Science.gov

Sample records for 3 7 8

  1. 40 CFR 721.9504 - Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8-tridecafluorooctyl)-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Silane, triethoxy (3,3,4,4,5,5, 6,6,7... Significant New Uses for Specific Chemical Substances § 721.9504 Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8... substance identified as silane, triethoxy (3,3,4,4,5, 5,6,6,7,7,8,8,8-tridecafluorooctyl)- (PMN...

  2. 40 CFR 721.9504 - Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8-tridecafluorooctyl)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Silane, triethoxy (3,3,4,4,5,5, 6,6,7... Significant New Uses for Specific Chemical Substances § 721.9504 Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8... substance identified as silane, triethoxy (3,3,4,4,5, 5,6,6,7,7,8,8,8-tridecafluorooctyl)- (PMN...

  3. 40 CFR 721.9504 - Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8-tridecafluorooctyl)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Silane, triethoxy (3,3,4,4,5,5, 6,6,7... Significant New Uses for Specific Chemical Substances § 721.9504 Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8... substance identified as silane, triethoxy (3,3,4,4,5, 5,6,6,7,7,8,8,8-tridecafluorooctyl)- (PMN...

  4. 40 CFR 721.9504 - Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8-tridecafluorooctyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Silane, triethoxy (3,3,4,4,5,5, 6,6,7... Significant New Uses for Specific Chemical Substances § 721.9504 Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8... substance identified as silane, triethoxy (3,3,4,4,5, 5,6,6,7,7,8,8,8-tridecafluorooctyl)- (PMN...

  5. 40 CFR 721.9504 - Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8-tridecafluorooctyl)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Silane, triethoxy (3,3,4,4,5,5, 6,6,7... Significant New Uses for Specific Chemical Substances § 721.9504 Silane, triethoxy (3,3,4,4,5,5, 6,6,7,7,8,8,8... substance identified as silane, triethoxy (3,3,4,4,5, 5,6,6,7,7,8,8,8-tridecafluorooctyl)- (PMN...

  6. 2,3,7,8-Tetrachlorodibenzo-p-dioxin

    Integrated Risk Information System (IRIS)

    2,3,7,8 - Tetrachlorodibenzo - p - dioxin ( TCDD ) ; CASRN 1746 - 01 - 6 This document has been provided for review to EPA scientists , interagency reviewers from other federal agencies and White House offices , and the public , and peer reviewed by independent scientists external to EPA . Sections

  7. Radioimmunoassay for quantitation of 2,3,7,8-tetrachlorodibenzofuran

    SciTech Connect

    Luster, M.I.; Albro, P.W.; Chae, K.; Lawson, L.D.; Corbett, J.T.; McKinney, J.D.

    1980-08-01

    A radioimmunoassay is described for the determination of 2,3,7,8-tetrachlorodibenzofuran (TCDF) in commercial preparations of polychlorinated biphenyls (PCBs) as well as environmental samples including animal tissues. A feature of the assay method is the use of nonionic detergent to solubilize the hydrophobic dibenzofurans in a manner permitting their binding to antibodies. The detection limits of the assay range between 20 pg and 4.0 ng of 2,3,7,8-TCDF. Extensive cross-reactivity studies indicated that the antiserum was fairly specific for TCDF although some cross-reactivity was found to structurally similar compounds. Values for TCDF in various Aroclors and animal tissues by radioimmunoassay correlated with those obtained by gas chromatography-mass spectrometry analysis. The radioimmunoassay is applicable to screening samples in order to minimize the demand for mass spectrometric screening and should be simple enough to be performed in most clinical laboratories. 3 tables, 1 figure.

  8. 40 CFR 721.9503 - Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)trimethoxy-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9503 Silane, (3,3,4,4,5,5,6,6,7,7,8,8... subject to reporting. (1) The chemical substance identified as silane,...

  9. 40 CFR 721.9503 - Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)trimethoxy-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9503 Silane, (3,3,4,4,5,5,6,6,7,7,8,8... subject to reporting. (1) The chemical substance identified as silane,...

  10. 40 CFR 721.9503 - Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)trimethoxy-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9503 Silane, (3,3,4,4,5,5,6,6,7,7,8,8... subject to reporting. (1) The chemical substance identified as silane,...

  11. 40 CFR 721.9503 - Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)trimethoxy-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9503 Silane, (3,3,4,4,5,5,6,6,7,7,8,8... subject to reporting. (1) The chemical substance identified as silane,...

  12. 40 CFR 721.9503 - Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)trimethoxy-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Silane, (3,3,4,4,5,5,6,6,7,7,8,8,9,9... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9503 Silane, (3,3,4,4,5,5,6,6,7,7,8,8... subject to reporting. (1) The chemical substance identified as silane,...

  13. ARTICLES: Theoretical Study on Destruction Mechanism of 2,3,7,8-TCDD by O3 and NO3

    NASA Astrophysics Data System (ADS)

    Wang, Zhi-hua; Wen, Zheng-cheng; Xu, Jiang-rong; Zhou, Jun-hu; Cen, Ke-fa

    2010-06-01

    In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin (2,3,7,8-TCDD) by O3 and NO3, were investigated employing quantum chemical calculations. For involved reactions, the microcosmic reaction processes were analyzed and depicted in detail based on geometry optimizations made by the B3LYP/6-31G(d) method. At the same time, the reaction activation energies were also calculated at the MP2/6-311G(d,p)//B3LYP/6-31G(d) level. Configuration analysis indicated that 2,3,7,8-TCDD could be destroyed by O3 and NO3 in two different ways. The destruction of 2,3,7,8-TCDD by O3 proceeded via the addition of O3 and the cleavage of C = C while the destruction of 2,3,7,8-TCDD by NO3 proceeded via the substitution of chlorine by NO3. Calculated results show that, the activation energy of the destruction reaction of 2,3,7,8-TCDD by NO3 (267.48 kJ/mol) is much larger than that of the destruction reaction of 2,3,7,8-TCDD by O3 (51.20 kJ/mol). This indicated that the destruction of 2,3,7,8-TCDD by O3 is much more efficient than that of 2,3,7,8-TCDD by NO3. The reason why the activation energy for the destruction reaction of 2,3,7,8-TCDD by NO3 is so large, is also discussed.

  14. Bioavailability of 2,3,7,8-TCDD, 2,3,7,8-TCDF and PCBs to marine benthos from passaic river sediments

    SciTech Connect

    Rubinstein, N.I.; Pruell, R.J.; Taplin, B.K.; LiVolsi, J.A.; Norwood, C.B.

    1990-01-01

    The bioaccumulation and depuration of 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran and polychlorinated biphenyls by marine benthos exposed to environmentally contaminated sediment were measured in a laboratory study. Sandworms (Nereis virens), clams (Macoma nasuta) and shrimp (Palaemonetes pugio) were exposed to sediment from the Passaic River, New Jersey for up to 180 days. Worms accumulated the highest concentrations of these compounds. Uptake and depuration rates were slowest in the worms and most rapid in the clams.

  15. Synthesis and characterization of p-type conductivity dopant 2-(3-(adamantan-1-yl)propyl)-3,5,6-trifluoro-7,7,8,8-tetracyanoquinodimethane

    SciTech Connect

    Rainbolt, James E.; Koech, Phillip K.; Polikarpov, Evgueni; Swensen, James S.; Cosimbescu, Lelia; Von Ruden, Amber L.; Wang, Liang; Sapochak, Linda S.; Padmaperuma, Asanga B.; Gaspar, Daniel J.

    2013-01-22

    We report the synthesis and characterization of 2-(3-(adamantan-1-yl)propyl)-3,5,6-trifluoro-7,7,8,8-tetracyanoquinodimethane (F3TCNQ-Ad1), a substituted analog of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), designed for p-type conductivity doping. The dopant is designed as a model for substituted alternatives to F4TCNQ that maintain similar electronic properties with the goal of engineering dopants with superior fabrication characteristics over F4TCNQ. We describe the design strategy for F3TCNQ-Ad1 based on molecular modeling predictions that substitution of a single fluorine atom of F4TCNQ has little effect on the electronic properties of the molecule. Photophysical and electrochemical characterization reveal that the adamantyl substituent in F3TCNQ-Ad1 does not significantly alter the electronic properties of the substituted dopant relative to F4TCNQ. Unfortunately, F3TCNQ-Ad1 degrades under standard sublimation conditions, preventing sublimation deposition processing. Instead, hole-only devices were made via solution-processing of the p-doped films with the structure glass/ITO/2.3 x103Å PVK:(MTDATA:dopant)/2.0x102Å Au/1.0x103Å Al, where dopant is either F4TCNQ or F3TCNQ-Ad1. We demonstrate that F3TCNQ-Ad1 increased the conductivity of the films by at least 1,000 times compared to an undoped device.

  16. Effects of 2,3,7,8-TCDD on the larvae of fathead minnows (Pimephales promelas)

    SciTech Connect

    Olivieri, C.E.; Cooper, K.R.

    1994-12-31

    This study evaluated the sensitivity of the fathead minnow larvae to 2,3,7,8-TCDD. There are no reported studies that have examined 2,3,7,8-TCDD toxic effects on fathead minnow larvae (0.0017--0.0094 g). One month old fathead minnow larvae were exposed to varying concentrations of [H{sup 3}]2,3,7,8-TCDD for 24h, and then were transferred into clean water. The no-treatment, acetone-control and 2,3,7,8-TCDD exposed larvae were observed for at least 32 days after exposure. Mortality, growth and appearance of a wasting-type syndrome were noted. The tissue dose were based on larvae wet weight. One hundred percent mortality was observed at a tissue dose of 163 ng/g at 32 days. The wasting-type syndrome appeared at day 7 after the 2,3,7,8-TCDD exposure. Statistically significant differences in growth (total length and weight) were observed at tissue doses as low as 20 ng/g. The wasting-type syndrome was observed in all fish by day 20. The 2,3,7,8-TCDD tissue level showing this effect was 44 ng/g. These results suggested that the fathead minnow larvae are more sensitive than the Japanese medaka larvae, and not as sensitive as the lake trout.

  17. Ternary borides Nb7Fe3B8 and Ta7Fe3B8 with Kagome-type iron framework.

    PubMed

    Zheng, Qiang; Gumeniuk, Roman; Borrmann, Horst; Schnelle, Walter; Tsirlin, Alexander A; Rosner, Helge; Burkhardt, Ulrich; Reissner, Michael; Grin, Yuri; Leithe-Jasper, Andreas

    2016-06-21

    Two new ternary borides TM7Fe3B8 (TM = Nb, Ta) were synthesized by high-temperature thermal treatment of samples obtained by arc-melting. This new type of structure with space group P6/mmm, comprises TM slabs containing isolated planar hexagonal [B6] rings and iron centered TM columns in a Kagome type of arrangement. Chemical bonding analysis in Nb7Fe3B8 by means of the electron localizability approach reveals two-center interactions forming the Kagome net of Fe and embedded B, while weaker multicenter bonding present between this net and Nb atoms. Magnetic susceptibility measurements reveal antiferromagnetic order below TN = 240 K for Nb7Fe3B8 and TN = 265 K for Ta7Fe3B8. Small remnant magnetization below 0.01μB per f.u. is observed in the antiferromagnetic state. The bulk nature of the magnetic transistions was confirmed by the hyperfine splitting of the Mössbauer spectra, the sizable anomalies in the specific heat capacity, and the kinks in the resistivity curves. The high-field paramagnetic susceptibilities fitted by the Curie-Weiss law show effective paramagnetic moments μeff≈ 3.1μB/Fe in both compounds. The temperature dependence of the electrical resistivity also reveals metallic character of both compounds. Density functional calculations corroborate the metallic behaviour of both compounds and demonstrate the formation of a sizable local magnetic moment on the Fe-sites. They indicate the presence of both antiferro- and ferrromagnetic interactions.

  18. Fingerprinting 2,3,7,8-tetrachlorodibenzodioxin contamination within the lower Passaic River.

    PubMed

    Quadrini, James D; Ku, Wen; Connolly, John P; Chiavelli, Deborah A; Israelsson, Peter H

    2015-07-01

    The lower Passaic River is an operable unit of the Diamond Alkali Superfund site at 80 and 120 Lister Avenue in Newark, New Jersey, USA. Between 1948 and 1969, the Diamond Shamrock Chemicals Company and its predecessors manufactured chemicals such as pesticides and phenoxy herbicides, including 2,4,5-trichlorophenol, which is a precursor to 2,4,5-trichlorophenoxyacetic acid, one of the primary components used to make the military defoliant Agent Orange. A by-product of this manufacturing process was 2,3,7,8-tetrachlorodibenzodioxin (2,3,7,8-TCDD), and the site is considered the dominant source of 2,3,7,8-TCDD to the lower Passaic River and its environs. Several investigators have identified the ratio of 2,3,7,8-TCDD to total TCDD as a fingerprint for the site source. The present study presents data that establish polychlorinated dibenzodioxin/polychlorinated dibenzofuran (collectively, PCDD/F) congener and homolog fingerprints of soil and sump samples from the site. It then compares those fingerprints to the PCDD/F congener and homolog patterns in lower Passaic River sediments. The similarity of the patterns in lower Passaic River sediments to the site fingerprint indicates the site is the dominant source of the 2,3,7,8-TCDD in sediments within approximately the lower 14 miles of the lower Passaic River, excluding, for the purposes of the present discussion, Newark Bay. In addition, PCDD/F congener data indicate that the ratio of 1,3,7,8-TCDD to 2,3,7,8-TCDD is another marker of the site and corroborates the findings from the other fingerprints. PMID:25726763

  19. Fingerprinting 2,3,7,8-tetrachlorodibenzodioxin contamination within the lower Passaic River

    PubMed Central

    Quadrini, James D; Ku, Wen; Connolly, John P; Chiavelli, Deborah A; Israelsson, Peter H

    2015-01-01

    The lower Passaic River is an operable unit of the Diamond Alkali Superfund site at 80 and 120 Lister Avenue in Newark, New Jersey, USA. Between 1948 and 1969, the Diamond Shamrock Chemicals Company and its predecessors manufactured chemicals such as pesticides and phenoxy herbicides, including 2,4,5-trichlorophenol, which is a precursor to 2,4,5-trichlorophenoxyacetic acid, one of the primary components used to make the military defoliant Agent Orange. A by-product of this manufacturing process was 2,3,7,8-tetrachlorodibenzodioxin (2,3,7,8-TCDD), and the site is considered the dominant source of 2,3,7,8-TCDD to the lower Passaic River and its environs. Several investigators have identified the ratio of 2,3,7,8-TCDD to total TCDD as a fingerprint for the site source. The present study presents data that establish polychlorinated dibenzodioxin/polychlorinated dibenzofuran (collectively, PCDD/F) congener and homolog fingerprints of soil and sump samples from the site. It then compares those fingerprints to the PCDD/F congener and homolog patterns in lower Passaic River sediments. The similarity of the patterns in lower Passaic River sediments to the site fingerprint indicates the site is the dominant source of the 2,3,7,8-TCDD in sediments within approximately the lower 14 miles of the lower Passaic River, excluding, for the purposes of the present discussion, Newark Bay. In addition, PCDD/F congener data indicate that the ratio of 1,3,7,8-TCDD to 2,3,7,8-TCDD is another marker of the site and corroborates the findings from the other fingerprints. Environ Toxicol Chem 2015;34:1485–1498. © 2015 The Authors. Published by SETAC. PMID:25726763

  20. Fingerprinting 2,3,7,8-tetrachlorodibenzodioxin contamination within the lower Passaic River.

    PubMed

    Quadrini, James D; Ku, Wen; Connolly, John P; Chiavelli, Deborah A; Israelsson, Peter H

    2015-07-01

    The lower Passaic River is an operable unit of the Diamond Alkali Superfund site at 80 and 120 Lister Avenue in Newark, New Jersey, USA. Between 1948 and 1969, the Diamond Shamrock Chemicals Company and its predecessors manufactured chemicals such as pesticides and phenoxy herbicides, including 2,4,5-trichlorophenol, which is a precursor to 2,4,5-trichlorophenoxyacetic acid, one of the primary components used to make the military defoliant Agent Orange. A by-product of this manufacturing process was 2,3,7,8-tetrachlorodibenzodioxin (2,3,7,8-TCDD), and the site is considered the dominant source of 2,3,7,8-TCDD to the lower Passaic River and its environs. Several investigators have identified the ratio of 2,3,7,8-TCDD to total TCDD as a fingerprint for the site source. The present study presents data that establish polychlorinated dibenzodioxin/polychlorinated dibenzofuran (collectively, PCDD/F) congener and homolog fingerprints of soil and sump samples from the site. It then compares those fingerprints to the PCDD/F congener and homolog patterns in lower Passaic River sediments. The similarity of the patterns in lower Passaic River sediments to the site fingerprint indicates the site is the dominant source of the 2,3,7,8-TCDD in sediments within approximately the lower 14 miles of the lower Passaic River, excluding, for the purposes of the present discussion, Newark Bay. In addition, PCDD/F congener data indicate that the ratio of 1,3,7,8-TCDD to 2,3,7,8-TCDD is another marker of the site and corroborates the findings from the other fingerprints.

  1. Anti-platelet activity of erythro-(7S,8R)-7-acetoxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan from Myristica fragrans.

    PubMed

    Kang, Jung Won; Min, Byung-Sun; Lee, Jeong-Hyung

    2013-11-01

    Platelets play a critical role in pathogenesis of cardiovascular disorders and strokes. The inhibition of platelet function is beneficial for the treatment and prevention of these diseases. In this study, we investigated the anti-platelet activity of erythro-(7S,8R)-7-acetoxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan (EATN), a neolignan isolated from Myristica fragrans, using human platelets. EATN preferentially inhibited thrombin- and platelet-activating factor (PAF)-induced platelet aggregation without affecting platelet damage in a concentration-dependent manner with IC50 values of 3.2 ± 0.4 and 3.4 ± 0.3 μM, respectively. However, much higher concentrations of EATN were required to inhibit platelet aggregation induced by arachidonic acid. EATN also inhibited thrombin-induced serotonin and ATP release, and thromboxane B2 formation in human platelets. Moreover, EATN caused an increase in cyclic AMP (cAMP) levels and attenuated intracellular Ca(2+) mobilization in thrombin-activated human platelets. Therefore, we conclude that the inhibitory mechanism of EATN on platelet aggregation may increase cAMP levels and subsequently inhibit intracellular Ca(2+) mobilization by interfering with a common signaling pathway rather than by directly inhibiting the binding of thrombin or PAF to their receptors. This is the first report of the anti-platelet activity of EATN isolated from M. fragrans.

  2. Anti-platelet activity of erythro-(7S,8R)-7-acetoxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan from Myristica fragrans.

    PubMed

    Kang, Jung Won; Min, Byung-Sun; Lee, Jeong-Hyung

    2013-11-01

    Platelets play a critical role in pathogenesis of cardiovascular disorders and strokes. The inhibition of platelet function is beneficial for the treatment and prevention of these diseases. In this study, we investigated the anti-platelet activity of erythro-(7S,8R)-7-acetoxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan (EATN), a neolignan isolated from Myristica fragrans, using human platelets. EATN preferentially inhibited thrombin- and platelet-activating factor (PAF)-induced platelet aggregation without affecting platelet damage in a concentration-dependent manner with IC50 values of 3.2 ± 0.4 and 3.4 ± 0.3 μM, respectively. However, much higher concentrations of EATN were required to inhibit platelet aggregation induced by arachidonic acid. EATN also inhibited thrombin-induced serotonin and ATP release, and thromboxane B2 formation in human platelets. Moreover, EATN caused an increase in cyclic AMP (cAMP) levels and attenuated intracellular Ca(2+) mobilization in thrombin-activated human platelets. Therefore, we conclude that the inhibitory mechanism of EATN on platelet aggregation may increase cAMP levels and subsequently inhibit intracellular Ca(2+) mobilization by interfering with a common signaling pathway rather than by directly inhibiting the binding of thrombin or PAF to their receptors. This is the first report of the anti-platelet activity of EATN isolated from M. fragrans. PMID:23296979

  3. Gridded atmospheric emission inventory of 2,3,7,8-TCDD in China

    NASA Astrophysics Data System (ADS)

    Huang, Tao; Tian, Chongguo; Zhang, Kai; Gao, Hong; Li, Yi-Fan; Ma, Jianmin

    2015-05-01

    Establishment of the dioxins emission inventory has been considered as a crucial step toward risk assessment and elimination of dioxins contaminations. Based on a total dioxin emission inventory in China from different emission categories in 2004, this study created a gridded emission inventory of 2,3,7,8-TCDD, the most toxic congener in dioxins, in China in 2009 with a 1/4° longitude by 1/4° latitude resolution. It was estimated that annually total 371 ± 53 g (average ± standard deviation) of 2,3,7,8-TCDD was released into the atmosphere in 2009 over China, increasing approximately by 37% compared with its emission in 2004. Differing from most developed countries where municipal waste incinerations were regarded as a major atmospheric emission source, in China ferrous and non-ferrous metal production made the largest contribution to 2,3,7,8-TCDD air emission (138 ± 16 g), followed by waste incineration (109 ± 12 g), power and heating generation (62 ± 9 g), and production of mineral products (47 ± 8 g). The rest of sources contributed approximately 3% to the total 2,3,7,8-TCDD emission in 2009. Iron and steel industries are mainly located in Beijing-Tianjin-Hebei (BTH) and Yangtze River Delta (YRD) regions, whereas waste incinerators are mainly located in Pearl River Delta (PRD) region. Higher 2,3,7,8-TCDD emissions were found in these three regions. While the BTH, YRD, and PRD accounted for only about 4% of total land area of China, they contributed approximately 14%, 15%, and 5% to the total 2,3,7,8-TCDD emission in 2009 in China, respectively.

  4. The interactions of 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD) and 6-methyl-1,3,8-trichlorodibenzofuran (MCDF) in TCDD-induced porphyria

    SciTech Connect

    Yao, Cheng Catsby.

    1989-01-01

    Halogenated aryl hydrocarbon(HAH)-induced porphyria is caused by alteration of porphyrin metabolism and results in the accumulation of hepatic and urinary porphyrins. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (75 {mu}/kg) caused significant increases of hepatic porphyrin levels in C57BL/6 male, female and ovariectomized female, and C57BL/10 male mice 3 weeks after treatment. In contrast, 6-methyl-1,3,8-trichlorodibenzofuran (MCDF) was inactive at a dose of 750 {mu}mol/kg. Cotreatment with MCDF (750 {mu}mol/kg) and 2,3,7,8-TCDD (75 {mu}g/kg) resulted in partial antagonism of 2,3,7,8-TCDD-induced porphyrin accumulation in female but not in male mice. In female C57BL/6 mice, 2,3,7,8-TCDD-induced porphyria was accompanied by the induction of hepatic microsomal aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) activities and the inhibition of uroporphyrinogen decarboxylase (UROD) activity. MCDF (750 {mu}mol/kg) did not significantly affect these enzyme activities. In coadministration studies, MCDF partially antagonized 2,3,7,8-TCDD-induced hepatic porphyrin accumulation but did not affect the activities of hepatic AHH, EROD or UROD. These results demonstrate that the induction of the monooxygenase enzyme activities and the inhibition of UROD activity by 2,3,7,8-TCDD and the development of porphyria are not coordinately regulated in C57BL/6 female mice. In cultured chick embryo hepatocytes, 2,3,7,8-TCDD caused a significant increase in porphyrin levels and induced AHH and EROD activities. MCDF and Aroclor 1254 partially antagonized the 2,3,7,8-TCDD induced AHH and EROD activities but not the porphyrin accumulation.

  5. Fragrance material review on 1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (OTNE).

    PubMed

    Scognamiglio, J; Letizia, C S; Politano, V T; Api, A M

    2013-12-01

    A toxicologic and dermatologic review of 1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (OTNE) when used as a fragrance ingredient is presented. OTNE is a member of the fragrance structural group Alkyl Cyclic Ketones. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for OTNE were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, phototoxicity, photoallergy, toxicokinetics, repeated dose, reproductive toxicity, and genotoxicity data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (2013) for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances.

  6. Engine component improvement: Performance improvement, JT9D-7 3.8 AR fan

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1980-01-01

    A redesigned, fuel efficient fan for the JT9D-7 engine was tested. Tests were conducted to determine the effect of the 3.8 AR fan on performance, stability, operational characteristics, and noise of the JT9D-7 engine relative to the current 4.6 AR Bill-of-Material fan. The 3.8 AR fan provides increased fan efficiency due to a more advanced blade airfoil with increased chord, eliminating one part span shroud and reducing the number of fan blades and fan exit guide vanes. Engine testing at simulated cruise conditions demonstrated the predicted 1.3 percent improvement in specific fuel consumption with the redesigned 3.8 AR fan. Flight testing and sea level stand engine testing demonstrated exhaust gas temperature margins, fan and low pressure compressor stability, operational suitability, and noise levels comparable to the Bill-of-Material fan.

  7. Nqrs Data for C8H7ClN2O3 (Subst. No. 1078)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C8H7ClN2O3 (Subst. No. 1078)

  8. HEALTH RISK ASSESSMENT APPROACH FOR 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (1985)

    EPA Science Inventory

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is one of the most toxic and environmentally stable pollutants. In addition to various toxic effects, TCDD has been found to cause teratogenic, fetocidal, reproductive and carcinogenic effects in animals. In humans it adversely affects v...

  9. ANALYSIS OF 2,3,7,8-TCDD TUMOR PROMOTION ACTIVITY AND ITS RELATIONSHIP TO CANCER

    EPA Science Inventory

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has a high estimated cancer potency in animals which has been reasoned to imply that TCDD might be carcinogenic to man. The animal cancer data show that TCDD can act in a solitary manner causing tumors without the participation of other ...

  10. SORPTION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN FROM WATER BY SURFACE SOILS

    EPA Science Inventory

    The sorption of l4C-labeled 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD) from water by two uncontaminated surface soils from the Times Beach, MO, area was evalu- ated by using batch shake testing. Sorption isotherm plots for the soil with the lower fraction organic carbon (f,) wer...

  11. Hexachlorodibenzo-p-dioxin (HxCDD), mixture of 1,2,3,6,7,8-HxCDD and 1,2,3,7,8,9-HxCDD

    Integrated Risk Information System (IRIS)

    Hexachlorodibenzo - p - dioxin ( HxCDD ) , mixture of 1,2,3,6,7,8 - HxCDD and 1,2,3,7,8,9 - HxCDD ; CASRN 57653 - 85 - 7 and 19408 - 74 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in

  12. Is 2,3,7,8-TCDD (dioxin) a carcinogen for humans

    SciTech Connect

    Ayres, S.M.; Webb, K.B.; Evans, R.G.; Mikes, J.

    1985-10-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has suddenly become the focal point of controversy over the relationship of chemical waste to human health. Specific concern exists regarding its potential association with human malignancy. Subcellular, cellular, and whole-animal experiments suggest that TCDD exerts much of its activity by inducing enzymes that protect the intact organism from the assault of environmental contamination. TCDD is a potent inducer of aryl hydrocarbon hydroxylase, although wide variations between species do exist. Conventional tests for mutagenicity have produced conflicting results. Animal experiments have shown the development of tumors following chronic low level ingestion of TCDD. The human evidence regarding the potential carcinogencity of TCDD comes from occupational, military and environmental exposures. Several studies have come out of Sweden suggesting an association between sarcoma and exposure to herbicides. Although there is little solid evidence that 2,3,7,8-TCDD produces substantial chronic disability or premature death in man, a significant body of experimental evidence for its carcinogenicity makes it likely that a small number of human malignancies may be due to its action. Since 2,3,7,8-TCDD is an unwanted contaminant it could be eliminated with little measurable consequence.

