WorldWideScience

Sample records for soluble deoxyribonucleic acid

  1. High mobility organic field-effect transistor based on water-soluble deoxyribonucleic acid via spray coating

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wei; Han, Shijiao; Huang, Wei; Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2015-01-26

    High mobility organic field-effect transistors (OFETs) by inserting water-soluble deoxyribonucleic acid (DNA) buffer layer between electrodes and pentacene film through spray coating process were fabricated. Compared with the OFETs incorporated with DNA in the conventional organic solvents of ethanol and methanol: water mixture, the water-soluble DNA based OFET exhibited an over four folds enhancement of field-effect mobility from 0.035 to 0.153 cm{sup 2}/Vs. By characterizing the surface morphology and the crystalline structure of pentacene active layer through atomic force microscope and X-ray diffraction, it was found that the adoption of water solvent in DNA solution, which played a key role in enhancing the field-effect mobility, was ascribed to both the elimination of the irreversible organic solvent-induced bulk-like phase transition of pentacene film and the diminution of a majority of charge trapping at interfaces in OFETs.

  2. Extrachromosomal deoxyribonucleic acid in R factor-harboring Enterobacteriaceae

    DEFF Research Database (Denmark)

    Møller, JK; Bak, AL; Christiansen, C

    1976-01-01

    Extrachromosomal deoxyribonucleic acid (DNA) from 24 different R factor-harboring Enterobacteriaceae was isolated and characterized by analytical ultracentrifugation and electron microscopy. The R factors represented 15 different patterns of transferable drug resistance found in enterobacteria from...

  3. Deoxyribonucleic acid-deficient strains of Candida albicans.

    OpenAIRE

    Olaiya, A F; Steed, J R; Sogin, S J

    1980-01-01

    We analyzed a series of germ tube-negative variants isolated from Candida albicans 3153A for deoxyribonucleic acid content. As analyzed by flow microfluorometry, the deoxyribonucleic acid level in these variant strains was 50% of that of the parental strain and equivalent to that of haploid Saccharomyces cerevisiae. This finding was confirmed by comparison of survival rates when exposed to the mutagens ultraviolet light, ethyl methane sulfonate, and methyl methane sulfonate. The diameter of t...

  4. Deoxyribonucleic acid-deficient strains of Candida albicans.

    Science.gov (United States)

    Olaiya, A F; Steed, J R; Sogin, S J

    1980-03-01

    We analyzed a series of germ tube-negative variants isolated from Candida albicans 3153A for deoxyribonucleic acid content. As analyzed by flow microfluorometry, the deoxyribonucleic acid level in these variant strains was 50% of that of the parental strain and equivalent to that of haploid Saccharomyces cerevisiae. This finding was confirmed by comparison of survival rates when exposed to the mutagens ultraviolet light, ethyl methane sulfonate, and methyl methane sulfonate. The diameter of the variant cells as compared to the diameter of the parental 3153A strain showed a relationship similar to that of the diameters of haploid versus diploid S. cerevisiae. These results indicate that those strains may be representative of the imperfect stage of C. albicans.

  5. Deoxyribonucleic Acid Probes Analyses for the Detection of Periodontal Pathogens.

    Science.gov (United States)

    Al Yahfoufi, Zoubeida; Hadchiti, Wahib; Berberi, Antoine

    2015-09-01

    In clinical microbiology several techniques have been used to identify bacteria. Recently, Deoxyribonucleic acid (DNA)-based techniques have been introduced to detect human microbial pathogens in periodontal diseases. Deoxyribonucleic acid probes can detect bacteria at a very low level if we compared with the culture methods. These probes have shown rapid and cost-effective microbial diagnosis, good sensitivity and specificity for some periodontal pathogens in cases of severe periodontitis. Eighty-five patients were recruited for the study. Twenty-one subjects ranging between 22 and 48 years of age fulfilled the inclusion and exclusion criteria. Seventy-eight samples became available for DNA probe analysis from the deepest pockets in each quadrant. All 21 patients showed positive results for Prevotella intermedia; also, Prevotella gingivalis was identified in 19 subjects, Aggregatibacter actinomycetemcomitans in 6 subjects. P. intermedia was diagnosed positive in 82% of the subgingival samples taken, 79% for P. gingivalis, and 23% for A. actinomycetemcomitans. This study shows a high frequency of putative periodontal pathogens by using DNA probe technology, which is semi-quantitative in this study. Deoxyribonucleic acid probes can detect bacteria at very low level about 10(3) which is below the detection level of culture methods. The detection threshold of cultural methods. The three types of bacteria can be detected rapidly with high sensitivity by using the DNA probe by general practitioners, and thus can help in the diagnosis process and the treatment.

  6. Extrachromosomal deoxyribonucleic acid in R factor-harboring Enterobacteriaceae

    DEFF Research Database (Denmark)

    Møller, JK; Bak, AL; Christiansen, C

    1976-01-01

    Extrachromosomal deoxyribonucleic acid (DNA) from 24 different R factor-harboring Enterobacteriaceae was isolated and characterized by analytical ultracentrifugation and electron microscopy. The R factors represented 15 different patterns of transferable drug resistance found in enterobacteria from...... from 1.700 to 1.720 g/cm3. The majority of the bacteria contained extrachromosomal DNAs of various densities. Three-fourths of the R factors were classified as fi+. The investigation illustrates the extensive variability in the physical characteristics of plasmid DNA from R factor-harboring strains....

  7. Nature of transforming deoxyribonucleic acid in calcium-treated Escherichia coli

    International Nuclear Information System (INIS)

    Strike, P.; Humphreys, G.O.; Roberts, R.J.

    1979-01-01

    A study of the reactivation of ultraviolet-irradiated plasmid and phage deoxyribonucleic acid molecules after transformation into Escherichia coli strains indicated that, when double-stranded deoxyribonucleic acid was used as the donor species, it was taken up without conversion to the single-stranded form

  8. Effect of deoxyribonucleic acid replication inhibitors on bacterial recombination

    International Nuclear Information System (INIS)

    Canosi, U.; Siccardi, A.G.; Falaschi, A.; Mazza, G.

    1976-01-01

    Two inhibitors of replicative deoxyribonucleic acid (DNA) synthesis, nalidixic acid (NAL) and 6-(p-hydroxyphenylazo)-uracil (HPUra), showed different effects on genetic recombination and DNA repair in Bacillus subtilis. Previous work (Pedrini et al., 1972) showed that NAL does not interfere with the transformation process of B. subtilis. The results reported in this work demonstrated that the drug was also without effect on the transfection SPP1 or SPO-1 phage DNA (a process that requires a recombination event). The drug was also ineffective on the host cell reactivation of ultraviolet-irradiated SPP1 phage, as well as on transfection with ultraviolet-irradiated DNA of the same phage. HPUra instead markedly reduced the transformation process, as well as transfection, by SPO-1 DNA, but it did not affect the host cell reactivation of SPO-1 phage. In conclusion, whereas the NAL target seems to be specific for replicative DNA synthesis, the HPUra target (i.e., the DNA polymerase III of B. subtilis) seems to be involved also in recombination, but not in the excision repair process. The mutations conferring NAL and HPUra resistance used in this work were mapped by PBS-1 transduction

  9. Lidocaine and ropivacaine, but not bupivacaine, demethylate deoxyribonucleic acid in breast cancer cells in vitro

    NARCIS (Netherlands)

    Lirk, P.; Hollmann, M. W.; Fleischer, M.; Weber, N. C.; Fiegl, H.

    2014-01-01

    Lidocaine demethylates deoxyribonucleic acid (DNA) in breast cancer cells. This modification of epigenetic information may be of therapeutic relevance in the perioperative period, because a decrease in methylation can reactivate tumour suppressor genes and inhibit tumour growth. The objectives of

  10. Uracil in formic acid hydrolysates of deoxyribonucleic acid

    Science.gov (United States)

    Schein, Arnold H.

    1966-01-01

    1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

  11. Electrochemical sensing of tumor suppressor protein p53-deoxyribonucleic acid complex stability at an electrified interface

    Czech Academy of Sciences Publication Activity Database

    Paleček, Emil; Černocká, Hana; Ostatná, Veronika; Navrátilová, Lucie; Brázdová, Marie

    2014-01-01

    Roč. 828, MAY2014 (2014), s. 1-8 ISSN 0003-2670 R&D Projects: GA ČR(CZ) GAP301/11/2055; GA ČR(CZ) GA13-00956S; GA ČR(CZ) GA13-36108S Institutional support: RVO:68081707 Keywords : Deoxyribonucleic acid-protein binding * Tumor suppressor protein p53 * Electrochemical sensing Subject RIV: BO - Biophysics Impact factor: 4.513, year: 2014

  12. The effects of ionizing radiation on deoxyribonucleic acid

    International Nuclear Information System (INIS)

    Cullis, P.M.; Jones, G.D.D.; Lea, J.; Symons, M.C.R.; Sweeney, M.

    1987-01-01

    Exposure of frozen, deoxygenated, aqueous solutions of DNA to 60 Co γ-rays at 77 K results in the formation of guanine-centred radical-cations (Gsup(radical +)) and thymine-centred radical-anions (Tsup(radical -)). Both these primary centres are thought to be capable of inducing DNA strand-breaks, both single (SSB) and double (DSB). When low concentrations of a range of water-soluble thiols were added, there was no change in the initial yield of Gsup(radical +) and Tsup(radical -) as judged from the e.s.r. spectra. However, on annealing, the normal pattern of radical reactions was abruptly modified at ca. 200 ± 5 K, with the DNA-centred radicals being dramatically reduced in concentration with the concomitant growth of e.s.r. signals characteristic of RSsup(radical) - SR - radical-anions. For example, for solutions containing one thiol molecule per 25 base-pairs, there was a loss of ca. 50% in the concentration of DNA radicals at this temperature. Using plasmid DNA, the change in the numbers of SSBs and DSBs was monitored when various thiols were present. There was a marked fall in the yields of both these events, in accord with the e.s.r. results. It is concluded that these thiols react by hydrogen-atom donation to various DNA radicals thereby forming RSsup(radical) radicals which rapidly form RSsup(radical)SR - radical-anions. It seems that, under our conditions, neither of these sulphur radicals is able to react with DNA. In the presence of oxygen, the results are less definitive, the degree of repair being a function of the relative concentrations of oxygen and thiol. E.s.r. evidence for the formation of DNA-centred peroxy radicals and their reaction with thiols is presented, and also there is evidence for the addition of oxygen to RSsup(radical) radicals to give RSOsup(anion radical) 2 radicals. The latter are probably able to react with DNA. (author)

  13. Quantitative determination of deoxyribonucleic acid in rat brain

    Science.gov (United States)

    Penn, N. W.; Suwalski, R.

    1969-01-01

    1. A procedure is given for spectrophotometric analysis of rat brain DNA after its resolution into component bases. Amounts of tissue in the range 50–100mg. can be used. 2. The amount of DNA obtained by the present method is 80% greater than that reported for rat brain by a previous procedure specific for DNA thymine. Identity of the material is established by the base ratios of purines and pyrimidines. The features responsible for the higher yield are the presence of dioxan during alkaline hydrolysis of tissue, the determination of the optimum concentration of potassium hydroxide in this step and omission of organic washes of the initial acid-precipitated residues. 3. The requirement for dioxan during alkaline hydrolysis suggests a possible association of brain DNA with lipid. The concentration of potassium hydroxide that gives maximum yield is 0·1m, indicating that there may be internucleotide linkages in this DNA that are more sensitive to alkali than those of liver or thymus DNA. 4. This procedure gives low yields of DNA from liver. It is not suitable for analysis of the DNA from this tissue. PMID:5353529

  14. Ultraviolet electroluminescence from zinc oxide nanorods/deoxyribonucleic acid hybrid bio light-emitting diode

    Science.gov (United States)

    Gupta, Rohini Bhardwaj; Nagpal, Swati; Arora, Swati; Bhatnagar, Pramod Kumar; Mathur, Parmatma Chandra

    2011-01-01

    Ultraviolet (UV) light-emitting diode using salmon deoxyribonucleic acid (sDNA)-cetyltrimethylammonium complex as an electron blocking layer and zinc oxide (ZnO) nanorods as emissive material was fabricated. UV emission, which was blue shifted up to 335 nm with respect to the band edge emission of 390 nm, was observed. This blue shift was caused due to accumulation of electrons in the conduction band of ZnO because of a high potential barrier existing at the sDNA/ZnO interface.

  15. Genetic Control of the Secondary Modification of Deoxyribonucleic Acid in Escherichia coli1

    Science.gov (United States)

    Mamelak, Linda; Boyer, Herbert W.

    1970-01-01

    The wild-type restriction and modification alleles of Escherichia coli K-12 and B were found to have no measurable effect on the patterns of methylated bases in the deoxyribonucleic acid (DNA) of these strains. The genetic region controlling the methylation of cytosine in E. coli K-12 was mapped close to his, and the presence or absence of this gene in E. coli B or E. coli K had no effect on the restriction and modification properties of these strains. Thus, only a few of the methylated bases in the DNA of these strains are involved in host modification, and the biological role of the remainder remains obscure. PMID:4919756

  16. Breaks induced in the deoxyribonucleic acid of aerosolized Escherichia coli by ozonized cyclohexene.

    Science.gov (United States)

    De Mik, G; De Groot, I

    1978-01-01

    The inactivation of aerosolized Escherichia coli by ozone, cyclohexene, and ozonized cyclohexene was studied. The parameters for damage were loss of reproduction and introduction of breaks in the deoxyribonucleic acid (DNA). Aerosolization of E. coli in clean air at 80 percent relative humidity or in air containing either ozone or cyclohexene hardly affected survival; however, some breaks per DNA molecule were induced, as shown by sucrose gradient sedimentation of the DNA. Aerosolization of E. coli in air containing ozonized cyclohexene at 80 percent relative humidity decreased the survival by a factor of 10(3) or more after 1 h of exposure and induced many breaks in the DNA. PMID:341811

  17. BASE COMPOSITION OF THE DEOXYRIBONUCLEIC ACID OF SULFATE-REDUCING BACTERIA.

    Science.gov (United States)

    SIGAL, N; SENEZ, J C; LEGALL, J; SEBALD, M

    1963-06-01

    Sigal, Nicole (Laboratoire de Chimie Bactérienne du CNRS, Marseille, France), Jacques C. Senez, Jean Le Gall, and Madeleine Sebald. Base composition of the deoxyribonucleic acid of sulfate-reducing bacteria. J. Bacteriol. 85:1315-1318. 1963-The deoxyribonucleic acid constitution of several strains of sulfate-reducing bacteria has been analytically determined. The results of these studies show that this group of microorganisms includes at least four subgroups characterized by significantly different values of the adenine plus thymine to guanine plus cytosine ratio. The nonsporulated forms with polar flagellation, containing both cytochrome c(3) and desulfoviridin, are divided into two subgroups. One includes the fresh-water, nonhalophilic strains with base ratio from 0.54 to 0.59, and the other includes the halophilic or halotolerant strains with base ratio from 0.74 to 0.77. The sporulated, peritrichous strains without cytochrome and desulfoviridin ("nigrificans" and "orientis") are distinct from the above two types and differ from each other, having base ratios of 1.20 and 1.43, respectively.

  18. Deoxyribonucleic acid repair in Escherichia coli mutants deficient in the 5'----3' exonuclease activity of deoxyribonucleic acid polymerase I and exonuclease VII

    International Nuclear Information System (INIS)

    Chase, J.W.; Masker, W.E.

    1977-01-01

    A series of Escherichia coli strains deficient in the 5'----3' exonuclease activity associated with deoxyribonucleic acid (DNA) polymerase I (exonuclease VI) and exonuclease VII has been constructed. Both of these enzymes are capable of pyrimidine dimer excision in vitro. These strains were examined for conditional lethality, sensitivity to ultraviolet (UV) and X-irradiation, postirradiation DNA degradation, and ability to excise pyrimidine dimers. It was found that strains deficient in both exonuclease VI (polAex-) and exonuclease VII (xseA-) are significantly reduced in their ability to survive incubation at elevated temperature (43 degrees C) beyond the reduction previously observed for the polAex single mutants. The UV and X-ray sensitivity of the exonuclease VI-deficient strains was not increased by the addition of the xseA7 mutation. Mutants deficient in both enzymes are about as efficient as wild-type strains at excising dimers produced by up to 40 J/m2 UV. At higher doses strains containing only polAex- mutations show reduced ability to excise dimers; however, the interpretation of dimer excision data at these doses is complicated by extreme postirradiation DNA degradation in these strains. The additional deficiency in the polAex xseA7 double-mutant strains has no significant effect on either postirradiation DNA degradation or the apparent deficiency in dimer excision at high UV doses observed in polAex single mutants

  19. Role of deoxyribonucleic acid polymerases and deoxyribonucleic acid ligase in x-ray-induced repair synthesis in toluene-treated Escherichia coli K-12

    International Nuclear Information System (INIS)

    Billen, D.; Hellermann, G.R.

    1976-01-01

    Toluene-treated Escherichia coli mutants have been used to study the roles of deoxyribonucleic acid (DNA) polymerases I, II, and III, and of DNA ligase in repair synthesis and strand rejoining following X-irradiation. In cells possessing all three DNA polymerases, both a greater amount of repair synthesis (''exaggerated'' repair synthesis) and failure of ligation are observed when DNA ligase activity is inhibited. In a mutant lacking the polymerizing activity of DNA polymerase I, exaggerated repair synthesis is not observed, and strand rejoining does not occur even if DNA ligase is fully activated. In a mutant possessing the polymerizing activity of DNA polymerase I but lacking its 5' → 3' exonuclease activity, exaggerated repair synthesis is minimal. After irradiation, DNA polymerases II and III are capable of carrying out an adenosine 5'-triphosphate-dependent repair synthesis, but rejoining of strand breaks does not occur and exaggerated synthesis is not seen whether DNA ligase is active or not. These results suggest that DNA polymerase I and DNA ligase act together to limit repair synthesis after X irradiation and that both are necessary in toluene-treated cells for strand rejoining. DNA polymerases II and III apparently cannot complete chain elongation and gap filling, and therefore repair carried out by these enzymes does not respond to ligase action

  20. Nucleolytic degradation of homologous and heterologous deoxyribonucleic acid molecules at the surface of competent pneumococci

    International Nuclear Information System (INIS)

    Seto, H.; Lopez, R.; Garrigan, O.; Tomasz, A.

    1975-01-01

    Competent pneumococci can catalyze the rapid and quantitative degradation of extracellular deoxyribonucleic acid (DNA) molecules through the activity of surface-located nucleases (endo- and, possibly, exonucleases as well). Both homologous and heterologous DNAs are degraded by a mechanism that seems to involve a cyclic process: (i) attachment of DNA to the cell surface followed by (ii) nucleolytic attack, and (iii) release to the medium. Processes (ii) and (iii) are both inhibited by ethylenediaminetetraacetate. Whereas surface nuclease activity is specific for competent cells, the bulk of this activity is not coupled to irreversible DNA uptake (deoxyribonuclease-resistant binding). Pneumococcal DNA treated with ultraviolet irradiation or nitrous acid (cross-linking) is selectively impaired in the ability to irreversibly bind to competent cells, whereas reversible binding is normal. (U.S.)

  1. Binding of T4 endonuclease V to deoxyribonucleic acid irradiated with ultraviolet light

    International Nuclear Information System (INIS)

    Seawell, P.C.; Simon, T.J.; Ganesan, A.K.

    1980-01-01

    Endonuclease V of bacteriophage T4 binds to uv-irradiated deoxyribonucleic acid (DNA) but not to unirradiated DNA. We have developed an assay to detect this binding, based on the retention of enzyme - DNA complexes on nitrocellulose filters. The amount of complex retained, ascertained by using radioactive DNA, is a measure of T4 endonuclease V activity. From our data we conclude that (1) T4 endonuclease V binds to uv-irradiated DNA but not to DNA that has been previously incised by the endonuclease, (2) equilibrium between the free and complexed form of the enzyme is attained under our reaction conditions, (3) dissociation of enzyme - DNA complexes is retarded by sodium cyanide, and (4) retention of enzyme - DNA complexes on nitrocellulose filters is enhanced by high concentrations of saline-citrate

  2. Tif-stimulated deoxyribonucleic acid repair in Escherichia coli K-12

    International Nuclear Information System (INIS)

    Castellazzi, M.; Jacques, M.; George, J.

    1980-01-01

    Bacterial survival is significantly increased after ultraviolet irradiation in tif sfi cells, provided that the thermosensitive tif mutation has been expressed at 41 0 C before irradiation. This tif-mediated reactivation of ultraviolet irradiated bacteria needs de novo protein synthesis, as is the case for the tif-mediated reactivation of ultraviolet-irradiated phage lambda. However, in striking contrast to the phage reactivation process, this tif-mediated reactivation is no longer associated with mutagenesis. It also requires the presence of the uvrA + excision function. These results strongly suggest the existence in Escherichia coli K-12 of a repair pathway acting on bacterial deoxyribonucleic acid which is inducible, error free, and uvr dependent

  3. Study of the interaction of enzyme Heparanase 1 (HPSE1) active with deoxyribonucleic acids

    International Nuclear Information System (INIS)

    Cid, Gisele da Silva

    2016-01-01

    The human heparanase 1 (HPSE 1) is a protein with multiple functions and has emerged as a promising therapeutic target in the context of antitumor therapy. This fact is due to its clinical relevance in the tumor development and progression, as determined by their enzymatic ability to degrade heparan sulfate (HS), the main constituent of the extracellular matrix, providing a tumor microenvironment to tumor dissemination. In addition, this protein plays a significant role in the increase of tumor cells migration ionizing radiation dose delivery in radiotherapy from the increase in the expression levels of HPSE1. In order to evaluate in more detail the functions of active HPSE1, it has been proposed to characterize the interaction of human heparanase protein 1 with deoxyribonucleic acids. Our results are original and point to a new function of HPSE1 of the endonuclease type. (author)

  4. Integrity of nuclear genomic deoxyribonucleic acid in cooked meat: Implications for food traceability.

    Science.gov (United States)

    Aslan, O; Hamill, R M; Sweeney, T; Reardon, W; Mullen, A M

    2009-01-01

    It is essential to isolate high-quality DNA from muscle tissue for PCR-based applications in traceability of animal origin. We wished to examine the impact of cooking meat to a range of core temperatures on the quality and quantity of subsequently isolated genomic (specifically, nuclear) DNA. Triplicate steak samples were cooked in a water bath (100 degrees C) until their final internal temperature was 75, 80, 85, 90, 95, or 100 degrees C, and DNA was extracted. Deoxyribonucleic acid quantity was significantly reduced in cooked meat samples compared with raw (6.5 vs. 56.6 ng/microL; P 800 bp) were observed only when using DNA from raw meat and steak cooked to lower core temperatures. Small amplicons (food authentication, it is less abundant, and results suggest that analyses should be designed to use small amplicon sizes for meat cooked to high core temperatures.

  5. Dielectric behavior of irradiated and nonirradiadiated deoxyribonucleic acid (DNA)-crotonic acid interaction in 5% dextrose solution

    International Nuclear Information System (INIS)

    Erginun, M.

    1980-01-01

    Deoxyribonucleic acid (DNA), ex. thymus, dissolved in 5% dextrose, was exposed to gamma radiation at doses between 0-5000 Rads. Crotonic acid dissolved in 5% dextrose was added to this irradiated DNA at t=0 and t=24 hrs after irradiation, in concentrations between 0-1.000 mg/ml. The dielectric behavior of the DNA-irradiation-crotonic acid interaction was investigated at T=20 0 C by pH, permittivity (dielectric constant) and conductivity measurements. The pH, permittivity and conductivity measurements exhibit that the effective and critical conditions for the DNA-irradiation-crotonic acid interaction are; low doses of irradiation (350 Rad.), low concentrations of crotonic acid (0.05-0.100 mg/ml) and the addition of crotonic acid 24 hours after the irradiation. These results support and are in good agreement with those results observed with mammalian cells and laboratory animals when the chemical carcinogens are given in conjunction with radiation

  6. Effect of gyrB-mediated changes in chromosome structure on killing of Escherichia coli by ultraviolet light: experiments with strains differing in deoxyribonucleic acid repair capacity

    International Nuclear Information System (INIS)

    von Wright, A.; Bridges, B.A.

    1981-01-01

    Mutations at the gyrB locus were found to decrease the degree of supercoiling of the Escherichia coli chromosome. The effect of a gyrB mutation on the repair of ultraviolet-induced deoxyribonucleic acid damage was studied by following the killing of strains of E. coli K-12 proficient and deficient in deoxyribonucleic acid repair. The effectiveness of both excision and postreplication types of deoxyribonucleic acid repair was found to be altered by this mutation, the former being apparently enhanced and the latter impaired

  7. Optoelectronic studies on heterocyclic bases of deoxyribonucleic acid for DNA photonics.

    Science.gov (United States)

    El-Diasty, Fouad; Abdel-Wahab, Fathy

    2015-10-01

    The optoelectronics study of large molecules, particularly π-stacking molecules, such as DNA is really an extremely difficult task. We perform first electronic structure calculations on the heterocyclic bases of 2'-deoxyribonucleic acid based on Lorentz-Fresnel dispersion theory. In the UV-VIS range of spectrum, many of the optoelectronic parameters for DNA four bases namely adenine, guanine, cytosine and thymine are calculated and discussed. The results demonstrate that adenine has the highest hyperpolarizability, whereas thymine has the lowest hyperpolarizability. Cytosine has the lower average oscillator energy and the higher lattice energy. Thymine infers the most stable nucleic base with the lower phonon energy. Thymine also has the highest average oscillator energy and the lower lattice energy. Moreover, the four nucleic acid bases have large band gap energies less than 5 eV with a semiconducting behavior. Guanine shows the smallest band gap and the highest Fermi level energy, whereas adenine elucidates the highest band gap energy. Copyright © 2015. Published by Elsevier B.V.

  8. Cell division in Escherichia coli BS-12 is hypersensitive to deoxyribonucleic acid damage by ultraviolet light

    International Nuclear Information System (INIS)

    Bridges, B.A.; Mottershead, R.P.; Green, M.H.

    1977-01-01

    Escherichia coli BS-12 uvrA lon is hypersensitive to ultraviolet light. On minimal agar plates at densities in excess of about 10(7) bacteria per plate, as few as one or two photoreversible pyrimidine dimers in the entire genome are sufficient to cause inhibition of cell division. Most of the resulting filaments are unable to divide or form a viable colony. Inhibition of cell division appears to be a rapid consequence of replication of deoxyribonucleic acid containing a pyrimidine dimer. Photoreversibility of the inhibition of cell division persists indefinitely, indicating that the continued presence of the pyrimidine dimers (or the continued generation of daughter strand gaps) is necessary to maintain the division-inhibited state. In view of the kinetics for the production of filamentation by ultraviolet light and the extremely low average inducing fluence (0.03 J/m2), it is concluded that the initiating signal is not the same as that causing other inducible phenomena such as prophage induction or Weigle reactivation

  9. Photoreactions of ruthenium(II) and osmium(II) complexes with deoxyribonucleic acid (DNA).

    Science.gov (United States)

    Moucheron, C; Kirsch-De Mesmaeker, A; Kelly, J M

    1997-09-01

    The design of Ru(II) and Os(II) complexes which are photoreactive with deoxyribonucleic acid (DNA) represents one of the main targets for the development of novel molecular tools for the study of DNA and, in the future, for the production of new, metal-based, anti-tumor drugs. In this review, we explain how it is possible to make a complex photoreactive with nucleobases and nucleic acids. According to the photophysical behaviour of the Ru(II) compounds, two types of photochemistry are expected: (1) photosubstitution of a ligand by a nucleobase and another monodentate ligand, which takes place from the triplet, metal-centred (3MC) state; this state is populated thermally from the lowest lying triplet metal to ligand charge transfer (3MLCT) state; (2) photoreaction from the 3MLCT state, corresponding to photoredox processes with DNA bases. The two photoreactivities are in competition. By modulating appropriately the redox properties of the 3MLCT state, an electron transfer process from the base to the excited complex takes place, and is directly correlated with DNA cleavage or the formation of an adduct of the complex to DNA. In this adduct, guanine is linked by N2 to the alpha-position of a non-chelating nitrogen of the polyazaaromatic ligand without destruction of the complex. Different strategies are explained which increase the affinity of the complexes for DNA and direct the complex photoreactivity to sites of special DNA topology or targeted sequences of bases. Moreover, the replacement of the Ru(II) ion by the Os(II) ion in the photoreactive complexes leads to an increased specificity of photoreaction. Indeed, only one type of photoreactivity (from the 3MLCT state) is present for the Os(II) complexes because the 3MC state is too high in energy to be populated at room temperature.

  10. Electrogenerated chemiluminescence detection for deoxyribonucleic acid hybridization based on gold nanoparticles carrying multiple probes

    International Nuclear Information System (INIS)

    Wang Hui; Zhang Chengxiao; Li Yan; Qi Honglan

    2006-01-01

    A novel sensitive electrogenerated chemiluminescence (ECL) method for the detection deoxyribonucleic acid (DNA) hybridization based on gold nanoparticles carrying multiple probes was developed. Ruthenium bis(2,2'-bipyridine)(2,2'-bipyridine-4,4'-dicarboxylic acid)-N-hydroxysuccinimide ester (Ru(bpy) 2 (dcbpy)NHS) was used as a ECL label and gold nanoparticle as a carrier. Probe single strand DNA (ss-DNA) was self-assembled at the 3'-terminal with a thiol group to the surface of gold nanoparticle and covalently labeled at the 5'-terminal of a phosphate group with Ru(bpy) 2 (dcbpy)NHS and the resulting conjugate (Ru(bpy) 2 (dcbpy)NHS)-ss-DNA-Au, was taken as a ECL probe. When target analyte ss-DNA was immobilized on a gold electrode by self-assembled monolayer technique and then hybridized with the ECL probe to form a double-stranded DNA (ds-DNA), a strong ECL response was electrochemically generated. The ECL intensity was linearly related to the concentration of the complementary sequence (target ss-DNA) in the range from 1.0 x 10 -11 to 1.0 x 10 -8 mol L -1 , and the linear regression equation was S = 57301 + 4579.6 lg C (unit of C is mol L -1 ). A detection limit of 5.0 x 10 -12 mol L -1 for target ss-DNA was achieved. The ECL signal generated from many reporters of ECL probe prepared is greatly amplified, compared to the convention scheme which is based on one reporter per hybridization event

  11. Molecular dynamics simulations of deoxyribonucleic acids and repair enzyme T4 endonuclease V

    International Nuclear Information System (INIS)

    Pinak, Miroslav

    1999-01-01

    This report describes the results of molecular dynamics (MD) simulation of deoxyribonucleic acids (DNA) and specific repair enzyme T4 endonuclease V. Namely research described here is focused on the examination of specific recognition process, in which this repair enzyme recognizes the damaged site on the DNA molecule-thymine dimer (TD). TD is frequent DNA damage induced by UV radiation in sun light and unless properly repaired it may be mutagenic or lethal for cell, and is also considered among the major causes of skin cancer. T4 endonuclease V is a DNA specific repair enzyme from bacteriophage T4 that catalyzes the first reaction step of TD repair pathway. MD simulations of three molecules - native DNA dodecamer (12 base pairs), DNA of the same sequence of nucleotides as native one but with TD, and repair enzyme T4 endonuclease V - were performed for 1 ns individually for each molecule. Simulations were analyzed to determine the role of electrostatic interaction in the recognition process. It is found that electrostatic energies calculated for amino acids of the enzyme have positive values of around +15 kcal/mol. The electrostatic energy of TD site has negative value of approximately -9 kcal/mol, different from the nearly neutral value of the respective thymines site of the native DNA. The electrostatic interaction of TD site with surrounding water environment differs from the electrostatic interaction of other nucleotides. Differences found between TD site and respective thymines site of native DNA indicate that the electrostatic energy is an important factor contributing to proper recognition of TD site during scanning process in which enzyme scans the DNA. In addition to the electrostatic energy, the important factor in recognition process might be structural complementarity of enzyme and bent DNA with TD. There is significant kink formed around TD site, that is not observed in native DNA. (author)

  12. Oxygen-independent direct deoxyribonucleic acid backbone breakage caused by rose bengal and visible light

    Energy Technology Data Exchange (ETDEWEB)

    Peak, M J; Peak, J G; Foote, C S; Krinsky, N I

    1984-01-01

    An oxygen enhancement ratio of 10 for the induction of backbone single-strand breaks (SSBs) in purified deoxyribonucleic acid (DNA) by monochromatic 365 nm UV radiation was obtained. Similarly, a dose reduction factor of 10 was observed when the DNA was irradiated in the presence of 0.1 M diazabicyclo(2.2.2)octane (DABCO). To determine whether this breakage of DNA was due to the action of a reactive oxygen species such as singlet oxygen, we used the photosensitizing dye Rose Bengal and visible light as a system for generating singlet oxygen. Treatment of the DNA with Rose Bengal and 545 nm monochromatic light enhanced the rate of induction of SSBs six times, compared with the rate we obtained when the light was used alone. Elimination of oxygen or addition of 0.1 M DABCO during the 545 nm irradiation in the presence of Rose Bengal did not alter the enhancement of SSBs in the DNA caused by Rose Bengal and 545 nm radiation. The induction of SSBs in the DNA caused by irradiation of the DNA by 545 nm light in the presence of Rose Bengal was not enhanced by the use of D/sub 2/O instead of H/sub 2/O as a solvent. The results indicate that Rose Bengal plus visible light can cause biological damage without the intermediacy of reactive oxygen species, i.e. Rose Bengal and visible light can react directly with biological material, in reactions that appear to be type I photosensitized processes, independent of singlet oxygen as an intermediate.

  13. pH-responsive deoxyribonucleic acid capture/release by polydopamine functionalized magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu; Ma, Xiangdong; Ding, Chun; Jia, Li, E-mail: jiali@scnu.edu.cn

    2015-03-03

    Highlights: • PDA@Fe{sub 3}O{sub 4} were prepared and applied for efficient extraction of DNA from pathogens. • The DNA capture and release by PDA@Fe{sub 3}O{sub 4} was pH-induced. • The adsorption capacity of PDA@Fe{sub 3}O{sub 4} for DNA was 161 mg g{sup −1}. • PDA@Fe{sub 3}O{sub 4} based MSPE was combined with PCR and CE for rapid detection of pathogens. - Abstract: Polydopamine functionalized magnetic nanoparticles (PDA@Fe{sub 3}O{sub 4}) were prepared and characterized by transmission electron microscopy, scanning electron microscopy, zeta potential and vibrating sample magnetometry. They were found to enable highly efficient capture of genomic deoxyribonucleic acid (DNA). The adsorption capacity of PDA@Fe{sub 3}O{sub 4} for genomic DNA can reach 161 mg g{sup −1}. The extraction protocol used aqueous solutions for DNA binding to and releasing from the surface of the magnetic particles based on the pH inducing the charge switch of amino and phenolic hydroxyl groups on PDA@Fe{sub 3}O{sub 4}. The extracted DNA with high quality (A{sub 260}/A{sub 280} = 1.80) can be directly used as templates for polymerase chain reaction (PCR) followed by capillary electrophoresis (CE) analysis. None of the toxic chemical reagents and PCR inhibitors was used throughout the whole procedure. PDA@Fe{sub 3}O{sub 4} based magnetic solid phase extraction (MSPE) method was superior to those using commercial kit and traditional phenol–chloroform extraction methods in yield of DNA. The developed PDA@Fe{sub 3}O{sub 4} based MSPE-PCR-CE method was applied for simultaneous and fast detection of Listeria monocytogenes and Escherichia coli O157:H7 in milk.

  14. A MapReduce approach to diminish imbalance parameters for big deoxyribonucleic acid dataset.

    Science.gov (United States)

    Kamal, Sarwar; Ripon, Shamim Hasnat; Dey, Nilanjan; Ashour, Amira S; Santhi, V

    2016-07-01

    In the age of information superhighway, big data play a significant role in information processing, extractions, retrieving and management. In computational biology, the continuous challenge is to manage the biological data. Data mining techniques are sometimes imperfect for new space and time requirements. Thus, it is critical to process massive amounts of data to retrieve knowledge. The existing software and automated tools to handle big data sets are not sufficient. As a result, an expandable mining technique that enfolds the large storage and processing capability of distributed or parallel processing platforms is essential. In this analysis, a contemporary distributed clustering methodology for imbalance data reduction using k-nearest neighbor (K-NN) classification approach has been introduced. The pivotal objective of this work is to illustrate real training data sets with reduced amount of elements or instances. These reduced amounts of data sets will ensure faster data classification and standard storage management with less sensitivity. However, general data reduction methods cannot manage very big data sets. To minimize these difficulties, a MapReduce-oriented framework is designed using various clusters of automated contents, comprising multiple algorithmic approaches. To test the proposed approach, a real DNA (deoxyribonucleic acid) dataset that consists of 90 million pairs has been used. The proposed model reduces the imbalance data sets from large-scale data sets without loss of its accuracy. The obtained results depict that MapReduce based K-NN classifier provided accurate results for big data of DNA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Identification of a Herbal Powder by Deoxyribonucleic Acid Barcoding and Structural Analyses.

    Science.gov (United States)

    Sheth, Bhavisha P; Thaker, Vrinda S

    2015-10-01

    Authentic identification of plants is essential for exploiting their medicinal properties as well as to stop the adulteration and malpractices with the trade of the same. To identify a herbal powder obtained from a herbalist in the local vicinity of Rajkot, Gujarat, using deoxyribonucleic acid (DNA) barcoding and molecular tools. The DNA was extracted from a herbal powder and selected Cassia species, followed by the polymerase chain reaction (PCR) and sequencing of the rbcL barcode locus. Thereafter the sequences were subjected to National Center for Biotechnology Information (NCBI) basic local alignment search tool (BLAST) analysis, followed by the protein three-dimension structure determination of the rbcL protein from the herbal powder and Cassia species namely Cassia fistula, Cassia tora and Cassia javanica (sequences obtained in the present study), Cassia Roxburghii, and Cassia abbreviata (sequences retrieved from Genbank). Further, the multiple and pairwise structural alignment were carried out in order to identify the herbal powder. The nucleotide sequences obtained from the selected species of Cassia were submitted to Genbank (Accession No. JX141397, JX141405, JX141420). The NCBI BLAST analysis of the rbcL protein from the herbal powder showed an equal sequence similarity (with reference to different parameters like E value, maximum identity, total score, query coverage) to C. javanica and C. roxburghii. In order to solve the ambiguities of the BLAST result, a protein structural approach was implemented. The protein homology models obtained in the present study were submitted to the protein model database (PM0079748-PM0079753). The pairwise structural alignment of the herbal powder (as template) and C. javanica and C. roxburghii (as targets individually) revealed a close similarity of the herbal powder with C. javanica. A strategy as used here, incorporating the integrated use of DNA barcoding and protein structural analyses could be adopted, as a novel

  16. Evaluation of deoxyribonucleic acid (DNA) isolated from human bloodstains exposed to ultraviolet light, heat, humidity, and soil contamination

    International Nuclear Information System (INIS)

    McNally, L.; Shaler, R.C.; Baird, M.; Balazs, I.; De Forest, P.; Kobilinsky, L.

    1989-01-01

    This study was designed to analyze the effects of common environmental insults on the ability to obtain deoxyribonucleic acid (DNA) restriction fragment-length polymorphisms (RFLP) patterns from laboratory prepared specimens. The environmental conditions studied include the exposure of dried bloodstains to varying amounts of relative humidity (0, 33, 67, and 98%), heat (37 degree C), and ultraviolet light for periods of up to five days. In addition, the effect of drying over a four-day period in whole blood collected with and without ethylenediaminetetraacetate (EDTA) was examined. The results of the study showed that, under the conditions studied, the integrity of DNA is not altered such that false RFLP patterns are obtained. The only effect observed was that the overall RFLP pattern becomes weaker, but individual RFLP fragments are neither created nor destroyed

  17. Ability of Bacillus subtilis protoplasts to repair irradiated bacteriophage deoxyribonucleic acid via acquired and natural enzymatic systems

    International Nuclear Information System (INIS)

    Yasbin, R.E.; Andersen, B.J.; Sutherland, B.M.

    1981-01-01

    A novel form of enzyme therapy was achieved by utilizing protoplasts of Bacillus subtilis. Photoreactivating enzyme of Escherichia coli was successfully inserted into the protoplasts of B. subtilis treated with polyethylene glycol. This enzyme was used to photoreactivate ultraviolet-damaged bacteriophage deoxyribonucleic acid (DNA). Furthermore, in polyethylene glycol-treated protoplasts, ultraviolet-irradiated transfecting bacteriophage DNA was shown to be a functional substrate for the host DNA excision repair system. Previous results (R.E. Yasbin, J.D. Fernwalt, and P.I. Fields, J. Bacteriol.; 137: 391-396) showed that ultraviolet-irradiated bacteriophage DNA could not be repaired via the excision repair system of competent cells. Therefore, the processing of bacteriophage DNA by protoplasts and by competent cells must be different. This sensitive protoplast assay can be used to identify and to isolate various types of DNA repair enzymes

  18. Preliminary individualized chemotherapy for malignant astrocytomas based on O6-methylguanine-deoxyribonucleic acid methyltransferase methylation analysis.

    Science.gov (United States)

    Watanabe, Takao; Katayama, Yoichi; Ogino, Akiyoshi; Ohta, Takashi; Yoshino, Atsuo; Fukushima, Takao

    2006-08-01

    O(6)-methylguanine-deoxyribonucleic acid methyltransferase gene (MGMT) methylation is apparently correlated with responsiveness to nitrosourea chemotherapy, suggesting this alkylating agent should be effective against MGMT-methylated tumors. MGMT appears not to be linked to platinum resistance, so platinum chemotherapy should be used for MGMT-unmethylated tumors. This study was a preliminary trial of individualized chemotherapy based on MGMT methylation status in a total of 20 patients with newly diagnosed malignant astrocytomas (9 anaplastic astrocytomas and 11 glioblastomas multiforme). The procarbazine, 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-2(2-chloroethyl)-3-nitrosourea, and vincristine (PAV) regimen was administered to seven patients with MGMT-methylated tumors, and the carboplatin and etoposide (CE) regimen was administered to 13 patients with MGMT-unmethylated tumors. Objective response to the PAV therapy was noted in all three patients with measurable residual tumor (2 complete responses and 1 partial response). Five of the seven patients continued to be disease-free after initiation of the PAV therapy. Objective response to the CE therapy was seen in only one of seven patients with measurable residual tumor (1 partial response). Three of the 13 patients were free from progression, whereas the remaining 10 patients showed early progression. The PAV regimen is effective against MGMT-methylated malignant astrocytomas, but the CE regimen is not useful at the given dose and schedule in MGMT-unmethylated tumors.

  19. Initiation points for cellular deoxyribonucleic acid replication in human lymphoid cells converted by Epstein-Barr virus

    International Nuclear Information System (INIS)

    Oppenheim, A.; Shlomai, Z.; Ben-Bassat, H.

    1981-01-01

    Replicon size was estimated in two Epstein-Barr virus (EBV)-negative human lymphoma lines, BJAB and Ramos, and four EBV-positive lines derived from the former ones by infection (conversion) with two viral strains, B95-8 and P3HR-1. Logarithmic cultures were pulse-labeled with [/sup -3/H]thymidine, and the deoxyribonucleic acid was spread on microscopic slides and autoradiographed by the method of Huberman and Riggs. Three of the four EBV-converted cell lines, BJAB/B95-8, Ra/B95-8, and Ra/HRIK, were found to have significantly shorter replicons (41, 21, 54% shorter, respectively), i.e., more initiation points, than their EBV-negative parents. BJAB/HRIK had replicons which were only slightly shorter (11%) than those of BJAB. However, analysis of track length demonstrated that extensive track fusion occurred during the labeling of BJAB/HRIK, implying that its true average replicon size is shorter than the observed value. The results indicate that in analogy to simian virus 40, EBV activates new initiation points for cellular DNA replication in EBV-transformed cells

  20. The effect of swim-up and gradient sperm preparation techniques on deoxyribonucleic acid (DNA) fragmentation in subfertile patients.

    Science.gov (United States)

    Oguz, Yuksel; Guler, Ismail; Erdem, Ahmet; Mutlu, Mehmet Firat; Gumuslu, Seyhan; Oktem, Mesut; Bozkurt, Nuray; Erdem, Mehmet

    2018-03-23

    To compare the effect of two different sperm preparation techniques, including swim-up and gradient methods on sperm deoxyribonucleic acid (DNA) fragmentation status of semen samples from unexplained and mild male factor subfertile patients undergoing intrauterine insemination (IUI). A prospective randomized study was conducted in 65 subfertile patients, including 34 unexplained and 31 male factor infertility to compare basal and post-procedure DNA fragmentation rates in swim-up and gradient techniques. Sperm DNA fragmentation rates were evaluated by a sperm chromatin dispersion (SCD) test in two portions of each sample of semen that was prepared with either swim-up or gradient techniques. Sperm motility and morphology were also assessed based on WHO 2010 criteria. Swim-up but not gradient method yielded a statistically significant reduction in the DNA fragmented sperm rate after preparation as compared to basal rates, in the semen samples of both unexplained (41.85 ± 22.04 vs. 28.58 ± 21.93, p gradient) and mild male factor (46.61 ± 19.38 vs. 30.32 ± 18.20, p gradient) subgroups. Swim-up method significantly reduces sperm DNA fragmentation rates and may have some prognostic value on intrauterine insemination in patients with decreased sperm DNA integrity.

  1. Deoxyribonucleic Acid Damage and Repair: Capitalizing on Our Understanding of the Mechanisms of Maintaining Genomic Integrity for Therapeutic Purposes

    Directory of Open Access Journals (Sweden)

    Jolene Michelle Helena

    2018-04-01

    Full Text Available Deoxyribonucleic acid (DNA is the self-replicating hereditary material that provides a blueprint which, in collaboration with environmental influences, produces a structural and functional phenotype. As DNA coordinates and directs differentiation, growth, survival, and reproduction, it is responsible for life and the continuation of our species. Genome integrity requires the maintenance of DNA stability for the correct preservation of genetic information. This is facilitated by accurate DNA replication and precise DNA repair. DNA damage may arise from a wide range of both endogenous and exogenous sources but may be repaired through highly specific mechanisms. The most common mechanisms include mismatch, base excision, nucleotide excision, and double-strand DNA (dsDNA break repair. Concurrent with regulation of the cell cycle, these mechanisms are precisely executed to ensure full restoration of damaged DNA. Failure or inaccuracy in DNA repair contributes to genome instability and loss of genetic information which may lead to mutations resulting in disease or loss of life. A detailed understanding of the mechanisms of DNA damage and its repair provides insight into disease pathogeneses and may facilitate diagnosis and the development of targeted therapies.

  2. Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation

    International Nuclear Information System (INIS)

    Bendler, J.W. III

    1976-01-01

    The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 μg/ml, whereas three resistant type b β-lactamase-producing strains could form colonies 1- to 3-μg/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 10 4 -fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence

  3. Solubility of sparingly soluble drug derivatives of anthranilic acid.

    Science.gov (United States)

    Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra

    2011-03-24

    This work is a continuation of our systematic study of the solubility of pharmaceuticals (Pharms). All substances here are derivatives of anthranilic acid, and have an anti-inflammatory direction of action (niflumic acid, flufenamic acid, and diclofenac sodium). The basic thermal properties of pure Pharms, i.e., melting and glass-transition temperatures as well as the enthalpy of melting, have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The equilibrium mole fraction solubilities of three pharmaceuticals were measured in a range of temperatures from 285 to 355 K in three important solvents for Pharm investigations: water, ethanol, and 1-octanol using a dynamic method and spectroscopic UV-vis method. The experimental solubility data have been correlated by means of the commonly known G(E) equation: the NRTL, with the assumption that the systems studied here have revealed simple eutectic mixtures. pK(a) precise measurement values have been investigated with the Bates-Schwarzenbach spectrophotometric method. © 2011 American Chemical Society

  4. Solubilities of boric acid in heavy water

    International Nuclear Information System (INIS)

    Nakai, Shigetsugu; Aoi, Hideki; Hayashi, Ken-ichi; Katoh, Taizo; Watanabe, Takashi.

    1988-01-01

    A gravimetric analysis using meta-boric acid (HBO 2 or DBO 2 ) as a weighing form has been developed for solubility measurement. The method gave satisfactory results in preliminary measurement of solubilities of boric acid in light water. By using this method, the solubilities of 10 B enriched D 3 BO 3 in heavy water were measured. The results are as follows; 2.67 (7deg C), 3.52 (15deg C), 5.70 (30deg C), 8.87 (50deg C) and 12.92 (70deg C) w/o, respectively. These values are about 10% lower than those in light water. Thermodynamical consideration based on the data shows that boric acid is the water structure breaker. (author)

  5. Binding mechanisms for histamine and agmatine ligands in plasmid deoxyribonucleic acid purifications.

    Science.gov (United States)

    Sousa, Ângela; Pereira, Patrícia; Sousa, Fani; Queiroz, João A

    2014-10-31

    Histamine and agmatine amino acid derivatives were immobilized into monolithic disks, in order to combine the specificity and selectivity of the ligand with the high mass transfer and binding capacity offered by monolithic supports, to purify potential plasmid DNA biopharmaceuticals. Different elution strategies were explored by changing the type and salt concentration, as well as the pH, in order to understand the retention pattern of different plasmids isoforms The pVAX1-LacZ supercoiled isoform was isolated from a mixture of pDNA isoforms by using NaCl increasing stepwise gradient and also by ammonium sulfate decreasing stepwise gradient, in both histamine and agmatine monoliths. Acidic pH in the binding buffer mainly strengthened ionic interactions with both ligands in the presence of sodium chloride. Otherwise, for histamine ligand, pH values higher than 7 intensified hydrophobic interactions in the presence of ammonium sulfate. In addition, circular dichroism spectroscopy studies revealed that the binding and elution chromatographic conditions, such as the combination of high ionic strength with extreme pH values can reversibly influence the structural stability of the target nucleic acid. Therefore, ascending sodium chloride gradients with pH manipulation can be preferable chromatographic conditions to be explored in the purification of plasmid DNA biopharmaceuticals, in order to avoid the environmental impact of ammonium sulfate. Copyright © 2014. Published by Elsevier B.V.

  6. Superimposed Code Theoretic Analysis of Deoxyribonucleic Acid (DNA) Codes and DNA Computing

    Science.gov (United States)

    2010-01-01

    DNA strand and its Watson - Crick complement can be used to perform mathematical computation. This research addresses how the...Acid dsDNA double stranded DNA MOSAIC Mobile Stream Processing Cluster PCR Polymerase Chain Reaction RAM Random Access Memory ssDNA single stranded DNA WC Watson – Crick A Adenine C Cytosine G Guanine T Thymine ...are 5′→3′ and strands with strikethrough are 3′→5′. A dsDNA duplex formed between a strand and its reverse complement is called a

  7. In vitro antioxidant potential and deoxyribonucleic acid protecting activity of CNB-001, a novel pyrazole derivative of curcumin

    Directory of Open Access Journals (Sweden)

    Richard L Jayaraj

    2014-01-01

    Full Text Available Background: Free radicals are underpinned to initiate cascade of toxic events leading to oxidative stress and resultant cell death in many neurodegenerative disorders. Now-a-days antioxidants have become mandatory in the treatment of various diseases apart from the drug′s modes of action. CNB-001, a novel hybrid molecule synthesized by combining curcumin and cyclohexyl bisphenol A is known to possess various biological activities, but the antioxidative property of the compound has not yet been elucidated. Aim: The present study is aimed to analyze various free radicals scavenging by employing in vitro antioxidant assays and to evaluate the deoxyribonucleic acid (DNA protecting the ability of CNB-001 against hydroxyl radicals. Materials and methods: The in vitro antioxidant potential of CNB-001 was evaluated by analyzing its ability to scavenge DPPH, ABTS, nitric oxide, superoxide, hydrogen peroxide, superoxide anion, hydroxyl, hydrogen peroxide radicals and reducing power using spectroscopic method. The DNA protecting activity of CNB-001 was also evaluated on pUC19 plasmid DNA subjected to hydroxyl radicals using standard agarose gel electrophoresis. Results: From the assays, it was observed that CNB-001 scavenged free radicals effectively in a dose dependent manner. CNB-001 scavenged 2,2-diphenyl-1-picrylhydrazyl (IC50 = 44.99 μg/ml, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (IC50 = 17.99 μg/ml, nitric oxide (IC50 = 1.36 μg/ml, superoxide radical (IC50 = 77.17 μg/ml, hydrogen peroxide (IC50 = 492.7 μg/ml, superoxide (IC50 = 36.92 μg/ml and hydroxyl (IC50 = 456.5 μg/ml radicals effectively and the reducing power was found to be 11.53 μg/ml. CNB-001 showed considerable protecting activity against plasmid DNA (pUC19 strand scission by ·OH at dose dependent manner. Conclusion: Results from these assays concluded that CNB-001 has a good antioxidant potential by reducing reactive oxygen and reactive nitrogen radicals and it

  8. Interaction with Deoxyribonucleic Acid and Determination of Orientin in Lophatherum gracile Brongn by High-Performance Liquid Chromatography with Amperometric Detection

    International Nuclear Information System (INIS)

    Wang, Fang; Yan, Fangfang; Long, Yuling; Wang, Lili; Chen, Zilin

    2015-01-01

    The mechanisms of the electrochemical oxidation of orientin and its interaction with deoxyribonucleic acid have been investigated using glassy carbon electrode. The electrochemical response of orientin is due to oxidation of phenolic hydroxyl groups on orientin. The whole process is controlled by the adsorption step and concerned 4 electrons and 4 protons. Negative shift of potential and decrease of peak current for electrochemical oxidation of orientin can be observed at bare glassy carbon electrode and deoxyribonucleic acid modified electrode in 0.05 M Na_2HPO_4-KH_2PO_4 (pH 7.48), confirming the dominant electrostatic interaction between orientin and deoxyribonucleic acid. Moreover, a reliable and sensitive method of reversed-phase high-performance liquid chromatography-electrochemical detection has been developed for simultaneous determination of the isomer pair orientin/isoorientin. Chromatographic separation was carried out on a reversed-phase C_1_8 column and a mobile phase comprised of acetonitrile and acetate (0.5%, pH 2.97) by amperometric detection with a glassy carbon electrode at the working potential of +1.00 V. The method was validated for linearity, accuracy, precision, and limit of detection. Under the optimized conditions, linear regression analysis for the calibration curve showed a good linear relationship between peak area and their concentrations in the linear range of 89.2 nM to 59.5 μM for orientin with detection limit of 14.9 nM and 78.0 nM to 52.0 μM for isoorientin with a detection limit of 13.0 nM, respectively. Compared to the method using ultraviolet detection, the detection limits are greatly lowered. Finally, the proposed method has been successfully applied to the determination of orientin and isoorientin in Lophatherum gracile Brongn.

  9. No activation of new initiation points for deoxyribonucleic acid replication in BALB/c 3T3 cells transformed by Kirsten sarcoma virus

    International Nuclear Information System (INIS)

    Oppenheim, A.; Horowitz, A.T.

    1981-01-01

    BALB/c 3T3 cells were transformed by Kirsten sarcoma virus, and five clones were isolated in soft agar. Average replicon sizes of the transformed cell lines were stimated by the method of fiber-autoradiography and found to be the same size as the nontransformed 3T3 cells, analyzed in parallel. The results indicate that, unlike simian virus 40 and Epstein-Barr virus, Kirsten sarcoma virus does not activate new initiation points for cellular deoxyribonucleic acid replication in murine sarcome virus-transformed BALB/c 3T3 cells

  10. Modification and restriction of T-even bacteriophages. In vitro degradation of deoxyribonucleic acid containing 5-hydroxymethylctosine.

    Science.gov (United States)

    Fleischman, R A; Cambell, J L; Richardson, C C

    1976-03-25

    Using the single-stranded circular DNA of bacteriophage fd as template, double-stranded circular DNA has been prepared in vitro with either 5-hydroxymethylcytosine ([hmdC]DNA) or cytosine ([dC]DNA) in the product strand. Extracts prepared from Escherichia coli cells restrictive to T-even phage containing nonglucosylated DNA degrade [hmdC]DNA to acid-soluble material in vitro, but do not degrade [dC]dna. In contrast, extracts prepared from E. coli K12 rglA- rglB-, a strain permissive to T-even phage containing nonglucosylated DNA, do not degrade [hmdC]DNA or [dC]DNA. In addition, glucosylation of the [hmdC]DNA renders it resistant to degradation by extracts from restrictive strains. The conversion of [hmdC]DNA to acid-soluble material in vitro consists of an HmCyt-specific endonucleolytic cleavage requiring the presence of the RglB gene product to form a linear molecule, followed by a non-HmCyt-specific hydrolysis of the linear DNA to acid-soluble fragments, catalyzed in part by exonuclease V. The RglB protein present in extracts of E. coli K12 rglA- rglB+ has been purified 200-fold by complementation with extracts from E. coli K12 rglA- rglB-. The purified RglB protein does not contain detectable HmCyt-specific endonuclease or exonuclease activity. In vitro endonucleolytic cleavage of [hmdC]DNA thus requires additional factors present in cell extracts.

  11. Anomalous Solubility Behavior of Several Acidic Drugs

    Directory of Open Access Journals (Sweden)

    Alex Avdeef

    2014-04-01

    Full Text Available The “anomalous solubility behavior at higher pH values” of several acidic drugs originally studied by Higuchi et al. in 1953 [1], but hitherto not fully rationalized, has been re-analyzed using a novel solubility-pH analysis computer program, pDISOL-XTM. The program internally derives implicit solubility equations, given a set of proposed equilibria and constants (iteratively refined by weighted nonlinear regression, and does not require explicit Henderson-Hasselbalch equations. The re-analyzed original barbital, phenobarbital, oxytetracycline, and sulfathiazole solubility-pH data of Higuchi et al. is consistent with the presence of dimers in saturated solutions. In the case of barbital, phenobarbital and sulfathiazole, anionic dimers, reaching peak concentrations near pH 8. However, oxytetracycline indicated a pronounced tendency to form a cationic dimer, peaking near pH 2. Under the conditions of the original study, only barbital indicated a slight tendency to form a salt precipitate at pH > 6.8, with a highly unusual stoichiometry (consistent with a slope of 0.55 in the log S – pH plot: K+ + A2H- + 3HA D KA5H4(s. Thus the “anomaly” in the Higuchi data can be rationalized by invoking specific aggregated species.

  12. Effects of 5 Thio-D-Glucose on cellular adenosine triphosphate levels and deoxyribonucleic acid rejoining in hypoxic and aerobic Chinese hamster cells

    International Nuclear Information System (INIS)

    Nagle, W.A.; Moss, A.J. Jr.; Roberts, H.G. Jr.; Baker, M.L.

    1980-01-01

    Intracellular adenosine triphosphate (ATP) levels were measured in both hypoxic and aerobic cultures of V79 Chinese hamster cells treated with 5-thio-D-glucose (5-SH-D-Glc). This glucose analog, a known inhibitor of D-glucose transport and metabolism, reduced ATP in cell cultures allowed to become hypoxic by cell metabolism, but not in aerobic cultures treated similarly. Cells depleted of ATP were unable to rejoin x-ray induced deoxyribonucleic acid (DNA) strand breaks as measured by the alkaline sucrose gradient sedimentation technique. The inference for radiation therapy is that inhibition of glucose metabolism selectively depletes energy reserves in hypoxic cells, rendering these cells more radiosensitive and leading to a more effective tumor treatment

  13. Study of the interaction of enzyme Heparanase 1 (HPSE1) active with deoxyribonucleic acids; Estudo de interacao da enzima Heparanase 1 (HPSE 1) ativa com acido desoxirribonucleicos

    Energy Technology Data Exchange (ETDEWEB)

    Cid, Gisele da Silva

    2016-07-01

    The human heparanase 1 (HPSE 1) is a protein with multiple functions and has emerged as a promising therapeutic target in the context of antitumor therapy. This fact is due to its clinical relevance in the tumor development and progression, as determined by their enzymatic ability to degrade heparan sulfate (HS), the main constituent of the extracellular matrix, providing a tumor microenvironment to tumor dissemination. In addition, this protein plays a significant role in the increase of tumor cells migration ionizing radiation dose delivery in radiotherapy from the increase in the expression levels of HPSE1. In order to evaluate in more detail the functions of active HPSE1, it has been proposed to characterize the interaction of human heparanase protein 1 with deoxyribonucleic acids. Our results are original and point to a new function of HPSE1 of the endonuclease type. (author)

  14. Evaluation of Deoxyribonucleic Acid Toxicity Induced by the Radiopharmaceutical 99mTechnetium-Methylenediphosphonic Acid and by Stannous Chloride in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Adriano Caldeira-de-Araujo

    2012-11-01

    Full Text Available Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends on a reducing agent, stannous chloride (SnCl2 being the most widely-utilized. The genotoxic, clastogenic and anegenic properties of the 99mTc-MDP(methylene diphosphonate used for bone SPECT and SnCl2 were evaluated in Wistar rat blood cells using the Comet assay and micronucleus test. The experimental approach was to endovenously administer NaCl 0.9% (negative control, cyclophosphamide 50 mg/kg b.w. (positive control, SnCl2 500 μg/mL or 99mTc-MDP to animals and blood samples taken immediately before the injection, 3, and 24 h after (in the Comet assay and 36 h after, for micronucleus test. The data showed that both SnCl2 and 99mTc-MDP-induced deoxyribonucleic acid (DNA strand breaks in rat total blood cells, suggesting genotoxic potential. The 99mTc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. Taken together, the data presented here points to the formation of a complex between SnCl2 in the radiopharmaceutical 99mTc-MDP, responsible for the decrease in cell damage, compared to both isolated chemical agents. These findings are important for the practice of nuclear medicine.

  15. Solubility of xenon in amino-acid solutions. II. Nine less-soluble amino acids

    Science.gov (United States)

    Kennan, Richard P.; Himm, Jeffrey F.; Pollack, Gerald L.

    1988-05-01

    Ostwald solubility (L) of xenon gas, as the radioisotope 133Xe, has been measured as a function of solute concentration, at 25.0 °C, in aqueous solutions of nine amino acids. The amino-acid concentrations investigated covered much of their solubility ranges in water, viz., asparagine monohydrate (0-0.19 M), cysteine (0-1.16 M), glutamine (0-0.22 M), histidine (0-0.26 M), isoleucine (0-0.19 M), methionine (0-0.22 M), serine (0-0.38 M), threonine (0-1.4 M), and valine (0-0.34 M). We have previously reported solubility results for aqueous solutions of six other, generally more soluble, amino acids (alanine, arginine, glycine, hydroxyproline, lysine, and proline), of sucrose and sodium chloride. In general, L decreases approximately linearly with increasing solute concentration in these solutions. If we postulate that the observed decreases in gas solubility are due to hydration, the results under some assumptions can be used to calculate hydration numbers (H), i.e., the number of H2O molecules associated with each amino-acid solute molecule. The average values of hydration number (H¯) obtained at 25.0 °C are 15.3±1.5 for asparagine, 6.8±0.3 for cysteine, 11.5±1.1 for glutamine, 7.3±0.7 for histidine, 5.9±0.4 for isoleucine, 10.6±0.8 for methionine, 11.2±1.3 for serine, 7.7± 1.0 for threonine, and 6.6±0.6 for valine. We have also measured the temperature dependence of solubility L(T) from 5-40 °C for arginine, glycine, and proline, and obtained hydration numbers H¯(T) in this range. Between 25-40 °C, arginine has an H¯ near zero. This may be evidence for an attractive interaction between xenon and arginine molecules in aqueous solution.

  16. The solubilities of benzene polycarboxylic acids in water

    International Nuclear Information System (INIS)

    Apelblat, Alexander; Manzurola, Emanuel; Abo Balal, Nazmia

    2006-01-01

    The solubilities in water of all benzene polycarboxylic acids are discussed, using data determined in this work (benzoic, terephthalic, trimellitic, trimesic, and pyromellitic acids) and available from the literature (benzoic, phthalic, isophthalic, terephthalic, hemimellitic, trimelitic, trimesic, mellophanic, prehnitic, pyromellitic, benzene-pentacarboxylic and mellitic acids). The apparent molar enthalpies of solution at the saturation point for these benzene polycarboxylic acids were determined from the temperature dependence of the solubilities

  17. Solubility of cefoxitin acid in different solvent systems

    International Nuclear Information System (INIS)

    Yuan, Fuhong; Wang, Yongli; Xiao, Liping; Huang, Qiaoyin; Xu, Jinchao; Jiang, Chen; Hao, Hongxun

    2016-01-01

    Highlights: • The solubility of cefoxitin acid in different solvent systems was measured. • Three models were used to correlate the solubility data. • The dissolution enthalpy of the dissolution process was calculated. - Abstract: Cefoxitin acid is one kind of important pharmaceutical intermediate. Its solubility is crucial for designing and optimizing the crystallization processes. In this work, the solubility of cefoxitin acid in organic solvents (methanol, acetonitrile, ethanol, isopropanol, n-propanol and ethyl acetate), water and water-methanol mixtures was measured spectrophotometrically using a shake-flask method within the temperature range 278.15–303.15 K. PXRD data and the Karl Fischer method were used to verify the crystal form stability of cefoxitin acid in the solubility measuring process. The melting points, the enthalpy and entropy of fusion were estimated. Results showed that the solubility of cefoxitin acid increases with the increasing temperature in all tested solvents in this work, and the solubility of cefoxitin acid increases with the increasing methanol concentration in water-methanol mixtures. The experimental solubility values were well correlated using the modified Apelblat equation, NRTL model and CNIBS/R-K model. An equation proposed by Williamson was adopted to calculate the molar enthalpy during the dissolution process.

  18. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with atmospheric ... molecular weight carboxylic acids in aerosol samples collected from a rural ... include biomass burning, agriculture, livestock and soil dust. Tropical ...

  19. An unusual mode of DNA duplex association: Watson-Crick interaction of all-purine deoxyribonucleic acids.

    Science.gov (United States)

    Battersby, Thomas R; Albalos, Maria; Friesenhahn, Michel J

    2007-05-01

    Nucleic acid duplexes associating through purine-purine base pairing have been constructed and characterized in a remarkable demonstration of nucleic acids with mixed sequence and a natural backbone in an alternative duplex structure. The antiparallel deoxyribose all-purine duplexes associate specifically through Watson-Crick pairing, violating the nucleobase size-complementarity pairing convention found in Nature. Sequence-specific recognition displayed by these structures makes the duplexes suitable, in principle, for information storage and replication fundamental to molecular evolution in all living organisms. All-purine duplexes can be formed through association of purines found in natural ribonucleosides. Key to the formation of these duplexes is the N(3)-H tautomer of isoguanine, preferred in the duplex, but not in aqueous solution. The duplexes have relevance to evolution of the modern genetic code and can be used for molecular recognition of natural nucleic acids.

  20. Ionizing radiation damage to the folded chromosome of Escherichia coli K-12: repair of double-strand breaks in deoxyribonucleic acid

    International Nuclear Information System (INIS)

    Ulmer, M.K.; Gomez, R.F.; Sinskevy, A.J.

    1979-01-01

    The extremely gentle lysis and unfolding procedures that have been developed for the isolation of nucleoid deoxyribonucleic acid yield undamaged, replicating genomes, thus permitting direct measurement of the formation and repair of DNA double-strand breaks at biologically significant doses of ionizing radiation. Repair of ionizing radiation damage to folded chromosomes of Escherichia coli K-12 strain AB2497 was observed within 2 to 3 h of post-irradiation incubation in growth medium. Such behavior was not observed after post-irradiation incubation in growth medium of a recA13 strain (strain AB2487). A model based on recombinational repair is proposed to explain the formation of 2,200 to 2,300S material during early stages of incubation and to explain subsequent changes in the gradient profiles. Association of unrepaired DNA with the plasma membrane is proposed to explain the formation of a peak of rapidly sedimenting material (greater than 3,100S) during the later stage of repair. Direct evidence of repair of double-strand breaks during post-irradiation incubation in growth medium was obtained from gradient profiles of DNA from ribonuclease-digested chromosomes. The sedimentation coefficient of broken molecules was restored to the value of unirradiated DNA after 2 to 3 h of incubation, and the fraction of the DNA repaired in this fashion was equal to the fraction of cells that survived at the same dose. An average of 2.7 double-strand breaks per genome per lethal event was observed, suggesting that one to two double-strand breaks per genome are repairable in E. coli K-12 strain AB2497

  1. Comparison of the Rate and Extent of Deoxyribonucleic Acid Repair and Semi-Conservative Synthesis in Bacteria Exposed to Ultra-Violet Light

    Energy Technology Data Exchange (ETDEWEB)

    Billen, D. [Radiation Biology Laboratory and Departments of Microbiology and Radiology, College of Medicine, University of Florida, Gainesville, FL (United States)

    1968-08-15

    Many bacterial strains possess the ability to repair genetic damage resulting from ultra-violet light (u.v. ) exposure. Of major importance is the occurrence of a 'repair' type of deoxyribonucleic acid (DNA) replication during 'dark repair', which presumably results in the replacement of the damaged portion of the genome. With deuterium, {sup 15}N and {sup 13}C as a density label, and buoyant density centrifugation in CsCl as a means of separating pre and post-irradiation synthesized DNA strands, the rate and extent of DNA repair synthesis in exponential - phase Escherichia coli strain B/r were determined. After u.v. exposure, {sup 3}H-thymine incorporation into the 'heavy' parental DNA strands was used to measure repair synthesis, while {sup 3}H-thymine incorporation into 'light' and newly synthesized DNA strands measured semi-conservative replication. The rate of bases incorporated by repair synthesis in the initial 15 minures of post-irradiation incubation at 37 Degree-Sign C appears to be saturated at a dose of approximately 100 ergs/mm{sup 2}. At higher doses (up to 600 ergs/mm{sup 2}) the increase observed was not proportional to dose. During this initial 15 minutes, less than 1% of the chromosomal DNA was replaced. The amount of DNA synthesized by semi-conservative replication during the initial 15 minutes was reduced with increasing u.v. dose. After exposure to 600 ergs/mm{sup 2}, repair and semiconservative DNA synthesis were nearly equivalent in the irradiated cells after 15 minutes of incubation. Repair synthesis was observed to be terminated by 45 minutes in bacteria exposed to 160 or 500 ergs/mm{sup 2} (64% and 10% survivors, respectively). The amount of genome replaced by repair synthesis at several doses was determined. Starvation for a required amino acid (resulting in an inhibition of protein and ribonucleic acid synthesis) did not prevent the repair synthesis nor grossly alter its extent. The restoration of the semi-conservative mo d e of DNA

  2. LITERATURE REVIEW OF BORIC ACID SOLUBILITY DATA

    Energy Technology Data Exchange (ETDEWEB)

    Crapse, K.; Kyser, E.

