Science.gov

Sample records for acid ribonucleic acid

  1. Ribonucleic acid purification.

    PubMed

    Martins, R; Queiroz, J A; Sousa, F

    2014-08-15

    Research on RNA has led to many important biological discoveries and improvement of therapeutic technologies. From basic to applied research, many procedures employ pure and intact RNA molecules; however their isolation and purification are critical steps because of the easy degradability of RNA, which can impair chemical stability and biological functionality. The current techniques to isolate and purify RNA molecules still have several limitations and the requirement for new methods able to improve RNA quality to meet regulatory demands is growing. In fact, as basic research improves the understanding of biological roles of RNAs, the biopharmaceutical industry starts to focus on them as a biotherapeutic tools. Chromatographic bioseparation is a high selective unit operation and is the major option in the purification of biological compounds, requiring high purity degree. In addition, its application in biopharmaceutical manufacturing is well established. This paper discusses the importance and the progress of RNA isolation and purification, considering RNA applicability both in research and clinical fields. In particular and in view of the high specificity, affinity chromatography has been recently applied to RNA purification processes. Accordingly, recent chromatographic investigations based on biorecognition phenomena occurring between RNA and amino acids are focused. Histidine and arginine have been used as amino acid ligands, and their ability to isolate different RNA species demonstrated a multipurpose applicability in molecular biology analysis and RNA therapeutics preparation, highlighting the potential contribution of these methods to overcome the challenges of RNA purification. PMID:24951289

  2. The quantitative histochemistry of ribonucleic acid using gallocyanin.

    PubMed

    Brown, A; Scholtz, C L

    1979-03-01

    A method for the cytophotometric estimation of ribonucleic acid in tissue sections using gallocyanin-chrome alum is described. The dye obeys Beer's law in gelatin sections. The effect of deoxyribonuclease on the staining of ribonucleic acid is also investigated. The results indicate that this method is of value in the quantitation of ribonucleic acid. PMID:91237

  3. Ribonucleic acid and ribosomes of Bacillus stearothermophilus.

    PubMed

    Saunders, G F; Campbell, L L

    1966-01-01

    Saunders, Grady F. (University of Illinois, Urbana), and L. Leon Campbell. Ribonucleic acid and ribosomes of Bacillus stearothermophilus. J. Bacteriol. 91:332-339. 1966.-The ability of some thermophilic bacteria to grow at temperatures as high as 76 C emphasizes the remarkable thermal stability of their crucial macromolecules. An investigation of the ribonucleic acid (RNA) and ribosomes of Bacillus stearothermophilus was conducted. Washed log-phase cells were disrupted either by sonic treatment or by alumina grinding in 10(-2)m MgCl(2)-10(-2)m tris-(hydroxymethyl)aminomethane buffer, pH 7.4 (TM buffer). Ultracentrifugal analysis revealed peaks at 72.5S, 101S, and 135S, with the 101S peak being the most prominent. By lowering the Mg(++) concentration to 10(-3)m, the ribosome preparation was dissociated to give 40S, 31S, and 54S peaks. These in turn were reassociated in the presence of 10(-2)m Mg(++) to give the larger 73S and 135S particles. When heated in TM buffer, Escherichia coli ribosomes began a gradual dissociation at 58 C, and at 70 C underwent a large hyperchromic shift with a T(m) at 72.8 C. In contrast, B. stearothermophilus ribosomes did not show a hyperchromic shift below 70 C; they had a T(m) of 77.9 C. The thermal denaturation curves of the 4S, 16S, and 23S RNA from both organisms were virtually identical. The gross amino acid composition of B. stearothermophilus ribosomes showed no marked differences from that reported for E. coli ribosomes. These data suggest that the unusual thermal stability of B. stearothermophilus ribosomes may reflect either an unusual packing arrangement of the protein to the RNA or differences in the primary structure of the ribosomal proteins. PMID:5903099

  4. Ribonucleic acid (RNA) biosynthesis in human cancer.

    PubMed

    Hajjawi, Omar S

    2015-01-01

    In many respects, the most remarkable chemical substances within the genome of eukaryotic cells are remarkable proteins which are the critical structural and functional units of living cells. The specifications for everything that goes in the cell are natural digital-to-digital decoding process in an archive sequence by deoxyribonucleic acid (DNA) and an articulate construction by ribonucleic acid (RNA). The products of DNA transcription are long polymers of ribonucleotides rather than deoxyribonucleotides and are termed ribonucleic acids. Certain deoxyribonucleotide sequences, or genes, give rise to transfer RNA (tRNA) and other ribosomal RNA (rRNA) when transcribed. The ribonucleotide sequences fold extensively and rRNA is associated with specific proteins to yield the essential cell components, ribosomes. Transcription of other special sequences yields messenger RNAs (mRNAs) that contain ribonucleotide sequences that will be ultimately translated into new types of amino acid sequences of functional cellular protein molecules. This switch to a different variety of cellular molecular sequences is complex, but each sequence of the three ribonucleotides specifies the insertion of one particular amino acid into the polypeptide chain under production. Whilst mRNA is considered the vehicle by which genetic information is transmitted from the genome and allocated in the appropriate cytoplasmic sites for translation into protein via cap-dependent mechanism, the actual translation depends also on the presence of other so-called household and luxury protein molecules. Recent evidence suggests RNA species are required at initiation, because treatment of cells with antibiotics or drugs that inhibit RNA synthesis cause a decrease in protein synthesis. The rRNA is necessary as a structural constituent of the ribosomes upon which translation takes place, whereas tRNA is necessary as an adaptor in amino acid activation and elongation protein chains to ribosomes. In this article

  5. Ribonucleic Acid Regulation in Permeabilized Cells of Escherichia coli Capable of Ribonucleic Acid and Protein Synthesis1

    PubMed Central

    Atherly, Alan G.

    1974-01-01

    A cell permeabilization procedure is described that reduces viability less than 10% and does not significantly reduce the rates of ribonucleic acid and protein synthesis when appropriately supplemented. Permeabilization abolishes the normal stringent coupling of protein and ribonucleic acid synthesis. PMID:4364330

  6. Ribonucleic acid interference (RNAi) and control of citrus pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ribonucleic acid interference, RNAi, applications and function are described for the non-scientist to bring a better understanding of how this emerging technology is providing environmentally friendly, non-transgenic, insect pest control. ...

  7. Distribution of ribonucleic acid coliphages in animals.

    PubMed Central

    Osawa, S; Furuse, K; Watanabe, I

    1981-01-01

    To determine the distribution pattern of ribonucleic acid (RNA) coliphages (classified by serological groups I through IV) in animal sources, we isolated RNA phages from (i) feces samples from domestic animals (cows, pigs, horses, and fowls), some other animals in a zoological garden, and humans, (ii) the gastrointestinal contents of cows and pigs, and (iii) sewage samples from treatment plants in slaughter houses. These samples were then analyzed serologically. The concentration of RNA phages in the first and second kinds of material was fairly low (10 to 10(3) plaque-forming units per original phage sample), whereas that in the third kind of material was fairly high (10(3) to 10(5) plaque-forming units per original phage sample). Concerning the group types of the RNA phages in the first and second kinds of material, human feces contained RNA phages of groups II and III almost equally, the gastrointestinal contents of pigs included those of groups I and II equally, and the feces or gastrointestinal contents of other mammals other than humans and pigs had those of group I exclusively. In the third type of material we found mostly group I phages with a minor fraction of group II phages. Thus, the prominent features of the distribution pattern of RNA phages are the predominance of groups III and II in humans and the predominance of group I in animals. PMID:7224619

  8. PolyGuanine methacrylate cryogels for ribonucleic acid purification.

    PubMed

    Köse, Kazım; Uzun, Lokman

    2016-05-01

    The isolation and purification of ribonucleic acid have attracted attention recently for the understanding of the functions in detail because of the necessity for the treatment of genetic diseases. In this study, guanine-incorporated polymeric cryogels were developed to obtain highly purified ribonucleic acid. The satisfactory purification performance was achieved with the guanine-incorporated poly (2-hydroxyethyl methacrylate-guanine methacrylate) cryogels. The most crucial advantages to use guanine as a functional monomer are to obtain a real natural interaction between guanine on the polymeric material and cytosine on the ribonucleic acid. Moreover, using cryogel with a highly porous structure and high swelling ratio provide advantages of getting more water within the structure to get more analyte to interact. The characterization of cryogels has proved the success of the synthesis and the perfect natural interaction to be taken place between the ligand (guanine methacrylate) and the cytosine in the ribonucleic acid molecules. Although the pores within the structure of cryogels are small, they provide efficient and fast adsorption. The chromatographic separation performance was investigated for different conditions (pH, temperature etc.). The desorption ratio and reusability were also analyzed at the end of the five adsorption-desorption cycles with no significant changes. PMID:27004613

  9. Saliva of Lygus lineolaris digests double stranded ribonucleic acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prospects for development of highly specific pesticides based on double stranded ribonucleic acid have been a recent focus of scientific research. Creative applications have been proposed and demonstrated. However, not all insects are sensitive to double stranded RNA (dsRNA) gene knockdown effec...

  10. INFECTIVITY OF HISTONE-POLIOVIRUS RIBONUCLEIC ACID PREPARATIONS.

    PubMed

    LUDWIG, E H; SMULL, C E

    1963-06-01

    Ludwig, Ernest H. (The Pennsylvania State University, University Park) and Christine E. Smull. Infectivity of histone-poliovirus ribonucleic acid preparations. J. Bacteriol. 85:1334-1338. 1963.-Some properties of histone-poliovirus ribonucleic acid (RNA) preparations, as relate to infectivity for HeLa cell monolayers, were investigated. The histone-RNA preparations were found to lose their infectivity rapidly at room temperature. They were considerably more stable at ice-bath temperature. Dilution of a histone-RNA preparation in a diluent containing an appropriate amount of histone yielded a plaque count which was proportional to the dilution factor, and which regressed linearly through the point of origin. Dilution of a histone-RNA preparation in a diluent containing no histone resulted in a rapidly decreasing plaque count which was not proportional to the dilution factor. The ability of histone to enhance the infectivity of poliovirus RNA was found to be dependent upon the presence of a low concentration of a monovalent salt in the histone-RNA preparations. Histone-RNA preparations containing approximately isotonic levels of NaCl exhibited a high degree of infectivity. When concentrations of NaCl outside this range were used, a great loss in infectivity of the histone-RNA preparations occurred. The NaCl could be replaced by KCl but not by CaCl(2), MgCl(2), or MgSO(4). PMID:14047226

  11. Ribonucleic acid synthesis during fruiting body formation in Myxococcus xanthus.

    PubMed

    Smith, B A; Dworkin, M

    1981-04-01

    A method has been devised that allowed us, for the first time, to pulse-label M. xanthus cells with precursors for ribonucleic acid biosynthesis while they were undergoing fruiting body formation. Using this method, we examined patterns of ribonucleic acid (RNA) accumulation throughout the process of fruiting body formation. As development proceeded, the rate of RNA accumulation increased at two periods of the developmental cycle: once just before aggregation and once late in the cycle, when sporulation was essentially completed. In contrast to vegetatively growing cells, in which only stable RNA species are labeled during a 30-min pulse, the majority of radioactivity found in RNA from 30-min pulse-labeled developing cells was found in an unstable heterodisperse fraction that migrated to the 5S to 16S region of sucrose density gradients and sodium dodecyl sulfate-polyacrylamide gels. This pattern of incorporation could not be induced (i) by a shift down of vegetatively growing cells to a nutritionally poor medium, in which the generation time was increased to that of developing cells during the growth phase, or (ii) by plating of vegetative cells onto the same solid-surface environment as that of developing cells, but which surface supported vegetative growth rather than fruiting body formation. Thus, the RNA synthesis pattern observed appeared to be related to development per se rather than to nutritional depletion or growth on a solid surface alone. The radioactivity incorporated into the unstable 5S to 16S RNA fraction accumulated as the pulse length was increased from 10 to 30 min; in contrast, an analogous unstable fraction from vegetative cells decreased as pulse length was increased. This suggested that developmental 5S to 16S RNA was more stable than vegetative cell 5S to 16S RNA (presumptive messenger RNA). However, during a 45-min chase period, radioactivity in 30-min-pulse-labeled developmental 5S to 16S RNA decayed to an extent twice that of

  12. Interferon action on parental Semliki forest virus ribonucleic acid.

    PubMed

    Friedman, R M; Fantes, K H; Levy, H B; Carter, W B

    1967-12-01

    Actinomycin D-treated chick fibroblasts were infected with purified (32)P-labeled Semliki forest virus, and ribonucleic acid (RNA) was extracted after 1 or 2 hr. Within 1 hr, viral RNA forms sedimenting in sucrose gradients at 42S, 30S, and 16S were present. The 42S form corresponded to the RNA of the virion. The 16S form appeared to be a double-stranded template for the formation of new viral RNA, since nascent RNA was associated with it and the molecule could be heat-denatured and subsequently reannealed by slow cooling. Interferon treatment before infection, or puromycin (50 mug/ml) or cycloheximide (200 mug/ml) added at the time of virus infection, had no effect on the formation of the 30S RNA but inhibited the production of the 16S form. Several findings made it unlikely that these results were due to breakdown of parental RNA and reincorporation of (32)P into progeny structures. The results suggested that the mechanism of interferon action involves inhibition of protein synthesis by parental viral RNA, since a specific viral RNA polymerase had previously been demonstrated to be necessary for production of 16S RNA. No protein synthesis appears necessary for formation of 30S RNA from parental virus RNA. PMID:5621488

  13. Effect of Ethionine on the Ribonucleic Acid, Deoxyribonucleic Acid, and Protein Content of Escherichia coli

    PubMed Central

    Smith, Robert C.; Salmon, W. D.

    1965-01-01

    Smith, Robert C. (Auburn University, Auburn, Ala.), and W. D. Salmon. Effect of ethionine on the ribonucleic acid, deoxyribonucleic acid, and protein content of Escherichia coli. J. Bacteriol. 89:687–692. 1965.—The addition of ethionine to cultures of Escherichia coli K-12 W6, a methionine-requiring auxotroph, led to inhibition of the rate of increase in optical density when the ratio of ethionine to methionine was 200:1. When the ratio was 600:1, the increase in optical density became linear. When ethionine was substituted for methionine in the medium, the optical density of the culture increased, and there was a parallel increase in protein content. There was no cell division in these cultures. The rate of synthesis of ribonucleic acid (RNA) in a culture containing ethionine was similar to that of a culture deprived of methionine, but the synthesis of deoxyribonucleic acid in a culture with ethionine was about twice that of a culture deprived of methionine. No detectable radioactivity from ethionine-ethyl-1-C14 was incorporated into RNA. Ethionine-ethyl-1-C14 was readily incorporated into the protein fraction. PMID:14273646

  14. Comparison of methods of extracting messenger Ribonucleic Acid from ejaculated Porcine (Sus Scrofa) Spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    H. D. Guthrie, G.R. Welch, and L. A. Blomberg. Comparison of Methods of Extracting Messenger Ribonucleic Acid from Ejaculated Porcine (Sus Scrofa) Spermatozoa. Biotechnology and Germplasm Laboratory, Agricultural Research Service U. S. Department of Agriculture, Beltsville, MD 20705 The purpos...

  15. Ribonucleic acid interference (RNAi) technology for control of Asian citrus psyllid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ribonucleic acid interference, RNAi, applications and function are described for the non-scientist to bring a better understanding of how this emerging technology is providing environmentally friendly, non-transgenic, insect pest control to the citrus industry. Two part Video presentation....

  16. Control of larval and egg development in Aedes aegypti with Ribonucleic acid interference (RNAi) against juvenile hormone acid methyl transferase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ribonucleic acid interference (RNAi) is a powerful approach for elucidating gene functions in a variety of organisms, including mosquitoes and many other insects. Little has been done, however, to harness this approach in order to control adult and larval mosquitoes. Juvenile hormone (JH) plays a pi...

  17. Effect of the “Ribonucleic Acid Control” Locus in Escherichia coli on T4 Bacteriophage-Specific Ribonucleic Acid Synthesis

    PubMed Central

    Sköld, Ola

    1970-01-01

    Amino acid control of ribonucleic acid (RNA) synthesis in bacteria is known to be governed genetically by the rel locus. We investigated whether the rel gene of the host would also exert its effect on the regulation of phage-specific RNA synthesis in T4 phage-infected Escherichia coli cells. Since T-even phage infection completely shuts off host macromolecular synthesis, phage RNA synthesis could be followed specifically by the cumulative incorporation of radioactivity from labeled precursors into RNA of infected cells. Labeled uracil was shown to accumulate in phage-specific RNA for 30 to 35 min after infection, a phenomenon which probably reflects an expansion of the labile phage-RNA pool. Amino acid starvation was effected by the use of auxotrophic bacterial strains or thienylalanine. The latter substance is an amino acid analogue which induces a chemical auxotrophy by inhibiting the biosynthesis of phenylalanine, tyrosine, and tryptophan. Phage RNA synthesis was strictly dependent on the presence of amino acids, whereas phage deoxyribonucleic acid synthesis was not. By the use of several pairs of bacterial strains which were isogenic except for the rel gene, it was demonstrated that amino acid dependence was related to the allelic state of this gene. If the rel gene was mutated, amino acid starvation did not restrict phage RNA synthesis. PMID:4914097

  18. Characterization of a Ribonucleic Acid Polymerase Activity Associated with Purified Cytoplasmic Polyhedrosis Virus of the Silkworm Bombyx mori1

    PubMed Central

    Lewandowski, L. J.; Kalmakoff, J.; Tanada, Y.

    1969-01-01

    Purified cytoplasmic-polyhedrosis virus has been found to have associated with it a polymerase activity capable of catalyzing the synthesis of virus-specific, single-stranded ribonucleic acid (RNA) from the double-stranded RNA genome. PMID:16789118

  19. [Role of non-coding regulatory ribonucleic acids in chronic inflammatory diseases].

    PubMed

    Heinz, G A; Mashreghi, M-F

    2016-05-01

    Non-coding regulatory ribonucleic acids (RNA), including microRNA, long non-coding RNA and circular RNA, can influence the expression of genes mediating inflammatory processes and therefore affect the course and progression of chronic inflammatory diseases. Recent studies using antisense oligonucleotides suggest that such non-coding regulatory RNAs are suitable as novel therapeutic target molecules for the treatment of inflammatory rheumatic diseases. PMID:27115697

  20. Hydroxyquinolines inhibit ribonucleic acid-dependent deoxyribonucleic acid polymerase and inactivate Rous sarcoma virus and herpes simplex virus.

    PubMed

    Rohde, W; Mikelens, P; Jackson, J; Blackman, J; Whitcher, J; Levinson, W

    1976-08-01

    8-Hydroxyquinoline and several of its derivatives inactivate the transforming ability of Rous sarcoma virus and inhibit its ribonucleic acid-dependent deoxyribonucleic acid polymerase activity. The copper complex of these metal-binding ligands is as active as the free ligand. The activity of the 8-hydroxyquinolines is approximately 50-fold more effective than another group of metal-binding compounds that we have tested, the thiosemicarbazones. In contrast to the potency of the 8-hydroxyquinolines to inactivate Rous sarcoma virus, no intracellular inhibition of transformation could be demonstrated at a concentration that did not affect the growth and appearance of the cells. Cellular deoxyribonucleic acid synthesis was inhibited to a greater extent than was ribonucleic acid or protein synthesis. The phenomenon of "concentration quenching" was observed with high concentrations of drug, causing less inhibition of deoxyribonucleic acid synthesis than was observed with lower concentrations. Herpes simplex virus type 1 was inactivated also by the 8-hydroxyquinolines and their copper complexes. No intracellular inhibition of plaque formation was observed. Treatment with 8-hydroxyquinoline sulfate had no effect on the resolution of herpetic keratitis in rabbits. Some 8-hydroxyquinolines bind to deoxyribonucleic acid in the presence of copper, a phenomenon that may be important in their antiviral activity. PMID:185949

  1. Striking similarities are exhibited by two small Epstein-Barr virus-encoded ribonucleic acids and the adenovirus-associated ribonucleic acids VAI and VAII

    SciTech Connect

    Rosa, M.D.; Gottlieb, E.; Lerner, M.R.; Steitz, J.A.

    1981-09-01

    The nucleotide sequence of the region of the Epstein-Barr virus genome that specified two small ribonucleic acids (RNAs), EBER 1 and EBER 2, has been determined. Both of these RNAs are encoded by the right-hand 1,000 base pairs of the EcoRI J fragment of EBV deoxyribonucleic acid. EBER 1 is 166 (167) nucleotides long and EBER 2 is 172 +- 1 nucleotides long; the heterogeneity resides at the 3' termini. The EBER genes are separated by 161 base pairs and are transcribed from the same deoxyribonucleic acid strand. In vitro, both EBER genes can be transcribed by RNA polymerase III; sequences homologous to previously identified RNA polymerase III intragenic transcription control regions are present. Striking similarities are therefore apparent both between the EBERs and the two adenovirus-associated RNAs, VAI and VAII, and between the regions of the two viral genomes that specify these small RNAs. We have shown that VAII RNA as well as VAI RNA and the EBERs exist in ribonucleoprotein complexes which are precipitable by anti-La antibodies associated with systemic lupus erythematosus. Finally the authors have demonstrated that the binding of protein(s) from uninfected cells confers antigenicity on each of the four virus-encoded small RNAs.

  2. In Vitro Synthesis of Poliovirus Ribonucleic Acid: Role of the Replicative Intermediate

    PubMed Central

    Girard, Marc

    1969-01-01

    Poliovirus ribonucleic acid (RNA) polymerase crude extracts could be stored frozen in liquid nitrogen without loss of activity or specificity. The major in vitro product of these extracts was viral single-stranded RNA. However, after short periods of incubation with radioactive nucleoside triphosphates, most of the incorporated label was found in replicative intermediate. When excess unlabeled nucleoside triphosphate was added, the label was displaced from the replicative intermediate and accumulated as viral RNA. It is concluded from this experiment that the replicative intermediate is the precursor to viral RNA. In addition, some of the label was chased into double-stranded RNA. The implications of this finding are discussed. PMID:4306193

  3. Regulation of the Tyrosine Biosynthetic Enzymes in Salmonella typhimurium: Analysis of the Involvement of Tyrosyl-Transfer Ribonucleic Acid and Tyrosyl-Transfer Ribonucleic Acid Synthetase1

    PubMed Central

    Heinonen, J.; Artz, S. W.; Zalkin, H.

    1972-01-01

    Mutants of Salmonella typhimurium were isolated that require tyrosine for growth because of an altered tyrosyl-transfer ribonucleic acid (tRNA) synthetase. Extracts of one strain (JK10) contain a labile enzyme with decreased ability to transfer tyrosine to tRNATyr and a higher Km for tyrosine than the wild-type enzyme. Strain JK10 maintains repressed levels of the tyrosine biosynthetic enzymes when the growth rate is restricted due to limitation of charged tRNATyr. Several second-site revertants of strain JK10 exhibit temperature-sensitive growth due to partially repaired, heat-labile tyrosyl-tRNA synthetase. The tyrosine biosynthetic enzymes are not derepressed in thermosensitive strains grown at the restrictive temperature. A class of tyrosine regulatory mutants, designated tyrR, contains normal levels of tyrosyl-tRNA synthetase and tRNATyr. These results suggest that charging of tRNATyr is not necessary for repression. This conclusion is substantiated by the finding that 4-aminophenylalanine, a tyrosine analogue which causes repression of the tyrosine biosynthetic enzymes, is not attached to tRNATyr in vivo, nor does it inhibit the attachment reaction in vitro. A combined regulatory effect due to the simultaneous presence of tyrS and tyrR mutations in the same strain was detected. The possibility of direct participation of tyrosyl-tRNA synthetase in tyrosine regulation is discussed. PMID:4404819

  4. Transcription In Vitro by Reovirus-Associated Ribonucleic Acid-Dependent Polymerase 1

    PubMed Central

    Banerjee, A. K.; Shatkin, A. J.

    1970-01-01

    Digestion of purified reovirus type 3 with chymotrypsin degrades 70% of the viral protein and converts the virions to subviral particles (SVP). The SVP contain 3 of the 6 viral structural proteins and all 10 double-stranded ribonucleic acid (RNA) genome segments but not adenine-rich, single-stranded RNA. An RNA polymerase which is structurally associated with SVP transcribes one strand of each genome segment by a conservative mechanism in vitro. The single-stranded products include large (1.2 × 106 daltons), medium (0.7 × 106 daltons), and small (0.4 × 106 daltons) molecules which hybridize exclusively with the corresponding genome segments. The enzyme obtained by heating virions at 60 C synthesizes similar products. Kinetic and pulse-chase studies indicate that the different-sized products are synthesized simultaneously but at rates which are in the order: small > medium > large. Images PMID:5529847

  5. Inhibition of ribonucleic acid polymerase by a bacteriocin from Bacteroides fragilis.

    PubMed Central

    Mossie, K G; Robb, F T; Jones, D T; Woods, D R

    1981-01-01

    The Bacteroides fragilis bacteriocin which inhibits ribonucleic acid (RNA) polymerase activity had a narrow activity spectrum in vivo and only inhibited the growth of certain B. fragilis strains. In vitro the bacteriocin was not specific and inhibited RNA polymerases from widely diverse bacterial genera. RNA polymerases from rifampin-resistant strains of Bacteroides thetaiotaomicron and Clostridium acetobutylicum were resistant to the bacteriocin in vitro. Purified bacteriocin bound to partially purified RNA polymerase, and both proteins were cosedimented in a glycerol gradient. In the RNA polymerase reaction, the bacteriocin acted as a competitive inhibitor for adenosine, cytidine, and uridine 5'-triphosphates and as a noncompetitive inhibitor for guanosine 5'-triphosphate. The bacteriocin did not inhibit RNA polymerase from chicken embryos. PMID:6177280

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

    SciTech Connect

    Choubey, Amit; Nomura, Ken-ichi; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya

    2014-09-15

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

  7. The role of renin-angiotensin aldosterone system related micro-ribonucleic acids in hypertension

    PubMed Central

    Wang, Hui-Bo; Yang, Jun

    2015-01-01

    Micro-ribonucleic acids (miRNAs) are small (21-25 nucleotide) single-stranded, evolutionarily conserved non-protein-coding RNAs, which control diverse cellular functions by interacting with the 3’ untranslated region of specific target messenger RNAs at the post-transcriptional level. Research shows that an aberrant expression profile of miRNAs has been linked to a series of diseases, including hypertension. In the past few decades, it has been demonstrated that excessive activation of the renin-angiotensin aldosterone system (RAAS) involves in the pathogenesis of hypertension. This article reviews the latest insights in the identification of RAAS-correlative miRNAs and the potential mechanisms for their roles in hypertension. PMID:26446323

  8. Inhibition of isoleucyl-transfer ribonucleic acid synthetase in Echerichia coli by pseudomonic acid

    PubMed Central

    Hughes, Julia; Mellows, Graham

    1978-01-01

    The mode of action of the antibiotic pseudomonic acid has been studied in Escherichia coli. Pseudomonic acid strongly inhibits protein and RNA synthesis in vivo. The antibiotic had no effect on highly purified DNA-dependent RNA polymerase and showed only a weak inhibitory effect on a poly(U)-directed polyphenylalanine-forming ribosomal preparation. Chloramphenicol reversed inhibition of RNA synthesis in vivo. Pseudomonic acid had little effect on RNA synthesis in a regulatory mutant, E. coli B AS19 RCrel, whereas protein synthesis was strongly inhibited. In pseudomonic acid-treated cells, increased concentrations of ppGpp, pppGpp and ATP were observed, but the GTP pool size decreased, suggesting that inhibition of RNA synthesis is a consequence of the stringent control mechanism imposed by pseudomonic acid-induced deprivation of an amino acid. Of the 20 common amino acids, only isoleucine reversed the inhibitory effect in vivo. The antibiotic was found to be a powerful inhibitor of isoleucyl-tRNA synthetase both in vivo and in vitro. Of seven other tRNA synthetases assayed, only a weak inhibitory effect on phenylalanyl-tRNA synthetase was observed; this presumably accounted for the weak effect on polyphenylalanine formation in a ribosomal preparation. Pseudomonic acid also significantly de-repressed threonine deaminase and transaminase B activity, but not dihydroxyacid dehydratase (isoleucine-biosynthetic enzymes) by decreasing the supply of aminoacylated tRNAIle. Pseudomonic acid is the second naturally occurring inhibitor of bacterial isoleucyl-tRNA synthetase to be discovered, furanomycin being the first. PMID:365175

  9. Mutants of Salmonella typhimurium with an Altered Leucyl-Transfer Ribonucleic Acid Synthetase

    PubMed Central

    Alexander, Renee R.; Calvo, J. M.; Freundlich, M.

    1971-01-01

    Two trifluoroleucine-resistant mutants of Salmonella typhimurium, strains CV69 and CV117, had an altered leucyl-transfer ribonucleic acid (tRNA) synthetase. The mutant enzymes had higher apparent Km values for leucine (ca. 10-fold) and lower specific activities (ca. twofold) than the parent enzyme when tested in crude extracts. Preparations of synthetase purified ca. 60-fold from the parent and strain CV117 differed sixfold in their leucine Km values. In addition, the mutant enzyme was inactivated faster than the parent enzyme at 50 C. The growth rates of strains CV69 and CV117 at 37 C were not significantly different from that of the parent, whereas at 42 C strain CV69 grew more slowly than the parent. Leucine-, valine-, and isoleucine-forming enzymes were partially derepressed when the mutants were grown in minimal medium; the addition of leucine repressed these enzymes to wild-type levels. During growth in minimal medium, the proportion of leucine tRNA that was charged in the mutants was about 75% of that in the parent. The properties of strain CV117 were shown to result from a single mutation located near gal at minute 18 on the genetic map. These studies suggest that leucyl-tRNA synthetase is involved in repression of the enzymes required for the synthesis of branched-chain amino acids. PMID:4928008

  10. Incorporation of Mevalonic Acid into Ribosylzeatin in Tobacco Callus Ribonucleic Acid Preparations 1

    PubMed Central

    Murai, Norimoto; Armstrong, Donald J.; Skoog, Folke

    1975-01-01

    The incorporation of 14C-2-mevalonic acid into transfer RNA and ribosomal RNA (high molecular weight RNA) in rapidly growing, cytokinin-dependent tobacco (Nicotiana tabacum var. Wisconsin No. 38) callus cultures has been investigated. Approximately 40% of the label incorporated into transfer RNA was present in a ribonucleoside with chromatographic properties identical to those of cis-ribosylzeatin. The remainder of the label in the transfer RNA appears to be nonspecific incorporation resulting from degradation and metabolism of 14C-2-mevalonic acid by the tobacco callus tissue. Although the total radioactivity incorporated into ribosomal RNA was roughly the same as in transfer RNA, the specific radioactivity of the transfer RNA was about four times higher than that of the ribosomal RNA, and the ribosomal RNA labeling could be distinguished from the cytokinin labeling observed in transfer RNA. The distributions of the 14C-2-mevalonic acid label and cytokinin activity in tobacco callus transfer RNA fractionated by benzoylated diethylaminoethylcellulose chromatography indicate that at least two cytokinin-containing transfer RNA species are present in this tissue. PMID:16659180

  11. Aggregates of Small Nuclear Ribonucleic Acids (snRNAs) in Alzheimer’s Disease’

    PubMed Central

    Hales, Chadwick M.; Dammer, Eric B.; Diner, Ian; Yi, Hong; Seyfried, Nicholas T.; Gearing, Marla; Glass, Jonathan D.; Montine, Thomas J.; Levey, Allan I.; Lah, James J.

    2014-01-01

    We recently discovered that protein components of the ribonucleic acid (RNA) spliceosome form cytoplasmic aggregates in Alzheimer’s disease (AD) brain, resulting in widespread changes in RNA splicing. However, the involvement of small nuclear RNAs (snRNAs), also key components of the spliceosome complex, in the pathology of AD remains unknown. Using immunohistochemical staining of post-mortem human brain and spinal cord, we identified cytoplasmic tangle-shaped aggregates of snRNA in both sporadic and familial AD cases but not in aged controls or other neurodegenerative disorders. Immunofluorescence using antibodies reactive with the 2,2,7-trimethylguanosine cap of snRNAs and transmission electron microscopy demonstrated snRNA localization with tau and paired helical filaments, the main component of neurofibrillary tangles. Quantitative real-time polymerase chain reaction (PCR) showed U1 snRNA accumulation in the insoluble fraction of AD brains whereas other U snRNAs were not enriched. In combination with our previous results, these findings demonstrate that aggregates of U1 snRNA and U1 small nuclear ribonucleoproteins represent a new pathological hallmark of AD. PMID:24571648

  12. Kinetic models of ribonucleic acid fermentation and continuous culture by Candida tropicalis no.121.

    PubMed

    Li, Bingbing; Chen, Xiaochun; Ren, Huajing; Li, Lei; Xiong, Jian; Bai, Jianxin; Chen, Yong; Wu, Jinglan; Ying, Hanjie

    2012-03-01

    During ribonucleic acid fermentation, the fermentative processes were researched at pH controlled at 4.0 and under natural conditions. Unstructured models in a 50-L airlift fermentor were established for batch RNA production at pH 4.0 using the Verhulst equation for microbial growth, the Luedeking-Piret equation for product formation and a Luedeking-Piret-like equation for substrate uptake. Parameters of the kinetic models were determined using origin 7.5. Based on the models estimated above, another batch fermentation experiment was conducted in a 300-L airlift fermentor, which demonstrated that the models could be useful for RNA production on an industrial scale. Additionally, continuous fermentation based on kinetic models was proposed to make full use of substrates and reduce the cost of waste water treatment. As a result, although the DCW and RNA concentration were 11.5 and 1.68 g L(-1), which were lower than that of batch fermentation, the sugar utilization increased by 14.3%, while the waste water decreased by more than 90%. PMID:21853330

  13. Ribosomal ribonucleic acid isolated from Salmonella typhimurium: absence of the intact 23S species.

    PubMed Central

    Winkler, M E

    1979-01-01

    Ribonucleic acid (RNA) isolated by four distinct methods and from a variety of Salmonella typhimurium strains lacked intact 23S ribosomal RNA (rRNA). On sucrose gradients which minimize aggregation, the vast majority of S. typhimurium rRNA sedimented as a 16S peak with a 14S shoulder. RNA from this region of the gradient was resolved into three discrete bands by electrophoresis in formamide. Two very minor S. typhimurium RNA peaks were resolved at 21S and 10S on sucrose gradients, and each peak formed discrete bands in electrophoresis. It is concluded that if S. typhimurium does possess an intact 23S rRNA species, this species is extremely "labile." The absence of isolatable S. typhimurium 23S rRNA possibly reflected in vivo processing of the rRNA before isolation. Under certain conditions, S. typhimurium rRNA formed discrete aggregates which sedimented similarly to intact Escherichia coli 23S rRNA. Images PMID:383696

  14. Evaluating the reproducibility of quantifying modified nucleosides from ribonucleic acids by LC-UV-MS.

    PubMed

    Russell, Susan P; Limbach, Patrick A

    2013-04-01

    Post-transcriptional chemical covalent modification of adenosine, guanosine, uridine and cytidine occurs frequently in all types of ribonucleic acids (RNAs). In ribosomal RNA (rRNA) and transfer RNA (tRNA) these modifications make important contributions to RNA structure and stability and to the accuracy and efficiency of protein translation. The functional dynamics, synergistic nature and regulatory roles of these posttranscriptional nucleoside modifications within the cell are not well characterized. These modifications are present at very low levels and isolation of individual nucleosides for analysis requires a complex multi-step approach. The focus of this study is to characterize the reproducibility of a liquid chromatography method used to isolate and quantitatively characterize modified nucleosides in tRNA and rRNA when nucleoside detection is performed using ultraviolet and mass spectrometric detection (UV and MS, respectively). Despite the analytical challenges of sample isolation and dynamic range, quantitative profiling of modified nucleosides obtained from bacterial tRNAs and rRNAs is feasible at relative standard deviations of 5% RSD or less. PMID:23500350

  15. Retinoic acid stimulates interstitial collagenase messenger ribonucleic acid in osteosarcoma cells

    NASA Technical Reports Server (NTRS)

    Connolly, T. J.; Clohisy, J. C.; Shilt, J. S.; Bergman, K. D.; Partridge, N. C.; Quinn, C. O.

    1994-01-01

    The rat osteoblastic osteosarcoma cell line UMR 106-01 secretes interstitial collagenase in response to retinoic acid (RA). The present study demonstrates by Northern blot analysis that RA causes an increase in collagenase messenger RNA (mRNA) at 6 h, which is maximal at 24 h (20.5 times basal) and declines toward basal level by 72 h. This stimulation is dose dependent, with a maximal response at 5 x 10(-7) M RA. Nuclear run-on assays show a greater than 20-fold increase in the rate of collagenase mRNA transcription between 12-24 h after RA treatment. Cycloheximide blocks RA stimulation of collagenase mRNA, demonstrating the need for de novo protein synthesis. RA not only causes an increase in collagenase secretion, but is known to decrease collagen synthesis in UMR 106-01 cells. In this study, the increase in collagenase mRNA is accompanied by a concomitant decrease in the level of alpha 1(I) procollagen mRNA, which is maximal at 24 h (70% decrease), with a return to near-control levels by 72 h. Nuclear run-on assays demonstrated that the decrease in alpha 1 (I) procollagen expression does not have a statistically significant transcriptional component. RA did not statistically decrease the stability of alpha 1 (I) procollagen mRNA (calculated t1/2 = 8.06 +/- 0.30 and 9.01 +/- 0.62 h in the presence and absence of RA, respectively). However, transcription and stability together probably contribute to the major decrease in stable alpha 1 (I) procollagen mRNA observed. Cycloheximide treatment inhibits basal level alpha 1 (I) procollagen mRNA accumulation, demonstrating the need for on-going protein synthesis to maintain basal expression of this gene.

  16. A Rapid Technique for the Estimation of Polynucleotide Adenylyltransferase and Ribonucleic Acid Polymerase in Plant Tissues 1

    PubMed Central

    Walter, Trevor J.; Mans, Rusty J.

    1975-01-01

    Nucleic acid-dependent polynucleotide adenylytransferase (EC 2.7.7.19) and ribonucleic acid polymerase (EC 2.7.7.6) have been partially purified from maize tissues (Zea mays L.) utilizing ammonium sulfate precipitation and batch diethylaminoethylcellulose chromatography. The technique is applicable to the simultaneous processing of up to eight samples of plant tissue and affords a rapid and reproducible means of assaying these two enzymes from small quantities of kernels or seedlings. The kinetic characteristics of the partially purified enzymes resemble those from more extensively purified preparations. PMID:16659402

  17. The developmental transcriptome landscape of bovine skeletal muscle defined by Ribo-Zero ribonucleic acid sequencing.

    PubMed

    Sun, X; Li, M; Sun, Y; Cai, H; Li, R; Wei, X; Lan, X; Huang, Y; Lei, C; Chen, H

    2015-12-01

    Ribonucleic acid sequencing (RNA-Seq) libraries are normally prepared with oligo(dT) selection of poly(A)+ mRNA, but it depends on intact total RNA samples. Recent studies have described Ribo-Zero technology, a novel method that can capture both poly(A)+ and poly(A)- transcripts from intact or fragmented RNA samples. We report here the first application of Ribo-Zero RNA-Seq for the analysis of the bovine embryonic, neonatal, and adult skeletal muscle whole transcriptome at an unprecedented depth. Overall, 19,893 genes were found to be expressed, with a high correlation of expression levels between the calf and the adult. Hundreds of genes were found to be highly expressed in the embryo and decreased at least 10-fold after birth, indicating their potential roles in embryonic muscle development. In addition, we present for the first time the analysis of global transcript isoform discovery in bovine skeletal muscle and identified 36,694 transcript isoforms. Transcriptomic data were also analyzed to unravel sequence variations; 185,036 putative SNP and 12,428 putative short insertions-deletions (InDel) were detected. Specifically, many stop-gain, stop-loss, and frameshift mutations were identified that probably change the relative protein production and sequentially affect the gene function. Notably, the numbers of stage-specific transcripts, alternative splicing events, SNP, and InDel were greater in the embryo than in the calf and the adult, suggesting that gene expression is most active in the embryo. The resulting view of the transcriptome at a single-base resolution greatly enhances the comprehensive transcript catalog and uncovers the global trends in gene expression during bovine skeletal muscle development. PMID:26641174

  18. Ribonucleic acid synthesis in normal and immune macrophages after antigenic stimulus.

    PubMed

    Soderberg, L S; Tewari, R P; Solotorovsky, M

    1976-06-01

    Macrophage ribonucleic acid (RNA) synthesis is an important metabolic process intimately related to the function of these cells. Mouse peritoneal macrophage RNA was extracted with phenol in the presence of bentonite and electrophoresed on composite agarose-polyacrylamide gels. The pulse-chase technique was used to follow the precursor relationships in macrophage ribosomal RNA (rRNA) maturation. The rRNA species at 18S and 28S appeared at 15 and 45 min, respectively, after RNA synthesis was halted. Their appearance corresponded closely to decreases in the rRNA precursors at 45S, 36S, and 34S. Studies of RNA methylation aided in confirming the identity of these ribosomal species. Unmethylated RNA species appeared as messenger RNA between 5S and 15S, and at about 55S probably represented heterodisperse nuclear RNA. When normal macrophages were incubated with heat-killed Salmonella enteritidis, an acceleration in the maturation of RNA was observed. The accelerated maturation was indicated by the earlier appearance of 28S rRNA and the more rapid development of an equilibrium state, where further labeling did not change the RNA profile. In macrophage RNA from mice immunized with S. enteritidis, rRNA species appeared rapidly but did not accumulate to the same extent as observed for normal macrophages. Precursor rRNA and other RNA species developed as usual, suggesting specific degradation of mature rRNA. Such rRNA wastage could indicate a mechanism controlling ribosome assembly in the non-proliferating activated macrophage. The pattern of RNA synthesis in immune macrophages was essentially unchanged by the presence of heat-killed S. enteritidis in vitro. PMID:971940

  19. Mining featured micro ribonucleic acids associated with lung cancer based on bioinformatics

    PubMed Central

    Su, Lin; Li, Na; Huo, Xueyun

    2015-01-01

    Background Few genetic markers useful for the screening of lung cancer risk exist. Although related research has shown that certain expression profiles of micro ribonucleic acids (miRNAs) are different in lung cancer versus the normal lung, such as miR-29a and miR-29s, the precise molecular mechanism of lung cancer remains obscure. In order to get a better understanding of the pathogenetic mechanism of lung cancer, we analyzed the differentially expressed genes (DEGs) and identified featured miRNAs in lung cancer tissues. Methods We used the gene expression profile GSE10072, including 49 gene chips of non-tumor tissues and 58 gene chips of lung tumor specimens. The DEGs between these two groups were identified by Limma package in R language. The TarBase database was used to construct the networks of miRNA regulating DEGs related to lung cancer. After ordering miRNAs regulating DEGs, we further screened featured miRNAs combined with the miR2Disease database. Results A total of 5572 DEGs were obtained between lung cancer and control specimens. After constructing a miRNA regulatory network, a total of 398 regulations between 57 miRNAs and 321 target genes existed. By intergrating the miR2Disease database and using a sorting algorithm, a total of six featured miRNAs related to lung cancer were identified, including miR-520h, miR-133a, miR-34, miR-103, miR-370, and miR-148. They might be involved in lung cancer progression by regulating ABCG2, PKM2, VAMP2, GPD1, MAP3K8, and DNMT3B, respectively. Conclusion The top 10 significant miRNAs, such as miR-520h, miR-133a, miR-34, and miR-103 may be potential therapeutic targets for lung cancer. PMID:26273407

  20. Gibberellic Acid-induced Phase Change in Hedera helix as Studied by Deoxyribonucleic Acid-Ribonucleic Acid Hybridization 1

    PubMed Central

    Rogler, Charles E.; Dahmus, Michael E.