  13. Is 2,3,7,8-TCDD (dioxin) a carcinogen for humans?

    PubMed Central

    Ayres, S M; Webb, K B; Evans, R G; Mikes, J

    1985-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has suddenly become the focal point of controversy over the relationship of chemical waste to human health. Specific concern exists regarding its potential association with human malignancy. Subcellular, cellular, and whole-animal experiments suggest that TCDD exerts much of its activity by inducing enzymes that protect the intact organism from the assault of environmental contamination. TCDD is a potent inducer of aryl hydrocarbon hydroxylase, although wide variations between species do exist. Conventional tests for mutagenicity have produced conflicting results. Animal experiments have shown the development of tumors following chronic low level ingestion of TCDD. The human evidence regarding the potential carcinogencity of TCDD comes from occupational, military and environmental exposures. Several studies have come out of Sweden suggesting an association between sarcoma and exposure to herbicides. Although there is little solid evidence that 2,3,7,8-TCDD produces substantial chronic disability or premature death in man, a significant body of experimental evidence for its carcinogenicity makes it likely that a small number of human malignancies may be due to its action. Since 2,3,7,8-TCDD is an unwanted contaminant it could be eliminated with little measurable consequence. PMID:3910419

  14. Teratogenicity of 2,3,7,8-tetrachlorodibenzofuran in the mouse

    SciTech Connect

    Hassoun, E.; d'Argy, R.; Dencker, L.

    1984-01-01

    2,3,7,8-Tetrachlorodibenzofuran (TCDBF) was administered in single doses (0.1-0.8 mg/kg body weight) intraperitoneally to pregnant C57BL mice on d 10, 11, 12, or 13 of gestation. A dose-dependent increase was observed in the frequency of fetal resorptions and fetal death, especially in the earlier stages (d 10-11). Cleft palate and hydronephrosis as well appeared in a dose-dependent manner, with a peak in sensitivity after administration on d 11-12. TCDBF given at a dose level of 0.1 mg/kg body weight on d 12 of gestation (only dose- and stage-tested) produced a marked thymic hypoplasia as well. A few cases of general hydrops occurred. The pattern of malformations and time of sensitivity corresponded well to that observed earlier after administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; ED50 approx. = 25 ..mu..g/kg) and 3,3',4,4'-tetrachloroazoxybenzene (TCAOB; ED50 approx. = 6 mg/kg), two congeners of TCDBF, indicating common mechanisms of action of this family of compounds. Ornithine decarboxylase (ODC) is an important enzyme in cell proliferation and growth with a high activity in embryonic tissues. Liver ODC activity has previously been found to be stimulated by TCDD in weanling mice. However, this enzyme was not found to be stimulated in fetal and placental tissues, but slightly in maternal kidney after treatment with TCDBF in teratogenic doses. It is possible that the ODC activity increases under certain conditions only, on administration of TCDD and its congeners. 40 references, 3 tables, 3 figures.

  15. Ground states at the filling factors ν = 7 / 3 and 8 / 3 in the second Landau level

    NASA Astrophysics Data System (ADS)

    Ito, Toru; Shibata, Naokazu; Nomura, Kentaro; Department of Physics, Tohoku University Team

    2013-03-01

    The Laughlin state successfully describe the fractional quantum Hall state at ν = 1 / 3 in the lowest Landau level. However, it is known that the Laughlin wavefunction has little overlap with the ground state wavefunction at ν = 7 / 3 in the second Landau level. The ground states at ν = 7 / 3 and 8 / 3 are still unknown.To determine the ground states at these fillings, we use the exact diagonalization method and density-matrix renormalization group (DMRG) method. We calculate overlaps between the ground state and the trial wavefunctions, the ground state energies, and the ground-state pair-correlation functions. We find that the ground state wavefunction at ν = 8 / 3 have very high overlap between the parafermion state, and the ground state energy of the parafermion state is lower than that of the Laughlin state. Further, the short-range structures of pair-correlation functions are significantly different from that of the Lauglin state.From these results, we consider that the parafermion state is a strong candidate of the ground state at ν = 7 / 3 and ν = 8 / 3 .

  16. Water solubility of 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Marple, L.; Brunck, R.; Throop, L.

    1986-02-01

    Vacuum deposition of a solid film onto a glass surface and equilibrium on this film with water are the basis of a method that was used to measure the water solubility of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Films of both /sup 14/C-radiolabeled and unlabeled dioxin were prepared so that solubilized material could be measured by radioactivity as well as by capillary GC/LRMS techniques. The averages of solubility values for radiolabeled and unlabeled dioxin were 3.9 x 10/sup -11/ M (12.5 parts per trillion) and 6.0 x 10/sup -11/ M (19.3 parts per trillion), respectively. The solubility values lie within the values predicted from Yalkowsky's K/sub ow/-solubility equation of best fit for chlorinated hydrocarbons and the available estimates for the octanol-water partition coefficient, K/sub ow/. 11 references, 2 tables.

  17. High antiallergic activity of 5,6,4'-trihydroxy-7,8,3'-trimethoxyflavone and 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone from eau de cologne mint (Mentha×piperita citrata).

    PubMed

    Sato, Akihiko; Tamura, Hirotoshi

    2015-04-01

    The following compounds with higher antiallergic activities were isolated from eau de cologne mint leaves: 5,6,4'-trihydroxy-7,8-dimethoxyflavone (6), 5,6,4'-trihydroxy-7,8,3'-trimethoxyflavone (7), 5,6-dihydroxy-7,3',4'-trimethoxyflavone (8), 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone (9), and 5,6-dihydroxy-7,8,4'-trimethoxyflavone (10). The IC50 values of compounds 6-10 against RBL-2H3 cells were 6.7, 2.4, 5.6, 3.0, and 6.1μM. Compounds 7 and 9 (IC50 2.4μM and 3.0μM) had the highest antiallergic activities among the flavonoids previously reported. The amounts of 7, 9, and 10 isolated were fairly high, at 177.7mg/kg, 278.0mg/kg, and 179.7mg/kg in the mint, respectively. LD5 value (index of toxicity) and LD5/IC50 ratio of 7 and 9 indicate that the safety is greater than that of luteolin, a typical antiallergic substance. The extract containing powerful antiallergic flavones, 6-10 with higher hydrophobicity could be selectively separated from the extract containing luteolin and other flavonoid glycosides by partition with dichloromethane and water. Therefore, compounds 7 and 9 in mint, and the dichloromethane extract would be the most potent and preventive resources against type I allergy.

  18. Metabolism and disposition of 2,3,7,8-tetrachlorodibenzo-p-dioxin in guinea pigs

    SciTech Connect

    Olson, J.R.

    1986-09-15

    Marked interspecies variability exists in the acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), with the guinea pig being the mammalian species most sensitive to the acute toxicity of TCDD. The metabolism and disposition of TCDD was investigated in guinea pigs for 45 days following a single exposure to purified (/sup 3/H)TCDD (0.56 microgram/kg, ip). Guinea pigs included in the toxicokinetic study gained body weight, maintained a normal relative body composition, and exhibited no gross signs of toxicity during the 45-day study. Approximately 36% of the dose of TCDD-derived /sup 3/H remained in the adipose tissue at 45 days following exposure to (/sup 3/H)TCDD, while the liver, pelt, and skeletal muscle and carcass each contained about 7% of the administered dose. Although most of the TCDD-derived radioactivity in liver, kidney, perirenal adipose tissue, and skeletal muscle represented unchanged TCDD, from 4 to 28% of the /sup 3/H was associated with metabolites of TCDD. This unexpected finding suggests that TCDD metabolites are not efficiently excreted from guinea pigs. The urinary and fecal excretion of TCDD-derived radioactivity followed apparent first-order kinetics, with an elimination half-life of 93.7 +/- 15.5 days (mean +/- SD). HPLC analysis of urine and bile from (/sup 3/H)TCDD-treated guinea pigs showed that all of the radioactivity represented metabolites of TCDD, indicating that these routes of elimination are dependent on prior metabolism of TCDD. However, 70 to 90% of the radioactivity in fecal samples was found to represent unmetabolized TCDD throughout the 45-day excretion study. The presence of TCDD in feces and its absence in bile suggest that the fecal excretion of unchanged TCDD resulted from the direct intestinal elimination of the lipophilic toxin.

  19. 8-(3-chloro-4-methoxybenzyl)-8H-pyrido[2,3-d]pyrimidin-7-one derivatives as potent and selective phosphodiesterase 5 inhibitors.

    PubMed

    Sakamoto, Toshiaki; Koga, Yuichi; Hikota, Masataka; Matsuki, Kenji; Mochida, Hideki; Kikkawa, Kohei; Fujishige, Kotomi; Kotera, Jun; Omori, Kenji; Morimoto, Hiroshi; Yamada, Koichiro

    2015-04-01

    A novel series of highly selective phosphodiesterase 5 (PDE5) inhibitors was found. 8H-Pyrido[2,3-d]pyrimidin-7-one derivatives bearing an (S)-2-(hydroxymethyl)pyrrolidin-1-yl group at the 2-position and a 3-chloro-4-methoxybenzyl group at the 8-position exhibited potent PDE5 inhibitory activities and high PDE5 selectivity over PDE6. Among the synthesized compounds, the 5-methyl analogue (5b) showed the most potent relaxant effect on isolated rabbit corpus cavernosum with an EC30 value of 0.85 nM. PMID:25754491

  20. 3-Hy-droxy-8-oxo-3-nor-methyl-chamigrane-2,7-peroxide.

    PubMed

    Liu, Dongze

    2010-01-01

    In the title compound, C(14)H(22)O(4) (systematic name: 9-hy-droxy-1,5,5-trimethyl-1,8-epidi-oxy-spiro-[5.5]decan-2-one), which was isolated from the fermentation broth of Steccherinum ochraceum, the two six-membered rings adopt chair conformations and are bridged by a peroxide group. The hy-droxy H atom forms a three-centre cyclic inter-molecular O-H⋯(O,O') hydrogen-bonding inter-action with a peroxide and a carbonyl O-atom acceptor, forming [100] chains.

  1. Radiolysis of 2,3,7,8-tetrachlorodibenzo- p-dioxin in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Mamedov, Kh. F.; Aliev, A. G.; Mamedova, N. A.; Badalova, A. R.

    2015-09-01

    The conversion of 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD) in diluted aqueous solutions at different absorbed doses of ionizing radiation using the 60Co source is studied. The radiochemical yield of TCDD conversion is (0.3-1.5) × 10-5 molecules/100 eV for solutions with 0.2-2 μg/L TCDD in open cells and 2.4 × 10-5 molecules/100 eV for air-sparged 2 μg/L TCDD solutions. It is demonstrated that the absorbed dose of ionizing radiation (25 kGy) lowers the TCDD concentration in oxygen-containing aqueous solutions virtually to zero.

  2. Effects of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane doping on diketopyrrolopyrrole-based, low crystalline, high mobility polymeric semiconductor

    SciTech Connect

    Yoon, Seongwon; Cho, Jangwhan; Chung, Dae Sung; Lee, Han-Koo; Park, Sungmin; Son, Hae Jung

    2015-09-28

    The effects of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) doping on diketopyrrolo-pyrrole-based polymeric semiconductors in terms of charge transport behavior and structural ordering are systematically investigated. Although the energy level offset between the polymeric semiconductor and the F4TCNQ acceptor was not particularly large, ultraviolet photoelectron spectroscopy analyses revealed that a low doping ratio of 1 wt. % is sufficient to tune the energy distance between the Fermi level and the HOMO level, reaching saturation at roughly 5 wt. %, which is further confirmed by the depletion mode measurements of field effect transistors (FETs). Structural analyses using grazing-incidence X-ray diffraction (GIXD) show that the overall degree of edge-on orientation is disturbed by the addition of dopants, with significant influence appearing at high doping ratios (>3 wt. %). The calculated charge carrier mobility from accumulation mode measurements of FETs showed a maximum value of 2 cm{sup 2}/V·s at the optimized doping ratio of 1%, enabled by additional holes in the channel region, which results in a roughly 40% increase relative to the undoped device. Further increases in the doping ratio, however, resulted in worse FET performance, which can be attributed to structural deformation. This result suggests that the electrochemical doping method can be also applied to donor-acceptor copolymers to further enhance their charge transport characteristics, once the optimized doping condition has been established.

  3. Immunological markers among workers exposed to 2,3,7,8- tetrachlorodibenzo-p-dioxin

    PubMed Central

    Halperin, W.; Vogt, R.; Sweeney, M. H.; Shopp, G.; Fingerhut, M.; Petersen, M.

    1998-01-01

    OBJECTIVES: To examine the association of immune cell number and function with occupational exposure to substances contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). METHODS: A cross sectional medical survey. The exposed participants were employed at two chemical plants between 1951 and 1972 in the manufacture of 2,4,5- trichlorophenate and its derivatives. The reference group consisted of people with no occupational exposure to phenoxy herbicides who lived within the communities of the workers. Data from a total of 259 workers and 243 unexposed referents were included in the analysis of immune function. Laboratory tests for immune status included enumeration of circulating leukocyte and lymphocyte populations, proliferative responses of circulating lymphocytes to mitogens and antigens, and serum concentrations of the major immunoglobulins and complement factor C3. RESULTS: The workers had substantial exposure to substances contaminated with TCDD, as indicated by a lipid adjusted mean serum TCDD concentration of 229 ppt compared with a mean of 6 ppt in the unexposed referents. Workers were divided into categories based on their serum TCDD concentration. For all categories except the lowest, with values of serum TCDD comparable with the unexposed referents, there were increased odds of having lower counts of CD26 cells (activated T cells) (odds ratio (OR) 1.0, 95% confidence interval (95% CI) 0.5 to 1.8 for TCDD < 20 ppt; OR 1.6, 95% CI 0.8 to 3.2 for TCDD 20- 51 ppt; OR 2.7, 95% CI 1.4 to 5.1 for TCDD 52-125 ppt; OR 2.6, 95% CI 1.4 to 4.9 for TCDD 125-297 ppt; OR 2.4, 95% CI 1.3 to 4.6 for TCDD 298- 3389 ppt). A less consistent finding was decreased spontaneous proliferation of cultured lymphocytes. However, increases were found in proliferation of lymphocytes in response to concanavalin and pokeweed in workers in the high TCDD category. Age, cigarette smoking, and alcohol were significant predictors of several immunological outcomes. CONCLUSIONS

  4. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and long term immunologic memory.

    PubMed

    Sherr, David H

    2004-06-01

    The highlighted article by B. Paige Lawrence and Beth Vorderstrasse addresses an oft forgotten aspect of immunotoxicity, the effects of environmental toxins on immunologic memory. Here, the authors take a step towards filling that information gap by evaluating the effects of a prototypic environmental toxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on memory responses to a real-world pathogen, influenza A virus, presented to an animal model in a physiologically relevant manner. Multiple outcomes are evaluated, the vast majority of which suggest important and long-term TCDD-induced changes in the immune system after both primary and secondary exposure to this pathogen. The implications of these studies with regard to the immuno-competence of TCDD-exposed individuals are far reaching.

  5. Biomagnification of bioassay derived 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents

    USGS Publications Warehouse

    Jones, P.D.; Ankley, G.T.; Best, D. A.; Crawford, R.; DeGalan, N.; Giesy, J.P.; Kubiak, T.J.; Ludwig, J. P.; Newsted, J.L.; Tillitt, D. E.; Verbrugge, D.A.

    1993-01-01

    In recent years contamination of the Great Lakes ecosystem with planar chlorinated hydrocarbons (PCHs) has attracted considerable concern due to their known reproductive and teratogenic effects. The H4IIE bioassay has been standardized as a means of measuring the biological potency of a PCH mixture as 2,3,7,8-tetrachloro-p-dibenzodioxin equivalents (TCDD-EQ). Using this bioassay we have investigated the biomagnification of TCDD-EQ in a semi-closed ecosystem. The biomagnification of TCDD-EQ is demonstrated and results indicate that the food chain is the major pathway for TCDD-EQ through this ecosystem. The H4IIE assay system is demonstrated to be a viable integrative measure of the total concentration of TCDD-EQ in different trophic levels.

  6. Proposed occupational exposure limit for 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Leung, H.W.; Murray, F.J.; Paustenbach, D.J.

    1988-09-01

    One contaminant produced unintentionally during the manufacture of chlorophenols and phenoxy herbicides is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The resulting TCDD-containing wastes have been detected at many hazardous waste sites which in recent years have been in the process of remediation. Concerns about worker exposure to TCDD-contaminated soil (dust) during remediation of hazardous waste sites have produced a need for an occupational exposure limit (OEL) for TCDD. The animal toxicology data and human experience with TCDD are reviewed, and an occupational exposure limit for TCDD is proposed. The animal data support risk estimations which are based on TCDD as a nongenotoxic carcinogen. Studies on human populations have failed to demonstrate clearly any significant long-term health effects at levels to which humans have been exposed. The data indicate that an 8-hr time-weighted average limit of 2 ng/m3 is appropriate, and the associated risk would be consistent with other carcinogens at their corresponding OELs. A preliminary OEL of 0.2 ng/m3 (200 pg/m3) is recommended, however, in light of other sources of exposure because of TCDD's ubiquitousness in the environment, its unclear mechanism of action, and its rather long biological half-life in humans. This limit provides an ample margin of safety to prevent chloracne following repeated, acute exposure, and it addresses those chronic effects of TCDD observed in animal studies as well as those observed after accidental human exposure. The resulting body burden caused by chronic exposure to TCDD at the proposed OEL is examined. Its toxicological significance is compared with human tissue data and with other similarly persistent chemicals. 74 references.

  7. 33.8 Tesla with a YBa2Cu3O7-x Superconducting Test Coil

    NASA Astrophysics Data System (ADS)

    Markiewicz, W. D.; Weijers, H. W.; Noyes, P. D.; Trociewitz, U. P.; Pickard, K. W.; Sheppard, W. R.; Jaroszynski, J. J.; Xu, A.; Larbalestier, D. C.; Hazelton, D. W.

    2010-04-01

    A small coil was made and tested for the purpose of magnet technology development for YBa2Cu3O7-x (YBCO) high field coils. The coil has a winding inner diameter of 24 mm, outer diameter of 36 mm, and length of 46 mm in a pancake wound construction of 5 double pancakes. The YBCO conductor is SuperPower SCS4050 with 2×20 μm of copper stabilizer. The coil was tested in the high field user facility of the NHMFL in a 31 T background field magnet. At this background field, the coil was operated to a current of 325 A and produced a field increment of 2.8 T for a record total field of 33.8 T. The average current density in the windings at full current was very high at 446 A/mm2. The test was complicated by the accumulation of trapped helium gas about the coil due to the diamagnetic effect of helium at high field. Even though the coil operated at elevated temperature during the high field test, the coil performance was limited by mechanical degradation and not a critical current limit.

  8. Drinking-water criteria document for 2,3,7,8-tetrachlorodibenzo-p-dioxin. Draft report

    SciTech Connect

    Not Available

    1988-04-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) is one of the most toxic and environmentally stable tricyclic aromatic compounds belonging to chlorinated dibenzo-p-dioxins. 2,3,7,8-TCDD has been demonstrated to be teratogenic in rats, mice and rabbits, and feticidal in monkeys. The major toxic signs and terata observed were cleft palate in mice, edema, hemorrhage, and kidney anomalies in rats and extra ribs in rabbits. Some epidemiological studies have indicated a possible teratogenic effect in humans, but the evidence is not sufficient to reach a firm conclusion.

  9. Genotoxicity tests with 6-acetyl-1,1,2,4,4,7-hexamethyltetraline and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyr an.

    PubMed

    Api, A M; San, R H

    1999-10-29

    6-Acetyl-1,1,2,4,4,7-hexamethyltetraline (AHTN) and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-ben zopyran (HHCB), synthetic fragrance ingredients, were evaluated for potential genotoxicity in a battery of short-term tests. Salmonella typhimurium/Escherichia coli plate incorporation and liquid preincubation assays were conducted on AHTN using tester strains TA97, TA98, TA100, TA102, TA1535, TA1537 and WP2 uvrA +/- S9 activation at doses from 8 to 5000 micrograms/plate. The plate incorporation mutagenicity assay was conducted on HHCB using tester strains TA98, TA100, TA1535, TA1537, TA1538 and WP2 uvrA +/- S9 activation at doses from 10 to 5000 micrograms/plate. An in vitro cytogenetics assay in Chinese hamster ovary (CHO) cells was conducted with AHTN and HHCB at three concentrations each with +/- S9 activation. In the non-activated study, the exposure/harvest periods were 4/20-, 20/20- and 44/44-h. In the S9 activated study, the exposure/harvest periods were 4/20- and 4/44-h. In vitro unscheduled DNA synthesis (UDS) assays were conducted in primary rat hepatocytes at concentrations between 0.15 and 50 micrograms/ml for AHTN and HHCB. In vivo mouse micronucleus assays were conducted with high doses of 1600 mg AHTN/kg and of 1500 mg HHCB/kg in corn oil. No positive responses were observed in any of the tests with HHCB. With AHTN, no positive responses were observed except for cells with structural aberrations in the in vitro cytogenetics assay in CHO cells with S9 activation at the treatment/harvest time of 4/20 h. In initial studies with AHTN, the high dose of 7.8 micrograms/ml showed 0.5% aberrant cells, with the mitotic index at 41% relative to vehicle control and cell growth inhibition in the range of 25-50%. Thus the genotoxicity findings with AHTN were limited to this one positive response; all other genotoxicity tests with AHTN were considered as negative. In particular, the negative finding in the in vivo assay supports AHTN as not likely

  10. A comparative study of Li8NaV3(P2O7)3(PO4)2 and Li9V3(P2O7)3(PO4)2: Synthesis, structure and electrochemical properties

    NASA Astrophysics Data System (ADS)

    Kuang, Quan; Zhao, Yanming; Dong, Youzhong; Fan, Qinghua; Lin, Xinghao; Liu, Xudong

    2016-02-01

    The energy-density improvement for cathode materials by using the method of occupying the Li site with the lowest formation enthalpy was first presented, and successfully applied to Li9V3(P2O7)3(PO4)2. Herein, the synthesis, structure and electrochemical properties (including both Li extraction and intercalation) of mixed alkali-ion phosphate Li8NaV3(P2O7)3(PO4)2 were comprehensively studied, and compared with its isologue Li9V3(P2O7)3(PO4)2. Both Li8NaV3(P2O7)3(PO4)2 and Li9V3(P2O7)3(PO4)2 were synthesized via an original two-step method for the first time. The sintering temperature of Li8NaV3(P2O7)3(PO4)2 (650 °C) was much lower than that of Li9V3(P2O7)3(PO4)2 (750 °C). The Rietveld structure refinement indicated that Na ions occupied the Li1(2b) site of Li9V3(P2O7)3(PO4)2 as expected, and Li8NaV3(P2O7)3(PO4)2 showed a single charge plateau at 4.4 V vs. Li in the 1st cycle. However, the Na ions migrated from Li1(2b) site after the initial cycle, and the charge plateau at 3.7 V vs. Li reappeared. On the other hand, both Li9V3(P2O7)3(PO4)2 and Li8NaV3(P2O7)3(PO4)2 can deliver a high reversible capacity (∼200 mAh g-1), and reveal excellent cycle and rate performance in 3.0-0.05 V vs. Li. The gentle structure changes along with abundant Li intercalation into the bulks suggested that Li9V3(P2O7)3(PO4)2 and Li8NaV3(P2O7)3(PO4)2 were also promising anode materials for Li-ion batteries.

  11. Production and dechlorination of 2,3,7,8-tetrachlorodibenzo-p-dioxin in historically-contaminated estuarine sediments

    SciTech Connect

    Albrecht, I.D.; Barkovskii, A.L.; Adriaens, P.

    1999-03-01

    Polychlorinated dibenzo-p-dioxins (PCDD) are ubiquitous and considered to be unreactive to biotic and abiotic transformation processes. Here the authors demonstrate that sediment-associated 2,3,7,8-substituted dioxin residues in general, and 2,3,7,8-TCDD in particular, are in a state of flux, as they are produced from peri-dechlorination of octaCDD, and further laterally dechlorinated in 2-MCDD. This reaction can be stimulated in the presence of organic acids, 2-monobromodibenzo-p-dioxin (2-MBDD) and hydrogen, which result in the production of HpCDD, 2,3,7,8-TCDD, and 2-MCDD, respectively. The results indicate that dechlorination of 2,3,7,8-TCDD is not likely a rate-limiting step in the hydrogen-stimulated reaction, which presents a potential strategy to decontaminate dioxin-contaminated environments.

  12. Oxidative stress in lake sturgeon orally exposed to 2,3,7,8-tetrachlorodibenzofuran

    SciTech Connect

    Palace, V.P.; Dick, T.A.; Brown, S.B.; Baron, C.L.; Klaverkamp, J.F. |

    1994-12-31

    Juvenile lake sturgeon were orally dosed with gelatin containing nominal concentrations of 0, 0.16 or 1.6 ng 2,3,7,8-tetrachlorodibenzofuran (TCDF)/Kg fish weight. Liver, kidney and blood were collected 10 and 27 days after exposure. Phase 1 (mixed function oxidase MFO) and Phase 2 (glucuronyltransferase) enzyme activities were determined in liver. In addition, concentrations of nonenzymatic (ascorbic acid, tocopherol, retinoids) and enzymatic (superoxide dismutase, catalase, glutathione peroxidase) antioxidant parameters were quantified in liver and kidney. TCDF concentrations were elevated in liver and kidney of both dose groups at 10 and 27 days. However, lower tissue concentrations of TCDF at 27 days compared with 10 day exposures, as well as the presence of polar metabolites in bile, suggest rapid metabolism and clearance of the contaminant. Phase 1 and Phase 2 enzyme activities were induced in a dose dependent manner with activities at the two sample periods reflecting the different TCDF concentrations. Indicators of oxidative stress responded similarly.

  13. Cancer mortality in workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Fingerhut, M.A.; Halperin, W.E.; Marlow, D.A.; Piacitelli, L.A.; Honchar, P.A.; Sweeney, M.H.; Greife, A.L.; Dill, P.A.; Steenland, K.; Suruda, A.J. )

    1991-01-24

    In both animal and epidemiologic studies, exposure to dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, or TCDD) has been associated with an increased risk of cancer. We conducted a retrospective cohort study of mortality among the 5172 workers at 12 plants in the United States that produced chemicals contaminated with TCDD. Occupational exposure was documented by reviewing job descriptions and by measuring TCDD in serum from a sample of 253 workers. Causes of death were taken from death certificates. Mortality from several cancers previously associated with TCDD (stomach, liver, and nasal cancers, Hodgkin's disease, and non-Hodgkin's lymphoma) was not significantly elevated in this cohort. Mortality from soft-tissue sarcoma was increased, but not significantly (4 deaths; standardized mortality ratio (SMR), 338; 95 percent confidence interval, 92 to 865). In the subcohort of 1520 workers with greater than or equal to 1 year of exposure and greater than or equal to 20 years of latency, however, mortality was significantly increased for soft-tissue sarcoma (3 deaths; SMR, 922; 95 percent confidence interval, 190 to 2695) and for cancers of the respiratory system (SMR, 142; 95 percent confidence interval, 103 to 192). Mortality from all cancers combined was slightly but significantly elevated in the overall cohort (SMR, 115; 95 percent confidence interval, 102 to 130) and was higher in the subcohort with greater than or equal to 1 year of exposure and greater than or equal to 20 years of latency (SMR, 146; 95 percent confidence interval, 121 to 176). This study of mortality among workers with occupational exposure to TCDD does not confirm the high relative risks reported for many cancers in previous studies. Conclusions about an increase in the risk of soft-tissue sarcoma are limited by small numbers and misclassification on death certificates.

