit-site (E-site) tRNA dissociation early in protein synthesis.

    Chen, Chunlai; Stevens, Benjamin; Kaur, Jaskiran; Smilansky, Zeev; Cooperman, Barry S; Goldman, Yale E

    2011-10-11

    During protein synthesis, deacylated transfer RNAs leave the ribosome via an exit (E) site after mRNA translocation. How the ribosome regulates tRNA dissociation and whether functional linkages between the aminoacyl (A) and E sites modulate the dynamics of protein synthesis have long been debated. Using single molecule fluorescence resonance energy transfer experiments, we find that, during early cycles of protein elongation, tRNAs are often held in the E site until being allosterically released when the next aminoacyl tRNA binds to the A site. This process is regulated by the length and sequence of the nascent peptide and by the conformational state, detected by tRNA proximity, prior to translocation. In later cycles, E-site tRNA dissociates spontaneously. Our results suggest that the distribution of pretranslocation tRNA states and posttranslocation pathways are correlated within each elongation cycle via communication between distant subdomains in the ribosome, but that this correlation between elongation cycle intermediates does not persist into succeeding cycles. PMID:21969541

  8. Dose Limits for Man do not Adequately Protect the Ecosystem

    Higley, Kathryn A.; Alexakhin, Rudolf M.; McDonald, Joseph C.

    2004-08-01

    It has been known for quite some time that different organisms display differing degrees of sensitivity to the effects of ionizing radiations. Some microorganisms such as the bacterium Micrococcus radiodurans, along with many species of invertebrates, are extremely radio-resistant. Humans might be categorized as being relatively sensitive to radiation, and are a bit more resistant than some pine trees. Therefore, it could be argued that maintaining the dose limits necessary to protect humans will also result in the protection of most other species of flora and fauna. This concept is usually referred to as the anthropocentric approach. In other words, if man is protected then the environment is also adequately protected. The ecocentric approach might be stated as; the health of humans is effectively protected only when the environment is not unduly exposed to radiation. The ICRP is working on new recommendations dealing with the protection of the environment, and this debate should help to highlight a number of relevant issues concerning that topic.

  9. Adequate peritoneal dialysis: theoretical model and patient treatment.

    Tast, C

    1998-01-01

    The objective of this study was to evaluate the relationship between adequate PD with sufficient weekly Kt/V (2.0) and Creatinine clearance (CCR) (60l) and necessary daily dialysate volume. This recommended parameter was the result of a recent multi-centre study (CANUSA). For this there were 40 patients in our hospital examined and compared in 1996, who carried out PD for at least 8 weeks and up to 6 years. These goals (CANUSA) are easily attainable in the early treatment of many individuals with a low body surface area (BSA). With higher BSA or missing RRF (Residual Renal Function) the daily dose of dialysis must be adjusted. We found it difficult to obtain the recommended parameters and tried to find a solution to this problem. The simplest method is to increase the volume or exchange rate. The most expensive method is to change from CAPD to APD with the possibility of higher volume or exchange rates. Selection of therapy must take into consideration: 1. patient preference, 2. body mass, 3. peritoneal transport rates, 4. ability to perform therapy, 5. cost of therapy and 6. risk of peritonitis. With this information in mind, an individual prescription can be formulated and matched to the appropriate modality of PD. PMID:10392062

  10. Structural Insights into the Polyphyletic Origins of Glycyl tRNA Synthetases*♦

    Valencia-Sánchez, Marco Igor; Rodríguez-Hernández, Annia; Ferreira, Ruben; Santamaría-Suárez, Hugo Aníbal; Arciniega, Marcelino; Dock-Bregeon, Anne-Catherine; Moras, Dino; Beinsteiner, Brice; Brieba, Luis G.; Grøtli, Morten

    2016-01-01

    Glycyl tRNA synthetase (GlyRS) provides a unique case among class II aminoacyl tRNA synthetases, with two clearly widespread types of enzymes: a dimeric (α2) species present in some bacteria, archaea, and eukaryotes; and a heterotetrameric form (α2β2) present in most bacteria. Although the differences between both types of GlyRS at the anticodon binding domain level are evident, the extent and implications of the variations in the catalytic domain have not been described, and it is unclear whether the mechanism of amino acid recognition is also dissimilar. Here, we show that the α-subunit of the α2β2 GlyRS from the bacterium Aquifex aeolicus is able to perform the first step of the aminoacylation reaction, which involves the activation of the amino acid with ATP. The crystal structure of the α-subunit in the complex with an analog of glycyl adenylate at 2.8 Å resolution presents a conformational arrangement that properly positions the cognate amino acid. This work shows that glycine is recognized by a subset of different residues in the two types of GlyRS. A structural and sequence analysis of class II catalytic domains shows that bacterial GlyRS is closely related to alanyl tRNA synthetase, which led us to define a new subclassification of these ancient enzymes and to propose an evolutionary path of α2β2 GlyRS, convergent with α2 GlyRS and divergent from AlaRS, thus providing a possible explanation for the puzzling existence of two proteins sharing the same fold and function but not a common ancestor. PMID:27226617

  11. Structural Insights into the Polyphyletic Origins of Glycyl tRNA Synthetases.

    Valencia-Sánchez, Marco Igor; Rodríguez-Hernández, Annia; Ferreira, Ruben; Santamaría-Suárez, Hugo Aníbal; Arciniega, Marcelino; Dock-Bregeon, Anne-Catherine; Moras, Dino; Beinsteiner, Brice; Mertens, Haydyn; Svergun, Dmitri; Brieba, Luis G; Grøtli, Morten; Torres-Larios, Alfredo

    2016-07-01

    Glycyl tRNA synthetase (GlyRS) provides a unique case among class II aminoacyl tRNA synthetases, with two clearly widespread types of enzymes: a dimeric (α2) species present in some bacteria, archaea, and eukaryotes; and a heterotetrameric form (α2β2) present in most bacteria. Although the differences between both types of GlyRS at the anticodon binding domain level are evident, the extent and implications of the variations in the catalytic domain have not been described, and it is unclear whether the mechanism of amino acid recognition is also dissimilar. Here, we show that the α-subunit of the α2β2 GlyRS from the bacterium Aquifex aeolicus is able to perform the first step of the aminoacylation reaction, which involves the activation of the amino acid with ATP. The crystal structure of the α-subunit in the complex with an analog of glycyl adenylate at 2.8 Å resolution presents a conformational arrangement that properly positions the cognate amino acid. This work shows that glycine is recognized by a subset of different residues in the two types of GlyRS. A structural and sequence analysis of class II catalytic domains shows that bacterial GlyRS is closely related to alanyl tRNA synthetase, which led us to define a new subclassification of these ancient enzymes and to propose an evolutionary path of α2β2 GlyRS, convergent with α2 GlyRS and divergent from AlaRS, thus providing a possible explanation for the puzzling existence of two proteins sharing the same fold and function but not a common ancestor. PMID:27226617

  12. tRNA properties help shape codon pair preferences in open reading frames

    Buchan, J. Ross; Aucott, Lorna S; Stansfield, Ian

    2006-01-01

    Translation elongation is an accurate and rapid process, dependent upon efficient juxtaposition of tRNAs in the ribosomal A- and P-sites. Here, we sought evidence of A- and P-site tRNA interaction by examining bias in codon pair choice within open reading frames from a range of genomes. Three distinct and marked effects were revealed once codon and dipeptide biases had been subtracted. First, in the majority of genomes, codon pair preference is primarily determined by a tetranucleotide combin...

  13. The role of mitochondrial tRNA variants in female breast cancer.

    Meng, Xian-Li; Meng, Hua; Zhang, Wei; Qin, Yu-Hua; Zhao, Ning-Min

    2016-09-01

    Mitochondrial tRNA (Mt-tRNA) variants have been found to be involved in the carcinogenesis of breast cancer. These tRNAs, which played critical roles in mitochondrial protein synthesis, were important regulators in tumorigenesis. Distinguishing the polymorphisms or mutations in mt-tRNA genes was still puzzling for the clinicians and geneticists when confronted with the breast cancer. In this study, we performed a detailed analysis of recently reported mutations in mt-tRNA genes and further discussed the relationship between these variants and breast cancer. PMID:25703847

  14. A fungal anticodon nuclease ribotoxin exploits a secondary cleavage site to evade tRNA repair

    Meineke, Birthe; Kast, Alene; Schwer, Beate; Meinhardt, Friedhelm; Shuman, Stewart; Klassen, Roland

    2012-01-01

    The PaOrf2 and γ-toxin subunits of Pichia acaciae toxin (PaT) and Kluyveromyces lactis zymocin are tRNA anticodon nucleases encoded by cytoplasmic DNA plasmids. Toxicity can be recapitulated conveniently by induced intracellular expression of PaOrf2 or γ-toxin in Saccharomyces cerevisiae. Mutational analysis of γ-toxin has identified amino acids required for ribotoxicity in vivo and RNA transesterification in vitro. Here, the authors report that PaOrf2 residues Glu9 and His287 (putative count...

  15. Selection of tRNA charging quality control mechanisms that increase mistranslation of the genetic code

    Yadavalli, Srujana S; Ibba, Michael

    2013-01-01

    Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms...... are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone...

  16. Selective charging of tRNA isoacceptors induced by amino-acid starvation

    Dittmar, K. A.; Sørensen, Michael Askvad; Elf, J.;

    2005-01-01

    -acid starvation results in 'selective charging' where the charging levels of some tRNA isoacceptors will be low and those of others will remain high. Here, we developed a microarray for the analysis of charged fractions of tRNAs and measured charging for all Escherichia coli tRNAs before and during leucine......, threonine or arginine starvation. Before starvation, most tRNAs were fully charged. During starvation, the isoacceptors in the leucine, threonine or arginine families showed selective charging when cells were starved for their cognate amino acid, directly confirming the theoretical prediction. Codons read...

  17. Aquifex aeolicus tRNA (N2,N2-Guanine)-dimethyltransferase (Trm1) Catalyzes Transfer of Methyl Groups Not Only to Guanine 26 but Also to Guanine 27 in tRNA*

    Awai, Takako; Kimura, Satoshi; Tomikawa, Chie; Ochi, Anna; Ihsanawati,; Bessho, Yoshitaka; Yokoyama, Shigeyuki; Ohno, Satoshi; Nishikawa, Kazuya; Yokogawa, Takashi; Suzuki, Tsutomu; Hori, Hiroyuki

    2009-01-01

    Transfer RNA (N2,N2-guanine)-dimethyltransferase (Trm1) catalyzes N2,N2-dimethylguanine formation at position 26 (m22G26) in tRNA. In the reaction, N2-guanine at position 26 (m2G26) is generated as an intermediate. The trm1 genes are found only in archaea and eukaryotes, although it has been reported that Aquifex aeolicus, a hyper-thermophilic eubacterium, has a putative trm1 gene. To confirm whether A. aeolicus Trm1 has tRNA methyltransferase activity, we purified recombinant Trm1 protein. I...

  18. Anticodon Modifications in the tRNA Set of LUCA and the Fundamental Regularity in the Standard Genetic Code

    van der Gulik, Peter T. S.; Hoff, Wouter D.

    2016-01-01

    Based on (i) an analysis of the regularities in the standard genetic code and (ii) comparative genomics of the anticodon modification machinery in the three branches of life, we derive the tRNA set and its anticodon modifications as it was present in LUCA. Previously we proposed that an early ancestor of LUCA contained a set of 23 tRNAs with unmodified anticodons that was capable of translating all 20 amino acids while reading 55 of the 61 sense codons of the standard genetic code (SGC). Here we use biochemical and genomic evidence to derive that LUCA contained a set of 44 or 45 tRNAs containing 2 or 3 modifications while reading 59 or 60 of the 61 sense codons. Subsequent tRNA modifications occurred independently in the Bacteria and Eucarya, while the Archaea have remained quite close to the tRNA set as it was present in LUCA. PMID:27454314

  19. The ribosome triggers the stringent response by RelA via a highly distorted tRNA.

    Agirrezabala, Xabier; Fernández, Israel S; Kelley, Ann C; Cartón, David Gil; Ramakrishnan, Venki; Valle, Mikel

    2013-09-01

    The bacterial stringent response links nutrient starvation with the transcriptional control of genes. This process is initiated by the stringent factor RelA, which senses the presence of deacylated tRNA in the ribosome as a symptom of amino-acid starvation to synthesize the alarmone (p)ppGpp. Here we report a cryo-EM study of RelA bound to ribosomes bearing cognate, deacylated tRNA in the A-site. The data show that RelA on the ribosome stabilizes an unusual distorted form of the tRNA, with the acceptor arm making contact with RelA and far from its normal location in the peptidyl transferase centre. PMID:23877429

  20. La adaptación a la deficiencia de zinc en cianobacterias. Papel de treonil-trna sintetasas duplicadas

    Rubio Gómez, Miguel Ángel

    2016-01-01

    Falta palabras claves Las aminoacil tRNA sintetasas (aaRSs) son las enzimas que catalizan la carga del aminoácido en el tRNA y son las responsables de mantener la fidelidad en la traducción del código genético. Las aaRSs son componentes esenciales de la síntesis proteica y son ubicuas en todos los dominios de la vida (Ibba y Sol, 2000; Perona y Hadd, 2012). La cianobacteria filamentosa Anabaena sp.PCC 7120 contiene dos genes de treonil tRNA sintetasa, alr0335(thrS1) y all4723 (thrS2), ...

  1. Monitoring the eye lens: which dose quantity is adequate?

    Behrens, R [Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany); Dietze, G, E-mail: rolf.behrens@ptb.d [Paracelsusstrasse 7, D-38116 Braunschweig (Germany)

    2010-07-21

    Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. The question of which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens arises from this situation. While in many countries dosemeters calibrated in terms of the dose equivalent quantity H{sub p}(0.07) have been seen as being adequate for monitoring the dose to the eye lens, this might be questionable in the case of reduced dose limits and, thus, it may become necessary to use the dose equivalent quantity H{sub p}(3) for this purpose. To discuss this question, the dose conversion coefficients for the equivalent dose of the eye lens (in the following eye lens dose) were determined for realistic photon and beta radiation fields and compared with the values of the corresponding conversion coefficients for the different operational quantities. The values obtained lead to the following conclusions: in radiation fields where most of the dose comes from photons, especially x-rays, it is appropriate to use dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom, while in other radiation fields (dominated by beta radiation or unknown contributions of photon and beta radiation) dosemeters calibrated in terms of H{sub p}(3) on a slab phantom should be used. As an alternative, dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom could also be used; however, in radiation fields containing beta radiation with the end point energy near 1 MeV, an overestimation of the eye lens dose by up to a factor of 550 is possible.

  2. Monitoring the eye lens: which dose quantity is adequate?

    Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. The question of which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens arises from this situation. While in many countries dosemeters calibrated in terms of the dose equivalent quantity Hp(0.07) have been seen as being adequate for monitoring the dose to the eye lens, this might be questionable in the case of reduced dose limits and, thus, it may become necessary to use the dose equivalent quantity Hp(3) for this purpose. To discuss this question, the dose conversion coefficients for the equivalent dose of the eye lens (in the following eye lens dose) were determined for realistic photon and beta radiation fields and compared with the values of the corresponding conversion coefficients for the different operational quantities. The values obtained lead to the following conclusions: in radiation fields where most of the dose comes from photons, especially x-rays, it is appropriate to use dosemeters calibrated in terms of Hp(0.07) on a slab phantom, while in other radiation fields (dominated by beta radiation or unknown contributions of photon and beta radiation) dosemeters calibrated in terms of Hp(3) on a slab phantom should be used. As an alternative, dosemeters calibrated in terms of Hp(0.07) on a slab phantom could also be used; however, in radiation fields containing beta radiation with the end point energy near 1 MeV, an overestimation of the eye lens dose by up to a factor of 550 is possible.

  3. Crosslinking of tRNA containing a long extra arm to elongation factor Tu by trans-diamminedichloroplatinum(II)

    Rasmussen, Nils-Jørgen; Wikman, Friedrik; Clark, Brian F. C.

    1990-01-01

    A tRNA containing a long extra arm, namely E. coli tRNA1Leu has been crosslinked to elongation factor Tu, with the crosslinking reagent trans-diamminedichloroplatinum(II). The nucleotide involved in the crosslinking was identified to be a guanosine in the variable region at position 47F or 47G....

  4. PLMItRNA, a database for mitochondrial tRNA genes and tRNAs in photosynthetic eukaryotes

    Damiano, Fabrizio; Gallerani, Raffaele; Liuni, Sabino; Licciulli, Flavio; Ceci, Luigi R.

    2001-01-01

    The PLMItRNA database for mitochondrial tRNA molecules and genes in Viridiplantae (green plants) [Volpetti,V., Gallerani,R., DeBenedetto,C., Liuni,S., Licciulli,F. and Ceci,L.R. (2000) Nucleic Acids Res., 28, 159–162] has been enlarged to include algae. The database now contains 436 genes and 16 tRNA entries relative to 25 higher plants, eight green algae, four red algae (Rhodophytae) and two Stramenopiles. The PLMItRNA database is accessible via the WWW at http://bio-www.ba.cnr.it:8000/PLMItRNA. PMID:11125079

  5. Small tandemly repeated DNA sequences of higher plants likely originate from a tRNA gene ancestor.

    Benslimane, A A; Dron, M; Hartmann, C; Rode, A.

    1986-01-01

    Several monomers (177 bp) of a tandemly arranged repetitive nuclear DNA sequence of Brassica oleracea have been cloned and sequenced. They share up to 95% homology between one another and up to 80% with other satellite DNA sequences of Cruciferae, suggesting a common ancestor. Both strands of these monomers show more than 50% homology with many tRNA genes; the best homologies have been obtained with Lys and His yeast mitochondrial tRNA genes (respectively 64% and 60%). These results suggest t...

  6. Duplication and Remolding of tRNA Genes in the Mitochondrial Genome of Reduvius tenebrosus (Hemiptera: Reduviidae)

    Pei Jiang; Hu Li; Fan Song; Yao Cai; Jianyun Wang; Jinpeng Liu; Wanzhi Cai

    2016-01-01

    Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, includ...

  7. Structure and Activity of an Aminoacyl-tRNA Synthetase that Charges tRNA with Nitro-Tryptophan

    Buddha,M.; Crane, B.

    2005-01-01

    The most divergent of two tryptophanyl tRNA synthetases (TrpRS II) found in Deinococcus radiodurans interacts with a nitric oxide synthase protein that produces 4-nitro-tryptophan (4-NRP). TrpRS II efficiently charges transfer RNATrp with 4-NRP and 5-hydroxy-tryptophan (5-HRP). The crystal structures of TrpRS II bound to tryptophan and 5-HRP reveal residue substitutions that accommodate modified indoles. A class of auxiliary bacterial TrpRSs conserve this capacity to charge tRNA with nonstandard amino acids.

  8. Escherichia coli B lacks one of the two initiator tRNA species present in E. coli K-12.

    Mandal, N; RajBhandary, U L

    1992-01-01

    We show that the metY locus which specifies tRNA(2fMet) in Escherichia coli K-12 specifies tRNA(1fMet) in E. coli B. This conclusion is based on results of Southern blot analysis of E. coli B and K-12 DNAs and on polymerase chain reaction amplification, cloning, and sequencing of an approximately 200-bp region of DNA corresponding to the metY loci of E. coli B and E. coli K-12. We also show that the metY locus of E. coli B is transcriptionally active. E. coli strains transformed with the mult...

  9. The Pai-associated leuX specific tRNA5(Leu) affects type 1fimbriation in pathogenic Escherichia coli by control of FimB recombinase expression

    Ritter, A.; Gally, D.; Olsen, Peter Bjarke;

    1997-01-01

    The uropathogenic Escherichia coli strain 536 (06:K15:H31) carries two large chromosomalpathogenicity islands (Pais). Both Pais are flanked by tRNA genes. Spontaneous deletion of Pai IIresults in truncation of the leuX tRNA5Leu gene. This tRNA is required for the expression of type 1fimbriae (Fim...

  10. Trm9-Catalyzed tRNA Modifications Regulate Global Protein Expression by Codon-Biased Translation.

    Wenjun Deng

    2015-12-01

    Full Text Available Post-transcriptional modifications of transfer RNAs (tRNAs have long been recognized to play crucial roles in regulating the rate and fidelity of translation. However, the extent to which they determine global protein production remains poorly understood. Here we use quantitative proteomics to show a direct link between wobble uridine 5-methoxycarbonylmethyl (mcm5 and 5-methoxy-carbonyl-methyl-2-thio (mcm5s2 modifications catalyzed by tRNA methyltransferase 9 (Trm9 in tRNAArg(UCU and tRNAGlu(UUC and selective translation of proteins from genes enriched with their cognate codons. Controlling for bias in protein expression and alternations in mRNA expression, we find that loss of Trm9 selectively impairs expression of proteins from genes enriched with AGA and GAA codons under both normal and stress conditions. Moreover, we show that AGA and GAA codons occur with high frequency in clusters along the transcripts, which may play a role in modulating translation. Consistent with these results, proteins subject to enhanced ribosome pausing in yeast lacking mcm5U and mcm5s2U are more likely to be down-regulated and contain a larger number of AGA/GAA clusters. Together, these results suggest that Trm9-catalyzed tRNA modifications play a significant role in regulating protein expression within the cell.

  11. Competing pathways control host resistance to virus via tRNA modification and programmed ribosomal frameshifting.

    Maynard, Nathaniel D; Macklin, Derek N; Kirkegaard, Karla; Covert, Markus W

    2012-01-01

    Viral infection depends on a complex interplay between host and viral factors. Here, we link host susceptibility to viral infection to a network encompassing sulfur metabolism, tRNA modification, competitive binding, and programmed ribosomal frameshifting (PRF). We first demonstrate that the iron-sulfur cluster biosynthesis pathway in Escherichia coli exerts a protective effect during lambda phage infection, while a tRNA thiolation pathway enhances viral infection. We show that tRNA(Lys) uridine 34 modification inhibits PRF to influence the ratio of lambda phage proteins gpG and gpGT. Computational modeling and experiments suggest that the role of the iron-sulfur cluster biosynthesis pathway in infection is indirect, via competitive binding of the shared sulfur donor IscS. Based on the universality of many key components of this network, in both the host and the virus, we anticipate that these findings may have broad relevance to understanding other infections, including viral infection of humans. PMID:22294093

  12. Quantitative single cell monitoring of protein synthesis at subcellular resolution using fluorescently labeled tRNA.

    Barhoom, Sima; Kaur, Jaskiran; Cooperman, Barry S; Smorodinsky, Nechama I; Smilansky, Zeev; Ehrlich, Marcelo; Elroy-Stein, Orna

    2011-10-01

    We have developed a novel technique of using fluorescent tRNA for translation monitoring (FtTM). FtTM enables the identification and monitoring of active protein synthesis sites within live cells at submicron resolution through quantitative microscopy of transfected bulk uncharged tRNA, fluorescently labeled in the D-loop (fl-tRNA). The localization of fl-tRNA to active translation sites was confirmed through its co-localization with cellular factors and its dynamic alterations upon inhibition of protein synthesis. Moreover, fluorescence resonance energy transfer (FRET) signals, generated when fl-tRNAs, separately labeled as a FRET pair occupy adjacent sites on the ribosome, quantitatively reflect levels of protein synthesis in defined cellular regions. In addition, FRET signals enable detection of intra-populational variability in protein synthesis activity. We demonstrate that FtTM allows quantitative comparison of protein synthesis between different cell types, monitoring effects of antibiotics and stress agents, and characterization of changes in spatial compartmentalization of protein synthesis upon viral infection. PMID:21795382

  13. Archease from Pyrococcus abyssi improves substrate specificity and solubility of a tRNA m5C methyltransferase

    Auxilien, Sylvie; El Khadali, Fatima; Rasmussen, Anette;

    2007-01-01

    reading frame (PAB1947), which is shown here to encode a tRNA m(5)C methyltransferase. In vitro, the purified recombinant methyltransferase catalyzes m(5)C formation at several cytosines within tRNAs with preference for C49. The specificity of the methyltransferase is increased by the archease...

  14. A story with a good ending: tRNA 3'-end maturation by CCA-adding enzymes.

    Xiong, Yong; Steitz, Thomas A

    2006-02-01

    CCA-adding enzymes (tRNA nucleotidyltransferases) are responsible for the maturation or repair of the functional 3' end of tRNAs. These enzymes are remarkable because they polymerize the essential nucleotides CCA onto the 3' terminus of tRNA precursors without using a nucleic acid template. Recent crystal structures, plus three decades of enzymology, have revealed the elegant mechanisms by which CCA-adding enzymes achieve their substrate specificity in a nucleic acid template independent fashion. The class I CCA-adding enzyme employs both an arginine sidechain and backbone phosphates of the bound tRNA to recognize incoming nucleotides. It switches from C to A addition through changes in the size and shape of the nucleotide-binding pocket, which is progressively altered by the elongating 3' terminus of the tRNA. By contrast, the class II CCA-adding enzyme uses only amino acid sidechains, which form a protein template for incoming nucleotide selection. PMID:16364630

  15. Electrophoretic mobility shift assays: analysis of tRNA binding to the T box riboswitch antiterminator RNA.

    Anupam, R; Zhou, S; Hines, J V

    2015-01-01

    Changes in electrophoretic mobility upon complex formation with RNA can be used to probe structure-function relationships that are critical for complex formation. Here, we describe the application of this technique to monitor tRNA binding to the T box riboswitch antiterminator RNA. PMID:25352142

  16. Several RNase T2 enzymes function in induced tRNA and rRNA turnover in the ciliate Tetrahymena

    Andersen, Kasper Langebjerg; Collins, Kathleen

    2012-01-01

    RNase T2 enzymes are produced by a wide range of organisms and have been implicated to function in diverse cellular processes, including stress-induced anticodon loop cleavage of mature tRNAs to generate tRNA halves. Here we describe a family of eight RNase T2 genes (RNT2A-RNT2H) in the ciliate...

  17. Evidence that the mitochondrial leucyl tRNA synthetase (LARS2) gene represents a novel type 2 diabetes susceptibility gene

    L.M. 't Hart (Leen); H.A.P. Pols (Huib); T. Hansen (Torben); I. Rietveld (Ingrid); J.M. Dekker (Jacqueline); J.A. Maassen (Johannes); M.G.A.A.M. Nijpels (Giel); G.M.C. Janssen (George); P.P. Arp (Pascal); R.J. Heine (Robert); A.G. Uitterlinden (André); T. Jorgensen (Torben); C.M. van Duijn (Cock); K. Borch-Johnsen; O. Pedersen (Oluf)

    2005-01-01

    textabstractPreviously, we have shown that a mutation in the mitochondrial DNA-encoded tRNA(Leu(UUR)) gene is associated with type 2 diabetes. One of the consequences of this mutation is a reduced aminoacylation of tRNA(Leu(UUR)). In this study, we have examined whether variants in the leucyl tRNA s

  18. The ribosome triggers the stringent response by RelA via a highly distorted tRNA

    Agirrezabala, Xabier; Fernández, Israel S.; Kelley, Ann C.; Cartón, David Gil; Ramakrishnan, Venki; Valle, Mikel

    2013-01-01

    The bacterial stringent response is initiated by RelA and links nutrient starvation with the transcriptional control of genes. Cryo-EM now shows that RelA on the ribosome stabilizes an unusual distorted form of cognate, deacylated tRNA.

  19. Measurement of Acceptor-TΨC Helix Length of tRNA for Terminal A76-Addition by A-Adding Enzyme.

    Yamashita, Seisuke; Martinez, Anna; Tomita, Kozo

    2015-05-01

    The 3'-terminal CCA (C74C75A76-3') of tRNA is required for protein synthesis. In Aquifex aeolicus, the CCA-3' is synthesized by CC-adding and A-adding enzymes, although in most organisms, CCA is synthesized by a single CCA-adding enzyme. The mechanisms by which the A-adding enzyme adds only A76, but not C74C75, onto tRNA remained elusive. The complex structures of the enzyme with various tRNAs revealed the presence of a single tRNA binding site on the enzyme, with the enzyme measuring the acceptor-TΨC helix length of tRNA. The 3'-C75 of tRNA lacking A76 can reach the active site and the size and shape of the nucleotide binding pocket at the insertion stage are suitable for ATP. The 3'-C74 of tRNA lacking C75A76 cannot reach the active site, although CTP or ATP can bind the active pocket. Thus, the A-adding enzyme adds only A76, but not C74C75, onto tRNA. PMID:25914059

  20. RNA molecular turn-over in Tobacco cell cultures. II. Intramolecular and intermolecular differential turn-over of tRNA

    Tobacco cells, exponentially growing in a shaken liquid medium were labeled by addition of [32P]-phosphate during 30 minutes or 4 hours. The tRNA of these cells were extracted and fractionated by reversed phase chromatography (RPC5). The different fractions had the same specific radioactivity after a 4 hours labeling period. When the 32P pulse was shortened to 30 minutes the specific radioactivity of the tail fractions eluted from the RPC5 column chromatography was about two fold that of the head fractions. The fractions eluted from the RPC5 column all belonged to the tRNA population. Their electrophoretic behavior on polyacrylamide gels supplemented with formamide was that of tRNA; the enzymatic acylation of the total tRNA extract and of each fraction were satisfactory; moreover the more heavily labeled fractions were more acylated. Only mature tRNA are responsible for the observed differences between the specific radioactivities of the various tRNA fractions. These differences could not be assigned to the nucleotides of the vCvCvA-OH oligonucleotides 3'-end but were assigned to the transcribed part of the tRNA molecules. These results may be understood according to the hypotheses that either the precursor nucleotide pools of the tRNA incorporated [32P]-phosphate at different rates in different cell compartments, or that some tRNA species, tightly bound to the RPC5 solid phase of the columns, are more rapidly turned over. These explanations do not exclude each other

  1. tRNA Core Hypothesis for the Transition from the RNA World to the Ribonucleoprotein World

    Savio T. de Farias

    2016-03-01

    Full Text Available Herein we present the tRNA core hypothesis, which emphasizes the central role of tRNAs molecules in the origin and evolution of fundamental biological processes. tRNAs gave origin to the first genes (mRNA and the peptidyl transferase center (rRNA, proto-tRNAs were at the core of a proto-translation system, and the anticodon and operational codes then arose in tRNAs molecules. Metabolic pathways emerged from evolutionary pressures of the decoding systems. The transitions from the RNA world to the ribonucleoprotein world to modern biological systems were driven by three kinds of tRNAs transitions, to wit, tRNAs leading to both mRNA and rRNA.

  2. On origin of genetic code and tRNA before translation

    Szathmáry Eörs

    2011-02-01

    Full Text Available Abstract Background Synthesis of proteins is based on the genetic code - a nearly universal assignment of codons to amino acids (aas. A major challenge to the understanding of the origins of this assignment is the archetypal "key-lock vs. frozen accident" dilemma. Here we re-examine this dilemma in light of 1 the fundamental veto on "foresight evolution", 2 modular structures of tRNAs and aminoacyl-tRNA synthetases, and 3 the updated library of aa-binding sites in RNA aptamers successfully selected in vitro for eight amino acids. Results The aa-binding sites of arginine, isoleucine and tyrosine contain both their cognate triplets, anticodons and codons. We have noticed that these cases might be associated with palindrome-dinucleotides. For example, one-base shift to the left brings arginine codons CGN, with CG at 1-2 positions, to the respective anticodons NCG, with CG at 2-3 positions. Formally, the concomitant presence of codons and anticodons is also expected in the reverse situation, with codons containing palindrome-dinucleotides at their 2-3 positions, and anticodons exhibiting them at 1-2 positions. A closer analysis reveals that, surprisingly, RNA binding sites for Arg, Ile and Tyr "prefer" (exactly as in the actual genetic code the anticodon(2-3/codon(1-2 tetramers to their anticodon(1-2/codon(2-3 counterparts, despite the seemingly perfect symmetry of the latter. However, since in vitro selection of aa-specific RNA aptamers apparently had nothing to do with translation, this striking preference provides a new strong support to the notion of the genetic code emerging before translation, in response to catalytic (and possibly other needs of ancient RNA life. Consistently with the pre-translation origin of the code, we propose here a new model of tRNA origin by the gradual, Fibonacci process-like, elongation of a tRNA molecule from a primordial coding triplet and 5'DCCA3' quadruplet (D is a base-determinator to the eventual 76 base

  3. The nucleotide sequence of histidine tRNA gamma of Drosophila melanogaster.

    Altwegg, M.; Kubli, E

    1980-01-01

    The nucleotide sequence of D. melanogaster histidine tRNA gamma was determined to be: pG-G-C-C-G-U-G-A-U-C-G-U-C-psi-A-G-D-G-G-D-D-A-G-G-A-C-C-C-C-A-C-G-psi-U-G-U-G- m1G-C-C-G-U-G-G-U-A-A-C-C-m5C-A-G-G-U-psi-C-G-m1A-A-U-C-C-U-G-G-U-C-A-C-G-G-m5C -A-C-C-AOH. An additional unpaired G is found at the 5' end, and the T in the TpsiC loop is replaced by a U.

  4. Mitochondrial tRNA 5'-editing in Dictyostelium discoideum and Polysphondylium pallidum.

    Abad, Maria G; Long, Yicheng; Kinchen, R Dimitri; Schindel, Elinor T; Gray, Michael W; Jackman, Jane E

    2014-05-30

    Mitochondrial tRNA (mt-tRNA) 5'-editing was first described more than 20 years ago; however, the first candidates for 5'-editing enzymes were only recently identified in a eukaryotic microbe (protist), the slime mold Dictyostelium discoideum. In this organism, eight of 18 mt-tRNAs are predicted to be edited based on the presence of genomically encoded mismatched nucleotides in their aminoacyl-acceptor stem sequences. Here, we demonstrate that mt-tRNA 5'-editing occurs at all predicted sites in D. discoideum as evidenced by changes in the sequences of isolated mt-tRNAs compared with the expected sequences encoded by the mitochondrial genome. We also identify two previously unpredicted editing events in which G-U base pairs are edited in the absence of any other genomically encoded mismatches. A comparison of 5'-editing in D. discoideum with 5'-editing in another slime mold, Polysphondylium pallidum, suggests organism-specific idiosyncrasies in the treatment of U-G/G-U pairs. In vitro activities of putative D. discoideum editing enzymes are consistent with the observed editing reactions and suggest an overall lack of tRNA substrate specificity exhibited by the repair component of the editing enzyme. Although the presence of terminal mismatches in mt-tRNA sequences is highly predictive of the occurrence of mt-tRNA 5'-editing, the variability in treatment of U-G/G-U base pairs observed here indicates that direct experimental evidence of 5'-editing must be obtained to understand the complete spectrum of mt-tRNA editing events in any species. PMID:24737330

  5. Crystal structure of tRNA m1A58 methyltransferase TrmI from Aquifex aeolicus in complex with S-adenosyl-l-methionine

    Kuratani, Mitsuo; Yanagisawa, Tatsuo; Ishii, Ryohei; Matsuno, Michiyo; Si, Shu-Yi; Katsura, Kazushige; Ushikoshi-Nakayama, Ryoko; Shibata, Rie; Shirouzu, Mikako; Bessho, Yoshitaka; Yokoyama, Shigeyuki

    2014-01-01

    The N 1-methyladenosine residue at position 58 of tRNA is found in the three domains of life, and contributes to the stability of the three-dimensional L-shaped tRNA structure. In thermophilic bacteria, this modification is important for thermal adaptation, and is catalyzed by the tRNA m1A58 methyltransferase TrmI, using S-adenosyl-l-methionine (AdoMet) as the methyl donor. We present the 2.2 Å crystal structure of TrmI from the extremely thermophilic bacterium Aquifex aeolicus, in complex wi...

  6. 21 CFR 801.5 - Medical devices; adequate directions for use.

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical devices; adequate directions for use. 801.5 Section 801.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for...

  7. A Drosophila model for mito-nuclear diseases generated by an incompatible interaction between tRNA and tRNA synthetase.

    Holmbeck, Marissa A; Donner, Julia R; Villa-Cuesta, Eugenia; Rand, David M

    2015-08-01

    Communication between the mitochondrial and nuclear genomes is vital for cellular function. The assembly of mitochondrial enzyme complexes, which produce the majority of cellular energy, requires the coordinated expression and translation of both mitochondrially and nuclear-encoded proteins. The joint genetic architecture of this system complicates the basis of mitochondrial diseases, and mutations both in mitochondrial DNA (mtDNA)- and nuclear-encoded genes have been implicated in mitochondrial dysfunction. Previously, in a set of mitochondrial-nuclear introgression strains, we characterized a dual genome epistasis in which a naturally occurring mutation in the Drosophila simulans simw(501) mtDNA-encoded transfer RNA (tRNA) for tyrosine (tRNA(Tyr)) interacts with a mutation in the nuclear-encoded mitochondrially localized tyrosyl-tRNA synthetase from Drosophila melanogaster. Here, we show that the incompatible mitochondrial-nuclear combination results in locomotor defects, reduced mitochondrial respiratory capacity, decreased oxidative phosphorylation (OXPHOS) enzyme activity and severe alterations in mitochondrial morphology. Transgenic rescue strains containing nuclear variants of the tyrosyl-tRNA synthetase are sufficient to rescue many of the deleterious phenotypes identified when paired with the simw(501) mtDNA. However, the severity of this defective mito-nuclear interaction varies across traits and genetic backgrounds, suggesting that the impact of mitochondrial dysfunction might be tissue specific. Because mutations in mitochondrial tRNA(Tyr) are associated with exercise intolerance in humans, this mitochondrial-nuclear introgression model in Drosophila provides a means to dissect the molecular basis of these, and other, mitochondrial diseases that are a consequence of the joint genetic architecture of mitochondrial function. PMID:26035388

  8. Biophysical insights into the intercalative interaction of surfactant cobalt(III) complexes of certain diimine ligands bound to yeast tRNA: Effects of hydrophobicity

    Nagaraj, Karuppiah; Sakthinathan, Subramanian; Arunachalam, Sankaralingam

    2015-08-01

    The interaction of two surfactant cobalt(III) complexes, cis-[Co(ip)2(DA)2](ClO4)3 1 and cis-[Co(dpq)2(DA)2](ClO4)3 2 where ip = imidazo[4,5-f][1,10]phenanthroline and dpq = dipyrido[3,2-d:2‧-3‧-f]quinoxaline with yeast tRNA have been explored by using electronic absorption, competitive binding, electrochemical studies and viscosity measurements. The results suggest that these complexes can bind to tRNA by intercalation. The presence of hydrophobic diimine ligand and the long aliphatic double chains of these complexes facilitate its intercalative interaction with the hydrophobic interior of the tRNA. The extent of tRNA binding of complex 2 has greater affinity than that of complex containing imidazo[4,5-f][1,10]phenanthroline ligands.

  9. PLMItRNA, a database for tRNAs and tRNA genes in plant mitochondria: enlargement and updating

    Volpetti, Vito; Gallerani, Raffaele; De Benedetto, Caterina; Liuni, Sabino; Licciulli, Flavio; Ceci, Luigi R.

    2000-01-01

    The current version of PLMItRNA has been realized to constitute a database for tRNA molecules and genes identified in the mitochondria of all green plants (Viridiplantae). It is the enlargement of a previous database originally restricted to seed plants [Ceci,L.R., Volpicella,M., Liuni,S., Volpetti,V., Licciulli,F. and Gallerani,R. (1999) Nucleic Acids Res., 27, 156–157]. PLMItRNA reports information and multialignments on 254 genes and 16 tRNA molecules detected in 25 higher plants (one bryophyta and 24 vascular plants) and seven green algae. PLMItRNA is accessible via the WWW at http://bio-WWW.ba.cnr.it:8000/srs6/ PMID:10592210

  10. Determination of the Specificity Landscape for Ribonuclease P Processing of Precursor tRNA 5' Leader Sequences.

    Niland, Courtney N; Zhao, Jing; Lin, Hsuan-Chun; Anderson, David R; Jankowsky, Eckhard; Harris, Michael E

    2016-08-19

    Maturation of tRNA depends on a single endonuclease, ribonuclease P (RNase P), to remove highly variable 5' leader sequences from precursor tRNA transcripts. Here, we use high-throughput enzymology to report multiple-turnover and single-turnover kinetics for Escherichia coli RNase P processing of all possible 5' leader sequences, including nucleotides contacting both the RNA and protein subunits of RNase P. The results reveal that the identity of N(-2) and N(-3) relative to the cleavage site at N(1) primarily control alternative substrate selection and act at the level of association not the cleavage step. As a consequence, the specificity for N(-1), which contacts the active site and contributes to catalysis, is suppressed. This study demonstrates high-throughput RNA enzymology as a means to globally determine RNA specificity landscapes and reveals the mechanism of substrate discrimination by a widespread and essential RNA-processing enzyme. PMID:27336323

  11. Impaired protein translation in Drosophila models for Charcot–Marie–Tooth neuropathy caused by mutant tRNA synthetases

    Niehues, Sven; Bussmann, Julia; Steffes, Georg; Erdmann, Ines; Sun, Litao; Wagner, Marina; Wang, Guangxia; Koerdt, Sophia N.; Stum, Morgane; Rajbhandary, Uttam L.; Thomas, Ulrich; Aberle, Hermann; Burgess, Robert W.; Yang, Xiang-Lei; Dieterich, Daniela

    2014-01-01

    Dominant mutations in five tRNA synthetases cause Charcot–Marie–Tooth (CMT) neuropathy, suggesting that altered aminoacylation function underlies the disease. However, previous studies showed that loss of aminoacylation activity is not required to cause CMT. Here we present a Drosophila model for CMT with mutations in glycyl-tRNA synthetase (GARS). Expression of three CMT-mutant GARS proteins induces defects in motor performance and motor and sensory neuron morphology, and shortens lifespan. ...

  12. An entropy based analysis of the relationship between the DOW JONES Index and the TRNA Sentiment series

    Allen, David; McAleer, Michael; Singh, Abhay

    2016-01-01

    textabstractThis paper features an analysis of the relationship between the DOW JONES Industrial Average Index (DJIA) and a sentiment news series using daily data obtained from the Thomson Reuters News Analytics (TRNA)1 provided by SIRCA (The Securities Industry Research Centre of the Asia Pacic). The recent growth in the availability of on-line financial news sources such as internet news and social media sources provides instantaneous access to financial news. Various commercial agencies ha...

  13. Allosteric vs. spontaneous exit-site (E-site) tRNA dissociation early in protein synthesis

    Chen, Chunlai; Stevens, Benjamin; Kaur, Jaskiran; Smilansky, Zeev; Cooperman, Barry S.; Goldman, Yale E.

    2011-01-01

    During protein synthesis, deacylated transfer RNAs leave the ribosome via an exit (E) site after mRNA translocation. How the ribosome regulates tRNA dissociation and whether functional linkages between the aminoacyl (A) and E sites modulate the dynamics of protein synthesis have long been debated. Using single molecule fluorescence resonance energy transfer experiments, we find that, during early cycles of protein elongation, tRNAs are often held in the E site until being allosterically relea...

  14. The tRNA 30-end Processing Enzyme tRNase Z2 Contributes to Chloroplast Biogenesis in Rice

    Tuan Long; Dong Guo; Dong He; Wenjie Shen; Xianghua Li

    2013-01-01

    tRNase Z (TRZ) is a ubiquitous endonuclease that removes the 30-trailer from precursor tRNAs during maturation. In yeast and animals, TRZ regulates the cell cycle via its (t)RNA processing activity;however, its physiological function in higher plants has not been well characterized. This study describes the identification of a rice (Oryza sativa) TRZ2 mutant; plants homozygous for the osatrz2 mutation were albinos with deficient chlorophyll content. A microscopic analysis of the mutant plants revealed that the transition of proplastids to chloroplasts was arrested at an early stage, and the number and size of the plastids in callus cells was substantially decreased. A genetic complementation test and an RNA interference analysis confirmed that disruption of OsaTRZ2 was responsible for the mutant phenotype. OsaTRZ2 is expressed in all rice tissues, but is preferentially expressed in leaves, sheathes, and calli. OsaTRZ2 was subcellularly localized in chloroplasts, and displayed tRNA 30-end processing activity in both in vitro and in vivo assays. In the osatrz2 mutants, transcription of plastid-encoded and nucleus-encoded RNA polymerases was severely reduced and moderately increased, respectively. These results suggest that the tRNA 30 processing activity of OsaTRZ2 contributes to chloroplast biogenesis.