    1974-01-01

    Applications of gibberellic acid to the mature form of Hedera helix induce morphological reversions to the juvenile form of growth. The juvenile forms produced are stable with time and differ dramatically from the mature in phenotype. DNA-RNA hybridization techniques have been used to study the RNA populations of juvenile, mature and gibberellic acid-treated mature apices. Hybridization competition experiments using RNA extracted by a hot phenol technique and uniformly labeled in vitro with 3H dimethylsulfate show no qualitative differences between the species of RNA present in juvenile and mature apices. However, differences are observed in the frequency distribution of RNA species using both uniformly labeled or pulse-labeled RNA as a reference. RNA extracted from gibberellic acid-treated mature buds was a less effective competitor than control mature RNA and the difference observed was comparable to that observed between mature and juvenile RNA. These results indicate that at least part of the molecular basis of phase change and gibberellic acid action may involve an alteration in the rate of transcription of certain genes in the apices of the mature form. RNA extracted using the hot phenol procedure contained a fraction of rapidly labeled RNA which was not extractable with cold phenol. When RNA extracted only with cold phenol was used in competition experiments sequences unique to the juvenile were detected and sequences unique to the mature were not detected. Implications of these results in relation to possible post-transcriptional control mechanisms are discussed. PMID:16658844

  1. Identification by affinity chromatography of the eukaryotic ribosomal proteins that bind to 5.8 S ribosomal ribonucleic acid.

    PubMed

    Ulbrich, N; Lin, A; Wool, I G

    1979-09-10

    The proteins that bind to rat liver 5.8 S ribosomal ribonucleic acid were identified by affinity chromatography. The nucleic acid was oxidized with periodate and coupled by its 3'-terminus to Sepharose 4B through and adipic acid dihydrazide spacer. The ribosomal proteins that associate with the immobilized 5.8 S rRNA were identified by polyacrylamide gel electrophoresiss: they were L19, L8, and L6 from the 60 S subunit; and S13 and S9 from the small subparticle. Small amounts of L14, L17', L18, L27/L27', and L35', and of S11, S15, S23/S24, and S26 also were bound to the affinity column, but whether they associate directly and specifically with 5.8 S rRNA is not known. Escherichia coli ribosomal proteins did not bind to the rat liver 5.8 S rRNA affinity column. PMID:468846

  2. Inhibition of Peptidoglycan, Ribonucleic Acid, and Protein Synthesis in Tolerant Strains of Streptococcus mutans

    PubMed Central

    Mychajlonka, Myron; McDowell, Thomas D.; Shockman, Gerald D.

    1980-01-01

    Exposure of exponentially growing cultures of Streptococcus mutans strains FA-1 and GS-5 to various concentrations of benzylpenicillin (Pen G) resulted in inhibition of turbidity increases at low concentrations (0.02 to 0.04 μg/ml). However, in contrast to some other streptococcal species, growth inhibition was not accompanied by cellular lysis or by a rapid loss of viability. In both strains, synthesis of insoluble cell wall peptidoglycan was very sensitive to Pen G inhibition and responded in a dose-dependent manner to concentrations of about 0.2 and 0.5 μg/ml for strains GS-5 and FA-1, respectively. Higher Pen G concentrations failed to inhibit further either growth or insoluble peptidoglycan assembly. Somewhat surprisingly, Pen G also inhibited both ribonucleic acid (RNA) and protein syntheses, each in a dose-dependent manner. Compared with inhibition of peptidoglycan synthesis, inhibition of RNA and protein syntheses by Pen G was less rapid and less extensive. Maximum amounts of radiolabeled Pen G were specifically bound to intact cells upon exposure to about 0.2 and 0.5 μg/ml of Pen G for strains GS-5 and FA-1, respectively, concentrations consistent with those that resulted in maximum or near-maximum inhibitions of the synthesis of cellular peptidoglycan, RNA, and protein. Five polypeptide bands that had a very high affinity for [14C]Pen G were detected in a crude cell envelope preparation of strain FA-1. After exposure of cultures of strain FA-1 to the effects of saturating concentrations of the drug for up to 3 h, addition of penicillinase was followed by recovery of growth after a lag. The length of the lag before regrowth depended on both Pen G concentration and time of exposure. On the basis of these and other observations, it is proposed that the secondary inhibitions of cellular RNA or protein synthesis, or both, are involved in the tolerance of these organisms to lysis and killing by Pen G and other inhibitors of insoluble peptidoglycan assembly

  3. Boletus edulis ribonucleic acid - a potent apoptosis inducer in human colon adenocarcinoma cells.

    PubMed

    Lemieszek, Marta Kinga; Ribeiro, Miguel; Guichard Alves, Helena; Marques, Guilhermina; Nunes, Fernando Milheiro; Rzeski, Wojciech

    2016-07-13

    Despite the large popularity of the Boletus edulis mushroom, little is known about its influence on human health and the possibilities of its therapeutic use. Nevertheless, several reports revealed the usefulness of biopolymers isolated from it in cancer treatment. Our previous studies have shown that B. edulis water soluble biopolymers are not toxic against normal colon epithelial cells (CCD841 CoTr) and at the same concentration range elicited a very prominent antiproliferative effect in colon cancer cells (LS180) which was accompanied with cell cycle arrest in the G0/G1 phase. The purpose of the present study was to verify the proapoptotic properties of a selected fraction from B. edulis - BE3, as well as determine its chemical nature. The BE3 fraction was extracted with hot water and purified by anion-exchange chromatography. Further chemical examinations revealed that BE3 consists mainly of ribonucleic acid (59.1%). The ability of BE3 to induce programmed cell death was examined in human colon cancer cell lines LS180 and HT-29 by measuring caspase activation, DNA fragmentation and expression of BAX, BCL2, TP53 and CDKN1A genes. The sensitivity of colon cancer cells with silenced BAX, TP53 and CDKN1A expression to BE3 treatment was also evaluated. We have demonstrated for the first time that the BE3 fraction is a potent apoptosis inducer in human colon cancer cells. The revealed mechanism of apoptosis triggering was dependent on the presence of functional p53 and consequently was a little different in investigated cell lines. Our results indicated that BE3 stimulated proapoptotic genes BAX (LS180, HT-29), TP53 (LS180) and CDKN1A (HT-29) while at the same time silenced the expression of the key prosurvival gene BCL2 (LS180, HT-29). The obtained results indicate the high therapeutic potential of the BE3 fraction against colon cancer, yet it is necessary to further confirm fraction efficacy and safety in animal and clinical studies. PMID:27302173

  4. Tn9 and IS1 inserts in a ribosomal ribonucleic acid operon of Escherichia coli are incompletely polar.

    PubMed Central

    Brewster, J M; Morgan, E A

    1981-01-01

    Transcription is known to be coupled to translation in many or all bacterial operons which code for proteins. In these operons, nonsense codons which prevent normal translation often result in premature termination of transcription (polarity). However, efficient transcription of ribosomal ribonucleic acid operons (rrn operons) occurs, although rrn transcripts are not translated. It therefore seemed possible that insertion sequences and transposable elements which are polar in protein-coding operons might not be polar in rrn operons. Previously, it has been shown (E. A. Morgan, Cell 21:257-265, 1980) that Tn10 is incompletely polar in the rrnX operon. Here we show that the transposon Tn9 and the insertion sequence IS1 also incompletely polar in rrnX. In normal cells expression of sequences distal to the insertions can be detected by genetic methods. In ultraviolet-irradiated cells expression of distal sequences is about 80% of that observed in uninterrupted rrnX operons. These observations provide evidence that ribonucleic acid polymerase molecules beginning at rrnX promoters can read through Tn9 and IS1 and that, at least in ultraviolet-irradiated cells, read-through is very efficient. Images PMID:6171559

  5. Advanced nuclear magnetic resonance lanthanide probe analyses of short-range conformational interrelations controlling ribonucleic acid structures.

    PubMed

    Yokoyama, S; Inagaki, F; Miyazawa, T

    1981-05-12

    An advanced method was developed for lanthanide-probe analyses of the conformations of flexible biomolecules such as nucleotides. The new method is to determine structure parameters (such as internal-rotation angles) and population parameters for local conformational equilibria of flexible sites, together with standard deviations of these parameters. As the prominent advantage of this method, the interrelations among local conformations of flexible sites may be quantitatively elucidated from the experimental data of lanthanide-induced shifts and relaxations and vicinal coupling constants. As a structural unit of ribonucleic acids, the molecular conformations and conformational equilibria of uridine 3'-monophosphate in aqueous solution were analyzed. The stable local conformers about the C3'-O3' bond are the G+ (phi' = 281 +/- 11 degrees) and G- (phi' = 211 +/- 8 degrees) forms. The internal rotation about the C3'-O3' bond and the ribose-ring puckering are interrelated; 97 +/- 5% of the C3'-endo ribose ring is associated with the G- form while 70 +/- 22% o the C2'-endo ribose ring is associated with the G+ form. An interdependency also exists between the internal rotation about the C4'-C5' bond and the ribose-ring puckering. These short-range conformational interrelations are probably important in controlling the dynamic aspects of ribonucleic acid structures. PMID:6166319

  6. Terminal sequence studies of high-molecular-weight ribonucleic acid. The 3′-termini of rabbit globin messenger ribonucleic acid

    PubMed Central

    Hunt, John A.

    1973-01-01

    Haemoglobin mRNA isolated from EDTA-treated polyribosomes has an apparent molecular weight of 120000–180000 estimated by condensation with 3H-labelled isoniazid after periodate oxidation. Analysis of the ribonuclease digests of isoniazid-labelled RNA by paper electrophoresis and column chromatography enables the amount of contaminating 18S, 7S, 5S and 4S RNA to be estimated, and a corrected molecular weight of globin mRNA as the acid is 161000 or 500 nucleotides in length. This molecule contains two groups of 3′-terminal sequences in equal yield; G-Y-A6 and G-Y-A7 in the ratio 3:2, and G-N9–16-Y-A2 and G-N9–16-Y-N3 in the ratio 3:2. The significance of these sequences is discussed in relation to the poly(A) content of globin mRNA, the specificity of the sequences, and possible function in processing and biosynthesis of mRNA. PMID:4737318

  7. Ribonuclease "XlaI," an activity from Xenopus laevis oocytes that excises intervening sequences from yeast transfer ribonucleic acid precursors.

    PubMed Central

    Otsuka, A; de Paolis, A; Tocchini-Valentini, G P

    1981-01-01

    A ribonuclease (RNase) activity, RNase "XlaI," responsible for the excision of intervening sequences from two yeast transfer ribonucleic acid (tRNA) precursors, pre-tRNA(Tyr) and pre-tRNA(3Leu), has been purified 54-fold from nuclear extracts of Xenopus laevis oocytes. The RNase preparation is essentially free of contaminating RNase. A quantitative assay for RNase XlaI was developed, and the reaction products were characterized. RNase XlaI cleavage sites in the yeast tRNA precursors were identical to those made by yeast extracts (including 3'-phosphate and 5'-hydroxyl termini). Cleavage of pre-tRNA(3Leu) by RNase XlaI and subsequent ligation of the half-tRNA molecules do not require removal of the 5' leader or 3' trailer sequences. Images PMID:6765601

  8. 5S ribosomal ribonucleic acid sequences in Bacteroides and Fusobacterium: evolutionary relationships within these genera and among eubacteria in general

    NASA Technical Reports Server (NTRS)

    Van den Eynde, H.; De Baere, R.; Shah, H. N.; Gharbia, S. E.; Fox, G. E.; Michalik, J.; Van de Peer, Y.; De Wachter, R.

    1989-01-01

    The 5S ribosomal ribonucleic acid (rRNA) sequences were determined for Bacteroides fragilis, Bacteroides thetaiotaomicron, Bacteroides capillosus, Bacteroides veroralis, Porphyromonas gingivalis, Anaerorhabdus furcosus, Fusobacterium nucleatum, Fusobacterium mortiferum, and Fusobacterium varium. A dendrogram constructed by a clustering algorithm from these sequences, which were aligned with all other hitherto known eubacterial 5S rRNA sequences, showed differences as well as similarities with respect to results derived from 16S rRNA analyses. In the 5S rRNA dendrogram, Bacteroides clustered together with Cytophaga and Fusobacterium, as in 16S rRNA analyses. Intraphylum relationships deduced from 5S rRNAs suggested that Bacteroides is specifically related to Cytophaga rather than to Fusobacterium, as was suggested by 16S rRNA analyses. Previous taxonomic considerations concerning the genus Bacteroides, based on biochemical and physiological data, were confirmed by the 5S rRNA sequence analysis.

  9. Properties and substrate specificities of the phenylalanyl-transfer-ribonucleic acid synthetases of Aesculus species

    PubMed Central

    Anderson, J. W.; Fowden, L.

    1970-01-01

    1. Phenylalanyl-tRNA synthetases have been partially purified from cotyledons of seeds of Aesculus californica, which contains 2-amino-4-methylhex-4-enoic acid, and from four other species of Aesculus that do not contain this amino acid. The A. californica preparation was free from other aminoacyl-tRNA synthetases, and the contaminating synthetase activity in preparations from A. hippocastanum was decreased to acceptable limits by conducting assays of pyrophosphate exchange activity in 0.5m-potassium chloride. 2. The phenylalanyl-tRNA synthetase from each species activated 2-amino-4-methylhex-4-enoic acid with Km 30–40 times that for phenylalanine. The maximum velocity for 2-amino-4-methylhex-4-enoic acid was only 30% of that for phenylalanine with the A. californica enzyme, but the maximum velocities for the two substrates were identical for the other four species. 3. 2-Amino-4-methylhex-4-enoic acid was not found in the protein of A. californica, so discrimination against this amino acid probably occurs in the step of transfer to tRNA, though subcellular localization, or subsequent steps of protein synthesis could be involved. 4. Crotylglycine, methallylglycine, ethallylglycine, 2-aminohex-4,5-dienoic acid, 2-amino-5-methylhex-4-enoic acid, 2-amino-4-methylhex-4-enoic acid, β-(thien-2-yl)alanine, β-(pyrazol-1-yl)alanine, phenylserine and m-fluorophenylalanine were substrates for pyrophosphate exchange catalysed by the phenylalanyl-tRNA synthetases of A. californica or A. hippocastanum. Allylglycine, phenylglycine and 2-amino-4-phenylbutyric acid were inactive. PMID:5493504

  10. Impact of size, secondary structure, and counterions on the binding of small ribonucleic acids to layered double hydroxide nanoparticles.

    PubMed

    Rodriguez, Blanca V; Pescador, Jorge; Pollok, Nicole; Beall, Gary W; Maeder, Corina; Lewis, L Kevin

    2015-01-01

    Use of ribonucleic acid (RNA) interference to regulate protein expression has become an important research topic and gene therapy tool, and therefore, finding suitable vehicles for delivery of small RNAs into cells is of crucial importance. Layered double metal hydroxides such as hydrotalcite (HT) have shown great promise as nonviral vectors for transport of deoxyribose nucleic acid (DNA), proteins, and drugs into cells, but the adsorption of RNAs to these materials has been little explored. In this study, the binding of small RNAs with different lengths and levels of secondary structure to HT nanoparticles has been analyzed and compared to results obtained with small DNAs in concurrent experiments. Initial experiments established the spectrophotometric properties of HT in aqueous solutions and determined that HT particles could be readily sedimented with near 100% efficiencies. Use of RNA+HT cosedimentation experiments as well as electrophoretic mobility shift assays demonstrated strong adsorption of RNA 25mers to HT, with twofold greater binding of single-stranded RNAs relative to double-stranded molecules. Strong affinities were also observed with ssRNA and dsRNA 54mers and with more complex transfer RNA molecules. Competition binding and RNA displacement experiments indicated that RNA-HT associations were strong and were only modestly affected by the presence of high concentrations of inorganic anions. PMID:26620852

  11. A versatile method for the removal of melanin from ribonucleic acids in melanocytic cells.

    PubMed

    Satyamoorthy, K; Li, G; Van Belle, P A; Elder, D E; Herlyn, M

    2002-10-01

    Melanin pigments often co-purify during preparation of nucleic acids from cells or tissues of melanocytic origin. Contaminating melanin can severely impede subsequent analyses of RNA. We attempted to eliminate melanin in RNA preparations using selected gel matrices. We show here that co-purified melanin pigments can be largely eliminated from RNA samples after passing through polyacrylamide-based beads (Bio-Gel P-60). After isolation from the pigment-containing cells or tissues, RNA was subsequently processed through batch or column purification under acidic pH conditions. The resulting RNA was devoid of contaminating melanin pigments and amenable to molecular reactions such as polymerase chain reaction and cDNA synthesis by reverse transcriptase. Although the process results in some loss of input RNA, this purification procedure is simple, robust and can easily be adopted in any laboratory for the molecular analysis of RNA that requires removal of melanin contamination. PMID:12394186

  12. Detection of hepatitis C virus ribonucleic acid in the serum by amplification with polymerase chain reaction.

    PubMed Central

    Kato, N; Yokosuka, O; Omata, M; Hosoda, K; Ohto, M

    1990-01-01

    Hepatitis C virus (HCV) RNA was detected in the sera of patients with non-A, non-B chronic liver disease by polymerase chain reaction (PCR). RNA was extracted from the serum, reverse transcribed to cDNA, and amplified by PCR. With this method, 30 patients with non-A, non-B chronic liver disease and 10 healthy subjects were tested. HCV RNA was detected in 13 of 16 (81%) anti-HCV-positive patients and also in 7 of 14 (50%) anti-HCV-negative patients, but in none of 10 anti-HCV-negative healthy subjects. Specificity of this method was confirmed by direct sequencing of amplified cDNA segment. The nucleotide sequences (37 nucleotides) obtained from 15 patients showed only 68-78% homology compared with the prototype HCV nucleotide sequence. In addition, of 15 nucleotide sequences, there were 12 different types. But the translated amino acid sequences (12 amino acids) showed 83-100% homology compared with the prototype HCV amino acid sequence. These data suggest the majority of anti-HCV-positive patients are carriers of HCV. But to detect all the viremic patients, the anti-HCV antibody testing may be insufficient. Direct detection of HCV RNA may be useful in the study of virus replication and its association with various liver diseases. Images PMID:2173727

  13. Gradient enhanced-fluidity liquid hydrophilic interaction chromatography of ribonucleic acid nucleosides and nucleotides: A "green" technique.

    PubMed

    Beilke, Michael C; Beres, Martin J; Olesik, Susan V

    2016-03-01

    A "green" hydrophilic interaction liquid chromatography (HILIC) technique for separating the components of mixtures with a broad range of polarities is illustrated using enhanced-fluidity liquid mobile phases. Enhanced-fluidity liquid chromatography (EFLC) involves the addition of liquid CO2 to conventional liquid mobile phases. Decreased mobile phase viscosity and increased analyte diffusivity results when a liquefied gas is dissolved in common liquid mobile phases. The impact of CO2 addition to a methanol:water (MeOH:H2O) mobile phase was studied to optimize HILIC gradient conditions. For the first time a fast separation of 16 ribonucleic acid (RNA) nucleosides/nucleotides was achieved (16min) with greater than 1.3 resolution for all analyte pairs. By using a gradient, the analysis time was reduced by over 100% compared to similar separations conducted under isocratic conditions. The optimal separation using MeOH:H2O:CO2 mobile phases was compared to MeOH:H2O and acetonitrile:water (ACN:H2O) mobile phases. Based on chromatographic performance parameters (efficiency, resolution and speed of analysis) and an assessment of the environmental impact of the mobile phase mixtures, MeOH:H2O:CO2 mixtures are preferred over ACN:H2O or MeOH:H2O mobile phases for the separation of mixtures of RNA nucleosides and nucleotides. PMID:26860052

  14. Synthesis of Capsid and Noncapsid Viral Proteins in Response to Encephalomyocarditis Virus Ribonucleic Acid in Animal Cell-Free Systems

    PubMed Central

    Dobos, P.; Kerr, Ian M.; Martin, E. M.

    1971-01-01

    The polypeptide products formed in two cell-free protein-synthetic systems programmed with encephalomyocarditis (EMC) virus ribonucleic acid (RNA) have been compared with the virus-specific proteins found in EMC-infected cells and with the capsid proteins of the purified virion. Tryptic peptides of 35S-methioninelabeled proteins from these three sources were compared by co-chromatography and electrophoresis and by isoelectric focussing. Fifty-two methionine-containing peptides were resolved in digests of material from infected cells, of which about one-third were also clearly present in digests of the virion capsid proteins. The product formed in response to EMC RNA in cell-free systems from Krebs mouse ascites tumor cells yielded 26 to 29 such peptides. Most of these peptides were shown to behave identically with virus-specific peptides from infected cells, whereas just under half of them appeared to be identical with peptides from the virion capsid proteins. The product formed in response to EMC RNA in the L-cell cell-free system was similar, whereas six additional EMC-specific peptides were detected in mixed Krebs L-cell systems. The results indicate that the EMC RNA genome is partially translated in the mouse cell-free systems used to yield products containing both virion capsid and virus-specific noncapsid polypeptides. Images PMID:4331652

  15. Polymeric Cryogel-Based Boronate Affinity Chromatography for Separation of Ribonucleic Acid from Bacterial Extracts.

    PubMed

    Shakya, Akhilesh Kumar; Srivastava, Akshay; Kumar, Ashok

    2015-01-01

    Three-dimensional monolithic columns are preferred stationary phase in column chromatography. Conventional columns based on silica or particles are efficient in bioseparation though associated with limitations of nonspecific interaction and uneven porosity that causes high mass transfer resistance for the movement of big molecules. Cryogels as a monolith column have shown promising application in bioseparation. Cryogels column can be synthesized in the form of a monolith at sub-zero temperature through gelation of pre-synthesized polymers or polymerization of monomers. Cryogels are macroporous and mechanically stable materials. They have open interconnected micron-sized pores with a wide range of porosity (10-200 μm). Current protocol demonstrated the ability of poly(hydroxymethyl methacrylate)-co-vinylphenyl boronic acid p(HEMA-co-VPBA) cryogel matrix for selective separation of RNA from the bacterial crude extract. PMID:26623972

  16. Derepression of Synthesis of the Aminoacyl-Transfer Ribonucleic Acid Synthetases for the Branched-Chain Amino Acids of Escherichia coli

    PubMed Central

    McGinnis, Etheleen; Williams, Ann C.; Williams, L. S.

    1974-01-01

    The kinetics of derepression of valyl-, isoleucyl-, and leucyl-transfer ribonucleic acid (tRNA) synthetase formation was examined during valine-, isoleucine-, and leucine-limited growth. When valine was limiting growth, valyl-tRNA synthetase formation was maximally derepressed within 5 min, whereas the rates of synthesis of isoleucyl-, and leucyl-tRNA synthetases were unchanged. Isoleucine-restricted growth caused a maximal derepression of isoleucyl-tRNA synthetase formation in 5 min and derepression of valyl-tRNA synthetase formation in 15 min with no effect on leucyl-tRNA synthetase formation. When leucine was limiting growth, leucyl-tRNA synthetase formation was immediately derepressed, whereas valyl- and isoleucyl-tRNA synthetase formation was unaffected by manipulation of the leucine supply to the cells. These results support our previous findings that valyl-tRNA synthetase formation is subject to multivalent repression control by both isoleucine and valine. In contrast, repression control of iso-leucyl- and leucyl-tRNA synthetase formation is specifically mediated by the supply of the cognate amino acid. PMID:4604302

  17. Effects of starvation for potassium and other inorganic ions on protein degradation and ribonucleic acid synthesis in Escherichia coli.

    PubMed

    St John, A C; Goldberg, A L

    1980-09-01

    Starvation of Escherichia coli for potassium, phosphate, or magnesium ions leads to a reversible increase in the rate of protein degradation and an inhibition of ribonucleic acid (RNA) synthesis. In cells deprived of potassium, the breakdown of the more stable cell proteins increased two- to threefold, whereas the hydrolysis of short-lived proteins, both normal ones and analog-containing polypeptides, did not change. The mechanisms initiating the enhancement of proteolysis during starvation for these ions were examined. Upon starvation for amino acids or amino acyl-transfer RNA (tRNA), protein breakdown increases in relA+ (but not relA) cells as a result of the rapid synthesis of guanosine-5'-diphosphate-3'-diphosphate (ppGpp). However, a lack of amino acyl-tRNA does not appear to be responsible for the increased protein breakdown in cells starved for inorganic ions, since protein breakdown increased in the absence of these ions in both relA+ and relA cultures, and since a large excess of amino acids did not affect this response. In bacteria in which energy production is restricted, ppGpp levels also rise, and protein breakdown increases. The ion-deprived cultures did show a 40 to 75% reduction in adenosine-5'-triphosphate levels,l similar to that seen upon glucose starvation. However, this decrease in ATP content does not appear to cause the increase in protein breakdown or lead to an accumulation of ppGpp. No consistent change in intracellular ppGpp levels was found in relA+ or relA cells starved for these ions. In addition, in relX mutants, removal of these ions led to accelerated protein degradation even though relX cells are unable to increase ppGpp levels or proteolysis when deprived of a carbon source. In the potassium-, phosphate-, and magnesium-deprived cultures, the addition of choramphenicol or tetracycline caused a reduction in protein breakdown toward basal levels. Such findings, however, do not indicate that protein synthesis is essential for the

  18. Contemporaneous isolation of deoxyribonucleic acid-dependent ribonucleic acid polymerase and poly(A) polymerase from rat liver mitochondria.

    PubMed Central

    Gallerani, R; di Istituto; Istituto di, Ch; Saccone, C

    1976-01-01

    1. Poly(A) polymerase and DNA-dependent RNA polymerase from rat liver mitochondria can be completely separated by using two different chromatographic procedures. 2. Poly(A) polymerase can only incorporate ATP into acid-insoluble material and strongly depends on the addition of an endogenous factor (probably containing a mixture of oligoribonucleotides), but it is not stimulated by DNA. 3. RNA polymerase is fully DNA-dependent and rifampicin-sensitive, but was not stimulated by the endogenous factor mentioned above. 4. The chromatographic behaviour of the two enzymes, together with the properties described, suggest that they represent two different protein molecules. PMID:962867

  19. Isolation and Partial Characterization of Temperature-Sensitive Escherichia coli Mutants with Altered Leucyl- and Seryl-Transfer Ribonucleic Acid Synthetases

    PubMed Central

    Low, B.; Gates, F.; Goldstein, T.; Söll, D.

    1971-01-01

    Two temperature-sensitive mutants of Escherichia coli have been found in which the conditional growth is a result of a thermosensitive leucyl-transfer ribonucleic acid (tRNA) synthetase and seryl-tRNA synthetase, respectively. The corresponding genetic loci, leuS and serS, cotransduce with lip and serC, respectively. As a result of the mutationally altered leucyl-tRNA synthetase, some leucine-, valine-, and isoleucine-forming enzymes were derepressed. Thus, leucyl-tRNA synthetase is involved in the repression of the enzymes needed for the synthesis of branched-chain amino acids. PMID:4942762

  20. Chloramphenicol-induced changes in the synthesis of ribosomal, transfer, and messenger ribonucleic acids in Escherichia coli B/r.

    PubMed

    Shen, V; Bremer, H

    1977-06-01

    The synthesis of ribosomal ribonucleic acid (rRNA), transfer RNA (tRNA) and messenger RNA (mRNA) was measured in Escherichia coli B/r after the addition of 100 mug of chloramphenicol (CAM) per ml to cultures growing either in one of three minimal media (succinate, glycerol, or glucose) or in one of the same three media supplemented with 20 amino acids. (i) During CAM treatment, rRNA and tRNA were synthesized in the same relative proportions (85:15) as during exponential growth. The faster accumulation of tRNA relative to rRNA in CAM was due to a decreased stability of rRNA that is synthesized in the presence of or immediately before the addition of CAM. (ii) CAM stimulated the synthesis of rRNA and tRNA two- to eightfold. The results fell into two groups; one group was from studies done in minimal media and the other was from amino acid-supplemented media. In each group the stimulation decreased with increasing growth rate of the culture during exponential growth before the addition of CAM; however, the stimulation in minimal media was lower than that in amino acid-supplemented media. (iii) CAM caused an increase in the proportion of rRNA and tRNA synthesis and a corresponding decrease in the proportion of mRNA synthesis. In minimal media, the residual proportion of mRNA synthesis after CAM treatment was 10 to 15% of total RNA synthesis; in amino acid-supplemented media this proportion was 0 to 10%. In either case, the residual proportion of mRNA synthesis was independent of the proportions observed during exponential growth in these media. (iv) The absolute rate of mRNA synthesis decreased severalfold with the addition of CAM; i.e., the rate of synthesis of rRNA and tRNA was increased at the expense of mRNA synthesis. (v) During exponential growth, the fraction of the instantaneous rate of total RNA synthesis that corresponds to mRNA is a function of both the growth rate and the presence or absence of amino acids in the growth medium: in the absence of amino acids

  1. Co-ordination between membrane phospholipid synthesis and accelerated biosynthesis of cytoplasmic ribonucleic acid and protein

    PubMed Central

    Tata, J. R.

    1970-01-01

    1. The rate of synthesis of membrane phospholipid was studied in rat liver and seminal vesicles by following the incorporation of [32P]orthophosphate, [14C]choline and [14C]glycerol. Particular emphasis was laid on the endoplasmic reticulum, which was fractionated into smooth microsomal membranes, heavy rough membranes, light rough membranes and free polyribosomes. 2. Phospholipid labelling patterns suggested a heterogeneity in the synthesis and turnover of the different lipid moieties of smooth and rough endoplasmic membranes. The major phospholipids, phosphatidylcholine and phosphatidylethanolamine, were labelled relatively rapidly with 32P over a short period of time whereas incorporation of radioisotope into the minor phospholipids, sphingomyelin, lysolecithin and phosphatidylinositol proceeded slowly but over a longer period of time. 3. The incorporation of orotic acid into RNA and labelled amino acids into protein of the four submicrosomal fractions was also studied. 4. Rapid growth of the liver was induced by the administration of growth hormone and tri-iodothyronine to hypophysectomized and thyroidectomized rats and by partial hepatectomy. Growth of seminal vesicles of castrated rats was stimulated with testosterone propionate. 5. The rate of labelling of membrane phospholipids was enhanced in all major subcellular particulate fractions (nuclear, mitochondrial and microsomal) during induced growth. However, it was in the rough endoplasmic reticulum that the accumulation of phospholipids, RNA and protein was most marked. The effect of hormone administration was also to accelerate preferentially the labelling with 32P of sphingomyelin relative to that of phosphatidylcholine or phosphatidylethanolamine. 6. Time-course analyses showed that, in all four growth systems studied, the enhancement of the rate of membrane phospholipid synthesis coincided with the rather abrupt increase in the synthesis of RNA and protein of the rough endoplasmic reticulum. Growth

  2. Primary structure of a sperm cell anion exchanger and its messenger ribonucleic acid expression during spermatogenesis.

    PubMed

    Holappa, K; Mustonen, M; Parvinen, M; Vihko, P; Rajaniemi, H; Kellokumpu, S

    1999-10-01

    Chloride/bicarbonate (Cl-/HCO(3)-) exchangers are a family of proteins (anion exchanger [AE] gene family) that regulate many vital cellular processes such as intracellular pH, cell volume, and Cl- concentration. They may also be involved in the regulation of sperm cell motility and acrosome reaction during fertilization, as these two phenomena are bicarbonate dependent, and we have previously shown that a polypeptide immunologically related to erythrocyte band 3 is expressed in mammalian sperm cells. We have now identified this putative sperm cell anion exchanger as the AE2 isoform of this gene family. First, we determined its complete primary structure from the human testis lambda gt 11 cDNA library. The cloned sequence was found to consist of 3896 base pairs (bp) with an open reading frame of 3726 bp, and to be almost identical to the previously published human genomic AE2 sequence. Only four amino acid disparities were found between these two sequences. Second, our in situ hybridization analyses showed that AE2 mRNA is expressed in developing sperm cells, indicating that the cloned sequence corresponds to the sperm cell AE. Our reverse transcription-polymerase chain reaction analyses suggested further that the expression of AE2 mRNA was variable to some extent during the epithelial cell cycle. Strongest expression was observed at stages VII-XIV except for stage X, i.e., when major structural and morphological changes take place. These results suggest that the full-length AE2 isoform regulates HCO(3)- transport in mature sperm cells and thus their motility in vivo. PMID:10491633

  3. Prolactin messenger ribonucleic acid levels, prolactin synthesis, and radioimmunoassayable prolactin during the estrous cycle in the Golden Syrian hamster

    SciTech Connect

    Massa, J.S. ); Blask, D.E. )

    1990-01-01

    The purpose of this study was to observe the molecular dynamics of pituitary prolactin (PRL) gene expression during the estrous cycle of the Golden Syrian hamster. PRL messenger ribonucleic acid (mRNA) levels, PRL synthesis were measured in the morning on each day of the cycle. We observed that all of these PRL indices declined or did not change from Day 2 to Day 3 of the cycle. From Day 3 to Day 4 however, PRL mRNA levels increased 33-38% and media {sup 3}H-PRL increased 32-42%, while there were no significant changes in pituitary {sup 3}H-PRL, or RIA-PRL in the media or pituitary. From Day 4 to Day 1 (estrus) there was reciprocal change in the levels of {sup 3}H-PRL in the pituitary vs. the media, with the former increasing 37-50% and the latter decreasing 25-32%. Pituitary RIA-PRL did also increased 45-64% from Day 4 to Day 1 while media RIA-PRL did not change. These data are consistent with the following hypothesis: On the morning of proestrus(Day 4) in the hamster, PRL mRNA levels are elevated compared to those on Day 3, signaling an increase in PRL synthesis. This newly synthesized PRL is shunted into a readily releasable pool on the morning of Day 4 (contributing to the afternoon surge of serum PRL), and into a preferentially stored pool by the morning of Day 1.

  4. Precursor ribosomal ribonucleic acid and ribosome accumulation in vivo during the recovery of Salmonella typhimurium from thermal injury.

    PubMed

    Tomlins, R I; Ordal, Z J

    1971-07-01

    When cells of S. typhimurium were heated at 48 C for 30 min in phosphate buffer (pH 6.0), they became sensitive to Levine Eosin Methylene Blue Agar containing 2% NaCl (EMB-NaCl). The inoculation of injured cells into fresh growth medium supported the return of their normal tolerance to EMB-NaCl within 6 hr. The fractionation of ribosomal ribonucleic acid (rRNA) from unheated and heat-injured cells by polyacrylamide gel electrophoresis demonstrated that after injury the 16S RNA species was totally degraded and the 23S RNA was partially degraded. Sucrose gradient analysis demonstrated that after injury the 30S ribosomal subunit was totally destroyed and the sedimentation coefficient of the 50S particle was decreased to 47S. During the recovery of cells from thermal injury, four species of rRNA accumulated which were demonstrated to have the following sedimentation coefficients: 16, 17, 23, and 24S. Under identical recovery conditions, 22, 26, and 28S precursors of the 30S ribosomal subunit and 31 and 48S precursors of the 50S ribosomal subunit accumulated along with both the 30 and 50S mature particles. The addition of chloramphenicol to the recovery medium inhibited both the maturation of 17S RNA and the production of mature 30S ribosomal subunits, but permitted the accumulation of a single 22S precursor particle. Chloramphenicol did not affect either the maturation of 24S RNA or the mechanism of formation of 50S ribosomal subunits during recovery. Very little old ribosomal protein was associated with the new rRNA synthesized during recovery. New ribosomal proteins were synthesized during recovery and they were found associated with the new rRNA in ribosomal particles. The rate-limiting step in the recovery of S. typhimurium from thermal injury was in the maturation of the newly synthesized rRNA. PMID:4935315

  5. Age-related differences in messenger ribonucleic acid expression of key proteins involved in adipose cell differentiation and metabolism.

    PubMed

    Imbeault, P; Vidal, H; Tremblay, A; Vega, N; Nadeau, A; Després, J P; Mauriège, P

    2001-02-01

    This study was performed to compare the expression of key proteins [lipoprotein lipase (LPL), hormone-sensitive lipase (HSL), complement 3 (C3), and peroxisome proliferator-stimulated receptor-gamma (PPAR gamma)] involved in sc abdominal adipose tissue (AT) metabolism of young (n = 13) vs. middle-aged (n = 16) men. The sc abdominal AT-LPL activity as well as fat cell lipolysis were also measured in both groups of men. Young and middle-aged men displayed similar body weight and sc abdominal fat accumulation, measured by computed tomography. However, middle-aged men were characterized by a higher percent body fat (28 +/- 5% vs. 22 +/- 7%; P < 0.05) than young subjects. No difference between groups was observed in sc abdominal adipose tissue LPL activity. On the other hand, maximal lipolytic responses of sc abdominal adipocytes to isoproterenol (beta-adrenergic agonist) or to postadrenoceptor agents such as dibutyryl cAMP, forskolin, and theophylline were lower in middle-aged than in young men (P < 0.05). AT-LPL messenger ribonucleic acid (mRNA) levels were similar regardless of the subject's age. However, HSL, C3, and PPAR gamma mRNA levels were higher in middle-aged than in young individuals (P < 0.01-0.05). After correction for percent body fat, only HSL and C3 mRNA levels remained significantly different between groups (P < 0.05). Taken together, these results suggest that aging has an effect on the up-regulation of HSL and C3 mRNA levels, whereas PPAR gamma expression seems to be related mainly to increased adiposity. PMID:11158053

  6. Studies on the pathogenesis of liver necrosis by α-amanitin. Effect of α-amanitin on ribonucleic acid synthesis and on ribonucleic acid polymerase in mouse liver nuclei

    PubMed Central

    Stirpe, F.; Fiume, L.

    1967-01-01

    1. Injection of α-amanitin to mice causes a decreased incorporation of [6-14C]-orotic acid into liver RNA in vivo. 2. The activity of RNA polymerase activated by Mn2+ and ammonium sulphate is greatly impaired in liver nuclei isolated from mice poisoned with α-amanitin, and is inhibited by the addition of the same toxin in vitro. 3. The activity of the Mg2+-activated RNA polymerase is only slightly affected by α-amanitin either administered to mice or added in vitro. PMID:5584017

  7. Small activating ribonucleic acid reverses tyrosine kinase inhibitor resistance in epidermal growth factor receptor‐mutant lung cancer by increasing the expression of phosphatase and tensin homolog

    PubMed Central

    Li, Meng; Peng, Zhongmin; Ren, Wangang

    2016-01-01

    Background Epidermal growth factor receptor‐tyrosine kinase inhibitors (TKI‐EGFRs) present a new prospect for the treatment of lung cancer. However, in clinical application, the majority of patients become TKI resistant within a year. More and more studies have shown that a loss of phosphatase and tensin homolog (PTEN) expression is associated with TKI resistance. An alternative method of upregulating PTEN expression may reverse TKI resistance. Methods We designed five candidate small activating ribonucleic acids (saRNAs) to target PTEN, and transfected them into H‐157 cells to screen out functional saRNA. We used reverse transcriptase‐polymerase chain reaction and Western blot to evaluate the effect of saRNA to PTEN expression. We then analyzed the growth and apoptosis of cells transfected with saRNA under the treatment of TKI to investigate whether saRNAs can reverse TKI resistance by upregulating PTEN expression. Results The functional saRNA we designed could upregulate PTEN expression. The H‐157 cells transfected with saRNA grew slower in the presence of TKI drugs than the cells that were not transfected with saRNA. The apoptosis rate was also obviously higher. Conclusions Our study proves that loss of PTEN expression is an important mechanism of TKI resistance. It is possible to control TKI resistance by upregulating PTEN expression using RNA activation technology. PMID:27385992

  8. RoboOligo: software for mass spectrometry data to support manual and de novo sequencing of post-transcriptionally modified ribonucleic acids

    PubMed Central

    Sample, Paul J.; Gaston, Kirk W.; Alfonzo, Juan D.; Limbach, Patrick A.

    2015-01-01

    Ribosomal ribonucleic acid (RNA), transfer RNA and other biological or synthetic RNA polymers can contain nucleotides that have been modified by the addition of chemical groups. Traditional Sanger sequencing methods cannot establish the chemical nature and sequence of these modified-nucleotide containing oligomers. Mass spectrometry (MS) has become the conventional approach for determining the nucleotide composition, modification status and sequence of modified RNAs. Modified RNAs are analyzed by MS using collision-induced dissociation tandem mass spectrometry (CID MS/MS), which produces a complex dataset of oligomeric fragments that must be interpreted to identify and place modified nucleosides within the RNA sequence. Here we report the development of RoboOligo, an interactive software program for the robust analysis of data generated by CID MS/MS of RNA oligomers. There are three main functions of RoboOligo: (i) automated de novo sequencing via the local search paradigm. (ii) Manual sequencing with real-time spectrum labeling and cumulative intensity scoring. (iii) A hybrid approach, coined ‘variable sequencing’, which combines the user intuition of manual sequencing with the high-throughput sampling of automated de novo sequencing. PMID:25820423

  9. Synaptic vesicles contain small ribonucleic acids (sRNAs) including transfer RNA fragments (trfRNA) and microRNAs (miRNA)

    PubMed Central

    Li, Huinan; Wu, Cheng; Aramayo, Rodolfo; Sachs, Matthew S.; Harlow, Mark L.

    2015-01-01

    Synaptic vesicles (SVs) are neuronal presynaptic organelles that load and release neurotransmitter at chemical synapses. In addition to classic neurotransmitters, we have found that synaptic vesicles isolated from the electric organ of Torpedo californica, a model cholinergic synapse, contain small ribonucleic acids (sRNAs), primarily the 5′ ends of transfer RNAs (tRNAs) termed tRNA fragments (trfRNAs). To test the evolutionary conservation of SV sRNAs we examined isolated SVs from the mouse central nervous system (CNS). We found abundant levels of sRNAs in mouse SVs, including trfRNAs and micro RNAs (miRNAs) known to be involved in transcriptional and translational regulation. This discovery suggests that, in addition to inducing changes in local dendritic excitability through the release of neurotransmitters, SVs may, through the release of specific trfRNAs and miRNAs, directly regulate local protein synthesis. We believe these findings have broad implications for the study of chemical synaptic transmission. PMID:26446566

  10. The identification by affinity chromatography of the rat liver ribosomal proteins that bind to elongator and initiator transfer ribonucleic acids.

    PubMed

    Ulbrich, N; Wool, I G; Ackerman, E; Sigler, P B

    1980-07-25

    Mixed yeast elongator-tRNAs (bulk tRNA lacking fRNAm,fMet), pure isoaccepting species of elongator-tRNAs (tRNAmMet and tRNAPhe), and purified initiator-tRNA (tRNAfMet) were each oxidized with periodate and the 3' terminus was coupled to Sepharose 4B through an adipic acid dihydrazide spacer. The rat liver ribosomal proteins that associated with the tRNAs were isolated by affinity chromatography and identified by electrophoresis in polyacrylamide gels. The rat liver ribosomal proteins that were bound to the elongator-tRNA preparations were L6, L35a, and S15; small amounts of a number of other proteins also associated with the nucleic acid. When initiator-tRNA (tRNAfMet) was immobilized on Sepharose, only L6 and L35a were bound; no 40 S subunit proteins associated with initiator-tRNA. No Escherichia coli proteins formed a complex with either eukaryotic initiator- or elongator-tRNAs. PMID:7391064

  11. Initiation of Protein Synthesis by Folate-Sufficient and Folate-Deficient Streptococcus faecalis R: Partial Purification and Properties of Methionyl-Transfer Ribonucleic Acid Synthetase and Methionyl-Transfer Ribonucleic Acid Formyltransferase

    PubMed Central

    Samuel, Charles E.; Rabinowitz, Jesse C.

    1974-01-01

    RNAfMet are competitive inhibitors of both plus- and minus-folate S. faecalis formyltransferase; folic acid, pteroic acid, aminopterin, and Met-tRNAmMet are not inhibitory. These results indicate that the presence or absence of folic acid in the culture medium of S. faecalis has no apparent effect on either methionyl-tRNA synthetase or methionyl-tRNA formyltransferase, the two enzymes directly involved in the formation of formylmethionyl-tRNAfMet. Therefóre, the lack of N-formylation of Met-tRNAfMet in minus-folate S. faecalis is due to the absence of the formyl donor, a 10-formyl-tetrahydropteroyl derivative. Although the general properties of S. faecalis methionyl-tRNA synthetase are similar to those of other aminoacyl-tRNA synthetases, S. faecalis methionyl-tRNA formyltransferase differs from other previously described transformylases in certain kinetic parameters. PMID:4206871

  12. Changes in hepatic lipid parameters and hepatic messenger ribonucleic acid expression following estradiol administration in laying hens (Gallus domesticus).