  14. Transcriptional profiling of rat hypothalamus response to 2,3,7,8-tetrachlorodibenzo-ρ-dioxin.

    PubMed

    Houlahan, Kathleen E; Prokopec, Stephenie D; Moffat, Ivy D; Lindén, Jere; Lensu, Sanna; Okey, Allan B; Pohjanvirta, Raimo; Boutros, Paul C

    2015-02-01

    In some mammals, halogenated aromatic hydrocarbon (HAH) exposure causes wasting syndrome, defined as significant weight loss associated with lethal outcomes. The most potent HAH in causing wasting is 2,3,7,8-tetrachlorodibenzo-ρ-dioxin (TCDD), which exerts its toxic effects through the aryl hydrocarbon receptor (AHR). Since TCDD toxicity is thought to predominantly arise from dysregulation of AHR-transcribed genes, it was hypothesized that wasting syndrome is a result of to TCDD-induced dysregulation of genes involved in regulation of food-intake. As the hypothalamus is the central nervous systems' regulatory center for food-intake and energy balance. Therefore, mRNA abundances in hypothalamic tissue from two rat strains with widely differing sensitivities to TCDD-induced wasting syndrome: TCDD-sensitive Long-Evans rats and TCDD-resistant Han/Wistar rats, 23h after exposure to TCDD (100μg/kg) or corn oil vehicle. TCDD exposure caused minimal transcriptional dysregulation in the hypothalamus, with only 6 genes significantly altered in Long-Evans rats and 15 genes in Han/Wistar rats. Two of the most dysregulated genes were Cyp1a1 and Nqo1, which are induced by TCDD across a wide range of tissues and are considered sensitive markers of TCDD exposure. The minimal response of the hypothalamic transcriptome to a lethal dose of TCDD at an early time-point suggests that the hypothalamus is not the predominant site of initial events leading to hypophagia and associated wasting. TCDD may affect feeding behaviour via events upstream or downstream of the hypothalamus, and further work is required to evaluate this at the level of individual hypothalamic nuclei and subregions.

  15. Nevada Test Site Radionuclide Inventory and Distribution Program: Report No. 3, Areas 3, 7, 8, 9, and 10

    SciTech Connect

    McArthur, R D; Mead, S W

    1987-02-01

    As part of the Nevada Test Site Radionuclide Inventory and Distribution Program, 115 soil samples were collected and more than 1200 in situ measurements of gamma-emitting radionuclides were made in the northern and eastern parts of Yucca Flat. Analysis of the data led to estimated inventories of 215 Ci of /sup 239,240/Pu, 128 Ci of /sup 137/Cs, 92 Ci of /sup 90/Sr, 36 Ci each of /sup 241/Am and /sup 60/Co, 31 Ci of /sup 102m/Rh, 27 Ci of /sup 238/Pu, 25 Ci of /sup 174/Lu, 10 Ci of /sup 152/Eu, 8 Ci of /sup 155/Eu, 7 Ci of /sup 154/Eu, 5 Ci of /sup 125/Sb, 4 Ci of /sup 101/Rh, and 2 Ci of /sup 134/Cs in the surface soil of the accessible portion of Areas 8 and 10. Similar calculations with the data from Areas 3, 7, and 9 gave estimates of 145 Ci of /sup 239,240/Pu, 89 Ci of /sup 152/Eu, 62 Ci of /sup 90/Sr, 25 Ci of /sup 137/Cs, 14 Ci of /sup 154/Eu, 11 Ci of /sup 241/Am, 6 Ci each of /sup 60/Co and /sup 238/Pu, and 4 Ci of /sup 155/Eu. Additional in situ measurements at 30 locations in the southern part of Yucca Flat confirmed the low levels of radioactivity found there by an aerial survey. 1 ref., 57 figs., 10 tabs.

  16. [{sup 3}H]-2,3,7,8-TCDD uptake and elimination kinetics of medaka (Oryzias latipes)

    SciTech Connect

    Schmieder, P.; Lothenbach, D.; Tietge, J.; Erickson, R.; Johnson, R.

    1995-10-01

    Uptake and elimination rate constants for [{sup 3}H]-2,3,7,8-tetrachlorodibenzo-p-dioxin ([{sup 3}H]TCDD) were estimated by exposing medaka (Oryzias latipes) to [{sup 3}H]TCDD in flowing water with no solvent carriers. Uptake was determined from body-burdens measured on exposure days 0, 2, 4, 6, 10, and 12. Elimination was quantified for whole fish after 28, 90, and 175 d in uncontaminated water. Medaka accumulated [{sup 3}H]TCDD at a rapid rate, achieving residues 24,000 times the water concentration after 12 d, with no indication of approach to steady state. After 6 months in uncontaminated water, the pg TCDD/g decreased by 69%, much of the decrease due to growth dilution as evidenced by only a 47% decrease in the pg TCDD/fish. Uptake and elimination rate constant (2,300 ml/g/d and 0.0045/d, respectively) were estimated by fitting a one-compartment, linear, mass-balance model to the data, adjusting for growth rate. The experimental design, including solvent-free delivery of [{sup 3}H]TCDD, exposure at concentrations below maximum water solubility, and measurement of fish growth and lipid content during a 6-month elimination phase, resulted in a predicted steady-state bioconcentration factor (BCF) for medaka of 510,000, a number considerably higher than previously reported for dioxin BCFs. Kinetic parameters were used to successfully predict TCDD BCF in medaka exposed independently.

  17. Dual fluorescence from an isonido ReIII rhenacarborane phosphine complex, [7,10-mu-H-7-CO-7,7-(PPh3)2-isonido-7,8,9-ReC2B7H9].

    PubMed

    Buckner, Steven W; Fischer, Matthew J; Jelliss, Paul A; Luo, Rensheng; Minteer, Shelley D; Rath, Nigam P; Siemiarczuk, Aleksander

    2006-09-01

    The complex [7,10-mu-H-7-CO-7,7-(PPh3)2-isonido-7,8,9-ReC2B7H9] has been synthesized by treatment of the complex salt [NHMe3][3,3-Cl2-3,3-(CO)2-closo-3,1,2-ReC2B9H11] with PPh3 in refluxing THF (tetrahydrofuran) and isolated as intensely colored orange-red microcrystals. Spectroscopic NMR and IR data have suggested that the product has a highly asymmetric structure with two inequivalent PPh3 ligands and a single CO ligand. Measurement of 11B NMR spectra in particular have indicated seven distinct boron vertexes, although the resulting cage degradation by removal of two BH vertexes was confirmed only following X-ray crystallographic analysis, which revealed the pentadecahedral isonido-7,8,9-ReC2B7 architecture. The 11B NMR resonances span an enormous chemical shift range (Deltadelta = 113), and this appears to be a direct consequence of the deshielding of the boron vertex directly opposite the quadrilateral |ReCCB| aperture. The new complex has been shown by electrochemical measurements to undergo a reversible one-electron oxidation. Digitally simulated cyclic voltammograms support a proposed square scheme (E(1/2) = 0.58, 0.69 V vs ferrocene) involving a reversible isonido-closo transition of the metallacarborane cage. Most unusually for a metallacarborane complex, ambient temperature solutions in CH2Cl2 and DMF have been shown to be intensely turquoise-blue fluorescent (lambda(em) = 442 nm, Phi = 0.012). Fluorescence spectroscopy measurements in MeTHF (2-methyltetrahydrofuran) glass at 77 K have indicated that the likely cause of such a broad emission is dual fluorescence (lambda(em) = 404, 505 nm), with both emissions displaying vibronic structure. Following excited-state lifetime decay analysis, the emissive behavior has been accredited to metal-perturbed 1IL states, with the lower energy emission arising from a slight geometric distortion of the initially excited complex.

  18. A model to evaluate past exposure to 2,3,7,8-TCDD.

    PubMed

    Pinsky, P F; Lorber, M N

    1998-01-01

    Data from several studies suggest that concentrations of dioxins rose in the environment from the 1930s to about the 1960s/70s and have been declining over the last decade or two. The most direct evidence of this trend comes from lake core sediments, which can be used to estimate past atmospheric depositions of dioxins. The primary source of human exposure to dioxins is through the food supply. The pathway relating atmospheric depositions to concentrations in food is quite complex, and accordingly, it is not known to what extent the trend in human exposure mirrors the trend in atmospheric depositions. This paper describes an attempt to statistically reconstruct the pattern of past human exposure to the most toxic dioxin congener, 2,3,7,8-TCDD (abbreviated TCDD), through use of a simple pharmacokinetic (PK) model which included a time-varying TCDD exposure dose. This PK model was fit to TCDD body burden data (i.e., TCDD concentrations in lipid) from five U.S. studies dating from 1972 to 1987 and covering a wide age range. A Bayesian statistical approach was used to fit TCDD exposure; model parameters other than exposure were all previously known or estimated from other data sources. The primary results of the analysis are as follows: (1) use of a time-varying exposure dose provided a far better fit to the TCDD body burden data than did using a dose that was constant over time; this is strong evidence that exposure to TCDD has, in fact, varied during the 20th century, (2) the year of peak TCDD exposure was estimated to be in the late 1960s, which coincides with peaks found in sediment core studies, (3) modeled average exposure doses during these peak years was estimated at 1.4-1.9 pg TCDD/kg-day, and (4) modeled exposure doses of TCDD for the late 1980s of less than 0.10 pg TCDD/kg-day correlated well with recent estimates of exposure doses around 0.17 pg TCDD/kg-day (recent estimates are based on food concentrations combined with food ingestion rates; food is

  19. Suppression of Adipogenesis by 5-Hydroxy-3,6,7,8,3',4'-Hexamethoxyflavone from Orange Peel in 3T3-L1 Cells.

    PubMed

    Wang, Yu; Lee, Pei-Sheng; Chen, Yi-Fen; Ho, Chi-Tang; Pan, Min-Hsiung

    2016-09-01

    We reported previously that hydroxylated polymethoxyflavones (HPMFs) effectively suppressed obesity in high-fat-induced mouse. In this study, we further investigated the molecular mechanism of action of 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone (5-OH-HxMF), one of major HPMFs in orange peel. Treatment of 5-OH-HxMF effectively inhibited lipid accumulation by 55-60% in a dose-dependent manner. The 5-OH-HxMF attenuated adipogenesis through downregulating adipogenesis-related transcription factors such as peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding proteins (C/EBPs), as well as downstream target fatty acid synthase and acetyl-CoA carboxylase (ACC). 5-OH-HxMF activated adenosine monophosphate-activated protein kinase signaling and silent mating type information regulation 1 (SIRTUIN 1 or SIRT1) in 3T3-L1 adipocytes to decrease lipid accumulation. In addition, the inhibition rate of lipid accumulation was compared between 5-OH-HxMF and 3,5,6,7,8,3',4'-heptamethoxyflavone (HpMF). 5-OH-HxMF inhibited lipid accumulation 15-20% more than HpMF did, indicating that hydroxyl group at position 5 can be a key factor in the suppression of adipogenesis. PMID:27542074

  20. Process for manufacturing bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene

    DOEpatents

    Rasmussen, Paul George; Lawton, Richard Graham

    2014-06-03

    A process to manufacture substituted tetracyano-hexaazatricyclics with the substitutions occurring at the 9 and 10 hydrogens. The process begins with 2,3-dichloro-5,6-dicyanopyrazine, which is reacted to form the desired tetracyano-hexaazatricyclic. Different process embodiments enable different reaction paths to the desired tetracyano-hexaazatricyclic. Different tetracyano-hexaazatricyclic embodiments include bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene and bis(2-methoxyethoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracen- e.

  1. Regioselective synthesis and estrogenicity of (+/-)-8-alkyl-5,7-dihydroxy-4-(4-hydroxyphenyl)-3,4-dihydrocoumarins.

    PubMed

    Roelens, Frederik; Huvaere, Kevin; Dhooge, Willem; Van Cleemput, Marjan; Comhaire, Frank; De Keukeleire, Denis

    2005-10-01

    Nine new (+/-)-8-alkyl-5,7-dihydroxy-4-(4-hydroxyphenyl)-3,4-dihydrocoumarins have been synthesized from 2,4,6-trimethoxybenzaldehyde via a short, efficient, and regioselective pathway, together with the unsubstituted analogue (+/-)-5,7-dihydroxy-4-(4-hydroxyphenyl)-3,4-dihydrocoumarin. The compounds were tested for estrogenic activity using a yeast-based estrogen screen. Weak estrogenicity was determined for seven members of the series.

  2. The concentration and distribution of 2,3,7,8-dibenzo-p-dioxins/-furans in chickens

    NASA Technical Reports Server (NTRS)

    Ferrario, J.; Byrne, C.

    2000-01-01

    The concentrations of the 2,3,7,8-Cl substituted dibenzo-p-dioxins/-furans (PCDDs/PCDFs) were determined in the edible tissues of whole chicken fryers and compared with the values found in their abdominal fat. The values are presented both on a whole weight basis and on a lipid adjusted basis for each tissue. While there is a marked difference in the concentration of the 2,3,7,8-dibenzo-p-dioxins in the edible tissues expressed on a whole weight basis, the lipid-adjusted concentrations of the individual dioxins were not statistically different in the various tissues. This validates the use of lipid adjusted concentrations of 2,3,7,8-PCDDs/PCDFs in abdominal fat for the determination of the presence of these compounds in different tissues.

  3. Nucleic acid-sensing toll-like receptors 3, 7 and 8 in esophageal epithelium, barrett's esophagus, dysplasia and adenocarcinoma.

    PubMed

    Helminen, Olli; Huhta, Heikki; Lehenkari, Petri P; Saarnio, Juha; Karttunen, Tuomo J; Kauppila, Joonas H

    2016-05-01

    Toll-like receptors (TLRs) are immunological receptors recognizing various microbial and endogenous ligands, such as DNA, RNA, and other microbial and host components thus activating immunological responses. The expression of TLRs in esophageal adenocarcinoma is not well known. The aim of this study was to evaluate expression patterns of those TLRs that sense nucleic acids in Barrett's esophagus with and without dysplasia and in esophageal adenocarcinoma. TLRs 3, 7 and 8 were stained immunohistochemically and evaluated in a cohort of patients with esophageal adenocarcinoma or dysplasia. Specimens with normal esophagus (n = 88), gastric (n = 67) or intestinal metaplasia (n = 51) without dysplasia, and low-grade (n = 42) or high-grade dysplasia (n = 37) and esophageal adenocarcinoma (n = 99) were studied. We used immunofluorescence to confirm the subcellular localization of TLRs. We found abundant expression of TLR3, 7 and 8 in esophageal squamous epithelium, columnar metaplasia, dysplasia and adenocarcinoma. Cytoplasmic expression of TLR3, TLR7 or TLR8 did not associate to clinicopathological parameters or prognosis in esophageal cancer. High nuclear expression of TLR8, confirmed with immunofluorescence, in cancer cells was observed in tumors of high T-stage (p < 0.01) and in tumors with organ metastasis (p < 0.001). High nuclear TLR8 expression was associated with poor prognosis (p < 0.001). The expression of TLR3, TLR7 and TLR8 increased toward dysplasia and adenocarcinoma. We demonstrated nuclear localization of TLR8, which associates with metastasis and poor prognosis. TLR3 and TLR7 do not seem to have prognostic significance in esophageal adenocarcinoma. PMID:27467941

  4. Shigella IpaH7.8 E3 ubiquitin ligase targets glomulin and activates inflammasomes to demolish macrophages

    PubMed Central

    Suzuki, Shiho; Mimuro, Hitomi; Kim, Minsoo; Ogawa, Michinaga; Ashida, Hiroshi; Toyotome, Takahito; Franchi, Luigi; Suzuki, Masato; Sanada, Takahito; Suzuki, Toshihiko; Tsutsui, Hiroko; Núñez, Gabriel; Sasakawa, Chihiro

    2014-01-01

    When nucleotide-binding oligomerization domain–like receptors (NLRs) sense cytosolic-invading bacteria, they induce the formation of inflammasomes and initiate an innate immune response. In quiescent cells, inflammasome activity is tightly regulated to prevent excess inflammation and cell death. Many bacterial pathogens provoke inflammasome activity and induce inflammatory responses, including cell death, by delivering type III secreted effectors, the rod component flagellin, and toxins. Recent studies indicated that Shigella deploy multiple mechanisms to stimulate NLR inflammasomes through type III secretion during infection. Here, we show that Shigella induces rapid macrophage cell death by delivering the invasion plasmid antigen H7.8 (IpaH7.8) enzyme 3 (E3) ubiquitin ligase effector via the type III secretion system, thereby activating the NLR family pyrin domain-containing 3 (NLRP3) and NLR family CARD domain-containing 4 (NLRC4) inflammasomes and caspase-1 and leading to macrophage cell death in an IpaH7.8 E3 ligase-dependent manner. Mice infected with Shigella possessing IpaH7.8, but not with Shigella possessing an IpaH7.8 E3 ligase-null mutant, exhibited enhanced bacterial multiplication. We defined glomulin/flagellar-associated protein 68 (GLMN) as an IpaH7.8 target involved in IpaH7.8 E3 ligase-dependent inflammasome activation. This protein originally was identified through its association with glomuvenous malformations and more recently was described as a member of a Cullin ring ligase inhibitor. Modifying GLMN levels through overexpression or knockdown led to reduced or augmented inflammasome activation, respectively. Macrophages stimulated with lipopolysaccharide/ATP induced GLMN puncta that localized with the active form of caspase-1. Macrophages from GLMN+/− mice were more responsive to inflammasome activation than those from GLMN+/+ mice. Together, these results highlight a unique bacterial adaptation that hijacks inflammasome activation via

  5. Localization of two metabotropic glutamate receptor genes, GRM3 and GRM8, to human chromosome 7q

    SciTech Connect

    Scherer, S.W.; Heng, H.H.Q.; Lap-Chee Tsui

    1996-01-15

    Metabotropic glutamate receptors (GRMs) are neutrotransmitter receptors that respond to glutamate stimulations by activating GTP-binding proteins and modulating second-messenger cascades. Eight related GRMs have been identified to date. In this study, we have mapped GRM3 and GRM8 to human chromosome 7q21.1-q21.2 and 7q31.3-q32.1, respectively, using somatic cell hybrid and fluorescence in situ hybridization analysis. A yeast artificial chromosome contig was constructed surrounding the genes, allowing their location to be integrated into the genetic and physical map of chromosome 7. 20 refs., 2 figs.

  6. QSPR study of solvent quenching of the 5D 0 → 7F 2 emission of Eu(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate) 3

    NASA Astrophysics Data System (ADS)

    Mercader, Andrew G.; Duchowicz, Pablo R.; Fernández, Francisco M.; Castro, Eduardo A.; Wolcan, Ezequiel

    2008-09-01

    We performed a predictive analysis, based on quantitative structure-property relationships (QSPR), of the luminescence lifetime ( τ) of Eu(fod) 3 in different solvents. The Eu(fod) 3 luminescent properties have been helpful as replacements for radioactivity, alternatives to standard fluorescent dyes and donors in energy transfer experiments, and are gaining expanding applications in wide variety of bioanalytical assays. Our best QSPR linear model constructed from 23 molecular structures combines four molecular descriptors, selected from more than a thousand geometrical, topological, quantum-mechanical and electronic types of descriptors.

  7. Li-Ion Conduction and Stability of Perovskite Li3/8Sr7/16Hf1/4Ta3/4O3.

    PubMed

    Huang, Bing; Xu, Biyi; Li, Yutao; Zhou, Weidong; You, Ya; Zhong, Shengwen; Wang, Chang-An; Goodenough, John B

    2016-06-15

    A solid Li-ion conductor with a high room temperature Li-ion conductivity and small interfacial resistance is required for its application in next-generation Li-ion batteries. Here, we prepared a cubic perovskite-related oxide with the general formula Li3/8Sr7/16Hf1/4Ta3/4O3 (LSHT) by a conventional solid-state reaction method, which was studied by X-ray diffraction, electrochemical impedance spectroscopy, and (7)Li MAS NMR. Li3/8Sr7/16Hf1/4Ta3/4O3 has a high Li-ion conductivity of 3.8 × 10(-4) S cm(-1) at 25 °C and a low activation energy of 0.36 eV in the temperature range 298-430 K. It exhibits both high stability and small interfacial resistance with commercial organic liquid electrolytes, which makes it promising as a separator in Li-ion batteries. PMID:27215282

  8. COMPARATIVE SENSITIVITY OF DIFFERENT LIFE-STAGES OF MEDAKA AND SALMONID FISHES TO 2,3,7,8-TCDD

    EPA Science Inventory

    The early life stages of fish are known to be more sensitive than the adults to the toxicological effects of 2,3,7,8-tetrachlorodibenzo(p)dioxin (TCDD). Embryo larval stages of medake, for example, experience 50% lethality when TCDD residues in the eggs are 1396 pg/g. By contrast...

  9. Percutaneous Absorption of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (TCDD) From Soil (Journal Article)

    EPA Science Inventory

    Eight dermal absorption (two in vivo; six in vitro) and one intravenous experiment were conducted using 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) either neat (high dose at ~250 µg/cm2 and low dose at 10 ng/cm2) or sorbed on a low organic (LOS) or high organic (HOS) soil at 1 ppm...

  10. TERATOGENIC RESPONSES OF TGFALPHA KNOCKOUT FETUSES TO 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)

    EPA Science Inventory

    ABBOTT1, B.D., A.R. BUCKALEW1, and P.L. BRYANT2. 1Reproductive Toxicology Division, EPA, RAP, NC; 2Dept. Environ. Sciences & Engineering, UNC, Chapel Hill, NC. Teratogenic responses of TGF knockout fetuses to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

    TCDD induces cl...

  11. Fine Mutational Analysis of 2B8 and 3H7 Tag Epitopes with Corresponding Specific Monoclonal Antibodies.

    PubMed

    Kim, Tae-Lim; Cho, Man-Ho; Sangsawang, Kanidta; Bhoo, Seong Hee

    2016-06-30

    Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report. We present here fine epitope mapping of these two antibodies by using truncation and substitution of original epitope sequences in order to identify minimized epitope peptides. The previously reported original epitope sequences for 2B8 and 3H7 were truncated from both sides. Our analysis showed that the minimal peptide sequence lengths for 2B8 and 3H7 antibodies were nine amino acids (RDPLPFFPP) and six amino acids (PGEIEE), respectively. We further characterized these peptides in order to investigate their reactivity after single deletion and single substitution of the original peptides. We found that single-substituted 2B8 epitope (RDPLPAFPP) and dual-substituted 3H7 epitope (PGEIAD) showed significantly increased reactivity. These two antibodies with high reactivity for the short modified peptide sequences are valueble for developing new peptide tags for protein research. PMID:27137090

  12. CYP1A2 IS NOT REQUIRED FOR 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN-INDUCED IMMUNOSUPPRESSION

    EPA Science Inventory

    ABSTRACT
    One of the most sensitive and reproducible immunotoxic endpoints of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) exposure is suppression of the antibody response to sheep red blood cells (SRBCs) in mice. Immunosuppression occurs in concert with hepatomegaly and associ...

  13. Fine Mutational Analysis of 2B8 and 3H7 Tag Epitopes with Corresponding Specific Monoclonal Antibodies

    PubMed Central

    Kim, Tae-Lim; Cho, Man-Ho; Sangsawang, Kanidta; Bhoo, Seong Hee

    2016-01-01

    Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report. We present here fine epitope mapping of these two antibodies by using truncation and substitution of original epitope sequences in order to identify minimized epitope peptides. The previously reported original epitope sequences for 2B8 and 3H7 were truncated from both sides. Our analysis showed that the minimal peptide sequence lengths for 2B8 and 3H7 antibodies were nine amino acids (RDPLPFFPP) and six amino acids (PGEIEE), respectively. We further characterized these peptides in order to investigate their reactivity after single deletion and single substitution of the original peptides. We found that single-substituted 2B8 epitope (RDPLPAFPP) and dual-substituted 3H7 epitope (PGEIAD) showed significantly increased reactivity. These two antibodies with high reactivity for the short modified peptide sequences are valueble for developing new peptide tags for protein research. PMID:27137090

  14. SORPTION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TO SOILS FROM WATER/METHANOL MIXTURES

    EPA Science Inventory

    Sorption of 14C-labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to soils from water/methanol mixtures has been evaluated by batch shake testing. Uncontaminated soils from Times Beach, MO, were used in these experiments and ranged in fraction organic carbon (U...

  15. THE CONCENTRATION AND DISTRIBUTION OF 2,3,7,8-DIBENZO-P-DIOXINS / - FURANS IN CHICKENS

    EPA Science Inventory

    The concentrations of 2,3,7,8-Cl substituted dibenzo-p-dioxins/-furans (PCDDs/PCDFs) were determined in the edible tissues of whole chicken fryers and compared with the values found in their abdominal fat. The values are presented both on a whole weight basis and on a lipid-adju...

  16. Organocatalyzed enantioselective synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carboxylates

    PubMed Central

    Ramireddy, Naresh; Abbaraju, Santhi; Zhao, Cong-Gui

    2011-01-01

    The organocatalyzed enantioselective synthesis of biologically active 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carboxylate derivatives was achieved using bifunctional cinchona alkaloids as the catalysts. Using quinine thiourea as the catalyst, the tandem Michael addition-cyclization reaction between 1,3-cyclohexanediones and alkylidenecyanoacetate derivatives gives the desired products in high yields (up to 92%) and good ee values (up to 82%). PMID:22081731

  17. Plate Tectonics at 3.8-3.7 Ga: Field Evidence from the Isua Accretionary Complex, Southern West Greenland.

    PubMed

    Komiya; Maruyama; Masuda; Nohda; Hayashi; Okamoto

    1999-09-01

    A 1&rcolon;5000 scale mapping was performed in the Isukasia area of the ca. 3.8-Ga Isua supracrustal belt, southern West Greenland. The mapped area is divided into three units bounded by low-angle thrusts: the Northern, Middle, and Southern Units. The Southern Unit, the best exposed, is composed of 14 subunits (horses) with similar lithostratigraphy, bound by layer-parallel thrusts. Duplex structures are widespread in the Isua belt and vary in scale from a few meters to kilometers. Duplexing proceeded from south to north and is well documented in the relationship between link- and roof-thrusts. The reconstructed lithostratigraphy of each horse reveals a simple pattern, in ascending order, of greenstone with low-K tholeiitic composition with or without pillow lava structures, chert/banded iron-formation, and turbidites. The cherts and underlying low-K tholeiites do not contain continent- or arc-derived material. The lithostratigraphy is quite similar to Phanerozoic "oceanic plate stratigraphy," except for the abundance of mafic material in the turbidites. The evidence of duplex structures and oceanic plate stratigraphy indicates that the Isua supracrustal belt is the oldest accretionary complex in the world. The dominantly mafic turbidite composition suggests that the accretionary complex was formed in an intraoceanic environment comparable to the present-day western Pacific Ocean. The duplex polarity suggests that an older accretionary complex should occur to the south of the Isua complex. Moreover, the presence of seawater (documented by a thick, pillow, lava unit at the bottom of oceanic plate stratigraphy) indicates that the surface temperature was less than ca. 100 degrees C in the Early Archean. The oceanic geotherm for the Early Archean lithosphere as a function of age was calculated based on a model of transient half-space cooling at given parameters of surface and mantle temperatures of 100 degrees and 1450 degrees C, respectively, suggesting that the

  18. Evaluation of the oral subchronic toxicity of HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2 -benzopyran) in the rat.

    PubMed

    Api, A M; Ford, R A

    1999-12-20

    1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-ben zopyran (HHCB) is used in a wide variety of fragrances in consumer products. Because of the widespread exposure to this material, a 90-day oral feeding study in accordance with OECD guidelines No. 408, with 4-week recovery periods for selected rats, was conducted. HHCB was added to the diet of rats at levels calculated to result in mean daily doses of 5, 15, 50 or 150 mg HHCB/kg. On completion of the treatment period, three males and three females from the high dose and control groups were maintained for a treatment free period of 4 weeks. No adverse effects were revealed from clinical examination or following extensive histopathological examinations. There were no significant findings at any dose level; a NOAEL of 150 mg/kg per day was concluded. As a supplement to the main study, histopathological examination of the prostate, seminal vesicles, mammary gland and testes of males and ovaries, mammary gland, uterus and vagina of females was undertaken on all animals in all test groups. This examination did not reveal any evidence of hormonal effects.