    2011-09-22

    A new solvent system is being evaluated for use in the Modular Caustic-Side Solvent Extraction Unit (MCU) and in the Salt Waste Processing Facility (SWPF). The new system replaces the current dilute nitric acid strip solution with 0.01 M boric acid. This literature study is performed to determine if there is a potential for boric acid to crystallize in the lines with emphasis on the transfer lines to the Defense Waste Processing Facility. This report focuses on the aqueous phase chemistry of boric acid under conditions relevant to MCU and SWPF. Operating and transfer conditions examined for the purpose of this review include temperatures between 13 C (McLeskey, 2008) and 45 C (Fondeur, 2007) and concentrations from 0 to 3M in nitric acid as well as exposure of small amounts of entrained boric acid in the organic phase to the sodium hydroxide caustic wash stream. Experiments were also conducted to observe any chemical reactions and off-gas generation that could occur when 0.01 M boric acid solution mixes with 3 M nitric acid solution and vice versa. Based on the low concentration (0.01M) of boric acid in the MCU/SWPF strip acid and the moderate operating temperatures (13 C to 45 C), it is unlikely that crystallization of boric acid will occur in the acid strip solution under process or transfer conditions. Mixing experiments of boric and nitric acid show no measurable gas generation (< 1 cc of gas per liter of solution) under similar process conditions.

  3. The acid solubility test of clay mineral under microwave

    International Nuclear Information System (INIS)

    Zheng Ying; Niu Yuqing; Wu Peisheng; Niu Xuejun

    2001-01-01

    The acid solubility test of Al 3+ in clay from some uranium ores under microwave is introduced. The result shows that the concentration of Al 3+ in solution and the acid consumption increase rapidly under microwave comparing with normal leaching condition. It is infeasible to adopt microwave slacking method for intensively leaching uranium from uranium ore containing more clay

  4. 11beta-hydroxysteroid dehydrogenase complementary deoxyribonucleic acid in rainbow trout: cloning, sites of expression, and seasonal changes in gonads.

    Science.gov (United States)

    Kusakabe, Makoto; Nakamura, Ikumi; Young, Graham

    2003-06-01

    11beta-Hydroxysteroid dehydrogenases (11beta-HSDs) are important steroidogenic enzymes for catalyzing the interconversion of active glucocorticoid (cortisol and corticosterone) and inert 11-keto forms (cortisone and 11-dehydrocorticosterone) in mammals. In teleosts, 11beta-HSD also plays a role in the production of the predominant androgen, 11-ketotestosterone, in male fish. In this study we cloned cDNAs encoding rainbow trout 11beta-HSD (rt11beta-HSD) from testes and head kidney. The predicted amino acid sequence, hydrophobicity analysis, and transient transfection assays with rt11beta-HSD in HEK293 cells showed that rt11beta-HSD is a homolog of mammalian 11beta-HSD type 2. rt11beta-HSD transcripts are present in steroidogenic tissues and in a number of other tissues. Strong in situ hybridization signals for rt11beta-HSD transcripts were found in Leydig cells of testes, in thecal cells of the early vitellogenic ovarian follicles, and in thecal and granulosa cells of the midvitellogenic and postovulatory follicles. Weaker signals were also found in head kidney interrenal cells from juvenile rainbow trout. Seasonal changes in rt11beta-HSD transcripts in testes showed a pattern similar to that of stress-induced serum cortisol levels, but not to serum androgen levels. High levels of rt11beta-HSD transcripts were found in ovarian follicles from late vitellogenesis through ovulation. These results raise the possibility of a role for rt11beta-HSD in the protection of developing gonads from the inhibitory effects of stress-induced cortisol.

  5. On the solubility of nicotinic acid and isonicotinic acid in water and organic solvents

    International Nuclear Information System (INIS)

    Abraham, Michael H.; Acree, William E.

    2013-01-01

    Highlights: ► Solubilities of nicotinic acid and isonicotinic acids in organicsolvents have been determined. ► Solubilities are used to calculate Abraham descriptors for the two acids. ► These descriptors then yield water-solvent and gas-solvent partitions into numerous solvents. ► The solubility of the neutral acids in water is obtained. ► The method is straightforward and can be applied to any set of compound solubilities. -- Abstract: We have determined the solubility of nicotinic acid in four solvents and the solubility of isonicotinic acid in another four solvents. These results, together with literature data on the solubility of nicotinic acid in five other organic solvents and isonicotinic acid in four other organic solvents, have been analyzed through two linear Gibbs energy relationships in order to extract compound properties, or descriptors, that encode various solute–solvent interactions. The descriptors for nicotinic acid and isonicotinic acid can then be used in known equations for partition of solutes between water and organic solvents to predict partition coefficients and then further solubility in a host of organic solvents, as well as to predict a number of other physicochemical properties

  6. Analysis of ribo- and deoxyribonucleic acids using ionpair-reversed-phase liquid-chromatography electrospray-mass spectrometry

    International Nuclear Information System (INIS)

    Hoelzl, G.

    2002-10-01

    The fast progress in natural sciences like biology, biochemistry, medicine or genetics make high demands on the analytical chemistry. The on-line coupling of ionpair-reversed phase-liquid chromatography (IP-RP-HPLC) to mass spectrometry (MS) becomes more and more the method of choice for the analysis of biomolecules. The success is based on the introduction of soft ionization methods, like electrospray ionization (ESI), which allows the transfer of intact biopolymers into the gasphase. This combination enables the on-line separation of complex biological mixtures with additional identification of the compounds by their molecular mass. The first part describes the development of a new ionsource, which combines the advantages of a micro-ESI- and a nanospray-source. In combination with additional optimization of the chromatographic conditions the new ionsource showed an improvement of the quality of the spectra by a factor of 5 and a stability of the ionspray by a factor of 2, which resulted in an overall improvement of sensitivity by a factor of 10 for the HPLC-MS system. The second part describes the quality control of synthetic RNA molecules. Using IP-RP-HPLC-ESI-MS it was possible to separate failure sequences and derivatives in raw products of short synthetic RNAs. The derivatives were formed of protecting groups, which were not removed during the deprotection step. The analysis of coupling products of the synthesis of aminoacylated transfer RNAs showed a derivative, which was formed by the addition of the used coupling reagent N-(3-dimethylaminopropyl)N'-ethylcarbodiimide (EDC). The identification of the derivatives led to the optimization of the reaction conditions which resulted in the synthesis of the wanted transfer RNA without any additional derivatives. Another experiment involved the fragmentation of RNA molecules. Tandem mass spectrometry provides the opportunity to determine the sequence of nucleic acids. Fragmentation experiments showed different

  7. Boric acid solubility in the presence of alkali metal nitrides

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, V G; Tsekhanskij, R S; Molodkin, A K; Sadetdinov, Sh V [Chuvashskij Gosudarstvennyj Univ., Cheboksary (USSR); Universitet Druzhby Narodov, Moscow (USSR))

    1983-01-01

    Methods of solubility and refractometry at 25 deg C have been applied to state that systems boric acid-lithium (sodium, potassium) nitrite-water are simple eutonic type systems. Nitrites salt in the acid and their lyotropic effect increases from lithium salt to potassium salt. The disclosed succession in change of the effect is determined by the character of cation hydration in the medium the acidic reaction of which is conditioned by boric acid polymerization and partial oxidation of nitrite ion into nitrate ion. Boric acid is salted out from solutions containing lithium and sodium cations with increase of nitrate ion.

  8. Boric acid solubility in the presence of alkali metal nitrides

    International Nuclear Information System (INIS)

    Skvortsov, V.G.; Tsekhanskij, R.S.; Molodkin, A.K.; Sadetdinov, Sh.V.

    1983-01-01

    Methods of solubility and refractometry at 25 deg C have been applied to state that systems boric acid-lithium (sodiUm, potassium) nitrite-water are simple eutonic type systems. Nitrites salt in the acid and their lyotropic effect increases from lithium salt to potassium salt. The disclosed succession in change of the effect is determined by the character of cation hydration in the medium the acidic reaction of which is conditioned by boric acid polymerization and partial oxidation of nitrite ion into nitrate ion Boric acid is salted out form solutions containing lithium and sodium cations with increase of nitrate ion

  9. A Soluble, Folded Protein without Charged Amino Acid Residues

    DEFF Research Database (Denmark)

    Højgaard, Casper; Kofoed, Christian; Espersen, Roall

    2016-01-01

    Charges are considered an integral part of protein structure and function, enhancing solubility and providing specificity in molecular interactions. We wished to investigate whether charged amino acids are indeed required for protein biogenesis and whether a protein completely free of titratable...... side chains can maintain solubility, stability, and function. As a model, we used a cellulose-binding domain from Cellulomonas fimi, which, among proteins of more than 100 amino acids, presently is the least charged in the Protein Data Bank, with a total of only four titratable residues. We find...

  10. Fluorescence quenching of graphene oxide combined with the site-specific cleavage of restriction endonuclease for deoxyribonucleic acid demethylase activity assay

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Lijuan; Qian, Yingdan; Wu, Ping; Zhang, Hui; Cai, Chenxin, E-mail: cxcai@njnu.edu.cn

    2015-04-15

    Highlights: • An approach for sensitive and selective DNA demethylase activity assay is reported. • This assay is based on the fluorescence quenching of GO and site-specific cleavage of endonuclease. • It can determine as low as 0.05 ng mL{sup −1} of MBD2 with a linear range of 0.2–300 ng mL{sup −1}. • It has an ability to recognize MBD2 from other possibly coexisting proteins and cancer cell extracts. • It can avoid false signals, requiring no bisulfite conversion, PCR amplification, radioisotope-labeling. - Abstract: We report on the development of a sensitive and selective deoxyribonucleic acid (DNA) demethylase (using MBD2 as an example) activity assay by coupling the fluorescence quenching of graphene oxide (GO) with the site-specific cleavage of HpaII endonuclease to improve the selectivity. This approach was developed by designing a single-stranded probe (P1) that carries a binding region to facilitate the interaction with GO, which induces fluorescence quenching of the labeled fluorophore (FAM, 6-carboxyfluorescein), and a sensing region, which contains a hemi-methylated site of 5′-CmCGG-3′, to specifically recognize the target (T1, a 32-mer DNA from the promoter region of p53 gene) and hybridize with it to form a P1/T1 duplex. After demethylation with MBD2, the duplex can be specifically cleaved using HpaII, which releases the labeled FAM from the GO surface and results in the recovery of fluorescence. However, this cleavage is blocked by the hemi-methylation of this site. Thus, the magnitude of the recovered fluorescence signal is related to the MBD2 activity, which establishes the basis of the DNA demethylase activity assay. This assay can determine as low as ∼(0.05 ± 0.01) ng mL{sup −1} (at a signal/noise of 3) of MBD2 with a linear range of 0.2–300 ng mL{sup −1} and recognize MBD2 from other possibly coexisting proteins and cancer cell extracts. The advantage of this assay is its ability to avoid false signals and no

  11. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    Atmospheric aerosol samples of PM2.5 and PM10 were collected in April–May 2011 from a rural site in Tanzania and analyzed for water-soluble inorganic ions and low molecular weight carboxylic acids using ion chromatography. PM2.5 and PM10 low-volume samplers with quartz fibre filters were deployed and aerosol ...

  12. Solubility of salicylic acid in pure alcohols at different temperatures

    International Nuclear Information System (INIS)

    Lim, Junhyuk; Jang, Sunghyun; Cho, Hye Kyoung; Shin, Moon Sam; Kim, Hwayong

    2013-01-01

    Highlights: ► Solubility data of salicylic acid in pure alkanols were measured. ► The experimental data were correlated with NRTL, UNIQUAC and Wilson models. ► The data are fit well with all three models for the six pure alcohols studied. ► Adjustable interaction parameters were suggested. - Abstract: This work focused on the experimental measurements and the numerical calculations of the solubility of salicylic acid in various alcohols. The solubility of salicylic acid in pure alcohols was determined using a (solid + liquid) equilibrium measurement apparatus at temperatures ranging from (278.15 to 318.15) K. Also, the melting temperature and fusion enthalpy of salicylic acid were determined by a differential scanning calorimeter (TA instrument Q100). The experimental results were correlated with the equation for solubility of a solid in a liquid with the nonrandom two liquid (NRTL), universal quasi-chemical (UNIQUAC) and Wilson models for liquid phase activity coefficients to validate the quality of the data taken. Adjustable interaction parameters were also provided. The experimental data fit appropriately with all three models for the pure alcohols studied.

  13. Enhancement of carvedilol solubility by solid dispersion technique using cyclodextrins, water soluble polymers and hydroxyl acid.

    Science.gov (United States)

    Yuvaraja, K; Khanam, Jasmina

    2014-08-05

    Aim of the present work is to enhance aqueous solubility of carvedilol (CV) by solid dispersion technique using wide variety of carriers such as: β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD), tartaric acid (TA), polyvinyl pyrrolidone K-30 (PVP K-30) and poloxamer-407 (PLX-407). Various products of 'CV-solid dispersion' had been studied extensively in various pH conditions to check enhancement of solubility and dissolution characteristics of carvedilol. Any physical change upon interaction between CV and carriers was confirmed by instrumental analysis: XRD, DSC, FTIR and SEM. Negative change of Gibb's free energy and complexation constants (Kc, 75-240M(-1), for cyclodextrins and 1111-20,365M(-1), for PVP K-30 and PLX-407) were the evidence of stable nature of the binding between CV and carriers. 'Solubility enhancement factor' of ionized-CV was found high enough (340 times) with HPβCD in presence of TA. TA increases the binding efficiency of cyclodextrin and changing the pH of microenvironment in dissolution medium. In addition, ionization process was used to increase the apparent intrinsic solubility of drug. In vitro, dissolution time of CV was remarkably reduced in the solid dispersion system compared to that of pure drug. This may be attributed to increased wettability, dispersing ability and transformation of crystalline state of drug to amorphous one. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A Soluble, Folded Protein without Charged Amino Acid Residues

    DEFF Research Database (Denmark)

    Højgaard, Casper; Kofoed, Christian; Espersen, Roall

    2016-01-01

    side chains can maintain solubility, stability, and function. As a model, we used a cellulose-binding domain from Cellulomonas fimi, which, among proteins of more than 100 amino acids, presently is the least charged in the Protein Data Bank, with a total of only four titratable residues. We find......Charges are considered an integral part of protein structure and function, enhancing solubility and providing specificity in molecular interactions. We wished to investigate whether charged amino acids are indeed required for protein biogenesis and whether a protein completely free of titratable...... that the protein shows a surprising resilience toward extremes of pH, demonstrating stability and function (cellulose binding) in the pH range from 2 to 11. To ask whether the four charged residues present were required for these properties of this protein, we altered them to nontitratable ones. Remarkably...

  15. First improvements in the detection and quantification of label-free nucleic acids by laser-induced breakdown spectroscopy: Application to the deoxyribonucleic acid micro-array technology

    International Nuclear Information System (INIS)

    Le Meur, Julien; Menut, Denis; Wodling, Pascal; Salmon, Laurent; Thro, Pierre-Yves; Chevillard, Sylvie; Ugolin, Nicolas

    2008-01-01

    The accurate quantification of nucleic acids is essential in many fields of modern biology and industry, and in some cases requires the use of fluorescence labeling. Yet, in addition to standardization problems and quantification reproducibility, labeling can modify the physicochemical properties of molecules or affect their stability. To address these limitations, we have developed a novel method to detect and quantify label-free nucleic acids. This method is based on stoichiometric proportioning of phosphorus in the nucleic acid skeleton, using laser-induced breakdown spectroscopy, and a specific statistical analysis, which indicates the error probability for each measurement. The results obtained appear to be quantitative, with a limit of detection of 10 5 nucleotides/μm 2 (i.e. 2 x 10 13 phosphorus atoms/cm 2 ). Initial micro-array analysis has given very encouraging results, which point to new ways of quantifying hybridized nucleic acids. This is essential when comparing molecules of different sequences, which is presently very difficult with fluorescence labeling

  16. First improvements in the detection and quantification of label-free nucleic acids by laser-induced breakdown spectroscopy: Application to the deoxyribonucleic acid micro-array technology

    Energy Technology Data Exchange (ETDEWEB)

    Le Meur, Julien [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Menut, Denis [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Wodling, Pascal [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Salmon, Laurent [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Thro, Pierre-Yves [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Chevillard, Sylvie [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Ugolin, Nicolas [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France)], E-mail: nugolin@cea.fr

    2008-04-15

    The accurate quantification of nucleic acids is essential in many fields of modern biology and industry, and in some cases requires the use of fluorescence labeling. Yet, in addition to standardization problems and quantification reproducibility, labeling can modify the physicochemical properties of molecules or affect their stability. To address these limitations, we have developed a novel method to detect and quantify label-free nucleic acids. This method is based on stoichiometric proportioning of phosphorus in the nucleic acid skeleton, using laser-induced breakdown spectroscopy, and a specific statistical analysis, which indicates the error probability for each measurement. The results obtained appear to be quantitative, with a limit of detection of 10{sup 5} nucleotides/{mu}m{sup 2} (i.e. 2 x 10{sup 13} phosphorus atoms/cm{sup 2}). Initial micro-array analysis has given very encouraging results, which point to new ways of quantifying hybridized nucleic acids. This is essential when comparing molecules of different sequences, which is presently very difficult with fluorescence labeling.

  17. Microemulsion formulation of clonixic acid: solubility enhancement and pain reduction.

    Science.gov (United States)

    Lee, Jung-Mi; Park, Kyung-Mi; Lim, Soo-Jeong; Lee, Mi-Kyung; Kim, Chong-Kook

    2002-01-01

    Clonixic acid is currently marketed as a salt form because of its poor water-solubility. However, the commercial dosage form causes severe pain after intramuscular or intravenous injection. To improve the solubility of clonixic acid and to reduce pain on injection, clonixic acid was incorporated into oil-in-water microemulsions prepared from pre-microemulsion concentrate composed of varying ratios of oil and surfactant mixture. As an oil phase for drug incorporation, up to 14% castor oil could be included in the pre-microemulsion concentrate without a significant increase in droplet size. Both drug contents and droplet size increased as the weight ratio of Tween 20 to Tween 85 decreased. Taken together, when microemulsions were prepared from pre-microemulsion concentrate composed of 5:12:18 weight ratio of castor oil:Tween 20:Tween 85, clonixic acid could be incorporated at 3.2 mg mL(-1) in the microemulsion with a droplet size of less than 120 nm. The osmotic pressure of this microemulsion was remarkably lower than the commercial formulation, irrespective of the dilution ratios. The rat paw-lick test was used to compare pain responses among formulations. The microemulsion formulation significantly reduced the number of rats licking their paws as well as the total licking time, suggesting less pain induction by the microemulsion formulation. The pharmacokinetic parameters of clonixic acid after intravenous administration of the clonixic acid microemulsion to rats were not significantly different from those of the commercial formulation, lysine clonixinate. The present study suggests that microemulsion is an alternative formulation for clonixic acid with improved characteristics.

  18. How cocrystals of weakly basic drugs and acidic coformers might modulate solubility and stability.

    Science.gov (United States)

    Kuminek, G; Rodríguez-Hornedo, N; Siedler, S; Rocha, H V A; Cuffini, S L; Cardoso, S G

    2016-04-30

    Cocrystals of a weakly basic drug (nevirapine) with acidic coformers are shown to alter the solubility dependence on pH, and to exhibit a pHmax above which a less soluble cocrystal becomes more soluble than the drug. The cocrystal solubility advantage can be dialed up or down by solution pH.

  19. Synthesis of acid-soluble spore proteins by Bacillus subtilis.

    OpenAIRE

    Leventhal, J M; Chambliss, G H

    1982-01-01

    The major acid-soluble spore proteins (ASSPs) of Bacillus subtilis were detected by immunoprecipitation of radioactively labeled in vitro- and in vivo-synthesized proteins. ASSP synthesis in vivo began 2 h after the initiation of sporulation (t2) and reached its maximum rate at t7. This corresponded to the time of synthesis of mRNA that stimulated the maximum rate of ASSP synthesis in vitro. Under the set of conditions used in these experiments, protease synthesis began near t0, alkaline phos...

  20. Identification of Three Kinds of Citri Reticulatae Pericarpium Based on Deoxyribonucleic Acid Barcoding and High-performance Liquid Chromatography-diode Array Detection-electrospray Ionization/Mass Spectrometry/Mass Spectrometry Combined with Chemometric Analysis

    Science.gov (United States)

    Yu, Xiaoxue; Zhang, Yafeng; Wang, Dongmei; Jiang, Lin; Xu, Xinjun

    2018-01-01

    Background: Citri Reticulatae Pericarpium is the dried mature pericarp of Citrus reticulata Blanco which can be divided into “Chenpi” and “Guangchenpi.” “Guangchenpi” is the genuine Chinese medicinal material in Xinhui, Guangdong province; based on the greatest quality and least amount, it is most expensive among others. Hesperidin is used as the marker to identify Citri Reticulatae Pericarpium described in the Chinese Pharmacopoeia 2010. However, both “Chenpi” and “Guangchenpi” contain hesperidin so that it is impossible to differentiate them by measuring hesperidin. Objective: Our study aims to develop an efficient and accurate method to separate and identify “Guangchenpi” from other Citri Reticulatae Pericarpium. Materials and Methods: The genomic deoxyribonucleic acid (DNA) of all the materials was extracted and then the internal transcribed spacer 2 was amplified, sequenced, aligned, and analyzed. The secondary structures were created in terms of the database and website established by Jörg Schultz et al. High-performance liquid chromatography-diode array detection-electrospray Ionization/mass spectrometry (HPLC-DAD-ESI-MS)/MS coupled with chemometric analysis was applied to compare the differences in chemical profiles of the three kinds of Citri Reticulatae Pericarpium. Results: A total of 22 samples were classified into three groups. The results of DNA barcoding were in accordance with principal component analysis and hierarchical cluster analysis. Eight compounds were deduced from HPLC-DAD-ESI-MS/MS. Conclusions: This method is a reliable and effective tool to differentiate the three Citri Reticulatae Pericarpium. SUMMARY The internal transcribed spacer 2 regions and the secondary structure among three kinds of Citri Reticulatae Pericarpium varied considerablyAll the 22 samples were analyzed by high-performance liquid chromatography (HPLC) to obtain the chemical profilesPrincipal component analysis and hierarchical cluster analysis

  1. Solubility of nickel-cadmium ferrite in acids

    International Nuclear Information System (INIS)

    Vol'ski, V.; Vol'ska, Eh.; Politan'ska, U.

    1977-01-01

    The solubility of a solid solution of nickel-cadmium ferrite containing an excess of ferric oxide, (CdO)sub(0.5), (NiO)sub(0.5) and (Fe 2 O 3 )sub(1.5), in hydrochloric and nitric acids at 20, 40 and 60 deg C, was determined colorimetrically and chelatometrically, as well as by studying the x-ray diffraction patterns of the preparations prior to dissolution and their residues after dissolution. It is shown that cadmium passes into the solution faster than iron and nickel; after 800 hours, the solution contains 40% of iron ions and more than 80% of cadmium ions. The kinetics of ferrite dissolution is studied

  2. Intrinsic solubility estimation and pH-solubility behavior of cosalane (NSC 658586), an extremely hydrophobic diprotic acid.

    Science.gov (United States)

    Venkatesh, S; Li, J; Xu, Y; Vishnuvajjala, R; Anderson, B D

    1996-10-01

    The selection of cosalane (NSC 658586) by the National Cancer Institute for further development as a potential drug candidate for the treatment of AIDS led to the exploration of the solubility behavior of this extremely hydrophobic drug, which has an intrinsic solubility (S0 approaching 1 ng/ml. This study describes attempts to reliably measure the intrinsic solubility of cosalane and examine its pH-solubility behavior. S0 was estimated by 5 different strategies: (a) direct determination in an aqueous suspension: (b) facilitated dissolution; (c) estimation from the octanol/water partition coefficient and octanol solubility (d) application of an empirical equation based on melting point and partition coefficient; and (e) estimation from the hydrocarbon solubility and functional group contributions for transfer from hydrocarbon to water. S0 estimates using these five methods varied over a 5 x 107-fold range Method (a) yielded the highest values, two-orders of magnitude greater than those obtained by method (b) (facilitated dissolution. 1.4 +/- 0.5 ng/ml). Method (c) gave a value 20-fold higher while that from method (d) was in fair agreement with that from facilitated dissolution. Method (e) yielded a value several orders-of-magnitude lower than other methods. A molecular dynamics simulation suggests that folded conformations not accounted for by group contributions may reduce cosalane's effective hydrophobicity. Ionic equilibria calculations for this weak diprotic acid suggested a 100-fold increase in solubility per pH unit increase. The pH-solubility profile of cosalane at 25 degrees C agreed closely with theory. These studies highlight the difficulty in determining solubility of very poorly soluble compounds and the possible advantage of the facilitated dissolution method. The diprotic nature of cosalane enabled a solubility enhancement of > 107-fold by simple pH adjustment.

  3. Time-resolved studies of energy transfer from meso-tetrakis(N-methylpyridinium-4-yl)- porphyrin to 3,3'-diethyl-2,2'-thiatricarbocyanine iodide along deoxyribonucleic acid Chain.

    Science.gov (United States)

    Kakiuchi, Toshifumi; Ito, Fuyuki; Nagamura, Toshihiko

    2008-04-03

    The excitation energy transfer from meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) to 3,3'-diethyl-2,2'-thiatricarbocyanine iodide (DTTCI) along the deoxyribonucleic acid (DNA) double strand was investigated by the steady-state absorption and fluorescence measurements and time-resolved fluorescence measurements. The steady-state fluorescence spectra showed that the near-infrared fluorescence of DTTCI was strongly enhanced up to 86 times due to the energy transfer from the excited TMPyP molecule in DNA buffer solution. Furthermore, we elucidated the mechanism of fluorescence quenching and enhancement by the direct observation of energy transfer using the time-resolved measurements. The fluorescence quenching of TMPyP chiefly consists of a static component due to the formation of complex and dynamic components due to the excitation energy transfer. In a heterogeneous one-dimensional system such as a DNA chain, it was proved that the energy transfer process only carries out within the critical distance based on the Förster theory and within a threshold value estimated from the modified Stern-Volmer equation. The present results showed that DNA chain is one of the most powerful tools for nanoassemblies and will give a novel concepts of material design.

  4. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol-Water Mixtures

    NARCIS (Netherlands)

    Bowden, Nathan A.; Sanders, Johan P.M.; Bruins, Marieke E.

    2018-01-01

    The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization. We reviewed the available data on the solubility of α-amino acids in water, water-ethanol mixtures, and ethanol at 298.15 K and 0.1 MPa. The solubility of l-alanine, l-proline,

  5. Synthesis of acid-soluble spore proteins by Bacillus subtilis.

    Science.gov (United States)

    Leventhal, J M; Chambliss, G H

    1982-12-01

    The major acid-soluble spore proteins (ASSPs) of Bacillus subtilis were detected by immunoprecipitation of radioactively labeled in vitro- and in vivo-synthesized proteins. ASSP synthesis in vivo began 2 h after the initiation of sporulation (t2) and reached its maximum rate at t7. This corresponded to the time of synthesis of mRNA that stimulated the maximum rate of ASSP synthesis in vitro. Under the set of conditions used in these experiments, protease synthesis began near t0, alkaline phosphatase synthesis began at about t2, and refractile spores were first observed between t7 and t8. In vivo- and in vitro-synthesized ASSPs comigrated in sodium dodecyl sulfate-polyacrylamide gels. Their molecular weights were 4,600 (alpha and beta) and 11,000 (gamma). The average half-life of the ASSP messages was 11 min when either rifampin (10 micrograms/ml) or actinomycin D (1 microgram/ml) was used to inhibit RNA synthesis.

  6. Small acid soluble proteins for rapid spore identification.

    Energy Technology Data Exchange (ETDEWEB)

    Branda, Steven S.; Lane, Todd W.; VanderNoot, Victoria A.; Jokerst, Amanda S.

    2006-12-01

    This one year LDRD addressed the problem of rapid characterization of bacterial spores such as those from the genus Bacillus, the group that contains pathogenic spores such as B. anthracis. In this effort we addressed the feasibility of using a proteomics based approach to spore characterization using a subset of conserved spore proteins known as the small acid soluble proteins or SASPs. We proposed developing techniques that built on our previous expertise in microseparations to rapidly characterize or identify spores. An alternative SASP extraction method was developed that was amenable to both the subsequent fluorescent labeling required for laser-induced fluorescence detection and the low ionic strength requirements for isoelectric focusing. For the microseparations, both capillary isoelectric focusing and chip gel electrophoresis were employed. A variety of methods were evaluated to improve the molecular weight resolution for the SASPs, which are in a molecular weight range that is not well resolved by the current methods. Isoelectric focusing was optimized and employed to resolve the SASPs using UV absorbance detection. Proteomic signatures of native wild type Bacillus spores and clones genetically engineered to produce altered SASP patterns were assessed by slab gel electrophoresis, capillary isoelectric focusing with absorbance detection as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection.

  7. Salt and cocrystals of sildenafil with dicarboxylic acids: solubility and pharmacokinetic advantage of the glutarate salt.

    Science.gov (United States)

    Sanphui, Palash; Tothadi, Srinu; Ganguly, Somnath; Desiraju, Gautam R

    2013-12-02

    Sildenafil is a drug used to treat erectile dysfunction and pulmonary arterial hypertension. Because of poor aqueous solubility of the drug, the citrate salt, with improved solubility and pharmacokinetics, has been marketed. However, the citrate salt requires an hour to reach its peak plasma concentration. Thus, to improve solubility and bioavailability characteristics, cocrystals and salts of the drug have been prepared by treating aliphatic dicarboxylic acids with sildenafil; the N-methylated piperazine of the drug molecule interacts with the carboxyl group of the acid to form a heterosynthon. Salts are formed with oxalic and fumaric acid; salt monoanions are formed with succinic and glutaric acid. Sildenafil forms cocrystals with longer chain dicarboxylic acids such as adipic, pimelic, suberic, and sebacic acids. Auxiliary stabilization via C-H···O interactions is also present in these cocrystals and salts. Solubility experiments of sildenafil cocrystal/salts were carried out in 0.1N HCl aqueous medium and compared with the solubility of the citrate salt. The glutarate salt and pimelic acid cocrystal dissolve faster than the citrate salt in a two hour dissolution experiment. The glutarate salt exhibits improved solubility (3.2-fold) compared to the citrate salt in water. Solubilities of the binary salts follow an inverse correlation with their melting points, while the solubilities of the cocrystals follow solubilities of the coformer. Pharmacokinetic studies on rats showed that the glutarate salt exhibits doubled plasma AUC values in a single dose within an hour compared to the citrate salt. The high solubility of glutaric acid, in part originating from the strained conformation of the molecule and its high permeability, may be the reason for higher plasma levels of the drug.

  8. Bilateral lesions of suprachiasmatic nuclei affect circadian rhythms in [3H]-thymidine incorporation into deoxyribonucleic acid in mouse intestinal tract, mitotic index of corneal epithelium, and serum corticosterone

    International Nuclear Information System (INIS)

    Scheving, L.E.; Tsai, T.H.; Powell, E.W.; Pasley, J.N.; Halberg, F.; Dunn, J.

    1983-01-01

    Investigations into the role of the suprachiasmatic nuclei (SCN) in the coordination of circadian rhythms have presented differing results. Several reports have shown that ablation of the suprachiasmatic nuclei (SCNA) alters the phase and amplitude of rhythms but does not abolish them. The present study investigates the effect of SCNA on the rhythms in cell proliferation in various regions of the intestinal tract as measured by the incorporation of [ 3 H]-thymidine into deoxyribonucleic acid, in the mitotic activity of the corneal epithelium, and in serum corticosterone levels. The study involved mice with verified lesions of the SCN (six to 13 mice per time point) and control groups of both sham-operated and unoperated mice (seven of each per time point). The mice were killed in groups that represented seven time points over a single 24 hr span (3 hr intervals with the 0800 hr sampled both at start and end of the series). The tissues examined were the tongue, esophagus, gastric stomach, and colon for DNA synthesis, the corneal epithelium for mitotic index, and blood serum for corticosterone level. The most consistent result of SCNA was a phase advance in the rhythms in cell proliferation in the tongue, esophagus, gastric stomach, colon, and corneal epithelium. A reduction in rhythm amplitude occurred in the tongue, esophagus, and corneal epithelium; however, there was an amplitude increase for the stomach, colon, and serum corticosterone. The mesor (rhythm-adjusted mean) was increased by SCNA in all tissues except the corneal epithelium. These findings further support the role of the suprachiasmatic nuclear area in the control of rhythms in cell proliferation and corticosterone production, by acting as a ''phase-resetter'' and as a modulator of rhythm amplitude

  9. Deoxyribonucleic acid directed metallization of platinum nanoparticles on graphite nanofibers as a durable oxygen reduction catalyst for polymer electrolyte fuel cells

    Science.gov (United States)

    Peera, S. Gouse; Sahu, A. K.; Arunchander, A.; Nath, Krishna; Bhat, S. D.

    2015-11-01

    Effective surface functionalization to the hydrophobic graphite nanofibers (GNF) is performed with the biomolecule, namely deoxy-ribo-nucleic-acid (DNA) via π-π interactions. Pt nanoparticles are impregnated on GNF-DNA composite by ethylene glycol reduction method (Pt/GNF-DNA) and its effect on electro catalytic activity for oxygen reduction reaction (ORR) is systemically studied. Excellent dispersion of Pt nanoparticles over GNF-DNA surfaces with no evidence on particle aggregation is a remarkable achievement in this study. This result in higher electro chemical surface area of the catalyst, enhanced ORR behavior with significant enhancement in mass activity. The catalyst is validated in H2-O2 polymer electrolyte fuel cell (PEFC) and a peak power density of 675 mW cm-2 is achieved at a load current density of 1320 mA cm-2 with a minimal catalyst loading of 0.1 mg cm-2 at a cell temperature of 70 °C and 2 bar absolute pressure. Repeated potential cycling up to 10000 cycles in acidic media is also performed for this catalyst and found excellent stability with only 60 mV drop in the ORR half wave potential. The superior behavior of Pt/GNF-DNA catalyst is credited to the robust fibrous structure of GNF and its effective surface functionalization process via π-π interaction.

  10. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol–Water Mixtures

    Science.gov (United States)

    2018-01-01

    The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization. We reviewed the available data on the solubility of α-amino acids in water, water–ethanol mixtures, and ethanol at 298.15 K and 0.1 MPa. The solubility of l-alanine, l-proline, l-arginine, l-cysteine, and l-lysine in water and ethanol mixtures and the solubility of l-alanine, l-proline, l-arginine, l-cysteine, l-lysine, l-asparagine, l-glutamine, l-histidine, and l-leucine in pure ethanol systems were measured and are published here for the first time. The impact on the solubility of amino acids that can convert in solution, l-glutamic acid and l-cysteine, was studied. At lower concentrations, only the ninhydrin method and the ultraperfomance liquid chromatography (UPLC) method yield reliable results. In the case of α-amino acids that convert in solution, only the UPLC method was able to discern between the different α-amino acids and yields reliable results. Our results demonstrate that α-amino acids with similar physical structures have similar changes in solubility in mixed water/ethanol mixtures. The solubility of l-tryptophan increased at moderate ethanol concentrations. PMID:29545650

  11. Levels of acid-soluble polyphosphate in growing cultures of Saccharomyces cerevisiae.

    OpenAIRE

    Solimene, R; Guerrini, A M; Donini, P

    1980-01-01

    Short-chain acid-soluble polyphosphates were extracted from growing cultures of Saccharomyces cerevisiae, and the changes in the levels of these compounds were determined. The production of acid-soluble polyphosphates correlated with the mitochondrial activities since it occurred in two bursts in respiration-competent yeast cells and in only one burst in respiration-deficient yeast cells. The possible role of these compounds is discussed.

  12. Thermodynamic Solubility Profile of Carbamazepine-Cinnamic Acid Cocrystal at Different pH.

    Science.gov (United States)

    Keramatnia, Fatemeh; Shayanfar, Ali; Jouyban, Abolghasem

    2015-08-01

    Pharmaceutical cocrystal formation is a direct way to dramatically influence physicochemical properties of drug substances, especially their solubility and dissolution rate. Because of their instability in the solution, thermodynamic solubility of cocrystals could not be determined in the common way like other compounds; therefore, the thermodynamic solubility is calculated through concentration of their components in the eutectic point. The objective of this study is to investigate the effect of an ionizable coformer in cocrystal with a nonionizable drug at different pH. Carbamazepine (CBZ), a nonionizable drug with cinnamic acid (CIN), which is an acidic coformer, was selected to prepare CBZ-CIN cocrystal and its thermodynamic solubility was studied in pH range 2-7. Instead of HPLC that is a costly and time-consuming method, a chemometric-based approach, net analyte signal standard addition method, was selected for simultaneous determination of CBZ and CIN in solution. The result showed that, as pH increases, CIN ionization leads to change in CBZ-CIN cocrystal solubility and stability in solution. In addition, the results of this study indicated that there is no significant difference between intrinsic solubility of CBZ and cocrystal despite the higher ideal solubility of cocrystal. This verifies that ideal solubility is not good parameter to predict cocrystal solubility. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  13. Structure-property relationships in halogenbenzoic acids: Thermodynamics of sublimation, fusion, vaporization and solubility.

    Science.gov (United States)

    Zherikova, Kseniya V; Svetlov, Aleksey A; Kuratieva, Natalia V; Verevkin, Sergey P

    2016-10-01

    Temperature dependences of vapor pressures for 2-, 3-, and 4-bromobenzoic acid, as well as for five isomeric bromo-methylbenzoic acids were studied by the transpiration method. Melting temperatures and enthalpies of fusion for all isomeric bromo-methylbenzoic acids and 4-bromobenzoic acid were measured with a DSC. The molar enthalpies of sublimation and vaporization were derived. These data together with results available in the literature were collected and checked for internal consistency using a group-additivity procedure and results from X-ray structural diffraction studies. Specific (hydrogen bonding) interactions in the liquid and in the crystal phase of halogenbenzoic acids were quantified based on experimental values of vaporization and sublimation enthalpies. Structure-property correlations of solubilities of halogenobenzoic acids with sublimation pressures and sublimation enthalpies were developed and solubilities of bromo-benzoic acids were estimated. These new results resolve much of the ambiguity in the available thermochemical and solubility data on bromobenzoic acids. The approach based on structure property correlations can be applied for the assessment of water solubility of sparingly soluble drugs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. A comparative study on the interaction of phenazinium dyes with low pH induced protonated structure and B-form structure of naturally occurring deoxyribonucleic acid

    International Nuclear Information System (INIS)

    Pradhan, Ankur Bikash; Das, Shubhajit; Haque, Lucy; Bhuiya, Sutanwi; Das, Suman

    2016-01-01

    The interaction of two phenazinium dyes namely Phenosafranine (PSF) and Safranin T (ST) with right-handed B-form and left-handed protonated form of Calf Thymus (CT) DNA was investigated using different spectroscopic techniques. Both the dyes have been shown to bind strongly to the right-handed B-form of DNA by the mechanism intercalation as revealed from fluorescence quenching, circular dichroism (CD) and viscosity measurement. From circular dichroic studies it was evidenced that both of them convert the low pH induced left-handed protonated form of DNA back to the bound right-handed form. Scatchard analysis showed that both the dyes bound strongly to B-form of DNA in a non-cooperative manner. In case of protonated form, there was sequential conversion of the polynucleotide from left-handed to the bound right-handed conformation. Our results suggest that the binding environment of the dyes in the two forms of DNA is similar and our data predict that PSF is more effective in the conversion than ST. Experimental data enabled the calculation of the number of base pairs of protonated-form that adopted a right-handed conformation for each bound dye. Our data revealed that PSF is more effective in the conversion compard to that of ST. These results are attributed to greater steric crowd in ST compared to PSF which restricts the former to intercalate between DNA base pairs. The results of these studies allow a better understanding of dye-polymorphic nucleic acid interactions at a molecular level.

  15. Investigations on uranyl nitrate solubility in nitric acid in different concentrations at temperatures of 50C

    International Nuclear Information System (INIS)

    Deigele, E.

    1983-01-01

    The solubility of uranyl nitrate was studied in nitric acid solutions of different concentrations at a temperature of 5 0 C. This temperature was chosen with a view to using water as coolant and to facilitate the handling of the strong acid solutions. Accurate curves were established by a multitude of accurate measurements in the high concentration range. Further solubility curves can be derived from this basic curve. Some of the precipitates in the interesting regions of the solubility curve were analyzed. (orig./EF) [de

  16. A facile physical approach to make chitosan soluble in acid-free water.

    Science.gov (United States)

    Fu, Yinghao; Xiao, Congming

    2017-10-01

    We changed the situation that chitosan was only dissolved in diluted acid through mild physical treatment. In viewing of the usual methods to modify chitosan are chemical ones, we established the approach by using a water-soluble chitosan derivative as the model polymer. Its water-solubility was modulated via changing the concentration of solution and varying the precipitants. Such a physical method was adopted to treat chitiosan. One gram chitosan was dissolved in a mixture of 100mL 10% acetic acid and 50mL methanol, and then precipitated from a precipitant consisted of 10mL ethanol and 90mL acetate ester. The treated chitosan became soluble in acid-free water completely, and its solubility was 8.02mg/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Solubilities of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures

    International Nuclear Information System (INIS)

    Wang, Hui; Wang, Qinbo; Xiong, Zhenhua; Chen, Chuxiong; Shen, Binwei

    2015-01-01

    Highlights: • Solubilities of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were measured at 1 atm. • The experimental temperature ranges at (298.35 to 355.65) K. • Effects of benzyl alcohol mass concentration at (0.00 to 1.00) on the solubilities of benzoic acid were studied. • The experimental data were correlated with NRTL model. • Thermodynamic functions of dissolution of benzoic acid in (benzyl alcohol + benzaldehyde) mixtures were discussed. - Abstract: The solubility of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures was measured at temperature from (298.35 to 355.65) K and atmospheric pressure. The measured solubility increases with the increasing temperature at constant solvent composition. The effects of mass fraction benzaldehyde in the solvent mixtures at (0.0 to 1.00) on the solubility were studied. The measured solubility decreases with the increasing mass fraction of benzaldehyde. The experimental results were correlated with the non-random two-liquid (NRTL) equations, and good agreement between the correlated and the experimental values was obtained. Thermodynamic functions for the solution of benzoic acid in binary (benzyl alcohol + benzaldehyde) solvent mixtures were calculated with the van’t Hoff plot. The apparent dissolution Gibbs free energy change was also calculated

  18. An estimation of influence of humic acid and organic matter originated from bentonite on samarium solubility

    International Nuclear Information System (INIS)

    Kanaji, Mariko; Sato, Haruo; Sasahira, Akira

    1999-10-01

    Organic acids in groundwater are considered to form complexes and increase the solubility of radionuclides released from vitrified waste in a high-level radioactive waste (HLW) repository. To investigate whether the solubility of samarium (Sm) is influenced by organic substances, we measured Sm solubility in the presence of different organic substances and compared those values with results from thermodynamic predictions. Humic acid (Aldrich) is commercially available and soluble organic matter originated from bentonite were used as organic substances in this study. Consequently, the solubility of Sm showed a tendency to apparently increase with increasing the concentration of humic acid, but in the presence of carbonate, thermodynamic predictions suggested that the dominant species are carbonate complexes and that the effect of organic substances are less than that of carbonate. Based on total organic carbon (TOC), the increase of Sm solubility measured with humic acid (Aldrich) was more significant than that in the case with soluble organic matter originated from bentonite. Since bentonite is presumed to include also simple organic matters of which stability constant for forming complexes is low, the effect of soluble organic matter originated from bentonite on the solubility of Sm is considered to be less effective than that of humic acid (Aldrich). Experimental values were compared with model prediction, proposed by Kim, based on data measured in a low pH region. Tentatively we calculated the increase in Sm solubility assuming complexation with humic acid. Trial calculations were carried out on the premise that the complexation reaction of metal ion with humic acid is based on neutralization process by 1-1 complexation. In this process, it was assumed that one metal ion coordinates with one unit of complexation sites which number of proton exchange sites is equal to ionic charge. Consequently, Kim's model indicated that carbonate complexes should be dominant

  19. Density, viscosity, and N2O solubility of aqueous amino acid salt and amine amino acid salt solutions

    International Nuclear Information System (INIS)

    Aronu, Ugochukwu E.; Hartono, Ardi; Svendsen, Hallvard F.

    2012-01-01

    Highlights: ► Density of amino acid salt and amine amino acid salt. ► Viscosity of amino acid salt and amine amino acid salt. ► Henry’s law constant/N 2 O solubility of amino acid salt and amine amino acid salt. ► Schumpe model. Correlations for density, viscosity, and N 2 O solubility. - Abstract: Physicochemical properties of aqueous amino acid salt (AAS), potassium salt of sarcosine (KSAR) and aqueous amine amino acid salt (AAAS), 3-(methylamino)propylamine/sarcosine (SARMAPA) have been studied. Densities of KSAR were measured for sarcosine mole fraction 0.02 to 0.25 for temperature range 298.15 K to 353.15 K, the viscosities were measured for 0.02 to 0.10 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.10 mole fraction sarcosine solutions (298.15 K to 363.15 K). Densities of SARMAPA were measured for sarcosine mole fraction 0.02 to 0.23 for temperature range (298.15 K to 353.15 K), viscosities were measured for 0.02 to 0.16 mole fraction sarcosine (293.15 K to 343.15 K) while the N 2 O solubilities were measured from 0.02 to 0.16 mole fraction sarcosine solutions (298.15 K to 343.15 K). Experimental results were correlated well with empirical correlations and N 2 O solubility results for KSAR were predicted adequately by a Schumpe model. The solubilities of N 2 O in AAS and AAAS are significantly lower than values for amines. The solubilities vary as: amine > AAAS > AAS.

  20. An odd–even effect on solubility of dicarboxylic acids in organic solvents

    International Nuclear Information System (INIS)

    Zhang, Hui; Yin, Qiuxiang; Liu, Zengkun; Gong, Junbo; Bao, Ying; Zhang, Meijing; Hao, Hongxun; Hou, Baohong; Xie, Chuang

    2014-01-01

    Highlights: • The solubilities of the homologous series of C2–C10 dicarboxylic acids were determined in four selected solvents. • The experimental data were well correlated with the modified Apelblat equation. • The odd–even effect of solubility was found and explained. • The enthalpy, entropy and the molar Gibbs free energy of solution were predicted. - Abstract: The solubility of the homologous series of dicarboxylic acids, HOOC-(CH 2 ) n−2 -COOH (n = 2 to 10), in ethanol, acetic acid, acetone and ethyl acetate was measured at temperatures ranging from (278.15 to 323.15) K by a static analytic method at atmospheric pressure. Dicarboxylic acids with even number of carbon atoms exhibit lower values of solubility than adjacent homologues with odd carbon numbers. This odd–even effect of solubility is attributed to the twist of molecules and interlayer packing in solid state as explained in our previous work. The alternation varies in different solvents, which is believed to be associated with the properties of solvents. Finally, the dissolution enthalpy, dissolution entropy and the molar Gibbs free energy were calculated using the fitting parameters of the modified Apelblat equation. The molar Gibbs free energy also showed apparent odd–even alternation in keeping with the alternation of solubility

  1. Protocol optimization for deoxyribonucleic acid (DNA) extraction ...

    African Journals Online (AJOL)

    MUNAWAR ROOMI

    2013-12-18

    Dec 18, 2013 ... research institutes, such as National Agricultural Research Centre. (NARC) .... and was experienced on soybean, chickpea seeds and wheat. When high ... suitable for molecular marker and transgenic analysis. Afr. J.

  2. Protocol optimization for deoxyribonucleic acid (DNA) extraction ...

    African Journals Online (AJOL)

    Arachis hypogaea L.) is particularly problematic due to the presence of phenolic compounds and polysaccharides. Inconsistencies in extraction results can be attributed to the age and growth stages of the plant material analyzed. Mature leaves ...

  3. Isolation of deoxyribonucleic acids (A Review)

    International Nuclear Information System (INIS)

    Garcia Pineda, M. de

    1974-01-01

    The criteria of choice in this Review have been to gather some of the last advances in the methodology of DNAs isolation; also the description of the generally accepted procedures has been emphasized. Only papers published before March 1974 are reviewed, because this work has been finished during this month. (Author) 109 refs

  4. The deoxyribonucleic acid of Micrococcus radiodurans

    Science.gov (United States)

    Schein, Arnold H.

    1966-01-01

    The DNA of Micrococcus radiodurans was prepared by three methods. Although the recovery of DNA varied considerably, the percentage molar base ratios of the DNA from the three preparations were essentially the same: guanine, 33±2; adenine, 18±1; cytosine, 33±2; thymine, 17±1. Base compositions calculated from Tm values and from density in caesium chloride gradients also yielded guanine+cytosine contents of 66 and 68% of total bases respectively. No unusual bases were observed. The S20,w values were characteristic of high-molecular-weight DNA. Electron microscopy showed the purified DNA in long strands; occasionally these were coiled. Images(a)(b)(c)(d)(e)Fig. 1. PMID:16742439

  5. Solubility of fumaric acid and its monosodium salt

    NARCIS (Netherlands)

    Roa Engel, C.A.; Horst, J.H. ter; Pieterse, M.; Wielen, L.A.M. van der; Straathof, A.J.J.

    2013-01-01

    Fumaric acid is a dicarboxylic acid applied in food industry and in some polymers. Currently, its fermentative production from renewable resources is receiving much attention, and crystallization is used to recover it. To determine the window of operation for crystallization from multicomponent

  6. CO2 Solubilities in Amide-based Brφnsted Acidic Ionic Liquids

    International Nuclear Information System (INIS)

    Palgunadi, Jelliarko; Im, Jin Kyu; Kang, Je Eun; Kim, Hoon Sik; Cheong, Min Serk

    2010-01-01

    A distinguished class of hydrophobic ionic liquids bearing a Brφnsted acidic character derived from amide-like compounds were prepared by a neutralization reaction of N,N-diethylformamide, N,N-dibutylformamide, 1-formylpiperidine, and ε-caprolactam with trifluoroacetic acid and physical absorptions of CO 2 in these ionic liquids were demonstrated and evaluated. CO 2 solubilities in these ionic liquids were influenced by the molecular structure of the cation and were apparently increased with the molar volume. Comparison based on a volume unit reveals that CO 2 solubilities in these liquids are relatively higher than those in imidazolium-based ionic liquids. Henry's coefficients calculated from low-pressure solubility tests at 313 to 333 K were used to derive the thermodynamics quantities. Enthalpy and entropy of solvation may share equal contributions in solubility

  7. Solubility of iron from combustion source particles in acidic media linked to iron speciation.

    Science.gov (United States)

    Fu, Hongbo; Lin, Jun; Shang, Guangfeng; Dong, Wenbo; Grassian, Vichi H; Carmichael, Gregory R; Li, Yan; Chen, Jianmin

    2012-10-16

    In this study, iron solubility from six combustion source particles was investigated in acidic media. For comparison, a Chinese loess (CL) dust was also included. The solubility experiments confirmed that iron solubility was highly variable and dependent on particle sources. Under dark and light conditions, the combustion source particles dissolved faster and to a greater extent relative to CL. Oil fly ash (FA) yielded the highest soluble iron as compared to the other samples. Total iron solubility fractions measured in the dark after 12 h ranged between 2.9 and 74.1% of the initial iron content for the combustion-derived particles (Oil FA > biomass burning particles (BP) > coal FA). Ferrous iron represented the dominant soluble form of Fe in the suspensions of straw BP and corn BP, while total dissolved Fe presented mainly as ferric iron in the cases of oil FA, coal FA, and CL. Mössbauer measurements and TEM analysis revealed that Fe in oil FA was commonly presented as nanosized Fe(3)O(4) aggregates and Fe/S-rich particles. Highly labile source of Fe in corn BP could be originated from amorphous Fe form mixed internally with K-rich particles. However, Fe in coal FA was dominated by the more insoluble forms of both Fe-bearing aluminosilicate glass and Fe oxides. The data presented herein showed that iron speciation varies by source and is an important factor controlling iron solubility from these anthropogenic emissions in acidic solutions, suggesting that the variability of iron solubility from combustion-derived particles is related to the inherent character and origin of the aerosols themselves. Such information can be useful in improving our understanding on iron solubility from combustion aerosols when they undergo acidic processing during atmospheric transport.

  8. Solubility of gallic acid in liquid mixtures of (ethanol + water) from (293.15 to 318.15) K

    International Nuclear Information System (INIS)

    Noubigh, Adel; Jeribi, Chokri; Mgaidi, Arbi; Abderrabba, Manef

    2012-01-01

    Graphical abstract: Solubility of gallic acid vs the mole fraction of ethanol (0.0 to 1) on a solute-free basis in ethanol + water at different temperatures/K. □, 293.15; Δ, 298.15; ◊, 303.15; line calculated by equation. Highlights: ► Solubilities of gallic acid in binary mixtures were determined over the temperatures range (293.15 to 318.15) K. ► The gallic acid solubility in mixed solvents presents a maximum-solubility effect. ► Two empirical equations were proposed to correlate the solubility Data. ► The thermodynamic properties were determined. - Abstract: The solubility of gallic acid in (water + ethanol) binary solvents was determined from (293.15 to 318.15) K at atmospheric pressure using a thermostatted reactor and UV/vis spectrophotometer analysis. The effects of binary solvents composition and temperature on the solubility were discussed. It was found that gallic acid solubility in (water + ethanol) mixed solvents presents a maximum-solubility effect. Two empirical equations were proposed to correlate the solubility data. The calculated solubilities show good agreement with the experimental data within the studied temperature range. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of the gallic acid such as Gibbs energy (Δ sol G°), molar enthalpy of dissolution (Δ sol H°), and molar entropy of dissolution (Δ sol S°) were calculated.

  9. Solubility of 3-Caffeoylquinic Acid in Different Solvents at 291-340 K

    Science.gov (United States)

    Wang, Y. T.; Zhang, C. L.; Cheng, X. L.; Zhao, J. H.; Wang, L. C.

    2017-12-01

    Using a laser monitoring observation technique the solubilities of 3-caffeoylquinic acid in pure solvents, water, methanol, ethanol, 1-propanol, 1-butanol, and two mixed solvents, methanol + water, ethanol + water have been determined at temperature range from 291-340 K. The experimental data were correlated by the modified Apelblat equation, λ h equation, and ideal model. The calculated solubilities were turned out very consistent with the experimental results, and the modified Apelblat equation shows the best agreement.

  10. Efficient Enzymatic Synthesis of Phenolic Ester by Increasing Solubility of Phenolic Acids in Ionic Liquids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    Compounds from phenolic acid family are well known natural antioxidants, but the application of phenolic acids as antioxidants in industry is limited due to the relatively low solubility in oil-based media. The properties of phenolic acids can be modified through enzymatic lipophilization...... and modified phenolic acids will have amphiphilic property, therefore they can be localized at oil-water or water-oil phase where oxidation is considered to occur frequently. It had been reported that immobilized Candida Antarctica lipase B was the most effective biocatalyst for the various esterification...... reactions, and it had been widely used for esterification of various phenolic acids with fatty alcohol or triglycerides. However, the conversion of phenolic acids is low due to low solubility in hydrophobic solvents and hindrance effect of unsaturated side chain towards the enzyme. Our studies show...

  11. Impact of the counterion on the solubility and physicochemical properties of salts of carboxylic acid drugs.

    Science.gov (United States)

    David, S E; Timmins, P; Conway, B R

    2012-01-01

    Salt formation is a widely used approach to improve the physicochemical and solid state properties of an active pharmaceutical ingredient. In order to better understand the relationships between the active drug, the selected counterion and the resultant salt form, crystalline salts were formed using four different carboxylic acid drugs and a closely related series of amine counterions. Thirty-six related crystalline salts were prepared, characterized and the relationship between solubility and dissolution behaviour and other properties of the salt and the counterion studied. Salts of four model acid drugs, gemfibrozil, flurbiprofen, ibuprofen and etodolac were prepared using the counterions butylamine, hexylamine, octylamine, benzylamine, cyclohexylamine, tert-butylamine, 2-amino-2-methylpropan-1-ol, 2-amino-2-methylpropan-1,3-diol and tris(hydroxymethyl)aminomethane. Salt formation was confirmed, the salts were characterized and their corresponding solubilities determined and rationalized with respect to the counterions' properties. The properties of the salt highly dependent on the nature of the counterion and, although there is considerable variation, some general conclusion can be drawn. For the alkyl amines series, increasing chain length leads to a reduction in solubility across all the acidic drugs studied and a reduction in melting point, thus contradicting simplistic relationships between solubility and melting point. Small, compact counterions consistently produce crystalline salts with high melting point accompanied with a modest improvement in solubility and the nature of hydrogen bonding between the ions has a major impact on the solubility.

  12. Drug Solubility in Fatty Acids as a Formulation Design Approach for Lipid-Based Formulations: A Technical Note.

    Science.gov (United States)

    Lee, Yung-Chi; Dalton, Chad; Regler, Brian; Harris, David

    2018-06-06

    Lipid-based drug delivery systems have been intensively investigated as a means of delivering poorly water-soluble drugs. Upon ingestion, the lipases in the gastrointestinal tract digest lipid ingredients, mainly triglycerides, within the formulation into monoglycerides and fatty acids. While numerous studies have addressed the solubility of drugs in triglycerides, comparatively few publications have addressed the solubility of drugs in fatty acids, which are the end product of digestion and responsible for the solubility of drug within mixed micelles. The objective of this investigation was to explore the solubility of a poorly water-soluble drug in fatty acids and raise the awareness of the importance of drug solubility in fatty acids. The model API (active pharmaceutical ingredient), a weak acid, is considered a BCS II compound with an aqueous solubility of 0.02 μg/mL and predicted partition coefficient >7. The solubility of API ranged from 120 mg/mL to over 1 g/mL in fatty acids with chain lengths across the range C18 to C6. Hydrogen bonding was found to be the main driver of the solubilization of API in fatty acids. The solubility of API was significantly reduced by water uptake in caprylic acid but not in oleic acid. This report demonstrates that solubility data generated in fatty acids can provide an indication of the solubility of the drug after lipid digestion. This report also highlights the importance of measuring the solubility of drugs in fatty acids in the course of lipid formulation development.

  13. The performance of a soluble lead-acid flow battery and its comparison to a static lead-acid battery

    International Nuclear Information System (INIS)

    Zhang, C.P.; Sharkh, S.M.; Li, X.; Walsh, F.C.; Zhang, C.N.; Jiang, J.C.

    2011-01-01

    Highlights: → We compared the electrochemical characteristics of two types of the batteries. → SLAFB shows as good performance as SLAB under the same current density. → The cycle life of two batteries is strongly influenced by the depth of discharge. → The cycle life of SLAFB can be extended by treatment with hydrogen peroxide. - Abstract: The electrochemistry of static lead-acid and soluble lead-acid flow batteries is summarised and the differences between the two batteries are highlighted. A general comparison of the performance of an unoptimised soluble lead-acid flow laboratory cell and a commercial lead-acid battery during charge and discharge is reported. The influence of the depth of discharge on cycle life for both batteries is also considered. The flow battery was found to have a better charge efficiency than the static one, but the cells were found to have comparable energy efficiencies. The self-discharge characteristics of the soluble lead-acid battery were also measured and compared to reported values for a commercial static battery. Some self-discharge of the soluble lead-acid flow battery is observed during prolonged periods on open-circuit but the battery could recover its normal performance after a single charge-discharge cycle.

  14. Properties of spores of Bacillus subtilis strains which lack the major small, acid-soluble protein

    International Nuclear Information System (INIS)

    Hackett, R.H.; Setlow, P.

    1988-01-01

    Bacillus subtilis strains containing a deletion in the gene coding for the major small, acid-soluble, spore protein (SASP-gamma) grew and sporulated, and their spores initiated germination normally, but outgrowth of SASP-gamma- spores was significantly slower than that of wild-type spores. The absence of SASP-gamma had no effect on spore protoplast density or spore resistance to heat or radiation. Consequently, SASP-gamma has a different function in spores than do the other major small, acid-soluble proteins

  15. Estimation of solubility of organo-phosphorus extractants by P determination using molybdovanadophosphoric acid method

    International Nuclear Information System (INIS)

    Gill, J.S.; Kotekar, M.K.; Singh, H.

    2005-01-01

    Solvent extraction processes have been found to be suitable for uranium recovery from phosphoric acid. Various extractants like di-2-ethyl hexylphosphoric acid (D2EHPA), di-nonylphenyl phosphoric acid (DNPPA) and synergistic agents like tri-butyl phosphate (TBP), tri-octyl phosphine oxide (TOPO) have been used in liquid-liquid extraction of uranium from phosphoric acid. Contents of these organo-phosphorus compounds in aqueous raffinates need estimation for process requirements. Solubility of Tri-butyl phosphate (TBP) and Di-2-ethylhexyl phosphoric acid (D2EHPA) extractants have been determined in different media of water, oxalic acid (0.6M) and sulphuric acid (3.75M) solutions. These compounds were estimated by determining their phosphorus (P) contents employing molybdovanadophosphoric acid method, after digesting and solubalizing them in nitric and perchloric acid. (author)

  16. CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

    Directory of Open Access Journals (Sweden)

    S. S. Hings

    2008-07-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (dm<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (dcore≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

  17. Solubility of nicotinic acid in water, ethanol, acetone, diethyl ether, acetonitrile, and dimethyl sulfoxide

    International Nuclear Information System (INIS)

    Gonçalves, Elsa M.; Minas da Piedade, Manuel E.

    2012-01-01

    Highlights: ► We determined the solubility of nicotinic acid in six solvents by the gravimetric method. ► We found that, regardless of the solvent, the same monoclinic solid phase was in equilibrium with the solution. ► We determined the activity coefficients of nicotinic acid in the six solvents. ► We found that the solubility trends seem to be determined by the polarity and polarizability of the solvent. - Abstract: The mole fraction equilibrium solubility of nicotinic acid in six solvents (water, ethanol, dimethyl sulfoxide, acetone, acetonitrile and diethyl ether) differing in polarity, polarizability, and hydrogen-bonding ability, was determined over the temperature range (283 to 333) K, using the gravimetric method. The results obtained led to the solubility order dimethyl sulfoxide (DMSO) ≫ ethanol > water > acetone > diethyl ether > acetonitrile. An analysis based on various solvent descriptors, indicated that this trend seems to be mainly determined by the polarity and polarizability of the solvent. The activity coefficients of nicotinic acid in the different solvents, under saturation conditions, were determined as a function of the temperature and it was found that DMSO exhibits enhanced solubility relative to an ideal solution while the opposite is observed for all other solvents. Both the solvent and the fact that nicotinic acid is primarily zwitterionic in aqueous solution and non-zwitterionic in non-aqueous media, did not affect the nature of the solid phases in equilibrium with the different solutions. Indeed, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and differential scanning calorimetry analysis indicated that, despite some differences in particle size and morphology, the starting material and the solid products obtained at the end of the solubility studies in the six solvents used in this work were all crystalline and corresponded to the same monoclinic phase.

  18. Solubility Testing of Sucrose Esters of Fatty Acids in International Food Additive Specifications.

    Science.gov (United States)

    Nagai, Yukino; Kawano, Satoko; Motoda, Kenichiro; Tomida, Masaaki; Tatebe, Chiye; Sato, Kyoko; Akiyama, Hiroshi

    2017-03-01

    We investigated the solubility of 10 samples of sucrose esters of fatty acids (SEFA) products that are commercially available worldwide as food additives (emulsifiers). Although one sample dissolved transparently in both water and ethanol, other samples produced white turbidity and/or precipitates and did not meet the solubility criterion established by the Joint Food and Agriculture Organization of the United Nations (FAO)/WHO Expert Committee on Food Additives (JECFA). When the sample solutions were heated, the solubility in both water and ethanol increased. All of the samples dissolved transparently in ethanol, and dispersed and became white without producing precipitates in water. The present study suggests that the current solubility criterion of the JECFA SEFA specifications needs to be revised.

  19. Amino acids as co-amorphous stabilizers for poorly water soluble drugs--Part 1

    DEFF Research Database (Denmark)

    Löbmann, Korbinian; Grohganz, Holger; Laitinen, Riikka

    2013-01-01

    molecular weight excipients that form specific molecular interactions with the drug resulting in co-amorphous forms. The two poorly water soluble drugs carbamazepine and indomethacin were combined with amino acids from the binding sites of the biological receptors of these drugs. Mixtures of drug...

  20. Stability constants and solubility of neptunium and plutonium complexes with alkylphosphoric acids in TBP

    International Nuclear Information System (INIS)

    Fedoseev, D.A.; Romanovskaya, I.A.; Artemova, L.A.; Gubina, M.Yu.

    1988-01-01

    Stability concetration constants K and solubility of neptunium and plutonium complexes with di- and monobuthylphosphoric acids (APC) and with orthophosphoric and di-2-ethylhexyl-phosphoric acids in 30% TBP solution-n-dodecane system are determined by spectrophotometric titration and radiometry methods. Posibility of forecasting radiation-chemical behaviour of actinids according to data on K and APC radiation-chemical yield values is demonstrated

  1. Stability constants and solubility of neptunium and plutonium complexes with alkylphosphoric acids in TBP

    International Nuclear Information System (INIS)

    Fedoseev, D.A.; Romanovskaya, I.A.; Artemova, L.A.; Gibina, M.Yu.

    1989-01-01

    The concentration stability constants (K s ) and solubility of neptunium and plutonium complexes with di- and monobutylphosphoric acids (APA), as well as with orthophosphoric acid in the system composed of 30% TBP + n-dodecane, have been determined by spectrophotometric titration and radiometry. The feasibility of predicting the radiative chemical behavior of actinides based on their K s values and the radiative chemical yield of APA has been demonstrated

  2. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    Science.gov (United States)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  3. Antimicrobial and Antifungal Effects of Acid and Water-Soluble Chitosan Extracted from Indian Shrimp (Fenneropenaeus indicus Shell

    Directory of Open Access Journals (Sweden)

    Ali Taheri

    2013-06-01

    Full Text Available Background & Objective : Currently, efforts are underway to seek new and effective antimicrobial agents, and marine resources are potent candidates for this aim. The following study was conducted to investigate the efficacy of water-soluble and acid-soluble chitosan against some pathogenic organisms.   Materials & Method s: Inhibition zone of different concentrations (5, 7.5, and 10 mg/ml of acid- soluble and water-soluble chitosan were examined for in vitro antibacterial activity against 4 kinds of hospital bacteria and penicillium sp. Results were compared with 4 standard antibiotics: streptomycin, gentamicin, tetracycline, and erythromycin. Furthermore, minimum inhibitory concentration and minimum lethal concentration were determined.   Results: Inhibition activity of acid-soluble chitosan (10% showed the best result (p value < 0.05, whereas water-soluble chitosan exhibited the least antibacterial effects (p value < 0.05. Chitosan demonstrated maximum effect on V. cholera cerotype ogava , and the least effect was seen on E. coli (p value < 0.05. Acid-soluble chitosan had a more potent effect than the standard antibiotics. Also, acid-soluble chitosan (10% and water-soluble chitosan showed maximum inhibitory effects on penicillium sp.   Conclusion: Chitosan showed maximum antibacterial effect against S. aureus, V. cholerae cerotype ogava, and water-soluble chitosan demonstrated good antifungal effects, revealing a statistically significant difference with common antibacterial and antifungal medicines.

  4. PON-Sol: prediction of effects of amino acid substitutions on protein solubility.

    Science.gov (United States)

    Yang, Yang; Niroula, Abhishek; Shen, Bairong; Vihinen, Mauno

    2016-07-01

    Solubility is one of the fundamental protein properties. It is of great interest because of its relevance to protein expression. Reduced solubility and protein aggregation are also associated with many diseases. We collected from literature the largest experimentally verified solubility affecting amino acid substitution (AAS) dataset and used it to train a predictor called PON-Sol. The predictor can distinguish both solubility decreasing and increasing variants from those not affecting solubility. PON-Sol has normalized correct prediction ratio of 0.491 on cross-validation and 0.432 for independent test set. The performance of the method was compared both to solubility and aggregation predictors and found to be superior. PON-Sol can be used for the prediction of effects of disease-related substitutions, effects on heterologous recombinant protein expression and enhanced crystallizability. One application is to investigate effects of all possible AASs in a protein to aid protein engineering. PON-Sol is freely available at http://structure.bmc.lu.se/PON-Sol The training and test data are available at http://structure.bmc.lu.se/VariBench/ponsol.php mauno.vihinen@med.lu.se Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. Hydroxylamine hydrochloride-acetic acid-soluble and -insoluble fractions of pelagic sediment: Readsorption revisited

    Science.gov (United States)

    Piper, D.Z.; Wandless, G.A.

    1992-01-01

    The extraction of the rare earth elements (REE) from deep-ocean pelagic sediment, using hydroxylamine hydrochloride-acetic acid, leads to the separation of approximately 70% of the bulk REE content into the soluble fraction and 30% into the insoluble fraction. The REE pattern of the soluble fraction, i.e., the content of REE normalized to average shale on an element-by-element basis and plotted against atomic number, resembles the pattern for seawater, whereas the pattern, as well as the absolute concentrations, in the insoluble fraction resembles the North American shale composite. These results preclude significant readsorption of the REE by the insoluble phases during the leaching procedure.

  6. Poly(aspartic acid) with adjustable pH-dependent solubility.

    Science.gov (United States)

    Németh, Csaba; Gyarmati, Benjámin; Abdullin, Timur; László, Krisztina; Szilágyi, András

    2017-02-01

    Poly(aspartic acid) (PASP) derivatives with adjustable pH-dependent solubility were synthesized and characterized to establish the relationship between their structure and solubility in order to predict their applicability as a basic material for enteric coatings. Polysuccinimide, the precursor of PASP, was modified with short chain alkylamines, and the residual succinimide rings were subsequently opened to prepare the corresponding PASP derivatives. Study of the effect of the type and concentration of the side groups on the pH-dependent solubility of PASP showed that solubility can be adjusted by proper selection of the chemical structure. The Henderson-Hasselbalch (HH) and the extended HH equations were used to describe the pH-dependent solubility of the polymers quantitatively. The estimate provided by the HH equation is poor, but an accurate description of the pH-dependent solubility can be found with the extended HH equation. The dissolution rate of a polymer film prepared from a selected PASP derivative was determined by fluorescence marking. The film dissolved rapidly when the pH was increased above its pK a . Cellular viability tests show that PASP derivatives are non-toxic to a human cell line. These polymers are thus of great interest as starting materials for enteric coatings. Poly(amino acid) type biocompatible polymers were synthesized for future use as pharmaceutical film coatings. To this end, we tailored the pH-dependent solubility of poly(aspartic acid) (PASP). It was found that both the solubility and the pK a values of the modified PASP depended strongly on composition. Fluorescent marking was used to characterize the dissolution of a chosen PASP derivative. In acidic media only a negligible amount of the polymer dissolved, but dissolution was very fast and complete at the pH values that prevail in the small intestine. As a consequence, enteric coatings based on such PASP derivatives may be used for drug delivery in the gastrointestinal tract

  7. Acid-base equilibria and solubility of loratadine and desloratadine in water and micellar media.

    Science.gov (United States)

    Popović, Gordana; Cakar, Mira; Agbaba, Danica

    2009-01-15

    Acid-base equilibria in homogeneous and heterogeneous systems of two antihistaminics, loratadine and desloratadine were studied spectrophotometrically in Britton-Robinson's buffer at 25 degrees C. Acidity constant of loratadine was found to be pK(a) 5.25 and those of desloratadine pK(a1) 4.41 and pK(a2) 9.97. The values of intrinsic solubilities of loratadine and desloratadine were 8.65x10(-6) M and 3.82x10(-4) M, respectively. Based on the pK(a) values and intrinsic solubilities, solubility curves of these two drugs as a function of pH were calculated. The effects of anionic, cationic and non-ionic surfactants applied in the concentration exceeding critical micelle concentration (cmc) on acid-base properties of loratadine and desloratadine, as well as on intrinsic solubility of loratadine were also examined. The results revealed a shift of pK(a) values in micellar media comparing to the values obtained in water. These shifts (DeltapK(a)) ranged from -2.24 to +1.24.