    PubMed

    Lee, B K; Kim, J S; Ahn, H J; Hwang, J H; Kim, J M; Lee, H T; An, B K; Kang, C W

    2010-12-01

    Fatty liver hemorrhagic syndrome (FLHS) is characterized by increased hepatic triacylglycerol content associated with liver hemorrhages and results in a sudden decline in egg production. Genetic, environmental, nutritional, and hormonal factors have all been implicated in the etiology of FLHS, but the exact cause of FLHS is still unknown. Estrogens have been implicated in the development of excess fat content of the liver and in the etiology of FLHS. This study investigated estradiol (E(2)) administration in hens and its effect on lipid metabolism. Hy-Line Brown laying hens were intramuscularly injected with E(2) on a daily basis for 3 wk. The dosages were 0, 0.5, and 1.0 mg/kg of BW, with corn oil injections used as a control. Egg production and quality were measured among the groups, with no significant difference seen in egg production. Liver weights of hens treated with E(2) were greater than those of control hens, but the increase was not statistically significant. Serum glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase activities and E(2) plasma concentrations increased in a dose-dependent manner, with plasma concentration of E(2) increasing from 6,900 to 19,000 pg/mL. No significant differences in free cholesterol or phospholipids were observed, but there was a significant increase in hepatic triacylglycerol levels. Injection with E(2) showed an increased expression of mRNA for peroxisome proliferator-activated receptor γ (23-fold), but not for peroxisome proliferator-activated receptor α. A statistically significant increase was seen for fatty acid synthase, apolipoprotein B, and adenosine triphosphate citrate lyase, but not for acetyl coenzyme A carboxylase, apolipoprotein VLDL-II, microsomal triglyceride transport protein, or malic enzyme. For proteins involved in the oxidation of E(2), only cytochrome P450 3A37 showed a statistically significant increase. The present results suggest that E(2) upregulates the synthesis of fatty acids

  13. Impairment of the catalytic activity of Escherichia coli ribonucleic acid polymerase by a unique reaction of 4-chloro-7-nitrobenzofurazan.

    PubMed Central

    Bratcher, S C; Nitta, K; Kronman, M J

    1979-01-01

    Escherichia coli RNA polymerase loses 55-65% of its catalytic activity on reaction with Nbf-Cl (4-choro-7-nitrobenzofurazan). This partial inactivation was shown to be the result of specific impairment of RNA-chain elongation, since initiation of RNA chains was not altered after treatment with Nbf-Cl. The site of reaction was shown to be a unique thiol on the beta-subunit. This thiol is not accessible to reaction with 5,5'-dithiobis-(2-nitrobenzoic acid). No protection of the enzyme against reaction with Nbf-Cl could be obtained with the inhibitor rifamycin nor with calf thymus DNA, GTP or 1,10-phenanthroline, indicating that the unique thiol is probably not within the active site. The specific impairment of RNA-chain elongation thus appears to be the result of a local conformational change which leaves chain initiation unimpaired. Changes observed in the tryptophan fluorescence spectrum of the enzyme or reaction with Nbf-Cl are consistent with formation of a Meisenheimer complex of the reagent with a nucleophilic group on the enzyme near the reactive thiol. It is proposed that formation of such a complex and a subsequent conformational change renders this thiol unusually susceptible to reaction with Nbf-Cl. PMID:393251

  14. Effects of gamma-irradiation on biosynthesis of different types of ribonucleic acids in normal and regenerating rat liver.

    PubMed Central

    Markov, G G; Dessev, G N; Russev, G C; Tsanev, R G

    1975-01-01

    1. The effect of gamma-irradiation (4000rd) on the synthesis of ribosomal (pre-rRNA) and heterogeneous nuclear RNA (pre-mRNA) in normal and in regenerating rat liver was studied by using 40 min labelling with [6(-14)C]orotic acid. 2. Partial hepatectomy caused a sharp transient increase in the specific radioactivity of the endogenous low-molecular-weight RNA precursors in the livers of both normal and irradiated rats. Irradiation of intact animals did not affect the pool. 3. Irradiation enhanced the synthesis of pre-rRNA for at least 12h. The synthesis of pre-mRNA was also enhanced, but only in the first 3h after irradiation. 4. Partial hepatectomy strongly stimulated the synthesis of both pre-rRNA and pre-mRNA. 5. The synthesis of pre-rRNA was enhanced also in regenerating liver of animals irradiated before or after the operation. The conclusion can be drawn that the early increase in the synthesis of ribosomal RNA is a non-specific cellular response to different injuring factors. 6. The only case where irradiation caused an early inhibition of RNA synthesis was that of pre-mRNA in regenerating liver. This supports the hypothesis that ionizing radiation does not suppress the transcription per se but affects the mechanisms of activation of new genes (cellular programming). PMID:1147904

  15. Changes in the patterns of synthesis of ribonucleic acid species in immature rat uterus in response to oestradiol-17β

    PubMed Central

    Billing, R. J.; Barbiroli, B.; Smellie, R. M. S.

    1969-01-01

    1. After treatment of immature rats with diethylstilboestrol, the wet weight and RNA content of uterine tissue increased rapidly, reaching a peak at 40hr. After an initial lag of a few hours, the acid-soluble ribose and protein contents also rose to maxima at 40hr. No increase in DNA content occurred until at least 24hr. after treatment. 2. The RNA from immature rat uterus isolated at various times up to 6hr. after administration of oestradiol-17β was labelled by injecting [3H]uridine and [3H]guanosine intraperitoneally 30min. before the animals were killed. It was fractionated on columns of kieselguhr coated with methylated serum albumin and the radioactivity in fractions corresponding to transfer RNA, 7s RNA, ribosomal RNA, Q1-RNA, Q2-RNA and DNA-like RNA was determined. 3. The radioactivity of the whole RNA increased steadily for 6hr. after hormone treatment. The earliest changes occurred in the Q1-RNA (ribosomal RNA precursor), whereas at longer time-intervals the radioactivity of the ribosomal RNA, 7s RNA and transfer RNA increased by four- to five-fold. The radioactivity of the DNA-like RNA increased by about 50%, but only at the longer time-intervals. 4. It is concluded that one of the earliest changes in response to oestradiol treatment is a major increase in synthesis of ribosomal RNA followed later by a similar increase in synthesis of transfer RNA and by a much smaller increase in synthesis of DNA-like RNA. The change in synthesis of ribosomal RNA in immature rat uterus may represent one of the most important responses to oestradiol treatment. PMID:4309670

  16. Temporal sequence of events during the initiation process in Escherichia coli deoxyribonucleic acid replication: roles of the dnaA and dnaC gene products and ribonucleic acid polymerase.

    PubMed Central

    Zyskind, J W; Deen, L T; Smith, D W

    1977-01-01

    Three thermosensitive deoxyribonucleic acid (DNA) initiation mutants of Escherichia coli exposed to the restrictive temperature for one to two generations were examined for the ability to reinitiate DNA replication after returning to the permissive temperature in the presence of rifampin, chloramphenicol, or nalidixic acid. Reinitiation in the dnaA mutant was inhibited by rifampin but not by chloramphenicol, whereas renitiation was not inhibited by rifampin but not by chloramphenicol, whereas reinitiation was not inhibited in two dnaC mutants by either rifampin or chloramphenicol. To observe the rifampin inhibition, the antibiotic must be added at least 10 min before return to the permissive temperature. The rifampin inhibition of reinitiation was not observed when a rifampin-resistant ribonucleic acid ((RNA) polymerase gene was introduced into the dnaA mutant, demonstrating that RNA polymerase synthesizes one or more RNA species required for the initation of DNA replication (origin-RNA). Reinitiation at 30 degrees C was not inhibited by streptolydigin in a stretolydigin-sensitive dnaA muntant. Incubation in the presence of nalidixic acid prevented subsequent reinitiation in the dnaC28 mutant but did not inhibit reinitiation in the dnaA5 muntant. These results demonstrate that the dnaA gene product acts before or during the synthesis of an origin-RNA, RNA polymerase synthesizes this origin RNA, and the dnaC gene product is involved in a step after this RNA synthesis event. Furthermore, these results suggest that the dnaC gene product is involved in the first deoxyribounucleotide polymerization event wheareas the dnaA gene product acts prior to this event. A model is presented describing the temporal sequence of events that occur during initiation of a round of DNA replication, based on results in this and the accompanying paper. PMID:321429

  17. Molecular cloning of otoconin-22 complementary deoxyribonucleic acid in the bullfrog endolymphatic sac: effect of calcitonin on otoconin-22 messenger ribonucleic acid levels.

    PubMed

    Yaoi, Yuichi; Suzuki, Masakazu; Tomura, Hideaki; Sasayama, Yuichi; Kikuyama, Sakae; Tanaka, Shigeyasu

    2003-08-01

    Anuran amphibians have a special organ called the endolymphatic sac (ELS), containing many calcium carbonate crystals, which is believed to have a calcium storage function. The major protein of aragonitic otoconia, otoconin-22, which is considered to be involved in the formation of calcium carbonate crystals, has been purified from the saccule of the Xenopus inner ear. In this study, we cloned a cDNA encoding otoconin-22 from the cDNA library constructed for the paravertebral lime sac (PVLS) of the bullfrog, Rana catesbeiana, and sequenced it. The bullfrog otoconin-22 encoded a protein consisting of 147 amino acids, including a signal peptide of 20 amino acids. The protein had cysteine residues identical in a number and position to those conserved among the secretory phospholipase A(2) family. The mRNA of bullfrog otoconin-22 was expressed in the ELS, including the PVLS and inner ear. This study also revealed the presence of calcitonin receptor-like protein in the ELS, with the putative seven-transmembrane domains of the G protein-coupled receptors. The ultimobranchialectomy induced a prominent decrease in the otoconin-22 mRNA levels of the bullfrog PVLS. Supplementation of the ultimobranchialectomized bullfrogs with synthetic salmon calcitonin elicited a significant increase in the mRNA levels of the sac. These findings suggest that calcitonin secreted from the ultimobranchial gland, regulates expression of bullfrog otoconin-22 mRNA via calcitonin receptor-like protein on the ELS, thereby stimulating the formation of calcium carbonate crystals in the lumen of the ELS. PMID:12865304

  18. Two novel PRPF31 premessenger ribonucleic acid processing factor 31 homolog mutations including a complex insertion-deletion identified in Chinese families with retinitis pigmentosa

    PubMed Central

    Dong, Bing; Chen, Jieqiong; Zhang, Xiaohui; Pan, Zhe; Bai, Fengge

    2013-01-01

    Objective To identify the causative mutations in two Chinese families with retinitis pigmentosa (RP), and to describe the associated phenotype. Methods Individuals from two unrelated families underwent full ophthalmic examinations. After informed consent was obtained, genomic DNA was extracted from the venous blood of all participants. Linkage analysis was performed on the known genetic loci for autosomal dominant retinitis pigmentosa with a panel of polymorphic markers in the two families, and then all coding exons of the PRP31 premessenger ribonucleic acid processing factor 31 homolog (PRPF31) gene were screened for mutations with direct sequencing of PCR-amplified DNA fragments. Allele-specific PCR was used to validate a substitution in all available family members and 100 normal controls. A large deletion was detected with real-time quantitative PCR (RQ-PCR) using a panel of primers from regions around the PRPF31 gene. Long-range PCR, followed by DNA sequencing, was used to define the breakpoints. Results Clinical examination and pedigree analysis revealed two four-generation families (RP24 and RP106) with autosomal dominant retinitis pigmentosa. A significant two-point linkage odd disequilibrium score was generated at marker D19S926 (Zmax=3.55, θ=0) for family RP24 and D19S571 (Zmax=3.21, θ=0) for family RP106, and further linkage and haplotype studies confined the disease locus to chromosome 19q13.42 where the PRPF31 gene is located. Mutation screening of the PRPF31 gene revealed a novel deletion c.1215delG (p.G405fs+7X) in family RP106. The deletion cosegregated with the family’s disease phenotype, but was not found in 100 normal controls. No disease-causing mutation was detected in family RP24 with PCR-based sequencing analysis. RQ-PCR and long-range PCR analysis revealed a complex insertion-deletion (indel) in the patients of family RP24. The deletion is more than 19 kb and encompasses part of the PRPF31 gene (exons 1–3), together with three adjacent

  19. A comparison of cell-free placental messenger ribonucleic acid and color Doppler ultrasound for the prediction of placental invasion in patients with placenta accreta

    PubMed Central

    Naghshineh, Elham; Khorvash, Elahe; Kamali, Sara

    2015-01-01

    Background: The aim of the present study was to comparison between cell-free placental messenger ribonucleic acid (mRNA) and Doppler ultrasound for the prediction of placental invasion in women with placenta accreta. Materials and Methods: In this cross-sectional study, 50 pregnant women at risk for placenta accreta underwent color Doppler and assessment of cell-free placental mRNA. Real-time reverse-transcription polymerase chain reaction was used for measurement of cell-free placental mRNA in maternal plasma. Based on the findings at cesarean delivery and histological examination, patients were divided into two groups of women with and without placenta accrete. To compare of the mean of mRNA levels between the two groups we used independent t-test and to compare of the mean of age and gestational age at sonography we used Mann-Whitney test. For determination of sensitivity and specificity and the cut-off point of mRNA levels we used the receiver operating characteristic curve. Results: A total of 50 women with a mean age of 30.24 ± 4.905 years entered the study and 12 (24%) patients were diagnosed with placenta accreta. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of Doppler ultrasound were 83.3%, 78.9%, 56% and 94%, respectively. Results of our study showed if we consider a cut-off point equal to 3.325, with sensitivity and specificity of 0.917 and 0.789, respectively and the sensitivity, specificity, PPV and NPV of mRNA with were cut-off point of 3.325 were 91.7%, 78.9%, 57.9% and 96.8%, respectively. Conclusions: Cell-free mRNA is an acceptable, easy made, functional test with sensitivity, specificity, PPV and NPV more than Doppler ultrasound for diagnosis and prediction of incidence of placenta accrete and we recommend the use of cell-free mRNA test for diagnosis of placenta accreta. PMID:25709996

  20. Identification of N-terminal methionine in the precursor of immunoglobulin light chain. Initiation of translation of messenger ribonucleic acid in plants and animals.

    PubMed Central

    Schechter, I; Burstein, Y

    1976-01-01

    The proteins programmed in the wheat-germ cell-free system by the mRNA coding for the MOPC-321 mouse myeloma L (light) chain were labelled with [35S]methionine, [4,5-3H]leucine or [3-3H]serine, and were subjected to amino acid-sequence analyses. Over 95% of the total cell-free product was sequenced as one homogeneous protein, which corresponds to the precursor of the L-chain protein. In the precursor, 20 amino acid residues precede the N-terminus of the mature protein. This extra piece contains one methionine residue at the N-terminus, one serine residue at position 18, and six leucine residues, which are clustered in two triplets at positions 6, 7, 8 and 11, 12, 13. The identification of methionine at the N-terminus of the precursor is in agreement with the evidence showing that unblocked methionine is the initiator residue for protein synthesis in eukaryotes. The absence of methionine at position 20, which precedes the N-terminal residue of the mature protein, suggests that myeloma cells synthesize the precursor. However, within the cell the precursor should be rapidly processed to the mature L chain, since precursor molecules have not yet been found in the intact animal. The abundance (30%) of leucine residues indicates that the extra-piece moiety is quite hydrophobic. The extra piece of the MOPC-321 L-chain precursor synthesized with the aid of the Krebs II ascites cell-free system is of identical size and it has the same leucine sequence [Schechter et al. (1975) Science 188, 160-162]. This indicates that cell-free systems derived from the plant and animal kingdom initiate mRNA translation from the same point. It is shown that the amino acid sequence of minute amounts of a highly labelled protein (0.1 pmol) can be faithfully determined in the presence of a large excess (over 2000 000-fold) of unrelated non-radioactive proteins. Images PLATE 2 PLATE 1 PMID:821467

  1. Properties of the ribonucleic acid bacteriophage ZIK/1 coat protein and its synthesis in an Escherichia coli cell-free system

    PubMed Central

    Robinson, J. W.

    1972-01-01

    The coat protein subunit of the RNA bacteriophage ZIK/1 has a molecular weight of 12100 and does not contain histidine, methionine and cysteine. The amino acid composition of the coat protein is different from that of other RNA bacteriophage coat proteins. Bacteriophage ZIK/1 belongs to a class of RNA bacteriophages distinct from the f2 type, which lack histidine in their coat proteins, and the Qβ type, which lack histidine and methionine. Bacteriophage ZIK/1 RNA is an efficient template in the Escherichia coli cell-free system producing coat protein as the major product and a number of non-coat proteins. This result is similar to that obtained with RNA from f2-type bacteriophages. It is probable that the genomes of RNA bacteriophages are structurally similar and that differences between the types of RNA bacteriophage arise from minor differences in RNA sequence. PMID:4564257

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

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

  3. Competing addition and hydrolysis of the cytidylylcytidylyladenosine terminal residues of transfer ribonucleic acid isolated from the non-lactating bovine mammary gland

    PubMed Central

    Herrington, M. D.; Hawtrey, A. O.

    1970-01-01

    1. The enzyme fraction obtained from the pH5 enzyme of non-lactating bovine mammary gland between 40 and 100% ammonium sulphate saturation markedly inhibited the AMP-incorporating activity of rat liver nucleotide-incorporating enzyme. This inhibitory effect has been attributed to high nuclease activity which can be partially removed by adsorption of the enzyme fraction on to calcium phosphate gel. 2. The degradation action of the calcium phosphate-purified enzyme is confined mainly to the terminal trinucleotide sequence -pCpCpA of tRNA, its effect being analogous to that of venom phosphodiesterase. This enzyme is heat labile and very readily loses its degradative activity. 3. Treatment of the enzyme fraction with Macaloid results in complete removal of the phosphodiesterase, leaving an enzyme capable of incorporating AMP into tRNA. 4. Transfer RNA extracted from non-lactating bovine mammary gland in the presence of polyvinyl sulphate and Macaloid is able to accept amino acids with an efficiency 30% of that shown by lactating bovine mammary-gland tRNA isolated under identical conditions. PMID:4321270

  4. Down-regulation of messenger ribonucleic acid encoding an importer of sulfoconjugated steroids during human chorionic gonadotropin-induced follicular luteinization in vivo.

    PubMed

    Brown, Kristy A; Bouchard, Nadine; Lussier, Jacques G; Sirois, Jean

    2007-01-01

    Members of the organic anion transporting polypeptide (SLCO/OATP) superfamily are capable of importing anionic compounds across the lipid bilayer in a sodium-independent manner. Member 2B1 has been shown to transport few substrates, two of which are dihydroepiandrosterone-3-sulfate (DHEA-S) and estrone-3-sulfate. Steroid sulfatase (STS) catalyses the hydrolysis of these steroids into their unconjugated counterparts. The objective of this study was to investigate the regulation of SLCO2B1 and STS mRNAs during human chorionic gonadotropin (hCG)-induced ovulation/luteinization. The equine SLCO2B1 cDNA was cloned and shown to encode a 709-amino acid protein (OATP2B1) that is highly conserved when compared to mammalian orthologs. RT-PCR/Southern blot analyses were performed to study the regulation of SLCO2B1 and STS transcripts in equine preovulatory follicles isolated between 0 and 39h after hCG treatment. Results showed high levels of SLCO2B1 mRNA expression before hCG, with a marked decrease observed in follicles obtained 24-39h post-hCG (P<0.05). Analyses of isolated granulosa and theca interna cells identified high mRNA expression in both cell types prior to hCG treatment, with granulosa cells showing a more rapid SLCO2B1 mRNA down-regulation. No significant change in STS mRNA was observed in intact follicle walls. However, when both cell types were isolated, a significant decrease in STS mRNA was observed in granulosa cells 24-39h post-hCG. Collectively, these results demonstrate that the hCG-dependent induction of follicular luteinization is accompanied by the down-regulation of SLCO2B1 and STS transcripts. Considering that OATP2B1 can import sulfoconjugated DHEA and estrogens, and that STS can remove the sulfonate moiety from these steroids, their down-regulation in luteinizing preovulatory follicles may provide an additional biochemical basis for the decrease in ovarian 17beta-estradiol biosynthesis after the LH surge. PMID:17049229

  5. The theory of the deoxyribonucleic acid - ribonucleic acid hybridization reaction.

    PubMed Central

    Thomou, H; Katsanos, N A

    1976-01-01

    A general equation is derived describing data of DNA-RNA hybridization in the presence of a competing self-annealing reaction of RNA. The well known double-reciprocal relation and the Scatchard equation are shown to be limiting cases of this general equation. Some new hybridization data at various temperatures are presented and analysed by using the new equation. The results can only be explained if we assume that the behavior of DNA towards single RNA molecules is the same as that towards the annealed form, (RNA12. The variation of the equilibrium constant of the hybridization reaction with temperature is small, indicating a small heat of reaction. The maximum amount of hybridized RNA at equilibrium appears to be independent of temperature. PMID:1275887

  6. Amino acids

    MedlinePlus

    Amino acids are organic compounds that combine to form proteins . Amino acids and proteins are the building blocks of life. When proteins are digested or broken down, amino acids are left. The human body uses amino acids ...

  7. Folic Acid

    MedlinePlus

    Folic acid is a B vitamin. It helps the body make healthy new cells. Everyone needs folic acid. For women who may get pregnant, it is really important. Getting enough folic acid before and during pregnancy can prevent major birth ...

  8. Folic Acid

    MedlinePlus

    Folic acid is used to treat or prevent folic acid deficiency. It is a B-complex vitamin needed by ... Folic acid comes in tablets. It usually is taken once a day. Follow the directions on your prescription label ...

  9. Aspartic acid

    MedlinePlus

    ... also called asparaginic acid. Aspartic acid helps every cell in the body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources of aspartic acid include: Legumes such as ...

  10. Androgen biosynthesis in the stomach: expression of cytochrome P450 17 alpha-hydroxylase/17,20-lyase messenger ribonucleic acid and protein, and metabolism of pregnenolone and progesterone by parietal cells of the rat gastric mucosa.

    PubMed

    Le Goascogne, C; Sananès, N; Eychenne, B; Gouézou, M; Baulieu, E E; Robel, P

    1995-04-01

    Dehydroepiandrosterone (DHEA) and its conjugates persist in the rat brain, for up to 1 month after ablation of both adrenals and gonads. Since DHEA synthesis in brain from pregnenolone (PREG) was excluded, we have considered other tissular sources including the digestive tract. In situ hybridization with specific oligonucleotide probes showed that the parietal cells of the gastric mucosa, contrary to other cell types, strongly expressed P450(17) alpha messenger RNA. Expression of the enzyme in the parietal cells was confirmed by immunocytochemistry with specific antibodies. An intense reaction was observed in the stomach of adult males and of cyclic or pregnant females. Access to food did not influence the intensity of immunostaining. It appeared at postnatal days 16-21, then the number of positive cells increased rapidly and leveled off at adult age. Parietal cells were released by pronase digestion of everted stomachs from adult male and female rats and were purified by density gradient centrifugation on Nycodenz. 5 x 10(4) to 1.6 x 10(6) cells were incubated with either 1 microM 14C-PREG or 14C-progesterone (14C-PROG) at 37 C under 95% O2-5% CO2, for 10-180 min. PREG was converted to 17-OH PREG and to androstenediol, whereas PROG was converted to 17-OH PROG and to testosterone. Only minute amounts of either DHEA or androstenedione, respectively, were detected at any incubation time, indicating their fast conversion to the corresponding 17 beta-hydroxysteroids. 3H-25-OH cholesterol was not metabolized to 3H-PREG, and 14C-PREG was not converted to 14C-PROG, in accordance with negative immunocytochemical results with antibodies to cytochrome P450scc and 3 beta-hydroxysteroid dehydrogenase delta 5-->4-isomerase (3 beta-HSD). In conclusion, the parietal cells, which are known as the source of gastric acid secretion, can synthesize testosterone from PROG and androstenediol from PREG. The physiological relevance of such conversions remains to be established. PMID

  11. Acid Rain.

    ERIC Educational Resources Information Center

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  12. Amino acids

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  13. Mefenamic Acid

    MedlinePlus

    Mefenamic acid is used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Mefenamic acid is in a class of medications called NSAIDs. ...

  14. Aminocaproic Acid

    MedlinePlus

    Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

  15. Ascorbic Acid

    MedlinePlus

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  16. Acid mucopolysaccharides

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003368.htm Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  17. Ethacrynic Acid

    MedlinePlus

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  18. Valproic Acid

    MedlinePlus

    Valproic acid is used alone or with other medications to treat certain types of seizures. Valproic acid is also used to treat mania (episodes of ... to relieve headaches that have already begun. Valproic acid is in a class of medications called anticonvulsants. ...

  19. Fatty acids - trans fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  20. Impact of microfluidic processing on bacterial ribonucleic acid expression

    PubMed Central

    Gandi, Senthil Kumar; Watson, David; Kersaudy-Kerhoas, Maïwenn; Bachmann, Till; Bridle, Helen

    2015-01-01

    Bacterial transcriptomics is widely used to investigate gene regulation, bacterial susceptibility to antibiotics, host-pathogen interactions, and pathogenesis. Transcriptomics is crucially dependent on suitable methods to isolate and detect bacterial RNA. Microfluidics offer ways of creating integrated point-of-care systems, analysing a sample from preparation, and RNA isolation to detection. A critical requirement for on-chip diagnostics to deliver on their promise is that mRNA expression is not altered via microfluidic sample processing. This article investigates the impact of the use of microfluidics upon RNA expression of bacteria isolated from blood, a key step towards proving the suitability of such systems for further development. PMID:26045727

  1. Ribonucleic acid polymerase activities in Jerusalem-artichoke tissue

    PubMed Central

    Gore, John R.; Ingle, John

    1974-01-01

    1. Artichoke tuber tissue contained RNA polymerase activity bound to the chromatin and in the supernatant after chromatin sedimentation. 2. The activity in the supernatant, the soluble polymerase, was fractionated into polymerases I and II by DEAE-cellulose chromatography, and the properties of each activity were determined. 3. The proportions of chromatin-bound and soluble activities varied with growth of the tissue, and there was a correlation between chromatin-bound activity and RNA accumulation. 4. The properties of the solubilized chromatin activity were compared with those of the soluble activity, and the relationship between these two activities is discussed. PMID:4464848

  2. Specific spin-labeling of transfer ribonucleic acid molecules.

    PubMed Central

    Caron, M; Dugas, H

    1976-01-01

    The spin labels anhydride (ASL), bromoacetamide (BSL) and carbodiimide (CSL) were used to label selectively tRNAGlu, tRNA fMet and tRNAPhe from E. coli. The preparation and characterization of the sites of labeling of eight new spin-labeled tRNAs are described. The sites of labeling are: s2U using ASL, BSL and CLS and tRNAGlu; s4U using ASL and BSL on tRNAfMet and tRNAPhe; U-37 with CSL on tRNfMet; U-33 with CSL on tRNAPhe. The rare base X at position 47 of tRNAPhe has been acylated with a spin-labeled N-hydroxysuccinimide (HSL). The 3'end of unfractionated tRNA molecules has been chemically modified to a morpholino spin-labeled analogue (MSL). Their respective e.s.r. spectra are reported and discussed. PMID:175353

  3. The Genes for Cytoplasmic Ribosomal Ribonucleic Acid in Higher Plants

    PubMed Central

    Scott, N. Steele; Ingle, J.

    1973-01-01

    The genes for cytoplasmic ribosomal RNA are partially resolved from the bulk of the DNA by CsCl equilibrium centrifugation. Although in some plants the buoyant density of the ribosomal RNA genes is as expected from the base composition of ribosomal RNA, others show a large discrepancy which cannot be due to the presence of low G-C spacer-DNA. The cross-hybridization observed with 1.3 and 0.7 × 106 molecular weight ribosomal RNAs and DNA, which varies greatly with different plant species, is not due to contamination of the ribosomal RNAs, and is specific for the ribosomal DNA of each species, probably largely restricted to those sequences coding for the two stable ribosomal RNAs. The double reciprocal plot may be used for the extrapolation of saturation values only with caution, because in these cases such plots are not linear over the whole of the hybridization reaction. PMID:16658392

  4. Acid Deposition

    EPA Science Inventory

    This indicator presents acid deposition trends in the contiguous U.S. from 1989 to 2007. Data are broken down by wet and dry deposition and deposition of nitrogen and sulfur compounds. Acid deposition is particularly damaging to lakes, streams, and forests and the plants and a...

  5. Acid rain

    SciTech Connect

    White, J.C. )

    1988-01-01

    This book presents the proceedings of the third annual conference sponsored by the Acid Rain Information Clearinghouse (ARIC). Topics covered include: Legal aspects of the source-receptor relationship: an energy perspective; Scientific uncertainty, agency inaction, and the courts; and Acid rain: the emerging legal framework.

  6. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

    This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

  7. Acid rain

    SciTech Connect

    Sweet, W.

    1980-06-20

    Acid precipitation includes not only rain but also acidified snow, hail and frost, as well as sulfur and nitrogen dust. The principal source of acid precipitation is pollution emitted by power plants and smelters. Sulfur and nitrogen compounds contained in the emissions combine with moisture to form droplets with a high acid content - sometimes as acidic as vinegar. When sufficiently concentrated, these acids can kill fish and damage material structures. Under certain circumstances they may reduce crop and forest yields and cause or aggravate respiratory diseases in humans. During the summer, especially, pollutants tend to collect over the Great Lakes in high pressure systems. Since winds typically are westerly and rotate clockwise around high pressure systems, the pollutants gradually are dispersed throughout the eastern part of the continent.

  8. Asparagusic acid.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2014-01-01

    Asparagusic acid (1,2-dithiolane-4-carboxylic acid) is a simple sulphur-containing 5-membered heterocyclic compound that appears unique to asparagus, though other dithiolane derivatives have been identified in non-food species. This molecule, apparently innocuous toxicologically to man, is the most probable culprit responsible for the curious excretion of odorous urine following asparagus ingestion. The presence of the two adjacent sulphur atoms leads to an enhanced chemical reactivity, endowing it with biological properties including the ability to substitute potentially for α-lipoic acid in α-keto-acid oxidation systems. This brief review collects the scattered data available in the literature concerning asparagusic acid and highlights its properties, intermediary metabolism and exploratory applications. PMID:24099657

  9. [Gastric Acid].

    PubMed

    Ruíz Chávez, R

    1996-01-01

    Gastric acid, a product of parietal cells secretion, full fills multiple biological roles which are absolutely necessary to keep corporal homeostasis. The production of the acid depends upon an effector cellular process represented in the first step by histamine, acetilcholine and gastrin, first messengers of the process. These interact with specific receptors than in sequence activate second messengers -cAMP and the calcium-calmodulin system- which afterwards activate a kinase. An specific protein is then phosphorilated by this enzyme, being the crucial factor that starts the production of acid. Finally, a proton bomb, extrudes the acid towards the gastric lumen. The secretion process mentioned above, is progressive lyactivated in three steps, two of which are stimulators -cephalic and gastric phases- and the other one inhibitor or intestinal phase. These stages are started by mental and neurological phenomena -thought, sight, smell or memory-; by food, drugs or other ingested substances; and by products of digestion. Changes in regulation of acid secretion, in the structure of gastro-duodenal mucosal barrier by a wide spectrum of factors and agents including food, drugs and H. pylori, are the basis of acid-peptic disease, entity in which gastric acid plays a fundamental role. From the therapeutic point of view, so at the theoretical as at the practical levels, t is possible to interfere with the secretion of acid by neutralization of some of the steps of the effector cellular process. An adequate knowledge of the basics related to gastric acid, allows to create strategies for the clinical handling of associated pathology, specifically in relation to peptic acid disease in all of the known clinical forms. PMID:12165790

  10. Acid fog

    SciTech Connect

    Hileman, B.

    1983-03-01

    Fog in areas of southern California previously thought to be pollution-free has been shown to have a pH as low as 1.69. It has been found to be most acidic after smoggy days, suggesting that it forms on the aerosol associated with the previously exiting smog. Studies on Whiteface Mountain in the Adirondacks show that fog water is often 10 times as acidic as rainwater. As a result of their studies, California plans to spend $4 million on acid deposition research in the coming year. (JMT)

  11. Folic acid

    MedlinePlus

    ... in the blood vessel to keep it open. Bipolar disorder. Taking folic acid does not appear to improve the antidepressant effects of lithium in people with bipolar disorder. However, taking folate with the medication valproate improves ...

  12. Mefenamic Acid

    MedlinePlus

    ... as mefenamic acid may cause ulcers, bleeding, or holes in the stomach or intestine. These problems may ... like coffee grounds, blood in the stool, or black and tarry stools.Keep all appointments with your ...

  13. ACID RAIN

    EPA Science Inventory

    Acid precipitation has become one of the major environmental problems of this decade. It is a challenge to scientists throughout the world. Researchers from such diverse disciplines as plant pathology, soil science, bacteriology, meteorology and engineering are investigating diff...

  14. Acid Precipitation

    ERIC Educational Resources Information Center

    Likens, Gene E.

    1976-01-01

    Discusses the fact that the acidity of rain and snow falling on parts of the U.S. and Europe has been rising. The reasons are still not entirely clear and the consequences have yet to be well evaluated. (MLH)

  15. Carnosic acid.

    PubMed

    Birtić, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc

    2015-07-01

    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (∼70 years ago) and its identification (∼50 years ago), numerous articles and patents (∼400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. PMID:25639596

  16. Aminocaproic Acid

    MedlinePlus

    Amicar® Oral Solution ... Aminocaproic acid comes as a tablet and a solution (liquid) to take by mouth. It is usually ... it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away ...

  17. Tranexamic Acid

    MedlinePlus

    ... is used to treat heavy bleeding during the menstrual cycle (monthly periods) in women. Tranexamic acid is in ... tablets for more than 5 days in a menstrual cycle or take more than 6 tablets in a ...

  18. Acidic precipitation

    SciTech Connect

    Martin, H.C.

    1987-01-01

    At the International Symposium on Acidic Precipitation, over 400 papers were presented, and nearly 200 of them are included here. They provide an overview of the present state of the art of acid rain research. The Conference focused on atmospheric science (monitoring, source-receptor relationships), aquatic effects (marine eutrophication, lake acidification, impacts on plant and fish populations), and terrestrial effects (forest decline, soil acidification, etc.).

  19. Salicylic acids

    PubMed Central

    Hayat, Shamsul; Irfan, Mohd; Wani, Arif; Nasser, Alyemeni; Ahmad, Aqil

    2012-01-01

    Salicylic acid is well known phytohormone, emerging recently as a new paradigm of an array of manifestations of growth regulators. The area unleashed yet encompassed the applied agriculture sector to find the roles to strengthen the crops against plethora of abiotic and biotic stresses. The skipped part of integrated picture, however, was the evolutionary insight of salicylic acid to either allow or discard the microbial invasion depending upon various internal factors of two interactants under the prevailing external conditions. The metabolic status that allows the host invasion either as pathogenesis or symbiosis with possible intermediary stages in close systems has been tried to underpin here. PMID:22301975

  20. Folic acid

    MedlinePlus

    ... disease called vitiligo, and an inherited disease called Fragile-X syndrome. It is also used for reducing harmful side ... to blood clots (ischemic stroke). Inherited disease called Fragile-X syndrome.Taking folic acid by mouth does not improve ...

  1. Acid rain

    SciTech Connect

    Not Available

    1984-06-01

    An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

  2. Formic acid

    Integrated Risk Information System (IRIS)

    Formic acid ; CASRN 64 - 18 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  3. Selenious acid

    Integrated Risk Information System (IRIS)

    Selenious acid ; CASRN 7783 - 00 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  4. Benzoic acid

    Integrated Risk Information System (IRIS)

    Benzoic acid ; CASRN 65 - 85 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  5. Trichloroacetic acid

    Integrated Risk Information System (IRIS)

    Trichloroacetic acid ( TCA ) ; CASRN 76 - 03 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonca

  6. Dichloroacetic acid

    Integrated Risk Information System (IRIS)

    Dichloroacetic acid ; CASRN 79 - 43 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  7. Acrylic acid

    Integrated Risk Information System (IRIS)

    Acrylic acid ( CASRN 79 - 10 - 7 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  8. Cacodylic acid

    Integrated Risk Information System (IRIS)

    Cacodylic acid ; CASRN 75 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  9. Phosphoric acid

    Integrated Risk Information System (IRIS)

    Phosphoric acid ; CASRN 7664 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  10. Stearic Acid

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) is presented for the chemical, stearic acid. The profile lists the chemical's physical and harmful characteristics, exposure limits, and symptoms of major exposure, for the benefit of teachers and students, who use the chemical in the laboratory.

  11. Hydroxycarboxylic acids and salts

    DOEpatents

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  12. Methylmalonic acid blood test

    MedlinePlus

    ... acid is a substance produced when proteins, called amino acids, in the body break down. The health care ... Cederbaum S, Berry GT. Inborn errors of carbohydrate, ammonia, amino acid, and organic acid metabolism. In: Gleason CA, Devaskar ...

  13. Folic acid - test

    MedlinePlus

    Folic acid is a type of B vitamin. This article discusses the test to measure the amount of folic acid in the blood. ... that may interfere with test results, including folic acid supplements. Drugs that can decrease folic acid measurements ...

  14. Uric acid urine test

    MedlinePlus

    The uric acid urine test measures the level of uric acid in urine. Uric acid level can also be checked using a blood ... help determine the cause of a high uric acid level in the blood. It may also be ...

  15. Methylmalonic acid blood test

    MedlinePlus

    The methylmalonic acid blood test measures the amount of methylmalonic acid in the blood. ... Methylmalonic acid is a substance produced when proteins, called amino acids, in the body break down. The health care ...

  16. Folic Acid and Pregnancy

    MedlinePlus

    ... 5 Things to Know About Zika & Pregnancy Folic Acid and Pregnancy KidsHealth > For Parents > Folic Acid and ... before conception and during early pregnancy . About Folic Acid Folic acid, sometimes called folate, is a B ...

  17. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  18. New bioactive fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  19. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to new compounds, 7,10-dihydroxy-8(E)-octadecen...

  20. The stability, polyadenylic acid content and ribonucleoprotein form of nulcear ribonucleic acid in artichoke.

    PubMed Central

    Chapman, K S; Ingle, J

    1976-01-01

    A nuclear preparation, containing 60-80% of the total tissue DNA and less than 0.5% of the total rRNA, was used to characterize the nuclear RNA species synthesized in cultured artichoke explants. The half-lives of the nuclear RNA species were estimated from first-order-decay analyses to be: hnRNA (heterogeneous nuclear RNA) containing poly(A), 38 min; hnRNA lacking poly(A), 37 min; 2.5 X 10(6)-mol. wt. precursor rRNA, 24 min; 1.4 X 10(6)-mol.wt. precursor rRNA, 58 min; 1.0 X 10(6)-mol.wt. precursor rRNA, 52 min. The shorter half-lives are probably overestimates, owing to the time required for equilibration of the nucleotide-precursor pools. The pathway of rRNA synthesis is considered in terms of these kinetic measurements. The rate of accumulation of cytoplasmic polydisperse RNA suggested that as much as 40% of the hnRNA may be transported to the cytoplasm. The 14-25% of the hnRNA that contained a poly(A) tract had an average molecular size of 0.7 X 10(6) daltons. The poly(A) segment was 40-200 nucleotides long, consisted of at least 95% AMP and accounted for 8-10% of the [32P]orthophosphate incorporated into the poly(A)-containing hnRNA. Ribonucleoprotein particles released from nuclei by sonication, lysis in EDTA or incubation in buffer were analysed by sedimentation through sucrose gradients and by isopycnic centrifugation in gradients of metrizamide and CsCl. More than 50% of the hnRNA remained bound to the chromatin after each treatment. The hnRNA was always associated with protein but the densities of isolated particles suggested that the ratio of protein to RNA was lower than that reported for mammalian cells, The particles separated from chromatin were not enriched for poly(A)-containing hnRNA. PMID:1008819

  1. Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxygenated fatty acids are useful as specialty chemicals, plasticizers, and biomedicals. Microbial enzymes convert fatty acids to mono-, di-, and trihydroxy fatty acid products. Among them, Bacillus megaterium ALA2 converted n-6 and n-3 PUFAs to many new oxygenated fatty acids. Linoleic acid was ...

  2. Uric acid test (image)

    MedlinePlus

    Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

  3. Amino Acid Metabolism Disorders

    MedlinePlus

    ... defects & other health conditions > Amino acid metabolism disorders Amino acid metabolism disorders E-mail to a friend Please ... baby’s newborn screening may include testing for certain amino acid metabolism disorders. These are rare health conditions that ...

  4. Plasma amino acids

    MedlinePlus

    Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

  5. Stomach acid test

    MedlinePlus

    Gastric acid secretion test ... of the cells in the stomach to release acid. The stomach contents are then removed and analyzed. ... 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour in ...

  6. Azelaic Acid Topical

    MedlinePlus

    Azelaic acid gel is used to clear the bumps, lesions, and swelling caused by rosacea (a skin disease that ... redness, flushing, and pimples on the face). Azelaic acid cream is used to treat acne. Azelaic acid ...

  7. Facts about Folic Acid

    MedlinePlus

    ... Information For... Media Policy Makers Facts About Folic Acid Language: English Español (Spanish) Recommend on Facebook Tweet ... of the baby's brain and spine. About folic acid Folic acid is a B vitamin. Our bodies ...

  8. Acid Lipase Disease

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Acid Lipase Disease Information Page Synonym(s): Cholesterol Ester Storage ... Trials Related NINDS Publications and Information What is Acid Lipase Disease ? Acid lipase disease or deficiency occurs ...

  9. Folic acid - test

    MedlinePlus

    ... folic acid measurements include: Alcohol Aminosalicylic acid Birth control pills Estrogens Tetracyclines Ampicillin Chloramphenicol Erythromycin Methotrexate Penicillin Aminopterin Phenobarbital Phenytoin Drugs to treat malaria

  10. Oxalic acid poisoning

    MedlinePlus

    Symptoms of oxalic acid poisoning include: Abdominal pain Burns and blisters where the acid contacted the skin Collapse Convulsions Mouth pain Shock Throat pain Tremors (unintentional trembling) Vomiting

  11. Acid distribution in phosphoric acid fuel cells

    SciTech Connect

    Okae, I.; Seya, A.; Umemoto, M.

    1996-12-31

    Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

  12. Adenovirus Type 2-Simian Virus 40 Hybrid Population: Evidence for a Hybrid Deoxyribonucleic Acid Molecule and the Absence of Adenovirus-Encapsidated Circular Simian Virus 40 Deoxyribonucleic Acid

    PubMed Central

    Crumpacker, Clyde S.; Levin, Myron J.; Wiese, William H.; Lewis, Andrew M.; Rowe, Wallace P.

    1970-01-01

    The deoxyribonucleic acid (DNA) from the adenovirus-encapsidated particles of the adenovirus type 2 (Ad2)-simian virus 40 (SV40) hybrid population plaque variant (Ad2++ HEY), known to yield SV40 virus with high efficiency, was studied by equilibrium density centrifugation followed by ribonucleic acid-DNA hybridization employing virus-specific complementary ribonucleic acids synthesized in vitro. These techniques establish linkage between the Ad2 and SV40 components in the adenovirus-encapsidated particles of this population. The linkage is alkali-resistant and presumably covalent; thus, the Ad2 DNA and SV40 DNA are present in a hybrid molecule. Velocity centrifugation studies in alkaline sucrose gradients eliminated the possibility that supercoiled circular SV40 DNA is present in the adenovirus capsids. The DNA obtained from the adenovirus-encapsidated particles of the Ad2++ HEY population appears to consist of nonhybrid Ad2 DNA and Ad2-SV40 hybrid DNA molecules. PMID:4322081

  13. Acid tolerance in amphibians

    SciTech Connect

    Pierce, B.A.