  19. Relations structurales entre U 3O 8 et quelques fluorures mixtes de formules M2M' 3F 11, MM' 2F 7 et MM' 3F 10

    NASA Astrophysics Data System (ADS)

    Aléonard, S.; Le Fur, Y.; Champarnaud-Mesjard, J. C.; Frit, B.; Roux, M. Th.

    1983-01-01

    U 3O 8 oxide, as well as M2M' 3F 11, MM' 2F 7 and MM' 3F 10 fluorides, with M = Rb, Tl, Cs, NH 4 and M' = In, Lu, Yb, Tm, is described as the regular repetition according to the … A-A-A … sequence of identical and parallel sheets of edge-and corner-sharing M'F 7 or UO 7 pentagonal bipyramids and M'F 6 octahedra. M' and U atoms are systematically located at the lattice points of a pseudohexagonal network, but in the fluorides some of these lattice points are vacant, producing hexagonal tunnels in which M atoms are located. It is shown that in the two kinds of compounds the same linear chains and M' 3X17 groups of pentagonal bipyramids are present, and that the transformation of the U 3O 8 structure into the fluorides can be achieved by an ordered substitution of some linear … UOUO … chains by … M- M- M … chains. All these structures can be described with the same structural model based on the chemical twinning principle.

  20. 28 CFR 8.7 - Judicial forfeiture.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Judicial forfeiture. 8.7 Section 8.7 Judicial Administration DEPARTMENT OF JUSTICE FBI FORFEITURE AUTHORITY FOR CERTAIN STATUTES § 8.7 Judicial... 5312(a)(3) of title 31 of the United States Code, the Special Agent in Charge of the FBI field...

  1. 28 CFR 8.7 - Judicial forfeiture.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Judicial forfeiture. 8.7 Section 8.7 Judicial Administration DEPARTMENT OF JUSTICE FBI FORFEITURE AUTHORITY FOR CERTAIN STATUTES § 8.7 Judicial... 5312(a)(3) of title 31 of the United States Code, the Special Agent in Charge of the FBI field...

  2. 28 CFR 8.7 - Judicial forfeiture.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Judicial forfeiture. 8.7 Section 8.7 Judicial Administration DEPARTMENT OF JUSTICE FBI FORFEITURE AUTHORITY FOR CERTAIN STATUTES § 8.7 Judicial... 5312(a)(3) of title 31 of the United States Code, the Special Agent in Charge of the FBI field...

  3. The thermodynamic properties of 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene

    SciTech Connect

    Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.; Steele, W.V.

    1992-12-01

    Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, vibrating-tube densitometry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical properties were estimated for both materials based on the measurement results. Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gases for selected temperatures between 380 K and 700 K. The property-measurement results reported here for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene are the first for these important intermediates in the pyrene/H{sub 2} hydrogenation reaction network.

  4. The synthesis and formation process of a new cubic conductive Cu7O(8-y)(NO3) compound

    NASA Astrophysics Data System (ADS)

    Yazawa, Ichiro; Sugise, Ryoji; Terada, Norio; Jo, Masatoshi; Oka, Kunihiko

    1990-08-01

    The synthesis and formation process of a new cubic conductive Cu7O(8-y)(NO3) compound was studied. This material was formed as an intermediate compound in the decomposition process of copper nitrate by a firing process in oxygen flowing gas. It has a CuO2 plane in its lattice structure and is a parent material of the new metallic copper oxide compounds.

  5. Development and field validation of a multimedia exposure assessment model for waste load allocation in aquatic ecosystems: Application to 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in the Fraser River Watershed

    SciTech Connect

    Gobas, F.A.P.; Pasternak, J.P.; Lien, K.; Duncan, R.K.

    1998-08-15

    Knowledge of the relationship between contaminant emissions and ambient concentrations is crucial in achieving environmental quality objectives. This paper reports the development and field validation of EcoFate, a time dependent multimedia mass balance simulation model of the environmental distribution food-chain accumulation of organic contaminants in aquatic ecosystems. The purpose of the model is to present a methodology for deriving maximum daily-loading estimates in accordance with environmental quality objectives for a variety of aquatic ecosystems impacted by emissions from one or several point or nonpoint sources. The application of the model to multiple, time-varying pulp and paper mill discharges of 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in the Fraser-Thompson River system from 1988 to 1995 is demonstrated. The ability of the model to predict chemical concentrations in various environmental media and organisms resulting from chemical emissions is tested against field data collected over a 7 year period. The results include (1) a comparison of observed and predicted concentrations, (2) an assessment of uncertainty, and (3) a test of the model`s temporal response to changes in contaminant loadings. The application of the model for the derivation of maximum daily loadings for multiple point sources in watersheds is illustrated.

  6. 2,3,4,7,8-pentachlorodibenzofuran is a more potent cytochrome P4501A inducer than 2,3,7,8-tetrachlorodibenzo-p-dioxin in herring gull hepatocyte cultures.

    PubMed

    Hervé, Jessica C; Crump, Doug L D; McLaren, Kristina K; Giesy, John P; Zwiernik, Matthew J; Bursian, Steven J; Kennedy, Sean W

    2010-09-01

    Concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) on cytochrome P4501A (CYP1A) induction were determined in primary cultures of embryonic herring gull (Larus argentatus) hepatocytes exposed for 24 h. Based on the concentration that induced 50% of the maximal response (EC50), the relative potencies of TCDD and TCDF did not differ by more than 3.5-fold. However, also based on the EC50, PeCDF was 40-fold, 21-fold, and 9.8-fold more potent for inducing ethoxyresorufin-O-deethylase (EROD) activity, CYP1A4 mRNA expression, and CYP1A5 mRNA expression than TCDD, respectively. The relative CYP1A-inducing potencies of PeCDF and of other dioxin-like chemicals (DLCs) in herring gull hepatocytes (HEH RePs), along with data on concentrations of DLCs in Great Lakes herring gull eggs, were used to calculate World Health Organization toxic equivalent (WHO-TEQ) concentrations and herring gull embryonic hepatocyte toxic equivalent (HEH-TEQ) concentrations. The analysis indicated that, when using avian toxic equivalency factors (TEFs) recommended by the WHO, the relative contribution of TCDD (1.1-10.2%) to total WHO-TEQ concentration was higher than that of PeCDF (1.7-2.9%). These results differ from the relative contribution of TCDD and PeCDF when HEH RePs were used; PeCDF was a major contributor (36.5-52.9%) to total HEH-TEQ concentrations, whereas the contribution by TCDD (1.2-10.3%) was less than that of PeCDF. The WHO TEFs for avian species were largely derived from studies with the domestic chicken (Gallus gallus domesticus). The findings of the present study suggest that it is necessary to determine the relative potencies of DLCs in wild birds and to re-evaluate their relative contributions to the biochemical and toxic effects previously reported in herring gulls and other avian species.

  7. 2,3,4,7,8-Pentachlorodibenzofuran is far less potent than 2,3,7,8-tetrachlorodibenzo-p-dioxin in disrupting the pituitary–gonad axis of the rat fetus

    SciTech Connect

    Taura, Junki; Takeda, Tomoki; Fujii, Misaki; Hattori, Yukiko; Ishii, Yuji; Kuroki, Hiroaki; Tsukimori, Kiyomi; Uchi, Hiroshi; Furue, Masutaka; Yamada, Hideyuki

    2014-11-15

    The effect of 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) on the fetal pituitary–gonad axis was compared with that produced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in Wistar rats. Maternal treatment at gestational day (GD) 15 with PnCDF and TCDD reduced the fetal expression at GD20 of pituitary luteinizing hormone (LH) and the testicular proteins necessary for steroidogenesis. The relative potencies of PnCDF ranged from 1/42nd to 1/63rd of the TCDD effect. While PnCDF, at a dose sufficient to cause a reduction in fetal LH, provoked defects in sexual behavior at adulthood, a dose less than the ED{sub 50} failed to produce any abnormality. There was a loss of fetal body weight following in utero exposure to PnCDF, and the effect of PnCDF was also much less than that of TCDD. The disturbance in fetal growth was suggested to be due to a reduction in the level of fetal growth hormone (GH) by dioxins. The disorder caused by PnCDF/TCDD in the fetal pituitary–gonad axis occurred at doses less than those needed to cause wasting syndrome in pubertal rats. The harmful effect of PnCDF relative to TCDD was more pronounced in fetal rats than in pubertal rats. These lines of evidence suggest that: 1) PnCDF as well as TCDD imprints defects in sexual behavior by disrupting the fetal pituitary–gonad axis; 2) these dioxins hinder fetal growth by reducing the expression of fetal GH; and 3) the fetal effects of PnCDF/TCDD are more sensitive than sub-acute toxicity during puberty, and the relative effect of PnCDF varies markedly depending on the indices used. - Highlights: • 2,3,4,7,8-Pentachlorodibenzofuran (PnCDF) lowers gonadal steroidogenesis in fetuses. • PnCDF exerts the above effect through an initial attenuation in gonadotropin level. • PnCDF imprints sexual immaturity by transiently disrupting the pituitary–gonad axis. • PnCDF also disturbs pup growth probably due to a reduction in growth hormone level. • The above effects are far lesser in PnCDF than 2,3,7,8

  8. Biochemical and histological responses in rainbow trout (Oncorhynchus mykiss) exposed to 2,3,4,7,8-pentachlorodibenzofuran

    SciTech Connect

    Brown, S.B.; Evans, R.E.; Lockhart, W.L.; Delorme, P.D.; Ward, F.J.; Muir, D.C.G.

    1998-01-01

    Rainbow trout were given an intraperitoneal injection of corn oil containing 0 or 8.8 nmol (3 {micro}g) [{sup 14}C]2,3,4,7,8-pentachlorodibenzofuran (P{sub 5}CDF)/kg and were then held on a light cycle that induced spawning 10 months later. At 5- to 6-week intervals, blood samples were collected to monitor plasma levels of 17{beta}-estradiol (E{sub 2}), testosterone (T), thyroxine (T{sub 4}), 3,5,3{prime}-triiodo-L-thyronine (T{sub 3}), and calcium; packed cell volume (PCV); and differential blood cell counts. Fish were sacrificed after spawning to examine tissue P{sub 5}CDF concentration, liver ethoxyresorufin-O-deethylase (EROD), liver vitamins (retinoids and tocopherol), histology (liver, thyroid), and growth parameters. The P{sub 5}CDF injections produced tissue 2,3.7,8-tetrachlorodibenzo-p-dioxin toxic equivalent concentrations comparable to those reported in salmonids from contaminated areas. Highest P{sub 5}CDF concentrations occurred in gut and liver, but muscle accounted for the greatest proportion of the dose. Plasma hormone and calcium concentrations followed predicted seasonal patterns in both control and exposed fish. PCV was unchanged by repeated blood sampling but differential blood cell counts showed adaptive responses to blood removal. The P{sub 5}CDF exposure caused transient reductions in circulating lymphocytes and elevated EROD. Additionally, P{sub 5}CDF increased liver size and depleted retinoid stores in male fish. Liver histology, somatic growth, and gonadal development were unaltered by P{sub 5}CDF during the first reproductive cycle after exposure.

  9. Effect of thyroidectomy and thyroxine on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced immunotoxicity

    SciTech Connect

    Pazdernik, T.L.; Rozman, K.K.

    1985-02-18

    Radiothyroidectomy protected against 2,3,7,8-tetrachloro dibenzo-p-dioxin (TCDD)-induced immunotoxicity in rats as assessed by the spleen anti-SRBC plaque-forming cell assay. Thyroxin (T/sub 4/) replacement therapy partially reversed the effects of thyroidectomy on T/sub 4/ and triiodothyronine (T/sub 3/) serum levels, body weight and immune function as well as restored TCDD-induced immunotoxicity. Thus, hypothyroidism induced by TCDD exposure can be viewed as a protective response of the organism to reduce the insult caused by TCDD.

  10. Developmental and posthatch effects of in ovo exposure to 2,3,7,8-TCDD, 2,3,4,7,8-PECDF, and 2,3,7,8-TCDF in Japanese quail (Coturnix japonica), common pheasant (Phasianus colchicus), and white leghorn chicken (Gallus gallus domesticus) embryos.

    PubMed

    Cohen-Barnhouse, Andrew M; Zwiernik, Matthew J; Link, Jane E; Fitzgerald, Scott D; Kennedy, Sean W; Giesy, John P; Wiseman, Steve; Jones, Paul D; Newsted, John L; Kay, Denise; Bursian, Steven J

    2011-07-01

    An egg injection study was conducted to confirm a proposed model of relative sensitivity of three avian species to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like chemicals. It was previously reported that the order of species sensitivity to in ovo exposure to TCDD, 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or 2,3,7,8-tetrachlorodibenzofuran (TCDF) at doses ranging from 0.044 to 37 picomoles (pmol)/g egg was the chicken (Gallus gallus domesticus), common pheasant (Phasianus colchicus), and Japanese quail (Coturnix japonica) based on embryo mortality and hepatic enzyme induction. In the present study, the incidence of developmental deformities, changes in body and relative organ masses, and organ pathology of hatchlings as additional indicators of species sensitivity were assessed; in addition, embryo mortality in the three species was categorized by stage of development. Embryo mortality varied temporally with significant increases generally occurring after organogenesis and just prior to hatching. A significant increase in the percentage of developmental deformities was observed only in Japanese quail exposed to TCDF. Body and relative organ masses of quail, pheasants, and chickens dosed in ovo with TCDD, PeCDF, or TCDF were not consistently affected. Chemical-related pathology occurred only in livers of quail at the greatest doses of each compound. These results indicated that the incidence of developmental deformities, changes in body and relative organ masses and organ pathology could not be used as indicators of species sensitivity or chemical potency.

  11. Diatom-derived oxylipins induce cell death in sea urchin embryos activating caspase-8 and caspase 3/7.

    PubMed

    Ruocco, Nadia; Varrella, Stefano; Romano, Giovanna; Ianora, Adrianna; Bentley, Matt G; Somma, Domenico; Leonardi, Antonio; Mellone, Stefano; Zuppa, Antonio; Costantini, Maria

    2016-07-01

    Diatoms are an important class of unicellular algae that produce bioactive secondary metabolites with cytotoxic activity collectively termed oxylipins, including polyunsaturated aldehydes (PUAs), hydroxyacids (HEPEs), oxo-acids and epoxyalcohols. Previous results showed that at higher concentrations, the PUA decadienal induced apoptosis on copepods and sea urchin embryos via caspase-3 activation; at lower concentrations decadienal affected the expression levels of the caspase-8 gene in embryos of the sea urchin Paracentrotus lividus. In the present work, we studied the effects of other common oxylipins produced by diatoms: two PUAs (heptadienal and octadienal) and four hydroxyacids (5-, 9- 11- and 15-HEPE) on P. lividus cell death and caspase activities. Our results showed that (i) at higher concentrations PUAs and HEPEs induced apoptosis in sea urchin embryos, detected by microscopic observation and through the activation of caspase-3/7 and caspase-8 measured by luminescent assays; (ii) at low concentrations, PUAs and HEPEs affected the expression levels of caspase-8 and caspase-3/7 (isolated for the first time here in P. lividus) genes, detected by Real Time qPCR. These findings have interesting implications from the ecological point of view, given the importance of diatom blooms in nutrient-rich aquatic environments.

  12. Diatom-derived oxylipins induce cell death in sea urchin embryos activating caspase-8 and caspase 3/7.

    PubMed

    Ruocco, Nadia; Varrella, Stefano; Romano, Giovanna; Ianora, Adrianna; Bentley, Matt G; Somma, Domenico; Leonardi, Antonio; Mellone, Stefano; Zuppa, Antonio; Costantini, Maria

    2016-07-01

    Diatoms are an important class of unicellular algae that produce bioactive secondary metabolites with cytotoxic activity collectively termed oxylipins, including polyunsaturated aldehydes (PUAs), hydroxyacids (HEPEs), oxo-acids and epoxyalcohols. Previous results showed that at higher concentrations, the PUA decadienal induced apoptosis on copepods and sea urchin embryos via caspase-3 activation; at lower concentrations decadienal affected the expression levels of the caspase-8 gene in embryos of the sea urchin Paracentrotus lividus. In the present work, we studied the effects of other common oxylipins produced by diatoms: two PUAs (heptadienal and octadienal) and four hydroxyacids (5-, 9- 11- and 15-HEPE) on P. lividus cell death and caspase activities. Our results showed that (i) at higher concentrations PUAs and HEPEs induced apoptosis in sea urchin embryos, detected by microscopic observation and through the activation of caspase-3/7 and caspase-8 measured by luminescent assays; (ii) at low concentrations, PUAs and HEPEs affected the expression levels of caspase-8 and caspase-3/7 (isolated for the first time here in P. lividus) genes, detected by Real Time qPCR. These findings have interesting implications from the ecological point of view, given the importance of diatom blooms in nutrient-rich aquatic environments. PMID:27130972

  13. Dystonia and tremor following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Klawans, H.L.

    1987-01-01

    Forty-seven railroad workers who were exposed to polychlorinated phenols, including dioxin (TCDD), during 1979 while cleaning up the chemical spillage following damage to a tank car filled with these chemicals were followed medically for the subsequent 6 years. Two committed suicide. The initial neurological complaints included a sense of fatigue and muscle aching, both of which have been reported in other individuals following dioxin exposure. On detailed neurological examination in December, 1985, 24 of 45 had dystonic writer's cramp and/or other action dystonias of the hands. None of the involved individuals had a family history of dystonia, and all 24 dated the onset of the dystonia to the first 2 to 3 years subsequent to their toxic exposure. The dystonias varied in severity but were usually mild. No other types of dystonic involvement were recognized. Thirty-five of the 45 individuals also manifested postural and terminal intention tremor which resembled benign essential tremor. None of the involved individuals had a family history of tremor, and all 35 of those affected dated the onset of the tremor to some time subsequent to their toxic exposure. Forty-three of 45 patients had histories and findings suggestive of peripheral neuropathy. This is the first report relating any type of dystonia to prior dioxin exposure and the first report relating action dystonia, such as dystonic writer's cramp, and postural/terminal intention tremor, to toxic exposure of any type.

  14. Disposition of fragrance ingredient [14C]1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone in male Fisher rats following oral administration and dermal application.

    PubMed

    Waidyanatha, Suramya; Ryan, Kristen

    2014-08-01

    1. Disposition of 1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (β-OTNE), a fragrance ingredient in variety of consumer products, was investigated following a single oral (20 mg/kg) or a dermal (55 or 550 mg/kg) dose of [(14)C]β-OTNE to male Fisher rats. 2. Following oral administration, 28% and 39% of the dose was recovered in urine and feces, respectively, 48 h following administration. About 73% of a 20 mg/kg dose was excreted in bile within 48 h post-administration supporting significant oral absorption of [(14)C]β-OTNE. 3. Following dermal application to a covered site, absorption of [(14)C]β-OTNE 96 h following application was low (ca. 14%) and dose-independent. When the dose site was uncovered, the absorption increased to ca. 33% (55 mg/kg) and ca. 72% (550 mg/kg). 4. [(14)C]β-OTNE was distributed to tissues following both routes of exposure with the highest radioactive equivalents found in bladder, liver, kidney, adipose and pancreas. 5. Elimination of [(14)C]β-OTNE equivalents in blood and tissues was slow following both oral and dermal application suggesting potential for accumulation following multiple exposure. PMID:24533629

  15. Disposition of fragrance ingredient [14C]1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone in male Fisher rats following oral administration and dermal application.

    PubMed

    Waidyanatha, Suramya; Ryan, Kristen

    2014-08-01

    1. Disposition of 1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (β-OTNE), a fragrance ingredient in variety of consumer products, was investigated following a single oral (20 mg/kg) or a dermal (55 or 550 mg/kg) dose of [(14)C]β-OTNE to male Fisher rats. 2. Following oral administration, 28% and 39% of the dose was recovered in urine and feces, respectively, 48 h following administration. About 73% of a 20 mg/kg dose was excreted in bile within 48 h post-administration supporting significant oral absorption of [(14)C]β-OTNE. 3. Following dermal application to a covered site, absorption of [(14)C]β-OTNE 96 h following application was low (ca. 14%) and dose-independent. When the dose site was uncovered, the absorption increased to ca. 33% (55 mg/kg) and ca. 72% (550 mg/kg). 4. [(14)C]β-OTNE was distributed to tissues following both routes of exposure with the highest radioactive equivalents found in bladder, liver, kidney, adipose and pancreas. 5. Elimination of [(14)C]β-OTNE equivalents in blood and tissues was slow following both oral and dermal application suggesting potential for accumulation following multiple exposure.

  16. Effects and mechanisms of 8-prenylnaringenin on osteoblast MC3T3-E1 and osteoclast-like cells RAW264.7

    PubMed Central

    Luo, Dan; Kang, Lumei; Ma, Yuhui; Chen, Hongping; Kuang, Haibin; Huang, Qiren; He, Ming; Peng, Weijie

    2014-01-01

    8-Prenylnaringenin (8-PN) is a phytoestrogen with the highest estrogenic activity. The objective of the present study was to confirm the superiority of 8-PN on bone metabolisms and the estrogen receptor (ER) subtype mediating effects of 8-PN. The osteoblast MC3T3-E1 and osteoclast-like cell line RAW264.7 were treated with 17β-estradiol (10−8 mol/L), genistein (10−5 mol/L), daidzein (10−5 mol/L), 8-PN (10−5 mol/L) alone or in the presence of ERα antagonist MPP (10−7 mol/L) and ERβ antagonist PTHPP (1.5 × 10−7 mol/L). It has been found that 8-PN did not affect osteoblast proliferation, and that 8-PN increased alkaline phosphatase (ALP) activity, osteocalcin (OCN) concentrations, and the mineralized nodules. 8-PN inhibited RAW264.7 differentiating into osteoclasts and reduced the pit area of bone resorption. 8-PN could also inhibit the protein and mRNA expression of receptor activator of nuclear factor-κB ligand (RANKL) in osteoblasts, and conversely promote the expression of osteoprotegerin (OPG). These effects of 8-PN were mainly inhibited not by PTHPP but by MPP and they were weaker than estrogen's effects but stronger than those of genistein and daidzein. In conclusion, the effects of 8-PN on promoting osteoblastic bone formation and inhibiting osteoclastic bone resorption were mediated by ERα instead of ERβ and the efficacy was more potent than that of the two classic phytoestrogens: genistein and daidzein. PMID:25473491

  17. Bioaccumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran and extractable organic chlorine at a bleached-kraft mill site in a northern Canadian river system

    SciTech Connect

    Owens, J.W. ); Swanson, S.M. ); Birkholz, D.A. )

    1994-02-01

    Abiotic and biotic environmental compartments in a northern Canadian river system have been analyzed for poly-chlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and extractable organochlorines (EOCl) down-stream of a bleached-kraft mill. The water column, deposited and suspended sediments, invertebrates, and tissues from several fish species were analyzed. The data indicate that (a) conversion of the mill bleaching process to 100% chlorine dioxide virtually eliminated the discharge of PCDDs and PCDFs; (b) PCDD, PCDF, and EOCl transport occurred primarily in suspended sediments; and (c) the food choice of filter-feeding insects by specific fish species such as the mountain whitefish (Prosopium williamsoni) was an important determinant in the food-chain transfer of the principal compounds, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 2,3,7,8-tetrachlorodibenzofuran (TCDF). Relative to mountain whitefish, TCDD and TCDF levels in another bottom feeding species, longnose sucker (Catostomus catostomus), were at least an order of magnitude lower. Food-chain biomagnification of TCDD and TCDF was not observed in omnivorous and predatory species, burbot (Lota lota) and walleye (Stizostedium vitreum), for which lipid-adjusted levels were similar to those in the longnose sucker. These data indicate that organism lipid levels alone are not sufficient to predict species-specific bioaccumulation of these hydrophobic compounds, and that site-specific transport and species food choice parameters should be included in bioaccumulation models for hydrophobic compounds such as PCDDs and PCDFs.

  18. Microwave-assisted Synthesis and antifungal activity of coumarin[8,7-e][1,3]oxazine derivatives.

    PubMed

    Zhang, Ming-Zhi; Zhang, Rong-Rong; Yin, Wen-Zheng; Yu, Xiang; Zhang, Ya-Ling; Liu, Pin; Gu, Yu-Cheng; Zhang, Wei-Hua

    2016-08-01

    The synthesis of novel coumarin[8,7-e][1,3]oxazine derivatives through a microwave-assisted three-component one-pot Mannich reaction is described in this study. All the target compounds were evaluated in vitro for their antifungal activity against Botrytis cinerea, Colletotrichum capsici, Alternaria solani, Gibberella zeae, Rhizoctonia solani, and Alternaria mali. The preliminary bioassays showed that 5e, 5m, and 5s exhibited good antifungal activity and the most active compound was 5m with an [Formula: see text] value as low as 2.1 nM against Botrytis cinerea. PMID:26880591

  19. Disposition and excretion of 14C-AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene) and 14c-hhcb (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-gamma-2-benzopyran) after intravenous administration to Sprague-Dawley rats and domestic pigs.

    PubMed

    Api, Anne Marie; Ritacco, Gretchen; Sipes, I Glenn

    2013-07-01

    7-Acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN ) and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyran (HHCB) are polycyclic musks widely used as fragrance ingredients in consumer products. Because their metabolic fate following systemic exposure is not fully characterized, disposition and excretion of (14)C-AHTN- and (14)C-HHCB-derived radioactivity were studied in Sprague-Dawley rats and domestic pigs following a single intravenous dose. Rats administered with AHTN or HHCB excreted 21% or 28% of the radioactivity in urine and 67% or 61% in feces, respectively, within 7 days. In pigs administered AHTN or HHCB, 86% or 74% of the dose was excreted in the urine, and 12% or 15% in feces, respectively, during the 14-day collection period. Radioactivity in the whole blood and plasma of both species and tissues of rats declined steadily until the end of the study (28 days) for both the materials. Radioactivity in rat adipose tissue reached peak at 2 hours after dosing, decreasing steadily thereafter. Radioactivity in pig blood declined rapidly from 70 ng equivalents/g at 10 minutes to 1 ng equivalent/g or less by 28 days after administration of either AHTN or HHCB. Radioactivity in pig skin and adipose tissue decreased to below the limit of detection by 28 days for both the materials. Thin-layer chromatography showed multiple radioactive components in both species' urine after administration of either material. Components found in the urine of the 2 species were qualitatively similar but quantitatively different. Both AHTN and HHCB were completely metabolized and excreted. No unchanged parent compound was detected in rat or pig urine.