  8. Synthesis and properties of amino acid functionalized water-soluble perylene diimides

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yongshan; Li, Xuemei; Wei, Xiaofeng; Jiang, Tianyi; Wu, Junsen; Ren, Huixue [Shandong Jianzhu University, Jinan (China)

    2015-07-15

    We prepared amino acid functionalized water-soluble perylene diimides: N,N'-bi(L-glutamic acid)-perylene-3,4;9,10-dicarboxylic diimide (1), N,N'-bi(L-phenylalanine acid)-perylene-3,4;9,10-dicarboxylic diimide (2), N,N'-bi(Lglutamic amine)-perylene-3,4;9,10-dicarboxylic diimide (3) and N,N'-bi(L-phenylalanine amine)-perylene-3,4;9,10-dicarboxylic diimide (4). The structures of 3 and 4 were confirmed by {sup 1}H NMR, FT-IR and MS. The maximal absorption bands of compound 1 and 2 in concentrated sulfuric acid were red-shifted for about 48 and 74 nm, respectively, compared with that of Perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCDA). Nearly no fluorescence was observed for compounds 1 and 2 in water, while compounds 3 and 4 were significantly water-soluble and had very high fluorescent quantum. The mechanism of the optical properties change was discussed, and the π-π stacking caused by H{sup +} led to the changes of fluorescence spectrum and absorption spectrum. The calculated molecular orbital energies and the frontier molecular orbital maps of compounds 1-2 based on density function theory (DFT) calculations were reported. Owing to the high water-soluble, the perylene derivatives 3 and 4 were successfully applied as high-performance fluorochromes for living hela cells imaging.

  9. Ionic liquid-assisted solublization for improved enzymatic esterification of phenolic acids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    2012-01-01

    in a binary system, which is composed of ionic liquid tOMA•TFA (trioctylmethylammonium Trifluoroacetate) and octanol. Ionic liquid tOMA•TFA has great solubility towards most of phenolic acid. The strategy of increasing the solubility of phenolic in ionic liquid tOMA•TFA was proved to be an efficient way...... for increasing conversion of phenolic acids. The mixture ratio between tOMA•TFA and octanol was varied from 1:4 to 1:16 (v/v), it was found that the highest conversion of dihydrocaffeic acid (DHCA) was achieved when tOMA•TFA and octanol was mixed as 1:12 (v/v). It was also found that conversion of DHCA at 70 o...

  10. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Energy Technology Data Exchange (ETDEWEB)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  11. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    International Nuclear Information System (INIS)

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad

    2015-01-01

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  12. Efficient Route to Highly Water-Soluble Aromatic Cyclic Hydroxamic Acid Ligands

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Michael; Raymond, Kenneth N.

    2008-02-06

    2-Hydroxyisoquinolin-1-one (1,2-HOIQO) is a new member of the important class of aromatic cyclic hydroxamic acid ligands which are widely used in metal sequestering applications and metal chelating therapy. The first general approach for the introduction of substituents at the aromatic ring of the chelating moiety is presented. As a useful derivative, the highly water-soluble sulfonic acid has been synthesized by an efficient route that allows general access to 1,2-HOQIO 3-carboxlic acid amides, which are the most relevant for applications.

  13. Recent Progress in the Development of Supercritical Carbon Dioxide-Soluble Metal Ion Extractants: Aggregation, Extraction, and Solubility Properties of Silicon-Substituted Alkylenediphosphonic Acids

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Mark L.; McAlister, Daniel R.; Stepinski, Dominique C.; Zalupski, Peter R.; Dzilawa, Julie A.; Barrans, Richard E.; Hess, J.N.; Rubas, Audris V.; Chiarizia, Renato; Lubbers, Christopher M.; Scurto, Aaron M.; Brennecke, Joan F.; Herlinger, Albert W.

    2003-09-11

    Partially esterified alkylenediphosphonic acids (DPAs) have been shown to be effective reagents for the extraction of actinide ions from acidic aqueous solution into conventional organic solvents. Efforts to employ these compounds in supercritical fluid extraction have been hampered by their modest solubility in unmodified supercritical carbon dioxide (SC-CO2). In an effort to design DPAs that are soluble in SC-CO2, a variety of silicon-substituted alkylenediphosphonic acids have been prepared and characterized, and their behavior compared with that of conventional alkyl-substituted reagents. Silicon substitution is shown to enhance the CO2-philicity of the reagents, while other structural features, in particular, the number of methylene groups bridging the phosphorus atoms of the extractant, are shown to exert a significant influence on their aggregation and extraction properties. The identification of DPAs combining desirable extraction properties with adequate solubility in SC-CO2 is shown to be facilitated by the application of molecular connectivity indices.

  14. Effects of roasting temperatures and gamma irradiation on the content of chlorogenic acid, caffeic acid and soluble carbohydrates of coffee

    International Nuclear Information System (INIS)

    Deshpande, S.N.; Aguilar, A.A.

    1975-01-01

    Two varieties of Puerto Rican coffee, Coffea canephora L. var. Robusta, and Coffea arabica L. var. Borbon, were subjected to four different doses of radiation and roasted at two different temperatures. Aqueous extracts of the ground coffee beans were analyzed for chlorogenic acid and caffeic acid at 324 nm and 360 nm wavelength settings, respectively. Samples subjected to the roasting treatments in conjuction with irradiation treatments were treated with basic lead acetate prior to the colorimetric analyses in order to eliminate interfering substances. The total carbohydrate content was also determined by colorimetric techniques with anthrone reagent. The total nitrogen content of the pulverized samples were determined by the micro-Kjeldahl method. While roasting treatments caused a reduction in the concentrations of the chlorogenic acid, caffeic acid, and the carbohydrates, the radiation treatments increased the concentrations of soluble carbohydrates without affecting the concentrations of chlorogenic acid or caffeic acid. It therefore appears that radiation treatments seem to cause degradation of the acid-polysaccharide complexes liberating soluble sugars. There were no noticable changes in the total content of nitrogen caused by roasting or the radiation treatments as indicated by the statistical analysis employing the split plot design. (author)

  15. Characterization of a soluble phosphatidic acid phosphatase in bitter melon (Momordica charantia).

    Science.gov (United States)

    Cao, Heping; Sethumadhavan, Kandan; Grimm, Casey C; Ullah, Abul H J

    2014-01-01

    Momordica charantia is often called bitter melon, bitter gourd or bitter squash because its fruit has a bitter taste. The fruit has been widely used as vegetable and herbal medicine. Alpha-eleostearic acid is the major fatty acid in the seeds, but little is known about its biosynthesis. As an initial step towards understanding the biochemical mechanism of fatty acid accumulation in bitter melon seeds, this study focused on a soluble phosphatidic acid phosphatase (PAP, 3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4) that hydrolyzes the phosphomonoester bond in phosphatidate yielding diacylglycerol and P(i). PAPs are typically categorized into two subfamilies: Mg(2+)-dependent soluble PAP and Mg(2+)-independent membrane-associated PAP. We report here the partial purification and characterization of an Mg(2+)-independent PAP activity from developing cotyledons of bitter melon. PAP protein was partially purified by successive centrifugation and UNOsphere Q and S columns from the soluble extract. PAP activity was optimized at pH 6.5 and 53-60 °C and unaffected by up to 0.3 mM MgCl2. The K(m) and Vmax values for dioleoyl-phosphatidic acid were 595.4 µM and 104.9 ηkat/mg of protein, respectively. PAP activity was inhibited by NaF, Na(3)VO(4), Triton X-100, FeSO4 and CuSO4, but stimulated by MnSO4, ZnSO4 and Co(NO3)2. In-gel activity assay and mass spectrometry showed that PAP activity was copurified with a number of other proteins. This study suggests that PAP protein is probably associated with other proteins in bitter melon seeds and that a new class of PAP exists as a soluble and Mg(2+)-independent enzyme in plants.

  16. Chasing equilibrium: measuring the intrinsic solubility of weak acids and bases.

    Science.gov (United States)

    Stuart, Martin; Box, Karl

    2005-02-15

    A novel procedure is described for rapid (20-80 min) measurement of intrinsic solubility values of organic acids, bases, and ampholytes. In this procedure, a quantity of substance was first dissolved at a pH where it exists predominantly in its ionized form, and then a precipitate of the neutral (un-ionized) species was formed by changing the pH. Subsequently, the rate of change of pH due to precipitation or dissolution was monitored and strong acid and base titrant were added to adjust the pH to discover its equilibrium conditions, and the intrinsic solubility of the neutral form of the compound could then be determined. The procedure was applied to a variety of monoprotic and diprotic pharmaceutical compounds. The results were highly repeatable and had a good correlation to available published values. Data collected during the procedure provided good diagnostic information. Kinetic solubility data were also collected but provided a poor guide to the intrinsic solubility.

  17. The "high solubility" definition of the current FDA Guidance on Biopharmaceutical Classification System may be too strict for acidic drugs.

    Science.gov (United States)

    Yazdanian, Mehran; Briggs, Katherine; Jankovsky, Corinne; Hawi, Amale

    2004-02-01

    The purpose of this study was to assess if the definition of high solubility as proposed in the FDA Guidance on Biopharmaceutical Classification System (BCS) is too strict for highly permeable acidic drugs. The solubility and permeability values of 20 (18 acidic and 2 non-acidic) nonsteroidal anti-inflammatory drugs (NSAID) were determined. The NSAIDs were grouped into three different sets having acetic acid, propionic acid, or other acidic moieties such as fenamate, oxicam, and salicylate. Two nonacidic NSAIDs (celecoxib and rofecoxib) were also included for comparison purposes. Equilibrium solubility values were determined at pH 1.2, 5.0, 7.4, and in biorelevant media simulating fed intestinal fluid at pH 5.0. For a select number of acids, we also measured solubility values in media simulating gastric and fasted intestinal fluids. Permeability classification was established relative to that of reference drugs in the Caco-2 cell permeability model. Permeability coefficients for all drugs were measured at concentrations corresponding to the lowest and highest marketed dose strengths dissolved in 250 ml volume, and their potential interaction with cellular efflux pumps was investigated. All NSAIDs with different acidic functional groups were classified as highly permeable based on their Caco-2 cell permeability. Only ketorolac appeared to have a potential for interaction with cellular efflux pumps. Solubility classification was based on comparison of equilibrium solubility at pH 1.2, 5.0. and 7.4 relative to marketed dose strengths in 250 ml. The pKa values for the acidic NSAIDs studied were between 3.5 and 5.1. and, as expected, their solubility increased dramatically at pH 7.4 compared to pH 1.2. Only three NSAIDs, ketorolac, ketoprofen. and acetyl salicylic acid, meet the current criteria for high solubility over the entire pH range. However, with the exception of ibuprofen, oxaprozin, and mefenamic acid, the remaining compounds can be classified as Class I drugs

  18. Lysophosphatidic acids are new substrates for the phosphatase domain of soluble epoxide hydrolase[S

    OpenAIRE

    Oguro, Ami; Imaoka, Susumu

    2012-01-01

    Soluble epoxide hydrolase (sEH) is a bifunctional enzyme that has a C-terminus epoxide hydrolase domain and an N-terminus phosphatase domain. The endogenous substrates of epoxide hydrolase are known to be epoxyeicosatrienoic acids, but the endogenous substrates of the phosphatase activity are not well understood. In this study, to explore the substrates of sEH, we investigated the inhibition of the phosphatase activity of sEH toward 4-methylumbelliferyl phosphate by using lecithin and its hyd...

  19. Characterization of Acid Soluble Collagen from Redbelly Yellowtail Fusilier Fish Skin (Caesio cuning

    Directory of Open Access Journals (Sweden)

    Ika Astiana

    2016-04-01

    Full Text Available Fish skin can be used as raw material for producing collagen. The collagen can be extracted by chemical or combination of chemical and enzymatic processes. Extraction of collagen chemically can do with the acid process that produces acid soluble collagen (ASC. This study aimed to determine the optimum concentration and time of pretreatment and extraction, also to determine the characteristics of the acid soluble collagen from the skin of yellow tail fish. Extraction of collagen done by pretreatment using NaOH at the concentration of 0.05; 0.1; and 0.15 M and extraction using acetic acid at the concentration of 0.3; 0.5; and 0.7 M. Pretreatment NaOH with concentration 0.05 M and soaking time of 8 hours is the best combination for eliminating non collagen protein. Combination treatment of acetic acid at the concentration of 0.3 M for 3 days obtained the best solubility. The yield of collagen ASC was 18.4±1.49% (db and 5.79±0.47% (wb. Amino acid composition that is dominant in the ASC collagen was glycine (25.09±0.003%, alanine (13.71±0.075%, and proline (12.15±0.132%. Collagen from yellow tail fish skin has α1, α2, β and γ protein structure with the molecular weight of 125, 113, 170-181, and 208 KDa. The transition and melting temperatures of collagen were 67.69oC and 144.4oC. The surface structure of collagen by analysis of SEM has fibers on the surface.

  20. Improving the water solubility of Monascus pigments under acidic conditions with gum arabic.

    Science.gov (United States)

    Jian, Wenjie; Sun, Yuanming; Wu, Jian-Yong

    2017-07-01

    Monascus pigments (Mps) are natural food colorants and their stability in acidic solutions is important for application in the food industry. This study aimed to evaluate the use of gum arabic (GA) as a stabilizer for maintaining the solubility of Mps in an acidic aqueous solution exposed to a high temperature, and to analyze the molecular interactions between GA and Mps. Mps dispersed (0.2 g kg -1 ) in deionized water at pH 3.0-4.0 without GA formed precipitates but remained in a stable solution in the presence of GA (1 g kg -1 ). The significant improvement of Mps water solubility under acidic conditions was attributed to the formation of Mps-GA complexes, as indicated by a sharp increase in the fluorescence intensity. The results on particle size, zeta potential, and transmission electron microscopy further suggested that molecular binding of Mps to GA, electrostatic repulsion, and steric hindrance of GA were contributing factors to preventing the aggregation of Mps in acidic solutions. A mechanistic model was presented for GA-Mps interactions and complex structures. GA was proven to be an effective stabilizer of natural food colorants in acidic solutions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Synthesis, structural, solubility and anticancer activity studies of salts using nucleobases and sulfonic acids coformer

    Science.gov (United States)

    Singh, Neetu; Singh, Udai P.; Nikhil, Kumar; Roy, Partha; Singh, Hariji

    2017-10-01

    The reactions of natural and unnatural nucleobases (cytosine (Cyt), adenine (Ade), 5-aminouracil (AU) and caffeine (Caff)) with sulfonic acids coformer (1,5-naphthalenedisulfonic acid, NDSA; 5-sulfosalicylic acid, SSA) resulted in the formation of salts viz. [NDSA.Cyt] (1), [NDSA.Ade] (2), [NDSA.AU] (3), [NDSA.Caff] (4), [SSA.Cyt] (5), [SSA.Ade] (6), [SSA.AU] (7), and [SSA.Caff] (8). The structural analysis revealed that salts 1, 4, 6 and 7 have intermolecular interactions between adjacent nucleobases which form two different homodimer shown in R22 (8) motif and assembled via complementary Nsbnd H⋯O and Nsbnd H⋯N interactions. However, in all other salts an intermediate supramolecular synthon pattern was observed between nucleobases and sulfonic acids. The lattice energy was also calculated by DFT to investigate whether salts were thermodynamically more stable than its coformer. The same was further confirmed by differential scanning calorimetry-thermogravimetric (DSC-TG) analysis. The anticancer activity study of individual nucleobases and their NDSA salts were also performed on human breast (MCF-7) and lung (A 549) cancer cell. The salts formation of nucleobases with sulfonic acids improved their solubility, thereby demonstrating up to 8-fold increase in solubility of nucleobases.

  2. On solubility of perchloric (periodic) acid and α-cyanacetanmide in aqueous solutions at 25 deg C

    International Nuclear Information System (INIS)

    Omarova, R.A.; Balysbekov, S.M.; Erkasov, R.Sh.; Nikolenko, O.N.

    1996-01-01

    Acid-base interaction within perchloric (periodic) acid-α-cyanacetamide-water systems in studied by method of solubility under isothermal conditions at 25 deg C. Solubility regularities of crystalline α-cyanacetamide in perchloric and periodic acid solutions are determined, the concentration limits of formation of a new solid phase-tris(α-cyanacetamide) perchlorate within perchloric acid-α-cyanacetamide-water system are determined. The compound is identified by means of chemical and X-ray phase analyses, its density and melting temperature are determined. Iodic acid and α-cyanacetamide water solution base system is shown to belong to a simple eutonic type. 2 refs., 3 figs., 2 tabs

  3. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Science.gov (United States)

    Jing, Bo; Wang, Zhen; Tan, Fang; Guo, Yucong; Tong, Shengrui; Wang, Weigang; Zhang, Yunhong; Ge, Maofa

    2018-04-01

    While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO3)2) and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA). The nitrate salt / organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH), the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  4. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Directory of Open Access Journals (Sweden)

    B. Jing

    2018-04-01

    Full Text Available While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO32 and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA. The nitrate salt ∕ organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH, the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  5. Drug-drug cocrystals of antituberculous 4-aminosalicylic acid: Screening, crystal structures, thermochemical and solubility studies.

    Science.gov (United States)

    Drozd, Ksenia V; Manin, Alex N; Churakov, Andrei V; Perlovich, German L

    2017-03-01

    Experimental multistage cocrystal screening of the antituberculous drug 4-aminosalicylic acid (PASA) has been conducted with a number of coformers (pyrazinamide (PYR), nicotinamide (NAM), isonicotinamide (iNAM), isoniazid (INH), caffeine (CAF) and theophylline (TPH)). The crystal structures of 4-aminosalicylic acid cocrystals with isonicotinamide ([PASA+iNAM] (2:1)) and methanol solvate with caffeine ([PASA+CAF+MeOH] (1:1:1)) have been determined by single X-ray diffraction experiments. For the first time for PASA cocrystals it has been found that the structural unit of the [PASA+iNAM] cocrystal (2:1) is formed by 2 types of heterosynthons: acid-pyridine and acid-amide. The desolvation study of the [PASA+CAF+MeOH] cocrystal solvate (1:1:1) has been conducted. The correlation models linking the melting points of the cocrystals with the melting points of the coformers used in this paper have been developed. The thermochemical and solubility properties for all the obtained cocrystals have been studied. Cocrystallization has been shown to lead not only to PASA solubility improving but also to its higher stability against the chemical decomposition. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Chemical constituents: water-soluble vitamins, free amino acids and sugar profile from Ganoderma adspersum.

    Science.gov (United States)

    Kıvrak, İbrahim

    2015-01-01

    Ganoderma adspersum presents a rigid fruiting body owing to chitin content and having a small quantity of water or moisture. The utility of bioactive constituent of the mushroom can only be available by extraction for human usage. In this study, carbohydrate, water-soluble vitamin compositions and amino acid contents were determined in G. adspersum mushroom. The composition in individual sugars was determined by HPLC-RID, mannitol (13.04 g/100 g) and trehalose (10.27 g/100 g) being the most abundant sugars. The examination of water-soluble vitamins and free amino acid composition was determined by UPLC-ESI-MS/MS. Essential amino acid constituted 67.79% of total amino acid, which is well worth the attention with regard to researchers and consumers. In addition, G. adspersum, which is also significantly rich in B group vitamins and vitamin C, can provide a wide range of notable applications in the pharmaceutics, cosmetics, food and dietary supplement industries. G. adspersum revealed its value for pharmacy and nutrition fields.

  7. Threshold value of enamel mineral solubility and dental erosion after consuming acidic soft drinks

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2011-09-01

    Full Text Available Background: Dental erosion is irreversible and can caused by acidic soft drink consumption. Dental erosion prevention had already been done, but it still has not been satisfying since the consumption of acidic soft drink is still high. There is still no explanation about the threshold value of enamel mineral solubility and the occurance of dental erosion after consuming acidic soft drink. Purpose: This research is aimed to find the threshold value of enamel mineral solubility and dental erosion before and after consuming acidic soft drinks. Methods: Subjects of the research are saliva and enamel of 12 rabbits, which have some criteria such as age > 70 days, body weight > 600 grams, and teeth considered to be healthy. The sample devided equally into 4 groups. Each of those marmooths was given a drink as much as 2.5 cc/consumption (there are 1, 2 and 3× per day by using syringe without injection needle. Salivary minerals then were examined by using atomic absorption spectrophotometric (ASS, while dental erosion was examined using scanning electron microscop (SEM. The data were analyzed by using Paired t-test. Results: It is known that the threshold value of enamel mineral solubility (K, Na, Fe, Mg, Cl, P, Ca, F, C has significant difference (p < 0.05 after being exposed to folic acid. Meanwhile, Fe did not have significant difference (p = 0.090 after being exposed to citric acid. Similarly, C did not have significant difference (p = 0.063 after being exposed to bicarbonate acid. Furthermore, it is also known that the threshold time value of dental erosion are on the 105th day for folic acid, on the 111th day for citric acid, and on the 117th day for bicarbonate acid. Conclusion: Threshold value of enamel mineral solubility before and after consuming soft drinks containing acid is different. Based on the threshold value of dental erosion, it is known that folic acid is the most erosive acid.Latar belakang: Erosi gigi bersifat irreversible

  8. Lysophosphatidic acids are new substrates for the phosphatase domain of soluble epoxide hydrolase[S

    Science.gov (United States)

    Oguro, Ami; Imaoka, Susumu

    2012-01-01

    Soluble epoxide hydrolase (sEH) is a bifunctional enzyme that has a C-terminus epoxide hydrolase domain and an N-terminus phosphatase domain. The endogenous substrates of epoxide hydrolase are known to be epoxyeicosatrienoic acids, but the endogenous substrates of the phosphatase activity are not well understood. In this study, to explore the substrates of sEH, we investigated the inhibition of the phosphatase activity of sEH toward 4-methylumbelliferyl phosphate by using lecithin and its hydrolyzed products. Although lecithin itself did not inhibit the phosphatase activity, the hydrolyzed lecithin significantly inhibited it, suggesting that lysophospholipid or fatty acid can inhibit it. Next, we investigated the inhibition of phosphatase activity by lysophosphatidyl choline, palmitoyl lysophosphatidic acid, monopalmitoyl glycerol, and palmitic acid. Palmitoyl lysophosphatidic acid and fatty acid efficiently inhibited phosphatase activity, suggesting that lysophosphatidic acids (LPAs) are substrates for the phosphatase activity of sEH. As expected, palmitoyl, stearoyl, oleoyl, and arachidonoyl LPAs were efficiently dephosphorylated by sEH (Km, 3–7 μM; Vmax, 150–193 nmol/min/mg). These results suggest that LPAs are substrates of sEH, which may regulate physiological functions of cells via their metabolism. PMID:22217705

  9. Lysophosphatidic acids are new substrates for the phosphatase domain of soluble epoxide hydrolase.

    Science.gov (United States)

    Oguro, Ami; Imaoka, Susumu

    2012-03-01

    Soluble epoxide hydrolase (sEH) is a bifunctional enzyme that has a C-terminus epoxide hydrolase domain and an N-terminus phosphatase domain. The endogenous substrates of epoxide hydrolase are known to be epoxyeicosatrienoic acids, but the endogenous substrates of the phosphatase activity are not well understood. In this study, to explore the substrates of sEH, we investigated the inhibition of the phosphatase activity of sEH toward 4-methylumbelliferyl phosphate by using lecithin and its hydrolyzed products. Although lecithin itself did not inhibit the phosphatase activity, the hydrolyzed lecithin significantly inhibited it, suggesting that lysophospholipid or fatty acid can inhibit it. Next, we investigated the inhibition of phosphatase activity by lysophosphatidyl choline, palmitoyl lysophosphatidic acid, monopalmitoyl glycerol, and palmitic acid. Palmitoyl lysophosphatidic acid and fatty acid efficiently inhibited phosphatase activity, suggesting that lysophosphatidic acids (LPAs) are substrates for the phosphatase activity of sEH. As expected, palmitoyl, stearoyl, oleoyl, and arachidonoyl LPAs were efficiently dephosphorylated by sEH (Km, 3-7 μM; Vmax, 150-193 nmol/min/mg). These results suggest that LPAs are substrates of sEH, which may regulate physiological functions of cells via their metabolism.

  10. Cytotoxicity of alkylating agents towards sensitive and resistant strains of Escherichia coli in relation to extent and mode of alkylation of cellular macromolecules and repair of alkylation lesions in deoxyribonucleic acids.

    Science.gov (United States)

    Lawley, P D; Brookes, P

    1968-09-01

    . Effects of the sulphur mustards on nucleic acid synthesis in sensitive and resistant strains were studied. DNA synthesis was inhibited in both strains at low doses in a dose-dependent manner, but RNA and protein synthesis were not affected in this way. 9. DNA synthesis in E. coli B(s-1) was permanently inhibited by low doses of mustards. In the resistant strains 15T(-) and B/r a characteristic recovery in DNA synthesis was observed after a dose-dependent time-lag. This effect could be shown at low doses in the region of the mean lethal dose. 10. Cellular DNA was isotopically prelabelled and the effect of mustards on stability of DNA was investigated. With resistant strains a dose-dependent release of DNA nucleotide material into acid-soluble form was found; this was much more extensive with the difunctional mustard (about 400 nucleotides released per DNA alkylation) than with the monofunctional mustard (about 10 nucleotides per alkylation). With the sensitive strain no dose-dependent release was found, though the DNA was less stable independent of cellular alkylation. 11. The results are discussed in terms of the concepts that alkylation of cellular DNA induces lesions which interfere with DNA replication, but which can be enzymically ;repaired'. The possible nature of these lesions is discussed in terms of the known reactions of the alkylating agents with DNA.

  11. Characterization of Acid Soluble Collagen from Redbelly Yellowtail Fusilier Fish Skin (Caesio cuning

    Directory of Open Access Journals (Sweden)

    Ika Astiana

    2016-04-01

    Full Text Available Fish skin can be used as raw material for producing collagen. The collagen can be extracted by chemicalor combination of chemical and enzymatic processes. Extraction of collagen chemically can do with theacid process that produces acid soluble collagen (ASC. This study aimed to determine the optimumconcentration and time of pretreatment and extraction, also to determine the characteristics of the acidsoluble collagen from the skin of yellow tail fish. Extraction of collagen done by pretreatment using NaOH atthe concentration of 0.05; 0.1; and 0.15 M and extraction using acetic acid at the concentration of 0.3; 0.5; and0.7 M. Pretreatment NaOH with concentration 0.05 M and soaking time of 8 hours is the best combinationfor eliminating non collagen protein. Combination treatment of acetic acid at the concentration of 0.3 Mfor 3 days obtained the best solubility. The yield of collagen ASC was 18.4±1.49% (db and 5.79±0.47%(wb. Amino acid composition that is dominant in the ASC collagen was glycine (25.09±0.003%, alanine(13.71±0.075%, and proline (12.15±0.132%. Collagen from yellow tail fish skin has α1, α2, β and γprotein structure with the molecular weight of 125, 113, 170-181, and 208 KDa. The transition and meltingtemperatures of collagen were 67.69oC and 144.4oC. The surface structure of collagen by analysis of SEM hasfibers on the surface.Keywords: cholesterol, fatty acids, meat tissue, proximate, red snapper (L. argentimaculatus

  12. Microwave-induced facile synthesis of water-soluble fluorogenic alginic acid derivatives.

    Science.gov (United States)

    Chhatbar, Mahesh U; Meena, Ramavatar; Prasad, Kamalesh; Chejara, Dharmesh R; Siddhanta, A K

    2011-04-01

    A facile microwave-induced method was developed for synthesizing water-soluble fluorescent derivatives of alginic acid (ALG) with four different diamines, hydrazine (HY), ethylenediamine (EDA), 1,6-hexanediamine (HDA), and 1,4-cyclohexanediamine (CHDA), followed by a cross-linking reaction with a natural cross linker genipin. The ethylenediamine derivative of alginic acid (ALG-EDA) exhibited good fluorescent activity, which upon cross linking was enhanced threefold. The other amide derivatives, for example, ALG-HY, ALG-HDA, and ALG-CHDA, were not fluorescent, but their respective crosslinked products exhibited excellent fluorescent activity. The fluorescence intensity had an inverse correlation with the number of carbon atoms present in the amine, which in turn was a function of degree of substitution (DS). These fluorescent polysaccharide derivatives are of potential utility in the domain of sensor applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. In vitro oxidation of indoleacetic acid by soluble auxin-oxidases and peroxidases from maize roots

    International Nuclear Information System (INIS)

    Beffa, R.; Martin, H.V.; Pilet, P.E.

    1990-01-01

    Soluble auxin-oxidases were extracted from Zea mays L. cv LG11 apical root segments and partially separated from peroxidases (EC 1.11.1.7) by size-exclusion chromatography. Auxin-oxidases were resolved into one main peak corresponding to a molecular mass of 32.5 kilodaltons and a minor peak at 54.5 kilodaltons. Peroxidases were separated into at least four peaks, with molecular masses from 32.5 to 78 kilodaltons. In vitro activity of indoleacetic acid-oxidases was dependent on the presence of MnCl 2 and p-coumaric acid. Compound(s) present in the crude extract and several synthetic auxin transport inhibitors (including 2,3,5-triiodobenzoic acid and N-1-naphthylphthalamic acid) inhibited auxin-oxidase activity, but had no effect on peroxidases. The products resulting from the in vitro enzymatic oxidation of [ 3 H]indoleacetic acid were separated by HPLC and the major metabolite was found to cochromatograph with indol-3yl-methanol

  14. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    International Nuclear Information System (INIS)

    Makarska-Bialokoz, Magdalena; Borowski, Piotr

    2015-01-01

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H 2 TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10 5 mol −1 . The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H 2 TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated

  15. Fluorescence quenching behaviour of uric acid interacting with water-soluble cationic porphyrin

    Energy Technology Data Exchange (ETDEWEB)

    Makarska-Bialokoz, Magdalena, E-mail: makarska@hektor.umcs.lublin.pl [Department of Inorganic Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 2, 20-031 Lublin (Poland); Borowski, Piotr [Faculty of Chemistry, Maria Curie-Sklodowska University M. C. Sklodowska Sq. 3, 20-031 Lublin (Poland)

    2015-04-15

    The process of association between 5,10,15,20-tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine tetra-p-tosylate (H{sub 2}TTMePP) and uric acid as well as its sodium salt has been studied in aqueous NaOH solution analysing its absorption and steady-state fluorescence spectra. The fluorescence quenching effect observed during interactions porphyrin-uric acid compounds points at the fractional accessibility of the fluorophore for the quencher. The association and fluorescence quenching constants are of the order of magnitude of 10{sup 5} mol{sup −1}. The fluorescence lifetimes and the quantum yields of the porphyrin anionic form were established. The results demonstrate that uric acid and its sodium salt can interact with H{sub 2}TTMePP at basic pH and through formation of stacking complexes are able to quench its ability to emission. - Highlights: • Association study of water soluble cationic porphyrin with uric acid. • Porphyrin absorption spectra undergo the bathochromic and hypochromic effects. • Uric acid interacts with porphyrin in inhibiting manner, quenching its emission. • Fluorescence quenching effect testifies for the partial inactivation of a porphyrin. • The association and fluorescence quenching constants were calculated.

  16. Effects of excess pantothenic acid administration on the other water-soluble vitamin metabolisms in rats.

    Science.gov (United States)

    Shibata, Katsumi; Takahashi, Chisato; Fukuwatari, Tsutomu; Sasaki, Ryuzo

    2005-12-01

    To acquire the data concerning the tolerable upper intake level which prevents health problems from an excessive intake of pantothenic acid, an animal experiment was done. Rats of the Wistar strain (male, 3 wk old) were fed on a diet which contains 0%, 0.0016% (control group), 1%, or 3% calcium pantothenate for 29 d. The amount of weight increase, the food intake, and the organ weights were measured, as well as the pantothenic acid contents in urine, the liver and blood. Moreover, to learn the influence of excessive pantothenic acid on other water-soluble vitamin metabolism, thiamin, riboflavin, a vitamin B6 catabolite, the niacin catabolites, and ascorbic acid in urine were measured. As for the 3% addition group, enlargement of the testis, diarrhea, and hair damage were observed, and the amount of weight increase and the food intake were less than those of the control group. However, abnormality was not seen in the 1% addition group. The amount of pantothenic acid in urine, the liver, and blood showed a high correlation with intake level of pantothenic acid. It was only for 4-pyridoxic acid, a vitamin B6 catabolite, in urine that a remarkable difference was observed against the control group. Moreover, the (2-Py+4-Py)/MNA excretion ratio for these metabolites of the nicotinamide also indicated a low value in the 3% pantothenic acid group. As for the calcium pantothenate, it was found that the 3% level in the diet was the lowest-observed-adverse-effect-level (LOAEL) and the 1% level was the no-observed-adverse-effect-level (NOAEL).

  17. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    Energy Technology Data Exchange (ETDEWEB)

    Khoza, Phindile; Antunes, Edith [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa); Chen, Ji-Yao [State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433 (China); Nyokong, Tebello, E-mail: t.nyokong@ru.ac.za [Department of Chemistry, Rhodes University, PO Box 94, Grahamstown (South Africa)

    2013-02-15

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by {sup 1}H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: Black-Right-Pointing-Pointer A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. Black-Right-Pointing-Pointer The conjugate is water soluble even though the phthalocyanine alone is not. Black-Right-Pointing-Pointer The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. Black-Right-Pointing-Pointer Triplet quantum yields decreased for the conjugate.

  18. Solubility-pH profiles of some acidic, basic and amphoteric drugs.

    Science.gov (United States)

    Shoghi, Elham; Fuguet, Elisabet; Bosch, Elisabeth; Ràfols, Clara

    2013-01-23

    The solubility vs. pH profiles of five ionizable drugs of different nature (a monoprotic acid, a monoprotic base, a diprotic base and two amphoteric compounds showing a zwitterionic species each one) have been determined through two different methodologies: the classical shake-flask (S-F) and the potentiometric Cheqsol methods using in both instances the appropriate Henderson-Hasselbalch (H-H) or derived relationships. The results obtained independently from both approaches are consistent. A critical revision about the influence of the electrolyte used as buffering agent in the S-F method on the obtained solubility values is also performed. Thus, some deviations of the experimental points with respect the H-H profiles can be attributed to specific interactions between the buffering electrolyte and the drug due to the hydrotrophic character of citric and lactic acids. In other cases, the observed deviations are independent of the buffers used since they are caused by the formation of new species such as drug aggregates (cefadroxil) or the precipitation of a salt from a cationic species of the analyzed compound (quetiapine). Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Effect of enzymatic treatment of extracted sunflower proteins on solubility, amino acid composition, and surface activity.

    Science.gov (United States)

    Conde, José Miñones; Escobar, María del Mar Yust; Pedroche Jiménez, Justo J; Rodríguez, Francisco Millán; Rodríguez Patino, Juan M

    2005-10-05

    Industrial proteins from agriculture of either animal or vegetable origin, including their peptide derivatives, are of great importance, from the qualitative and quantitative point of view, in food formulations (emulsions and foams). A fundamental understanding of the physical, chemical, and functional properties of these proteins is essential if the performance of proteins in foods is to be improved and if underutilized proteins, such as plant proteins (and their hydrolysates and peptides derivatives), are to be increasingly used in traditional and new processed food products (safe, high-quality, health foods with good nutritional value). In this contribution we have determined the main physicochemical characteristics (solubility, composition, and analysis of amino acids) of a sunflower protein isolate (SPI) and its hydrolysates with low (5.62%), medium (23.5%), and high (46.3%) degrees of hydrolysis. The hydrolysates were obtained by enzymatic treatment with Alcalase 2.4 L for DH 5.62 and 23.5% and with Alcalase 2.4 L and Flavorzyme 1000 MG sequentially for DH 46.3%. The protein concentration dependence on surface pressure (surface pressure isotherm), a measure of the surface activity of the products (SPI and its hydrolysates), was obtained by tensiometry. We have observed that the degree of hydrolysis has an effect on solubility, composition, and content of the amino acids of the SPI and its hydrolysates. The superficial activity and the adsorption efficiency were also affected by the degree of hydrolysis.

  20. Synthesis and photophysicochemical studies of a water soluble conjugate between folic acid and zinc tetraaminophthalocyanine

    International Nuclear Information System (INIS)

    Khoza, Phindile; Antunes, Edith; Chen, Ji-Yao; Nyokong, Tebello

    2013-01-01

    This work reports on the synthesis of zinc tetraaminophthalocyanine (ZnTAPc) functionalized with folic acid (FA), forming ZnTAPcFA. The conjugate between FA and ZnTAPc was soluble in water whereas ZnTAPc alone is not. The structure of ZnTAPcFA conjugate was elucidated by 1 H NMR, MALDI-TOF mass and FTIR spectra. Photophysical and photochemical studies of ZnTAPcFA were conducted in DMSO. The increase in fluorescence quantum yield of the conjugate was accompanied by a decrease in the triplet and singlet oxygen quantum yields. The changes in triplet quantum and singlet oxygen quantum yields were marginal when ZnTAPc was simply mixed with FA without a chemical bond. - Highlights: ► A conjugate between folic acid and a zinc tetraaminophthalocyanine was formed. ► The conjugate is water soluble even though the phthalocyanine alone is not. ► The fluorescence quantum yield of the conjugate was enhanced compared to the phthalocyanine alone. ► Triplet quantum yields decreased for the conjugate

  1. pH-metric solubility. 2: correlation between the acid-base titration and the saturation shake-flask solubility-pH methods.

    Science.gov (United States)

    Avdeef, A; Berger, C M; Brownell, C

    2000-01-01

    The objective of this study was to compare the results of a normal saturation shake-flask method to a new potentiometric acid-base titration method for determining the intrinsic solubility and the solubility-pH profiles of ionizable molecules, and to report the solubility constants determined by the latter technique. The solubility-pH profiles of twelve generic drugs (atenolol, diclofenac.Na, famotidine, flurbiprofen, furosemide, hydrochlorothiazide, ibuprofen, ketoprofen, labetolol.HCl, naproxen, phenytoin, and propranolol.HCl), with solubilities spanning over six orders of magnitude, were determined both by the new pH-metric method and by a traditional approach (24 hr shaking of saturated solutions, followed by filtration, then HPLC assaying with UV detection). The 212 separate saturation shake-flask solubility measurements and those derived from 65 potentiometric titrations agreed well. The analysis produced the correlation equation: log(1/S)titration = -0.063(+/- 0.032) + 1.025(+/- 0.011) log(1/S)shake-flask, s = 0.20, r2 = 0.978. The potentiometrically-derived intrinsic solubilities of the drugs were: atenolol 13.5 mg/mL, diclofenac.Na 0.82 microg/mL, famotidine 1.1 mg/ mL, flurbiprofen 10.6 microg/mL, furosemide 5.9 microg/mL, hydrochlorothiazide 0.70 mg/mL, ibuprofen 49 microg/mL, ketoprofen 118 microg/mL, labetolol.HCl 128 microg/mL, naproxen 14 microg/mL, phenytoin 19 microg/mL, and propranolol.HCl 70 microg/mL. The new potentiometric method was shown to be reliable for determining the solubility-pH profiles of uncharged ionizable drug substances. Its speed compared to conventional equilibrium measurements, its sound theoretical basis, its ability to generate the full solubility-pH profile from a single titration, and its dynamic range (currently estimated to be seven orders of magnitude) make the new pH-metric method an attractive addition to traditional approaches used by preformulation and development scientists. It may be useful even to discovery

  2. Improving co-amorphous drug formulations by the addition of the highly water soluble amino acid proline

    DEFF Research Database (Denmark)

    Jensen, Katrine Birgitte Tarp; Löbmann, Korbinian; Rades, Thomas

    2014-01-01

    Co-amorphous drug amino acid mixtures were previously shown to be a promising approach to create physically stable amorphous systems with the improved dissolution properties of poorly water-soluble drugs. The aim of this work was to expand the co-amorphous drug amino acid mixture approach...... by combining the model drug, naproxen (NAP), with an amino acid to physically stabilize the co-amorphous system (tryptophan, TRP, or arginine, ARG) and a second highly soluble amino acid (proline, PRO) for an additional improvement of the dissolution rate. Co-amorphous drug-amino acid blends were prepared...... the molecular interactions in the form of hydrogen bonds between all three components in the mixture. A salt formation between the acidic drug, NAP, and the basic amino acid, ARG, was found in co-amorphous NAP–ARG. In comparison to crystalline NAP, binary NAP–TRP and NAP–ARG, it could be shown that the highly...

  3. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Directory of Open Access Journals (Sweden)

    Lei Gao

    Full Text Available Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL 'SW' (in the '203Z' background were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy, sucrose-phosphate synthase (SPSs, insoluble acid invertases (IAI, NAD-dependent malate dehydrogenase (NAD-cyt MDH, aluminum-activated malate transporter (ALMT, and citrate synthase (CS. This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  4. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling; Liu, Wenge

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL) 'SW' (in the '203Z' background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  5. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar ‘203Z’ and its near-isogenic line (NIL) ‘SW’ (in the ‘203Z’ background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening. PMID:29324867

  6. Fermentable soluble fibres spare amino acids in healthy dogs fed a low-protein diet.

    Science.gov (United States)

    Wambacq, Wendy; Rybachuk, Galena; Jeusette, Isabelle; Rochus, Kristel; Wuyts, Brigitte; Fievez, Veerle; Nguyen, Patrick; Hesta, Myriam

    2016-06-28

    Research in cats has shown that increased fermentation-derived propionic acid and its metabolites can be used as alternative substrates for gluconeogenesis, thus sparing amino acids for other purposes. This amino acid sparing effect could be of particular interest in patients with kidney or liver disease, where this could reduce the kidneys'/liver's burden of N-waste removal. Since dogs are known to have a different metabolism than the obligatory carnivorous cat, the main objective of this study was to assess the possibility of altering amino acid metabolism through intestinal fermentation in healthy dogs. This was studied by supplementing a low-protein diet with fermentable fibres, hereby providing an initial model for future studies in dogs suffering from renal/liver disease. Eight healthy dogs were randomly assigned to one of two treatment groups: sugar beet pulp and guar gum mix (SF: soluble fibre, estimated to mainly stimulate propionic acid production) or cellulose (IF: insoluble fibre). Treatments were incorporated into a low-protein (17 %) extruded dry diet in amounts to obtain similar total dietary fibre (TDF) contents for both diets (9.4 % and 8.2 % for the SF and IF diet, respectively) and were tested in a 4-week crossover feeding trial. Apparent faecal nitrogen digestibility and post-prandial fermentation metabolites in faeces and plasma were evaluated. Dogs fed the SF diet showed significantly higher faecal excretion of acetic and propionic acid, resulting in a higher total SCFA excretion compared to IF. SF affected the three to six-hour postprandial plasma acylcarnitine profile by significantly increasing AUC of acetyl-, propionyl-, butyryl- + isobutyryl-, 3-OH-butyryl-, 3-OH-isovaleryl- and malonyl-L-carnitine. Moreover, the amino acid plasma profile at that time was modified as leucine + isoleucine concentrations were significantly increased by SF, and a similar trend for phenylalanine and tyrosine's AUC was found. These results indicate

  7. Soluble adenylyl cyclase is an acid-base sensor in epithelial base-secreting cells.

    Science.gov (United States)

    Roa, Jinae N; Tresguerres, Martin

    2016-08-01

    Blood acid-base regulation by specialized epithelia, such as gills and kidney, requires the ability to sense blood acid-base status. Here, we developed primary cultures of ray (Urolophus halleri) gill cells to study mechanisms for acid-base sensing without the interference of whole animal hormonal regulation. Ray gills have abundant base-secreting cells, identified by their noticeable expression of vacuolar-type H(+)-ATPase (VHA), and also express the evolutionarily conserved acid-base sensor soluble adenylyl cyclase (sAC). Exposure of cultured cells to extracellular alkalosis (pH 8.0, 40 mM HCO3 (-)) triggered VHA translocation to the cell membrane, similar to previous reports in live animals experiencing blood alkalosis. VHA translocation was dependent on sAC, as it was blocked by the sAC-specific inhibitor KH7. Ray gill base-secreting cells also express transmembrane adenylyl cyclases (tmACs); however, tmAC inhibition by 2',5'-dideoxyadenosine did not prevent alkalosis-dependent VHA translocation, and tmAC activation by forskolin reduced the abundance of VHA at the cell membrane. This study demonstrates that sAC is a necessary and sufficient sensor of extracellular alkalosis in ray gill base-secreting cells. In addition, this study indicates that different sources of cAMP differentially modulate cell biology. Copyright © 2016 the American Physiological Society.

  8. Influence of biopolymers on the solubility of branched-chain amino acids and stability of their solutions.

    Science.gov (United States)

    Hong, Chi Rac; Lee, Gyu Whan; Paik, Hyun-Dong; Chang, Pahn-Shick; Choi, Seung Jun

    2018-01-15

    This study confirmed the possibility of biopolymer-type stabilizers to increase the saturation concentration of branched-chain amino acids by preventing their crystallization/precipitation. Although microfluidization increased the initial solubility, it failed to increase the saturation concentration of the branched-chain amino acids. The saturation concentration of the branched-chain amino acids increased from 3.81% to 4.42% and 4.85% after the incorporation of food hydrocolloids and proteins, respectively. However, the branched-chain amino acids:stabilizer ratio did not affect the solubility. In the case of food hydrocolloid-based solutions, crystal formation and growth of branched-chain amino acids occurred during storage, resulting in the precipitation of branched-chain amino acid crystals. However, food proteins effectively increased the stability of the solubilized branched-chain amino acids. The improved solubility and stability of the solubilized branched-chain amino acids could be attributed to interactions between the functional groups (carboxyl, amine, sulfate, aliphatic, aromatic, etc.) of the stabilizer and the branched-chain amino acid molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Phosphorus solubility in an acid forest soil as influenced by form of applied phosphorus and liming

    International Nuclear Information System (INIS)

    Fransson, Ann-Mari; Bergkvist, Bo; Tyler, Germund

    1999-01-01

    Sedimentary phosphorus, superphosphate, and wood-ash, as well as either sedimentary phosphorus. superphosphate or ash combined with lime, were distributed in selected plots in an 80-yr-old Norway spruce forest [Picea abies (L.) Karst]. After 2 yrs, the sedimentary phosphorus had increased the oxalate/oxalic acid-extractable P in the O-horizon, and the superphosphate had increased the oxalate/oxalic acid-extractable P in the E-horizon. At first, the percolation water from the superphosphate treatment showed high P concentrations. It soon returned to control levels, however. The percolation water from the sedimentary phosphorus treatment gradually showed increased phosphate concentrations. The wood-ash increased neither the amount of extractable P nor the P concentration in the percolation water. The oxalate/oxalic acid-extractable P from the sedimentary P treatment was reduced by liming. The P concentration in the percolation water also tended to be reduced. This was perhaps due to formation of Ca phosphates in the vicinity of the lime particles. In addition, if the solubility rate was similar to the uptake rate, it could account for the decreased P concentration

  10. Determination of solubility isotherms of barium and strontium nitrates in the system acetic acid-water at 250 C

    International Nuclear Information System (INIS)

    Hubicki, W.; Piskorek, M.

    1976-01-01

    Investigastions of the solubility of barium and strontium nitrates were carried out in the system: acetic acid - water at 25 0 C. When one compares the isotherms of solubility of barium and strontium nitrates, one can observe that it is possible to separate the admixtures of barium from strontium nitrates as a result of fractional crystallization of these nitrates from actic acid solution at the temperatures lower than 31.3 0 C, i.e. below the temperature of transformation: Sr(NO 3 ) 2 . 4H 2 O reversible to Sr(NO 3 ) 2 + 4H 2 O for aqueous solution. (author)

  11. Sialic Acid Binding Properties of Soluble Coronavirus Spike (S1 Proteins: Differences between Infectious Bronchitis Virus and Transmissible Gastroenteritis Virus

    Directory of Open Access Journals (Sweden)

    Christine Winter

    2013-07-01

    Full Text Available The spike proteins of a number of coronaviruses are able to bind to sialic acids present on the cell surface. The importance of this sialic acid binding ability during infection is, however, quite different. We compared the spike protein of transmissible gastroenteritis virus (TGEV and the spike protein of infectious bronchitis virus (IBV. Whereas sialic acid is the only receptor determinant known so far for IBV, TGEV requires interaction with its receptor aminopeptidase N to initiate infection of cells. Binding tests with soluble spike proteins carrying an IgG Fc-tag revealed pronounced differences between these two viral proteins. Binding of the IBV spike protein to host cells was in all experiments sialic acid dependent, whereas the soluble TGEV spike showed binding to APN but had no detectable sialic acid binding activity. Our results underline the different ways in which binding to sialoglycoconjugates is mediated by coronavirus spike proteins.

  12. Plasma concentrations of water-soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    2012-01-21

    Jan 21, 2012 ... histamine, hemoglobin, deoxyribonucleic acid (DNA), and ribonucleic .... workers who had more years of education and were better informed ..... Osuntokun BO, Aladetoyinbo A, Bademosi O. Vitamin B nutrition in the. Nigerian ...

  13. Authentication of dried distilled grain with solubles (DDGS) by fatty acid and volatile profiling.

    Science.gov (United States)

    Tres, Alba; Heenan, Samuel P; van Ruth, Saskia

    2014-11-01

    Demand for ethanol substituted fuels from the utilisation of cereal based biofuel has resulted in an over production of dried distillers grains with solubles (DDGS) that are now readily available on the animal feed market. With this rapid emerging availability comes potential variability in the nutritional value of DDGS and possible risks of feed contaminants. Subsequently, the authentication and traceability of alternative animal feed sources is of high priority. In this study and as part of the EU research project "Quality and Safety of Feeds and Food for Europe (QSAFFE FP7-KBBE-2010-4) an attempt was made to classify the geographical origin of cereal grains used in the production of DDGS material. DDGS material of wheat and corn origin were obtained from Europe, China, and the USA. Fatty acid profiles and volatile fingerprints were assessed by gas chromatography flame ionisation (GC-FID) and rapid proton transfer reaction mass spectrometry (PTR-MS) respectively. Chemometric analysis of fatty acid profiles and volatile fingerprints allowed for promising classifications of cereals used in DDGS material by geographical and botanical origin and enabled visual representation of the data. This objective analytical approach could be adapted for routine verification of cereal grains used in the production of DDGS material.

  14. Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Stanford, Lateefah A; Kim, Sunghwan; Klein, Geoffrey C; Smith, Donald F; Rodgers, Ryan P; Marshall, Alan G

    2007-04-15

    We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2.

  15. The participation of soluble factors in the omega-oxidation of fatty acids in the liver of the sheep

    International Nuclear Information System (INIS)

    Hare, W.R.; Wahle, K.W.

    1991-01-01

    The removal of soluble components from an ovine hepatic microsomal preparation decreased the omega-hydroxylation of dodecanoic and hexadecanoic acids. The results suggest that one or more soluble components play a role in the microsomal omega-hydroxylation of fatty acids. The possible roles in the reaction of catalase (known to stimulate the microsomal desaturations of fatty acids and alkylglycerols) and superoxide dismutase were investigated. The addition of these enzymes to the complete (but not the washed) microsomal preparation stimulated both the initial omega-hydroxylation reaction and the subsequent dehydrogenation reactions of the omega-oxidation pathway. The similarity of the effects of catalase and superoxide dismutase and stimulation of two different steps of the omega-oxidation pathway suggest that these agents are acting indirectly by removing active oxygen species rather than directly on the enzymes of microsomal fatty acid omega-hydroxylation

  16. Improving aqueous solubility and antitumor effects by nanosized gambogic acid-mPEG2000 micelles

    Directory of Open Access Journals (Sweden)

    Cai LL

    2013-12-01

    Full Text Available Lulu Cai,1,* Neng Qiu,2,* Mingli Xiang,3,* Rongsheng Tong,1 Junfeng Yan,1 Lin He,1 Jianyou Shi,1 Tao Chen,4 Jiaolin Wen,3 Wenwen Wang,3 Lijuan Chen31Department of Pharmacy, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, 2College of Materials and Chemistry and Chemical Engineering, Chengdu University of Technology, 3State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China; 4Faculty of Pharmacy, University of Montreal, Montreal, QC, Canada *These authors contributed equally to this paperAbstract: The clinical application of gambogic acid, a natural component with promising antitumor activity, is limited due to its extremely poor aqueous solubility, short half-life in blood, and severe systemic toxicity. To solve these problems, an amphiphilic polymer-drug conjugate was prepared by attachment of low molecular weight (ie, 2 kDa methoxy poly(ethylene glycol methyl ether (mPEG to gambogic acid (GA-mPEG2000 through an ester linkage and characterized by 1H nuclear magnetic resonance. The GA-mPEG2000 conjugates self-assembled to form nanosized micelles, with mean diameters of less than 50 nm, and a very narrow particle size distribution. The properties of the GA-mPEG2000 micelles, including morphology, stability, molecular modeling, and drug release profile, were evaluated. MTT (3-(4,5-dimethylthiazol-2-yl-2,5 diphenyl tetrazolium bromide tests demonstrated that the GA-mPEG2000 micelle formulation had obvious cytotoxicity to tumor cells and human umbilical vein endothelial cells. Further, GA-mPEG2000 micelles were effective in inhibiting tumor growth and prolonged survival in subcutaneous B16-F10 and C26 tumor models. Our findings suggest that GA-mPEG2000 micelles may have promising applications in tumor therapy.Keywords: gambogic acid, poly(ethylene glycol-drug conjugate, micelle, antitumor, toxicity

  17. The dynamics of acid-soluble phosphorus compounds in the course of winter and spring wheat germination under various thermic conditions. Part II. Labile phosphorus after hydrolysis of the acid-soluble fraction

    Directory of Open Access Journals (Sweden)

    A. Barbaro

    2015-06-01

    Full Text Available The changes in labile phosphorus compounds content during germination of wheat were investigated. These compounds were determined in acid-soluble germ extracts separated into fractions according to the solubility of their barium salts. Low germination temperature was found to raise the labile phosphorus content in the fraction of insoluble barium salts. If we assume that labile P of this fraction consisted mainly of adenosinedi- and triphosphates, it would seem that the rise, in the ATP and ADP level under the influence of low temperature may be essential for initiating flowering in winter varieties.

  18. RAGE receptor and its soluble isoforms in diabetes mellitus complications

    Directory of Open Access Journals (Sweden)

    Mauren Isfer Anghebem Oliveira

    2013-04-01

    Full Text Available Chronic hyperglycemia, which is present in all types of diabetes, increases the formation of advanced glycation end-products (AGEs. The interaction of AGEs with receptor of advanced glycation end-products (RAGE initiates a cascade of pro-inflammatory and pro-coagulant processes that result in oxidative stress, stimulating the formation and accumulation of more AGE molecules. This cyclic process, denominated metabolic memory, may explain the persistency of diabetic vascular complications in patients with satisfactory glycemic control. The RAGE found in several cell membranes is also present in soluble isoforms (esRAGE and cRAGE, which are generated by alternative deoxyribonucleic acid splicing or by proteolytic cleavage. This review focuses on new research into these mediators as potential biomarkers for vascular complications in diabetes.

  19. Quantifying solubility enhancement due to particle size reduction and crystal habit modification: case study of acetyl salicylic acid.

    Science.gov (United States)

    Hammond, Robert B; Pencheva, Klimentina; Roberts, Kevin J; Auffret, Tony

    2007-08-01

    The poor solubility of potential drug molecules is a significant problem in the design of pharmaceutical formulations. It is well known, however, that the solubility of crystalline materials is enhanced when the particle size is reduced to submicron levels and this factor can be expected to enhance drug product bioavailability. Direct estimation of solubility enhancement, as calculated via the Gibbs-Thompson relationship, demands reasonably accurate values for the particle/solution interfacial tension and, in particular, its anisotropy with respect to the crystal product's habit and morphology. In this article, an improved, more molecule-centered, approach is presented towards the calculation of solubility enhancement factors in which molecular modeling techniques are applied, and the effects associated with both crystal habit modification and solvent choice are examined. A case study for facetted, acetyl salicylic acid (aspirin) crystals in equilibrium with saturated aqueous ethanol solution reveals that their solubility will be enhanced in the range (7-58%) for a crystal size of 0.02 microm, with significantly higher enhancement for crystal morphologies in which the hydrophobic crystal faces are more predominant than the hydrophilic faces and for solvents in which the solubility is smaller. (c) 2007 Wiley-Liss, Inc. and the American Pharmacists Association.

  20. Solubility Limits of Dibutyl Phosphoric Acid in Uranium Solutions at SRS

    International Nuclear Information System (INIS)

    Thompson, M.C.; Pierce, R.A.; Ray, R.J.

    1998-06-01

    The Savannah River Site has enriched uranium (EU) solution which has been stored for almost 10 years since being purified in the second uranium cycle of the H area solvent extraction process. The concentrations in solution are 6 g/L U and about 0.1 M nitric acid. Residual tributylphosphate in the solutions has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 50 mg/L. Uranium is known to form compounds with DBP which have limited solubility. The potential to form uranium-DBP solids raises a nuclear criticality safety issue. SRTC tests have shown that U-DBP solids will precipitate at concentrations potentially attainable during storage of enriched uranium solutions. Evaporation of the existing EUS solution without additional acidification could result in the precipitation of U-DBP solids if DBP concentration in the resulting solution exceeds 110 ppm at ambient temperature. The same potential exists for evaporation of unwashed 1CU solutions. The most important variables of interest for present plant operations are HNO 3 and DBP concentrations. Temperature is also an important variable controlling precipitation. The data obtained in these tests can be used to set operating and safety limits for the plant. It is recommended that the data for 0 degrees C with 0.5 M HNO 3 be used for setting the limits. The limit would be 80 mg/L which is 3 standard deviations below the average of 86 observed in the tests. The data shows that super-saturation can occur when the DBP concentration is as much as 50 percent above the solubility limit. However, super-saturation cannot be relied on for maintaining nuclear criticality safety. The analytical method for determining DBP concentration in U solutions was improved so that analyses for a solution are accurate to within 10 percent. However, the overall uncertainty of results for periodic samples of the existing EUS solutions was only reduced slightly. Thus, sampling appears to be the largest portion

  1. Nucleic acid-binding glycoproteins which solubilize nucleic acids in dilute acid: re-examination of the Ustilago maydis glycoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Unrau, P.; Champ, D.R.; Young, J.L.; Grant, C.E.

    1980-01-01

    Holloman reported the isolation from Ustilago maydis of a glycoprotein which prevented the precipitation of nucleic acids in cold 5% trichloroacetic acid. Two glycoprotein fractions from U. maydis with this nucleic acid-solubilizing activity were isolated in our laboratory using improved purification procedures. The activity was not due to nuclease contamination. The glycoproteins are distinguished by: their ability to bind to concanavalin A-Sepharose; their differential binding to double- and single-stranded deoxyribonucleic acid, and to ribonucleic acid; their molecular weights (46,000 and 69,000); and the relative amounts present in growing versus nongrowing cells. Both fractions required sulfhydryl-reducing conditions for optimal yields, specific activity, and stability. Nucleic acid binding was cooperative, the minimum number of glycoproteins required to make a native T7 DNA molecule soluble in dilute acid being estimated at 2 and 15, respectively.

  2. Fermentation of calcium-fortified soymilk with Lactobacillus: effects on calcium solubility, isoflavone conversion, and production of organic acids.

    Science.gov (United States)

    Tang, A L; Shah, N P; Wilcox, G; Walker, K Z; Stojanovska, L

    2007-11-01

    The objective of this study was to enhance calcium solubility and bioavailability from calcium-fortified soymilk by fermentation with 7 strains of Lactobacillus, namely, L. acidophilus ATCC 4962, ATCC33200, ATCC 4356, ATCC 4461, L. casei ASCC 290, L. plantarum ASCC 276, and L. fermentum VRI-003. The parameters that were used are viability, pH, calcium solubility, organic acid, and biologically active isoflavone aglycone content. Calcium-fortified soymilk made from soy protein isolate was inoculated with these probiotic strains, incubated for 24 h at 37 degrees C, then stored for 14 d at 4 degrees C. Soluble calcium was measured using atomic absorption spectrophotometry (AA). Organic acids and bioactive isoflavone aglycones, including diadzein, genistein, and glycetein, were measured using HPLC. Viability of the strains in the fermented calcium-fortified soymilk was > 8.5 log(10) CFU/g after 24 h fermentation and this was maintained for 14-d storage at 4 degrees C. After 24 h, there was a significant increase (P casei ASCC 290 demonstrated the highest increase with 89.3% and 87.0% soluble calcium after 24 h, respectively. The increase in calcium solubility observed was related to lowered pH associated with production of lactic and acetic acids. Fermentation significantly increased (P < 0.05) the level of conversion of isoflavones into biologically active aglycones, including diadzein, genistein, and glycetein. Our results show that fermenting calcium-fortified soymilk with the selected probiotics can potentially enhance the calcium bioavailability of calcium-fortified soymilk due to increased calcium solubility and bioactive isoflavone aglycone enrichment.

  3. Forensic Discrimination of Concrete Pieces by Elemental Analysis of Acid-soluble Component with Inductively Coupled Plasma-Mass Spectrometry.

    Science.gov (United States)

    Kasamatsu, Masaaki; Igawa, Takao; Suzuki, Shinichi; Suzuki, Yasuhiro

    2018-01-01

    Since fragments of concrete can be evidence of crime, a determination of whether or not they come from the same origin is required. The authors focused on nitric acid-soluble components in the fragments of concrete. As a result of qualitative analysis with ICP-MS, it was confirmed that elements such as Cu, Zn, Rb, Sr, Zr, Ba, La, Ce, Nd, and Pb were contained in the fragments. After the nitric acid-soluble components in the fragments of concrete were separated by dissolving them in nitric acid, the concentrations of these elements in the dissolved solution were quantitatively determined by ICP-MS. The concentration ratios of nine elements compared to La were used as indicators. By comparing these indicators, it was possible to discriminate between the fragments of concrete.

  4. Magnetic hyperthermia studies on water-soluble polyacrylic acid-coated cobalt ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Krishna Surendra, M. [Indian Institute of Technology Madras, Department of Physics, Nano Functional Materials Technology Centre, Materials Research Centre (India); Annapoorani, S. [Anna University of Technology, Department of Nanotechnology (India); Ansar, Ereath Beeran; Harikrishna Varma, P. R. [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Bioceramics Laboratory (India); Ramachandra Rao, M. S., E-mail: msrrao@iitm.ac.in [Indian Institute of Technology Madras, Department of Physics, Nano Functional Materials Technology Centre, Materials Research Centre (India)

    2014-12-15

    We report on synthesis and hyperthermia studies in the water-soluble ferrofluid made of polyacrylic acid-coated cobalt ferrite (CoFe{sub 2}O{sub 4}) nanoparticles with different particle sizes. Magnetic nanoparticles were synthesized using co-precipitation method and particle size was varied as 6, 10, and 14 nm by varying the precursor to surfactant concentration. PAA surfactant bonding and surfactant thickness were studied by FTIR and thermogravimetric analysis. At room temperature, nanoparticles show superparamagnetism and saturation magnetization was found to vary from 33 to 44 emu/g with increase in the particle size from 6 to 14 nm, and this increase was attributed to the presence of a magnetic inert layer of 4 Å thick. Effect of particle size, concentration, and alternating magnetic field strength at 275 kHz on specific absorption rate were studied by preparing ferrofluids in deionized water at different concentrations. Ferrofluids at a concentration of 1.25 g/L, with 10 min of AMF exposure of strength ∼15.7 kA/m show stable temperatures ∼48, 58, and 68 °C with increase in the particle sizes 6, 10, and 14 nm. A maximum specific absorption rate of 251 W/g for ferrofluid with a particle size of 10 nm at 1.25 g/L, 15.7 kA/m, and 275 kHz was observed. Viability of L929 fibroblasts is measured by MTT assay cytotoxicity studies using the polyacrylic acid-coated CoFe{sub 2}O{sub 4} nanoparticles.

  5. Synthesis of water-soluble poly [acrylic acid-co-vinyl butyl ether] and its applications in cement admixtures

    International Nuclear Information System (INIS)

    Negim, S.M.; Mun, G.A.; Nurkeeva, Z.S.; Danveesh, H.H.M.

    2005-01-01

    Three composition ratios of poly[acrylic acid (AA)-co-vinyl butyl ether)] were prepared in alcoholic solution using azo-bis-isobutyro-nitrile as initiator (ABIN). The water-soluble copolymers were characterized through FT-IR, 1 H NMR, Mass spectra, ESEM as well as viscosity. The effect of water-soluble copolymers and their sodium salts on the physico-mechanical properties of Ordaniary Portland Cement (O.P.C) pastes was investigated. The results showed that the addition of aqueous solutions from the prepared copolymers and their sodium salts to the cement improve most of the specific characteristics of (O.P.C). As the concentration of the water-soluble copolymer increases, the setting time increases. The combined water content enhances the addition of copolymer to the mixing water. The compressive strength was she increased at all any hydration. The results of the solution of the prepared sodium salt copolymers are better than its copolymers. (author)

  6. Soluble epoxide hydrolase contamination of specific catalase preparations inhibits epoxyeicosatrienoic acid vasodilation of rat renal arterioles

    Science.gov (United States)

    Olson, Lauren; Harder, Adam; Isbell, Marilyn; Imig, John D.; Gutterman, David D.; Falck, J. R.; Campbell, William B.

    2011-01-01

    Cytochrome P-450 metabolites of arachidonic acid, the epoxyeicosatrienoic acids (EETs) and hydrogen peroxide (H2O2), are important signaling molecules in the kidney. In renal arteries, EETs cause vasodilation whereas H2O2 causes vasoconstriction. To determine the physiological contribution of H2O2, catalase is used to inactivate H2O2. However, the consequence of catalase action on EET vascular activity has not been determined. In rat renal afferent arterioles, 14,15-EET caused concentration-related dilations that were inhibited by Sigma bovine liver (SBL) catalase (1,000 U/ml) but not Calbiochem bovine liver (CBL) catalase (1,000 U/ml). SBL catalase inhibition was reversed by the soluble epoxide hydrolase (sEH) inhibitor tAUCB (1 μM). In 14,15-EET incubations, SBL catalase caused a concentration-related increase in a polar metabolite. Using mass spectrometry, the metabolite was identified as 14,15-dihydroxyeicosatrienoic acid (14,15-DHET), the inactive sEH metabolite. 14,15-EET hydrolysis was not altered by the catalase inhibitor 3-amino-1,2,4-triazole (3-ATZ; 10–50 mM), but was abolished by the sEH inhibitor BIRD-0826 (1–10 μM). SBL catalase EET hydrolysis showed a regioisomer preference with greatest hydrolysis of 14,15-EET followed by 11,12-, 8,9- and 5,6-EET (Vmax = 0.54 ± 0.07, 0.23 ± 0.06, 0.18 ± 0.01 and 0.08 ± 0.02 ng DHET·U catalase−1·min−1, respectively). Of five different catalase preparations assayed, EET hydrolysis was observed with two Sigma liver catalases. These preparations had low specific catalase activity and positive sEH expression. Mass spectrometric analysis of the SBL catalase identified peptide fragments matching bovine sEH. Collectively, these data indicate that catalase does not affect EET-mediated dilation of renal arterioles. However, some commercial catalase preparations are contaminated with sEH, and these contaminated preparations diminish the biological activity of H2O2 and EETs. PMID:21753077

  7. Carbon dioxide solubilities in decanoic acid-based hydrophobic deep eutectic solvents

    NARCIS (Netherlands)

    Zubeir, Lawien F.; Van Osch, Dannie J.G.P.; Rocha, Marisa A.A.; Banat, Fawzi; Kroon, Maaike C.

    2018-01-01

    The solubility of CO2 in hydrophobic deep eutectic solvents (DESs) has been measured for the first time. Six different hydrophobic DESs are studied in the temperature range from 298 to 323 K and at CO2 pressures up to 2 MPa. The results are evaluated by comparing the solubility data with existing

  8. Prevention of Acid Mine Drainage Through Complexation of Ferric Iron by Soluble Microbial Growth Products

    Science.gov (United States)

    Pandey, S.; Yacob, T. W.; Silverstein, J.; Rajaram, H.; Minchow, K.; Basta, J.

    2011-12-01

    Acid mine drainage (AMD) is a widespread environmental problem with deleterious impacts on water quality in streams and watersheds. AMD is generated largely by the oxidation of metal sulfides (i.e. pyrite) by ferric iron. This abiotic reaction is catalyzed by conversion of ferrous to ferric iron by iron and sulfur oxidizing microorganisms. Biostimulation is currently being investigated as an attempt to inhibit the oxidation of pyrite and growth of iron oxidizing bacteria through addition of organic carbon. This may stimulate growth of indigenous communities of acidophilic heterotrophic bacteria to compete for oxygen. The goal of this research is to investigate a secondary mechanism associated with carbon addition: complexation of free Fe(III) by soluble microbial growth products (SMPs) produced by microorganisms growing in waste rock. Exploratory research at the laboratory scale examined the effect of soluble microbial products (SMPs) on the kinetics of oxidation of pure pyrite during shaker flask experiments. The results confirmed a decrease in the rate of pyrite oxidation that was dependent upon the concentration of SMPs in solution. We are using these data to verify results from a pyrite oxidation model that accounts for SMPs. This reactor model involves differential-algebraic equations incorporating total component mass balances and mass action laws for equilibrium reactions. Species concentrations determined in each time step are applied to abiotic pyrite oxidation rate expressions from the literature to determine the evolution of total component concentrations. The model was embedded in a parameter estimation algorithm to determine the reactive surface area of pyrite in an abiotic control experiment, yielding an optimized value of 0.0037 m2. The optimized model exhibited similar behavior to the experiment for this case; the root mean squared of residuals for Fe(III) was calculated to be 7.58 x 10-4 M, which is several orders of magnitude less than the actual

  9. Acidity of cations and the solubility of oxides in the eutectic KCl-LiCl melt at 700 Deg C

    International Nuclear Information System (INIS)

    Cherginets, V.L.; Rebrova, T.P.