  15. MD Simulations of tRNA and Aminoacyl-tRNA Synthetases: Dynamics, Folding, Binding, and Allostery

    Rongzhong Li

    2015-07-01

    Full Text Available While tRNA and aminoacyl-tRNA synthetases are classes of biomolecules that have been extensively studied for decades, the finer details of how they carry out their fundamental biological functions in protein synthesis remain a challenge. Recent molecular dynamics (MD simulations are verifying experimental observations and providing new insight that cannot be addressed from experiments alone. Throughout the review, we briefly discuss important historical events to provide a context for how far the field has progressed over the past few decades. We then review the background of tRNA molecules, aminoacyl-tRNA synthetases, and current state of the art MD simulation techniques for those who may be unfamiliar with any of those fields. Recent MD simulations of tRNA dynamics and folding and of aminoacyl-tRNA synthetase dynamics and mechanistic characterizations are discussed. We highlight the recent successes and discuss how important questions can be addressed using current MD simulations techniques. We also outline several natural next steps for computational studies of AARS:tRNA complexes.

  16. Gene rearrangements and evolution of tRNA pseudogenes in the mitochondrial genome of the parrotfish (Teleostei: Perciformes: Scaridae).

    Mabuchi, Kohji; Miya, Masaki; Satoh, Takashi P; Westneat, Mark W; Nishida, Mutsumi

    2004-09-01

    Genomic size of animal mitochondrial DNA is usually minimized over time. Thus, when regional duplications occur, they are followed by a rapid elimination of redundant material. In contrast to this general view, we report here long-sustained tRNA pseudogenes in the mitochondrial genome (mitogenome) of teleost fishes of the family Scaridae (parrotfishes). During the course of a molecular phylogenetic study of the suborder Labroidei, we determined the complete nucleotide sequence of the mitogenome for a parrotfish, Chlorurus sordidus, and found a gene rearrangement accompanied by a tRNA pseudogene. In the typical gene order of vertebrates, a tRNA-gene cluster between ND1 and ND2 genes includes tRNA(Ile) (I), tRNA(Gln) (Q), and tRNA(Met) (M) genes in this order (IQM). However, in the mitogenome of the parrotfish, the tRNA(Met) gene was inserted between the tRNA(Ile) and the tRNA(Gln) genes, and the tRNA(Gln) gene was followed by a putative tRNA(Met) pseudogene (psiM). Such a tRNA gene rearrangement including a pseudogene (IMQpsiM) was found in all of the 10 examined species, representing 7 of the 10 currently recognized scarid genera. All sister groups examined (20 species of Labridae and a single species of Odacidae) had the typical gene order of vertebrate mitogenomes. Phylogenetic analysis of the tRNA(Met) genes and the resulting pseudogenes demonstrated that the ancestral tRNA(Met) gene was duplicated in a common ancestor of the parrotfish. Based on the fossil record, these results indicate that the pseudogenes have survived at least 14 million years. Most of the vertebrate mitochondrial gene rearrangements involving the IQM region have held the tRNA(Met) gene just upstream of the ND2 gene, and even in a few exceptional cases, including the present ones, the tRNA pseudogenes have been found in that position. In addition, most of these tRNA(Met) pseudogenes maintained clover-leaf secondary structures, with the remainder sustaining the clover-leaf structure in the

  17. Percentage of Adults with High Blood Pressure Whose Hypertension Is Adequately Controlled

    ... Hypertension is Adequately Controlled Percentage of Adults with High Blood Pressure Whose Hypertension is Adequately Controlled Heart disease and ... Examination Survey. Age Group Percentage of People with High Blood Pressure that is Controlled by Age Group f94q-uyye ...

  18. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  19. 75 FR 69648 - Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers

    2010-11-15

    ... SAFETY BOARD Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers... TO THE SECRETARY OF ENERGY Safety Analysis Requirements for Defining Adequate Protection for the... rule is designed to hold firmly in place. 10 CFR Part 830 imposes a requirement that a...

  20. The Roles of Compensatory Evolution and Constraint in Aminoacyl tRNA Synthetase Evolution.

    Adrion, Jeffrey R; White, P Signe; Montooth, Kristi L

    2016-01-01

    Mitochondrial protein translation requires interactions between transfer RNAs encoded by the mitochondrial genome (mt-tRNAs) and mitochondrial aminoacyl tRNA synthetase proteins (mt-aaRS) encoded by the nuclear genome. It has been argued that animal mt-tRNAs have higher deleterious substitution rates relative to their nuclear-encoded counterparts, the cytoplasmic tRNAs (cyt-tRNAs). This dynamic predicts elevated rates of compensatory evolution of mt-aaRS that interact with mt-tRNAs, relative to aaRS that interact with cyt-tRNAs (cyt-aaRS). We find that mt-aaRS do evolve at significantly higher rates (exemplified by higher dN and dN/dS) relative to cyt-aaRS, across mammals, birds, and Drosophila. While this pattern supports a model of compensatory evolution, the level at which a gene is expressed is a more general predictor of protein evolutionary rate. We find that gene expression level explains 10-56% of the variance in aaRS dN/dS, and that cyt-aaRS are more highly expressed in addition to having lower dN/dS values relative to mt-aaRS, consistent with more highly expressed genes being more evolutionarily constrained. Furthermore, we find no evidence of positive selection acting on either class of aaRS protein, as would be expected under a model of compensatory evolution. Nevertheless, the signature of faster mt-aaRS evolution persists in mammalian, but not bird or Drosophila, lineages after controlling for gene expression, suggesting some additional effect of compensatory evolution for mammalian mt-aaRS. We conclude that gene expression is the strongest factor governing differential amino acid substitution rates in proteins interacting with mitochondrial versus cytoplasmic factors, with important differences in mt-aaRS molecular evolution among taxonomic groups. PMID:26416980

  1. A Hypertension-Associated tRNAAla Mutation Alters tRNA Metabolism and Mitochondrial Function

    Jiang, Pingping; Wang, Meng; Xue, Ling; Xiao, Yun; Yu, Jialing; Wang, Hui; Yao, Juan; Liu, Hao; Peng, Yanyan; Liu, Hanqing; Li, Haiying; Chen, Ye

    2016-01-01

    In this report, we investigated the pathophysiology of a novel hypertension-associated mitochondrial tRNAAla 5655A → G (m.5655A → G) mutation. The destabilization of a highly conserved base pairing (A1-U72) at the aminoacyl acceptor stem by an m.5655A → G mutation altered the tRNAAla function. An in vitro processing analysis showed that the m.5655A → G mutation reduced the efficiency of tRNAAla precursor 5′ end cleavage catalyzed by RNase P. By using cybrids constructed by transferring mitochondria from lymphoblastoid cell lines derived from a Chinese family into mitochondrial DNA (mtDNA)-less (ρo) cells, we showed a 41% reduction in the steady-state level of tRNAAla in mutant cybrids. The mutation caused an improperly aminoacylated tRNAAla, as suggested by aberrantly aminoacylated tRNAAla and slower electrophoretic mobility of mutated tRNA. A failure in tRNAAla metabolism contributed to variable reductions in six mtDNA-encoded polypeptides in mutant cells, ranging from 21% to 37.5%, with an average of a 29.1% reduction, compared to levels of the controls. The impaired translation caused reduced activities of mitochondrial respiration chains. Furthermore, marked decreases in the levels of mitochondrial ATP and membrane potential were observed in mutant cells. These caused increases in the production of reactive oxygen species in the mutant cybrids. The data provide evidence for the association of the tRNAAla 5655A → G mutation with hypertension. PMID:27161322

  2. Deletion analysis of the expression of rRNA genes and associated tRNA genes carried by a lambda transducing bacteriophage

    Transducing phage lambda ilv5 carries genes for rRNA's, spacer tRNA's (tRNA1/sup Ile/ and tRNA/sub 1B//sup Ala/), and two other tRNA's (tRNA1/sup Asp/ and tRNA/sup Trp/). We have isolated a mutant of lambda ilv5, lambda ilv5su7, which carries an amber suppressor mutation in the tRNA/sup Trp/ gene. A series of deletion mutants were isolated from the lambda ilv5su7 phage. Genetic and biochemical analyses of these deletion mutants have confirmed our previous conclusion that the genes for tRNA1/sup Asp/ and tRNA/sup Trp/ located at the distal end of the rRNA operon (rrnC) are cotranscribed with other rRNA genes in that operon. In addition, these deletions were used to define roughly the physical location of the promoter(s) of the rRNA operon carried by the lambda ilv5su7 transducing phage

  3. Auditory information processing during adequate propofol anesthesia monitored by electroencephalogram bispectral index

    C. Kerssens (Chantal); J. Klein (Jan); A. van der Woerd; B. Bonke (Benno)

    2001-01-01

    textabstractMemory for intraoperative events may arise from inadequate anesthesia when the hypnotic state is not continuously monitored. Electroencephalogram bispectral index (BIS) enables monitoring of the hypnotic state and titration of anesthesia to an adequate level

  4. A yeast tRNA mutant that causes pseudohyphal growth exhibits reduced rates of CAG codon translation

    Kemp, Alain J; Betney, Russell; Ciandrini, Luca; Schwenger, Alexandra C M; Romano, M. Carmen; Stansfield, Ian

    2012-01-01

    In Saccharomyces cerevisiae, the SUP70 gene encodes the CAG-decoding tRNAGln CUG. A mutant allele, sup70-65 , induces pseudohyphal growth on rich medium, an inappropriate nitrogen starvation response. This mutant tRNA is also a UAG nonsense suppressor via first base wobble. To investigate the basis of the pseudohyphal phenotype, 10 novel sup70 UAG suppressor alleles were identified, defining positions in the tRNAGln CUG anticodon stem that restrict first base wobble. However, none conferred p...

  5. Use of PCR Amplification of tRNA Gene-Linked Short Tandem Repeats for Genotyping Entamoeba histolytica§

    Ali, Ibne Karim M; Zaki, Mehreen; Clark, C. Graham

    2005-01-01

    We have developed a reliable method for PCR-based genotyping of Entamoeba histolytica based on variation in the numbers of short tandem repeats that are linked to tRNA genes in this species. Species-specific primer pairs were designed that differentiate E. histolytica from E. dispar as well as that reveal intraspecies PCR product length polymorphisms. The primers were tested with samples from different parts of the world, and DNA was extracted from cultured cells as well as liver abscess pus ...

  6. Delivering Access to Safe Drinking Water and Adequate Sanitation in Pakistan

    Faheem Jehangir Khan; Yaser Javed

    2007-01-01

    Provision of safe drinking water, adequate sanitation and personal hygiene are vital for the sustainable environmental conditions and reducing the incidence of diarrhoea, malaria, trachoma, hepatitis A & B and morbidity levels. Not having access to water and sanitation is a courteous expression for a form of deprivation that threatens life, destroys opportunity and undermines human dignity. Thus, investing in the provision of safe water supply and adequate sanitation is not only a development...

  7. Almost equal: Method of adequality from Diophantus to Fermat and beyond

    Katz, Mikhail G.; Schaps, David M.; Shnider, Steven

    2012-01-01

    We analyze some of the main approaches in the literature to the method of `adequality' with which Fermat approached the problems of the calculus, as well as its source in the parisotes of Diophantus, and propose a novel reading thereof. Adequality is a crucial step in Fermat's method of finding maxima, minima, tangents, and solving other problems that a modern mathematician would solve using infinitesimal calculus. The method is presented in a series of short articles in Fermat's collected wo...

  8. Narita Target Heart Rate Equation Underestimates the Predicted Adequate Exercise Level in Sedentary Young Boys

    Siahkouhian, Marefat; Khodadadi, Davar

    2013-01-01

    Purpose Optimal training intensity and the adequate exercise level for physical fitness is one of the most important interests of coaches and sports physiologists. The aim of this study was to investigate the validity of the Narita et al target heart rate equation for the adequate exercise training level in sedentary young boys. Methods Forty two sedentary young boys (19.07±1.16 years) undertook a blood lactate transition threshold maximal treadmill test to volitional exhaustion with continuo...

  9. Current strategies for the restoration of adequate lordosis during lumbar fusion

    Barrey, Cédric; Darnis, Alice

    2015-01-01

    Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 ...

  10. Induction of S-Phase Arrest in Human Glioma Cells by Selenocysteine, a Natural Selenium-Containing Agent Via Triggering Reactive Oxygen Species-Mediated DNA Damage and Modulating MAPKs and AKT Pathways.

    Wang, Kun; Fu, Xiao-Ting; Li, Yuan; Hou, Ya-Jun; Yang, Ming-Feng; Sun, Jing-Yi; Yi, Shu-Ying; Fan, Cun-Dong; Fu, Xiao-Yan; Zhai, Jing; Sun, Bao-Liang

    2016-06-01

    Selenocysteine (SeC) a natural available selenoamino acid exhibits novel anticancer activities against human cancer cell lines. However, the growth inhibitory effect and mechanism of SeC in human glioma cells remain unclear. The present study reveals that SeC time- and dose-dependently inhibited U251 and U87 human glioma cells growth by induction of S-phase cell cycle arrest, followed by the marked decrease of cyclin A. SeC-induced S-phase arrest was achieved by inducing DNA damage through triggering generation of reactive oxygen species (ROS) and superoxide anion, with concomitant increase of TUNEL-positive cells and induction of p21waf1/Cip1 and p53. SeC treatment also caused the activation of p38MAPK, JNK and ERK, and inactivation of AKT. Four inhibitors of MAPKs and AKT pathways further confirmed their roles in SeC-induced S-phase arrest in human glioma cells. Our findings advance the understanding on the molecular mechanisms of SeC in human glioma management. PMID:26846141

  11. Plant tRNA ligases are multifunctional enzymes that have diverged in sequence and substrate specificity from RNA ligases of other phylogenetic origins

    Englert, Markus; Beier, Hildburg

    2005-01-01

    Pre-tRNA splicing is an essential process in all eukaryotes. It requires the concerted action of an endonuclease to remove the intron and a ligase for joining the resulting tRNA halves as studied best in the yeast Saccharomyces cerevisiae. Here, we report the first characterization of an RNA ligase protein and its gene from a higher eukaryotic organism that is an essential component of the pre-tRNA splicing process. Purification of tRNA ligase from wheat germ by successive column chromatograp...

  12. From the Right of Adequate Housing to the Social Right of Adequate Housing%住宅自由权到住宅社会权之流变

    张震

    2015-01-01

    满足公民基本居住需要的住宅权是一项基本权利。面对因住宅价格和质量标准而制约公民住宅权实现的社会现实,有必要在理论上进行检视并提供解决思路。在自由权和社会权划分的理论基础上,我国《宪法》第39条规定的“住宅不受侵犯”具有社会权色彩。而且从权利社会基础和宪法解释功能的双重视角看,住宅社会权在实践中应被侧重。住宅社会权的权利功能以积极受益权为主,消极受益权为次,以国家给付义务的存在为前提。在此基础上,形成对国家权力的规范效力,并具特定内涵。%The right of adequate housing that satisfies the citizens’ basic living needs is a basic right. By the theory of division of freedom and social right, the 39th provision of our Constitution which provides that“the right of adequate housing is free from infringement”is immersed with color of social right. And from the duel perspective of the rights’social basis and the function of Constitu⁃tional interpretation, the social right of adequate housing should be emphasized in practice. The func⁃tion of social right of adequate housing is firstly the positive benefit right, and secondly the negative benefit right, in the premise of the existence of the national duty. On this basis, it forms the regula⁃tory effectiveness to the national power, and contains specific connotation.

  13. A yeast tRNA mutant that causes pseudohyphal growth exhibits reduced rates of CAG codon translation.

    Kemp, Alain J; Betney, Russell; Ciandrini, Luca; Schwenger, Alexandra C M; Romano, M Carmen; Stansfield, Ian

    2013-01-01

    In Saccharomyces cerevisiae, the SUP70 gene encodes the CAG-decoding tRNA(Gln)(CUG). A mutant allele, sup70-65, induces pseudohyphal growth on rich medium, an inappropriate nitrogen starvation response. This mutant tRNA is also a UAG nonsense suppressor via first base wobble. To investigate the basis of the pseudohyphal phenotype, 10 novel sup70 UAG suppressor alleles were identified, defining positions in the tRNA(Gln)(CUG) anticodon stem that restrict first base wobble. However, none conferred pseudohyphal growth, showing altered CUG anticodon presentation cannot itself induce pseudohyphal growth. Northern blot analysis revealed the sup70-65 tRNA(Gln)(CUG) is unstable, inefficiently charged, and 80% reduced in its effective concentration. A stochastic model simulation of translation predicted compromised expression of CAG-rich ORFs in the tRNA(Gln)(CUG)-depleted sup70-65 mutant. This prediction was validated by demonstrating that luciferase expression in the mutant was 60% reduced by introducing multiple tandem CAG (but not CAA) codons into this ORF. In addition, the sup70-65 pseudohyphal phenotype was partly complemented by overexpressing CAA-decoding tRNA(Gln)(UUG), an inefficient wobble-decoder of CAG. We thus show that introducing codons decoded by a rare tRNA near the 5' end of an ORF can reduce eukaryote translational expression, and that the mutant tRNA(CUG)(Gln) constitutive pseudohyphal differentiation phenotype correlates strongly with reduced CAG decoding efficiency. PMID:23146061

  14. Crystallographic capture of a radical S-adenosylmethionine enzyme in the act of modifying tRNA.

    Schwalm, Erica L; Grove, Tyler L; Booker, Squire J; Boal, Amie K

    2016-04-15

    RlmN is a dual-specificity RNA methylase that modifies C2 of adenosine 2503 (A2503) in 23S rRNA and C2 of adenosine 37 (A37) in several Escherichia coli transfer RNAs (tRNAs). A related methylase, Cfr, modifies C8 of A2503 via a similar mechanism, conferring resistance to multiple classes of antibiotics. Here, we report the x-ray structure of a key intermediate in the RlmN reaction, in which a Cys(118)→Ala variant of the protein is cross-linked to a tRNA(Glu)substrate through the terminal methylene carbon of a formerly methylcysteinyl residue and C2 of A37. RlmN contacts the entire length of tRNA(Glu), accessing A37 by using an induced-fit strategy that completely unfolds the tRNA anticodon stem-loop, which is likely critical for recognition of both tRNA and ribosomal RNA substrates. PMID:27081063

  15. Three-Dimensional Algebraic Models of the tRNA Code and 12 Graphs for Representing the Amino Acids

    Marco V. José

    2014-08-01

    Full Text Available Three-dimensional algebraic models, also called Genetic Hotels, are developed to represent the Standard Genetic Code, the Standard tRNA Code (S-tRNA-C, and the Human tRNA code (H-tRNA-C. New algebraic concepts are introduced to be able to describe these models, to wit, the generalization of the 2n-Klein Group and the concept of a subgroup coset with a tail. We found that the H-tRNA-C displayed broken symmetries in regard to the S-tRNA-C, which is highly symmetric. We also show that there are only 12 ways to represent each of the corresponding phenotypic graphs of amino acids. The averages of statistical centrality measures of the 12 graphs for each of the three codes are carried out and they are statistically compared. The phenotypic graphs of the S-tRNA-C display a common triangular prism of amino acids in 10 out of the 12 graphs, whilst the corresponding graphs for the H-tRNA-C display only two triangular prisms. The graphs exhibit disjoint clusters of amino acids when their polar requirement values are used. We contend that the S-tRNA-C is in a frozen-like state, whereas the H-tRNA-C may be in an evolving state.

  16. Fluctuations between multiple EF-G-induced chimeric tRNA states during translocation on the ribosome

    Adio, Sarah; Senyushkina, Tamara; Peske, Frank; Fischer, Niels; Wintermeyer, Wolfgang; Rodnina, Marina V.

    2015-06-01

    The coupled translocation of transfer RNA and messenger RNA through the ribosome entails large-scale structural rearrangements, including step-wise movements of the tRNAs. Recent structural work has visualized intermediates of translocation induced by elongation factor G (EF-G) with tRNAs trapped in chimeric states with respect to 30S and 50S ribosomal subunits. The functional role of the chimeric states is not known. Here we follow the formation of translocation intermediates by single-molecule fluorescence resonance energy transfer. Using EF-G mutants, a non-hydrolysable GTP analogue, and fusidic acid, we interfere with either translocation or EF-G release from the ribosome and identify several rapidly interconverting chimeric tRNA states on the reaction pathway. EF-G engagement prevents backward transitions early in translocation and increases the fraction of ribosomes that rapidly fluctuate between hybrid, chimeric and posttranslocation states. Thus, the engagement of EF-G alters the energetics of translocation towards a flat energy landscape, thereby promoting forward tRNA movement.

  17. Autosomal-Recessive Mutations in the tRNA Splicing Endonuclease Subunit TSEN15 Cause Pontocerebellar Hypoplasia and Progressive Microcephaly.

    Breuss, Martin W; Sultan, Tipu; James, Kiely N; Rosti, Rasim O; Scott, Eric; Musaev, Damir; Furia, Bansri; Reis, André; Sticht, Heinrich; Al-Owain, Mohammed; Alkuraya, Fowzan S; Reuter, Miriam S; Abou Jamra, Rami; Trotta, Christopher R; Gleeson, Joseph G

    2016-07-01

    The tRNA splicing endonuclease is a highly evolutionarily conserved protein complex, involved in the cleavage of intron-containing tRNAs. In human it consists of the catalytic subunits TSEN2 and TSEN34, as well as the non-catalytic TSEN54 and TSEN15. Recessive mutations in the corresponding genes of the first three are known to cause pontocerebellar hypoplasia (PCH) types 2A-C, 4, and 5. Here, we report three homozygous TSEN15 variants that cause a milder version of PCH2. The affected individuals showed progressive microcephaly, delayed developmental milestones, intellectual disability, and, in two out of four cases, epilepsy. None, however, displayed the central visual failure seen in PCH case subjects where other subunits of the TSEN are mutated, and only one was affected by the extensive motor defects that are typical in other forms of PCH2. The three amino acid substitutions impacted the protein level of TSEN15 and the stoichiometry of the interacting subunits in different ways, but all resulted in an almost complete loss of in vitro tRNA cleavage activity. Taken together, our results demonstrate that mutations in any known subunit of the TSEN complex can cause PCH and progressive microcephaly, emphasizing the importance of its function during brain development. PMID:27392077

  18. Structure, Mechanism, and Specificity of a Eukaryal tRNA Restriction Enzyme Involved in Self-Nonself Discrimination

    Anupam K. Chakravarty

    2014-04-01

    Full Text Available tRNA restriction by anticodon nucleases underlies cellular stress responses and self-nonself discrimination in a wide range of taxa. Anticodon breakage inhibits protein synthesis, which, in turn, results in growth arrest or cell death. The eukaryal ribotoxin PaT secreted by Pichia acaciae inhibits growth of Saccharomyces cerevisiae via cleavage of tRNAGln(UUG. We find that recombinant PaT incises a synthetic tRNAGln(UUG stem-loop RNA by transesterification at a single site 3′ of the wobble uridine, yielding 2′,3′-cyclic phosphate and 5′-OH ends. Incision is suppressed by replacement of the wobble nucleobase with adenine or guanine. The crystal structure of PaT reveals a distinctive fold and active site, essential components of which are demonstrated by mutagenesis. Pichia acaciae evades self-toxicity via a distinctive intracellular immunity protein, ImmPaT, which binds PaT and blocks nuclease activity. Our results highlight the evolutionary diversity of tRNA restriction and immunity systems.

  19. The alpha-subunit of Leishmania F1 ATP synthase hydrolyzes ATP in presence of tRNA.

    Goswami, Srikanta; Adhya, Samit

    2006-07-14

    Import of tRNAs into the mitochondria of the kinetoplastid protozoon Leishmania requires the tRNA-dependent hydrolysis of ATP leading to the generation of membrane potential through the pumping of protons. Subunit RIC1 of the inner membrane RNA import complex is a bi-functional protein that is identical to the alpha-subunit of F1F0 ATP synthase and specifically binds to a subset (Type I) of importable tRNAs. We show that recombinant, purified RIC1 is a Type I tRNA-dependent ATP hydrolase. The activity was insensitive to oligomycin, sensitive to mutations within the import signal of the tRNA, and required the cooperative interaction between the ATP-binding and C-terminal domains of RIC1. The ATPase activity of the intact complex was inhibited by anti-RIC1 antibody, while knockdown of RIC1 in Leishmania tropica resulted in deficiency of the tRNA-dependent ATPase activity of the mitochondrial inner membrane. Moreover, RIC1 knockdown extracts failed to generate a membrane potential across reconstituted proteoliposomes, as shown by a rhodamine 123 uptake assay, but activity was restored by adding back purified RIC1. These observations identify RIC1 as a novel form of the F1 ATP synthase alpha-subunit that acts as the major energy transducer for tRNA import. PMID:16735512

  20. Defects in tRNA modification associated with neurological and developmental dysfunctions in Caenorhabditis elegans elongator mutants.

    Changchun Chen

    2009-07-01

    Full Text Available Elongator is a six subunit protein complex, conserved from yeast to humans. Mutations in the human Elongator homologue, hELP1, are associated with the neurological disease familial dysautonomia. However, how Elongator functions in metazoans, and how the human mutations affect neural functions is incompletely understood. Here we show that in Caenorhabditis elegans, ELPC-1 and ELPC-3, components of the Elongator complex, are required for the formation of the 5-carbamoylmethyl and 5-methylcarboxymethyl side chains of wobble uridines in tRNA. The lack of these modifications leads to defects in translation in C. elegans. ELPC-1::GFP and ELPC-3::GFP reporters are strongly expressed in a subset of chemosensory neurons required for salt chemotaxis learning. elpc-1 or elpc-3 gene inactivation causes a defect in this process, associated with a posttranscriptional reduction of neuropeptide and a decreased accumulation of acetylcholine in the synaptic cleft. elpc-1 and elpc-3 mutations are synthetic lethal together with those in tuc-1, which is required for thiolation of tRNAs having the 5'methylcarboxymethyl side chain. elpc-1; tuc-1 and elpc-3; tuc-1 double mutants display developmental defects. Our results suggest that, by its effect on tRNA modification, Elongator promotes both neural function and development.

  1. Minimal Adequate Model of Unemployment Duration in the Post-Crisis Czech Republic

    Adam Čabla

    2016-03-01

    Full Text Available Unemployment is one of the leading economic problems in a developed world. The aim of this paper is to identify the differences in unemployment duration in different strata in the post-crisis Czech Republic via building a minimal adequate model, and to quantify the differences. Data from Labour Force Surveys are used and since they are interval censored in nature, proper metodology must be used. The minimal adequate model is built through the accelerated failure time modelling, maximum likelihood estimates and likelihood ratio tests. Variables at the beginning are sex, marital status, age, education, municipality size and number of persons in a household, containing altogether 29 model parameters. The minimal adequate model contains 5 parameters and differences are found between men and women, the youngest category and the rest and the university educated and the rest. The estimated expected values, variances, medians, modes and 90th percentiles are provided for all subgroups.

  2. The justification of Chinese traditional thought on the right to adequate food

    Du, Gangjian; Sun, Juanjuan

    2010-01-01

    15 pages As declared by the Universal Declaration of Human right, the right to adequate food is one of fundamental contents embodying in the right to a standard of living adequate. However, the recognition of this right has developed progressively and its realization still has a long way to go. Undoubtedly, the guarantee of food supply is a fundamental way to ensure a standard living. In this aspect, early in the pre-Qin period, there have been a great number of schools of thought devoting...

  3. The Cm56 tRNA modification in archaea is catalyzed either by a specific 2′-O-methylase, or a C/D sRNP

    RENALIER, MARIE-HÉLÈNE; JOSEPH, NICOLE; GASPIN, CHRISTINE; THEBAULT, PATRICIA; MOUGIN, ANNIE

    2005-01-01

    We identified the first archaeal tRNA ribose 2′-O-methylase, aTrm56, belonging to the Cluster of Orthologous Groups (COG) 1303 that contains archaeal genes only. The corresponding protein exhibits a SPOUT S-adenosylmethionine (AdoMet)-dependent methyltransferase domain found in bacterial and yeast G18 tRNA 2′-O-methylases (SpoU, Trm3). We cloned the Pyrococcus abyssi PAB1040 gene belonging to this COG, expressed and purified the corresponding protein, and showed that in vitro, it specifically catalyzes the AdoMet-dependent 2′-O-ribose methylation of C at position 56 in tRNA transcripts. This tRNA methylation is present only in archaea, and the gene for this enzyme is present in all the archaeal genomes sequenced up to now, except in the crenarchaeon Pyrobaculum aerophilum. In this archaea, the C56 2′-O-methylation is provided by a C/D sRNP. Our work is the first demonstration that, within the same kingdom, two different mechanisms are used to modify the same nucleoside in tRNAs. PMID:15987815

  4. Role of the primer activation signal in tRNA annealing onto the HIV-1 genome studied by single-molecule FRET microscopy

    N. Beerens (Nancy); M.D.E. Jepsen (Mette); V. Nechyporuk-Zloy (Volodymyr); A.C. Krüger (Asger); J.-L. Darlix (Jean-Luc); J. Kjems (Jørgen); V. Birkedal (Victoria)

    2013-01-01

    textabstractHIV-1 reverse transcription is primed by a cellular tRNAlys3 molecule that binds to the primer binding site (PBS) in the genomic RNA. An additional interaction between the tRNA molecule and the primer activation signal (PAS) is thought to regulate the initiation of reverse transcription.

  5. A novel strategy for the identification of genomic islands by comparative analysis of the contents and contexts of tRNA sites in closely related bacteria.

    Ou, Hong-Yu; Chen, Ling-Ling; Lonnen, James; Chaudhuri, Roy R; Thani, Ali Bin; Smith, Rebecca; Garton, Natalie J; Hinton, Jay; Pallen, Mark; Barer, Michael R; Rajakumar, Kumar

    2006-01-01

    We devised software tools to systematically investigate the contents and contexts of bacterial tRNA and tmRNA genes, which are known insertion hotspots for genomic islands (GIs). The strategy, based on MAUVE-facilitated multigenome comparisons, was used to examine 87 Escherichia coli MG1655 tRNA and tmRNA genes and their orthologues in E.coli EDL933, E.coli CFT073 and Shigella flexneri Sf301. Our approach identified 49 GIs occupying approximately 1.7 Mb that mapped to 18 tRNA genes, missing 2 but identifying a further 30 GIs as compared with Islander [Y. Mantri and K. P. Williams (2004), Nucleic Acids Res., 32, D55-D58]. All these GIs had many strain-specific CDS, anomalous GC contents and/or significant dinucleotide biases, consistent with foreign origins. Our analysis demonstrated marked conservation of sequences flanking both empty tRNA sites and tRNA-associated GIs across all four genomes. Remarkably, there were only 2 upstream and 5 downstream deletions adjacent to the 328 loci investigated. In silico PCR analysis based on conserved flanking regions was also used to interrogate hotspots in another eight completely or partially sequenced E.coli and Shigella genomes. The tools developed are ideal for the analysis of other bacterial species and will lead to in silico and experimental discovery of new genomic islands. PMID:16414954

  6. 21 CFR 514.117 - Adequate and well-controlled studies.

    2010-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... conducted: (i) Placebo concurrent control. The new animal drug is compared with an inactive preparation... control is appropriate when the use of a placebo control or of an untreated concurrent control...

  7. The Relationship between Parental Involvement and Adequate Yearly Progress among Urban, Suburban, and Rural Schools

    Ma, Xin; Shen, Jianping; Krenn, Huilan Y.

    2014-01-01

    Using national data from the 2007-08 School and Staffing Survey, we compared the relationships between parental involvement and school outcomes related to adequate yearly progress (AYP) in urban, suburban, and rural schools. Parent-initiated parental involvement demonstrated significantly positive relationships with both making AYP and staying off…

  8. A Model for Touch Technique and Computation of Adequate Cane Length.

    Plain-Switzer, Karen

    1993-01-01

    This article presents a model for the motion of a long-cane executing the touch technique and presents formulas for the projected length of a cane adequate to protect an individual with blindness against wall-type and pole-type hazards. The paper concludes that the long-cane should reach from the floor to the user's armpit. (JDD)

  9. 76 FR 51041 - Hemoglobin Standards and Maintaining Adequate Iron Stores in Blood Donors; Public Workshop

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Hemoglobin Standards and Maintaining Adequate Iron Stores in... workshop. The Food and Drug Administration (FDA) is announcing a public workshop entitled: ``Hemoglobin... discuss blood donor hemoglobin and hematocrit qualification standards in the United States, its impact...

  10. The Unequal Effect of Adequate Yearly Progress: Evidence from School Visits

    Brown, Abigail B.; Clift, Jack W.

    2010-01-01

    The authors report insights, based on annual site visits to elementary and middle schools in three states from 2004 to 2006, into the incentive effect of the No Child Left Behind Act's requirement that increasing percentages of students make Adequate Yearly Progress (AYP) in every public school. They develop a framework, drawing on the physics…

  11. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    2010-01-01

    ... on problems of animal health, behavior, and well-being is conveyed to the attending veterinarian; (4... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND...

  12. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    2010-01-01

    ... animal health, behavior, and well-being is conveyed to the attending veterinarian; (4) Guidance to... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Attending veterinarian and adequate veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION...

  13. Determinants of prompt and adequate care among presumed malaria cases in a community in eastern Rwanda

    Ingabire, Chantal Marie; Kateera, Fredrick; Hakizimana, Emmanuel; Rulisa, Alexis; Muvunyi, Claude; Mens, Petra; Koenraadt, Sander; Mutesa, Leon; Vugt, Van Michele; Borne, Van Den Bart; Alaii, Jane

    2016-01-01

    Background: In order to understand factors influencing fever/malaria management practices among community-based individuals, the study evaluated psychosocial, socio-demographic and environmental determinants of prompt and adequate healthcare-seeking behaviours. Methods: A quantitative household (

  14. Influenza 2005-2006: vaccine supplies adequate, but bird flu looms.

    Mossad, Sherif B

    2005-11-01

    Influenza vaccine supplies appear to be adequate for the 2005-2006 season, though delivery has been somewhat delayed. However, in the event of a pandemic of avian flu-considered inevitable by most experts, although no one knows when it will happen-the United States would be woefully unprepared. PMID:16315443

  15. Does the new conceptual framework provide adequate concepts for reporting relevant information about performance?

    A. Brouwer; A Faramarzi; M. Hoogendoorn

    2014-01-01

    The basic question we raise in this paper is whether the 2013 Discussion Paper (DP 2013) on the Conceptual Framework provides adequate principles for reporting an entity’s performance and what improvements could be made in light of both user needs and evidence from academic literature. DP 2013 propo

  16. Perceptions of Teachers in Their First Year of School Restructuring: Failure to Make Adequate Yearly Progress

    Moser, Sharon

    2010-01-01

    The 2007-2008 school year marked the first year Florida's Title I schools that did not made Adequate Yearly Progress (AYP) for five consecutive years entered into restructuring as mandated by the "No Child Left Behind Act" of 2001. My study examines the perceptions of teacher entering into their first year of school restructuring due to failure to…

  17. How Much and What Kind? Identifying an Adequate Technology Infrastructure for Early Childhood Education. Policy Brief

    Daugherty, Lindsay; Dossani, Rafiq; Johnson, Erin-Elizabeth; Wright, Cameron

    2014-01-01

    To realize the potential benefits of technology use in early childhood education (ECE), and to ensure that technology can help to address the digital divide, providers, families of young children, and young children themselves must have access to an adequate technology infrastructure. The goals for technology use in ECE that a technology…

  18. Calculation of the Cost of an Adequate Education in Kentucky: A Professional Judgment Approach

    Deborah A. Verstegen

    2004-02-01

    Full Text Available What is an adequate education and how much does it cost? In 1989, Kentucky’s State Supreme Court found the entire system of education unconstitutional-“all of its parts and parcels”. The Court called for all children to have access to an adequate education, one that is uniform and has as its goal the development of seven capacities, including: (i “sufficient oral and written communication skills to enable students to function in a complex and rapidly changing civilization . . . .and (vii sufficient levels of academic or vocational skills to enable public school students to compete favorably with their counterparts in surrounding states, in academics or in the job market”. Now, over a decade later, key questions remain regarding whether these objectives have been fulfilled. This research is designed to calculate the cost of an adequate education by aligning resources to State standards, laws and objectives, using a professional judgment approach. Seven focus groups were convened for this purpose and the scholarly literature was reviewed to provide multiple inputs into study findings. The study produced a per pupil base cost for each of three prototype school districts and an total statewide cost, with the funding gap between existing revenue and the revenue needed for current operations of $1.097 billion per year (2001-02. Additional key resource requirements needed to achieve an adequate education, identified by professional judgment panels, include: (1 extending the school year for students and teachers, (2 adding voluntary half-day preschool for three and four year olds, and (3 raising teacher salaries. This increases the funding gap to $1.23 billion and suggests that significant new funding is required over time if the Commonwealth of Kentucky is to provide an adequate and equitable education of high quality for all children and youth as directed by the State Supreme Court.

  19. Variation in the Spacer Regions Separating tRNA Genes in Renibacterium salmoninarum Distinguishes Recent Clinical Isolates from the Same Location

    Alexander, Sarah M.; Grayson, T. Hilton; Chambers, Edel M.; Cooper, Lynne F.; Barker, Gavin A.; Gilpin, Martyn L.

    2001-01-01

    A means for distinguishing between clinical isolates of Renibacterium salmoninarum that is based on the PCR amplification of length polymorphisms in the tRNA intergenic spacer regions (tDNA-ILPs) was investigated. The method used primers specific to nucleotide sequences of R. salmoninarum tRNA genes and tRNA intergenic spacer regions that had been generated by using consensus tRNA gene primers. Twenty-one PCR products were sequenced from five isolates of R. salmoninarum from the United States, England, and Scotland, and four complete tRNA genes and spacer regions were identified. Sixteen specific PCR primers were designed and tested singly and in all possible pairwise combinations for their potential to discriminate between isolates from recent clinical outbreaks of bacterial kidney disease (BKD) in the United Kingdom. Fourteen of the isolates were cultured from kidney samples taken from fish displaying clinical signs of BKD on five farms, and some of the isolates came from the same farm and at the same time. The tDNA-ILP profiles separated 22 clinical isolates into nine groups and highlighted that some farms may have had more than one source of infection. The grouping of isolates improved on the discriminatory power of previously reported typing methods based on randomly amplified polymorphic DNA analysis and restriction fragment length profiles developed using insertion sequence IS994. Our method enabled us to make divisions between closely related clinical isolates of R. salmoninarum that have identical exact tandem repeat (ETR-A) loci, rRNA intergenic spacer sequences, and IS994 profiles. PMID:11136759

  20. Clues to tRNA Evolution from the Distribution of Class II tRNAs and Serine Codons in the Genetic Code.

    Bernhardt, Harold S

    2016-01-01

    We have previously proposed that tRNA(Gly) was the first tRNA and glycine was the first amino acid incorporated into the genetic code. The next two amino acids incorporated would have been the other two small hydrophilic amino acids serine and aspartic acid, which occurred through the duplication of the tRNA(Gly) sequence, followed by mutation of its anticodon by single C to U transition mutations, possibly through spontaneous deamination. Interestingly, however, tRNA(Ser) has a different structure than most other tRNAs, possessing a long variable arm; because of this tRNA(Ser) is classified as a class II tRNA. Also, serine codons are found not only in the bottom right-hand corner of the genetic code table next to those for glycine and aspartic acid, but also in the top row of the table, next to those for two of the most hydrophobic amino acids, leucine and phenylalanine. In the following, I propose that the class II tRNA structure of tRNA(Ser) and the arrangement of serine codons in the genetic code provide clues to the early evolution of tRNA and the genetic code. In addition, I address Di Giulio's recent criticism of our proposal that tRNA(Gly) was the first tRNA, and discuss how early peptides produced from a restricted amino acid alphabet of glycine, serine and aspartic acid might have possessed proteolytic activity, which is possibly important for the early recycling of amino acid monomers. PMID:26927183

  1. Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA and HIV-1 nef Genes in Escherichia coli.

    Siti Aisyah Mualif

    Full Text Available Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef, HIV-1 p24 (ca, and HIV-1 vif in NiCo21(DE3 E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes.

  2. Variation in the spacer regions separating tRNA genes in Renibacterium salmoninarum distinguishes recent clinical isolates from the same location.

    Alexander, S M; Grayson, T H; Chambers, E M; Cooper, L F; Barker, G A; Gilpin, M L

    2001-01-01

    A means for distinguishing between clinical isolates of Renibacterium salmoninarum that is based on the PCR amplification of length polymorphisms in the tRNA intergenic spacer regions (tDNA-ILPs) was investigated. The method used primers specific to nucleotide sequences of R. salmoninarum tRNA genes and tRNA intergenic spacer regions that had been generated by using consensus tRNA gene primers. Twenty-one PCR products were sequenced from five isolates of R. salmoninarum from the United States, England, and Scotland, and four complete tRNA genes and spacer regions were identified. Sixteen specific PCR primers were designed and tested singly and in all possible pairwise combinations for their potential to discriminate between isolates from recent clinical outbreaks of bacterial kidney disease (BKD) in the United Kingdom. Fourteen of the isolates were cultured from kidney samples taken from fish displaying clinical signs of BKD on five farms, and some of the isolates came from the same farm and at the same time. The tDNA-ILP profiles separated 22 clinical isolates into nine groups and highlighted that some farms may have had more than one source of infection. The grouping of isolates improved on the discriminatory power of previously reported typing methods based on randomly amplified polymorphic DNA analysis and restriction fragment length profiles developed using insertion sequence IS994. Our method enabled us to make divisions between closely related clinical isolates of R. salmoninarum that have identical exact tandem repeat (ETR-A) loci, rRNA intergenic spacer sequences, and IS994 profiles. PMID:11136759

  3. Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA) and HIV-1 nef Genes in Escherichia coli.

    Mualif, Siti Aisyah; Teow, Sin-Yeang; Omar, Tasyriq Che; Chew, Yik Wei; Yusoff, Narazah Mohd; Ali, Syed A

    2015-01-01

    Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW) rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef), HIV-1 p24 (ca), and HIV-1 vif in NiCo21(DE3) E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes. PMID:26147991

  4. Prokaryote phylogeny based on ribosomal proteins and aminoacyl tRNA synthetases by using the compositional distance approach

    WEI; Haibin; QI; Ji; HAO; Bailin

    2004-01-01

    In order to show that the newly developed K-string composition distance method,based on counting oligopeptide frequencies,for inferring phylogenetic relations of prokaryotes works equally well without requiring the whole proteome data,we used all ribosomal proteins and the set of aminoacyl tRNA synthetases for each species.The latter group has been known to yield inconsistent trees if used individually.Our trees are obtained without making any sequence alignment.Altogether 16 Archaea,105 Bacteria and 2 Eucarya are represented on the tree.Most of the lower branchings agree well with the latest,2003,Outline of the second edition of the Bergey's Manual of Systematic Bacteriology and the trees also suggest some relationships among higher taxa.

  5. ALKBH8-mediated formation of a novel diastereomeric pair of wobble nucleosides in mammalian tRNA

    van den Born, E.; Vagbo, C. B.; Songe-Moller, L.;

    2011-01-01

    Mammals have nine different homologues (ALKBH1-9) of the Escherichia coli DNA repair demethylase AlkB. ALKBH2 is a genuine DNA repair enzyme, but the in vivo function of the other ALKBH proteins has remained elusive. It was recently shown that ALKBH8 contains an additional transfer RNA ( tRNA......) methyltransferase domain, which generates the wobble nucleoside 5-methoxycarbonylmethyluridine (mcm(5)U) from its precursor 5-carboxymethyluridine (cm(5)U). In this study, we report that (R)- and (S)-5-methoxycarbonylhydroxymethyluridine (mchm(5)U), hydroxylated forms of mcm(5)U, are present in mammalian tRNA......(UCG)(Arg), and tRNA(UCC)(Gly), respectively, representing the first example of a diastereomeric pair of modified RNA nucleosides. Through in vitro and in vivo studies, we show that both diastereomers of mchm(5)U are generated from mcm(5)U, and that the AlkB domain of ALKBH8 specifically hydroxylates mcm(5)U into...