  20. Helix 8 and the i3 Loop of the Muscarinic M3 Receptor Are Crucial Sites for Its Regulation by the Gβ5-RGS7 Complex

    PubMed Central

    2015-01-01

    The muscarinic M3 receptor (M3R) is a Gq-coupled receptor and is known to interact with many intracellular regulatory proteins. One of these molecules is Gβ5-RGS7, the permanently associated heterodimer of G protein β-subunit Gβ5 and RGS7, a regulator of G protein signaling. Gβ5-RGS7 can attenuate M3R-stimulated release of Ca2+ from intracellular stores or enhance the influx of Ca2+ across the plasma membrane. Here we show that deletion of amino acids 304–345 from the central portion of the i3 loop renders M3R insensitive to regulation by Gβ5-RGS7. In addition to the i3 loop, interaction of M3R with Gβ5-RGS7 requires helix 8. According to circular dichroism spectroscopy, the peptide corresponding to amino acids 548–567 in the C-terminus of M3R assumes an α-helical conformation. Substitution of Thr553 and Leu558 with Pro residues disrupts this α-helix and abolished binding to Gβ5-RGS7. Introduction of the double Pro substitution into full-length M3R (M3RTP/LP) prevents trafficking of the receptor to the cell surface. Using atropine or other antagonists as pharmacologic chaperones, we were able to increase the level of surface expression of the TP/LP mutant to levels comparable to that of wild-type M3R. However, M3R-stimulated calcium signaling is still severely compromised. These results show that the interaction of M3R with Gβ5-RGS7 requires helix 8 and the central portion of the i3 loop. PMID:25551629

  1. Helix 8 and the i3 loop of the muscarinic M3 receptor are crucial sites for its regulation by the Gβ5-RGS7 complex.

    PubMed

    Karpinsky-Semper, Darla; Tayou, Junior; Levay, Konstantin; Schuchardt, Brett J; Bhat, Vikas; Volmar, Claude-Henry; Farooq, Amjad; Slepak, Vladlen Z

    2015-02-01

    The muscarinic M3 receptor (M3R) is a Gq-coupled receptor and is known to interact with many intracellular regulatory proteins. One of these molecules is Gβ5-RGS7, the permanently associated heterodimer of G protein β-subunit Gβ5 and RGS7, a regulator of G protein signaling. Gβ5-RGS7 can attenuate M3R-stimulated release of Ca(2+) from intracellular stores or enhance the influx of Ca(2+) across the plasma membrane. Here we show that deletion of amino acids 304-345 from the central portion of the i3 loop renders M3R insensitive to regulation by Gβ5-RGS7. In addition to the i3 loop, interaction of M3R with Gβ5-RGS7 requires helix 8. According to circular dichroism spectroscopy, the peptide corresponding to amino acids 548-567 in the C-terminus of M3R assumes an α-helical conformation. Substitution of Thr553 and Leu558 with Pro residues disrupts this α-helix and abolished binding to Gβ5-RGS7. Introduction of the double Pro substitution into full-length M3R (M3R(TP/LP)) prevents trafficking of the receptor to the cell surface. Using atropine or other antagonists as pharmacologic chaperones, we were able to increase the level of surface expression of the TP/LP mutant to levels comparable to that of wild-type M3R. However, M3R-stimulated calcium signaling is still severely compromised. These results show that the interaction of M3R with Gβ5-RGS7 requires helix 8 and the central portion of the i3 loop.

  2. 3,5,5,6,8,8-Hexamethyl-5,6,7,8-tetra­hydro-2-naphthoic acid (AHTN–COOH)

    PubMed Central

    Kuhlich, Paul; Göstl, Robert; Metzinger, Ramona; Piechotta, Christian; Nehls, Irene

    2010-01-01

    The title compound, C17H24O2, is the product of a haloform reaction of 6-acetyl-1,1,2,4,4,7-hexa­methyl­tetra­line (AHTN). The compound is a racemic mixture with a disorder in its aliphatic ring [occupany ratio 0.683 (4):0.317 (4)] due to two possible half-chair forms. The carb­oxy­lic acid unit is slightly twisted out of coplanarity with the aromatic system [dihedral angle = 29.26 (6)°]. In the crystal, pairs of short classical inter­molecular O—H⋯O hydrogen bonds link pairs of mol­ecules around a center of symmetry. PMID:21587655

  3. Study on the 8He ground state via 8He(p, d)7He and 8He(p, t)6He reaction at 82.3 MeV/nucleon

    NASA Astrophysics Data System (ADS)

    Lou, J. L.; Ye, Y. L.; Pang, D. Y.; Cao, Z. X.; Jiang, D. X.

    2013-03-01

    The differential cross sections for reactions 8He(p, d)7Heg.s and 8He(p, t)6He2+ were measured by the coincidence of d + 6 He and t + 4He in a wide angular range from 15 to 130 degree in the center-of-mass system. The cross sections of the 8He(p, t)6Heg.s reaction were extremely lower than that of 8He(p, t)6He2+ reaction, and was not obtained from the present data. The experimental results were compared to the preliminary theoretical calculations in the frame of adiabatic distorted-wave approximation with the code Fresco. The results show that the configuration of (1p3/2)2(1p1/2)2 may have some probability in the ground state wave function of 8He. The cluster structure of 8He = 5H + 3H could not be neglected.

  4. Validating Geant4 Versions 7.1 and 8.3 Against 6.1 for BaBar

    SciTech Connect

    Banerjee, Swagato; Brown, David N.; Chen, Chunhui; Cote, David; Dubois-Felsmann, Gregory P.; Gaponenko, Igor; Kim, Peter C.; Lockman, William S.; Neal, Homer A.; Simi, Gabriele; Telnov, Alexandre V.; Wright, Dennis H.; /SLAC

    2011-11-08

    Since 2005 and 2006, respectively, Geant4 versions 7.1 and 8.3 have been available, providing: improvements in modeling of multiple scattering; corrections to muon ionization and improved MIP signature; widening of the core of electromagnetic shower shape profiles; newer implementation of elastic scattering for hadronic processes; detailed implementation of Bertini cascade model for kaons and lambdas, and updated hadronic cross-sections from calorimeter beam tests. The effects of these changes in simulation are studied in terms of closer agreement of simulation using Geant4 versions 7.1 and 8.3 as compared to Geant4 version 6.1 with respect to data distributions of: the hit residuals of tracks in BABAR silicon vertex tracker; the photon and K{sub L}{sup 0} shower shapes in the electromagnetic calorimeter; the ratio of energy deposited in the electromagnetic calorimeter and the flux return of the magnet instrumented with a muon detection system composed of resistive plate chambers and limited-streamer tubes; and the muon identification efficiency in the muon detector system of the BABAR detector.

  5. Geodetic model of the 2015 April 25 Mw 7.8 Gorkha Nepal Earthquake and Mw 7.3 aftershock estimated from InSAR and GPS data

    NASA Astrophysics Data System (ADS)

    Feng, Guangcai; Li, Zhiwei; Shan, Xinjian; Zhang, Lei; Zhang, Guohong; Zhu, Jianjun

    2015-11-01

    We map the complete surface deformation of 2015 Mw 7.8 Gorkha Nepal earthquake and its Mw 7.3 aftershock with two parallel ALOS2 descending ScanSAR paths' and two ascending Stripmap paths' images. The coseismic fault-slip model from a combined inversion of InSAR and GPS data reveals that this event is a reverse fault motion, with a slight right-lateral strike-slip component. The maximum thrust-slip and right-lateral strike-slip values are 5.7 and 1.2 m, respectively, located at a depth of 7-15 km, southeast to the epicentre. The total seismic moment 7.55 × 1020 Nm, corresponding to a moment magnitude Mw 7.89, is similar to the seismological estimates. Fault slips of both the main shock and the largest aftershock are absent from the upper thrust shallower than 7 km, indicating that there is a locking lower edge of Himalayan Main Frontal Thrust and future seismic disaster is not unexpected in this area. We also find that the energy released in this earthquake is much less than the accumulated moment deficit over the past seven centuries estimated in previous studies, so the region surrounding Kathmandu is still under the threaten of seismic hazards.

  6. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on development of anuran amphibians

    SciTech Connect

    Jung, R.E.; Walker, M.K.

    1997-02-01

    The authors exposed anuran eggs and tadpoles to vehicle control (0.7% acetone) or waterborne [{sup 3}H]2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for 24 h and subsequently raised them in clean water. Neither American toads nor green frogs exhibited TCDD-related mortality, but leopard frogs showed significantly increased mortality over controls. Eggs and tadpoles eliminated TCDD relatively quickly compared with published data for other vertebrates, with t{sub {1/2}} of 1 to 5 d (American toad), 2 to 7 d (leopard frog), and 4 to 6 d (green frog). Elimination rates were slowest for tadpoles fed nothing, fastest for those fed a low-fat diet, and intermediate for those fed a high-fat diet. Although not significant, American toads exposed to {ge}0.03 {micro}g TCDD/L appeared to metamorphose earlier, and those exposed to higher TCDD treatments appeared to metamorphose at a larger body mass than controls. Comparisons of these results with studies of fish early life stages suggest that anuran eggs and tadpoles eliminate TCDD more rapidly and are 100- to 1,000-fold less sensitive to its deleterious effects during development. These differences may be related to differences in metabolic rate, patterns of lipid storage and utilization, and aryl hydrocarbon receptor binding and signal transduction.

  7. Estimates of the half-life of 2,3,7,8-tetrachlorodibenzo-p-dioxin in Vietnam veterans of operation ranch hand

    SciTech Connect

    Pirkle, J.L.; Wolfe, W.H.; Patterson, D.G.; Needham, L.L.; Philips, D.L. ); Michalek, J.E.; Miner, J.C.; Peterson, M.R. )

    1989-01-01

    A half-life of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD; commonly known as dioxin) in serum has been measured in 36 Air Force Vietnam Veterans of Operation Ranch Hand, which was the operation that aerially sprayed the herbicide Agent Orange in Vietnam. From serum specimens taken in 1982 and 1987, the median half-life of 2,3,7,8-TCDD in these Ranch Hand veterans was found to be 7.1 yr (95% confidence interval about the median of 5.8-9.6 yr). These veterans reported no civilian exposure to dioxin or herbicides. Concentrations of 2,3,7,8-TCDD in the 1982 serum specimens from these veterans ranged from 16.9 to 423 parts per trillion on a lipid weight basis. The half-life estimates were not associated with the concentration of 2,3,7,8-TCDD in the 1982 serum specimens. This half-life of 7.1 yr is much longer than the half-life of 2,3,7,8-TCDD reported in animals but is consistent with recent evidence from other human exposures to 2,3,7,8-TCDD.

  8. Pericentric inversion of chromosome 7 (inv(7) (p22q11.2)) and ring chromosome 8 (r(8) (p23q24.3)) in a girl with minor anomalies.

    PubMed Central

    Verma, R S; Conte, R A; Pitter, J H; Luke, S

    1992-01-01

    A 13 year old girl was referred with congenital microcephaly, developmental delay, a prominent nose, highly arched palate, and an apparently low set left ear. She was found to have a pericentric inversion of one chromosome 7 and a ring chromosome 8, 46,XX,inv(7) (pter----p22::q11.23----p22::q11.23----qter), r(8) (p23q24.3). The concurrence of these two abnormalities is a rare event and has not been reported previously. Images PMID:1552550

  9. FT-IR Measurements of Cross Sections of Cold C3H8 in the 7 - 15 µm for Titan

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Brown, L. R.; Toon, G. C.; Mantz, A. W.; Smith, M. A. H.

    2012-10-01

    To support atmospheric remote sensing of Titan, the absorption cross sections of N2-broadened C3H8 were obtained at temperatures between 145 and 296 K. For this, 17 spectra of pure- and N2-broadened propane were recorded in the 690 to 1550 cm-1 region using a Fourier transform spectrometer (Bruker IFS-125HR) at the Jet Propulsion Laboratory configured with a 20.38 cm long temperature-stabilized cryogenic absorption cell. The coolable cell was developed at Connecticut College and described previously [1]. We report the absorption cross sections at the various cold temperatures for nine strong propane bands (v26, v8, v21, v20, v7, v19, v18, v4, v24). In addition, we present results from ‘pseudo-line generation’, which includes positions, intensities, and effective lower state energies’ determined from high-resolution laboratory spectra, (see http://mark4sun.jpl.nasa.gov/data/spec/Pseudo/Readme). The resulting compilation will be compared to earlier work, including the C3H8+N2 spectra recorded at PNNL [2] and available line-by-line predictions [3,4]. Research described in this paper was performed at the Jet Propulsion Laboratory, and California Institute of Technology, Connecticut College, NASA Langley Research Center, under contracts and cooperative agreements with the National Aeronautics and Space Administration. References [1] K. Sung, A. W. Mantz, M. A. H. Smith, et al., J Mol Spectrosc 262, 122, 2010. [2] S. W. Sharpe, et al., Appl Spectrosc 58, 1452, 2004. [3] J. M. Flaud et al., Mol Phys 108, 699, 2010. [4] J. M. Flaud et al., J Chem Phys 114, 9361, 2001.

  10. Hepatic metabolism of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the rat and guinea pig

    SciTech Connect

    Wroblewski, V.J.; Olson, J.R.

    1985-11-01

    Marked interspecies variability exists in the acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), with the rat having an LD/sub 50/ about 25-fold greater than the guinea pig. The metabolism of TCDD was examined by incubating hepatocytes isolated from these animals with purified (/sup 14/C)TCDD (2.2 microM) for 8 hr. Over the 8-hr incubation, cytochrome P-450 content and ethoxyresorufin O-deethylase and benzphetamine N-demethylase activities were well maintained, indicating the functional viability of the hepatocytes. Quantitative differences were observed in the rate of (/sup 14/C)TCDD metabolism, with hepatocytes from control rats metabolizing TCDD at a rate 2.8-fold greater than hepatocytes from control guinea pigs. The role of the hepatic cytochrome P-450-448-dependent monooxygenase system in the metabolism of TCDD was examined through the use of hepatocytes isolated from animals pretreated with either TCDD or phenobarbital. The rate of (/sup 14/C)TCDD metabolite formation in hepatocytes from TCDD pretreated guinea pigs (0.26 +/- 0.14 pmol mg cell protein-1 hr-1) was unchanged from the control rate, while the rate in hepatocytes from TCDD pretreated rats was 3.2-fold greater than control and nine times greater than in hepatocytes from TCDD-pretreated guinea pigs. On the other hand, phenobarbital pretreatment produced little change in the rate of (/sup 14/C)TCDD metabolism in rat hepatocytes. These results suggest that TCDD may be metabolized by a TCDD inducible form of cytochrome P-448 which is expressed in the rat but not in the guinea pig.

  11. 2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents in tissues of birds at Green Bay, Wisconsin, USA

    USGS Publications Warehouse

    Jones, Paul D.; Giesy, John P.; Newsted, John L.; Verbrugge, David A.; Beaver, Donald L.; Ankley, Gerald T.; Tillitt, Donald E.; Lodge, Keith B.; Niemi, Gerald J.

    1993-01-01

    The environment has become contaminated with complex mixtures of planar, chlorinated hydrocarbons (PCHs) such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and structurally similar compounds. Because the potencies of individual congeners to cause the same adverse effects vary greatly and the relative as well as absolute concentrations of individual PCH vary among samples from different locations, it is difficult to assess the toxic effects of these mixtures on wildlife. These compounds can cause a number of adverse effects, however, because the toxic effects which occur at ecologically-relevant concentrations such as embryo-lethality and birth defects appear to be mediated through the same mechanism, the potency of individual congeners can be reported relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) which is the most toxic congener in the PCH class. The concentations of 2,3,7,8-TCDD Equivalents (TCDD-EQ) were determined in the tissues of aquatic and terrestrial birds of Green Bay, Wisconsin by the H4IIE bioassay system and compared toxic equivalency factors (TEFs) with the concentration predicted by the use of toxic equivalency factors applied to concentrations of PCH, which were determined by instrumental analyses. Concentrations of TCDD-EQ ranged from 0.52 to 440 ng/kg, wet weight. The greatest concentrations occurred in the fish-eating birds. Concentrations of TCDD-EQ, which were determined by the two methods were significantly correlated, but the additive model which used the TEFs with concentrations of measured PCB, PCDD and PCDF congeners underestimated the concentrations of TCDD-EQ measured by the H4IIE bioassay by an average of 57%. This is thought to be due to contributions from un-quantified PCH, which are known to occur in the environment. Of the quantified PCH congeners, PCDD and PCDF contributed a small portion of the TCDD-EQ in the aquatic birds, while most of the

  12. 8 CFR 246.7 - Appeals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Appeals. Pursuant to 8 CFR part 3, an appeal shall lie from a decision of an immigration judge under this part to the Board of Immigration Appeals. An appeal shall be taken within 30 days after the mailing of... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Appeals. 246.7 Section 246.7 Aliens...

  13. Absorption and luminescence characteristics of 5I7 <--> 5I8 transitions of the holmium ion in Ho3+-doped aluminosilicate preforms and fibres

    NASA Astrophysics Data System (ADS)

    Ryabochkina, P. A.; Chabushkin, A. N.; Kosolapov, A. F.; Kurkov, A. S.

    2015-02-01

    We have obtained the spectral dependences of the absorption cross sections for the Ho3+ 5I8 → 5I6 and 5I8 → 5I7 transitions in Ho3+-doped aluminosilicate fibres and the spectral dependence of the stimulated emission cross section for the Ho3+ 5I7 → 5I8 laser transition in Ho3+-doped aluminosilicate fibre preforms. The lifetime of the Ho3+ 5I7 upper laser level in the preforms has been determined.

  14. 3D-QSAR Study of 7,8-Dialkyl-1,3-diaminopyrrolo-[3,2-f] Quinazolines with Anticancer Activity as DHFR Inhibitors

    NASA Astrophysics Data System (ADS)

    Chen, Jin-can; Chen, Lan-mei; Liao, Si-yan; Qian, Li; Zheng, Kang-cheng

    2009-06-01

    A three-dimensional quantitative structure-activity relationship (3D-QSAR) study of a series of 7,8-dialkyl-1,3-diaminopyrrolo-[3,2-f] quinazolines with anticancer activity as dihydrofolate reductase (DHFR) inhibitors was carried out by using the comparative molecular field analysis (CoMFA), on the basis of our reported 2D-QSAR of these compounds. The established 3D-QSAR model has good quality of statistics and good prediction ability; the non cross-validation correlation coefficient and the cross-validation value of this model are 0.993 and 0.619, respectively, the F value is 193.4, and the standard deviation SD is 0.208. This model indicates that the steric field factor plays a much more important role than the electrostatic one, in satisfying agreement with the published 2D-QSAR model. However, the 3D-QSAR model offers visual images of the steric field and the electrostatic field. The 3D-QSAR study further suggests the following: to improve the activity, the substituent R' should be selected to be a group with an adaptive bulk like Et or i-Pr, and the substituent R should be selected to be a larger alkyl. In particular, based on our present 3D-QSAR as well as the published 2D-QSAR, the experimentally-proposed hydrophobic binding mechanism on the receptor-binding site of the DHFR can be further explained in theory. Therefore, the QSAR studies help to further understand the “hydrophobic binding" action mechanism of this kind of compounds, and to direct the molecular design of new drugs with higher activity.

  15. Serum 2,3,7,8-tetrachlorodibenzo-p-dioxin levels in Air Force health study participants - preliminary report

    SciTech Connect

    Not Available

    1988-06-24

    In 1978, the US Air Force responded to a congressional mandate to initiate an epidemiologic study of the possible health effects of exposure to herbicides and their 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) contaminants in Air Force veterans who served in the Ranch Hand defoliation operation during the Vietnam conflict. Accordingly, the Air Force conducted a nonconcurrent prospective study, the Air Force Health Study, of all 1267 members of the Ranch Hand unit and a series of matched controls. This phase of the Air Force study focused on measuring serum TCDD levels in 150 Ranch Hand veterans and 50 controls. All participants were enlisted men; the Ranch Hand veterans had been either herbicide loaders or herbicide specialists in Vietnam. The demographic and health characteristics of Ranch Hand personnel and controls were similar; however, their serum TCDD levels differed markedly.

  16. Electronic Structures of Hydrogen and Oxygen Adsorbed Tungsten (3, 2, 0) and Tungsten (8, 7, 0) Surfaces

    NASA Astrophysics Data System (ADS)

    Bao, Zhuo; Bostwick, Aaron; Rotenberg, Eli; Kevan, Stephen

    2011-03-01

    The Valence band electronic structues of Hydrogen adsorbed and Oxygen adsorbed Tungsten stepped surfaces, Tungsten (3, 2, 0) and (8, 7, 0) surface are investigated using angular-resolved photoemission techniques and ab-initio electronic structure calculation methods. The band features of surface states at different Hydrogen and Oxygen coverages are experimentally distinguished by using photon-energy scanning method. Quasi-one- dimensional band features are found in the surface states with saturated Oxygen coverages of both stepped surfaces. The effects of adsorbate coverages on dimensionalities of surface electronic states are studied using high-resolution band mapping methods and ab-initio calculation methods. Thanks to Department of Energy for the financial supporting of this project.

  17. An analytical and experimental investigation of a 1.8 by 3.7 meter Fresnel lens solar concentrator

    NASA Technical Reports Server (NTRS)

    Hastings, L. J.; Allums, S. L.; Jensen, W. S.

    1977-01-01

    Line-focusing acrylic Fresnel lenses with application potential in the 200 to 370 C range are being analytically and experimentally evaluated. Investigations previously conducted with a 56 cm wide lens have been extended by the present study to experimentation/analyses with a 1.8 by 3.7 m lens. A measured peak concentration ratio of 64 with 90 percent of the transmitted energy focused into a 5.0 cm width was achieved. A peak concentration of 61 and a 90 percent target width of 4.5 cm were analytically computed. The experimental and analytical lens transmittance was 81 percent and 86 percent, respectively. The lens also was interfaced with a receiver assembly and operated in the collection mode. The collection efficiency ranged from 42 percent at 100 C to 26 percent at 300 C.

  18. Turtle sex determination assay: Mass balance and responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin and 3,3',4,4',5-pentachlorobiphenyl

    USGS Publications Warehouse

    Gale, Robert W.; Bergeron, Judith M.; Willingham, Emily J.; Crews, David

    2002-01-01

    Polyhalogenated hydrocarbons have been implicated in the anomalous sexual differentiation of mammals and reptiles. Here, a temperature-sensitive turtle sex determination assay using the red-eared slider (Trachemys scripta elegans) was used to determine the estrogenic or antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB-126). Neither TCDD nor PCB-126 showed a statistically significant difference in the resulting sex ratios (Fisher's exact test, p < 0.45). As a consequence of the dosing technique (eggshell spotting), the shell retained 90 and 96% of the dose for PCB-126 and TCDD, respectively, similar to retention of estradiol-17β. However, the dosing allowed transfer of sufficient chemical to achieve tissue concentrations that were greater than most concentrations reported for environmentally incurred residues. Similar relative mass distributions of PCB-126 and TCDD were observed in albumin (14–20%), yolk (55–70%), and embryo (16–25%). Relative concentration distributions in the embryo approached those in the yolk, 37 to 40% and 40 to 52%, respectively, while relative concentrations in the albumin remained at 11 to 20%. Lipid-normalized TCDD and PCB-126 concentrations were 30- to 40-fold greater in the embryo than in the yolk. It is hypothesized that nonpassive partitioning processes may have occurred in the embryo.

  19. [Effect of Cynaropicrin on 2,3,4,7,8-Pentachlorodibenzofuran-induced Wasting Syndrome and Oxidative Stress].

    PubMed

    Yamada, Ken-ichi; Ishii, Yuji; Takeda, Tomoki; Kuroki, Hiroaki; Mitoma, Chikage; Uchi, Hiroshi; Furue, Masutaka; Yamada, Hideyuki

    2015-05-01

    The effect of cynaropicrin that is the major component of an edible plant, artichoke (Cynara scolymus) on 2,3,4,7,8-pentachlorodibenzofuran (PenCDF)-induced toxicity in mice was studied. We evaluated the effect of cynaropicrin on the wasting syndrome and oxidative stress elicited by PenCDF. However, the PenCDF dose-response relationship on the wasting syndrome has been superficial. Therefore, we determined the dose which causes wasting syndrome in C57BL/6J mice, a responsive strain to dioxins. Since 2,3,7,8-tetrachlorodibenzo-p-dioxin (0.1 mg/kg, p.o.) induces hepatic ethoxyresorfin O-deethylase (EROD) activity in mice, we set the doses of PenCDF at 0.3, 1.0, 3.0, 5.0 and 10 mg/kg (once, p.o.) on the basis of its toxic-eqivalency factor (0.3). The wasting syndrome was evaluated by measuring the daily changes of body weight. Thiobarbituric acid-reactive substances were used as an index of oxidative stress. Of PenCDF doses examined, wasting syndrome and oxidative stress took place most markedly in 5 mg/kg. In disagreement with this, EROD activity which is the marker of the aryl hydrocarbon receptor-dependent induction of cytochrome P450 1a1 was elevated most abundantly at 0.3 mg/kg. Then, we examined the effect of cynaropicrin on the wasting syndrome and oxidative stress provoked by PenCDF at 5 mg/kg. However, this compound up to 20 mg/kg (p.o.) did not attenuate PenCDF-induced wasting syndrome. On the contray, PenCDF-induced oxidateive stress was suppressed by cynaropicrin at the highest dose (20 mg/kg), although EROD activity was increased rather than reduced by cynaropicrin at lower doses. Thus, it is suggested that cynaropicrin has an ability to reduce oxidative stress caused by PenCDF. PMID:26226680

  20. Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to embryos of the fathead minnow (Pimephales promelas, Rafinesque)

    SciTech Connect

    Olivieri, C.; Cooper, K.

    1995-12-31

    This study correlates the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) residue and its toxicity to the fathead minnow embryo exposed to levels lower than the TCDD solubility range. The TCDD tissue doses in the embryo/larvae were related to gross lesions, delayed hatching, and death. A 7-day bioconcentration factor on a lipid basis (BCF{sub L}) was calculated. Embryos at the blatsula stage were exposed to [{sup 3}H] TCDD water concentrations (0.37, 0.59, 1.2, 2.83, and 10.1 6 ng/L), a nontreatment control and a solvent carrier control. Lesions were qualified as mild and severe based on their onset and their pathogenesis. Thus, mild lesions developed just prior to hatching or post-hatching at the fifth day of development. The severe lesions appeared at the third day of development. Embryos with tissue doses {le}2.46 {+-} 1.34 ng/g consistently developed mild lesions, while embryos with tissue doses {ge} 12.07 {+-} 4.91 ng/g developed severe lesions. The lowest observable adverse effect level was 0.04 {+-} 0.02 ng/g. The calculated 7-day ED{sub 50} was 0.14 ng/g. There was no delayed hatching at any of the concentrations tested. Embryo death occurred at a tissue concentration {ge}2.46 ng/g. The calculated 7-day LD{sub 50} was 25.71 ng/g. The relationship between the concentration of TCDD in the water (x = ng/L) and in the tissue dose (y = ng/g) fitted a linear curve y = {minus}1,143 + 3,792.5x, r{sup 2} = 0.98. The calculated BCF{sub L} (wet weight) was dose dependent. Embryos with tissue doses of 0.04 and 0.16 ng/g had BCF{sub L} of 2,700 and 3,325, respectively. Embryos with tissue doses of 2.46, 12.07, and 37.07 ng/g, had a BCF{sub L} of 104,225, 106,625 and 91,075, respectively.

  1. Immunotoxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in a complex environmental mixture from the Love Canal.

    PubMed

    Silkworth, J B; Cutler, D S; Sack, G

    1989-02-01

    The organic phase of the leachate (OPL) from the Love Canal chemical dump site contains more than 100 organic compounds including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The immunotoxic potential of OPL was determined in two mouse strains which differ in their sensitivity to aromatic hydrocarbon (Ah) receptor-mediated toxicity. OPL was administered in corn oil in a single oral gavage to male BALB/cByJ (Ahb/Ahb) mice (0.5, 0.8, or 1.1 g/kg) and DBA/2J (Ahd/Ahd) mice (0.6, 0.9, or 1.3 g/kg). TCDD was similarly administered at 0.25, 1.0, 4.0, or 16.0 micrograms/kg. Two days later all mice were immunized with sheep erythrocytes (SRBC). The antibody response (PFC) and organ weights were evaluated 4 days later. OPL produced thymic atrophy and hepatomegaly in both strains at all dose levels. The PFC/spleen in BALB/cByJ mice was significantly reduced at the three doses to 34, 13, and 15%, respectively, of the control response. Serum anti-SRBC antibody levels and relative spleen weights were also reduced. The only immune effect in the DBA/2J mice was a decrease of the PFC/spleen to 58% of the control at the highest dose. TCDD decreased the relative thymus and spleen weights only in BALB/cByJ mice. However, TCDD produced hepatomegaly, a decrease in serum antibody, and a decrease in PFC/spleen in both BALB/cByJ and DBA/2J mice to 3 and 15%, respectively, at 16 micrograms/kg. Thus, the TCDD dose required to cause a 50% suppression (ED50) of PFC/spleen for the BALB/cByJ and DBA/2J strains was 1.84 and 3.89 micrograms/kg, respectively. The ED50 for OPL was 0.24 g/kg in BALB/cByJ mice. The TCDD concentration in the OPL was estimated to be 7.6 ppm, which agrees closely with the chemical analysis (3 ppm). The results suggest that the immunosuppression caused by OPL in BALB/cByJ mice was primarily due to TCDD, that the non-TCDD components of OPL diminished the TCDD immunotoxicity in the DBA/2J strain, and that the thymic atrophy and hepatomegaly were caused primarily by the non

  2. Immunotoxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in a complex environmental mixture from the Love Canal

    SciTech Connect

    Silkworth, J.B.; Cutler, D.S.; Sack, G.