    1999-01-01

    Products of MgO, NiO and CoO solubility in KCl-LiCl melt at 700 Deg C were determined by the method of potentiometric titration using Pt(O 2 )IZrO 2 (Y 2 O 3 ) membrane oxygen electrode. It was ascertained that acid properties of Cd 2+ and Pb'2 + cations are levelled to Li + properties, a break in E-pO graduation dependence in KCl-LiCl melt was observed at pO ∼ 2. Increase in oxides solubility in the melt studied compared with KCl-NaCl and CsCl-KCl-NaCl melts stems from the presence of Li + cations in the melt studied, which possess stronger acid properties than those of Na + or K + [ru

  10. SOLUBILITIES AND PHYSICAL PROPERTIES OF SATURATED SOLUTIONS IN THE COPPER SULFATE + SULFURIC ACID + SEAWATER SYSTEM AT DIFFERENT TEMPERATURES

    Directory of Open Access Journals (Sweden)

    F. J. Justel

    2015-09-01

    Full Text Available AbstractIn Chile, the most important economic activity is mining, concentrated in the north of the country. This is a desert region with limited water resources; therefore, the mining sector requires research and identification of alternative sources of water. One alternative is seawater, which can be a substitute of the limited fresh water resources in the region. This work determines the influence of seawater on the solid-liquid equilibrium for acid solutions of copper sulfate at different temperatures (293.15 to 318.15 K, and its effect on physical properties (density, viscosity, and solubility. Knowledge of these properties and solubility data are useful in the leaching process and in the design of copper sulfate pentahydrate crystallization plants from the leaching process using seawater by means of the addition of sulfuric acid.

  11. Conformations and molecular interactions of poly-γ-glutamic acid as a soluble microbial product in aqueous solutions

    OpenAIRE

    Wang, Ling-Ling; Chen, Jian-Tao; Wang, Long-Fei; Wu, Sha; Zhang, Guang-zhao; Yu, Han-Qing; Ye, Xiao-dong; Shi, Qing-Shan

    2017-01-01

    Soluble microbial products (SMPs) are of significant concern in the natural environment and in engineered systems. In this work, poly-γ-glutamic acid (γ-PGA), which is predominantly produced by Bacillus sp., was investigated in terms of pH-induced conformational changes and molecular interactions in aqueous solutions; accordingly, its sedimentation coefficient distribution and viscosity were also elucidated. Experimental results indicate that pH has a significant impact on the structure and m...

  12. Effectiveness of anchovy substrate application on decreasing acid solubility of Sprague Dawley rats’ tooth enamel (in vivo)

    Science.gov (United States)

    Triputra, F.; Puspitawati, R.; Gunawan, H. A.

    2017-08-01

    Anchovies (Stolephorus insularis), a natural resource of Indonesia, contain fluoride in the form of CaF2 and can function as a fluoridation material to prevent dental caries. The aim of this study is to study the effectiveness of anchovy substrate, through food or topical application, in decreasing the acid solubility of tooth enamel. This research used 14 Sprague Dawley rats as subjects divided into the following 5 groups: baseline, experimental feeding, experimental smearing, and their negative controls. After 15 days of anchovy substrate application, lower incisors were extracted and the acid solubility of enamel was analyzed qualitatively and quantitatively using a stereo microscope and a Micro-Vickers Hardness Tester. Analysis of enamel surface destruction and enamel surface microscopic hardness shifting after a 60 sec application of H2PO4 (50% concentration) resulted in a decrease in acid solubility of enamel treated with anchovy substrate. This result can be seen with both the chewing and smearing method. S. insularis can be used as an alternative material for fluoridation.

  13. Thermodynamic properties of solubility of 2-methyl-5-arylfuran-3-carboxylic acids in organic solvents

    Czech Academy of Sciences Publication Activity Database

    Sobechko, I.; Dibrivnyi, V.; Horak, Y.; Velychkivska, Nadiia; Kochubei, V.; Obushak, M.

    2017-01-01

    Roč. 11, č. 4 (2017), s. 397-404 ISSN 1996-4196 Institutional support: RVO:61389013 Keywords : enthalpy * entropy * Gibbs energy of solubility Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science

  14. In vitro solubility of calcium, iron and zinc in relation to phytic acid levels in rice-based consumer products in China

    NARCIS (Netherlands)

    Liang, J.; Han, B.Z.; Nout, M.J.R.; Hamer, R.J.

    2010-01-01

    In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and

  15. Profiling of the Contents of Amino Acids, Water-Soluble Vitamins, Minerals, Sugars and Organic Acids in Turkish Hazelnut Varieties

    Directory of Open Access Journals (Sweden)

    Taş Neslihan Göncüoğlu

    2018-09-01

    Full Text Available Proximate composition, profiles of amino acids, sugars, organic acids, vitamins and minerals of fourteen Turkish hazelnut varieties harvested in 2013 and 2014 were investigated. Glutamic acid, arginine and aspartic acid were the most predominant amino acids, representing of about 50% of hazelnut protein. Individual amino acid profiles showed significant differences depending upon the harvest year (p<0.05. Concentration of sucrose was the highest followed by fructose, glucose, stachyose, raffinose and myo-inositol, respectively. Phytic acid was predominant organic acid in all varieties, followed by malic acid. Independent of the variety, hazelnuts were rich in pantothenic acid, nicotinic acid, pyridoxal, biotin, thiamine, nicotinamide. Pantothenic and nicotinic acid were significantly higher in most of the varieties in harvest year 2014. Potassium was the most predominant mineral, followed by magnesium, calcium, sodium, manganese, zinc, iron and copper, respectively.

  16. Amplification of deoxyribonucleic acid (DNA) fragment using two ...

    African Journals Online (AJOL)

    user

    2011-04-11

    Apr 11, 2011 ... polymerases on this method, whether different lengths of. DNA fragments could be amplified by two-step PCR and the difference of DNA product quality produced by the two methods. MATERIALS AND METHODS. PCR template and reagents. Enterobacteria phage lambda DNA (GenBank no: V00636) ...

  17. Reversible entrapment of plasmid deoxyribonucleic acid on different chromatographic supports.

    Science.gov (United States)

    Gabor, Boštjan; Černigoj, Urh; Barut, Miloš; Štrancar, Aleš

    2013-10-11

    HPLC based analytical assay is a powerful technique that can be used to efficiently monitor plasmid DNA (pDNA) purity and quantity throughout the entire purification process. Anion exchange monolithic and non-porous particle based stationary phases were used to study the recovery of the different pDNA isoforms from the analytical column. Three differently sized pDNA molecules of 3.0kbp, 5.2kbp and 14.0kbp were used. Plasmid DNA was injected onto columns under the binding conditions and the separation of the isoforms took place by increasing the ionic strength of the elution buffer. While there was no substantial decrease of the recovered supercoiled and linear isoforms of the pDNA with the increase of the plasmid size and with the increase of the flow rate (recoveries in all cases larger than 75%), a pronounced decrease of the oc isoform recovery was observed. The entrapment of the oc pDNA isoform occurred under non-binding conditions as well. The partial oc isoform elution from the column could be achieved by decreasing the flow rate of the elution mobile phase. The results suggested a reversible entrapment of the oc isoform in the restrictions within the pores of the monolithic material as well as within the intra-particle space of the non-porous particles. This phenomenon was observed on both types of the stationary phase morphologies and could only be connected to the size of a void space through which the pDNA needs to migrate. A prediction of reversible pDNA entrapment was successfully estimated with the calculation of Peclet numbers, Pe, which defines the ratio between a convective and diffusive mass transport. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Host Specificity of Salmonella typhimurium Deoxyribonucleic Acid Restriction and Modification

    Science.gov (United States)

    Slocum, Harvey; Boyer, Herbert W.

    1973-01-01

    The restriction and modification genes of Salmonella typhimurium which lie near the thr locus were transferred to a restrictionless mutant of Escherichia coli. These genes were found to be allelic to the E. coli K, B, and A restriction and modification genes. E. coli recombinants with the restriction and modification host specificity of S. typhimurium restricted phage λ that had been modified by each of the seven known host specificities of E. coli at efficiency of plating levels of about 10−2. Phage λ modified with the S. typhimurium host specificity was restricted by six of the seven E. coli host specificities but not by the RII (fi− R-factor controlled) host specificity. It is proposed that the restriction and modification enzymes of this S. typhimurium host specificity have two substrates, one of which is a substrate for the RII host specificity enzymes. PMID:4570605

  19. The nature of radiolesions in deoxyribonucleic acid and their repair

    International Nuclear Information System (INIS)

    Moustacchi, E.

    1976-01-01

    The nature of different damages induced by ionizing radiations in DNA is described. The main lesions are single strand breaks, double strands breaks and base modifications. The principal enzymatic repair systems are recalled [fr

  20. Soluble and cell wall-bound phenolic acids and ferulic acid dehydrodimers in rye flour and five bread model systems: insight into mechanisms of improved availability.

    Science.gov (United States)

    Dynkowska, Wioletta M; Cyran, Malgorzata R; Ceglińska, Alicja

    2015-03-30

    The bread-making process influences bread components, including phenolics that significantly contribute to its antioxidant properties. Five bread model systems made from different rye cultivars were investigated to compare their impact on concentration of ethanol-soluble (free and ester-bound) and insoluble phenolics. Breads produced by a straight dough method without acid addition (A) and three-stage sourdough method with 12 h native starter preparation (C) exhibited the highest, genotype-dependent concentrations of free phenolic acids. Dough acidification by direct acid addition (method B) or by gradual production during prolonged starter fermentation (24 and 48 h, for methods D and E) considerably decreased their level. However, breads B were enriched in soluble ester-bound fraction. Both direct methods, despite substantial differences in dough pH, caused a similar increase in the amount of insoluble ester-bound fraction. The contents of phenolic fractions in rye bread were positively related to activity level of feruloyl esterase and negatively to those of arabinoxylan-hydrolysing enzymes in wholemeal flour. The solubility of rye bread phenolics may be enhanced by application of a suitable bread-making procedure with respect to rye cultivar, as the mechanisms of this process are also governed by a response of an individual genotype with specific biochemical profile. © 2014 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  1. Measurement and prediction of the solubility of acid gases in monoethanolamine solutions at low partial pressures

    Energy Technology Data Exchange (ETDEWEB)

    Nasir, P; Mather, A E

    1977-12-01

    An apparatus for the determination of the solubility of hydrogen sulfide, carbon dioxide, and their mixtures in ethanolamine solutions at low pressures is described. With this apparatus, the solubility of H/sub 2/S, CO/sub 2/ and their mixtures in aqueous solutions of monoethanolamine was measured at partial pressures between 0.001 kPa and 9 kPa at temperatures of 80 and 100/sup 0/C. The results for the mixture were compared with two methods of prediction based on a thermodynamic model. 6 figures, 4 tables.

  2. Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

    OpenAIRE

    Maree, M. David; Neuse, Eberhard W.; Erasmus, Elizabeth; Swarts, Jannie C.

    2007-01-01

    The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymer...

  3. Isolation and characterization of acid-soluble collagen from the scales of marine fishes from Japan and Vietnam.

    Science.gov (United States)

    Minh Thuy, Le Thi; Okazaki, Emiko; Osako, Kazufumi

    2014-04-15

    Acid-soluble collagen (ASC) was successfully extracted from the scales of lizard fish (Saurida spp.) and horse mackerel (Trachurus japonicus) from Japan and Vietnam and grey mullet (Mugil cephalis), flying fish (Cypselurus melanurus) and yellowback seabream (Dentex tumifrons) from Japan. ASC yields were about 0.43-1.5% (on a dry weight basis), depending on the species. The SDS-PAGE profile showed that the ASCs were type I collagens, and consisted of two different α chains, α1 and α2, as well as a β component. ASC of horse mackerel from Vietnam contained a higher imino acid level than that from Japan. ASC denaturation temperature (Td) ranged from 26 to 29 °C, depending on fish species and imino acid content (p0.4M, regardless of fish type. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Kinetics of Acid Hydrolysis of Water-Soluble Spruce O-Acetyl Galactoglucomannans

    NARCIS (Netherlands)

    Xu, C.; Pranovich, A.; Vahasalo, L.; Hemming, J.; Holmbom, B.; Schols, H.A.; Willfor, S.

    2008-01-01

    Water-soluble O-acetyl galactoglucomannan (GGM) is a softwood-derived polysaccharide, which can be extracted on an industrial scale from wood or mechanical pulping waters and now is available in kilogram scale for research and development of value-added products. To develop applications of GGM,

  5. Solubility of Ferulic Acid in Supercritical Carbon Dioxide with Ethanol as Cosolvent

    Czech Academy of Sciences Publication Activity Database

    Sovová, Helena

    2001-01-01

    Roč. 46, č. 5 (2001), s. 1255-1257 ISSN 0021-9568 R&D Projects: GA ČR GA203/98/1445 Institutional research plan: CEZ:AV0Z4072921 Keywords : solubility * supercritical carbon * ethanol Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.960, year: 2001

  6. Neptunium (IV) oxalate solubility

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1983-07-01

    The equilibrium solubility of neptunium (IV) oxalate in nitric/oxalic acid solutions was determined at 22 0 C, 45 0 C, and 60 0 C. The concentrations of nitric/oxalic acid solutions represented a wide range of free oxalate ion concentration. A mathematical solubility model was developed which is based on the formation of the known complexes of neptunium (IV) oxalate. the solubility model uses a simplified concentration parameter which is proportional to the free oxalate ion concentration. The solubility model can be used to estimate the equilibrium solubility of neptunium (IV) oxalate over a wide range of oxalic and nitric acid concentrations at each temperature

  7. Effect of Different Inclusion Level of Condensed Distillers Solubles Ratios and Oil Content on Amino Acid Digestibility of Corn Distillers Dried Grains with Solubles in Growing Pigs

    Directory of Open Access Journals (Sweden)

    P. Li

    2015-01-01

    Full Text Available The purpose of this experiment was to determine and compare the digestibility of crude protein (CP and amino acids (AA in full-oil (no oil extracted and de-oiled (oil extracted corn distillers dried grains with solubles (DDGS with different condensed distillers solubles (CDS ratios. Six barrows (29.6±2.3 kg fitted with ileal T-cannula were allotted into a 6×6 Latin square design. Each period was comprised of a 5-d adaption period followed by a 2-d collection of ileal digesta. The five test diets contained 62% DDGS as the sole source of AA. A nitrogen-free diet was used to measure the basal endogenous losses of CP and AA. Chromic oxide (0.3% was used as an index in each diet. The results showed that CP and AA were very similar in 5 DDGS, but the standardized ileal digestibility (SID of lysine (from 56.16% to 71.15% and tryptophan (from 54.90% to 68.38% had the lowest values and largest variation within the essential AA, which suggests reduced availability of AA and different levels of Maillard reactions in the five DDGS. The apparent ileal digestibility and SID of CP and most of AA in full-oil DDGS (sources 1 and 2 were greater (p0.05 than full-oil with high CDS ratio DDGS (source 2; however, the SID of most AA of de-oiled with low CDS ratios DDGS (source 3 were non-significantly lower (p>0.05 than de-oiled with high CDS ratio DDGS (source 4; and the de-oiled DDGS with middle CDS ratio (source 5 but with different drying processing had the lowest SID AA values. In conclusion, de-oiled DDGS had lower SID of CP and AA than full-oil DDGS; a higher CDS ratio tended to decrease the SID of AA in full-oil DDGS but not in de-oiled DDGS; and compared with CDS ratio, processing, especially drying, may have more of an effect on AA digestibility of DDGS.

  8. The use of water-soluble hydrazones as inhibitors for the corrosion of C-steel in acidic medium

    International Nuclear Information System (INIS)

    Moussa, M.N.H.; El-Far, A.A.; El-Shafei, A.A.

    2007-01-01

    Inhibition efficiency of some water-soluble hydrazones for C-steel corrosion in hydrochloric acid has been tested by weight loss, polarisation measurements and open circuit technique. The inhibition effect was attributed to the adsorption of the additives on the C-steel surface as supported by adsorption measurements at Pt electrode using cyclic voltammetry. Electrochemical measurements indicated that all the additives behave as cathodic-type inhibitors. The data obtained fit well to both the Temkin adsorption isotherm and the kinetic-thermodynamic model. The inhibition behaviour and its order were explained with the help of the proposed skeletal representation

  9. The use of water-soluble hydrazones as inhibitors for the corrosion of C-steel in acidic medium

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, M.N.H.; El-Far, A.A. [Department of Chemistry, Faculty of Science, Mansoura University, ET-35516 Mansoura (Egypt); El-Shafei, A.A. [Department of Chemistry, Faculty of Science, Mansoura University, ET-35516 Mansoura (Egypt)], E-mail: ashafei@mans.edu.eg

    2007-09-15

    Inhibition efficiency of some water-soluble hydrazones for C-steel corrosion in hydrochloric acid has been tested by weight loss, polarisation measurements and open circuit technique. The inhibition effect was attributed to the adsorption of the additives on the C-steel surface as supported by adsorption measurements at Pt electrode using cyclic voltammetry. Electrochemical measurements indicated that all the additives behave as cathodic-type inhibitors. The data obtained fit well to both the Temkin adsorption isotherm and the kinetic-thermodynamic model. The inhibition behaviour and its order were explained with the help of the proposed skeletal representation.

  10. Gallic acid/hydroxypropyl-β-cyclodextrin complex: Improving solubility for application on in vitro/ in vivo Candida albicans biofilms.

    Directory of Open Access Journals (Sweden)

    Guilherme Rodrigues Teodoro

    Full Text Available The aim of this study was to increase the solubility of gallic acid (GA for the treatment of Candida albicans biofilm, which is very difficult to treat and requires high drug concentrations. Cyclodextrins (CDs were used for this purpose. Complexes were evaluated by phase-solubility studies, prepared by spray drying and characterized by drug loading, scanning electron microscopy (SEM and differential scanning calorimetry (DSC. The complexes were tested on C. albicans biofilm using in vitro and in vivo models. HPβCD formed soluble inclusion complexes with GA. The percentage of GA in GA/HPβCD was 10.8 ± 0.01%. The SEM and DSC analyses confirmed the formation of inclusion complexes. GA/HPβCD maintained the antimicrobial activity of the pure GA. GA/HPβCD was effective on C. albicans biofilms of 24 and 48h. The in vivo results showed an anti-inflammatory activity of GA/HPβCD with no difference in invading hypha counting among the groups. This study encourages the development of new antifungal agents.

  11. Measurement and modelling of urea solubility in aqueous propane-1,2,3-triol and prop-2-enoic acid solutions

    International Nuclear Information System (INIS)

    Santos, Jéssica dos J; Rocha, João A.A.B.; Costa, Glória M.N.; Cabral-Albuquerque, Elaine C.M.; Alves, Tito L.M.; Pinto, José C.; Fialho, Rosana L.

    2016-01-01

    Highlights: • Solubilities were shown to increase with temperature and to decrease with the increasing organic solvent content. • The UNIFAC method provided good fitting of the available data, after the estimation of a single model parameter. • The empirical method showed to be more efficient to describe several solution concentrations however, it is not predictive. - Abstract: The aim of the present study is to measure the solubility of urea in aqueous solutions of prop-2-enoic acid and propane-1,2,3-triol, as these compounds are used as co-monomers to produce urea base co-polymers. Experimental values have been obtained at several concentrations and temperatures. Solubility results were modelled with the help of an exponential empirical correlation, ideal solid-liquid equilibrium correlation and the Universal Functional Activity Coefficient (UNIFAC) method, used to describe the activity coefficient in the liquid phase. The empirical correlation requires two empirical parameters for each solvent and leads to the best fit for the available data. The UNIFAC method correlation also has a good numerical performance and is completely predictive, and it does not require the estimation of additional parameters.

  12. Effect of Acid Hydrolysis and Thermal Hydrolysis on Solubility and Properties of Oil Palm Empty Fruit Bunch Fiber Cellulose Hydrogel

    Directory of Open Access Journals (Sweden)

    Sinyee Gan

    2015-11-01

    Full Text Available Cellulose hydrogel was produced from pretreated oil palm empty fruit bunch fiber (EFB that went through acid hydrolysis and thermal hydrolysis. The pretreated EFB was dissolved in LiOH/urea aqueous solution using the rapid dissolution method and was subjected to a crosslinking process with the aid of epichlorohydrin to form hydrogel. The effects of both hydrolyses’ time on average molecular weight (Mŋ, solubility, and properties of EFB hydrogels were evaluated. Both hydrolyses led to lower Mŋ, lower crystallinity index (CrI and hence, resulted in higher cellulose solubility. X-ray diffraction (XRD characterization revealed the CrI and transition of crystalline structure of EFB from cellulose I to II. The effects of hydrolysis time on the transparency, degree of swelling (DS, and morphology of the regenerated cellulose hydrogel were also investigated using an ultraviolet-visible (UV-Vis spectrophotometer and a Field emission scanning electron microscope (FESEM, respectively. These findings provide an efficient method to improve the solubility and properties of regenerated cellulose products.

  13. The Solubility of metal oxides in molten carbonates - why the acid-basic chemistry fails?

    DEFF Research Database (Denmark)

    Bjerrum, Niels; Qingfeng, Li; Borup, Flemming

    1999-01-01

    Solubilities of various metal oxides in molten Li/K carbonates have been measured at 650°C under carbon dioxide atmosphere. It is found that the solubility of NiO and PbO decreases with increasing lithium mole fraction and decreasing CO2 partial pressure. On the other hand, the emf measurement...... shows opposite effects, i.e., decreasing CO2 pressure leads to more negative emf values but increasing lithium content gives more positive emf values. This contradiction is explained by means of a complex formation model. The possible species for lead are proposed to be [Pb(CO3)2]-2 and/or [Pb(CO3) 3...

  14. Solubility of DCH18C6 and n-octanol in nitric acid system

    International Nuclear Information System (INIS)

    He Qiange; Wang Jianchen; Chen Jing

    2011-01-01

    Equilibrium solubility of DCH18C6 and n-octanol in aqueous solution were determined by GC. And effects of temperature, concentration of Sr 2+ or HNO 3 were studied. The results indicate that solubility of DCH18C6 is substantial and make the crown ether continually drain from organic phase which could be 3% at most. As diluent, n-octanol could dissolve in water with certain quantity. So n-octanol, and then kerosene should be used to extract DCH18C6 and n-octanol from aqueous phase. Or toluene is taken to recover DCH18C6 and n-octanol at the same time. Above extractants could recover more than 99% of solute from aqueous solution in the volume ratio 1:1. (author)

  15. Ferulic Acid Dehydrodimer and –Dehydrotrimer Profiles of Distillers Dried Grains with Solubles from Different Cereal Species

    DEFF Research Database (Denmark)

    Pedersen, Mads Brøgger; Bunzel, Mirko; Schäfer, Judith

    2015-01-01

    Ferulic acid dehydrodimers- (DFA) and trimers (TriFA) ester-linked to plant cell wall polymers may not only cross-link cell wall polysaccharides, but also other cell wall components including proteins and lignin, thus, enhancing the rigidity and potentially affect the enzymatic degradation...... of the plant cell wall. Corn-, wheat-, and mixed cereal distillers dried grains with solubles (DDGS) were investigated for composition of DFAs and TriFAs by reversed phase high performance liquid chromatography with ultra violet detection. Corn DDGS contained 5.3 and 5.9 times higher contents of total DFAs...... acid cross-links in the corn cell wall are presumably not modified during fermentation and DDGS processing....

  16. Increase on the initial soluble heme levels in acidic conditions is an important mechanism for spontaneous heme crystallization in vitro.

    Directory of Open Access Journals (Sweden)

    Renata Stiebler

    Full Text Available BACKGROUND: Hemozoin (Hz is a heme crystal that represents a vital pathway for heme disposal in several blood-feeding organisms. Recent evidence demonstrated that β-hematin (βH (the synthetic counterpart of Hz formation occurs under physiological conditions near synthetic or biological hydrophilic-hydrophobic interfaces. This seems to require a heme dimer acting as a precursor of Hz crystals that would be formed spontaneously in the absence of the competing water molecules bound to the heme iron. Here, we aimed to investigate the role of medium polarity on spontaneous βH formation in vitro. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the effect of water content on spontaneous βH formation by using the aprotic solvent dimethylsulfoxide (DMSO and a series of polyethyleneglycols (PEGs. We observed that both DMSO and PEGs (3.350, 6.000, 8.000, and 22.000 increased the levels of soluble heme under acidic conditions. These compounds were able to stimulate the production of βH crystals in the absence of any biological sample. Interestingly, the effects of DMSO and PEGs on βH formation were positively correlated with their capacity to promote previous heme solubilization in acidic conditions. Curiously, a short chain polyethyleneglycol (PEG 300 caused a significant reduction in both soluble heme levels and βH formation. Finally, both heme solubilization and βH formation strongly correlated with reduced medium water activity provided by increased DMSO concentrations. CONCLUSIONS: The data presented here support the notion that reduction of the water activity is an important mechanism to support spontaneous heme crystallization, which depends on the previous increase of soluble heme levels.

  17. Utilization of Condensed Distillers Solubles as Nutrient Supplement for Production of Nisin and Lactic Acid from Whey

    Science.gov (United States)

    Liu, Chuanbin; Hu, Bo; Chen, Shulin; Glass, Richard W.

    The major challenge associated with the rapid growth of the ethanol industry is the usage of the coproducts, i.e., condensed distillers solubles (CDS) and distillers dried grains, which are currently sold as animal feed supplements. As the growth of the livestock industries remains flat, alternative usage of these coproducts is urgently needed. CDS is obtained after the removal of ethanol by distillation from the yeast fermentation of a grain or a grain mixture by condensing the thin stillage fraction to semisolid. In this work, CDS was first characterized and yeast biomass was proven to be the major component of CDS. CDS contained 7.50% crude protein but with only 42% of that protein being water soluble. Then, CDS was applied as a nutrient supplement for simultaneous production of nisin and lactic acid by Lactococcus lactis subsp. lactis (ATCC 11454). Although CDS was able to support bacteria growth and nisin production, a strong inhibition was observed when CDS was overdosed. This may be caused by the existence of the major ethanol fermentation byproducts, especially lactate and acetate, in CDS. In the final step, the CDS based medium composition for nisin and lactic acid production was optimized using response surface methodology.

  18. Solvent-Free Polymerization of L-Aspartic Acid in the Presence of D-Sorbitol to Obtain Water Soluble or Network Copolymers

    Science.gov (United States)

    L-aspartic acid was thermally polymerized in the presence of D-sorbitol with the goal of synthesizing new, higher molecular weight water soluble and absorbent copolymers. No reaction occurred when aspartic acid alone was heated at 170 or 200 degrees C. In contrast, heating sorbitol and aspartic ac...

  19. Influence of cold stress on contents of soluble sugars, vitamin C and free amino acids including gamma-aminobutyric acid (GABA) in spinach (Spinacia oleracea).

    Science.gov (United States)

    Yoon, Young-Eun; Kuppusamy, Saranya; Cho, Kye Man; Kim, Pil Joo; Kwack, Yong-Bum; Lee, Yong Bok

    2017-01-15

    The contents of soluble sugars (sucrose, fructose, glucose, maltose and raffinose), vitamin C and free amino acids (34 compounds, essential and non-essential) were quantified in open-field and greenhouse-grown spinaches in response to cold stress using liquid chromatography. In general, greenhouse cultivation produced nutritionally high value spinach in a shorter growing period, where the soluble sugars, vitamin C and total amino acids concentrations, including essential were in larger amounts compared to those grown in open-field scenarios. Further, low temperature exposure of spinach during a shorter growth period resulted in the production of spinach with high sucrose, ascorbate, proline, gamma-aminobutyric acid, valine and leucine content, and these constitute the most important energy/nutrient sources. In conclusion, cultivation of spinach in greenhouse at a low temperature (4-7°C) and exposure for a shorter period (7-21days) before harvest is recommended. This strategy will produce a high quality product that people can eat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Amino acids as co-amorphous stabilizers for poorly water-soluble drugs - Part 2

    DEFF Research Database (Denmark)

    Löbmann, K.; Laitinen, R.; Strachan, C.

    2013-01-01

    spectroscopy. Molecular interactions of the drugs carbamazepine and indomethacin with the amino acids arginine, phenylalanine, and tryptophan were investigated. The amino acids were chosen from the biological target site of both drugs and prepared as co-amorphous formulations together with the drugs...

  1. Solubility of jarosite solid solutions precipitated from acid mine waters, Iron Mountain, California

    Science.gov (United States)

    Alpers, Charles N.; Nordstrom, D. Kirk; Ball, J.W.

    1989-01-01

    Because of the common occurrence of 15 to 25 mole percent hydronium substitution on the alkali site in jarosites, it is necessary to consider the hydronium content of jarosites in any attempt at rigorous evaluation of jarosite solubility or of the saturation state of natural waters with respect to jarosite. A Gibbs free energy of 3293.5±2.1 kJ mol-1 is recommended for a jarosite solid solution of composition K.77Na.03(H3O).20Fe3(SO4)2(OH)6. Solubility determinations for a wider range of natural and synthetic jarosite solid solutions will be necessary to quantify the binary and ternary mixing parameters in the (K-Na-H3O) system. In the absence of such studies, molar volume data for endmember minerals indicate that the K-H3O substitution in jarosite is probably closer to ideal mixing than either the Na-K or Na-H3O substitution.

  2. Hygroscopic properties of internally mixed particles composed of NaCl and water-soluble organic acids.

    Science.gov (United States)

    Ghorai, Suman; Wang, Bingbing; Tivanski, Alexei; Laskin, Alexander

    2014-02-18

    Atmospheric aging of naturally emitted marine aerosol often leads to formation of internally mixed particles composed of sea salts and water-soluble organic compounds of anthropogenic origin. Mixing of sea salt and organic components has profound effects on the evolving chemical composition and hygroscopic properties of the resulted particles, which are poorly understood. Here, we have studied chemical composition and hygroscopic properties of laboratory generated NaCl particles mixed with malonic acid (MA) and glutaric acid (GA) at different molar ratios using micro-FTIR spectroscopy, atomic force microscopy, and X-ray elemental microanalysis. Hygroscopic properties of internally mixed NaCl and organic acid particles were distinctly different from pure components and varied significantly with the type and amount of organic compound present. Experimental results were in a good agreement with the AIM modeling calculations of gas/liquid/solid partitioning in studied systems. X-ray elemental microanalysis of particles showed that Cl/Na ratio decreased with increasing organic acid component in the particles with MA yielding lower ratios relative to GA. We attribute the depletion of chloride to the formation of sodium malonate and sodium glutarate salts resulted by HCl evaporation from dehydrating particles.

  3. Hygroscopic properties of ultrafine aerosol particles in the boreal forest: diurnal variation, solubility and the influence of sulfuric acid

    Directory of Open Access Journals (Sweden)

    M. Ehn

    2007-01-01

    Full Text Available The hygroscopic growth of aerosol particles present in a boreal forest was measured at a relative humidity of 88%. Simultaneously the gas phase concentration of sulfuric acid, a very hygroscopic compound, was monitored. The focus was mainly on days with new particle formation by nucleation. The measured hygroscopic growth factors (GF correlated positively with the gaseous phase sulfuric acid concentrations. The smaller the particles, the stronger the correlation, with r=0.20 for 50 nm and r=0.50 for 10 nm particles. The increase in GF due to condensing sulfuric acid is expected to be larger for particles with initially smaller masses. During new particle formation, the changes in solubility of the new particles were calculated during their growth to Aitken mode sizes. As the modal diameter increased, the solubility of the particles decreased. This indicated that the initial particle growth was due to more hygroscopic compounds, whereas the later growth during the evening and night was mainly caused by less hygroscopic or even hydrophobic compounds. For all the measured sizes, a diurnal variation in GF was observed both during days with and without particle formation. The GF was lowest at around midnight, with a mean value of 1.12–1.24 depending on particle size and if new particle formation occurred during the day, and increased to 1.25–1.34 around noon. This can be tentatively explained by day- and nighttime gas-phase chemistry; different vapors will be present depending on the time of day, and through condensation these compounds will alter the hygroscopic properties of the particles in different ways.

  4. Defensive strategies in Geranium sylvaticum, Part 2: Roles of water-soluble tannins, flavonoids and phenolic acids against natural enemies.

    Science.gov (United States)

    Tuominen, Anu

    2013-11-01

    Geranium sylvaticum is a common herbaceous plant in Fennoscandia, which has a unique phenolic composition. Ellagitannins, proanthocyanidins, galloylglucoses, gallotannins, galloyl quinic acids and flavonoids possess variable distribution in its different organs. These phenolic compounds are thought to have an important role in plant-herbivore interactions. The aim of this study was to quantify these different water-soluble phenolic compounds and measure the biological activity of the eight organs of G. sylvaticum. Compounds were characterized and quantified using HPLC-DAD/MS, in addition, total proanthocyanidins were determined by BuOH-HCl assay and total phenolics by the Folin-Ciocalteau method. Two in vitro biological activity measurements were used: the prooxidant activity was measured by the browning assay and antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Organ extracts were fractionated using column chromatography on Sephadex LH-20 and the activities of fractions was similarly measured to evaluate which polyphenol groups contributed the most to the biological activity of each organ. The data on the activity of fractions were examined by multivariate data analysis. The water-soluble extracts of leaves and pistils, which contained over 30% of the dry weight as ellagitannins, showed the highest pro-oxidant activity among the organ extracts. Fraction analysis revealed that flavonoids and galloyl quinic acids also exhibited high pro-oxidant activity. In contrast, the most antioxidant active organ extracts were those of the main roots and hairy roots that contained high amounts of proanthocyanidins in addition to ellagitannins. Analysis of the fractions showed that especially ellagitannins and galloyl quinic acids have high antioxidant activity. We conclude that G. sylvaticum allocates a significant amount of tannins in those plant parts that are important to the fitness of the plant and susceptible to natural enemies, i

  5. Solubilities of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid in water

    Energy Technology Data Exchange (ETDEWEB)

    Mishelevich, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel); Apelblat, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel)], E-mail: apelblat@bgu.ac.il

    2008-05-15

    The solubility in water of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid was determined in the 278.15 K to 343.15 K temperature range. The solubility of these compounds served to permit the evaluation of the apparent molar enthalpies of solution.

  6. Solubilities of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid in water

    International Nuclear Information System (INIS)

    Mishelevich, Alexander; Apelblat, Alexander

    2008-01-01

    The solubility in water of magnesium-L-ascorbate, calcium-L-ascorbate, magnesium-L-glutamate, magnesium-D-gluconate, calcium-D-gluconate, calcium-D-heptagluconate, L-aspartic acid, and 3-nitrobenzoic acid was determined in the 278.15 K to 343.15 K temperature range. The solubility of these compounds served to permit the evaluation of the apparent molar enthalpies of solution

  7. Effect of Difference in Fatty Acid Chain Lengths of Medium- Chain Lipids on Lipid/Surfactant/Water Phase Diagrams and Drug Solubility

    Directory of Open Access Journals (Sweden)

    Hetal N. Prajapati

    2011-09-01

    Full Text Available Lipids consisting of medium chain fatty acids are commonly used in the development of lipid-based selfemulsifying and self-microemulsifying drug delivery systems. However, no systematic approach to selecting one lipid over another has been reported in the literature. In this study, propylene glycol (PG monoester (PG monocaprylate, Capmul PG-8® and PG diester (PG dicaprylocaprate, Captex 200P® of C8-fatty acids were compared with PG monoester (PG monolaurate, Capmul PG-12® and PG diester (PG dilaurate, Capmul PG-2L® of C12-fatty acids with respect to their phase diagrams, and especially for their ability to form microemulsions in the presence of a common surfactant, Cremophor EL®, and water. The solubility of two model drugs, danazol and probucol, in the lipids and lipid/surfactant mixtures were also compared. The effect of the chain length of medium-chain fatty acids (C8 versus C12 on the phase diagrams of the lipids was minimal. Both shorter and longer chain lipids formed essentially similar microemulsion and emulsion regions in the presence of Cremophor EL® and water, although the C12-fatty acid esters formed larger gel regions in the phase diagrams than the C8-fatty acid esters. When monoesters were mixed with their respective diesters at 1:1 ratios, larger microemulsion regions with lower lipid particle sizes were observed compared to those obtained with individual lipids alone. While the solubility of both danazol and probucol increased greatly in all lipids studied, compared to their aqueous solubility, the solubility in C12-fatty acid esters was found to be lower than in C8-fatty acid esters when the lipids were used alone. This difference in solubility due to the difference in fatty acid chain length, practically disappeared when the lipids were combined with the surfactant.

  8. Release of a Poorly Soluble Drug from Hydrophobically Modified Poly (Acrylic Acid in Simulated Intestinal Fluids.

    Directory of Open Access Journals (Sweden)

    Patrik Knöös

    Full Text Available A large part of new pharmaceutical substances are characterized by a poor solubility and high hydrophobicity, which might lead to a difference in drug adsorption between fasted and fed patients. We have previously evaluated the release of hydrophobic drugs from tablets based on Pemulen TR2 and showed that the release can be manipulated by adding surfactants. Here we further evaluate the possibility to use Pemulen TR2 in controlled release tablet formulations containing a poorly soluble substance, griseofulvin. The release is evaluated in simulated intestinal media that model the fasted state (FaSSIF medium or fed state (FeSSIF. The rheology of polymer gels is studied in separate experiments, in order to gain more information on possible interactions. The release of griseofulvin in tablets without surfactant varied greatly and the slowest release were observed in FeSSIF. Addition of SDS to the tablets eliminated the differences and all tablets showed a slow linear release, which is of obvious relevance for robust drug delivery. Comparing the data from the release studies and the rheology experiment showed that the effects on the release from the different media could to a large extent be rationalised as a consequence of the interactions between the polymer and the surfactants in the media. The study shows that Pemulen TR2 is a candidate for controlled release formulations in which addition of surfactant provides a way to eliminate food effects on the release profile. However, the formulation used needs to be designed to give a faster release rate than the tablets currently investigated.

  9. Structural and solubility parameter correlations of gelation abilities for dihydroxylated derivatives of long-chain, naturally occurring fatty acids.

    Science.gov (United States)

    Zhang, Mohan; Selvakumar, Sermadurai; Zhang, Xinran; Sibi, Mukund P; Weiss, Richard G

    2015-06-01

    Creating structure-property correlations at different distance scales is one of the important challenges to the rational design of molecular gelators. Here, a series of dihydroxylated derivatives of long-chain fatty acids, derived from three naturally occurring molecules-oleic, erucic and ricinoleic acids-are investigated as gelators of a wide variety of liquids. Conclusions about what constitutes a more (or less!) efficient gelator are based upon analyses of a variety of thermal, structural, molecular modeling, and rheological results. Correlations between the manner of molecular packing in the neat solid or gel states of the gelators and Hansen solubility data from the liquids leads to the conclusion that diol stereochemistry, the number of carbon atoms separating the two hydroxyl groups, and the length of the alkanoic chains are the most important structural parameters controlling efficiency of gel formation for these gelators. Some of the diol gelators are as efficient or even more efficient than the well-known, excellent gelator, (R)-12-hydroxystearic acid; others are much worse. The ability to form extensive intermolecular H-bonding networks along the alkyl chains appears to play a key role in promoting fiber growth and, thus, gelation. In toto, the results demonstrate how the efficiency of gelation can be modulated by very small structural changes and also suggest how other structural modifications may be exploited to create efficient gelators. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Histidine-functionalized water-soluble nanoparticles for biomimetic nucleophilic/general-base catalysis under acidic conditions.

    Science.gov (United States)

    Chadha, Geetika; Zhao, Yan

    2013-10-21

    Cross-linking the micelles of 4-dodecyloxybenzyltripropargylammonium bromide by 1,4-diazidobutane-2,3-diol in the presence of azide-functionalized imidazole derivatives yielded surface-cross-linked micelles (SCMs) with imidazole groups on the surface. The resulting water-soluble nanoparticles were found, by fluorescence spectroscopy, to contain hydrophobic binding sites. The imidazole groups promoted the photo-deprotonation of 2-naphthol at pH 6 and catalyzed the hydrolysis of p-nitrophenylacetate (PNPA) in aqueous solution at pH ≥ 4. Although the overall hydrolysis rate slowed down with decreasing solution pH, the catalytic effect of the imidazole became stronger because the reactions catalyzed by unfunctionalized SCMs slowed down much more. The unusual ability of the imidazole–SCMs to catalyze the hydrolysis of PNPA under acidic conditions was attributed to the local hydrophobicity and the positive nature of the SCMs.

  11. Phytase activity of lactic acid bacteria and their impact on the solubility of minerals from wholemeal wheat bread.

    Science.gov (United States)

    Cizeikiene, Dalia; Juodeikiene, Grazina; Bartkiene, Elena; Damasius, Jonas; Paskevicius, Algimantas

    2015-01-01

    The objective of this study was to determinate phytase activity of bacteriocins producing lactic acid bacteria previously isolated from spontaneous rye sourdough. The results show that the highest extracellular phytase activity produces Pediococcus pentosaceus KTU05-8 and KTU05-9 strains with a volumetric phytase activity of 32 and 54 U/ml, respectively, under conditions similar to leavening of bread dough (pH 5.5 and 30 °C). In vitro studies in simulated gastrointestinal tract media pH provide that bioproducts prepared with P. pentosaceus strains used in wholemeal wheat bread preparation increase solubility of iron, zinc, manganese, calcium and phosphorus average 30%. Therefore, P. pentosaceus KTU05-9 and KTU05-8 strains could be recommended to use as a starter for sourdough preparation for increasing of mineral bioavailability from wholemeal wheat bread.

  12. Kinetics of Corrosion Inhibition of Aluminum in Acidic Media by Water-Soluble Natural Polymeric Pectates as Anionic Polyelectrolyte Inhibitors.

    Science.gov (United States)

    Hassan, Refat M; Zaafarany, Ishaq A

    2013-06-17

    Corrosion inhibition of aluminum (Al) in hydrochloric acid by anionic polyeletrolyte pectates (PEC) as a water-soluble natural polymer polysaccharide has been studied using both gasometric and weight loss techniques. The results drawn from these two techniques are comparable and exhibit negligible differences. The inhibition efficiency was found to increase with increasing inhibitor concentration and decrease with increasing temperature. The inhibition action of PEC on Al metal surface was found to obey the Freundlich isotherm. Factors such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and temperature affecting the corrosion rates were examined. The kinetic parameters were evaluated and a suitable corrosion mechanism consistent with the kinetic results is discussed in the paper.

  13. Kinetics of Corrosion Inhibition of Aluminum in Acidic Media by Water-Soluble Natural Polymeric Pectates as Anionic Polyelectrolyte Inhibitors

    Directory of Open Access Journals (Sweden)

    Refat M. Hassan

    2013-06-01

    Full Text Available Corrosion inhibition of aluminum (Al in hydrochloric acid by anionic polyeletrolyte pectates (PEC as a water-soluble natural polymer polysaccharide has been studied using both gasometric and weight loss techniques. The results drawn from these two techniques are comparable and exhibit negligible differences. The inhibition efficiency was found to increase with increasing inhibitor concentration and decrease with increasing temperature. The inhibition action of PEC on Al metal surface was found to obey the Freundlich isotherm. Factors such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and temperature affecting the corrosion rates were examined. The kinetic parameters were evaluated and a suitable corrosion mechanism consistent with the kinetic results is discussed in the paper.

  14. Micropore surface area of alkali-soluble plant macromolecules (humic acids) drives their decomposition rates in soil.

    Science.gov (United States)

    Papa, Gabriella; Spagnol, Manuela; Tambone, Fulvia; Pilu, Roberto; Scaglia, Barbara; Adani, Fabrizio

    2010-02-01

    Previous studies suggested that micropore surface area (MSA) of alkali-soluble bio-macromolecules of aerial plant residues of maize constitutes an important factor that explains their humification in soil, that is, preservation against biological degradation. On the other hand, root plant residue contributes to the soil humus balance, as well. Following the experimental design used in a previous paper published in this journal, this study shows that the biochemical recalcitrance of the alkali-soluble acid-insoluble fraction of the root plant material, contributed to the root maize humification of both Wild-type maize plants and its corresponding mutant brown midrib (bm3), this latter characterized by reduced lignin content. Humic acids (HAs) existed in root (root-HAs) were less degraded in soil than corresponding HAs existed in shoot (shoot-HAs): shoot-HAs bm3 (48%)>shoot-HAs Wild-type (37%)>root-HAs Wild-type (33%)>root-HAs bm3 (22%) (degradability shown in parenthesis). These differences were related to the MSA of HAs, that is, root-HAs having a higher MSA than shoot-HAs: shoot-HAs bm3 (41.43+/-1.2m(2)g(-1))

  15. A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

    Science.gov (United States)

    Collins, John; Li, Xiaohong; Pletcher, Derek; Tangirala, Ravichandra; Stratton-Campbell, Duncan; Walsh, Frank C.; Zhang, Caiping

    Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm × 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%.

  16. A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Collins, John; Stratton-Campbell, Duncan [C-Tech Innovation Ltd., Capenhurst, Chester CH1 6EH (United Kingdom); Li, Xiaohong; Tangirala, Ravichandra; Walsh, Frank C.; Zhang, Caiping [Energy Technology Research Group, School of Engineering Sciences, University of Southampton, Highfield, University Road, Southampton SO17 1BJ (United Kingdom); Pletcher, Derek [Electrochemistry and Surface Science Group, School of Chemistry, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2010-05-01

    Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm x 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%. (author)

  17. Uncharged water-soluble porphyrin tweezers as a supramolecular sensor for α-amino acids

    International Nuclear Information System (INIS)

    Villari, Valentina; Mineo, Placido; Micali, Norberto; Angelini, Nicola; Vitalini, Daniele; Scamporrino, Emilio

    2007-01-01

    The binding between uncharged cobalt porphyrin tweezers and L-amino acids in aqueous solutions is studied by means of UV-vis and circular dichroism spectroscopy. By varying the length of the aliphatic bridge between the two porphyrin units, the number of cobalt ions in the porphyrin cores and the pH of the solution, the chirality induction phenomenon has been investigated. The binding of the amino acid to the porphyrin seems to occur via a coordination mechanism between the metal and the nitrogen of the amino group; the steric, hydrophobic and π-π interactions operate to stabilize the complexes. The chirogenesis displays an opposite behaviour in the presence of aromatic guests with respect to the non-aromatic ones. Moreover, the UV-vis and the induced circular dichroism spectral changes suggest that the amino acid arrangement in the tweezers is determined by many factors, so that, unlike in organic solvent, the porphyrin tweezers in aqueous solution allow for two different arrangements of the same aromatic amino acid. The experimental findings indicate that the porphyrins tweezers reported in the paper are promising in opening perspectives toward their application as a selective molecular sensor in aqueous solutions directly

  18. Redox potentials and kinetics of the Ce 3+/Ce 4+ redox reaction and solubility of cerium sulfates in sulfuric acid solutions

    Science.gov (United States)

    Paulenova, A.; Creager, S. E.; Navratil, J. D.; Wei, Y.

    Experimental work was performed with the aim of evaluating the Ce 4+/Ce 3+ redox couple in sulfuric acid electrolyte for use in redox flow battery (RFB) technology. The solubility of cerium sulfates in 0.1-4.0 M sulfuric acid at 20-60 °C was studied. A synergistic effect of both sulfuric acid concentration and temperature on the solubility of cerous sulfate was observed. The solubility of cerous sulfate significantly decreased with rising concentration of sulfuric acid and rising temperature, while the solubility of ceric sulfate goes through a significant maximum at 40 °C. Redox potentials and the kinetics of the cerous/ceric redox reaction were also studied under the same temperature-concentration conditions. The redox potentials were measured using the combined redox electrode (Pt-Ag/AgCl) in equimolar Ce 4+/Ce 3+ solutions (i.e.[Ce 3+]=[Ce 4+]) in sulfuric acid electrolyte. The Ce 3+/Ce 4+ redox potentials significantly decrease (i.e. shift to more negative values) with rising sulfuric acid concentration; a small maximum is observed at 40 °C. Cyclic voltammetric experiments confirmed slow electrochemical kinetics of the Ce 3+/Ce 4+ redox reaction on carbon glassy electrodes (CGEs) in sulfuric acid solutions. The observed dependencies of solubilities, the redox potentials and the kinetics of Ce 3+/Ce 4+ redox reaction on sulfuric acid concentration are thought to be the result of inequivalent complexation of the two redox species by sulfate anions: the ceric ion is much more strongly bound to sulfate than is the cerous ion. The best temperature-concentration conditions for the RFB electrolytes appear to be 40 °C and 1 M sulfuric acid, where the relatively good solubility of both cerium species, the maximum of redox potentials, and the more or less satisfying stability of CGE s were found. Even so, the relatively low solubility of cerium salts in sulfuric acid media and slow redox kinetics of the Ce 3+/Ce 4+ redox reaction at carbon indicate that the Ce 3+/Ce

  19. A new synthetic methodology for the preparation of biocompatible and organo-soluble barbituric- and thiobarbituric acid based chitosan derivatives for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Shahzad, Sohail [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Shahzadi, Lubna [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Mahmood, Nasir [Department of Allied Health Sciences and Chemical Pathology, Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore (Pakistan); Siddiqi, Saadat Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rauf, Abdul [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Manzoor, Faisal; Chaudhry, Aqif Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rehman, Ihtesham ur [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Materials Science and Engineering, The Kroto Research Institute, The University of Sheffield, North Campus, Broad Lane, Sheffield, S3 7HQ (United Kingdom); Yar, Muhammad, E-mail: drmyar@ciitlahore.edu.pk [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan)

    2016-09-01

    Chitosan's poor solubility especially in organic solvents limits its use with other organo-soluble polymers; however such combinations are highly required to tailor their properties for specific biomedical applications. This paper describes the development of a new synthetic methodology for the synthesis of organo-soluble chitosan derivatives. These derivatives were synthesized from chitosan (CS), triethyl orthoformate and barbituric or thiobarbituric acid in the presence of 2-butannol. The chemical interactions and new functional motifs in the synthesized CS derivatives were evaluated by FTIR, DSC/TGA, UV/VIS, XRD and {sup 1}H NMR spectroscopy. A cytotoxicity investigation for these materials was performed by cell culture method using VERO cell line and all the synthesized derivatives were found to be non-toxic. The solubility analysis showed that these derivatives were readily soluble in organic solvents including DMSO and DMF. Their potential to use with organo-soluble commercially available polymers was exploited by electrospinning; the synthesized derivatives in combination with polycaprolactone delivered nanofibrous membranes. - Highlights: • Development of a new synthetic methodology • Synthesis of organo-soluble chitosan (CS) derivatives • VERO cells proliferation • Nanofibrous membranes from the synthesized chitosan derivatives and polycaprolactone.

  20. Dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs with poor water solubility.

    Science.gov (United States)

    Tran, Phuong Ha-Lien; Tran, Thao Truong-Dinh; Lee, Kyoung-Ho; Kim, Dong-Jin; Lee, Beom-Jin

    2010-05-01

    Although the solid dispersion method has been known to increase the dissolution rate of poorly water-soluble drugs by dispersing them in hydrophilic carriers, one obstacle of the solid dispersion method is its limited solubilization capacity, especially for pH-dependent soluble drugs. pH-modified solid dispersion, in which pH modifiers are incorporated, may be a useful method for increasing the dissolution rate of weakly acidic or basic drugs. Sufficient research, including the most recent reports, was undertaken in this review. How could the inclusion of the pH the pH modifiers in the solid dispersion system change drug structural behaviors, molecular interactions, microenvironmental pH, and/or release rate of pH modifiers, relating with the enhanced dissolution of weakly acidic or weakly basic drugs with poor water solubility? These questions have been investigated to determine the dissolution-modulating mechanism of pH modifiers in solid dispersion containing weakly acidic or basic drugs. It is believed that step-by-step mechanistic approaches could provide the ultimate solution for solubilizing several poorly water-soluble drugs with pH-dependent solubility from a solid dispersion system, as well as provide ideas for developing future dosage systems.

  1. Incorporation of Mg and Ca into nanostructured Fe2O3 improves Fe solubility in dilute acid and sensory characteristics in foods.

    Science.gov (United States)

    Hilty, Florentine M; Knijnenburg, Jesper T N; Teleki, Alexandra; Krumeich, Frank; Hurrell, Richard F; Pratsinis, Sotiris E; Zimmermann, Michael B

    2011-01-01

    Iron deficiency is one of the most common micronutrient deficiencies worldwide. Food fortification can be an effective and sustainable strategy to reduce Fe deficiency but selection of iron fortificants remains a challenge. Water-soluble compounds, for example, FeSO(4), usually demonstrate high bioavailability but they often cause unacceptable sensory changes in foods. On the other hand, poorly acid-soluble Fe compounds, for example FePO(4), may cause fewer adverse sensory changes in foods but are usually not well bioavailable since they need to be dissolved in the stomach prior to absorption. The solubility and the bioavailability of poorly acid-soluble Fe compounds can be improved by decreasing their primary particle size and thereby increasing their specific surface area. Here, Fe oxide-based nanostructured compounds with added Mg or Ca were produced by scalable flame aerosol technology. The compounds were characterized by nitrogen adsorption, X-ray diffraction, transmission electron microscopy, and Fe solubility in dilute acid. Sensory properties of the Fe-based compounds were tested in 2 highly reactive, polyphenol-rich food matrices: chocolate milk and fruit yoghurt. The Fe solubility of nanostructured Fe(2)O(3) doped with Mg or Ca was higher than that of pure Fe(2)O(3). Since good solubility in dilute acid was obtained despite the inhomogeneity of the powders, inexpensive precursors, for example Fe- and Ca-nitrates, can be used for their manufacture. Adding Mg or Ca lightened powder color, while sensory changes when added to foods were less pronounced than for FeSO(4). The combination of high Fe solubility and low reactivity in foods makes these flame-made nanostructured compounds promising for food fortification. Practical Application: The nanostructured iron-containing compounds presented here may prove useful for iron fortification of certain foods; they are highly soluble in dilute acid and likely to be well absorbed in the gut but cause less severe

  2. Effect of Citric Acid Surface Modification on Solubility of Hydroxyapatite Nanoparticles.

    Science.gov (United States)

    Samavini, Ranuri; Sandaruwan, Chanaka; De Silva, Madhavi; Priyadarshana, Gayan; Kottegoda, Nilwala; Karunaratne, Veranja

    2018-04-04

    Worldwide, there is an amplified interest in nanotechnology-based approaches to develop efficient nitrogen, phosphorus, and potassium fertilizers to address major challenges pertaining to food security. However, there are significant challenges associated with fertilizer manufacture and supply as well as cost in both economic and environmental terms. The main issues relating to nitrogen fertilizer surround the use of fossil fuels in its production and the emission of greenhouse gases resulting from its use in agriculture; phosphorus being a mineral source makes it nonrenewable and casts a shadow on its sustainable use in agriculture. This study focuses on development of an efficient P nutrient system that could overcome the inherent problems arising from current P fertilizers. Attempts are made to synthesize citric acid surface-modified hydroxyapatite nanoparticles using wet chemical precipitation. The resulting nanohybrids were characterized using powder X-ray diffraction to extract the crystallographic data, while functional group analysis was done by Fourier transform infrared spectroscopy. Morphology and particle size were studied using scanning electron microscopy along with elemental analysis using energy-dispersive X-ray diffraction spectroscopy. Its effectiveness as a source of P was investigated using water release studies and bioavailability studies using Zea mays as the model crop. Both tests demonstrated the increased availability of P from nanohybrids in the presence of an organic acid compared with pure hydroxyapatite nanoparticles and rock phosphate.

  3. Enthalpy-entropy compensation for the solubility of drugs in solvent mixtures: paracetamol, acetanilide, and nalidixic acid in dioxane-water.

    Science.gov (United States)

    Bustamante, P; Romero, S; Pena, A; Escalera, B; Reillo, A

    1998-12-01

    In earlier work, a nonlinear enthalpy-entropy compensation was observed for the solubility of phenacetin in dioxane-water mixtures. This effect had not been earlier reported for the solubility of drugs in solvent mixtures. To gain insight into the compensation effect, the behavior of the apparent thermodynamic magnitudes for the solubility of paracetamol, acetanilide, and nalidixic acid is studied in this work. The solubility of these drugs was measured at several temperatures in dioxane-water mixtures. DSC analysis was performed on the original powders and on the solid phases after equilibration with the solvent mixture. The thermal properties of the solid phases did not show significant changes. The three drugs display a solubility maximum against the cosolvent ratio. The solubility peaks of acetanilide and nalidixic acid shift to a more polar region at the higher temperatures. Nonlinear van't Hoff plots were observed for nalidixic acid whereas acetanilide and paracetamol show linear behavior at the temperature range studied. The apparent enthalpies of solution are endothermic going through a maximum at 50% dioxane. Two different mechanisms, entropy and enthalpy, are suggested to be the driving forces that increase the solubility of the three drugs. Solubility is entropy controlled at the water-rich region (0-50% dioxane) and enthalpy controlled at the dioxane-rich region (50-100% dioxane). The enthalpy-entropy compensation analysis also suggests that two different mechanisms, dependent on cosolvent ratio, are involved in the solubility enhancement of the three drugs. The plots of deltaH versus deltaG are nonlinear, and the slope changes from positive to negative above 50% dioxane. The compensation effect for the thermodynamic magnitudes of transfer from water to the aqueous mixtures can be described by a common empirical nonlinear relationship, with the exception of paracetamol, which follows a separate linear relationship at dioxane ratios above 50%. The

  4. Amino acid digestibility of corn distillers dried grains with solubles, liquid condensed solubles, pulse dried thin stillage, and syrup balls fed to growing pigs.

    Science.gov (United States)

    Soares, J A; Stein, H H; Singh, V; Shurson, G S; Pettigrew, J E

    2012-04-01

    Distillers dried grains with solubles (DDGS) has low and variable AA digestibility. The variability is often attributed to damage during the heating process, and it has been suggested that the damage happens to the soluble components of DDGS such as reducing sugars. Combining solubles and grains sometimes produces syrup balls (SB); their digestibility is unknown. The objective of this experiment was to identify potential sources of poor and variable AA digestibility in DDGS. Specifically, our objective was to determine whether the problems are associated with the solubles component or with SB. The ingredients evaluated were DDGS, intact SB, ground SB, liquid condensed solubles (LCS), and pulse dried thin stillage (PDTS) obtained from the same ethanol plant. The LCS is produced by evaporation of thin stillage. Each ingredient was used as the only source of AA in an experimental diet. In a duplicate 6 × 6 Latin square design with 7-d adaptation and collection periods, the 6 treatments consisted of an N-free diet and the 5 test ingredients. Pigs had 5 d of adaptation to each diet, and on d 6 and 7 ileal digesta were collected from an ileal cannula for 8 h each day. Both SB treatments had apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA that were similar or greater (P < 0.05) than those of DDGS. The AID and SID values of Lys and a few other AA were similar in LCS (SID Lys: 63.1%) and DDGS (SID Lys: 61.5%), but the digestibility values of most AA in LCS were less than in DDGS (P < 0.05). The low digestibility of AA in LCS was most pronounced for Met (SID: LCS, 41.9% vs. DDGS, 82.8%). The LCS had less (P < 0.05) AID and SID of CP (SID: 67.8%) than intact SB (SID: 85.2%) and ground SB (SID: 85.9%) as well as all AA. The PDTS generally had the least AID and SID and had less (P < 0.05) CP (SID: 55.3%) and several AA, including Lys, compared with LCS. In conclusion, the presence of SB does not decrease AA digestibility of DDGS, and the LCS

  5. Electrochemical characterization of mixed self-assembled films of water-soluble single-walled carbon nanotube-poly(m-aminobenzene sulfonic acid) and Iron(II) tetrasulfophthalocyanine

    CSIR Research Space (South Africa)

    Agboola, BO

    2010-09-01

    Full Text Available The redox activities of water-soluble iron(II) tetrasulfophthalocyanine (FeTSPc) and single-walled carbon nanotube-poly(m-aminobenzene sulfonic acid) (SWCNT-PABS) adsorbed on a gold surface precoated with a self-assembled monolayer (SAM) of 2...

  6. Decreased UV light resistance of spores of Bacillus subtilis strains deficient in pyrimidine dimer repair and small, acid-soluble spore proteins

    International Nuclear Information System (INIS)

    Setlow, B.; Setlow, P.

    1988-01-01

    Loss of small, acid-soluble spore protein alpha reduced spore UV resistance 30- to 50-fold in Bacillus subtilis strains deficient in pyrimidine dimer repair, but gave only a 5- to 8-fold reduction in UV resistance in repair-proficient strains. However, both repair-proficient and -deficient spores lacking this protein had identical heat and gamma-radiation resistance

  7. Release of Water Soluble Drugs from Dynamically Swelling POLY(2-HYDROXYETHYL Methacrylate - CO - Methacrylic Acid) Hydrogels.

    Science.gov (United States)

    Kou, Jim Hwai-Cher

    In this study, ionizable copolymers of HEMA and methacrylic acid (MA) are investigated for their potential use in developing pH dependent oral delivery systems. Because of the MA units, these gels swell extensively at high pH. Since solute diffusion in the hydrophilic polymers depends highly on the water content of the matrix, it is anticipated that the release rate will be modulated by this pH induced swelling. From a practical point of view, the advantage of the present system is that one can minimize drug loss in the stomach and achieve a programmed release in intestine. This approach is expected to improve delivery of acid labile drugs or drugs that cause severe gastrointestinal side effects. This work mainly focuses on the basic understanding of the mechanism involved in drug release from the poly(HEMA -co- MA) gels, especially under dynamic swelling conditions. Equilibrium swelling is first characterized since water content is the major determinant of transport properties in these gels. Phenylpropanolamine (PPA) is chosen as the model drug for the release study and its diffusion characteristics in the gel matrix determined. The data obtained show that the PPA diffusivity follows the free volume theory of Yasuda, which explains the accelerating effect of swelling on drug release. A mathematical model based on a diffusion mechanism has been developed to describe PPA release from the swelling gels. Based on this model, several significant conclusions can be drawn. First, the release rate can be modulated by the aspect ratio of the cylindrical geometry, and this has a practical implication in dosage form design. Second, the release rate can be lowered quite considerably if the dimensional increase due to swelling is significant. Consequently, it is the balance between the drug diffusivity increase and the gel dimensional growth that determines the release rate from the swelling matrix. Third, quasi-steady release kinetics, which are characteristic of swelling

  8. Chemical modeling of acid-base properties of soluble biopolymers derived from municipal waste treatment materials.

    Science.gov (United States)

    Tabasso, Silvia; Berto, Silvia; Rosato, Roberta; Marinos, Janeth Alicia Tafur; Ginepro, Marco; Zelano, Vincenzo; Daniele, Pier Giuseppe; Montoneri, Enzo

    2015-02-04

    This work reports a study of the proton-binding capacity of biopolymers obtained from different materials supplied by a municipal biowaste treatment plant located in Northern Italy. One material was the anaerobic fermentation digestate of the urban wastes organic humid fraction. The others were the compost of home and public gardening residues and the compost of the mix of the above residues, digestate and sewage sludge. These materials were hydrolyzed under alkaline conditions to yield the biopolymers by saponification. The biopolymers were characterized by 13C NMR spectroscopy, elemental analysis and potentiometric titration. The titration data were elaborated to attain chemical models for interpretation of the proton-binding capacity of the biopolymers obtaining the acidic sites concentrations and their protonation constants. The results obtained with the models and by NMR spectroscopy were elaborated together in order to better characterize the nature of the macromolecules. The chemical nature of the biopolymers was found dependent upon the nature of the sourcing materials.

  9. Epoxy fatty acids and inhibition of the soluble epoxide hydrolase selectively modulate GABA mediated neurotransmission to delay onset of seizures.

    Directory of Open Access Journals (Sweden)

    Bora Inceoglu

    Full Text Available In the brain, seizures lead to release of large amounts of polyunsaturated fatty acids including arachidonic acid (ARA. ARA is a substrate for three major enzymatic routes of metabolism by cyclooxygenase, lipoxygenase and cytochrome P450 enzymes. These enzymes convert ARA to potent lipid mediators including prostanoids, leukotrienes and epoxyeicosatrienoic acids (EETs. The prostanoids and leukotrienes are largely pro-inflammatory molecules that sensitize neurons whereas EETs are anti-inflammatory and reduce the excitability of neurons. Recent evidence suggests a GABA-related mode of action potentially mediated by neurosteroids. Here we tested this hypothesis using models of chemically induced seizures. The level of EETs in the brain was modulated by inhibiting the soluble epoxide hydrolase (sEH, the major enzyme that metabolizes EETs to inactive molecules, by genetic deletion of sEH and by direct administration of EETs into the brain. All three approaches delayed onset of seizures instigated by GABA antagonists but not seizures through other mechanisms. Inhibition of neurosteroid synthesis by finasteride partially blocked the anticonvulsant effects of sEH inhibitors while the efficacy of an inactive dose of neurosteroid allopregnanolone was enhanced by sEH inhibition. Consistent with earlier findings, levels of prostanoids in the brain were elevated. In contrast, levels of bioactive EpFAs were decreased following seizures. Overall these results demonstrate that EETs are natural molecules which suppress the tonic component of seizure related excitability through modulating the GABA activity and that exploration of the EET mediated signaling in the brain could yield alternative approaches to treat convulsive disorders.

  10. Solubility and phase separation of 4-morpholinepropanesulfonic acid (MOPS), and 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO) in aqueous 1,4-dioxane and ethanol solutions

    International Nuclear Information System (INIS)

    Taha, Mohamed; Lee, Ming-Jer

    2011-01-01

    Highlights: → Solubilities of MOPS and MOPSO buffers in aqueous 1,4-dioxane and ethanol solutions. → We found that MOPS-induced phase separation of aqueous solution of 1,4-dioxane. → The phase diagram of (MOPS + water + 1,4-dioxane) system at 298.15 K is documented. → The tie-lines within the two-liquid phase region were also determined at 298.15 K. → The effective excluded volume theory was applied to correlate the binodal LLE data. - Abstract: The buffers 4-morpholinepropanesulfonic acid (MOPS) and 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO) are useful biological zwitterionic buffers within the pH range of 6.5 to 7.9 and 6.2 to 7.6, respectively. The solubilities of these buffers were determined in binary mixtures (1,4-dioxane + water) and (ethanol + water) at T = 298.15 K by using the results of density measurements. It has been observed that MOPS induced liquid-liquid phase splitting for the mixtures of 40% to 90% (w/w) 1,4-dioxane in water. The two-liquid phase formation was visualized with disperse orange 25. The phase equilibrium boundaries, including the regions of one liquid, two liquids, (one liquid + one solid) and (two liquids + one solid), for the (MOPS + water + 1,4-dioxane) system have been determined experimentally at T = 298.15 K. The tie lines of the (liquid + liquid) equilibrium were also measured. The Othmer-Tobias and Bancroft equation were used to evaluate the reliability of the tie-line data. The binodal curve was fitted to an empirical equation and the effective excluded volume (EEV) model. The apparent free energies of transfer (ΔG tr ' ) of MOPS and MOPSO from water to 1,4-dioxane and ethanol solutions have been calculated from the solubility data. These ΔG tr ' values were compared with those of some related biological buffers (TRIS, TAPS, TAPSO, and TABS). Furthermore, we also calculated the contribution of transfer free energies (Δg tr ' ) of -OH group from water to 1,4-dioxane and ethanol solutions.

  11. Chemical Modeling of Acid-Base Properties of Soluble Biopolymers Derived from Municipal Waste Treatment Materials

    Directory of Open Access Journals (Sweden)

    Silvia Tabasso

    2015-02-01

    Full Text Available This work reports a study of the proton-binding capacity of biopolymers obtained from different materials supplied by a municipal biowaste treatment plant located in Northern Italy. One material was the anaerobic fermentation digestate of the urban wastes organic humid fraction. The others were the compost of home and public gardening residues and the compost of the mix of the above residues, digestate and sewage sludge. These materials were hydrolyzed under alkaline conditions to yield the biopolymers by saponification. The biopolymers were characterized by 13C NMR spectroscopy, elemental analysis and potentiometric titration. The titration data were elaborated to attain chemical models for interpretation of the proton-binding capacity of the biopolymers obtaining the acidic sites concentrations and their protonation constants. The results obtained with the models and by NMR spectroscopy were elaborated together in order to better characterize the nature of the macromolecules. The chemical nature of the biopolymers was found dependent upon the nature of the sourcing materials.

  12. Behavior of soluble and immobilized acid phosphatase in hydro-organic media.

    Science.gov (United States)

    Wan, H; Horvath, C

    1975-11-20

    The hydrolysis of p-nitrophenyl phosphate by wheat germ acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) has been investigated in mixtures of aqueous buffers with acetone, dioxane and acetonitrile. The enzyme was either in free solution or immobilized on a pellicular support which consisted of a porous carbonaceous layer on solid glass beads. The highest enzyme activity was obtained in acetone and acetonitrile mixed with citrate buffer over a wide range of organic solvent concentration. In 50% (v/v) acetone both V and Km of the immobilized enzyme were about half of the values in the neat aqueous buffer, but the Ki for inorganic phosphate was unchanged. In 50% (v/v) mixtures of various solvents and citrate buffers of different pH, the enzymic activity was found to depend on the pH of the aqueous buffer component rather than the pH of the hydro-organic mixture as measured with the glass-calomel electrode. The relatively high rates of p-nitrophenol liberation in the presence of glucose even at high organic solvent concentrations suggest that transphosphorylation is facilitated at low water activity.

  13. Biocompatible Water Soluble Polyacrylic Acid Coated CdSe/Cu Quantum Dot Conjugates for Biomolecule Detection.

    Science.gov (United States)

    Gomaa, Ola M; Okasha, Aly; Hosni, Hany M; El-Hag Ali, Amr

    2018-01-01

    Biocompatible polyacrylic acid functionalized CdSe/Cu quantum dot conjugates were synthesized to be used for biomolecules detection. The study results demonstrate the conjugation of the 2.5-3 nm QD with gram negative bacteria with a low detection limit of 28 cfu/ml. The photoluminescence (PL) intensity was correlated to bacterial count, cellular proteins and exopolysaccharides in the tested samples. Confocal Scanning Laser Microscopy (CSLM) images showed significant QD uptake within the cells, both cytoplasm and DNA were the predominant targeted biomolecules, higher fluorescent uptake was shown in gram negative bacteria than that observed for gram positive bacteria. Moreover, PL showed that there was a distinction between live and dead cells as well as gram negative and gram positive cells. Cell viability was not affected even after 6 days (100% viability) rendering it a non-toxic QD. The method is simple and is performed in a single step within approximately 10 min as compared to multi-step protocols for classical microbial count or fluorescent dye staining. All the above results indicate that the CdSe/Cu-PAA QDs are suitable for biomolecule detection, bio-labeling and bioimaging applications.

  14. Structural Characterization of Febuxostat/l-Pyroglutamic Acid Cocrystal Using Solid-State 13C-NMR and Investigational Study of Its Water Solubility

    OpenAIRE

    Ji-Hun An; Changjin Lim; Hyung Chul Ryu; Jae Sun Kim; Hyuk Min Kim; Alice Nguvoko Kiyonga; Minho Park; Young-Ger Suh; Gyu Hwan Park; Kiwon Jung

    2017-01-01

    Febuxostat (FB) is a poorly water-soluble drug that belongs to BCS class II. The drug is employed for the treatment of inflammatory disease arthritis urica (gout), and the free base, FB form-A, is most preferred for drug formulation. In order to achieve a goal of improving the water solubility of FB form-A, this study was carried out using the cocrystallization technique called the liquid-assisted grinding method to produce FB cocrystals. Here, five amino acids containing amine (NH), oxygen (...