  6. Interaction of Ru(Ⅱ) Complex with Yeast tRNA Studied by Isothermal Titration Calorimetry

    徐宏; 刘敛洪; 刘志刚; 梁毅; 张鹏; 杜芬; 周兵瑞; 计亮年

    2005-01-01

    The interaction of metal complex with RNA has been studied by isothermal titration calorimetry (ITC) for the first time. ITC experiments show that complex [Ru(phen)2MPIP]2+ {phen= 1,10-phenanthroline, MP[P-2-(4-methylphenyl)imidazo[4,5-f]-1, 10-phenanthroline} interacts with yeast tRNA in terms of a model for a singleset of identical sites through intercalation, which is consistent with our previous observation obtained from spectroscopic methods, and this binding process was driven by a moderately favorable enthalpy decrease in combination with a moderately favorable entropy increase, suggesting that ITC is an effective method for deep studying the interactions of metal complexes with RNA.

  7. The defective expression of gtpbp3 related to tRNA modification alters the mitochondrial function and development of zebrafish.

    Chen, Danni; Li, Feng; Yang, Qingxian; Tian, Miao; Zhang, Zengming; Zhang, Qinghai; Chen, Ye; Guan, Min-Xin

    2016-08-01

    Human mitochondrial DNA (mtDNA) mutations have been associated with a wide spectrum of clinical abnormalities. However, nuclear modifier gene(s) modulate the phenotypic expression of pathogenic mtDNA mutations. In our previous investigation, we identified the human GTPBP3 related to mitochondrial tRNA modification, acting as a modifier to influence of deafness-associated mtDNA mutation. Mutations in GTPBP3 have been found to be associated with other human diseases. However, the pathophysiology of GTPBP3-associated disorders is still not fully understood. Here, we reported the generation and characterization of Gtpbp3 depletion zebrafish model using antisense morpholinos. Zebrafish gtpbp3 has three isoforms localized at mitochondria. Zebrafish gtpbp3 is expressed at various embryonic stages and in multiple tissues. In particular, the gtpbp3 was expressed more abundantly in adult zebrafish ovary and testis. The expression of zebrafish gtpbp3 can functionally restore the growth defects caused by the mss1/gtpbp3 mutation in yeast. A marked decrease of mitochondrial ATP generation accompanied by increased levels of apoptosis and reactive oxygen species were observed in gtpbp3 knockdown zebrafish embryos. The Gtpbp3 morphants exhibited defective in embryonic development including bleeding, melenin, oedema and curved tails within 5days post fertilization, as compared with uninjected controls. The co-injection of wild type gtpbp3 mRNA partially rescued these defects in Gtpbp3 morphants. These data suggest that zebrafish Gtpbp3 is a structural and functional homolog of human and yeast GTPBP3. The mitochondrial dysfunction caused by defective Gtpbp3 may alter the embryonic development in the zebrafish. In addition, this zebrafish model of mitochondrial disease may provide unique opportunities for studying defective tRNA modification, mitochondrial biogenesis, and pathophysiology of mitochondrial disorders. PMID:27184967

  8. Role of codon usage and tRNA changes in rat cytomegalovirus latency and (re)activation.

    Kanduc, Darja

    2016-06-01

    Herpesviruses can remain in their hosts by establishing a latent infection with a low pattern of viral gene expression. Passage from latency to reactivation may occur under particular conditions such as immunosuppressive treatments or during fetal development, and often is accompanied by heavy pathologic sequelae. To investigate the molecular basis underlying herpesvirus latency and (re)activation, codon usage of rat cytomegalovirus was comparatively analyzed with respect to the rat codon usage. Two major points stand out as follows: (i) six codons - GCG (Ala), CCG (Pro), CGG (Arg), CGC (Arg), TCG (Ser), and ACG (Thr) - are rare in rat genes and intensively used in rat cytomegalovirus coding sequences; (ii) in many instances, the codons seldom used by the host are clustered along viral sequences coding for single amino acid repeats such as poly-Ala and poly-Thr stretches. The results indicate that rare host codons and their iteration along viral sequences might represent major constraints that lock rat cytomegalovirus translation in its host during the viral latent phase. Consequently, the data also suggest a link between rat cytomegalovirus quiescence/activation and the functional tRNA coadaptation phenomenon. Indeed, increases in minor tRNA species corresponding to rare rat codons mark rat cell proliferation and might rescue difficult viral translational contexts. Ala isoaccepting-tRNA (CGC) is reported as an example. On the whole, the present findings may contribute to explain how the molecular mechanisms that normally control host gene expression can silence/(re)activate viral gene expression, and might address research toward new approaches in anti-viral therapeutics. PMID:26875974

  9. Global translational impacts of the loss of the tRNA modification t6A in yeast

    Patrick C. Thiaville

    2015-12-01

    Full Text Available The universal tRNA modification t6A is found at position 37 of nearly all tRNAs decoding ANN codons. The absence of t6A37 leads to severe growth defects in baker’s yeast, phenotypes similar to those caused by defects in mcm5s2U34 synthesis. Mutants in mcm5s2U34 can be suppressed by overexpression of tRNALysUUU, but we show t6A phenotypes could not be suppressed by expressing any individual ANN decoding tRNA, and t6A and mcm5s2U are not determinants for each other’s formation. Our results suggest that t6A deficiency, like mcm5s2U deficiency, leads to protein folding defects, and show that the absence of t6A led to stress sensitivities (heat, ethanol, salt and sensitivity to TOR pathway inhibitors. Additionally, L-homoserine suppressed the slow growth phenotype seen in t6A-deficient strains, and proteins aggregates and Advanced Glycation End-products (AGEs were increased in the mutants. The global consequences on translation caused by t6A absence were examined by ribosome profiling. Interestingly, the absence of t6A did not lead to global translation defects, but did increase translation initiation at upstream non-AUG codons and increased frame-shifting in specific genes. Analysis of codon occupancy rates suggests that one of the major roles of t6A is to homogenize the process of elongation by slowing the elongation rate at codons decoded by high abundance tRNAs and I34:C3 pairs while increasing the elongation rate of rare tRNAs and G34:U3 pairs. This work reveals that the consequences of t6A absence are complex and multilayered and has set the stage to elucidate the molecular basis of the observed phenotypes.

  10. Peptidyl transferase antibiotics perturb the relative positioning of the 3'-terminal adenosine of P/P'-site-bound tRNA and 23S rRNA in the ribosome

    Kirillov, S V; Porse, B T; Garrett, R A

    1999-01-01

    A range of antibiotic inhibitors that act within the peptidyl transferase center of the ribosome were examined for their capacity to perturb the relative positioning of the 3' end of P/P'-site-bound tRNA and the Escherichia coli ribosome. The 3'-terminal adenosines of deacylated tRNA and N......-ribosome complexes. It is concluded that the antibiotics perturb the relative positioning of the 3' end of the P/P'-site-bound tRNA and the peptidyl transferase loop region of 23S rRNA....

  11. Enhancing entrepreneurship development in Bosnia and Herzegovina through adequate governmental financial support

    Umihanić, Bahrija; Đonlagić, Sabina; Piplica, Damir

    2016-01-01

    Entrepreneurship and SME sector is extremely important for general economic development in Bosnia and Herzegovina. In order to enhance further development of the SME sector adequate sources of financing for businesses need to be available and accessible. Entrepreneurs and owners of small and medium businesses in Bosnia and Herzegovina are facing certain challenges in obtaining finances. The issue of accessing sources of finance for SMEs in this country has remained problematic for years. Many...

  12. Impact of adequate empirical combination therapy on mortality from bacteremic Pseudomonas aeruginosa pneumonia

    Park So-Youn; Park Hyun; Moon Song; Park Ki-Ho; Chong Yong; Kim Mi-Na; Kim Sung-Han; Lee Sang-Oh; Kim Yang; Woo Jun; Choi Sang-Ho

    2012-01-01

    Abstract Background Pseudomonas aeruginosa has gained an increasing amount of attention in the treatment of patients with pneumonia. However, the benefit of empirical combination therapy for pneumonia remains unclear. We evaluated the effects of adequate empirical combination therapy and multidrug-resistance in bacteremic Pseudomonas pneumonia on the mortality. Methods A retrospective cohort study was performed at the 2,700-bed tertiary care university hospital. We reviewed the medical record...

  13. Evaluation of lymph node numbers for adequate staging of Stage II and III colon cancer

    Bumpers Harvey L

    2011-05-01

    Full Text Available Abstract Background Although evaluation of at least 12 lymph nodes (LNs is recommended as the minimum number of nodes required for accurate staging of colon cancer patients, there is disagreement on what constitutes an adequate identification of such LNs. Methods To evaluate the minimum number of LNs for adequate staging of Stage II and III colon cancer, 490 patients were categorized into groups based on 1-6, 7-11, 12-19, and ≥ 20 LNs collected. Results For patients with Stage II or III disease, examination of 12 LNs was not significantly associated with recurrence or mortality. For Stage II (HR = 0.33; 95% CI, 0.12-0.91, but not for Stage III patients (HR = 1.59; 95% CI, 0.54-4.64, examination of ≥20 LNs was associated with a reduced risk of recurrence within 2 years. However, examination of ≥20 LNs had a 55% (Stage II, HR = 0.45; 95% CI, 0.23-0.87 and a 31% (Stage III, HR = 0.69; 95% CI, 0.38-1.26 decreased risk of mortality, respectively. For each six additional LNs examined from Stage III patients, there was a 19% increased probability of finding a positive LN (parameter estimate = 0.18510, p Conclusions Thus, the 12 LN cut-off point cannot be supported as requisite in determining adequate staging of colon cancer based on current data. However, a minimum of 6 LNs should be examined for adequate staging of Stage II and III colon cancer patients.

  14. The definition of rural area as a primary solution of its adequate development

    Ivana Faltová Leitmanová; Eva Cudlínová; Milan Jílek; Renata Klufová; Ladislav Rolínek

    2009-01-01

    The realistic approach to the rural development requires primarily a consensual definition of a rural area. The selection of tools to be applied and measures to be taken to influence rural areas as well as the setting up the institutional framework would be difficult without defining the object of interest. The adequate definition of rural areas is therefore one of essential prerequisites for the effective resource allocation within the rural development policy.

  15. Towards the Full Realization of the Human Right to Adequate Food and Nutrition*

    Flavio Luiz Schieck Valente

    2014-01-01

    This article describes the conceptual evolution of the right to food into its current denomination as human right to adequate food and nutrition in the broader context of the indivisibility of human rights, women’s rights and food sovereignty. It also explores the challenges and opportunities provided by the Second International Conference on Nutrition and describes the political foundations of civil society’s engagement in the preparation and planned follow-up of the conference.

  16. Evaluating Random Mutant Selection at Class-Level in Projects with Non-Adequate Test Suites

    Parsai, Ali; Murgia, Alessandro; Demeyer, Serge

    2016-01-01

    Mutation testing is a standard technique to evaluate the quality of a test suite. Due to its computationally intensive nature, many approaches have been proposed to make this technique feasible in real case scenarios. Among these approaches, uniform random mutant selection has been demonstrated to be simple and promising. However, works on this area analyze mutant samples at project level mainly on projects with adequate test suites. In this paper, we fill this lack of empirical validation by...

  17. Ensuring adequate orientation for a new employee : case company Nestlé

    Ashtiani, Shilan

    2015-01-01

    The following thesis will concentrate on the importance of ensuring adequate orientation throughout the recruitment process and after. A new employee orientation (NEO) plan is consisted of different areas and stages to be recognized, analyzed and implemented at the factory of Nestlé. The goal for every company nowadays is to make a new employee a valued resource for their profitability. This research was commissioned by Nestlé Oy, Turku factory. The concept of new employee orientation (NE...

  18. Self-esteem, social support, and satisfaction differences in women with adequate and inadequate prenatal care.

    Higgins, P; Murray, M L; Williams, E M

    1994-03-01

    This descriptive, retrospective study examined levels of self-esteem, social support, and satisfaction with prenatal care in 193 low-risk postpartal women who obtained adequate and inadequate care. The participants were drawn from a regional medical center and university teaching hospital in New Mexico. A demographic questionnaire, the Coopersmith self-esteem inventory, the personal resource questionnaire part 2, and the prenatal care satisfaction inventory were used for data collection. Significant differences were found in the level of education, income, insurance, and ethnicity between women who received adequate prenatal care and those who received inadequate care. Women who were likely to seek either adequate or inadequate prenatal care were those whose total family income was $10,000 to $19,999 per year and high school graduates. Statistically significant differences were found in self-esteem, social support, and satisfaction between the two groups of women. Strategies to enhance self-esteem and social support have to be developed to reach women at risk for receiving inadequate prenatal care. PMID:8155221

  19. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    Emma Jones

    2016-05-01

    Full Text Available Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC, a fingerpick blood sample for Thyroglobulin (Tg concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ. The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415 was 116 μg/L (females 106 μg/L, males 131 μg/L indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L. The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001 and ethnicity (p = 0.006. The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate.

  20. The Nigerian health care system: Need for integrating adequate medical intelligence and surveillance systems

    Menizibeya Osain Welcome

    2011-01-01

    Full Text Available Objectives : As an important element of national security, public health not only functions to provide adequate and timely medical care but also track, monitor, and control disease outbreak. The Nigerian health care had suffered several infectious disease outbreaks year after year. Hence, there is need to tackle the problem. This study aims to review the state of the Nigerian health care system and to provide possible recommendations to the worsening state of health care in the country. To give up-to-date recommendations for the Nigerian health care system, this study also aims at reviewing the dynamics of health care in the United States, Britain, and Europe with regards to methods of medical intelligence/surveillance. Materials and Methods : Databases were searched for relevant literatures using the following keywords: Nigerian health care, Nigerian health care system, and Nigerian primary health care system. Additional keywords used in the search were as follows: United States (OR Europe health care dynamics, Medical Intelligence, Medical Intelligence systems, Public health surveillance systems, Nigerian medical intelligence, Nigerian surveillance systems, and Nigerian health information system. Literatures were searched in scientific databases Pubmed and African Journals OnLine. Internet searches were based on Google and Search Nigeria. Results : Medical intelligence and surveillance represent a very useful component in the health care system and control diseases outbreak, bioattack, etc. There is increasing role of automated-based medical intelligence and surveillance systems, in addition to the traditional manual pattern of document retrieval in advanced medical setting such as those in western and European countries. Conclusion : The Nigerian health care system is poorly developed. No adequate and functional surveillance systems are developed. To achieve success in health care in this modern era, a system well grounded in routine

  1. Determining Adequate Margins in Head and Neck Cancers: Practice and Continued Challenges.

    Williams, Michelle D

    2016-09-01

    Margin assessment remains a critical component of oncologic care for head and neck cancer patients. As an integrated team, both surgeons and pathologists work together to assess margins in these complex patients. Differences in method of margin sampling can impact obtainable information and effect outcomes. Additionally, what distance is an "adequate or clear" margin for patient care continues to be debated. Ultimately, future studies and potentially secondary modalities to augment pathologic assessment of margin assessment (i.e., in situ imaging or molecular assessment) may enhance local control in head and neck cancer patients. PMID:27469263

  2. Family Structure Types and Adequate Utilization of Antenatal Care in Kenya.

    Owili, Patrick Opiyo; Muga, Miriam Adoyo; Chou, Yiing-Jenq; Hsu, Yi-Hsin Elsa; Huang, Nicole; Chien, Li-Yin

    2016-01-01

    Features of the health care delivery system may not be the only expounding factors of adequate utilization of antenatal care among women. Other social factors such as the family structure and its environment contribute toward pregnant women's utilization of antenatal care. An understanding of how women in different family structure types and social groups use basic maternal health services is important toward developing and implementing maternal health care policy in the post-Millennium Development Goal era, especially in the sub-Saharan Africa where maternal mortality still remains high. PMID:27214674

  3. Sequence Classification: 54906 [

    Full Text Available -tRNA synthetase ; also charges selenocystein tRNA with serine || http://www.ncbi.nlm.nih.gov/protein/50085962 ... ...Non-TMB Non-TMH Non-TMB Non-TMB Non-TMB Non-TMB >gi|50085962|ref|YP_047472.1| seryl

  4. Sequence Classification: 288478 [

    Full Text Available e tRNA synthetase; also charges selenocystein tRNA with serine || http://www.ncbi.nlm.nih.gov/protein/16128860 ... ...Non-TMB Non-TMH Non-TMB Non-TMB Non-TMB Non-TMB >gi|16128860|ref|NP_415413.1| serin

  5. Sequence Classification: 292928 [

    Full Text Available e tRNA synthetase; also charges selenocystein tRNA with serine || http://www.ncbi.nlm.nih.gov/protein/15800756 ... ...Non-TMB Non-TMH Non-TMB Non-TMB Non-TMB Non-TMB >gi|15800756|ref|NP_286770.1| serin

  6. Elongation in translation as a dynamic interaction among the ribosome, tRNA, and elongation factors EF-G and EF-Tu.

    Agirrezabala, Xabier; Frank, Joachim

    2009-08-01

    The ribosome is a complex macromolecular machine that translates the message encoded in the messenger RNA and synthesizes polypeptides by linking the individual amino acids carried by the cognate transfer RNAs (tRNAs). The protein elongation cycle, during which the tRNAs traverse the ribosome in a coordinated manner along a path of more than 100 A, is facilitated by large-scale rearrangements of the ribosome. These rearrangements go hand in hand with conformational changes of tRNA as well as elongation factors EF-Tu and EF-G - GTPases that catalyze tRNA delivery and translocation, respectively. This review focuses on the structural data related to the dynamics of the ribosomal machinery, which are the basis, in conjunction with existing biochemical, kinetic, and fluorescence resonance energy transfer data, of our knowledge of the decoding and translocation steps of protein elongation. PMID:20025795

  7. Defective i6A37 modification of mitochondrial and cytosolic tRNAs results from pathogenic mutations in TRIT1 and its substrate tRNA.

    John W Yarham

    2014-06-01

    Full Text Available Identifying the genetic basis for mitochondrial diseases is technically challenging given the size of the mitochondrial proteome and the heterogeneity of disease presentations. Using next-generation exome sequencing, we identified in a patient with severe combined mitochondrial respiratory chain defects and corresponding perturbation in mitochondrial protein synthesis, a homozygous p.Arg323Gln mutation in TRIT1. This gene encodes human tRNA isopentenyltransferase, which is responsible for i6A37 modification of the anticodon loops of a small subset of cytosolic and mitochondrial tRNAs. Deficiency of i6A37 was previously shown in yeast to decrease translational efficiency and fidelity in a codon-specific manner. Modelling of the p.Arg323Gln mutation on the co-crystal structure of the homologous yeast isopentenyltransferase bound to a substrate tRNA, indicates that it is one of a series of adjacent basic side chains that interact with the tRNA backbone of the anticodon stem, somewhat removed from the catalytic center. We show that patient cells bearing the p.Arg323Gln TRIT1 mutation are severely deficient in i6A37 in both cytosolic and mitochondrial tRNAs. Complete complementation of the i6A37 deficiency of both cytosolic and mitochondrial tRNAs was achieved by transduction of patient fibroblasts with wild-type TRIT1. Moreover, we show that a previously-reported pathogenic m.7480A>G mt-tRNASer(UCN mutation in the anticodon loop sequence A36A37A38 recognised by TRIT1 causes a loss of i6A37 modification. These data demonstrate that deficiencies of i6A37 tRNA modification should be considered a potential mechanism of human disease caused by both nuclear gene and mitochondrial DNA mutations while providing insight into the structure and function of TRIT1 in the modification of cytosolic and mitochondrial tRNAs.

  8. Secondary structure and feature of mitochondrial tRNA genes of the Ussurian tube-nosed bat Murina ussuriensis (Chiroptera: Vespertilionidae)

    Kwang Bae Yoon; Yung Chul Park

    2015-01-01

    The complete mitogenome (NC_021119) of the Ussurian tube-nosed bat Murina ussuriensis (Chiroptera: Vespertilionidae) was annotated and characterized in our recent publication (http://www.ncbi.nlm.nih.gov/nuccore/NC_021119). Here we provide additional information on methods in detail for obtaining the complete sequence of M. ussuriensis mitogenome. In addition, we describe characteristics of 22 tRNA genes and secondary structure and feature of 22 tRNAs of M. ussuriensis mitogenome.

  9. Secondary structure and feature of mitochondrial tRNA genes of the Ussurian tube-nosed bat Murina ussuriensis (Chiroptera: Vespertilionidae

    Kwang Bae Yoon

    2015-09-01

    Full Text Available The complete mitogenome (NC_021119 of the Ussurian tube-nosed bat Murina ussuriensis (Chiroptera: Vespertilionidae was annotated and characterized in our recent publication (http://www.ncbi.nlm.nih.gov/nuccore/NC_021119. Here we provide additional information on methods in detail for obtaining the complete sequence of M. ussuriensis mitogenome. In addition, we describe characteristics of 22 tRNA genes and secondary structure and feature of 22 tRNAs of M. ussuriensis mitogenome.

  10. Decreased aminoacylation in pathology-related mutants of mitochondrial tRNATyr is associated with structural perturbations in tRNA architecture

    Bonnefond, Luc; Florentz, Catherine; GIEGÉ, RICHARD; Rudinger-Thirion, Joëlle

    2008-01-01

    A growing number of human pathologies are ascribed to mutations in mitochondrial tRNA genes. Here, we report biochemical investigations on three mt-tRNATyr molecules with point substitutions associated with diseases. The mutations occur in the atypical T- and D-loops at positions homologous to those involved in the tertiary interaction network of canonical tRNAs. They do not correspond to tyrosine identity positions and likely do not contact the mitochondrial tyrosyl-tRNA synthetase during th...

  11. An uncommon clinical presentation of relapsing dilated cardiomyopathy with identification of sequence variations in MYNPC3, KCNH2 and mitochondrial tRNA cysteine

    Guillen Sacoto, Maria J.; Chapman, Kimberly A; Deneen Heath; Mary Beth Seprish; Zand, Dina J.

    2015-01-01

    We describe a young girl with dilated cardiomyopathy, long QT syndrome, and possible energy deficiency. Two major sequence changes were identified by whole exome sequencing (WES) and mitochondrial DNA analysis that were interpreted as potentially causative. Changes were identified in the KCNH2 gene and mitochondrial tRNA for cysteine. A variation was also seen in MYPBC3. Since the launch of WES as a clinically available technology in 2010, there has been concern regarding the identification o...

  12. Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA) and HIV-1 nef Genes in Escherichia coli

    Mualif, Siti Aisyah; Teow, Sin-Yeang; Omar, Tasyriq Che; Chew, Yik Wei; Yusoff, Narazah Mohd; Syed A. Ali

    2015-01-01

    Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expres...

  13. Response of cotton genotypes to boron under-b-adequate conditions

    Balanced boron (B) application is well-known to enhance the cotton production; however, the narrow range between B-deficiency and toxicity levels makes it difficult to manage. Cotton genotypes extensively differ in their response to B requirements. The adequate dose of B for one genotype may be insufficient or even toxic to other genotype. The effects of boron (B) on seed cotton yield and its various yield associated traits were studied on 10 cotton genotypes of Pakistan. The pot studies were undertaken to categorize cotton genotypes using B-deficient (control) and B-adequate (2.0 kg B ha-1) levels arranged in CRD with four repeats. The results indicated that the seed cotton yield, yield attributes and B-uptake of genotypes were comparatively decreased in B-deficient stressed treatment. Genotype NIA-Ufaq exhibited wide range of adaptation and ranked as efficient-responsive, as it produced higher seed cotton yield under both B-regimes. SAU-2 and CIM-506 were highly-efficient and remaining all genotypes were medium-efficient. Genotype Sindh-1 produced low seed cotton yield under B deficient condition and ranked as low-efficient. B-efficient cotton genotypes can be grown in B deficient soils without B application. (author)

  14. Incentives for an adequate, economic and reliable Swiss transmission grid. Final version

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) discusses incentives necessary for the implementation of an adequate, economic and reliable Swiss electricity transmission grid. As Switzerland moves towards a more liberalised and competitive electricity market, an essential task of policy makers will be to ensure that incentives are in place for the construction, maintenance and operation of adequate, economic and reliable transmission infrastructure. As well as continuing to serve the domestic market, the location of Switzerland at the centre of Europe also means that policy should embrace opportunities in servicing the developing European Internal Market by providing transit and other services. Topics discussed include the economic evaluation of transmission investment proposals, regulated transmission investment, investments in transmission lines by power merchants, power auctions and congestion management as well as inter-TSO compensation mechanisms. European regulations and practice are discussed as are access questions and transmission charges. Developments in interconnection management and harmonisation are examined. The particular characteristics of the Swiss energy system, its prices and its legal frameworks are discussed. Cross-border trading and security of supply are also discussed

  15. Incentives for an adequate, economic and reliable Swiss transmission grid. Final version

    Twomey, P.; Neuhoff, K.; Newbery, D.

    2006-11-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) discusses incentives necessary for the implementation of an adequate, economic and reliable Swiss electricity transmission grid. As Switzerland moves towards a more liberalised and competitive electricity market, an essential task of policy makers will be to ensure that incentives are in place for the construction, maintenance and operation of adequate, economic and reliable transmission infrastructure. As well as continuing to serve the domestic market, the location of Switzerland at the centre of Europe also means that policy should embrace opportunities in servicing the developing European Internal Market by providing transit and other services. Topics discussed include the economic evaluation of transmission investment proposals, regulated transmission investment, investments in transmission lines by power merchants, power auctions and congestion management as well as inter-TSO compensation mechanisms. European regulations and practice are discussed as are access questions and transmission charges. Developments in interconnection management and harmonisation are examined. The particular characteristics of the Swiss energy system, its prices and its legal frameworks are discussed. Cross-border trading and security of supply are also discussed

  16. Identification and sequence analysis of metazoan tRNA 3'-end processing enzymes tRNase Zs.

    Zhikang Wang

    Full Text Available tRNase Z is the endonuclease responsible for removing the 3'-trailer sequences from precursor tRNAs, a prerequisite for the addition of the CCA sequence. It occurs in the short (tRNase Z(S and long (tRNase Z(L forms. Here we report the identification and sequence analysis of candidate tRNase Zs from 81 metazoan species. We found that the vast majority of deuterostomes, lophotrochozoans and lower metazoans have one tRNase Z(S and one tRNase Z(L genes, whereas ecdysozoans possess only a single tRNase Z(L gene. Sequence analysis revealed that in metazoans, a single nuclear tRNase Z(L gene is likely to encode both the nuclear and mitochondrial forms of tRNA 3'-end processing enzyme through mechanisms that include alternative translation initiation from two in-frame start codons and alternative splicing. Sequence conservation analysis revealed a variant PxKxRN motif, PxPxRG, which is located in the N-terminal region of tRNase Z(Ss. We also identified a previously unappreciated motif, AxDx, present in the C-terminal region of both tRNase Z(Ss and tRNase Z(Ls. The AxDx motif consisting mainly of a very short loop is potentially close enough to form hydrogen bonds with the loop containing the PxKxRN or PxPxRG motif. Through complementation analysis, we demonstrated the likely functional importance of the AxDx motif. In conclusion, our analysis supports the notion that in metazoans a single tRNase Z(L has evolved to participate in both nuclear and mitochondrial tRNA 3'-end processing, whereas tRNase Z(S may have evolved new functions. Our analysis also unveils new evolutionarily conserved motifs in tRNase Zs, including the C-terminal AxDx motif, which may have functional significance.

  17. Crystal structure of tRNA m(1)A58 methyltransferase TrmI from Aquifex aeolicus in complex with S-adenosyl-L-methionine.

    Kuratani, Mitsuo; Yanagisawa, Tatsuo; Ishii, Ryohei; Matsuno, Michiyo; Si, Shu-Yi; Katsura, Kazushige; Ushikoshi-Nakayama, Ryoko; Shibata, Rie; Shirouzu, Mikako; Bessho, Yoshitaka; Yokoyama, Shigeyuki

    2014-09-01

    The N (1)-methyladenosine residue at position 58 of tRNA is found in the three domains of life, and contributes to the stability of the three-dimensional L-shaped tRNA structure. In thermophilic bacteria, this modification is important for thermal adaptation, and is catalyzed by the tRNA m(1)A58 methyltransferase TrmI, using S-adenosyl-L-methionine (AdoMet) as the methyl donor. We present the 2.2 Å crystal structure of TrmI from the extremely thermophilic bacterium Aquifex aeolicus, in complex with AdoMet. There are four molecules per asymmetric unit, and they form a tetramer. Based on a comparison of the AdoMet binding mode of A. aeolicus TrmI to those of the Thermus thermophilus and Pyrococcus abyssi TrmIs, we discuss their similarities and differences. Although the binding modes to the N6 amino group of the adenine moiety of AdoMet are similar, using the side chains of acidic residues as well as hydrogen bonds, the positions of the amino acid residues involved in binding are diverse among the TrmIs from A. aeolicus, T. thermophilus, and P. abyssi. PMID:24894648

  18. A model for mis-sense error in protein synthesis: mis-charged cognate tRNA versus mis-reading of codon

    Dutta, Annwesha

    2015-01-01

    The sequence of amino acid monomers in the primary structure of protein is decided by the corresponding sequence of codons (triplets of nucleic acid monomers) on the template messenger RNA (mRNA). The polymerization of a protein, by incorporation of the successive amino acid monomers, is carried out by a molecular machine called ribosome. Transfer RNA (tRNA) molecules, each species of which is "charged" with a specific amino acid, enters the ribosome and participates in the reading of the codon by the ribosome. Both mis-reading of mRNA codon and prior mis-charging of a tRNA can lead to "mis-sense" error, i.e,. erroneous substitution of a correct amino acid monomer by an incorrect one during the synthesis of a protein. We develop a theoretical model of protein synthesis that allows for both types of contributions to the "mis-sense" error. We report exact analytical formulae for several quantities that characterize the interplay of mis-charging of tRNA and mis-reading of mRNA. The average rate of elongation of ...

  19. Crystal structure of the two-subunit tRNA m1A58 methyltransferase TRM6-TRM61 from Saccharomyces cerevisiae

    Wang, Mingxing; Zhu, Yuwei; Wang, Chongyuan; Fan, Xiaojiao; Jiang, Xuguang; Ebrahimi, Mohammad; Qiao, Zhi; Niu, Liwen; Teng, Maikun; Li, Xu

    2016-01-01

    The N1 methylation of adenine at position 58 (m1A58) of tRNA is an important post-transcriptional modification, which is vital for maintaining the stability of the initiator methionine tRNAiMet. In eukaryotes, this modification is performed by the TRM6-TRM61 holoenzyme. To understand the molecular mechanism that underlies the cooperation of TRM6 and TRM61 in the methyl transfer reaction, we determined the crystal structure of TRM6-TRM61 holoenzyme from Saccharomyces cerevisiae in the presence and absence of its methyl donor S-Adenosyl-L-methionine (SAM). In the structures, two TRM6-TRM61 heterodimers assemble as a heterotetramer. Both TRM6 and TRM61 subunits comprise an N-terminal β-barrel domain linked to a C-terminal Rossmann-fold domain. TRM61 functions as the catalytic subunit, containing a methyl donor (SAM) binding pocket. TRM6 diverges from TRM61, lacking the conserved motifs used for binding SAM. However, TRM6 cooperates with TRM61 forming an L-shaped tRNA binding regions. Collectively, our results provide a structural basis for better understanding the m1A58 modification of tRNA occurred in Saccharomyces cerevisiae. PMID:27582183

  20. Structure–function relations in the NTPase domain of the antiviral tRNA ribotoxin Escherichia coli PrrC

    Breakage of tRNA by Escherichia coli anticodon nuclease PrrC (EcoPrrC) underlies a host antiviral response to phage T4 infection. Expression of EcoPrrC is cytocidal in yeast, signifying that PrrC ribotoxicity crosses phylogenetic domain boundaries. EcoPrrC consists of an N-terminal NTPase module that resembles ABC transporters and a C-terminal nuclease module that is sui generis. PrrC homologs are prevalent in many other bacteria. Here we report that Haemophilus influenzae PrrC is toxic in E. coli and yeast. To illuminate structure–activity relations, we conducted a new round of mutational analysis of EcoPrrC guided by primary structure conservation among toxic PrrC homologs. We indentify 17 candidate active site residues in the NTPase module that are essential for toxicity in yeast when EcoPrrC is expressed at high gene dosage. Their functions could be educed by integrating mutational data with the atomic structure of the transition-state complex of a homologous ABC protein.

  1. A Gateway platform for functional genomics in Haloferax volcanii: deletion of three tRNA modification genes

    Basma El Yacoubi

    2009-01-01

    Full Text Available In part due to the existence of simple methods for its cultivation and genetic manipulation, Haloferax volcanii is a major archaeal model organism. It is the only archaeon for which the whole set of post-transcriptionally modified tRNAs has been sequenced, allowing for an in silico prediction of all RNA modification genes present in the organism. One approach to check these predictions experimentally is via the construction of targeted gene deletion mutants. Toward this goal, an integrative “Gateway vector” that allows gene deletion in H. volcanii uracil auxotrophs was constructed. The vector was used to delete three predicted tRNA modification genes: HVO_2001 (encoding an archaeal transglycosyl tranferase or arcTGT, which is involved in archeosine biosynthesis; HVO_2348 (encoding a newly discovered GTP cyclohydrolase I, which catalyzes the first step common to archaeosine and folate biosynthesis; and HVO_2736 (encoding a member of the COG1444 family, which is involved in N4-acetylcytidine (ac4C formation. Preliminary phenotypic analysis of the deletion mutants was conducted, and confirmed all three predictions.

  2. Point mutation in mitochondrial tRNA gene is associated with polycystic ovary syndrome and insulin resistance.

    Ding, Yu; Zhuo, Guangchao; Zhang, Caijuan; Leng, Jianhang

    2016-04-01

    Polycystic ovarian syndrome (PCOS) is characterized by chronic anovulation, hyperandrogenism and polycystic ovaries. To date, the molecular mechanisms underlying PCOS have remained to be fully elucidated. As recent studies have revealed a positive association between mitochondrial dysfunction and PCOS, current investigations focus on mutations in the mitochondrial genome of patients with POCS. The present study reported a Chinese patient with PCOS. Sequence analysis of the mitochondrial genome showed the presence of homoplasmic ND5 T12338C and tRNASer (UCN) C7492T mutations as well as a set of polymorphisms belonging to the human mitochondrial haplogroup F2. The T12338C mutation is known to decrease the ND5 mRNA levels and to inhibit the processing of RNA precursors. The C7492T mutation, which occurred at the highly conserved nucleotide in the anticodon stem of the tRNASer (UCN) gene, is important for the tRNA steady‑state level as well as the aminoacylation ability. Therefore, the combination of the ND5 T12338C and tRNASer (UCN) C7492T mutations may lead to mitochondrial dysfunction, and is likely to be involved in the pathogenesis of PCOS. The present study provided novel insight into the molecular mechanisms of PCOS. PMID:26935780

  3. Evolutionary Limitation and Opportunities for Developing tRNA Synthetase Inhibitors with 5-Binding-Mode Classification

    Pengfei Fang

    2015-12-01

    Full Text Available Aminoacyl-tRNA synthetases (aaRSs are enzymes that catalyze the transfer of amino acids to their cognate tRNAs as building blocks for translation. Each of the aaRS families plays a pivotal role in protein biosynthesis and is indispensable for cell growth and survival. In addition, aaRSs in higher species have evolved important non-translational functions. These translational and non-translational functions of aaRS are attractive for developing antibacterial, antifungal, and antiparasitic agents and for treating other human diseases. The interplay between amino acids, tRNA, ATP, EF-Tu and non-canonical binding partners, had shaped each family with distinct pattern of key sites for regulation, with characters varying among species across the path of evolution. These sporadic variations in the aaRSs offer great opportunity to target these essential enzymes for therapy. Up to this day, growing numbers of aaRS inhibitors have been discovered and developed. Here, we summarize the latest developments and structural studies of aaRS inhibitors, and classify them with distinct binding modes into five categories.

  4. Novel base-pairing interactions at the tRNA wobble position crucial for accurate reading of the genetic code

    Rozov, Alexey; Demeshkina, Natalia; Khusainov, Iskander; Westhof, Eric; Yusupov, Marat; Yusupova, Gulnara

    2016-01-01

    Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNALysUUU with hypermodified 5-methylaminomethyl-2-thiouridine (mnm5s2U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine-pyrimidine mismatches. We show that mnm5s2U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism.

  5. Structure-function relations in the NTPase domain of the antiviral tRNA ribotoxin Escherichia coli PrrC

    Meineke, Birthe; Shuman, Stewart, E-mail: s-shuman@ski.mskcc.org

    2012-06-05

    Breakage of tRNA by Escherichia coli anticodon nuclease PrrC (EcoPrrC) underlies a host antiviral response to phage T4 infection. Expression of EcoPrrC is cytocidal in yeast, signifying that PrrC ribotoxicity crosses phylogenetic domain boundaries. EcoPrrC consists of an N-terminal NTPase module that resembles ABC transporters and a C-terminal nuclease module that is sui generis. PrrC homologs are prevalent in many other bacteria. Here we report that Haemophilus influenzae PrrC is toxic in E. coli and yeast. To illuminate structure-activity relations, we conducted a new round of mutational analysis of EcoPrrC guided by primary structure conservation among toxic PrrC homologs. We indentify 17 candidate active site residues in the NTPase module that are essential for toxicity in yeast when EcoPrrC is expressed at high gene dosage. Their functions could be educed by integrating mutational data with the atomic structure of the transition-state complex of a homologous ABC protein.

  6. Cardiac abnormalities in diabetic patients with mutation in the mitochondrial tRNA Leu(UUR)Gene

    An A-to-G transition at position 3243 of the mitochondrial DNA is known to be a pathogenic factor for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), diabetes and cardiomyopathy. This mutation causes dysfunction of the central nervous system in MELAS. Because the heart, as well as the brain and nervous system, is highly dependent on the energy produced by mitochondrial oxidation, these tissues are more vulnerable to mitochondrial defects. Cardiac abnormalities were assessed in 10 diabetic patients associated with this mutation using echocardiography and 123I-metaiodobenzylguanidine (MIBG) scintigraphy, and compared with 19 diabetic patients without the mutation. Duration of diabetes, therapy, control of blood glucose and diabetic complications, such as diabetic retinopathy and nephropathy, were not different between the 2 groups. Diabetic patients with the mutation had a significantly thicker interventricular septum (16.8±3.7 vs 11.0±1.6 mm, p0.05). In conclusion, left ventricular hypertrophy with or without abnormal wall motion and severely reduced MIBG uptake may be characteristic in diabetic patients with a mutation in the mitochondrial tRNA Leu(UUR) gene. (author)

  7. An adequate approach to image retrieval based on local level feature extraction

    Image retrieval based on text annotation has become obsolete and is no longer interesting for scientists because of its high time complexity and low precision in results. Alternatively, increase in the amount of digital images has generated an excessive need for an accurate and efficient retrieval system. This paper proposes content based image retrieval technique at a local level incorporating all the rudimentary features. Image undergoes the segmentation process initially and each segment is then directed to the feature extraction process. The proposed technique is also based on image?s content which primarily includes texture, shape and color. Besides these three basic features, FD (Fourier Descriptors) and edge histogram descriptors are also calculated to enhance the feature extraction process by taking hold of information at the boundary. Performance of the proposed method is found to be quite adequate when compared with the results from one of the best local level CBIR (Content Based Image Retrieval) techniques. (author)

  8. Adequate bases of phase space master integrals for $gg \\to h$ at NNLO and beyond

    Höschele, Maik; Ueda, Takahiro

    2014-01-01

    We study master integrals needed to compute the Higgs boson production cross section via gluon fusion in the infinite top quark mass limit, using a canonical form of differential equations for master integrals, recently identified by Henn, which makes their solution possible in a straightforward algebraic way. We apply the known criteria to derive such a suitable basis for all the phase space master integrals in afore mentioned process at next-to-next-to-leading order in QCD and demonstrate that the method is applicable to next-to-next-to-next-to-leading order as well by solving a non-planar topology. Furthermore, we discuss in great detail how to find an adequate basis using practical examples. Special emphasis is devoted to master integrals which are coupled by their differential equations.

  9. Providing for decommissioning funds: minimum conditions for adequate funding and comparative analysis

    The present contribution analyses the minimum criteria that need to be applied for adequate financial arrangements for decommissioning, as well as the possible financing mechanisms and the recommended investment policy for decommissioning funds. Furthermore, practical examples of decommissioning mechanisms in the United States of America, France, the United Kingdom, Germany, Sweden, Spain and Belgium will be studied. A question frequently asked about nuclear energy is how to deal with its impact on the environment. The issue of decommissioning of nuclear power plants, and in particular the funding of such decommissioning, is part of this discussion. The IAEA fundamental safety principles and safety requirements already make clear that radioactive waste must be managed in such a way as to avoid imposing an undue burden on future generations. The government shall make provision for the safe decommissioning of facilities, the safe management and disposal of radioactive waste arising from facilities and activities, and the safe management of spent fuel. (author)

  10. An Adequate Approach to Image Retrieval Based on Local Level Feature Extraction

    Sumaira Muhammad Hayat Khan

    2010-10-01

    Full Text Available Image retrieval based on text annotation has become obsolete and is no longer interesting for scientists because of its high time complexity and low precision in results. Alternatively, increase in the amount of digital images has generated an excessive need for an accurate and efficient retrieval system. This paper proposes content based image retrieval technique at a local level incorporating all the rudimentary features. Image undergoes the segmentation process initially and each segment is then directed to the feature extraction process. The proposed technique is also based on image?s content which primarily includes texture, shape and color. Besides these three basic features, FD (Fourier Descriptors and edge histogram descriptors are also calculated to enhance the feature extraction process by taking hold of information at the boundary. Performance of the proposed method is found to be quite adequate when compared with the results from one of the best local level CBIR (Content Based Image Retrieval techniques.

  11. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt.

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8-10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100-199 μg/L). The median Tg concentration was 8.7 μg/L, which was intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  12. 40 CFR 141.522 - How does the State determine whether my system's watershed control requirements are adequate?

    2010-07-01

    ... my system's watershed control requirements are adequate? 141.522 Section 141.522 Protection of... Additional Watershed Control Requirements for Unfiltered Systems § 141.522 How does the State determine whether my system's watershed control requirements are adequate? During an onsite inspection...

  13. Adequate sleep among adolescents is positively associated with health status and health-related behaviors

    Jeng Yi-Jong

    2006-03-01

    Full Text Available Abstract Background Amount of sleep is an important indicator of health and well-being in children and adolescents. Adequate sleep (AS: adequate sleep is defined as 6–8 hours per night regularly is a critical factor in adolescent health and health-related behaviors. The present study was based on a health promotion project previously conducted on adolescents in Tao-Yuan County, Taiwan. The aim was to examine the relationship between AS during schooldays and excessive body weight, frequency of visiting doctors and health-related behaviors among Taiwanese adolescents. Methods A cross-sectional study design, categorical and multivariate data analyses were used. The hypotheses investigated were: high frequency of AS is positively associated with lack of obesity and less frequent visits to doctors; and high frequency AS is positively associated with health-related behavior. Results A total of 656 boys (53.2% and girls (46.8%, ranging in age from 13–18 years were studied between January and June 2004. Three hundred and fifty seven subjects (54% reported that they slept less than the suggested 6–8 hours on schooldays. A significant negative association was found between low sleep and of the following health-related behaviors: (1 life appreciation; (2 taking responsibility for health; (3 adopting healthy diet; (4 effective stress management; (5 regular exercise; and (6 total AHP score. High frequency AS was associated with low frequencies of obesity after potential confounding factors were controlled. Junior high school adolescents reported significantly higher frequencies of AS than high school participants. Gender, family structure, home location and frequency of television watching or computer use were not significantly associated with AS. Conclusion These findings support the proposition that AS is associated with good health status and high-frequency adoption of health-related behavior. Furthermore, these findings suggest that inadequate

  14. Dose reduction and adequate image quality in digital radiography: a contradiction?

    Dose reduction and adequate image quality in digital radiography - a contradiction ?Digital radiography has already replaced traditional screen-film systems. Substantial improvements in both dose efficiency and spatial resolution demonstrate the rapid developments in digital radiography. Needle-detector systems have shown up to a 50% dose reduction compared to traditional screen-film systems. There is also a dose reduction capability of up to 50% comparing direct radiography (DR) systems to computed radiography (CR) systems for chest X-rays. However, despite the most recent achievements of CR technology, the dose efficiency of DR systems (caesium iodide flat-panel detector) is unparalleled. The progress in detector technology has contributed to dose reduction and improved image quality, while saving time and providing a higher examination rate. The use of dose indicators and longitudinal dose control are important to avoid substantial accidental dose increase. The dose applied to patients should fall markedly below the defined diagnostic reference levels within the European Union. Regular quality control, as well as continuous education and training of medical and technical personnel, contribute to ensure that the ALARA (as low as reasonably achievable) principle is consistently followed. (orig.)