    1985-04-01

    Studies of amphibian acid tolerance provide information about the potential effects of acid deposition on amphibian communities. Amphibians as a group appear to be relatively acid tolerant, with many species suffering increased mortality only below pH 4. However, amphibians exhibit much intraspecific variation in acid tolerance, and some species are sensitive to even low levels of acidity. Furthermore, nonlethal effects, including depression of growth rates and increases in developmental abnormalities, can occur at higher pH.

  14. Toxicity of adipic acid.

    PubMed

    Kennedy, Gerald L

    2002-05-01

    Adipic acid has very low acute toxicity in rats with an LD50 > 5000 mg/kg. Adipic acid produced mild to no skin irritation on intact guinea pig skin as a 50% concentration in propylene glycol; it was not a skin sensitizer. Adipic acid caused mild conjunctival irritation in washed rabbit eyes; in unwashed rabbit eyes, there was mild conjunctival irritation, minimal iritis, but no corneal effects. Adipic acid dust may irritate the mucous membranes of the lungs and nose. In a 2-year feeding study, rats fed adipic acid at concentrations up to 5% in the diet exhibited only weight loss. Adipic acid is not genetically active in a wide variety of assay systems. Adipic acid caused no developmental toxicity in mice, rats, rabbits, or hamsters when administered orally. Adipic acid is partially metabolized in humans; the balance is eliminated unchanged in the urine. Adipic acid is slightly to moderately toxic to fish, daphnia, and algae in acute tests. PMID:12024802

  15. Acid Thunder: Acid Rain and Ancient Mesoamerica

    ERIC Educational Resources Information Center

    Kahl, Jonathan D. W.; Berg, Craig A.

    2006-01-01

    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  16. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    This communication notes the actual magnitude of the acidity in acidic fog particles and suggests a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air.

  17. [Amino acids in saliva].

    PubMed

    Klinger, G; Gruhn, K

    1984-01-01

    Total amino acids in saliva and free and peptide-bound amino acids from 21 saliva samples were determined. The contents of amino acids was 25 mmol/1; total nitrogen content was 78-80 mmol/1. Amino acids consist of Prolin in 25%. Some patients were examined before and after application of the depot estrogen ethinyl estradiosulfonat, which stimulates the assimilation of protein. After application, amino acids increased and the authors found a shift between the single amino acids. Estrogen medication induced an increase in proteins with the character of collagens. Clinical effects are discussed. (author's modified) PMID:6240853

  18. Therapeutic nucleic acids: current clinical status.

    PubMed

    Sridharan, Kannan; Gogtay, Nithya Jaideep

    2016-09-01

    Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are simple linear polymers that have been the subject of considerable research in the last two decades and have now moved into the realm of being stand-alone therapeutic agents. Much of this has stemmed from the appreciation that they carry out myriad functions that go beyond mere storage of genetic information and protein synthesis. Therapy with nucleic acids either uses unmodified DNA or RNA or closely related compounds. From both a development and regulatory perspective, they fall somewhere between small molecules and biologics. Several of these compounds are in clinical development and many have received regulatory approval for human use. This review addresses therapeutic uses of DNA based on antisense oligonucleotides, DNA aptamers and gene therapy; and therapeutic uses of RNA including micro RNAs, short interfering RNAs, ribozymes, RNA decoys and circular RNAs. With their specificity, functional diversity and limited toxicity, therapeutic nucleic acids hold enormous promise. However, challenges that need to be addressed include targeted delivery, mass production at low cost, sustaining efficacy and minimizing off-target toxicity. Technological developments will hold the key to this and help accelerate drug approvals in the years to come. PMID:27111518

  19. Effect of growth hormone on ribonucleic acid metabolism. The template activity of the chromatin and molecular species of ribonucleic acid synthesized after treatment with the hormone

    PubMed Central

    Gupta, S. L.; Talwar, G. P.

    1968-01-01

    Growth hormone stimulates the synthesis of RNA in hypophysectomized rat liver. The question whether the hormonal stimulation of RNA synthesis is due to the activation of repressed cistrons or to other factors was studied. Nuclear RNA from the livers of adult female hypophysectomized and growth-hormone-treated rats was examined for molecular homology by hybridization techniques: no new species of RNA were detected after hormone treatment. The template activity of the chromatin for RNA synthesis is also not increased by the action of growth hormone. Short- and long-pulse-labelling experiments demonstrate that the hormonal stimulation of RNA synthesis is most marked in experiments where the period of incorporation of radioactive precursors is limited to 1–2hr. It is concluded that the hormone influences essentially the rate of RNA synthesis in these tissues. PMID:5701666

  20. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, ... discusses poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  1. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount ... the blood in people with very high triglycerides. Omega-3 fatty acids are in a class of medications ...

  2. Omega-6 Fatty Acids

    MedlinePlus

    Omega-6 fatty acids are types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean oils. Other types of omega-6 fatty acids are found in black currant seed, borage seed, ...

  3. Zoledronic Acid Injection

    MedlinePlus

    Zoledronic acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and weak ... of life,' end of regular menstrual periods). Zoledronic acid (Reclast) is also used to treat osteoporosis in ...

  4. Aminolevulinic Acid Topical

    MedlinePlus

    Aminolevulinic acid is used in combination with photodynamic therapy (PDT; special blue light) to treat actinic keratoses (small crusty ... skin cancer) of the face or scalp. Aminolevulinic acid is in a class of medications called photosensitizing ...

  5. Acid-fast stain

    MedlinePlus

    The acid-fast stain is a laboratory test that determines if a sample of tissue, blood, or other body ... dye. The slide is then washed with an acid solution and a different stain is applied. Bacteria ...

  6. Uric acid - blood

    MedlinePlus

    Uric acid is a chemical created when the body breaks down substances called purines. Purines are found in some ... dried beans and peas, and beer. Most uric acid dissolves in blood and travels to the kidneys. ...

  7. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  8. Omega-6 Fatty Acids

    MedlinePlus

    ... types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean ... from studying specific omega-6 fatty acids or plant oils containing omega-6 fatty acids. See the separate ...

  9. Uric Acid Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Uric Acid Share this page: Was this page helpful? Also known as: Serum Urate; UA Formal name: Uric Acid Related tests: Synovial Fluid Analysis , Kidney Stone Analysis , ...

  10. Acid-fast stain

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003766.htm Acid-fast stain To use the sharing features on this page, please enable JavaScript. The acid-fast stain is a laboratory test that determines ...

  11. Aminocaproic Acid Injection

    MedlinePlus

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  12. Deoxycholic Acid Injection

    MedlinePlus

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  13. Methylmalonic Acid Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Methylmalonic Acid Share this page: Was this page helpful? Also known as: MMA Formal name: Methylmalonic Acid Related tests: Vitamin B12 and Folate , Homocysteine , Intrinsic ...

  14. Fatty acid analogs

    DOEpatents

    Elmaleh, David R.; Livni, Eli

    1985-01-01

    In one aspect, a radioactively labeled analog of a fatty acid which is capable of being taken up by mammalian tissue and which exhibits an in vivo beta-oxidation rate below that with a corresponding radioactively labeled fatty acid.

  15. Boric acid poisoning

    MedlinePlus

    ... boric acid poisoning usually occurs when someone swallows powdered roach-killing products that contain the chemical. Chronic ... vein (IV) Medicines to treat symptoms Note: Activated charcoal does not effectively treat (absorb) boric acid. For ...

  16. Lactic acid test

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003507.htm Lactic acid test To use the sharing features on this page, please enable JavaScript. Lactic acid is mainly produced in muscle cells and red ...

  17. PRODUCTION OF TRIFLUOROACETIC ACID

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-07-19

    A method is given for the production of improved yields of trifluoroacetic acid. The compound is prepared by oxidizing m-aminobenzotrifluoride with an alkali metal or alkaline earth metal permanganate at a temperature in the range of 80 deg C to 100 deg C while dissolved ln a mixture of water with glacial acetic acid and/or trifluoroacetic acid. Preferably a mixture of water and trifluoroacetic acid ls used as the solvent.

  18. Plant fatty acid hydroxylases

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank

    2001-01-01

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  19. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    The chemical composition of fog particles has become of considerable interest, because of both the possibility of interpreting atmospheric- chemistry processes in fog particles in terms of the principles of aqueous chemistry and the potential health effects of species present in fog particles. The acidity of fog particles has received wide attention. This communication noted the actual magnitude of the excess acidity in acidic fog particles and suggested a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air. (DP)

  20. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  1. What Is Acid Rain?

    ERIC Educational Resources Information Center

    Likens, Gene E.

    2004-01-01

    Acid rain is the collective term for any type of acidified precipitation: rain, snow, sleet, and hail, as well as the presence of acidifying gases, particles, cloud water, and fog in the atmosphere. The increased acidity, primarily from sulfuric and nitric acids, is generated as a by-product of the combustion of fossil fuels such as coal and oil.…

  2. Acid Rain Study Guide.

    ERIC Educational Resources Information Center

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  3. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  4. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor L.; Brow, Mary Ann D.; Dahlberg, James E.

    2007-12-11

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  5. Amino acid analysis

    NASA Technical Reports Server (NTRS)

    Winitz, M.; Graff, J. (Inventor)

    1974-01-01

    The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

  6. Editorial: Acid precipitation

    SciTech Connect

    1995-09-01

    This editorial focuses on acid rain and the history of public and governmental response to acid rain. Comments on a book by Gwineth Howell `Acid Rain and Acid Waters` are included. The editor feels that Howells has provide a service to the environmental scientific community, with a textbook useful to a range of people, as well as a call for decision makers to learn from the acid rain issue and use it as a model for more sweeping global environmental issues. A balance is needed among several parameters such as level of evidence, probability that the evidence will lead to a specific direction and the cost to the global community. 1 tab.

  7. Cleavage of nucleic acids

    SciTech Connect

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow; Mary Ann D.; Dahlberg, James E.

    2010-11-09

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  8. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann D.; Dahlberg, James E.

    2000-01-01

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  9. Nucleic acid detection assays

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James E.

    2005-04-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  10. Nucleic acid detection compositions

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James L.

    2008-08-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  11. Acidic Ionic Liquids.

    PubMed

    Amarasekara, Ananda S

    2016-05-25

    Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition. PMID:27175515

  12. Nucleic acid detection kits

    DOEpatents

    Hall, Jeff G.; Lyamichev, Victor I.; Mast, Andrea L.; Brow, Mary Ann; Kwiatkowski, Robert W.; Vavra, Stephanie H.

    2005-03-29

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof. The present invention further relates to methods and devices for the separation of nucleic acid molecules based on charge. The present invention also provides methods for the detection of non-target cleavage products via the formation of a complete and activated protein binding region. The invention further provides sensitive and specific methods for the detection of nucleic acid from various viruses in a sample.

  13. Demospongic Acids Revisited

    PubMed Central

    Kornprobst, Jean-Michel; Barnathan, Gilles

    2010-01-01

    The well-known fatty acids with a Δ5,9 unsaturation system were designated for a long period as demospongic acids, taking into account that they originally occurred in marine Demospongia sponges. However, such acids have also been observed in various marine sources with a large range of chain-lengths (C16–C32) and from some terrestrial plants with short acyl chains (C18–C19). Finally, the Δ5,9 fatty acids appear to be a particular type of non-methylene-interrupted fatty acids (NMA FAs). This article reviews the occurrence of these particular fatty acids in marine and terrestrial organisms and shows the biosynthetic connections between Δ5,9 fatty acids and other NMI FAs. PMID:21116406

  14. Process for the preparation of lactic acid and glyceric acid

    DOEpatents

    Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

    2008-12-02

    Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

  15. Microorganisms for producing organic acids

    SciTech Connect

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  16. Acid-Base Homeostasis

    PubMed Central

    Nakhoul, Nazih; Hering-Smith, Kathleen S.

    2015-01-01

    Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. The importance of this regulation is evidenced by a variety of physiologic derangements that occur when plasma pH is either high or low. The kidneys have the predominant role in regulating the systemic bicarbonate concentration and hence, the metabolic component of acid-base balance. This function of the kidneys has two components: reabsorption of virtually all of the filtered HCO3− and production of new bicarbonate to replace that consumed by normal or pathologic acids. This production or generation of new HCO3− is done by net acid excretion. Under normal conditions, approximately one-third to one-half of net acid excretion by the kidneys is in the form of titratable acid. The other one-half to two-thirds is the excretion of ammonium. The capacity to excrete ammonium under conditions of acid loads is quantitatively much greater than the capacity to increase titratable acid. Multiple, often redundant pathways and processes exist to regulate these renal functions. Derangements in acid-base homeostasis, however, are common in clinical medicine and can often be related to the systems involved in acid-base transport in the kidneys. PMID:26597304

  17. Citric Acid Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie L. (Compiler)

    2013-01-01

    The Ground Systems Development and Operations GSDO) Program at NASA John F. Kennedy Space Center (KSC) has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of the GSDO Program, the purpose of this project is to demonstratevalidate citric acid as a passivation agent for stainless steel. Successful completion of this project will result in citric acid being qualified for use as an environmentally preferable alternative to nitric acid for passivation of stainless steel alloys in NASA and DoD applications.

  18. USGS Tracks Acid Rain

    USGS Publications Warehouse

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  19. Recovery of organic acids

    DOEpatents

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  20. Recovery of organic acids

    SciTech Connect

    Verser, Dan W.; Eggeman, Timothy J.

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  1. THIN-LAYER SEPARATION OF CITRIC ACID CYCLE INTERMEDIATES, LACTIC ACID, AND THE AMINO ACID TAURINE

    EPA Science Inventory

    This paper describes a two-dimensional mixed-layer method for separating citric acid cycle intermediates, lactic acid and the amino acid taurine. The method cleanly separates all citric acid cycle intermediates tested, excepting citric acid and isocitric acid. The solvents are in...

  2. Toxicology of Perfluoroalkyl acids

    EPA Science Inventory

    The Perfluoroalkyl acids(PFAAs) area a family of organic chemicals consisting of a perflurinated carbon backbone (4-12in length) and a acidic functional moiety (Carboxylate or sulfonate). These compounds have excellent surface-tension reducing properties and have numerous industr...

  3. Toxicology of Perfluoroalkyl Acids*

    EPA Science Inventory

    The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

  4. Lead-acid cell

    SciTech Connect

    Hradcovsky, R.J.; Kozak, O.R.

    1980-12-09

    A lead-acid storage battery is described that has a lead negative electrode, a lead dioxide positive electrode and a sulfuric acid electrolyte having an organic catalyst dissolved therein which prevents dissolution of the electrodes into lead sulfate whereby in the course of discharge, the lead dioxide is reduced to lead oxide and the lead is oxidized.

  5. Proteins and Amino Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteins are the most abundant substances in living organisms and cells. All proteins are constructed from the same twenty amino acids that are linked together by covalent bonds. Shorter chains of two or more amino acids can be linked by covalent bonds to form polypeptides. There are twenty amino...

  6. EFFECTS OF ACID PRECIPITATION

    EPA Science Inventory

    Recent reviews of available data indicate that precipitation in a large region of North America is highly acidic when its pH is compared with the expected pH value of 5.65 for pure rain water in equilibrium with CO2. A growing body of evidence suggests that acid rain is responsib...

  7. Bile acid transporters

    PubMed Central

    Dawson, Paul A.; Lan, Tian; Rao, Anuradha

    2009-01-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na+ taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTα-OSTβ. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers. PMID:19498215

  8. Fats and fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The absolute fat requirement of the human species is the amount of essential fatty acids needed to maintain optimal fatty acid composition of all tissues and normal eicosanoid synthesis. At most, this requirement is no more than about 5% of an adequate energy intake. However, fat accounts for appro...

  9. Analysis of Organic Acids.

    ERIC Educational Resources Information Center

    Griswold, John R.; Rauner, Richard A.

    1990-01-01

    Presented are the procedures and a discussion of the results for an experiment in which students select unknown carboxylic acids, determine their melting points, and investigate their solubility behavior in water and ethanol. A table of selected carboxylic acids is included. (CW)

  10. EXPOSURES TO ACIDIC AEROSOLS

    EPA Science Inventory

    Ambient monitoring of acid aerosol in four U.S. cities and in a rural region of southern Ontario clearly show distinct periods of strong acidity. easurements made in Kingston, TN, and Stuebenville, OH, resulted in 24-hr H+ ion concentrations exceeding 100 nmole/m3 more than 10 ti...

  11. Mutant fatty acid desaturase

    DOEpatents

    Shanklin, John; Cahoon, Edgar B.

    2004-02-03

    The present invention relates to a method for producing mutants of a fatty acid desaturase having a substantially increased activity towards fatty acid substrates with chains containing fewer than 18 carbons relative to an unmutagenized precursor desaturase having an 18 carbon atom chain length substrate specificity. The method involves inducing one or more mutations in the nucleic acid sequence encoding the precursor desaturase, transforming the mutated sequence into an unsaturated fatty acid auxotroph cell such as MH13 E. coli, culturing the cells in the absence of supplemental unsaturated fatty acids, thereby selecting for recipient cells which have received and which express a mutant fatty acid desaturase with an elevated specificity for fatty acid substrates having chain lengths of less than 18 carbon atoms. A variety of mutants having 16 or fewer carbon atom chain length substrate specificities are produced by this method. Mutant desaturases produced by this method can be introduced via expression vectors into prokaryotic and eukaryotic cells and can also be used in the production of transgenic plants which may be used to produce specific fatty acid products.

  12. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount of triglycerides (a fat-like ... people with very high triglycerides. Omega-3 fatty acids are in a class of medications called antilipemic ...

  13. Salicylic Acid Topical

    MedlinePlus

    Propa pH® Peel-Off Acne Mask ... pimples and skin blemishes in people who have acne. Topical salicylic acid is also used to treat ... medications called keratolytic agents. Topical salicylic acid treats acne by reducing swelling and redness and unplugging blocked ...

  14. Amino Acid Crossword Puzzle

    ERIC Educational Resources Information Center

    Sims, Paul A.

    2011-01-01

    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  15. Computational Approaches to Nucleic Acid Origami.

    PubMed

    Jabbari, Hosna; Aminpour, Maral; Montemagno, Carlo

    2015-10-12

    Recent advances in experimental DNA origami have dramatically expanded the horizon of DNA nanotechnology. Complex 3D suprastructures have been designed and developed using DNA origami with applications in biomaterial science, nanomedicine, nanorobotics, and molecular computation. Ribonucleic acid (RNA) origami has recently been realized as a new approach. Similar to DNA, RNA molecules can be designed to form complex 3D structures through complementary base pairings. RNA origami structures are, however, more compact and more thermodynamically stable due to RNA's non-canonical base pairing and tertiary interactions. With all these advantages, the development of RNA origami lags behind DNA origami by a large gap. Furthermore, although computational methods have proven to be effective in designing DNA and RNA origami structures and in their evaluation, advances in computational nucleic acid origami is even more limited. In this paper, we review major milestones in experimental and computational DNA and RNA origami and present current challenges in these fields. We believe collaboration between experimental nanotechnologists and computer scientists are critical for advancing these new research paradigms. PMID:26348196

  16. Induction of cellular deoxyribonucleic acid synthesis in butyrate-treated cells by simian virus 40 deoxyribonucleic acid

    SciTech Connect

    Kawasaki, S.; Diamond, L.; Baserga, R.

    1981-11-01

    Sodium butyrate (3mM) inhibited the entry into the S phase of quiescent 3T3 cells stimulated by serum, but had no effect on the accumulation of cellular ribonucleic acid. Simian virus 40 infection or manual microinjection of cloned fragments from the simian virus 40 A gene caused quiescent 3T3 cells to enter the S phase even in the presence of butyrate. NGI cells, a line of 3T3 cells transformed by simian virus 40, grew vigorously in 3 mM butyrate. Homokaryons were formed between G/sub 1/ and S-phase 3T3 cells. Butyrate inhibited the induction of deoxyribonucleic acid synthesis that usually occurs in G/sub 1/ nuclei when G/sub 1/ cells are fused with S-phase cells. However, when G/sub 1/ 3T3 cells were fused with exponentially growing NGI cells, the 3T3 nuclei were induced to enter deoxyribonucleic acid synthesis. In tsAF8 cells, a ribonucleic acid polymerase II mutant that stops in the G/sub 1/ phase of the cell cycle, no temporal sequence was demonstrated between the butyrate block and the temperature-sensitive block. These results confirm previous reports that certain virally coded proteins can induce cell deoxyribonucleic acid synthesis in the absence of cellular functions that are required by serum-stimulated cells. The author's interpretation of these data is that butyrate inhibited cell growth by inhibiting the expression of genes required for the G/sub o/ ..-->.. G/sub 1/ ..-->.. S transition and that the product of the simian virus 40 A gene overrode this inhibition by providing all of the necessary functions for the entry into the S phase.

  17. Trans Fatty Acids

    NASA Astrophysics Data System (ADS)

    Doyle, Ellin

    1997-09-01

    Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.

  18. Sulfuric Acid on Europa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain.

    This image is based on data gathered by Galileo's near infrared mapping spectrometer.

    Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks.

    Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  19. Strongly Acidic Auxin Indole-3-Methanesulfonic Acid

    PubMed Central

    Cohen, Jerry D.; Baldi, Bruce G.; Bialek, Krystyna

    1985-01-01

    A radiochemical synthesis is described for [14C]indole-3-methanesulfonic acid (IMS), a strongly acidic auxin analog. Techniques were developed for fractionation and purification of IMS using normal and reverse phase chromatography. In addition, the utility of both Fourier transform infrared spectrometry and fast atom bombardment mass spectrometry for analysis of IMS has been demonstrated. IMS was shown to be an active auxin, stimulating soybean hypocotyl elongation, bean first internode curvature, and ethylene production. IMS uptake by thin sections of soybean hypocotyl was essentially independent of solution pH and, when applied at a 100 micromolar concentration, IMS exhibited a basipetal polarity in its transport in both corn coleoptile and soybean hypocotyl sections. [14C]IMS should, therefore, be a useful compound to study fundamental processes related to the movement of auxins in plant tissues and organelles. PMID:16664007

  20. Ribonucleic acid synthesis in the renal cortex at the initiation of compensatory growth.

    PubMed Central

    Cortes, P; Levin, N W; Martin, P R

    1976-01-01

    The mechanisms responsible for the increase in RNA per cell during the first 48h of renal compensatory growth were studied in the renal cortex. Unilaterally nephrectomized, sham-operated or non-operated rats were used. Incorporation into RNA of labelled precursors was studied in vivo and in vitro. Sham-operation produced significant changes in precursor incorporation, absolute amounts of UTP and RNA, and the rate of RNA synthesis. At 6h after surgery, the amount of RNA decreased in sham-operated controls, whereas that in growing cortex remained unchanged. Incorporation into RNA in vivo was greater in the growing cortex, although the rate of RNA synthesis was not increased. At 24h, precursor incorporation into RNA and UTP and RNA synthesis were all increased in the growing cortex. In contrast with results obtained in vivo, slices of growing cortex incorporated less labelled precursor into RNA than did cortex slices from sham-operated controls, from 3 to 48h. Maximal differences were found from 6 to 24h. An attempt was made to equalize endogenous precursor pool sizes by increasing the concentration of unlabelled uridine in the media; incorporation differences were narrowed significantly. Serum from nephrectomized animals did not increase precursor incorporation into RNA in vitro. An increase in RNA synthesis is an important factor in RNA accretion in the renal cortex beyond 12h of compensatory growth. This is accompanied by increased UTP content and preceded by expansion of other pools. The amount of labelled precursor incorporated into RNA is greatly influenced by its delivery rate to the growing kidney in vivo and by intracellular dilution of expanded precursor pools in vitro. PMID:985437

  1. Nucleolar 4s ribonucleic acid in dipteran salivary glands in the presence of inhibitor

    PubMed Central

    Sirlin, J. L.; Loening, U. E.

    1968-01-01

    1. Salivary glands of insect larvae accumulate newly made transfer RNA in the nucleolus when maintained in the presence of nucleoside antagonists that inhibit RNA synthesis preferentially at the chromosome. 2. The nucleus contains precursor transfer RNA, which, on the basis of the general evidence, may originate in the chromosome and then be methylated in the nucleolus. 3. The maturation of precursor ribosomal RNA is blocked in the nucleolus during inhibition. 4. The transport of nuclear RNA to cytoplasm is also blocked. 5. It is suggested that, if the transfer RNA accumulated in the nucleolus does indeed originate in the chromosome, the accumulation may result from the blockage of an obligatory transient association of the RNA with the nucleolus. PMID:4176517

  2. Low-molecular-weight (4.5S) ribonucleic acid in higher-plant chloroplast ribosomes.

    PubMed Central

    Whitfeld, P R; Leaver, C J; Bottomley, W; Atchison, B

    1978-01-01

    A species of RNA that migrates on 10% (w/v) polyacrylamide gels between 5S and 4S RNA was detected in spinach chloroplasts. This RNA (referred to as 4.5 S RNA) was present in amounts equimolar to the 5S RNA and its molecular weight was estimated to be approx. 33 000. Fractionation of the chloroplast components showed that the 4.5S RNA was associated with the 50 S ribosomal subunit and that it could be removed by washing the ribosomes with a buffer containing 0.01 M-EDTA and 0.5 M-KCl. It did not appear to be a cleavage product of the labile 23 S RNA of spinach chloroplast ribosomes. When 125I-labelled 4.5 S RNA was hybridized to fragments of spinach chloroplast DNA produced by SmaI restriction endonuclease, a single fragment (mol.wt. 1.15 times 10(6)) became labelled. The same DNA fragment also hybridized to chloroplast 5 S RNA and part of the 23 S RNA. It was concluded that the coding sequence for 4.5 S RNA was part of, or immediately adjacent to, the rRNA-gene region in chloroplast DNA . A comparable RNA species was observed in chloroplasts of tobacco and pea leaves. Images Fig. 8. PMID:743229

  3. Chain extension of ribonucleic acid by enzymes from rat liver cytoplasm

    PubMed Central

    Wilkie, N. M.; Smellie, R. M. S.

    1968-01-01

    1. The 105000g supernatant fraction of rat liver catalyses the incorporation of ribonucleotides from ribonucleoside triphosphates into polyribonucleotide material. The reaction requires Mg2+ ions and is enhanced by the addition of an ATP-generating system and RNA, ATP, UTP and CTP but not GTP are utilized in this reaction. In the case of UTP, the product is predominantly a homopolymer containing 2–3 uridine residues, and there is evidence that these may be added to the 3′-hydroxyl ends of RNA or oligoribonucleotide primers. 2. The microsome fraction of rat liver incorporates ribonucleotides from ATP, GTP, CTP and UTP into polyribonucleotide material. This reaction requires Mg2+ ions and is enhanced slightly by the addition of an ATP-generating system, and by RNA but not DNA. Supplementation of the reaction mixture with the three complementary ribonucleoside 5′-triphosphates greatly increases the utilization of a single labelled ribonucleoside 5′-triphosphate. The optimum pH is in the range 7·0–8·5, and the reaction is strongly inhibited by inorganic pyrophosphate and to a much smaller degree by inorganic orthophosphate. It is not inhibited by actinomycin D or by deoxyribonuclease. In experiments with [32P]UTP in the absence of ATP, GTP and CTP, 80–90% of 32P was recovered in UMP-2′ or -3′ after alkaline hydrolysis of the reaction product. When the reaction mixture was supplemented with ATP, GTP and CTP, however, about 40% of the 32P was recovered in nucleotides other than UMP-2′ or -3′. Although the reactions seem to lead predominantly to the synthesis of homopolymers, the possibility of some formation of some heteropolymer is not completely excluded. PMID:5683501

  4. Localization of glucocorticoid receptor messenger ribonucleic acid in hippocampus of rat brain using in situ hybridization.

    PubMed

    Yang, G; Matocha, M F; Rapoport, S I

    1988-08-01

    An in situ hybridization procedure was applied to quantify glucocorticoid receptor (GR) mRNAs in the hippocampus of rat brain. Hybridization was carried out using a radiolabeled antisense probe complementary to the rat liver GR gene. The specificity of the method was validated by showing: 1) a high cellular grain density in sections hybridized with an antisense but not a sense probe; 2) agreement between the experimental and theoretical temperature at which 50% of the hybrids melted, and 3) a high signal distribution of GR mRNA in the hippocampus, a region of brain known to preferentially concentrate steroid hormones. Within the hippocampus, however, subregional differences in hybridization densities were observed. Quantitative autoradiography indicated that the average neuronal silver grain number was highest in the pyramidal cell layers of CA2 and CA4 and lowest in those of CA1 and CA3. Also, there was a significant difference in the average grain number between all of the cell fields except for that between CA2 and CA4. These results show that contiguous but neuroanatomically distinct cell fields of the hippocampus express different levels of GR transcripts, and indicate that differential regulation of GR expression occurs in subpopulations of hippocampal neurons. PMID:3211154

  5. Induction of avidin messenger ribonucleic acid in the chick oviduct by progesterone and other steroids.

    PubMed

    Kunnas, T A; Joensuu, T K; Viitala, K K; Sopanen, P; Tuohimaa, P; Kulomaa, M S

    1992-06-01

    Avidin gene expression was analyzed using an avidin immunoassay and RNA hybridization analysis. To ascertain whether the induction of the avidin gene by progesterone remains specific also during secondary restimulation with diethylstilbestrol, chicks were given different steroid hormones or hormone combinations. Progesterone-specific induction of avidin protein and messenger RNA (mRNA) was 15- to 30-fold over the control even after secondary restimulation with diethylstilbestrol. A functional difference between the progesterone response element and glucocorticoid response element was suggested, since dexamethasone alone did not induce avidin in vivo. In spite of progesterone specificity, a combination of progesterone with other steroids nevertheless generated a synergistic increase in the amount of avidin mRNA. This may indicate that binding of progesterone receptor to the progesterone response element may be important to alter the functional activity of other hormone response elements present on the avidin gene. The time response curve of the avidin mRNA induction by progesterone was also determined. Avidin mRNA was detectable 8 h after progesterone induction, and its amount was maximal after 16-24 h. This would indicate that the avidin gene belongs in the so-called late responder genes, which also include chicken ovalbumin, ovomucoid, and lysozyme genes. PMID:1375902

  6. Effects of daidzein on messenger ribonucleic Acid expression of gonadotropin receptors in chicken ovarian follicles.

    PubMed

    Liu, H Y; Zhang, C Q

    2008-03-01

    Effects of daidzein on expression of mRNA of gonadotropin receptors [follicle-stimulating hormone receptor (FSHR), luteinizing hormone receptor (LHR)] were evaluated in ovarian follicles of ISA laying hens that were 13 mo old in the postpeak period of egg laying. The hens were randomly allocated as control and daidzein-treated groups, with daidzein supplemented to the basal diet at the level of 10 mg/kg for 7 wk. The granulosa layers of preovulatory follicles (F1, F2, F3, F4, F5) and follicular layers of the small yellow follicle (SYF), large white follicle (LWF), and atretic follicle were collected. The mRNA expression of related genes was measured by semiquantitative reverse transcription PCR. Results showed that daidzein significantly increased the egg-laying rate (P < 0.05) and the number of SYF and LWF (P < 0.05). The relative abundance of the FSHR mRNA decreased in the granulosa layers from F5 to F1, but LHR mRNA displayed the opposite trend in developmental changes. Treatment with daidzein resulted in increased expression of FSHR mRNA in LWF, SYF, and granulosa layers of F4 to F2 and LHR mRNA in granulosa layers of F4 and F1 (P < 0.05). These results indicated that dietary supplementation of daidzein upregulated mRNA expression of gonadotropin receptors to improve follicle development in chicken developing follicles and laying performance after the peak laying period. PMID:18281582

  7. AR3 messenger ribonucleic acid expression and its functional implication in human primary testicular failure.

    PubMed

    Tian, F; Wu, Y-S; Zhao, J; Li, W

    2014-10-01

    AR3, a major one of androgen receptor (AR) splice variants, has been shown to play a pivotal role in concert with AR signalling in prostate cancer. The present study was undertaken to characterise the expression pattern of AR3 in normal and impaired spermatogenesis. Expression of AR3 mRNA showed significantly lower level in testicular tissues with impaired spermatogenesis when compared to normal tissues. This aberrant expression profile of AR3 in human pathological testes was further confirmed by immunoblotting analysis. Moreover, in situ hybridisation studies revealed that the transcripts of the gene were dominantly localised in the pachytene spermatocytes and round spermatids, suggesting a potential involvement of this transcriptional regulator in the auto-/paracrine regulation of meiotic and post-meiotic differentiation. This hypothesis was strengthened by the observation that AR3 mRNA expression was positively correlated to average seminiferous tubule score and was negatively correlated to serum FSH level. To the best of our knowledge, such a distinct expression profile of AR3 has not been reported previously in human testis. Overall, our data are suggestive of a novel site of action of AR3 during human spermatogenesis and should shed light on the complicated circuit composed of AR and its splice variants. PMID:24124902

  8. The synthesis of ribonucleic acid during inhibition of Escherichia coli by chlortetracycline

    PubMed Central

    Holmes, Isobel A.; Wild, D. G.

    1965-01-01

    1. During inhibition of Escherichia coli by chlortetracycline, protein synthesis was sharply reduced whereas synthesis of RNA was much less affected. 2. Most of the RNA made during inhibition was contained in particles that sedimented more slowly than ribosomes. 3. The particles were more sensitive than ribosomes to degradation by ultrasonic vibrations and ribonuclease and differed from ribosomes in their behaviour during chromatography on DEAE-cellulose. 4. The particles contained two species of RNA that differed slightly in their sedimentation properties from the two RNA components found in ribosomes. 5. The nature of the events taking place during inhibition by chlortetracycline is discussed with particular reference to the status of the particles that accumulate and to the mode of action of this and other antibiotics. ImagesFig. 2. PMID:16749115

  9. 4.5S ribonucleic acid, a novel ribosome component in the chloroplasts of flowering plants.

    PubMed Central

    Bowman, C M; Dyer, T A

    1979-01-01

    A species of low-molecular-weight ribosomal RNA, referred to as '4.5S rRNA', was found in addition to 5S rRNA in the large subunit of chloroplast ribosomes of a wide range of flowering plants. It was shown by sequence analysis that several variants of this RNA may occur in a plant. Furthermore, although in most flowering plants the predominant variant contains about 100 nucleotides, in the broad bean it has less than 80. It seems, therefore, to be much more diverse in size and sequence than the other ribosomal RNA species. Like 5S rRNA , it does not contain modified nucleotides and it is also unusual in having an unphosphorylated 5'-end. It is apparently neither a homologue of cytosol 5.8S rRNA nor a fragment of 23S rRNA. Images Fig. 1. Fig. 3. Fig. 4. PMID:540035

  10. Magnesium ions and the structure of Escherichia coli ribosomal ribonucleic acid

    PubMed Central

    Rodgers, A.

    1966-01-01

    1. The effect of removing Mg2+ from a purified high-molecular-weight (1·07×106) fraction of Escherichia coli ribosomal RNA was examined by ultracentrifugation, thermal denaturation and optical rotation. 2. At moderate I (0·1m-sodium chloride), EDTA at 2–50mm has little effect on RNA; at low I, 0·01–0·04 (with tris as counter-ion), two boundaries appear. 3. The leading boundary, S20,w about 20s, is identified with the original material with counter-ion Mg2+ (`ionic atmosphere') removed, leading to an expanded form. 4. The slow boundary, 15–16s, is associated with a further loss of Mg2+ and a further expansion, sensitive to EDTA concentration: it is proposed that this Mg2+ is localized on the polynucleotide chain, i.e. `site-bound'. 5. I is important and the EDTA effect at low I is reversible if Na+ is added immediately after the EDTA: this Na+ reversibility is lost on standing at 0°. It is suggested that changes in the tertiary structure may be associated with this loss of reversibility. 6. Thermal-denaturation studies show that there is no loss of secondary structure associated with these changes: change in the optical-rotatory-dispersion spectrum in the region of the Cotton effect may be associated with this change in tertiary structure. PMID:4960869

  11. Prostanoid-induced expression of matrix metalloproteinase-1 messenger ribonucleic acid in rat osteosarcoma cells

    NASA Technical Reports Server (NTRS)

    Clohisy, J. C.; Connolly, T. J.; Bergman, K. D.; Quinn, C. O.; Partridge, N. C.

    1994-01-01

    Individual prostanoids have distinct potencies in activating intracellular signaling pathways and regulating gene expression in osteoblastic cells. The E-series prostaglandins (PGs) are known to stimulate matrix metalloproteinase-1 (MMP-1) synthesis and secretion in certain rodent and human osteoblastic cells, yet the intracellular events involved remain unclear. To further characterize this response and its signal transduction pathway(s), we examined prostanoid-induced expression of the MMP-1 gene in the rat osteoblastic osteosarcoma cell line UMR 106-01. Northern blot analysis demonstrated that prostaglandin E2 (PGE2) and PGE1 were very potent stimulators (40-fold) of MMP-1 transcript abundance, PGF2 alpha and prostacyclin were weak stimulators (4-fold), and thromboxane-B2 had no effect. The marked increase in MMP-1 transcript abundance after PGE2 treatment was first detected at 2 h, became maximal at 4 h, and persisted beyond 24 h. This response was dose dependent and elicited maximal and half-maximal effects with concentrations of 10(-6) and 0.6 x 10(-7) M, respectively. Cycloheximide, a protein synthesis inhibitor, completely blocked this effect of PGE2, suggesting that the expression of other genes is required. Nuclear run-on experiments demonstrated that PGE2 rapidly activates MMP-1 gene transcription, with a maximal increase at 2-4 h. The second messenger analog, 8-bromo-cAMP, mimicked the effects of PGE2 by stimulating a dose-dependent increase in MMP-1 messenger RNA (mRNA) levels, with a maximal effect quantitatively similar to that observed with PGE2. Thus, in UMR 106-01 cells, different prostanoids have distinct potencies in stimulating MMP-1 mRNA abundance. Our data suggest that PGE2 stimulation of MMP-1 synthesis is due to activation of MMP-1 gene transcription and a subsequent marked increase in MMP-1 mRNA abundance. This effect is dependent on de novo protein synthesis and is mimicked by protein kinase-A activation.

  12. Evidence for normal vitamin D receptor messenger ribonucleic acid and genotype in absorptive hypercalciuria.

    PubMed

    Zerwekh, J E; Hughes, M R; Reed, B Y; Breslau, N A; Heller, H J; Lemke, M; Nasonkin, I; Pak, C Y

    1995-10-01

    Absorptive hypercalciuria (a stone-forming condition) is characterized by gut hyperabsorption of calcium, hypercalciuria, and reduced bone density. Inasmuch as these features implicate enhanced calcitriol action in gut and bone, we analyzed the vitamin D receptor (VDR) gene to ascertain whether an abnormality of this gene marks patients with intestinal hyperabsorption of calcium. We have compared the frequency of a restriction fragment length polymorphism (Bsm I) associated with different alleles of the VDR gene in a group of 33 well characterized absorptive hypercalciuric patients and a group of 36 normal race- and age-matched control subjects. There was no difference between the distribution of the VDR alleles in the patient population when compared with the normal population. The coding region of VDR messenger RNA was also normal, as determined by both DNA sequence analysis and chemical mismatch cleavage analysis of copy DNA from 11 index absorptive hypercalciuric patients. On the basis of these results, we propose that the enhanced intestinal calcium absorption invariably seen in absorptive hypercalciuria and attendant symptoms of this disorder are not attributable to mutations of the VDR and are not linked to a common VDR genotype. PMID:7559881

  13. Mesenchymal stem cells as novel micro-ribonucleic acid delivery vehicles in kidney disease.

    PubMed

    Yao, Kevin; Ricardo, Sharon D

    2016-05-01

    MicroRNAs (miRNAs) are short single strands of RNA responsible for post-transcriptional regulation of gene expression and have been implicated in the pathogenesis of chronic kidney disease (CKD). Emerging evidence reports that miRNAs can reduce kidney fibrosis through regulation of targets associated with collagen and extracellular matrix accumulation. However, the development of miRNA therapies has been hampered by the lack of targeted and sustainable methods of systemic miRNA delivery. Mesenchymal stem cells (MSCs) provide a promising miRNA delivery platform to overcome toxicity, the potential for insertional mutations and the low efficiency of previous methods. MSCs are endogenously immunoprivileged and home to sites of inflammation. They also release trophic growth factors to modulate the immune system, alter the polarization of macrophages and provide renal protection and repair. The potential to engineer MSCs to express or overexpress miRNAs, released by exosomes, may enhance their natural functions. Clinical studies are already being conducted individually for the use of miRNAs in cancer and MSCs in diseases associated with CKD. Hence, the combination of miRNAs and MSCs may provide an unparalleled cell-based therapy for treating CKD. PMID:26437381

  14. The Occurrence and Distribution of Poly(A) Ribonucleic Acid in Soybean

    PubMed Central

    Key, Joe L.; Silflow, Carolyn

    1975-01-01

    The occurrence and distribution of poly(A) sequences in the RNA of soybean (Glycine max var. Wayne) have been studied. Only one of the two species of AMP-rich RNA contains poly(A). D-RNA does not contain detectable poly(A) sequences. The TB-RNA is the poly(A) RNA in this system. At least a part (up to 50% or more) of the mRNA in polyribosomes contains a poly(A) sequence. The poly(A) RNA is heterodisperse in size but has a mean size of approximately 18S (2,000 nucleotides) in urea and formamide gels. The poly(A) fragment resulting from ribonuclease A and T1 digestion migrates as a broad band overlapping the 4 to 5.8S regions of the gels with a mean size of somewhat greater than 5S. No evidence was found for the occurrence of a discrete oligo(A) fragment in the poly(A) RNA; however, oligonucleotides which migrate faster than the poly(A) fraction were observed in preparations which were not bound to oligo(dT) cellulose prior to electrophoresis. This oligonucleotide region was enriched in AMP (up to about 65%) as would be expected after ribonuclease A and T1 digestion. PMID:16659304

  15. Evolution of early life inferred from protein and ribonucleic acid sequences

    NASA Technical Reports Server (NTRS)

    Dayhoff, M. O.; Schwartz, R. M.

    1978-01-01

    The chemical structures of ferredoxin, 5S ribosomal RNA, and c-type cytochrome sequences have been employed to construct a phylogenetic tree which connects all major photosynthesizing organisms: the three types of bacteria, blue-green algae, and chloroplasts. Anaerobic and aerobic bacteria, eukaryotic cytoplasmic components and mitochondria are also included in the phylogenetic tree. Anaerobic nonphotosynthesizing bacteria similar to Clostridium were the earliest organisms, arising more than 3.2 billion years ago. Bacterial photosynthesis evolved nearly 3.0 billion years ago, while oxygen-evolving photosynthesis, originating in the blue-green algal line, came into being about 2.0 billion years ago. The phylogenetic tree supports the symbiotic theory of the origin of eukaryotes.

  16. Effect of Light on Ribonucleic Acid Metabolism in Greening Maize Leaves 1

    PubMed Central

    Harel, Eitan; Bogorad, Lawrence

    1973-01-01

    The effect of illumination on the incorporation of labeled precursors into RNA of dark-grown maize (Zea mays) leaves was studied using either 32P-phosphate or double labeling with 14C- and 3H-uridine. In the dark, label was preferentially incorporated into etioplast ribosomal RNAs. Incorporation into this fraction and into lower molecular weight fractions was strongly and preferentially stimulated by light during the first 2 hours of illumination. The effect persisted after illumination was terminated. The possibility that light-induced alterations in plastid ribosomal RNA metabolism may not be required for chlorophyll accumulation in maize is discussed. Sucrose density gradient analyses of ribosomes and of extracted RNA did not reveal light-induced incorporation of label into messenger-like RNA associated with polyribosomes during brief illumination. However, newly produced RNA which seems to be neither ribosomal RNA nor transfer RNA is detectable after illumination for 2.5 hours or longer. PMID:16658268

  17. Factors Affecting the Extraction of Intact Ribonucleic Acid from Plant Tissues Containing Interfering Phenolic Compounds

    PubMed Central

    Newbury, H. John; Possingham, John V.