  15. Production of a water-soluble fertilizer containing amino acids by solid-state fermentation of soybean meal and evaluation of its efficacy on the rapeseed growth.

    Science.gov (United States)

    Wang, Jianlei; Liu, Zhemin; Wang, Yue; Cheng, Wen; Mou, Haijin

    2014-10-10

    Soybean meal is a by-product of soybean oil extraction and contains approximately 44% protein. We performed solid-state fermentation by using Bacillus subtilis strain N-2 to produce a water-soluble fertilizer containing amino acids. Strain N-2 produced a high yield of protease, which transformed the proteins in soybean meal into peptide and free amino acids that were dissolved in the fermentation products. Based on the Plackett-Burman design, the initial pH of the fermentation substrate, number of days of fermentation, and the ratio of liquid to soybean meal exhibited significant effects on the recovery of proteins in the resulting water-soluble solution. According to the predicted results of the central composite design, the highest recovery of soluble proteins (99.072%) was achieved at the optimum conditions. Under these conditions, the resulting solution contained 50.42% small peptides and 7.9% poly-γ-glutamic acid (γ-PGA). The water-soluble fertilizer robustly increased the activity of the rapeseed root system, chlorophyll content, leaf area, shoot dry weight, root length, and root weight at a concentration of 0.25% (w/v). This methodology offers a value-added use of soybean meal. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. The water soluble composite poly(vinylpyrrolidone–methylaniline: A new class of corrosion inhibitors of mild steel in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    R. Karthikaiselvi

    2017-02-01

    Full Text Available In recent years poly methyl aniline has been reported as one of the efficient corrosion inhibitors of mild steel in acidic media. In view of the major limitation of the insolubility of polymethyl aniline PMA, we propose to convert PMA into a water soluble composite using supporting polymer polyvinylpyrrolidone to get higher solubility and corrosion inhibition efficiency. The water soluble composite poly(vinylpyrrolidone-methyl aniline was synthesized by chemical oxidative polymerization and its inhibitive effect on mild steel in 1 M HCl has been investigated using weight loss and electrochemical techniques (potentiodynamic polarization studies and impedance spectroscopy. SEM and EDX analyses are carried out to establish a protective film formation on the metal surface.

  17. Combined Measurement of 6 Fat-Soluble Vitamins and 26 Water-Soluble Functional Vitamin Markers and Amino Acids in 50 μL of Serum or Plasma by High-Throughput Mass Spectrometry.

    Science.gov (United States)

    Midttun, Øivind; McCann, Adrian; Aarseth, Ove; Krokeide, Marit; Kvalheim, Gry; Meyer, Klaus; Ueland, Per M

    2016-11-01

    Targeted metabolic profiling characterized by complementary platforms, multiplexing and low volume consumption are increasingly used for studies using biobank material. Using liquid-liquid extraction, we developed a sample workup suitable for quantification of 6 fat- and 26 water-soluble biomarkers. 50 μL of serum/plasma was mixed with dithioerythritol, ethanol, and isooctane/chloroform. The organic layer was used for analysis of the fat-soluble vitamins all-trans retinol (A), 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, α-tocopherol (E), γ-tocopherol (E), and phylloquinone (K1) by LC-MS/MS. The remaining aqueous fraction was mixed with ethanol, water, pyridine, and methylchloroformate (in toluene) to derivatize the water-soluble biomarkers. The resulting toluene layer was used for GC-MS/MS analysis of alanine, α-ketoglutarate, asparagine, aspartic acid, cystathionine, total cysteine, glutamic acid, glutamine, glycine, histidine, total homocysteine, isoleucine, kynurenine, leucine, lysine, methionine, methylmalonic acid, ornithine, phenylalanine, proline, sarcosine, serine, threonine, tryptophan, tyrosine, and valine. Isotope-labeled internal standards were used for all analytes. Chromatographic run times for the LC-MS/MS and GC-MS/MS were 4.5 and 11 min, respectively. The limits of detection (LOD) for the low-concentration analytes (25-hydroxyvitamin D2, 25-hydroxyvitamin D3, and phylloquinone) were 25, 17, and 0.33 nM, respectively, while all other analytes demonstrated sensitivity significantly lower than endogenous concentrations. Recoveries ranged from 85.5-109.9% and within- and between-day coefficients of variance (CVs) were 0.7-9.4% and 1.1-17.5%, respectively. This low-volume, high-throughput multianalyte assay is currently in use in our laboratory for quantification of 32 serum/plasma biomarkers in epidemiological studies.

  18. In vitro solubility of calcium, iron and zinc in relation to phytic acid levels in rice-based consumer products in China.

    Science.gov (United States)

    Liang, Jianfen; Han, Bei-Zhong; Nout, M J Robert; Hamer, Robert J

    2010-02-01

    In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and [PA]/[Fe] and [PA]/[Zn] similarly ranged between 5 and 74, with most values between 20 and 30. [PA]/[mineral] molar ratios in intensively processed products were lower. Solubility of calcium ranged from 0% to 87%, with the lowest in brown rice (12%) and the highest in infant foods (50%). Iron solubility in two-thirds of samples was lower than 30%, and that of zinc narrowly ranged from 6% to 30%. Solubility of minerals was not significantly affected by [PA]/[mineral]. At present, neither primary nor intensively processed rice-based products are good dietary sources of minerals. Improvements should be attempted by dephytinization, mineral fortification or, preferably, combination of both.

  19. Determination of solubility isotherms of barium and strontium nitrates in the system acetic acid-water at 25/sup 0/ C

    Energy Technology Data Exchange (ETDEWEB)

    Hubicki, W.; Piskorek, M. (Uniwersytet Marii Curie-Sklodowskiej, Lublin (Poland))

    1976-01-01

    Investigations of the solubility of barium and strontium nitrates were carried out in the system: acetic acid - water at 25/sup 0/ C. When one compares the isotherms of solubility of barium and strontium nitrates, one can observe that it is possible to separate the admixtures of barium from strontium nitrates as a result of fractional crystallization of these nitrates from actic acid solution at the temperatures lower than 31.3/sup 0/ C, i.e. below the temperature of transformation: Sr(NO/sub 3/)/sub 2/ . 4H/sub 2/O reversible to Sr(NO/sub 3/)/sub 2/ + 4H/sub 2/O for aqueous solution.

  20. The effect of ammonium sulfate on the solubility of amino acids in water at (298.15 and 323.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Luisa A.; Macedo, Eugenia A. [Laboratory of Separation and Reaction Engineering, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Pinho, Simao P. [Laboratory of Separation and Reaction Engineering, Departamento de Tecnologia Quimica e Biologica, Instituto Politecnico de Braganca, Campus e Santa Apolonia, 5301-857 Braganca (Portugal)], E-mail: spinho@ipb.pt

    2009-02-15

    Using the analytical gravimetric method the solubility of glycine, DL-alanine, L-isoleucine, L-threonine, and L-serine in aqueous systems of (NH{sub 4}){sub 2}SO{sub 4}, at (298.15 and 323.15) K, were measured for salt concentrations ranging up to 2.0 molal. In the electrolyte molality range studied the experimental observations showed that ammonium sulfate is a salting-in agent for most of the amino acids studied. Furthermore, the change of the relative solubility with electrolyte concentration shows a maximum, which makes the representation of the data by a simple empirical correlation such as the Setschenow equation difficult. For the development and evaluation of a robust thermodynamic framework that makes it possible to more profoundly understand aqueous amino acid solutions with ammonium sulfate additional experimental information is needed.

  1. Senior high school students’ need analysis of Three-Tier Multiple Choice (3TMC) diagnostic test about acid-base and solubility equilibrium

    Science.gov (United States)

    Ardiansah; Masykuri, M.; Rahardjo, S. B.

    2018-05-01

    Students’ conceptual understanding is the most important comprehension to obtain related comprehension. However, they held their own conception. With this need analysis, we will elicit student need of 3TMC diagnostic test to measure students’ conception about acid-base and solubility equilibrium. The research done by a mixed method using questionnaire analysis based on descriptive of quantitative and qualitative. The research subject was 96 students from 4 senior high schools and 4 chemistry teachers chosen by random sampling technique. Data gathering used a questionnaire with 10 questions for student and 28 questions for teachers. The results showed that 97% of students stated that the development this instrument is needed. In addition, there were several problems obtained in this questionnaire include learning activity, teacher’s test and guessing. In conclusion, this is necessary to develop the 3TMC instrument that can diagnose and measure the student’s conception in acid-base and solubility equilibrium.

  2. Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells

    Energy Technology Data Exchange (ETDEWEB)

    Albertoni, G.; Schor, N. [Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2014-10-24

    Resveratrol (Resv) is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA) in immortalized human mesangial cells (ihMCs). ihMCs were preincubated with Resv (12.5 µM) for 1 h and treated with UA (10 mg/dL) for 6 or 12 h. The intracellular calcium concentration [Ca{sup 2+}]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT) and pre-pro endothelin-1 (ppET-1) mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII) and endothelin-1 (ET-1) were assayed by ELISA. UA significantly increased [Ca{sup 2+}]i. Pre-incubation with Resv significantly reduced the change in [Ca{sup 2+}]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca{sup 2+}]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells.

  3. Short communication: Effect of conjugated linoleic acid on concentrations of fat-soluble vitamins in milk of lactating ewes.

    Science.gov (United States)

    Zeitz, J O; Most, E; Eder, K

    2015-10-01

    Conjugated linoleic acids (CLA) are well known as milk fat-reducing feed supplements in diets for lactating ruminants. However, their effects on milk concentrations of fat-soluble vitamins are unknown. This study was performed to investigate the hypothesis that CLA affect the concentrations of retinol and tocopherol in ewe milk. For that purpose, group-housed Merino ewes (101 ± 13.7 kg) nursing twin lambs and fed with a hay:concentrate diet were supplemented with either 45 g of a rumen-protected CLA supplement containing 3.4 g of cis-9,trans-11-CLA and 3.4 g of trans-10,cis-12-CLA (CLA group, n=11) or with 45 g of a hydrogenated vegetable fat (control group, n=12) per ewe per day during the first 6 wk of lactation. Feed intake was recorded daily (concentrate) or weekly (hay) per group. Milk spot samples were collected at the beginning of the experiment (5 ± 2.4 d postpartum) and then weekly after lambs had been separated for 2 h from their mothers. The milk fat content was determined and feed and milk were analyzed for concentrations of α-, γ-, and δ-tocopherol and for retinol by HPLC. Dietary intake of tocopherol and retinol was similar in both groups. Feeding CLA decreased milk fat concentration by 23% on average, and during the first 3 wk of the study milk tocopherol concentration tended to be increased by feeding CLA (+17%), but retinol concentrations were not influenced. When related to milk fat, CLA feeding significantly increased both milk tocopherol (+40%) and retinol (+32%) and these effects were evident during the whole experimental period corresponding to the first half of lactation. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. On the americium oxalate solubility

    International Nuclear Information System (INIS)

    Zakolupin, S.A.; Korablin, Eh.V.

    1977-01-01

    The americium oxalate solubility at different nitric (0.0-1 M) and oxalic (0.0-0.4 M) acid concentrations was investigated in the temperature range from 14 to 60 deg C. The dependence of americium oxalate solubility on the oxalic acid concentration was determined. Increasing oxalic acid concentration was found to reduce the americium oxalate solubility. The dependence of americium oxalate solubility on the oxalic acid concentration was noted to be a minimum at low acidity (0.1-0.3 M nitric acid). This is most likely due to Am(C 2 O 4 ) + , Am(C 2 O 4 ) 2 - and Am(C 2 O 4 ) 3 3- complex ion formation which have different unstability constants. On the basis of the data obtained, a preliminary estimate was carried out for the product of americium oxalate solubility in nitric acid medium (10 -29 -10 -31 ) and of the one in water (6.4x10 -20 )

  5. Investigation on the Solubility of GaN in Supercritical Ammonia Containing Acidic, Neutral, and Some Basic Mineralizers

    National Research Council Canada - National Science Library

    Ehrentraut, Dirk

    2009-01-01

    ... material due to the superior structural quality over HVPE GaN. In order to hold up with the progress, not at least provide a scientific platform, the solubility of GaN in supercritical ammonia (NH3...

  6. Core-shell nanofibers of curcumin/cyclodextrin inclusion complex and polylactic acid: Enhanced water solubility and slow release of curcumin.

    Science.gov (United States)

    Aytac, Zeynep; Uyar, Tamer

    2017-02-25

    Core-shell nanofibers were designed via electrospinning using inclusion complex (IC) of model hydrophobic drug (curcumin, CUR) with cyclodextrin (CD) in the core and polymer (polylactic acid, PLA) in the shell (cCUR/HPβCD-IC-sPLA-NF). CD-IC of CUR and HPβCD was formed at 1:2 molar ratio. The successful formation of core-shell nanofibers was revealed by TEM and CLSM images. cCUR/HPβCD-IC-sPLA-NF released CUR slowly but much more in total than PLA-CUR-NF at pH 1 and pH 7.4 due to the restriction of CUR in the core of nanofibers and solubility improvement shown in phase solubility diagram, respectively. Improved antioxidant activity of cCUR/HPβCD-IC-sPLA-NF in methanol:water (1:1) is related with the solubility enhancement achieved in water based system. The slow reaction of cCUR/HPβCD-IC-sPLA-NF in methanol is associated with the shell inhibiting the quick release of CUR. On the other hand, cCUR/HPβCD-IC-sPLA-NF exhibited slightly higher rate of antioxidant activity than PLA-CUR-NF in methanol:water (1:1) owing to the enhanced solubility. To conclude, slow release of CUR was achieved by core-shell nanofiber structure and inclusion complexation of CUR with HPβCD provides high solubility. Briefly, electrospinning of core-shell nanofibers with CD-IC core could offer slow release of drugs as well as solubility enhancement for hydrophobic drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Waste fatty acid addition to black liquor to decrease tall oil soap solubility and increase skimming efficiency in kraft mills pulping mountain pine beetle-infested wood

    Energy Technology Data Exchange (ETDEWEB)

    Uloth, V.; Guy, E. [FPInnovations, Prince George, BC (Canada). PAPRICAN Div.; Shewchuk, D. [Cariboo Pulp and Paper, Quesnel, BC (Canada); Van Heek, R. [Aker Kvaerner, Vancouver, BC (Canada)

    2009-07-01

    This paper presented the results of tests conducted to determine if the addition of waste fatty acids from vegetable oil processing might decrease tall oil soap solubility in pine-beetle impacted wood from British Columbia (BC). The soap recovery and tall oil production at BC mills has fallen by 30 to 40 percent in recent years due to the pulping of high proportions of grey-stage beetle-impacted wood. Full-scale mill tests were conducted over a 4-day period. The study showed that the addition of tall oil fatty acids or waste fatty acids from vegetable oil processing could decrease tall oil soap solubility and increase the soup skimming efficiency in mills pulping a large percentage of grey stage beetle-infested wood. The addition of fatty acids increased tall oil soap skimming efficiency from 50.2 percent in the baseline tests to 71.8 percent based on the total soap available, and from 76.7 percent in the baseline tests to 87.5 percent based on insoluble soap only. The economic analyses indicated that waste fatty acid addition could be economical when natural gas and oil prices are high. 4 tabs., 9 figs.

  8. Long-term observation of water-soluble chemical components and acid-digested metals in the total suspended particles collected at Okinawa, Japan

    Science.gov (United States)

    Handa, D.; Okada, K.; Kuroki, Y.; Nakama, Y.; Nakajima, H.; Somada, Y.; Ijyu, M.; Azechi, S.; Oshiro, Y.; Nakaema, F.; Miyagi, Y.; Arakaki, T.; Tanahara, A.

    2011-12-01

    The economic growth and population increase in recent Asia have been increasing air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location is ideal in observing East Asia's air quality because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background clean air and can be compared with continental air masses which have been affected by anthropogenic activities. We collected total suspended particles (TSP) on quartz filters by using a high volume air sampler at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS), Okinawa, Japan during August 2005 and August 2010. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations, water-soluble organic carbon (WSOC) and acid-digested metals in TSP samples using ion chromatography, atomic absorption spectrometry, total organic carbon analyzer and Inductively Coupled Plasma Mass spectrometry (ICP-MS), respectively. Seasonal variation of water-soluble chemical components and acid-digested metals showed that the concentrations were the lowest in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian continent, the concentrations of water-soluble chemical components and acid-digested metals were much higher compared to the other directions, suggesting long-range transport of air pollutants from Asian continent. Also, when the air mass came from Asian continent (75-100% dominant), the mean concentrations of non-sea salt sulfate and nitrate increased ca. 1.8 times and ca. 3.7 times, respectively between 2005 and 2010, and the ratio of nitrate to

  9. Study of the solubility of yttrium, praseodymium, neodymium, and gadolinium sulfates in the presence of sodium and potassium in sulfuric-phosphoric acid solutions at 20 deg C

    International Nuclear Information System (INIS)

    Lokshin, Eh.P.; Tareeva, O.A.; Kashulina, T.G.

    2007-01-01

    The solubility of yttrium, praseodymium, neodymium, and gadolinium sulfates in the presence of sodium and potassium ions and the composition of solid phases were studied at 20 deg C in relation to the concentration of acids in sulfuric acid, phosphoric acid, and sulfuric-phosphoric acid solutions containing up to 36 wt % H 2 SO 4 and 33.12 g 1 -1 H 3 PO 4 . The formation of double sulfates of praseodymium and neodymium with sodium and potassium ions, as well as of gadolinium sulfate with sodium ions of the composition 1 : 1 was revealed. In water at 20 deg C, the solubility products of PrNa(SO 4 ) 2 ·H 2 O, NdNa(SO 4 ) 2 ·H 2 O, GdNa(SO 4 ) 2 ·H 2 O, PrK(SO 4 ) 2 ·H 2 O, and NdK(SO 4 ) 2 ·H 2 O are found to be 7.28x10 -8 , 7.84x10 -8 , 3.09x10 -6 , 3.02x10 -6 , and 1.70x10 -6 , respectively [ru

  10. Electrochemical quantification of some water soluble vitamins in commercial multi-vitamin using poly-amino acid caped by graphene quantum dots nanocomposite as dual signal amplification elements.

    Science.gov (United States)

    Shadjou, Nasrin; Hasanzadeh, Mohammad; Omari, Ali

    2017-12-15

    Rapid analyses of some water soluble vitamins (Vitamin B2, B9, and C) in commercial multi vitamins could be routinely performed in analytical laboratories. This study reports on the electropolymerization of a low toxic and biocompatible polymer "poly aspartic acid-graphene quantum dots" as a novel strategy for surface modification of glassy carbon electrode and preparation a new interface for measurement of selected vitamins in commercial multi vitamins. Electrochemical deposition, as a well-controlled synthesis procedure, has been used for subsequently layer-by-layer preparation of graphene quantum dots nanostructures on a poly aspartic acid using cyclic voltammetry techniques in the regime of -1.5 to 2 V. The field emission scanning electron microscopy indicated immobilization of graphene quantum dots onto poly aspartic acid film. The modified electrode possessed as an effective electroactivity for detection of water soluble vitamins by using cyclic voltammetry, chronoamperometry and differential pulse voltammetry. Enhancement of peak currents is ascribed to the fast heterogeneous electron transfer kinetics that arise from the synergistic coupling between the excellent properties of poly aspartic acid as semiconducting polymer, graphene quantum dots as high density of edge plane sites and chemical modification. Under the optimized analysis conditions, the prepared sensor for detection of VB2, VB9, and VC showed a low limit of quantification 0.22, 0.1, 0.1 μM, respectively. Copyright © 2017. Published by Elsevier Inc.

  11. Using urinary solubility data to estimate the level of safety concern of low levels of melamine (MEL) and cyanuric acid (CYA) present simultaneously in infant formulas.

    Science.gov (United States)

    Dominguez-Estevez, Manuel; Constable, Anne; Mazzatorta, Paolo; Renwick, Andrew G; Schilter, Benoit

    2010-01-01

    Melamine (MEL) and cyanuric acid (CYA) may occur simultaneously in milk products. There is no health based guidance value for the mixture of MEL+CYA. Limited toxicological data indicate that MEL+CYA toxicity occurs at levels lower than the toxic doses of the single compounds. The key adverse effect of MEL+CYA is the formation of crystals in the urinary tract, which is dependent on the solubility of the MEL+CYA complex. Urinary concentrations resulting from oral doses of MEL+CYA and MEL alone have been calculated from published data from animal studies. A human exposure scenario assuming consumption of infant formula contaminated at a level of 1 ppm of MEL and CYA each (2 ppm of MEL+CYA) was also analyzed. Margins of more than two orders or magnitude were observed between estimated urine concentrations known to be without detectable effects in rats and calculated human urine concentrations. Because the hazard is related to the physico-chemical characteristics of the mixture, there would be a negligible concern associated with crystal formation if the urinary concentration of the complex is within the solubility range. The solubility of MEL+CYA was higher in urine than in water. A strong pH-dependency was observed with the lowest solubility found at pH 5-5.5. The calculated human urinary concentration was about 30 times less than the solubility limit for MEL+CYA in adult human urine. Altogether, these data provide preliminary evidence suggesting that the presence of 1 ppm of MEL and CYA each in infant formula is unlikely to be of significant health concern. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Thermodynamic functions for solubility of 3-nitro-o-toluic acid in nine organic solvents from T = (283.15 to 318.15) K and apparent thermodynamic properties of solutions

    International Nuclear Information System (INIS)

    Li, Xinbao; Wang, Mingju; Du, Cunbin; Cong, Yang; Zhao, Hongkun

    2017-01-01

    Highlights: • Solubilities of 3-nitro-o-toluic acid in nine organic solvents were determined. • The solubilities were correlated by using four thermodynamic models. • The mixing properties of solution were computed based on Wilson model. - Abstract: Separation of 3-nitro-o-toluic acid from its isomeric mixtures has essential significance in industry. In this work, by using isothermal saturation method, the solid-liquid equilibrium for 3-nitro-o-toluic acid in nine organic solvents (acetonitrile, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, acetone, 1,4-dioxane and 2-butanone) were obtained experimentally within a temperature range from (283.15 to 318.15) K under atmosphere pressure of 101.2 kPa, and the solubility values of 3-nitro-o-toluic acid in these solvents were determined by a high-performance liquid chromatography. Within the studied temperature range, the mole fraction solubility of 3-nitro-o-toluic acid in selected organic solvents increased with increasing temperature. Except for ethyl acetate, the descending order of the mole fraction solubility values were as follow: 1,4-dioxane > acetone > 2-butanone > methanol > ethanol > isopropanol > n-propanol > acetonitrile. The solubility values determined for 3-nitro-o-toluic acid in the selected solvents were correlated and back calculated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of RAD and RMSD obtained with the four models were 0.67% and 4.02 × 10 −4 , respectively. In general, the four thermodynamic models were all acceptable for describing the solubility behaviour of 3-nitro-o-toluic acid in these solvents. In addition, the apparent mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were calculated. The acquired solubility data and thermodynamic studies would be very important in optimizing the separation process of 3-nitro-o-toluic acid from

  13. Structural Characterization of Febuxostat/l-Pyroglutamic Acid Cocrystal Using Solid-State 13C-NMR and Investigational Study of Its Water Solubility

    Directory of Open Access Journals (Sweden)

    Ji-Hun An

    2017-12-01

    Full Text Available Febuxostat (FB is a poorly water-soluble drug that belongs to BCS class II. The drug is employed for the treatment of inflammatory disease arthritis urica (gout, and the free base, FB form-A, is most preferred for drug formulation. In order to achieve a goal of improving the water solubility of FB form-A, this study was carried out using the cocrystallization technique called the liquid-assisted grinding method to produce FB cocrystals. Here, five amino acids containing amine (NH, oxygen (O, and hydroxyl (OH functional groups, and possessing difference of pKa less than 3 with FB, were selected as coformers. Then, solvents including methanol, ethanol, isopropyl alcohol, n-hexane, dichloromethane, and acetone were used for the cocrystal screening. As a result, a cocrystal was obtained when acetone and l-pyroglutamic acid (PG of 0.5 eq. were employed as solvent and coformer, respectively. The ratio of 2:1, which is the ratio of FB to PG within FB-PG cocrystal, was predicted by means of solid-state CP/MAS 13C-NMR, solution-state NMR (1H, 13C, and 2D and FT-IR. Moreover, Powder X-ray Diffraction (PXRD, Differential Scanning Calorimetry (DSC, and Thermogravimetric Analysis (TGA were used to investigate the characteristics of FB-PG cocrystal. In addition, comparative solubility tests between FB-PG cocrystal and FB form-A were conducted in deionized water and under simulated gastrointestinal pH (1.2, 4, and 6.8 conditions. The result revealed that FB-PG cocrystal has a solubility of four-fold higher than FB form-A in deionized water and two-fold and five-fold greater than FB form-A at simulated gastrointestinal pH 1.2 and pH 4, respectively. Besides, solubilities of FB-PG cocrystal and FB form-A at pH 6.8 were similar to the results measured in deionized water. Therefore, it is postulated that FB-PG cocrystal has a potential overcoming the limitations related to the low aqueous solubility of FB form-A. Accordingly, FB-PG cocrystal is suggested as an

  14. Electrospinning of calcium phosphate-poly(D,L-lactic acid nanofibers for sustained release of water-soluble drug and fast mineralization

    Directory of Open Access Journals (Sweden)

    Fu QW

    2016-10-01

    Full Text Available Qi-Wei Fu,1,* Yun-Peng Zi,1,* Wei Xu,1 Rong Zhou,1 Zhu-Yun Cai,1 Wei-Jie Zheng,1 Feng Chen,2 Qi-Rong Qian1 1Department of Orthopedics, Changzheng Hospital, Second Military Medical University, 2State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Calcium phosphate-based biomaterials have been well studied in biomedical fields due to their outstanding chemical and biological properties which are similar to the inorganic constituents in bone tissue. In this study, amorphous calcium phosphate (ACP nanoparticles were prepared by a precipitation method, and used for preparation of ACP-poly(D,L-lactic acid (ACP-PLA nanofibers and water-soluble drug-containing ACP-PLA nanofibers by electrospinning. Promoting the encapsulation efficiency of water-soluble drugs in electrospun hydrophobic polymer nanofibers is a common problem due to the incompatibility between the water-soluble drug molecules and hydrophobic polymers solution. Herein, we used a native biomolecule of lecithin as a biocompatible surfactant to overcome this problem, and successfully prepared water-soluble drug-containing ACP-PLA nanofibers. The lecithin and ACP nanoparticles played important roles in stabilizing water-soluble drug in the electrospinning composite solution. The electrospun drug-containing ACP-PLA nanofibers exhibited fast mineralization in simulated body fluid. The ACP nanoparticles played the key role of seeds in the process of mineralization. Furthermore, the drug-containing ACP-PLA nanofibers exhibited sustained drug release which simultaneously occurred with the in situ mineralization in simulated body fluid. The osteoblast-like (MG63 cells with spreading filopodia were well observed on the as-prepared nanofibrous mats after culturing for 24 hours, indicating a high cytocompatibility. Due

  15. Influence of water solubility, side chain degradability and side chain configuration on the degradation of phthalic acid esters under methanogenic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Alnervik, M.

    1996-12-31

    Water solubility and degradability of side chains estrifying phthalic acid are factors possible to influence the degradation of phthalic acid esters (PAEs). To investigate the importance of these factors degradation of butyl 2-ethylhexyl phthalate (BEHP), bis(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), dihexyl phthalate (DHP), dioctyl phthalate (DOP) and didecyl phthalate (DDP) were examined under methanogenic conditions as well as was the degradability of the alcohols estrifying these PAEs. We also investigated if the degradation of resistant PAEs could be stimulated by the addition of a degradable PAE. Synthesis of degradation intermediates and two methods for PAE analyses are presented. The investigation showed that all alcohols were degraded to methane and carbon dioxide and that the degradation of PAE occurred in incubations amended with BBP, BEHP, DHP and DBP, whilst DEHP, DOP and DDP were unaffected throughout the experimental period. BBP added to incubations with DEHP, could not stimulate DEHP degradation. In conclusion, the degradability of alcohols estrifying phthalic acid in this study does not affect the anaerobic degradability of PAEs. Water solubility of a PAE can not be rejected as a factor limiting phthalate degradation under methanogenic conditions. Anaerobic degradation of persistent PAEs can not be stimulated by mixing it with a degradable phthalate. 23 refs, 11 figs, 2 tabs

  16. The Changes in Color, Soluble Sugars, Organic Acids, Anthocyanins and Aroma Components in “Starkrimson” during the Ripening Period in China

    Directory of Open Access Journals (Sweden)

    Yulian Liu

    2016-06-01

    Full Text Available “Starkrimson” is a traditional apple cultivar that was developed a long time ago and was widely cultivated in the arid region of the northern Wei River of China. However, little information regarding the quality characteristics of “Starkrimson” fruit has been reported in this area. To elucidate these characteristics, the color, soluble sugars, organic acids, anthocyanins and aroma components were measured during the ripening period through the use of high performance liquid chromatography (HPLC and gas chromatography-mass spectrometry (GC-MS. The results indicated that the changes in anthocyanin contents took place later than the changes in the Commission International Eclairage (CIE parameters. Meanwhile, cyanidin 3-galactoside (cy3-gal, fructose, sucrose, glucose and malic acid were the primary organic compounds, and 1-butanol-2-methyl-acetate, 2-hexenal and 1-hexanol were the most abundant aroma components in the skin. Furthermore, rapidly changing soluble sugars and organic acid synchronization took place in the early ripening period, while rapidly changing aroma components occurred later, on the basis of fresh weight. This result suggested that the production of aroma components might be a useful index of apple maturity.

  17. Effect of phospholipid-based formulations of Boswellia serrata extract on the solubility, permeability, and absorption of the individual boswellic acid constituents present.

    Science.gov (United States)

    Hüsch, Jan; Gerbeth, Kathleen; Fricker, Gert; Setzer, Constanze; Zirkel, Jürgen; Rebmann, Herbert; Schubert-Zsilavecz, Manfred; Abdel-Tawab, Mona

    2012-10-26

    Boswellia serrata gum resin extracts are used widely for the treatment of inflammatory diseases. However, very low concentrations in the plasma and brain were observed for the boswellic acids (1-6, the active constituents of B. serrata). The present study investigated the effect of phospholipids alone and in combination with common co-surfactants (e.g., Tween 80, vitamin E-TPGS, pluronic f127) on the solubility of 1-6 in physiologically relevant media and on the permeability in the Caco-2 cell model. Because of the high lipophilicity of 1-6, the permeability experiments were adapted to physiological conditions using modified fasted state simulated intestinal fluid as apical (donor) medium and 4% bovine serum albumin in the basolateral (receiver) compartment. A formulation composed of extract/phospholipid/pluronic f127 (1:1:1 w/w/w) increased the solubility of 1-6 up to 54 times compared with the nonformulated extract and exhibited the highest mass net flux in the permeability tests. The oral administration of this formulation to rats (240 mg/kg) resulted in 26 and 14 times higher plasma levels for 11-keto-β-boswellic acid (1) and acetyl-11-keto-β-boswellic acid (2), respectively. In the brain, five times higher levels for 2 compared to the nonformulated extract were determined 8 h after oral administration.

  18. Plutonium solubilities

    International Nuclear Information System (INIS)

    Puigdomnech, I.; Bruno, J.

    1991-02-01

    Thermochemical data has been selected for plutonium oxide, hydroxide, carbonate and phosphate equilibria. Equilibrium constants have been evaluated in the temperature range 0 to 300 degrees C at a pressure of 1 bar to T≤100 degrees C and at the steam saturated pressure at higher temperatures. Measured solubilities of plutonium that are reported in the literature for laboratory experiments have been collected. Solubility data on oxides, hydroxides, carbonates and phosphates have been selected. No solubility data were found at temperatures higher than 60 degrees C. The literature solubility data have been compared with plutonium solubilities calculated with the EQ3/6 geochemical modelling programs, using the selected thermodynamic data for plutonium. (authors)

  19. Prediction of Starch, Soluble Sugars and Amino Acids in Potatoes (Solanum tuberosum L.) Using Hyperspectral Imaging, Dielectric and LF-NMR Methodologies

    DEFF Research Database (Denmark)

    Kjær, Anders; Nielsen, Glenn; Stærke, Søren

    2016-01-01

    Handling and processing of potatoes is performed in increasingly large and more automated facilities, and the industry calls for more automated machinery for quality assessment and sorting by concentration of starch, soluble sugars, protein, amino acids etc. of the potato tubers. The present study...... cultivars were simultaneously sampled for analyses of content and scanned by the five different scanning methods. The resulting multivariate dataset was used to estimate the prediction ability of the individual scanning methods on starch-related parameters, selected simple sugars, selected amino acids......, conductivity of pressed cell sap and cell sizes. Results showed that most types of spectral analyses had relatively high potential for predicting the starch-related parameters and medium potential for predicting the concentration of the reducing sugars fructose and glucose. Most methods showed medium potential...

  20. N-3 Polyunsaturated Fatty Acids Decrease the Protein Expression of Soluble Epoxide Hydrolase via Oxidative Stress-Induced P38 Kinase in Rat Endothelial Cells.

    Science.gov (United States)

    Okada, Takashi; Morino, Katsutaro; Nakagawa, Fumiyuki; Tawa, Masashi; Kondo, Keiko; Sekine, Osamu; Imamura, Takeshi; Okamura, Tomio; Ugi, Satoshi; Maegawa, Hiroshi

    2017-06-24

    N -3 polyunsaturated fatty acids (PUFAs) improve endothelial function. The arachidonic acid-derived metabolites (epoxyeicosatrienoic acids (EETs)) are part of the endothelial hyperpolarization factor and are vasodilators independent of nitric oxide. However, little is known regarding the regulation of EET concentration by docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in blood vessels. Sprague-Dawley rats were fed either a control or fish oil diet for 3 weeks. Compared with the control, the fish oil diet improved acetylcholine-induced vasodilation and reduced the protein expression of soluble epoxide hydrolase (sEH), a key EET metabolic enzyme, in aortic strips. Both DHA and EPA suppressed sEH protein expression in rat aorta endothelial cells (RAECs). Furthermore, the concentration of 4-hydroxy hexenal (4-HHE), a lipid peroxidation product of n -3 PUFAs, increased in n -3 PUFA-treated RAECs. In addition, 4-HHE treatment suppressed sEH expression in RAECs, suggesting that 4-HHE (derived from n -3 PUFAs) is involved in this phenomenon. The suppression of sEH was attenuated by the p38 kinase inhibitor (SB203580) and by treatment with the antioxidant N-acetyl-L-cysteine. In conclusion, sEH expression decreased after n -3 PUFAs treatment, potentially through oxidative stress and p38 kinase. Mild oxidative stress induced by n -3 PUFAs may contribute to their cardio-protective effect.

  1. Nitrogen-corrected True Metabolizable Energy and Amino Acid Digestibility of Chinese Corn Distillers Dried Grains with Solubles in Adult Cecectomized Roosters

    Directory of Open Access Journals (Sweden)

    F. Li

    2013-06-01

    Full Text Available This study was conducted to evaluate chemical composition, nitrogen-corrected true metabolizable energy (TMEn and true amino acids digestibility of corn distillers dried grains with solubles (DDGS produced in China. Twenty five sources of corn DDGS was collected from 8 provinces of China. A precision-fed rooster assay was used to determine TMEn and amino acids digestibility with 35 adult cecectomized roosters, in which each DDGS sample was tube fed (30 g. The average content of ash, crude protein, total amino acid, ether extract, crude fiber and neutral detergent fiber were 4.81, 27.91, 22.51, 15.22, 6.35 and 37.58%, respectively. TMEn of DDGS ranged from 1,779 to 3,071 kcal/kg and averaged 2,517 kcal/kg. Coefficient of variation for non-amino acid crude protein, ether extract, crude fiber and TMEn were 55.0, 15.7, 15.9 and 17.1%, respectively. The average true amino acid digestibility was 77.32%. Stepwise regression analysis obtained the following equation: TMEn, kcal/kg = −2,995.6+0.88×gross energy+49.63×a* (BIC = 248.8; RMSE = 190.8; p0.05. These results suggest that corn DDGS produced in China has a large variation in chemical composition, and gross energy and a* value can be used to generate TMEn predict equation.

  2. Light exposure during storage preserving soluble sugar and l-ascorbic acid content of minimally processed romaine lettuce (Lactuca sativa L.var. longifolia).

    Science.gov (United States)

    Zhan, Lijuan; Hu, Jinqiang; Ai, Zhilu; Pang, Lingyun; Li, Yu; Zhu, Meiyun

    2013-01-01

    Minimally processed romaine lettuce (MPRL) leaves were stored in light condition (2500lux) or darkness at 4°C for 7d. Light exposure significantly delayed the degradation of chlorophyll and decrease of glucose, reducing sugar, and sucrose content, and thus preserved more total soluble solid (TSS) content at the end of storage in comparison with darkness. While, it did not influenced starch content that progressively decreased over time. The l-ascorbic acid (AA) accumulated in light-stored leaves, but deteriorated in dark-stored leaves during storage. The dehydroascorbic acid (DHA) increased in all leaves stored in both light and dark condition, of which light condition resulted in less DHA than darkness. In addition, the fresh weight loss and dry matter significantly increased and these increases were accelerated by light exposure. Conclusively, light exposure in applied intensity effectively alleviated MPRL quality deterioration by delaying the decreases of pigments, soluble sugar, TSS content and accumulating AA. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Synthesis and electrochemical probing of water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes

    International Nuclear Information System (INIS)

    Du Feipeng; Yang Yingkui; Xie Xiaolin; Wu Kangbing; Gan Tian; Liu Lang

    2008-01-01

    Water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes (MWNT-g-P(SSS-co-AA)) with core-shell nanostructure were successfully synthesized by in situ free radical copolymerization of sodium 4-strenesulfonate (SSS) and acrylic acid (AA) in the presence of MWNTs terminated with vinyl groups; their structure was characterized by FTIR, 1 H NMR, Raman, TGA and TEM. The results showed that the thickness and content of the copolymer layer grafted onto the MWNT surface are about 7-12 nm and 82.3%, respectively. The P(SSS-co-AA) covalently grafted on MWNTs provides MWNT-g-P(SSS-co-AA) with good hydrophilicity and solubility in water. Then a novel MWNT-g-P(SSS-co-AA)-modified glassy carbon electrode was fabricated by coating; its electrochemical properties were evaluated by electrochemical probe of K 3 [Fe(CN) 6 ], and its catalytic behaviors to the electrochemical oxidation processes of dopamine (DA) and serotonin (5-HT) were investigated. Since the MWNT-g-P(SSS-co-AA)-modified electrode possesses strong electron transfer capability, high electrochemical activity and catalytic ability, it can be used in sensitive, selective, rapid and simultaneous monitoring of biomolecules

  4. delta 6 Hexadecenoic acid is synthesized by the activity of a soluble delta 6 palmitoyl-acyl carrier protein desaturase in Thunbergia alata endosperm.

    Science.gov (United States)

    Cahoon, E B; Cranmer, A M; Shanklin, J; Ohlrogge, J B

    1994-11-04

    delta 6 Hexadecenoic acid (16:1 delta 6) composes more than 80% of the seed oil of Thunbergia alata. Studies were conducted to determine the biosynthetic origin of the double bond of this unusual fatty acid. Assays of fractions of developing T. alata seed endosperm with [1-14C]palmitoyl (16:0)-acyl carrier protein (ACP) revealed the presence of a soluble delta 6 desaturase activity. This activity was greatest when 16:0-ACP was provided as a substrate, whereas no desaturation of the coenzyme A ester of this fatty acid was detected. In addition, delta 6 16:0-ACP desaturase activity in T. alata endosperm extracts was dependent on the presence of ferredoxin and molecular oxygen and was stimulated by catalase. To further characterize this enzyme, a cDNA encoding a diverged acyl-ACP desaturase was isolated from a T. alata endosperm cDNA library using polymerase chain reaction with degenerate oligonucleotides corresponding to conserved amino acid sequences in delta 9 stearoyl (18:0)- and delta 4 16:0-ACP desaturases. The primary structure of the mature peptide encoded by this cDNA shares 66% identity with the mature castor delta 9 18:0-ACP desaturase and 57% identity with the mature coriander delta 4 16:0-ACP desaturase. Extracts of Escherichia coli that express the T. alata cDNA catalyzed the delta 6 desaturation of 16:0-ACP. These results demonstrate that 16:1 delta 6 in T. alata endosperm is formed by the activity of a soluble delta 6 16:0-ACP desaturase that is structurally related to the delta 9 18:0- and delta 4 16:0-ACP desaturases. Implications of this work to an understanding of active site structures of acyl-ACP desaturases are discussed.

  5. Solubility and acid-base properties of concentrated phytate in self-medium and in NaCl{sub aq} at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Cigala, Rosalia Maria; Crea, Francesco; Lando, Gabriele; Milea, Demetrio [Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Universita di Messina, Via Ferdinando Stagno d' Alcontres, 31, I-98166 Messina (Vill. S. Agata) (Italy); Sammartano, Silvio, E-mail: ssammartano@unime.i [Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Universita di Messina, Via Ferdinando Stagno d' Alcontres, 31, I-98166 Messina (Vill. S. Agata) (Italy)

    2010-11-15

    The acid-base properties of concentrated phytic acid were studied in self-medium and in NaCl{sub aq} (0.5 {<=} I/mol . L{sup -1} {<=} 4.0) by ISE-H{sup +} potentiometry and by direct calorimetry, at T = 298.15 K. At ligand concentrations c{sub (Phy)} > 0.012 mol . L{sup -1}, the formation of several binuclear H{sub i}(Phy){sub 2} (2 {<=} i {<=} 10) species was observed, in addition to the mononuclear H{sub i}Phy (1 {<=} i {<=} 7) ones. The solubility of phytate dodecasodium salt was studied in pure water and in NaCl{sub aq} at different ionic strengths; the total solubility in pure water is S{sub 0}{sup T}=(0.300{+-}0.004)mol.L{sup -1} and it decreases markedly with increasing ionic strength; for example the total solubility of Na{sub 12}Phy at I = 3.0 mol . L{sup -1} is 0.008 mol . L{sup -1}. By the dependence on ionic strength (salt concentration) of the solubility, it was possible to calculate the activity coefficients of phytate as a function of medium concentration. Direct calorimetric titrations were also carried out on Na{sub 12}Phy aqueous solutions at different phytate concentrations (0.025 {<=} c{sub (Phy)}/mol . L{sup -1} {<=} 0.100) and without addition of supporting electrolyte, in order to calculate the enthalpy changes for the protonation equilibria in self-medium of the binuclear H{sub i}(Phy){sub 2} species, at T = 298.15 K. It was observed that the {Delta}H/kJ . mol{sup -1} of the binuclear species are, within the experimental error, independent of the ionic strength; for example for the H{sub 2}(Phy){sub 2} species we obtained: {Delta}H{sub 22} = (-23.6 {+-} 0.6) kJ . mol{sup -1}, and (-23.7 {+-} 0.2) kJ . mol{sup -1} at I = 0.50 and 2.0 mol . L{sup -1}, respectively.

  6. Production of furfural from xylose, water-insoluble hemicelluloses and water-soluble fraction of corncob via a tin-loaded montmorillonite solid acid catalyst.

    Science.gov (United States)

    Li, Huiling; Ren, Junli; Zhong, Linjie; Sun, Runcang; Liang, Lei

    2015-01-01

    The conversion of xylose, water-insoluble hemicelluloses (WIH) and water-soluble fraction (WSF) of corncob to furfural was performed using montmorillonite with tin ions (Sn-MMT) containing double acid sites as a solid acid catalyst. The co-existence of Lewis acids and Brønsted acids in Sn-MMT was shown to improve the furfural yield and selectivity. 76.79% furfural yield and 82.45% furfural selectivity were obtained from xylose using Sn-MMT as a catalyst in a biphasic system with 2-s-butylphenol (SBP) as the organic extracting layer and dimethyl sulfoxide (DMSO) as the co-solvent in contact with an aqueous phase saturated with NaCl (SBP/NaCl-DMSO) at 180°C for 30min. Furthermore, Sn-MMT also demonstrated the excellent catalytic performance in the conversion of pentose-rich materials of corncob and 39.56% and 54.15% furfural yields can be directly obtained from WIH and WSF in the SBP/NaCl-DMSO system, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Preparation of hydrolytic liquid from dried distiller's grains with solubles and fumaric acid fermentation by Rhizopus arrhizus RH 7-13.

    Science.gov (United States)

    Liu, Huan; Yue, Xuemin; Jin, Yuhan; Wang, Meng; Deng, Li; Wang, Fang; Tan, Tianwei

    2017-10-01

    Fumaric acid production from lignocellulosic materials is an alternative chemicals production system. This work investigated the suitable conditions for hydrolysis of dried distiller's grains with solubles (DDGS). The hydrolytic liquid was subsequently used for the production of fumaric acid. After optimizing the hydrolysis conditions, the most suitable concentration of H 2 SO 4 (2%), hydrolysis temperature (120 °C), hydrolysis time (100min) and solid/liquid ratio (1:10) were obtained. The yield of monosaccharides reached 258 mg/g DDGS and 15.88 g/L glucose, 7.53 g/L xylose and 2.35 g/L arabinose were obtained in unprocessed hydrolytic liquid. The furfural inhibitor in the hydrolytic liquid was also detected and the yield of it was reducing progressively in the pretreatment process. The ferment ability of the hydrolytic liquid from DDGS was tested through the process of fumaric acid production by Rhizopus arrhizus RH 7-13. The unprocessed hydrolytic liquid was not appropriate for the fermentation process. The yield of fumaric acid from the concentrated processed hydrolytic liquid reached 18.93 g/L, which was close to the yield of fermenting 80 g/L glucose. This result indicated that the commonly used carbon resource glucose could to some extent be replaced by processed hydrolytic liquid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Nanoparticles with high payloads of pipemidic acid, a poorly soluble crystalline drug: drug-initiated polymerization and self-assembly approach

    Directory of Open Access Journals (Sweden)

    Elisabetta Pancani

    2018-05-01

    Full Text Available Nowadays, biodegradable polymers such as poly(lactic acid (PLA, poly(D,L-lactic-co-glycolic acid (PLGA and poly(ε-caprolactone (PCL remain the most common biomaterials to produce drug-loaded nanoparticles (NPs. Pipemidic acid (PIP is a poorly soluble antibiotic with a strong tendency to crystallize. PIP incorporation in PLA/PLGA NPs was challenging because of PIP crystals formation and burst release. As PIP had a poor affinity for the NPs, an alternative approach to encapsulation was used, consisting in coupling PIP to PCL. Thus, a PCL–PIP conjugate was successfully synthesized by an original drug-initiated polymerization in a single step without the need of catalyst. PCL–PIP was characterized by NMR, IR, SEC and mass spectrometry. PCL–PIP was used to prepare self-assembled NPs with PIP contents as high as 27% (w/w. The NPs were characterized by microscopy, DLS, NTA and TRPS. This study paves the way towards the production of NPs with high antibiotic payloads by drug-initiated polymerization. Further studies will deal with the synthesis of novel polymer–PIP conjugates with ester bonds between the drug and PCL. PIP can be considered as a model drug and the strategy developed here could be extended to other challenging antibiotics or anticancer drugs and employed to efficiently incorporate them in NPs. KEY WORDS: Pipemidic acid, Nanoparticle, Antibiotic, Nanoprecipitation, Crystalline drug, Drug-initiated   polymerization

  9. Pretreatment of Dried Distiller Grains with Solubles by Soaking in Aqueous Ammonia and Subsequent Enzymatic/Dilute Acid Hydrolysis to Produce Fermentable Sugars.

    Science.gov (United States)

    Nghiem, Nhuan P; Montanti, Justin; Kim, Tae Hyun

    2016-05-01

    Dried distillers grains with solubles (DDGS), a co-product of corn ethanol production in the dry-grind process, was pretreated by soaking in aqueous ammonia (SAA) using a 15 % w/w NH4OH solution at a solid/liquid ratio of 1:10. The effect of pretreatment on subsequent enzymatic hydrolysis was studied at two temperatures (40 and 60 °C) and four reaction times (6, 12, 24, and 48 h). Highest glucose yield of 91 % theoretical was obtained for the DDGS pretreated at 60 °C and 24 h. The solubilized hemicellulose in the liquid fraction was further hydrolyzed with dilute H2SO4 to generate fermentable monomeric sugars. The conditions of acid hydrolysis included 1 and 4 wt% acid, 60 and 120 °C, and 0.5 and 1 h. Highest yields of xylose and arabinose were obtained at 4 wt% acid, 120 °C, and 1 h. The fermentability of the hydrolysate obtained by enzymatic hydrolysis of the SAA-pretreated DDGS was demonstrated in ethanol fermentation by Saccharomyces cerevisiae. The fermentability of the hydrolysate obtained by consecutive enzymatic and dilute acid hydrolysis was demonstrated using a succinic acid-producing microorganism, strain Escherichia coli AFP184. Under the fermentation conditions, complete utilization of glucose and arabinose was observed, whereas only 47 % of xylose was used. The succinic acid yield was 0.60 g/g total sugar consumed.

  10. [Effects of excess folic acid on growth and metabolism of water-soluble vitamins in weaning rats].

    Science.gov (United States)

    Fukuwatari, Tsutomu; Shibata, Katsumi

    2008-02-01

    In order to determine the tolerable upper intake level of folic acid in humans, we investigated the effects of excessive folic acid administration on the body weight gain, food intake, tissue weight, and metabolism of B-group vitamins in weaning rats. The rats were freely fed ordinary diet containing 0.0002% folic acid (control diet) or the same diet with 0.01%, 0.1%, or 1.0% folic acid for 29 days. The body weight gains and food intakes did not differ among the four groups. Diarrhea was not seen even in the 1.0% group. Excess folic acid did not affect the tissue weights of the brain, heart, liver, kidney, spleen, lung, or testis, or urinary excretion of other B-group vitamins. These results clearly showed that feeding a diet containing up to 1.0% folic acid did not affect the food intake, body weight gain, tissue weight, or urinary excretion of B-group vitamins in weaning rats.

  11. Evaluation of soluble fraction and enzymatic residual fraction of dilute dry acid, ethylenediamine, and steam explosion pretreated corn stover on the enzymatic hydrolysis of cellulose.

    Science.gov (United States)

    Qin, Lei; Liu, Li; Li, Wen-Chao; Zhu, Jia-Qing; Li, Bing-Zhi; Yuan, Ying-Jin

    2016-06-01

    This study is aimed to examine the inhibition of soluble fraction (SF) and enzymatic residual fraction (ERF) in dry dilute acid (DDA), ethylenediamine (EDA) and steam explosion (SE) pretreated corn stover (CS) on the enzymatic digestibility of cellulose. SF of DDA, EDA and SE pretreated CS has high xylose, soluble lignin and xylo-oligomer content, respectively. SF of EDA pretreated CS leads to the highest inhibition, followed by SE and DDA pretreated CS. Inhibition of ERF of DDA and SE pretreated CS is higher than that of EDA pretreated CS. The inhibition degree (A0/A) of SF is 1.76 and 1.21 times to that of ERF for EDA and SE pretreated CS, respectively. The inhibition degree of ERF is 1.05 times to that of SF in DDA pretreated CS. The quantitative analysis shows that SF of EDA pretreated CS, SF and ERF of SE pretreated CS cause significant inhibition during enzymatic hydrolysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Initial solubility & density evaluation of Non-Aqueous system of amino acid salts for CO2 capture: potassium prolinate blended with ethanol and ethylene glycol

    Science.gov (United States)

    Murshid, Ghulam; Garg, Sahil

    2018-05-01

    Amine scrubbing is the state of the art technology for CO2 capture, and solvent selection can significantly reduce the capital and energy cost of the process. Higher energy requirement for aqueous amine based CO2 removal process is still a most important downside preventive its industrial deployment. Therefore, in this study, novel non-aqueous based amino acid salt system consisting of potassium prolinate, ethanol and ethylene glycol has been studied. This work presents initial CO2 solubility study and important physical properties i.e. density of the studied solvent system. Previous work showed that non-aqueous system of potassium prolinate and ethanol has good absorption rates and requires lower energy for solvent regeneration. However, during regeneration, solvent loss issues were found due to lower boiling point of the ethanol. Therefore, ethylene glycol was added into current studied system for enhancing the overall boiling point of the system. The good initial CO2 solubility and low density of studied solvent system offers several advantages as compared to conventional amine solutions.

  13. Accelerated healing of cutaneous leishmaniasis in non-healing BALB/c mice using water soluble amphotericin B-polymethacrylic acid.

    Science.gov (United States)

    Corware, Karina; Harris, Debra; Teo, Ian; Rogers, Matthew; Naresh, Kikkeri; Müller, Ingrid; Shaunak, Sunil

    2011-11-01

    Cutaneous leishmaniasis (CL) is a neglected tropical disease that causes prominent skin scaring. No water soluble, non-toxic, short course and low cost treatment exists. We developed a new water soluble amphotericin B-polymethacrylic acid (AmB-PMA) using established and scalable chemistries. AmB-PMA was stable for 9 months during storage. In vitro, it was effective against Leishmania spp. promastigotes and amastigote infected macrophages. It was also less toxic and more effective than deoxycholate-AmB, and similar to liposomal AmB. Its in vivo activity was determined in both early and established CL lesion models of Leishmania major infection in genetically susceptible non-healing BALB/c mice. Intradermal AmB-PMA at a total dose of 18 mg of AmB/kg body weight led to rapid parasite killing and lesion healing. No toxicity was seen. No parasite relapse occurred after 80 days follow-up. Histological studies confirmed rapid parasite clearance from macrophages followed by accelerated fibroblast mediated tissue repair, regeneration and cure of the infection. Quantitative mRNA studies of the CL lesions showed that accelerated healing was associated with increased Tumour Necrosis Factor-α and Interferon-γ, and reduced Interleukin-10. These results suggest that a cost-effective AmB-PMA could be used to pharmacologically treat and immuno-therapeutically accelerate the healing of CL lesions. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Inclusion of sunflower seed and wheat dried distillers' grains with solubles in a red clover silage-based diet enhances steers performance, meat quality and fatty acid profiles.

    Science.gov (United States)

    Mapiye, C; Aalhus, J L; Turner, T D; Vahmani, P; Baron, V S; McAllister, T A; Block, H C; Uttaro, B; Dugan, M E R

    2014-12-01

    The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with 15% or 30% wheat dried distillers' grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (Pproducts (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end, t-18:1 isomers, and reduced (Pmeat tenderness. However, in general feeding DGGS-15 or DDGS-30 diets did not change FA proportions relative to feeding the SS diet. Overall, adding SS to a RCS-based diet enhanced muscle proportions of 18:2n-6 biohydrogenation products, and further substitutions of DDGS in the diet improved beef production, and quality while maintaining proportions of potentially functional bioactive FA including vaccenic and rumenic acids.

  15. Different small, acid-soluble proteins of the alpha/beta type have interchangeable roles in the heat and UV radiation resistance of Bacillus subtilis spores

    International Nuclear Information System (INIS)

    Mason, J.M.; Setlow, P.

    1987-01-01

    Spores of Bacillus subtilis strains which carry deletion mutations in one gene (sspA) or two genes (sspA and sspB) which code for major alpha/beta-type small, acid-soluble spore proteins (SASP) are known to be much more sensitive to heat and UV radiation than wild-type spores. This heat- and UV-sensitive phenotype was cured completely or in part by introduction into these mutant strains of one or more copies of the sspA or sspB genes themselves; multiple copies of the B. subtilis sspD gene, which codes for a minor alpha/beta-type SASP; or multiple copies of the SASP-C gene, which codes for a major alpha/beta-type SASP of Bacillus megaterium. These findings suggest that alpha/beta-type SASP play interchangeable roles in the heat and UV radiation resistance of bacterial spores

  16. Absence of transient elevated uv resistance during germination of Bacillus subtilis spores lacking small, acid-soluble spore proteins α and β

    International Nuclear Information System (INIS)

    Setlow, B.; Setlow, P.

    1988-01-01

    Dormant spores of various Bacillus species are much more resistant to UV irradiation than are the corresponding vegetative cells. This elevated spore UV resistance appears to have two causes. First, UV irradiation of spores does not produce the pyrimidine dimers formed in vegetative-cell DNA, but rather produces several other photoproducts, the most predominant of which is termed the spore photoproduct, a 5-thyminyl-5,6-dihydrothymine adduct (1, 10). Second, spores have at least two mechanisms which efficiently repair this spore photoproduct during spore germination, including one which monomerizes the adduct back to two thymines. This study shows that germinating spores of bacillus subtilis mutants which lack small, acid-soluble spore proteins α and β did not exhibit the transient elevated UV resistance seen during germination of wild-type spores

  17. Nondestructive quantification of the soluble-solids content and the available acidity of apples by Fourier-transform near-infrared spectroscopy

    Science.gov (United States)

    Ying, Yibin; Liu, Yande; Tao, Yang

    2005-09-01

    This research evaluated the feasibility of using Fourier-transform near-infrared (FT-NIR) spectroscopy to quantify the soluble-solids content (SSC) and the available acidity (VA) in intact apples. Partial least-squares calibration models, obtained from several preprocessing techniques (smoothing, derivative, etc.) in several wave-number ranges were compared. The best models were obtained with the high coefficient determination (r) 0.940 for the SSC and a moderate r of 0.801 for the VA, root-mean-square errors of prediction of 0.272% and 0.053%, and root-mean-square errors of calibration of 0.261% and 0.046%, respectively. The results indicate that the FT-NIR spectroscopy yields good predictions of the SSC and also showed the feasibility of using it to predict the VA of apples.

  18. Nondestructive quantification of the soluble-solids content and the available acidity of apples by Fourier-transform near-infrared spectroscopy

    International Nuclear Information System (INIS)

    Ying Yibin; Liu Yande; Tao Yang

    2005-01-01

    This research evaluated the feasibility of using Fourier-transform near-infrared (FT-NIR) spectroscopy to quantify the soluble-solids content (SSC) and the available acidity (VA) in intact apples. Partial least-squares calibration models, obtained from several preprocessing techniques (smoothing, derivative, etc.) in several wave-number ranges were compared. The best models were obtained with the high coefficient determination (r 2 ) 0.940 for the SSC and a moderate r 2 of 0.801 for the VA, root-mean-square errors of prediction of 0.272% and 0.053%, and root-mean-square errors of calibration of 0.261% and 0.046%, respectively. The results indicate that the FT-NIR spectroscopy yields good predictions of the SSC and also showed the feasibility of using it to predict the VA of apples

  19. Cofortification of ferric pyrophosphate and citric acid/trisodium citrate into extruded rice grains doubles iron bioavailability through in situ generation of soluble ferric pyrophosphate citrate complexes.

    Science.gov (United States)

    Hackl, Laura; Cercamondi, Colin I; Zeder, Christophe; Wild, Daniela; Adelmann, Horst; Zimmermann, Michael B; Moretti, Diego

    2016-05-01

    Iron fortification of rice is a promising strategy for improving iron nutrition. However, it is technically challenging because rice is consumed as intact grains, and ferric pyrophosphate (FePP), which is usually used for rice fortification, has low bioavailability. We investigated whether the addition of a citric acid/trisodium citrate (CA/TSC) mixture before extrusion increases iron absorption in humans from FePP-fortified extruded rice grains. We conducted an iron absorption study in iron-sufficient young women (n = 20), in which each participant consumed 4 different meals (4 mg Fe/meal): 1) extruded FePP-fortified rice (No CA/TSC); 2) extruded FePP-fortified rice with CA/TSC added before extrusion (CA/TSC extruded); 3) extruded FePP-fortified rice with CA/TSC solution added after cooking and before consumption (CA/TSC solution); and 4) nonextruded rice fortified with a FeSO4 solution added after cooking and before consumption (reference). Iron absorption was calculated from erythrocyte incorporation of stable iron isotopes 14 d after administration. In in vitro experiments, we assessed the soluble and dialyzable iron from rice meals in which CA/TSC was added at different preparation stages and from meals with different iron:CA:TSC ratios. Fractional iron absorption was significantly higher from CA/TSC-extruded meals (3.2%) than from No CA/TSC (1.7%) and CA/TSC solution (1.7%; all P solubility and dialyzability were higher in CA/TSC-extruded rice than in rice with No CA/TSC and CA/TSC solution, and solubility increased with higher amounts of added CA and TSC in extruded rice. Iron bioavailability nearly doubled when CA/TSC was extruded with FePP into fortified rice, resulting in iron bioavailability comparable to that of FeSO4 We attribute this effect to an in situ generation of soluble FePP citrate moieties during extrusion and/or cooking because of the close physical proximity of FePP and CA/TSC in the extruded rice matrix. This trial was registered at

  20. Thermodynamic modeling of acidic gas solubility in aqueous solutions of MEA, MDEA and MEA-MDEA blends

    DEFF Research Database (Denmark)

    Vrachnos, Ath.; Kontogeorgis, Georgios; Voutsas, EC

    2006-01-01

    and extended in this study to the absorption of carbon dioxide into aqueous monoethanolamine (MEA) solutions and aqueous MDEA-MEA blends. The results of the model are compared with experimental data taken from the literature. Very satisfactory predictions of acidic gas vapor-liquid equilibrium over MDEA, MEA...

  1. Incorporating Pitzer equations in a new thermodynamic model for the prediction of acid gases solubility in aqueous alkanolamine solutions

    NARCIS (Netherlands)

    Alhseinat, E.; Mota Martinez, M.; Peters, C.J.; Banat, F.

    2014-01-01

    In gas sweetening, acid gases such as CO2 and/or H2S are usually removed by "chemical" absorption through aqueous amine solutions such as N-Methyldiethanolamine (MDEA) solution. Reliable prediction of equilibrium properties (vapor–liquid equilibrium and species distribution) is needed for a rigorous

  2. Effects of soaking, germination and fermentation on phytic acid, total and in vitro soluble zinc in brown rice

    NARCIS (Netherlands)

    Liang, J.; Han, B.Z.; Nout, M.J.R.; Hamer, R.J.

    2008-01-01

    Rice is an important staple food in Asian countries. In rural areas it is also a major source of micronutrients. Unfortunately, the bioavailability of minerals, e.g. zinc from rice, is low because it is present as an insoluble complex with food components such as phytic acid. We investigated the

  3. Chemical characteristics and acidity of soluble organic substances from a northern hardwood forest floor, central Maine, USA

    International Nuclear Information System (INIS)

    Vance, G.F.; David, M.B.

    1991-01-01

    The authors understanding of the chemistry, structure, and reactions of organic substances in forest floor leachates is limited and incomplete. Therefore, the authors examined the organic and inorganic chemistry of forest floor leachates collected from a hardwood forest in central Maine over a two-year period (1987-1989), including detailed study of dissolved organic carbon (DOC). Seasonal variations in NH 4 + , NO 3 - , K + , and total Al were believed due to organic matter decomposition and release. Leaching of other base cations closely followed that of NO 3 - . Total DOC ranged from 2,228 to 7,193 μmol L -1 with an average of 4,835 μmol L -1 . Monosaccharides and polyphenols constituted 3.9% (range of 3.4 to 4.4%) and 3.0% (2.2 to 3.7%) of the DOC, respectively, which suggests DOC may contain partially oxidized products that are possibly of a lignocellulose nature. Fractionation of the forest floor DOC indicated high organic acid contents (hydrophobic and hydrophilic acids) that averaged 92% of the total DOC. Organic acids were isolated and analyzed for elemental content (C, H, N, and S), and determination of UV absorptivity (E 4 /E 6 ) ratios, CuO oxidation products, FT-IR and 13 C-NMR spectra, and acidity by potentiometric titration. Their FT-IR and 13 C-NMR spectra suggest they are primarily carboxylic acids, with aliphatic and aromatic structure. An organic charge contribution model was developed using titration data, DOC fractionation percentages, and the total DOC in the forest floor leachates. Application of the model to all solutions accounted for 97% of the charge balance deficits

  4. SOLUBILITIES AND PHYSICAL PROPERTIES OF SATURATED SOLUTIONS IN THE COPPER SULFATE + SULFURIC ACID + SEAWATER SYSTEM AT DIFFERENT TEMPERATURES

    OpenAIRE

    Justel, F. J.; Claros, M.; Taboada, M. E.

    2015-01-01

    Abstract In Chile, the most important economic activity is mining, concentrated in the north of the country. This is a desert region with limited water resources; therefore, the mining sector requires research and identification of alternative sources of water. One alternative is seawater, which can be a substitute of the limited fresh water resources in the region. This work determines the influence of seawater on the solid-liquid equilibrium for acid solutions of copper sulfate at different...

  5. One-electron redox reactions of water-soluble vitamins. IV. Thiamin (vitamin B1), biotin, and pantothenic acid

    International Nuclear Information System (INIS)

    Moorthy, P.N.; Hayon, E.

    1977-01-01

    The technique of pulse radiolysis and kinetic absorption spectrophotometry was used to study the one-electron reduction of thiamin, thiazole, 4-aminopyrimidine, biotin, and pantothenic acid in aqueous solution. The acetone ketyl radical and e/sub aq/ - were used as the one-electron reducing agents. The reaction rate constants of e/sub aq/ - and (CH 3 ) 2 COH with these compounds were determined at different pH values, taking into account the dissociation constants of the substrates. The transient optical absorption spectra of the intermediates produced, their extinction coefficients, decay kinetics, and ionization constants were determined. One-electron reduction of the thiazolium ring of thiamin is suggested, based on the formation of dihydrothiamin as a final product. Other assignments for these radicals are suggested and discussed. The reaction of OH radicals with biotin and pantothenic acid leads, primarily, to H atom abstraction at various sites in the molecule. The formation and ionization of the -C(OH)CONH- radical from pantothenic acid, pK/sub a/ = 6.0 +- 0.3, is proposed

  6. Hydrogen Production and Storage on a Formic Acid/Bicarbonate Platform using Water-Soluble N-Heterocyclic Carbene Complexes of Late Transition Metals.

    Science.gov (United States)

    Jantke, Dominik; Pardatscher, Lorenz; Drees, Markus; Cokoja, Mirza; Herrmann, Wolfgang A; Kühn, Fritz E

    2016-10-06

    The synthesis and characterization of two water-soluble bis-N-heterocyclic carbene (NHC) complexes of rhodium and iridium is presented. Both compounds are active in H 2 generation from formic acid and in hydrogenation of bicarbonate to formate. The rhodium derivative is most active in both reactions, reaching a TOF of 39 000 h -1 and a TON of 449 000 for H 2 production. The catalytic hydrogenation reactions were carried out in an autoclave system and analyzed using the integrated peak areas in the 1 H NMR spectra. Decomposition of formic acid was investigated using a Fisher-Porter bottle equipped with a pressure transducer. Long-term stability for hydrogen evolution was tested by surveillance of the gas flow rate. The procedure does not require any additives like amines or inert gas conditions. Density functional theory calculations in agreement with experimental results suggest a bicarbonate reduction mechanism involving a second catalyst molecule, which provides an external hydride acting as reducing agent. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Standardized Ileal Amino Acid Digestibility of Corn, Corn Distillers' Dried Grains with Solubles, Wheat Middlings, and Bakery By-Products in Broilers and Laying Hens.

    Science.gov (United States)

    Adedokun, S A; Jaynes, P; Payne, R L; Applegate, T J

    2015-10-01

    Standardized ileal amino acid digestibility (SIAAD) of 5 samples of corn distillers dried grain with solubles (DDGS), 5 samples of bakery by-products (BBP), 3 samples of corn, and 1 sample of wheat middlings (WM) were evaluated in broilers and laying hens. Diets containing each of the 14 feed ingredients were evaluated in 21 day-old broiler chickens. The DDGS and BBP containing diets were fed to 30-week-old laying hens, while corn and wheat middling were evaluated in 50-week-old laying hens. All the diets were semi-purified with each feed ingredient being the only source of amino acid (AA). To obtain SIAAD values, apparent ileal AA digestibility was corrected for basal ileal endogenous AA losses using values generated from broilers and laying hens fed a nitrogen-free diet. Ileal crude protein digestibility for the 5 DDGS samples was higher (P digestibility values for broilers were higher (P digestibility for corn 1 was higher (P digestibility exists between different samples of DDGS. Differences in SIAAD between broilers and laying hens were observed in some samples of DDGS and BBP. © 2015 Poultry Science Association Inc.

  8. SOLVENT EFFECTS ON THE HYDRATION OF CYCLOHEXENE CATALYZED BY A STRONG ACID ION-EXCHANGE RESIN .1. SOLUBILITY OF CYCLOHEXENE IN AQUEOUS SULFOLANE MIXTURES

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    The solubility of cyclohexene in different water-sulfolane mixtures was measured between 313 and 413 K. The results demonstrate a sharp increase of the solubility of cyclohexene with increasing percentages of sulfolane in the solvent mixture. Without sulfolane the increase of the solubility with

  9. Cocrystals of a 1,2,4-thiadiazole-based potent neuroprotector with gallic acid: solubility, thermodynamic stability relationships and formation pathways.

    Science.gov (United States)

    Surov, Artem O; Churakov, Andrei V; Proshin, Alexey N; Dai, Xia-Lin; Lu, Tongbu; Perlovich, German L

    2018-05-30

    Three distinct solid forms, namely anhydrous cocrystals with 2 : 1 and 1 : 1 drug/acid ratios ([TDZ : GA] (2 : 1), [TDZ : GA] (1 : 1)), and a hydrated one having 1 : 1 : 1 drug/acid/water stoichiometry ([TDZ : GA : H2O] (1 : 1 : 1)), have been formed by cocrystallization of the biologically active 1,2,4-thiadiazole derivative (TDZ) with gallic acid (GA). The thermodynamic stability relationships between the cocrystals were rationalized in terms of Gibbs energies of the formation reactions and further verified by performing a set of competitive and exchange mechanochemical reactions. Interestingly, competitive grinding in the presence of the structurally related vanillic acid led to the formation of a new polymorphic form of the [TDZ : Vanillic acid] (1 : 1) cocrystal, which was promoted by gallic acid. The mechanochemical method was also applied to elucidate the alternative pathways of the [TDZ : GA : H2O] (1 : 1 : 1) cocrystal formation. Direct cocrystallization of TDZ with GA monohydrate was found to proceed much faster than the reaction of TDZ and anhydrous GA in the presence of an acetonitrile/water mixture, which may indicate the presence of a transitional stage. According to dissolution studies, the [TDZ : GA : H2O] (1 : 1 : 1) cocrystal was ca. 6.6 times more soluble than the parent 1,2,4-thiadiazole at pH 2.0 and 25.0 °C. The apparent two-step dehydration behavior of the [TDZ : GA : H2O] (1 : 1 : 1) cocrystal monohydrate was clarified by analyzing the intermolecular interactions of water molecules with the crystalline environment derived from solid state DFT calculations.

  10. Mechanistic studies of the oxidation of soluble species of ruthenium in nitric acid solutions. Application to the removal of ruthenium from nuclear fuel dissolution solutions

    International Nuclear Information System (INIS)

    Carron, V.