    1989-02-01

    The organic phase of the leachate (OPL) from the Love Canal chemical dump site contains more than 100 organic compounds including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The immunotoxic potential of OPL was determined in two mouse strains which differ in their sensitivity to aromatic hydrocarbon (Ah) receptor-mediated toxicity. OPL was administered in corn oil in a single oral gavage to male BALB/cByJ (Ahb/Ahb) mice (0.5, 0.8, or 1.1 g/kg) and DBA/2J (Ahd/Ahd) mice (0.6, 0.9, or 1.3 g/kg). TCDD was similarly administered at 0.25, 1.0, 4.0, or 16.0 micrograms/kg. Two days later all mice were immunized with sheep erythrocytes (SRBC). The antibody response (PFC) and organ weights were evaluated 4 days later. OPL produced thymic atrophy and hepatomegaly in both strains at all dose levels. The PFC/spleen in BALB/cByJ mice was significantly reduced at the three doses to 34, 13, and 15%, respectively, of the control response. Serum anti-SRBC antibody levels and relative spleen weights were also reduced. The only immune effect in the DBA/2J mice was a decrease of the PFC/spleen to 58% of the control at the highest dose. TCDD decreased the relative thymus and spleen weights only in BALB/cByJ mice. However, TCDD produced hepatomegaly, a decrease in serum antibody, and a decrease in PFC/spleen in both BALB/cByJ and DBA/2J mice to 3 and 15%, respectively, at 16 micrograms/kg. Thus, the TCDD dose required to cause a 50% suppression (ED50) of PFC/spleen for the BALB/cByJ and DBA/2J strains was 1.84 and 3.89 micrograms/kg, respectively. The ED50 for OPL was 0.24 g/kg in BALB/cByJ mice. The TCDD concentration in the OPL was estimated to be 7.6 ppm, which agrees closely with the chemical analysis (3 ppm).

  3. Teratology of 2,3,7,8-tetrachlorodibenzo-p-dioxin in a complex environmental mixture from the Love Canal

    SciTech Connect

    Silkworth, J.B.; Cutler, D.S.; Antrim, L.; Houston, D.; Tumasonis, C.; Kaminsky, L.S. )

    1989-07-01

    The organic phase of a leachate (OPL) from the Love Canal chemical dump site contains more than 100 organic compounds including 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD). The teratogenic potential of OPL was determined in two inbred and one hybrid mouse strain which differ in their sensitivity to aromatic hydrocarbon (Ah) receptor-mediated toxicity. OPL was orally administered in corn oil on Days 6-15 of gestation to C57BL/6J mice (Ahb/Ahb) at doses of 0, 0.1, 0.3, 0.5, and 0.7 g kg-1 day-1 and to DBA/2J (Ahd/Ahd) females, which were mated with either DBA/2J or C57BL/6J males, at 0, 0.5, 1, and 2.0 g kg-1 day-1. In C57BL/6J mice, which express a high-affinity Ah receptor that avidly binds TCDD, the ED50's of OPL for cleft palate and hydronephrosis were 0.44 and 0.11 g OPL kg-1 day-1, respectively. Maternal mortality was 5% at the highest dose. In DBA/2J fetuses, which express a low-affinity receptor, neither treatment-related cleft palate nor hydronephrosis was induced by dose levels that caused 36% maternal mortality. In hybrid D2B6F1 fetuses, the incidence of cleft palate reached only 8% at 2 g OPL kg-1 day-1 but the ED50 for hydronephrosis was 0.76 g OPL kg-1 day-1. TCDD was similarly administered to pregnant C57BL/6J mice at 0, 0.5, 1, 2, and 4 micrograms kg-1 day-1 and to DBA/2J mice at 0, 0.5, 2, 4, and 8 micrograms kg-1 day-1. In C57BL/6J fetuses, the ED50's for cleft palate and hydronephrosis were 4.6 and 0.73 microgram TCDD kg-1 day-1, respectively. In DBA/2J fetuses the ED50's for cleft palate and hydronephrosis were 15.0 and 6.4 micrograms TCDD kg-1 day-1, respectively. Both the OPL and TCDD caused maternal hepatomegaly and thymic atrophy in all strains, but increased only C57BL/6J fetal weights. OPL decreased the number of fetuses per C57BL/6J dam at the two highest doses but there were no other reproductive effects in any of the groups.

  4. 3,3,6,6,9,9-Hexaethyl-1,2,4,5,7,8-hexaoxacyclononane at 296 K.

    PubMed

    Cerna, Jorge; Bernès, Sylvain; Cañizo, Adriana; Eyler, Nora

    2009-11-01

    The title molecule (diethyl ketone triperoxide, DEKTP), C(15)H(30)O(6), is a cyclic triperoxide closely related to triacetone triperoxide (TATP), one of the most unstable explosives known. However, the stability of DEKTP is ca 20-50 times greater than that of TATP. DEKTP crystallizes with two molecules in the asymmetric unit, with virtually identical geometry. The cyclononane core is stabilized in a twisted boat-chair conformation (approximate D(3) symmetry), very close to that previously described for TATP. The explanation for the safe thermal behaviour of DEKTP compared with TATP should thus not be sought in the molecular dimensions, but rather in the thermal decomposition kinetics. PMID:19893236

  5. Synthesis, structures, electrochemical studies and antioxidant activity of 5-aryl-4-oxo-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine-7-carboxylic acids

    NASA Astrophysics Data System (ADS)

    Quiroga, Jairo; Romo, Pablo E.; Ortiz, Alejandro; Isaza, José Hipólito; Insuasty, Braulio; Abonia, Rodrigo; Nogueras, Manuel; Cobo, Justo

    2016-09-01

    The synthesis of 5-aryl-4-oxo-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine-7-carboxylic acids 3 from the reaction of 6-aminopyrimidines 1 with arylidene derivatives of pyruvic acid 2 under microwave and ultrasound irradiation is described. The orientation of cyclization process was determined by NMR measurements. The methodology provides advantages such as high yields and friendly to the environment without the use of solvents. The antioxidant properties, DPPH free radical scavenging, ORAC, and anodic potential oxidation of the new pyridopyrimidines were studied.

  6. 1,5-Dichloro-3(2,7),7(2,7)-dinaphthal-ena-2,4,6,8-tetra-oxa-1(2,6),5(2,6)-di(1,3,5-triazina)octa-phane.

    PubMed

    Sang, Qiu-Guang; Yang, Jing-Kui

    2011-09-01

    In the macrocyclic title compound, C(26)H(12)Cl(2)N(6)O(4), an O-atom-bridged calix[2]naphthalene-[2]triazine synthesized using a one-pot approach from naphthalene-2,7-diol and cyanuric chloride, the two isolated naphthalene planes and the two triazine-2,6-di-oxy planes adopt a 1,3-alternate configuration, with a dihedral angle of 84.10 (8)° between the naphthalene rings and a dihedral angle of 39.02 (14)° between the triazine rings. In the crystal, weak inter-molecular π-π stacking inter-actions are found between face-to-face naphthalene rings [centroid-centroid distance = 3.662 (7) Å].

  7. Line-of-sight displacement from ALOS-2 interferometry: Mw 7.8 Gorkha Earthquake and Mw 7.3 aftershock

    NASA Astrophysics Data System (ADS)

    Lindsey, Eric O.; Natsuaki, Ryo; Xu, Xiaohua; Shimada, Masanobu; Hashimoto, Manabu; Melgar, Diego; Sandwell, David T.

    2015-08-01

    Interferometric synthetic aperture radar (InSAR) is a key tool for the analysis of displacement and stress changes caused by large crustal earthquakes, particularly in remote areas. A challenge for traditional InSAR has been its limited spatial and temporal coverage especially for very large events, whose dimensions exceed the typical swath width of 70-100 km. This problem is addressed by the ALOS-2 satellite, whose PALSAR-2 instrument operates in ScanSAR mode, enabling a repeat time of 2 weeks and a swath width of 350 km. Here we present InSAR line-of-sight displacement data from ALOS-2/PALSAR-2 observations covering the Mw 7.8 Gorkha, Nepal earthquake and its Mw 7.3 aftershock that were acquired within 1 week of each event. The data are made freely available and we encourage their use in models of the fault slip and associated stress changes. The Mw 7.3 aftershock not only extended the rupture area of the main shock toward the east but also left a 20 km gap where the fault has little or no coseismic slip. We estimate this unslipped fault patch has the potential to generate a Mw 6.9 event.

  8. Atg8 Transfer from Atg7 to Atg3: A Distinctive E1-E2 Architecture and Mechanism in the Autophagy Pathway

    SciTech Connect

    Taherbhoy, Asad M.; Tait, Stephen W.; Kaiser, Stephen E.; Williams, Allison H.; Deng, Alan; Nourse, Amanda; Hammel, Michal; Kurinov, Igor; Rock, Charles O.; Green, Douglas R.; Schulman, Brenda A.

    2012-07-11

    Atg7 is a noncanonical, homodimeric E1 enzyme that interacts with the noncanonical E2 enzyme, Atg3, to mediate conjugation of the ubiquitin-like protein (UBL) Atg8 during autophagy. Here we report that the unique N-terminal domain of Atg7 (Atg7{sup NTD}) recruits a unique 'flexible region' from Atg3 (Atg3{sup FR}). The structure of an Atg7{sup NTD}-Atg3{sup FR} complex reveals hydrophobic residues from Atg3 engaging a conserved groove in Atg7, important for Atg8 conjugation. We also report the structure of the homodimeric Atg7 C-terminal domain, which is homologous to canonical E1s and bacterial antecedents. The structures, SAXS, and crosslinking data allow modeling of a full-length, dimeric (Atg7 {approx} Atg8-Atg3){sub 2} complex. The model and biochemical data provide a rationale for Atg7 dimerization: Atg8 is transferred in trans from the catalytic cysteine of one Atg7 protomer to Atg3 bound to the N-terminal domain of the opposite Atg7 protomer within the homodimer. The studies reveal a distinctive E1 {approx} UBL-E2 architecture for enzymes mediating autophagy.

  9. Species differences in 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity and biotransformation in fish

    SciTech Connect

    Kleeman, J.M.; Olson, J.R.; Peterson, R.E.

    1988-02-01

    Rainbow trout, yellow perch, carp, bluegill, largemouth bass, and bullhead were treated with graded doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 1, 5, 25, or 125 micrograms/kg) or vehicle, ip. The lethal potency of TCDD tended to be greater in yellow perch, carp, and bullhead than in the other three species (LD50 80 days post-treatment, 3-5 versus 10-16 micrograms/kg, respectively). All species treated with the highest dose of TCDD (125 micrograms/kg) displayed a latency period of 1-4 weeks prior to death; longer latency periods were produced by lower lethal doses. Effects of TCDD treatment on body weight were both species-dependent and dose-dependent. Fin necrosis was observed in all fish species; however, cutaneous hemorrhage was observed only in TCDD-treated perch, carp, and bluegill, and cutaneous hyperpigmentation only in TCDD-treated carp and largemouth bass. Gallbladder bile was analyzed for TCDD and its metabolites 7 days after fish were injected with (/sup 14/C)TCDD (60 micrograms/kg, ip). At least three TCDD metabolites in addition to the parent compound were found in the gallbladder bile of all six species. In addition, the retention time of the major biliary TCDD metabolite (determined by HPLC) was similar in all species except yellow perch. Beta-Glucuronidase treatment of the bile from largemouth bass and bluegill suggested that at least two of the TCDD metabolites were glucuronide conjugates. Thus, species differences exist in the lethal potency, signs of overt toxicity, and biotransformation of TCDD among freshwater fish.

  10. 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in extracts of Baltic white-tailed sea eagles

    SciTech Connect

    Koistinen, J.; Giesy, J.P.; Koivusaari, J.; Nuuja, I.; Vuorinen, P.J.; Paasivirta, J.

    1997-07-01

    Concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin-(TCDD) equivalents were measured in extracts of Baltic white-tailed sea eagle tissues. Extracts of salmon, ringed seal, and grey seal were analyzed as other predatory species of the same area. Concentrations in eagle and seal tissues were greater than those in salmon. Concentrations of TCDD equivalents (TCDD-EQs) determined by the H4IIE bioassay were compared with toxic equivalents (TEQs) derived from instrumental chemical analyses in fractions containing polychlorinated dibenzo-P-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) or coplanar polychlorinated biphenyls (PCBs). Toxic equivalents were calculated by use of an additive model in which the product of the concentrations of instrumentally measured individual congeners were multiplied by their TCDD equivalency factors and were summed to give a total concentration of TEQs. The TCDD-EQs were compared with TEQs to develop a mass balance to determine whether all the TCDD-like activity was accounted for. The TEQs determined by chemical analyses for coplanar PCBs was 770 pg/g fw, and that of PCDD/PCDFs was 270 pg/g fw in this eagle. Thus, concentrations of TCDD-EQs were approx. 20% greater than those of TEQs. The true difference in activities is probably greater because of lower recoveries and infra-additivities among congeners in the bioassay. This indicates that there are compounds present in the extracts that can contribute to the total concentrations of TCDD-EQs in white-tailed sea eagle eggs to the no-observable-adverse-effect concentration, ranged from 7.3 to 141. This indicates that current concentrations of TCDD-EQs in these eggs are likely causing adverse effects in the Baltic populations of white-tailed sea eagles. This study indicated that the H4IIE bioassay is useful for monitoring the presence and biological activity of TCDD-like compounds in environmental samples like white-tailed sea eagles.

  11. 2,3,7,8-TCDD toxic equivalents in Great Lakes salmon derived using mammalian, bird, and fish cell bioassays

    SciTech Connect

    Heuvel, M.R. van den; Clemons, J.H.; Bols, N.C.; Dixon, D.G.; Kennedy, S.W.; Metcalfe, T.L.; Smith, I.R.

    1994-12-31

    Chinook salmon from lakes Ontario and Huron, and Coho salmon from lakes Ontario and Erie were captured during their fall spawning migration. Subsamples of extracted pooled muscle, liver and egg tissue were used to measure congener specific PCBs, chlorinated dioxins and furans as well as bioassay derived 2,3,7,8-TCDD toxic equivalent concentration (TEC). The cell culture bioassays used to measure TECs were rat hepatoma (H411E) and rainbow trout hepatocyte (RTL-W1) continuous cell lines as well as chicken embryo hepatocyte primary culture (CEH). Although excellent correlations were found between all 3 cell culture bioassays, CEH was found to be 10 times and 30 times more sensitive than H411E and RTL-W1 respectively. Lake Ontario TECs were found to be higher than either Lake Huron or Lake Erie samples for both species of Salmon, and Chinook salmon was elevated over Coho Salmon. Chemical data indicates that the more toxic coplanar PCBs are selectively concentrated in eggs as compared to liver and muscle. Bioassay derived TECs are discussed with regard to chemical contribution of the PCB and dioxin/furan congeners based on an additive model.

  12. Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to brook trout (salvelinus fontinalis) during early development

    SciTech Connect

    Walker, M.K.; Peterson, R.E. )

    1994-05-01

    The sensitivity of early life stages of brook trout (Salvelinus fontinalis) to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity was investigated. Newly fertilized eggs were exposed for 48 h to water containing either acetone or a range of concentrations of [[sup 3]H]TCDD dissolved in acetone. Eggs were then transferred to TCDD-free water and observed through development. TCDD concentrations of 101 to 470 pg/g in the eggs caused dose-related increases in sac-fry mortality associated with yolk-sac edema, hemorrhages, and arrested development. These signs of TCDD-induced toxicity resemble blue-sac disease. The NOELs and LOELs for sac-fry mortality were 135 and 185 pg TCDD/g egg, respectively, whereas the LD50 and LD100 were 200 and 324 pg/g egg, respectively. The time course and signs of TCDD toxicity to brook trout during early development are essentially identical to those observed in both rainbow trout and lake trout following TCDD exposure of their eggs via water or injection, and in lake trout exposed to maternally derived TCDD. Brook trout sac fry are intermediate in sensitivity to TCDD-induced lethality compared to lake trout and rainbow trout.

  13. 2,3,7,8-tetrachlorodibenzo-p-dioxin induced autophagy in a bovine kidney cell line.

    PubMed

    Fiorito, Filomena; Ciarcia, Roberto; Granato, Giovanna Elvira; Marfe, Gabriella; Iovane, Valentina; Florio, Salvatore; De Martino, Luisa; Pagnini, Ugo

    2011-12-18

    The administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to a variety of cultured cells may alter their ability to proliferate and die. In a previous study we demonstrated that TCDD induced proliferation in Madin-Darby Bovine Kidney (MDBK) cells where no signs of apoptosis were observed, but herein, analysis of MDBK cell morphology, in a large number of exposed cells, revealed some alterations, as expanded cytoplasm, an increase of intercellular spaces and many pyknotic nuclei. Hence, the aim of the current study was to elucidate the influences of dioxin on cell proliferation and cell death. We found that dioxin increased proliferation, as well as, activated cell death with autophagy, as we detected by increased amount of LC3-II, an autophagosome marker. Furthermore, formation of acidic vesicular organelles was observed by fluorescence microscopy following staining with the lysosomotropic agent acridine orange. These results were accompanied by down-regulation of telomerase activity, bTERT and c-Myc. Key tumor-suppressor protein p53 and expression of cell cycle inhibitor p21Waf1/Cip1 were activated after TCDD exposure. These changes occurred with activation of ATM phosphorylation in the presence of a decrease in Mdm2 protein levels. Taken together, these results support the idea that TCDD in MDBK cells, may exert its action, in part, by enhancing cell proliferation, but also by modulating the incidence of induced cell death with autophagy.

  14. Discovery and Rational Design of Pteridin-7(8H)-one-Based Inhibitors Targeting FMS-like Tyrosine Kinase 3 (FLT3) and Its Mutants.

    PubMed

    Sun, Deheng; Yang, Yu; Lyu, Jiankun; Zhou, Wei; Song, Wenlin; Zhao, Zhenjiang; Chen, Zhuo; Xu, Yufang; Li, Honglin

    2016-07-14

    FLT3 has been validated as a therapeutic target for the treatment of acute myeloid leukemia (AML). In this paper, we describe for the first time, pteridin-7(8H)-one as a scaffold for potent FLT3 inhibitors derived from structural optimizations on irreversible EGFR inhibitors. The representative inhibitor (31) demonstrates single-digit nanomolar inhibition against FLT3 and subnanomolar KD for drug-resistance FLT3 mutants. In profiling of the in vitro tumor cell lines, it shows good selectivity against AML cells harboring FLT3-ITD mutations over other leukemia and solid tumor cell lines. The mechanism of action study illustrates that pteridin-7(8H)-one derivatives suppress the phosphorylation of FLT3 and its downstream pathways, thereby inducing G0/G1 cell cycle arrest and apoptosis in AML cells. In in vivo studies, 31 significantly suppresses the tumor growth in MV4-11 xenograft model. Overall, we provide a structurally distinct chemical scaffold with which to develop FLT3 mutants-selective inhibitors for AML treatment.

  15. Crystal structure of (1S,3R,8R,9R)-2,2-di-chloro-3,7,7-tri-methyl-10-methylenetri-cyclo-[6.4.0.0(1,3)]dodecan-9-ol.

    PubMed

    Benzalim, Ahmed; Auhmani, Aziz; Bimoussa, Abdoullah; Ait Itto, My Youssef; Daran, Jean-Claude; Auhmani, Abdelwahed

    2016-08-01

    The title compound, C16H24Cl2O, was synthesized by treating (1S,3R,8S,9R,10S)-2,2-di-chloro-3,7,7,10-tetra-methyl-9,10-ep-oxy-tri-cyclo-[6.4.0.0(1,3)]dodecane with a concentrated solution of hydro-bromic acid. It is built up from three fused rings: a cyclo-heptane ring, a cyclo-hexyl ring bearing alkene and hy-droxy substituents, and a cyclo-propane ring bearing two chlorine atoms. The asymmetric unit contains two mol-ecules linked by an O-H⋯O hydrogen bond. In the crystal, further O-H⋯O hydrogen bonds build up an R 4 (4)(8) cyclic tetra-mer. One of the mol-ecules presents disorder that affects the seven-membered ring. In both mol-ecules, the six-membered rings display a chair conformation, whereas the seven-membered rings display conformations inter-mediate between boat and twist-boat for the non-disordered mol-ecule and either a chair or boat and twist-boat for the disordered mol-ecule owing to the disorder. The absolute configuration for both mol-ecules is 1S,3R,8R,9R and was deduced from the chemical pathway and further confirmed by the X-ray structural analysis. PMID:27536404

  16. Transcriptional profiling of rat white adipose tissue response to 2,3,7,8-tetrachlorodibenzo-ρ-dioxin.

    PubMed

    Houlahan, Kathleen E; Prokopec, Stephenie D; Sun, Ren X; Moffat, Ivy D; Lindén, Jere; Lensu, Sanna; Okey, Allan B; Pohjanvirta, Raimo; Boutros, Paul C

    2015-10-15

    Polychlorinated dibenzodioxins are environmental contaminants commonly produced as a by-product of industrial processes. The most potent of these, 2,3,7,8-tetrachlorodibenzo-ρ-dioxin (TCDD), is highly lipophilic, leading to bioaccumulation. White adipose tissue (WAT) is a major site for energy storage, and is one of the organs in which TCDD accumulates. In laboratory animals, exposure to TCDD causes numerous metabolic abnormalities, including a wasting syndrome. We therefore investigated the molecular effects of TCDD exposure on WAT by profiling the transcriptomic response of WAT to 100μg/kg of TCDD at 1 or 4days in TCDD-sensitive Long-Evans (Turku/AB; L-E) rats. A comparative analysis was conducted simultaneously in identically treated TCDD-resistant Han/Wistar (Kuopio; H/W) rats one day after exposure to the same dose. We sought to identify transcriptomic changes coinciding with the onset of toxicity, while gaining additional insight into later responses. More transcriptional responses to TCDD were observed at 4days than at 1day post-exposure, suggesting WAT shows mostly secondary responses. Two classic AHR-regulated genes, Cyp1a1 and Nqo1, were significantly induced by TCDD in both strains, while several genes involved in the immune response, including Ms4a7 and F13a1 were altered in L-E rats alone. We compared genes affected by TCDD in rat WAT and human adipose cells, and observed little overlap. Interestingly, very few genes involved in lipid metabolism exhibited altered expression levels despite the pronounced lipid mobilization from peripheral fat pads by TCDD in L-E rats. Of these genes, the lipolysis-associated Lpin1 was induced slightly over 2-fold in L-E rat WAT on day 4.

  17. Pulmonary bioavailability and fine particle enrichment of 2,3,7,8-tetrachlorodibenzo-p-dioxin in respirable soil particles

    SciTech Connect

    Nessel, C.S.; Amoruso, M.A.; Umbreit, T.H.; Meeker, R.J.; Gallo, M.A. )

    1992-08-01

    The pulmonary bioavailability of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the enrichment of polychlorinated dioxins (PCDDs) and furans (PCDFs) in fine particles were evaluated to assess the implications that these factors have on risk and exposure assessments. Respirable subfractions of PCDD-contaminated soil from a former 2,4,5-trichlorophenoxyacetic acid manufacturing site were isolated by chemical dispersion and gravity sedimentation. Analysis of the subfractions revealed that there was a size-dependent enrichment of PCDDs and PCDFs, with smaller particles more highly contaminated. TCDD was enriched up to 33-fold as compared to unfractionated soil. Soil and laboratory-recontaminated gallium oxide, which served as the positive control, were administered by intratracheal instillation to female Sprague-Dawley rats. Animals were terminated up to 28 days following treatment and pulmonary bioavailability of TCDD was assessed by hepatic enzyme induction and TCDD concentration. Enzyme induction was dependent on the duration of exposure with up to 56 and 918% increases in cytochrome P450 and aryl hydrocarbon hydroxylase (AHH) activity, respectively, following exposure to PCDD-contaminated soil. There was no significant difference in AHH induction between animals which received contaminated soil and those treated with the positive control. Hepatic concentration of TCDD in soil-exposed rats was 115, 101, and 179% of positive controls at 1, 7, and 28 days post-treatment, suggesting that the soil or cocontaminants influenced retention of TCDD in the liver. These data indicate that the relative pulmonary bioavailability of TCDD on respirable soil particles is 100% as compared to laboratory-recontaminated gallium oxide and that PCDDs and PCDFs are highly enriched on respirable particles.

  18. Teratology of 2,3,7,8-tetrachlorodibenzo-p-dioxin in a complex environmental mixture from the love canal.

    PubMed

    Silkworth, J B; Cutler, D S; Antrim, L; Houston, D; Tumasonis, C; Kaminsky, L S

    1989-07-01

    The organic phase of a leachate (OPL) from the Love Canal chemical dump site contains more than 100 organic compounds including 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD). The teratogenic potential of OPL was determined in two inbred and one hybrid mouse strain which differ in their sensitivity to aromatic hydrocarbon (Ah) receptor-mediated toxicity. OPL was orally administered in corn oil on Days 6-15 of gestation to C57BL/6J mice (Ahb/Ahb) at doses of 0, 0.1, 0.3, 0.5, and 0.7 g kg-1 day-1 and to DBA/2J (Ahd/Ahd) females, which were mated with either DBA/2J or C57BL/6J males, at 0, 0.5, 1, and 2.0 g kg-1 day-1. In C57BL/6J mice, which express a high-affinity Ah receptor that avidly binds TCDD, the ED50's of OPL for cleft palate and hydronephrosis were 0.44 and 0.11 g OPL kg-1 day-1, respectively. Maternal mortality was 5% at the highest dose. In DBA/2J fetuses, which express a low-affinity receptor, neither treatment-related cleft palate nor hydronephrosis was induced by dose levels that caused 36% maternal mortality. In hybrid D2B6F1 fetuses, the incidence of cleft palate reached only 8% at 2 g OPL kg-1 day-1 but the ED50 for hydronephrosis was 0.76 g OPL kg-1 day-1. TCDD was similarly administered to pregnant C57BL/6J mice at 0, 0.5, 1, 2, and 4 micrograms kg-1 day-1 and to DBA/2J mice at 0, 0.5, 2, 4, and 8 micrograms kg-1 day-1. In C57BL/6J fetuses, the ED50's for cleft palate and hydronephrosis were 4.6 and 0.73 microgram TCDD kg-1 day-1, respectively. In DBA/2J fetuses the ED50's for cleft palate and hydronephrosis were 15.0 and 6.4 micrograms TCDD kg-1 day-1, respectively. Both the OPL and TCDD caused maternal hepatomegaly and thymic atrophy in all strains, but increased only C57BL/6J fetal weights. OPL decreased the number of fetuses per C57BL/6J dam at the two highest doses but there were no other reproductive effects in any of the groups. It was concluded that the OPL is teratogenic and that hydronephrosis is a sensitive measure of TCDD toxicity in a

  19. Teratology of 2,3,7,8-tetrachlorodibenzo-p-dioxin in a complex environmental mixture from the love canal.

    PubMed

    Silkworth, J B; Cutler, D S; Antrim, L; Houston, D; Tumasonis, C; Kaminsky, L S

    1989-07-01

    The organic phase of a leachate (OPL) from the Love Canal chemical dump site contains more than 100 organic compounds including 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD). The teratogenic potential of OPL was determined in two inbred and one hybrid mouse strain which differ in their sensitivity to aromatic hydrocarbon (Ah) receptor-mediated toxicity. OPL was orally administered in corn oil on Days 6-15 of gestation to C57BL/6J mice (Ahb/Ahb) at doses of 0, 0.1, 0.3, 0.5, and 0.7 g kg-1 day-1 and to DBA/2J (Ahd/Ahd) females, which were mated with either DBA/2J or C57BL/6J males, at 0, 0.5, 1, and 2.0 g kg-1 day-1. In C57BL/6J mice, which express a high-affinity Ah receptor that avidly binds TCDD, the ED50's of OPL for cleft palate and hydronephrosis were 0.44 and 0.11 g OPL kg-1 day-1, respectively. Maternal mortality was 5% at the highest dose. In DBA/2J fetuses, which express a low-affinity receptor, neither treatment-related cleft palate nor hydronephrosis was induced by dose levels that caused 36% maternal mortality. In hybrid D2B6F1 fetuses, the incidence of cleft palate reached only 8% at 2 g OPL kg-1 day-1 but the ED50 for hydronephrosis was 0.76 g OPL kg-1 day-1. TCDD was similarly administered to pregnant C57BL/6J mice at 0, 0.5, 1, 2, and 4 micrograms kg-1 day-1 and to DBA/2J mice at 0, 0.5, 2, 4, and 8 micrograms kg-1 day-1. In C57BL/6J fetuses, the ED50's for cleft palate and hydronephrosis were 4.6 and 0.73 microgram TCDD kg-1 day-1, respectively. In DBA/2J fetuses the ED50's for cleft palate and hydronephrosis were 15.0 and 6.4 micrograms TCDD kg-1 day-1, respectively. Both the OPL and TCDD caused maternal hepatomegaly and thymic atrophy in all strains, but increased only C57BL/6J fetal weights. OPL decreased the number of fetuses per C57BL/6J dam at the two highest doses but there were no other reproductive effects in any of the groups. It was concluded that the OPL is teratogenic and that hydronephrosis is a sensitive measure of TCDD toxicity in a

  20. Toxicity and bioaccumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by Chironomus tentans and Lumbriculus variegatus

    SciTech Connect

    West, C.W.; Ankley, G.T.; Elonen, G.E.; Phipps, G.W.; Fernandez, J.D.; Libal, J.J.; Nessa, D.