  15. Improved ASTM G72 Test Method for Ensuring Adequate Fuel-to-Oxidizer Ratios

    Juarez, Alfredo; Harper, Susana Tapia

    2016-01-01

    The ASTM G72/G72M-15 Standard Test Method for Autogenous Ignition Temperature of Liquids and Solids in a High-Pressure Oxygen-Enriched Environment is currently used to evaluate materials for the ignition susceptibility driven by exposure to external heat in an enriched oxygen environment. Testing performed on highly volatile liquids such as cleaning solvents has proven problematic due to inconsistent test results (non-ignitions). Non-ignition results can be misinterpreted as favorable oxygen compatibility, although they are more likely associated with inadequate fuel-to-oxidizer ratios. Forced evaporation during purging and inadequate sample size were identified as two potential causes for inadequate available sample material during testing. In an effort to maintain adequate fuel-to-oxidizer ratios within the reaction vessel during test, several parameters were considered, including sample size, pretest sample chilling, pretest purging, and test pressure. Tests on a variety of solvents exhibiting a range of volatilities are presented in this paper. A proposed improvement to the standard test protocol as a result of this evaluation is also presented. Execution of the final proposed improved test protocol outlines an incremental step method of determining optimal conditions using increased sample sizes while considering test system safety limits. The proposed improved test method increases confidence in results obtained by utilizing the ASTM G72 autogenous ignition temperature test method and can aid in the oxygen compatibility assessment of highly volatile liquids and other conditions that may lead to false non-ignition results.

  16. The rat adequately reflects human responses to exercise in blood biochemical profile: a comparative study.

    Goutianos, Georgios; Tzioura, Aikaterini; Kyparos, Antonios; Paschalis, Vassilis; Margaritelis, Nikos V; Veskoukis, Aristidis S; Zafeiridis, Andreas; Dipla, Konstantina; Nikolaidis, Michalis G; Vrabas, Ioannis S

    2015-02-01

    Animal models are widely used in biology and the findings of animal research are traditionally projected to humans. However, recent publications have raised concerns with regard to what extent animals and humans respond similar to physiological stimuli. Original data on direct in vivo comparison between animals and humans are scarce and no study has addressed this issue after exercise. We aimed to compare side by side in the same experimental setup rat and human responses to an acute exercise bout of matched intensity and duration. Rats and humans ran on a treadmill at 86% of maximal velocity until exhaustion. Pre and post exercise we measured 30 blood chemistry parameters, which evaluate iron status, lipid profile, glucose regulation, protein metabolism, liver, and renal function. ANOVA indicated that almost all biochemical parameters followed a similar alteration pattern post exercise in rats and humans. In fact, there were only 2/30 significant species × exercise interactions (in testosterone and globulins), indicating different responses to exercise between rats and humans. On the contrary, the main effect of exercise was significant in 15/30 parameters and marginally nonsignificant in other two parameters (copper, P = 0.060 and apolipoprotein B, P = 0.058). Our major finding is that the rat adequately mimics human responses to exercise in those basic blood biochemical parameters reported here. The physiological resemblance of rat and human blood responses after exercise to exhaustion on a treadmill indicates that the use of blood chemistry in rats for exercise physiology research is justified. PMID:25677548

  17. A test of the cerebellar hypothesis of dyslexia in adequate and inadequate responders to reading intervention.

    Barth, Amy E; Denton, Carolyn A; Stuebing, Karla K; Fletcher, Jack M; Cirino, Paul T; Francis, David J; Vaughn, Sharon

    2010-05-01

    The cerebellar hypothesis of dyslexia posits that cerebellar deficits are associated with reading disabilities and may explain why some individuals with reading disabilities fail to respond to reading interventions. We tested these hypotheses in a sample of children who participated in a grade 1 reading intervention study (n = 174) and a group of typically achieving children (n = 62). At posttest, children were classified as adequately responding to the intervention (n = 82), inadequately responding with decoding and fluency deficits (n = 36), or inadequately responding with only fluency deficits (n = 56). Based on the Bead Threading and Postural Stability subtests from the Dyslexia Screening Test-Junior, we found little evidence that assessments of cerebellar functions were associated with academic performance or responder status. In addition, we did not find evidence supporting the hypothesis that cerebellar deficits are more prominent for poor readers with "specific" reading disabilities (i.e., with discrepancies relative to IQ) than for poor readers with reading scores consistent with IQ. In contrast, measures of phonological awareness, rapid naming, and vocabulary were strongly associated with responder status and academic outcomes. These results add to accumulating evidence that fails to associate cerebellar functions with reading difficulties. PMID:20298639

  18. Are GPs adequately equipped with the knowledge for educating and counseling of families with ADHD children?

    Zarei Nabi

    2010-01-01

    Full Text Available Abstract Background Attention deficit hyperactivity disorder is one of the most common child psychiatry disorders. General physicians (GP, as primary care providers, can have an important role in screening and treatment of ADHD. This study aimed to survey GPs' knowledge, attitude, and their views of their role in the screening, diagnosing and managing children with ADHD. Methods Six hundred and sixty five general physicians in Shiraz, Iran, answered a self-reported questionnaire on ADHD. The questionnaire consisted of questions regarding socio-demographic characteristics such as age, the duration of practice as a GP, marital status, general knowledge about ADHD, and the management of ADHD. Results Less than half of them believed that they have adequate knowledge and information about this disorder. They usually do not like to be the primary care providers for children with ADHD. The majority of them prefer to refer the children to related specialists, mostly psychiatrists or psychologists. More than one third of them believed that sugar is a cause of ADHD. Only 6.6% of them reported that ADHD persists for the whole life. Their knowledge about methylphenidate is reasonable. Conclusions As many other countries worldwide, the knowledge of GPs about ADHD should be improved. They do not asses and manage children with probable ADHD by themselves without referring to related professionals. They do not opt for the use of methylphenidate.

  19. Determination of the need for selenium by chicks fed practical diets adequate in vitamin E

    Combs, G.F. Jr.; Su, Q.; Liu, C.H.; Sinisalo, M.; Combs, S.B.

    1986-03-01

    Experiments were conducted to compare the dietary needs for selenium (Se) by chicks fed either purified (amino acid-based) or practical (corn- and soy-based) diets that were adequate with respect to vitamin E (i.e., contained 100 IU/kg) and all other known nutrients with the single exception of Se (i.e., contained only 0.10 ppm Se). Studies were conducted in Ithaca using Single Comb White Leghorn chicks fed the purified basal diet and in Beijing using chicks of the same breed fed either the same purified basal diet or the practical diet formulated to be similar to that used in poultry production in some parts of China and the US. Results showed that each basal diet produced severe depletion of Se-dependent glutathione peroxidase (SeGSHpx) in plasma, liver and pancreas according to the same time-course, but that other consequences of severe uncomplicated Se deficiency were much more severe among chicks fed the purified diet (e.g., growth depression, pancreatic dysfunction as indicated by elevated plasma amylase and abnormal pancreatic histology). Chicks fed the practical Se-deficient diet showed reduced pancreas levels of copper, zinc and molybdenum and elevated plasma levels of iron; they required ca. 0.10 ppm dietary Se to sustain normal SeGSHpx in several tissues and to prevent elevated amylase in plasma. The dietary Se requirement of the chick is, therefore, estimated to be 0.10 ppm.

  20. Cardiac abnormalities in diabetic patients with mutation in the mitochondrial tRNA {sup Leu(UUR)}Gene

    Ueno, Hiroshi [Hyogo Medical Center for Adults, Akashi (Japan); Shiotani, Hideyuki

    1999-11-01

    An A-to-G transition at position 3243 of the mitochondrial DNA is known to be a pathogenic factor for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), diabetes and cardiomyopathy. This mutation causes dysfunction of the central nervous system in MELAS. Because the heart, as well as the brain and nervous system, is highly dependent on the energy produced by mitochondrial oxidation, these tissues are more vulnerable to mitochondrial defects. Cardiac abnormalities were assessed in 10 diabetic patients associated with this mutation using echocardiography and {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy, and compared with 19 diabetic patients without the mutation. Duration of diabetes, therapy, control of blood glucose and diabetic complications, such as diabetic retinopathy and nephropathy, were not different between the 2 groups. Diabetic patients with the mutation had a significantly thicker interventricular septum (16.8{+-}3.7 vs 11.0{+-}1.6 mm, p<0.001) than those without the mutation. Fractional shortening was lower in diabetic patients with the mutation than those without it (30.7{+-}7.0 vs 42.5{+-}6.6, p<0.001). MIBG uptake on the delayed MIBG image was significantly lower in diabetic patients with the mutation than in those without the mutation (mean value of the heart to mediastinum ratio: 1.6{+-}0.2 vs 2.0{+-}0.4, p>0.05). In conclusion, left ventricular hypertrophy with or without abnormal wall motion and severely reduced MIBG uptake may be characteristic in diabetic patients with a mutation in the mitochondrial tRNA {sup Leu(UUR)} gene. (author)

  1. Yeast mitochondrial threonyl-tRNA synthetase recognizes tRNA isoacceptors by distinct mechanisms and promotes CUN codon reassignment

    Ling, Jiqiang; Peterson, Kaitlyn M.; Simonovic, Ivana; Cho, Chris; Soll, Dieter; Simonovic, Miljan (Yale); (UIC)

    2014-03-12

    Aminoacyl-tRNA synthetases (aaRSs) ensure faithful translation of mRNA into protein by coupling an amino acid to a set of tRNAs with conserved anticodon sequences. Here, we show that in mitochondria of Saccharomyces cerevisiae, a single aaRS (MST1) recognizes and aminoacylates two natural tRNAs that contain anticodon loops of different size and sequence. Besides a regular ?? with a threonine (Thr) anticodon, MST1 also recognizes an unusual ??, which contains an enlarged anticodon loop and an anticodon triplet that reassigns the CUN codons from leucine to threonine. Our data show that MST1 recognizes the anticodon loop in both tRNAs, but employs distinct recognition mechanisms. The size but not the sequence of the anticodon loop is critical for ?? recognition, whereas the anticodon sequence is essential for aminoacylation of ??. The crystal structure of MST1 reveals that, while lacking the N-terminal editing domain, the enzyme closely resembles the bacterial threonyl-tRNA synthetase (ThrRS). A detailed structural comparison with Escherichia coli ThrRS, which is unable to aminoacylate ??, reveals differences in the anticodon-binding domain that probably allow recognition of the distinct anticodon loops. Finally, our mutational and modeling analyses identify the structural elements in MST1 (e.g., helix {alpha}11) that define tRNA selectivity. Thus, MTS1 exemplifies that a single aaRS can recognize completely divergent anticodon loops of natural isoacceptor tRNAs and that in doing so it facilitates the reassignment of the genetic code in yeast mitochondria.

  2. Post-transcriptional Boolean computation by combining aptazymes controlling mRNA translation initiation and tRNA activation.

    Klauser, Benedikt; Saragliadis, Athanasios; Ausländer, Simon; Wieland, Markus; Berthold, Michael R; Hartig, Jörg S

    2012-09-01

    In cellular systems environmental and metabolic signals are integrated for the conditional control of gene expression. On the other hand, artificial manipulation of gene expression is of high interest for metabolic and genetic engineering. Especially the reprogramming of gene expression patterns to orchestrate cellular responses in a predictable fashion is considered to be of great importance. Here we introduce a highly modular RNA-based system for performing Boolean logic computation at a post-transcriptional level in Escherichia coli. We have previously shown that artificial riboswitches can be constructed by utilizing ligand-dependent Hammerhead ribozymes (aptazymes). Employing RNA self-cleavage as the expression platform-mechanism of an artificial riboswitch has the advantage that it can be applied to control several classes of RNAs such as mRNAs, tRNAs, and rRNAs. Due to the highly modular and orthogonal nature of these switches it is possible to combine aptazyme regulation of activating a suppressor tRNA with the regulation of mRNA translation initiation. The different RNA classes can be controlled individually by using distinct aptamers for individual RNA switches. Boolean logic devices are assembled by combining such switches in order to act on the expression of a single mRNA. In order to demonstrate the high modularity, a series of two-input Boolean logic operators were constructed. For this purpose, we expanded our aptazyme toolbox with switches comprising novel behaviours with respect to the small molecule triggers thiamine pyrophosphate (TPP) and theophylline. Then, individual switches were combined to yield AND, NOR, and ANDNOT gates. This study demonstrates that post-transcriptional aptazyme-based switches represent versatile tools for engineering advanced genetic devices and circuits without the need for regulatory protein cofactors. PMID:22777205

  3. The transfer RNA genes in Oryza sativa L.ssp.indica

    王希胤; 史晓黎; 郝柏林

    2002-01-01

    The availability of the draft genome sequence of Oryza sativa L. ssp. indica has made it possible to study the rice tRNA genes. A total of 596 tRNA genes, including 3 selenocysteine tRNA genes and one suppressor tRNA gene are identified in 127551 rice contigs. There are 45 species of tRNA genes and the revised wobble hypothesis proposed by Guthrie and Abelson is perfectly obeyed. The relationship between codon usage and the number of corresponding tRNA genes is discussed. Redundancy may exist in the present list of tRNA genes and novel ones may be found in the future. A set of 33 tRNA genes is discovered in the complete chloroplast genome of Oryza sativa L. ssp. indica. These tRNA genes are identical to those in ssp. japonica identified by us independently from the origional annotation.

  4. The Pai-associated leuX specific tRNA5(Leu) affects type 1fimbriation in pathogenic Escherichia coli by control of FimB recombinase expression

    Ritter, A.; Gally, D.; Olsen, Peter Bjarke; Friedrich, A.; Dobrindt, U; Klemm, Per; Hacker, J.

    1997-01-01

    The uropathogenic Escherichia coli strain 536 (06:K15:H31) carries two large chromosomalpathogenicity islands (Pais). Both Pais are flanked by tRNA genes. Spontaneous deletion of Pai IIresults in truncation of the leuX tRNA5Leu gene. This tRNA is required for the expression of type 1fimbriae (Fim...... recognized by tRNA5Leu, fimE contains only two. It was proposed thatturning on the fim switch requires efficient translation of FimB, in turn requiring tRNA5Leu. Strainsin which the TTG codons in fimB were replaced with CTG codons at the wild-type locus were ableto produce type 1 fimbriae in the absence of...... to be switched off inleuX-derivatives of E. coli 536, but could be found in the on position when the codon-altered fimBgene was exchanged into the chromosome of these strains. From these data, it is apparent thattRNA5Leu is required for efficient translation of FimB, in turn, leading to type 1...

  5. Determinants of prompt and adequate care among presumed malaria cases in a community in eastern Rwanda: A cross sectional study

    Ingabire, C.M.; Kateera, F.; Hakizimana, E.; Rulisa, A.; Muvunyi, C.; Mens, P.; Koenraadt, C.J.M.; Mutesa, L.; Vugt, M. van; Borne, B. van den; Alaii, J.

    2016-01-01

    Background: In order to understand factors influencing fever/malaria management practices among community-based individuals, the study evaluated psychosocial, socio-demographic and environmental determinants of prompt and adequate healthcare-seeking behaviours. Methods: A quantitative household (HH)

  6. Prevention of mother to child transmission lay counsellors: Are they adequately trained?

    Catherine H. Thurling

    2012-05-01

    Full Text Available South Africa’s high prevalence of human immunodeficiency virus (HIV infected women requires a comprehensive health care approach to pregnancy because of the added risk of their HIV status. As a result of the shortage of health care workers in South Africa, lay counsellors play important roles in the prevention of mother to child transmission of HIV (PMTCT.There is no standardization of training of lay counsellors in South Africa, and training varies in length depending on the training organisation.The study aimed to investigate the training of lay counsellors by analysing their training curricula and interviewing lay counsellors about their perceptions of their training.A two phase research method was applied. Phase one documented an analysis of the training curricula. Phase two was semi-structured interviews with the participants. Purposive sampling was undertaken for this study. The total sample size was 13 people, with a final sample of 9 participants, determined at the point of data saturation.The research was qualitative, descriptive and contextual in design. The curricula analysed had different styles of delivery, and the approaches to learning and courses varied, resulting in inconsistent training outcomes. A need for supervision and mentorship in the working environment was also noted.The training of lay counsellors needs to be adapted to meet the extended roles that they are playing in PMTCT. The standardization of training programmes, and the incorporation of a system of mentorship in the work environment, would ensure that the lay counsellors are adequately prepared for their role in PMTCT.

  7. Prioritising pharmaceuticals for environmental risk assessment: Towards adequate and feasible first-tier selection.

    Roos, V; Gunnarsson, L; Fick, J; Larsson, D G J; Rudén, C

    2012-04-01

    The presence of pharmaceuticals in the aquatic environment, and the concerns for negative effects on aquatic organisms, has gained increasing attention over the last years. As ecotoxicity data are lacking for most active pharmaceutical ingredients (APIs), it is important to identify strategies to prioritise APIs for ecotoxicity testing and environmental monitoring. We have used nine previously proposed prioritisation schemes, both risk- and hazard-based, to rank 582 APIs. The similarities and differences in overall ranking results and input data were compared. Moreover, we analysed how well the methods ranked seven relatively well-studied APIs. It is concluded that the hazard-based methods were more successful in correctly ranking the well-studied APIs, but the fish plasma model, which includes human pharmacological data, also showed a high success rate. The results of the analyses show that the input data availability vary significantly; some data, such as logP, are available for most API while information about environmental concentrations and bioconcentration are still scarce. The results also suggest that the exposure estimates in risk-based methods need to be improved and that the inclusion of effect measures at first-tier prioritisation might underestimate risks. It is proposed that in order to develop an adequate prioritisation scheme, improved data on exposure such as degradation and sewage treatment removal and bioconcentration ability should be further considered. The use of ATC codes may also be useful for the development of a prioritisation scheme that includes the mode of action of pharmaceuticals and, to some extent, mixture effects. PMID:22361586

  8. Ensuring Adequate Health and Safety Information for Decision Makers during Large-Scale Chemical Releases

    Petropoulos, Z.; Clavin, C.; Zuckerman, B.

    2015-12-01

    The 2014 4-Methylcyclohexanemethanol (MCHM) spill in the Elk River of West Virginia highlighted existing gaps in emergency planning for, and response to, large-scale chemical releases in the United States. The Emergency Planning and Community Right-to-Know Act requires that facilities with hazardous substances provide Material Safety Data Sheets (MSDSs), which contain health and safety information on the hazardous substances. The MSDS produced by Eastman Chemical Company, the manufacturer of MCHM, listed "no data available" for various human toxicity subcategories, such as reproductive toxicity and carcinogenicity. As a result of incomplete toxicity data, the public and media received conflicting messages on the safety of the contaminated water from government officials, industry, and the public health community. Two days after the governor lifted the ban on water use, the health department partially retracted the ban by warning pregnant women to continue avoiding the contaminated water, which the Centers for Disease Control and Prevention deemed safe three weeks later. The response in West Virginia represents a failure in risk communication and calls to question if government officials have sufficient information to support evidence-based decisions during future incidents. Research capabilities, like the National Science Foundation RAPID funding, can provide a solution to some of the data gaps, such as information on environmental fate in the case of the MCHM spill. In order to inform policy discussions on this issue, a methodology for assessing the outcomes of RAPID and similar National Institutes of Health grants in the context of emergency response is employed to examine the efficacy of research-based capabilities in enhancing public health decision making capacity. The results of this assessment highlight potential roles rapid scientific research can fill in ensuring adequate health and safety data is readily available for decision makers during large

  9. Do Foley catheters adequately drain the bladder? Evidence from CT imaging studies

    Introduction: The Foley catheter has been widely assumed to be an effective means of draining the bladder. However, recent studies have brought into question its efficacy. The objective of our study is to further assess the adequacy of Foley catheter for complete drainage of the bladder. Materials and Methods: Consecutive catheterized patients were identified from a retrospective review of contrast enhanced and non-contrast enhanced computed tomographic (CT) abdomen and pelvis studies completed from 7/1/2011-6/30/2012. Residual urine volume (RUV) was measured using 5mm axial CT sections as follows: The length (L) and width (W) of the bladder in the section with the greatest cross sectional area was combined with bladder height (H) as determined by multiplanar reformatted images in order to calculate RUV by applying the formula for the volume (V) of a sphere in a cube:V=(π/6)⁎L⁎W⁎H). Results: RUVs of 167 (mean age 67) consecutively catheterized men (n=72) and women (n=95) identified by CT abdomen and pelvis studies were calculated. The mean RUV was 13.2 mL (range: 0.0 mL-859.1 mL, standard deviation: 75.9 mL, margin of error at 95% confidence:11.6 mL). Four (2.4%) catheterized patients had RUVs of >50 mL, two of whom had an improperly placed catheter tip noted on their CT-reports. Conclusions: Previous studies have shown that up to 43% of catheterized patients had a RUV greater than 50 mL, suggesting inadequacy of bladder drainage via the Foley catheter. Our study indicated that the vast majority of patients with Foley catheters (97.6%), had adequately drained bladders with volumes of <50 mL. (author)

  10. Do Foley catheters adequately drain the bladder? Evidence from CT imaging studies

    Avulova, Svetlana; Li, Valery J.; Khusid, Johnathan A. [Department of Urology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Choi, Woo S. [Radiology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Weiss, Jeffrey P., E-mail: johnathan.khusid@downstate.edu [Department of Urology, Weill Cornell Medical College, New York, NY (United States)

    2015-05-15

    Introduction: The Foley catheter has been widely assumed to be an effective means of draining the bladder. However, recent studies have brought into question its efficacy. The objective of our study is to further assess the adequacy of Foley catheter for complete drainage of the bladder. Materials and Methods: Consecutive catheterized patients were identified from a retrospective review of contrast enhanced and non-contrast enhanced computed tomographic (CT) abdomen and pelvis studies completed from 7/1/2011-6/30/2012. Residual urine volume (RUV) was measured using 5mm axial CT sections as follows: The length (L) and width (W) of the bladder in the section with the greatest cross sectional area was combined with bladder height (H) as determined by multiplanar reformatted images in order to calculate RUV by applying the formula for the volume (V) of a sphere in a cube:V=(π/6)⁎L⁎W⁎H). Results: RUVs of 167 (mean age 67) consecutively catheterized men (n=72) and women (n=95) identified by CT abdomen and pelvis studies were calculated. The mean RUV was 13.2 mL (range: 0.0 mL-859.1 mL, standard deviation: 75.9 mL, margin of error at 95% confidence:11.6 mL). Four (2.4%) catheterized patients had RUVs of >50 mL, two of whom had an improperly placed catheter tip noted on their CT-reports. Conclusions: Previous studies have shown that up to 43% of catheterized patients had a RUV greater than 50 mL, suggesting inadequacy of bladder drainage via the Foley catheter. Our study indicated that the vast majority of patients with Foley catheters (97.6%), had adequately drained bladders with volumes of <50 mL. (author)

  11. Emotional Experiences of Obese Women with Adequate Gestational Weight Variation: A Qualitative Study.

    Débora Bicudo Faria-Schützer

    Full Text Available As a result of the growth of the obese population, the number of obese women of fertile age has increased in the last few years. Obesity in pregnancy is related to greater levels of anxiety, depression and physical harm. However, pregnancy is an opportune moment for the intervention of health care professionals to address obesity. The objective of this study was to describe how obese pregnant women emotionally experience success in adequate weight control.Using a qualitative design that seeks to understand content in the field of health, the sample of subjects was deliberated, with thirteen obese pregnant women selected to participate in an individual interview. Data was analysed by inductive content analysis and includes complete transcription of the interviews, re-readings using suspended attention, categorization in discussion topics and the qualitative and inductive analysis of the content. The analysis revealed four categories, three of which show the trajectory of body care that obese women experience during pregnancy: 1 The obese pregnant woman starts to think about her body;2 The challenge of the diet for the obese pregnant woman; 3 The relation of the obese pregnant woman with the team of antenatal professionals. The fourth category reveals the origin of the motivation for the change: 4 The potentializing factors for change: the motivation of the obese woman while pregnant.During pregnancy, obese women are more in touch with themselves and with their emotional conflicts. Through the transformations of their bodies, women can start a more refined self-care process and experience of the body-mind unit. The fear for their own and their baby's life, due to the risks posed by obesity, appears to be a great potentializing factor for change. The relationship with the professionals of the health care team plays an important role in the motivational support of the obese pregnant woman.

  12. Development of adequate meteorological monitoring standards for safety analysis of nuclear facilities

    The aim of this report is to identify what constitutes adequate meteorological information for airborne dispersion calculations in case of releases from nuclear facilities during 'normal operation', 'design postulated accidents', and 'emergency situations'. The models used for estimating downwind dispersion are reviewed, including short-range simple terrain, short-range complex terrain and medium to long range models with emphasis on Lagrangian models. The meteorogolical input parameters required for running these models are identified. The methods by which these parameters may be obtained from raw meteorological data are then considered. Emphasis is placed on well-tried and recommended methods rather than those which are currently being developed and lack long-term field tests. The meteorological data required to calculate the parameters that are in turn input to dispersion calculation methods can be obtained mainly from tower measurements. Recommended tower height is 50 m, with two levels of instruments (10 and 50 m) for wind speed, wind direction and temperature. Data for precipitation and solar radiation, that may be required under certain conditions and for special calculations, may be estimated from nearby representative weather stations (if available). For simple terrain, a single tower is sufficient. For complex terrain, such as coastal regions, two towers are desirable for accurate characterization of the turbulence regime in the vicinity of a release site. The report provides the necessary accuracy specifications for instruments required for the meteorological measurements. Data monitoring and recording, maintenance, quality control and assurance are also discussed. Error propagation analyses are recommended to determine the full implications of instrument accuracies on the accuracy of dispersion model predictions. 82 refs

  13. Is the standardized helmet technique adequate for irradiation of the brain and the cranial meninges?

    Purpose: To evaluate whether the standardized helmet technique is adequate to reliably cover the clinical target volume (whole brain including cranial meninges) during treatment planning and treatment delivery. Methods and Materials: In 21 patients undergoing irradiation of the brain in acute lymphoblastic leukemia or primary cerebral lymphoma, the coverage of the clinical target volume was checked with a repeat computed tomography (CT) in the treatment position (head fixation with face mask). The accuracy of field alignment was quantitatively assessed with sequential verification films. For each patient, linear and rotational discrepancies were measured between the simulation and first check film, and between five consecutive verification films. Results: Coverage of clinical target volume. In 11 cases (52%), the CT examinations showed that parts of the subfrontal region and midcranial fossa were not included by the field assigned under simulation. Accuracy of field alignment. For the total group of patients, all deviations were normally distributed with mean values between -1.2 mm and 1.5 mm and standard deviations of 2.9 mm to 3.7 mm for linear discrepancies, and 0.3 degrees ± 3.2 degrees for rotational discrepancies. For all patients, deviations were similar for the transition from simulation to the treatment machine and for subsequent treatment delivery, with 50% and 95% of absolute differences being less than 2.0 mm and 6.5 mm, respectively. Maximum linear deviations were less than 9.5 mm. Conclusions: The currently used helmet technique is inadequate to cover the clinical target volume. Repeat CT examinations are a useful method to delineate the clinical target volume on an individual patient basis. In addition, statistical fluctuations of field displacements up to 1.0 cm have to be considered when prescribing safety margins for reliable coverage of the clinical target volume during treatment planning and delivery

  14. Offering Adequate Pedagogical Progression via Mobile Equipments-Experiment of a French Engineering School

    Jean-Luc Koning

    2006-01-01

    Students may enter our 5-year engineering school in France at two levels: first and third year.However, due to their quite different backgrounds (this is especially true for third year students), we need to provide newcomers with a 6-week training period during which they follow classes in the fields where they particularly feel weak. Unfortunately, depending on the student' s background, this is not always possible to bring him/her to the expected level. Another aspect one needs to mention is that these students may not have the same weaknesses in a given field. However, for economical reasons, those classes follow a uniform program as it is not feasible to provide a customized progression. In this paper we discuss how to redesign a mathematics course so as to offer tailored exercise sequencing.Groups of 20 students could then draw their exercises from an intranet database according to their previously completed work, try to solve it by themselves, request additional hints and even ask for some direct help from the teacher. Such a database is currently under development. If it turns out several students stumble against the same difficulty the teacher could show the whole class room how to solve it using the digital projector.This project goes one step further than our initial mobile education project ( 2003 ~ 2004 ). Until recently,we had used the equipment in a unique direction, from the instructor toward the students. Here, in this new project we are focusing on the whole loop in order to offer a more adequate (personalized) pedagogical progression: from the student to the teacher (when the tablet PCs are monitored by the teacher) , and back to-ward the students (when a direct help is proded by the teacher)

  15. Access to Adequate Outpatient Depression Care for Mothers in the US: A Nationally Representative Population-Based Study

    Witt, Whitney P.; Keller, Abiola; Gottlieb, Carissa; Litzelman, Kristin; Hampton, John; Maguire, Jonathan; Hagen, Erika W.

    2009-01-01

    Maternal depression is often untreated, resulting in serious consequences for mothers and their children. Factors associated with receipt of adequate treatment for depression were examined in a population-based sample of 2,130 mothers in the USA with depression using data from the 1996-2005 Medical Expenditure Panel Survey. Chi-squared analyses were used to evaluate differences in sociodemographic and health characteristics by maternal depression treatment status (none, some, adequate). Multi...

  16. The mitochondrial genome of the stingless bee Melipona bicolor (Hymenoptera, Apidae, Meliponini: sequence, gene organization and a unique tRNA translocation event conserved across the tribe Meliponini

    Daniela Silvestre

    2008-01-01

    Full Text Available At present a complete mtDNA sequence has been reported for only two hymenopterans, the Old World honey bee, Apis mellifera and the sawfly Perga condei. Among the bee group, the tribe Meliponini (stingless bees has some distinction due to its Pantropical distribution, great number of species and large importance as main pollinators in several ecosystems, including the Brazilian rain forest. However few molecular studies have been conducted on this group of bees and few sequence data from mitochondrial genomes have been described. In this project, we PCR amplified and sequenced 78% of the mitochondrial genome of the stingless bee Melipona bicolor (Apidae, Meliponini. The sequenced region contains all of the 13 mitochondrial protein-coding genes, 18 of 22 tRNA genes, and both rRNA genes (one of them was partially sequenced. We also report the genome organization (gene content and order, gene translation, genetic code, and other molecular features, such as base frequencies, codon usage, gene initiation and termination. We compare these characteristics of M. bicolor to those of the mitochondrial genome of A. mellifera and other insects. A highly biased A+T content is a typical characteristic of the A. mellifera mitochondrial genome and it was even more extreme in that of M. bicolor. Length and compositional differences between M. bicolor and A. mellifera genes were detected and the gene order was compared. Eleven tRNA gene translocations were observed between these two species. This latter finding was surprising, considering the taxonomic proximity of these two bee tribes. The tRNA Lys gene translocation was investigated within Meliponini and showed high conservation across the Pantropical range of the tribe.

  17. MD simulation studies to investigate iso-energetic conformational behaviour of modified nucleosides m2G and m22G present in tRNA

    Rohit S Bavi

    2013-02-01

    Full Text Available Modified nucleic acid bases are most commonly found in tRNA. These may contain modifications from simple methylation to addition of bulky groups. Methylation of the four canonical nucleotide bases at a wide variety of positions is particularly prominent among the known modification. Methylation of N2 group of guanine is a relatively common modification in tRNA and rRNA. N2-methylguanosine (m2G is the second most often encountered nucleoside in E. coli tRNAs. N2, N2-dimethylguanosine (m22G is found in the majority of eukaryotic tRNAs and involved in forming base pair interactions with adjacent bases. Hence, in order to understand the structural significance of these methylated nucleic acid bases we have carried out molecular dynamics simulation to see the salvation effect. The results obtained shows iso-energetic conformational behaviors for m2G and m22G. The simulation trajectory of m2G shows regular periodical fluctuations suggesting that m2G is equally stable as either s-cis or s-trans rotamers. The two rotamers of m2G may interact canonically or non-canonically with opposite base as s-trans m2G26:C/A/U44 and s-cis m2G26:A/U44. The free rotations around the C-N bond could be the possible reason for these iso-energetic conformations. Dimethylation of G has almost no influence on base pairing with either A or U. Thus, these results reveal that modified nucleosides m2G and m22G may play an important role to prevent tRNA from adopting the unusual mitochondrial like conformation.

  18. Covalent coupling of 4-thiouridine in the initiator methionine tRNA to specific lysine residues in Escherichia coli methionyl-tRNA synthetase

    A new method has been developed to couple a lysine-reactive cross-linker to the 4-thiouridine residue at position 8 in the primary structure of the Escherichia coli initiator methionine tRNA (tRNA/sup fMet/). Incubation of the affinity-labeling tRNA/sup fMet/ derivative with E. coli methionyl-tRNA synthetase (MetRS) yielded a covalent complex of the protein and nucleic acid and resulted in loss of amino acid acceptor activity of the enzyme. A stoichiometric relationship (1:1) was observed between the amount of cross-linked tRNA and the amount of enzyme inactivated. Cross-linking was effectively inhibited by unmodified tRNA/sup fMet/, but not by noncognate tRNA/sup Phe/. The covalent complex was digested with trypsin, and the resulting tRNA-bound peptides were purified from excess free peptides by anion-exchange chromatography. The tRNA was then degraded with T1 ribonuclease, and the peptides bound to the 4-thiouridine-containing dinucleotide were purified by high-pressure liquid chromatography. Two major peptide products were isolated plus several minor peptides. N-Terminal sequencing of the peptides obtained in highest yield revealed that the 4-thiouridine was cross-linked to lysine residues 402 and 439 in the primary sequence of MetRS. Since many prokaryotic tRNAs contain 4-thiouridine, the procedures described here should prove useful for identification of peptide sequences near this modified base when a variety of tRNAs are bound to specific proteins

  19. Prevalence of the A1555G (12S rRNA and tRNA Ser(UCN mitochondrial mutations in hearing-impaired Brazilian patients

    Abreu-Silva R.S.

    2006-01-01

    Full Text Available Mitochondrial mutations are responsible for at least 1% of the cases of hereditary deafness, but the contribution of each mutation has not yet been defined in African-derived or native American genetic backgrounds. A total of 203 unselected hearing-impaired patients were screened for the presence of the mitochondrial mutation A1555G in the 12S rRNA gene and mutations in the tRNA Ser(UCN gene in order to assess their frequency in the ethnically admixed Brazilian population. We found four individuals with A1555G mutation (2%, which is a frequency similar to those reported for European-derived populations in unselected samples. On the other hand, complete sequencing of the tRNA Ser(UCN did not reveal reported pathogenic substitutions, namely A7445G, 7472insC, T7510C, or T7511C. Instead, other rare substitutions were found such as T1291C, A7569G, and G7444A. To evaluate the significance of these findings, 110 "European-Brazilians" and 190 "African-Brazilians" unrelated hearing controls were screened. The T1291C, A7569G and G7444A substitutions were each found in about 1% (2/190 of individuals of African ancestry, suggesting that they are probably polymorphic. Our results indicate that screening for the A1555G mutation is recommended among all Brazilian deaf patients, while testing for mutations in the tRNA Ser(UCN gene should be considered only when other frequent deafness-causing mutations have been excluded or in the presence of a maternal transmission pattern.

  20. Gene conversion as a mechanism for divergence of a chloroplast tRNA gene inserted in the mitochondrial genome of Brassica oleracea.

    Dron, M; Hartmann, C; Rode, A.; Sevignac, M

    1985-01-01

    We have characterized a 1.7 kb sequence, containing a tRNA Leu2 gene shared by the ct and mt genomes of Brassica oleracea. The two sequences are completely homologous except in two short regions where two distinct gene conversion events have occurred between two sets of direct repeats leading to the insertion of 5 bp in the T loop of the mt copy of the ct gene. This is the first evidence that gene conversion represents the initial evolutionary step in inactivation of transferred ct genes in t...

  1. Elongation in translation as a dynamic interaction among the ribosome, tRNA, and elongation factors EF-G and EF-Tu

    Agirrezabala, Xabier; Frank, Joachim

    2009-01-01

    The ribosome is a complex macromolecular machine that translates the message encoded in the messenger RNA and synthesizes polypeptides by linking the individual amino acids carried by the cognate transfer RNAs (tRNAs). The protein elongation cycle, during which the tRNAs traverse the ribosome in a coordinated manner along a path of more than 100 Å, is facilitated by large-scale rearrangements of the ribosome. These rearrangements go hand in hand with conformational changes of tRNA as well as ...

  2. Impact of P-Site tRNA and antibiotics on ribosome mediated protein folding: studies using the Escherichia coli ribosome.

    Surojit Mondal

    Full Text Available BACKGROUND: The ribosome, which acts as a platform for mRNA encoded polypeptide synthesis, is also capable of assisting in folding of polypeptide chains. The peptidyl transferase center (PTC that catalyzes peptide bond formation resides in the domain V of the 23S rRNA of the bacterial ribosome. Proper positioning of the 3' -CCA ends of the A- and P-site tRNAs via specific interactions with the nucleotides of the PTC are crucial for peptidyl transferase activity. This RNA domain is also the center for ribosomal chaperoning activity. The unfolded polypeptide chains interact with the specific nucleotides of the PTC and are released in a folding competent form. In vitro transcribed RNA corresponding to this domain (bDV RNA also displays chaperoning activity. RESULTS: The present study explores the effects of tRNAs, antibiotics that are A- and P-site PTC substrate analogs (puromycin and blasticidin and macrolide antibiotics (erythromycin and josamycin on the chaperoning ability of the E. coli ribosome and bDV RNA. Our studies using mRNA programmed ribosomes show that a tRNA positioned at the P-site effectively inhibits the ribosome's chaperoning function. We also show that the antibiotic blasticidin (that mimics the interaction between 3'-CCA end of P/P-site tRNA with the PTC is more effective in inhibiting ribosome and bDV RNA chaperoning ability than either puromycin or the macrolide antibiotics. Mutational studies of the bDV RNA could identify the nucleotides U2585 and G2252 (both of which interact with P-site tRNA to be important for its chaperoning ability. CONCLUSION: Both protein synthesis and their proper folding are crucial for maintenance of a functional cellular proteome. The PTC of the ribosome is attributed with both these abilities. The silencing of the chaperoning ability of the ribosome in the presence of P-site bound tRNA might be a way to segregate these two important functions.

  3. Global Uranium And Thorium Resources: Are They Adequate To Satisfy Demand Over The Next Half Century?

    Lambert, I. B.

    2012-04-01

    This presentation will consider the adequacy of global uranium and thorium resources to meet realistic nuclear power demand scenarios over the next half century. It is presented on behalf of, and based on evaluations by, the Uranium Group - a joint initiative of the OECD Nuclear Energy Agency and the International Atomic Energy Agency, of which the author is a Vice Chair. The Uranium Group produces a biennial report on Uranium Resources, Production and Demand based on information from some 40 countries involved in the nuclear fuel cycle, which also briefly reviews thorium resources. Uranium: In 2008, world production of uranium amounted to almost 44,000 tonnes (tU). This supplied approximately three-quarters of world reactor requirements (approx. 59,000 tU), the remainder being met by previously mined uranium (so-called secondary sources). Information on availability of secondary sources - which include uranium from excess inventories, dismantling nuclear warheads, tails and spent fuel reprocessing - is incomplete, but such sources are expected to decrease in market importance after 2013. In 2008, the total world Reasonably Assured plus Inferred Resources of uranium (recoverable at less than 130/kgU) amounted to 5.4 million tonnes. In addition, it is clear that there are vast amounts of uranium recoverable at higher costs in known deposits, plus many as yet undiscovered deposits. The Uranium Group has concluded that the uranium resource base is more than adequate to meet projected high-case requirements for nuclear power for at least half a century. This conclusion does not assume increasing replacement of uranium by fuels from reprocessing current reactor wastes, or by thorium, nor greater reactor efficiencies, which are likely to ameliorate future uranium demand. However, progressively increasing quantities of uranium will need to be mined, against a backdrop of the relatively small number of producing facilities around the world, geopolitical uncertainties and

  4. Is Serum or Sputum Eosinophil Cationic Protein Level Adequate for Diagnosis of Mild Asthma?

    Mohammad Reza Khakzad

    2009-09-01

    Full Text Available Spirometry has been used as a common diagnostic test in asthma. Most of the patients with a mild asthma have a FEV1 within normal range. Hence, other diagnostic methods are usually used. The aim of this study was to evaluate whether eosinophil Cationic Protein (ECP could be an accurate diagnostic marker of mild asthma.In this study diagnosis of asthma was made according to internationally accepted criteria. Asthma severity was evaluated according to frequency of symptoms and FEV1. Adequate sputum samples were obtained in 50 untreated subjects. A control group of 12 normal subjects that showed PC20 more than 8 mg/dl was also examined. Sputum was induced by inhalation of hypertonic saline. Inflammatory cells in sputum smears were assessed semi-quantitatively. ECP and IgE concentrations, eosinophil (EO percentage and ECP/EO ratio in serum and sputum were also determined. The results revealed that Cough and dyspnea were the most frequent clinical findings. Dyspnea and wheezing were the symptoms that correlated with staging of asthma. FEV1 was within normal range (more than 80% of predicted in 22 (44% subjects.Asthmatic patients showed significantly higher numbers of blood eosinophils (4.5± 3.1% vs. 1.2±0.2%, P=0.009, and higher levels of serum ECP than control group (3.1± 2.6 % and 22.6± 15.8 ng/ml, respectively. Sputum ECP level in asthmatics was significantly higher than non- asthmatics (55.3±29.8ng/mL vs. 25.0±24.7ng/mL, P=0.045. Regression analysis showed no significant correlation between spirometric parameters and biomarkers, the only exception was significant correlation between FEF25-75 and serum ECP (r= 0.28, P 0.041. Regarding clinical symptoms, wheezing was significantly correlated with elevation of most of biomarkers. Since, serum and sputum ECP levels are elevated in untreated asthmatics, the ECP level could be used for accurate diagnosis of mild form of asthma in which spirometry is unremarkable.

  5. Is the Health of Irish Workers adequately protected from the effects Radon Gas?

    prosecuted for failing to comply with this legislation. Hence, the health of Irish workers is not being adequately protected from the effects of this silent killer, radon gas

  6. Biofunction-assisted DNA detection through RNase H-enhanced 3' processing of a premature tRNA probe in a wheat germ extract.

    Ogawa, Atsushi; Tabuchi, Junichiro; Doi, Yasunori; Takamatsu, Masashi

    2016-08-01

    We have developed a novel type of biofunction-assisted, signal-turn-on sensor for simply and homogenously detecting DNA. This sensor system is composed of two types of in vitro-transcribed label-free RNAs (a 3' premature amber suppressor tRNA probe and an amber-mutated mRNA encoding a reporter protein), RNase H, and a wheat germ extract (WGE). A target DNA induces the 3' end maturation of the tRNA probe, which is enhanced by RNase H and leads to the expression of a full-length reporter protein through amber suppression in WGE, while there is almost no expression without the target due to the inactivity of the premature probe. Therefore, the target can be readily detected with the activity of the translated reporter. The catalytic reuse of the target with the help of RNase H in addition to various bioprocesses in WGE enables this sensor system to exhibit relatively high selectivity and sensitivity. PMID:27289318

  7. A nutrient-driven tRNA modification alters translational fidelity and genome-wide protein coding across an animal genus.

    John M Zaborske

    2014-12-01

    Full Text Available Natural selection favors efficient expression of encoded proteins, but the causes, mechanisms, and fitness consequences of evolved coding changes remain an area of aggressive inquiry. We report a large-scale reversal in the relative translational accuracy of codons across 12 fly species in the Drosophila/Sophophora genus. Because the reversal involves pairs of codons that are read by the same genomically encoded tRNAs, we hypothesize, and show by direct measurement, that a tRNA anticodon modification from guanosine to queuosine has coevolved with these genomic changes. Queuosine modification is present in most organisms but its function remains unclear. Modification levels vary across developmental stages in D. melanogaster, and, consistent with a causal effect, genes maximally expressed at each stage display selection for codons that are most accurate given stage-specific queuosine modification levels. In a kinetic model, the known increased affinity of queuosine-modified tRNA for ribosomes increases the accuracy of cognate codons while reducing the accuracy of near-cognate codons. Levels of queuosine modification in D. melanogaster reflect bioavailability of the precursor queuine, which eukaryotes scavenge from the tRNAs of bacteria and absorb in the gut. These results reveal a strikingly direct mechanism by which recoding of entire genomes results from changes in utilization of a nutrient.