    1977-01-01

    Using conventional methods it is impossible to extract RNA as uncomplexed intact molecules from the leaves of grapevines (Vitis vinifera L.) and from a number of woody perennial species that contain high levels of reactive phenolic compounds. A procedure involving the use of high concentrations of the chaotropic agent sodium perchlorate prevents the binding of phenolic compounds to RNA during extraction. Analyses of the phenolics present in plant tissues used in these experiments indicate that there is a poor correlation between the total phenolic content and the complexing of RNA. However, qualitative analyses suggest that proanthocyanidins are involved in the tanning of RNA during conventional extractions. PMID:16660134

  18. The effect of reaction with formaldehyde on the sedimentation rates of ribonucleic acids

    PubMed Central

    Fenwick, M. L.

    1968-01-01

    It has been reported that the RNA of several bacteriophages and that of the larger ribosomal sub-units of mammalian cells sediment faster in the presence of 0·1m-sodium chloride than is expected from their estimated molecular weights. The effect of blocking the hydrogen-bonding amino groups of these and other types of RNA was studied. The RNA of phage R17 no longer sedimented anomalously fast after treatment with formaldehyde. In contrast, the larger ribosomal RNA of HeLa cells appeared more aberrant than before, sedimenting faster than tobacco-mosaic-virus RNA (mol.wt. 2×106) in the presence of formaldehyde. The rapidly labelled nuclear 45s RNA of HeLa cells still sedimented faster than the larger ribosomal RNA after reaction with formaldehyde, showing no evidence of disaggregation. It is suggested that both the large ribosomal RNA and the 45s RNA of HeLa cells may have a non-linear structure. PMID:16742611

  19. Localization of glucocorticoid receptor messenger ribonucleic acid in hippocampus of rat brain using in situ hybridization

    SciTech Connect

    Yang, G.; Matocha, M.F.; Rapoport, S.I.

    1988-08-01

    An in situ hybridization procedure was applied to quantify glucocorticoid receptor (GR) mRNAs in the hippocampus of rat brain. Hybridization was carried out using a radiolabeled antisense probe complementary to the rat liver GR gene. The specificity of the method was validated by showing: 1) a high cellular grain density in sections hybridized with an antisense but not a sense probe; 2) agreement between the experimental and theoretical temperature at which 50% of the hybrids melted, and 3) a high signal distribution of GR mRNA in the hippocampus, a region of brain known to preferentially concentrate steroid hormones. Within the hippocampus, however, subregional differences in hybridization densities were observed. Quantitative autoradiography indicated that the average neuronal silver grain number was highest in the pyramidal cell layers of CA2 and CA4 and lowest in those of CA1 and CA3. Also, there was a significant difference in the average grain number between all of the cell fields except for that between CA2 and CA4. These results show that contiguous but neuroanatomically distinct cell fields of the hippocampus express different levels of GR transcripts, and indicate that differential regulation of GR expression occurs in subpopulations of hippocampal neurons.

  20. Discovery of huanglongbing (HLB) pre-symptomatic Ribonucleic acid (RNA) biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing (HLB) is the most devastating citrus disease and is associated with vector-borne Liberibacter. Currently there is no cure for huanglongbing. Visual disease symptoms appear in only a few leaves months after initial Liberibacter exposure compromising disease management by tree removal. S...

  1. The Coding Properties of Lysine-accepting Transfer Ribonucleic Acids from Black-eyed Peas 1

    PubMed Central

    Hague, Donald R.; Kofoid, Eric C.

    1971-01-01

    Lysine-accepting transfer RNA from ungerminated and germinated embryo axes of black-eyed peas (Vigna sinensis L. Savi) was fractionated on benzoylated diethylaminoethyl cellulose and reverse phase Freon columns. Cochromatography indicated the presence of two similar lysyl transfer RNA fractions in each tissue. Ribosome binding studies revealed that the larger of the two fractions in each case is specific for the AAG codon, while the smaller one recognizes AAA and AAG. Possible implications of this difference in quantities of isoacceptors in translation of genetic information are discussed. PMID:16657787

  2. Understanding acid rain

    SciTech Connect

    Budiansky, S.

    1981-06-01

    The complexities of the phenomenon of acid rain are described. Many factors, including meteorology, geology, chemistry, and biology, all play parts. Varying weather, varying soils, the presence of other pollutants and species differences all act to blur the connections between industrial emissions, acid rain, and environmental damage. Some experts believe that the greatest pH shock to lakes occurs during snow melt and runoff in the spring; others believe that much of the plant damage ascribed to acid rain is actually due to the effects of ozone. Much work needs to be done in the area of sampling. Historical data are lacking and sampling methods are not sufficiently accurate. (JMT)

  3. WASTE ACID DETOXIFICATION AND RECLAMATION

    EPA Science Inventory

    This Environmental Security Technology Certification Program (ESTCP) project demonstrated the Waste Acid Detoxification and Reclamation (WADR) systems ability to recover waste electropolish acid solutions generated during the manufacturing of gun-tubes, and reuse the clean acid. ...

  4. Disorders of Amino Acid Metabolism

    MedlinePlus

    ... Aspiration Syndrome Additional Content Medical News Disorders of Amino Acid Metabolism By Lee M. Sanders, MD, MPH NOTE: ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism Amino acids are ...

  5. Acid soldering flux poisoning

    MedlinePlus

    The harmful substances in soldering fluxes are called hydrocarbons. They include: Ammonium chloride Rosin Hydrochloric acid Zinc ... Lee DC. Hydrocarbons. In: Marx JA, Hockberger RS, Walls RM, et ... Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ...

  6. Aminolevulinic Acid Topical

    MedlinePlus

    ... in combination with photodynamic therapy (PDT; special blue light) to treat actinic keratoses (small crusty or scaly ... photosensitizing agents. When aminolevulinic acid is activated by light, it damages the cells of actinic keratosis lesions.

  7. Difficult Decisions: Acid Rain.

    ERIC Educational Resources Information Center

    Miller, John A.; Slesnick, Irwin L.

    1989-01-01

    Discusses some of the contributing factors and chemical reactions involved in the production of acid rain, its effects, and political issues pertaining to who should pay for the clean up. Supplies questions for consideration and discussion. (RT)

  8. Uric acid - urine

    MedlinePlus

    ... to filter fluids and waste normally (chronic glomerulonephritis ) Lead poisoning Long-term (chronic) alcohol use Risks There are ... Elsevier Saunders; 2011:chap 28. Read More Gout Lead poisoning Liver disease Polycythemia vera Uric acid - blood Update ...

  9. Amoxicillin and Clavulanic Acid

    MedlinePlus

    ... is used to treat certain infections caused by bacteria, including infections of the ears, lungs, sinus, skin, ... antibiotics. It works by stopping the growth of bacteria. Clavulanic acid is in a class of medications ...

  10. Hydrofluoric acid poisoning

    MedlinePlus

    Chemical Emergencies: Case Definition: Hydrofluoric Acid . Centers for Disease Control and Prevention, U.S. Dept of Health and Human Services; 2005. Goldfrank LR, ed. Goldfrank's Toxicologic Emergencies . 8th ed. New ...

  11. Lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Bullock, Kathryn R.

    Lead/acid batteries are produced in sizes from less than 1 to 3000 Ah for a wide variety of portable, industrial and automotive applications. Designs include Planté, Fauré or pasted, and tubular electrodes. In addition to the traditional designs which are flooded with sulfuric acid, newer 'valve-regulated" designs have the acid immolibized in a silica gel or absorbed in a porous glass separator. Development is ongoing worldwide to increase the specific power, energy and deep discharge cycle life of this commercially successful system to meet the needs of new applications such as electric vehicles, load leveling, and solar energy storage. The operating principles, current status, technical challenges and commercial impact of the lead/acid battery are reviewed.

  12. Citric acid urine test

    MedlinePlus

    ... used to diagnose renal tubular acidosis and evaluate kidney stone disease. ... tubular acidosis and a tendency to form calcium kidney stones. The following may decrease urine citric acid levels: ...

  13. Pantothenic acid and biotin

    MedlinePlus

    ... JavaScript. Pantothenic acid and biotin are types of B vitamins. They are water-soluble, which means that the ... found in foods that are good sources of B vitamins, including the following: Animal proteins Avocado Broccoli, kale, ...

  14. (Acid rain workshop)

    SciTech Connect

    Turner, R.S.

    1990-12-05

    The traveler presented a paper entitled Susceptibility of Asian Ecosystems to Soil-Mediated Acid Rain Damage'' at the Second Workshop on Acid Rain in Asia. The workshop was organized by the Asian Institute of Technology (Bangkok, Thailand), Argonne National Laboratory (Argonne, Illinois), and Resource Management Associates (Madison, Wisconsin) and was sponsored by the US Department of Energy, the United Nations Environment Program, the United Nations Economic and Social Commission for Asia and the Pacific, and the World Bank. Papers presented on the first day discussed how the experience gained with acid rain in North America and Europe might be applied to the Asian situation. Papers describing energy use projections, sulfur emissions, and effects of acid rain in several Asian countries were presented on the second day. The remaining time was allotted to discussion, planning, and writing plans for a future research program.

  15. Stomach acid test

    MedlinePlus

    Gastric acid secretion test ... The test is done after you have not eaten for a while so fluid is all that remains in ... injected into your body. This is done to test the ability of the cells in the stomach ...

  16. Deoxycholic Acid Injection

    MedlinePlus

    ... severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a ... as a liquid to be injected subcutaneously (just under the skin) by a doctor. Your doctor will ...

  17. Amino Acids and Chirality

    NASA Technical Reports Server (NTRS)

    Cook, Jamie E.

    2012-01-01

    Amino acids are among the most heavily studied organic compound class in carbonaceous chondrites. The abundance, distributions, enantiomeric compositions, and stable isotopic ratios of amino acids have been determined in carbonaceous chondrites fi'om a range of classes and petrographic types, with interesting correlations observed between these properties and the class and typc of the chondritcs. In particular, isomeric distributions appear to correlate with parent bodies (chondrite class). In addition, certain chiral amino acids are found in enantiomeric excess in some chondrites. The delivery of these enantiomeric excesses to the early Earth may have contributed to the origin of the homochirality that is central to life on Earth today. This talk will explore the amino acids in carbonaceous chondritcs and their relevance to the origin of life.

  18. Valproic Acid and Pregnancy

    MedlinePlus

    ... in the treatment of epilepsy, and to treat bipolar disorder and migraines. I have been taking valproic acid ... that women with seizure disorders and women with bipolar disorder might have menstrual problems and difficulty getting pregnant. ...

  19. Amino Acid Metabolism Disorders

    MedlinePlus

    Metabolism is the process your body uses to make energy from the food you eat. Food is ... One group of these disorders is amino acid metabolism disorders. They include phenylketonuria (PKU) and maple syrup ...

  20. Uric acid - blood

    MedlinePlus

    ... High levels of uric acid can sometimes cause gout or kidney disease. You may have this test ... Alcoholism Chemotherapy-related side effects Diabetes Excessive exercise Gout Hypoparathyroidism Lead poisoning Leukemia Medullary cystic kidney disease ...

  1. Citric acid urine test

    MedlinePlus

    ... The test is used to diagnose renal tubular acidosis and evaluate kidney stone disease. Normal Results The ... level of citric acid may mean renal tubular acidosis and a tendency to form calcium kidney stones. ...

  2. Folic Acid Quiz

    MedlinePlus

    ... more easily than natural food folate. Close × Answer: D CORRECT: Folic acid reduces the risk for spina ... g., orange juice and green vegetables). Close × Answer: D CORRECT: Spina bifida and anencephaly are neural tube ...

  3. Folic acid in diet

    MedlinePlus

    ... green leafy vegetables Dried beans and peas (legumes) Citrus fruits and juices Fortified means that vitamins have ... A.D.A.M. Editorial team. Related MedlinePlus Health Topics Folic Acid Browse the Encyclopedia A.D. ...

  4. Amoxicillin and Clavulanic Acid

    MedlinePlus

    ... Amoxicillin is in a class of medications called penicillin-like antibiotics. It works by stopping the growth ... allergic to amoxicillin (Amoxil, Trimox, Wymox), clavulanic acid, penicillin, cephalosporins, or any other medications.tell your doctor ...

  5. Boric Acid Poisoning

    PubMed Central

    Wong, L. C.; Heimbach, M. D.; Truscott, D. R.; Duncan, B. D.

    1964-01-01

    Boric acid poisoning in 11 infants, occurring in the newborn nursery as a result of the accidental and inadvertent use of 2.5% boric acid in the preparation of the formulae, is reported. Five of the infants died. All except two exhibited the classical symptomatology of acute boric acid poisoning, namely, diarrhea, vomiting, erythema, exfoliation, desquamation of the skin, and marked central nervous system irritation. Early manifestations of poisoning were nonspecific, and one patient died before skin manifestations were noted. Peritoneal dialysis, instituted in nine cases, was found to be the most effective method of treatment. It is recommended that boric acid, which is of doubtful therapeutic value, should be completely removed from hospitals, dispensaries and pharmacopoeias. ImagesFig. 1Fig. 2 PMID:14166459

  6. Polymers for acid thickening

    SciTech Connect

    Dixon, K.W.

    1980-09-30

    Acids, thickened with branched emulsion or suspension polymers of diallyldimethylammonium chloride are useful as oil well drilling and fracturing fluids for stimulating well production and in other applications, such as thickeners for cosmetics, paints, adhesives, textiles and printing inks.

  7. Acid-base chemistry

    SciTech Connect

    Hand, C.W.; Blewit, H.L.

    1985-01-01

    The book is not a research compendium and there are no references to the literature. It is a teaching text covering the entire range of undergraduate subject matter dealing with acid-base chemistry (some of it remotely) as taught in inorganic, analytical, and organic chemistry courses. The excellent chapters VII through IX deal in detail with the quantitative aspects of aqueous acid-base equilibria (salt hydrolysis and buffer, titrations, polyprotic and amphoteric substances).

  8. Utilization of acid tars

    SciTech Connect

    Frolov, A.F.; Denisova, T.L.; Aminov, A.N.

    1987-01-01

    Freshly produced acid tar (FPAT), obtained as refinery waste in treating petroleum oils with sulfuric acid and oleum, contains 80% or more sulfuric acid. Of such tars, pond acid tars, which contain up to 80% neutral petroleum products and sulfonated resins, are more stable, and have found applications in the production of binders for paving materials. In this article the authors are presenting results obtained in a study of the composition and reactivity of FPAT and its stability in storage in blends with asphalts obtained in deasphalting operations, and the possibility of using the FPAT in road construction has been examined. In this work, wastes were used which were obtained in treating the oils T-750, KhF-12, I-8A, and MS-14. Data on the change in group chemical composition of FPAT are shown, and the acidity, viscosity, needle penetration, and softening point of acid tars obtained from different grades of oils are plotted as functions of the storage time. It is also shown that the fresh and hardened FPATs differ in their solubilities in various solvents.

  9. Mammalian Fatty Acid Elongases

    PubMed Central

    Jump, Donald B.

    2009-01-01

    Summary Very long chain fatty acids confer functional diversity on cells by variations in their chain length and degree of unsaturation. Microsomal fatty acid elongation represents the major pathway for determining the chain length of saturated, monounsaturated, and polyunsaturated fatty acids in cellular lipids. The overall reaction for fatty acid elongation involves four enzymes and utilizes malonyl CoA, NADPH, and fatty acyl CoA as substrates. While the fundamental pathway and its requirements have been known for many years, recent advances have revealed a family of enzymes involved in the first step of the reaction, i.e., the condensation reaction. Seven fatty acid elongase subtypes (Elovl #1–7) have been identified in the mouse, rat, and human genomes. These enzymes determine the rate of overall fatty acid elongation. Moreover, these enzymes also display differential substrate specificity, tissue distribution, and regulation, making them important regulators of cellular lipid composition as well as specific cellular functions. Herein, methods are described to measure elongase activity, analyze elongation products, and alter cellular elongase expression. PMID:19763486

  10. Neutron Nucleic Acid Crystallography.

    PubMed

    Chatake, Toshiyuki

    2016-01-01

    The hydration shells surrounding nucleic acids and hydrogen-bonding networks involving water molecules and nucleic acids are essential interactions for the structural stability and function of nucleic acids. Water molecules in the hydration shells influence various conformations of DNA and RNA by specific hydrogen-bonding networks, which often contribute to the chemical reactivity and molecular recognition of nucleic acids. However, X-ray crystallography could not provide a complete description of structural information with respect to hydrogen bonds. Indeed, X-ray crystallography is a powerful tool for determining the locations of water molecules, i.e., the location of the oxygen atom of H2O; however, it is very difficult to determine the orientation of the water molecules, i.e., the orientation of the two hydrogen atoms of H2O, because X-ray scattering from the hydrogen atom is very small.Neutron crystallography is a specialized tool for determining the positions of hydrogen atoms. Neutrons are not diffracted by electrons, but are diffracted by atomic nuclei; accordingly, neutron scattering lengths of hydrogen and its isotopes are comparable to those of non-hydrogen atoms. Therefore, neutron crystallography can determine both of the locations and orientations of water molecules. This chapter describes the current status of neutron nucleic acid crystallographic research as well as the basic principles of neutron diffraction experiments performed on nucleic acid crystals: materials, crystallization, diffraction experiments, and structure determination. PMID:26227050

  11. Autophagy on acid.

    PubMed

    Wojtkowiak, Jonathan W; Gillies, Robert J

    2012-11-01

    The microenvironment of solid tumors tends to be more acidic (6.5-7.0) than surrounding normal (7.2-7.4) tissue. Chaotic vasculature, oxygen limitation and major metabolic changes all contribute to the acidic microenvironment. We have previously proposed that low extracellular pH (pHe) plays a critical role in the development and progression of solid tumors. While extracellular acidosis is toxic to most normal cells, cancer cells can adapt and survive under this harsh condition. In this study, we focused on identifying survival strategies employed by cancer cells when challenged with an acidic pHe (6.6-6.7) either acutely or for many generations. While acutely acidic cells did not grow, those acclimated over many generations grew at the same rate as control cells. We observed that these cells induce autophagy in response to acidosis both acutely and chronically, and that this adaptation appears to be necessary for survival. Inhibition of autophagy in low pH cultured cells results in cell death. Histological analysis of tumor xenografts reveals a strong correlation of LC3 protein expression in regions projected to be acidic. Furthermore, in vivo buffering experiments using sodium bicarbonate, previously shown to raise extracellular tumor pH, decreases LC3 protein expression in tumor xenografts. These data imply that autophagy can be induced by extracellular acidosis and appears to be chronically employed as a survival adaptation to acidic microenvironments. PMID:22874557

  12. Method for isolating nucleic acids

    DOEpatents

    Hurt, Jr., Richard Ashley; Elias, Dwayne A.

    2015-09-29

    The current disclosure provides methods and kits for isolating nucleic acid from an environmental sample. The current methods and compositions further provide methods for isolating nucleic acids by reducing adsorption of nucleic acids by charged ions and particles within an environmental sample. The methods of the current disclosure provide methods for isolating nucleic acids by releasing adsorbed nucleic acids from charged particles during the nucleic acid isolation process. The current disclosure facilitates the isolation of nucleic acids of sufficient quality and quantity to enable one of ordinary skill in the art to utilize or analyze the isolated nucleic acids for a wide variety of applications including, sequencing or species population analysis.

  13. Acidification and Acid Rain

    NASA Astrophysics Data System (ADS)

    Norton, S. A.; Veselã½, J.

    2003-12-01

    Air pollution by acids has been known as a problem for centuries (Ducros, 1845; Smith, 1872; Camuffo, 1992; Brimblecombe, 1992). Only in the mid-1900s did it become clear that it was a problem for more than just industrially developed areas, and that precipitation quality can affect aquatic resources ( Gorham, 1955). The last three decades of the twentieth century saw tremendous progress in the documentation of the chemistry of the atmosphere, precipitation, and the systems impacted by acid atmospheric deposition. Chronic acidification of ecosystems results in chemical changes to soil and to surface waters and groundwater as a result of reduction of base cation supply or an increase in acid (H+) supply, or both. The most fundamental changes during chronic acidification are an increase in exchangeable H+ or Al3+ (aluminum) in soils, an increase in H+ activity (˜concentration) in water in contact with soil, and a decrease in alkalinity in waters draining watersheds. Water draining from the soil is acidified and has a lower pH (=-log [H+]). As systems acidify, their biotic community changes.Acidic surface waters occur in many parts of the world as a consequence of natural processes and also due to atmospheric deposition of strong acid (e.g., Canada, Jeffries et al. (1986); the United Kingdom, Evans and Monteith (2001); Sweden, Swedish Environmental Protection Board (1986); Finland, Forsius et al. (1990); Norway, Henriksen et al. (1988a); and the United States (USA), Brakke et al. (1988)). Concern over acidification in the temperate regions of the northern hemisphere has been driven by the potential for accelerating natural acidification by pollution of the atmosphere with acidic or acidifying compounds. Atmospheric pollution ( Figure 1) has resulted in an increased flux of acid to and through ecosystems. Depending on the ability of an ecosystem to neutralize the increased flux of acidity, acidification may increase only imperceptibly or be accelerated at a rate that

  14. Discovery of essential fatty acids

    PubMed Central

    Spector, Arthur A.; Kim, Hee-Yong

    2015-01-01

    Dietary fat was recognized as a good source of energy and fat-soluble vitamins by the first part of the 20th century, but fatty acids were not considered to be essential nutrients because they could be synthesized from dietary carbohydrate. This well-established view was challenged in 1929 by George and Mildred Burr who reported that dietary fatty acid was required to prevent a deficiency disease that occurred in rats fed a fat-free diet. They concluded that fatty acids were essential nutrients and showed that linoleic acid prevented the disease and is an essential fatty acid. The Burrs surmised that other unsaturated fatty acids were essential and subsequently demonstrated that linolenic acid, the omega-3 fatty acid analog of linoleic acid, is also an essential fatty acid. The discovery of essential fatty acids was a paradigm-changing finding, and it is now considered to be one of the landmark discoveries in lipid research. PMID:25339684

  15. Acid Rain, pH & Acidity: A Common Misinterpretation.

    ERIC Educational Resources Information Center

    Clark, David B.; Thompson, Ronald E.

    1989-01-01

    Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

  16. Nitric acid-formic acid compatibility in DWPF

    SciTech Connect

    Eibling, R.E.

    1992-10-20

    The addition of the Nitric Acid Flowsheet to the DWPF feed preparation process introduces nitric acid into a vessel which will subsequently receive a formic acid solution. The combination of these two acids suggests that a denitration reaction might occur. This memorandum reviews the conditions under which a denitration reaction is possible and compares these conditions to DWPF operating conditions.

  17. Amino-acid contamination of aqueous hydrochloric acid.

    NASA Technical Reports Server (NTRS)

    Wolman, Y.; Miller, S. L.

    1971-01-01

    Considerable amino-acid contamination in commercially available analytical grade hydrochloric acid (37% HCl) was found. One bottle contained 8,300 nmol of amino-acids per liter. A bottle from another supplier contained 6,700 nmol per liter. The contaminants were mostly protein amino-acids and several unknowns. Data on the volatility of the amino-acids during HCl distillation were also obtained.

  18. Optical high acidity sensor

    DOEpatents

    Jorgensen, B.S.; Nekimken, H.L.; Carey, W.P.; O`Rourke, P.E.

    1997-07-22

    An apparatus and method for determining acid concentrations in solutions having acid concentrations of from about 0.1 Molar to about 16 Molar is disclosed. The apparatus includes a chamber for interrogation of the sample solution, a fiber optic light source for passing light transversely through the chamber, a fiber optic collector for receiving the collimated light after transmission through the chamber, a coating of an acid resistant polymeric composition upon at least one fiber end or lens, the polymeric composition in contact with the sample solution within the chamber and having a detectable response to acid concentrations within the range of from about 0.1 Molar to about 16 Molar, a measurer for the response of the polymeric composition in contact with the sample solution, and a comparer of the measured response to predetermined standards whereby the acid molarity of the sample solution within the chamber can be determined. Preferably, a first lens is attached to the end of the fiber optic light source, the first lens adapted to collimate light from the fiber optic light source, and a second lens is attached to the end of the fiber optic collector for focusing the collimated light after transmission through the chamber. 10 figs.

  19. Domoic Acid Epileptic Disease

    PubMed Central

    Ramsdell, John S.; Gulland, Frances M.

    2014-01-01

    Domoic acid epileptic disease is characterized by spontaneous recurrent seizures weeks to months after domoic acid exposure. The potential for this disease was first recognized in a human case study of temporal lobe epilepsy after the 1987 amnesic shellfish-poisoning event in Quebec, and was characterized as a chronic epileptic syndrome in California sea lions through investigation of a series of domoic acid poisoning cases between 1998 and 2006. The sea lion study provided a breadth of insight into clinical presentations, unusual behaviors, brain pathology, and epidemiology. A rat model that replicates key observations of the chronic epileptic syndrome in sea lions has been applied to identify the progression of the epileptic disease state, its relationship to behavioral manifestations, and to define the neural systems involved in these behavioral disorders. Here, we present the concept of domoic acid epileptic disease as a delayed manifestation of domoic acid poisoning and review the state of knowledge for this disease state in affected humans and sea lions. We discuss causative mechanisms and neural underpinnings of disease maturation revealed by the rat model to present the concept for olfactory origin of an epileptic disease; triggered in dendodendritic synapases of the olfactory bulb and maturing in the olfactory cortex. We conclude with updated information on populations at risk, medical diagnosis, treatment, and prognosis. PMID:24663110

  20. Domoic acid epileptic disease.

    PubMed

    Ramsdell, John S; Gulland, Frances M

    2014-03-01

    Domoic acid epileptic disease is characterized by spontaneous recurrent seizures weeks to months after domoic acid exposure. The potential for this disease was first recognized in a human case study of temporal lobe epilepsy after the 1987 amnesic shellfish-poisoning event in Quebec, and was characterized as a chronic epileptic syndrome in California sea lions through investigation of a series of domoic acid poisoning cases between 1998 and 2006. The sea lion study provided a breadth of insight into clinical presentations, unusual behaviors, brain pathology, and epidemiology. A rat model that replicates key observations of the chronic epileptic syndrome in sea lions has been applied to identify the progression of the epileptic disease state, its relationship to behavioral manifestations, and to define the neural systems involved in these behavioral disorders. Here, we present the concept of domoic acid epileptic disease as a delayed manifestation of domoic acid poisoning and review the state of knowledge for this disease state in affected humans and sea lions. We discuss causative mechanisms and neural underpinnings of disease maturation revealed by the rat model to present the concept for olfactory origin of an epileptic disease; triggered in dendodendritic synapases of the olfactory bulb and maturing in the olfactory cortex. We conclude with updated information on populations at risk, medical diagnosis, treatment, and prognosis. PMID:24663110

  1. Optical high acidity sensor

    DOEpatents

    Jorgensen, Betty S.; Nekimken, Howard L.; Carey, W. Patrick; O'Rourke, Patrick E.

    1997-01-01

    An apparatus and method for determining acid concentrations in solutions having acid concentrations of from about 0.1 Molar to about 16 Molar is disclosed. The apparatus includes a chamber for interrogation of the sample solution, a fiber optic light source for passing light transversely through the chamber, a fiber optic collector for receiving the collimated light after transmission through the chamber, a coating of an acid resistant polymeric composition upon at least one fiber end or lens, the polymeric composition in contact with the sample solution within the chamber and having a detectable response to acid concentrations within the range of from about 0.1 Molar to about 16 Molar, a measurer for the response of the polymeric composition in contact with the sample solution, and, a comparer of the measured response to predetermined standards whereby the acid molarity of the sample solution within the chamber can be determined. Preferably, a first lens is attached to the end of the fiber optic light source, the first lens adapted to collimate light from the fiber optic light source, and a second lens is attached to the end of the fiber optic collector for focusing the collimated light after transmission through the chamber.

  2. A Demonstration of Acid Rain

    ERIC Educational Resources Information Center

    Fong, Man Wai

    2004-01-01

    A demonstration showing acid rain formation is described. Oxides of sulfur and nitrogen that result from the burning of fossil fuels are the major pollutants of acid rain. In this demonstration, SO[subscript 2] gas is produced by the burning of matches. An acid-base indicator will show that the dissolved gas turns an aqueous solution acidic.

  3. Oleanolic acid ethanol monosolvate

    PubMed Central

    Froelich, Anna; Gzella, Andrzej K.

    2010-01-01

    Crystals of the title compound (systematic name: 3β-hy­droxy­olean-12-en-28-oic acid ethanol monosolvate), C30H48O3·C2H5OH, were obtained from unsuccessful co-crystallization trials. The asymmetric unit contains two symmetry-independent oleanolic acid mol­ecules, as well as two ethanol solvent mol­ecules. Inter­molecular O—H⋯O hydrogen bonds stabilize the crystal packing. In the oleanolic acid mol­ecules, ring C has a slightly distorted envelope conformation, while rings A, B, D and E adopt chair conformations and rings D and E are cis-fused. Both independent ethanol mol­ecules are orientationally disordered [occupancy ratios of 0.742 (8):0.258 (8) and 0.632 (12):0.368 (12). PMID:21588987

  4. Amino acid analysis.

    PubMed

    Crabb, J W; West, K A; Dodson, W S; Hulmes, J D

    2001-05-01

    Amino acid analysis (AAA) is one of the best methods to quantify peptides and proteins. Two general approaches to quantitative AAA exist, namely, classical postcolumn derivatization following ion-exchange chromatography and precolumn derivatization followed by reversed-phase HPLC (RP-HPLC). Excellent instrumentation and several specific methodologies are available for both approaches, and both have advantages and disadvantages. This unit focuses on picomole-level AAA of peptides and proteins using the most popular precolumn-derivatization method, namely, phenylthiocarbamyl amino acid analysis (PTC-AAA). It is directed primarily toward those interested in establishing the technology with a modest budget. PTC derivatization and analysis conditions are described, and support and alternate protocols describe additional techniques necessary or useful for most any AAA method--e.g., sample preparation, hydrolysis, instrument calibration, data interpretation, and analysis of difficult or unusual residues such as cysteine, tryptophan, phosphoamino acids, and hydroxyproline. PMID:18429107

  5. Acid rain: Controllable?

    NASA Astrophysics Data System (ADS)

    Machta, Lester

    Acid rain is one of a growing number of environmental issues in which impacts are far removed from the source o f the irritants. Those who suffer may differ in geographical area from those who benefit from the activity which releases pollution to the atmosphere. Like the issue concerning the depletion of ozone by manufactured chemicals, the acid rain issue further emphasizes the need for continuing atmospheric chemistry research, a science whose history dates back but a few decades. Examination of the acid rain issue also calls for intimate collaboration of atmospheric scientists with ecologists, biologists, and other scientists, who must advise the geophysicists regarding what chemicals in the environment produce damage, their mode of entry into an ecosystem, and the need to understand acute or chronic impacts.

  6. Acid rain in Asia

    NASA Astrophysics Data System (ADS)

    Bhatti, Neeloo; Streets, David G.; Foell, Wesley K.

    1992-07-01

    Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.

  7. NITRIC ACID PICKLING PROCESS

    DOEpatents

    Boller, E.R.; Eubank, L.D.

    1958-08-19

    An improved process is described for the treatment of metallic uranium surfaces preparatory to being given hot dip coatings. The process consists in first pickling the uraniunn surInce with aqueous 50% to 70% nitric acid, at 60 to 70 deg C, for about 5 minutes, rinsing the acid solution from the uranium article, promptly drying and then passing it through a molten alkali-metal halide flux consisting of 42% LiCl, 53% KCla and 5% NaCl into a molten metal bath consisting of 85 parts by weight of zinc and 15 parts by weight of aluminum

  8. [Nicotinic acid and nicotinamide].

    PubMed

    Kobayashi, M; Shimizu, S

    1999-10-01

    Nicotinic acid and nicotinamide are called niacin. They are the antipellagra vitamin essential to many animals for growth and health. In human being, niacin is believed necessary together with other vitamins for the prevention and cure of pellagra. Niacin is widely distributed in nature; appreciable amounts are found in liver, fish, yeast and cereal grains. Nicotinamide is a precursor of the coenzyme NAD and NADP. Some of the most understood metabolic processes that involve niacin are glycolysis, fatty acid synthesis and respiration. Niacin is also related to the following diseases: Hartnup disease; blue diaper syndrome; tryptophanuria; hydroxykynureninuria; xanthurenic aciduria; Huntington's disease. PMID:10540864

  9. Fatty Acids of Thiobacillus thiooxidans

    PubMed Central

    Levin, Richard A.

    1971-01-01

    Fatty acid spectra were made on Thiobacillus thiooxidans cultures both in the presence and absence of organic compounds. Small additions of glucose or acetate had no significant effect either on growth or fatty acid content. The addition of biotin had no stimulatory effect but did result in slight quantitative changes in the fatty acid spectrum. The predominant fatty acid was a C19 cyclopropane acid. PMID:4945206

  10. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    ERIC Educational Resources Information Center

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  11. Comparison of Buffer Effect of Different Acids During Sandstone Acidizing

    NASA Astrophysics Data System (ADS)

    Umer Shafiq, Mian; Khaled Ben Mahmud, Hisham; Hamid, Mohamed Ali

    2015-04-01

    The most important concern of sandstone matrix acidizing is to increase the formation permeability by removing the silica particles. To accomplish this, the mud acid (HF: HCl) has been utilized successfully for many years to stimulate the sandstone formations, but still it has many complexities. This paper presents the results of laboratory investigations of different acid combinations (HF: HCl, HF: H3PO4 and HF: HCOOH). Hydrofluoric acid and fluoboric acid are used to dissolve clays and feldspar. Phosphoric and formic acids are added as a buffer to maintain the pH of the solution; also it allows the maximum penetration of acid into the core sample. Different tests have been performed on the core samples before and after the acidizing to do the comparative study on the buffer effect of these acids. The analysis consists of permeability, porosity, color change and pH value tests. There is more increase in permeability and porosity while less change in pH when phosphoric and formic acids were used compared to mud acid. From these results it has been found that the buffer effect of phosphoric acid and formic acid is better than hydrochloric acid.

  12. Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

    1992-01-01

    Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

  13. Docosahexaenoic acid and lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina, and brain, and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews dat...

  14. ACID AEROSOL MEASUREMENT WORKSHOP

    EPA Science Inventory

    This report documents the discussion and results of the U.S. EPA Acid Aerosol Measurement Workshop, conducted February 1-3, 1989, in Research Triangle Park, North Carolina. t was held in response to recommendations by the Clean Air Scientific Advisory Committee (CASAC) regarding ...

  15. Acid Rain Classroom Projects.

    ERIC Educational Resources Information Center

    Demchik, Michael J.

    2000-01-01

    Describes a curriculum plan in which students learn about acid rain through instructional media, research and class presentations, lab activities, simulations, design, and design implementation. Describes the simulation activity in detail and includes materials, procedures, instructions, examples, results, and discussion sections. (SAH)

  16. Acid rain bibliography

    SciTech Connect

    Sayers, C.S.

    1983-09-01

    This bibliography identifies 900 citations on various aspects of Acid Rain, covering published bibliographies, books, reports, conference and symposium proceedings, audio visual materials, pamphlets and newsletters. It includes five sections: citations index (complete record of author, title, source, order number); KWIC index; title index; author index; and source index. 900 references.

  17. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Oates-Bockenstedt, Catherine

    1997-01-01

    Details an activity designed to motivate students by incorporating science-related issues into a classroom debate. Includes "The Acid Rain Bill" and "Position Guides" for student roles as committee members, consumers, governors, industry owners, tourism professionals, senators, and debate directors. (DKM)

  18. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Bybee, Rodger; And Others

    1984-01-01

    Describes an activity which provides opportunities for role-playing as industrialists, ecologists, and government officials. The activity involves forming an international commission on acid rain, taking testimony, and, based on the testimony, making recommendations to governments on specific ways to solve the problem. Includes suggestions for…

  19. The Acid Rain Game.

    ERIC Educational Resources Information Center

    Rakow, Steven J.; Glenn, Allen

    1982-01-01

    Provides rationale for and description of an acid rain game (designed for two players), a problem-solving model for elementary students. Although complete instructions are provided, including a copy of the game board, the game is also available for Apple II microcomputers. Information for the computer program is available from the author.…

  20. Acid Rain Investigations.

    ERIC Educational Resources Information Center

    Hugo, John C.

    1992-01-01

    Presents an activity in which students investigate the formation of solid ammonium chloride aerosol particles to help students better understand the concept of acid rain. Provides activity objectives, procedures, sample data, clean-up instructions, and questions and answers to help interpret the data. (MDH)

  1. Brain amino acid sensing.

    PubMed

    Tsurugizawa, T; Uneyama, H; Torii, K

    2014-09-01

    The 20 different amino acids, in blood as well as in the brain, are strictly maintained at the same levels throughout the day, regardless of food intake. Gastric vagal afferents only respond to free glutamate and sugars, providing recognition of food intake and initiating digestion. Metabolic control of amino acid homeostasis and diet-induced thermogenesis is triggered by this glutamate signalling in the stomach through the gut-brain axis. Rats chronically fed high-sugar and high-fat diets do not develop obesity when a 1% (w/v) monosodium glutamate (MSG) solution is available in a choice paradigm. Deficiency of the essential amino acid lysine (Lys) induced a plasticity in rats in response to Lys. This result shows how the body is able to identify deficient nutrients to maintain homeostasis. This plastic effect is induced by activin A activity in the brain, particularly in certain neurons in the lateral hypothalamic area (LHA) which is the centre for amino acid homeostasis and appetite. These neurons respond to glutamate signalling in the oral cavity by which umami taste is perceived. They play a quantitative role in regulating ingestion of deficient nutrients, thereby leading to a healthier life. After recovery from malnutrition, rats prefer MSG solutions, which serve as biomarkers for protein nutrition. PMID:25200295

  2. Targeting tumor acidity

    NASA Astrophysics Data System (ADS)

    Reshetnyak, Yana K.; Engelman, Donald M.; Andreev, Oleg A.

    2012-02-01

    One of the main features of solid tumors is extracellular acidity, which correlates with tumor aggressiveness and metastatic potential. We introduced novel approach in targeting of acidic tumors, and translocation of cell-impermeable cargo molecules across cellular membrane. Our approach is based on main principle of insertion and folding of a polypeptide in lipid bilayer of membrane. We have identified family of pH Low Insertion Peptides (pHLIPs), which are capable spontaneous insertion and folding in membrane at mild acidic conditions. The affinity of peptides of pHLIP family to membrane at low pH is several times higher than at neutral pH. The process of peptides folding occurs within milliseconds. The energy released in a result of folding (about 2 kcal/mol) could be used to move polar cargo across a membrane, which is a novel concept in drug delivery. pHLIP peptides could be considered as a pH-sensitive single peptide molecular transporters and conjugated with imaging probes for fluorescence, MR, PET and SPECT imaging, they represent a novel in vivo marker of acidity. The work is supported by NIH grants CA133890 and GM073857 to OAA, DME, YRK.

  3. Synthesis of (+)-Coronafacic Acid

    PubMed Central

    Taber, Douglass F.; Sheth, Ritesh B.; Tian, Weiwei

    2009-01-01

    An enantioselective synthesis of (+)-coronafacic acid has been achieved. Rhodium catalyzed cyclization of an α-diazoester provided the intermediate cyclopentanone in high enantiomeric purity. Subsequent Fe-mediated cyclocarbonylation of a derived alkenyl cyclopropane gave a bicyclic enone, that then was hydrogenated and carried on to the natural product. PMID:19231870

  4. Plant fatty acid hydroxylase

    DOEpatents

    Somerville, Chris; van de Loo, Frank

    2000-01-01

    The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

  5. Spermatotoxicity of dichloroacetic acid

    EPA Science Inventory

    The testicular toxicity of dichloroacetic acid (DCA), a disinfection byproduct of drinking water, was evaluated in adult male rats given both single and multiple (up to 14 d) oral doses. Delayed spermiation and altered resorption of residual bodies were observed in rats given sin...

  6. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    SciTech Connect

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert

    2010-05-03

    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  7. Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

    DOEpatents

    Moens, Luc

    2003-06-24

    A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

  8. Photostabilization of ascorbic acid with citric acid, tartaric acid and boric acid in cream formulations.

    PubMed

    Ahmad, I; Ali Sheraz, M; Ahmed, S; Shad, Z; Vaid, F H M

    2012-06-01

    This study involves the evaluation of the effect of certain stabilizers, that is, citric acid (CT), tartaric acid (TA) and boric acid (BA) on the degradation of ascorbic acid (AH(2) ) in oil-in-water cream formulations exposed to the UV light and stored in the dark. The apparent first-order rate constants (0.34-0.95 × 10(-3) min(-1) in light, 0.38-1.24 × 10(-2) day(-1) in dark) for the degradation reactions in the presence of the stabilizers have been determined. These rate constants have been used to derive the second-order rate constants (0.26-1.45 × 10(-2) M(-1) min(-1) in light, 3.75-8.50 × 10(-3) M(-1) day(-1) in dark) for the interaction of AH(2) and the individual stabilizers. These stabilizers are effective in causing the inhibition of the rate of degradation of AH(2) both in the light and in the dark. The inhibitory effect of the stabilizers is in the order of CT > TA > BA. The rate of degradation of AH(2) in the presence of these stabilizers in the light is about 120 times higher than that in the dark. This could be explained on the basis of the deactivation of AH(2) -excited triplet state by CT and TA and by the inhibition of AH(2) degradation through complex formation with BA. AH(2) leads to the formation of dehydroascorbic acid (A) by chemical and photooxidation in cream formulations. PMID:22296174

  9. Fatty acid-producing hosts

    SciTech Connect

    Pfleger, Brian F; Lennen, Rebecca M

    2013-12-31

    Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at 37.degree. C. Methods of producing a fatty acid product comprising culturing such hosts at 37.degree. C. are also described.

  10. [Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

    PubMed

    Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

    2016-03-01

    Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis. PMID:27349116

  11. Circulating folic acid in plasma: relation to folic acid fortification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The implementation of folic acid fortification in the United States has resulted in unprecedented amounts of this synthetic form of folate in the American diet. Folic acid in circulation may be a useful measure of physiologic exposure to synthetic folic acid, and there is a potential for elevated co...

  12. College Chemistry Students' Mental Models of Acids and Acid Strength

    ERIC Educational Resources Information Center

    McClary, LaKeisha; Talanquer, Vicente

    2011-01-01

    The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research…

  13. NAPAP (National Acid Precipitation Assessment Program) results on acid rain

    SciTech Connect

    Not Available

    1990-06-01

    The National Acid Precipitation Assessment Program (NAPAP) was mandated by Congress in 1980 to study the effects of acid rain. The results of 10 years of research on the effect of acid deposition and ozone on forests, particularly high elevation spruce and fir, southern pines, eastern hardwoods and western conifers, will be published this year.

  14. Acid Earth--The Global Threat of Acid Pollution.

    ERIC Educational Resources Information Center

    McCormick, John

    Acid pollution is a major international problem, but the debate it has elicited has often clouded the distinction between myth and facts. This publication attempts to concerning the acid pollution situation. This publication attempts to identify available facts. It is the first global review of the problem of acid pollution and the first to…

  15. Industrial ecotoxicology "acid rain".

    PubMed

    Astolfi, E; Gotelli, C; Higa, J

    1986-01-01

    The acid rain phenomenon was studied in the province of Cordoba, Argentina. This study, based on a previously outlined framework, determined the anthropogenic origin of the low pH due to the presence of industrial hydrochloric acid wastage. This industrial ecotoxicological phenomenon seriously affected the forest wealth, causing a great defoliation of trees and shrubs, with a lower effect on crops. A survey on its effects on human beings has not been carried out, but considering the corrosion caused to different metals and its denouncing biocide effect on plants and animals, we should expect to find some kind of harm to the health of the workers involved or others engaged in farming, and even to those who are far away from the polluting agent. PMID:3758667

  16. [Progress in glucaric acid].