    1994-12-31

    Invertebrate exposure to 2,3,7,8-TCDD is important, not necessarily because of their sensitivity (which appears to be less than that of fish) , but as a vector from chemical reservoirs in sediments, through the food chain, to sensitive species. Chironomus tentans and Lumbriculus variegatus are not only vectors for TCDD to fish species, but C. tentans may also be a direct vector to avian species which feed upon emergent insects. For this reason determination of the kinetics of TCDD uptake by invertebrates is important, especially for those with short life spans such as midges, or those that reproduce as rapidly as oligochaetes. In these experiments, these two species were fed contaminated food at three different TCDD levels spanning three orders of magnitude. Tissue residue levels were measured over a time period which included several different life stages and points in the reproductive cycle of the two species and uptake and deputation rates determined. As expected, no significant impacts of TCDD on growth, reproduction or biomass of the invertebrates were observed. From this information predictions can be made on bioaccumulation of TCDD from differing levels of contamination, and potential food chain transfer of the compound to more sensitive species.

  1. Agent Orange Exposure and 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) in Human Milk.

    PubMed

    Scialli, Anthony R; Watkins, Deborah K; Ginevan, Michael E

    2015-06-01

    Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational exposure can be a mode of transgenerational effects of TCDD from Agent Orange. A review of the world's literature on milk concentrations of polychlorinated compounds showed the presence of TCDD and other dioxins and furans in all countries that have been assessed. The congener profile of these chemicals, that is, the proportion of different congeners in the sample, can be used to assess the source of milk contamination. Measurements in most countries, including contemporary measurements in Vietnam, are consistent with non-Agent Orange exposure sources, including industrial activities and incineration of waste. Models and supporting human data suggest that TCDD from breastfeeding does not persist in a child past adolescence and that the adult body burden of TCDD is independent of whether the individual was breast- or bottle-fed as a child. These findings suggest that exposure to Agent Orange in Vietnam did not result in persistent transgenerational exposure through human milk.

  2. Embryo toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to the wood duck (Aix sponsa)

    USGS Publications Warehouse

    Augspurger, T.P.; Tillitt, D.E.; Bursian, S.J.; Fitzgerald, S.D.; Hinton, D.E.; Di Giulio, R.T.

    2008-01-01

    We examined the sensitivity of the wood duck (Aix sponsa) embryo to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injecting the toxicant into their eggs. Six groups of wood duck eggs (n = 35 to 211 per trial) were injected with 0 to 4600 pg TCDD/g egg between 2003 and 2005. Injections were made into yolk prior to incubation, and eggs were subsequently incubated and assessed weekly for mortality. Significant TCDD-induced mortality was not observed through day 25 (90% of incubation). Liver, heart, eye, and brain histology were generally unremarkable. Hepatic ethoxyresorufin-O-deethylase activity, a biomarker of dioxin-like compound exposure, was induced by 12-fold in the 4600 pg/g treatment relative to controls. The median lethal dose for chicken (Gallus domesticus) eggs we dosed identically to wood duck eggs was about 100 pg/g, similar to other assessments of chickens. Among dioxin-like compound embryo lethality data for 15 avian genera, the wood duck 4600 pg/g no-observed-effect level ranks near the middle. Because no higher doses were tested, wood ducks may be like other waterfowl (order Anseriformes), which are comparatively tolerant to embryo mortality from polychlorinated dibenzo-p-dioxins and dibenzofurans when exposed by egg injection. ?? 2008 US Government.

  3. 2,3,7,8-TCDD effects on visual structure and function in swim-up rainbow trout

    USGS Publications Warehouse

    Carvalho, Paulo S. M.

    2004-01-01

    An understanding of mechanisms of contaminant effects across levels of biological organization is essential in ecotoxicology if we are to generate predictive models for population-level effects. We applied a suite of biochemical, histological, and behavioral end points related to visual structure and function and foraging behavior to evaluate effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) on swim-up rainbow trout. We detected a dose-dependent decrease in densities of retinal ganglion cells (RGC), key retinal neurons that link the eye with the brain. These changes resulted in corresponding deficits in visual/motor function including reductions in visual acuity and in scotopic and photopic thresholds due to TCDD. The loss of RGCs suggests an increase in convergence of synapses from photoreceptors to RGCs as a cellular mechanism for the visual deficits. Dose-dependent increases in immunohistochemical detection of CYP1A protein in the vasculature of the brain and eye choroid was proportional with decreased ganglion cell densities in the retina. TCDD-induced AHR-regulated effects on these tissues might be involved in the detected decrease in ganglion cell densities. Prey capture rate decreased after TCDD exposure only at the highest treatment groups evaluated. Collectively, these results show that TCDD causes biochemical and structural changes in the eye and brain of rainbow trout that are associated with behavioral deficits leading to decreased individual fitness.

  4. Embryonic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin impairs prey capture by zebrafish larvae.

    PubMed

    Chollett, Danielle; Perez, Kathryn E; King-Heiden, Tisha C

    2014-04-01

    As a ubiquitous, persistent environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has the potential to cause lethal deformities in larval fishes. Few studies have examined its impacts on larval growth and craniofacial development in conjunction with feeding capability. The authors used morphological and behavioral assessments to demonstrate that feeding capability of larvae is impaired even when craniofacial structures are not grossly malformed. Zebrafish embryos were exposed to 25 pg TCDD/mL, 50 pg TCDD/mL, or 100 pg TCDD/mL or <0.1% dimethyl sulfoxide for 1 h at 4 h postfertilization and then raised in clean water for 21 d or 90 d to assess craniofacial morphology, feeding capability, and long-term survival. The lower jaw was 5% smaller in 21-d larvae exposed to ≥ 50 pg TCDD/mL, and those larvae caught 10% fewer prey items; survival was reduced by 13% to 23%. The direct cause of TCDD's impacts on feeding capability is not known, but feeding success was correlated with growth, length of lower jaw, and survival. Since low larval mortality rates are key for recruitment, this suggests that exposure to concentrations of TCDD during embryonic development that do not initially cause mortality still has the potential to impact the recruitment success of feral fish. Furthermore, the present work provides additional evidence that behavioral end points are often more sensitive than morphological ones and should be included when assessing the sublethal toxicity of environmental contaminants.

  5. Agent Orange Exposure and 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) in Human Milk.

    PubMed

    Scialli, Anthony R; Watkins, Deborah K; Ginevan, Michael E

    2015-06-01

    Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational exposure can be a mode of transgenerational effects of TCDD from Agent Orange. A review of the world's literature on milk concentrations of polychlorinated compounds showed the presence of TCDD and other dioxins and furans in all countries that have been assessed. The congener profile of these chemicals, that is, the proportion of different congeners in the sample, can be used to assess the source of milk contamination. Measurements in most countries, including contemporary measurements in Vietnam, are consistent with non-Agent Orange exposure sources, including industrial activities and incineration of waste. Models and supporting human data suggest that TCDD from breastfeeding does not persist in a child past adolescence and that the adult body burden of TCDD is independent of whether the individual was breast- or bottle-fed as a child. These findings suggest that exposure to Agent Orange in Vietnam did not result in persistent transgenerational exposure through human milk. PMID:26195119

  6. Serum 2,3,7,8-tetrachlorodibenzo-p-dioxin levels in US Army Vietnam-era veterans

    SciTech Connect

    Not Available

    1988-09-02

    This study investigates whether military records can be used to identify US Army Vietnam veterans who were likely to be exposed to the herbicide Agent Orange. Serum levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a toxic contaminant in Agent Orange, were obtained for 646 ground combat troops who served in heavily sprayed areas of Vietnam and for 97 veterans who did not serve in Vietnam. The distributions of current TCDD levels in Vietnam and non-Vietnam veterans were nearly identical (mean in each group, approx. = 4 parts per trillion (ppt)). Only two men (both Vietnam veterans) had clearly elevated levels (> 20 ppt). Levels of TCDD did not tend to increase with greater likelihood of exposure to Agent Orange, as estimated from either military records of self-reported exposure. This study is consistent with other studies and suggests that most US Army ground troops who served in Vietnam were not heavily exposed to TCDD, except perhaps men whose jobs involved handling herbicides.

  7. Suppression of humoral immune responses by 2,3,7,8-tetrachlorodibenzo-p-dioxin intercalated in smectite clay.

    PubMed

    Boyd, Stephen A; Johnston, Cliff T; Pinnavaia, Thomas J; Kaminski, Norbert E; Teppen, Brian J; Li, Hui; Khan, Bushra; Crawford, Robert B; Kovalova, Natalia; Kim, Seong-Su; Shao, Hua; Gu, Cheng; Kaplan, Barbara L F

    2011-12-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic environmental contaminant found in soils and sediments. Because of its exceptionally low water solubility, this compound exists predominantly in the sorbed state in natural environments. Clay minerals, especially expandable smectite clays, are one of the major component geosorbents in soils and sediments that can function as an effective adsorbent for environmental dioxins, including TCDD. In this study, TCDD was intercalated in the smectite clay saponite by an incipient wetness method. The primary goal of this study was to intercalate TCDD in natural K-saponite clay and evaluate its immunotoxic effects in vivo. The relative bioavailability of TCDD was evaluated by comparing the metabolic activity of TCDD administered in the adsorbed state as an intercalate in saponite and freely dissolved in corn oil. This comparison revealed nearly identical TCDD-induced suppression of humoral immunity, a well-established and sensitive sequela, in a mammalian (mouse) model. This result suggests that TCDD adsorbed by clays is likely to be available for biouptake and biodistribution in mammals, consistent with previous observations of TCDD in livestock exposed to dioxin-contaminated ball clays that were used as feed additives. Adsorption of TCDD by clay minerals does not appear to mitigate risk associated with TCDD exposure substantially.

  8. 2,3,7,8-Tetrachlorodibenzo-p-dioxin exposure prevents cardiac valve formation in developing zebrafish.

    PubMed

    Mehta, Vatsal; Peterson, Richard E; Heideman, Warren

    2008-08-01

    Cardiovascular malformations are one of the most common congenital birth defects observed in humans. Defects in cardiac valves disrupt normal blood flow. Zebrafish are an outstanding experimental model for studying the effects that environmental contaminants have on developmental processes. Previous research has shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes blood regurgitation in the heart and reduces peripheral blood flow in embryonic zebrafish, suggesting some form of valve failure. To test this we used video microscopy to examine valve function and structure in developing zebrafish exposed to TCDD. TCDD exposure produced blood regurgitation at both the atrioventricular (AV) and bulboventricular (BV) junctions. In marked contrast to control embryos exposed to the vehicle dimethyl sulfoxide, embryos exposed to TCDD failed to form valve leaflets as the heart matured. In addition, whereas TCDD did not block initial formation of the bulbus arteriosus, we found that TCDD exposure prevented the normal growth and development of this portion of the outflow tract. TCDD altered the localization of endothelial cells at the AV and BV junctions and altered the localized expression of mRNAs bmp4 and notch1b normally associated with the nascent valves. Taken together, our results demonstrate that although TCDD does not prevent the initial specification of the presumptive valve locations, TCDD exposure produces severe alterations in valve development, leading to blood regurgitation and failing circulation in the developing zebrafish.

  9. Reproductive outcomes of mothers with potential exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Stockbauer, J.W.; Hoffman, R.E.; Schramm, W.F.; Edmonds, L.D.

    1988-08-01

    Animal laboratory studies have demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has fetotoxic and teratogenic effects at low doses. TCDD contamination of soil in nine residential areas of eastern Missouri began in 1971 when several horse arenas and dirt roads were sprayed for dust control with a mixture that contained waste oil and dioxin. The authors conducted an epidemiologic investigation to determine if adverse human reproductive outcomes are associated with exposure to soil contaminated with dioxin. The authors attempted to identify all births during the period of January 1, 1972 through December 31, 1982 that had potential exposure to dioxin, based on proximity of the maternal address to a location of known TCDD contamination. This group totaled 410 births. A matched set of 820 unexposed births was selected as a comparison group after being matched for maternal age and race, year of birth, hospital of birth, and plurality. The exposed group had increased risk ratios for infant, fetal, and perinatal death; low birth weight; and several subcategories of birth defects. None of these increased risk ratios for the exposed group were statistically significant. These results do not provide evidence that TCDD exposure has a substantial impact on the reproductive outcomes investigated. If TCDD does produce effects on reproductive health, a larger study and/or better measures of exposure may be needed to discover them.

  10. Trends in 2,3,7,8-TCDD concentrations in fish tissues downstream of pulp mills bleaching with chlorine

    SciTech Connect

    Abbott, J.D.; Hinton, S.W.

    1996-07-01

    Field measurements of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) concentrations in fish tissues from riverine environments impacted by treated pulp and paper industry effluent in the US were analyzed. Data from 39 sites in 14 states across the four major US paper-making regions were assembled and analyzed to determine the annual change in lipid-normalized concentrations of TCDD in fish tissue. The results provide strong evidence of a nationwide trend of decreasing lipid-normalized TCDD concentrations in fish tissue, with 84% of the examined sites showing a decrease. While the paucity of data currently limits any conclusions regarding the statistical significance at individual sites, the overall median rate calculated indicates a 0.36 annual fractional decrease in lipid-normalized concentrations of TCDD in fish tissue (0.18 to 0.51, 95% confidence interval); the average annual fractional decrease was 0.35 (0.23 to 0.47, 95% confidence interval). Subdividing fish into benthic and nonbenthic categories resulted in rates which were not significantly different from one another for both the median and mean statistics.

  11. Aromatic hydrocarbon responsiveness-receptor agonists generated from indole-3-carbinol in vitro and in vivo: Comparisons with 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Bjeldanes, L.F.; Jinyoung Kim; Grose, K.R.; Bartholomew, J.C. ); Bradfield, C.A. )

    1991-11-01

    Indole-3-carbinol (I3C) is a secondary plant metabolite produced in vegetables of the Brassica genus, including cabbage, cauliflower, and brussels sprouts. I3C is both an anti-initiator and a promoter of carcinogenesis. Consumption of I3C by humans and rodents can lead to marked increases in activities of cytochrome P-450-dependent monooxygenases and in a variety of phase II drug-metabolizing enzymes. The authors have reported previously that the enzyme-inducing activity of I3C is mediated through a mechanism requiring exposure of the compound to the low-pH environment of the stomach. They report here the aromatic hydrocarbon responsiveness-receptor K{sub d} values (22 nM-90 nM), determined with C57BL/6J mouse liver cytosol and the in vitro- and in vivo-molar yields of the major acid condensation products of I3C. They also show that indolo (3,2-b)carbazole (ICZ) is produced form I3C in yields on the order of 0.01% in vitro and, after oral intubation, in vivo. ICZ has a K{sub d} of 190 pM for aromatic hydrocarbon responsiveness-receptor binding and an EC{sub 50} of 269 nM for induction of cytochrome P4501A1, as measured by ethoxyresorufin O-deethylase activity in murine hepatoma Hepa 1c1c7 cells. The binding affinity of ICZ is only a factor of 3.7 {times} 10{sup {minus}2} lower than that of the highly toxic environmental contaminant and cancer promoter 2,3,7,8-tetrachlorodibenzo-p-dioxin. ICZ and related condensation products appear responsible for the enzyme-inducing effects of dietary I3C.

  12. Long-term fate and bioavailability of sediment associated 2,3,7,8-tetrachlorodibenzofuran in littoral enclosures

    SciTech Connect

    Currie, R.S.; Fairchild, W.L.; Holoka, M.H.; Muir, D.C.G.

    2000-06-01

    the fate and bioavailability of 2,3,7,8-tetrachlorodibenzofuran (TCDF; 4,6-tritium labeled) was examined over a 3-year period in littoral enclosures in a small oligotrophic lake in the Experimental Lakes Area. Tetrachlorodibenzofuran was added as a single dose or as five small multiple additions over a 5-d period in a sediment slurry. Tetrachlorodibenzofuran was rapidly redistributed, mainly to bottom sediments reflecting removal on settling particles. Between 0 and 120 d. 80 to 90% of TCDF in the water column was associated with particles (>1 {micro}m). The highest concentration of TCDF in suspended particles was consistently observed in the smallest size fraction (0.22--1 {micro}m) at 326 to 464 d post treatment. Mode of addition had no effect on TCDF concentrations in water or surficial sediments or pore waters throughout the experiment. Mean TCDF concentrations in surficial sediment were 1.830 {+-} 1.180 pg/g whereas they averaged 1.260 {+-} 596 pg/g OC from 318 to 851 d post treatment. Increasing concentrations of TCDE in lower sediment layers at 952 d suggests that TCDF was either diffusing into the sediment or undergoing burial. Fugacity (f) calculations indicated that the TCDF in enclosures shifted from disequilibrium favoring the water column to a disequilibrium with respect to bottom sediments from day 21 onward. Initially, TCDF was more bioavailable to filtering and deposit feeders (mussels, Chironomidae, Hexagenia sp., and zooplankton) in enclosures receiving multiple additions; however, differences were rarely statistically significant. Concentrations of TCDF in all organisms were initially high, and they decreased in later sampling periods. Biota--sediment-accumulation factors (BSAFs) in mussels and crayfish were >1 in the early sampling periods, which reflected greater bioavailability of the added particle-borne TCDF. By 851 d, BSAFs had declined to 0.02 to 0.04, reflecting removal of TCDF from the water column and from surficial sediments.

  13. Potentiation and antagonism of 2,3,7,8-tetrachlorodibenzo-p-dioxin effects in a complex environmental mixture.

    PubMed

    Silkworth, J B; Cutler, D S; O'Keefe, P W; Lipinskas, T

    1993-04-01

    There is increasing need to understand the toxicity of complex environmental mixtures. The organic phase of a leachate (OPL) from the Love Canal chemical dump site is a complex mixture that contains over 100 organic compounds, including 0.74 ppm 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Mice congenic at the Ah locus were used to evaluate several toxic effects of the OPL, including immune function and hepatic enzyme induction. OPL toxicity was compared with that of pure TCDD in both C57BL/6J Ahb/b and congenic C57BL/6 Ahd/d (B6.D2) mice. Mice were given single oral doses of up to 2 g OPL/kg or 100 micrograms TCDD/kg, immunized, and evaluated after 7 days. The TCDD equivalent of the OPL was determined to be 3.9 and 5.0 ppm in C57BL/6J and B6.D2 mice, respectively. This is six times the TCDD content. The Ah phenotype-dependent response ratio was calculated by dividing the dose required to cause an effect in the B6.D2 strain by the dose causing the same effect in the C57BL/6J strain. Ratios based on both ED50s and the lowest observed adverse effect levels were used to determine whether each adverse effect was Ah phenotype-dependent, the extent to which TCDD contributed to the effect, whether there were interactive effects between the AhR ligands and nonligands and if they were additive, antagonistic, or synergistic, and whether the response was predictable based on the known chemical composition of the mixture. It was concluded that the non-TCDD component potentiated TCDD immune suppression, and possibly thymic atrophy, through AhR mechanisms. In contrast, this analysis indicated that the non-TCDD component of the OPL antagonized the ability of the TCDD component to induce hepatic AHH activity whereas OPL hepatomegaly was caused primarily by the non-TCDD component of the OPL. This study demonstrates that the toxicity of mixtures containing TCDD may not be accurately predicted based on the TCDD content alone and that this approach could be useful in the toxicologic

  14. CD8+CD45RA+CCR7+FOXP3+ T cells with immunosuppressive properties: a novel subset of inducible human regulatory T cells

    PubMed Central

    Suzuki, Masakatsu; Jagger, Ann L.; Konya, Christine; Shimojima, Yasuhiro; Pryshchep, Sergey; Goronzy, Jörg J.; Weyand, Cornelia M.

    2012-01-01

    CD8 T cells stimulated with a suboptimal dose of anti-CD3 antibodies (100 pg/ml) in the presence of IL-15 retain a naïve phenotype with expression of CD45RA, CD28, CD27 and CCR7 but acquire new functions and differentiate into immunosuppressive T cells. CD8+CCR7+ Tregs express FOXP3 and prevent CD4 T cells from responding to T-cell receptor stimulation and entering the cell cycle. Naïve CD4 T cells are more susceptible to inhibition than memory cells. The suppressive activity of CD8+CCR7+ Tregs is not mediated by IL-10, TGF-β, CTLA-4, CCL4 or adenosine and relies on interference with very early steps of the TCR signaling cascade. Specifically, CD8+CCR7+ Tregs prevent TCR-induced phosphorylation of ZAP70 and dampen the rise of intracellular calcium in CD4 T cells. The inducibility of CD8+CCR7+ Tregs is correlated to the age of the individual with peripheral blood lymphocytes of donors older than 60 years yielding low numbers of FOXP3low CD8 Treg cells. Loss of CD8+CCR7+ Tregs in the elderly host may be of relevance in the aging immune system as immunosenescence is associated with a state of chronic smoldering inflammation. PMID:22821963

  15. Arsenic inhibits induction of cytochrome P450 1A1 by 2,3,7,8-tetrachlorodibenzo-p-dioxin in human hepatoma cells.

    PubMed

    Chao, How-Ran; Tsou, Tsui-Chun; Li, Lih-Ann; Tsai, Feng-Yuan; Wang, Ya-Fen; Tsai, Cheng-Hsien; Chang, Eddy Essen; Miao, Zhi-Feng; Wu, Chia-Hsin; Lee, Wen-Jhy

    2006-09-21

    The aim of this study was to examine the arsenic effect on activation of aryl hydrocarbon receptor (AhR)-mediated gene expression by 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in human hepatoma cells. The human hepatoma Huh7 cells were treated with sodium arsenite (NaAsO2) from 0.5 to 20 microM for 24 h. Our data revealed that NaAsO2 < or = 10 microM caused no significant cytotoxic effect on Huh7 cells (p>0.05). We also established a dioxin-responsive element (DRE)-mediated Chemical Activated LUciferase eXpression (CALUX) cell line, Huh7-DRE-Luc, by stable transfection of Huh7 with a DRE-driven firefly luciferase reporter plasmid (4xDRE-TATA-Luc). Treatments of Huh7-DRE-Luc and Huh7 with NaAsO2 attenuated the 2,3,7,8-TCDD-induced DRE-CALUX and cytochrome P450 1A1 (CYP1A1) activations, respectively, in a dose-dependent manner. We found that the calculated CALUX-toxic equivalent (TEQ) levels induced by cotreatment of NaAsO2 > or = 3.0 microM and 10 nM 2,3,7,8-TCDD were significantly lower than that induced by 2,3,7,8-TCDD alone (p<0.05). In the present study, we demonstrated that arsenic not only inhibited the TCDD-induced CYP1A1 activation but also interfered with DRE-CALUX bioassay in human hepatoma cells. Our finding also suggests that extensive cleanup of sample for removal of any possible interfering factor is critical to guarantee the accuracy of dioxin-TEQ levels using DRE-CALUX bioassay. PMID:16713074

  16. Embryotoxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in the ring-necked pheasant

    SciTech Connect

    Nosek, J.A.; Craven, S.R. . Dept. of Wildlife Ecology); Sullivan, J.R. . Wisconsin Dept. of Natural Resources); Gendron-Fitzpatrick, A. . Research Animal Veterinarian and Research Animal Resource Committee); Peterson, R.E. . School of Pharmacy and Environmental Toxicology Center)

    1993-07-01

    Fertilized eggs of ring-necked pheasants (Phasianus colchicus) were injected into the albumin or yolk with vehicle or graded doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on day 0 of embryonic development and toxicity was assessed in 1-d-old hatchlings and 28-d-old chicks. The most sensitive effect of in ovo TCDD exposure was induction of hepatic ethoxyresorufin-O-deethylase (EROD) activity in 1-d-old hatchlings. The ED50 for this response was 312 pg TCDD/g egg. Embryo mortality was the most sensitive sign of toxicity. The TCDD dose that caused 50% mortality above control (LD50) when injected into the egg albumin or yolk was 1,354 and 2,182 pg TCDD/g egg, respectively. At egg TCDD doses up to and including 1,000 pg TCDD/g egg, no effect was detected in 1-d-old hatchlings and 28-d-old chicks in body growth, organ weights, carcass morphometrices, incidence of edema, or incidence of histological alterations in the liver, spleen, heart, Bursa of Fabricius, or thymus. Egg TCDD doses as high as 1,000 pg TCDD/g egg also had no effect on cardiac morphometrices or incidence of cardiac malformations in 1-d-old hatchlings, or on antibody-mediated immunity in 28-d-old chicks. The authors conclude that embryo mortality is the most sensitive sign of TCDD toxicity in the ring-necked pheasant following in ovo exposure.

  17. Synergistic effects of tributyltin and 2,3,7,8-tetrachlorodibenzo-p-dioxin on differentiating osteoblasts and osteoclasts

    SciTech Connect

    Koskela, Antti; Viluksela, Matti; Keinänen, Meeri; Tuukkanen, Juha; Korkalainen, Merja

    2012-09-01

    The purpose of this study was to examine the effects of the persistent and accumulative environmental pollutants tributyltin (TBT) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) individually and in combination on differentiating bone cells. TBT and TCDD are chemically distinct compounds with different mechanisms of toxicity, but they typically have the same sources of exposure and both have been shown to affect bone development at low exposure levels. Bone marrow stem cells were isolated from femurs and tibias of C57BL/6 J mice, differentiated in culture into osteoblasts or osteoclasts and exposed to 0.1–10 nM TBT, 0.01–1 nM TCDD or 10 nM TBT + 1 nM TCDD. In osteoblasts, the combined exposure to TBT and TCDD significantly decreased the mRNA expression of alkaline phosphatase and osteocalcin more than TBT or TCDD alone. PCR array showed different gene expression profiles for TBT and TCDD individually, and the combination evoked several additional alterations in gene expression. Expression of aryl hydrocarbon receptor repressor (AHRR) was increased by TCDD as expected, but simultaneous exposure to TBT prevented the increase thus potentially strengthening AHR-mediated effects of TCDD. The number of osteoclasts was reduced by TCDD alone and in combination with TBT, but TBT alone had no effect. However, the total area of resorbed bone was remarkably lower after combined exposure than after TBT or TCDD alone. In conclusion, very low concentrations of TBT and TCDD have synergistic deleterious effects on bone formation and additive effects on bone resorption. -- Highlights: ► Combined exposure to TCDD and TBT evoked a unique gene expression profile. ► Osteoblast differentiation was synergistically disturbed after combined exposure. ► Bone resorbing activity was additively decreased after combined exposure.