  8. Congenital encephalomyopathy and adult-onset myopathy and diabetes mellitus: Different phenotypic associations of a new heteroplasmic mtDNA tRNA glutamic acid mutation

    Hanna, M.G.; Nelson, I.; Sweeney, M.G.; Cooper, J.M.; Watkins, P.J.; Morgan-Hughes, J.A.; Harding, A.E. [Kings College Hospital, London (United Kingdom)

    1995-05-01

    We report the clinical, biochemical, and molecular genetic findings in a family with an unusual mitochondrial disease phenotype harboring a novel mtDNA tRNA glutamic acid mutation at position 14709. The proband and his sister presented with congenital myopathy and mental retardation and subsequently developed cerebellar ataxia. Other family members had either adult-onset diabetes mellitus with muscle weakness or adult-onset diabetes mellitus alone. Ragged-red and cytochrome c oxidase (COX)-negative fibers were present in muscle biopsies. Biochemical studies of muscle mitochondria showed reduced complex I and IV activities. The mtDNA mutation was heteroplasmic in blood and muscle in all matrilineal relatives analyzed. Primary myoblast, but not fibroblast, cultures containing high proportions of mutant mtDNA exhibited impaired mitochondrial translation. These observations indicate that mtDNA tRNA point mutations should be considered in the differential diagnosis of congenital myopathy. In addition they illustrate the diversity of phenotypes associated with this mutation in the same family and further highlight the association between mtDNA mutations and diabetes mellitus. 43 refs., 4 figs., 1 tab.

  9. Developmental origins of metabolic disorders: The need for biomarker candidates and therapeutic targets from adequate preclinical models

    Antonio Gonzalez-Bulnes

    2016-03-01

    Full Text Available The investigation on obesity and associated disorders have changed from an scenario in which genome drove the phenotype to a dynamic setup in which prenatal and early-postnatal conditions are determinant. However, research in human beings is difficult due to confounding factors (lifestyle and socioeconomic heterogeneity plus ethical issues. Hence, there is currently an intensive effort for developing adequate preclinical models, aiming for an adequate combination of basic studies in rodent models and specific preclinical studies in large animals. The results of these research strategies may increase the identification and development of contrasted biomarkers and therapeutic targets.

  10. Iodine Status of Women of Reproductive Age in Sierra Leone and Its Association with Household Coverage with Adequately Iodized Salt.

    Rohner, Fabian; Wirth, James P; Woodruff, Bradley A; Chiwile, Faraja; Yankson, Hannah; Sesay, Fatmata; Koroma, Aminata S; Petry, Nicolai; Pyne-Bailey, Solade; Dominguez, Elisa; Kupka, Roland; Hodges, Mary H; de Onis, Mercedes

    2016-02-01

    Salt iodization programs are a public health success in tackling iodine deficiency. Yet, a large proportion of the world's population remains at risk for iodine deficiency. In a nationally representative cross-sectional survey in Sierra Leone, household salt samples and women's urine samples were quantitatively analyzed for iodine content. Salt was collected from 1123 households, and urine samples from 817 non-pregnant and 154 pregnant women. Household coverage with adequately iodized salt (≥15 mg/kg iodine) was 80.7%. The median urinary iodine concentration (UIC) of pregnant women was 175.8 µg/L and of non-pregnant women 190.8 µg/L. Women living in households with adequately iodized salt had higher median UIC (for pregnant women: 180.6 µg/L vs. 100.8 µg/L, respectively, p education were much smaller in women living in households with adequately iodized salt than in households without. Despite the high household coverage of iodized salt in Sierra Leone, it is important to reach the 20% of households not consuming adequately iodized salt. Salt iodization has the potential for increasing equity in iodine status even with the persistence of other risk factors for deficiency. PMID:26848685

  11. Students' Use of Tutoring Services, by Adequate Yearly Progress Status of School. Statistics in Brief. NCES 2010-023

    Warkentien, Siri; Grady, Sarah

    2009-01-01

    This Statistics in Brief contributes to current research by investigating the use of tutoring services among a nationally representative group of public school students enrolled in grades K-12. The report compares students in schools that have not made Adequate Yearly Progress (AYP) for 3 or more years, and were thereby enrolled in schools that…

  12. Are Substance Use Prevention Programs More Effective in Schools Making Adequate Yearly Progress? A Study of Project ALERT

    Clark, Heddy Kovach; Ringwalt, Chris L.; Shamblen, Stephen R.; Hanley, Sean M.; Flewelling, Robert L.

    2011-01-01

    This exploratory study sought to determine if a popular school-based drug prevention program might be effective in schools that are making adequate yearly progress (AYP). Thirty-four schools with grades 6 through 8 in 11 states were randomly assigned either to receive Project ALERT (n = 17) or to a control group (n = 17); of these, 10 intervention…

  13. Iodine Status of Women of Reproductive Age in Sierra Leone and Its Association with Household Coverage with Adequately Iodized Salt

    Fabian Rohner

    2016-02-01

    Full Text Available Salt iodization programs are a public health success in tackling iodine deficiency. Yet, a large proportion of the world’s population remains at risk for iodine deficiency. In a nationally representative cross-sectional survey in Sierra Leone, household salt samples and women’s urine samples were quantitatively analyzed for iodine content. Salt was collected from 1123 households, and urine samples from 817 non-pregnant and 154 pregnant women. Household coverage with adequately iodized salt (≥15 mg/kg iodine was 80.7%. The median urinary iodine concentration (UIC of pregnant women was 175.8 µg/L and of non-pregnant women 190.8 µg/L. Women living in households with adequately iodized salt had higher median UIC (for pregnant women: 180.6 µg/L vs. 100.8 µg/L, respectively, p < 0.05; and for non-pregnant women: 211.3 µg/L vs. 97.8 µg/L, p < 0.001. Differences in UIC by residence, region, household wealth, and women’s education were much smaller in women living in households with adequately iodized salt than in households without. Despite the high household coverage of iodized salt in Sierra Leone, it is important to reach the 20% of households not consuming adequately iodized salt. Salt iodization has the potential for increasing equity in iodine status even with the persistence of other risk factors for deficiency.

  14. Using Fuzzy Logic to Identify Schools Which May Be Misclassified by the No Child Left Behind Adequate Yearly Progress Policy

    Yates, Donald W.

    2009-01-01

    This investigation developed, tested, and prototyped a Fuzzy Inference System (FIS) that would assist decision makers in identifying schools that may have been misclassified by existing Adequate Yearly Progress (AYP) methods. This prototype was then used to evaluate Louisiana elementary schools using published school data for Academic Year 2004. …

  15. Factors associated with adequate weekly reporting for disease surveillance data among health facilities in Nairobi County, Kenya, 2013

    Mwatondo, Athman Juma; Ng'ang'a, Zipporah; Maina, Caroline; Makayotto, Lyndah; Mwangi, Moses; Njeru, Ian; Arvelo, Wences

    2016-01-01

    Introduction Kenya adopted the Integrated Disease Surveillance and Response (IDSR) strategy in 1998 to strengthen disease surveillance and epidemic response. However, the goal of weekly surveillance reporting among health facilities has not been achieved. We conducted a cross-sectional study to determine the prevalence of adequate reporting and factors associated with IDSR reporting among health facilities in one Kenyan County. Methods Health facilities (public and private) were enrolled using stratified random sampling from 348 facilities prioritized for routine surveillance reporting. Adequately-reporting facilities were defined as those which submitted >10 weekly reports during a twelve-week period and a poor reporting facilities were those which submitted <10 weekly reports. Multivariate logistic regression with backward selection was used to identify risk factors associated with adequate reporting. Results From September 2 through November 30, 2013, we enrolled 175 health facilities; 130(74%) were private and 45(26%) were public. Of the 175 health facilities, 77 (44%) facilities classified as adequate reporting and 98 (56%) were reporting poorly. Multivariate analysis identified three factors to be independently associated with weekly adequate reporting: having weekly reporting forms at visit (AOR19, 95% CI: 6-65], having posters showing IDSR functions (AOR8, 95% CI: 2-12) and having a designated surveillance focal person (AOR7, 95% CI: 2-20). Conclusion The majority of health facilities in Nairobi County were reporting poorly to IDSR and we recommend that the Ministry of Health provide all health facilities in Nairobi County with weekly reporting tools and offer specific trainings on IDSR which will help designate a focal surveillance person. PMID:27303581

  16. The enigmatic mitochondrial genome of Rhabdopleura compacta (Pterobranchia reveals insights into selection of an efficient tRNA system and supports monophyly of Ambulacraria

    Stadler Peter F

    2011-05-01

    Full Text Available Abstract Background The Hemichordata comprises solitary-living Enteropneusta and colonial-living Pterobranchia, sharing morphological features with both Chordata and Echinodermata. Despite their key role for understanding deuterostome evolution, hemichordate phylogeny is controversial and only few molecular data are available for phylogenetic analysis. Furthermore, mitochondrial sequences are completely lacking for pterobranchs. Therefore, we determined and analyzed the complete mitochondrial genome of the pterobranch Rhabdopleura compacta to elucidate deuterostome evolution. Thereby, we also gained important insights in mitochondrial tRNA evolution. Results The mitochondrial DNA of Rhabdopleura compacta corresponds in size and gene content to typical mitochondrial genomes of metazoans, but shows the strongest known strand-specific mutational bias in the nucleotide composition among deuterostomes with a very GT-rich main-coding strand. The order of the protein-coding genes in R. compacta is similar to that of the deuterostome ground pattern. However, the protein-coding genes have been highly affected by a strand-specific mutational pressure showing unusual codon frequency and amino acid composition. This composition caused extremely long branches in phylogenetic analyses. The unusual codon frequency points to a selection pressure on the tRNA translation system to codon-anticodon sequences of highest versatility instead of showing adaptations in anticodon sequences to the most frequent codons. Furthermore, an assignment of the codon AGG to Lysine has been detected in the mitochondrial genome of R. compacta, which is otherwise observed only in the mitogenomes of some arthropods. The genomes of these arthropods do not have such a strong strand-specific bias as found in R. compacta but possess an identical mutation in the anticodon sequence of the tRNALys. Conclusion A strong reversed asymmetrical mutational constraint in the mitochondrial genome of

  17. Right pp Semigroups with Multiplicative Right Adequate Transversals%带有乘右适当断面的右主投射半群

    胡耀华; 郭小江

    2011-01-01

    In this paper, the concept of right adequate transversals of rpp semigroups is introduced. We establish the structure of rpp semigroups with multiplicative right adequate transversals in terms of right normal bands and right adequate semigroups. In particular, some special cases are considered.

  18. An RNA-binding complex involved in ribosome biogenesis contains a protein with homology to tRNA CCA-adding enzyme.

    Jinzhong Lin

    2013-10-01

    Full Text Available A multitude of proteins and small nucleolar RNAs transiently associate with eukaryotic ribosomal RNAs to direct their modification and processing and the assembly of ribosomal proteins. Utp22 and Rrp7, two interacting proteins with no recognizable domain, are components of the 90S preribosome or the small subunit processome that conducts early processing of 18S rRNA. Here, we determine the cocrystal structure of Utp22 and Rrp7 complex at 1.97 Å resolution and the NMR structure of a C-terminal fragment of Rrp7, which is not visible in the crystal structure. The structure reveals that Utp22 surprisingly resembles a dimeric class I tRNA CCA-adding enzyme yet with degenerate active sites, raising an interesting evolutionary connection between tRNA and rRNA processing machineries. Rrp7 binds extensively to Utp22 using a deviant RNA recognition motif and an extended linker. Functional sites on the two proteins were identified by structure-based mutagenesis in yeast. We show that Rrp7 contains a flexible RNA-binding C-terminal tail that is essential for association with preribosomes. RNA-protein crosslinking shows that Rrp7 binds at the central domain of 18S rRNA and shares a neighborhood with two processing H/ACA snoRNAs snR30 and snR10. Depletion of snR30 prevents the stable assembly of Rrp7 into preribosomes. Our results provide insight into the evolutionary origin and functional context of Utp22 and Rrp7.

  19. Anticodon recognition in evolution: switching tRNA specificity of an aminoacyl-tRNA synthetase by site-directed peptide transplantation.

    Brevet, Annie; Chen, Josiane; Commans, Stéphane; Lazennec, Christine; Blanquet, Sylvain; Plateau, Pierre

    2003-08-15

    The highly conserved aspartyl-, asparaginyl-, and lysyl-tRNA synthetases compose one subclass of aminoacyl-tRNA synthetases, called IIb. The three enzymes possess an OB-folded extension at their N terminus. The function of this extension is to specifically recognize the anticodon triplet of the tRNA. Three-dimensional models of bacterial aspartyl- and lysyl-tRNA synthetases complexed to tRNA indicate that a rigid scaffold of amino acid residues along the five beta-strands of the OB-fold accommodates the base U at the center of the anticodon. The binding of the adjacent anticodon bases occurs through interactions with a flexible loop joining strands 4 and 5 (L45). As a result, a switching of the specificity of lysyl-tRNA synthetase from tRNALys (anticodon UUU) toward tRNAAsp (GUC) could be attempted by transplanting the small loop L45 of aspartyl-tRNA synthetase inside lysyl-tRNA synthetase. Upon this transplantation, lysyl-tRNA synthetase loses its capacity to aminoacylate tRNALys. In exchange, the chimeric enzyme acquires the capacity to charge tRNAAsp with lysine. Upon giving the tRNAAsp substrate the discriminator base of tRNALys, the specificity shift is improved. The change of specificity was also established in vivo. Indeed, the transplanted lysyl-tRNA synthetase succeeds in suppressing a missense Lys --> Asp mutation inserted into the beta-lactamase gene. These results functionally establish that sequence variation in a small peptide region of subclass IIb aminoacyl-tRNA synthetases contributes to specification of nucleic acid recognition. Because this peptide element is not part of the core catalytic structure, it may have evolved independently of the active sites of these synthetases. PMID:12766171

  20. Diet quality of Italian yogurt consumers: an application of the probability of adequate nutrient intake score (PANDiet).

    Mistura, Lorenza; D'Addezio, Laura; Sette, Stefania; Piccinelli, Raffaela; Turrini, Aida

    2016-05-01

    The diet quality in yogurt consumers and non-consumers was evaluated by applying the probability of adequate nutrient intake (PANDiet) index to a sample of adults and elderly from the Italian food consumption survey INRAN SCAI 2005-06. Overall, yogurt consumers had a significantly higher mean intake of energy, calcium and percentage of energy from total sugars whereas the mean percentage of energy from total fat, saturated fatty acid and total carbohydrate were significantly (p yogurt consumers than in non-consumers, (60.58 ± 0.33 vs. 58.58 ± 0.19, p yogurt consumers. The items of calcium, potassium and riboflavin showed the major percentage variation between consumers and non-consumers. Yogurt consumers were more likely to have adequate intakes of vitamins and minerals, and a higher quality score of the diet. PMID:26906103

  1. The Leap of a Provincial SME into the Global Market Using E-commerce: The Success of Adequate Planning

    Sainz de Abajo, Beatriz; García Salcines, Enrique; Burón Fernández, F. Javier; López Coronado, Miguel; de Castro Lozano, Carlos

    The leap into the global market is not easy when it involves a provincial family business. This article demonstrates how adequate planning is fundamental in a small and medium-sized enterprise (SME) with the tight budget they have available to them, in order to be able to differentiate themselves in a highly competitive market, taking into accounts the benefits and risks involved. The Information Technology (IT) tools put in place will give the necessary support and allow for the possibility of increasing and improving the infrastructure as the company requires. An adequate strategy for the future to increases sales would be e-marketing techniques as well as the current promotions which contribute to diffusing the brand.

  2. INTERNAL AUDIT FOR FINANCIAL INVESTMENT COMPANIES – ASSURANCE FOR ADEQUATE SUPERVISING OF CORPORATE GOVERNENCE PRINCIPLES

    Tatiana Danescu; Ovidiu Spatacean

    2008-01-01

    In the risk assessment process, financial auditors often rely on internalauditors when establishing the control risk level. Therefore, adequate internal auditfunction, as part of a solid corporate governance is a factor of lowering control risk,when assessing audit risks for Financial Investment Companies. The paper intends toapproach issues related to internal audit as a relevant source of added value for listedcompanies and the main objectives related to internal audit engagements forFinanc...

  3. A model for determining when an analysis contains sufficient detail to provide adequate NEPA coverage for a proposed action

    Neither the National Environmental Policy Act (NEPA) nor its subsequent regulations provide substantive guidance for determining the Level of detail, discussion, and analysis that is sufficient to adequately cover a proposed action. Yet, decisionmakers are routinely confronted with the problem of making such determinations. Experience has shown that no two decisionmakers are Likely to completely agree on the amount of discussion that is sufficient to adequately cover a proposed action. one decisionmaker may determine that a certain Level of analysis is adequate, while another may conclude the exact opposite. Achieving a consensus within the agency and among the public can be problematic. Lacking definitive guidance, decisionmakers and critics alike may point to a universe of potential factors as the basis for defending their claim that an action is or is not adequately covered. Experience indicates that assertions are often based on ambiguous opinions that can be neither proved nor disproved. Lack of definitive guidance slows the decisionmaking process and can result in project delays. Furthermore, it can also Lead to inconsistencies in decisionmaking, inappropriate Levels of NEPA documentation, and increased risk of a project being challenged for inadequate coverage. A more systematic and less subjective approach for making such determinations is obviously needed. A paradigm for reducing the degree of subjectivity inherent in such decisions is presented in the following paper. The model is specifically designed to expedite the decisionmaking process by providing a systematic approach for making these determination. In many cases, agencies may find that using this model can reduce the analysis and size of NEPA documents

  4. PROBLEMS OF MAINTAINING ADEQUATE ACCOUNTING RECORDS FOR A NON-PROFIT ORGANIZATION IN SUB-SAHARAN AFRICA

    John R. Ledgerwood; Stephen N. Morgan

    2012-01-01

    This paper looks at the accounting challenges faced by a small-scale non-profit organization operating in sub-Saharan Africa. We will look at the case of Enright Flight Ministries, Inc. a 501(c)3 non-profit organization based in Florida that carries out evangelical and humanitarian aid projects in Zambia. Building upon field interviews with administrative staff and project managers, we analyze the various problems facing the organization in maintaining adequate accounting records. After looki...

  5. Survey of Third-Year Postgraduate Training Positions in Family Medicine: Adding more positions for adequate training in primary care

    Busing, Nick

    1992-01-01

    In a survey of 16 program directors of residency training in family medicine, respondents were asked about numbers and types of third-year positions they offer. As Canadian educational programs move toward implementing or expanding 2-year prelicensure requirements, many directors are exploring the need to add even more positions for adequate training in primary care. Respondents offered suggestions on tailoring strategies in view of the educational, political, and economic climate.

  6. A trilogy on. delta. -aminolevulinic acid biosynthesis in plants and algae: I. Glutamate is the sole precursor to protoheme and heme a in maize. II. The UUC glutamate anticodon is a general feature of the tRNA required for ALA biosynthesis. III. Protein and ALA biosynthesis use the same tRNA

    Schneegurt, M.A.

    1989-01-01

    Specifically radiolabeled substrates can be used to determine whether the heme and chlorophyll precursor {delta}-aminolevulinic acid (ALA) is synthesized via the fife-carbon pathway (incorporation from L-1-({sup 14}C)glutamate) or ALA synthase (incorporation from 2-({sup 14}C)glycine). In etiolated maize epicotyl sections, highly purified total cellular protoheme was labeled 29.7 times more effectively by glutamate than by glycine. Mitochondrial heme {alpha} was labeled 4.1 times more effectively by glutamate than by glycine. Cell-free plant and algal preparations require tRNA for the enzymatic conversion of glutamate to ALA. The tRNA required for ALA biosynthesis ahs been shown to contain the UUC glutamate anticodon, as determined by its specific retention through anticodon:anticodon interactions by tRNA{sup Phe(GAA)}-acrylamide. A fraction that was highly enriched in the RNA which supported ALA formation was obtained by affinity chromatography of RNA extracts from Chlorella vulgaris, Euglena garcilis, Cyanidium caldarium, Synechocystis, sp. PCC 6803, pea, and spinach. Other glutamate-accepting RNAs that were not retained by the affinity column were ineffective in supporting ALA formation.

  7. Are current practices adequate

    Events related to safeguards during the last year are reviewed. Present needs are a clear statement of safeguards objectives, more Federal funds, and design of facilities for easier safeguards. It is felt that effective safeguards can be implemented at relatively low overall cost to industry. C. Walske's presentation of the AIF position is strongly endorsed. (U.S.)

  8. Subjects with molecularly defined familial hypercholesterolemia or familial defective apoB-100 are not being adequately treated.

    Trond P Leren

    Full Text Available OBJECTIVES: To study whether subjects with a molecular genetic diagnosis of familial hypercholesterolemia (FH or familial defective apoB-100 (FDB are being adequately treated. DESIGN: A questionnaire regarding medical history was sent to 2611 subjects who had been provided with a molecular genetic diagnosis of FH or FDB, and a blood sample was obtained for lipid measurements. RESULTS: 956 (36.6% of the 2611 subjects participated. The mean age for starting lipid-lowering therapy was 33.4 (±12.1 years. Among those below 18 years of age, only 20.4% were on lipid-lowering drugs, whereas 89.1% of those aged 18 and above were on lipid-lowering drugs. The mean levels of total serum cholesterol and LDL-cholesterol were 5.7 (±1.5 mmol/l and 3.9 (±1.3 mmol/l, respectively. Among those who were on lipid-lowering drugs, 29.0% and 12.2% had levels of LDL cholesterol below 3.0 mmol/l and 2.6 mmol/l, respectively. Only 47.3% of the 956 subjects were considered as being adequately treated largely due to a failure to titrate their drug regimens. From the use of cholesterol-years score, lipid-lowering therapy must start before the age of 20 in order to prevent the subjects from contracting premature coronary heart disease. CONCLUSION: The majority of FH/FDB subjects are being diagnosed late in life and are not being adequately treated. In order to prevent them from contracting premature coronary heart disease, it is key that levels of LDL cholesterol are normalized from a young age and that sufficient doses of lipid-lowering drugs are being used.

  9. Phentolamine as a treatment for poor mixing in transposition of the great arteries with adequate intraatrial communication.

    Galal, M O; El-Naggar, W I; Sharfi, M H

    2005-01-01

    Patients with transposition of the great arteries often show poor mixing for different reasons, even after adequate balloon atrial septostomy. We present a patient with such a lesion whose clinical status improved dramatically after phentolamine was applied. We believe this improvement is due to reduction in afterload caused by the alpha(2) blocker and also possibly as a response to a presumptive effect of the drug on the diastolic function of the right ventricle, allowing more left-to-right shunt across the atrial septal defect. Both phenomena can improve cardiac output in such a situation. PMID:16374695

  10. On the influence of adequate Weddell Sea characteristics in a large-scale global ocean circulation model

    Hellmer, Hartmut; Schodlok, Michael; Wenzel, Manfred; Schröter, Jens

    2005-01-01

    Global ocean circulation models usually lack an adequate consideration of high-latitude processes due to a limited model domain or insufficient resolution. Without the processes in key areas of the global thermohaline circulation, the characteristics and flow of deep and bottom waters cannot be modeled realistically. In this study, a high-resolution (~20 km) ocean model focused on the Weddell Sea sector of the Southern Ocean is combined with a low-resolution (2°× 2°) global ocean model applyi...

  11. Median Urinary Iodine Concentrations Are Indicative of Adequate Iodine Status among Women of Reproductive Age in Prey Veng, Cambodia.

    Karakochuk, Crystal D; Michaux, Kristina D; Chai, Tze L; Chan, Benny B; Whitfield, Kyly C; Barr, Susan I; McLean, Judy; Talukder, Aminuzzaman; Hou, Kroeun; Ly, Sokhoing; Green, Tim J

    2016-03-01

    Iodine deficiency disorders are estimated to affect over 1.9 million people worldwide. Iodine deficiency is especially serious for women during pregnancy and lactation because of the negative consequences for both mother and infant. The aim of this cross-sectional study was to determine the median urinary iodine concentration (UIC) as a population-level indicator of iodine status among rural women farmers of reproductive age (18-45 years) in the province of Prey Veng, Cambodia. A total of 450 women provided a spot morning urine sample in 2012. Of those women, 93% (n = 420) were non-pregnant and 7% (n = 30) were pregnant at the time of collection. UIC was quantified using the Sandell-Kolthoff reaction with modifications. The median UIC of non-pregnant (139 μg/L) and pregnant women (157 μg/L) were indicative of adequate iodine status using the WHO/UNICEF/ICCIDD epidemiological criteria for both groups (median UIC between 100-199 and 150-249 μg/L, respectively). We conclude that non-pregnant and pregnant women in rural Prey Veng, Cambodia had adequate iodine status based on single spot morning urine samples collected in 2012. More research is warranted to investigate iodine status among larger and more representative populations of women in Cambodia, especially in light of recent policy changes to the national program for universal salt iodization. PMID:26950151

  12. New pleiotropic effects of eliminating a rare tRNA from Streptomyces coelicolor, revealed by combined proteomic and transcriptomic analysis of liquid cultures

    Hotchkiss Graham

    2007-08-01

    Full Text Available Abstract Background In Streptomyces coelicolor, bldA encodes the only tRNA for a rare leucine codon, UUA. This tRNA is unnecessary for growth, but is required for some aspects of secondary metabolism and morphological development. We describe a transcriptomic and proteomic analysis of the effects of deleting bldA on cellular processes during submerged culture: conditions relevant to the industrial production of antibiotics. Results At the end of rapid growth, a co-ordinated transient up-regulation of about 100 genes, including many for ribosomal proteins, was seen in the parent strain but not the ΔbldA mutant. Increased basal levels of the signal molecule ppGpp in the mutant strain may be responsible for this difference. Transcripts or proteins from a further 147 genes classified as bldA-influenced were mostly expressed late in culture in the wild-type, though others were significantly transcribed during exponential growth. Some were involved in the biosynthesis of seven secondary metabolites; and some have probable roles in reorganising metabolism after rapid growth. Many of the 147 genes were "function unknown", and may represent unknown aspects of Streptomyces biology. Only two of the 147 genes contain a TTA codon, but some effects of bldA could be traced to TTA codons in regulatory genes or polycistronic operons. Several proteins were affected post-translationally by the bldA deletion. There was a statistically significant but weak positive global correlation between transcript and corresponding protein levels. Different technical limitations of the two approaches were a major cause of discrepancies in the results obtained with them. Conclusion Although deletion of bldA has very conspicuous effects on the gross phenotype, the bldA molecular phenotype revealed by the "dualomic" approach has shown that only about 2% of the genome is affected; but this includes many previously unknown effects at a variety of different levels, including post

  13. A survey of green plant tRNA 3'-end processing enzyme tRNase Zs, homologs of the candidate prostate cancer susceptibility protein ELAC2

    Wang Zhikang

    2011-07-01

    Full Text Available Abstract Background tRNase Z removes the 3'-trailer sequences from precursor tRNAs, which is an essential step preceding the addition of the CCA sequence. tRNase Z exists in the short (tRNase ZS and long (tRNase ZL forms. Based on the sequence characteristics, they can be divided into two major types: bacterial-type tRNase ZS and eukaryotic-type tRNase ZL, and one minor type, Thermotoga maritima (TM-type tRNase ZS. The number of tRNase Zs is highly variable, with the largest number being identified experimentally in the flowering plant Arabidopsis thaliana. It is unknown whether multiple tRNase Zs found in A. thaliana is common to the plant kingdom. Also unknown is the extent of sequence and structural conservation among tRNase Zs from the plant kingdom. Results We report the identification and analysis of candidate tRNase Zs in 27 fully sequenced genomes of green plants, the great majority of which are flowering plants. It appears that green plants contain multiple distinct tRNase Zs predicted to reside in different subcellular compartments. Furthermore, while the bacterial-type tRNase ZSs are present only in basal land plants and green algae, the TM-type tRNase ZSs are widespread in green plants. The protein sequences of the TM-type tRNase ZSs identified in green plants are similar to those of the bacterial-type tRNase ZSs but have distinct features, including the TM-type flexible arm, the variant catalytic HEAT and HST motifs, and a lack of the PxKxRN motif involved in CCA anti-determination (inhibition of tRNase Z activity by CCA, which prevents tRNase Z cleavage of mature tRNAs. Examination of flowering plant chloroplast tRNA genes reveals that many of these genes encode partial CCA sequences. Based on our results and previous studies, we predict that the plant TM-type tRNase ZSs may not recognize the CCA sequence as an anti-determinant. Conclusions Our findings substantially expand the current repertoire of the TM-type tRNase ZSs and hint

  14. Poor neurological sequelae of herpes simplex virus encephalitis in an infant despite adequate antiviral and adjunct corticosteroid therapy

    Ratna B Basak

    2011-01-01

    Full Text Available A 2-month-old infant presented to our emergency department with fever, altered consciousness, and focal seizures of acute onset. He had vesicular skin lesions over the right preauricular region. CT brain showed a large hypodense lesion involving the left temporo-parietal region, left basal ganglia and left thalamus. MRI brain revealed bilateral multifocal corticomedullary lesions suggestive of encephalitis. CSF-PCR was positive for herpes simplex virus (HSV type I. He was treated with standard dose intravenous acyclovir for 15 days along with a trial of pulse methylprednisolone, but was readmitted within a week with features of an early relapse. The infant survived but developed significant neurological sequelae. Although treatment of HSV is available, the neurological outcome is guarded even with adequate antiviral therapy. Adjunct corticosteroid therapy did not appear to attenuate the neurological sequelae.

  15. Are radon gas measurements adequate for epidemiological studies and case control studies of radon-induced lung cancer?

    The lung dose derived from radon is not attributed to the radon gas itself, but instead to its short-lived progeny. However, in many epidemiological studies as well as in case control studies of the radon risk, the excess number of cancers are related to the radon gas exposure, and not to the radon progeny exposure. A justification for such an approach has resorted to the assumption that there is self-compensation between the radiation doses from the unattached and attached fractions. In the present study, we used the Jacobi model to calculate the radon progeny concentrations in a room by varying the attachment rate and then calculated the resulting lung dose. It was found that self-compensation was not fully realised, and the effective dose can vary by a factor up to ∼2 for the same radon gas concentration. In conclusion, the radon gas concentration alone does not provide adequate information on the effective dose. (authors)

  16. 鸡硒蛋白T的硒代半胱氨酸插入序列元件、蛋白结构与功能及组织表达差异%Analysis of selenocysteine insertion sequence element, structures and functions and expression profiles of selenoprotein T in chicken

    葛延松; 曹嫦妤; 王丽丽; 李楠; 江秀清; 李金龙

    2014-01-01

    应用生物软件分析鸡和其他11种脊椎动物硒蛋白 T ( selenoprotein T ,SelT )的硒代半胱氨酸插入序列( selenocysteine insertion sequence , SECIS)元件、SelT核苷酸和氨基酸序列的同源性,并分析鸡SelT 的结构及功能;采用实时荧光定量PCR( fluorescent quantitative real-time PCR , fqRT-PCR)方法检测SelT基因在35日龄鸡体内30种组织中的表达谱.结果显示:脊椎动物 SelT的SECIS元件均属于Ⅱ型结构;鸡 SelT核苷酸序列与其他11种脊椎动物的同源性在48.0%~85.1%之间,而氨基酸序列与非洲爪蟾、斑马鱼的同源性低于90.0%,与其他9种动物的同源性在90.6%~94.9%之间;鸡 SelT 属于跨膜蛋白,存在信号肽,属于 RDx 家族,酶活性分类为EC 2.5.1.18,具有氧化还原功能,且存在Ca2+结合位点.SelT在鸡各组织中广泛表达,在睾丸中含量极其丰富,提示鸡SelT在雄性生殖系统中可能发挥功能.%Selenium ( Se) was an important , biologically necessary trace element , which played an important biological roles in avian growth , reproduction , immune function and disease resistance . The biological significance of Se was attributed to its occurrence in selenoproteins in the form of selenocysteine ( Sec) with a 21 amino acid genetic code . Se uses the stop codon UGA as the coding codon encoding Sec . Selenoproteins involved in many life processes such as antioxidant defense , cell signal transduction , metabolic pathway , development , immune function , and hormone regulates , and it was related to the occurrence and mechanism of many diseases . Selenoprotein T (SelT) was originally identified through silico studies ,cloned and expressed in a mammalian cell line ,confirmed as a selenoprotein . Previous studies have proved that SelT mainly occurred in Golgi apparatus and endoplasmic reticulum , with important biological function . SelT can act on the Ca2+ homeostasis , involved in neuroendocrine secretion . SelT has

  17. Adequate dietary vitamin D and calcium are both required to reduce bone turnover and increased bone mineral volume.

    Lee, Alice M C; Sawyer, Rebecca K; Moore, Alison J; Morris, Howard A; O'Loughlin, Peter D; Anderson, Paul H

    2014-10-01

    Clinical studies indicate that the combination of vitamin D and dietary calcium supplementation is more effective for reducing fracture risk than either supplement alone. Our previous dietary studies demonstrated that an adequate serum 25-hydroxyvitamin D3 (25D) of 80nmol/L or more reduces bone RANKL expression, osteoclastogenesis and maintains the optimal levels of trabecular bone volume (BV/TV%) in young rats. The important clinical question of the interaction between vitamin D status, dietary calcium intake and age remains unclear. Hence, 9 month-old female Sprague-Dawley rats (n=5-6/group) were pair-fed a semi-synthetic diet containing varying levels of vitamin D (0, 2, 12 or 20IU/day) and dietary calcium (0.1% or 1%) for 6 months. At 15 months of age, animals were killed, for biochemical and skeletal analyses. While changes to serum 25D were determined by both dietary vitamin D and calcium levels, changes to serum 1,25-dihydroxyvitamin D3 (1,25D) were consistently raised in animals fed 0.1% Ca regardless of dietary vitamin D or vitamin D status. Importantly, serum cross-laps levels were significantly increased in animals fed 0.1% Ca only when combined with 0 or 2 IUD/day of vitamin D, suggesting a contribution of both dietary calcium and vitamin D in determining bone resorption activity. Serum 25(OH)D3 levels were positively correlated with both femoral mid-diaphyseal cortical bone volume (R(2)=0.24, PTV% (R(2)=0.23, Pnegative determinant of CBV (R(2)=0.24, PTV% levels. These data support clinical data that reduced bone resorption and increased bone volume can only be achieved with adequate 25D levels in combination with high dietary calcium and low serum 1,25D levels. This article is part of a Special Issue entitled '16th Vitamin D Workshop'. PMID:24309068

  18. Familial clustering strongly suggests that the phenotypic variation of the 8344 A>G lys mitochondrial tRNA mutation is encoded in cis.

    Kazakos, Kyriakos; Kotsa, Kalliopi; Yavropoulou, Maria; Dionyssopoulos, Alexander; Grabs, Rosemary; Yovos, John; Polychronakos, Constantin

    2012-07-01

    The maternally inherited 8344 A>G mutation in the mitochondrial Lys tRNA is classically associated with the myoclonic epilepsy, ragged-red muscle fiber (MERRF) syndrome. Multiple lipomatosis (Madelung's disease) is occasionally described. Here we report a large kindred with a statistically significant clustering of very unusual clinical manifestations. We have studied a Greek family that includes seven symptomatic cases of 8344 A>G. Clinical features, glucose tolerance and heteroplasmy in fat, muscle and blood were analyzed. The patients, aged 34-76 at the time of assessment, all suffer from progressive proximal limb-girdle myopathy and extensive lipomatosis. Four of the seven have either impaired glucose tolerance or diabetes but none has had epilepsy, a cardinal feature of MERRF. Heteroplasmy was not higher in adipose tissue than that found in the literature. Compared to literature reports, the familial clustering of this unusual combination of manifestations (lipomatosis in all, epilepsy in none) is statistically significant. The clustering of unusual manifestations in this large kindred strongly suggests that much of the phenotypic variability of 8344 A>G is determined by mitochondrially encoded modifiers in cis. PMID:22681518

  19. The impact of mitochondrial tRNA mutations on the amount of ATP synthase differs in the brain compared to other tissues.

    Fornuskova, Daniela; Brantova, Olga; Tesarova, Marketa; Stiburek, Lukas; Honzik, Tomas; Wenchich, Laszlo; Tietzeova, Evzenie; Hansikova, Hana; Zeman, Jiri

    2008-05-01

    The impact of point mutations in mitochondrial tRNA genes on the amount and stability of respiratory chain complexes and ATP synthase (OXPHOS) has been broadly characterized in cultured skin fibroblasts, skeletal muscle samples, and mitochondrial cybrids. However, less is known about how these mutations affect other tissues, especially the brain. We have compared OXPHOS protein deficiency patterns in skeletal muscle mitochondria of patients with Leigh (8363G>A), MERRF (8344A>G), and MELAS (3243A>G) syndromes. Both mutations that affect mt-tRNA(Lys) (8363G>A, 8344A>G) resulted in severe combined deficiency of complexes I and IV, compared to an isolated severe defect of complex I in the 3243A>G sample (mt-tRNA(LeuUUR). Furthermore, we compared obtained patterns with those found in the heart, frontal cortex, and liver of 8363G>A and 3243A>G patients. In the frontal cortex mitochondria of both patients, the patterns of OXPHOS deficiencies differed substantially from those observed in other tissues, and this difference was particularly striking for ATP synthase. Surprisingly, in the frontal cortex of the 3243A>G patient, whose ATP synthase level was below the detection limit, the assembly of complex IV, as inferred from 2D-PAGE immunoblotting, appeared to be hindered by some factor other than the availability of mtDNA-encoded subunits. PMID:18319067

  20. Crystallization and preliminary X-ray analysis of the tRNA thiolation enzyme MnmA from Escherichia coli complexed with tRNA{sup Glu}

    Numata, Tomoyuki [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan); Ikeuchi, Yoshiho [Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Fukai, Shuya [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan); Adachi, Hiroaki [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); Department of Electrical, Electronic and Information Engineering, Osaka University, Osaka 567-0047 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Matsumura, Hiroyoshi [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); Department of Materials Chemistry, Osaka University, Osaka 567-0047 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Takano, Kazufumi [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Department of Material and Life Science, Osaka University, Osaka 567-0047 (Japan); Murakami, Satoshi [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Institute of Scientific and Industrial Research, Osaka University, Osaka 567-0047 (Japan); PRESTO, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Inoue, Tsuyoshi [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); Department of Materials Chemistry, Osaka University, Osaka 567-0047 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Mori, Yusuke; Sasaki, Takatomo [SOSHO Inc., 7-7-15-208 Asagi, Saito, Ibaraki, Osaka 567-0085 (Japan); Department of Electrical, Electronic and Information Engineering, Osaka University, Osaka 567-0047 (Japan); CREST, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); Suzuki, Tsutomu [Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Nureki, Osamu, E-mail: onureki@bio.titech.ac.jp [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan); PRESTO, JST, Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan); RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045 (Japan)

    2006-04-01

    The RNA thiouridylase MnmA in complex with tRNA was crystallized with and without ATP in three different crystal forms, which may reflect distinct sulfuration-reaction stages. MnmA catalyzes a sulfuration reaction to synthesize 2-thiouridine at the wobble positions of tRNA{sup Glu}, tRNA{sup Gln} and tRNA{sup Lys} in Escherichia coli. The binary complex of MnmA and tRNA{sup Glu} was crystallized in two different crystal forms: forms I and II. Cocrystallization of MnmA–tRNA{sup Glu} with ATP yielded form III crystals. The three crystal forms diffracted to 3.1, 3.4 and 3.4 Å resolution, respectively, using synchrotron radiation at SPring-8. These crystals belong to space groups C2, I2{sub 1}2{sub 1}2{sub 1} and C2, with unit-cell parameters a = 225.4, b = 175.8, c = 53.0 Å, β = 101.6°, a = 101.5, b = 108.0, c = 211.2 Å and a = 238.1, b = 102.1, c = 108.2 Å, β = 117.0°, respectively. The asymmetric units of these crystals are expected to contain two, one and two MnmA–tRNA{sup Glu} complexes, respectively.

  1. The two-layer geochemical structure of modern biogeochemical provinces and its significance for spatially adequate ecological evaluations and decisions

    Korobova, Elena; Romanov, Sergey

    2014-05-01

    Contamination of the environment has reached such a scale that ecogeochemical situation in any area can be interpreted now as a result of the combined effect of natural and anthropogenic factors. The areas that appear uncomfortable for a long stay can have natural and anthropogenic genesis, but the spatial structure of such biogeochemical provinces is in any case formed of a combination of natural and technogenic fields of chemical elements. Features of structural organization and the difference in factors and specific time of their formation allow their separation on one hand and help in identification of areas with different ecological risks due to overlay of the two structures on the other. Geochemistry of soil cover reflects the long-term result of the naturally balanced biogeochemical cycles, therefore the soil geochemical maps of the undisturbed areas may serve the basis for evaluation of the natural geochemical background with due regard to the main factors of geochemical differentiation in biosphere. Purposeful and incidental technogenic concentrations and dispersions of chemical elements of specific (mainly mono- or polycentric) structure are also fixed in soils that serve as secondary sources of contamination of the vegetation cover and local food chains. Overlay of the two structures forms specific heterogeneity of modern biogeochemical provinces with different risk for particular groups of people, animals and plants adapted to specific natural geochemical background within particular concentration interval. The developed approach is believed to be helpful for biogeochemical regionalizing of modern biosphere (noosphere) and for spatially adequate ecogeochemical evaluation of the environment and landuse decisions. It allows production of a set of applied geochemical maps such as: 1) health risk due to chemical elements deficiency and technogenic contamination accounting of possible additive effects; 2) adequate soil fertilization and melioration with due

  2. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    de Lange, W. J.

    2014-05-01

    Wim J. de Lange, Geert F. Prinsen, Jacco H. Hoogewoud, Ab A Veldhuizen, Joachim Hunink, Erik F.W. Ruijgh, Timo Kroon Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses

  3. African HIV/AIDS trials are more likely to report adequate allocation concealment and random generation than North American trials.