    PubMed

    Qiu, Yuying; Fang, Fang; Du, Guocheng; Chen, Jian

    2015-04-01

    Glucaric acid (GA) is derived from glucose and commonly used in chemical industry. It is also considered as one of the "Top value-added chemicals from biomass" as carbohydrate monomers to produce various synthetic polymers and bioenergy. The demand for GA in food manufacture is increasing. GA has also attracted public attentions due to its therapeutic uses such as regulating hormones, increasing the immune function and reducing the risks of cancers. Currently GA is produced by chemical oxidation. Research on production of GA via microbial synthesis is still at preliminary stage. We reviewed the advances of glucaric acid applications, preparation and quantification methods. The prospects on production of GA by microbial fermentation were also discussed. PMID:26380405

  17. Acid hydrolysis of cellulose

    SciTech Connect

    Salazar, H.

    1980-12-01

    One of the alternatives to increase world production of etha nol is by the hydrolysis of cellulose content of agricultural residues. Studies have been made on the types of hydrolysis: enzimatic and acid. Data obtained from the sulphuric acid hydrolysis of cellulose showed that this process proceed in two steps, with a yield of approximately 95% glucose. Because of increases in cost of alternatives resources, the high demand of the product and the more economic production of ethanol from cellulose materials, it is certain that this technology will be implemented in the future. At the same time further studies on the disposal and reuse of the by-products of this production must be undertaken.

  18. Eucomic acid methanol monosolvate

    PubMed Central

    Li, Guo-Qiang; Li, Yao-Lan; Wang, Guo-Cai; Liang, Zhi-Hong; Jiang, Ren-Wang

    2011-01-01

    In the crystal structure of the title compound [systematic name: 2-hy­droxy-2-(4-hy­droxy­benz­yl)butane­dioic acid methanol monosolvate], C11H12O6·CH3OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter­molecular O—H⋯O hydrogen-bonding inter­actions involving the hy­droxy and carb­oxy­lic acid groups and the methanol solvent mol­ecule give a three-dimensional structure. PMID:22091200

  19. (Radioiodinated free fatty acids)

    SciTech Connect

    Knapp, Jr., F. F.

    1987-12-11

    The traveler participated in the Second International Workshop on Radioiodinated Free Fatty Acids in Amsterdam, The Netherlands where he presented an invited paper describing the pioneering work at the Oak Ridge National Laboratory (ORNL) involving the design, development and testing of new radioiodinated methyl-branched fatty acids for evaluation of heart disease. He also chaired a technical session on the testing of new agents in various in vitro and in vivo systems. He also visited the Institute for Clinical and Experimental Nuclear Medicine in Bonn, West Germany, to review, discuss, plan and coordinate collaborative investigations with that institution. In addition, he visited the Cyclotron Research Center in Liege, Belgium, to discuss continuing collaborative studies with the Osmium-191/Iridium-191m radionuclide generator system, and to complete manuscripts and plan future studies.

  20. Tunnelling in carbonic acid.

    PubMed

    Wagner, J Philipp; Reisenauer, Hans Peter; Hirvonen, Viivi; Wu, Chia-Hua; Tyberg, Joseph L; Allen, Wesley D; Schreiner, Peter R

    2016-06-14

    The cis,trans-conformer of carbonic acid (H2CO3), generated by near-infrared radiation, undergoes an unreported quantum mechanical tunnelling rotamerization with half-lives in cryogenic matrices of 4-20 h, depending on temperature and host material. First-principles quantum chemistry at high levels of theory gives a tunnelling half-life of about 1 h, quite near those measured for the fastest rotamerizations. PMID:27248671

  1. Optimize acid gas removal

    SciTech Connect

    Nicholas, D.M.; Wilkins, J.T.

    1983-09-01

    Innovative design of physical solvent plants for acid gas removal can materially reduce both installation and operating costs. A review of the design considerations for one physical solvent process (Selexol) points to numerous arrangements for potential improvement. These are evaluated for a specific case in four combinations that identify an optimum for the case in question but, more importantly, illustrate the mechanism for use for such optimization elsewhere.

  2. Studies on terreic acid.

    PubMed

    Yamamoto, H; Moriyama, K; Jinnouchi, H; Yagishita, K

    1980-03-01

    It was found that Aspergillus sp. No. Y-8980 which was isolated from a soil sample collected at Yoron Island in Kagoshima Prefecture belonged to Aspergillus terreus group by morphological observation. The active substance produced by the strain was obtained with a high yield in sucrose-yeast extract medium and extracted by chloroform, ethyl acetate and n-butanol at pH 2.4 approximately 2.6 from the culture broth. The substance was crystallized from chloroform and ethyl acetate after charcoal treatment of the crude crystal. From various physico-chemical properties, it was found that the substance was identical to terreic acid. Terreic acid showed MICs of 25 approximately 100 mcg/ml, 12.5 mcg/ml and 50 mcg/ml against Gram-positive and Gram-negative bacteria, Xanthomonas oryzae and Xanthomonas citri, respectively, but it did not control Pseudomonas, fungi and yeast. The LD50 was 75 mg/kg i.p. and i.v. in mice. With regards to the anti-tumor effect, the morphological degeneration on HeLa cells (human carcinoma cells) was observed in the concentrations of more than 6.25 mcg/ml of terreic acid. An increase of body weight of mice caused by Ehrlich ascites carcinoma cells was not definitely observed by the daily administration of 150 mcg of terreic acid per mouse for 8 consecutive days. Above showed the enough survival effect in dd mice implanted with Ehrlich ascites carcinoma cells, and the effect also was demonstrated by anatomies of mice. PMID:7190624

  3. The Prebiotic Synthesis of Ethylenediamine Monoacetic Acid, The Repeating Unit of Peptide Nucleic Acids

    NASA Technical Reports Server (NTRS)

    Nelson, Kevin E.; Miller, Stanley L.

    1992-01-01

    The polymerization of ribonucleic acids or their precursors constitutes an important event in prebiotic chemistry. The various problems using ribonucleotides to make RNA suggest that there may have been a precursor. An attractive possibility are the peptide nucleic acids (PNA). PNAs are nucleotide analogs that make use of a polymer of ethylenediamine monoacetic acid (EDMA or 2-amninoethyl glycine) with the bases attached by an acetic acid. EDMA is an especially attractive alternative to the ribose phosphate or deoxyribose phosphate backbone because it contains no chiral centers and is potentially prebiotic, but there is no reported prebiotic synthesis. We have synthesized both EDMA and ethylenediamine diacetic acid (EDDA) from the prebiotic compounds ethylenediamine, formaldehyde, and hydrogen cyanide. The yields of EDMA range from 11 to 79% along with some sEDDA and uEDDA. These reactions work with concentrations of 10(exp -1)M and as low as 10(exp -4)M, and the reaction is likely to be effective at even lower concentrations. Ethylenediamine is a likely prebiotic compound, but it has not yet been demonstrated, although compounds such as ethanolamine and cysteamine have been proven to be prebiotic. Under neutral pH and heating at l00 C, EDMA is converted to the lactam, monoketopiperazine (MKP). The cyclization occurs and has an approximate ratio of MKP/EDMA = 3 at equilibrium. We have measured the solubilities of EDMA center dot H20 as 6.4 m, EDMA center dot HCl center dot H20 as 13.7 m, and EDMA center dot 2HCl center dot H20 as 3.4 m. These syntheses together with the high solubility of EDMA suggest that EDMA would concentrate in drying lagoons and might efficiently form polymers. Given the instability of ribose and the poor polymerizability of nucleotides, the prebiotic presence of EDMA and the possibility of its polymerization raises the possibility that PNAs are the progenitors of present day nucleic acids. A pre-RNA world may have existed in which PNAs or

  4. Perfluorooctanoic acid and environmental risks

    EPA Science Inventory

    Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acids (PFAA) family of chemicals, which consist of a carbon backbone typically four to fourteen carbons in length and a charged functional moiety.

  5. Folic Acid Questions and Answers

    MedlinePlus

    ... swallow large pills. How can I take a vitamin with folic acid? A : These days, multivitamins with folic acid come in chewable chocolate or fruit flavors, liquids, and large oval or smaller round ...

  6. Pantothenic acid (Vitamin B5)

    MedlinePlus

    Pantothenic acid is a vitamin, also known as vitamin B5. It is widely found in both plants and animals ... Vitamin B5 is commercially available as D-pantothenic acid, as well as dexpanthenol and calcium pantothenate, which ...

  7. Bile acid sequestrants for cholesterol

    MedlinePlus

    Bile acid sequestrants are medicines that help lower your LDL (bad) cholesterol . Too much cholesterol in your blood can ... block them. These medicines work by blocking bile acid in your stomach from being absorbed in your ...

  8. Omega-3 fatty acids (image)

    MedlinePlus

    Omega-3 fatty acids are a form of polyunsaturated fat that the body derives from food. Omega-3s (and omega-6s) are known as essential fatty acids (EFAs) because they are important for good health. ...

  9. Pantothenic acid (Vitamin B5)

    MedlinePlus

    ... D-pantothenic acid, as well as dexpanthenol and calcium pantothenate, which are chemicals made in the lab from ... Early research suggests that pantothenic acid (given as calcium pantothenate) does not reduce symptoms of osteoarthritis. Recovery after ...

  10. Amino acid imbalance in cystinuria

    PubMed Central

    Asatoor, A. M.; Freedman, P. S.; Gabriel, J. R. T.; Milne, M. D.; Prosser, D. I.; Roberts, J. T.; Willoughby, C. P.

    1974-01-01

    After oral ingestion of a free amino acid mixture by three cystinuric patients, plasma increments of lysine and arginine were lower and those of many other amino acids were significantly higher than those found in control subjects. Similar results were obtained in control subjects after amino acid imbalance had been artificially induced by the omission of cystine, lysine, and arginine from the amino acid mixture. Especially high increments of alanine and proline provided the best evidence of amino acid imbalance caused by a temporary lysine and, to a lesser extent, arginine and cystine deficit. No such amino acid imbalance was found to occur in the cystinuric patients after ingestion of whole protein, indicating that absorption of oligopeptides produced by protein digestion provided a balanced physiological serum amino acid increment. This is considered to explain the lack of any unequivocal nutritional deficit in cystinuric patients despite poor absorption of the essential free amino acid, lysine. PMID:4411931

  11. Immunomodulatory spherical nucleic acids

    PubMed Central

    Radovic-Moreno, Aleksandar F.; Chernyak, Natalia; Mader, Christopher C.; Nallagatla, Subbarao; Kang, Richard S.; Hao, Liangliang; Walker, David A.; Halo, Tiffany L.; Merkel, Timothy J.; Rische, Clayton H.; Anantatmula, Sagar; Burkhart, Merideth; Mirkin, Chad A.; Gryaznov, Sergei M.

    2015-01-01

    Immunomodulatory nucleic acids have extraordinary promise for treating disease, yet clinical progress has been limited by a lack of tools to safely increase activity in patients. Immunomodulatory nucleic acids act by agonizing or antagonizing endosomal toll-like receptors (TLR3, TLR7/8, and TLR9), proteins involved in innate immune signaling. Immunomodulatory spherical nucleic acids (SNAs) that stimulate (immunostimulatory, IS-SNA) or regulate (immunoregulatory, IR-SNA) immunity by engaging TLRs have been designed, synthesized, and characterized. Compared with free oligonucleotides, IS-SNAs exhibit up to 80-fold increases in potency, 700-fold higher antibody titers, 400-fold higher cellular responses to a model antigen, and improved treatment of mice with lymphomas. IR-SNAs exhibit up to eightfold increases in potency and 30% greater reduction in fibrosis score in mice with nonalcoholic steatohepatitis (NASH). Given the clinical potential of SNAs due to their potency, defined chemical nature, and good tolerability, SNAs are attractive new modalities for developing immunotherapies. PMID:25775582

  12. Cannabinoid acids analysis.

    PubMed

    Lercker, G; Bocci, F; Frega, N; Bortolomeazzi, R

    1992-03-01

    The cannabinoid pattern of vegetable preparations from Cannabis sativa (hashish, marijuana) allows to recognize the phenotype of the plants, to be used as drug or for fiber. Cannabinoid determination by analytical point of view has represented some problems caused by the complex composition of the hexane extract. Capillary gas chromatography of the hexane extracts of vegetable samples, shows the presence of rather polar constituents that eluted, with noticeable interactions, only on polar phase. The compounds can be methylated by diazomethane and silanized (TMS) by silylating reagents. The methyl and methyl-TMS derivatives are analyzed by high resolution gas chromatography (HRGC) and by gas chromatography-mass spectrometry (GC-MS). The identification of the compounds shows their nature of cannabinoid acids, which the main by quantitative point of view results the cannabidiolic acid (CBDA). It is known that the cannabinoid acids are thermally unstable and are transformed in the corresponding cannabinoids by decarboxilation. This is of interest in forensic analysis with the aim to establish the total amount of THC in the Cannabis preparations, as the active component. PMID:1503600

  13. Acid rain: Reign of controversy

    SciTech Connect

    Kahan, A.M.

    1986-01-01

    Acid Rain is a primer on the science and politics of acid rain. Several introductory chapters describe in simple terms the relevant principles of water chemistry, soil chemistry, and plant physiology and discuss the demonstrated or postulated effects of acid rain on fresh waters and forests as well as on statuary and other exposed objects. There follow discussions on the economic and social implications of acid rain (for example, possible health effects) and on the sources, transport, and distribution of air pollutants.

  14. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C. Judson; Poole, Loree J.

    1995-01-01

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine.

  15. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C.J.; Poole, L.J.

    1995-05-02

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine. 10 figs.

  16. An Umbrella for Acid Rain.

    ERIC Educational Resources Information Center

    Randal, Judith

    1979-01-01

    The Environmental Protection Agency has awarded several grants to study effects of and possible solutions to the problem of "acid rain"; pollution from atmospheric nitric and sulfuric acids. The research program is administered through North Carolina State University at Raleigh and will focus on biological effects of acid rain. (JMF)

  17. BACTERIAL OXIDATION OF DIPICOLINIC ACID

    PubMed Central

    Kobayashi, Yasuo; Arima, Kei

    1962-01-01

    Kobayashi, Yasuo (University of Tokyo, Tokyo, Japan) and Kei Arima. Bacterial oxidation of dipicolinic acid. II. Identification of α-ketoglutaric acid and 3-hydroxydipicolinic acid and some properties of cell-free extracts. J. Bacteriol. 84:765–771. 1962—When a dipicolinic acid (DPA)-decomposing bacterium, Achromobacter strain 1–2, was incubated at 30 C with shaking in a DPA solution containing 10−3m arsenite, a keto acid was accumulated. The 2,4-dinitrophenylhydrazone of this acid was synthesized and identified as α-ketoglutaric acid by paper chromatography, visible absorption spectrum, infrared analysis, elemental analysis, and mixed melting point. During this incubation, oxalic acid equivalent to the consumed dipicolinic acid was produced. A fluorescent material was also isolated from culture fluid and identified as 3-hydroxydipicolinic acid by paper chromatography and the ultraviolet absorption spectrum. Further, cell-free extracts were prepared by sonic oscillation. Ferrous ion and a reduced di- or triphosphopyridine nucleotide-generating system were proven to be required for enzymic oxidation of DPA. And 3-hydroxydipicolinic acid was also oxidized by this preparation. From the results obtained, a possible metabolic pathway of dipicolinic acid was proposed. PMID:14033954

  18. Pantothenic acid biosynthesis in zymomonas

    SciTech Connect

    Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V.

    2014-07-01

    Zymomonas is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium. Zymomonas strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

  19. Scientists Puzzle Over Acid Rain

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Reports on a growing concern over increased acidity in atmospheric percipitation. Explores possible causes of the increased acidity, identifies chemical components of precipitation in various parts of the world, and presents environmental changes that might be attributed to the acidity. (GS)

  20. Serum Uric Acid in Smokers

    PubMed Central

    Hanna, Bassam E.; Hamed, Jamal M.; Touhala, Luma M.

    2008-01-01

    Objectives To demonstrate the possible effect of smoking on serum uric acid. Methods Subjects enrolled in study were divided into two groups; nonsmokers and smokers, each with 60 male volunteers of the same social class and dietary habit without history of alcohol consumption, diabetes mellitus, hyperuricemia and gout, renal, joint, lung or heart diseases. Fasting blood and random urine samples were obtained from both groups for measurement of uric acid and creatinine. Calculation of both urine uric acid/urine creatinine ratio and fraction excretion of uric acid were done. The results were statistically evaluated by standard statistical methods. Results No significant differences in the age, serum creatinine, spot urine uric acid/urine creatinine ratio and fraction excretion of uric acid between the two groups, serum uric acid was significantly lower in smokers. In smokers there was significant negative correlation of smoking status (average number of cigarette smoked/day, duration of smoking and cumulative amount of smoking) with serum uric acid. Conclusion After exclusion of other factors affecting uric acid level, the significant low serum uric acid level in smokers was attributed to reduce endogenous production as a result of chronic exposure to cigarette smoke that is a significant source of oxidative stress. As this reduction is proportionate with smoking status and predisposes to cardiovascular disease, it is, therefore, recommended for smokers to stop or reduce smoking and introduce serum uric acid estimation as routine test since its cheap and simple to reflect their antioxidant level. Keywords Smokers; Uric acid; CVD. PMID:22334840

  1. Experimental study of the hydrothermal reactivity of organic acids and acid anions: II. Acetic acid, acetate, and valeric acid

    NASA Astrophysics Data System (ADS)

    McCollom, Thomas M.; Seewald, Jeffrey S.

    2003-10-01

    Organic acids and acid anions occur in substantial concentrations in many aqueous geologic fluids and are thought to take part in a variety of geochemical processes ranging from the transport of metals in ore-forming fluids to the formation of natural gas to serving as a metabolic energy source for microbes in subsurface habitats. The widespread occurrence of organic acids and their potential role in diverse geologic processes has led to numerous experimental studies of their thermal stability, yet there remain substantial gaps in our knowledge of the factors that control the rates and reaction pathways for the decomposition of these compounds under geologic conditions. In order to address some of these uncertainties, a series of laboratory experiments were conducted to examine the behavior of organic acids and acid anions under hydrothermal conditions in the presence of minerals. Reported here are results of experiments where aqueous solutions of acetic acid, sodium acetate, or valeric acid ( n-pentanoic acid) were heated at 325°C, 350 bars in the presence of the mineral assemblages hematite + magnetite + pyrite, pyrite + pyrrhotite + magnetite, and hematite + magnetite. The results indicate that aqueous acetic acid and acetate decompose by a combination of two reaction pathways: decarboxylation and oxidation. Both reactions are promoted by minerals, with hematite catalyzing the oxidation reaction while magnetite catalyzes decarboxylation. The oxidation reaction is much faster, so that oxidation dominates the decomposition of acetic acid and acetate when hematite is present. In contrast to previous reports that acetate decomposed more slowly than acetic acid, we found that acetate decomposed at slightly faster rates than the acid in the presence of minerals. Although longer-chain monocarboxylic acids are generally thought to decompose by decarboxylation, valeric acid appeared to decompose primarily by "deformylation" to 1-butene plus formic acid. Subsequent

  2. Role of acid diffusion in matrix acidizing of carbonates

    SciTech Connect

    Hoefner, M.L.; Fogler, H.S.; Stenius, P.; Sjoblom, J.

    1987-02-01

    To increase the efficiency of matrix treatments in carbonates, a new type of retarded acid-in-oil microemulsion system has ben developed. The microemulsion is of low viscosity but can exhibit acid diffusion rates two orders of magnitude lower than aqueous HCl. Decreased acid diffusion delays spending and allows live acid to penetrate the rock matrix more uniformly and to greater distances. Coreflood results show that the microemulsion can stimulate cores in fewer PV's and under conditions of low injection rates where aqueous HCl fails completely. The microemulsion could also conceivably increase acid penetration along any natural fractures and fissures that may be present, thus increasing acidizing efficiency in this type of treatment. The relationship between the acid diffusion rate and the ability of the fluid to matrix-stimulate limestone is investigated.

  3. Composition for nucleic acid sequencing

    DOEpatents

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2008-08-26

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  4. Evolution of rosmarinic acid biosynthesis.

    PubMed

    Petersen, Maike; Abdullah, Yana; Benner, Johannes; Eberle, David; Gehlen, Katja; Hücherig, Stephanie; Janiak, Verena; Kim, Kyung Hee; Sander, Marion; Weitzel, Corinna; Wolters, Stefan

    2009-01-01

    Rosmarinic acid and chlorogenic acid are caffeic acid esters widely found in the plant kingdom and presumably accumulated as defense compounds. In a survey, more than 240 plant species have been screened for the presence of rosmarinic and chlorogenic acids. Several rosmarinic acid-containing species have been detected. The rosmarinic acid accumulation in species of the Marantaceae has not been known before. Rosmarinic acid is found in hornworts, in the fern family Blechnaceae and in species of several orders of mono- and dicotyledonous angiosperms. The biosyntheses of caffeoylshikimate, chlorogenic acid and rosmarinic acid use 4-coumaroyl-CoA from the general phenylpropanoid pathway as hydroxycinnamoyl donor. The hydroxycinnamoyl acceptor substrate comes from the shikimate pathway: shikimic acid, quinic acid and hydroxyphenyllactic acid derived from l-tyrosine. Similar steps are involved in the biosyntheses of rosmarinic, chlorogenic and caffeoylshikimic acids: the transfer of the 4-coumaroyl moiety to an acceptor molecule by a hydroxycinnamoyltransferase from the BAHD acyltransferase family and the meta-hydroxylation of the 4-coumaroyl moiety in the ester by a cytochrome P450 monooxygenase from the CYP98A family. The hydroxycinnamoyltransferases as well as the meta-hydroxylases show high sequence similarities and thus seem to be closely related. The hydroxycinnamoyltransferase and CYP98A14 from Coleus blumei (Lamiaceae) are nevertheless specific for substrates involved in RA biosynthesis showing an evolutionary diversification in phenolic ester metabolism. Our current view is that only a few enzymes had to be "invented" for rosmarinic acid biosynthesis probably on the basis of genes needed for the formation of chlorogenic and caffeoylshikimic acid while further biosynthetic steps might have been recruited from phenylpropanoid metabolism, tocopherol/plastoquinone biosynthesis and photorespiration. PMID:19560175

  5. The politics of acid rain

    SciTech Connect

    Wilcher, M.E. )

    1989-01-01

    This work examines and compares the acid rain policies through the different political systems of Canada, Great Britain and the United States. Because the flow of acid rain can transcend national boundaries, acid rain has become a crucial international problem. According to the author, because of differences in governmental institutions and structure, the extent of governmental intervention in the industrial economy, the degree of reliance on coal for power generation, and the extent of acid rain damage, national responses to the acid rain problem have varied.

  6. Invasive cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann D.; Dahlberg, James E.

    1999-01-01

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  7. Invasive cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann D.; Dahlberg, James E.

    2002-01-01

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  8. Tested Demonstrations: Color Oscillations in the Formic Acid-Nitric Acid-Sulfuric Acid System.

    ERIC Educational Resources Information Center

    Raw, C. J. G.; And Others

    1983-01-01

    Presented are procedures for demonstrating the production of color oscillations when nitric acid is added to a formic acid/concentrated sulfuric acid mixture. Because of safety considerations, "Super-8" home movie of the color changes was found to be satisfactory for demonstration purposes. (JN)

  9. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-11-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids and quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (< 0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanic emissions.

  10. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-07-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids to quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (<0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanics.

  11. Twinning of dodecanedicarboxylic acid

    NASA Technical Reports Server (NTRS)

    Sen, R.; Wilcox, W. R.

    1986-01-01

    Twinning of 1,10-dodecanedicarboxyl acid (DDA) was observed in 0.1 mm thick films with a polarizing microscope. Twins originated from polycrystalline regions which tended to nucleate on twin faces, and terminated by intersection gone another. Twinning increased dramatically with addition of organic compounds with a similar molecular size and shape. Increasing the freezing rate, increasing the temperature gradient, and addition of silica particles increased twinning. It is proposed that twins nucleate with polycrystals and sometimes anneal out before they become observable. The impurities may enhance twinning either by lowering the twin energy or by adsorbing on growing faces.

  12. Synthesis of amino acids

    DOEpatents

    Davis, J.W. Jr.

    1979-09-21

    A method is described for synthesizing amino acids preceding through novel intermediates of the formulas: R/sub 1/R/sub 2/C(OSOC1)CN, R/sub 1/R/sub 2/C(C1)CN and (R/sub 1/R/sub 2/C(CN)O)/sub 2/SO wherein R/sub 1/ and R/sub 2/ are each selected from hydrogen and monovalent hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art.

  13. Controlling acid rain

    SciTech Connect

    Cannon, J.S.

    1987-01-01

    This book examines recent transfer of electric power among 48 states and present evidence of significant transfers of electric power from so-called ''perpetrator'' to ''victim'' states. The book compares the efforts of several midwestern and northeastern states during the 1970's to control the sulfur dioxide (SO/sub 2/) emissions causing acid rain. The report includes utility and government data on electricity production and sales, on purchase of out-of-state electricity, and on coal use and sulfur dioxide emissions, state by state, for 48 states.

  14. Cryoprotection from lipoteichoic acid

    NASA Astrophysics Data System (ADS)

    Rice, Charles V.; Middaugh, Amy; Wickham, Jason R.; Friedline, Anthony; Thomas, Kieth J.; Johnson, Karen; Zachariah, Malcolm; Garimella, Ravindranth

    2012-10-01

    Numerous chemical additives lower the freezing point of water, but life at sub-zero temperatures is sustained by a limited number of biological cryoprotectants. Antifreeze proteins in fish, plants, and insects provide protection to a few degrees below freezing. Microbes have been found to survive at even lower temperatures, and with a few exceptions, antifreeze proteins are missing. Survival has been attributed to external factors, such as the high salt concentration of brine veins and adhesion to particulates or ice crystal defects. We have discovered an endogenous cryoprotectant in the cell wall of bacteria, lipoteichoic acid biopolymers. Adding 1% LTA to bacteria cultures immediately prior to freezing provides 50% survival rate, similar to the results obtained with 1% glycerol. In the absence of an additive, bacterial survival is negligible as measured with the resazurin cell viability assay. The mode of action for LTA cryoprotection is unknown. With a molecular weight of 3-5 kDa, it is unlikely to enter the cell cytoplasm. Our observations suggest that teichoic acids could provide a shell of liquid water around biofilms and planktonic bacteria, removing the need for brine veins to prevent bacterial freezing.

  15. Nucleic acid detection methods

    DOEpatents

    Smith, C.L.; Yaar, R.; Szafranski, P.; Cantor, C.R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3{prime}-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated. 18 figs.

  16. Nucleic Acid Detection Methods

    DOEpatents

    Smith, Cassandra L.; Yaar, Ron; Szafranski, Przemyslaw; Cantor, Charles R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3'-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated.

  17. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-01-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  18. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Astrophysics Data System (ADS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-05-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1 - 3 × 10-4 Torr H2O and 1 - 2.5 × 10-6 Torr HNO3) and subjected to cooling and heating cycles. FTIR spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  19. Interaction of silicic acid with sulfurous acid scale inhibitor

    SciTech Connect

    Gallup, D.L.

    1997-12-31

    The solubility of amorphous silica and the inhibition of silica polymerization in the presence of sulfurous acid and sulfite salts has been investigated to 260{degrees}C. Investigations of inhibition of silica scaling from geothermal brines by sulfurous acid have produced unusual results. Bisulfite/sulfite increases amorphous silica solubility by {open_quotes}salting in{close_quotes} effects resulting from apparent complexation. Silica-sulfite complexes are postulated to form via hydrogen bonding, and appear to be much stronger than silica-sulfate complexes. Treatment of brines with sulfurous acid inhibits silica scaling by (1) retarding the kinetics of silicic acid polymerization, and (2) forming soluble sulfito-silicate complexes. Sulfurous acid offers several advantages over sulfuric acid in controlling scale deposition-reduced corrosion potential, reduced by-product scale formation potential, oxygen scavenging and inhibition of certain metal silicate scales.

  20. Determination of benzoic acid, chlorobenzoic acids and chlorendic acid in water

    SciTech Connect

    Dietz, E.A.; Cortellucci, N.J.; Singley, K.F. )

    1993-01-01

    To characterize and conduct treatment studies of a landfill leachate an analysis procedure was required to determine concentrations of benzoic acid, the three isomers of chlorobenzoic acid and chlorendic acid. The title compounds were isolated from acidified (pH 1) water by extraction with methyl t-butyl ether. Analytes were concentrated by back-extracting the ether with 0.1 N sodium hydroxide which was separated and acidified. This solution was analyzed by C[sub 18] reversed-phase HPLC with water/acetonitrile/acetic acid eluent and UV detection at 222 nm. The method has detection limits of 200 [mu]g/L for chlorendic acid and 100 [mu]g/L for benzoic acid and each isomer of chlorobenzoic acid. Validation studies with water which was fortified with the analytes at concentrations ranging from one to ten times detection limits resulted in average recoveries of >95%.

  1. Acid rain: Rhetoric and reality

    SciTech Connect

    Park, C.C.

    1987-01-01

    Acid rain is now one of the most serious environmental problems in developed countries. Emissions and fallout were previously extremely localized, but since the introduction of tall stacks policies in both Britain and the US - pardoxically to disperse particulate pollutants and hence reduce local damage - emissions are now lifted into the upper air currents and carried long distances downwind. The acid rain debate now embraces many western countries - including Canada, the US, England, Scotland, Wales, Sweden, Norway, Denmark, West Germany, the Netherlands, Austria, Switzerland - and a growing number of eastern countries - including the Soviet Union, Poland, East Germany, and Czechoslovakia. The problem of acid rain arises, strictly speaking, not so much from the rainfall itself as from its effects on the environment. Runoff affects surface water and groundwater, as well as soils and vegetation. Consequently changes in rainfall acidity can trigger off a range of impacts on the chemistry and ecology of lakes and rivers, soil chemistry and processes, the health and productivity of plants, and building materials, and metallic structures. The most suitable solutions to the problems of acid rain require prevention rather than cure, and there is broad agreement in both the political scientific communities on the need to reduce emissions of sulfur and nitrogen oxides to the atmosphere. Book divisions discuss: the problem of acid rain, the science of acid rain, the technology of acid rain, and the politics of acid rain, in an effort to evaluate this growing global problem of acid rain.

  2. Increased formation of ursodeoxycholic acid in patients treated with chenodeoxycholic acid.

    PubMed Central

    Salen, G; Tint, G S; Eliav, B; Deering, N; Mosbach, E H

    1974-01-01

    The formation of ursodeoxycholic acid, the 7 beta-hydroxy epimer of chenodeoxycholic acid, was investigated in three subjects with cerebrotendinous xanthomatosis and in four subjects with gallstones. Total biliary bile acid composition was analyzed by gas-liquid chromatography before and after 4 months of treatment with 0.75 g/day of chenodeoxycholic acid. Individual bile acids were identified by mass spectrometry. Before treatment, bile from cerebrotendinous xanthomatosis (CTX) subjects contained cholic acid, 85%; chenodeoxycholic acid, 7%; deoxycholic acid, 3%; allocholic acid, 3%; and unidentified steroids, 2%; while bile from gallstone subjects contained cholic acid, 45%; chenodeoxycholic acid, 43%; deoxycholic acid, 11%, and lithocholic acid, 1%. In all subjects, 4 months of chenodeoxycholic acid therapy increased the proportion of this bile acid to approximately 80% and decreased cholic acid to 3% of the total biliary bile acids, the remaining 17% of bile acids were identified as ursodeoxycholic acid. After the intravenous injection of [3H]chenodeoxycholic acid, the specific activity of biliary ursodeoxycholic acid exceeded the specific activity of chenodeoxycholic acid, and the resulting specific activity decay curves suggested precursor-product relationships. When [3H]7-ketolithocholic acid was administrated to another patient treated with chenodeoxycholic acid, radioactivity was detected in both the ursodeoxycholic acid and chenodeoxycholic acid fractions. These results indicate that substantial amounts of ursodeoxycholic acid are formed in patients treated with chenodeoxycholic acid. The ursodeoxycholic acid was synthesized from chenodeoxycholic acid presumably via 7-ketolithocholic acid. Images PMID:11344576

  3. Interactions of amino acids, carboxylic acids, and mineral acids with different quinoline derivatives

    NASA Astrophysics Data System (ADS)

    Kalita, Dipjyoti; Deka, Himangshu; Samanta, Shyam Sundar; Guchait, Subrata; Baruah, Jubaraj B.

    2011-03-01

    A series of quinoline containing receptors having amide and ester bonds are synthesized and characterised. The relative binding abilities of these receptors with various amino acids, carboxylic acids and mineral acids are determined by monitoring the changes in fluorescence intensity. Among the receptors bis(2-(quinolin-8-yloxy)ethyl) isophthalate shows fluorescence enhancement on addition of amino acids whereas the other receptors shows fluorescence quenching on addition of amino acids. The receptor N-(quinolin-8-yl)-2-(quinolin-8-yloxy) propanamide has higher binding affinity for amino acids. However, the receptor N-(quinolin-8-yl)-2-(quinolin-8-yloxy)acetamide having similar structure do not bind to amino acids. This is attributed to the concave structure of the former which is favoured due to the presence of methyl substituent. The receptor bis(2-(quinolin-8-yloxy)ethyl) isophthalate do not bind to hydroxy carboxylic acids, but is a good receptor for dicarboxylic acids. The crystal structure of bromide and perchlorate salts of receptor 2-bromo-N-(quinolin-8-yl)-propanamide are determined. In both the cases the amide groups are not in the plane of quinoline ring. The structure of N-(quinolin-8-yl)-2-(quinolin-8-yloxy)acetamide, N-(2-methoxyphenethyl)-2-(quinolin-8-yloxy)acetamide and their salts with maleic acid as well as fumaric acid are determined. It is observed that the solid state structures are governed by the double bond geometry of these two acid. Maleic acid forms salt in both the cases, whereas fumaric acid forms either salt or co-crystals.

  4. Acidity of Strong Acids in Water and Dimethyl Sulfoxide.

    PubMed

    Trummal, Aleksander; Lipping, Lauri; Kaljurand, Ivari; Koppel, Ilmar A; Leito, Ivo

    2016-05-26

    Careful analysis and comparison of the available acidity data of HCl, HBr, HI, HClO4, and CF3SO3H in water, dimethyl sulfoxide (DMSO), and gas-phase has been carried out. The data include experimental and computational pKa and gas-phase acidity data from the literature, as well as high-level computations using different approaches (including the W1 theory) carried out in this work. As a result of the analysis, for every acid in every medium, a recommended acidity value is presented. In some cases, the currently accepted pKa values were revised by more than 10 orders of magnitude. PMID:27115918

  5. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as... sulfuric acid or hydrochloric acid as impurities, when offered for transportation or transported by rail... 49 Transportation 2 2014-10-01 2014-10-01 false Nitric acid. 173.158 Section...

  6. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as... sulfuric acid or hydrochloric acid as impurities, when offered for transportation or transported by rail... 49 Transportation 2 2011-10-01 2011-10-01 false Nitric acid. 173.158 Section...

  7. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as... sulfuric acid or hydrochloric acid as impurities, when offered for transportation or transported by rail... 49 Transportation 2 2010-10-01 2010-10-01 false Nitric acid. 173.158 Section...

  8. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as... sulfuric acid or hydrochloric acid as impurities, when offered for transportation or transported by rail... 49 Transportation 2 2013-10-01 2013-10-01 false Nitric acid. 173.158 Section...

  9. Shaping up nucleic acid computation

    PubMed Central

    Chen, Xi

    2010-01-01

    Summary of recent advances (abstract) Nucleic acid-based nanotechnology has always been perceived as novel, but has begun to move from theoretical demonstrations to practical applications. In particular, the large address spaces available to nucleic acids can be exploited to encode algorithms and/or act as circuits, and thereby process molecular information. In this review we revisit several milestones in the field of nucleic acid-based computation, but also highlight how the prospects for nucleic acid computation go beyond just a large address space. Functional nucleic acid elements (aptamers, ribozymes, and deoxyribozymes) can serve as inputs and outputs to the environment, and can act as logical elements. Into the future, the chemical dynamics of nucleic acids may prove as useful as hybridization for computation. PMID:20538451

  10. Clinical use of acid steatocrit.

    PubMed

    Van den Neucker, A; Pestel, N; Tran, T M; Forget, P P; Veeze, H J; Bouquet, J; Sinaasappel, M

    1997-05-01

    Malabsorption of fat is an important gastrointestinal cause of malnutrition and growth retardation in childhood. The gold standard for the evaluation of fat malabsorption is the faecal fat balance method. The acid steatocrit method has recently been introduced as a simple method to evaluate faecal fat. The present study was aimed at evaluating the acid steatocrit in clinical practice. Faecal fat excretion and acid steatocrit results were determined in 42 children, half with and half without fat malabsorption. Acid steatocrit results correlated significantly with both faecal fat excretion (p < 0.01) and faecal fat concentration (p < 0.001). Sensitivity and specificity of the acid steatocrit for the diagnosis of malabsorption were 90% and 100%, respectively. We consider the acid steatocrit method useful for the screening and monitoring of patients with steatorrhoea. PMID:9183483

  11. Acid rain degradation of nylon

    SciTech Connect

    Kyllo, K.E.

    1984-01-01

    Acid rain, precipitation with a pH less than 5.6, is known to damage lakes, vegetation and buildings. Degradation of outdoor textiles by acid rain is strongly suspected but not well documented. This study reports the effects of sunlight, aqueous acid, heat and humidity (acid rain conditions) on spun delustered nylon 6,6 fabric. Untreated nylon and nylon treated with sulfuric acid of pH 2.0, 3.0, and 4.4 were exposed to light in an Atlas Xenon-arc fadeometer at 63/sup 0/C and 65% R.H. for up to 640 AATCC Fading Units. The untreated and acid treated nylon fabrics were also exposed to similar temperature and humidity condition without light. Nylon degradation was determined by changes in breaking strength, elongation, molecular weight, color, amino end group concentration (NH/sub 2/) and /sup 13/C NMR spectra. Physical damage was assessed using SEM.

  12. A Simpler Nucleic Acid

    NASA Technical Reports Server (NTRS)

    Orgel, Leslie

    2000-01-01

    It has been supposed that for a nucleic acid analog to pair with RNA it must, like RNA, have a backbone with at least a sixatom repeat; a shorter backbone presumably would not stretch far enough to bind RNA properly. The Eschenmoser group has shown, however, that this first impression is incorrect.As they report in their new paper, Eschenmoser and co-workers ( I ) have now synthesized a substantial number of these polymers, which are called (L)-a-threofuranosyl oligonucleotides or TNAs. They are composed of bases linked to a threose sugar-phosphate backbone, with phosphodiester bonds connecting the nucleotides. The investigators discovered that pairs of complementary TNAs do indeed form stable Watson-Crick double helices and, perhaps more importantly, that TNAs form stable double helices with complementary RNAs and DNAs.

  13. Ghrelin and gastric acid secretion

    PubMed Central

    Yakabi, Koji; Kawashima, Junichi; Kato, Shingo

    2008-01-01

    Ghrelin, a novel growth hormone-releasing peptide, was originally isolated from rat and human stomach. Ghrelin has been known to increase the secretion of growth hormone (GH), food intake, and body weight gain when administered peripherally or centrally. Ghrelin is also known to stimulate the gastric motility and the secretion of gastric acid. In the previous studies, the action of ghrelin on acid secretion was shown to be as strong as that of histamine and gastrin in in-vivo experiment. In the studies, the mechanism for the action of ghrelin was also investigated. It was shown that vagotomy completely inhibited the action of ghrelin on the secretion of gastric acid suggesting that vagal nerve is involved in the mechanism for the action of ghrelin on acid secretion. As famotidine did not inhibit ghrelin-induced acid secretion in the study by Masuda et al, they concluded that histamine was not involved in the action of ghrelin on acid secretion. However, we have shown that famotidine completely inhibited ghrelin-induced acid secretion and histidine decarboxylase (HDC) mRNA was increased in gastric mucosa by ghrelin injection which is inhibited by vagotomy Our results indicate that histamine is involved in the action of ghrelin on acid secretion. Furthermore synergistic action of gastrin and ghrelin on gastric acid secretion was shown. Although gastrin has important roles in postprandial secretion of gastric acid, ghrelin may be related to acid secretion during fasting period or at night. However, further studies are needed to elucidate the physiological role of ghrelin in acid secretion. PMID:19009648

  14. Organic Acids by Ion Chromatography

    NASA Astrophysics Data System (ADS)

    Rich, William E.; Johnson, Edward; Lois, Louis; Stafford, Brian E.; Kabra, Pokar M.; Marton, Laurence J.

    The presence of increased levels of various organic acids in physiological fluids such as serum, plasma, and urine has been correlated with a variety of diseases (1). Although some are rare, others such as lactic acidosis and hyperoxaluria are more widespread (2, 3). The estimation of organic acids in biological fluids has long been an analytical problem owing to the nature of the samples and the hydrophilic behavior of the various acids.

  15. All-trans retinoic acid regulates hepatic bile acid homeostasis

    PubMed Central

    Yang, Fan; He, Yuqi; Liu, Hui-Xin; Tsuei, Jessica; Jiang, Xiaoyue; Yang, Li; Wang, Zheng-Tao; Wan, Yu-Jui Yvonne

    2014-01-01

    Retinoic acid (RA) and bile acids share common roles in regulating lipid homeostasis and insulin sensitivity. In addition, the receptor for RA (retinoid x receptor) is a permissive partner of the receptor for bile acids, farnesoid x receptor (FXR/NR1H4). Thus, RA can activate the FXR-mediated pathway as well. The current study was designed to understand the effect of all-trans RA on bile acid homeostasis. Mice were fed an all-trans RA-supplemented diet and the expression of 46 genes that participate in regulating bile acid homeostasis was studied. The data showed that all-trans RA has a profound effect in regulating genes involved in synthesis and transport of bile acids. All-trans RA treatment reduced the gene expression levels of Cyp7a1, Cyp8b1, and Akr1d1, which are involved in bile acid synthesis. All-trans RA also decreased the hepatic mRNA levels of Lrh-1 (Nr5a2) and Hnf4α (Nr2a1), which positively regulate the gene expression of Cyp7a1 and Cyp8b1. Moreover, all-trans RA induced the gene expression levels of negative regulators of bile acid synthesis including hepatic Fgfr4, Fxr, and Shp (Nr0b2) as well as ileal Fgf15. All-trans RA also decreased the expression of Abcb11 and Slc51b, which have a role in bile acid transport. Consistently, all-trans RA reduced hepatic bile acid levels and the ratio of CA/CDCA, as demonstrated by liquid chromatography-mass spectrometry. The data suggest that all-trans RA-induced SHP may contribute to the inhibition of CYP7A1 and CYP8B1, which in turn reduces bile acid synthesis and affects lipid absorption in the gastrointestinal tract. PMID:25175738

  16. Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

    NASA Astrophysics Data System (ADS)

    Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

    2016-03-01

    Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

  17. Acidity of frozen electrolyte solutions.

    PubMed

    Robinson, Carmen; Boxe, C S; Guzman, M I; Colussi, A J; Hoffmann, M R

    2006-04-20

    Ice is selectively intolerant to impurities. A preponderance of implanted anions or cations generates electrical imbalances in ice grown from electrolyte solutions. Since the excess charges are ultimately neutralized via interfacial (H(+)/HO(-)) transport, the acidity of the unfrozen portion can change significantly and permanently. This insufficiently recognized phenomenon should critically affect rates and equilibria in frozen media. Here we report the effective (19)F NMR chemical shift of 3-fluorobenzoic acid as in situ probe of the acidity of extensively frozen electrolyte solutions. The sign and magnitude of the acidity changes associated with freezing are largely determined by specific ion combinations, but depend also on solute concentration and/or the extent of supercooling. NaCl solutions become more basic, those of (NH(4))(2)SO(4) or Na(2)SO(4) become more acidic, while solutions of the 2-(N-morpholino)ethanesulfonic acid zwitterion barely change their acidity upon freezing. We discuss how acidity scales based on solid-state NMR measurements could be used to assess the degree of ionization of weak acids and bases in frozen media. PMID:16610849

  18. Acidic gas capture by diamines

    DOEpatents

    Rochelle, Gary; Hilliard, Marcus

    2011-05-10

    Compositions and methods related to the removal of acidic gas. In particular, the present disclosure relates to a composition and method for the removal of acidic gas from a gas mixture using a solvent comprising a diamine (e.g., piperazine) and carbon dioxide. One example of a method may involve a method for removing acidic gas comprising contacting a gas mixture having an acidic gas with a solvent, wherein the solvent comprises piperazine in an amount of from about 4 to about 20 moles/kg of water, and carbon dioxide in an amount of from about 0.3 to about 0.9 moles per mole of piperazine.