    2001-01-01

    Ruthenium is one of the most troublesome fission products during nuclear fuel reprocessing. His removal from nitric acid fuel dissolution solutions, above the PUREX process, is under consideration. Electro-volatilization could be a possible way to eliminate this element. It consists in the oxidation of soluble ruthenium species coupled with the volatilization of formed RuO 4 . Soluble species are nitrate and nitro complexes of nitrosyl ruthenium RuNO 3+ . The first part of this work deals with the direct oxidation of RuNO 3+ at a golden or a platinum anode. It has been investigated by cyclic voltammetry and infrared and UV-visible reflectance spectroscopy. The oxidation of RuNO 3+ begins with an adsorption step, which precedes the formation of RuO 4 . Then a reaction between RuO 4 and RuNO 3+ occurs to produce a Ru IV compound, which is also electro-oxidized to RuO 4 . The second part concerns potentiostatic electro-volatilization experiences. The rate of electro-volatilization decreases with increasing HNO 3 concentration. At low concentrations, kinetic is controlled by the volatilization of RuO 4 . The rate-determining step is the oxidation of RuNO 3+ at concentrations higher than 1 M. In HNO 3 4 M, the addition of AgNO 3 is required to accelerate the oxidation of RuNO 3+ . The last part is devoted to the study of the indirect oxidation of RuNO 3+ . The electrocatalytic power of electro-generated Ag II is illustrated by voltammetric techniques and potentiostatic electrolysis. The existence of a limit concentration of AgNO 3 is shown (which value depends on experimental conditions) beyond which kinetic is controlled by the RuO 4 volatilization step. These results indicate that the electro-volatilization kinetic could be increased by optimizing the volatilization conditions. (author)

  11. Thermodynamic data for modeling acid mine drainage problems: compilation and estimation of data for selected soluble iron-sulfate minerals

    Science.gov (United States)

    Hemingway, Bruch S.; Seal, Robert R.; Chou, I-Ming

    2002-01-01

    Enthalpy of formation, Gibbs energy of formation, and entropy values have been compiled from the literature for the hydrated ferrous sulfate minerals melanterite, rozenite, and szomolnokite, and a variety of other hydrated sulfate compounds. On the basis of this compilation, it appears that there is no evidence for an excess enthalpy of mixing for sulfate-H2O systems, except for the first H2O molecule of crystallization. The enthalpy and Gibbs energy of formation of each H2O molecule of crystallization, except the first, in the iron(II) sulfate - H2O system is -295.15 and -238.0 kJ?mol-1, respectively. The absence of an excess enthalpy of mixing is used as the basis for estimating thermodynamic values for a variety of ferrous, ferric, and mixed-valence sulfate salts of relevance to acid-mine drainage systems.

  12. Effects of non-covalent interactions with 5-O-caffeoylquinic acid (chlorogenic acid) on the heat denaturation and solubility of globular proteins

    NARCIS (Netherlands)

    Prigent, S.V.E.; Gruppen, H.; Visser, A.J.W.G.; Koningsveld, G.A. van; Jong, G.A.H. de; Voragen, A.G.J.

    2003-01-01

    The non-covalent interactions between the monomeric phenolic compound chlorogenic acid (5-CQA) and bovine serum albumin (BSA), lysozyme, and α-lactalbumin were characterized, and their effect on protein properties was examined. 5-CQA had a low affinity for all three proteins, and these interactions

  13. Instrumental neutron activation analysis as a tool for assessing the solubility of soil mineral matter in strong acid

    International Nuclear Information System (INIS)

    Steinnes, E.; Naeumann, R.

    2004-01-01

    Fifty samples of natural surface soils with high but variable organic matter content were analyzed for 13 elements (Na, Al, K, Sc, V, Cr, Mn, Fe, Co, Zn, Sr, Ba, La) by INAA. The same samples were analyzed for the 'total-recoverable' fraction of these elements by ICP-OES after decomposition with 7M HNO 3 , and the results are compared. The data are discussed separately for two groups of samples with organic matter contents of respectively >80% and Mn (77)>La (60)>Fe = Zn (53)>V (33)>Cr (29)>Sc (25)>Al = Ba (17)>Sr (13)>K (5)>Na (2). The results are in good agreement with corresponding literature data for mineral soils in the case of Al, K, Sc, V, Cr, Fe, and La. In the case of Na, Mn, Co, Zn, Sr, and Ba the present surface soils showed significantly higher 'total-recoverable' fractions than the previously studied subsoils. Possible reasons for these differences are discussed. INAA remains a convenient reference technique for determination of total concentrations with the rapidly increasing use of strong mineral acids in environmental studies of elements. (author)

  14. An attempt to calculate in silico disintegration time of tablets containing mefenamic acid, a low water-soluble drug.

    Science.gov (United States)

    Kimura, Go; Puchkov, Maxim; Leuenberger, Hans

    2013-07-01

    Based on a Quality by Design (QbD) approach, it is important to follow International Conference on Harmonization (ICH) guidance Q8 (R2) recommendations to explore the design space. The application of an experimental design is, however, not sufficient because of the fact that it is necessary to take into account the effects of percolation theory. For this purpose, an adequate software needs to be applied, capable of detecting percolation thresholds as a function of the distribution of the functional powder particles. Formulation-computer aided design (F-CAD), originally designed to calculate in silico the drug dissolution profiles of a tablet formulation is, for example, a suitable software for this purpose. The study shows that F-CAD can calculate a good estimate of the disintegration time of a tablet formulation consisting of mefenamic acid. More important, F-CAD is capable of replacing expensive laboratory work by performing in silico experiments for the exploration of the formulation design space according to ICH guidance Q8 (R2). As a consequence, a similar workflow existing as best practice in the automotive and aircraft industry can be adopted by the pharmaceutical industry: The drug delivery vehicle can be first fully designed and tested in silico, which will improve the quality of the marketed formulation and save time and money. Copyright © 2013 Wiley Periodicals, Inc.

  15. Cadmium affects the mitochondrial viability and the acid soluble thiols concentration in liver, kidney, heart and gills of Ancistrus brevifilis (Eigenmann, 1920

    Directory of Open Access Journals (Sweden)

    P. Velasquez-Vottelerd

    2015-11-01

    Full Text Available The freshwater fish Ancistrus brevifilis, which is found in Venezuelan rivers, is considered a potential sentinel fish in ecotoxicological studies. The cadmium (Cd effect on the mitochondrial viability (MV and acid soluble thiols levels (AST in A. brevifilis tissues (liver, kidney, heart, and gill was evaluated. Forty-two fish with similar sizes and weights were randomly selected, of which 7 fish (with their respective replicate were exposed for 7 and 30 days to a Cd sublethal concentration (0.1 mg.l-1. We determined the MV through a Janus Green B colorimetric assay and we obtained the concentration of AST by Ellman’s method. Mitochondrial viability decreased in fish exposed to Cd for 30 days with the liver being the most affected tissue. We also detected a significant decrease in AST levels was in fishes exposed to Cd for 7 days in liver and kidney tissues; these results suggests that AST levels are elevated in some tissues may act as cytoprotective and adaptive alternative mechanism related to the ROS detoxification, maintenance redox status and mitochondrial viability. Organ-specifics variations were observed in both assays. We conclude that the Cd exposure effect on AST levels and MV, vary across fish tissues and is related to the exposure duration, the molecule dynamics in different tissues, the organism and environmental conditions.

  16. Synthesis of a Bacillus subtilis small, acid-soluble spore protein in Escherichia coli causes cell DNA to assume some characteristics of spore DNA

    International Nuclear Information System (INIS)

    Setlow, B.; Hand, A.R.; Setlow, P.

    1991-01-01

    Small, acid-soluble proteins (SASP) of the alpha/beta-type are associated with DNA in spores of Bacillus subtilis. Induction of synthesis of alpha/beta-type SASP in Escherichia coli resulted in rapid cessation of DNA synthesis, followed by a halt in RNA and then protein accumulation, although significant mRNA and protein synthesis continued. There was a significant loss in viability associated with SASP synthesis in E. coli: recA+ cells became extremely long filaments, whereas recA mutant cells became less filamentous. The nucleoids of cells with alpha/beta-type SASP were extremely condensed, as viewed in both light and electron microscopes, and immunoelectron microscopy showed that the alpha/beta-type SASP were associated with the cell DNA. Induction of alpha/beta-type SASP synthesis in E. coli increased the negative superhelical density of plasmid DNA by approximately 20%; UV irradiation of E. coli with alpha/beta-type SASP gave reduced yields of thymine dimers but significant amounts of the spore photoproduct. These changes in E. coli DNA topology and photochemistry due to alpha/beta-type SASP are similar to the effects of alpha/beta-type SASP on the DNA in Bacillus spores, further suggesting that alpha/beta-type SASP are a major factor determining DNA properties in bacterial spores

  17. Student certainty answering misconception question: study of Three-Tier Multiple-Choice Diagnostic Test in Acid-Base and Solubility Equilibrium

    Science.gov (United States)

    Ardiansah; Masykuri, M.; Rahardjo, S. B.

    2018-04-01

    Students’ concept comprehension in three-tier multiple-choice diagnostic test related to student confidence level. The confidence level related to certainty and student’s self-efficacy. The purpose of this research was to find out students’ certainty in misconception test. This research was quantitative-qualitative research method counting students’ confidence level. The research participants were 484 students that were studying acid-base and equilibrium solubility subject. Data was collected using three-tier multiple-choice (3TMC) with thirty questions and students’ questionnaire. The findings showed that #6 item gives the highest misconception percentage and high student confidence about the counting of ultra-dilute solution’s pH. Other findings were that 1) the student tendency chosen the misconception answer is to increase over item number, 2) student certainty decreased in terms of answering the 3TMC, and 3) student self-efficacy and achievement were related each other in the research. The findings suggest some implications and limitations for further research.

  18. Faecal short chain fatty acids in healthy subjects participating in a randomised controlled trial examining a soluble highly viscous polysaccharide versus control.

    Science.gov (United States)

    Reimer, R A; Pelletier, X; Carabin, I G; Lyon, M R; Gahler, R J; Wood, S

    2012-08-01

    Short chain fatty acids (SCFA) are produced by the bacterial fermentation of dietary fibre and have been linked with intestinal health. The present study examined faecal SCFA concentrations in subjects consuming a novel soluble highly viscous polysaccharide (HVP) or control for 3 weeks. A total of 54 healthy adults participated in a randomised, double-blind, placebo-controlled study. Subjects were randomised to consume HVP or control (skim milk powder). A dose of 5 g day(-1) was consumed in the first week, followed by 10 g day(-1) in the second and third weeks (n = 27 per group). The primary outcome was SCFA concentrations in faecal samples collected at baseline (visit 1, V1), at 1 week (V2) and at 3 week (V3). The reduction in faecal acetate from V1 to V3 in control subjects was not observed in subjects consuming HVP. There were no differences in propionate, butyrate, valerate or caproate concentrations. There was a significant treatment effect (P = 0.03) for total SCFA, with higher concentrations observed in subjects consuming HVP versus control. HVP is a viscous functional fibre that may influence gut microbial fermentation. Further work is warranted to examine the fermentative properties of HVP and possible links with appetite regulation and reduced serum low-density lipoprotein cholesterol concentrations. © 2012 The Authors. Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

  19. Study of NSILA-s (nonsuppressible insulin-like activity soluble in acid ethanol) by a new radio-receptor assay

    International Nuclear Information System (INIS)

    Megyeri, K.

    1977-01-01

    The insulin-like activity nonsuppressible with insulin-antibodies (NSILA) accounts for 90% of the insulin activity of the blood plasma. A peptid, soluble in acid ethanol, was purified (NSILA-s) and specific NSILA-s receptors were found on the plasma membrane of liver cells. The specificity, kinetics, affinity and pH-optimum of NSILA-s receptors significantly differed from those of insulin-receptors. A new, highly specific radio-receptor assay was developed, applying 125 I NSILA-s and liver cell membranes or lymphocytes. By this means the NSILA-s concentration of blood plasma was determined under normal and pathological (hypoglycaemizing tumours, hypopituritarism, acromegaly, anorexia nervosa, etc.) conditions. It is concluded that, 90% of the NSILA-s concentration of blood plasma is bound. In cases of hypoglycaemizing tumours increased NSILA-s activity was demonstrated both in blood serum and in the extracts of the tumour-tissue. Pharmacological doses of growth hormon (GH) increased plasma NSILA-s concentration, however, in the case of stimulation- and inhibition-tests carried out in normal patients, no unambiguous relationship could be demonstrated between plasma GH- and NSILA-s-levels. (L.E.)

  20. A spectroscopic study of water-soluble pyronin B and pyronin Y in Langmuir-Blodgett films mixed with stearic acid

    International Nuclear Information System (INIS)

    Meral, Kadem; Erbil, H. Yıldırım; Onganer, Yavuz

    2011-01-01

    Mono and multilayer of water-soluble pyronin B (PyB) and pyronin Y (PyY) mixed with stearic acid (SA) have been incorporated in Langmuir-Blodgett (LB) films. The surface pressure-area (π-A) isotherm studies pointed out that pure PyB and PyY are incapable of forming stable films at air-water interface and collapsed readily at low surface pressures. However, mixture of PyB or PyY with SA easily formed stable films at the air-water interface and they were easily transferred onto solid substrates. The average area per molecule of mixed films of PyB and PyY at the air-water interface was observed to decrease with increasing concentrations of PyB and PyY. The spectroscopic characteristics of PyB and PyY in chloroform, in SA containing chloroform and in LB films have also been investigated by using absorption and steady-state and time-resolved fluorescence spectroscopy techniques. The morphology of the LB film surfaces has been characterized by using atomic force microscopy (AFM).

  1. A spectroscopic study of water-soluble pyronin B and pyronin Y in Langmuir-Blodgett films mixed with stearic acid

    Energy Technology Data Exchange (ETDEWEB)

    Meral, Kadem [Department of Chemistry, Faculty of Sciences, Atatuerk University, 25240 Erzurum (Turkey); Erbil, H. Y Latin-Small-Letter-Dotless-I ld Latin-Small-Letter-Dotless-I r Latin-Small-Letter-Dotless-I m [Department of Chemical Engineering, Gebze Institute of Technology, Cay Latin-Small-Letter-Dotless-I rova, Gebze 41400, Kocaeli (Turkey); Onganer, Yavuz, E-mail: yonganer@atauni.edu.tr [Department of Chemistry, Faculty of Sciences, Atatuerk University, 25240 Erzurum (Turkey)

    2011-12-01

    Mono and multilayer of water-soluble pyronin B (PyB) and pyronin Y (PyY) mixed with stearic acid (SA) have been incorporated in Langmuir-Blodgett (LB) films. The surface pressure-area ({pi}-A) isotherm studies pointed out that pure PyB and PyY are incapable of forming stable films at air-water interface and collapsed readily at low surface pressures. However, mixture of PyB or PyY with SA easily formed stable films at the air-water interface and they were easily transferred onto solid substrates. The average area per molecule of mixed films of PyB and PyY at the air-water interface was observed to decrease with increasing concentrations of PyB and PyY. The spectroscopic characteristics of PyB and PyY in chloroform, in SA containing chloroform and in LB films have also been investigated by using absorption and steady-state and time-resolved fluorescence spectroscopy techniques. The morphology of the LB film surfaces has been characterized by using atomic force microscopy (AFM).

  2. Four Proteins Synthesized in Response to Deoxyribonucleic Acid Damage in Micrococcus Radiodurans

    DEFF Research Database (Denmark)

    Hansen, M. T.

    1980-01-01

    Four proteins, alpha beta, gamma, and delta, preferentially synthesized in ultraviolet light-treated cells of Micrococcus radiodurans, were characterized in terms of their molecular weights and isoelectric points. Within the sublethal-dose range, the differential rate of synthesis for these prote......Four proteins, alpha beta, gamma, and delta, preferentially synthesized in ultraviolet light-treated cells of Micrococcus radiodurans, were characterized in terms of their molecular weights and isoelectric points. Within the sublethal-dose range, the differential rate of synthesis...

  3. Transport properties of poly(GACT)–poly(CTGA) deoxyribonucleic acid

    Indian Academy of Sciences (India)

    interface and the role of tube radius of nanotube contacts on the electronic transmission ... approaches, mostly use strictly one-dimensional tight-binding models [18–21] .... where ΣL(ΣR) is the self-energy matrix resulting from the coupling of the DNA .... where mα and mα run over the interfacial end-atoms of the SWNTs. gα.

  4. Characterization of deoxyribonucleic acid from cells infected with Aleutian disease virus

    International Nuclear Information System (INIS)

    Hahn, E.C.; Ramos, L.; Kenyon, A.J.

    1983-01-01

    Viral DNA was extracted from Crandell feline kidney (CRFK) cells infected with Aleutian disease virus (ADV) and labeled with [ 3 H]thymidine. The sedimentation coefficient in alkaline sucrose gradients was 16S corresponding to a molecular weight of 1.5 X 10(6). The buoyant densities of DNA from infected and control cells were determined by isopyknic sedimentation in CsCl and NaI gradients. Two additional peaks of [ 3 H]DNA were found in infected cells, but not in control cell extracts. Fractionation of this DNA on hydroxylapatite indicated that the new peaks represented a single-stranded component, density 1.728 g/cm3, and a double-stranded component, presumed to be a viral replicative intermediate, density 1.718 g/cm3. The target antigen formation in CRFK cells was measured by gamma-irradiation of ADV and assayed for focus formation. The calculated size of ADV based on these measurements was 1.1 X 10(6). The H-1 parvovirus also was shown to have a size of 1.5 X 10(6) daltons for both antigen and plaque formation. The data indicated similarities existed between ADV and other autonomously replicating parvoviruses in most properties, except that less-than-unit length genome of ADV may be transcribed

  5. Spermine induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assemblies

    NARCIS (Netherlands)

    Göeken, Kristian L.; Schasfoort, Richardus B.M.; Subramaniam, Vinod; Gill, Ron

    DNA-linked 2D and 3D nano-assemblies find use in a diverse set of applications, ranging from DNA-origami in drug delivery and medical imaging, to DNA-linked nanoparticle structures for use in plasmonics and (bio)sensing. However, once these structures have been fully assembled, few options are

  6. Determination of mammalian deoxyribonucleic acid (DNA) in commercial vegetarian and vegan diets for dogs and cats.

    Science.gov (United States)

    Kanakubo, K; Fascetti, A J; Larsen, J A

    2017-02-01

    The determination of undeclared ingredients in pet food using different analytical methods has been reported in recent years, raising concerns regarding adequate quality control, dietary efficacy and the potential for purposeful adulteration. The objective of this study was to determine the presence or absence of mammalian DNA using multiplex polymerase chain reaction (PCR) on diets marketed as vegetarian or vegan for dogs and cats. The diets were tested in duplicate; two samples were purchased approximately 3 to 4 months apart with different lot numbers. Multiplex PCR-targeted mitochondrial DNA with two species-specific primers was used to amplify and sequence two sections of the cytochrome b gene for each of the 11 mammalian species. Half of the diets assessed (7/14) were positive for one or more undeclared mammalian DNA source (bovine, porcine, or ovine), and the result was repeatable for one or more species in six diets. While most of the detected DNA was found at both time points, in some cases, the result was positive only at one time point, suggesting the presence may have been due to unintentional cross-contact with animal-sourced ingredients. DNA from feline, cervine, canine, caprine, equine, murine (mouse and rat) and leporine was not identified in any samples. However, evidence of mammalian DNA does not confirm adulteration by the manufacturer nor elucidate its clinical significance when consumed by animals that may benefit from a vegetarian or vegan diet. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  7. Purification of influenza deoxyribonucleic acid-based vaccine using agmatine monolith.

    Science.gov (United States)

    Bicho, D; Caramelo-Nunes, C; Sousa, A; Sousa, F; Queiroz, J A; Tomaz, C T

    2016-02-15

    Lately, researchers have made several efforts to improve vaccine production to fight highly contagious respiratory diseases like influenza. One of the most promising options for reducing the impact of this virus is DNA vaccination. However, a large quantity of highly pure plasmid DNA (pDNA) is necessary to attain this goal. The present work describes the production and purification of the plasmid NTC7482-41H-VA2HA expressing influenza virus hemagglutinin using an agmatine monolith. This ligand was chosen to purify supercoiled (sc) pDNA from complex lysates because of its versatile multimodal character. Its natural intervention in several biological systems together with its similarity with the highly studied arginine ligand allowed the development of a simpler and more specific purification process. Agmatine works under two strategies: descending ammonium sulfate gradient and ascending sodium chloride gradient. Furthermore, pH manipulation revealed an important role in pDNA isoforms selectivity. Dynamic binding capacity (DBC) experiments were performed varying different parameters and showed an increase with pDNA concentration, while high flow rate and high pH had the opposite effect. Sc pDNA was purified with high yield and was efficient with respect to cell transfection and cell viability. This monolith showed to be appropriate to purify the plasmid NTC7482-41H-VA2HA, providing a valuable tool for pDNA influenza vaccines preparation. Copyright © 2016. Published by Elsevier B.V.

  8. Comprehensive preimplantation genetic screening and sperm deoxyribonucleic acid fragmentation from three males carrying balanced chromosome rearrangements.

    Science.gov (United States)

    Ramos, Laia; Daina, Gemma; Del Rey, Javier; Ribas-Maynou, Jordi; Fernández-Encinas, Alba; Martinez-Passarell, Olga; Boada, Montserrat; Benet, Jordi; Navarro, Joaquima

    2015-09-01

    To assess whether preimplantation genetic screening can successfully identify cytogenetically normal embryos in couples carrying balanced chromosome rearrangements in addition to increased sperm DNA fragmentation. Comprehensive preimplantation genetic screening was performed on three couples carrying chromosome rearrangements. Sperm DNA fragmentation was assessed for each patient. Academic center. One couple with the male partner carrying a chromosome 2 pericentric inversion and two couples with the male partners carrying a Robertsonian translocation (13:14 and 14:21, respectively). A single blastomere from each of the 18 cleavage-stage embryos obtained was analysed by metaphase comparative genomic hybridization. Single- and double-strand sperm DNA fragmentation was determined by the alkaline and neutral Comet assays. Single- and double-strand sperm DNA fragmentation values and incidence of chromosome imbalances in the blastomeres were analyzed. The obtained values of single-strand sperm DNA fragmentation were between 47% and 59%, and the double-strand sperm DNA fragmentation values were between 43% and 54%. No euploid embryos were observed in the couple showing the highest single-strand sperm DNA fragmentation. However, euploid embryos were observed in the other two couples: embryo transfer was performed, and pregnancy was achieved by the couple showing the lowest sperm DNA fragmentation values. Preimplantation genetic screening enables the detection of euploid embryos in couples affected by balanced chromosome rearrangements and increased sperm DNA fragmentation. Even though sperm DNA fragmentation may potentially have clinical consequences on fertility, comprehensive preimplantation genetic screening allows for the identification and transfer of euploid embryos. Copyright © 2015. Published by Elsevier Inc.

  9. Method for detection of a suspect viral deoxyribonucleic acid in an acellular biological fluid

    Energy Technology Data Exchange (ETDEWEB)

    Berninger, M S

    1982-10-06

    A method for evaluating an acellular biological fluid for the presence of a suspect viral DNA, such as DNA of the Hepatitis-B virus, is described. The acellular biological fluid is treated to immobilize in denatured form the DNAs including the suspect viral DNA on a solid substrate. This substrate is contacted with a solution including radioisotopically-labelled suspect viral denatured DNA to renature the immobilized suspect viral native DNA. The solid substrate is then evaluated for radioisotopically-labelled suspect viral renatured DNA.

  10. Method for detection of a suspect viral deoxyribonucleic acid in an acellular biological fluid

    International Nuclear Information System (INIS)

    Berninger, M.S.

    1982-01-01

    A method for evaluating an acellular biological fluid for the presence of a suspect viral DNA, such as DNA of the Hepatitis-B virus, is described. The acellular biological fluid is treated to immobilize in denatured form the DNAs including the suspect viral DNA on a solid substrate. This substrate is contacted with a solution including radioisotopically-labelled suspect viral denatured DNA to renature the immobilized suspect viral native DNA. The solid substrate is then evaluated for radioisotopically-labelled suspect viral renatured DNA. (author)

  11. Isolation of deoxyribonucleic acids (A Review); Aislamiento de los acidos desoxiribonucleicos. Revision Bibliografica

    Energy Technology Data Exchange (ETDEWEB)

    Garcia de Pineda, M de

    1974-07-01

    The criteria of choice in this Review have been to gather some of the last advances in the methodology of DNAs isolation; also the description of the generally accepted procedures has been emphasized. Only papers published before March 1974 are reviewed, because this work has been finished during this month. (Author) 109 refs.

  12. R Factor-Controlled Restriction and Modification of Deoxyribonucleic Acid: Restriction Mutants

    Science.gov (United States)

    Yoshimori, Robert; Roulland-Dussoix, Daisy; Boyer, Herbert W.

    1972-01-01

    Restriction mutants of two different R factor-controlled host specificities (RI and RII) were isolated. All of the restriction mutants examined had a normal modification phenotype. No complementation was observed between the RI and RII host specificities. It is concluded that for each host specificity no protein subunit is shared by the restriction endonuclease and modification methylase. PMID:4565538

  13. Investigation of iron-containing complexes of deoxyribonucleic acid nucleosides by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Greguskova, M.; Novotny, J.; Cernohorsky, I.; Cirak, J.

    1975-01-01

    DNA and nucleoside complexes with ferric and ferrous ions were investigated for the concentration of iron ions, ionic strength, temperature, and the nature and spatial configuration of neighbouring atoms of the iron ions in the complexes. Moessbauer spectroscopy was used. The Moessbauer measurements were conducted on lyophilized samples at room temperature (300 K) and on frozen solutions at liquid nitrogen temperature (77 K). Quadrupole splitting was found in all spectra obtained by a Pd(Co) source, with the exception of thymidine, thus indicating that the formation of complexes had not affected the oxidation state of iron ions. A decrease in isomer shift and an increase in quadrupole splitting were found in all spectra obtained by an iron(III) chloride source as well as in all spectra obtained by an iron chloride tetrahydrate source. UV irradiation of the samples prior to the Moessbauer measurements was found to have no effect on the Moessbauer spectra but to result in changes in the oxidation state of iron ions, mainly their valency and the ferrous/ferric ion ratio. The results are shown in a table and in graphs. (L.O.)

  14. Subnucleosomes and their relationships to the arrangement of histone binding sites along nucleosome deoxyribonucleic acid

    International Nuclear Information System (INIS)

    Nelson, D.A.; Mencke, A.J.; Chambers, S.A.; Oosterhof, D.K.; Rill, R.L.

    1982-01-01

    Micrococcal nuclease cleaves within nucleosomes at sites spaced about 10.4 base pairs (bp) apart. Cleavages at sites equivalent to 30-35 bp from the ends of 146-bp cores cause spontaneous loss of an H2a-H2b pair associated with 30-40 bp length DNA. Cleavages at certain other sites do not affect the nucleosome integrity unless a solvent perturbant such as urea is added. Chromatin moderately digested with micrococcal nuclease, when fractionated by sedimentation or electrophoresis in the presence of 3 M urea, yielded four previously unobserved subnucleosomes with the following histone/DNA compositions: (H3) 2 (H4) 2 (H2a)(H2b)/95-115 bp; (H3)(H4)/70-80 bp DNA; (H2a)(H2b)/50-60 bp DNA; and (H1)/60-70 bp DNA. All but the latter subnucleosome were also obtained upon DNase I digestion of purified nucleosome cores labeled on the 5' ends with 32 P. Only subnucleosomes that retained H2a and H2b also retained labeled ends. These results show that H2a and H2b are paired on the terminal 30-40 bp of core DNA, as suggested from analyses of histone-DNA cross-link products by Mirzabekov and coworkers. Considerations of the orgins and compositions of subnucleosomes and of cross-linking data suggest an expanded model for the locations of histone binding sites along nucleosome core DNA. The principal features of this model are (i) strong electrostatic binding sites of H2a and H2b occur at positions approximately 20-30 bp from the core ends, (ii) strong electrostatic binding sites of H3 and H4 occur primarily on the central 40 bp of core DNA, (iii) strong nonelectrostatic, urea-sensitive binding sites of H3 and H4 occur at positions approximately 30-50 bp from the core ends, and (iv) urea-sensitive binding sites of H2a or H2b may occur on the terminal 10-20 bp of core DNA

  15. Induction of stable protein-deoxyribonucleic acid adducts in Chinese hamster cell chromatin by ultraviolet light

    International Nuclear Information System (INIS)

    Strniste, G.F.; Rall, S.C.

    1976-01-01

    Ultraviolet (uv)-light-mediated formation of protein-DNA adducts in Chinese hamster cell chromatin was investigated in an attempt to compare chromatin alterations induced in vitro with those observed in vivo. Three independent methods of analysis indicated stable protein-DNA associations: a membrane filter assay which retained DNA on the filter in the presence of high salt-detergent; a Sepharose 4B column assay in which protein eluted coincident with DNA; and a CsCl density gradient equilibrium assay which showed both protein and DNA banding at densities other than their respective native densities. Treatment of the irradiated chromatin with DNase provided further evidence that protein--DNA and not protein-protein adducts were being observed in the column assay. There is a fluence-dependent response of protein-DNA adduct formation when the chromatin is irradiated at low ionic strength and is linear for protein over the range studied. When the chromatin is exposed to differing conditions of pH, ionic strength, or divalent metal ion concentration, the quantity of adduct formed upon uv irradiation varies. Susceptibility to adduct formation can be partially explained in terms of the condensation state of the chromatin and other factors such as rearrangement, denaturation, and dissociation of the chromatin components. Besides providing information on the biological significance of these types of uv-induced lesions, this technique may be useful as a probe of chromatin structure

  16. Pellet pestle homogenization of agarose gel slices at 45 degrees C for deoxyribonucleic acid extraction.

    Science.gov (United States)

    Kurien, B T; Kaufman, K M; Harley, J B; Scofield, R H

    2001-09-15

    A simple method for extracting DNA from agarose gel slices is described. The extraction is rapid and does not involve harsh chemicals or sophisticated equipment. The method involves homogenization of the excised gel slice (in Tris-EDTA buffer), containing the DNA fragment of interest, at 45 degrees C in a microcentrifuge tube with a Kontes pellet pestle for 1 min. The "homogenate" is then centrifuged for 30 s and the supernatant is saved. The "homogenized" agarose is extracted one more time and the supernatant obtained is combined with the previous supernatant. The DNA extracted using this method lent itself to restriction enzyme analysis, ligation, transformation, and expression of functional protein in bacteria. This method was found to be applicable with 0.8, 1.0, and 2.0% agarose gels. DNA fragments varying from 23 to 0.4 kb were extracted using this procedure and a yield ranging from 40 to 90% was obtained. The yield was higher for fragments 2.0 kb and higher (70-90%). This range of efficiency was maintained when the starting material was kept between 10 and 300 ng. The heat step was found to be critical since homogenization at room temperature failed to yield any DNA. Extracting DNA with our method elicited an increased yield (up to twofold) compared with that extracted with a commercial kit. Also, the number of transformants obtained using the DNA extracted with our method was at least twice that obtained using the DNA extracted with the commercial kit. Copyright 2001 Academic Press.

  17. Identification of Biological Warfare (BW) Threat Agents Using Deoxyribonucleic Acid (DNA) Microarrays

    National Research Council Canada - National Science Library

    Schaudies, Paul R

    2005-01-01

    ...) antibiotic resistance genes, 4) virulence plasmid sequences and 5) ribosomal genes, we are in a unique position to develop a novel method for the identification and characterization of microorganism...

  18. Studies on the interaction of the food colorant tartrazine with double stranded deoxyribonucleic acid.

    Science.gov (United States)

    Basu, Anirban; Suresh Kumar, Gopinatha

    2016-05-01

    Interaction of the food additive tartrazine with double-stranded DNA was studied by spectroscopic and calorimetric techniques. Absorbance studies revealed that tartrazine exhibited hypochromism in the presence of DNA without any bathochromic effects. Minor groove displacement assay of DAPI and Hoechst 33258 suggested that tartrazine binds in the minor groove of DNA. The complexation was predominantly entropy driven with a smaller but favorable enthalpic contribution to the standard molar Gibbs energy. The equilibrium constant was evaluated to be (3.68 ± .08) × 10(4) M(-1) at 298.15 K. The negative standard molar heat capacity value along with an enthalpy-entropy compensation phenomenon proposed the involvement of dominant hydrophobic forces in the binding process. Tartrazine enhanced the thermal stability of DNA by 7.53 K under saturation conditions.

  19. Inhibition of soluble epoxide hydrolase by cis-4-[4-(3-adamantan-1-ylureido)cyclohexyl-oxy]benzoic acid exhibits antihypertensive and cardioprotective actions in transgenic rats with angiotensin II-dependent hypertension

    Czech Academy of Sciences Publication Activity Database

    Neckář, Jan; Kopkan, L.; Husková, Z.; Kolář, František; Papoušek, František; Kramer, H. J.; Hwang, S.H.; Hammock, B.D.; Imig, J. D.; Malý, J.; Netuka, I.; Ošťádal, Bohuslav; Červenka, L.

    2012-01-01

    Roč. 122, č. 11 (2012), s. 513-525 ISSN 0143-5221 R&D Projects: GA AV ČR(CZ) IAAX01110901; GA AV ČR(CZ) KAN200520703; GA MŠk(CZ) 1M0510 Institutional research plan: CEZ:AV0Z50110509 Keywords : hypertension * angiotensin II * kidney * epoxyeicosatrienoic acids * soluble epoxide hydrolase inhibitor * myocardial ischemia/reperfusion injury Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.859, year: 2012

  20. Acidic gases, ammonia and water-soluble ions in PM 2.5 at a coastal site in the Pearl River Delta, China

    Science.gov (United States)

    Hu, Min; Wu, Zhijun; Slanina, J.; Lin, Peng; Liu, Shang; Zeng, Limin

    Real-time measurements of acidic trace gases (HCl, HNO 3, HONO, and SO 2), ammonia, and water-soluble ions in PM 2.5 were conducted at Xinken, a coastal site downwind of Guangzhou, from 4 October to 4 November 2004, as part of the Pearl River Delta (PRD) intensive field campaign. The average concentrations of HCl, HONO, HNO 3, SO 2, and NH 3 are 2.8, 2.9, 6.3, 55.4, and 7.3 μg m -3, respectively, and 2.4, 7.2, 24.1, and 9.2 μg m -3 for Cl -, NO 3-, SO 42-, and NH 4+ in PM 2.5. The diurnal variations of both HCl and HNO 3 showed higher concentrations during daytime and lower concentrations at night, and aerosol Cl - and NO 3- showed an opposite diurnal patterns to HCl and HNO 3. The diurnal variation of NH 3 showed the similar pattern to that of aerosol NH 4+ with lower concentration during daytime and higher concentration at night. The average concentration of SO 2 during daytime was higher than that at night. The transportation of urban plumes to the sampling site could explain the higher concentration of SO 2 during daytime. HONO showed a clear diurnal variation with lower concentration during daytime and higher concentration at night. The HONO concentrations were positively correlated with the particle surface area concentrations, suggesting the formation of HONO through the heterogeneous conversion on particle surfaces could be significant. The ionic charge balance analysis included the cations derived from filter measurements indicates that the contribution of the cations in fine particle (PM 1.8) to the charge balance is not pronounced. The theoretical equilibrium constant ( Ke) of NH 4NO 3 is higher than the observed concentration product ( Km=[NH 3]×[HNO 3]) during daytime, and lower than Km at night. This indicates that the atmospheric conditions during the sampling period did not favor the formation of NH 4NO 3 during daytime.

  1. Comparison of amino acid digestibility coefficients for corn, corn gluten meal, and corn distillers dried grains with solubles (DDGS) among three different bioassays

    Science.gov (United States)

    The objective of this study was to determine standardized AA digestibility of corn, corn gluten meal (CGM) and three distillers dried grains with solubles (DDGS) using the precision-fed cecectomized rooster assay (PFR), the standardized ileal AA broiler chicken assay (SIAAD), and a newly developed p...

  2. Pretreatment of dried distillers grains with solubles by soaking in aqueous ammonia and subsequent enzymatic/dilute acid hydrolysis to produce fermentable sugars

    Science.gov (United States)

    Dried distillers grains with solubles (DDGS), a co-product of corn ethanol production in the dry-grind process, was pretreated by soaking in aqueous ammonia (SAA) using a 15% w/w NH4OH solution at a solid:liquid ratio of 1:10. The effect of pretreatment on subsequent enzymatic hydrolysis was studied...

  3. Synthesis of freestanding water-soluble indium oxide nanocrystals capped by alanine nitric acid via ligand exchange for thin film transistors and effects of ligands on the electrical properties

    International Nuclear Information System (INIS)

    Choi, Jin-Kyu; Koh, Ye-Seul; Jeong, Hyun-Dam

    2015-01-01

    We demonstrate synthesis of freestanding water-soluble indium oxide nanocrystals (In 2 O 3 NCs) by ligand exchange to β-alanine nitric acid (Ala·HNO 3 ) and its application for active channel layer in thin film transistors (TFTs), with investigation of the effect of curing temperatures on the TFT properties in terms of thermal behaviour of the ligand molecules at 150, 300, and 350 °C. After ligand exchange from long alkyl ligand (myristic acid, MA) to short Ala·HNO 3 , the mobility of NC TFTs cured at 150 °C increased by over 1 order of magnitude, from 1.3 × 10 −4 cm 2 V -1 s −1 to 4.5 × 10 −3 cm 2 V -1 s −1 , due to enhanced tunnelling rate (Γ) between adjective NCs. Higher curing temperatures such as 300 and 350 °C, inducing thermal decomposition of the organic ligands, led to further enhancement of the mobility, particularly up to 2.2 cm 2 V -1 s −1 for the In 2 O 3 NC-Ala·HNO 3 TFT cured at 350 °C. It is also found that the ligand exchange of In 2 O 3 NC in acidic condition (e.g. HNO 3 ) would be simple and effective to reduce the surface defects by surface etching, which may lead to better device performances. - Graphical abstract: Display Omitted - Highlights: • Freestanding water-soluble In 2 O 3 nanocrystals (NCs) were synthesized by ligand exchange. • Thin film transistors (TFTs) of colloidal NCs were fabricated by spin-coating method. • Water-soluble In 2 O 3 NC TFTs showed higher mobilities due to shorter ligand length. • Surface defects of NCs were notably reduced by surface etching during ligand exchange

  4. INTERRELATION OF ACIDITY-BASICITY, SOLUBILITY AND ABILITY TO INTERACTION OF HALIDES OF MX AND M'X2 (M - Li ÷ Cs, M' - Be ÷ Ba, X - Cl ÷ I TYPES

    Directory of Open Access Journals (Sweden)

    V. F. Zinchenko

    2015-11-01

    Full Text Available The size-charge factor of basicity for definition of the acid-base properties of alkaline both alkaline-earth metals and Be halides is offered. The certain interrelation of the specified factor, and also the magnitudes connected with energy of a crystal lattice (temperature of boiling and enthalpy of evaporation of salt with its solubility in water, and also with enthalpy of hydration is established. It is shown that the minimum solubility possess alkaline metals halides (KCl for chlorides, RbBr for Rubidium halides and CsI for alkaline metals halides as a whole at which value of the factor of basicity is equal to 0.83, i.e. it is slightly less than 1. Among alkaline-earth metals halides the lowest solubility has BaCl2 with the highest value of the factor of basicity (0.4. An absolute value of enthalpy of hydration for salts crystal-hydrates possesses tens kJ/mol H2O and increases with reduction of the factor of basicity at transition from metals chlorides to iodides, and also at cationic substitution by easier analogue. Qualitative correlation between a difference of basicity of binary halides and their ability to interaction with formation of complex compounds of various degree of durability is established. At an average difference of basicities 0.4 in halide systems are formed incongruently melting, and at 0.6-0.8 and more – congruently melting compounds. Forecasting of solubility of complex halide of CsSrCl3 composition on the basis of its value of equalized basicity is carried out.

  5. Gas solubilities widespread applications

    CERN Document Server

    Gerrard, William

    1980-01-01

    Gas Solubilities: Widespread Applications discusses several topics concerning the various applications of gas solubilities. The first chapter of the book reviews Henr's law, while the second chapter covers the effect of temperature on gas solubility. The third chapter discusses the various gases used by Horiuti, and the following chapters evaluate the data on sulfur dioxide, chlorine data, and solubility data for hydrogen sulfide. Chapter 7 concerns itself with solubility of radon, thoron, and actinon. Chapter 8 tackles the solubilities of diborane and the gaseous hydrides of groups IV, V, and

  6. Pancreatic beta cells express two autoantigenic forms of glutamic acid decarboxylase, a 65-kDa hydrophilic form and a 64-kDa amphiphilic form which can be both membrane-bound and soluble

    DEFF Research Database (Denmark)

    Christgau, S; Schierbeck, H; Aanstoot, H J

    1991-01-01

    The 64-kDa pancreatic beta-cell autoantigen, which is a target of autoantibodies associated with early as well as progressive stages of beta-cell destruction, resulting in insulin-dependent diabetes (IDDM) in humans, has been identified as the gamma-aminobutyric acid-synthesizing enzyme glutamic...... acid decarboxylase. We have identified two autoantigenic forms of this protein in rat pancreatic beta-cells, a Mr 65,000 (GAD65) hydrophilic and soluble form of pI 6.9-7.1 and a Mr 64,000 (GAD64) component of pI 6.7. GAD64 is more abundant than GAD65 and has three distinct forms with regard to cellular...

  7. Exposure of Atlantic salmon parr (Salmo salar) to a combination of resin acids and a water soluble fraction of diesel fuel oil: A model to investigate the chemical causes of pigmented salmon syndrome

    International Nuclear Information System (INIS)

    Croce, B.; Scottish Environmental Protection Agency, Aberdeen; Stagg, R.M.

    1997-01-01

    Pigmented salmon syndrome is a pollutant-induced hemolytic anemia and hyperbilirubinemia. As part of an investigation of this condition, S2 Atlantic salmon parr (Salmo salar) were exposed to a diesel fuel oil, water soluble fraction (WSF) in combination with a mixture of three resin acids (isopimaric, dehydroabietic, and abietic acids) in a continuous-flow freshwater system. The total nominal concentrations of resin acids in the exposure tanks were 10, 50, and 100 microg/L; the diesel WSF was generated in situ and provided a mean hydrocarbon concentration of 2.0 ± 0.1 mg/L (n = 12) during the 9-d exposure period. Exposure to the diesel WSF alone depressed liver bilirubin UDP-glucuronosyl transferase (UDPGT) activity and induced phenol UDPGT activity. Exposure to the diesel WSF in the absence or presence of resin acids induced liver cytochrome P4501A and increased the concentrations in the plasma of the enzymes lactate dehydrogenase, alkaline phosphatase, and glutamic oxaloacetic transaminase. The combined exposure to diesel WSF with either 50 or 100 microg/L total resin acid caused significant elevations in the concentrations of bilirubin in the plasma and many of these fish had yellow pigmentation on the ventral surface and around the gill arches. The results demonstrate that exposure to combinations of two groups of contaminants can result in the manifestation of toxic effects not apparent from exposure to either of these chemicals in isolation

  8. Water-soluble vitamins.

    Science.gov (United States)

    Konings, Erik J M

    2006-01-01

    Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were based on, for example, LC. Koontz et al. showed results of total folate concentrations measured by microbiological assay in a variety of foods. Samples were submitted in a routine manner to experienced laboratories that regularly perform folate analysis fee-for-service basis in the United States. Each laboratory reported the use of a microbiological method similar to the AOAC Official Method for the determination of folic acid. Striking was, the use of 3 different pH extraction conditions by 4 laboratories. Only one laboratory reported using a tri-enzyme extraction. Results were evaluated. Results for folic acid fortified foods had considerably lower between-laboratory variation, 9-11%, versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. One should realize a large variation in results, which might be caused by slight modifications in the microbiological analysis of total folate in foods or the analysis in various (unfortified) food matrixes. Furthermore, optimal

  9. Non-coding RNA/microRNA-modulatory dietary factors and natural products for improved cancer therapy and prevention: Alkaloids, organosulfur compounds, aliphatic carboxylic acids and water-soluble vitamins

    Directory of Open Access Journals (Sweden)

    Bernhard Biersack

    2016-10-01

    Full Text Available Non-coding small RNA molecules, the microRNAs (miRNAs, contribute decisively to the epigenetic regulation processes in cancer cells. Problematic pathogenic properties of cancer cells and the response of cancers towards anticancer drugs are highly influenced by miRNAs. Both increased drug activity and formation of tumor resistance are regulated by miRNAs. Further to this, the survival and proliferation of cancer cells and the formation of metastases is based on the modulated expression of certain miRNAs. In particular, drug-resistant cancer stem-like cells (CSCs depend on the presence and absence of specific miRNAs. Fortunately, several small molecule natural compounds were discovered that target miRNAs involved in the modulation of tumor aggressiveness and drug resistance. This review gives an overview of the effects of a selection of naturally occurring small molecules (alkaloids, organosulfur compounds, aliphatic carboxylic acids and water-soluble vitamins on miRNAs that are closely tangled with cancer diseases. Keywords: MiRNA, Alkaloids, Organosulfur compounds, Aliphatic carboxylic acids, Water-soluble vitamins, Anticancer drugs

  10. Karyotype and nucleic acid content in Zantedeschia aethiopica Spr ...

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2012-07-03

    Jul 3, 2012 ... Analysis of karyotype, nucleic deoxyribonucleic acid (DNA) content and sodium dodecyl sulfate polyacrylamide ... base pairs) for Z. aethiopica and 1144.26 ± 0.05 picograms (equivalent to 1144.26 mega base pairs) for Z. elliottiana. ... ml ice-cold nuclei-isolation buffer A of the Partec high resolution. DNA kit ...

  11. Influence of calcium and phosphorus, lactose, and salt-to-moisture ratio on Cheddar cheese quality: changes in residual sugars and water-soluble organic acids during ripening.

    Science.gov (United States)

    Upreti, P; McKay, L L; Metzger, L E

    2006-02-01

    Cheddar cheese ripening involves the conversion of lactose to glucose and galactose or galactose-6-phosphate by starter and nonstarter lactic acid bacteria. Under ideal conditions (i.e., where bacteria grow under no stress of pH, water activity, and salt), these sugars are mainly converted to lactic acid. However, during ripening of cheese, survival and growth of bacteria occurs under the stressed condition of low pH, low water activity, and high salt content. This forces bacteria to use alternate biochemical pathways resulting in production of other organic acids. The objective of this study was to determine if the level and type of organic acids produced during ripening was influenced by calcium (Ca) and phosphorus (P), residual lactose, and salt-to-moisture ratio (S/M) of cheese. Eight cheeses with 2 levels of Ca and P (0.67 and 0.47% vs. 0.53 and 0.39%, respectively), lactose at pressing (2.4 vs. 0.78%), and S/M (6.4 vs. 4.8%) were manufactured. The cheeses were analyzed for organic acids (citric, orotic, pyruvic, lactic, formic, uric, acetic, propanoic, and butyric acids) and residual sugars (lactose, galactose) during 48 wk of ripening using an HPLC-based method. Different factors influenced changes in concentration of residual sugars and organic acids during ripening and are discussed in detail. Our results indicated that the largest decrease in lactose and the largest increase in lactic acid occurred between salting and d 1 of ripening. It was interesting to observe that although the lactose content in cheese was influenced by several factors (Ca and P, residual lactose, and S/M), the concentration of lactic acid was influenced only by S/M. More lactic acid was produced in low S/M treatments compared with high S/M treatments. Although surprising for Cheddar cheese, a substantial amount (0.2 to 0.4%) of galactose was observed throughout ripening in all treatments. Minor changes in the levels of citric, uric, butyric, and propanoic acids were observed during

  12. Issues concerning the determination of solubility products of sparingly soluble crystalline solids. Solubility of HfO2(cr)

    International Nuclear Information System (INIS)

    Rai, Dhanpat; Kitamura, Akira; Rosso, Kevin M.; Sasaki, Takayuki; Kobayashi, Taishi

    2016-01-01

    Solubility studies were conducted with HfO 2 (cr) solid as a function HCl and ionic strength ranging from 2.0 to 0.004 mol kg -1 . These studies involved (1) using two different amounts of the solid phase, (2) acid washing the bulk solid phase, (3) preheating the solid phase to 1400 C, and (4) heating amorphous HfO 2 (am) suspensions to 90 C to ascertain whether the HfO 2 (am) converts to HfO 2 (cr) and to determine the solubility from the oversaturation direction. Based on the results of these treatments it is concluded that the HfO 2 (cr) contains a small fraction of less crystalline, but not amorphous, material [HfO 2 (lcr)] and this, rather than the HfO 2 (cr), is the solubility-controlling phase in the range of experimental variables investigated in this study. The solubility data are interpreted using both the Pitzer and SIT models and they provide log 10 K 0 values of -(59.75±0.35) and -(59.48±0.41), respectively, for the solubility product of HfO 2 (lcr)[HfO 2 (lcr) + 2H 2 O ↔ Hf 4+ + 4OH - ]. The log 10 of the solubility product of HfO 2 (cr) is estimated to be < -63. The observation of a small fraction of less crystalline higher solubility material is consistent with the general picture that mineral surfaces are often structurally and/or compositionally imperfect leading to a higher solubility than the bulk crystalline solid. This study stresses the urgent need, during interpretation of solubility data, of taking precautions to make certain that the observed solubility behavior for sparingly-soluble solids is assigned to the proper solid phase.

  13. Issues concerning the determination of solubility products of sparingly soluble crystalline solids. Solubility of HfO{sub 2}(cr)

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Dhanpat [Rai Enviro-Chem, LLC, Yachats, OR (United States); Kitamura, Akira [Japan Atomic Energy Agency, Ibaraki (Japan); Rosso, Kevin M. [Pacific Northwest National Laboratory, Richland, WA (United States); Sasaki, Takayuki; Kobayashi, Taishi [Kyoto Univ. (Japan)

    2016-11-01

    Solubility studies were conducted with HfO{sub 2}(cr) solid as a function HCl and ionic strength ranging from 2.0 to 0.004 mol kg{sup -1}. These studies involved (1) using two different amounts of the solid phase, (2) acid washing the bulk solid phase, (3) preheating the solid phase to 1400 C, and (4) heating amorphous HfO{sub 2}(am) suspensions to 90 C to ascertain whether the HfO{sub 2}(am) converts to HfO{sub 2}(cr) and to determine the solubility from the oversaturation direction. Based on the results of these treatments it is concluded that the HfO{sub 2}(cr) contains a small fraction of less crystalline, but not amorphous, material [HfO{sub 2}(lcr)] and this, rather than the HfO{sub 2}(cr), is the solubility-controlling phase in the range of experimental variables investigated in this study. The solubility data are interpreted using both the Pitzer and SIT models and they provide log{sub 10} K{sup 0} values of -(59.75±0.35) and -(59.48±0.41), respectively, for the solubility product of HfO{sub 2}(lcr)[HfO{sub 2}(lcr) + 2H{sub 2}O ↔ Hf{sup 4+} + 4OH{sup -}]. The log{sub 10} of the solubility product of HfO{sub 2}(cr) is estimated to be < -63. The observation of a small fraction of less crystalline higher solubility material is consistent with the general picture that mineral surfaces are often structurally and/or compositionally imperfect leading to a higher solubility than the bulk crystalline solid. This study stresses the urgent need, during interpretation of solubility data, of taking precautions to make certain that the observed solubility behavior for sparingly-soluble solids is assigned to the proper solid phase.

  14. Influence of iron solubility and charged surface-active compounds on lipid oxidation in fatty acid ethyl esters containing association colloids.

    Science.gov (United States)

    Homma, Rika; Johnson, David R; McClements, D Julian; Decker, Eric A

    2016-05-15

    The impact of iron compounds with different solubilities on lipid oxidation was studied in the presence and absence of association colloids. Iron (III) sulfate only accelerated lipid oxidation in the presence of association colloids while iron (III) oleate accelerated oxidation in the presence and absence of association colloids. Further, iron (III) oxide retarded lipid oxidation both with and without association colloids. The impact of charged association colloids on lipid oxidation in ethyl oleate was also investigated. Association colloids consisting of the anionic surface-active compound dodecyl sulphosuccinate sodium salt (AOT), cationic surface-active compound hexadecyltrimethylammonium bromide (CTAB), and nonionic surface-active compound 4-(1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol (Triton X-100) retarded, promoted, and had no effect on lipid oxidation rates, respectively. These results indicate that the polarity of metal compounds and the charge of association colloids play a big role in lipid oxidation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthesis of freestanding water-soluble indium oxide nanocrystals capped by alanine nitric acid via ligand exchange for thin film transistors and effects of ligands on the electrical properties

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin-Kyu; Koh, Ye-Seul; Jeong, Hyun-Dam, E-mail: hdjeong@chonnam.ac.kr

    2015-07-15

    We demonstrate synthesis of freestanding water-soluble indium oxide nanocrystals (In{sub 2}O{sub 3} NCs) by ligand exchange to β-alanine nitric acid (Ala·HNO{sub 3}) and its application for active channel layer in thin film transistors (TFTs), with investigation of the effect of curing temperatures on the TFT properties in terms of thermal behaviour of the ligand molecules at 150, 300, and 350 °C. After ligand exchange from long alkyl ligand (myristic acid, MA) to short Ala·HNO{sub 3}, the mobility of NC TFTs cured at 150 °C increased by over 1 order of magnitude, from 1.3 × 10{sup −4} cm{sup 2}V{sup -1}s{sup −1} to 4.5 × 10{sup −3} cm{sup 2}V{sup -1}s{sup −1}, due to enhanced tunnelling rate (Γ) between adjective NCs. Higher curing temperatures such as 300 and 350 °C, inducing thermal decomposition of the organic ligands, led to further enhancement of the mobility, particularly up to 2.2 cm{sup 2}V{sup -1}s{sup −1} for the In{sub 2}O{sub 3} NC-Ala·HNO{sub 3} TFT cured at 350 °C. It is also found that the ligand exchange of In{sub 2}O{sub 3} NC in acidic condition (e.g. HNO{sub 3}) would be simple and effective to reduce the surface defects by surface etching, which may lead to better device performances. - Graphical abstract: Display Omitted - Highlights: • Freestanding water-soluble In{sub 2}O{sub 3} nanocrystals (NCs) were synthesized by ligand exchange. • Thin film transistors (TFTs) of colloidal NCs were fabricated by spin-coating method. • Water-soluble In{sub 2}O{sub 3} NC TFTs showed higher mobilities due to shorter ligand length. • Surface defects of NCs were notably reduced by surface etching during ligand exchange.

  16. Polymer brush hexadecyltrimethylammonium bromide (CTAB) modified poly (propylene-g-styrene sulphonic acid) fiber (ZB-1): CTAB/ZB-1 as a promising strategy for improving the dissolution and physical stability of poorly water-soluble drugs.

    Science.gov (United States)

    Cao, Jinxu; Yang, Baixue; Wang, Yumei; Wei, Chen; Wang, Hongyu; Li, Sanming

    2017-11-01

    The feasibility of polymer brush as drug delivery vehicle was demonstrated with the goal of improving the dissolution and physical stability of poorly water-soluble drugs. Polymer brush CTAB/ZB-1 was synthesized by electrostatic interaction using a physical modification method with anionic poly (propylene-g-styrene sulphonic acid) fiber (ZB-1) as the substrate and cationic hexadecyltrimethylammonium bromide (CTAB) as the modifier. The polymer brush structure of CTAB/ZB-1 was validated by atomic force microscopy (AFM) and the channels of brush provided the drug loading sites. Flurbiprofen (FP), a BCS class II representative drug, was selected as the model poorly water-soluble drug to be loaded into this polymer brush. Then the drug loading and release were systematically investigated. Besides, the transformation from crystalline FP to amorphous state was observed by differential scanning calorimeter (DSC). In vitro dissolution in pure water and pH1.2 HCl media with/without 0.1% sodium dodecyl sulfate (SDS) was tested. Moreover, the optimal formulations (namely carrier/drug ratios) were determined. The results demonstrated prominent improvement of dissolution when FP was released from CTAB/ZB-1. After a long time storage, FP remained amorphous in CTAB/ZB-1 according to DSC determinations and performed an approximately equivalent dissolution compared with fresh samples, suggesting the advantage of CTAB/ZB-1 as carrier in enhancing the physical stability of drugs. The study introduced the versatile easily formulated polymer brush CTAB/ZB-1 and demonstrated the potential of polymer brush as an alternative approach for improving the dissolution and physical stability of poorly water-soluble drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Preparation of Water-Soluble Homo and Copolymers of Bithiophene with 3,4-Ethylene Dioxythiophene and 3-Dodecylthiophene in Presence of Polystyrene Sulfonic Acid: Structure, Morphology, Thermal Stability

    Directory of Open Access Journals (Sweden)

    Bakhshali Massoumi

    2015-04-01

    Full Text Available Conductive polymers based on water-soluble polythiophenes were prepared. In this respect, alkylation reaction was carried out to synthesize the monomer 3-dodecylthiophene using 3-bromothiophene, bromododecane and magnesium. The monomer 2,2′-bithiophene was also prepared from 2-bromothiophene. Then, poly(2,2′-bithiophene, poly(3,4-ethylenedioxythiophene and poly(3-dodecylthiophene homopolymers were prepared at room temperature by successive chemical oxidation in the presence of polystyrene sulfonic acid and ammonium persulfate and water, as dopant, oxidant and solvent, respectively, under vigorous stirring. Under similar conditions, 2,2′-bithiophene copolymers with 3-dodecylthiophene and 3,4-ethylenedioxythiophene, copolymers with 3-dodecylthiophene were prepared at different molar ratios. To purify and dry the prepared polymers, dialysis tubs and freezing dry processes were applied. Structure of homo and copolymers were investigated by Fourier transform infrared (FTIR. Conjugated and planar structures of polymers were studied by Ultravoilet (UV-vis spectroscopy. The electrical conductivity of synthesized polymers was measured by four probe technique. The morphology and thermal stability of the products were studied using scanning electron microscopy (SEM, transmission electron microscopy (TEM and thermogravimetric analysis (TGA. Finally, solubility of homo and copolymers were tested in some organic solvents and water. Electro- activity of the prepared polymers was studied by cyclic voltammetry (CV on the glassy carbon (GC in LiClO4/CH3CN electrolyte solution and their electro-activity was confirmed. Electro-conductivity and electro-activity of homo and co polymers were low due topresence of polystyrene sulfonic acid which reduced the immobility of the polymers.

  18. Vorinostat with Sustained Exposure and High Solubility in Poly(ethylene glycol)-b-poly(DL-lactic acid) Micelle Nanocarriers: Characterization and Effects on Pharmacokinetics in Rat Serum and Urine

    Science.gov (United States)

    Mohamed, Elham A.; Zhao, Yunqi; Meshali, Mahasen M.; Remsberg, Connie M.; Borg, Thanaa M.; Foda, Abdel Monem M.; Takemoto, Jody K.; Sayre, Casey; Martinez, Stephanie; Davies, Neal M.; Forrest, M. Laird

    2015-01-01

    The histone deacetylase inhibitor suberoylanilide hydroxamic acid, known as vorinostat, is a promising anti-cancer drug with a unique mode of action; however, it is plagued by low water solubility, low permeability, and suboptimal pharmacokinetics. In this study, poly(ethylene glycol)-b-poly(DL-lactic acid) (PEG-b-PLA) micelles of vorinostat were developed. Vorinostat’s pharmacokinetics in rats were investigated after intravenous (i.v.) (10 mg/kg) and oral (50 mg/kg) micellar administrations and compared to a conventional PEG400 solution and methylcellulose suspension. The micelles increased the aqueous solubility of vorinostat from 0.2 mg/ml to 8.15 ± 0.60 mg/ml and 10.24 ± 0.92 mg/ml at drug to nanocarrier ratios of 1:10 and 1:15, respectively. Micelles had nanoscopic mean diameters of 75.67 ± 7.57 nm and 87.33 ± 8.62 nm for 1:10 and 1:15 micelles, respectively, with drug loading capacities of 9.93 ± 0.21% and 6.91 ± 1.19 %, and encapsulation efficiencies of 42.74 ± 1.67% and 73.29 ± 4.78%, respectively. The micelles provided sustained exposure and improved pharmacokinetics characterized by a significant increase in serum half-life, area under curve, and mean residence time. The micelles reduced vorinostat clearance particularly after i.v. dosing. Thus, PEG-b-PLA micelles significantly improved the oral and intravenous pharmacokinetics and bioavailability of vorinostat, which warrants further investigation. PMID:22806441

  19. Vorinostat with sustained exposure and high solubility in poly(ethylene glycol)-b-poly(DL-lactic acid) micelle nanocarriers: characterization and effects on pharmacokinetics in rat serum and urine.

    Science.gov (United States)

    Mohamed, Elham A; Zhao, Yunqi; Meshali, Mahasen M; Remsberg, Connie M; Borg, Thanaa M; Foda, Abdel Monem M; Takemoto, Jody K; Sayre, Casey L; Martinez, Stephanie E; Davies, Neal M; Forrest, M Laird

    2012-10-01

    The histone deacetylase inhibitor suberoylanilide hydroxamic acid, known as vorinostat, is a promising anticancer drug with a unique mode of action; however, it is plagued by low water solubility, low permeability, and suboptimal pharmacokinetics. In this study, poly(ethylene glycol)-b-poly(DL-lactic acid) (PEG-b-PLA) micelles of vorinostat were developed. Vorinostat's pharmacokinetics in rats was investigated after intravenous (i.v.) (10 mg/kg) and oral (p.o.) (50 mg/kg) micellar administrations and compared with a conventional polyethylene glycol 400 solution and methylcellulose suspension. The micelles increased the aqueous solubility of vorinostat from 0.2 to 8.15 ± 0.60 and 10.24 ± 0.92 mg/mL at drug to nanocarrier ratios of 1:10 and 1:15, respectively. Micelles had nanoscopic mean diameters of 75.67 ± 7.57 and 87.33 ± 8.62 nm for 1:10 and 1:15 micelles, respectively, with drug loading capacities of 9.93 ± 0.21% and 6.91 ± 1.19%, and encapsulation efficiencies of 42.74 ± 1.67% and 73.29 ± 4.78%, respectively. The micelles provided sustained exposure and improved pharmacokinetics characterized by a significant increase in serum half-life, area under curve, and mean residence time. The micelles reduced vorinostat clearance particularly after i.v. dosing. Thus, PEG-b-PLA micelles significantly improved the p.o. and i.v. pharmacokinetics and bioavailability of vorinostat, which warrants further investigation. Copyright © 2012 Wiley Periodicals, Inc.

  20. Processing diets containing corn distillers' dried grains with solubles in growing broiler chickens: effects on performance, pellet quality, ileal amino acids digestibility, and intestinal microbiota.

    Science.gov (United States)

    Kim, J S; Hosseindoust, A R; Shim, Y H; Lee, S H; Choi, Y H; Kim, M J; Oh, S M; Ham, H B; Kumar, A; Chae, B J

    2018-04-03

    The present study investigated the effects of feed form and distillers' dried grains with solubles (DDGS) on growth performance, nutrient digestibility, and intestine microbiota in broilers. A total of 720 broilers (Ross 308; average BW 541 ± 6 g) was randomly allotted to 6 treatments on the basis of BW. There were 6 replicates in each treatment with 20 birds per replicate. Birds were fed 3 different feed forms (mash, simple pellet, and expanded pellet) and DDGS (0 or 20% of diet) in a 3 × 2 factorial arrangement. Simple pellet (SP) and expanded pellet (EP) fed birds showed an increase in BW gain (P digestibility of CP compared to mash feed. The inclusion of DDGS decreased the digestibility of CP, and tended to decrease digestibility of DM (P = 0.056) and gross energy (P = 0.069). Expanded pellet feeding decreased (P digestibility of isoleucine, lysine, methionine, phenylalanine, threonine, cysteine, and glutamine compared with mash diet. Processed feed increased (P digestibility. In addition, DDGS supplementation (20%) decreased pellet quality and CP digestibility in broiler chickens; however, the growth performance and feed intake were not affected.

  1. Auto-assembly of nanometer thick, water soluble layers of plasmid DNA complexed with diamines and basic amino acids on graphite: Greatest DNA protection is obtained with arginine

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, T.T.; Boulanouar, O. [Université de Bourgogne Franche-Comté, UMR CNRS 6249 Chrono-Environnement, 16, Route de Gray, 25030 Besançon Cedex (France); Heintz, O. [Université de Bourgogne Franche-Comté, UMR CNRS 6303Laboratoire Interdisciplinaire Carnot de Bourgogne, DTAI/Centre de micro/nano caractérisation, 9 Av. A. Savary, BP 47870, F-21078 DIJON Cedex (France); Fromm, M., E-mail: michel.fromm@univ-fcomte.fr [Université de Bourgogne Franche-Comté, UMR CNRS 6249 Chrono-Environnement, 16, Route de Gray, 25030 Besançon Cedex (France)

    2017-02-01

    We have investigated the ability of diamines as well as basic amino acids to condense DNA onto highly ordered pyrolytic graphite with minimum damage after re-dissolution in water. Based on a bibliographic survey we briefly summarize DNA binding properties with diamines as compared to basic amino acids. Thus, solutions of DNA complexed with these linkers were drop-cast in order to deposit ultra-thin layers on the surface of HOPG in the absence or presence of Tris buffer. Atomic Force Microscopy analyses showed that, at a fixed ligand-DNA mixing ratio of 16, the mean thickness of the layers can be statistically predicted to lie in the range 0–50 nm with a maximum standard deviation ± 6 nm, using a simple linear law depending on the DNA concentration. The morphology of the layers appears to be ligand-dependent. While the layers containing diamines present holes, those formed in the presence of basic amino acids, except for lysine, are much more compact and dense. X-ray Photoelectron Spectroscopy measurements provide compositional information indicating that, compared to the maximum number of DNA sites to which the ligands may bind, the basic amino acids Arg and His are present in large excess. Conservation of the supercoiled topology of the DNA plasmids was studied after recovery of the complex layers in water. Remarkably, arginine has the best protection capabilities whether Tris was present or not in the initial solution. - Highlights: • Characterization of nanometer scaled layers composed of pUC21 plasmid DNA • Relation between nature of the ligand and structure of the layers • Capacities of the ligands to protect plasmids from strand break depending on their nature.

  2. Lidocaine self-sacrificially improves the skin permeation of the acidic and poorly water-soluble drug etodolac via its transformation into an ionic liquid.

    Science.gov (United States)

    Miwa, Yasushi; Hamamoto, Hidetoshi; Ishida, Tatsuhiro

    2016-05-01

    Poor transdermal penetration of active pharmaceutical ingredients (APIs) impairs both bioavailability and therapeutic benefits and is a major challenge in the development of transdermal drug delivery systems. Here, we transformed a poorly water-soluble drug, etodolac, into an ionic liquid in order to improve its hydrophobicity, hydrophilicity and skin permeability. The ionic liquid was prepared by mixing etodolac with lidocaine (1:1, mol/mol). Both the free drug and the transformed ionic liquid were characterized by differential scanning colorimetry (DSC), infrared spectroscopy (IR), and saturation concentration measurements. In addition, in vitro skin-permeation testing was carried out via an ionic liquid-containing patch (Etoreat patch). The lidocaine and etodolac in ionic liquid form led to a relatively lower melting point than either lidocaine or etodolac alone, and this improved the lipophilicity/hydrophilicity of etodolac. In vitro skin-permeation testing demonstrated that the Etoreat patch significantly increased the skin permeation of etodolac (9.3-fold) compared with an etodolac alone patch, although an Etoreat patch did not increase the skin permeation of lidocaine, which was consistent with the results when using a lidocaine alone patch. Lidocaine appeared to self-sacrificially improve the skin permeation of etodolac via its transformation into an ionic liquid. The data suggest that ionic liquids composed of approved drugs may substantially expand the formulation preparation method to meet the challenges of drugs which are characterized by poor rates of transdermal absorption. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Reduced Solubility of Polymer-Oriented Water for Sodium Salts, Sugars, Amino Acids, and other Solutes Normally Maintained at Low Levels in Living Cells,

    Science.gov (United States)

    1983-01-01

    following were obtained: gum arabic (64C-0252; gum ghatti (42C-2380; gum guar (32C1930); gum Karaya (103C-0720); gum locust bean (42C-2900); gum ...plotted against time of incubation. In the efflux method, usually the dry polymer powder was dissolved 22 + 35 in water containing the radioactive label...tragacanth (74C-0207); and gum xantham (888-0200); corn starch (6813-0216); potato starch (65B-2060); pectin (107B-0090); alginic acid (766-818); also

  4. Intestinal digestibility of amino acids in rumen-undegraded protein estimated using a precision-fed cecectomized rooster bioassay: II. Distillers dried grains with solubles and fish meal.

    Science.gov (United States)

    Boucher, S E; Calsamiglia, S; Parsons, C M; Stein, H H; Stern, M D; Erickson, P S; Utterback, P L; Schwab, C G

    2009-12-01

    The objectives of this experiment were to measure intestinal digestibility of AA in the rumen-undegraded protein fraction (RUP-AA) of distillers dried grains with solubles (DDGS) and fish meal (FM) samples and to determine whether these feeds contain a constant protein fraction that is undegradable in the rumen and indigestible in the small intestine, as assumed in the French Institut National de la Recherche Agronomique (Paris, France) and Scandinavian AAT-PBV (AAT = AA absorbed from small intestine; PBV = protein balance in the rumen) models. Five sources of DDGS and 5 sources of FM were obtained from Feed Analysis Consortium, Inc. (Champaign, IL). To obtain the rumen-undegradable protein fraction, samples were ruminally incubated in situ for 16 h in 4 lactating cows, and the collected rumen-undegraded residues (RUR) were pooled by sample. Subsamples of the intact feeds and RUR were crop-intubated to 4 cecectomized roosters, and total excreta were collected for 48 h. Intact feeds, RUR, and excreta were analyzed for AA. Basal endogenous AA loss estimates were obtained from fasted birds and were used to calculate standardized digestibility of RUP-AA and AA in the intact feeds. Indigestibility coefficients of the intact feeds were calculated as (100 - % standardized AA digestibility), and indigestibility of the RUR was calculated as [(100 - % ruminal degradation of AA) x (100 - % standardized RUP-AA digestibility)/100]. Results indicate that standardized digestibility of feed-AA differs from RUP-AA for DDGS samples but not for FM samples, and that standardized digestibility of individual AA differs within samples. For the DDGS samples, standardized feed-AA and RUP-AA digestibility values were most often lowest for His and Lys and highest for Met and Trp. For FM samples, standardized feed-AA and RUP-AA digestibility values were most often lowest for His and highest for Trp. Results also indicate that DDGS and most FM samples do not contain a constant protein fraction

  5. Soluble γ-secretase modulators selectively inhibit the production of the 42-amino acid amyloid β peptide variant and augment the production of multiple carboxy-truncated amyloid β species.