    Nandi Siegfried

    Full Text Available BACKGROUND: Adherence to good methodological quality is necessary to minimise bias in randomised conrolled trials (RCTs. Specific trial characteristics are associated with better trial quality, but no studies to date are specific to HIV/AIDS or African trials. We postulated that location may negatively impact on trial quality in regions where resources are scarce. METHODS: 1 To compare the methodological quality of all HIV/AIDS RCTs conducted in Africa with a random sample of similar trials conducted in North America; 2 To assess whether location is predictive of trial quality. We searched MEDLINE, EMBASE, CENTRAL and LILACS. Eligible trials were 1 randomized, 2 evaluations of preventive or treatment interventions for HIV/AIDS, 3 reported before 2004, and 4 conducted wholly or partly (if multi-centred in Africa or North America. We assessed adequacy of random generation, allocation concealment and masking of assessors. Using univariate and multivariate logistic regression analyses we evaluated the association between location (Africa versus North America and these domains. FINDINGS: The African search yielded 12,815 records, from which 80 trials were identified. The North American search yielded 13,158 records from which 785 trials were identified and a random sample of 114 selected for analysis. African trials were three times more likely than North American trials to report adequate allocation concealment (OR = 3.24; 95%CI: 1.59 to 6.59; p<0.01 and twice as likely to report adequate generation of the sequence (OR = 2.36; 95%CI: 1.20 to 4.67; p = 0.01, after adjusting for other confounding factors. Additional significant factors positively associated with quality were an a priori sample size power calculation, restricted randomization and inclusion of a flow diagram detailing attrition. We did not detect an association between location and outcome assessor masking. CONCLUSIONS: The higher quality of reporting of methodology in African trials is

  4. Fair Balance and Adequate Provision in Direct-to-Consumer Prescription Drug Online Banner Advertisements: A Content Analysis

    2016-01-01

    Background The current direct-to-consumer advertising (DTCA) guidelines were developed with print, television, and radio media in mind, and there are no specific guidelines for online banner advertisements. Objective This study evaluates how well Internet banner ads comply with existing Food and Drug Administration (FDA) guidelines for DTCA in other media. Methods A content analysis was performed of 68 banner advertisements. A coding sheet was developed based on (1) FDA guidance documents for consumer-directed prescription drug advertisements and (2) previous DTCA content analyses. Specifically, the presence of a brief summary detailing the drug’s risks and side effects or of a “major statement” identifying the drug’s major risks, and the number and type of provisions made available to consumers for comprehensive information about the drug were coded. In addition, the criterion of “fair balance,” the FDA’s requirement that prescription drug ads balance information relating to the drug’s risks with information relating to its benefits, was measured by numbering the benefit and risk facts identified in the ads and by examining the presentation of risk and benefit information. Results Every ad in the sample included a brief summary of risk information and at least one form of adequate provision as required by the FDA for broadcast ads that do not give audiences a brief summary of a drug’s risks. No ads included a major statement. There were approximately 7.18 risk facts for every benefit fact. Most of the risks (98.85%, 1292/1307) were presented in the scroll portion of the ad, whereas most of the benefits (66.5%, 121/182) were presented in the main part of the ad. Out of 1307 risk facts, 1292 were qualitative and 15 were quantitative. Out of 182 benefit facts, 181 were qualitative and 1 was quantitative. The majority of ads showed neutral images during the disclosure of benefit and risk facts. Only 9% (6/68) of the ads displayed positive images and

  5. Detailed NMR, Including 1,1-ADEQUATE, and Anticancer Studies of Compounds from the Echinoderm Colobometra perspinosa

    Catherine H. Liptrot

    2009-11-01

    Full Text Available From the dichloromethane/methanol extract of the crinoid Colobometra perspinosa, collected south east of Richards Island (Bedara, Family Islands, Central Great Barrier Reef, Australia, 3-(1'-hydroxypropyl-1,6,8-trihydroxy-9,10-anthraquinone [one of the two stereoisomers of rhodoptilometrin, (1], 3-propyl-1,6,8-trihydroxy-9,10-anthraquinone (3, 2-[(phenylacetylamino]ethanesulfonic acid (4, and 4-hydroxybutanoic acid (5 were isolated. Comparison of 1H- and 13C-NMR data for rhodoptilometrin (1 with those reported in the literature showed significant differences for some resonances associated with rings A and C. In an attempt to provide accurately assigned 1H- and 13C-NMR data, as well as to confirm the structure of 1, a thorough NMR investigation of this compound was undertaken. Measurements included: concentration dependent 13C, 1D selective NOE, HSQC, HMBC and 1,1-ADEQUATE. The NMR data for 4 and 5 are reported here for the first time, as is their occurrence from the marine environment. The in vitro anticancer activity of the original extract was found to be associated with 1, 3 and 5.

  6. New vessel formation in the context of cardiomyocyte regeneration – the role and importance of an adequate perfusing vasculature

    Katherine C. Michelis

    2014-11-01

    Full Text Available The history of revascularization for cardiac ischemia dates back to the early 1960’s when the first coronary artery bypass graft procedures were performed in humans. With this 50 year history of providing a new vasculature to ischemic and hibernating myocardium, a profound depth of experience has been amassed in clinical cardiovascular medicine as to what does, and does not work in the context of cardiac revascularization, alleviating ischemia and adequacy of myocardial perfusion. These issues are of central relevance to contemporary cell-based cardiac regenerative approaches. While the cardiovascular cell therapy field is surging forward on many exciting fronts, several well accepted clinical axioms related to the cardiac arterial supply appear to be almost overlooked by some of our current basic conceptual and experimental cell therapy paradigms. We present here information drawn from five decades of the clinical revascularization experience, review relevant new data on vascular formation via cell therapy, and put forward the case that for optimal cell-based cardiac regeneration due attention must be paid to providing an adequate vascular supply.

  7. The Initiator Methionine tRNA Drives Secretion of Type II Collagen from Stromal Fibroblasts to Promote Tumor Growth and Angiogenesis.

    Clarke, Cassie J; Berg, Tracy J; Birch, Joanna; Ennis, Darren; Mitchell, Louise; Cloix, Catherine; Campbell, Andrew; Sumpton, David; Nixon, Colin; Campbell, Kirsteen; Bridgeman, Victoria L; Vermeulen, Peter B; Foo, Shane; Kostaras, Eleftherios; Jones, J Louise; Haywood, Linda; Pulleine, Ellie; Yin, Huabing; Strathdee, Douglas; Sansom, Owen; Blyth, Karen; McNeish, Iain; Zanivan, Sara; Reynolds, Andrew R; Norman, Jim C

    2016-03-21

    Expression of the initiator methionine tRNA (tRNAi(Met)) is deregulated in cancer. Despite this fact, it is not currently known how tRNAi(Met) expression levels influence tumor progression. We have found that tRNAi(Met) expression is increased in carcinoma-associated fibroblasts, implicating deregulated expression of tRNAi(Met) in the tumor stroma as a possible contributor to tumor progression. To investigate how elevated stromal tRNAi(Met) contributes to tumor progression, we generated a mouse expressing additional copies of the tRNAi(Met) gene (2+tRNAi(Met) mouse). Growth and vascularization of subcutaneous tumor allografts was enhanced in 2+tRNAi(Met) mice compared with wild-type littermate controls. Extracellular matrix (ECM) deposited by fibroblasts from 2+tRNAi(Met) mice supported enhanced endothelial cell and fibroblast migration. SILAC mass spectrometry indicated that elevated expression of tRNAi(Met) significantly increased synthesis and secretion of certain types of collagen, in particular type II collagen. Suppression of type II collagen opposed the ability of tRNAi(Met)-overexpressing fibroblasts to deposit pro-migratory ECM. We used the prolyl hydroxylase inhibitor ethyl-3,4-dihydroxybenzoate (DHB) to determine whether collagen synthesis contributes to the tRNAi(Met)-driven pro-tumorigenic stroma in vivo. DHB had no effect on the growth of syngeneic allografts in wild-type mice but opposed the ability of 2+tRNAi(Met) mice to support increased angiogenesis and tumor growth. Finally, collagen II expression predicts poor prognosis in high-grade serous ovarian carcinoma. Taken together, these data indicate that increased tRNAi(Met) levels contribute to tumor progression by enhancing the ability of stromal fibroblasts to synthesize and secrete a type II collagen-rich ECM that supports endothelial cell migration and angiogenesis. PMID:26948875

  8. Mutation of the gene encoding the ribonuclease P RNA in the hyperthermophilic archaeon Thermococcus kodakarensis causes decreased growth rate and impaired processing of tRNA precursors.

    Ueda, Toshifumi; Ishino, Sonoko; Suematsu, Kotaro; Nakashima, Takashi; Kakuta, Yoshimitsu; Kawarabayasi, Yutaka; Ishino, Yoshizumi; Kimura, Makoto

    2015-12-25

    Ribonuclease P (RNase P) catalyzes the processing of 5' leader sequences of tRNA precursors in all three phylogenetic domains. RNase P also plays an essential role in non-tRNA biogenesis in bacterial and eukaryotic cells. For archaeal RNase Ps, additional functions, however, remain poorly understood. To gain insight into the biological function of archaeal RNase Ps in vivo, we prepared archaeal mutants KUWΔP3, KUWΔP8, and KUWΔP16, in which the gene segments encoding stem-loops containing helices, respectively, P3, P8 and P16 in RNase P RNA (TkopRNA) of the hyperthermophilic archaeon Thermococcus kodakarensis were deleted. Phenotypic analysis showed that KUWΔP3 and KUWΔP16 grew slowly compared with wild-type T. kodakarensis KUW1, while KUWΔP8 displayed no difference from T. kodakarensis KUW1. RNase P isolated using an affinity-tag from KUWΔP3 had reduced pre-tRNA cleavage activity compared with that from T. kodakarensis KUW1. Moreover, quantitative RT-PCR (qRT-PCR) and Northern blots analyses of KUWΔP3 showed greater accumulation of unprocessed transcripts for pre-tRNAs than that of T. kodakarensis KUW1. The current study represents the first attempt to prepare mutant T. kodakarensis with impaired RNase P for functional investigation. Comparative whole-transcriptome analysis of T. kodakarensis KUW1 and KUWΔP3 should allow for the comprehensive identification of RNA substrates for archaeal RNase Ps. PMID:26551464

  9. Phytase improves apparent total tract digestibility of phosphorus and calcium in piglets fed diets with adequate or reduced phosphorus content.

    Kühn, I; Partanen, K

    2012-12-01

    The effect of a thermotolerant 6-phytase produced by Trichoderma reesei on performance and apparent total tract digestibility (ATTD) of P and Ca was evaluated in 192 weaned piglets (randomized block design; 16 replicates; 2 piglets each). Diets based on wheat (Triticum aestivum), barley (Hordeum vulgare), oat (Avena sativa), soybean (Glycine max) meal, and whey protein with adequate [positive control (PC)] or reduced [negative control (NC)] Ca and P levels were fed for 46 d after weaning. The PC and NC diets contained 8.0 and 6.4 g/kg Ca and 2.9 and 1.9 g/kg digestible P, respectively. Pelleted diets contained 0, 500, or 1000 phytase units (FTU)/kg. Growth performance and G:F were measured during starter (25 d) and weaner pig (21 d) periods. The ATTD of Ca and P was determined by spot sampling at the end of the weaner pig period (8 pens per treatment over 5 consecutive d). Data were analyzed using a mixed model with random block effect and fixed effect of dietary P and phytase level and their interaction. Dietary P level did not affect ADG or G:F of piglets over the entire feeding period (P > 0.10) whereas phytase increased G:F (P feed DM) without further increase in the weaner pig period (P > 0.10). A P × phytase interaction (P < 0.05) was observed for ATTD of P, more so for NC (48, 61, and 68%, respectively) than PC diets (52, 62, and 61%). The ATTD of Ca was higher (P < 0.05) for PC than NC diets (68 vs. 58%) and increased quadratically by phytase (61, 65, and 63%). In conclusion, the phytase tested enhanced piglet performance during the postweaning period and increased ATTD of P and Ca. PMID:23365327

  10. Two distinct domains of the β subunit of Aquifex aeolicus leucyl-tRNA synthetase are involved in tRNA binding as revealed by a three-hybrid selection

    Zheng, Yong-Gang; Wei, Hui; Ling, Chen; Martin, Franck; Eriani, Gilbert; Wang, En-Duo

    2004-01-01

    The Aquifex aeolicus αβ-LeuRS is the only known heterodimeric class Ia aminoacyl-tRNA synthetase. In this study, we investigated the function of the β subunit which is believed to bind tRNALeu. A yeast three-hybrid system was constructed on the basis of the interaction of the β subunit with its cognate tRNALeu. Then, seven mutated β subunits exhibiting impaired tRNA binding capacities were selected out from a randomly mutated library. Two mutations were identified in the class Ia-helix-bundle...

  11. O7.02RADIOSURGERY AND BRAIN METASTASES: ADEQUATE SEQUENCE OF BRAIN MRI CAN SIGNIFICANTLY CHANGE THE INTRACRANIAL DISEASE STAGING

    Scoccianti, S.; Greto, D.; Bordi, L.; Bono, P.; Pecchioli, G.; Casati, M.; Vanzi, E.; Compagnucci, A.; Gadda, D.; Livi, L.

    2014-01-01

    INTRODUCTION: Accurate assessment of the exact number of brain metastases is of utmost importance in the decision-making process for the appropriate treatment. The diagnostic efficacy in the detection of additional brain metastases of a double dose contrast three-dimensional, T1-Weighted Gradient-Echo Imaging was evaluated. METHODS: Before undergoing radiosurgical treatment, patients underwent a brain magnetic resonance imaging (MRI) scan to be used during the treatment planning in order to contour the targets and to locate the brain lesions as they relate to the stereotactic frame. All the patients underwent a post-contrast study with T1-weighted, 3D Magnetization-Prepared Rapid Acquisition Gradient Echo (MP RAGE) sequence. We used a double dose of gadobenate dimeglumine and slice thickness of 0.9 mm. RESULTS: Starting from October 2012 to February 2014, we treated with Gamma Knife radiosurgery (GKRS) 62 patients with brain metastases. On the diagnostic MRI, all the patients had a number of lesions ≤4. Median time interval between diagnostic MRI scan and the day of GKRS was 11 days (range 5-20) A total of 54 additional lesions were detected on MR imaging performed in the same day of the GKRS in twenty-two patients out of 62 (35.5%). A median number of 2 additional lesions were detected (range 1-8). Among these 22 patients only 14 patients had a number of lesions ≤4 on the day of treatment. Patients with a total number of lesions ≤10 were treated with GKRS. Two patients with a total number of lesions > 10 were treated with whole brain radiotherapy (WBRT). CONCLUSIONS: A double-contrast study with T1-weighted, volumetric MPRAGE sequence may offer better staging for patients with brain metastases. In our opinion, it should be recommended in all the patients with newly diagnosed brain metastases because the detection of the real number of lesions is crucial for an adequate treatment and it also may lead to choose different therapeutic strategies.

  12. AnnAGNPS model as a potential tool for seeking adequate agriculture land management in Navarre (Spain)

    Chahor, Y.; Giménez, R.; Casalí, J.

    2012-04-01

    runoff was. On the other hand, a significant increment (30%) on annual sediment yield was predicted when rapeseed is the alternative major crop. Besides, a large decrease in annual runoff (up to 41%) and sediment (up to 98%) was predicted as the watershed is gradually occupied by shrubs. Finally, no-tillage appears as an interesting management method for cereals, with an over 90% reduction of in sediment yield -but only 4% in runoff. This is a first approach to evaluate AnnAGNPS as a management tool under local conditions. The above results may be then taking with caution especially in terms of absolute predicted values. However, AnnAGNPS can be considered as a promising tool for assessing the effect of the agricultural activities and implementing adequate land management alternatives in Mediterranean environment.

  13. Adequate cutoff frequency of the prefilter in quantification of regional cerebral blood flow using 123I-IMP

    The effect of cutoff frequency (CF) of the butterworth filter was studied in the quantification of regional cerebral blood flow (rCBF) by N-isopropyl-P-[123I]-iodoamphetamine (123I-IMP) auto-radiography (ARG) to determine the adequate cutoff value by comparison with XeCT/CBF. The single photon emission computed tomography (SPECT) machine was Toshiba 3-detector GCA-9300A/PI equipped with a low energy high resolution fanbeam collimator and data processor GMS-5500A/PI, on which the butterworth filter was loaded. SPECT data acquisition was performed 18-48 min after 123I-IMP injection, and the data and blood radioactivity at 10 min measured by Aloka auto-well counter ARC-300 were used for calculating rCBF (ARG/CBF) values. The CCP-II phantom for the cross calibration factor (CCF) was purchased from Sangyo Kagaku Co., Ltd. and was filled with 123I-IMP (10 kBq/mL). The CT machine was Toshiba X-vigor, and CT with Xenon gas (XeCT) was done with the products of Anzai Sogyo aspirator AZ-725 and data processor AZ-7000. XeCT data acquisition was performed by 4 min aspiration/4 min washout of the gas (Xe 30%, O2 70%) and XeCT/CBF values were calculated with the processor AZ-7000. Data were selected from 80 patients (M 46, average age 62.1 y) with chronic diseases of cerebral blood vessels, in whom ARG/CBF and XeCT/CBF tests had been conducted within a week. Examined were the relationships between CF (0.523-0.930 cycles/cm) vs CCF; CF vs ARG/CBF, where rCBF was defined to be at regions of the middle cerebral artery, thalamus and cerebral ventricle; ARG/CBF vs XeCT/CBF at CF of 0.581-0.930, where the correlation coefficient (r) and slope were evaluated for decision of the optimal CF value. Under conditions employed, CBF values varied with the CF and its optimal value was found to be 0.814 cycles/cm with a best fitted slope. (T.T.)

  14. Assurance of an adequate handling of test items in the laboratory in charge of the tritium analyses in Havana, Cuba

    storage of samples in the Laboratory is in charge of executing this procedure, informing to the quality manager about any found anomaly so that can be taken the corresponding correctives actions. All nonconformity and correctives actions are written in the Record of nonconformity of the Laboratory (RNP/LVRA/12). In the Quality Manual of the Laboratory is declared that the laboratory witness samples will be handled according to that exposed in the PR/LVRA/01 and that it is necessary to guarantee appropriate storage conditions for these samples, according to the requirements of assay. In this case, it is also the responsible for the storage of the samples in the Laboratory the person in charge of fulfilling these functions. In the General Procedure of the Laboratory (PR/LVRA/02) the whole journey of the samples in the Laboratory for its assay, as well as the accompanying records and the quality controls to carry out in each step of the process, is described. At last, the standardized model in the laboratory for report the results establishes that the same entrance identification code of samples should appear. In the same way, in the Record of samples (RNP/LVRA/01) appear the code of the report the result, corresponding to the assay that is carried out to each sample. The established process diagrams at Laboratory in order to guarantee an adequate handling of test items are exposed in a detailed way in this work. (author)

  15. Distribution of classical and nonclassical virulence genes in enterotoxigenic Escherichia coli isolates from Chilean children and tRNA gene screening for putative insertion sites for genomic islands.

    Del Canto, Felipe; Valenzuela, Patricio; Cantero, Lidia; Bronstein, Jonathan; Blanco, Jesús E; Blanco, Jorge; Prado, Valeria; Levine, Myron; Nataro, James; Sommerfelt, Halvor; Vidal, Roberto

    2011-09-01

    Enterotoxigenic Escherichia coli (ETEC) is an important cause of diarrhea. Three adhesins (Tia, TibA, EtpA), an iron acquisition system (Irp1, Irp2, and FyuA), a GTPase (LeoA), and an autotransporter (EatA) are ETEC virulence-related proteins that, in contrast to the classical virulence factors (enterotoxins and fimbrial colonization factors) have not heretofore been targets in characterizing isolates from epidemiological studies. Here, we determined the occurrence of these nonclassical virulence genes in 103 ETEC isolates from Chilean children with diarrhea and described their association with O serogroups and classical virulence determinants. Because tia, leoA, irp2, and fyuA are harbored by pathogenicity islands inserted into the selC and asnT tRNA genes (tDNAs), we analyzed the regions flanking these loci. Ten additional tDNAs were also screened to identify hot spots for genetic insertions. Associations between the most frequent serogroups and classical colonization factor (CF)-toxin profiles included O6/LT-STh/CS1-CS3-CS21 (i.e., O6 serogroup, heat-labile [LT] and human heat-stable [STh] enterotoxins, and CFs CS1, -3 and -21), O6/LT-STh/CS2-CS3-CS21, and O104-O127/STh/CFAI-CS21. The eatA and etpA genes were detected in more than 70% of the collection, including diverse serogroups and virulence profiles. Sixteen percent of the ETEC strains were negative for classical and nonclassical adhesins, suggesting the presence of unknown determinants of adhesion. The leuX, thrW, and asnT tDNAs were disrupted in more than 65% of strains, suggesting they are hot spots for the insertion of mobile elements. Sequences similar to integrase genes were identified next to the thrW, asnT, pheV, and selC tDNAs. We propose that the eatA and etpA genes should be included in characterizations of ETEC isolates in future epidemiological studies to determine their prevalence in other geographical regions. Sequencing of tDNA-associated genetic insertions might identify new ETEC virulence

  16. Characterization of a novel chaperone/usher fimbrial operon present on KpGI-5, a methionine tRNA gene-associated genomic island in Klebsiella pneumoniae

    van Aartsen Jon J

    2012-04-01

    Full Text Available Abstract Background Several strain-specific Klebsiella pneumoniae virulence determinants have been described, though these have almost exclusively been linked with hypervirulent liver abscess-associated strains. Through PCR interrogation of integration hotspots, chromosome walking, island-tagging and fosmid-based marker rescue we captured and sequenced KpGI-5, a novel genomic island integrated into the met56 tRNA gene of K. pneumoniae KR116, a bloodstream isolate from a patient with pneumonia and neutropenic sepsis. Results The 14.0 kb KpGI-5 island exhibited a genome-anomalous G + C content, possessed near-perfect 46 bp direct repeats, encoded a γ1-chaperone/usher fimbrial cluster (fim2 and harboured seven other predicted genes of unknown function. Transcriptional analysis demonstrated expression of three fim2 genes, and suggested that the fim2A-fim2K cluster comprised an operon. As fimbrial systems are frequently implicated in pathogenesis, we examined the role of fim2 by analysing KR2107, a streptomycin-resistant derivative of KR116, and three isogenic mutants (Δfim, Δfim2 and ΔfimΔfim2 using biofilm assays, human cell adhesion assays and pair-wise competition-based murine models of intestinal colonization, lung infection and ascending urinary tract infection. Although no statistically significant role for fim2 was demonstrable, liver and kidney CFU counts for lung and urinary tract infection models, respectively, hinted at an ordered gradation of virulence: KR2107 (most virulent, KR2107∆fim2, KR2107∆fim and KR2107∆fim∆fim2 (least virulent. Thus, despite lack of statistical evidence there was a suggestion that fim and fim2 contribute additively to virulence in these murine infection models. However, further studies would be necessary to substantiate this hypothesis. Conclusion Although fim2 was present in 13% of Klebsiella spp. strains investigated, no obvious in vitro or in vivo role for the locus was identified, although

  17. The importance of adequate follow-up in defining treatment success after external beam irradiation for prostate cancer

    median follow-up of 3 years for this cohort (range: 1 to 5 years). This process was repeated five times for five random samples of seven cohorts each. Biochemical failure was calculated according to the Consensus Panel definition. Results: In the first analysis, significantly different rates of biochemical control (varying by 6-21%) were calculated for the same actuarial year chosen for analysis depending only upon the length of follow-up used. For example, the 3-year actuarial rate of biochemical control (BC) varied from 71% when calculated with 3 years of follow-up versus 50.4% with 7 years (p < 0.01). These differences in actuarial rates of BC were observed in all subsets of patients analyzed (e.g., PSA < 10, Gleason ≤ 6, n = 132, p < 0.001; PSA < 10, Gleason ≥ 7, n = 33, p = 0.03; PSA ≥ 10, Gleason ≤ 6, n = 109, p < 0.001; and PSA ≥ 10, Gleason ≥ 7, n = 72, p = 0.002). The absolute magnitude of the difference in actuarial rates of BC was greatest during years 2 (range 18-30%), 3 (range 16-25%), and 4 (range 15-24%) after treatment. In the second analysis using median PSA follow-ups (as defined above), statistically significant differences in actuarial rates of BC were again observed. For example, the 3-year actuarial rate of BC varied from 74.8% with a median follow-up of 2 years versus 49.2% with a median follow-up of 6 years. These dramatic differences in BC were still observed beyond 5 years. Conclusion: When the ASTRO Consensus Panel definition of BF is used to calculate treatment success with external beam RT for prostate cancer, adequate follow-up is critical. Depending upon the length of time after treatment, significantly different rates of BC (varying by 15% to 30%) can be calculated for the same time interval chosen for analysis. These results suggest that data should only be reported if the length of follow-up extends at least beyond the time point at which actuarial results are examined for the majority of patients

  18. Heating cells in acid methanol for 30 min without freeze-drying provides adequate yields of fatty acids and alcohols for gas chromatographic characterization of mycobacteria.

    Jimenez, J; Larsson, L

    1986-01-01

    We studied the release of mycobacterial fatty acids (as methyl esters) and secondary alcohols after heating both wet and freeze-dried cells in methanolic hydrogen chloride for different time periods. A 30-min heating of the mycobacteria without prior freeze-drying was found adequate in a routine gas chromatographic procedure for strain and species characterization.

  19. Intelligence, Academic Self-Concept, and Information Literacy: The Role of Adequate Perceptions of Academic Ability in the Acquisition of Knowledge about Information Searching

    Rosman, Tom; Mayer, Anne-Kathrin; Krampen, Günter

    2015-01-01

    Introduction: The present paper argues that adequate self-perceptions of academic ability are essential for students' realization of their intellectual potential, thereby fostering learning of complex skills, e.g., information-seeking skills. Thus, academic self-concept should moderate the relationship between intelligence and information…

  20. THE INFLUENCE FACTORS OF POWER AND OWNERSHIP ON THE FORMATION OF CONFIGURATIONS OF THE CAPITALS OF THE MODERN CORPORATION, ADEQUATE TO THE CHARACTERISTICS OF DEVELOPMENT

    Yermolenko V. V.

    2015-12-01

    Full Text Available The article examines the influence of key factors in the development of modern corporations – the authorities and property for the effective realization of the expanded reproduction of generative type. The article reveals a problem of building an effective configuration of capital (capitalograms and an adequate system of existing development strategies of a corporation. It also formulates research hypothesis

  1. How to Use PAP (Pain-Avoidance Principle) to Make AYP (Adequate Yearly Progress) under NCLB (No Child Left Behind Act)

    Popham, W. James

    2005-01-01

    Today's educators live in fear of the draconian consequences of failing to make adequate yearly progress under the No Child Left Behind Act. In this article, the author offers sage advice on how to "comply" with the law and not get hurt. In this analysis, the author also offers guidance to his public school colleagues who, yearning to dodge the…

  2. Mutation Analysis of Mitochondrial tRNA Gene in Patients with Primary Dilated Cardiomyopathy%原发性扩张型心肌病的线粒体tRNA基因突变分析

    李红超; 舒红英; 李晓杰; 倪斌; 谢海龙; 周海燕; 倪崖

    2015-01-01

    To identify the potential pathogenic mutations of mitochondrial tRNA in patients with primary dilated cardio-myopathy(DCM) and the possible association of the mutations with DCM.Paraffin-embedded myocardial tissues from two patients with DCM and 10 healthy controls,which were discarded after forensic examination,were used for the study.PCR amplification wasperformed for the mitochondrial tRNA genes and direct sequencing was conducted.Sequencing re-sults showed no variation for mitochondrial tRNA genes in the normal myocardial tissues.The tRNAVal G1664A variation and tRNAMet T4454C variation were identified in patients with DCM.These two variations were previously reported as polymorphism in MitoMap.There was no pathogenic mutation detected in mitochondrial tRNA genes of the two patients with DCM.A patient pool of large sample size is expected for analysis of the pathogenic mutations,polymorphism loci and haplogroup that might be associated with DCM.%为寻找原发性扩张型心肌病病例是否存在已知以及未知的线粒体tRNA致病性突变,以探讨扩张型心肌病可能的发病原因.收集2例原发性扩张型心肌病患者和10例正常对照尸检心肌组织石蜡标本,针对22种线粒体tRNA基因分别设计一对引物,PCR扩增后并测序分析线粒体tRNA基因突变情况.结果在对照样本中未检测到线粒体tRNA变异位点,在1例患者中检测到了tRNAVal基因G1664A变异,Mitomap已有报道为多态性位点;于另1例患者中检测到tRNAMetT4454C变异,有文章报道该位点与线粒体功能障碍有关,Mitomap报道为多态性位点.本研究中2例病例中未检测到线粒体tRNA致病性突变位点,可能与病例个体的心衰程度有关,有必要扩大样本量深入研究线粒体tRNA以及mtDNA其他基因突变与原发性扩张型心肌病之间的关系,以寻找可能的致病突变位点、易感的多态性位点或者单倍体群,为认识原发性扩张型心肌病的发病机制进一步提供理论基础和依据.

  3. Assessment of adequate quality and collocation of reference measurements with space-borne hyperspectral infrared instruments to validate retrievals of temperature and water vapour

    Calbet, X.

    2016-01-01

    A method is presented to assess whether a given reference ground-based point observation, typically a radiosonde measurement, is adequately collocated and sufficiently representative of space-borne hyperspectral infrared instrument measurements. Once this assessment is made, the ground-based data can be used to validate and potentially calibrate, with a high degree of accuracy, the hyperspectral retrievals of temperature and water vapour.

  4. Multiple giant succular and fusiform right and left coronary artery aneurysms after early and adequate treatment of atypical kawasaki disease with unusual presentation.

    Mostafa Behjati-Ardakani

    2014-06-01

    Full Text Available The major complication of Kawasaki disease is coronary artery dilatation and aneurysm. It occurs in approximately 15-25% of untreated children with Kawasaki Disease. Early diagnosis and treatment with Intravenous immune globulin (IVIG and aspirin (ASA can reduce the incidence of coronary artery abnormality to 2%-5%. We report one case of Atypical Kawasaki Disease with Multiple giant coronary artery aneurysms despite early adequate treatment with IVIG and ASA.

  5. Evaluation of a Diet Quality Index Based on the Probability of Adequate Nutrient Intake (PANDiet) Using National French and US Dietary Surveys

    Verger, Eric O.; François Mariotti; Holmes, Bridget A.; Damien Paineau; Jean-François Huneau

    2012-01-01

    Background: Existing diet quality indices often show theoretical and methodological limitations, especially with regard to validation. [br/] Objective: To develop a diet quality index based on the probability of adequate nutrient intake (PANDiet) and evaluate its validity using data from French and US populations. Material and Methods: The PANDiet is composed of adequacy probabilities for 24 nutrients grouped into two sub-scores. The relationship between the PANDiet score and energy intake...

  6. Water for food: a human rights obligation : How states can manage conflicts between the human right to water and the human right to adequate food

    Windfuhr, Michael

    2013-01-01

    While the right to water is a universal human right, water resources are limited. The single largest consumer of water globally is agriculture with its function to safeguard the right to adequate food. At the same time, water resources available for human consumption are decreasing, and more and more countries face water shortages. Conflicts related to water will become a serious issue. Local authorities as well as state governments need to develop mechanisms and criteria that allow them ...

  7. Artemether-lumefantrine treatment failure despite adequate lumefantrine day 7 concentration in a traveller with Plasmodium falciparum malaria after returning from Tanzania.

    Färnert Anna; Ursing Johan; Tolfvenstam Thomas; Rono Josea; Karlsson Lillemor; Sparrelid Elda; Lindegårdh Niklas

    2012-01-01

    Abstract Artemether-lumefantrine is currently first-line therapy of Plasmodium falciparum malaria in many countries. This report describes a treatment failure despite adequate drug concentrations in a traveller returning from sub-Saharan Africa. Genotyping confirmed recrudescence and suggested reduced sensitivity. Potential sub-optimal effect of artemether-lumefantrine highlights the need to follow non-immune individuals the weeks after treatment.

  8. Artemether–lumefantrine treatment failure despite adequate lumefantrine day 7 concentration in a traveller with Plasmodium falciparum malaria after returning from Tanzania

    Färnert Anna

    2012-05-01

    Full Text Available Abstract Artemether-lumefantrine is currently first-line therapy of Plasmodium falciparum malaria in many countries. This report describes a treatment failure despite adequate drug concentrations in a traveller returning from sub-Saharan Africa. Genotyping confirmed recrudescence and suggested reduced sensitivity. Potential sub-optimal effect of artemether-lumefantrine highlights the need to follow non-immune individuals the weeks after treatment.

  9. Assessment of medical students’ proficiency in dermatology: Are medical students adequately prepared to diagnose and treat common dermatologic conditions in the United States?

    Catherine A Ulman

    2015-05-01

    Full Text Available This study assessed whether a current medical school curriculum is adequately preparing medical students to diagnose and treat common dermatologic conditions. A 15-item anonymous multiple choice quiz covering fifteen diseases was developed to test students’ ability to diagnose and treat common dermatologic conditions. The quiz also contained five items that assessed students’ confidence in their ability to diagnose common dermatologic conditions, their perception of whether they were receiving adequate training in dermatology, and their preferences for additional training in dermatology. The survey was performed in 2014, and was completed by 85 students (79.4%. Many students (87.6% felt that they received inadequate training in dermatology during medical school. On average, students scored 46.6% on the 15-item quiz. Proficiency at the medical school where the study was performed is considered an overall score of greater than or equal to 70.0%. Students received an average score of 49.9% on the diagnostic items and an average score of 43.2% on the treatment items. The findings of this study suggest that United States medical schools should consider testing their students and assessing whether they are being adequately trained in dermatology. Then schools can decide if they need to re-evaluate the timing and delivery of their current dermatology curriculum, or whether additional curriculum hours or clinical rotations should be assigned for dermatologic training.

  10. Are currently GFR estimating equations and standard Kt/V value adequate for advanced chronic kidney disease (CKD) frail elderly patients?

    Musso, Carlos G; Alvarez-Gregori, Joaquin; Jauregui, Jose; Núñez, Juan F Macías

    2015-07-01

    Chronic kidney disease (CKD) elderly patients have a reduced glomerular filtration rate (GFR) due to the combination of ageing and chronic nephropathy damage. This situation is very important to be taken into account in order to prescribe an adequate medication and dialysis dose in this aged group. Besides, cognitive and urinary incontinence problems make difficult to obtain an adequate 24-h urine collection in order to evaluate creatinine clearance in this group. Thus, a reliable GFR estimating equation would be very useful for assisting elderly CKD patients. Additionally, Kt/V is the main parameter currently used for dosing dialysis in stage V CKD young and elderly patients. However, frailty and sarcopenia are prevalent disorders usually suffered by old people, who also present many physiological changes that could make GFR estimating equations and standard Kt/V value to become unreliable in this particular group. In conclusion, based on all these facts, it seems crucial for clinical geriatric nephrology to carefully evaluate how reliable current GFR estimating equations are, as well as which would be an adequate Kt/V value in CKD frail elderly patients. PMID:25993909

  11. Adequate hydrogen sulfide, healthy circulation

    DU Jun-bao; CHEN Stella; JIN Hong-fang; TANG Chao-shu

    2011-01-01

    Previously,hydrogen sulfide (H2S) was considered to be a toxic gas.However,recently it was discovered that it could be produced in mammals and even in plants,throughtheproductionandmetabolismof sulfur-containing amino acids.In mammals,H2S is mainly catalyzed by cystathionine-γ-lyase (CSE),cystathionin-β-lyase (CBS) and 3-mercaptopyruvate sulfurtransferase (MPST) with the substrate of L-cysteine.Endogenous H2S exerts many important physiological and pathophysiological functions,including hypotensive action,vasorelaxation,myocardial dilation,inhibition of smooth muscle cell proliferation,and antioxidatve actions.Importantly,it plays a very important role in the pathogenesis of systemic hypertension,pulmonary hypertension,atherosclerosis,myocardialinjury,angiogenesis,hyperhomocysteinemi aandshock.Therefore,H2S is now being considered to be a novel gasotransmitter after nitric oxide and carbon monoxide in the regulation of circulatory system.

  12. The Right to Adequate Nutrition

    Olivier de Schutter

    2014-01-01

    Four important conceptual shifts have occurred in our understanding of under- and malnutrition in recent years. Together, they have led to the emergence of the concept of ‘food and nutrition security’ and to a renewed emphasis not on calorie intake alone, but also on the adequacy of diets and care. Human rights provide a useful framework for ensuring food and nutrition security. However, only through more democracy in the food systems can change happen.

  13. Adequate procedures for specific exams

    Some ideal procedures for specific radiographic exams are briefly presented. The aim is to improve the quality standard, establishing a specific method for each exam in order to decrease films waste and reduce the patient dose exposure

  14. How Feasible is Adequate Yearly Progress (AYP)? Simulations of School AYP "Uniform Averaging" and "Safe Harbor" under the No Child Left Behind Act

    Jaekyung Lee

    2004-01-01

    The No Child Left Behind Act of 2001 (NCLB) requires that schools make “adequate yearly progress” (AYP) towards the goal of having 100 percent of their students become proficient by year 2013-14. Through simulation analyses of Maine and Kentucky school performance data collected during the 1990s, this study investigates how feasible schools would have met the AYP targets if the mandate had been applied in the past with “uniform averaging (rolling averages)” and “safe harbor” options that have...

  15. Access to adequate housing - a way out of poverty? : A minor field study of the construction of emergency houses in Peru.

    Berglund, Gabriella; Porthén, Petra

    2012-01-01

    Background: The lack of access to adequate housing is a major problem in many developing countries. One of the countries where the housing deficit is a big problem is Peru. The housing deficit in the country can be estimated to more than one million; a number that represents almost 15% of the country’s households. Un Techo Para Mi País (UTPMP) strives to improve this difficult housing situation by constructing emergency houses in the human settlements and thereby improving the situation for t...

  16. Hard- and software of real time simulation tools of Electric Power System for adequate modeling power semiconductors in voltage source convertor based HVDC and FACTS

    Ufa Ruslan A.

    2014-01-01

    Full Text Available The motivation of the presented research is based on the needs for development of new methods and tools for adequate simulation of Flexible Alternating Current Transmission System (FACTS devices and High Voltage Direct Current Transmission (HVDC system as part of real electric power systems (EPS. For that, a hybrid approach for advanced simulation of the FACTS and HVDC based on Voltage Source is proposed. The presented simulation results of the developed hybrid model of VSC confirm the achievement of the desired properties of the model and the effectiveness of the proposed solutions.

  17. Violence as an Under-Recognized Barrier to Women's Realization of Their Right to Adequate Food and Nutrition: Case Studies From Georgia and South Africa.

    Bellows, Anne C; Lemke, Stefanie; Jenderedjian, Anna; Scherbaum, Veronika

    2015-10-01

    This article addresses under-acknowledged barriers of structural violence and discrimination that interfere with women's capacity to realize their human rights generally, and their right to adequate food and nutrition in particular. Case studies from Georgia and South Africa illustrate the need for a human rights-based approach to food and nutrition security that prioritizes non-discrimination, public participation, and self-determination. These principles are frustrated by different types of structural violence that, if not seriously addressed, pose multiple barriers to women's economic, public, and social engagement. PMID:26139694

  18. Reduced bone mineral density is not associated with significantly reduced bone quality in men and women practicing long-term calorie restriction with adequate nutrition

    Villareal, Dennis T; Kotyk, John J.; Armamento-Villareal, Reina C.; Kenguva, Venkata; Seaman, Pamela; Shahar, Allon; Wald, Michael J.; Kleerekoper, Michael; Fontana, Luigi

    2010-01-01

    Calorie restriction (CR) reduces bone quantity but not bone quality in rodents. Nothing is known regarding the long-term effects of CR with adequate intake of vitamin and minerals on bone quantity and quality in middle-aged lean individuals. In this study, we evaluated body composition, bone mineral density (BMD), and serum markers of bone turnover and inflammation in 32 volunteers who had been eating a CR diet (~35% less calories than controls) for an average of 6.8±5.2 years (mean age 52.7±...

  19. Adequate vitamin D levels in a Swedish population living above latitude 63°N: The 2009 Northern Sweden MONICA study

    Anna Ramnemark

    2015-05-01

    Full Text Available Background: Even though vitamin D is mainly produced by exposure to sunlight, little is known regarding vitamin D levels in populations living in sub-Arctic areas with little or no daylight during winter. Objective: We describe distributions of vitamin D3 and the prevalence of adequate levels in a population living above 63°N. Design: We sampled 1,622 randomly selected subjects, aged 25–74 years, between January and May, 2009, as part of the Northern Sweden MONICA study (69.2% participation rate. By using HPLC, 25(OH vitamin D3 was analysed. Levels used for definitions were deficient, D3<25 nmol/l (<10 ng/ml; insufficient, D3 25–49.9 nmol/l (10–20 ng/ml; and adequate, D3≥50 nmol/l (20 ng/ml. Results: Mean (median level of vitamin D3 was 65.2 (63.6 nmol/l in men and 71.0 (67.7 nmol/l in women. Adequate levels were found in 79.2%, more often in women (82.7% than in men (75.6%. Only 0.7% of the population were vitamin D3–deficient but 23.1% of men and 17.1% of women had insufficient levels. Levels of vitamin D3 increased with age and insufficient status was most common among those aged 25–34 years, 41.0% in men and 22.3% in women.If subjects using vitamin D-supplementation are excluded, the population level of D3 is 1–2 nmol/l lower than in the general population across sex- and age groups. There were no differences between the northern or the southern parts, between urban or rural living or according to educational attainment. Those subjects born outside of Sweden or Finland had lower levels. Conclusion: The large majority living close to the Arctic Circle in Sweden have adequate D3 levels even during the second half of the dark winter. Subjects with D3 deficiency were uncommon but insufficient levels were often found among young men.

  20. Adequate vitamin D levels in a Swedish population living above latitude 63°N : The 2009 Northern Sweden MONICA study

    Ramnemark, Anna; Norberg, Margareta; Petterson-Kymmer, Ulrika; Eliasson, Mats

    2015-01-01

    Background. Even though vitamin D is mainly produced by exposure to sunlight, little is known regarding vitamin D levels in populations living in sub-Arctic areas with little or no daylight during winter.Objective. We describe distributions of vitamin D3 and the prevalence of adequate levels in a population living above 63°N.Design. We sampled 1,622 randomly selected subjects, aged 25–74 years, between January and May, 2009, as part of the Northern Sweden MONICA study (69.2% participation rat...

  1. Towards a sustainable architecture: Adequate to the environment and of maximum energy efficiency; Hacia una arquitectura sustentable: adecuada al ambiente y de maxima eficiencia energetica

    Morillon Galvez, David [Comision Nacional para el Ahorro de Energia, Mexico, D. F. (Mexico)

    1999-07-01

    An analysis of the elements and factors that the architecture of buildings must have to be sustainable, such as: a design adequate to the environment, saving and efficient use of alternate energies, and the auto-supply is presented. In addition a methodology for the natural air conditioning (bioclimatic architecture) of buildings, as well as ideas for the saving and efficient use of energy, with the objective of contributing to the adequate use of components of the building (walls, ceilings, floors etc.), is presented, that when interacting with the environment it takes advantage of it, without deterioration of the same, obtaining energy efficient designs. [Spanish] Se presenta un analisis de los elementos y factores que debe tener la arquitectura de edificios para ser sustentable, como; un diseno adecuado al ambiente, ahorro y uso eficiente de la energia, el uso de energias alternas y el autoabastecimiento. Ademas se propone una metodologia para la climatizacion natural (arquitectura bioclimatica) de edificios, asi como ideas para el ahorro y uso eficiente de energia, con el objetivo de aportar al uso adecuado de componentes del edificio (muros, techos, pisos etc.) que al interactuar con el ambiente tome ventaja de el, sin deterioro del mismo, logrando disenos energeticamente eficientes.

  2. Effects of the antituberculous drug ethambutol on zinc absorption, turnover and distribution in rats fed diet marginal and adequate in zinc

    King, A.B.; Schwartz, R.

    1987-04-01

    Ethambutol, (CH/sub 3/CH/sub 2/-CH(CH/sub 2/OH)-NH-CH/sub 2/)/sub 2/ (EMB), is an oral antituberculous agent that is administered therapeutically over extended time periods. It has chelating properties and may affect mineral metabolism. Male weanling Sprague-Dawley rats received 0, 400 or 600 mg EMB per kilogram body weight daily by gavage for 30 d. They were fed a casein-based diet with either adequate (49 ppm) or marginal (11 ppm) zinc. Both adequate-Zn (AZn) and marginal-Zn (MZn) rats receiving EMB showed alopecia and dose-dependent reductions in feed intake, weight gain and feed efficiency. None of these changes was seen in rats fed the MZn diet without EMB. Serum and tissue zinc levels were similar in rats not receiving EMB, regardless of the dietary zinc level. Serum zinc was consistently lower in AZn and MZn rats receiving EMB than in rats without EMB. Apparent zinc absorption, measured by /sup 65/Zn balance, was higher in AZn rats receiving EMB than in AZn rats without EMB. Thus, changes in absorption could not account for lower serum zinc levels in EMB-treated rats. However, /sup 65/Zn turnover was also higher in EMB groups. This suggests that EMB may have increased urinary zinc losses resulting in reduced circulating zinc and a consequent increase in zinc absorption.

  3. How Feasible is Adequate Yearly Progress (AYP? Simulations of School AYP "Uniform Averaging" and "Safe Harbor" under the No Child Left Behind Act

    Jaekyung Lee

    2004-04-01

    Full Text Available The No Child Left Behind Act of 2001 (NCLB requires that schools make “adequate yearly progress” (AYP towards the goal of having 100 percent of their students become proficient by year 2013-14. Through simulation analyses of Maine and Kentucky school performance data collected during the 1990s, this study investigates how feasible schools would have met the AYP targets if the mandate had been applied in the past with “uniform averaging (rolling averages” and “safe harbor” options that have potential to help reduce the number of schools needing improvement or corrective action. Contrary to some expectations, the applications of both options would do little to reduce the risk of massive school failure due to unreasonably high AYP targets for all student groups. Implications of the results for the NCLB school accountability system and possible ways to make the current AYP more feasible and fair are discussed.