  19. MedlinePlus: Folic Acid

    MedlinePlus

    ... and Tests Homocysteine Test (American Association for Clinical Chemistry) Vitamin B12 and Folate Test (American Association for Clinical Chemistry) Related Issues Folic Acid Supplements: Can They Slow ...

  20. Bacterial Decarboxylation of o-Phthalic Acids

    PubMed Central

    Taylor, Barrie F.; Ribbons, Douglas W.

    1983-01-01

    The decarboxylation of phthalic acids was studied with Bacillus sp. strain FO, a marine mixed culture ON-7, and Pseudomonas testosteroni. The mixed culture ON-7, when grown anaerobically on phthalate but incubated aerobically with chloramphenicol, quantitatively converted phthalic acid to benzoic acid. Substituted phthalic acids were also decarboxylated: 4,5-dihydroxyphthalic acid to protocatechuic acid; 4-hydroxyphthalic and 4-chlorophthalic acids to 3-hydroxybenzoic and 3-chlorobenzoic acids, respectively; and 3-fluorophthalic acid to 2-and 3-fluorobenzoic acids. Bacillus sp. strain FO gave similar results except that 4,5-dihydroxyphthalic acid was not metabolized, and both 3- and 4-hydroxybenzoic acids were produced from 4-hydroxyphthalic acid. P. testosteroni decarboxylated 4-hydroxyphthalate (to 3-hydroxybenzoate) and 4,5-dihydroxyphthalate but not phthalic acid and halogenated phthalates. Thus, P. testosteroni and the mixed culture ON-7 possessed 4,5-dihydroxyphthalic acid decarboxylase, previously described in P. testosteroni, that metabolized 4,5-dihydroxyphthalic acid and specifically decarboxylated 4-hydroxyphthalic acid to 3-hydroxybenzoic acid. The mixed culture ON-7 and Bacillus sp. strain FO also possessed a novel decarboxylase that metabolized phthalic acid and halogenated phthalates, but not 4,5-dihydroxyphthalate, and randomly decarboxylated 4-hydroxyphthalic acid. The decarboxylation of phthalic acid is suggested to involve an initial reduction to 1,2-dihydrophthalic acid followed by oxidative decarboxylation to benzoic acid. PMID:16346440

  1. Fatty acid-amino acid conjugates diversification in Lepidopteran caterpillars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid amino acid conjugates (FACs) have been found in Noctuid as well as Sphingid caterpillar oral secretions and especially volicitin [N-(17-hydroxylinolenoyl)-L-Glutamine] and its biochemical precursor, N-linolenoyl-L-glutamine, are known elicitors of induced volatile emissions in corn plants...

  2. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances.

    PubMed

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-01

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

  3. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances

    PubMed Central

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-01

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

  4. A comparison of chromic acid and sulfuric acid anodizing

    NASA Technical Reports Server (NTRS)

    Danford, M. D.

    1992-01-01

    Because of federal and state mandates restricting the use of hexavalent chromium, it was deemed worthwhile to compare the corrosion protection afforded 2219-T87 aluminum alloy by both Type I chromic acid and Type II sulfuric acid anodizing per MIL-A-8625. Corrosion measurements were made on large, flat 2219-T87 aluminum alloy sheet material with an area of 1 cm(exp 2) exposed to a corrosive medium of 3.5-percent sodium chloride at pH 5.5. Both ac electrochemical impedance spectroscopy and the dc polarization resistance techniques were employed. The results clearly indicate that the corrosion protection obtained by Type II sulfuric acid anodizing is superior, and no problems should result by substituting Type II sulfuric acid anodizing for Type I chromic acid anodizing.

  5. Effect of propionic acid on fatty acid oxidation and ureagenesis.

    PubMed

    Glasgow, A M; Chase, H P

    1976-07-01

    Propionic acid significantly inhibited 14CO2 production from [1-14C] palmitate at a concentration of 10 muM in control fibroblasts and 100 muM in methylmalonic fibroblasts. This inhibition was similar to that produced by 4-pentenoic acid. Methylmalonic acid also inhibited 14CO2 production from [1-14C] palmitate, but only at a concentration of 1 mM in control cells and 5 mM in methylmalonic cells. Propionic acid (5 mM) also inhibited ureagenesis in rat liver slices when ammonia was the substrate but not with aspartate and citrulline as substrates. Propionic acid had no direct effect on either carbamyl phosphate synthetase or ornithine transcarbamylase. These findings may explain the fatty degeneration of the liver and the hyperammonemia in propionic and methylmalonic acidemia. PMID:934734

  6. Microbial desulfonation of substituted naphthalenesulfonic acids and benzenesulfonic acids.

    PubMed Central

    Zürrer, D; Cook, A M; Leisinger, T

    1987-01-01

    Sulfur-limited batch enrichment cultures containing one of nine multisubstituted naphthalenesulfonates and an inoculum from sewage yielded several taxa of bacteria which could quantitatively utilize 19 sulfonated aromatic compounds as the sole sulfur source for growth. Growth yields were about 4 kg of protein per mol of sulfur. Specific degradation rates were about 4 to 14 mu kat/kg of protein. A Pseudomonas sp., an Arthrobacter sp., and an unidentified bacterium were examined. Each desulfonated at least 16 aromatic compounds, none of which served as a carbon source. Pseudomonas sp. strain S-313 converted 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 5-amino-1-naphthalenesulfonic acid, benzenesulfonic acid, and 3-aminobenzenesulfonic acid to 1-naphthol, 2-naphthol, 5-amino-1-naphthol, phenol, and 3-aminophenol, respectively. Experiments with 18O2 showed that the hydroxyl group was derived from molecular oxygen. PMID:3662502

  7. Carbonic Acid Retreatment of Biomass

    SciTech Connect

    Baylor university

    2003-06-01

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. (1) Solidify the theoretical understanding of the binary CO{sub 2}/H{sub 2}O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. (2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. (3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. (4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. (5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for

  8. Carbonic Acid Pretreatment of Biomass

    SciTech Connect

    G. Peter van Walsum; Kemantha Jayawardhana; Damon Yourchisin; Robert McWilliams; Vanessa Castleberry

    2003-05-31

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic

  9. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc. PMID:26990649

  10. Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

    PubMed Central

    Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

    1988-01-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

  11. In-silico design of computational nucleic acids for molecular information processing

    PubMed Central

    2013-01-01

    Within recent years nucleic acids have become a focus of interest for prototype implementations of molecular computing concepts. During the same period the importance of ribonucleic acids as components of the regulatory networks within living cells has increasingly been revealed. Molecular computers are attractive due to their ability to function within a biological system; an application area extraneous to the present information technology paradigm. The existence of natural information processing architectures (predominately exemplified by protein) demonstrates that computing based on physical substrates that are radically different from silicon is feasible. Two key principles underlie molecular level information processing in organisms: conformational dynamics of macromolecules and self-assembly of macromolecules. Nucleic acids support both principles, and moreover computational design of these molecules is practicable. This study demonstrates the simplicity with which one can construct a set of nucleic acid computing units using a new computational protocol. With the new protocol, diverse classes of nucleic acids imitating the complete set of boolean logical operators were constructed. These nucleic acid classes display favourable thermodynamic properties and are significantly similar to the approximation of successful candidates implemented in the laboratory. This new protocol would enable the construction of a network of interconnecting nucleic acids (as a circuit) for molecular information processing. PMID:23647621

  12. In-silico design of computational nucleic acids for molecular information processing.

    PubMed

    Ramlan, Effirul Ikhwan; Zauner, Klaus-Peter

    2013-01-01

    Within recent years nucleic acids have become a focus of interest for prototype implementations of molecular computing concepts. During the same period the importance of ribonucleic acids as components of the regulatory networks within living cells has increasingly been revealed. Molecular computers are attractive due to their ability to function within a biological system; an application area extraneous to the present information technology paradigm. The existence of natural information processing architectures (predominately exemplified by protein) demonstrates that computing based on physical substrates that are radically different from silicon is feasible. Two key principles underlie molecular level information processing in organisms: conformational dynamics of macromolecules and self-assembly of macromolecules. Nucleic acids support both principles, and moreover computational design of these molecules is practicable. This study demonstrates the simplicity with which one can construct a set of nucleic acid computing units using a new computational protocol. With the new protocol, diverse classes of nucleic acids imitating the complete set of boolean logical operators were constructed. These nucleic acid classes display favourable thermodynamic properties and are significantly similar to the approximation of successful candidates implemented in the laboratory. This new protocol would enable the construction of a network of interconnecting nucleic acids (as a circuit) for molecular information processing. PMID:23647621

  13. Acid rain: effects on fish and wildlife

    SciTech Connect

    Mayer, K.S.; Multer, E.P.; Schreiber, R.K.

    1984-01-01

    The following questions concerning acid rain are discussed: what is acid rain; what causes acid rain; where do sulfur and nitrogen oxides originate; what areas in the U.S. are susceptible to acid rain; are there early warning signals of acidification to aquatic resources; how does acid rain affect fishery resources; does acid rain affect wildlife; and how can effects of acid rain be reduced.

  14. Synthesis of (+) and (-)-phaselic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    (2S)-Phaselic acid (2S-O-caffeoylmalate) is a common plant metabolite belonging to the o-diphenol subclass of phenolic secondary metabolites. Our interest in this metabolite stems from previous studies showing that the presence of (2S)-phaselic acid in red clover is crucial to the preservation of ut...

  15. Synthesis of (+)- and (-)-phaselic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    (2S)-Phaselic acid (2S-O-caffeoylmalate) is a common plant metabolite belonging to the o-diphenol subclass of phenolic secondary metabolites. Our interest in this metabolite stems from previous studies showing that the presence of (2S)-phaselic acid in red clover is crucial to the preservation of ut...

  16. BOTANICAL ASPECTS OF ACIDIC PRECIPITATION

    EPA Science Inventory

    Acidic precipitation can be characterized as wet or frozen atmospheric deposition with a hydrogen ion concentration greater than 2.5 microequivalents liter-1. Acidic precipitation is perceived as a significant air pollution problem derived chiefly from combustion of fossil fuels,...

  17. SOIL REACTION AND ACIDIC DEPOSITION

    EPA Science Inventory

    This chapter discusses the major chemical processes by which acidic deposition interacts with soils. he focus is on forest soils, as the effects of acidic deposition on soils used for production of food and fiber are generally small compared to effects of agricultural practices s...

  18. Acid Rain: The Scientific Challenge.

    ERIC Educational Resources Information Center

    Godfrey, Paul J.

    1991-01-01

    Documents the workings and findings of the Massachusetts Acid Rain Monitoring Project, which has pooled the volunteer efforts of more than 1,000 amateur and professional scientists since 1983. Reports on the origins of air pollution, the prediction of acid rain, and its effects on both water life and land resources. (JJK)

  19. Acid Rain: An Educational Opportunity?

    ERIC Educational Resources Information Center

    Marion, James I.

    1984-01-01

    Deals with how educators can handle the subject of acid rain; illustrates suggestions with experiences of grade nine students visiting Frost Valley Environmental Education Center (Oliverea, New York) to learn scientific concepts through observation of outdoor phenomena, including a stream; and discusses acid rain, pH levels, and pollution control…

  20. Acid Rain: What's the Forecast?

    ERIC Educational Resources Information Center

    Bybee, Rodger

    1984-01-01

    Discusses various types of acid rain, considered to be a century-old problem. Topics include: wet and dry deposition, effects on a variety of environments, ecosystems subject to detrimental effects, and possible solutions to the problem. A list of recommended resources on acid rain is provided. (BC)

  1. Acid rain & electric utilities II

    SciTech Connect

    1997-12-31

    This document presents reports which were presented at the Acid Rain and Electric Utilities Conference. Topics include environmental issues and electric utilities; acid rain program overview; global climate change and carbon dioxide; emissions data management; compliance; emissions control; allowance and trading; nitrogen oxides; and assessment. Individual reports have been processed separately for the United States Department of Energy databases.

  2. Acid Precipitation: Causes and Consequences.

    ERIC Educational Resources Information Center

    Babich, Harvey; And Others

    1980-01-01

    This article is the first of three articles in a series on the acid rain problem in recent years. Discussed are the causes of acid precipitation and its consequences for the abiotic and biotic components of the terrestrial and aquatic ecosystems, and for man-made materials. (Author/SA)

  3. TRANS ACIDS IN SPECIALTY LIPIDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The role of trans acids in human health and nutrition is highly controversial and a search of the Internet reveals the interest in the subject. Trans acids are perceived as "killer fats" at one end of the spectrum to having no adverse effects at the other. In addition, saturated fats are perceived...

  4. Acid precipitation in historical perspective

    SciTech Connect

    Cowling, E.B.

    1982-02-01

    The history of acid precipitation is traced from the first awareness of the problem in the mid-17th century to the present. An outline of the National Acid Precipitation Assessment program is also given, and the author makes recommendations for future research. (JMT)

  5. SIMULATED ACID RAIN ON CROPS

    EPA Science Inventory

    In 1981, simulated H2SO4 acid rain was applied to alfalfa and tall fescue and a 2:1 ratio of H2SO4:HNO3 acid rain was applied to alfalfa, tall fescue, barley, wheat, potato, tomato, radish, and corn crops growing in the open field at Corvallis, Oregon. Careful attention was given...

  6. Acid rain: a background report

    SciTech Connect

    Glustrom, L.; Stolzenberg, J.

    1982-07-08

    This Staff Brief was prepared for the Wisconsin Legislative Council's Special Committee on Acid Rain to provide an introduction to the issue of acid rain. It is divided into four parts. Part I provides an overview on the controversies surrounding the measurement, formation and effects of acid rain. As described in Part I, the term acid rain is used to describe the deposition of acidic components through both wet deposition (e.g., rain or snow) and dry deposition (e.g., direct contact between atmospheric constituents and the land, water or vegetation of the earth). Part II presents background information on state agency activities relating to acid rain in Wisconsin, describes what is known about the occurrence of, susceptibility to and effects of acid rain in Wisconsin, and provides information related to man-made sources of sulfur and nitrogen oxides in Wisconsin. Part III describes major policies and regulations relating to acid rain which have been or are being developed jointly by the United States and Canadian governments, by the United States government and by the State of Wisconsin. Part IV briefly discusses possible areas for Committee action.

  7. Getting Back to Basics (& Acidics)

    ERIC Educational Resources Information Center

    Rhodes, Sam

    2006-01-01

    This article describes a few novel acid-base experiments intended to introduce students to the basic concepts of acid-base chemistry and provide practical examples that apply directly to the study of biology and the human body. Important concepts such as the reaction between carbon dioxide and water, buffers and protein denaturation, are covered.…

  8. ACID DEPOSITION AND FOREST DECLINE

    EPA Science Inventory

    The location, topography and other characteristics of the high-elevation forests of eastern North America cause them to be receptors of high levels of acid deposition and airborn trace metals. No other major forested areas in the U.S. are subjected to such intensely acid cloud mo...

  9. Acid Tests and Basic Fun.

    ERIC Educational Resources Information Center

    McBride, John W.

    1995-01-01

    Explores acids and bases using different indicators, such as turmeric, purple grape juice, and lichens. Because some of these indicators are not as sensitive as cabbage juice or litmus paper, determining to which acids and bases each indicator is sensitive presents an enjoyable, problem-solving challenge for students. Presents directions for…

  10. Synthesis of pyromellitic acid esters

    NASA Technical Reports Server (NTRS)

    Fedorova, V. A.; Donchak, V. A.; Martynyuk-Lototskaya, A. N.

    1985-01-01

    The ester acids necessary for studyng the thermochemical properties of pyromellitic acid (PMK)-based peroxides were investigated. Obtaining a tetramethyl ester of a PMK was described. The mechanism of an esterification reaction is discussed, as is the complete esterification of PMK with primary alcohol.

  11. Lead-acid battery

    SciTech Connect

    Rowlette, J.J.

    1983-09-20

    A light weight lead-acid battery is disclosed having a positive terminal and a negative terminal and including one or more cells or grid stacks having a plurality of vertically stacked conductive monoplates with positive active material and negative active material deposited on alternating plates in the cell or grid stack. Electrolyte layers positioned between each monoplate are included to provide a battery cell having four sides which is capable of being electrically charged and discharged. Two vertical positive bus bars are provided on opposite sides of the battery cell for connecting the monoplates with positive active material together in parallel current conducting relation. In addition, two negative bus bars on opposite sides of the battery cell each being adjacent the positive bus bars are provided for connecting the monoplates with negative active material together in parallel current conducting relation. The positive and negative bus bars not only provide a low resistance method for connecting the plurality of conductive monoplates of their respective battery terminals but also provides support and structural strength to the battery cell structure. In addition, horizontal orientation of monoplates is provided in a vertical stacking arrangement to reduce electrolyte stratification and short circuiting due to flaking of positive and negative active materials from the monoplates.

  12. Lead-acid battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1983-01-01

    A light weight lead-acid battery (30) having a positive terminal (36) and a negative terminal (34) and including one or more cells or grid stacks having a plurality of vertically stacked conductive monoplates (10, 20) with positive active material and negative active material deposited on alternating plates in the cell or grid stack. Electrolyte layers (26, 28) positioned between each monoplate are included to provide a battery cell having four sides which is capable of being electrically charged and discharged. Two vertical positive bus bars (42, 43) are provided on opposite sides of the battery cell for connecting the monoplates (10) with positive active material together in parallel current conducting relation. In addition, two negative bus bars (38, 39) on opposite sides of the battery cell each being adjacent the positive bus bars are provided for connecting the monoplates (20) with negative active material together in parallel current conducting relation. The positive (42, 43) and negative (38, 39) bus bars not only provide a low resistance method for connecting the plurality of conductive monoplates of their respective battery terminals (36, 34) but also provides support and structural strength to the battery cell structure. In addition, horizontal orientation of monoplates (10, 20) is provided in a vertical stacking arrangement to reduce electrolyte stratification and short circuiting due to flaking of positive and negative active materials from the monoplates.

  13. Atmospheric dust and acid rain

    SciTech Connect

    Hedin, L.O.; Likens, G.E.

    1996-12-01

    Why is acid rain still an environmental problem in Europe and North America despite antipollution reforms? The answer really is blowing in the wind: atmospheric dust. These airborne particles can help neutralize the acids falling on forests, but dust levels are unusually low these days. In the air dust particles can neutralize acid rain. What can we do about acid rain and atmospheric dust? Suggestions range from the improbable to the feasible. One reasonable suggestion is to reduce emissions of acidic pollutants to levels that can be buffered by natural quantities of basic compounds in the atmosphere; such a goal would mean continued reductions in sulfur dioxide and nitrogen oxides, perhaps even greater than those prescribed in the 1990 Amendments to the Clean Air Act in the U.S. 5 figs.

  14. Microfluidics in amino acid analysis.

    PubMed

    Pumera, Martin

    2007-07-01

    Microfluidic devices have been widely used to derivatize, separate, and detect amino acids employing many different strategies. Virtually zero-dead volume interconnections and fast mass transfer in small volume microchannels enable dramatic increases in on-chip derivatization reaction speed, while only minute amounts of sample and reagent are needed. Due to short channel path, fast subsecond separations can be carried out. With sophisticated miniaturized detectors, the whole analytical process can be integrated on one platform. This article reviews developments of lab-on-chip technology in amino acid analysis, it shows important design features such as sample preconcentration, precolumn and postcolumn amino acid derivatization, and unlabeled and labeled amino acid detection with focus on advanced designs. The review also describes important biomedical and space exploration applications of amino acid analysis on microfluidic devices. PMID:17542043

  15. Synthesis of higher monocarboxylic acids

    SciTech Connect

    Taikov, B.F.; Novakovskii, E.M.; Zhelkovskaya, V.P.; Shadrova, V.N.; Shcherbik, P.K.

    1981-01-01

    Brown-coal and peat waxes contain higher monocarboxylic acids, alcohols and esters of them as their main components. In view of this, considerable interest is presented by the preparation of individual compounds among those mentioned above, which is particularly important in the study of the composition and development of the optimum variants of the chemical processing of the waxes. In laboratory practice, to obtain higher monocarboxylic acids use is generally made of electrosynthesis according to Kolbe which permits unbranched higher aliphatic acids with given lengths of the hydrocarbon chain to be obtained. The aim of the present work was to synthesize higher monocarboxylic acids: arachidic, behenic, lignoceric, pentacosanoic, erotic, heptacosanoic, montanic, nonacosanoic, melissic, dotriacontanoic and tetratriacontanoic, which are present in waxes. Characteristics of synthesized acids are tabulated. 20 refs.

  16. Fumaric acid production by fermentation

    PubMed Central

    Roa Engel, Carol A.; Zijlmans, Tiemen W.; van Gulik, Walter M.; van der Wielen, Luuk A. M.

    2008-01-01

    The potential of fumaric acid as a raw material in the polymer industry and the increment of cost of petroleum-based fumaric acid raises interest in fermentation processes for production of this compound from renewable resources. Although the chemical process yields 112% w/w fumaric acid from maleic anhydride and the fermentation process yields only 85% w/w from glucose, the latter raw material is three times cheaper. Besides, the fermentation fixes CO2. Production of fumaric acid by Rhizopus species and the involved metabolic pathways are reviewed. Submerged fermentation systems coupled with product recovery techniques seem to have achieved economically attractive yields and productivities. Future prospects for improvement of fumaric acid production include metabolic engineering approaches to achieve low pH fermentations. PMID:18214471

  17. Sialic acids and autoimmune disease.

    PubMed

    Mahajan, Vinay S; Pillai, Shiv

    2016-01-01

    An important underlying mechanism that contributes to autoimmunity is the loss of inhibitory signaling in the immune system. Sialic acid-recognizing Ig superfamily lectins or Siglecs are a family of cell surface proteins largely expressed in hematopoietic cells. The majority of Siglecs are inhibitory receptors expressed in immune cells that bind to sialic acid-containing ligands and recruit SH2-domain-containing tyrosine phosphatases to their cytoplasmic tails. They deliver inhibitory signals that can contribute to the constraining of immune cells, and thus protect the host from autoimmunity. The inhibitory functions of CD22/Siglec-2 and Siglec-G and their contributions to tolerance and autoimmunity, primarily in the B lymphocyte context, are considered in some detail in this review. The relevance to autoimmunity and unregulated inflammation of modified sialic acids, enzymes that modify sialic acid, and other sialic acid-binding proteins are also reviewed. PMID:26683151

  18. Nucleic acid based molecular devices.

    PubMed

    Krishnan, Yamuna; Simmel, Friedrich C

    2011-03-28

    In biology, nucleic acids are carriers of molecular information: DNA's base sequence stores and imparts genetic instructions, while RNA's sequence plays the role of a messenger and a regulator of gene expression. As biopolymers, nucleic acids also have exciting physicochemical properties, which can be rationally influenced by the base sequence in myriad ways. Consequently, in recent years nucleic acids have also become important building blocks for bottom-up nanotechnology: as molecules for the self-assembly of molecular nanostructures and also as a material for building machinelike nanodevices. In this Review we will cover the most important developments in this growing field of nucleic acid nanodevices. We also provide an overview of the biochemical and biophysical background of this field and the major "historical" influences that shaped its development. Particular emphasis is laid on DNA molecular motors, molecular robotics, molecular information processing, and applications of nucleic acid nanodevices in biology. PMID:21432950

  19. Fluorometric Determination of Deoxyribonucleic Acid in Bacteria with Ethidium Bromide

    PubMed Central

    Donkersloot, J. A.; Robrish, S. A.; Krichevsky, M. I.

    1972-01-01

    A simple, sensitive, and rapid method is presented for the determination of deoxyribonucleic acid (DNA) in both gram-positive and gram-negative bacteria. It is based upon the fluorometric determination of DNA with ethidium bromide after alkaline digestion of the bacteria to hydrolyze the interfering ribonucleic acid. The assay takes less than 2 hr. Its sensitivity is at least 0.2 μg of DNA in a final solution of 4 ml and it uses commonly available filter or double monochromator fluorometers. Judicious choice of light source and filters allows an additional 10-fold increase in sensitivity with a filter fluorometer. Turbidity caused by bacteria or insoluble polysaccharides does not interfere with the fluorescence measurements. There was no significant difference between the results obtained with this method and those obtained with the indole and diphenylamine methods when these assays were applied to Escherichia coli and sucrose- or glucose-grown Streptococcus mutans. The method was also tested by determining the specific growth rate of E. coli. This new procedure should be especially useful for the determination of bacterial DNA in dilute suspensions and for the estimation of bacterial growth or DNA replication where more conventional methods are not applicable or sensitive enough. PMID:4561101

  20. Molten fatty acid based microemulsions.

    PubMed

    Noirjean, Cecile; Testard, Fabienne; Dejugnat, Christophe; Jestin, Jacques; Carriere, David

    2016-06-21

    We show that ternary mixtures of water (polar phase), myristic acid (MA, apolar phase) and cetyltrimethylammonium bromide (CTAB, cationic surfactant) studied above the melting point of myristic acid allow the preparation of microemulsions without adding a salt or a co-surfactant. The combination of SANS, SAXS/WAXS, DSC, and phase diagram determination allows a complete characterization of the structures and interactions between components in the molten fatty acid based microemulsions. For the different structures characterized (microemulsion, lamellar or hexagonal phases), a similar thermal behaviour is observed for all ternary MA/CTAB/water monophasic samples and for binary MA/CTAB mixtures without water: crystalline myristic acid melts at 52 °C, and a thermal transition at 70 °C is assigned to the breaking of hydrogen bounds inside the mixed myristic acid/CTAB complex (being the surfactant film in the ternary system). Water determines the film curvature, hence the structures observed at high temperature, but does not influence the thermal behaviour of the ternary system. Myristic acid is partitioned in two "species" that behave independently: pure myristic acid and myristic acid associated with CTAB to form an equimolar complex that plays the role of the surfactant film. We therefore show that myristic acid plays the role of a solvent (oil) and a co-surfactant allowing the fine tuning of the structure of oil and water mixtures. This solvosurfactant behaviour of long chain fatty acid opens the way for new formulations with a complex structure without the addition of any extra compound. PMID:27241163

  1. Acid soil and acid rain, 2nd edition

    SciTech Connect

    Kennedy, I.R.

    1992-01-01

    This book examines the basic chemical processes involved in acidification in order to better assess their long-term effects on the status of soils, the health of plants and other living species that depend on them. It also discusses acidity, pH and protons their significance in bioenergetics and the consequent role of autotrophic organisms in acidifying ecosystems. This edition incorporates and integrates recent findings that render more explanations of the causes of the environmental impacts of acidity, especially in forests and lakes. Also explores current research into acid rain and soil in order to devise appropriate measures for their amelioration.

  2. Functional nucleic acid probes and uses thereof

    DOEpatents

    Nilsen-Hamilton, Marit

    2006-10-03

    The present invention provides functional nucleic acid probes, and methods of using functional nucleic acid probes, for binding a target to carry out a desired function. The probes have at least one functional nucleic acid, at least one regulating nucleic acid, and at least one attenuator. The functional nucleic acid is maintained in an inactive state by the attenuator and activated by the regulating nucleic acid only in the presence of a regulating nucleic acid target. In its activated state the functional nucleic acid can bind to its target to carry out a desired function, such as generating a signal, cleaving a nucleic acid, or catalyzing a reaction.

  3. Polyglycolic acid induced inflammation

    PubMed Central

    Ceonzo, Kathleen; Gaynor, Anne; Shaffer, Lisa; Kojima, Koji; Vacanti, Charles A.; Stahl, Gregory L.

    2005-01-01

    Tissue and organ replacement have quickly outpaced available supply. Tissue bioengineering holds the promise for additional tissue availability. Various scaffolds are currently used, whereas polyglycolic acid (PGA), which is currently used in absorbable sutures and orthopedic pins, provides an excellent support for tissue development. Unfortunately, PGA can induce a local inflammatory response following implantation, so we investigated the molecular mechanism of inflammation in vitro and in vivo. Degraded PGA induced an acute peritonitis, characterized by neutrophil (PMN) infiltration following intraperitoneal injection in mice. Similar observations were observed using the metabolite of PGA, glycolide. Dissolved PGA or glycolide, but not native PGA, activated the classical complement pathway in human sera, as determined by classical complement pathway hemolytic assays, C3a and C5a production, C3 and immunoglobulin deposition. To investigate whether these in vitro observations translated to in vivo findings, we used genetically engineered mice. Intraperitoneal administration of glycolide or dissolved PGA in mice deficient in C1q, factor D, C1q and factor D or C2 and factor B demonstrated significantly reduced PMN infiltration compared to congenic controls (WT). Mice deficient in C6 also demonstrated acute peritonitis. However, treatment of WT or C6 deficient mice with a monoclonal antibody against C5 prevented the inflammatory response. These data suggest that the hydrolysis of PGA to glycolide activates the classical complement pathway. Further, complement is amplified via the alternative pathway and inflammation is induced by C5a generation. Inhibition of C5a may provide a potential therapeutic approach to limit the inflammation associated with PGA derived materials following implantation. PMID:16548688

  4. 21 CFR 189.155 - Monochloroacetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Monochloroacetic acid. 189.155 Section 189.155... Human Food § 189.155 Monochloroacetic acid. (a) Monochloroacetic acid is the chemical chloroacetic acid... in alcoholic and nonalcoholic beverages. Monochloroacetic acid is permitted in food package...

  5. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  6. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and....1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid occurs naturally are...

  7. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  8. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  9. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  10. Cycloadditions for Studying Nucleic Acids.

    PubMed

    Kath-Schorr, Stephanie

    2016-02-01

    Cycloaddition reactions for site-specific or global modification of nucleic acids have enabled the preparation of a plethora of previously inaccessible DNA and RNA constructs for structural and functional studies on naturally occurring nucleic acids, the assembly of nucleic acid nanostructures, therapeutic applications, and recently, the development of novel aptamers. In this chapter, recent progress in nucleic acid functionalization via a range of different cycloaddition (click) chemistries is presented. At first, cycloaddition/click chemistries already used for modifying nucleic acids are summarized, ranging from the well-established copper(I)-catalyzed alkyne-azide cycloaddition reaction to copper free methods, such as the strain-promoted azide-alkyne cycloaddition, tetrazole-based photoclick chemistry and the inverse electron demand Diels-Alder cycloaddition reaction between strained alkenes and tetrazine derivatives. The subsequent sections contain selected applications of nucleic acid functionalization via click chemistry; in particular, site-specific enzymatic labeling in vitro, either via DNA and RNA recognizing enzymes or by introducing unnatural base pairs modified for click reactions. Further sections report recent progress in metabolic labeling and fluorescent detection of DNA and RNA synthesis in vivo, click nucleic acid ligation, click chemistry in nanostructure assembly and click-SELEX as a novel method for the selection of aptamers. PMID:27572987

  11. Phytic acid in green leaves.

    PubMed

    Hadi Alkarawi, H; Zotz, G

    2014-07-01

    Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention. PMID:24341824

  12. Diabetes and Alpha Lipoic Acid

    PubMed Central

    Golbidi, Saeid; Badran, Mohammad; Laher, Ismail

    2011-01-01

    Diabetes mellitus is a multi-faceted metabolic disorder where there is increased oxidative stress that contributes to the pathogenesis of this debilitating disease. This has prompted several investigations into the use of antioxidants as a complementary therapeutic approach. Alpha lipoic acid, a naturally occurring dithiol compound which plays an essential role in mitochondrial bioenergetic reactions, has gained considerable attention as an antioxidant for use in managing diabetic complications. Lipoic acid quenches reactive oxygen species, chelates metal ions, and reduces the oxidized forms of other antioxidants such as vitamin C, vitamin E, and glutathione. It also boosts antioxidant defense system through Nrf-2-mediated antioxidant gene expression and by modulation of peroxisome proliferator activated receptors-regulated genes. ALA inhibits nuclear factor kappa B and activates AMPK in skeletal muscles, which in turn have a plethora of metabolic consequences. These diverse actions suggest that lipoic acid acts by multiple mechanisms, many of which have only been uncovered recently. In this review we briefly summarize the known biochemical properties of lipoic acid and then discussed the oxidative mechanisms implicated in diabetic complications and the mechanisms by which lipoic acid may ameliorate these reactions. The findings of some of the clinical trials in which lipoic acid administration has been tested in diabetic patients during the last 10 years are summarized. It appears that the clearest benefit of lipoic acid supplementation is in patients with diabetic neuropathy. PMID:22125537

  13. Terahertz spectrum of gallic acid

    NASA Astrophysics Data System (ADS)

    Wu, Meng; Zhao, Guozhong; Wang, Haiyan; Liang, Chengshen

    2009-11-01

    Gallic acid is natural polyphenol compound found in many green plants. More and more experiments have demonstrated that the gallic acid has comprehensive applications. In the field of medicine, the gallic acid plays an important role in antianaphylaxis, antineoplastic, antimycotic, anti-inflammatory, antivirotic, antiasthmatic and inhibiting the degradation of insulin. It also has a lot of applications in chemical industry, food industry and light industry. So it is important to study the terahertz time-domain spectroscopy of gallic acid. Terahertz time-domain spectroscopy (THz-TDS) is a new coherent spectral technology based on the femtosecond laser. In this work, the spectral characteristics of gallic acid in the range of 0.4 THz to 2.6 THz have been measured by THz-TDS. We obtained its absorption and refraction spectra at room temperature. The vibration absorption spectrum of the single molecule between 0.4 THz and 2.6 THz is simulated based on the Density Functional Theory (DFT). It is found that the gallic acid has the spectral response to THz wave in this frequency range. The results show the abnormal dispersion at 1.51 THz and 2.05 THz. These results can be used in the qualitative analysis of gallic acid and the medicine and food inspection.

  14. Pyroligneous acid-the smoky acidic liquid from plant biomass.

    PubMed

    Mathew, Sindhu; Zakaria, Zainul Akmar

    2015-01-01

    Pyroligneous acid (PA) is a complex highly oxygenated aqueous liquid fraction obtained by the condensation of pyrolysis vapors, which result from the thermochemical breakdown or pyrolysis of plant biomass components such as cellulose, hemicellulose, and lignin. PA produced by the slow pyrolysis of plant biomass is a yellowish brown or dark brown liquid with acidic pH and usually comprises a complex mixture of guaiacols, catechols, syringols, phenols, vanillins, furans, pyrans, carboxaldehydes, hydroxyketones, sugars, alkyl aryl ethers, nitrogenated derivatives, alcohols, acetic acid, and other carboxylic acids. The phenolic components, namely guaiacol, alkyl guaiacols, syringol, and alkyl syringols, contribute to the smoky odor of PA. PA finds application in diverse areas, as antioxidant, antimicrobial, antiinflammatory, plant growth stimulator, coagulant for natural rubber, and termiticidal and pesticidal agent; is a source for valuable chemicals; and imparts a smoky flavor for food. PMID:25467926

  15. Drilling fluids containing amps, acrylic acid, itaconic acid polymer

    SciTech Connect

    Bardoliwalla, D.F.

    1987-10-13

    This patent describes an aqueous drilling fluid having present in an amount sufficient to reduce fluid loss of the drilling fluid, at least one polymer of (1) from about 5% to about 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid and (2) from about 95% to about 50% by weight of a second component, there being from 100% to about 80% by weight of acrylic acid and from 0% by weight to about 20% by weight of itaconic acid in the second component. The polymer has a weight average molecular weight of between about 50,000 to about 1,000,000 being in its free acid or partially or completely neutralized form and being at least water dispersible. A method is described of drilling a well into a subterranean formation in which an aqueous drilling fluid is circulated into the well. The step of circulating the drilling fluid contains in an amount sufficient to reduce fluid loss of the drilling fluid, at least one polymer of (1) from about 5% to about 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid and (2) from about 95% to about 50% by weight of a second component. There is from 100% to about 80% by weight of acrylic acid and from 0% by weight to about 20% by weight of itaconic acid in the second component. The polymer has weight average molecular weight of between about 50,000 to about 1,000,000 in its free acid or partially or completely neutralized form and is at least water dispersible.

  16. PRODUCTION OF TRIFLUOROACETIC ACID COMPOUNDS

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-08-30

    A process is described for the preparation of trifluoroacetic acid. Acetone vapor diluted wlth nitrogen and fluorine also diluted with nltrogen are fed separately at a temperature of about 210 deg C into a reaction vessel containing a catalyst mass selected from-the group consisting of silver and gold. The temperature in the reaction vessel is maintained in the range of 200 deg to 250 deg C. The reaction product, trifluoroacetyl fluoride, is absorbed in aqueous alkali solution. Trifluoroacetic acid is recovered from the solution by acidification wlth an acid such as sulfuric followed by steam distillation.

  17. Chemiluminescent measurement of atmospheric acid

    NASA Technical Reports Server (NTRS)

    Stedman, D. H.; Kok, G. L.

    1974-01-01

    The design and construction of a gas phase acid sensitive analyzer are reported. These studies showed that the chemical system was a practical analytical method. A complete instrument was developed and prepared for field testing. A Titan 3-C rocket was scheduled for launching on February 11, 1974. Through preparations made by NASA Langley the instrument was set up to monitor the acid concentration in the rocket exhaust. Due to adverse wind conditions no acid was detected. This entire trip is described in detail.

  18. PHARMACOLOGICAL ACTIVITIES OF PROTOCATECHUIC ACID.

    PubMed

    Khan, Abida Kalsoom; Rashid, Rehana; Fatima, Nighat; Mahmood, Sadaf; Mir, Sadullah; Khan, Sara; Jabeen, Nyla; Murtaza, Ghulam

    2015-01-01

    Protocatechuic acid (3,4-dihydroxybenzoic acid, PCA) is a simple phenolic acid. It is found in a large variety of edible plants and possesses various pharmacological activities. This article aims to review the modern trends in phytochemical isolation and extraction of PCA from plants and other natural resources. Moreover, this article also encompasses pharmacological and biological activities of PCA. It is well known to have anti-inflammatory, antioxidant, anti-hyperglycemia, antibacterial, anticancer, anti-ageing, anti-athro- genic, anti-tumoral, anti-asthma, antiulcer, antispasmodic and neurological properties. PMID:26647619

  19. Can crops tolerate acid rain

    SciTech Connect

    Kaplan, J.K.

    1989-11-01

    This brief article describes work by scientists at the ARS Air Quality-Plant Growth and Development Laboratory in Raleigh, North Carolina, that indicates little damage to crops as a result of acid rain. In studies with simulated acid rain and 216 exposed varieties of 18 crops, there were no significant injuries nor was there reduced growth in most species. Results of chronic and acute exposures were correlated in sensitive tomato and soybean plants and in tolerant winter wheat and lettuce plants. These results suggest that 1-hour exposures could be used in the future to screen varieties for sensitivity to acid rain.

  20. Amino Acids from a Comet

    NASA Technical Reports Server (NTRS)

    Cook, Jamie Elisla

    2009-01-01

    NASA's Stardust spacecraft returned samples from comet 81P/Wild 2 to Earth in January 2006. Examinations of the organic compounds in cometary samples can reveal information about the prebiotic organic inventory present on the early Earth and within the early Solar System, which may have contributed to the origin of life. Preliminary studies of Stardust material revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds (cometary- vs. terrestrial contamination) could not be identified. We have recently measured the carbon isotopic ratios of these amino acids to determine their origin, leading to the first detection of a coetary amino acid.

  1. Be an acid rain detective

    SciTech Connect

    Atwill, L.

    1982-07-01

    Acid rain is discussed in a question and answer format. The article is aimed at educating sport fishermen on the subject, and also to encourage them to write their congressmen, senators, and the President about the acid rain problem. The article also announces the availability of an acid rain test kit available through the magazine, ''Sports Afield.'' The kit consists of pH-test paper that turns different shades of pink and blue according to the pH of the water tested. The color of the test paper is then compared to a color chart furnished in the kit and an approximate pH can be determined.

  2. Abscission: Role of Abscisic Acid

    PubMed Central

    Cracker, L. E.; Abeles, F. B.

    1969-01-01

    The effect of abscisic acid on cotton (Gossypium hirsutum L. cv. Acala 4-42) and bean (Phaseolus vulgaris L. cv. Red Kidney) explants was 2-fold. It increased ethylene production from the explants, which was found to account for some of its ability to accelerate abscission. Absci is acid also increased the activity of cellulase. Increased synthesis of cellulase was not du to an increase in aging of the explants but rather was an effect of abscisic acid on the processes that lead to cellulase synthesis or activity. PMID:16657181

  3. Treatment of Amino Acid Metabolism Disorders

    MedlinePlus

    ... Treatment of amino acid metabolism disorders Treatment of amino acid metabolism disorders E-mail to a friend Please ... this page It's been added to your dashboard . Amino acid metabolism disorders are rare health conditions that affect ...

  4. Genetics Home Reference: sialic acid storage disease

    MedlinePlus

    ... Home Health Conditions sialic acid storage disease sialic acid storage disease Enable Javascript to view the expand/ ... Download PDF Open All Close All Description Sialic acid storage disease is an inherited disorder that primarily ...

  5. Treatment of Fatty Acid Oxidation Disorders

    MedlinePlus

    ... of fatty acid oxidation disorders Treatment of fatty acid oxidation disorders E-mail to a friend Please ... page It's been added to your dashboard . Fatty acid oxidation disorders are rare health conditions that affect ...

  6. Molar extinction coefficients of some fatty acids

    NASA Astrophysics Data System (ADS)

    Sandhu, G. K.; Singh, Kulwant; Lark, B. S.; Gerward, L.

    2002-10-01

    The attenuation of gamma rays in some fatty acids, viz. formic acid (CH 2O 2), acetic acid (C 2H 4O 2), propionic acid (C 3H 6O 2), butyric acid (C 4H 8O 2), n-hexanoic acid (C 6H 12O 2), n-caprylic acid (C 8H 16O 2), lauric acid (C 12H 24O 2), myristic acid (C 14H 28O 2), palmitic acid (C 16H 32O 2), oleic acid (C 18H 34O 2) and stearic acid (C 18H 36O 2), has been measured at the photon energies 81, 356, 511, 662, 1173 and 1332 keV. Experimental values for the molar extinction coefficient, the effective atomic number and the electron density have been derived and compared with theoretical calculations. There is good agreement between experiment and theory.

  7. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E. Philip; Alexandratos, Spiro D.; Gatrone, Ralph C.; Chiarizia, Ronato

    1995-01-01

    An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

  8. Microbial production of lactic acid.

    PubMed

    Eiteman, Mark A; Ramalingam, Subramanian

    2015-05-01

    Lactic acid is an important commodity chemical having a wide range of applications. Microbial production effectively competes with chemical synthesis methods because biochemical synthesis permits the generation of either one of the two enantiomers with high optical purity at high yield and titer, a result which is particularly beneficial for the production of poly(lactic acid) polymers having specific properties. The commercial viability of microbial lactic acid production relies on utilization of inexpensive carbon substrates derived from agricultural or waste resources. Therefore, optimal lactic acid formation requires an understanding and engineering of both the competing pathways involved in carbohydrate metabolism, as well as pathways leading to potential by-products which both affect product yield. Recent research leverages those biochemical pathways, while researchers also continue to seek strains with improved tolerance and ability to perform under desirable industrial conditions, for example, of pH and temperature. PMID:25604523

  9. Low acid producing solid propellants

    NASA Technical Reports Server (NTRS)

    Bennett, Robert R.

    1995-01-01

    The potential environmental effects of the exhaust products of conventional rocket propellants have been assessed by various groups. Areas of concern have included stratospheric ozone, acid rain, toxicity, air quality and global warming. Some of the studies which have been performed on this subject have concluded that while the impacts of rocket use are extremely small, there are propellant development options which have the potential to reduce those impacts even further. This paper discusses the various solid propellant options which have been proposed as being more environmentally benign than current systems by reducing HCI emissions. These options include acid neutralized, acid scavenged, and nonchlorine propellants. An assessment of the acid reducing potential and the viability of each of these options is made, based on current information. Such an assessment is needed in order to judge whether the potential improvements justify the expenditures of developing the new propellant systems.