    Science.gov (United States)

    Wagner, Steven L; Zhang, Can; Cheng, Soan; Nguyen, Phuong; Zhang, Xulun; Rynearson, Kevin D; Wang, Rong; Li, Yueming; Sisodia, Sangram S; Mobley, William C; Tanzi, Rudolph E

    2014-02-04

    Alzheimer's disease (AD) is characterized pathologically by an abundance of extracellular neuritic plaques composed primarily of the 42-amino acid amyloid β peptide variant (Aβ42). In the majority of familial AD (FAD) cases, e.g., those harboring mutations in presenilin 1 (PS1), there is a relative increase in the levels of Aβ42 compared to the levels of Aβ40. We previously reported the characterization of a series of aminothiazole-bridged aromates termed aryl aminothiazole γ-secretase modulators or AGSMs [Kounnas, M. Z., et al. (2010) Neuron 67, 769-780] and showed their potential for use in the treatment of FAD [Wagner, S. L., et al. (2012) Arch. Neurol. 69, 1255-1258]. Here we describe a series of GSMs with physicochemical properties improved compared to those of AGSMs. Specific heterocycle replacements of the phenyl rings in AGSMs provided potent molecules with improved aqueous solubilities. A number of these soluble γ-secretase modulators (SGSMs) potently lowered Aβ42 levels without inhibiting proteolysis of Notch or causing accumulation of amyloid precursor protein carboxy-terminal fragments, even at concentrations approximately 1000-fold greater than their IC50 values for reducing Aβ42 levels. The effects of one potent SGSM on Aβ peptide production were verified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, showing enhanced production of a number of carboxy-truncated Aβ species. This SGSM also inhibited Aβ42 peptide production in a highly purified reconstituted γ-secretase in vitro assay system and retained the ability to modulate γ-secretase-mediated proteolysis in a stably transfected cell culture model overexpressing a human PS1 mutation validating the potential for use in FAD.

  6. Fatty acid composition, fat soluble vitamin concentrations and oxidative stability in bovine milk produced on two pastures with different botanical composition

    DEFF Research Database (Denmark)

    Adler, S A; Dahl, A V; Jensen, Søren Krogh

    2013-01-01

    to oxidation. Two groups of 8 multiparous Norwegian Red dairy cows [mean (standard deviation); 599 (45.1) kg body weight, 73 (15.0) d in milk, 29.9 (2.90) kg milk/d at experiment start] grazed either a short-term pasture (SP) or a long-term pasture (LP). Both pastures were organically managed, meaning......Previous research has shown that grazing pastures compared to feeding preserved forages has large impact on milk fatty acid (FA) composition, but differences between grazing red clover (Trifolium pratense L.) or white clover (Trifolium repens L.) are small, whereas the herbage proportions...... of dicotyledon botanical families is positively correlated with the milk-fat proportions of total polyunsaturated FA when grazing pastures in the Alps. The objective of the present study was to investigate the influence of botanically different pastures on bovine milk composition and milk susceptibility...

  7. Kinetics of corrosion inhibition of aluminum in acidic media by water-soluble natural polymeric chondroitin-4-sulfate as anionic polyelectrolyte inhibitor.

    Science.gov (United States)

    Hassan, Refat M; Ibrahim, Samia M; Takagi, Hideo D; Sayed, Suzan A

    2018-07-15

    Corrosion inhibition of aluminum (Al) in hydrochloric acid by anionic polyelectrolyte chondroitin-4-sulfate (CS) polysaccharide has been studied using both gasometrical and weight-loss techniques. The results drawn from these two techniques are comparable and exhibit negligible differences. The inhibition efficiency was found to increase with increasing the inhibitor concentration and decreased with increasing temperature. The inhibition action of CS on Al metal surface was found to obey both of Langmuir and Freundlich isotherms. The factors affecting the corrosion rates such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and the temperature were examined. The kinetic parameters were evaluated and a suitable corrosion mechanism consistent with the results obtained is discussed. Copyright © 2018. Published by Elsevier Ltd.

  8. Effect of surfactants on the fluorescence spectra of water-soluble ...

    Indian Academy of Sciences (India)

    TECS

    Effect of surfactants on the fluorescence spectra of water-soluble. MEHPPV ... polyacrylic acid (PAA) chains grafted onto their backbone were found to be water soluble, and they exhi- ..... in other words the variation of emission intensity.

  9. Water soluble and efficient amino acid Schiff base receptor for reversible fluorescence turn-on detection of Zn2+ ions: Quantum chemical calculations and detection of bacteria

    Science.gov (United States)

    Subha, L.; Balakrishnan, C.; Natarajan, Satheesh; Theetharappan, M.; Subramanian, Balanehru; Neelakantan, M. A.

    2016-01-01

    An amino acid Schiff base (R) capable of recognizing Zn2+ ions selectively and sensitively in an aqueous medium was prepared and characterized. Upon addition of Zn2+ ions, the receptor exhibits fluorescence intensity enhancements ( 40 fold) at 460 nm (quantum yield, Φ = 0.05 for R and Φ = 0.18 for R-Zn2+) and can be detected by naked eye under UV light. The receptor can recognize the Zn2+ (1.04 × 10- 8 M) selectively for other metal ions in the pH range of 7.5-11. The Zn2+ chelation with R decreases the loss of energy through non-radiative transition and leads to fluorescence enhancement. The binding mode of the receptor with Zn2+ was investigated by 1H NMR titration and further validated by ESI-MS. The elemental color mapping and SEM/EDS analysis were also used to study the binding of R with Zn2+. Density functional theory calculations were carried out to understand the binding mechanism. The receptor was applied as a microbial sensor for Escherichia coli and Staphylococcus aureus.

  10. Impact of lymphoma treatments on spermatogenesis and sperm deoxyribonucleic acid: a multicenter prospective study from the CECOS network.

    Science.gov (United States)

    Bujan, Louis; Walschaerts, Marie; Brugnon, Florence; Daudin, Myriam; Berthaut, Isabelle; Auger, Jacques; Saias, Jacqueline; Szerman, Ethel; Moinard, Nathalie; Rives, Nathalie; Hennebicq, Sylvianne

    2014-09-01

    To determine consequences of lymphoma treatments on sperm characteristics and sperm DNA, and to evaluate predictors of sperm recovery. Multicenter prospective longitudinal study of patients analyzed before treatment and after 3, 6, 12, and 24 months. University hospitals. Seventy-five Hodgkin lymphoma and non-Hodgkin lymphoma patients and a control group of 257 fertile men. Semen analyses, and sperm DNA and chromatin assessments. Comparisons of sperm characteristics before and after treatment. Patients already had altered sperm characteristics before lymphoma treatment, with no identified risk factor. Sperm count, total sperm count, motility, and vitality decreased after treatment, with lowest values at 3 and 6 months. Twelve months after treatment, mean sperm count recovered to pretreatment values after doxorubicin, bleomycin, vinblastine, darcarbacine (ABVD) or ABVD+radiotherapy, but not after doxorubicin, cyclophosphamide, vincristine, prednisone (CHOP) or mechlorethamine, oncovin, procarbazine, prednisone (MOPP) chemotherapies. It was noteworthy that 7% of patients remained azoospermic at 24 months. After 24 months, Kaplan-Meier estimates showed that more than 90% of patients will recover normal sperm count after ABVD or ABVD+radiotherapy vs. 61% for CHOP chemotherapies. In multivariate analyses including diagnosis and treatment protocol, only pretreatment total sperm count was related to recovery. Compared with a control group, lymphoma patients had higher sperm chromatin alterations and DNA fragmentation before any treatment. After treatment, DNA fragmentation assessed by TUNEL assay and sperm chromatin structure assay decreased from 3 and 6 months, respectively, while remaining higher than in the control group during follow-up. Lymphoma patients had altered sperm DNA and chromatin before treatment. Lymphoma treatment had damaging effects on spermatogenesis. These data on both the recovery period according to treatment modalities and the pre- and post-treatment chromatin status of sperm are useful tools for counseling patients wishing to conceive. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Psoralen-deoxyribonucleic acid photoreaction. Characterization of the monoaddition products from 8-methoxypsoralen and 4,5',8-trimethylpsoralen

    International Nuclear Information System (INIS)

    Kanne, D.; Straub, K.; Rapoport, H.; Hearst, J.E.

    1982-01-01

    The isolation and structural characterization are described of the major monoaddition products formed in the photoreaction of two naturally occurring psoralens, 8-methoxypsoralen and 4,5',8-trimethylpsoralen, with high molecular weight, double-stranded DNA. Hydrolysis of the psoralen-modified DNA and subsequent chromatography resulted in the isolation of four modified nucleosides from each psoralen. Structural characterization was accomplished by mass spectrometry and 1 H NMR analysis. The major products, accounting for 44 to 52% of the covalently bound psoralen, are two diastereomeric thymidine adducts formed by cycloaddition between the 5,6 double bond of the pyrimidine and the 4',5' (furan) double bond of the psoralen. All of the isolated adducts have cis-syn stereochemistry. The stereochemistry and product distribution of the adducts are determined in part by the constraints imposed by the DNA helix on the geometry of the noncovalent intercalation complex formed by psoralen and DNA prior to irradiation

  12. Effects of polyamines and methylglyoxal bis(guanylhydrazone) on hepatic nuclear structure and deoxyribonucleic acid template activity.

    Science.gov (United States)

    Brown, K B; Nelson, N F; Brown, D G

    1975-12-01

    1. The interaction of polyamines and methylglyoxal bis(guanythydrazone) (1, 1'-[(methylethanediylidene)-dinitrilo]diguanidine) with isolated rat liver nuclei was investigated by electron microscopy. 2. At 4mM, putrescine was without effect; however, spermidine, spermine or methylglyoxal bis(guanythydrazone) resulted in dispersed chromatin and alterations in nucleolar structure. In addition, spermidine or methylglyoxal bis(guanylhydrazone) caused marked aggregation of interchromatin granules. 3. The DNA template property of calf thymus DNA was examined by using DNA polymerases from Escherichia coli, Micrococcus lysodeikticus and calf thymus in the presence of 0-5 mM-amine. 4. In the presence of DNA polymerase, spermine or methylglyoxal bis(guanylhydrazone) inhibited activity, whereas putrescine or spermidine had much less effect or in some cases stimulated [3H]dTMP incorporation. 5. Template activity which was inhibited by spermine or methylglyoxal bis(guanylhydrazone) could be partially restored by additional DNA or enzyme. 6. When mixed with calf thymus DNA, calf thymus histone inhibited template activity as measured with E. coli DNA polymerase. The template activity of such a 'histone-nucleate' could not be restored by putrescine, spermidine, spermine or methylglyoxal bis(guanylhydrazone). 7. DNA template activity of isolated rat liver nuclei was tested by using E. coli DNA polymerase. None of the amines was able to increase the template activity of the nuclear DNA in vitro.

  13. Anti-nucleosome antibodies in systemic lupus erythematosus patients: Relation to anti-double stranded deoxyribonucleic acid and disease activity

    Directory of Open Access Journals (Sweden)

    Mayada Ali Abdalla

    2018-01-01

    Conclusion: Anti-NCS antibodies could play a role in the pathogenesis of SLE and is related to disease activity. Its association with anti-dsDNA antibodies and its presence in those with negative anti-ds DNA may aid in the diagnosis of SLE.

  14. Binding of the water of primary hydration to the sodium and cesium salts of deoxyribonucleic acid and potassium hyaluronate

    Science.gov (United States)

    Whitson, K. B.; Lukan, A. M.; Marlowe, R. L.; Lee, S. A.; Anthony, L.; Rupprecht, A.

    1998-08-01

    Differential scanning calorimetry (DSC) has been used to evaluate the average enthalpy of desorption of the water of primary hydration bound to wet-spun films of potassium hyaluronate (KHA) and CsDNA. The enthalpies were measured to be 0.24+/-0.08 eV/H2O molecule for KHA and 0.32+/-0.10 eV/H2O molecule for CsDNA. A Kissinger analysis was used to extract the net activation energy (0.61+/-0.04 eV) for the desorption of this water from KHA by analyzing DSC data acquired at different heating rates. The average effective force constants at 295 K of this water bound to KHA (63+/-3 μdyn/Å) and NaDNA (17+/-4 μdyn/Å) are determined from Rayleigh scattering of Mossbauer radiation data [G. Albanese, A. Deriu, F. Cavatorta, and A. Rupprecht, Hyperfine Interact. 95, 97 (1995)] via a harmonic approximation.

  15. Inflammation but no DNA (deoxyribonucleic acid) damage in mice exposed to airborne dust from a biofuel plant

    DEFF Research Database (Denmark)

    Madsen, Anne Mette; Saber, Anne Thoustrup; Nordly, Pernille

    2008-01-01

    Objectives Particles in ambient air are associated with such health effects as lung diseases and cancer of the lung. Exposure to bioaerosols has been found to be associated with respiratory symptoms. The toxic properties of exposure to combustion and bioaerosol particles from biofuel plants have ...

  16. Semi-conservative deoxyribonucleic acid synthesis in unirradiated and ultraviolet-irradiated xeroderma pigmentosum and normal human skin fibroblasts

    International Nuclear Information System (INIS)

    Rude, J.M.; Friedberg, E.C.

    1977-01-01

    Rates of semiconservative DNA synthesis have been investigated in asynchronous xeroderma pigmentosum (XP), XP variant, and normal human skin fibroblasts using the technique of cellular autoradiography. In unirradiated cells, no differences in DNA synthesis rates were detected among the three cell strains. Exposure to UV radiation caused the rate of DNA synthesis to decrease for at least three hours in all three cell strains. In the normal cell strain, recovery of the DNA synthetic rate occurred at later times following a UV fluence of 5 J/m 2 . At this same UV fluence, recovery was absent in classical XP cells during a 24 h post-irradiation period while it was slower than normal in XP variant cells. When the UV fluence to classical XP and XP variant cells was reduced so that survival in all three cell strains was approximately the same (25%), recovery of the DNA synthetic rate was similar in all three cell strains. These results are discussed in terms of current models of DNA replication in UV-irradiated cells and indicate: (1) that pyrimidine dimers are very effective blocks to DNA synthesis and (2) that there is no inherent defect in semiconservative DNA synthesis in either classical XP or XP variant cells which is independent of a defect in DNA repair capacity

  17. Different reparability of the chromosomal and cytoplasmic deoxyribonucleic acid in Escherichia coli damaged by γ and ultraviolet irradiation

    International Nuclear Information System (INIS)

    Petranovic, D.; Petranovic, M.; Nozinic, R.; Trgovcevic, Z.

    1978-01-01

    The relative efficiencies by which chromosomal and extrachromosomal DNAs are repaired in irradiated bacteria were assayed. Repair-proficient Escherichia coli C600 cells lysogenic for, or infected with, the thermoinducible phage lambdacI857 ind were exposed to γ or uv radiation and then tested for colony- and plaque-forming ability. The results show that the bacterial cell is about 5 times more sensitive to γ rays and about 1.5 times more sensitive to uv light, if compared to either (1) the prophage that is irradiated in the bacterial chromosome and, on heat induction, repaired in the cytoplasm or (2) the infecting phage that is irradiated and repaired in the cytoplasm. Since the bacterial DNA is about 80 times larger than the phage DNA, it is inferred that repair processes operating along the chromosomal DNA are one order of magnitude more efficient than those operating along the extrachromosomal DNA. This conclusion is reinforced by the fact that the absence of repair in the system Escherichia coli AB2480 uvrA recA-lambdacI857 ind red gives the expected ratio of 80/1 for the uv sensitivity of cells and that of intracellular phage

  18. Semi-conservative deoxyribonucleic acid synthesis in unirradiated and ultraviolet-irradiated xeroderma pigmentosum and normal human skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Rude' e, J.M.; Friedberg, E.C.

    1977-03-01

    Rates of semiconservative DNA synthesis have been investigated in asynchronous xeroderma pigmentosum (XP), XP variant, and normal human skin fibroblasts using the technique of cellular autoradiography. In unirradiated cells, no differences in DNA synthesis rates were detected among the three cell strains. Exposure to uv radiation caused the rate of DNA synthesis to decrease for at least three hours in all three cell strains. In the normal cell strain, recovery of the DNA synthetic rate occurred at later times following a uv fluence of 5 J/m2. At this same uv fluence, recovery was absent in classical XP cells during a 24 h post-irradiation period while it was slower than normal in XP variant cells. When the uv fluence to classical XP and XP variant cells was reduced so that survival in all three cell strains was approximately the same (25%), recovery of the DNA synthetic rate was similar in all three cell strains. These results are discussed in terms of current models of DNA replication in uv-irradiated cells and indicate: (1) that pyrimidine dimers are very effective blocks to DNA synthesis and (2) that there is no inherent defect in semi-conservative DNA synthesis in either classical XP or XP variant cells which is independent of a defect in DNA repair capacity.

  19. Bio Organic-Semiconductor Field-Effect Transistor (BioFET) Based on Deoxyribonucleic Acid (DNA) Gate Dielectric

    Science.gov (United States)

    2010-03-31

    floating gate devices and metal-insulator-oxide-semiconductor (MIOS) devices. First attempts to use polarizable gate insulators in combination with...bulk of the semiconductor (ii) Due to the polarizable gate dielectric (iii) dipole polarization and (iv)electret effect due to mobile ions in the...characterization was carried out under an argon environment inside the glove box. An Agilent model E5273A with a two source-measurement unit instrument was

  20. Simulation model of converging-diverging (CD) nozzle to improve particle delivery system of deoxyribonucleic acid (DNA)

    Science.gov (United States)

    Sumarsono, Danardono A.; Ibrahim, Fera; Santoso, Satria P.; Sari, Gema P.

    2018-02-01

    Gene gun is a mechanical device which has been used to deliver DNA vaccine into the cells and tissues by increasing the uptake of DNA plasmid so it can generate a high immune response with less amount of DNA. Nozzle is an important part of the gene gun which used to accelerate DNA in particle form with a gas flow to reach adequate momentum to enter the epidermis of human skin and elicit immune response. We developed new designs of nozzle for gene gun to make DNA uptake more efficient in vaccination. We used Computational Fluid Dynamics (CFD) by Autodesk® Simulation 2015 to simulate static fluid pressure and velocity contour of supersonic wave and parametric distance to predict the accuracy of the new nozzle. The result showed that the nozzle could create a shockwave at the distance parametric to the object from 4 to 5 cm using fluid pressure varied between 0.8-1.2 MPa. This is indication a possibility that the DNA particle could penetrate under the mammalian skin. For the future research step, this new nozzle model could be considered for development the main component of the DNA delivery system in vaccination in vivo

  1. Concentration characteristics of VOCs and acids/bases in the gas phase and water-soluble ions in the particle phase at an electrical industry park during construction and mass production.

    Science.gov (United States)

    Tsai, Jiun H; Huang, Yao S; Shieh, Zhu X; Chiang, Hung L

    2011-01-01

    The electronics industry is a major business in the Central Taiwan Science Park (CTSP). Particulate samples and 11 water-soluble ionic species in the particulate phase were measured by ionic chromatography (IC). Additionally, acid and base gases were sampled by denuder absorption and analyzed by IC. Volatile organic compounds (VOCs) were collected in stainless-steel canisters four times daily and analyzed via gas chromatography/mass spectrometry. Ozone formation potential (OFP) was measured using maximum increment reactivity. In addition, airborne pollutants during (1) construction and (2) mass production were measured. Particulate matter concentration did not increase significantly near the optoelectronic plant during construction, but it was higher than during mass production. SO(2), HNO(2) and NH(3) were the dominant gases in the denuder absorption system. Nitrate, sulfate, and ammonium ions predominated both in PM(2.5) and PM(10-2.5); but calcium ion concentration was significantly higher in PM(10-2.5) samples during construction. Toluene, propane, isopentane, and n-butane may have come from vehicle exhaust. Construction equipment emitted high concentrations of ethylbenzene, m-xylene, p-xylene, o-xylene, 1,2,4-trimethylbenzene, and toluene. During mass production, methyl ethyl ketone), acetone and ethyl acetate were significantly higher than during construction, although there was continuous rain. The aromatic group constituted >50% of the VOC concentration totals and contributed >70% of OFP.

  2. Heterologous Expression of the Carrot Hsp17.7 gene Increased Growth, Cell Viability, and Protein Solubility in Transformed Yeast (Saccharomyces cerevisiae) under Heat, Cold, Acid, and Osmotic Stress Conditions.

    Science.gov (United States)

    Ko, Eunhye; Kim, Minhye; Park, Yunho; Ahn, Yeh-Jin

    2017-08-01

    In industrial fermentation of yeast (Saccharomyces cerevisiae), culture conditions are often modified from the optimal growth conditions of the cells to maintain large-scale cultures and/or to increase recombinant protein production. However, altered growth conditions can be stressful to yeast cells resulting in reduced cell growth and viability. In this study, a small heat shock protein gene from carrot (Daucus carota L.), Hsp17.7, was inserted into the yeast genome via homologous recombination to increase tolerance to stress conditions that can occur during industrial culture. A DNA construct, Translational elongation factor gene promoter-carrot Hsp17.7 gene-Phosphoribosyl-anthranilate isomerase gene (an auxotrophic marker), was generated by a series of PCRs and introduced into the chromosome IV of the yeast genome. Immunoblot analysis showed that carrot Hsp17.7 accumulated in the transformed yeast cell lines. Growth rates and cell viability of these cell lines were higher than control cell lines under heat, cold, acid, and hyperosmotic stress conditions. Soluble protein levels were higher in the transgenic cell lines than control cell lines under heat and cold conditions, suggesting the molecular chaperone function of the recombinant Hsp17.7. This study showed that a recombinant DNA construct containing a HSP gene from carrot was successfully expressed in yeast by homologous recombination and increased tolerances to abiotic stress conditions.

  3. Soluble protein isolated from low cost fish and fish wastes

    OpenAIRE

    Lekshmy Nair, A.; Gopakumar, K.

    1982-01-01

    The method of preparation, composition, amino acid content, protein efficiency ratio and areas of possible application of water soluble protein isolates from low cost fish and fish wastes are discussed in detail in this communication.

  4. Potent Antioxidative Activity of Lycopene: A Potential Role in Scavenging Hypochlorous Acid

    OpenAIRE

    Pennathur, Subramaniam; Maitra, Dhiman; Byun, Jaeman; Sliskovic, Inga; Abdulhamid, Ibrahim; Saed, Ghassan M.; Diamond, Michael P.; Abu-Soud, Husam M.

    2010-01-01

    Lycopene, a carotenoid found in tomatoes, is a proven anti-oxidant that may lower the risk of certain disorders including heart disease and cancer. Hypochlorous acid (HOCl) is an oxidant linked to tissue oxidation in cardiovascular disease and other inflammatory disorders through its ability to modify proteins, deoxyribonucleic acid, ribonucleic acid and lipids. Here we show that lycopene can function as a potent scavenger of HOCl at a wide range of concentrations that span various pathophysi...

  5. THE SOLUBILITY OF MILAS BAUXITE ORE IN SULPHURIC ACI

    Directory of Open Access Journals (Sweden)

    Mustafa GULFEN

    2001-06-01

    Full Text Available The effects of calcination conditions,sulphuric acid concentrations and dissolvingtemperature and period as parameters to thesolubility of the bauxite ore from Gobekdagı reservesin Mugla-Milas region were investigated. The bauxitesamples were calcined in different periods at differenttemperatures. Then the solubility of the calcinedbauxite samples in sulphuric acid solution wasexamined. Dissolving activation energy (Ea wascalculated using the optimum kinetics equation andthe results obtained from the solubility studiesexamined dissolving temperatures and periods

  6. Hydrogen solubility measurements of analyzed tall oil fractions and a solubility model

    International Nuclear Information System (INIS)

    Uusi-Kyyny, Petri; Pakkanen, Minna; Linnekoski, Juha; Alopaeus, Ville

    2017-01-01

    Highlights: • Hydrogen solubility was measured in four tall oil fractions between 373 and 597 K. • Continuous flow synthetic isothermal and isobaric method was used. • A Henry’s law model was developed for the distilled tall oil fractions. • The complex composition of the samples was analyzed and is presented. - Abstract: Knowledge of hydrogen solubility in tall oil fractions is important for designing hydrotreatment processes of these complex nonedible biobased materials. Unfortunately measurements of hydrogen solubility into these fractions are missing in the literature. This work reports hydrogen solubility measured in four tall oil fractions between 373 and 597 K and at pressures from 5 to 10 MPa. Three of the fractions were distilled tall oil fractions their resin acids contents are respectively 2, 20 and 23 in mass-%. Additionally one fraction was a crude tall oil (CTO) sample containing sterols as the main neutral fraction. Measurements were performed using a continuous flow synthetic isothermal and isobaric method based on the visual observation of the bubble point. Composition of the flow was changed step-wise for the bubble point composition determination. We assume that the tall oil fractions did not react during measurements, based on the composition analysis performed before and after the measurements. Additionally the densities of the fractions were measured at atmospheric pressure from 293.15 to 323.15 K. A Henry’s law model was developed for the distilled tall oil fractions describing the solubility with an absolute average deviation of 2.1%. Inputs of the solubility model are temperature, total pressure and the density of the oil at 323.15 K. The solubility of hydrogen in the CTO sample can be described with the developed model with an absolute average deviation of 3.4%. The solubility of hydrogen increases both with increasing pressure and/or increasing temperature. The more dense fractions of the tall oil exhibit lower hydrogen

  7. Soluble CD163

    DEFF Research Database (Denmark)

    Møller, Holger J

    2012-01-01

    CD163 is an endocytic receptor for haptoglobin-hemoglobin complexes and is expressed solely on macrophages and monocytes. As a result of ectodomain shedding, the extracellular portion of CD163 circulates in blood as a soluble protein (sCD163) at 0.7-3.9 mg/l in healthy individuals. The function o...

  8. Solubility Part 1

    NARCIS (Netherlands)

    Tantra, Ratna; Bolea, Eduardo; Bouwmeester, H.; Rey-Castro, Carlos; David, C.A.A.; Dogné, Jean Michel; Laborda, Francisco; Laloy, Julie; Robinson, Kenneth N.; Undas, A.K.; Zande, van der M.

    2016-01-01

    This chapter gives an overview of different methods that can potentially be used to determine the solubility of nanomaterials. In general, the methods presented can be broadly divided into four categories: separation methods, methods to quantify free ions, methods to quantify total dissolved

  9. Oxidative potential of ambient water-soluble PM2.5 in the southeastern United States: contrasts in sources and health associations between ascorbic acid (AA and dithiothreitol (DTT assays

    Directory of Open Access Journals (Sweden)

    T. Fang

    2016-03-01

    Full Text Available The ability of certain components of particulate matter to induce oxidative stress through the generation of reactive oxygen species (ROS in vivo may be one mechanism accounting for observed linkages between ambient aerosols and adverse health outcomes. A variety of assays have been used to measure this so-called aerosol oxidative potential. We developed a semi-automated system to quantify oxidative potential of filter aqueous extracts utilizing the dithiothreitol (DTT assay and report here the development of a similar semi-automated system for the ascorbic acid (AA assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed for a host of aerosol species, along with AA and DTT activities. We present a detailed contrast in findings from these two assays. Water-soluble AA activity was higher in summer and fall than in winter, with highest levels near heavily trafficked highways, whereas DTT activity was higher in winter compared to summer and fall and more spatially homogeneous. AA activity was nearly exclusively correlated with water-soluble Cu (r  =  0.70–0.94 at most sites, whereas DTT activity was correlated with organic and metal species. Source apportionment models, positive matrix factorization (PMF and a chemical mass balance method with ensemble-averaged source impact profiles (CMB-E, suggest a strong contribution from traffic emissions and secondary processes (e.g., organic aerosol oxidation or metals mobilization by secondary acids to both AA and DTT activities in urban Atlanta. In contrast, biomass burning was a large source for DTT activity, but insignificant for AA. AA activity was not correlated with PM2.5 mass, while DTT activity co-varied strongly with mass (r  =  0.49–0.86 across sites and seasons. Various linear models were developed to estimate AA and DTT activities for the central Atlanta Jefferson Street site, based on the CMB-E sources. The

  10. Injury-induced inhibition of small intestinal protein and nucleic acid synthesis

    International Nuclear Information System (INIS)

    Carter, E.A.; Hatz, R.A.; Yarmush, M.L.; Tompkins, R.G.

    1990-01-01

    Small intestinal mucosal weight and nutrient absorption are significantly diminished early after cutaneous thermal injuries. Because these intestinal properties are highly dependent on rates of nucleic acid and protein synthesis, in vivo incorporation of thymidine, uridine, and leucine into small intestinal deoxyribonucleic acid, ribonucleic acid, and proteins were measured. Deoxyribonucleic acid synthesis was markedly decreased with the lowest thymidine incorporation in the jejunum (p less than 0.01); these findings were confirmed by autoradiographic identification of radiolabeled nuclei in the intestinal crypts. Protein synthesis was decreased by 6 h postinjury (p less than 0.01) but had returned to normal by 48 h. Consistent with a decreased rate of protein synthesis, ribonucleic acid synthesis was also decreased 18 h postinjury (p less than 0.01). These decreased deoxyribonucleic acid, ribonucleic acid, and protein synthesis rates are not likely a result of ischemia because in other studies of this injury model, intestinal blood flow was not significantly changed by the burn injury. Potentially, factors initiating the acute inflammatory reaction may directly inhibit nucleic acid and protein synthesis and lead to alterations in nutrient absorption and intestinal barrier function after injury

  11. Molybdenum solubility in aluminium nitrate solutions

    Energy Technology Data Exchange (ETDEWEB)

    Heres, X.; Sans, D.; Bertrand, M.; Eysseric, C. [CEA, Centre de Marcoule, Nuclear Energy Division, DRCP, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Brackx, E.; Domenger, R.; Excoffier, E. [CEA, Centre de Marcoule, Nuclear Energy Division, DTEC, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Valery, J.F. [AREVA-NC, DOR/RDP, Paris - La Defense (France)

    2016-07-01

    For over 60 years, research reactors (RR or RTR for research testing reactors) have been used as neutron sources for research, radioisotope production ({sup 99}Mo/{sup 99m}Tc), nuclear medicine, materials characterization, etc... Currently, over 240 of these reactors are in operation in 56 countries. They are simpler than power reactors and operate at lower temperature (cooled to below 100 C. degrees). The fuel assemblies are typically plates or cylinders of uranium alloy and aluminium (U-Al) coated with pure aluminium. These fuels can be processed in AREVA La Hague plant after batch dissolution in concentrated nitric acid and mixing with UOX fuel streams. The aim of this study is to accurately measure the solubility of molybdenum in nitric acid solution containing high concentrations of aluminium. The higher the molybdenum solubility is, the more flexible reprocessing operations are, especially when the spent fuels contain high amounts of molybdenum. To be most representative of the dissolution process, uranium-molybdenum alloy and molybdenum metal powder were dissolved in solutions of aluminium nitrate at the nominal dissolution temperature. The experiments showed complete dissolution of metallic elements after 30 minutes long stirring, even if molybdenum metal was added in excess. After an induction period, a slow precipitation of molybdic acid occurs for about 15 hours. The data obtained show the molybdenum solubility decreases with increasing aluminium concentration. The solubility law follows an exponential relation around 40 g/L of aluminium with a high determination coefficient. Molybdenum solubility is not impacted by the presence of gadolinium, or by an increasing concentration of uranium. (authors)

  12. Development of solid lipid nanoparticles for enhanced solubility of poorly soluble drugs

    DEFF Research Database (Denmark)

    Potta, Sriharsha Gupta; Minemi, Sriharsha; Nukala, Ravi Kumar

    2010-01-01

    Cyclosporine (CyA) solid lipid nanoparticles were prepared by using a solvent free high pressure homogenization process. CyA was incorporated into SLNs that consisted of stearic acid, trilaurin or tripalmitin lipid solid cores in order to enhance drug solubility. The process was conducted...

  13. Thermodynamic approach to improving solubility prediction of co-crystals in comparison with individual poorly soluble components

    International Nuclear Information System (INIS)

    Perlovich, German L.

    2014-01-01

    Highlights: • Thermodynamic approach for solubility improvement of co-crystal was developed. • The graphical technique for estimation of co-crystal solubility was elaborated. • Hydration enthalpies of some drugs and amino acids were calculated. • Applicability/operability of the approach was exemplified by some drugs and amino acids. - Abstract: A novel thermodynamic approach to compare poorly soluble components (active pharmaceutical ingredient (API)) both in co-crystals and individual compounds was developed. An algorithm of choosing potential co-crystals with improved solubility characteristics on the basis of the known solvation/hydration API and co-former enthalpies is described. The applicability and operability of the algorithm were tested exemplified by some drugs and amino acids

  14. Effect of Thymine Starvation on Messenger Ribonucleic Acid Synthesis in Escherichia coli

    Science.gov (United States)

    Luzzati, Denise

    1966-01-01

    Luzzati, Denise (Institut de Biologie Physico-Chimique, Paris, France). Effect of thymine starvation on messenger ribonucleic acid synthesis in Escherichia coli. J. Bacteriol. 92:1435–1446. 1966.—During the course of thymine starvation, the rate of synthesis of messenger ribonucleic acid (mRNA, the rapidly labeled fraction of the RNA which decays in the presence of dinitrophenol or which hybridizes with deoxyribonucleic acid) decreases exponentially, in parallel with the viability of the thymine-starved bacteria. The ability of cell-free extracts of starved bacteria to incorporate ribonucleoside triphosphates into RNA was determined; it was found to be inferior to that of extracts from control cells. The analysis of the properties of cell-free extracts of starved cells shows that their decreased RNA polymerase activity is the consequence of a modification of their deoxyribonucleic acid, the ability of which to serve as a template for RNA polymerase decreases during starvation. PMID:5332402

  15. Measurement of Soluble Biomarkers by Flow Cytometry

    OpenAIRE

    Antal-Szalm?s, P?ter; Nagy, B?la; Debreceni, Ildik? Beke; Kappelmayer, J?nos

    2013-01-01

    Microparticle based flow cytometric assays for determination of the level of soluble biomarkers are widely used in several research applications and in some diagnostic setups. The major advantages of these multiplex systems are that they can measure a large number of analytes (up to 500) at the same time reducing assay time, costs and sample volume. Most of these assays are based on antigen-antibody interactions and work as traditional immunoassays, but nucleic acid alterations ? by using spe...

  16. Uranyl Oxalate Solubility

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G.; Costenoble, S.; Grandjean, S. [CEA Marcoule DEN/DRCP/SCPS/LCA - BP17171 - 30207 Bagnols sur Ceze cedex (France)

    2008-07-01

    The solubility of uranyl oxalate was determined at ambient temperature by precipitation in oxalic-nitric solutions, using an initial uranyl concentration of 0.1 mol/L. Oxalic concentration varied from 0.075 to 0.3 mol/L while nitric concentration ranged between 0.75 and 3 mol/L. Dissolution tests, using complementary oxalic-nitric media, were carried out for 550 hours in order to study the kinetic to reach thermodynamic equilibrium. Similar solubility values were reached by dissolution and precipitation. Using the results, it was possible to draw the solubility surface versus oxalic and nitric concentrations and to determine both the apparent solubility constant of UO{sub 2}C{sub 2}O{sub 4}, 3H{sub 2}O (Ks) and the apparent formation constant of the first uranyl-oxalate complex UO{sub 2}C{sub 2}O{sub 4} (log {beta}1), for ionic strengths varying between 1 and 3 mol/L. Ks and log {beta}1 values were found to vary from 1.9 10{sup -8} to 9.2 10{sup -9} and from 5.95 to 6.06, respectively, when ionic strength varied from 1 to 3 mol/L. A second model may fit our data obtained at an ionic strength of 3 mol/L suggesting as reported by Moskvin et al. (1959) that no complexes are formed for [H{sup +}] at 3 M. The Ks value would then be 1.3 10{sup -8}. (authors)

  17. Argon solubility in liquid steel

    NARCIS (Netherlands)

    Boom, R; Dankert, O; Van Veen, A; Kamperman, AA

    2000-01-01

    Experiments have been performed to establish the solubility of argon in liquid interstitial-free steel. The solubility appears to be lower than 0.1 at ppb, The results are in line with argon solubilities reported in the literature on liquid iron. Semiempirical theories and calculations based on the

  18. Plasma concentrations of water.soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    Context: Vitamins B1 (thiamine), B3 (niacin), B6 (pyridoxine), and C (ascorbic acid) are vital for energy, carbohydrate, lipid, and amino acid metabolism and in the regulation of the cellular redox state. Some studies have associated low levels of water.soluble vitamins with metabolic syndrome and its various components.

  19. Soluble Molecularly Imprinted Nanorods for Homogeneous Molecular Recognition

    Directory of Open Access Journals (Sweden)

    Rongning Liang

    2018-03-01

    Full Text Available Nowadays, it is still difficult for molecularly imprinted polymers (MIPs to achieve homogeneous recognition since they cannot be easily dissolved in organic or aqueous phase. To address this issue, soluble molecularly imprinted nanorods have been synthesized by using soluble polyaniline doped with a functionalized organic protonic acid as the polymer matrix. By employing 1-naphthoic acid as a model, the proposed imprinted nanorods exhibit an excellent solubility and good homogeneous recognition ability. The imprinting factor for the soluble imprinted nanoroads is 6.8. The equilibrium dissociation constant and the apparent maximum number of the proposed imprinted nanorods are 248.5 μM and 22.1 μmol/g, respectively. We believe that such imprinted nanorods may provide an appealing substitute for natural receptors in homogeneous recognition related fields.

  20. Soluble Molecularly Imprinted Nanorods for Homogeneous Molecular Recognition

    Science.gov (United States)

    Liang, Rongning; Wang, Tiantian; Zhang, Huan; Yao, Ruiqing; Qin, Wei

    2018-03-01

    Nowadays, it is still difficult for molecularly imprinted polymer (MIPs) to achieve homogeneous recognition since they cannot be easily dissolved in organic or aqueous phase. To address this issue, soluble molecularly imprinted nanorods have been synthesized by using soluble polyaniline doped with a functionalized organic protonic acid as the polymer matrix. By employing 1-naphthoic acid as a model, the proposed imprinted nanorods exhibit an excellent solubility and good homogeneous recognition ability. The imprinting factor for the soluble imprinted nanoroads is 6.8. The equilibrium dissociation constant and the apparent maximum number of the proposed imprinted nanorods are 248.5 μM and 22.1 μmol/g, respectively. We believe that such imprinted nanorods may provide an appealing substitute for natural receptors in homogeneous recognition related fields.

  1. Molecular Design of Soluble Biopolyimide with High Rigidity

    Directory of Open Access Journals (Sweden)

    Sumant Dwivedi

    2018-03-01

    Full Text Available New soluble biopolyimides were prepared from a diamine derived from an exotic amino acid (4-aminocinnamic acid with several kinds of tetracarboxylic dianhydride. The biopolyimide molecular structural flexibility was tailored by modifying the tetracarboxylic dianhydride moiety. The obtained polyimides were soluble in various solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, and even tetrahydrofuran. It was observed that the biopolyimide solubility was greatly dependent upon the structural flexibility (torsion energy. Flexible structure facilitated greater solubility. The synthesized biopolyimides were largely amorphous and had number-average molecular weight (Mn in the range (5–8 × 105. The glass transition temperatures (Tg of the polymers ranged from 259–294 °C. These polymers exhibited good thermal stability without significant weight loss up to 410 °C. The temperatures at 10% weight loss (Td10 for synthesized biopolyimide ranged from 375–397 °C.

  2. Soluble porphyrin polymers

    Science.gov (United States)

    Gust, Jr., John Devens; Liddell, Paul Anthony

    2015-07-07

    Porphyrin polymers of Structure 1, where n is an integer (e.g., 1, 2, 3, 4, 5, or greater) ##STR00001## are synthesized by the method shown in FIGS. 2A and 2B. The porphyrin polymers of Structure 1 are soluble in organic solvents such as 2-MeTHF and the like, and can be synthesized in bulk (i.e., in processes other than electropolymerization). These porphyrin polymers have long excited state lifetimes, making the material suitable as an organic semiconductor for organic electronic devices including transistors and memories, as well as solar cells, sensors, light-emitting devices, and other opto-electronic devices.

  3. Solubility of heavy metals added to MSW

    International Nuclear Information System (INIS)

    Lo, H.M.; Lin, K.C.; Liu, M.H.; Pai, T.Z.; Lin, C.Y.; Liu, W.F.; Fang, G.C.; Lu, C.; Chiang, C.F.; Wang, S.C.; Chen, P.H.; Chen, J.K.; Chiu, H.Y.; Wu, K.C.

    2009-01-01

    This paper aims to investigate the six heavy metal levels (Cd, Cr, Cu, Pb, Ni and Zn) in municipal solid waste (MSW) at different pHs. It intends to provide the baseline information of metals solubility in MSW co-disposed or co-digested with MSW incinerator ashes in landfill or anaerobic bioreactors or heavy metals contaminated in anaerobic digesters. One milliliter (equal to 1 mg) of each metal was added to the 100 ml MSW and the batch reactor test was carried out. The results showed that higher HNO 3 and NaOH were consumed at extreme pH of 1 and 13 compared to those from pH 2 to 11 due to the comparably higher buffer capacity. Pb was found to have the least soluble level, highest metal adsorption (%) and highest partitioning K d (l g -1 ) between pH 3 and 12. In contrast, Ni showed the highest soluble level, lowest metal adsorption (%) and lowest K d (l g -1 ) between pH 4 and 12. Except Ni and Cr, other four metals seemed to show the amphibious properties as comparative higher solubility was found in the acidic and basic conditions

  4. Solubility of heavy metals added to MSW

    Energy Technology Data Exchange (ETDEWEB)

    Lo, H.M. [Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 Gifong E. Road, Wufong, Taichung County 41349, Taiwan (China)], E-mail: hmlo@cyut.edu.tw; Lin, K.C. [Department of Occupational Safety and Health, Chung Shan Medical University, 110, Sec. 1, Jiangguo N. Rd., Taichung 402, Taiwan (China); Liu, M.H.; Pai, T.Z. [Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 Gifong E. Road, Wufong, Taichung County 41349, Taiwan (China); Lin, C.Y. [Department of Soil and Water Conservation, Chung Hsing University, 250 Kuokuang Road, Taichung 402, Taiwan (China); Liu, W.F. [Department of Electronical Engineering, Feng Chia University, 100 Wenhwa Road, Taichung 407, Taiwan (China); Fang, G.C. [Department of Environmental Engineering, Hungkuang University, 34 Chung-Chie Road, Sha Lu, Taichung 433, Taiwan (China); Lu, C. [Department of Environmental Engineering, Chung Hsing University, 250 Kuokuang Road, Taichung 402, Taiwan (China); Chiang, C.F. [Department of Health Risk Management, China Medical University, No. 91 Hsueh-Shih Road, Taichung 40402, Taiwan (China); Wang, S.C.; Chen, P.H.; Chen, J.K.; Chiu, H.Y.; Wu, K.C. [Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 Gifong E. Road, Wufong, Taichung County 41349, Taiwan (China)

    2009-01-15

    This paper aims to investigate the six heavy metal levels (Cd, Cr, Cu, Pb, Ni and Zn) in municipal solid waste (MSW) at different pHs. It intends to provide the baseline information of metals solubility in MSW co-disposed or co-digested with MSW incinerator ashes in landfill or anaerobic bioreactors or heavy metals contaminated in anaerobic digesters. One milliliter (equal to 1 mg) of each metal was added to the 100 ml MSW and the batch reactor test was carried out. The results showed that higher HNO{sub 3} and NaOH were consumed at extreme pH of 1 and 13 compared to those from pH 2 to 11 due to the comparably higher buffer capacity. Pb was found to have the least soluble level, highest metal adsorption (%) and highest partitioning K{sub d} (l g{sup -1}) between pH 3 and 12. In contrast, Ni showed the highest soluble level, lowest metal adsorption (%) and lowest K{sub d} (l g{sup -1}) between pH 4 and 12. Except Ni and Cr, other four metals seemed to show the amphibious properties as comparative higher solubility was found in the acidic and basic conditions.

  5. Micelles from lipid derivatives of water-soluble polymers as delivery systems for poorly soluble drugs.

    Science.gov (United States)

    Lukyanov, Anatoly N; Torchilin, Vladimir P

    2004-05-07

    Polymeric micelles have a whole set of unique characteristics, which make them very promising drug carriers, in particular, for poorly soluble drugs. Our review article focuses on micelles prepared from conjugates of water-soluble polymers, such as polyethylene glycol (PEG) or polyvinyl pyrrolidone (PVP), with phospholipids or long-chain fatty acids. The preparation of micelles from certain polymer-lipid conjugates and the loading of these micelles with various poorly soluble anticancer agents are discussed. The data on the characterization of micellar preparations in terms of their morphology, stability, longevity in circulation, and ability to spontaneously accumulate in experimental tumors via the enhanced permeability and retention (EPR) effect are presented. The review also considers the preparation of targeted immunomicelles with specific antibodies attached to their surface. Available in vivo results on the efficiency of anticancer drugs incorporated into plain micelles and immunomicelles in animal models are also discussed.

  6. Soluble mediators and the interaction of drugs in IBD

    DEFF Research Database (Denmark)

    Rask-Madsen, J

    1998-01-01

    and 5-aminosalicylic acid (5-ASA), inhibit raised concentrations of these interdependent soluble mediators of inflammation, which may amplify one another or have parallel effects. Future medical options for treatment of IBD aim at removing perpetuating antigens or inhibiting the entry of inflammatory......, which provides the clinical manifestations of IBD. Other important soluble mediators of inflammation include complement-derived and chemotactic peptides, specific adhesion molecules, neuropeptides and reactive metabolites of oxygen and nitrogen. Current established therapies, such as glucocorticoids...

  7. Water-soluble dietary fibers and cardiovascular disease.

    Science.gov (United States)

    Theuwissen, Elke; Mensink, Ronald P

    2008-05-23

    One well-established way to reduce the risk of developing cardiovascular disease (CVD) is to lower serum LDL cholesterol levels by reducing saturated fat intake. However, the importance of other dietary approaches, such as increasing the intake of water-soluble dietary fibers is increasingly recognized. Well-controlled intervention studies have now shown that four major water-soluble fiber types-beta-glucan, psyllium, pectin and guar gum-effectively lower serum LDL cholesterol concentrations, without affecting HDL cholesterol or triacylglycerol concentrations. It is estimated that for each additional gram of water-soluble fiber in the diet serum total and LDL cholesterol concentrations decrease by -0.028 mmol/L and -0.029 mmol/L, respectively. Despite large differences in molecular structure, no major differences existed between the different types of water-soluble fiber, suggesting a common underlying mechanism. In this respect, it is most likely that water-soluble fibers lower the (re)absorption of in particular bile acids. As a result hepatic conversion of cholesterol into bile acids increases, which will ultimately lead to increased LDL uptake by the liver. Additionally, epidemiological studies suggest that a diet high in water-soluble fiber is inversely associated with the risk of CVD. These findings underlie current dietary recommendations to increase water-soluble fiber intake.

  8. Studies in the solubility of Pu(III) oxalate

    Energy Technology Data Exchange (ETDEWEB)

    Hasilkar, S P; Khedekar, N B; Chander, K; Jadhav, V; Jain, H C [Bhabha Atomic Research Centre, Bombay (India). Fuel Reprocessing Div.

    1994-11-01

    Studies have been carried out on the solubility of Pu(III) oxalate by precipitation of Pu(III) oxalate from varying concentrations of HNO[sub 3]/HCl (0.5-2.0M) solutions and also by equilibrating freshly prepared Pu(III) oxalate with solutions containing varying concentrations of HNO[sub 3]/HCl, oxalic acid and ascorbic acid. Pu(III) solutions in HNO[sub 3] and HCl media were prepared by reduction of Pu(IV) with ascorbic acid. 0.01-0.10M ascorbic acid concentration in the aqueous solution was maintained as holding reductant. The solubility of Pu(III) oxalate was found to be a minimum in 0.5M-1M HNO[sub 3]/HCl solutions containing 0.05M ascorbic acid and 0.2M excess oxalic acid in the supernatant. (author) 6 refs.; 6 tabs.

  9. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  10. Biochemical synthesis of water soluble conducting polymers

    Science.gov (United States)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-05-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  11. Biochemical synthesis of water soluble conducting polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Ferdinando F., E-mail: Ferdinando-Bruno@uml.edu [US Army Natick Soldier Research, Development and Engineering Center, Natick, MA 01760 (United States); Bernabei, Manuele [ITAF, Test Flight Centre, Chemistry Dept. Pratica di Mare AFB, 00071 Pomezia (Rome), Italy (UE) (Italy)

    2016-05-18

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  12. Biochemical synthesis of water soluble conducting polymers

    International Nuclear Information System (INIS)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-01-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  13. Evaluation of soluble organic compounds generated by radiological degradation of asphalt

    International Nuclear Information System (INIS)

    Fukumoto, M.; Nishikawa, Y.; Kagawa, A.; Kawamura, K.

    2000-12-01

    The soluble organic compounds generated by radiological degradation of asphalt (γ ray) were confirmed as a part of influence of the bituminized waste degradation in the TRU waste repository. Especially, the influence of the nitrate was focused on. As a result, the concentration of the soluble organic compounds generated by radiological degradation of asphalt (10 MGy, γ ray which is correspond to absorbed dose of asphalt for 1,000,000 years) were lower (each formic acid: about 50 mg/dm 3 , acetic acid: about 30 mg/dm 3 and oxalic acid: about 2 mg/dm 3 ) than that of the formic acid, the acetic acid and the oxalic acid which Valcke et al. had shown (the influence of the organic at the solubility examination which uses Pu and Am). Moreover, the change in the concentration of TOC and the soluble organic compounds (formic acid, acetic acid and oxalic acid) is little under the existence of nitrate ion. That is, the formic acid and acetic acid which can be organic ligands were generated little by oxidative decomposition of asphalt in the process that nitrate ion becomes nitride ion by radiation. The influence of the soluble organic compounds by the radiological degradation of the asphalt (γ ray) on adsorption and solubility by the complexation of radionuclides in the performance assessment can be limited. (author)

  14. Measurement and correlation of solubility of carbon dioxide in triglycerides

    International Nuclear Information System (INIS)

    Howlader, Md Shamim; French, William Todd; Toghiani, Hossein; Hartenbower, Ben; Pearson, Larry; DuBien, Janice; Rai, Neeraj

    2017-01-01

    Graphical abstract: Comparison of experimental results with correlation for solubility of CO 2 in triglycerides as a function pressure at two different temperatures of 289.15 and 303.15 K, respectively. - Highlights: • New pressure drop gas apparatus was developed to determine the solubility of gases in liquids. • Solubility of CO 2 in triglycerides was measured at different temperatures and pressures. • Experimental solubility data were correlated using three thermodynamic models. • Enthalpy, entropy and Gibbs energy of dissolution for CO 2 -triglyceride were determined. - Abstract: A new pressure drop solubility gas apparatus was developed to determine the solubility of carbon dioxide in canola oil, a triglyceride consisting primarily of oleic, linoleic, and alpha linoleic acid radicals. Solubility of CO 2 in triglycerides was determined at different temperatures (283.2–303.2 K) and pressures (600–2450 kPa). It was found that the solubility of CO 2 in triglycerides is higher than that of pure water because triglycerides lack strong hydrogen bond networks that exist in liquid water at the ambient conditions. The experimental solubility was correlated using Krichevsky–Kasarnovsky (KK), Mather-Jou (MJ), and Carvalho-Coutinho (CC) correlations. We find that KK and MJ equations can predict the solubility with higher accuracy. The enthalpy and entropy of absorption of CO 2 were calculated using the van’t Hoff plot and were found to be −7.165 kJ.mol −1 , and −28.791 J.mol −1 .K −1 , respectively.

  15. pH-metric solubility. 3. Dissolution titration template method for solubility determination.

    Science.gov (United States)

    Avdeef, A; Berger, C M

    2001-12-01

    The main objective of this study was to develop an effective potentiometric saturation titration protocol for determining the aqueous intrinsic solubility and the solubility-pH profile of ionizable molecules, with the specific aim of overcoming incomplete dissolution conditions, while attempting to shorten the data collection time. A modern theory of dissolution kinetics (an extension of the Noyes-Whitney approach) was applied to acid-base titration experiments. A thermodynamic method was developed, based on a three-component model, to calculate interfacial, diffusion-layer, and bulk-water reactant concentrations in saturated solutions of ionizable compounds perturbed by additions of acid/base titrant, leading to partial dissolution of the solid material. Ten commercial drugs (cimetidine, diltiazem hydrochloride, enalapril maleate, metoprolol tartrate, nadolol, propoxyphene hydrochloride, quinine hydrochloride, terfenadine, trovafloxacin mesylate, and benzoic acid) were chosen to illustrate the new titration methodology. It was shown that the new method is about 10 times faster in determining equilibrium solubility constants, compared to the traditional saturation shake-flask methods.

  16. [Impacts of multicomponent environment on solubility of puerarin in biopharmaceutics classification system of Chinese materia medica].

    Science.gov (United States)

    Hou, Cheng-Bo; Wang, Guo-Peng; Zhang, Qiang; Yang, Wen-Ning; Lv, Bei-Ran; Wei, Li; Dong, Ling

    2014-12-01

    To illustrate the solubility involved in biopharmaceutics classification system of Chinese materia medica (CMMBCS) , the influences of artificial multicomponent environment on solubility were investigated in this study. Mathematical model was built to describe the variation trend of their influence on the solubility of puerarin. Carried out with progressive levels, single component environment: baicalin, berberine and glycyrrhizic acid; double-component environment: baicalin and glycyrrhizic acid, baicalin and berberine and glycyrrhizic acid and berberine; and treble-component environment: baicalin, berberin, glycyrrhizic acid were used to describe the variation tendency of their influences on the solubility of puerarin, respectively. And then, the mathematical regression equation model was established to characterize the solubility of puerarin under multicomponent environment.

  17. Students’ misconceptions on solubility equilibrium

    Science.gov (United States)

    Setiowati, H.; Utomo, S. B.; Ashadi

    2018-05-01

    This study investigated the students’ misconceptions of the solubility equilibrium. The participants of the study consisted of 164 students who were in the science class of second year high school. Instrument used is two-tier diagnostic test consisting of 15 items. Responses were marked and coded into four categories: understanding, misconception, understand little without misconception, and not understanding. Semi-structured interviews were carried out with 45 students according to their written responses which reflected different perspectives, to obtain a more elaborated source of data. Data collected from multiple methods were analyzed qualitatively and quantitatively. Based on the data analysis showed that the students misconceptions in all areas in solubility equilibrium. They had more misconceptions such as in the relation of solubility and solubility product, common-ion effect and pH in solubility, and precipitation concept.

  18. Solubility and dissolution improvement of ketoprofen by emulsification ionic gelation

    Science.gov (United States)

    Rachmaniar, Revika; Tristiyanti, Deby; Hamdani, Syarif; Afifah

    2018-02-01

    Ketoprofen or [2-(3-benzoylphenyl) propionic acid] is non-steroidal anti-inflammatory (NSAID) and an analgesic which has high permeability and low solubility. The purpose of this work was to improve the solubility and dissolution of poorly water-soluble ketoprofen prepared by emulsification ionic gelation method and utilizing polymer (chitosan) and cross linker (tripolyphosphate, TPP) for particles formulation. The results show that increasing pH value of TPP, higher solubility and dissolution of as-prepared ketoprofen-chitosan was obtained. The solubility in water of ketoprofen-chitosan with pH 6 for TPP increased 2.71-fold compared to untreated ketoprofen. While the dissolution of ketoprofen-chitosan with pH 6 of TPP in simulated gastric fluid without enzyme (0.1 N HCl), pH 4.5 buffer and simulated intestinal fluid without enzyme (phosphate buffer pH 6.8) was increased 1.9-fold, 1.6-fold and 1.2-fold compared to untreated ketoprofen for dissolution time of 30 minutes, respectively. It could be concluded that chitosan and TPP in the emulsification ionic gelation method for ketoprofen preparation effectively increases solubility and dissolution of poorly water-soluble ketoprofen.

  19. The solubility of palladium(II) bis-dimethylglyoximate

    International Nuclear Information System (INIS)

    Maghzian, R.

    1978-01-01

    The solubility of palladium(II) bis-dimethylglyoximate in different solutions has been determined. Values obtained for the solubility of the palladium complex are tabulated. The solubility is the lowest in water, ammonium acetate and a 25% acetone-water mixture. It is highest in dilute HCl and acetone but precipitation from aqueous acetone should be satisfactory for most purposes if the acetone content of the solvent is roughly less than 50% by volume. The solubility in dilute HCl reflects the concern by previous workers for losses in precipitation from mineral acid. In general, however, the losses are unlikely to be significant unless the quantity of palladium to be precipitated and weighed is small. (T.G.)

  20. Uranium solubility and solubility controls in selected Needle's Eye groundwaters

    International Nuclear Information System (INIS)

    Falck, W.E.; Hooker, P.J.

    1991-01-01

    The solubility control of uranium in selected groundwater samples from the cliff and sediments at the Needle's Eye natural analogue site is investigated using the speciation code PHREEQE and the CHEMVAL thermodynamic database (release 3). Alkali-earth bearing uranyl carbonate secondary minerals are likely to exert influence on the solubility . Other candidates are UO 2 and arsenates, depending on the prevailing redox conditions. In the absence of literature data, solubility products for important arsenates have been estimated from analogy with other arsenates and phosphates. Phosphates themselves are unlikely to exert control owing to their comparatively high solubilities. The influence of seawater flooding into the sediments is also discussed. The importance of uranyl arsenates in the retardation of uranium in shallow sediments has been demonstrated in theory, but there are some significant gaps in the thermodynamic databases used. (author)

  1. Noble gases solubility in water

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  2. [Fat soluble constituents of the leaves of Vaccinium bracteatum Thunb].

    Science.gov (United States)

    Tu, P; Liu, J; Li, J

    1997-07-01

    Four compounds were isolated from the fat soluble fraction of the leaves of Vaccinium bracteatum and identified as friedelin (I), epifriedelinol (II), beta-sitosterol(III) and ursolic acid(IV) by IR, NMR and MS. Compound III and IV are isolated from the leaves of this plant for the first time.

  3. Pure Phase Solubility Limits: LANL

    International Nuclear Information System (INIS)

    C. Stockman

    2001-01-01

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO 2 partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility products

  4. Pure Phase Solubility Limits: LANL

    Energy Technology Data Exchange (ETDEWEB)

    C. Stockman

    2001-01-26

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO{sub 2} partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility

  5. Aqueous solubility, dispersibility and toxicity of biodiesels

    International Nuclear Information System (INIS)

    Hollebone, B.P.; Fieldhouse, B.; Lumley, T.C.; Landriault, M.; Doe, K.; Jackman, P.

    2007-01-01

    The renewed interest in the use of biological fuels can be attributed to that fact that feedstocks for fatty-acid ester biodiesels are renewable and can be reclaimed from waste. Although there are significant benefits to using biodiesels, their increased use leaves potential for accidental release to the environment. Therefore, their environmental behaviours and impacts must be evaluated along with the risk associated with their use. Biodiesel fuels may be made from soy oil, canola oil, reclaimed restaurant grease, fish oil and animal fat. The toxicological fate of biofuel depends on the variability of its chemical composition. This study provided an initial assessment of the aqueous fate and effects of biodiesel from a broad range of commonly available feedstocks and their blends with petroleum diesels. The study focused primarily on the fate and impact of these fuels in fresh-water. The use of chemical dispersion as a countermeasure for saltwater was also investigated. The exposure of aquatic ecosystems to biodiesels and petroleum diesel occurs via the transfer of material from the non-aqueous phase liquid (NAPL) into the aqueous phase, as both soluble and dispersed components. The aqueous solubilities of the fuels were determined from the equilibrium water-accommodated fraction concentrations. The acute toxicities of many biodiesels were reported for 3 test species used by Environment Canada for toxicological evaluation, namely rainbow trout, the water flea and a luminescent bacterium. This study also evaluated the natural potential for dispersion of the fuels in the water column in both low and high-energy wave conditions. Chemical dispersion as a potential countermeasure for biodiesel spills was also evaluated using solubility testing, acute toxicity testing, and dispersibility testing. It was shown that biodiesels have much different fates and impacts from petroleum diesels. The compounds partitioning into the water column are also very different for each

  6. Iron solubility related to particle sulfur content in source emission and ambient fine particles.

    Science.gov (United States)

    Oakes, M; Ingall, E D; Lai, B; Shafer, M M; Hays, M D; Liu, Z G; Russell, A G; Weber, R J

    2012-06-19

    The chemical factors influencing iron solubility (soluble iron/total iron) were investigated in source emission (e.g., biomass burning, coal fly ash, mineral dust, and mobile exhaust) and ambient (Atlanta, GA) fine particles (PM2.5). Chemical properties (speciation and mixing state) of iron-containing particles were characterized using X-ray absorption near edge structure (XANES) spectroscopy and micro-X-ray fluorescence measurements. Bulk iron solubility (soluble iron/total iron) of the samples was quantified by leaching experiments. Major differences were observed in iron solubility in source emission samples, ranging from low solubility (iron solubility did not correspond to silicon content or Fe(II) content. However, source emission and ambient samples with high iron solubility corresponded to the sulfur content observed in single particles. A similar correspondence between bulk iron solubility and bulk sulfate content in a series of Atlanta PM2.5 fine particle samples (N = 358) further supported this trend. In addition, results of linear combination fitting experiments show the presence of iron sulfates in several high iron solubility source emission and ambient PM2.5 samples. These results suggest that the sulfate content (related to the presence of iron sulfates and/or acid-processing mechanisms by H(2)SO(4)) of iron-containing particles is an important proxy for iron solubility.

  7. Bioinspired co-crystals of Imatinib providing enhanced kinetic solubility.

    Science.gov (United States)

    Reggane, Maude; Wiest, Johannes; Saedtler, Marco; Harlacher, Cornelius; Gutmann, Marcus; Zottnick, Sven H; Piechon, Philippe; Dix, Ina; Müller-Buschbaum, Klaus; Holzgrabe, Ulrike; Meinel, Lorenz; Galli, Bruno

    2018-05-04

    Realizing the full potential of co-crystals enhanced kinetic solubility demands a comprehensive understanding of the mechanisms of dissolution, phase conversion, nucleation and crystal growth, and of the complex interplay between the active pharmaceutical ingredient (API), the coformer and co-existing forms in aqueous media. One blueprint provided by nature to keep poorly water-soluble bases in solution is the complexation with phenolic acids. Consequently, we followed a bioinspired strategy for the engineering of co-crystals of a poorly water-soluble molecule - Imatinib - with a phenolic acid, syringic acid (SYA). The dynamics of dissolution and solution-mediated phase transformations were monitored by Nuclear Magnetic Resonance (NMR) spectroscopy, providing mechanistic insights into the 60 fold-increased long lasting concentrations achieved by the syringate co-crystals as compared to Imatinib base and Imatinib mesylate. This lasting effect was linked to SYA's ability to delay the formation and nucleation of Imatinib hydrate - the thermodynamically stable form in aqueous media - through a metastable association of SYA with Imatinib in solution. Results from permeability studies evidenced that SYA did not impact Imatinib's permeability across membranes while suggesting improved bioavailability through higher kinetic solubility at the biological barriers. These results reflect that some degree of hydrophobicity of the coformer might be key to extend the kinetic solubility of co-crystals with hydrophobic APIs. Understanding how kinetic supersaturation can be shaped by the selection of an interactive coformer may help achieving the needed performance of new forms of poorly water-soluble, slowly dissolving APIs. Copyright © 2018. Published by Elsevier B.V.

  8. Solubility behavior of narcotic analgesics in aqueous media: solubilities and dissociation constants of morphine, fentanyl, and sufentanil.

    Science.gov (United States)

    Roy, S D; Flynn, G L

    1989-02-01

    The pH dependence of the aqueous solubility of morphine, fentanyl, and sufentanil was investigated at 35 degrees C. Dissociation constants and corresponding pKa' values of the drugs were obtained from measured free-base solubilities (determined at high pH's) and the concentrations of saturated solutions at intermediate pH's. Morphine, fentanyl, and sufentanil exhibited pKa' values of 8.08, 8.99, and 8.51, respectively. Over the pH range of 5 to 12.5 the apparent solubilities are determined by the intrinsic solubility of the free base plus the concentration of ionized drug necessary to satisfy the dissociation equilibrium at a given pH. Consequently, the drug concentrations of saturated aqueous solutions fall off precipitously as the pH is raised and ionization is suppressed. Further, at low pH's the aqueous solubility of morphine increased in a linear fashion with increases in the molar strength of citric acid which was added to acidify the medium, suggesting the formation of a soluble morphine-citrate complex.

  9. Characterization of Soluble Organics in Produced Water

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, D.T.

    2002-01-16

    -selective electrodes and inductively coupled plasma (ICP)-atomic emission spectrometry (AES). The WSO found in produced water samples was primarily polar in nature and distributed between the low and midrange carbon ranges. Typical levels of total extractable material (TEM) was about 20 mg/L; that associated with the aromatic fraction was present at 0.2 mg/L and that in the saturated hydrocarbon fraction was present at less than 0.02 mg/L. Formic, acetic, and propionic acids were also found in the produced water, occurring at a total concentration of 30 mg/L. It was estimated that the presence of 30 mg/L organic acids would artificially overstate TEM content by 2 mg/L. Of the five tested parameters, the factor that most controlled the total WSO in produced water was that of aqueous phase pH. Beyond a value of pH7 significant quantities of C{sub 10}-C{sub 20} range material become markedly soluble as they deprotonate in a basic aqueous phase. Both the absolute and relative volumes of GOM brine and crude additionally affected total WSO. Produced water appeared to reach a saturation level of WSO at a.50% water/oil ratio. Pressure slightly enhanced WSO by increasing the relative quantity of C{sub 6}-C{sub 10} range material. Temperature primarily altered the relative ratio of carbon ranges within the WSO without significantly elevating the total WSO in the GOM brine. Salinity had the least affect on the chemical character or the carbon size of WSO in produced water.

  10. On nitrogen solubility in water

    International Nuclear Information System (INIS)

    Kalajda, Yu.A.; Katkov, Yu.D.; Kuznetsov, V.A.; Lastovtsev, A.Yu.; Lastochkin, A.P.; Susoev, V.S.

    1980-01-01

    Presented are the results of experimental investigations on nitrogen solubility in water under 0-15 MPa pressure, at the temperature of 100-340 deg C and nitrogen concentration of 0-5000 n.ml. N 2 /kg H 2 O. Empiric equations are derived and a diagram of nitrogen solubility in water is developed on the basis of the experimental data, as well as critically evaluated published data. The investigation results can be used in analyzing water-gas regime of a primary heat carrier in stream-generating plants with water-water reactors

  11. Preliminary considerations concerning actinide solubilities

    International Nuclear Information System (INIS)

    Newton, T.W.; Bayhurst, B.P.; Daniels, W.R.; Erdal, B.R.; Ogard, A.E.

    1980-01-01

    Work at the Los Alamos Scientific Laboratory on the fundamental solution chemistry of the actinides has thus far been confined to preliminary considerations of the problems involved in developing an understanding of the precipitation and dissolution behavior of actinide compounds under environmental conditions. Attempts have been made to calculate solubility as a function of Eh and pH using the appropriate thermodynamic data; results have been presented in terms of contour maps showing lines of constant solubility as a function of Eh and pH. Possible methods of control of the redox potential of rock-groundwater systems by the use of Eh buffers (redox couples) is presented

  12. Thorium oxalate solubility and morphology

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.; Hall, R.

    1981-10-01

    Thorium was used as a stand-in for studying the solubility and precipitation of neptunium and plutonium oxalates. Thorium oxalate solubility was determined over a range of 0.001 to 10.0 in the concentration parameter [H 2 C 2 O 4 ]/[HNO 3 ] 2 . Morphology of thorium oxide made from the oxalate precipitates was characterized by scanning electron microscopy. The different morphologies found for oxalate-lean and oxalate-rich precipitations were in agreement with predictions based on precipitation theory

  13. Solubility database for TILA-99

    Energy Technology Data Exchange (ETDEWEB)

    Vuorinen, U.; Carlsson, T. [VTT Chemical Technology, Espoo (Finland); Kulmala, S.; Hakanen, M. [Helsinki Univ. (Finland). Lab. of Radiochemistry; Ahonen, L. [Geological Survey of Finland, Espoo (Finland)

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water ({approx}70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites

  14. Solubility database for TILA-99

    International Nuclear Information System (INIS)

    Vuorinen, U.; Carlsson, T.; Kulmala, S.; Hakanen, M.

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water (∼70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites. The

  15. Bismuth solubility through binding by various organic compounds and naturally occurring soil organic matter.

    Science.gov (United States)

    Murata, Tomoyoshi

    2010-01-01

    The present study was performed to examine the effects of soluble organic matter and pH on the solubility of Bi in relation to inference with the behavior of metallic Bi dispersed in soil and water environments using EDTA, citric acid, tartaric acid, L-cysteine, soil humic acids (HA), and dissolved organic matter (DOM) derived from the soil organic horizon. The solubility of Bi by citric acid, tartaric acid, L-cysteine, HA, and DOM showed pH dependence, while that by EDTA did not. Bi solubility by HA seemed to be related to the distribution of pKa (acid dissociation constant) values of acidic functional groups in their molecules. That is, HA extracted at pH 3.2 solubilized Bi preferentially in the acidic range, while HA extracted at pH 8.4 showed preferential solubilization at neutral and alkaline pH. This was related to the dissociation characteristics of functional groups, their binding capacity with Bi, and precipitation of Bi carbonate or hydroxides. In addition to the dissociation characteristics of functional groups, the unique structural configuration of the HA could also contribute to Bi-HA complex formation. The solubility of Bi by naturally occurring DOM derived from the soil organic horizon (Oi) and its pH dependence were different from those associated with HA and varied among tree species.

  16. Solubility of Plutonium (IV) Oxalate During Americium/Curium Pretreatment

    International Nuclear Information System (INIS)

    Rudisill, T.S.