  4. The content of African diets is adequate to achieve optimal efficacy with fixed-dose artemether-lumefantrine: a review of the evidence.

    Premji, Zulfiqarali G; Abdulla, Salim; Ogutu, Bernhards; Ndong, Alice; Falade, Catherine O; Sagara, Issaka; Mulure, Nathan; Nwaiwu, Obiyo; Kokwaro, Gilbert

    2008-01-01

    older populations, indicating that food consumption is adequate post-weaning. In conclusion, it appears that only a very small amount of dietary fat is necessary to ensure optimal efficacy with AL and that the fat content of standard meals or breast milk in sub-Saharan Africa is adequate. PMID:19032767

  5. The content of African diets is adequate to achieve optimal efficacy with fixed-dose artemether-lumefantrine: a review of the evidence

    Sagara Issaka

    2008-11-01

    rates to those observed in older populations, indicating that food consumption is adequate post-weaning. In conclusion, it appears that only a very small amount of dietary fat is necessary to ensure optimal efficacy with AL and that the fat content of standard meals or breast milk in sub-Saharan Africa is adequate.

  6. Estimation of adequate setup margins and threshold for position errors requiring immediate attention in head and neck cancer radiotherapy based on 2D image guidance

    We estimated sufficient setup margins for head-and-neck cancer (HNC) radiotherapy (RT) when 2D kV images are utilized for routine patient setup verification. As another goal we estimated a threshold for the displacements of the most important bony landmarks related to the target volumes requiring immediate attention. We analyzed 1491 orthogonal x-ray images utilized in RT treatment guidance for 80 HNC patients. We estimated overall setup errors and errors for four subregions to account for patient rotation and deformation: the vertebrae C1-2, C5-7, the occiput bone and the mandible. Setup margins were estimated for two 2D image guidance protocols: i) imaging at first three fractions and weekly thereafter and ii) daily imaging. Two 2D image matching principles were investigated: i) to the vertebrae in the middle of planning target volume (PTV) (MID-PTV) and ii) minimizing maximal position error for the four subregions (MIN-MAX). The threshold for the position errors was calculated with two previously unpublished methods based on the van Herk’s formula and clinical data by retaining a margin of 5 mm sufficient for each subregion. Sufficient setup margins to compensate the displacements of the subregions were approximately two times larger than were needed to compensate setup errors for rigid target. Adequate margins varied from 2.7 mm to 9.6 mm depending on the subregions related to the target, applied image guidance protocol and early correction of clinically important systematic 3D displacements of the subregions exceeding 4 mm. The MIN-MAX match resulted in smaller margins but caused an overall shift of 2.5 mm for the target center. Margins ≤ 5mm were sufficient with the MID-PTV match only through application of daily 2D imaging and the threshold of 4 mm to correct systematic displacement of a subregion. Adequate setup margins depend remarkably on the subregions related to the target volume. When the systematic 3D displacement of a subregion exceeds 4 mm, it

  7. Open of chat rooms for discussing geological disposal issues and review of adequate approaches for offering the information using the internet

    JNC is doing publicity work to let the technical reliability for geological disposal of high-level radioactive waste (HLW) comprehended widely. But the information about geological disposal of HLW itself and its technology has not been spread and recognized. It has been required to offer the opportunity to discuss the geological disposal and its technology as our own issue. Recently the internet, which has such characteristics as two-way, instant and open communication means, has become used on business and for pleasure commonly. So the opportunity for discussing the topics related to geological disposal of HLW has been offered on the internet web site so-called 'Internet Forum' by JNC since fiscal year 1999. 'Internet Forum' or an assembly of chat rooms is being run on the web server which is not operated by JNC in order to provide the place where discussion on the issue can be done as fairly and objectively as possible. In this report, the results of Internet Forum in fiscal year 2000 comparing with that in fiscal year 1999 were shown and the adequate approaches of operating 'Internet Forum' and offering the information about geological disposal of HLW were reviewed. (author)

  8. Axial 3D region of interest reconstruction using weighted cone beam BPF/DBPF algorithm cascaded with adequately oriented orthogonal butterfly filtering

    Tang, Shaojie; Tang, Xiangyang

    2016-03-01

    Axial cone beam (CB) computed tomography (CT) reconstruction is still the most desirable in clinical applications. As the potential candidates with analytic form for the task, the back projection-filtration (BPF) and the derivative backprojection filtered (DBPF) algorithms, in which Hilbert filtering is the common algorithmic feature, are originally derived for exact helical and axial reconstruction from CB and fan beam projection data, respectively. These two algorithms have been heuristically extended for axial CB reconstruction via adoption of virtual PI-line segments. Unfortunately, however, streak artifacts are induced along the Hilbert filtering direction, since these algorithms are no longer accurate on the virtual PI-line segments. We have proposed to cascade the extended BPF/DBPF algorithm with orthogonal butterfly filtering for image reconstruction (namely axial CB-BPP/DBPF cascaded with orthogonal butterfly filtering), in which the orientation-specific artifacts caused by post-BP Hilbert transform can be eliminated, at a possible expense of losing the BPF/DBPF's capability of dealing with projection data truncation. Our preliminary results have shown that this is not the case in practice. Hence, in this work, we carry out an algorithmic analysis and experimental study to investigate the performance of the axial CB-BPP/DBPF cascaded with adequately oriented orthogonal butterfly filtering for three-dimensional (3D) reconstruction in region of interest (ROI).

  9. Can Sophie's choice be adequately captured by cold computation of minimizing losses? An fMRI study of vital loss decisions.

    Qi Li

    Full Text Available The vast majority of decision-making research is performed under the assumption of the value maximizing principle. This principle implies that when making decisions, individuals try to optimize outcomes on the basis of cold mathematical equations. However, decisions are emotion-laden rather than cool and analytic when they tap into life-threatening considerations. Using functional magnetic resonance imaging (fMRI, this study investigated the neural mechanisms underlying vital loss decisions. Participants were asked to make a forced choice between two losses across three conditions: both losses are trivial (trivial-trivial, both losses are vital (vital-vital, or one loss is trivial and the other is vital (vital-trivial. Our results revealed that the amygdala was more active and correlated positively with self-reported negative emotion associated with choice during vital-vital loss decisions, when compared to trivial-trivial loss decisions. The rostral anterior cingulate cortex was also more active and correlated positively with self-reported difficulty of choice during vital-vital loss decisions. Compared to the activity observed during trivial-trivial loss decisions, the orbitofrontal cortex and ventral striatum were more active and correlated positively with self-reported positive emotion of choice during vital-trivial loss decisions. Our findings suggest that vital loss decisions involve emotions and cannot be adequately captured by cold computation of minimizing losses. This research will shed light on how people make vital loss decisions.

  10. Typhoid fever: hurdles to adequate hand washing for disease prevention among the population of a peri-urban informal settlement in Fiji

    Mosese Salusalu

    2013-01-01

    Full Text Available Problem/context: The Pacific island nation of Fiji Islands has high rates of endemic typhoid fever which is difficult to diagnose and often underreported. However, the majority of cases are preventable through use of safe water; adequate sanitation; vaccination; and, most sustainable of all, simple hygienic behaviour, such as hand washing with soap (HWWS. Despite many attempts by public health authorities, little progress has been made in the area of environmental adaptation and behaviour change. Action: To explore perceptions of typhoid fever risk among urban squatters and behavioural determinants surrounding HWWS, indigenous Fijians living in informal settlements with high typhoid fever incidence were invited to participate in focus group discussions. In-depth interviews were conducted with community leaders. Outcome: Perceptions of typhoid fever suggest confusion about risk factors, symptoms and communicability. Environmental barriers for hand washing were related to water and soap access. Standard social marketing approaches have been trialled with little clear evidence of impact. Despite this, we continue to advocate for the social and cultural determinants of typhoid prevention to remain central to future public health strategies. Discussion: Despite behaviour change being notoriously difficult, we argue that community-driven behaviour adaptation initiatives based on sound epidemiological evidence and health communication theory are likely to have significant impact and greater likelihood of sustainability.

  11. Confidence in the Knowledge Base of English Language Learners Studying Science: Using Agency to Compensate for the Lack of Adequate Linguistic Identity

    Hayes, Aneta L.; Mansour, Nasser

    2016-01-01

    Changes in the cultural and linguistic environments of learners are often associated with identity shifts. The aim of this study was to explore what identity shifts occur when science students from Bahraini national schools transition to an international university. The role of two aspects of learner identity—that is, English proficiency and science background knowledge, was examined in this study. Focus groups and semi-structured interviews were conducted with students and with university lecturers. The analysis suggested three conceptual themes of (1) reliance on science knowledge, (2) the auxiliary role of professional language and (3) adequacy of student learning strategies, demonstrating what subjective meanings the participants ascribe to the interplay between science knowledge and linguistic ability. The findings suggest that despite the lack of adequate linguistic attributes, the students are still able to successfully learn science in the context of language change. It is also implied that through strategically utilising their academic background in science, students preserve their identity as successful learners from school through to university. We conclude that agency plays a separate role in transition and is not a sole function of identity. We also contest the idea of language as a necessary attribute of one's identity as it was perceived by our participants to be an advantage and an auxiliary tool rather than a requirement.

  12. Bedside Calculation of Energy Expenditure Does Not Guarantee Adequate Caloric Prescription in Long-Term Mechanically Ventilated Critically Ill Patients: A Quality Control Study

    E. De Waele

    2012-01-01

    Full Text Available Nutrition is essential in critically ill patients, but translating caloric prescriptions into adequate caloric intake remains challenging. Caloric prescriptions (P, effective intake (I, and caloric needs (N, calculated with modified Harris-Benedict formulas, were recorded during seven consecutive days in ventilated patients. Adequacy of prescription was estimated by P/N ratio. I/P ratio assessed accuracy of translating a prescription into administered feeding. I/N ratio compared delivered calories with theoretical caloric needs. Fifty patients were prospectively studied in a mixed medicosurgical ICU in a teaching hospital. Basal and total energy expenditure were, respectively, 1361±171 kcal/d and 1649±233 kcal/d. P and I attained 1536±602 kcal/d and 1424±572 kcal/d, respectively. 24.6% prescriptions were accurate, and 24.3% calories were correctly administered. Excessive calories were prescribed in 35.4% of patients, 27.4% being overfed. Caloric needs were underestimated in 40% prescriptions, with 48.3% patients underfed. Calculating caloric requirements by a modified standard formula covered energy needs in only 25% of long-term mechanically ventilated patients, leaving many over- or underfed. Nutritional imbalance mainly resulted from incorrect prescription. Failure of “simple” calculations to direct caloric prescription in these patients suggests systematic use of more reliable methods, for example, indirect calorimetry.

  13. Are Lateral Electronic Portal Images Adequate for Accurate On-Line Daily Targeting of the Prostate? Results of a Prospective Study

    The purpose of this report was to evaluate the magnitude of the error that would be introduced if only a lateral (LAT) portal image, as opposed to a pair of orthogonal images, was used to verify and correct daily setup errors and organ motion in external beam radiation therapy (EBRT) of prostate cancer. The 3-dimensional (3D) coordinates of gold markers from 12 consecutive prostate patients were reconstructed using a pair of orthogonal images. The data were re-analyzed using only the LAT images. Couch moves from the 2-dimensional (2D)-only data were compared with the complete 3D data set. The 2D-only data provided couch moves that differed on average from the 3D data by 2.3 ± 3.0, 0.0 ± 0.0, and 0.8 ± 1.0 mm in the Lat, AP, and SI directions, respectively. Along AP and SI axes, the LAT image provided positional information similar to the orthogonal pair. The error along the LAT axis may be acceptable provided lateral margins are large enough. A LAT-only setup protocol reduces patient treatment times and increases patient throughput. In most circumstances, with exceptions such as morbidly obese patients, acquisition of only a LAT image for daily targeting of the prostate will provide adequate positional precision

  14. Open of chat rooms for discussing geological disposal issues and review of adequate approaches for offering the information using the internet

    Takizawa, Masayuki; Ito, Toshikazu; Yabuta, Naohiro; Yoshizawa, Nobuaki; Tsunoda, Hirokazu [Mitsubishi Research Inst., Inc., Tokyo (Japan)

    2001-03-01

    JNC is doing publicity work to let the technical reliability for geological disposal of high-level radioactive waste (HLW) comprehended widely. But the information about geological disposal of HLW itself and its technology has not been spread and recognized. It has been required to offer the opportunity to discuss the geological disposal and its technology as our own issue. Recently the internet, which has such characteristics as two-way, instant and open communication means, has become used on business and for pleasure commonly. So the opportunity for discussing the topics related to geological disposal of HLW has been offered on the internet web site so-called 'Internet Forum' by JNC since fiscal year 1999. 'Internet Forum' or an assembly of chat rooms is being run on the web server which is not operated by JNC in order to provide the place where discussion on the issue can be done as fairly and objectively as possible. In this report, the results of Internet Forum in fiscal year 2000 comparing with that in fiscal year 1999 were shown and the adequate approaches of operating 'Internet Forum' and offering the information about geological disposal of HLW were reviewed. (author)

  15. Direito humano à alimentação adequada: um olhar urbano The human right to adequate food: an urban vision

    Juliana Pereira Casemiro

    2010-07-01

    Full Text Available O direito humano à alimentação adequada é compreendido em duas dimensões: estar livre da fome e da desnutrição e ter acesso a uma alimentação adequada1,2. No contexto urbano, com seu forte apelo ao consumo e em que a aquisição de alimentos se dá prioritariamente a partir de relações mercantis, debater este tema em bairros empobrecidos apresenta-se como grande desafio. Este artigo reúne reflexões realizadas a partir de um estudo qualitativo realizado em São João de Meriti, município localizado na Baixada Fluminense (RJ, reunindo líderes da Pastoral da Criança em sessões de grupo focal. O desemprego e subemprego e a dificuldade de acesso aos serviços públicos de saúde, assistência social e saneamento foram apresentados como principais obstáculos para a efetivação do direito humano à alimentação. Foi possível identificar que, dentre as estratégias de enfrentamento da pobreza e da fome, o estabelecimento de circuitos de ajuda mútua tem grande destaque. Apoio social, dádiva e religiosidade apresentaram-se como categorias relevantes nas reflexões dos líderes. Diante de uma realidade em que a pobreza e a fome ou são naturalizadas ou se revertem em moeda de troca durante as eleições, a questão do clientelismo aparece como grande preocupação e desafio para estes líderes.The human right to adequate food is comprehended in two dimensions: being free of hunger and denutrition and having access to an adequate food. The urban context, in which the possession of food is done primarily through merchandising because of its strong consuming appealing, became a big challenge to debate this topic in poor districts today. Here we combine considerations of a qualitative study carried out in São João de Meriti, Rio de Janeiro State, joining leaders from Pastoral da Criança in focal group sessions. The unemployment, the sub-employment and the difficulty in reaching the public health system, the social assistance and basic

  16. Evaluation of a diet quality index based on the probability of adequate nutrient intake (PANDiet using national French and US dietary surveys.

    Eric O Verger

    Full Text Available BACKGROUND: Existing diet quality indices often show theoretical and methodological limitations, especially with regard to validation. OBJECTIVE: To develop a diet quality index based on the probability of adequate nutrient intake (PANDiet and evaluate its validity using data from French and US populations. MATERIAL AND METHODS: The PANDiet is composed of adequacy probabilities for 24 nutrients grouped into two sub-scores. The relationship between the PANDiet score and energy intake were investigated. We evaluated the construct validity of the index by comparing scores for population sub-groups with 'a priori' differences in diet quality, according to smoking status, energy density, food intakes, plasma folate and carotenoid concentrations. French and US implementations of the PANDiet were developed and evaluated using national nutritional recommendations and dietary surveys. RESULTS: The PANDiet was not correlated with energy for the French implementation (r = -0.02, P>0.05 and correlated at a low level for the US implementation (r = -0.11, P<0.0001. In both implementations, a higher PANDiet score (i.e. a better diet quality was associated with not smoking, having a lower-energy-dense diet, consuming higher amounts of fruits, vegetables, fish, milk and other dairy products and lower amounts of cheese, pizza, eggs, meat and processed meat, and having higher plasma folate and carotenoid concentrations after controlling for appropriate factors (all P<0.05, carotenoid data for US not available. CONCLUSIONS: The PANDiet provides a single score that measures the adequacy of nutrient intake and reflects diet quality. This index is adaptable for use in different countries and relevant at the individual and population levels.

  17. Actions Needed to Ensure Scientific and Technical Information is Adequately Reviewed at Goddard Space Flight Center, Johnson Space Center, Langley Research Center, and Marshall Space Flight Center

    2008-01-01

    This audit was initiated in response to a hotline complaint regarding the review, approval, and release of scientific and technical information (STI) at Johnson Space Center. The complainant alleged that Johnson personnel conducting export control reviews of STI were not fully qualified to conduct those reviews and that the reviews often did not occur until after the STI had been publicly released. NASA guidance requires that STI, defined as the results of basic and applied scientific, technical, and related engineering research and development, undergo certain reviews prior to being released outside of NASA or to audiences that include foreign nationals. The process includes technical, national security, export control, copyright, and trade secret (e.g., proprietary data) reviews. The review process was designed to preclude the inappropriate dissemination of sensitive information while ensuring that NASA complies with a requirement of the National Aeronautics and Space Act of 1958 (the Space Act)1 to provide for the widest practicable and appropriate dissemination of information resulting from NASA research activities. We focused our audit on evaluating the STI review process: specifically, determining whether the roles and responsibilities for the review, approval, and release of STI were adequately defined and documented in NASA and Center-level guidance and whether that guidance was effectively implemented at Goddard Space Flight Center, Johnson Space Center, Langley Research Center, and Marshall Space Flight Center. Johnson was included in the review because it was the source of the initial complaint, and Goddard, Langley, and Marshall were included because those Centers consistently produce significant amounts of STI.

  18. Reference intervals of thyroid hormones in a previously iodine-deficient but presently more than adequate area of Western China: a population-based survey.

    Cai, Jing; Fang, Yujie; Jing, Da; Xu, Shaoyong; Ming, Jie; Gao, Bin; Shen, Han; Zhang, Rong; Ji, Qiuhe

    2016-04-25

    The aim of our study is to establish the reference intervals (RIs) of thyroid hormones in a previously iodine-deficient area but presently more than iodine-adequate area of Western China, and also to investigate the factors which affect thyroid function. The cross-sectional study conducted in Xi'an, was based on 2007-2008 China National Diabetes and Metabolic Disorders Survey. Among 1286 participating adults, 717 were finally included as reference population. Thyrotropin (TSH), total triiodothyronine (T3), free triiodothyronine (FT3), total thyroxine (T4), free thyroxine (FT4), thyroperoxidase antibody (TPO-Ab) and thyroglobulin antibody (Tg-Ab) were measured. Thyroid ultrasound examination was also performed. The present study established the new RIs of serum TSH (0.43-5.51 mIU/L), FT4 (11.0-20.4 pmol/L), FT3 (3.63-5.73 pmol/L), T4 (67.8-157 mmol/L) and T3 (1.08-2.20 mmol/L), which were different from the data provided by the manufacturers. Significant differences among all the age groups were observed in FT3, but neither in TSH nor in FT4. The TSH levels in adults with pathologic ultrasonography results or positive thyroid autoantibody were significantly higher than those in reference adults. Our present results provide valuable references for the diagnosis of thyroid diseases in population of Western China. Considering that most inland areas of China have faced the challenge of the transition from iodine deficiency to adequacy or more than adequacy, we recommend physicians utilize our RIs to determine thyroid diseases in the similar areas with Xi'an in China. PMID:26842591

  19. Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU per day on biochemical responses and the wellbeing of patients

    Hu Amanda

    2004-07-01

    Full Text Available Abstract Background For adults, vitamin D intake of 100 mcg (4000 IU/day is physiologic and safe. The adequate intake (AI for older adults is 15 mcg (600 IU/day, but there has been no report focusing on use of this dose. Methods We compared effects of these doses on biochemical responses and sense of wellbeing in a blinded, randomized trial. In Study 1, 64 outpatients (recruited if summer 2001 25(OHD Results In Study 1, basal summer 25-hydroxyvitamin D [25(OHD] averaged 48 ± 9 (SD nmol/L. Supplementation for more than 6 months produced mean 25(OHD levels of 79 ± 30 nmol/L for the 15 mcg/day group, and 112 ± 41 nmol/L for the 100 mcg/day group. Both doses lowered plasma parathyroid hormone with no effect on plasma calcium. Between December and February, wellbeing score improved more for the 100-mcg/day group than for the lower-dosed group (1-tail Mann-Whitney p = 0.036. In Study 2, 25(OHD averaged 39 ± 9 nmol/L, and winter wellbeing scores improved with both doses of vitamin D (two-tail p Conclusion The highest AI for vitamin D brought summertime 25(OHD to >40 nmol/L, lowered PTH, and its use was associated with improved wellbeing. The 100 mcg/day dose produced greater responses. Since it was ethically necessary to provide a meaningful dose of vitamin D to these insufficient patients, we cannot rule out a placebo wellbeing response, particularly for those on the lower dose. This work confirms the safety and efficacy of both 15 and 100 mcg/day vitamin D3 in patients who needed additional vitamin D.

  20. Muscle protein turnover in rats treated with corticosterone (CC) or/and nandrolone decanoate (ND) and fed an adequate or a low-protein diet

    Santidrian, S.; Cuevillas, F.; Goena, M.; Larralde, J.

    1986-03-01

    In order to investigate the possible antagonistic effect between glucocorticoids and androgens on muscle protein turnover, the authors have measured the fractional rates of gastrocnemius muscle protein synthesis (k/sub s/) and degradation (k/sub d/) by the constant-intravenous-infusion method using L-//sup 14/C/-tyrosine in rats receiving via s.c. per 100 g b.wt. 10 mg of CC, or 2 mg of ND or CC+ND at the indicated doses, and fed either an 18% or 5% protein diets over a period of 5 days. As an additional index of protein synthesis, RNA activity (g of synthesized protein/day/g RNA) was determined as well. Results showed that as compared to vehicle-injected animals fed the adequate diet, CC-treated rats exhibited a reduction of muscle k/sub d/, while ND-treated rats had an outstanding increase of muscle k/sub s/. However, rats receiving CC+ND showed k/sub s/ and k/sub d/ values similar to those displayed by control animals. Nevertheless, when the steroids were injected to rats fed the low-protein diet, CC has a catabolic effect on muscle protein but by reducing k/sub s/, while the anabolic action of ND is still displayed but by a significant reduction of muscle k/sub d/. CC+ND given to these protein-deficient rats caused an increase in muscle k/sub s/ and a reduction in k/sub d/. These results might indicate that, at least in part, ND antagonizes the catabolic action of high doses of CC on muscle protein metabolism.

  1. [The influence of dietary fibers on cell immunity under the adequate nutrition and in the presence of alimentary polyhypovitaminosis in rats].

    Trushina, É N; Mustafina, O K; Vrzhesinskaia, O A

    2013-01-01

    The effect of wheat bran on cell immunity in rats adequately provided with vitamins or insufficiently supplied with vitamins has been investigated. 48 male Wistar rats (58.1 +/- 0.5 g) were divided into 6 group and fed with complete semi-synthetic diet, containing 100% or 20% of vitamin mixture (Vit) with or without supplement of insoluble dietary fiber (DF) in the dose corresponding to the upper allowable level of its consumption (5% wheat bran of diet mass) for 4 weeks. The animals of the 1 group received 100% of vitamin mixture (100% Vit); 2 group--100% Vit+DF; 3 group--20% of vitamin mixture (20% Vit); 4 group--20% of vitamin mixture and DF (20% Vit+DF). The next 5 days rats from vitamin-deficient groups were fed with diets supplemented with 80% of Vit: (5 group--20% Vit+80% Vit; 6 group--20% Vit+DF+80% Vit). The contents of lymphocytes, relative quantity of B-(CD45RA+) and T-lymphocytes (CD3+), subpopulations of T-lymphocytes: T-helper (CD3+CD4+) and cytotoxic T-lymphocytes (CD3+CD8+), NK-cells (CD161a+) in the peripheral blood of rats were determined by the method of flow cytometry using Beckman Coulter FC 500 (USA) cytometer. In rats fed complete semi-synthetic diet supplemented with DF (100% Vit+DF) the reduction of relative contents of T-lymphocytes and the increase of the fraction of cytotoxic T-lymphocytes in peripheral blood has been found. The analogous changes and more pronounced degree of immunosupression, that appeared in a lymphocytopenia, much smaller level of T-lymphocytes, T-helper and increase of cytotoxic T-lymphocytes content in rats fed a low vitamins diet (20% Vit) in comparison with these parameters of control group, have been detected. In rats received 20% Vit+DF the suppressed cell immunity was accompanied with decreased level of NK-cells. Normalization of vitamins content in the diets of rat deficient groups led to an almost complete recovery of cell immunity indicators to the level of the animals from the corresponding control groups

  2. Combined photon-electron beams in the treatment of the supraclavicular lymph nodes in breast cancer: A novel technique that achieves adequate coverage while reducing lung dose

    Salem, Ahmed, E-mail: ahmed.salem@doctors.org.uk [Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Mohamad, Issa; Dayyat, Abdulmajeed [Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Kanaa’n, Haitham [Section of Medical Physics, Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Sarhan, Nasim [Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Roujob, Ibrahim [Section of Medical Physics, Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Salem, Abdel-Fattah [Department of Obstetrics and Gynecology, Hashemite University, Zarqa (Jordan); Afifi, Shatha [Section of Medical Physics, Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan); Jaradat, Imad; Mubiden, Rasmi; Almousa, Abdelateif [Department of Radiation Oncology, King Hussein Cancer Center, Amman (Jordan)

    2015-10-01

    -only plans (mean = 16.2 ± 3%, p < 0.001). As expected, photon-only plans demonstrated the highest target coverage and total lung V{sub 20} {sub Gy}. The superiority of electron-only beams, in terms of decreasing lung dose, is set back by the dosimetric hotspots associated with such plans. Combined photon-electron treatment is a feasible technique for supraclavicular nodal irradiation and results in adequate target coverage, acceptable dosimetric hotspot volume, and slightly reduced lung dose.

  3. Combined photon-electron beams in the treatment of the supraclavicular lymph nodes in breast cancer: A novel technique that achieves adequate coverage while reducing lung dose

    -only plans demonstrated the highest target coverage and total lung V20 Gy. The superiority of electron-only beams, in terms of decreasing lung dose, is set back by the dosimetric hotspots associated with such plans. Combined photon-electron treatment is a feasible technique for supraclavicular nodal irradiation and results in adequate target coverage, acceptable dosimetric hotspot volume, and slightly reduced lung dose

  4. 專利侵害責任範圍因果關係的合理詮釋與再建構 Adequate Interpretation and

    沈宗倫 Chung-Lun Shen

    2011-06-01

    property damage. If no adequate causation is taken to measure the scope of patent damage, the damage would either overcompensate or frustrate the patentee. In view of the key role the causation is playing in adjusting patent damage, this article attempts to clarify and comment on the evaluation of patent damage under Taiwan patent law and related court cases, through the comparative observation of laws and the recognition of jurisprudence of patent law.

  5. Suggestions for an adequate risk communication - experiences based on German epidemiological studies on childhood cancer and neighbourhood to nuclear power plants; Empfehlungen fuer eine gute Risikokommunikation - Erfahrungen anhand deutscher Studien zu Krebs bei Kindern und Wohnortnaehe zu Kernkraftwerken

    Kaatsch, P. [Deutsches Kinderkrebsregister, Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik (IMBEI), Mainz (Germany)

    2006-07-01

    From the example of the German studies on childhood cancer in the vicinity of nuclear power plants general principles for adequate risk communication could be derived. It is particularly important to explain the complexity of the issue to the public in an adequate way, when dealing with topics of such an emotionally loaded nature. Some rules are required, when explaining the nature of risk to the layman, the press, politicians, or scientists from other fields. The main principle is to create a basis of trustfulness, whereupon results can be presented. In this contribution we derive general and proven specific recommendations for adequate risk communication on the basis of experiences made at the German Childhood Cancer Registry. (orig.)

  6. In vitro incorporation of selenium into tRNAs of Salmonella typhimurium

    Broken-cell preparations of Salmonella typhimurium rapidly incorporated 75Se from 75SeO3(2-) into tRNA by an ATP-dependent process. Selenium incorporation in the presence of 50 microM 75SeO3(2-) (0.8-1 pmol per A260 unit) was enhanced by the selenocysteine precursor, O-acetyl-L-serine (to 3.7 pmol per A260 unit). This increase in incorporation was a function of O-acetyl-L-serine concentration. Neither O-acetyl-L-homoserine nor O-phospho-L-serine stimulated the incorporation of selenium into tRNA. The incorporation of 75Se from 75SeO3(2-) was decreased by adding L-selenocysteine but not by adding the D isomer. When homologous bulk tRNA was added to the broken-cell preparations, an increased rate of 75Se labeling was observed. The supernatant fraction of the broken-cell preparation contained all of the enzymes required for this process. Reversed-phase HPLC analysis of labeled bulk tRNA digested to nucleosides showed the presence of a labeled compound that coeluted with authentic 5-methylaminomethyl-2-selenouridine

  7. Do immigrants from Turkey, Pakistan and Yugoslavia receive adequate medical treatment with beta-blockers and statins after acute myocardial infarction compared with Danish-born residents? A register-based follow-up study

    Hempler, Nana Folmann; Diderichsen, Finn; Larsen, Finn Breinholt;

    2010-01-01

    We undertook a study investigating whether immigrants from Turkey, Pakistan and Yugoslavia received adequate medical treatment with beta-blockers and statins after acute myocardial infarction (AMI) when compared with Danish-born residents and explored whether associations between patient origin and...

  8. An Adequate First Order Logic of Intervals

    Chaochen, Zhou; Hansen, Michael Reichhardt

    This paper introduces left and right neighbourhoods as primitive interval modalities to define other unary and binary modalities of intervals in a first order logic with interval length. A complete first order logic for the neighbourhood modalities is presented. It is demonstrated how the logic can...... support formal specification and verification of liveness and fairness, and also of various notions of real analysis....

  9. Exhibitors: Full of Confidence Adequate Preparation

    2009-01-01

    From March 26th,three most important trade fairs for Chinese textile industry opened successively inBeijing.Several exhibitors showed their confidence and preparation to TA Weekly. Bosideng:CHIC is an everlasting marketing chance"We’ll definitely participate in CHIC 2009,with even moreinvestment."Gao Dekang,the President of Bosideng Co.,Ltd said,"Bosideng is going to make full use of this trade fair for furtherdevelopment."According to the organizer of CHIC 2009,Bosidengreserved 1000 square meters for its show."CHIC witnessed the blooming development of Chinese clothingindustry for the last ten years.CHIC has made a progress to catch upwith the world trend as well as in the social influence.It has becomethe pioneer of fashion and is regarded as the releasing center,innovation center and brand center."As a long-term participant,Bosideng has the right to say these words.It is in this fair,Bosideng

  10. Undergraduate orthopedic education: Is it adequate?

    Menon Jagdish

    2009-01-01

    Full Text Available Background : Basic musculoskeletal knowledge is essential to the practice of medicine. The purpose of this study was to assess the adequacy of musculoskeletal knowledge of medical students. Materials and Methods : The validated basic competency examination in musculoskeletal medicine devised by Freidman and Bernstein was administered to final year medical students just prior to their final professional examination. Participants were also required to assess their confidence at making a musculoskeletal physical examination and diagnosis as well as comment on the adequacy of time in the curriculum devoted to Orthopedics. Results : The response rate was 83% (40/48. The average cognitive examination score was 48.3%. Two participants (5% obtained a score of ≥ 73.1%, the recommended mean passing score. Seventeen students (42.5% felt orthopedic clinical cases were the most difficult to perform a physical examination and diagnose. Thirteen students (32.5% felt that the time devoted to orthopedics in the medical curriculum was inadequate. Conclusions : Ninety-five percent of the students failed to show basic musculoskeletal competency. A change in medical curriculum and teaching methods is required to address this problem.

  11. Are shear force methods adequately reported?

    Holman, Benjamin W B; Fowler, Stephanie M; Hopkins, David L

    2016-09-01

    This study aimed to determine the detail to which shear force (SF) protocols and methods have been reported in the scientific literature between 2009 and 2015. Articles (n=734) published in peer-reviewed animal and food science journals and limited to only those testing the SF of unprocessed and non-fabricated mammal meats were evaluated. It was found that most of these SF articles originated in Europe (35.3%), investigated bovine species (49.0%), measured m. longissimus samples (55.2%), used tenderometers manufactured by Instron (31.2%), and equipped with Warner-Bratzler blades (68.8%). SF samples were also predominantly thawed prior to cooking (37.1%) and cooked sous vide, using a water bath (50.5%). Information pertaining to blade crosshead speed (47.5%), recorded SF resistance (56.7%), muscle fibre orientation when tested (49.2%), sub-section or core dimension (21.8%), end-point temperature (29.3%), and other factors contributing to SF variation were often omitted. This base failure diminishes repeatability and accurate SF interpretation, and must therefore be rectified. PMID:27107727

  12. Persistence of goiter despite adequate iodine intake

    To evaluate the state of iodine uptake and frequency of goiter in a previously endemic population after use of iodine salt for ten years. In an area in south of Iran following examination of randomly selected 1504, 8-10 year school children, 102 cases with grade 2 or larger goiter were found. One hundred normal cases regarding thyroid examination were also selected as controls. From all 202 children, random urine specimen was assayed for iodine as an indicator of iodide intake. Frequency of goiter grade 2 or larger was 6.8%. Median levels of urinary iodine in goiterous children and controls were 20.00 micro gram/dL and 24.50 micro gram/dL respectively. Values more than 10 micro g/dL indicate sufficient intake. Frequency of iodine deficiency in patients with goiter was 14.0% vs. 12.7% in control group. There was no statistically significant difference between the two groups (P value=0.748). Iodized salt has been effective to provide acceptable iodide intake but other causes are supposed to be responsible as etiologic factors for persistence of endemic goiter. (author)

  13. Internet privacy options for adequate realisation

    2013-01-01

    A thorough multidisciplinary analysis of various perspectives on internet privacy was published as the first volume of a study, revealing the results of the achatech project "Internet Privacy - A Culture of Privacy and Trust on the Internet." The second publication from this project presents integrated, interdisciplinary options for improving privacy on the Internet utilising a normative, value-oriented approach. The ways in which privacy promotes and preconditions fundamental societal values and how privacy violations endanger the flourishing of said values are exemplified. The conditions which must be fulfilled in order to achieve a culture of privacy and trust on the internet are illuminated. This volume presents options for policy-makers, educators, businesses and technology experts how to facilitate solutions for more privacy on the Internet and identifies further research requirements in this area.

  14. Chevron forecasts adequate energy through 2000

    Highlights of Chevron's 1986 forecast for the non-Communist countries are as follows, with 1985 forecasts shown in parenthesis. (1) Total energy consumption will grow at an average annual rate of 2.1% per year (versus 2.2% in last year's forecast). This rate is approximately two-thirds of the GNP rate of 3% per year. (2) Total oil consumption will grow at 1% per year, slightly less than one-half the rate for total energy (the same rate as in the 1985 forecast). (3) Oil production capability will exceed demand with OPEC share rising from 40% of total supply in 1985 to 55% in 2000. (4) Crude oil prices are expected to stabilize in 1987 in the $20 to $25 per barrel range. Prices are then expected to remain at this level until the 1990s when increased demand will place upward pressure on prices. Chevron expects prices in the $28 to $35 per barrel range by 2000. (5) Natural gas consumption will grow at an average rate of 2.2% per year. Prices paid by end-users are expected to be competitive with fuel oil by 1990. (6) Coal consumption will grow at 3.0% per year (3.2% per year growth was forecast in 1985) with prices rising with inflation. (7) Nuclear power will grow at a 4.5% annual rate mostly in Europe and Asia (the 1985 forecast called for 5.6% annual growth). (8) Synthetic liquids are not expected to contribute a significant volume by 2000 (in 1985 Chevron estimated 1 million barrels per year would be produced by 2000). Oil prices and energy supplies are discussed. The economic growth and energy demand for individual countries are forecast

  15. Adequate Rhetorical Delivery when Staging Premodernity

    Hansen, Jette Barnholdt

    2015-01-01

    Artiklen handler om iscenesættelse af performative kunstværker fra det 18. årh., der ofte også rummer stillingtagen til retorisk fremførelse. Jeg advokerer for, at man sammentænker synkrone indfaldsvinker med diakrone, så man fx ikke udelukkende fokuserer på at genskabe gestus fra det 18.århundre...

  16. Adipose Tissue - Adequate, Accessible Regenerative Material

    Kolaparthy, Lakshmi Kanth.; Sanivarapu, Sahitya; Moogla, Srinivas; Kutcham, Rupa Sruthi

    2015-01-01

    The potential use of stem cell based therapies for the repair and regeneration of various tissues offers a paradigm shift that may provide alternative therapeutic solutions for a number of diseases. The use of either embryonic stem cells (ESCs) or induced pluripotent stem cells in clinical situations is limited due to cell regulations and to technical and ethical considerations involved in genetic manipulation of human ESCs, even though these cells are highly beneficial. Mesenchymal stem cell...

  17. Adipose Tissue - Adequate, Accessible Regenerative Material.

    Kolaparthy, Lakshmi Kanth; Sanivarapu, Sahitya; Moogla, Srinivas; Kutcham, Rupa Sruthi

    2015-11-01

    The potential use of stem cell based therapies for the repair and regeneration of various tissues offers a paradigm shift that may provide alternative therapeutic solutions for a number of diseases. The use of either embryonic stem cells (ESCs) or induced pluripotent stem cells in clinical situations is limited due to cell regulations and to technical and ethical considerations involved in genetic manipulation of human ESCs, even though these cells are highly beneficial. Mesenchymal stem cells seen to be an ideal population of stem cells in particular, Adipose derived stem cells (ASCs) which can be obtained in large number and easily harvested from adipose tissue. It is ubiquitously available and has several advantages compared to other sources as easily accessible in large quantities with minimal invasive harvesting procedure, and isolation of adipose derived mesenchymal stem cells yield a high amount of stem cells which is essential for stem cell based therapies and tissue engineering. Recently, periodontal tissue regeneration using ASCs has been examined in some animal models. This method has potential in the regeneration of functional periodontal tissues because various secreted growth factors from ASCs might not only promote the regeneration of periodontal tissues but also encourage neovascularization of the damaged tissues. This review summarizes the sources, isolation and characteristics of adipose derived stem cells and its potential role in periodontal regeneration is discussed. PMID:26634060

  18. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India.

    James P Wirth

    Full Text Available Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0-35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana's rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana's anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana's public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana.

  19. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India.

    Wirth, James P; Leyvraz, Magali; Sodani, Prahlad R; Aaron, Grant J; Sharma, Narottam D; Woodruff, Bradley A

    2016-01-01

    Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0-35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana's rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana's anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana's public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana. PMID:27447925

  20. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India

    Wirth, James P.; Leyvraz, Magali; Sodani, Prahlad R.; Aaron, Grant J.; Sharma, Narottam D.; Woodruff, Bradley A.

    2016-01-01

    Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0–35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana’s rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana’s anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana’s public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana. PMID:27447925

  1. Identification of a selenocysteyl-tRNA(Ser) in mammalian cells that recognizes the nonsense codon, UGA

    The presence of a unique opal suppressor seryl-tRNA in higher vertebrates which is converted to phosphoseryl-tRNA has been known for several years, but its function has been uncertain. In the present study, we demonstrate that this tRNA species also occurs in vivo as selenocysteyl-tRNA(Ser) suggesting that it functions both as a carrier molecule upon which selenocysteine is synthesized and as a direct selenocysteine donor to a growing polypeptide chain in response to specific UGA codons. [75Se]Seleno[3H]cysteyl-tRNA(Ser) formed by administering 75Se and [3H]serine to rat mammary tumor cells (TMT-081-MS) in culture was isolated from the cell extract. The amino acid attached to the tRNA was identified as selenocysteine following its deacylation and reaction with iodoacetate and 3-bromopropionate. The resulting alkyl derivatives co-chromatographed on an amino acid analyzer with authentic carboxymethylselenocysteine and carboxyethylselenocysteine. Seryl-tRNA(Ser) and phosphoseryl-tRNA(Ser), which co-migrate on a reverse phase chromatographic column with selenocysteyl-tRNA(Ser), were also identified in extracts of TMT-018-MS cells. Hence, we propose that a metabolic pathway for selenocysteine synthesis in mammalian cells is the conversion of seryl-tRNA(Ser) via phosphoseryl-tRNA(Ser) to selenocysteyl-tRNA(Ser). In a ribosomal binding assay selenocysteyl-tRNA(Ser) recognizes UGA but not any of the serine codons. Selenocysteyl-tRNA(Ser) is deacylated more readily than seryl-tRNA(Ser) (i.e. 58% deacylation during 15 min at pH 8.0 and 37 degrees C as compared to 41%)

  2. THE EFFECTS OF SELENOCYSTEINE SE-METHYLTRANSFERASE ON SELENIUM METABOLISM IN TRANSGENIC BROCCOLI

    Selenium (Se) plays an indispensable role in human nutrition and has been implicated to have important health benefits, including being a cancer preventative agent. Se-methylselenocysteine, a monomethylated form of Se, has been shown to be one of the most effective chemopreventative compounds. Bro...

  3. The effects of Selenocysteine Se-Methyltransferase on Selenium metabolism in Broccoli

    Selenium (Se) plays an indispensable role in human nutrition and has suggested to have important health benefits, including as a cancer preventative agent. Se-methylselenocysteine, a monomethylated form of Se, has been shown to be one of the most effective chemopreventative compounds. Broccoli is ...

  4. Functions and cellular localization of cysteine desulfurase and selenocysteine lyase in Trypanosoma brucei

    Poliak, Pavel; Van Hoewyk, D.; Oborník, Miroslav; Zíková, Alena; Stuart, K. D.; Tachezy, J.; Pilon, M.; Lukeš, Julius

    2010-01-01

    Roč. 277, č. 2 (2010), s. 383-393. ISSN 1742-464X R&D Projects: GA ČR GA204/09/1667 Institutional research plan: CEZ:AV0Z60220518 Keywords : Fe–S cluster * mitochondrion * RNAi * selenoprotein * Trypanosoma Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.129, year: 2010

  5. Association of selenocysteine transfer RNA fragments with serum antibody response to Mycoplasma spp. in beef cattle

    The objective was to identify transfer RNA fragments (tRFs) associated with a serum antibody response to Mycoplasma spp. in beef cattle. Serum from sixteen beef calves was collected at three points: in summer after calves were born, in fall at weaning, and in the following spring. All sera collected...

  6. Estudo da adequabilidade de uma ferramenta de apoio ao ensino no Curso de Biblioteconomia da UDESC The adequateness study about face-to-face education support tools for Library Science Course - UDESC

    Fábio Lorensi do Canto

    2005-01-01

    Full Text Available [Resumo ] A presente pesquisa teve por objetivo avaliar a adequabilidade de uma ferramenta de apoio ao ensino (Polvo como suporte ao ensino presencial do curso de Biblioteconomia da UDESC. Para se chegar a um resultado que realmente expressasse o nível de comprometimento do corpo discente e docente com o uso do Polvo, identificou-se inicialmente o perfil dos usuários do sistema (alunos e professores e os benefícios/problemas obtidos com a utilização deste tipo de ferramenta. [Abstract ] This research was to evaluate the adequateness for face-to-face education support tool (Polvo to help the actual education of the Library Science from the UDESC. Describes some results between the Polvo´s use by students, staff and teachears, identified the users profile and benefit or problems gotten with this tool.

  7. Redox Signaling by the RNA Polymerase III TFIIB-Related Factor Brf2

    Gouge, Jerome; Satia, Karishma; Guthertz, Nicolas; Widya, Marcella; Thompson, Andrew James; Cousin, Pascal; Dergai, Oleksandr; Hernandez, Nouria; Vannini, Alessandro

    2015-01-01

    Summary TFIIB-related factor 2 (Brf2) is a member of the family of TFIIB-like core transcription factors. Brf2 recruits RNA polymerase (Pol) III to type III gene-external promoters, including the U6 spliceosomal RNA and selenocysteine tRNA genes. Found only in vertebrates, Brf2 has been linked to tumorigenesis but the underlying mechanisms remain elusive. We have solved crystal structures of a human Brf2-TBP complex bound to natural promoters, obtaining a detailed view of the molecular intera...