  10. Abiotic synthesis of fatty acids

    NASA Technical Reports Server (NTRS)

    Leach, W. W.; Nooner, D. W.; Oro, J.

    1978-01-01

    The formation of fatty acids by Fischer-Tropsch-type synthesis was investigated with ferric oxide, ammonium carbonate, potassium carbonate, powdered Pueblito de Allende carbonaceous chondrite, and filings from the Canyon Diablo meteorite used as catalysts. Products were separated and identified by gas chromatography and mass spectrometry. Iron oxide, Pueblito de Allende chondrite, and Canyon Diablo filings in an oxidized catalyst form yielded no fatty acids. Canyon Diablo filings heated overnight at 500 C while undergoing slow purging by deuterium produced fatty acids only when potassium carbonate was admixed; potassium carbonate alone also produced these compounds. The active catalytic combinations gave relatively high yields of aliphatic and aromatic hydrocarbons; substantial amounts of n-alkenes were almost invariably observed when fatty acids were produced; the latter were in the range C6 to C18, with maximum yield in C9 or 10.

  11. Bile acid sequestrants for cholesterol

    MedlinePlus

    ... ency/patientinstructions/000787.htm Bile acid sequestrants for cholesterol To use the sharing features on this page, ... are medicines that help lower your LDL (bad) cholesterol . Too much cholesterol in your blood can stick ...

  12. Biopreservation by lactic acid bacteria.

    PubMed

    Stiles, M E

    1996-10-01

    Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Lactic acid bacteria have a major potential for use in biopreservation because they are safe to consume and during storage they naturally dominate the microflora of many foods. In milk, brined vegetables, many cereal products and meats with added carbohydrate, the growth of lactic acid bacteria produces a new food product. In raw meats and fish that are chill stored under vacuum or in an environment with elevated carbon dioxide concentration, the lactic acid bacteria become the dominant population and preserve the meat with a "hidden' fermentation. The same applies to processed meats provided that the lactic acid bacteria survive the heat treatment or they are inoculated onto the product after heat treatment. This paper reviews the current status and potential for controlled biopreservation of foods. PMID:8879414

  13. Antibiofilm Properties of Acetic Acid

    PubMed Central

    Bjarnsholt, Thomas; Alhede, Morten; Jensen, Peter Østrup; Nielsen, Anne K.; Johansen, Helle Krogh; Homøe, Preben; Høiby, Niels; Givskov, Michael; Kirketerp-Møller, Klaus

    2015-01-01

    Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These biofilms cause the persistence of chronic infections. Since antibiotics rarely resolve these infections, the only effective treatment of chronic infections is surgical removal of the infected implant, tissue, or organ and thereby the biofilm. Acetic acid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram-negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms. PMID:26155378

  14. Biotechnological production of citric acid

    PubMed Central

    Max, Belén; Salgado, José Manuel; Rodríguez, Noelia; Cortés, Sandra; Converti, Attilio; Domínguez, José Manuel

    2010-01-01

    This work provides a review about the biotechnological production of citric acid starting from the physicochemical properties and industrial applications, mainly in the food and pharmaceutical sectors. Several factors affecting citric acid fermentation are discussed, including carbon source, nitrogen and phosphate limitations, pH of culture medium, aeration, trace elements and morphology of the fungus. Special attention is paid to the fundamentals of biochemistry and accumulation of citric acid. Technologies employed at industrial scale such as surface or submerged cultures, mainly employing Aspergillus niger, and processes carried out with Yarrowia lipolytica, as well as the technology for recovering the product are also described. Finally, this review summarizes the use of orange peels and other by-products as feedstocks for the bioproduction of citric acid. PMID:24031566

  15. Simulated acid rain on crops

    SciTech Connect

    Plocher, M.D.; Perrigan, S.C.; Hevel, R.J.; Cooper, R.M.; Moss, D.N.

    1985-10-01

    In 1981, simulated H/sub 2/SO/sub 4/ acid rain was applied to alfalfa and tall fescue and a 2:1 ratio of H/sub 2/SO/sub 4/:HNO/sub 3/ acid rain was applied to alfalfa, tall fescue, barley, wheat, potato, tomato, radish, and corn crops growing in the open field at Corvallis, Oregon. Careful attention was given to effects of the acid rain on the appearance of the foliage, and the effects on yield were measured. Because the effect of pH 4.0 rain on corn yield was the only significant effect noted in the 1981 studies, in 1982, more-extensive studies of the effect of simulated H/sub 2/SO/sub 4//HNO/sub 3/ rain on corn were conducted. No significant effects of acid rain were found on foliage appearance, or on yield of grain or stover in the 1982 studies.

  16. [Treatment of hydrofluoric acid burns].

    PubMed

    Thiele, B; Winter, U J; Mahrle, G; Steigleder, G K

    1986-01-31

    A chemical-plant worker sustained hydrofluoric acid burns during cleaning procedures. Intra-arterial perfusion and intralesional injections of calcium gluconate solution prevented progression of the burns into deeper tissue layers. PMID:3943470

  17. Making cents of acid recovery

    SciTech Connect

    Ondrey, G.; Shanley, A.

    1993-04-01

    Acid recovery may be expensive, but rising transportation and landfill costs may soon make it the only alternative. Traditionally, acids used in processes from titanium dioxide production to gasoline alkylation and metal pickling were neutralized and discharged into waterways or injected into deep wells. Today, however, discharge permits are being phased out in many countries, and deep well injection is coming under closer scrutiny. An even cheaper option was selling spent acid to fertilizer producers, who used it to dissolve phosphate ores. Health concerns, a depressed fertilizer market and tightening disposal regulations for gypsum byproduct have dried up this option. The paper discusses the processes and costs involved in spent acid regeneration, gypsum-free gas treatments, and problems with explosive contaminants.

  18. EXPOSURE MODELING OF ACID AEROSOLS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) is conducting an intensive characterization and human exposure monitoring program of acid species and related air pollutants in an urban environment. he EPA's Atmospheric Research and Exposure Assessment Laboratory (AREAL) in coopera...

  19. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

    1995-09-12

    An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 10 figs.

  20. Glucaric acids from Leonurus japonicus.

    PubMed

    Jiang, Jianshuang; Li, Yixiu; Feng, Ziming; Yang, Yanan; Zhang, Peicheng

    2015-12-01

    Three new glucaric acids, namely 2-feruloyl-4-syringoyl or 5-feruloyl-3-syringoyl glucaric acid (1), 2-syringoyl-4-feruloyl or 5-syringoyl-3-feruloyl glucaric acid (2), and 3-feruloyl-4-syringoyl or 4-feruloyl-3-syringoyl glucaric acid (3), were isolated from Leonurus japonicus Houtt. Their structures were elucidated by detailed spectroscopic means including UV, IR, HR-ESI-MS, 1D and 2D NMR data spectra. The bioactive assays of compounds 1-3 against hepatoprotection activity were determined. The result suggested that compound 2 exhibited a moderate hepatoprotection activity and the cell survival rate was 74% (10(-5)mol/L), using bicyclol (survival rate: 66%, 10(-5)mol/L) as a positive control. Furthermore, compounds 1-3 were evaluated cytotoxic activities in vitro using HCT-8, Bel-7402, BGC-823, A-549, and A2780 model and the results exhibited no obvious cytotoxicity activity. PMID:26526024

  1. Acid diffusion through polymer films

    NASA Astrophysics Data System (ADS)

    Zhang, P. Linda; Eckert, Andrew R.; Willson, C. Grant; Webber, Stephen E.; Byers, Jeffrey D.

    1997-07-01

    In order to perform 0.2 micrometer processes, one needs to study the diffusion of photoacid generators within the photoresist system, since diffusion during post exposure bake time has an influence on the critical dimension (CD). We have developed a new method to study the diffusion of photoacid generators within a polymer film. This new method is based on monitoring the change of the fluorescence intensity of a pH- sensitive fluorescent dye caused by the reaction with photoacid. A simplified version of this experiment has been conducted by introducing acid vapor to quench the fluorescence intensity of this pH sensor. A thin polymer film is spin cast onto the sensor to create a barrier to the acid diffusion process. During the acid diffusion process, the fluorescence intensity of this pH sensor is measured in situ, using excitation and emission wavelengths at 466 nm and 516 nm, respectively. Fluoresceinamine, the pH sensitive fluorescent dye, is covalently bonded onto the treated quartz substrate to form a single dye layer. Poly(hydroxystyrene) (Mn equals 13k, Tg equals 180 degrees Celsius) in PGMEA (5% - 18% by weight) is spin cast onto this quartz substrate to form films with varying thickness. The soft bake time is 60 seconds at 90 degrees Celsius and a typical film has a thickness of 1.4 micrometers. Trifluoroacetic acid is introduced into a small chamber while the fluorescence from this quartz window is observed. Our study focuses on finding the diffusion constant of the vaporized acid (trifluoroacetic acid) in the poly(hydroxystyrene) polymer film. By applying the Fick's second law, (It - Io)/(I(infinity ) - Io) equals erfc [L/(Dt)1/2] is obtained. The change of fluorescence intensity with respect to the diffusion time is monitored. The above equation is used for the data analysis, where L represents the film thickness and t represents the average time for the acid to diffuse through the film. The diffusion constant is calculated to be at the order of 10

  2. Nucleic acid arrays and methods of synthesis

    DOEpatents

    Sabanayagam, Chandran R.; Sano, Takeshi; Misasi, John; Hatch, Anson; Cantor, Charles

    2001-01-01

    The present invention generally relates to high density nucleic acid arrays and methods of synthesizing nucleic acid sequences on a solid surface. Specifically, the present invention contemplates the use of stabilized nucleic acid primer sequences immobilized on solid surfaces, and circular nucleic acid sequence templates combined with the use of isothermal rolling circle amplification to thereby increase nucleic acid sequence concentrations in a sample or on an array of nucleic acid sequences.

  3. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  4. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and....1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid oxidation of cyclohexanol...

  5. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  6. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...

  7. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  8. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  9. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...

  10. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and....1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It is commercially prepared...

  11. 40 CFR 721.10512 - Fatty acid maleic acid amides (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fatty acid maleic acid amides (generic... Specific Chemical Substances § 721.10512 Fatty acid maleic acid amides (generic). (a) Chemical substance... fatty acid maleic acid amides (PMNs P-07-563 and P-07-564) are subject to reporting under this...

  12. 40 CFR 721.10512 - Fatty acid maleic acid amides (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fatty acid maleic acid amides (generic... Specific Chemical Substances § 721.10512 Fatty acid maleic acid amides (generic). (a) Chemical substance... fatty acid maleic acid amides (PMNs P-07-563 and P-07-564) are subject to reporting under this...

  13. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  14. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  15. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  16. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  17. Aqueous Photochemistry of Glyoxylic Acid.

    PubMed

    Eugene, Alexis J; Xia, Sha-Sha; Guzman, Marcelo I

    2016-06-01

    Aerosols affect climate change, the energy balance of the atmosphere, and public health due to their variable chemical composition, size, and shape. While the formation of secondary organic aerosols (SOA) from gas phase precursors is relatively well understood, studying aqueous chemical reactions contributing to the total SOA budget is the current focus of major attention. Field measurements have revealed that mono-, di-, and oxo-carboxylic acids are abundant species present in SOA and atmospheric waters. This work explores the fate of one of these 2-oxocarboxylic acids, glyoxylic acid, which can photogenerate reactive species under solar irradiation. Additionally, the dark thermal aging of photoproducts is studied by UV-visible and fluorescence spectroscopies to reveal that the optical properties are altered by the glyoxal produced. The optical properties display periodicity in the time domain of the UV-visible spectrum of chromophores with absorption enhancement (thermochromism) or loss (photobleaching) during nighttime and daytime cycles, respectively. During irradiation, excited state glyoxylic acid can undergo α-cleavage or participate in hydrogen abstractions. The use of (13)C nuclear magnetic resonance spectroscopy (NMR) analysis shows that glyoxal is an important intermediate produced during direct photolysis. Glyoxal quickly reaches a quasi-steady state as confirmed by UHPLC-MS analysis of its corresponding (E) and (Z) 2,4-dinitrophenylhydrazones. The homolytic cleavage of glyoxylic acid is proposed as a fundamental step for the production of glyoxal. Both carbon oxides, CO2(g) and CO(g) evolving to the gas-phase, are quantified by FTIR spectroscopy. Finally, formic acid, oxalic acid, and tartaric acid photoproducts are identified by ion chromatography (IC) with conductivity and electrospray (ESI) mass spectrometry (MS) detection and (1)H NMR spectroscopy. A reaction mechanism is proposed based on all experimental observations. PMID:27192089

  18. Chemical composition of acid fog

    SciTech Connect

    Waldman, J.M.; Munger, J.W.; Jacob, D.J.; Flagan, R.C.; Morgan, J.J.; Hoffmann, M.R.

    1982-11-12

    Fog water collected at three sites in Los Angeles and Bakersfield, California, was found to have higher acidity and higher concentrations of sulfate, nitrate, and ammonium than previously observed in atmospheric water droplets. The pH of the fog water was in the range of 2.2 to 4.0. the dominant processes controlling the fog water chemistry appear to be the condensation and evaporation of water vapor on preexisting aerosol and the scavenging of gas-phase nitric acid.

  19. Bile acids as metabolic regulators

    PubMed Central

    Li, Tiangang; Chiang, John Y. L.

    2015-01-01

    Summary Small molecule ligands that target to TGR5 and FXR have shown promise in treating various metabolic and inflammation-related human diseases. New insights into the mechanisms underlying the bariatric surgery and bile acid sequestrant treatment suggest that targeting the enterohepatic circulation to modulate gut-liver bile acid signaling, incretin production and microbiota represents a new strategy to treat obesity and type-2 diabetes. PMID:25584736

  20. Acidic extracellular microenvironment and cancer

    PubMed Central

    2013-01-01

    Acidic extracellular pH is a major feature of tumor tissue, extracellular acidification being primarily considered to be due to lactate secretion from anaerobic glycolysis. Clinicopathological evidence shows that transporters and pumps contribute to H+ secretion, such as the Na+/H+ exchanger, the H+-lactate co-transporter, monocarboxylate transporters, and the proton pump (H+-ATPase); these may also be associated with tumor metastasis. An acidic extracellular pH not only activates secreted lysosomal enzymes that have an optimal pH in the acidic range, but induces the expression of certain genes of pro-metastatic factors through an intracellular signaling cascade that is different from hypoxia. In addition to lactate, CO2 from the pentose phosphate pathway is an alternative source of acidity, showing that hypoxia and extracellular acidity are, while being independent from each other, deeply associated with the cellular microenvironment. In this article, the importance of an acidic extracellular pH as a microenvironmental factor participating in tumor progression is reviewed. PMID:24004445

  1. Photodissociation dynamics of hydroxybenzoic acids

    SciTech Connect

    Yang Yilin; Dyakov, Yuri; Lee, Y. T.; Ni, Chi-Kung; Sun Yilun; Hu Weiping

    2011-01-21

    Aromatic amino acids have large UV absorption cross-sections and low fluorescence quantum yields. Ultrafast internal conversion, which transforms electronic excitation energy to vibrational energy, was assumed to account for the photostability of amino acids. Recent theoretical and experimental investigations suggested that low fluorescence quantum yields of phenol (chromophore of tyrosine) are due to the dissociation from a repulsive excited state. Radicals generated from dissociation may undergo undesired reactions. It contradicts the observed photostability of amino acids. In this work, we explored the photodissociation dynamics of the tyrosine chromophores, 2-, 3- and 4-hydroxybenzoic acid in a molecular beam at 193 nm using multimass ion imaging techniques. We demonstrated that dissociation from the excited state is effectively quenched for the conformers of hydroxybenzoic acids with intramolecular hydrogen bonding. Ab initio calculations show that the excited state and the ground state potential energy surfaces change significantly for the conformers with intramolecular hydrogen bonding. It shows the importance of intramolecular hydrogen bond in the excited state dynamics and provides an alternative molecular mechanism for the photostability of aromatic amino acids upon irradiation of ultraviolet photons.

  2. Evaluation of ascorbic acid in protecting labile folic acid derivatives.

    PubMed Central

    Wilson, S D; Horne, D W

    1983-01-01

    The use of ascorbic acid as a reducing agent to protect labile, reduced derivatives of folic acid has been evaluated by high-performance liquid chromatographic separations and Lactobacillus casei microbiological assay of eluate fractions. Upon heating for 10 min at 100 degrees C, solutions of tetrahydropteroylglutamic acid (H4PteGlu) in 2% sodium ascorbate gave rise to 5,10-methylene-H4PteGlu and 5-methyl-H4PteGlu. H2PteGlu acid gave rise to 5-methyl-H4PteGlu and PteGlu. 10-Formyl-H4PteGlu gave rise to 5-formyl-H4PteGlu and 10-formyl-PteGlu. 5-Formyl-H4-PteGlu gave rise to a small amount of 10-formyl-PteGlu. 5-Methyl-H4PteGlu and PteGlu appeared stable to these conditions. These interconversions were not seen when solutions of these folate derivatives were kept at 0 degrees C in 1% ascorbate. These observations indicate that elevated temperatures are necessary for the interconversions of folates in ascorbate solutions. Assays of ascorbic acid solutions indicated the presence of formaldehyde (approximately equal to 6 mM). This was confirmed by the identification of 3,5-diacetyl-1,4-dihydrolutidine by UV, visible, and fluorescence spectroscopy and by thin-layer chromatography of chloroform extracts of the reaction mixture of ascorbic acid solutions, acetylacetone, and ammonium acetate. These results indicate that solutions of sodium ascorbate used at elevated temperatures are not suitable for extracting tissue for the subsequent assay of the individual folic acid derivatives. PMID:6415653

  3. Gas-Phase Acidities of Phosphorylated Amino Acids.

    PubMed

    Stover, Michele L; Plummer, Chelsea E; Miller, Sean R; Cassady, Carolyn J; Dixon, David A

    2015-11-19

    Gas-phase acidities and heats of formation have been predicted at the G3(MP2)/SCRF-COSMO level of theory for 10 phosphorylated amino acids and their corresponding amides, including phospho-serine (pSer), -threonine (pThr), and -tyrosine (pTyr), providing the first reliable set of these values. The gas-phase acidities (GAs) of the three named phosphorylated amino acids and their amides have been determined using proton transfer reactions in a Fourier transform ion cyclotron mass spectrometer. Excellent agreement was found between the experimental and predicted GAs. The phosphate group is the deprotonation site for pSer and pThr and deprotonation from the carboxylic acid generated the lowest energy anion for pTyr. The infrared spectra were calculated for six low energy anions of pSer, pThr, and pTyr. For deprotonated pSer and pThr, good agreement is found between the experimental IRMPD spectra and the calculated spectra for our lowest energy anion structure. For pTyr, the IR spectra for a higher energy phosphate deprotonated structure is in good agreement with experiment. Additional experiments tested electrospray ionization (ESI) conditions for pTyr and determined that variations in solvent, temperature, and voltage can result in a different experimental GA value, indicating that ESI conditions affect the conformation of the pTyr anion. PMID:26492552

  4. Recovery of uranium from acid media by macroporous bifunctional phosphinic acid resin

    SciTech Connect

    Sabharwal, K.N.; Srinivasan, T.G.; Rao, P.R.V.; Nandy, K.K.

    1996-11-01

    The extraction of uranium from various acid media such as nitric acid, sulphuric acid, hydrochloric acid, phosphoric acid and perchloric acid by a macroporous bifunctional phosphinic acid resin (MPBPA) has been studied. The distribution coefficients for the extraction of uranium by the MPBPA resin are compared with the corresponding values reported in literature for the conventional sulphonic acid resin. The results clearly indicate the suitability of the MPBPA resin to recover uranium from different types of acid solutions of widely ranging acidities. 17 refs., 6 figs., 5 tabs.

  5. Extractive fermentation of acetic acid

    SciTech Connect

    Busche, R.M.

    1991-12-31

    In this technoeconomic evaluation of the manufacture of acetic acid by fermentation, the use of the bacterium: Acetobacter suboxydans from the old vinegar process was compared with expected performance of the newer Clostridium thermoaceticum bacterium. Both systems were projected to operate as immobilized cells in a continuous, fluidized bed bioreactor, using solvent extraction to recover the product. Acetobacter metabolizes ethanol aerobically to produce acid at 100 g/L in a low pH medium. This ensures that the product is in the form of a concentrated extractable free acid, rather than as an unextractable salt. Unfortunately, yields from glucose by way of the ethanol fermentation are poor, but near the biological limits of the organisms involved. Conversely, C. thermoaceticum is a thermophilic anaerobe that operates at high fermentation rates on glucose at neutral pH to produce acetate salts directly in substantially quantitative yields. However, it is severely inhibited by product, which restricts concentration to a dilute 20 g/L. An improved Acetobacter system operating with recycled cells at 50 g/L appears capable of producing acid at $0.38/lb, as compared with a $0.29/lb price for synthetic acid. However, this system has only a limited margin for process improvement. The present Clostridium system cannot compete, since the required selling price would be $0.42/lb. However, if the organism could be adapted to tolerate higher product concentrations at acid pH, selling price could be reduced to $0.22/lb, or about 80% of the price of synthetic acid.

  6. Anaerobic biotransformation of organoarsenical pesticides monomethylarsonic acid and dimethylarsinic acid

    USGS Publications Warehouse

    Sierra-Alvarez, R.; Yenal, U.; Feld, J.A.; Kopplin, M.; Gandolfi, A.J.; Garbarino, J.R.

    2006-01-01

    Monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) are extensively utilized as pesticides, introducing large quantities of arsenic into the environment. Once released into the environment, these organoarsenicals are subject to microbial reactions. Aerobic biodegradation of MMAV and DMAV has been evaluated, but little is known about their fate in anaerobic environments. The objective of this study was to evaluate the biotransformation of MMAV and DMAV in anaerobic sludge. Biologically mediated conversion occurred under methanogenic or sulfate-reducing conditions but not in the presence of nitrate. Monomethylarsonous acid (MMAIII) was consistently observed as an important metabolite of MMAV degradation, and it was recovered in molar yields ranging from 5 to 47%. The main biotransformation product identified from DMAV metabolism was MMAV, which was recovered in molar yields ranging from 8 to 65%. The metabolites indicate that reduction and demethylation are important steps in the anaerobic bioconversion of MMAV and DMAV, respectively. ?? 2006 American Chemical Society.

  7. Antibodies to Yeast Phenylalanine Transfer Ribonucleic Acid Are Specific for the Odd Nucleoside Y in the Anticodon Loop

    PubMed Central

    Fuchs, Sara; Aharonov, Aharon; Sela, Michael; Von Der Haar, Friedrich; Cramer, Friedrich

    1974-01-01

    Antibodies with specificity to a single species of tRNA were elicited in a goat by immunization with a glutaraldehyde conjugate of yeast phenylalanine transfer RNA with bovine gamma globulin. The specificity of the antibodies was studied by a radioimmunoassay measuring the direct binding of [3H]tRNAPhe or the inhibition of the binding. The antibodies formed are predominantly directed towards the characteristic highly modified nucleoside Y, which is located right next to the anticodon. The antibodies bind specifically to tRNAPhe, to oligonucleotides derived by enzymatic digestion from the anticodon loop of tRNAPhe, and to the Y nucleoside itself. tRNA species which do not contain Y in their sequences, or tRNAPhe from which the Y base has been excised, do not bind to the antibodies. Yeast tRNAPhe can be separated from other tRNA species with an immunoadsorbent of antibodies to tRNAPhe. PMID:4527666

  8. [Effects of colchicine on the content of ribonucleic acids and total proteins of cultured nerve cells. Preliminary study].

    PubMed

    Noel-Courtey, B

    1975-03-01

    Nervous cells from chick embryo lumbo-sacral spinal cord have been cultivated in vitro and treated with colchicine. The effects of this alkaloid on the RNA and the total protein contents of nervous cells have been studied by quantitative cytochemical methods. The RNA content has been measured by cytophotometry after DNase digestion and gallocyanine-chromalun staining; the cellular protein content has been measured after Naphtol Yellow S staining. In colchicine treated cultures, the main part of the nervous cell population consists of spheroidal and piriform neuroblasts; some cells are neurocytes with short processes. During the 48 first hours in vitro, the RNA content is approximatively identical in treated cells as in controls. The cellular total protein content is much lower in the treated cells than in the controls. PMID:1222295

  9. Identification of novel chicken estrogen receptor-alpha messenger ribonucleic acid isoforms generated by alternative splicing and promoter usage.

    PubMed

    Griffin, C; Flouriot, G; Sonntag-Buck, V; Nestor, P; Gannon, F

    1998-11-01

    Using the rapid amplification of complementary DNA ends (RACE) methodology we have identified three new chicken estrogen receptor-alpha (cER alpha) messenger RNA (mRNA) variants in addition to the previously described form (isoform A). Whereas one of the new variants (isoform B) presents a 5'-extremity contiguous to the 5'-end of isoform A, the two other forms (isoforms C and D) are generated by alternative splicing of upstream exons (C and D) to a common site situated 70 nucleotides upstream of the translation start site in the previously assigned exon 1 (A). The 3'-end of exon 1C has been located at position -1334 upstream of the transcription start site of the A isoform (+1). Whereas the genomic location of exon 1D is unknown, 700 bp 5' to this exon were isolated by genomic walking, and their sequence was determined. The transcription start sites of the cER alpha mRNA isoforms were defined. In transfection experiments, the regions immediately upstream of the A-D cER alpha mRNA isoforms were shown to possess cell-specific promoter activities. Three of these promoters were down-regulated in the presence of estradiol and ER alpha protein. It is concluded, therefore, that the expression of the four different cER alpha mRNA isoforms is under the control of four different promoters. Finally, RT-PCR, S1 nuclease mapping, and primer extension analysis of these different cER alpha mRNA isoforms revealed a differential pattern of expression of the cER alpha gene in chicken tissues. Together, the results suggest that alternative 5'-splicing and promoter usage may be mechanisms used to modulate the levels of expression of the chicken ER alpha gene in a tissue-specific and/or developmental stage-specific manner. PMID:9794473

  10. Regulation of insulin-like growth factor-binding protein messenger ribonucleic acid levels in sheep thyroid cells.

    PubMed

    Bachrach, L K; Eggo, M C; Burrow, G N; Liu, F; Tram, T; Powell, D R

    1991-04-01

    The insulin-like growth factors (IGFs) exist primarily bound to cell surface receptors or complexed to specific binding proteins (IGFBPs). The IGFBPs modulate the bioavailability of the IGFs and may enhance or inhibit IGF actions. Several distinct forms of IGFBPs have been described on the basis of size, immunological determinants, and distribution in biological fluids; the IGFBPs may differ as well in their biological function. Sheep thyroid cells produce IGFBPs under hormonal regulation. Cells grown in basal medium or with six-hormone (6H) medium supplements (transferrin, glycyl-histidyl-lysine, hydrocortisone, somatostatin, insulin, and TSH) release nonglycosylated BPs that migrate at 24, 27, 29, and 32 kDa on Western ligand blot. Cells cultured with the thyroid mitogens epidermal growth factor and phorbol ester release additional glycosylated IGFBPs of 40-44 kDa. Immunoprecipitation experiments indicate that 29- and 32-kDa IGFBPs are antigenically related to IGFBP-2, and the 40- to 44-kDa proteins are related to IGFBP-3. Using specific cDNA probes IGFBP-1, -2, and -3, we examined the regulation of IGFBP mRNA levels in sheep thyroid cultures. The rat IGFBP-2 cDNA probe hybridized to an approximately 1.6-kilobase mRNA species in cells under all culture conditions. However, IGFBP-3 mRNA was detectable only in epidermal growth factor- or phorbol ester-treated cells and appeared within 4 h, preceding the release of IGFBP-3 protein into the medium. The 6H additives, which stimulate differentiated function in thyroid cells, inhibited the mRNA levels of both IGFBP-2 and IGFBP-3. IGFBP-1 mRNA was not detectable. The distinct regulation of these IGFBPs suggest that they may play different biological roles in modulating thyroid physiology. PMID:1706262

  11. Glucocorticoid control of rat growth hormone gene expression: Effect on cytoplasmic messenger ribonucleic acid production and degradation

    SciTech Connect

    Gertz, B.J.; Gardner, D.G.; Baxter, J.D. )

    1987-12-01

    The effect of the glucocorticoid dexamethasone on the production and degradation of rat GH (rGH) cytoplasmic mRNA was studied in cultured rat pituitary tumor (GC) cells. The incorporation of (3H)uridine into both rGH cytoplasmic mRNA and the pyrimidine nucleotide precursor pool was determined in hormone-treated and control cells. From these measurements glucocorticoid effects on absolute production rates of rGH cytoplasmic mRNA were determined and compared to effects on rGH mRNA accumulation. Rat GH mRNA half-life was then calculated based on a first-order decay model. Rat GH mRNA half-life was also directly assayed by: (1) pulse-chase studies and (2) measuring the kinetics of decay of rGH mRNA in cells after transfer from serum-containing to hormone-deficient media. From these independent analyses rGH mRNA half-life estimates ranged from 28-55 h in different experiments. Within individual experiments there was little variability of rGH mRNA decay rates; glucocorticoids were found not to alter the stability of rGH cytoplasmic mRNA. Glucocorticoid induction of rGH cytoplasmic mRNA accumulation was accounted for solely on the basis of increased mRNA production.

  12. Effect of hypophysectomy and growth hormone replacement on hypothalamic growth hormone-releasing factor messenger ribonucleic Acid levels.

    PubMed

    Eccleston, L M; Powell, J F; Clayton, R N

    1991-12-01

    Abstract The mechanisms by which the pituitary gland, and growth hormone (GH) in particular, affect growth hormone-releasing factor (GRF) gene expression have been addressed using the technique of in situ hybridization. Anatomically matched sections through the mediobasal hypothalamus of control and hypophysectomized male rats, with or without GH hormone replacement, were analysed to obtain information on GRF mRNA levels within the arcuate nucleus and around the ventromedial hypothalamus. Hypophysectomy resulted in a 70% increase in the amount of GRF mRNA per cell (P<0.001), within neurons in the arcuate nucleus. GH replacement and T4 replacement separately partially attenuated this increase (GH replacement P< 0.001 versus hypophysectomy, T4 replacement P<0.05 versus hypophysectomy). Additionally, after hypophysectomy there was an 80% increase in the number of cells expressing the GRF gene in neurons around the ventromedial hypothalamus, when compared to shamoperated controls (P<0.01). Both GH and T4 replacement separately partially attenuated this phenomenon (P<0.01 versus hypophysectomized animals). Hypothyroidism alone did not affect GRF mRNA levels in either the arcuate nucleus or in the area surrounding the ventromedial hypothalamus. These results show that hypophysectomy increases GRF mRNA levels in two separate ways: by increasing the amount of mRNA produced per cell within the arcuate nucleus, and by increasing the number of cells expressing the gene in the area surrounding the ventromedial hypothalamus. This increase in the number of GRF mRNA-containing cells after hypophysectomy could result from the recruitment of neurons which previously did not express the GRF gene, and may reflect the plasticity of the adult central nervous system in response to a changing endocrine environment. This could represent part of a sensor mechanism to drive the production of GRF in the arcuate nucleus in response to extreme disruption of the GRF/ GH feedback loop. PMID:19215536

  13. Triiodothyronine receptor beta-2 messenger ribonucleic acid expression by somatotropes and thyrotropes: effect of propylthiouracil-induced hypothyroidism in rats.

    PubMed

    Childs, G V; Taub, K; Jones, K E; Chin, W W

    1991-11-01

    mRNA for a thyroid hormone receptor isoform that is unique to the pituitary gland (TR beta-2) is down-regulated by T3. Increases in the expression of this mRNA are seen in rats rendered hypothyroid by treatment with propylthiouracil (PTU). This study used dual labeling to determine which pituitary cells expressed TR beta-2 mRNA in normal and PTU-treated rats. In situ hybridization protocols localized the mRNA (with biotinylated complementary oligonucleotide probes detected by avidin-biotin-peroxidase), and immunoperoxidase protocols identified the pituitary hormone proteins. In dispersed pituitary cells, 20 +/- 2% (average +/- SD) of cells from normal rats and 30 +/- 3% of cells from PTU-treated rats were labeled for TR beta-2 mRNA. PTU caused increases in the area of the labeled cells (from 114 +/- 11 to 225 +/- 7 microns 2), the area of the label per cell (from 27 +/- 3 to 71 +/- 11 microns 2), and label density. PTU produced increases in the percentage of TSH cells from 8 +/- 1% to 19 +/- 2%, decreases in the percentage of GH cells from 27 +/- 3% to 11 +/- 2%, and no change in other cell types. After dual labeling, 73% of cells that expressed TR beta-2 mRNA stored either TSH (35 +/- 8) or GH (38 +/- 6). Less than 10% stored other hormones. When each cell type was analyzed, 56 +/- 3% of TSH cells and 43 +/- 4% of GH cells expressed TR beta-2 mRNA. When these percentages were multiplied by the percentages of each cell type in the overall population, TSH and GH cells with TR beta-2 mRNA represented 6.8 +/- 1% and 11.6 +/- 1% of the pituitary cells, respectively. Less than 1% of all pituitary cells expressed TR beta-2 and ACTH (0.9 +/- 0.06), LH (0.8 +/- 0.1), FSH (0.8 +/- 0.1), and PRL (0.9 +/- 0.04). PTU treatment increased the percentage of TSH cells with TR beta-2 mRNA to 72 +/- 4% and decreased the percentage of GH cells with TR beta-2 mRNA to 30 +/- 3%. However, some enlarged putative TSH cells could not be identified by immunolabel because the storage levels were low. Thus, changes in TR beta-2 mRNA in hypothyroid rats may be the net result of the increase in the percentage of TSH cells, the amount of mRNA per cell (measured by area and density of label), and the decrease in the percentage of GH cells.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1935806

  14. Neurospora crassa glutamine synthetase. Translation of specific messenger ribonucleic acid in a cell-free system derived from rabbit reticulocytes.

    PubMed

    Palacios, R; Campomanes, M; Quinto, C

    1977-05-10

    The total reticulocyte lysate cell-free protein-synthesizing system was incubated in the presence of Neurospora crassa RNA. With the aid of an antibody directed against purified N. crassa glutamine synthetase, the synthesis of a specific protein was detected. This protein precipitates with antiglutamine synthetase using both direct and indirect procedures, migrates with the same molecular weight as the monomer of N. crassa glutamine synthetase when subjected to acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and chromatographs as N. crassa glutamine synthetase on anthranilate-bound Sepharose. These data indicate the translation of the mRNA that codes for N. crassa glutamine synthetase. This RNA behaves as poly(A)-containing material when fractionated on oly(U)-Sepha-rose. PMID:16013

  15. Evidence for ovarian granulosa stem cells: telomerase activity and localization of the telomerase ribonucleic acid component in bovine ovarian follicles.

    PubMed

    Lavranos, T C; Mathis, J M; Latham, S E; Kalionis, B; Shay, J W; Rodgers, R J

    1999-08-01

    We have previously postulated that granulosa cells of developing follicles arise from a population of stem cells. Stem cells and cancer cells can divide indefinitely partly because they express telomerase. Telomerase is a ribonucleoprotein enzyme that repairs the ends of telomeres that otherwise shorten progressively upon each successive cell division. In this study we carried out cell cycle analyses and examined telomerase expression to examine our hypothesis. Preantral (60-100 microm) and small (1 mm) follicles, as well as granulosa cells from medium-sized (3 mm) and large (6-8 mm) follicles, were isolated. Cell cycle analyses and expression of Ki-67, a cell cycle-related protein, were undertaken on follicles of each size (n = 3) by flow cytometry; 12% to 16% of granulosa cells in all follicles were in the S phase, and less than 2% were in the G(2)/M phase. Telomerase activity (n = 3) was highest in the small preantral follicles, declining at the 1-mm stage and even further at the 3-mm stage. In situ hybridization histochemistry was carried out on bovine ovaries, and telomerase RNA was detected in the granulosa cells of growing follicles but not primordial follicles. Two major patterns of staining were observed in the membrana granulosa of antral follicles: staining in the middle and antral layers, and staining in the middle and basal layers. No staining was detected in oocytes. Our results strongly support our hypothesis that granulosa cells arise from a population of stem cells. PMID:10411512

  16. Endothelin in human brain and pituitary gland: Presence of immunoreactive endothelin, endothelin messenger ribonucleic acid, and endothelin receptors

    SciTech Connect

    Takahashi, K.; Ghatei, M.A.; Jones, P.M.; Murphy, J.K.; Lam, H.C.; O'Halloran, D.J.; Bloom, S.R. )

    1991-03-01

    The presence of immunoreactive (IR) endothelin, endothelin mRNA, and endothelin receptors in human brain and pituitary gland has been studied by RIA, Northern blot hybridization, and receptor assay. IR endothelin was detected in all five brain regions examined (cerebral cortex, cerebellum, brain stem, basal ganglia, and hypothalamus) (6-10 fmol/g wet wt) and spinal cord (22 +/- 6 fmol/g wet wt, n = 7, mean +/- SEM). Higher concentrations of IR endothelin were found in the pituitary gland (147 +/- 30 fmol/g wet wt). Fast protein liquid chromatographic analysis of the IR endothelin in pituitary gland showed a large IR peak in the position of endothelin-3 and a smaller peak in the position of endothelin-1, whereas IR endothelin in the hypothalamus and brain stem was mainly endothelin-1. Endothelin messenger RNA was detected by Northern blot hybridization in the pituitary but not in hypothalamus. The receptor assay showed that 125I-endothelin-1 binding sites were present in large numbers in all five brain regions but were much less abundant in the pituitary gland. Binding capacity and dissociation constant were 5052 +/- 740 fmol/mg protein and 0.045 +/- 0.007 nM in brain stem and 963 +/- 181 fmol/mg protein and 0.034 +/- 0.009 nM in hypothalamus. In the pituitary gland, there were two classes of binding sites for endothelin with dissociation constants of 0.059 +/- 0.002 nM (binding capacity = 418 +/- 63 fmol/mg protein) and 0.652 +/- 0.103 nM (binding capacity = 1717 +/- 200 fmol/mg protein). Endothelin-1, -2 and -3 were almost equipotent in displacing the binding (IC50 approximately 0.04 nM). These findings are in accord with the possibility that endothelin acts as a neurotransmitter, neuromodulator or neurohormone in man.

  17. Polyriboadenylate Sequences at the 3′-Termini of Ribonucleic Acid Obtained from Mammalian Leukemia and Sarcoma Viruses

    PubMed Central

    Phillips, Leo A.; Park, James J.; Hollis, Vincent W.

    1974-01-01

    The location of poly(A) sequences in the RNA of mammalian RNA-tumor viruses was determined by enzymatic analyses. The 56-64S viral genomic RNAs, the 20-40S viral subunit RNAs, and the 4-5S poly(A) sequences excised from these viral RNAs were subjected to either hydrolysis with a 3′-OH specific exoribonuclease from Ehrlich ascites tumor cells or phosphorolysis from the 3′-termini with polynucleotide phosphorylase from Micrococcus luteus. Purified adenosine-labeled poly(A) fragments, excised from genomic viral RNAs by RNase A and T1 digestion, were hydrolyzed with the 3′-OH specific exoribonuclease for various periods of time. Poly(U) filter binding studies of the residual poly(A) indicated that 97% of the poly(A) fragments were hydrolyzed. Adenosine-labeled genomic and subunit viral RNAs and excised poly(A) fragments were phosphorolyzed from their 3′-termini for various periods of time with polynucleotide phosphorylase. The degree of phosphorolysis was monitored by poly(U) filter binding studies, and CCl3COOH insolubility and solubility determinations. There was an initial preferential rate of phosphorolysis of the poly(A) sequences of genomic and subunit viral RNAs as compared to the total adenosine-labeled viral RNAs. The data from these two different enzymatic mechanisms of action indicated conclusively that the poly(A) sequences were located at the 3′-termini of genomic and subunit viral RNAs. PMID:4373712

  18. Effects of irradiation and semistarvation on rat thyrotropin beta subunit messenger ribonucleic acid, pituitary thyrotropin content, and thyroid hormone levels

    SciTech Connect

    Litten, R.Z. ); Carr, F.E. ); Fein, H.G.; Smallridge, R.C. )

    1990-01-01

    The effect of radiation-induced anorexia on serum thyrotropin (TSH), pituitary TSH-{beta} mRNA, pituitary TSH content, serum thyroxine (T{sub 4}), and serum 3,5,3{prime}-triiodothyronine (T{sub 3}) was investigated using feed-matched controls. Rats received 10 Gy gamma whole-body irradiation and were examined 1-3 days postirradiation. Feed-matched and untreated controls were also studied. The average food intake of the irradiated and feed-matched groups was approximately 18% of the untreated controls. Over the three day period both the irradiated and feed-matched groups lost a significant amount of body weight. The serum T{sub 4} levels of both the irradiated and feed-matched groups were not significantly different from each other, but were significantly depressed when compared to the untreated control group. The serum TSH and T{sub 3} were, however, significantly greater in the irradiated than the feed-matched groups at day 3 posttreatment. To determine if the difference in the serum TSH level between the two groups was due to a pretranslational alteration in TSH production, we measured the TSH-{beta} mRNA using an RNA blot hybridization assay. We found that the TSH-{beta} mRNA level was the same in the irradiated and feed-matched groups, suggesting that the mechanism responsible for the radiation-induced increase in the serum TSH level is posttranscriptional. Pituitary TSH content in the irradiated rats was significantly less than in pair-fed controls, suggesting that irradiation may permit enhanced secretion of stored hormone.

  19. A study of the alkaline hydrolysis of fractionated reticulocyte ribosomal ribonucleic acid and its relevance to secondary structure

    PubMed Central

    Cox, R. A.; Gould, Hannah J.; Kanagalingam, K.

    1968-01-01

    1. RNA isolated from the sub-units of rabbit reticulocyte ribosomes was hydrolysed by 0·4n-potassium hydroxide at 20°. The probability of main-chain scission was calculated from the number-average chain length, which was obtained from S25,w in 0·01m-phosphate buffer. 2. The fraction, f, of the original secondary structure that the fragments re-formed at neutral pH in 4m-guanidinium chloride, as well as in 0·01m- and 0·1m-phosphate buffer, was derived from changes in extinction over the range 220–310mμ on thermal denaturation. 3. The secondary structure of RNA is regarded as an assembly of hairpin loops each of 2N+b residues on average, where N is the number of base-paired residues and b is the number of unpaired residues. 4. If chain scission takes place at random then 2N+b=logf/log(1–p). 5. For RNA from the smaller sub-unit 2N+b was estimated as 25±5 residues, compared with 30±5 residues for the less stable species and 35±5 residues for the more stable species of hairpin loop of RNA from the larger sub-unit. PMID:5639928

  20. Ribonucleic Acid Synthesis in Cells Infected with Herpes Simplex Virus: Controls of Transcription and of RNA Abundance*

    PubMed Central

    Frenkel, Niza; Roizman, Bernard

    1972-01-01

    Analysis of the kinetics of hybridization in liquid of labeled herpes simplex virus-1 DNA and excess viral RNA revealed the following: (i) Cells infected by herpes simplex virus-1 for 2 hr (before DNA synthesis) contain two classes of RNA molecules differing 140-fold in molar concentrations. The abundant and scarce RNAs are transcribed from 14 and 30% of the DNA, respectively. RNA extracted at 8 hr after infection (late RNA) also contains abundant and scarce classes differing 40-fold in molar concentrations; these are transcribed from 19 and 28% of viral DNA, respectively. Abundance competition hybridization tests indicate that the abundant RNA at 2 hr is a subset of the 8-hr abundant RNA. (ii) The abundant RNAs probably specify structural proteins, as indicated by estimates of DNA template required for structural proteins and by experiments showing that 19 of 24 proteins (corresponding to 68% of genetic information for structural proteins) are already made between 0.5 and 2 hr after infection. We conclude that there are two types of transcriptional controls, i.e., on-off and abundance controls, and that the synthesis of most structural components is an early viral function. PMID:4341703