    1999-01-01

    Approximately 15,000 L of solution containing isotopes of americium and curium (Am/Cm) will undergo stabilization by vitrification at the Savannah River Site (SRS). Prior to vitrification, an in-tank pretreatment will be used to remove metal impurities from the solution using an oxalate precipitation process. Material balance calculations for this process, based on solubility data in pure nitric acid, predict approximately 80 percent of the plutonium in the solution will be lost to waste. Due to the uncertainty associated with the plutonium losses during processing, solubility experiments were performed to measure the recovery of plutonium during pretreatment and a subsequent precipitation process to prepare a slurry feed for a batch melter. A good estimate of the plutonium content of the glass is required for planning the shipment of the vitrified Am/Cm product to Oak Ridge National Laboratory (ORNL).The plutonium solubility in the oxalate precipitation supernate during pretreatment was 10 mg/mL at 35 degrees C. In two subsequent washes with a 0.25M oxalic acid/0.5M nitric acid solution, the solubility dropped to less than 5 mg/mL. During the precipitation and washing steps, lanthanide fission products in the solution were mostly insoluble. Uranium, and alkali, alkaline earth, and transition metal impurities were soluble as expected. An elemental material balance for plutonium showed that greater than 94 percent of the plutonium was recovered in the dissolved precipitate. The recovery of the lanthanide elements was generally 94 percent or higher except for the more soluble lanthanum. The recovery of soluble metal impurities from the precipitate slurry ranged from 15 to 22 percent. Theoretically, 16 percent of the soluble oxalates should have been present in the dissolved slurry based on the dilution effects and volumes of supernate and wash solutions removed. A trace level material balance showed greater than 97 percent recovery of americium-241 (from the beta dec

  17. Concomitant intake of alcohol may increase the absorption of poorly soluble drugs.

    Science.gov (United States)

    Fagerberg, Jonas H; Sjögren, Erik; Bergström, Christel A S

    2015-01-25

    Ethanol can increase the solubility of poorly soluble and hence present a higher drug concentration in the gastrointestinal tract. This may produce a faster and more effective absorption resulting in variable and/or high drug plasma concentrations, both of which can lead to adverse drug reactions. In this work we therefore studied the solubility and absorption effects of nine diverse compounds when ethanol was present. The apparent solubility was measured using the μDiss Profiler Plus (pION, MA) in four media representing gastric conditions with and without ethanol. The solubility results were combined with in-house data on solubility in intestinal fluids (with and without ethanol) and pharmacokinetic parameters extracted from the literature and used as input in compartmental absorption simulations using the software GI-Sim. Apparent solubility increased more than 7-fold for non-ionized compounds in simulated gastric fluid containing 20% ethanol. Compounds with weak base functions (cinnarizine, dipyridamole and terfenadine) were completely ionized at the studied gastric pH and their solubility was therefore unaffected by ethanol. Compounds with low solubility in intestinal media and a pronounced solubility increase due to ethanol in the upper gastric compartments showed an increased absorption in the simulations. The rate of absorption of the acidic compounds indomethacin and indoprofen was slightly increased but the extent of absorption was unaffected as the complete doses were readily absorbed even without ethanol. This was likely due to a high apparent solubility in the intestinal compartment where the weak acids are ionized. The absorption of the studied non-ionizable compounds increased when ethanol was present in the gastric and intestinal media. These results indicate that concomitant intake of alcohol may significantly increase the solubility and hence, the plasma concentration for non-ionizable, lipophilic compounds with the potential of adverse drug

  18. Solubility limits on radionuclide dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  19. Solubility of Nd in brine

    International Nuclear Information System (INIS)

    Khalili, F.I.; Symeopoulos, V.; Chen, J.F.; Choppin, G.R.

    1994-01-01

    The solubility of Nd(III) has been measured at 23±3 C in a synthetic brine at pcH 6.4, 8.4, 10.4 and 12.4. The brine consisted predominantly of (Na+K)Cl and MgCl 2 with an ionic strength of 7.8 M (9.4 m) a solid compound of Nd(III) at each pcH was assigned from X-ray diffraction patterns. The log values of the experimental solubilities decrease fomr -3 at pcH 6.4 to -5.8 at pcH 8.4; at pcH 10.4 and 12.4 the solubility was below the detection limit of -7.5. The experimental solubility does not follow closely the variation with pcH estimated from modeling of the species in solution in equilibrium with the Nd solid using S.I.T. (orig.)

  20. Nutritional composition and solubility of edible bird nest (Aerodramus fuchiphagus)

    Science.gov (United States)

    Halimi, Nurfatin Mohd; Kasim, Zalifah Mohd; Babji, Abdul Salam

    2014-09-01

    Edible bird nest (EBN) produced by certain swiftlet species mainly, Aerodromus fuciphagus. The objectives of this study were to determine and compare the proximate and amino acid composition of EBN obtained from two regions in Peninsular Malaysia (Pahang-A & Terengganu-B). The solubility of edible bird nest with varying pH, temperature and time was also investigated in this study. The results showed that, the EBN contained crude protein accounted to 58.55% (A) and 55.48% (B), carbohydrate at22.28% (A) & 25.79% (B), moisture content 15.90% (A) & 15.87% (B), fat, 0.67% (A) & and 0.29% (B) and ash contents 2.60% (A) & 2.57% (B) respectively. The major amino acids found in edible bird nest EBN were Glutamic acid (9.61%), Aspartic acid (6.34%), Lysine (5.44 %) and also Leucine (5.30%). The total solubility of EBN was also found to be increased when the temperature was increased increase with distilled water yielding the highest total solubility of EBN compared to others buffer (different pH) solutions.

  1. Production of a highly active, soluble form of the cytochrome P450 reductase (CPR A) from Candida tropicalis

    Science.gov (United States)

    Donnelly, Mark

    2006-08-01

    The present invention provides soluble cytochrome p450 reductase (CPR) proteins from Candida sp. having an altered N-terminal region which results in reduced hydrophobicity of the N-terminal region. Also provided are host cells comprising the subject soluble CPR proteins. In addition, the present invention provides nucleotide and corresponding amino acid sequences for soluble CPR proteins and vectors comprising the nucleotide sequences. Methods for producing a soluble CPR, for increasing production of a dicarboxylic acid, and for detecting a cytochrome P450 are also provided.

  2. The physicochemical properties and solubility of pharmaceuticals – Methyl xanthines

    International Nuclear Information System (INIS)

    Pobudkowska, Aneta; Domańska, Urszula; Kryska, Justyna A.

    2014-01-01

    the decomposition of Ph at high temperature. The important property tested was the constant acidity, to this end, the spectrophotometric method of Bates–Schwarzenbach was used. Unfortunately, with this method it was not possible to determine the value of pK a 7-(β-hydroxyethyl) theophylline. For other Phs, these values do not differ significantly from those proposed in the literature. Both awareness and knowledge of values of the drug pK a and solubility are important in Phs production. This allows the selection of a suitable solvent and allows estimation of the correct dose and its capacity to absorb in human body

  3. Solubility of simulated PWR primary circuit corrosion products

    International Nuclear Information System (INIS)

    Kunig, R.H.; Sandler, Y.L.

    1986-08-01

    The solubility behavior of non-stoichiometric nickel ferrites, nickel-cobalt ferrites, and magnetite, as model substances for the corrosion products (''crud'') formed in nuclear pressurized water reactors, was studied in a flow system in aqueous solutions of lithium hydroxide, boric acid, and hydrogen with pH, temperature, and hydrogen concentrations as parameters. Below the temperature region of 300 to 330 0 C, at hydrogen concentrations of 25 to 40 cm 3 /kg H 2 O as used during reactor operation, the solubility of nickel-cobalt ferrite is the same as that of Ni and Co/sub x/Fe/sub 3-x/O 4 (x 3 /kg of hydrogen, the equilibrium iron and nickel solubilities increase congruently down to about 100 0 C, in a manner consistent with the solubility of Fe 3 O 4 , but sharply decline at lower temperatures, apparently due to formation of a borated layer. A cooldown experiment on a time scale of a typical Westinghouse reactor shutdown, as well as static experiments carried out on various ferrite samples at 60 0 C show that after addition of oxygen or peroxide evolution of nickel (and possibly cobalt) above the equilibrium solubility in hydrogen depends on the presence of dissociation products prior to oxidation. Thermodynamic calculations of various reduction and oxidative decomposition reactions for stoichiometric and non-stoichiometric nickel ferrite and cobalt ferrite are presented. Their significance to evolutions of nickel and cobalt on reactor shutdown is discussed. 30 refs., 38 figs., 34 tabs

  4. Peptide Nucleic Acids

    DEFF Research Database (Denmark)

    2004-01-01

    A novel class of compounds known as peptide nucleic acids, bind complementary DNA and RNA strands, and generally do so more strongly than the corresponding DNA or RNA strands while exhibiting increased sequence specificity and solubility. The peptide nucleic acids comprise ligands selected from...

  5. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    Science.gov (United States)

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory.

  6. pH-potentiometric determination of solubility of barely soluble organic extracting agents in water and aqueous solutions of neutral salts

    International Nuclear Information System (INIS)

    Pavlovskaya, E.M.; Charykov, A.K.; Tikhomirov, V.I.

    1977-01-01

    A pH-potentiometric method has been used to estimate the solubility of chloroform, benzene and nitrobenzene in water. The desalting effect is studied of alkali metal chlorides on chloroform solubility to establish the following phenomenological series of alkali metal cations by their desalting action: Li + + + + + . The non-conformity of chloroform solubility values in water-isoactive solutions of different salts is indicative of the high specificity of desalting processes with respect to the chemical nature of the desalting cation. Salt effects also essentially depend on the chemical nature of the desalted substance, particularly on its acid-base properties

  7. Metronomic Adjuvant Chemotherapy Improves Treatment Outcome in Nasopharyngeal Carcinoma Patients With Postradiation Persistently Detectable Plasma Epstein-Barr Virus Deoxyribonucleic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Twu, Chih-Wen [Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Otorhinolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Wang, Wen-Yi [Section of Basic Medicine, Department of Nursing, Hung Kuang University, Taichung, Taiwan (China); Chen, Chien-Chih [Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Liang, Kai-Li; Jiang, Rong-San [Department of Otorhinolaryngology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Wu, Ching-Te [Department of Radiation Oncology, Taichung Veterans General Hospital–Chiayi Branch, Chiayi, Taiwan (China); Shih, Yi-Ting [Department of Radiation Oncology, St. Martin De Porres Hospital, Chiayi, Taiwan (China); Lin, Po-Ju; Liu, Yi-Chun [Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Lin, Jin-Ching, E-mail: jclin@vghtc.gov.tw [Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Radiation Oncology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine, China Medical University, Taichung, Taiwan (China)

    2014-05-01

    Purpose: To investigate the effects of adjuvant chemotherapy in nasopharyngeal carcinoma (NPC) patients with persistently detectable plasma Epstein-Barr virus DNA (pEBV DNA) after curative radiation therapy plus induction/concurrent chemotherapy. Methods and Materials: The study population consisted of 625 NPC patients with available pEBV DNA levels before and after treatment. Eighty-five patients with persistently detectable pEBV DNA after 1 week of completing radiation therapy were eligible for this retrospective study. Of the 85 patients, 33 were administered adjuvant chemotherapy consisting of oral tegafur-uracil (2 capsules twice daily) for 12 months with (n=4) or without (n=29) preceding intravenous chemotherapy of mitomycin-C, epirubicin, and cisplatin. The remaining 52 patients who did not receive adjuvant chemotherapy served as the control group. Results: Baseline patient characteristics at diagnosis (age, sex, pathologic type, performance status, T classification, N classification, and overall stage), as well as previous treatment modality, were comparable in both arms. After a median follow-up of 70 months for surviving patients, 45.5% (15 of 33 patients) with adjuvant chemotherapy and 71.2% (37 of 52 patients) without adjuvant chemotherapy experienced tumor relapses (P=.0323). There were a significant reduction in distant failure (P=.0034) but not in local or regional recurrence. The 5-year overall survival rate was 71.6% for patients with adjuvant chemotherapy and 28.7% for patients without adjuvant chemotherapy (hazard ratio 0.27; 95% confidence interval 0.17-0.55; P<.0001). Conclusions: Our retrospective data showed that adjuvant chemotherapy can reduce distant failure and improve overall survival in NPC patients with persistently detectable pEBV DNA after curative radiation therapy plus induction/concurrent chemotherapy.

  8. Analysis of three variable number terminal repeat loci is sufficient to characterize the deoxyribonucleic acid fingerprints of a panel of human tumor cell lines.

    Science.gov (United States)

    Anding, Allyson L; Reiss, Tanika; Germain, Glen S

    2003-01-01

    Using primers for the MCT118, YNZ22, and COL2A1 loci in polymerase chain reaction analysis we could distinguish among the approximately 20 cell lines routinely maintained in our laboratory. We also demonstrated that the cell line NB-1691 (a neuroblastoma) and its xenograft had an identical number of repeats at two loci. Rh30 (a rhabdomyosarcoma) made resistant to rapamycin was identical to its parent line and to a subline that had reverted to sensitivity after it was cultured without rapamycin in the medium.

  9. Deoxyribonucleic acid telomere length shortening can predict the incidence of non-alcoholic fatty liver disease in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Ping, Fan; Li, Zeng-Yi; Lv, Ke; Zhou, Mei-Cen; Dong, Ya-Xiu; Sun, Qi; Li, Yu-Xiu

    2017-03-01

    To investigate the effect of telomere shortening and other predictive factors of non-alcoholic fatty liver disease (NAFLD) in type 2 diabetes mellitus patients in a 6-year prospective cohort study. A total of 70 type 2 diabetes mellitus (mean age 57.8 ± 6.7 years) patients without NAFLD were included in the study, and 64 of them were successfully followed up 6 years later, excluding four cases with significant alcohol consumption. NAFLD was diagnosed by the hepatorenal ratio obtained by a quantitative ultrasound method using NIH image analysis software. The 39 individuals that developed NAFLD were allocated to group A, and the 21 individuals that did not develop NAFLD were allocated to group B. Fluorescent real-time quantitative polymerase chain reaction was used to measure telomere length. There was no significant difference between the two groups in baseline telomere length; however, at the end of the 6th year, telomere length had become shorter in group A compared with group B. There were significant differences between these two groups in baseline body mass index, waistline, systolic blood pressure, glycated hemoglobin and fasting C-peptide level. In addition, the estimated indices of baseline insulin resistance increased in group A. Fasting insulin level, body mass index, systolic blood pressure at baseline and the shortening of telomere length were independent risk factors of NAFLD in type 2 diabetes mellitus patients. Telomere length became shorter in type 2 diabetes mellitus patients who developed NAFLD over the course of 6 years. Type 2 diabetes mellitus patients who developed NAFLD had more serious insulin resistance compared with those who did not develop NAFLD a long time ago. © 2016 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  10. Alkylation of deoxyribonucleic acid by carcinogens dimethyl sulphate, ethyl methanesulphonate, N-ethyl-N-nitrosourea and N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Swenson, D.H.; Lawley, P.D.

    1978-01-01

    The ethyl phosphotriester of thymidylyl(3'-5')thymidine, dTp((Et) dT, was identified as a product from the reaction of DNA with N-ethyl-N-nitrosourea. Enzymic degradation to yield alkyl phosphotriesters from DNA alkylated by this carcinogen, and by N-methyl-N-nitrosourea, dimethyl sulphate and ethyl methanesulphonate was studied quantitatively, and the relative yields of the triesters dTp(Alk)dT were determined. The relative reactivity of the phosphodiester group dTpdT to each of the four carcinogens was thus obtained, and compared with that of DNA overall, or with that of the N-7 atom of guanine in DNA. The results are related to steric factors, and the electrophilic character of each carcinogen. (author)

  11. Binding of the biogenic polyamines to deoxyribonucleic acids of varying base composition: base specificity and the associated energetics of the interaction.

    Directory of Open Access Journals (Sweden)

    Ayesha Kabir

    Full Text Available BACKGROUND: The thermodynamics of the base pair specificity of the binding of the polyamines spermine, spermidine, putrescine, and cadaverine with three genomic DNAs Clostridium perfringens, 27% GC, Escherichia coli, 50% GC and Micrococcus lysodeikticus, 72% GC have been studied using titration calorimetry and the data supplemented with melting studies, ethidium displacement and circular dichroism spectroscopy results. METHODOLOGY/PRINCIPAL FINDINGS: Isothermal titration calorimetry, differential scanning calorimetry, optical melting studies, ethidium displacement, circular dichroism spectroscopy are the various techniques employed to characterize the interaction of four polyamines, spermine, spermidine, putersine and cadaverine with the DNAs. Polyamines bound stronger with AT rich DNA compared to the GC rich DNA and the binding varied depending on the charge on the polyamine as spermine>spermidine >putrescine>cadaverine. Thermodynamics of the interaction revealed that the binding was entropy driven with small enthalpy contribution. The binding was influenced by salt concentration suggesting the contribution from electrostatic forces to the Gibbs energy of binding to be the dominant contributor. Each system studied exhibited enthalpy-entropy compensation. The negative heat capacity changes suggested a role for hydrophobic interactions which may arise due to the non polar interactions between DNA and polyamines. CONCLUSION/SIGNIFICANCE: From a thermodynamic analysis, the AT base specificity of polyamines to DNAs has been elucidated for the first time and supplemented by structural studies.

  12. Binding of the biogenic polyamines to deoxyribonucleic acids of varying base composition: base specificity and the associated energetics of the interaction.

    Science.gov (United States)

    Kabir, Ayesha; Suresh Kumar, Gopinatha

    2013-01-01

    The thermodynamics of the base pair specificity of the binding of the polyamines spermine, spermidine, putrescine, and cadaverine with three genomic DNAs Clostridium perfringens, 27% GC, Escherichia coli, 50% GC and Micrococcus lysodeikticus, 72% GC have been studied using titration calorimetry and the data supplemented with melting studies, ethidium displacement and circular dichroism spectroscopy results. Isothermal titration calorimetry, differential scanning calorimetry, optical melting studies, ethidium displacement, circular dichroism spectroscopy are the various techniques employed to characterize the interaction of four polyamines, spermine, spermidine, putersine and cadaverine with the DNAs. Polyamines bound stronger with AT rich DNA compared to the GC rich DNA and the binding varied depending on the charge on the polyamine as spermine>spermidine >putrescine>cadaverine. Thermodynamics of the interaction revealed that the binding was entropy driven with small enthalpy contribution. The binding was influenced by salt concentration suggesting the contribution from electrostatic forces to the Gibbs energy of binding to be the dominant contributor. Each system studied exhibited enthalpy-entropy compensation. The negative heat capacity changes suggested a role for hydrophobic interactions which may arise due to the non polar interactions between DNA and polyamines. From a thermodynamic analysis, the AT base specificity of polyamines to DNAs has been elucidated for the first time and supplemented by structural studies.

  13. Metronomic Adjuvant Chemotherapy Improves Treatment Outcome in Nasopharyngeal Carcinoma Patients With Postradiation Persistently Detectable Plasma Epstein-Barr Virus Deoxyribonucleic Acid

    International Nuclear Information System (INIS)

    Twu, Chih-Wen; Wang, Wen-Yi; Chen, Chien-Chih; Liang, Kai-Li; Jiang, Rong-San; Wu, Ching-Te; Shih, Yi-Ting; Lin, Po-Ju; Liu, Yi-Chun; Lin, Jin-Ching

    2014-01-01

    Purpose: To investigate the effects of adjuvant chemotherapy in nasopharyngeal carcinoma (NPC) patients with persistently detectable plasma Epstein-Barr virus DNA (pEBV DNA) after curative radiation therapy plus induction/concurrent chemotherapy. Methods and Materials: The study population consisted of 625 NPC patients with available pEBV DNA levels before and after treatment. Eighty-five patients with persistently detectable pEBV DNA after 1 week of completing radiation therapy were eligible for this retrospective study. Of the 85 patients, 33 were administered adjuvant chemotherapy consisting of oral tegafur-uracil (2 capsules twice daily) for 12 months with (n=4) or without (n=29) preceding intravenous chemotherapy of mitomycin-C, epirubicin, and cisplatin. The remaining 52 patients who did not receive adjuvant chemotherapy served as the control group. Results: Baseline patient characteristics at diagnosis (age, sex, pathologic type, performance status, T classification, N classification, and overall stage), as well as previous treatment modality, were comparable in both arms. After a median follow-up of 70 months for surviving patients, 45.5% (15 of 33 patients) with adjuvant chemotherapy and 71.2% (37 of 52 patients) without adjuvant chemotherapy experienced tumor relapses (P=.0323). There were a significant reduction in distant failure (P=.0034) but not in local or regional recurrence. The 5-year overall survival rate was 71.6% for patients with adjuvant chemotherapy and 28.7% for patients without adjuvant chemotherapy (hazard ratio 0.27; 95% confidence interval 0.17-0.55; P<.0001). Conclusions: Our retrospective data showed that adjuvant chemotherapy can reduce distant failure and improve overall survival in NPC patients with persistently detectable pEBV DNA after curative radiation therapy plus induction/concurrent chemotherapy

  14. High-Sensitivity C-Reactive Protein Complements Plasma Epstein-Barr Virus Deoxyribonucleic Acid Prognostication in Nasopharyngeal Carcinoma: A Large-Scale Retrospective and Prospective Cohort Study

    International Nuclear Information System (INIS)

    Tang, Lin-Quan; Li, Chao-Feng; Chen, Qiu-Yan; Zhang, Lu; Lai, Xiao-Ping; He, Yun; Xu, Yun-Xiu-Xiu; Hu, Dong-Peng; Wen, Shi-Hua; Peng, Yu-Tuan; Chen, Wen-Hui; Liu, Huai; Guo, Shan-Shan; Liu, Li-Ting; Li, Jing; Zhang, Jing-Ping

    2015-01-01

    Purpose: To evaluate the effects of combining the assessment of circulating high-sensitivity C-reactive protein (hs-CRP) with that of Epstein-Barr virus DNA (EBV DNA) in the pretherapy prognostication of nasopharyngeal carcinoma (NPC). Patients and Methods: Three independent cohorts of NPC patients (training set of n=3113, internal validation set of n=1556, and prospective validation set of n=1668) were studied. Determinants of disease-free survival, distant metastasis–free survival, and overall survival were assessed by multivariate analysis. Hazard ratios and survival probabilities of the patient groups, segregated by clinical stage (T1-2N0-1M0, T3-4N0-1M0, T1-2N2-3M0, and T3-4N2-3M0) and EBV DNA load (low or high) alone, and also according to hs-CRP level (low or high), were compared. Results: Elevated hs-CRP and EBV DNA levels were significantly correlated with poor disease-free survival, distant metastasis–free survival, and overall survival in both the training and validation sets. Associations were similar and remained significant after excluding patients with cardiovascular disease, diabetes, and chronic hepatitis B. Patients with advanced-stage disease were segregated by high EBV DNA levels and high hs-CRP level into a poorest-risk group, and participants with either high EBV DNA but low hs-CRP level or high hs-CRP but low EBV DNA values had poorer survival compared with the bottom values for both biomarkers. These findings demonstrate a significant improvement in the prognostic ability of conventional advanced NPC staging. Conclusion: Baseline plasma EBV DNA and serum hs-CRP levels were significantly correlated with survival in NPC patients. The combined interpretation of EBV DNA with hs-CRP levels led to refinement of the risks for the patient subsets, with improved risk discrimination in patients with advanced-stage disease

  15. High-Sensitivity C-Reactive Protein Complements Plasma Epstein-Barr Virus Deoxyribonucleic Acid Prognostication in Nasopharyngeal Carcinoma: A Large-Scale Retrospective and Prospective Cohort Study

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lin-Quan [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Li, Chao-Feng [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Information Technology, Sun Yat-sen University, Guangzhou (China); Chen, Qiu-Yan; Zhang, Lu [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Lai, Xiao-Ping; He, Yun; Xu, Yun-Xiu-Xiu; Hu, Dong-Peng; Wen, Shi-Hua; Peng, Yu-Tuan [ZhongShan School of Medicine, Sun Yat-sen University, Guangzhou (China); Chen, Wen-Hui [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Liu, Huai; Guo, Shan-Shan; Liu, Li-Ting [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Li, Jing [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Zhang, Jing-Ping [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Clinical Laboratory, Sun Yat-sen University, Guangzhou (China); and others

    2015-02-01

    Purpose: To evaluate the effects of combining the assessment of circulating high-sensitivity C-reactive protein (hs-CRP) with that of Epstein-Barr virus DNA (EBV DNA) in the pretherapy prognostication of nasopharyngeal carcinoma (NPC). Patients and Methods: Three independent cohorts of NPC patients (training set of n=3113, internal validation set of n=1556, and prospective validation set of n=1668) were studied. Determinants of disease-free survival, distant metastasis–free survival, and overall survival were assessed by multivariate analysis. Hazard ratios and survival probabilities of the patient groups, segregated by clinical stage (T1-2N0-1M0, T3-4N0-1M0, T1-2N2-3M0, and T3-4N2-3M0) and EBV DNA load (low or high) alone, and also according to hs-CRP level (low or high), were compared. Results: Elevated hs-CRP and EBV DNA levels were significantly correlated with poor disease-free survival, distant metastasis–free survival, and overall survival in both the training and validation sets. Associations were similar and remained significant after excluding patients with cardiovascular disease, diabetes, and chronic hepatitis B. Patients with advanced-stage disease were segregated by high EBV DNA levels and high hs-CRP level into a poorest-risk group, and participants with either high EBV DNA but low hs-CRP level or high hs-CRP but low EBV DNA values had poorer survival compared with the bottom values for both biomarkers. These findings demonstrate a significant improvement in the prognostic ability of conventional advanced NPC staging. Conclusion: Baseline plasma EBV DNA and serum hs-CRP levels were significantly correlated with survival in NPC patients. The combined interpretation of EBV DNA with hs-CRP levels led to refinement of the risks for the patient subsets, with improved risk discrimination in patients with advanced-stage disease.

  16. Deoxyribonucleic Acid and Other Words Students Avoid Speaking Aloud: Evaluating the Role of Pronunciation on Participation in Secondary School Science Classroom Conversations

    Science.gov (United States)

    Beck, Stacie Elizabeth

    Student's verbal participation in science classrooms is an essential element in building the skills necessary for proficiency in scientific literacy and discourse. The myriad of new, multisyllabic vocabulary terms introduced in one year of secondary school biology instruction can overwhelm students and further impede the self-efficacy needed for concise constructions of scientific explanations and arguments. Factors inhibiting students' inclination to answer questions, share ideas and respond to peers in biology classrooms include confidence and self-perceived competence in appropriately speaking the language of science. Providing students with explicit, engaging instruction in methods to develop vocabulary for use in expressing conclusions is critical for expanding comprehension of science concepts. This study fused the recommended strategies for engaging vocabulary instruction with linguistic practices for teaching pronunciation to examine the relationship between a student's ability to pronounce challenging bio-terminology and their propensity to speak in teacher-led, guided classroom discussions. Interviews, surveys, and measurements quantifying and qualifying students' participation in class discussions before and after explicit instruction in pronunciation were used to evaluate the potential of this strategy as an appropriate tool for increasing students' self-efficacy and willingness to engage in biology classroom conversations. The findings of this study showed a significant increase in student verbal participation in classroom discussions after explicit instruction in pronunciation combined with vocabulary literacy strategies. This research also showed an increase in the use of vocabulary words in student comments after the intervention.

  17. Existing and emerging detection technologies for DNA (Deoxyribonucleic Acid) finger printing, sequencing, bio- and analytical chips: a multidisciplinary development unifying molecular biology, chemical and electronics engineering.

    Science.gov (United States)

    Kumar Khanna, Vinod

    2007-01-01

    The current status and research trends of detection techniques for DNA-based analysis such as DNA finger printing, sequencing, biochips and allied fields are examined. An overview of main detectors is presented vis-à-vis these DNA operations. The biochip method is explained, the role of micro- and nanoelectronic technologies in biochip realization is highlighted, various optical and electrical detection principles employed in biochips are indicated, and the operational mechanisms of these detection devices are described. Although a diversity of biochips for diagnostic and therapeutic applications has been demonstrated in research laboratories worldwide, only some of these chips have entered the clinical market, and more chips are awaiting commercialization. The necessity of tagging is eliminated in refractive-index change based devices, but the basic flaw of indirect nature of most detection methodologies can only be overcome by generic and/or reagentless DNA sensors such as the conductance-based approach and the DNA-single electron transistor (DNA-SET) structure. Devices of the electrical detection-based category are expected to pave the pathway for the next-generation DNA chips. The review provides a comprehensive coverage of the detection technologies for DNA finger printing, sequencing and related techniques, encompassing a variety of methods from the primitive art to the state-of-the-art scenario as well as promising methods for the future.

  18. Familial partial lipodystrophy phenotype resulting from a single-base mutation in deoxyribonucleic acid-binding domain of peroxisome proliferator-activated receptor-gamma

    NARCIS (Netherlands)

    Monajemi, Houshang; Zhang, Lin; Li, Gang; Jeninga, Ellen H.; Cao, Henian; Maas, Mario; Brouwer, C. B.; Kalkhoven, Eric; Stroes, Erik; Hegele, Robert A.; Leff, Todd

    2007-01-01

    CONTEXT: Familial partial lipodystrophy (FPLD) results from coding sequence mutations either in LMNA, encoding nuclear lamin A/C, or in PPARG, encoding peroxisome proliferator-activated receptor-gamma (PPARgamma). The LMNA form is called FPLD2 (MIM 151660) and the PPARG form is called FPLD3 (MIM

  19. Chromosomal aberrations and deoxyribonucleic acid single-strand breaks in adipose-derived stem cells during long-term expansion in vitro.

    Science.gov (United States)

    Froelich, Katrin; Mickler, Johannes; Steusloff, Gudrun; Technau, Antje; Ramos Tirado, Mario; Scherzed, Agmal; Hackenberg, Stephan; Radeloff, Andreas; Hagen, Rudolf; Kleinsasser, Norbert

    2013-07-01

    Adipose-derived stem cells (ASCs) are a promising mesenchymal cell source for tissue engineering approaches. To obtain an adequate cell amount, in vitro expansion of the cells may be required in some cases. To monitor potential contraindications for therapeutic applications in humans, DNA strand breaks and chromosomal aberrations in ASCs during in vitro expansion were examined. After isolation of ASC from human lipoaspirates of seven patients, in vitro expansion over 10 passages was performed. Cells from passages 1, 2, 3, 5 and 10 were used for the alkaline single-cell microgel electrophoresis (comet) assay to detect DNA single-strand breaks and alkali labile as well as incomplete excision repair sites. Chromosomal changes were examined by means of the chromosomal aberration test. During in vitro expansion, ASC showed no DNA single-strand breaks in the comet assay. With the chromosomal aberration test, however, a significant increase in chromosomal aberrations were detected. The study showed that although no DNA fragmentation could be determined, the safety of ASC cannot be ensured with respect to chromosome stability during in vitro expansion. Thus, reliable analyses for detecting ASC populations, which accumulate chromosomal aberrations or even undergo malignant transformation during extensive in vitro expansion, must be implemented as part of the safety evaluation of these cells for stem cell-based therapy. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  20. Chemical carcinogenesis in the nervous system. Preferential accumulation of O6-methylguanine in rat brain deoxyribonucleic acid during repetitive administration of N-methyl-N-nitrosourea.

    Science.gov (United States)

    Margison, G P; Kleihues, P

    1975-01-01

    The alkylation of purine bases in DNA of several rat tissues was determined during weekly injections (10 mg/kg) of N-[3H]methyl-N-nitrosourea, a dose schedule known to selectively induce tumours of the nervous system. Each group of animals was killed 1 week after the final injection, and the DNA hydrolysates were analysed by chromatography on Sephadex G-10. After five weekly applications, O6-methylguanine had accumulated in brain DNA to an extent which greatly exceeded that in kidney, spleen and intestine. In the liver, the final O6-methylguanine concentration was less than 1% of that in brain. Between the first and the fifth injection, the O6-methylguanine/7-methylguanine ratio in cerebral DNA increased from 0.28 to 0.68. In addition, 3-methylguanine was found to accumulate in brain DNA whereas in the other organs no significant quantities of this base were detectable. The results are compatible with the hypothesis that O6-alkylation of guanine in DNA plays a major role in the induction of tumours by N-methyl-N-nitrosourea and related carcinogens. The kinetics of the increase of O6-methylguanine in cerebral DNA suggest that there is no major cell fraction in the brain which is capable of excising chemically methylated bases from DNA. This repair deficiency could be a determining factor in the selective induction of nervous-system tumours by N-methyl-N-nitrosourea and other neuro-oncogenic compounds. PMID:1200992

  1. Reaction products from N-methyl-N-nitrosourea and deoxyribonucleic acid containing thymidine residues. Synthesis and identification of a new methylation product, O4-methyl-thymidine

    Science.gov (United States)

    Lawley, P. D.; Orr, D. J.; Shah, S. A.; Farmer, P. B.; Jarman, M.

    1973-01-01

    1. DNA was treated with N-methyl-N-nitrosourea at pH7–8, 37°C, degraded to yield 3- and 7-methylpurines and deoxyribonucleosides and the reaction products were separated by chromatography on ion-exchange resins. The following methods for identification and determination of products were used: with unlabelled N-methyl-N-nitrosourea, u.v. absorption; use of methyl-14C-labelled N-methyl-N-nitrosourea and use of [14C]thymine-labelled DNA. 2. The synthesis of O4-methylthymidine and its identification by u.v. and mass spectroscopy are reported. 3. 3-Methylthymidine and O4-methylthymidine were found as methylation products from N-methyl-N-nitrosourea with thymidine and with DNA, in relatively small yields. Unidentified products containing thymine were found in enzymic digests of N-methyl-N-nitrosourea-treated DNA, which may be phosphotriesters. 4. The possible role of formation of methylthymines in mutagenesis by N-methyl-N-nitrosourea is discussed. PMID:4798180

  2. Exponential Increase in Relative Biological Effectiveness Along Distal Edge of a Proton Bragg Peak as Measured by Deoxyribonucleic Acid Double-Strand Breaks

    Energy Technology Data Exchange (ETDEWEB)

    Cuaron, John J., E-mail: cuaronj@mskcc.org [Memorial Sloan Kettering Cancer Center, New York, New York (United States); Chang, Chang [Texas Center for Proton Therapy, Irving, Texas (United States); Lovelock, Michael; Higginson, Daniel S. [Memorial Sloan Kettering Cancer Center, New York, New York (United States); Mah, Dennis [Procure Proton Therapy Center, Somerset, New Jersey (United States); Cahlon, Oren; Powell, Simon [Memorial Sloan Kettering Cancer Center, New York, New York (United States)

    2016-05-01

    Purpose: To quantify the relative biological effectiveness (RBE) of the distal edge of the proton Bragg peak, using an in vitro assay of DNA double-strand breaks (DSBs). Methods and Materials: U2OS cells were irradiated within the plateau of a spread-out Bragg peak and at each millimeter position along the distal edge using a custom slide holder, allowing for simultaneous measurement of physical dose. A reference radiation signal was generated using photons. The DNA DSBs at 3 hours (to assess for early damage) and at 24 hours (to assess for residual damage and repair) after irradiation were measured using the γH2AX assay and quantified via flow cytometry. Results were confirmed with clonogenic survival assays. A detailed map of the RBE as a function of depth along the Bragg peak was generated using γH2AX measurements as a biological endpoint. Results: At 3 hours after irradiation, DNA DSBs were higher with protons at every point along the distal edge compared with samples irradiated with photons to similar doses. This effect was even more pronounced after 24 hours, indicating that the impact of DNA repair is less after proton irradiation relative to photons. The RBE demonstrated an exponential increase as a function of depth and was measured to be as high as 4.0 after 3 hours and as high as 6.0 after 24 hours. When the RBE-corrected dose was plotted as a function of depth, the peak effective dose was extended 2-3 mm beyond what would be expected with physical measurement. Conclusions: We generated a highly comprehensive map of the RBE of the distal edge of the Bragg peak, using a direct assay of DNA DSBs in vitro. Our data show that the RBE of the distal edge increases with depth and is significantly higher than previously reported estimates.

  3. Preparation of water soluble chitosan by hydrolysis using hydrogen peroxide.

    Science.gov (United States)

    Xia, Zhenqiang; Wu, Shengjun; Chen, Jinhua

    2013-08-01

    Chitosan is not soluble in water, which limits its wide application particularly in the medicine and food industry. In the present study, water soluble chitosan (WSC) was prepared by hydrolyzing chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid in homogeneous phase. Factors affecting hydrolysis were investigated and the optimal hydrolysis conditions were determined. The WSC structure was characterized by Fourier transform infrared spectroscopy. The resulting products were composed of chitooligosaccharides of DP 2-9. The WSC content of the product and the yield were 94.7% and 92.3% (w/w), respectively. The results indicate that WSC can be effectively prepared by hydrolysis of chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Near-field solubility studies

    International Nuclear Information System (INIS)

    Thomason, H.P.; Williams, S.J.

    1992-02-01

    Experimental determinations of the solubilities of americium, plutonium, neptunium, protactinium, thorium, radium, lead, tin, palladium and zirconium are reported. These elements have radioactive isotopes of concern in assessments of radioactive waste disposal. All measurements were made under the highly alkaline conditions typical of the near field of a radioactive waste repository which uses cementitious materials for many of the immobilisation matrices, the backfill and the engineered structures. Low redox potentials, typical of those resulting from the corrosion of iron and steel, were simulated for those elements having more than one accessible oxidation state. The dissolved concentrations of the elements were defined using ultrafiltration. In addition, the corrosion of iron and stainless steel was shown to generate low redox potentials in solution and the solubility of iron(II) at high pH was measured and found to be sufficient for it to act as a redox buffer with respect to neptunium and plutonium. (author)

  5. The Solubility Parameters of Ionic Liquids

    Science.gov (United States)

    Marciniak, Andrzej

    2010-01-01

    The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated. PMID:20559495

  6. The Solubility Parameters of Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Andrzej Marciniak

    2010-04-01

    Full Text Available The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated.

  7. Solubility of Carbon in Nanocrystalline -Iron

    OpenAIRE

    Alexander Kirchner; Bernd Kieback

    2012-01-01

    A thermodynamic model for nanocrystalline interstitial alloys is presented. The equilibrium solid solubility of carbon in -iron is calculated for given grain size. Inside the strained nanograins local variation of the carbon content is predicted. Due to the nonlinear relation between strain and solubility, the averaged solubility in the grain interior increases with decreasing grain size. The majority of the global solubility enhancement is due to grain boundary enrichment however. Therefor...

  8. Soluble inhibitors/deactivators of cellulase enzymes from lignocellulosic biomass.

    Science.gov (United States)

    Kim, Youngmi; Ximenes, Eduardo; Mosier, Nathan S; Ladisch, Michael R

    2011-04-07

    Liquid hot water, steam explosion, and dilute acid pretreatments of lignocellulose generate soluble inhibitors which hamper enzymatic hydrolysis as well as fermentation of sugars to ethanol. Toxic and inhibitory compounds will vary with pretreatment and include soluble sugars, furan derivatives (hydroxymethyl fulfural, furfural), organic acids (acetic, formic and, levulinic acid), and phenolic compounds. Their effect is seen when an increase in the concentration of pretreated biomass in a hydrolysis slurry results in decreased cellulose conversion, even though the ratio of enzyme to cellulose is kept constant. We used lignin-free cellulose, Solka Floc, combined with mixtures of soluble components released during pretreatment of wood, to prove that the decrease in the rate and extent of cellulose hydrolysis is due to a combination of enzyme inhibition and deactivation. The causative agents were extracted from wood pretreatment liquid using PEG surfactant, activated charcoal or ethyl acetate and then desorbed, recovered, and added back to a mixture of enzyme and cellulose. At enzyme loadings of either 1 or 25mg protein/g glucan, the most inhibitory components, later identified as phenolics, decreased the rate and extent of cellulose hydrolysis by half due to both inhibition and precipitation of the enzymes. Full enzyme activity occurred when the phenols were removed. Hence detoxification of pretreated woods through phenol removal is expected to reduce enzyme loadings, and therefore reduce enzyme costs, for a given level of cellulose conversion. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Enhanced Iron Solubility at Low pH in Global Aerosols

    Directory of Open Access Journals (Sweden)

    Ellery D. Ingall

    2018-05-01

    Full Text Available The composition and oxidation state of aerosol iron were examined using synchrotron-based iron near-edge X-ray absorption spectroscopy. By combining synchrotron-based techniques with water leachate analysis, impacts of oxidation state and mineralogy on aerosol iron solubility were assessed for samples taken from multiple locations in the Southern and the Atlantic Oceans; and also from Noida (India, Bermuda, and the Eastern Mediterranean (Crete. These sampling locations capture iron-containing aerosols from different source regions with varying marine, mineral dust, and anthropogenic influences. Across all locations, pH had the dominating influence on aerosol iron solubility. When aerosol samples were approximately neutral pH, iron solubility was on average 3.4%; when samples were below pH 4, the iron solubility increased to 35%. This observed aerosol iron solubility profile is consistent with thermodynamic predictions for the solubility of Fe(III oxides, the major iron containing phase in the aerosol samples. Source regions and transport paths were also important factors affecting iron solubility, as samples originating from or passing over populated regions tended to contain more soluble iron. Although the acidity appears to affect aerosol iron solubility globally, a direct relationship for all samples is confounded by factors such as anthropogenic influence, aerosol buffer capacity, mineralogy and physical processes.

  10. Chemical remediation of wood treated with micronised, nano or soluble copper preservatives

    Science.gov (United States)

    Saip Nami Kartal; Evren Terzi; Bessie Woodward; Carol A. Clausen; Stan T. Lebow

    2013-01-01

    The potential for extraction of copper from wood treated with micronised, nano or soluble forms of copper has been evaluated in view of chemical remediation. In focus were EDTA, oxalic acid, bioxalate, and D-gluconic acid for extraction of Cu from treated wood. Bioxalate extractions for 24 h resulted in Cu removal over 95% for all tested...

  11. Water soluble and efficient amino acid Schiff base receptor for reversible fluorescence turn-on detection of Zn²⁺ ions: Quantum chemical calculations and detection of bacteria.

    Science.gov (United States)

    Subha, L; Balakrishnan, C; Natarajan, Satheesh; Theetharappan, M; Subramanian, Balanehru; Neelakantan, M A

    2016-01-15

    An amino acid Schiff base (R) capable of recognizing Zn(2+) ions selectively and sensitively in an aqueous medium was prepared and characterized. Upon addition of Zn(2+) ions, the receptor exhibits fluorescence intensity enhancements (~40 fold) at 460 nm (quantum yield, Φ=0.05 for R and Φ=0.18 for R-Zn(2+)) and can be detected by naked eye under UV light. The receptor can recognize the Zn(2+) (1.04×10(-8) M) selectively for other metal ions in the pH range of 7.5-11. The Zn(2+) chelation with R decreases the loss of energy through non-radiative transition and leads to fluorescence enhancement. The binding mode of the receptor with Zn(2+) was investigated by (1)H NMR titration and further validated by ESI-MS. The elemental color mapping and SEM/EDS analysis were also used to study the binding of R with Zn(2+). Density functional theory calculations were carried out to understand the binding mechanism. The receptor was applied as a microbial sensor for Escherichia coli and Staphylococcus aureus. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Soluble Non-ammonia Nitrogen in Ruminal and Omasal Digesta of Korean Native Steers Supplemented with Soluble Proteins

    Directory of Open Access Journals (Sweden)

    C. W. Choi

    2012-09-01

    Full Text Available An experiment was conducted to study the effect of soluble protein supplements on concentration of soluble non-ammonia nitrogen (SNAN in the liquid phase of ruminal (RD and omasal digesta (OD of Korean native steers, and to investigate diurnal pattern in SNAN concentration in RD and OD. Three ruminally cannulated Korean native steers in a 3×3 Latin square design consumed a basal diet of rice straw and corn-based concentrate (control, and that supplemented (kg/d DM basis with intact casein (0.24; IC or acid hydrolyzed casein (0.46; AHC. Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 2.0 h intervals after a morning feeding. The SNAN fractions (free amino acid (AA, peptide and soluble protein in RD and OD were assessed using the ninhydrin assay. Concentrations of free AA and total SNAN in RD were significantly (p<0.05 lower than those in OD. Although free AA concentration was relatively high, mean peptide was quantitatively the most important fraction of total SNAN in both RD and OD, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis of Korean native steers. Diurnal variation in peptide concentration in OD for the soluble protein supplemented diets during the feeding cycle peaked 2 h post-feeding and decreased thereafter whereas that for the control was relatively constant during the entire feeding cycle. Diurnal variation in peptide concentration was rather similar between RD and OD.

  13. Metabolizable energy and amino acids relationships with the soluble fractions of protein and fiber of vegetable feed ingredients Energia metabolizável e relações de aminoácidos com as frações solúveis de proteína e fibra de ingredientes vegetais

    Directory of Open Access Journals (Sweden)

    Claudio Bellaver

    2004-12-01

    Full Text Available To estimate nutrient and energy digestion with animal from in vitro variables it is necessary to control factors that may interfere on digestion such as: source and concentration of digestor substance, as well as the origin and processing of test ingredients. In this study there were performed five laboratory assays, two with poultry and finally regression equations were established based on variables generated with twelve vegetable ingredients. The results showed that there is greater solubility of proteins with NaOH than with KOH. On average, both alkali produced better discrimination of soluble protein with concentration of 0.02% (range of 68.61% in relation to a concentration of 0.2% (range of 37.97%. Considering interaction between alkali and concentration, the best discrimination on protein solubility was reached with NaOH at 0.02%. The methods of protein or fiber solubilization together with the chemical analysis showed significant results variation among ingredients and when they were used to estimate in vivo variables they produced good estimates. It was concluded that reliable digestion estimates for energy or amino acids from vegetable feed ingredients could be obtained from in vitro variables, when considering solubilities of protein and fiber with chemical analysis.Para estimar a digestão de nutrientes e de energia dos animais a partir de variáveis in vitro, é necessário controlar os fatores que interferem na digestão - origem e concentração da substância digestora - e ter conhecimento da fonte e do processo que envolve o ingrediente em teste. Neste trabalho, foram conduzidos cinco ensaios laboratoriais, dois com animais e, por fim, estabelecidas equações de regressão a partir das variáveis geradas com a utilização de 12 ingredientes vegetais. Os resultados mostraram que há maior solubilidade das proteínas com o NaOH que com o KOH e que, na média de ambos os álcalis, a concentração de 0,02% permite maior

  14. Solubilities of iron and nickel oxides under high temperature and high pressure conditions

    International Nuclear Information System (INIS)

    Choi, Ke-Chon; Jung, Yong-Ju; Yeon, Jei-Won; Jee, Kwang-Yong

    2007-01-01

    The purposes of primary coolant chemistry are to assure fuel and material integrity and to minimize out of core radiation fields. During the PWR operation, crud deposits are expected on the cladding, leading to cladding failure and raising the radioactivity. Such deposits come from the corrosion products of system surface. To achieve optimal conditions for primary coolant, basic researches on mass transfer, deposition and solubility of corrosion products are needed. The initial stage of crud formation could be the studies on the solubility of a structural material. It has been known that the solubility of metal oxides in boric acid under high temperature and high pressure condition depends on the pH and dissolved hydrogen. Thus, the effect of various pH on the solubility of metal oxide in boric acid solution was investigated in this work

  15. Water-Soluble Vitamin E-Tocopheryl Phosphate.

    Science.gov (United States)

    Zingg, Jean-Marc

    The hydrophobicity of vitamin E poses transport and metabolic challenges to regulate its bioavailability and to prevent its accumulation in lipid-rich tissues such as adipose tissue, brain, and liver. Water-soluble precursors of vitamin E (α-tocopherol, αT), such as its esters with acetate (αTA), succinate (αTS), or phosphate (αTP), have increased solubility in water and stability against reaction with free radicals, but they are rapidly converted during their uptake into the lipid-soluble vitamin E. Therefore, the bioavailability of these precursors as intact molecules is low; nevertheless, at least for αTS and αTP, the recent research has revealed unique regulatory effects on signal transduction and gene expression and the modulation of cellular events ranging from proliferation, survival/apoptosis, lipid uptake and metabolism, phagocytosis, long term potentiation, cell migration, telomere maintenance, and angiogenesis. Moreover, water-soluble derivatives of vitamin E including some based on αTP are increasingly used as components of nanocarriers for enhanced and targeted delivery of drugs and other molecules (vitamins, including αT and αTP itself, vitamin D3, carnosine, caffeine, docosahexaenoic acid (DHA), insulin) and cofactors such as coenzyme Q10. In this review, the chemical characteristics, transport, metabolic pathways, and molecular mechanisms of action of αTP in cells and tissues are summarized and put into perspective with its possible role in the prevention of a number of diseases. © 2018 Elsevier Inc. All rights reserved.

  16. Novel furosemide cocrystals and selection of high solubility drug forms.

    Science.gov (United States)

    Goud, N Rajesh; Gangavaram, Swarupa; Suresh, Kuthuru; Pal, Sharmistha; Manjunatha, Sulur G; Nambiar, Sudhir; Nangia, Ashwini

    2012-02-01

    Furosemide was screened in cocrystallization experiments with pharmaceutically acceptable coformer molecules to discover cocrystals of improved physicochemical properties, that is high solubility and good stability. Eight novel equimolar cocrystals of furosemide were obtained by liquid-assisted grinding with (i) caffeine, (ii) urea, (iii) p-aminobenzoic acid, (iv) acetamide, (v) nicotinamide, (vi) isonicotinamide, (vii) adenine, and (viii) cytosine. The product crystalline phases were characterized by powder x-ray diffraction, differential scanning calorimetry, infrared, Raman, near IR, and (13) C solid-state NMR spectroscopy. Furosemide-caffeine was characterized as a neutral cocrystal and furosemide-cytosine an ionic salt by single crystal x-ray diffraction. The stability of furosemide-caffeine, furosemide-adenine, and furosemide-cytosine was comparable to the reference drug in 10% ethanol-water slurry; there was no evidence of dissociation of the cocrystal to furosemide for up to 48 h. The other five cocrystals transformed to furosemide within 24 h. The solubility order for the stable forms is furosemide-cytosine > furosemide-adenine > furosemide-caffeine, and their solubilities are approximately 11-, 7-, and 6-fold higher than furosemide. The dissolution rates of furosemide cocrystals were about two times faster than the pure drug. Three novel furosemide compounds of higher solubility and good phase stability were identified in a solid form screen. Copyright © 2011 Wiley Periodicals, Inc.

  17. Optimization of translation profiles enhances protein expression and solubility.

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Hess

    Full Text Available mRNA is translated with a non-uniform speed that actively coordinates co-translational folding of protein domains. Using structure-based homology we identified the structural domains in epoxide hydrolases (EHs and introduced slow-translating codons to delineate the translation of single domains. These changes in translation speed dramatically improved the solubility of two EHs of metagenomic origin in Escherichia coli. Conversely, the importance of transient attenuation for the folding, and consequently solubility, of EH was evidenced with a member of the EH family from Agrobacterium radiobacter, which partitions in the soluble fraction when expressed in E. coli. Synonymous substitutions of codons shaping the slow-transiting regions to fast-translating codons render this protein insoluble. Furthermore, we show that low protein yield can be enhanced by decreasing the free folding energy of the initial 5'-coding region, which can disrupt mRNA secondary structure and enhance ribosomal loading. This study provides direct experimental evidence that mRNA is not a mere messenger for translation of codons into amino acids but bears an additional layer of information for folding, solubility and expression level of the encoded protein. Furthermore, it provides a general frame on how to modulate and fine-tune gene expression of a target protein.

  18. Modifications of the acidic soluble salivary proteome in human children from birth to the age of 48months investigated by a top-down HPLC-ESI-MS platform.

    Science.gov (United States)

    Manconi, B; Cabras, T; Pisano, E; Sanna, M T; Olianas, A; Fanos, V; Faa, G; Nemolato, S; Iavarone, F; Castagnola, M; Messana, I

    2013-10-08

    During the first year of life the infant oral environment undergoes dramatic changes. To investigate how the salivary proteome of human children evolves during infant development we have analyzed whole saliva of 88 children aged between 0 and 48months by a top-down platform based on RP-HPLC-ESI-MS. Children were divided according to their age into five groups (A, 0-6months, N=17; B, 7-12months, N=14; C, 13-24months, N=32; D, 25-36months, N=16; E, 37-48months, N=9). The proteins and peptides analyzed were histatins (histatin-1, histatin-3 1/24), acidic proline-rich proteins, statherin, P-B peptide, and salivary cystatins. Protein and peptide quantification based on the area of the RP-HPLC-ESI-MS extracted ion current peak evidenced that: (i) concentrations of the major salivary proteins/peptides showed a minimum in the 0-6-month-old group and increased with age; (ii) the level of histatin-1 reached a maximum in the 7-12-month-old group, a minimum in the 13-24-month-aged babies and it increased again in the 25-36-month-old group; (iii) S-type cystatins were almost undetectable in the 0-6-month-old group; (iv) P-B peptide concentration greatly increased with age; (v) histatin-3 1/24 and statherin concentrations did not show any age-related variation. The top-down proteomic approach undertaken in this work reveals that the salivary proteome of human children from birth to 48months of age shows important quantitative modifications. The concentrations of the major salivary proteins, with the exception of statherin and histatin-3 1/24, showed a minimum in the 0-6-month-old group when the expression in salivary glands is probably not fully activated. Concentrations of the salivary proteins slowly increased with age, with different trends. Only histatin-1 showed the highest concentration in the 7-12-month-old group, followed by a decrease in the 13-24-month-aged children. This particular trend could be related to the phenomenon of eruption of primary dentition. This study

  19. pH-dependent solubility of indomethacin-saccharin and carbamazepine-saccharin cocrystals in aqueous media.

    Science.gov (United States)

    Alhalaweh, Amjad; Roy, Lilly; Rodríguez-Hornedo, Naír; Velaga, Sitaram P

    2012-09-04

    Cocrystals constitute an important class of pharmaceutical solids for their remarkable ability to modulate solubility and pH dependence of water insoluble drugs. Here we show how cocrystals of indomethacin-saccharin (IND-SAC) and carbamazepine-saccharin (CBZ-SAC) enhance solubility and impart a pH-sensitivity different from that of the drugs. IND-SAC exhibited solubilities 13 to 65 times higher than IND at pH values of 1 to 3, whereas CBZ-SAC exhibited a 2 to 10 times higher solubility than CBZ dihydrate. Cocrystal solubility dependence on pH predicted from mathematical models using cocrystal K(sp), and cocrystal component K(a) values, was in excellent agreement with experimental measurements. The cocrystal solubility increase relative to drug was predicted to reach a limiting value for a cocrystal with two acidic components. This limiting value is determined by the ionization constants of cocrystal components. Eutectic constants are shown to be meaningful indicators of cocrystal solubility and its pH dependence. The two contributions to solubility, cocrystal lattice and solvation, were evaluated by thermal and solubility determinations. The results show that solvation is the main barrier for the aqueous solubility of these drugs and their cocrystals, which are orders of magnitude higher than their lattice barriers. Cocrystal increase in solubility is thus a result of decreasing the solvation barrier compared to that of the drug. This work demonstrates the favorable properties of cocrystals and strategies that facilitate their meaningful characterization.

  20. Cocrystals of Hydrochlorothiazide: Solubility and Diffusion/Permeability Enhancements through Drug-Coformer Interactions.

    Science.gov (United States)

    Sanphui, Palash; Devi, V Kusum; Clara, Deepa; Malviya, Nidhi; Ganguly, Somnath; Desiraju, Gautam R

    2015-05-04

    Hydrochlorothiazide (HCT) is a diuretic and a BCS class IV drug with low solubility and low permeability, exhibiting poor oral absorption. The present study attempts to improve the physicochemical properties of the drug using a crystal engineering approach with cocrystals. Such multicomponent crystals of HCT with nicotinic acid (NIC), nicotinamide (NCT), 4-aminobenzoic acid (PABA), succinamide (SAM), and resorcinol (RES) were prepared using liquid-assisted grinding, and their solubilities in pH 7.4 buffer were evaluated. Diffusion and membrane permeability were studied using a Franz diffusion cell. Except for the SAM and NIC cocrystals, all other binary systems exhibited improved solubility. All of the cocrystals showed improved diffusion/membrane permeability compared to that of HCT with the exception of the SAM cocrystal. When the solubility was high, as in the case of PABA, NCT, and RES cocrystals, the flux/permeability dropped slightly. This is in agreement with the expected interplay between solubility and permeability. Improved solubility/permeability is attributed to new drug-coformer interactions. Cocrystals of SAM, however, showed poor solubility and flux. This cocrystal contains a primary sulfonamide dimer synthon similar to that of HCT polymorphs, which may be a reason for its unusual behavior. Hirshfeld surface analysis was carried out in all cases to determine whether a correlation exists between cocrystal permeability and drug-coformer interactions.

  1. Poster 34. Monitoring of soluble species in the NPTEC SCEPTRE loop

    International Nuclear Information System (INIS)

    Eley, C.D.; Thomas, D.M.; Libaert, D.F.; Cattell, R.A.; Garbett, K.; Woolsey, I.S.

    1992-01-01

    Soluble transition metal ion and other species were measured in the coolant of the SCEPTRE Loop under PWR primary circuit conditions typical of the hot functional test and normal load operation. Good consistency between lines was observed for stainless steel sample lines with relatively high linear flow rates, rapid cooling to near ambient temperature and PTFE lining downstream of the cooler. Phenomenological conditioning times of the order of 100 hours for soluble transition metal species were determined for this type of sampling system. The behaviour of soluble transition metal species in a static, aerated stainless steel tank containing boric acid solutions was also investigated. (author)

  2. Study of N-cinnamoylphenylhydroxylaminate solubility in water and organic solvents

    International Nuclear Information System (INIS)

    Pilipenko, A.T.; Shpak, Eh.A.; Samchuk, A.I.

    1975-01-01

    The composition of complexes of N-cinnamoylphenylhydroxylamine with copper, cadmium, lead, indium, iron, gallium, titanium, zirconium, hafnium, niobium, tantalum, tungsten, molybdenum and vanadium was determined. The solubility products of the N-cinnamoylphenylhydroxylaminates of copper, cadmium, indium, gallium and iron were determined by the method of measuring the solubility of precipitates in acid. The solubility of N-cinnamoylphenylhydroxalaminates of cadmium, indium, iron, titanium, zirconium, hafnium, niobium, tantalum, vanadium, molybdenum and tungsten in organic solvents was studied. Two-phase constants for the stability of the complexes were calculated. (author)

  3. Preparation of fulvic acid and low-molecular organic acids by oxidation of weathered coal humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Shinozuka, T.; Ito, A.; Sasaki, O.; Yazawa, Y.; Yamaguchi, T. [Chiba Institute of Technolgy, Chiba (Japan). Dept. of Industrial Chemistry

    2002-07-01

    Weathered coal contains much humic acid and a little fulvic acid. Therefore, the production of fulvic acid, the most valuable humic substance because of its water-solubility, was examined by ozone and hydrogen peroxide oxidation of humic acid extracted form Xinjiang (China) weathered coal. The resulting products of the oxidation were water soluble fulvic acid and organic acids, mainly formic acid and oxalic acid. The product yield of fulvic acid was 20 (C%) and that of organic acids were 39 (C%) for formic and acid 13 (C%) for oxalic acid. The formed fulvic acid showed a higher content of oxygen and carboxyl groups, than those of the extracted one from the original weathered coal.

  4. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S.; Debapriya, M. [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India); Nagaraja, V. [Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012 (India); Raichur, Ashok M., E-mail: amr@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India)

    2011-03-12

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO{sub 3} particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  5. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    International Nuclear Information System (INIS)

    Anandhakumar, S.; Debapriya, M.; Nagaraja, V.; Raichur, Ashok M.

    2011-01-01

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO 3 particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  6. Dietary supplementation with docosahexaenoic acid (DHA) improves seminal antioxidant status and decreases sperm DNA fragmentation.

    Science.gov (United States)

    Martínez-Soto, Juan Carlos; Domingo, Joan Carles; Cordobilla, Begoña; Nicolás, María; Fernández, Laura; Albero, Pilar; Gadea, Joaquín; Landeras, José

    2016-12-01

    The purpose of this study was to evaluate the effect of docosahexaenoic acid (DHA) dietary supplementation on semen quality, fatty acid composition, antioxidant capacity, and DNA fragmentation. In this randomized, double blind, placebo-controlled, parallel-group study, 74 subjects were recruited and randomly assigned to either the placebo group (n=32) or to the DHA group (n=42) to consume three 500-mg capsules of oil per day over 10 weeks. The placebo group received 1,500 mg/day of sunflower oil and the DHA group 1,500 mg/day of DHA-enriched oil. Seminal parameters (semen volume, sperm concentration, motility, morphology, and vitality), total antioxidant capacity, deoxyribonucleic acid fragmentation, and lipid composition were evaluated prior to the treatment and after 10 weeks. Finally, 57 subjects were included in the study with 25 in the placebo group and 32 in the DHA group. No differences were found in traditional sperm parameters or lipid composition of the sperm membrane after treatment. However, an increase in DHA and Omega-3 fatty acid content in seminal plasma, an improvement in antioxidant status, and a reduction in the percentage of spermatozoa with deoxyribonucleic acid damage were observed in the DHA group after 10 weeks of treatment.

  7. The effect of change in pH on the solubility of iron bis-glycinate chelate and other iron compounds.

    Science.gov (United States)

    García-Casal, M N; Layrisse, M

    2001-03-01

    The effect of a pH change from 2 to 6 was tested on the solubility of ferrous sulfate, ferrous fumarate, iron bis-glycine chelate (Ferrochel) and sodium-iron ethylenediaminetetraacetic acid (NaFeEDTA). It was found that at pH 2 ferrous sulfate, Ferrochel and NaFeEDTA were completely soluble and only 75% of iron from ferrous fumarate was soluble. When pH was raised to 6, iron from amino acid chelate and NaFeEDTA remained completely soluble while solubility from ferrous sulfate and ferrous fumarate decreased 64 and 74%, respectively compared to the amount of iron initially soluble at pH 2. These results suggest that iron solubility from iron bis-glycine chelate and NaFeEDTA is not affected by pH changes within the ranges tested, probably because iron remained associated to the respective compounds.

  8. Identification of the soluble HVP-associated antigen of the lymphoblastoid cell line established from lymphomatous baboon (Papio hamadryas).

    Science.gov (United States)

    Voevodin, A F; Lapin, B A; Agrba, V Z; Timanovskaya, V V

    1978-01-01

    A new technique (indirect double immunodiffusion) for detection of EBV-associated soluble antigen and corresponding antibodies has been developed. This technique includes three steps: 1) simple double immunodiffusion with extracts of Raji cells (or other EBV-genome positive cells) and human sera containing antibodies against EBV-associated soluble antigen; 2) extensive washing and treatment with anti-human globulin; 3) extensive washing and treatment with tannic acid. Using this test it was shown that the soluble antigen indistinguishable from EBV-associated soluble antigen was present in KMPG-1 cells producing HVP.

  9. Water soluble inorganic trace gases and related aerosol compounds in the tropical boundary layer. An analysis based on real time measurements at a pasture site in the Amazon Basin

    NARCIS (Netherlands)

    Trebs, I.

    2005-01-01

    This dissertation investigates the behavior of water-soluble inorganic trace gases and related aerosol species in the tropical boundary layer. Mixing ratios of ammonia (NH3), nitric acid (HNO3), nitrous acid (HONO), hydrochloric acid (HCl), sulfur dioxide (SO;,) and the corresponding water-soluble

  10. Nanosuspension Technology for Solubilizing Poorly Soluble Drugs

    OpenAIRE

    Deoli Mukesh

    2012-01-01

    Poor water solubility for many drugs and drug candidates remains a major obstacle to their development and clinical application. It is estimated that around 40% of drugs in the pipeline cannot be delivered through the preferred route or in some cases, at all owing to poor water solubility. Conventional formulations to improve solubility suffer from low bioavailability and poor pharmacokinetics, with some carriers rendering systemic toxicities (e.g. Cremophor1 EL). To date, nanoscale systems f...

  11. Soluble theory with massive ghosts

    International Nuclear Information System (INIS)

    Pisarski, R.D.

    1983-01-01

    To investigate the unitarity of asymptotically free, higher-derivative theories, like certain models of quantum gravity, I study a prototype in two space-time dimensions. The prototype is a kind of higher-derivative nonlinear sigma model; it is asymptotically free, exhibits dimensional transmutation, and is soluble in a large-N expansion. The S-matrix elements, constructed from the analytic continuation of the Euclidean Green's functions, conserve probability to approx.O(N -1 ), but violate unitarity at approx.O(N -2 ). The model demonstrates that in higher-derivative theories unitarity, or the lack thereof, cannot be decided without explicit control over the infrared limit. Even so, the results suggest that there may exist some (rather special) asymptotically free, higher-derivative theories which are unitary

  12. Removal of Water-Soluble Extractives Improves the Enzymatic Digestibility of Steam-Pretreated Softwood Barks.

    Science.gov (United States)

    Frankó, Balázs; Carlqvist, Karin; Galbe, Mats; Lidén, Gunnar; Wallberg, Ola

    2018-02-01

    Softwood bark contains a large amounts of extractives-i.e., soluble lipophilic (such as resin acids) and hydrophilic components (phenolic compounds, stilbenes). The effects of the partial removal of water-soluble extractives before acid-catalyzed steam pretreatment on enzymatic digestibility were assessed for two softwood barks-Norway spruce and Scots pine. A simple hot water extraction step removed more than half of the water-soluble extractives from the barks, which improved the enzymatic digestibility of both steam-pretreated materials. This effect was more pronounced for the spruce than the pine bark, as evidenced by the 30 and 11% glucose yield improvement, respectively, in the enzymatic digestibility. Furthermore, analysis of the chemical composition showed that the acid-insoluble lignin content of the pretreated materials decreased when water-soluble extractives were removed prior to steam pretreatment. This can be explained by a decreased formation of water-insoluble "pseudo-lignin" from water-soluble bark phenolics during the acid-catalyzed pretreatment, which otherwise results in distorted lignin analysis and may also contribute to the impaired enzymatic digestibility of the barks. Thus, this study advocates the removal of extractives as the first step in the processing of bark or bark-rich materials in a sugar platform biorefinery.

  13. Retrograde curves of solidus and solubility

    International Nuclear Information System (INIS)

    Vasil'ev, M.V.

    1979-01-01

    The investigation was concerned with the constitutional diagrams of the eutectic type with ''retrograde solidus'' and ''retrograde solubility curve'' which must be considered as diagrams with degenerate monotectic transformation. The solidus and the solubility curves form a retrograde curve with a common retrograde point representing the solubility maximum. The two branches of the Aetrograde curve can be described with the aid of two similar equations. Presented are corresponding equations for the Cd-Zn system and shown is the possibility of predicting the run of the solubility curve

  14. Solubility limits of importance to leaching

    International Nuclear Information System (INIS)

    Ogard, A.; Bentley, G.; Bryant, E.; Duffy, C.; Grisham, J.; Norris, E.; Orth, C.; Thomas, K.

    1981-01-01

    The solubilities of some radionuclides, especially rare earths and actinides, may be an important and controlling factor in leaching of waste forms. These solubilities should be measured accurately as a function of pH and not as a part of a multicomponent system. Individual solubilities should be measured as a function of temperature to determine if a kinetic effect is being observed in the data. A negative temperature coefficient of solubility for actinides and rare earths in water would have important consequences for nuclear reactor safety and for the management of nuclear wastes

  15. Solubility Temperature Dependence Predicted from 2D Structure

    Directory of Open Access Journals (Sweden)

    Alex Avdeef

    2015-12-01

    Full Text Available The objective of the study was to find a computational procedure to normalize solubility data determined at various temperatures (e.g., 10 – 50 oC to values at a “reference” temperature (e.g., 25 °C. A simple procedure was devised to predict enthalpies of solution, ΔHsol, from which the temperature dependence of intrinsic (uncharged form solubility, log S0, could be calculated. As dependent variables, values of ΔHsol at 25 °C were subjected to multiple linear regression (MLR analysis, using melting points (mp and Abraham solvation descriptors. Also, the enthalpy data were subjected to random forest regression (RFR and recursive partition tree (RPT analyses. A total of 626 molecules were examined, drawing on 2040 published solubility values measured at various temperatures, along with 77 direct calori    metric measurements. The three different prediction methods (RFR, RPT, MLR all indicated that the estimated standard deviations in the enthalpy data are 11-15 kJ mol-1, which is concordant with the 10 kJ mol-1 propagation error estimated from solubility measurements (assuming 0.05 log S errors, and consistent with the 7 kJ mol-1 average reproducibility in enthalpy values from interlaboratory replicates. According to the MLR model, higher values of mp, H‑bond acidity, polarizability/dipolarity, and dispersion forces relate to more positive (endothermic enthalpy values. However, molecules that are large and have high H-bond basicity are likely to possess negative (exothermic enthalpies of solution. With log S0 values normalized to 25 oC, it was shown that the interlaboratory average standard deviations in solubility measurement are reduced to 0.06 ‑ 0.17 log unit, with higher errors for the least-soluble druglike molecules. Such improvements in data mining are expected to contribute to more reliable in silico prediction models of solubility for use in drug discovery.

  16. Studies on dissolution enhancement and mathematical modeling of drug release of a poorly water-soluble drug using water-soluble carriers.

    Science.gov (United States)

    Ahuja, Naveen; Katare, Om Prakash; Singh, Bhupinder

    2007-01-01

    Role of various water-soluble carriers was studied for dissolution enhancement of a poorly soluble model drug, rofecoxib, using solid dispersion approach. Diverse carriers viz. polyethylene glycols (PEG 4000 and 6000), polyglycolized fatty acid ester (Gelucire 44/14), polyvinylpyrollidone K25 (PVP), poloxamers (Lutrol F127 and F68), polyols (mannitol, sorbitol), organic acid (citric acid) and hydrotropes (urea, nicotinamide) were investigated for the purpose. Phase-solubility studies revealed AL type of curves for each carrier, indicating linear increase in drug solubility with carrier concentration. The sign and magnitude of the thermodynamic parameter, Gibbs free energy of transfer, indicated spontaneity of solubilization process. All the solid dispersions showed dissolution improvement vis-à-vis pure drug to varying degrees, with citric acid, PVP and poloxamers as the most promising carriers. Mathematical modeling of in vitro dissolution data indicated the best fitting with Korsemeyer-Peppas model and the drug release kinetics primarily as Fickian diffusion. Solid state characterization of the drug-poloxamer binary system using XRD, FTIR, DSC and SEM techniques revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement in dissolution rate.

  17. Peptide Nucleic Acids Having Amino Acid Side Chains

    DEFF Research Database (Denmark)

    1998-01-01

    A novel class of compounds, known as peptide nucleic acids, bind complementary DNA and RNA strands more strongly than the corresponding DNA or RNA strands, and exhibit increased sequence specificity and solubility. The peptide nucleic acids comprise ligands selected from a group consisting...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Pantothenic acid and biotin

    Science.gov (United States)

    Pantothenic acid and biotin are types of B vitamins. They are water-soluble, which means that the body can't store them. If the body can't use all of the vitamin, the extra vitamins leave the body through the ...

  20. Determination of soluble protein contents from RVNRL

    International Nuclear Information System (INIS)

    Wan Manshol Wan Zin; Nurulhuda Othman

    1996-01-01

    This project was carried out to determine the soluble protein contents on RVNRL film vulcanisates, with respect to the RVNRL storage time, gamma irradiation dose absorbed by the latex and the effect of different leaching time and leaching conditions. These three factors are important in the hope to determine the best possible mean of minimizing the soluble protein contents in products made from RVNRL. Within the nine months storage period employed in the study, the results show that, the longer the storage period the less the soluble protein extracted from the film samples. Gamma irradiation dose absorbed by the samples, between 5.3 kGy to 25.2 kGy seems to influence the soluble protein contents of the RVNRL films vulcanisates. The higher the dose the more was the soluble protein extracted from the film samples. At an absorbed dose of 5.3 kGy and 25.2 kGy, the soluble contents were 0. 198 mg/ml and 0.247 mg/ml respectively. At a fixed leaching temperature, the soluble proteins increases with leaching time and at a fixed leaching time, the soluble proteins increases with leaching temperature. ne highest extractable protein contents was determined at a leaching time of 10 minutes and leaching temperature of 90'C The protein analysis were done by using Modified Lowry Method