  8. Staf, a promiscuous activator for enhanced transcription by RNA polymerases II and III.

    Schaub, M; Myslinski, E; Schuster, C.; Krol, A.; Carbon, P

    1997-01-01

    Staf is a zinc finger protein that we recently identified as the transcriptional activator of the RNA polymerase III-transcribed selenocysteine tRNA gene. In this work we demonstrate that enhanced transcription of the majority of vertebrate snRNA and snRNA-type genes, transcribed by RNA polymerases II and III, also requires Staf. DNA binding assays and microinjection of mutant genes into Xenopus oocytes showed the presence of Staf-responsive elements in the genes for human U4C, U6, Y4 and 7SK...

  9. Quem são as crianças que se sentem gordas apesar de terem peso adequado? Who are the children with adequate weight who feel fat?

    Andréa Poyastro Pinheiro

    2006-06-01

    Full Text Available OBJETIVO: Investigar a prevalência de crianças com peso adequado que se sentem gordas e os fatores associados a essa percepção. METODOLOGIA: Estudo transversal com 901 escolares, entre 8 e 11 anos, selecionados por conglomerados. As crianças tiveram peso e altura aferidos e responderam um questionário com escala de auto-estima, autopercepção do peso e percepção da expectativa dos pais e amigos em relação a seu peso. RESULTADOS: A prevalência de escolares com percentil do índice de massa corporal (IMC OBJECTIVES: To measure the prevalence of children with adequate weight who feel fat and to examine the factors associated with this perception. METHODS: Cross-sectional study with 901 schoolchildren aged 8-11 years selected by cluster sampling. The children had their weight and height measured, and answered a questionnaire that included a self-esteem scale and questions on self-perception of weight, and perception of parents' and friends' expectations regarding the child's weight. RESULTS: The prevalence of children with BMI percentile < 85 who considered themselves fat was 13%, and the variables significantly associated with this perception were: female gender (OR = 2.45; 95%CI 1.42-4.24, 11 years of age (OR = 2.35; 95%CI 1.13-4.89, lowest quartile of self-esteem (OR = 2.08; 95%CI 1.17-3.68, the perception that parents expect them to be thinner (OR = 3.00; 95%IC 1.52-5.91, and body mass index percentile (OR = 1.04; 95%CI 1.03-1.06. CONCLUSION: The perception of being fat when having adequate weight afflicts children before preadolescence, particularly girls aged 11 years, with higher body mass index, lower self-esteem, and who think their parents expect them to be thinner. Future studies should examine in depth the causes and consequences of this attitude.

  10. Oral Calcidiol Is More Effective Than Cholecalciferol Supplementation to Reach Adequate 25(OH)D Levels in Patients with Autoimmune Diseases Chronically Treated with Low Doses of Glucocorticoids: A “Real-Life” Study

    Ortego-Jurado, Miguel; Callejas-Rubio, José-Luis; Ríos-Fernández, Raquel; González-Moreno, Juan; González Ramírez, Amanda Rocío; González-Gay, Miguel A.; Ortego-Centeno, Norberto

    2015-01-01

    Glucocorticoids (GCs) are the cornerstone of the therapy in many autoimmune and inflammatory diseases. However, it is well known that their use is a double edged sword, as their beneficial effects are associated almost universally with unwanted effects, as, for example glucocorticoid-induced osteoporosis (GIO). Over the last years, several clinical practice guidelines emphasize the need of preventing bone mass loss and reduce the incidence of fractures associated with GC use. Calcium and vitamin D supplementation, as adjunctive therapy, are included in all the practice guidelines. However, no standard vitamin D dose has been established. Several studies with postmenopausal women show that maintaining the levels above 30–33 ng/mL help improve the response to bisphosphonates. It is unknown if the response is the same in GIO, but in the clinical practice the levels are maintained at around the same values. In this study we demonstrate that patients with autoimmune diseases, undergoing glucocorticoid therapy, often present suboptimal 25(OH)D levels. Patients with higher body mass index and those receiving higher doses of glucocorticoids are at increased risk of having lower levels of 25(OH)D. In these patients, calcidiol supplementations are more effective than cholecalciferol to reach adequate 25(OH)D levels. PMID:26124976

  11. Twice single doses of 100,000 IU of vitamin D in winter is adequate and safe for prevention of vitamin D deficiency in healthy children from Ushuaia, Tierra Del Fuego, Argentina.

    Tau, Cristina; Ciriani, Viviana; Scaiola, Edit; Acuña, Martha

    2007-03-01

    In order to improve vitamin D status of children from Ushuaia (55 degrees S), at the South of Argentina, double supplementation with 100.000 IU of vitamin D was administered at the beginning of winter (March 2004), and 3 months later during winter (June 2004). In 2004, serum 25-hydroxyvitamin D (25OHD) was measured before the first supplementation, a month after, and 3 months after receiving the second supplementation (March, April and September). We studied 18 healthy children from Ushuaia, age (mean+/-S.D.) 7.3+/-4.4 years old (range 1.2-14.6), seven girls and 11 boys. Before treatment, serum 25OHD was 29.3+/-5.9 ng/ml. It increased significantly 1 month after the first supplementation (April): 35.3+/-4.4 ng/ml (p50 ng/ml). These results disclosed that to prevent vitamin D deficiency for children at zones of risk at the south of our country, double supplementation of 100,000 IU of vitamin D during autumn and winter, would be adequate and safe. PMID:17257830

  12. Adequate timing for heart-of-palm harvesting in King palm Determinação de estádio adequado para colheita de palmito de palmeira real australiana

    Marilene L.A. Bovi

    2001-07-01

    Full Text Available Heart-of-palm, palm heart, or "palmito" can be considered as a non-conventional vegetable, largely consumed in Brazil and exported to more than sixty countries. Timing of heart-of-palm harvesting is a critical issue in palmito agribusiness, since it affects yield, quality and costs. A three-year field experiment was utilized to identify the correct timing for king palm heart-of-palm harvesting, from the standpoint of maximizing yield and minimizing growing period. The experimental site was located at Pariqueraçu, Vale do Ribeira, a region where palmito agribusiness has increased recently, due to adequate climatic conditions, low costs and high industry demand. Crop was grown in 2 x 0.75 m spacing, utilizing six-month old seedlings. Growth was assessed periodically by measuring plant diameter and height (from soil level to insertion of leaf spear, as well as leaf number and size. Harvest was done, from 36 to 40 months after planting date. The results showed high plant variability, a common feature in palm. In spite of genetic variability, the adequate timing for start heart-of-palm harvesting (considering plant growth rate, yield, quality and market type, was reached when palms were 80 to 115 cm (small diameter and 200 to 300 cm tall (large diameter. The time to attain those heights varies widely among plants and growing conditions. In this experiment, harvesting could be started at 22 months after planting.Palmito é uma hortaliça não convencional, largamente consumida no Brasil e exportada para mais de sessenta países. A determinação do tempo adequado para sua colheita é fundamental para o agronegócio palmito, visto que afeta produção, qualidade e custos. Um experimento a campo, com três anos de idade, foi utilizado para identificar o ponto adequado de colheita de palmito da palmeira real australiana de forma a maximizar produção e minimizar tempo de cultivo. A área experimental está localizada em Pariqueraçu, Vale do Ribeira

  13. 中国农村职业人群健康素养现状及影响因素分析%Status and influencing factors of adequate health literacy among occupational populations in rural areas of China

    严丽萍; 魏南方; 安家璈; 王萍

    2012-01-01

    Objective To investigate the adequate health literacy (AHL) status and to analyze its influencing factors in rural occupational populations in China, and to provide scientific evidence for developing intervention strategies of health literacy. Methods The investigation covered 32 987 workers in rural areas aged 15-69 years selected from all provinces,autonomous regions,and municipalities of mainland China with multistage stratified random sampling method. A face-to-face questionnaire survey was conducted among the workers. Results The proportion of adequate health literacy (PAHL) among the rural workers was 3.98%. The proportion of the workers with AHL in mental,light physical labor, agriculture workers,and farmers was 16.90% , 16. 20% ,2. 14% , and 4. 50% respectively. The proportion of AHL for health concept and knowledge, lifestyle and behavior, and related skills among the workers was 10. 14% ,4. 09% ,and 13. 05% .respectively. In addition,the proportion of AHL was 23. 35% , 11. 35% ,2. 77% , 12. 33% ,and 4. 76% .respectively, for the following health issues: attitude towards health, safety and first aid, infectious diseases prevention, basic medical care,and chronic non-communicable diseases prevention, logistic regression analysis results indicated that education (odds ratio [ OR ] = 0.497 ), occupation ( OR = - 0.222), nationality (OR = -0.175), region ( OR = - 0. 167 -0. 071) ,age( OR = - 0. 094), and marriage (OR =0.049) were important influencing factors of AHL level in rural occupational populations. The educational level was positively correlated with the proportion of PAHL. PAHL was lower among elder people and the minority. The PAHL in the workers in central China was higher than that in the eastern China and PAHL was lowest in the workers of the Western. Conclusion Education, occupation, nationality, region, age, and marriage are important influence factors of health literacy and special intervention measures should be focused on these factors to

  14. Adequação dos índices da análise econômico-financeira às empresas florestais Adequateness of the economic and financial analysis in forestry companies

    Anselmo Chaves Neto

    2007-10-01

    ônimas de capital aberto, dentre as quais três empresas madeireiras e oito empresas produtoras de papel e celulose. Obteve-se, assim, uma matriz de dados de duzentas e trinta e sete linhas por vinte e seis colunas, sobre a qual aplicaram-se as técnicas estatísticas multivariadas, em particular a análise fatorial. A classificação das empresas, a partir dos escores fatoriais, possibilitou verificar quais índices são adequados à análise de quais tipos de empresas. O resultado mostrou que alguns destes vinte e seis índices não são adequados à análise daquelas onze empresas ligadas à área florestal.There are many methods for the economic and financial analysis of the companies. Among them, for many reasons, the most used one is the analyses through the index (MATARAZZO, 1998. Although a research in the specialized Brazilian bibliography enabled to identify more than two hundreds of different indexes. It’s selection by the usage criterion for the biggest number of authors reduced them into twenty-six indexes. From the specific operational features of forestry companies - his long operational cycle - it’s assumed that the usage of those indexes of generalized use in the economic and financial analysis of any company - whose operational cycle are relatively short - it isn’t adequate for the forestry companies analysis. Currently, there isn’t any references about specific indexes for the economic and financial analysis of forestry enterprises. It’s assumed that this difference between the operational cycles would result in economic and financial performance, as well as in totally diverse patrimonial conditions. There isn’t any reference about this pressupose either. Among others, one of the algorithms of big utility for the research is given by the factorial analysis, according JOHNSON & WICHERN (1998. According to the same authors, this technique let classify them by it’s participation in the totally variable data. Therefore, the main objective of

  15. Analysis of Strategy for Service Provider with Adequate Demand in Customer-Intensive Service%客源充足情境下的 customer-intensive 服务策略研究

    李武强; 刘树林

    2013-01-01

    In a wide variety of service industries , providing good service requires a high level of diligence and taking more time .Such service is called customer-intensive service .Usually , the value provided by such service increases with the time the service provider spends with the customer , but the waiting time would be longer at the same time.So, how can the service provider max revenue by setting service speed and price? As the queue theory is well known about describing the service process and congestion , the M/M/1 queuing model is intro-duced to analyse this problem for the monopolist with adequate demand when waiting cost is subdivided into time cost and anxiety cost .The paper shows that the revenue decreases as unit time cost and anxiety cost increase , but the reduction by unit anxiety cost is lower than unite fixed cost .Also, the strategy which suggests reducing anxiety cost by inputting certain service cost for waiting customers is proved available for the monopolist getting a higher revenue .%在customer-intensive服务中服务速度越慢,顾客的效用就越高,然而等待时间也随之变长;而服务商则需对服务速度和价格进行决策,以求获得最优收益。本文基于客源丰富的服务垄断商对此问题采用M/M/1排队模型进行了研究,将顾客成本细分为时间成本和焦虑成本,给出了最优服务速度和价格。研究发现,单位焦虑成本的增加造成了服务商收益的减少,但对收益的影响要小于单位时间成本。最后,提出了服务商投入一定的服务成本来减少焦虑成本的策略,以达到获取更高收益的目的,并证明了策略的有效性。

  16. Crystallization and preliminary X-ray crystallographic analysis of bacterial tRNASec in complex with seryl-tRNA synthetase

    Bacterial selenocysteine tRNA was crystallized as the heterologous complex with archaeal seryl-tRNA synthetase. X-ray diffraction was improved by introducing point mutations and heavy-atom labeling, and a 3.2 Å diffraction data set for phase determination was obtained from a platinum-labeled crystal. Selenocysteine (Sec) is translationally incorporated into proteins in response to the UGA codon. The tRNA specific to Sec (tRNASec) is first ligated with serine by seryl-tRNA synthetase (SerRS). To elucidate the tertiary structure of bacterial tRNASec and its specific interaction with SerRS, the bacterial tRNASec from Aquifex aeolicus was crystallized as the heterologous complex with the archaeal SerRS from Methanopyrus kandleri. Although X-ray diffraction by crystals of tRNASec in complex with wild-type SerRS was rather poor (to 5.7 Å resolution), the resolution was improved by introducing point mutations targeting the crystal-packing interface. Heavy-atom labelling also contributed to resolution improvement. A 3.2 Å resolution diffraction data set for phase determination was obtained from a K2Pt(CN)4-soaked crystal

  17. Quedas intra-hospitalares na Santa Casa de Belo Horizonte MG são adequadamente relatadas? Are In-hospital Falls at Santa Casa of Belo Horizonte- MG adequately reported?

    Joana Ude Viana

    2011-03-01

    Horizonte, the occurrence of in-hospital falls. The interview was accomplished with 37 professionals(doctors, interns and nurses through a semi-structured questionnaire which comprehended 11 questions related to the historical of falls in the sector, comprising information on the number of episodes, setting, time, patient age, activity performed at the moment, consequences, as well as questions regarding to environment adaptation. Data analysis conducted by means of descriptive statistics of the interviews showed that 65% of the employee reported the occurrence of falls. The majority (73% of fallers was men, with mean age of 78, 62 years (SD +- 7, 63 and fell more in the morning (31% and in the evening (31%, mainly in the room (48% and in the bathroom (42%, being 50% of the episodes non-injurious. We conclude that falls episodes occur in the hospital setting, but are not reported adequately, showing the need of adoption of educational measures to the professional who deal with this population.

  18. tRNA fragments: novel players in intergenerational inheritance.

    Gapp, Katharina; Miska, Eric A

    2016-04-01

    Non-genetic inheritance is an evocative topic; in the past few years, the debate around potential inheritance of life-time experiences independent of social factors in mammals has become highly prominent due to increasing evidence for phenotypes in the offspring after paternal environmental exposures. Strikingly, two independent studies published in Science newly implicate a special class of RNA, transfer RNA fragments, in the intergenerational effects of paternal dietary intervention. PMID:26902286

  19. Roles of tRNA in cell wall biosynthesis

    Dare, Kiley; Ibba, Michael

    2012-01-01

    Recent research into various aspects of bacterial metabolism such as cell wall and antibiotic synthesis, degradation pathways, cellular stress, and amino acid biosynthesis has elucidated roles of aminoacyl-transfer ribonucleic acid (aa-tRNA) outside of translation. Although the two enzyme families...... specificity of this diverse enzymatic family is necessary to aid current efforts in designing potential bactericidal agents. These two enzyme families are linked only by the substrate with which they modify the cell wall, aa-tRNA; their structure, cell wall modification processes and the physiological changes...... responsible for cell wall modifications, aminoacyl-phosphatidylglycerol synthases (aaPGSs) and Fem, were discovered some time ago, they have recently become of intense interest for their roles in the antimicrobial resistance of pathogenic microorganisms. The addition of positively charged amino acids to...

  20. The relationship between social capital, social support and the adequate use of prenatal care A relação entre capital social e suporte social com a adequação da utilização da atenção pré-natal

    Maria do Carmo Leal; Ana Paula Esteves Pereira; Gabriela de Almeida Lamarca; Mario Vianna Vettore

    2011-01-01

    This study investigated the relationship between social capital and social support and the adequate use of prenatal care. A follow-up study involving 1,485 pregnant women was conducted in two cities in the Rio de Janeiro State, Brazil. Demographic and socioeconomic characteristics, social support and social capital data were collected during the first trimester of pregnancy. The post-partum period included information on levels of prenatal care utilization, social networks, parity, obstetric ...

  1. Warm up practices of golfers: are they adequate?

    Fradkin, A; Finch, C; Sherman, C

    2001-01-01

    Background—Although it is widely recommended that golfers warm up before play or practice to enhance their physical performance and reduce their injury risk, it is not known to what extent they actually undertake such warm up procedures.

  2. Two coats of paint are not adequate on offshore installations

    When in the late 1990s paint manufacturers introduced their ''combination products'', they were confident that the pre-qualification tests had demonstrated that these products satisfied the Norsok requirements. It has been shown, however, that in some cases there is no direct relation between the good test results and the protection capability for offshore-exposed painted surfaces. The old maxim that several thin coats of paint offer better protection than a few thick ones are reflected by the fact that Statoil no longer accepts two-coat systems

  3. Identification of children with reading difficulties: Cheap can be adequate

    Poulsen, Mads; Nielsen, Anne-Mette Veber

    Classification of reading difficulties: Cheap screening can be accurate Purpose: Three factors are important for identification of students in need of remedial instruction: accuracy, timeliness, and cost. The identification has to be accurate to be of any use, the identification has to be timely......, inexpensive testing. The present study investigated the classification accuracy of three screening models varying in timeliness and cost. Method: We compared the ROC statistics of three logistic models for predicting end of Grade 2 reading difficulties in a sample of 164 students: 1) an early, comprehensive...... model using a battery of Grade 0 tests, including phoneme awareness, rapid naming, and paired associate learning, 2) a late, comprehensive model adding reading measures from January of Grade 1, and 3) a late, inexpensive model using only group-administered reading measures from January of Grade 1...

  4. Caring for an Ageing Population: Are Physiotherapy Graduates Adequately Prepared?

    Ramklass, Serela S.; Butau, Anne; Ntinga, Nomusa; Cele, Nozipho

    2010-01-01

    In view of South African policy developments related to the care of older persons, it was necessary to examine the nature of the geriatrics content within physiotherapy curricula. A survey was conducted amongst final-year student physiotherapists at South African universities, together with content analysis of physiotherapy curricula. Very little…

  5. Patients with Celiac Disease Are Not Followed Adequately

    Herman, Margot L.; Rubio-Tapia, Alberto; Lahr, Brian D.; Larson, Joseph J.; Van Dyke, Carol T.; Murray, Joseph A.

    2012-01-01

    Background & Aims Adherence to a gluten-free diet is the only effective treatment for celiac disease. It has been recommended that patients be followed, make regular visits to the clinic, and undergo serologic analysis for markers of celiac disease, although a follow-up procedure has not been standardized. We determined how many patients with celiac disease are actually followed. Methods We collected data on 122 patients with biopsy-proven celiac disease, diagnosed between 1996 and 2006 in Olmsted County, Minnesota (70% women, median age of 42 years) for whom complete medical records and verification of residency were available. We determined the frequency at which patients received follow-up examinations, from 6 months to 5 years after diagnosis. The Kaplan-Meier method was used to estimate event rates at 1 and 5 year(s). Patients were classified according to categories of follow-up procedures recommended by the American Gastroenterology Association (AGA). Results We estimated that by 1 and 5 year(s) after diagnosis with celiac disease, 41.0% and 88.7% of the patients had follow-up visits, 33.6% and 79.8% were assessed for compliance with a gluten-free diet, 3.3% and 15.8% met with a registered dietitian, 2.5% and 18.1% had an additional intestinal biopsy, and 22.1% and 65.6% received serologic testing for markers of celiac disease. Among 113 patients (93%) who were followed for more than 4 years, only 35% received follow-up analyses that were consistent with AGA recommendations. Conclusions Patients with celiac disease are not followed consistently. Follow-up examinations are often inadequate and do not follow AGA recommendations. Improving follow-up strategies for patients with celiac disease could improve management of this disease. PMID:22610009

  6. Maintenance of an Adequate Dental Hygiene Education System.

    Ley, Eugene; And Others

    1984-01-01

    Administrative decisions about the future of dental hygiene programs are often based on inadequate information about employment trends and about the importance of the dental hygienist in dental practices. Studies indicate that demand for dental hygiene services will remain high in the 1980s. (Author/MLW)

  7. The Alchemy of "Costing Out" an Adequate Education

    Hanushek, Eric A.

    2006-01-01

    In response to the rapid rise in court cases related to the adequacy of school funding, a variety of alternative methods have been developed to provide an analytical base about the necessary expenditure on schools. These approaches have been titled to give an aura of a thoughtful and solid scientific basis: the professional judgment model, the…

  8. Estimating the Cost of an Adequate Education in New York

    William Duncombe

    2002-01-01

    The New York State Board of Regents and Commissioner of Education have identified a set of clear performance standards for students in New York State that matches the knowledge and skills they will need to function successfully as productive citizens in the 21st century. To match these standards, the New York State Department of Education has developed new Regents Examinations, which all students will be required to pass to graduate from high school, and new examinations in 4th and 8th grades...

  9. Using Adequate Ball Bearings in RC Car Chassis

    Lucian Fridrik

    2011-06-01

    Full Text Available The paper presents the usage and misusage of ball bearings in rc car chassis technology of today . As this area is under massive development and could have a great impact in real cars it is important for new researchers to understand the importance of using the correct parts in constructing new devices and technologies based on the current one. As problems in economy are increasing it is important for new discovery’s to be tested in small scale models rather than full scale.

  10. ACHIEVEMENT FOR WIRELESS COMMUNICATION USING ADEQUATE MLTI-THREDING ARCHITECTURES

    Rajeev Ranjan; Praveen Dhyani; Rajeev Kumar

    2015-01-01

    A major role is played in the layout and evaluation of any empirical wireless structure to manifest is the goal of this paper that counterfeit mode architectures affect counterfeit conduct, regarding structure accomplishment metrics, essentially and therefore, the excellent architecture should be explored in order to accomplish the most accurate and reliable results. It is found that the most analytical factors it is found that that actuate counterfeit mode accomplishment are coun...

  11. Standards for securing adequate indoor air quality across Europe

    Wargocki, Pawel; Carrer, P.; de Oliveira Fernandes, E.;

    2013-01-01

    human bioeffluents and is determined mainly considering the metabolic CO2 production. It is only applicable if all other pollutants meet WHO guidelines for ambient and indoor air quality. If they do not meet these guidelines after applying source control and when air used for ventilation is clean health...

  12. Adequateness of applying the Zmijewski model on Serbian companies

    Pavlović Vladan

    2012-12-01

    Full Text Available The aim of the paper is to determine the accuracy of the prediction of Zmijewski model in Serbia on the eligible sample. At the same time, the paper identifies model's strengths, weaknesses and limitations of its possible application. Bearing in mind that the economic environment in Serbia is not similar to the United States at the time the model was developed, Zmijewski model is surprisingly accurate in the case of Serbian companies. The accuracy was slightly weaker than the model results in the U.S. in its original form, but much better than the results model gave in the U.S. in the period 1988-1991, and 1992-1999. Model gave also better results in Serbia comparing those in Croatia, even in Croatia model was adjusted.

  13. Origin and adequate model of coalescence in quiescent polymer blends

    Fortelný, Ivan

    Praha : Institute of Macromolecular Chemistry, 2009. s. 159. ISBN 978-80-85009-59-0. [Prague Meetings on Macromolecules /73./ New Frontiers in Macromolecular Science: From Macromolecular Concepts of Living Matter to Polymers for Better Quality of Life . 05.07.2009-09.07.2009, Prague] R&D Projects: GA AV ČR IAA200500903 Institutional research plan: CEZ:AV0Z40500505 Keywords : coalescence * polymer blends * Ostwald ripening * quiescent state Subject RIV: CD - Macromolecular Chemistry

  14. 34 CFR 200.13 - Adequate yearly progress in general.

    2010-07-01

    ... of the State and of all public schools and LEAs in the State— (1) Toward enabling all public school... narrowing the achievement gaps in the State, its LEAs, and its public schools. (b) A State must define... continuous and substantial academic improvement for all students; (4) Measures the progress of all...

  15. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    2010-01-01

    ... maintained at all times, including maintenance of accountability records showing disposition of input and output documents. (3) All persons whose duties require access to processing and maintenance...

  16. Are physiotherapy students adequately prepared to successfully gain employment?

    McIntyre, J.; Naylor, S.

    2010-01-01

    This is the post-print version of the final paper published in Physiotherapy. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V. Objectives - To explore the preparedness of final-year...

  17. Dose limits for man do not adequately protect the ecosystem

    As has been noted by both of our participants, it is interesting to see that their views approached agreement during the course of the debate. This is not altogether unexpected since the topic is one that has many facets. It is fair to say that protecting man is an appropriate starting point for the protection of other more, or less, radiosensitive life forms sharing the planet with us. That there may be special situations requiring attention has been recognized by both of our participants. That the ICRP recognizes the need for further work on this topic is encouraging for ourselves as well as the 'bugs and bunnies'. (authors)

  18. Decontamination of laryngoscope blades: Is our practice adequate?

    Telang R

    2010-01-01

    Full Text Available Background : The laryngoscope has been identified as a potential source of cross-infection, because of blood and bacterial contamination. In India, there are no guidelines for cleaning and disinfection of anesthesia-related equipment. Practices for decontamination of laryngoscopes vary widely and in most healthcare institutes, laryngoscope blades are re-used after cleaning with tap-water. Materials and Methods: We prospectively compared two techniques for decontamination of laryngoscope blades - a washing with tap-water and b washing with tap-water followed by disinfection by immersing in 5% v/v (volume/volume, 1:20 dilution aldehyde-free biguanide agent for 10 min. We calculated the cost-effectiveness of using 5% v/v aldehyde-free biguanide agent for disinfection of laryngoscopes. We also conducted a survey to assess the decontamination practices in other Indian hospitals. Results : Overall bacterial growth was 58% (29 out of 50 blades after tap-water cleaning (of which 60% were pathogenic organisms versus 3.4% (one out of 29 blades after tap-water cleaning followed by immersion in disinfectant (all of which were commensals. The cost of disinfection with biguanide was Indian Rupees 1.13 (20 US cents per laryngoscope. Most hospitals in India do not have guidelines regarding laryngoscope decontamination between uses, and cleaning with tap water is a commonly used method. Conclusion : Cleaning of laryngoscope blades with tap-water is a commonly used but inadequate method for decontamination. Washing with tap-water followed by disinfection with 5% v/v aldehyde-free biguanide for at least 10 min is an effective and inexpensive alternative. National guidelines for the decontamination of anesthesia equipment are necessary.

  19. Decontamination of laryngoscope blades: Is our practice adequate?

    Telang R; Patil V; Ranganathan P; Kelkar R

    2010-01-01

    Background : The laryngoscope has been identified as a potential source of cross-infection, because of blood and bacterial contamination. In India, there are no guidelines for cleaning and disinfection of anesthesia-related equipment. Practices for decontamination of laryngoscopes vary widely and in most healthcare institutes, laryngoscope blades are re-used after cleaning with tap-water. Materials and Methods: We prospectively compared two techniques for decontamination of laryngoscope blade...

  20. Are antibiotic screening approaches sufficiently adequate? A proficiency test

    Berendsen, B.J.A.; Pikkemaat, M.G.; Stolker, A.A.M.

    2011-01-01

    A proficiency test including the screening analysis of antibiotics in beef using cryogenicly minced materials was organized by RIKILT in 2009. The test included blank beef samples and beef samples spiked with either flumequine or a combination of lincomycin and spectinomycin around the maximum resid

  1. Human subject protection In India - Is it adequate?

    Narges Mahaluxmivala

    2010-01-01

    Full Text Available India′s experience in clinical trials is shorter in time than that of the developed countries but as in everything else in the current globalizing environment, business compulsions characterized by compressed timelines are strong persuaders to catch up. Most global pharmaceutical and biotechnology organizations include India in their strategic plans, Immediate implementation of aspects that attract benefit are an urgent necessity. Technical and ethical issues that remain unresolved constrain India from reaching its deserved potential. To take fullest advantage of the current inflow of clinical trials, India must adopt, without delay, an all-inclusive approach and invest in a widespread and comprehensive GCP-compliance programme taking into account India-related cultural and socioeconomic issues. The initiative should not be allowed to flag. Government, the pharmaceutical and biotechnological research industries, the medical and pharmacy profession including relevant training institutes, the media and the public have a stake in such investment. The programme should involve assessing gaps in current clinical trial compliance measures and possible solutions, set the field for rectification and ensure implementation through mandate and penalty as feasible.

  2. SNAP benefits: Can an adequate benefit be defined?

    Yaktine, Ann L; Caswell, Julie A

    2014-01-01

    The Supplemental Nutrition Assistance Program (SNAP) increases the food purchasing power of participating households. A committee convened by the Institute of Medicine (IOM) examined the question of whether it is feasible to define SNAP allotment adequacy. Total resources; individual, household, and environmental factors; and SNAP program characteristics that affect allotment adequacy were identified from a framework developed by the IOM committee. The committee concluded that it is feasible to define SNAP allotment adequacy; however, such a definition must take into account the degree to which participants' total resources and individual, household, and environmental factors influence the purchasing power of SNAP benefits and the impact of SNAP program characteristics on the calculation of the dollar value of the SNAP allotment. The committee recommended that the USDA Food and Nutrition Service investigate ways to incorporate these factors and program characteristics into research aimed at defining allotment adequacy. PMID:24425718

  3. SNAP Benefits: Can an Adequate Benefit Be Defined?123

    Yaktine, Ann L.; Caswell, Julie A.

    2014-01-01

    The Supplemental Nutrition Assistance Program (SNAP) increases the food purchasing power of participating households. A committee convened by the Institute of Medicine (IOM) examined the question of whether it is feasible to define SNAP allotment adequacy. Total resources; individual, household, and environmental factors; and SNAP program characteristics that affect allotment adequacy were identified from a framework developed by the IOM committee. The committee concluded that it is feasible ...

  4. Do British travel agents provide adequate health advice for travellers?

    Lawlor, D A; J. Burke; Bouskill, E; Conn, G; Edwards, P.; Gillespie, D.

    2000-01-01

    Travel-related illness is a burden for primary care, with more than two million travellers consulting a general practitioner each year. The annual cost of travel-related illness in the United Kingdom is 11 million Pounds. Travel agents are in a unique position to influence this burden as the most common and most serious problems are preventable with simple advice and/or immunisation. This study, using covert researchers, suggests this potential is not being fully utilised.

  5. Method for ensuring adequate reverse circulation during drilling

    Kosnyrev, B.A.; Spivak, A.I.

    1984-01-01

    One of the methods to reduce hydrodynamic pressure fluctuation within the drill bit work zone is the utilization of special attachments that go over the bit. A device has been developed by the central laboratory of Orenburgneft jointly with the Ufa Oil Institute that utilizes multi-nozzle high-pressure jet pumps. Unit is mounted directly above the bit and assures reverse circulation. This paper provides formulas to determine the rational operation requirements of units during drilling. A nomogram has been plotted that makes it possible to select the necessary parameters for the unit as well as rational geometric parameters of the jet pumps. Use of unit makes it possible to stabilize operation of drill bit by providing small spaces between body of unit and the well wall and thus facilitate conditions under which rock is crushed at bottomhole, and eliminating negative effects of hydrodynamic pressure fluctuations. This method makes it possible to use less drilling mud and reduce the drill bit load.

  6. Standards for securing adequate indoor air quality across Europe

    Wargocki, Pawel; Carrer, P.; de Oliveira Fernandes, E.; Hanninen, O.; Popov, T.

    Background: Inadequate IAQ causes a loss of 2 million healthy life years annually in the EU. Europeans spend typically over 85–90% of their time indoors and the main factors that affect negatively the characteristics of the air they breathe are outdoor air used to ventilate indoor spaces and indoor...... studies improperly characterised exposures and because of their inhomogenity. Risk modelling simulations of different strategies resulting in reduction of DALYs suggested that healthbased ventilation requirements should be combined with source control strategies and if necessary cleaning of outdoor air in...... human bioeffluents and is determined mainly considering the metabolic CO2 production. It is only applicable if all other pollutants meet WHO guidelines for ambient and indoor air quality. If they do not meet these guidelines after applying source control and when air used for ventilation is clean health...

  7. An Adequate Password Authentication Scheme for Information Interchange using Keys

    S Sandeep Babu; N. Subhash Chandra

    2014-01-01

    The Scheme that is followed in general today’s date applications is that the data transfer will go on in a normal way where there is no security provided to data and to make sure that the data is protected from intruders we are implementing this idea where initially the connection between client and server will happen based upon the authentication key provided by client for connection and moreover once the connection is established we can say that the application is half way protected and to ...

  8. [Phenomenology of craving: from differentiation to adequate therapy].

    Mendelevich, V D

    2010-01-01

    The author analyzes a phenomenon of addiction from the psychological/psychiatric position and differentiates it from psychopathological disorders, including parabulia, hyperbulia, paraphylia, commonly used for the definition of drive disorders. It has been concluded that addition is a specific complex of clinical symptoms which is not similar to other drive disorders. To avoid diagnostic and therapeutic errors, the author suggests to revise definitions by assigning the biological sense to the conception of addiction within psychoactive substance dependence and sexual addiction, some forms of eating dependence and to use the definition of paraaddictive drives in cases of over-valued drives (gambling, Internet dependence, fanaticism etc). PMID:21322141

  9. 34 CFR 200.20 - Making adequate yearly progress.

    2010-07-01

    ... paragraph (c)(1)(i) of this section if they take— (A) Either an assessment of English language proficiency under § 200.6(b)(3) or the State's reading/language arts assessment under § 200.2; and (B) The State's... English proficient students on the mathematics assessment, the reading/language arts assessment...

  10. Framework conditions for entrepreneurship in Norway: are they adequate?

    Tuft, Vibeke Holmvåg

    2009-01-01

    ABSTRACT This research investigates how four framework conditions for entrepreneurship in Norway can be improved. From interviews with the expert panel for framework conditions in the Global Entrepreneurship Monitor research project the framework conditions: Financial support, government policy, government programs and education and training are investigated. Using both a questionnaire and interviews with Norwegian experts on entrepreneurship, assessment of current status and areas for ...

  11. A quark mass definition adequate for threshold problems

    Beneke, Martin

    1998-01-01

    Recent calculations of heavy quark cross sections near threshold at next-to-next-to-leading order have found second-order corrections as large as first-order ones. We analyse long-distance contributions to the heavy quark potential in momentum and coordinate space and demonstrate that long-distance contributions in momentum space are suppressed as $\\Lambda_{QCD}^2/q^2$. We then show that the long-distance sensitivity of order $\\Lambda_{QCD} r$ introduced by the Fourier transform to coordinate space cancels to all orders in perturbation theory with long-distance contributions to the heavy quark pole mass. This leads us to define a subtraction scheme -- the `potential subtraction scheme' -- in which large corrections to the heavy quark potential and the `potential-subtracted' quark mass are absent. We compute the two-loop relation of the potential-subtracted quark mass to the $\\bar{MS}$ quark mass. We anticipate that threshold calculations expressed in terms of the scheme introduced here exhibit improved conver...

  12. Chronic Disease Management Programmes: an adequate response to patients’ needs?

    Rijken, M; Bekkema, N.; Boeckxstaens, P.; Schellevis, F G; De Maeseneer, J M; Groenewegen, P. P.

    2014-01-01

    Background: Inspired by American examples, several European countries are now developing disease management programmes (DMPs) to improve the quality of care for patients with chronic diseases. Recently, questions have been raised whether the disease management approach is appropriate to respond to patient-defined needs. Objective: In this article we consider the responsiveness of current European DMPs to patients needs defined in terms of multimorbidity, functional and participation problems,...

  13. Formal methods to model adequate task behaviour in complex scenarios

    Helsdingen, A.S.; Krimp, G.W.; Urlings, M.C.M.

    2006-01-01

    Modellering van tactische scenarios met extensieve speltheorie leidt tot identificatie van alle winnende taakstrategieen. maar deze techniek kan slechts beperkte hoeveelheid capaciteit aan. Reinforcment learning technieken leveren niet zulke optimale prestaties, maar kunnen in meer complexe scenario

  14. Are Academic Programs Adequate for the Software Profession?

    Koster, Alexis

    2010-01-01

    According to the Bureau of Labor Statistics, close to 1.8 million people, or 77% of all computer professionals, were working in the design, development, deployment, maintenance, and management of software in 2006. The ACM [Association for Computing Machinery] model curriculum for the BS in computer science proposes that about 42% of the core body…

  15. Open fireplace furnace as an adequate heating system

    Terbrack, E.

    The fireplace furnace is a furnace for the open fireplace. It is connected to the existing fuel-oil or gas central heating and is used for house heating and warm water preparation when the fire in the fireplace is on. It combines the romanticism of the open fireplace with the necessity of saving fuel oil and gas, ensuring heat supply.

  16. Teaching children with diabetes about adequate dietary choices.

    Maffeis, Claudio; Pinelli, Leonardo

    2008-02-01

    Recent recommendations by the American Diabetes Association suggest that children with type 1 diabetes should follow the recommendations for age, sex and body size of the general population. In the case of being overweight or obese, weight-control strategies should be applied. Adherence to recommendations should be pursued by continuous nutritional education that should start at the onset of diabetes and maintained by means of nutritional counselling to the family. The second main target of nutritional intervention is to encourage a reproducible daily meal plan that can be maintained by acquiring good habits when making nutritional choices. Finally, children and parents should be taught how to count carbohydrates, which would help them manage exceptions in their daily meal plan. Specifically, nutritional recommendations for children with diabetes focus on limiting the intake of foods of animal origin (red meat, cheese, cold cuts), moderating fat intake and promoting the intake of foods that naturally contain fibre (mainly vegetables, legumes, fruit). There are two at-risk periods in the lives of children when nutritional education procedures as well as diabetes care in general are less likely to be effective: early years of life and adolescence. In the case of very young children, new behavioural-based intervention strategies to help parents improve mealtimes could be useful in teaching diabetic children to learn to follow a structured eating schedule, which is desirable for long-lasting efficacy in diabetes care. In adolescents, eating disorders and insulin misuse for weight control purposes are concrete and difficult problems to deal with. A good balance between eating for pleasure and maintaining one's health is a challenge for anyone. Appropriate nutritional education helps children with diabetes to find this balance and enjoy a better quality of life. PMID:18257950

  17. Crystallization and preliminary X-ray crystallographic analysis of bacterial tRNA(Sec) in complex with seryl-tRNA synthetase.

    Itoh, Yuzuru; Sekine, Shun Ichi; Yokoyama, Shigeyuki

    2012-06-01

    Selenocysteine (Sec) is translationally incorporated into proteins in response to the UGA codon. The tRNA specific to Sec (tRNA(Sec)) is first ligated with serine by seryl-tRNA synthetase (SerRS). To elucidate the tertiary structure of bacterial tRNA(Sec) and its specific interaction with SerRS, the bacterial tRNA(Sec) from Aquifex aeolicus was crystallized as the heterologous complex with the archaeal SerRS from Methanopyrus kandleri. Although X-ray diffraction by crystals of tRNA(Sec) in complex with wild-type SerRS was rather poor (to 5.7 Å resolution), the resolution was improved by introducing point mutations targeting the crystal-packing interface. Heavy-atom labelling also contributed to resolution improvement. A 3.2 Å resolution diffraction data set for phase determination was obtained from a K(2)Pt(CN)(4)-soaked crystal. PMID:22684069

  18. Adecuación de la Calidad Microbiológica de Desechos de Lagunas de Estabilización por la Aplicación de Ozono Microbiological Quality Adequation of Effluents from Secondary Lagoons by the Application of Ozone

    Luci Sartori

    2007-01-01

    Full Text Available Se evalúa la acción del ozono en la desinfección de desechos secundarios de alcantarillado sanitario, usando como microorganismos indicadores Escherichia coli, colifagos y Clostridium perfringens. Los desechos secundarios utilizados provenían de las plantas de tratamiento de las ciudades de Lins y Araraquara en Brasil. Los resultados mostraron que valores de concentración de ozono en el agua 29, 54, 82, 164 y 246 mg min /L para el desecho de Lins y de 25, 95, 142, 147, 189, 220 y 294 mg min /L de Araraquara, fueron adecuados, de acuerdo con los valores establecidos por la Organización Mundial de la Salud, en lo referente a la concentración de E. coli, para su uso en el regadío de cultivos. Se concluye que la aplicación de ozono, para regular la calidad microbiológica de los desechos de alcantarillado es adecuada. Sin embargo, la eficiencia de desinfección es afectada por el tratamiento previo que se realiza a los desechos.The disinfection of secondary effluents with ozone using Escherichia coli, coliphages and Clostridium perfringens as indicator microorganisms was evaluated. The secondary effluents of Lins Wastewater Treatment Plant and Araraquara in Brazil, were used. The results showed that values of ozone-in-water concentration of 29, 54, 82, 164 and 246 mg min /L for Lins effluent and 25, 95, 142, 147, 189, 220 and 294 mg min /L for Araraquara effluent were adequate, according to the standards of the World Health Organization for unrestricted irrigation, considering only E. coli concentration. It is concluded that the application of ozone to regulate the microbiological quality of the wastewaters is adequate. However, the efficiency of disinfection is affected by the previous treatment given to the wastes.

  19. Development of assessment methods concerning the individual radiation sensitivity using expression analysis of adequate candidate genes (StSsch 4212 project follow-up). Final report FuE project StSch 4405. 1.12.2003 to 30.11.2005; Entwicklung von Verfahren zur Erkennung individueller Strahlenempfindlichkeit durch Analyse der Expression geeigneter Kandidatengene (Folgeprojekt von StSch 4212). Schlussbericht FuE Vorhaben StSch 4405. Laufzeit 1.12.2003 bis 30.11.2005

    Schmezer, P.; Popanda, O. [DKFZ, Heidelberg (Germany). Toxikologie und Krebsrisikofaktoren; Chang-Claude, J. [DKFZ, Heidelberg (Germany). Klinische Epidemiologie; Debus, J. (comps.) [Heidelberg Univ. (Germany). Radiologische Klinik, Abt. Radioonkologie und Strahlentherapie

    2007-07-01

    The assessment of radiation hazards within radiotherapy and radiation protection needs the knowledge on the individual radiation sensitivity. The clinical experience shows since many years that patients react to radiotherapy with very different side reactions, beginning with skin or mucous membrane irritations and necrosis up to radiation induced death. Up to now there is no methodology available that allows identification of radiation sensitive persons. The project was aimed to develop adequate biomarkers.

  20. Programa Restaurante Popular: uma alternativa para promover o direito humano à alimentação adequada?(Popular Restaurant Program: an alternative to promote the human right to adequate food? Doi: 10.5212/Emancipacao.v.15i1.0009

    Fábio Resende de Araújo

    2016-05-01

    Full Text Available Resumo: O artigo objetiva identificar elementos relacionados ao Direito Humano à Alimentação Adequada (DHAA na compreensão de que os usuários possuem do Programa Restaurante Popular. A coleta de dados foi realizada em uma das unidades do Programa Restaurante Popular situada no Bairro do Alecrim, em Natal, Rio Grande do Norte. Foram entrevistados 295 usuários. A representação que os usuários fazem do Restaurante Popular envolve três categorias: auxílio, alimentação de qualidade e economia financeira. Em relação às motivações para a existência do Restaurante, os usuários reportaram-se a duas categorias: assistencialismo e obrigação do Estado. Conclui-se que os usuários não possuem uma percepção da política como direito, mas a percebem como mais uma política assistencialista.Palavras-chave: Direitos Humanos. Segurança Alimentar Nutricional. Políticas Públicas.Abstract: The article aims to identify factors related to the Human Right to Adequate Food (DHAA on the understanding that users have the Program Popular Restaurant. Data collection was carried out in one of the units of the Program Popular restaurant located in the neighborhood of Alecrim in Natal, Rio Grande do Norte. Were interviewed 295 users. The representation that users make restaurant Popular involves three categories: assistance, food quality and financial savings. Regarding the motivations for the existence of restaurant users reported up to two categories: assistentialism and state obligation. The conclusion is that users do not have a perception of politics as a right but perceive it as more of a welfare policy.Keywords: Human Rights. Food Security and and Nutrition. Public Policy.