  18. Inter-strain heterogeneity in rat hepatic transcriptomic responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

    SciTech Connect

    Yao, Cindy Q.; Prokopec, Stephenie D.; Watson, John D.; Pang, Renee; P'ng, Christine; Chong, Lauren C.; Harding, Nicholas J.; Pohjanvirta, Raimo; Okey, Allan B.; Boutros, Paul C.

    2012-04-15

    The biochemical and toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) have been the subject of intense study for decades. It is now clear that essentially all TCDD-induced toxicities are mediated by DNA–protein interactions involving the Aryl Hydrocarbon Receptor (AHR). Nevertheless, it remains unknown which AHR target genes cause TCDD toxicities. Several groups, including our own, have developed rodent model systems to probe these questions. mRNA expression profiling of these model systems has revealed significant inter-species heterogeneity in rodent hepatic responses to TCDD. It has remained unclear if this variability also exists within a species, amongst rodent strains. To resolve this question, we profiled the hepatic transcriptomic response to TCDD of diverse rat strains (L-E, H/W, F344 and Wistar rats) and two lines derived from L-E × H/W crosses, at consistent age, sex, and dosing (100 μg/kg TCDD for 19 h). Using this uniquely consistent dataset, we show that the majority of TCDD-induced alterations in mRNA abundance are strain/line-specific: only 11 genes were affected by TCDD across all strains, including well-known dioxin-responsive genes such as Cyp1a1 and Nqo1. Our analysis identified two novel universally dioxin-responsive genes as well as 4 genes induced by TCDD in dioxin-sensitive rats only. These 6 genes are strong candidates to explain TCDD-related toxicities, so we validated them using 152 animals in time-course (0 to 384 h) and dose–response (0 to 3000 μg/kg) experiments. This study reveals that different rat strains exhibit dramatic transcriptional heterogeneity in their hepatic responses to TCDD and that inter-strain comparisons can help identify candidate toxicity-related genes.

  19. 2,3,7,8-Tetrachlorodibenzo-p-dioxin plasma levels in Seveso 20 years after the accident.

    PubMed

    Landi, M T; Consonni, D; Patterson, D G; Needham, L L; Lucier, G; Brambilla, P; Cazzaniga, M A; Mocarelli, P; Pesatori, A C; Bertazzi, P A; Caporaso, N E

    1998-05-01

    In 1976, near Seveso, Italy, an industrial accident caused the release of large quantities of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) into the atmosphere, resulting in the highest levels of the toxicant ever recorded in humans. The contaminated area was divided into three zones (A, B, R) corresponding to decreasing TCDD levels in soil, and cohort including all residents was enumerated. The population of the surrounding noncontaminated area (non-ABR) was chosen as referent population. Two decades after the accident. plasma TCDD levels were measured in 62 subjects randomly sampled from the highest exposed zones (A and B) and 59 subjects from non-ABR, frequency matched for age, gender, and cigarette smoking status. Subjects living in the exposed areas have persistently elevated plasma TCDD levels (range = 1.2-89.9 ppt; geometric mean = 53.2 and 11.0 ppt for Zone A and Zone B, respectively). Levels significantly decrease by distance from the accident site (p = 0.0001), down to general population values (4.9 ppt) in non-ABR, thus validating the original zone classification based on environmental measurements. Women have higher TCDD levels than men in the entire study area (p = 0.0003 in Zone B; p = 0.007 in non-ABR). This gender difference persists after adjustment for location within the zone, consumption of meat derived from locally raised animals, age, body mass index, and smoking. There is no evidence for a gender difference in exposure, so variation in metabolism or elimination due to body fat or hormone-related factors may explain this finding. Elevated TCDD levels in women may contribute to adverse reproductive, developmental, and cancer outcomes.

  20. Determination of ( sup 3 H)-2,3,7,8-tetrachlorodibenzo-p-dioxin in human feces to ascertain its relative metabolism in man

    SciTech Connect

    Wendling, J.M.; Orth, R.G.; Poiger, H. )

    1990-04-15

    Human feces samples from a self-dosing experiment were analyzed by gas chromatography/mass spectrometry (GC/MS) for ({sup 3}H)-2,3,7,8-tetrachlorodibenzo-p-dioxin ({sup 3}H-2378-TCDD) to determine that 36-44% of the radioactivity was attributable to the parent compound. This method, using isotope dilution analysis, proved to be difficult due to the unexpectedly higher native 2378-TCDD background which created abnormally large precision ranges around the calculated feces concentrations of 0.1-0.2 pg/g. These results were supported by additional analyses involving the GC/MS chemical cleanup method combined with liquid scintillation counting which showed that at most, 50% of the radioactivity was due to 2378-TCDD metabolites resulting in a minimum metabolism of 50% for these samples.

  1. Single-Step Synthesis of 5,6,7,8-Tetrahydroindolizines via Annulation of 2-Formylpiperidine and 1,3-Dicarbonyl Compounds.

    PubMed

    Capomolla, Simona S; Lim, Ngiap-Kie; Zhang, Haiming

    2015-07-17

    An expedient single-step synthesis of 5,6,7,8-tetrahydroindolizines has been achieved via the annulation of commercially available 2-formylpiperidine hydrochloride and 1,3-dicarbonyl compounds in THF in the presence of pyrrolidine and 4 Å molecular sieves. A variety of β-ketoesters, ketones, and amides participated in this annulation chemistry, affording the desired 5,6,7,8-tetrahydroindolizines in moderate to good yields.

  2. Eu3+/Sm3+ hybrids based with 8-hydroxybenz[de]anthracen-7-one organically modified mesoporous silica SBA-15/16

    NASA Astrophysics Data System (ADS)

    Gu, Yan-Jing; Yan, Bing

    2015-12-01

    A series of organic-inorganic hybrid materials were prepared by linking lanthanide (Eu3+, Sm3+) complexes to mesoporous SBA-15/SBA-16 through 8-hydroxybenz[de]anthracen-7-one modified silane (HBA-Si) as linker. The physical characterizations of these hybrids revealed that they all have high surface area, uniformity in mesostructure. The luminescence properties of these covalently bonded materials (denoted as Ln(HBA-SBA-15)3phen and Ln(HBA-SBA-16)3phen) were compared with ternary complexes (Ln(HBA)3phen) (Ln = Eu, Sm). Eu(HBA-SBA-15(16))3phen hybrids display better thermal stability, whose luminescent lifetimes and quantum efficiencies were matchable with those of Eu(HBA)3phen complex in spite of its much lower effective condensation of Eu3+ species. In addition, the luminescent performance of functionalized SBA-15 hybrids was more favorable than that of functionalized SBA-16 hybrids, revealing that SBA-15 was a better host material for lanthanide complex than mesoporous silica SBA-16.

  3. Optical Temperature Sensor Through Upconversion Emission from the Er3+ Doped SrBi8Ti7O27 Ferroelectrics

    NASA Astrophysics Data System (ADS)

    Zou, Hua; Wang, Xusheng; Hu, Yifeng; Zhu, Xiaoqing; Sui, Yongxing; Song, Zhitang

    2016-06-01

    Er doped SrBi8Ti7O27 (SBT) ferroelectric ceramics were prepared by a solid-state reaction technique. By Er doping, the intensive green upconversion emissions were recorded under 980 nm diode laser excitation with 20 mW. The fluorescence spectrum was investigated in the temperature range of 150-580 K. By the fluorescence intensity ratio technique, the green emission band was studied as a function of temperature with a maximum sensing sensitivity of 0.0028 at 510 K. These results indicate that the Er doped SBT ferroelectric ceramics are promising multifunctional sensing materials.

  4. A novel redox reaction between 8-Aza-5,7-dimethyl-2-trifluoromethylchromone and alkyl mercaptoacetates. Facile synthesis of CF3-containing 2-pyridone derivatives.

    PubMed

    Sosnovskikh, Vyacheslav Ya; Barabanov, Mikhail A; Usachev, Boris I

    2004-11-26

    8-Aza-5,7-dimethyl-2-trifluoromethylchromone reacts with alkyl mercaptoacetates in the presence of triethylamine to give pyrido derivatives of 2-oxa-7-thiabicyclo[3.2.1]octane, which undergo the reductive ring opening to alkyl 2-[[3-(4,6-dimethyl-2-oxo-1,2-dihydropyridin-3-yl)-3-oxo-1-(trifluoromethyl)propyl]sulfanyl]acetates. The latter can be also obtained directly from 8-aza-5,7-dimethyl-2-trifluoromethylchromone and behave as the masked alpha,beta-unsaturated ketone, 4,6-dimethyl-3-(4,4,4-trifluorobut-2-enoyl)pyridin-2(1H)-one. This compound was independently synthesized from 3-acetyl-4,6-dimethyl-2-pyridone, and its synthetic potential was studied. A wide variety of 2-pyridone derivatives containing the CF(3) group have been prepared in good to moderate yields.

  5. Coulomb Stress Change and Seismic Hazard of Rift Zones in Southern Tibet after the 2015 Mw7.8 Nepal Earthquake and Its Mw7.3 Aftershock

    NASA Astrophysics Data System (ADS)

    Dai, Z.; Zha, X.; Lu, Z.

    2015-12-01

    In southern Tibet (30~34N, 80~95E), many north-trending rifts, such as Yadong-Gulu and Lunggar rifts, are characterized by internally drained graben or half-graben basins bounded by active normal faults. Some developed rifts have become a portion of important transportation lines in Tibet, China. Since 1976, eighty-seven >Mw5.0 earthquakes have happened in the rift regions, and fifty-five events have normal faulting focal mechanisms according to the GCMT catalog. These rifts and normal faults are associated with both the EW-trending extension of the southern Tibet and the convergence between Indian and Tibet. The 2015 Mw7.8 Nepal great earthquake and its Mw7.3 aftershock occurred at the main Himalayan Thrust zone and caused tremendous damages in Kathmandu region. Those earthquakes will lead to significant viscoelastic deformation and stress changes in the southern Tibet in the future. To evaluate the seismic hazard in the active rift regions in southern Tibet, we modeled the slip distribution of the 2015 Nepal great earthquakes using the InSAR displacement field from the ALOS-2 satellite SAR data, and calculated the Coulomb failure stress (CFS) on these active normal faults in the rift zones. Because the estimated CFS depends on the geometrical parameters of receiver faults, it is necessary to get the accurate fault parameters in the rift zones. Some historical earthquakes have been studied using the field data, teleseismic data and InSAR observations, but results are in not agreement with each other. In this study, we revaluated the geometrical parameters of seismogenic faults occurred in the rift zones using some high-quality coseismic InSAR observations and teleseismic body-wave data. Finally, we will evaluate the seismic hazard in the rift zones according to the value of the estimated CFS and aftershock distribution.

  6. 2,3,7,8-TCDD enhances the sensitivity of mice to concanavalin A immune-mediated liver injury

    SciTech Connect

    Fullerton, Aaron M.; Roth, Robert A.; Ganey, Patricia E.

    2013-01-15

    Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injury resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► Fas

  7. Synthesis and resolution of (+-)-7-chloro-8-hydroxy-1-(3'-iodophenyl)-3-methyl-2,3,4,5-tetrahydro- 1H-3- benzazepine (TISCH): A high affinity and selective iodinated ligand for CNS D1 dopamine receptor

    SciTech Connect

    Chumpradit, S.; Kung, M.P.; Billings, J.J.; Kung, H.F. )

    1991-03-01

    The synthesis and resolution of (+-)-7-chloro-8-hydroxy-1-(3'-iodophenyl)-3-methyl-2,3,4,5-tetrahydro-1 H-3- benzazepine, (+/-)-TISCH (8) has been achieved by resolution of intermediate 4, the O-methoxyl, 3'-bromo derivative, as the diastereomeric camphor sulfonate salt. The final products, R-(+)-8 and S-(-)-8, were prepared by treatment of R-(+)- or S-(-)-7, the 3'-tributyltin intermediates, with iodine in chloroform, followed by O-demethylation. By using HPLC with a chiral column, the optical purity (greater than 99%) of the intermediates and the final compounds was determined. Radioiodination was achieved by an iodo-destannylation reaction with sodium (125I)iodide and hydrogen peroxide. As expected, the R-(+)-(125I)-8 (the active isomer) displayed high affinity and selectivity to the CNS D-1 receptor in rat striatum tissue preparation (Kd = 0.205 nM). The rank order of potency was as follows: SCH-23390 (1a) greater than (+/-)-8 greater than (+)-butaclamol greater than spiperone, WB4101 greater than dopamine, 5-HT. After an iv injection, the R-(+)-(125I)-8 penetrated the blood-brain barrier with ease and displayed specific regional distribution corresponding to the D-1 receptor density, while the S-(-)-(125I)-8 showed no specific uptake. The data suggest that the ligand may be useful as a pharmacological tool for characterizing the D-1 dopamine receptor. When labeled with I-123, this ligand is a potential agent for in vivo imaging of CNS D-1 dopamine receptor.

  8. Fluctuation induced magneto-conductivity of Y3Ba5Cu8O18±x and YBa2Cu3O7-d

    NASA Astrophysics Data System (ADS)

    Slimani, Y.; Hannachi, E.; Ben Salem, M. K.; Hamrita, A.; Ben Salem, M.; Ben Azzouz, F.

    2015-12-01

    A comparative study of the fluctuation magneto-conductivity in YBa2Cu3O7-d (noted Y-123) and Y3Ba5Cu8O18±x (noted Y-358) polycrystalline samples was carried out. Samples were synthesized in oxygen atmosphere using a standard solid state reaction technique. Phases and microstructure have been systematically investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The magneto-conductivity was measured in a magnetic field ranging from 0 T to 7 T applied perpendicular to the current path direction. The magneto-conductivity data were analyzed in terms of the temperature derivative of the resistivity and the logarithmic temperature derivative of the conductivity χσ = -d(ln Δσ) dT, where Δσ is the fluctuation conductivity. Analyses of the magneto-conductivity data reveal that Y-123 possesses a better quality of intrinsic Josephson junction compared to Y-358 one while in the former one the depression in superconducting temperature is more pronounced. The applied magnetic field narrowed substantially the three dimensions (3D) Gaussian regime and for Y-358 sample this regime is vanished for high magnetic field ( >1 T). Results are discussed in relation with the difference in the structure and microstructure Y-358 and Y-123. The upper critical and the irreversibility magnetic fields were estimated and were found to be higher in the Y-358 sample.

  9. 7 CFR 8.8 - Use by public informational services.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Use by public informational services. 8.8 Section 8.8 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.8 Use by public informational services. (a) In any advertisement, display, exhibit, visual and audio-visual material, news...

  10. 7 CFR 8.8 - Use by public informational services.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Use by public informational services. 8.8 Section 8.8 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.8 Use by public informational services. (a) In any advertisement, display, exhibit, visual and audio-visual material, news...

  11. Effects of chronic exposure to 2, 3, 7, 8,-tetrachlorodibenzo-p-dioxin on sister chromatid exchange levels in peripheral lymphocytes of the rhesus monkey

    SciTech Connect

    Lim, M.; Jacobson-Kram, D.; Bowman, R.E.; Williams, J.R.

    1987-01-01

    Frequencies of sister chromatid exchanges and chromosomal aberrations were examined in peripheral lymphocytes of Rhesus monkeys that had been fed a diet containing 25 parts per trillion 2,3,7,8-tetrachlorodibenzo-p-dioxin for a period of 4 years. When compared to non-exposed control animals, no significant differences were noted for either of these cytogenetic end points. In addition, there was not a significant difference in sister chromatid exchange response to a challenge dose of mitomycin C in cells from 2,3,7,8-tetrachlorodibenzo-p-dioxin exposed animals compared to controls. The results confirm the lack of genotoxic effects associated with 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure.

  12. Love Canal Emergency Declaration Area habitability study. Volume 4. Soil assessment: 2,3,7,8-TCDD (tetrachlorodibenzo-p-dioxin). Final report

    SciTech Connect

    Not Available

    1988-03-01

    Environmental studies were conducted to provide data that could be used by the Commissioner of Health for the State of New York in determining whether the Emergency Declaration Area (EDA) surrounding the Love Canal hazardous-waste site is habitable. A soil assessment for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was conducted to determine whether the soil in the EDA contains 2,3,7,8-TCDD at levels above the level of concern set by the Centers for Disease Control: 1.0 ppb. Samples of surface soil were collected at 2,274 locations throughout the EDA.

  13. Humanized Affinity-matured Monoclonal Antibody 8H9 Has Potent Antitumor Activity and Binds to FG Loop of Tumor Antigen B7-H3.

    PubMed

    Ahmed, Mahiuddin; Cheng, Ming; Zhao, Qi; Goldgur, Yehuda; Cheal, Sarah M; Guo, Hong-fen; Larson, Steven M; Cheung, Nai-kong V

    2015-12-11

    B7-H3 (CD276) is both an inhibitory ligand for natural killer cells and T cells and a tumor antigen that is widely expressed among human solid tumors. Anti-B7-H3 mouse monoclonal antibody 8H9 has been successfully used for radioimmunotherapy for patients with B7-H3(+) tumors. We present the humanization, affinity maturation, and epitope mapping of 8H9 based on structure determination, modeling, and yeast display methods. The crystal structure of ch8H9 Fab fragment was solved to 2.5-Å resolution and used as a template for humanization. By displaying the humanized 8H9 single chain Fv (scFv) on the surface of yeast, the affinity was matured by sequential random mutagenesis and fluorescence-activated cell sorting. Six mutations (three in the complementarity-determining region and three in the framework regions) were identified and incorporated into an affinity-matured humanized 8H9 construct (hu8H9-6m) and an affinity-matured chimeric 8H9 construct (ch8H9-6m). The hu8H9-6m scFv had a 160-fold improvement in affinity (0.9 nm KD) compared with parental hu8H9 scFv (144 nm KD). The IgG formats of ch8H9-6m and hu8H9-6m (nanomolar to subnanomolar KD) had 2-9-fold enhancements in affinity compared with their parental forms, potent in vitro antibody-dependent cell-mediated cytotoxicity (0.1-0.3 μg/ml EC50), and high tumor uptake in mouse xenografts. Based on in silico docking studies and experimental validation, the molecular epitope of 8H9 was determined to be dependent on the FG loop of B7-H3, a region critical to its function in immunologic blockade and unique among anti-B7-H3 antibodies published to date. PMID:26487718

  14. X-ray Mapping in Heterocyclic Design: XIV. Tricyclic Heterocycles Based on 2-Oxo-1,2,5,6,7,8-Hexahydroquinoline-3-Carbonitrile

    SciTech Connect

    Mazina, O.S.; Rybakov, V.B.; Chernyshev, V.V.; Babaev, E.V.; Aslanov, L.A.

    2004-11-01

    The structures of four compounds are studied using single-crystal X-ray diffraction: 1-[2-(4-chlorophenyl)-2-oxoethyl]-2-oxo-1,2,5,6,7,8-hexahydroquinoline -3-carbonitrile [a = 4.908(4) A, b = 11.644(10) A, c = 13.587(2) A, {beta} = 94.31(5) deg., Z = 2, space group P2{sub 1}]; 2-[2-(4-chlorophenyl)-2-oxoethoxy]-5,6,7,8-tetrahydroquinoline -3-carbonitrile [a = 7.6142(8) A, b = 14.778(2) A, c = 14.132(2) A, {beta} = 100.38(1) deg., Z = 4, space group P2{sub 1}/c]; 4-(aminocarbonyl)-2-(chlorophenyl)-6,7,8,9-tetrahydro[1.3]oxazolo[3,2-a] quinolin-3-ium perchlorate [a = 5.589(7) A, b = 24.724(15) A, c = 13.727(5) A, {beta} = 97.66(9) deg., Z = 4, space group P2{sub 1}/n]; and (3-amino-5,6,7,8-tetrahydrofuro[2,3-b]quinolin-2-yl)-(4-chlorophenyl) methanone [a = 7.150(2) A, b = 7.4288(10) A, c = 15.314(3) A, {alpha} = 98.030(10) deg., {beta} = 99.21(2) deg., {gamma} = 105.34(2) deg., Z = 2, space group P1-bar]. The structures are solved by direct methods and refined by the full-matrix least-squares procedure in the anisotropic approximation to R = 0.0728, 0.0439, 0.1228, and 0.0541, respectively. The structure of 1-(4-chlorophenyl)-4-piperidin-1-yl-8,9-dihydro-7H-pyrrolo[3.2.1-ij] quinoline-5-carboxamide [a = 23.9895(9) A, b = 5.1557(3) A, c = 17.0959(9) A, {beta} = 106.43 deg., Z = 4, space group P{sub 1}/c] is investigated by X-ray powder diffraction. This structure is solved using the grid search procedure and refined by the Rietveld method to R{sub wp} = 0.0773, R{sub exp} = 0.0540, R{sub p} = 0.0585, R{sub b} = 0.1107, and {chi}{sup 2} = 1.78.

  15. 2,3,7,8-Tetrachlorodibenzo-p-dioxin in breast milk increases autistic traits of 3-year-old children in Vietnam.

    PubMed

    Nishijo, M; Pham, T T; Nguyen, A T N; Tran, N N; Nakagawa, H; Hoang, L V; Tran, A H; Morikawa, Y; Ho, M D; Kido, T; Nguyen, M N; Nguyen, H M; Nishijo, H

    2014-11-01

    Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (⩾3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)--the toxic equivalents (TEQ) levels⩾17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).

  16. Environmentally relevant concentrations of arsenite and monomethylarsonous acid inhibit IL-7/STAT5 cytokine signaling pathways in mouse CD3+CD4-CD8- double negative thymus cells.

    PubMed

    Xu, Huan; Lauer, Fredine T; Liu, Ke Jian; Hudson, Laurie G; Burchiel, Scott W

    2016-04-15

    Environmental arsenic exposure is a public health issue. Immunotoxicity induced by arsenic has been reported in humans and animal models. The purpose of this study was to evaluate mechanisms of As(+3) and MMA(+3) toxicity in mouse thymus cells. Because we know that MMA(+3) inhibits IL-7 signaling in mouse bone marrow pre-B cells, we studied the influence of As(+3) and MMA(+3) on T cell development in the thymus at the earliest stage of T cell development (CD4-CD8-, double negative, DN) which requires IL-7 dependent signaling. We found in a DN thymus cell line (D1) that a low concentration of MMA(+3) (50 nM) suppressed IL-7 dependent JAK1, 3 and STAT5 signaling. As(+3) suppressed STAT5 and JAK3 at higher concentrations (500 nM). Cell surface expression of the IL-7 receptor (CD127) was also suppressed by 50 nM MMA(+)3, but was increased by 500 NM As(+3), indicating possible differences in the mechanisms of action of these agents. A decrease in cyclin D1 protein expression was observed in D1 cells exposed to As(+3) at 500 nM and MMA(+3) starting at 50 nM, suggesting that arsenic at these environmentally-relevant doses suppresses early T cell development through the inhibition of IL-7 signaling pathway. PMID:26921788

  17. Environmentally relevant concentrations of arsenite and monomethylarsonous acid inhibit IL-7/STAT5 cytokine signaling pathways in mouse CD3+CD4-CD8- double negative thymus cells.

    PubMed

    Xu, Huan; Lauer, Fredine T; Liu, Ke Jian; Hudson, Laurie G; Burchiel, Scott W

    2016-04-15

    Environmental arsenic exposure is a public health issue. Immunotoxicity induced by arsenic has been reported in humans and animal models. The purpose of this study was to evaluate mechanisms of As(+3) and MMA(+3) toxicity in mouse thymus cells. Because we know that MMA(+3) inhibits IL-7 signaling in mouse bone marrow pre-B cells, we studied the influence of As(+3) and MMA(+3) on T cell development in the thymus at the earliest stage of T cell development (CD4-CD8-, double negative, DN) which requires IL-7 dependent signaling. We found in a DN thymus cell line (D1) that a low concentration of MMA(+3) (50 nM) suppressed IL-7 dependent JAK1, 3 and STAT5 signaling. As(+3) suppressed STAT5 and JAK3 at higher concentrations (500 nM). Cell surface expression of the IL-7 receptor (CD127) was also suppressed by 50 nM MMA(+)3, but was increased by 500 NM As(+3), indicating possible differences in the mechanisms of action of these agents. A decrease in cyclin D1 protein expression was observed in D1 cells exposed to As(+3) at 500 nM and MMA(+3) starting at 50 nM, suggesting that arsenic at these environmentally-relevant doses suppresses early T cell development through the inhibition of IL-7 signaling pathway.

  18. 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) DISRUPTS EARLY MORPHOGENETIC EVENTS THAT FORM THE LOWER REPRODUCTIVE TRACT IN FEMALE RAT FETUSES

    EPA Science Inventory

    In female rats, in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during critical periods of organogenesis causes a permanent thread of tissue across the vaginal opening, which consists of a core of mesenchyme surrounded by keratinized epithelia. The objective of t...

  19. PERSISTENT ABNORMALITIES IN THE RAT MAMMARY GLAND FOLLOWING GESTATIONAL AND LACTATIONAL EXPOSURE TO 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)

    EPA Science Inventory

    SUMMARY

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure during gestation has revealed reproductive anomalies in rat offspring, including inconclusive reports of stunted mammary development in females (Brown et al., 1998, Lewis et al., 2001). The current studies wer...

  20. Cytochrome P4501A1 is Required for Vascular Dysfunction and Hypertension Induced by 2,3,7,8-Tetrachlorodibenzo-p-dioxin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    National Health and Nutrition Examination Survey data show an association between hypertension and exposure to dioxin-like halogenated aromatic hydrocarbons (HAH). Further, chronic exposure of mice to the prototypical HAH, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), induces reactive oxygen species (...

  1. In utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure: Effects on fetal and adult cardiac gene expression and adult cardiac and renal morphology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mouse heart is a target of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during fetal development, and microarray analysis demonstrates significant changes in expression of cardiac genes involved in extracellular matrix (ECM) remodeling. We tested the hypothesis that developmental TCDD exposure wo...

  2. Hypertension, Cardiac Hypertrophy, and Impaired Vascular Relaxation Induced by 2,3,7,8-Tetrachlorodibenzo-p-Dioxin are Associated with Increased Superoxide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mechanisms by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increases the incidence of human cardiovascular disease are not known. We investigated the degree to which cardiovascular disease develops in mice following subchronic TCDD exposure. Adult male C57BL/6 mice were dosed with vehicle o...

  3. UTILIZATION OF A PBPK MODEL TO PREDICT THE DISTRIBUTION OF 2, 3, 7-8 TETRACHLORODIBENZO-P-DIOXIN (TCDD) IN HUMANS DURING CRITICAL WINDOWS OF DEVELOPMENT

    EPA Science Inventory

    Utilization of A PBPK model to predict the distribution of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) in humans during critical windows of development.
    C Emond1, MJ DeVito2 and LS Birnbaum2
    1National Research Council, US EPA, ORD, NHEERL, (ETD, PK), RTP, NC, 27711, USA 2 US...

  4. TERATOGENICITY OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) IN MICE LACKING THE EXPRESSION OF EGF AND/OR TGFALPHA

    EPA Science Inventory

    Abstract
    2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure produces hydronephrosis and cleft palate in mice. These responses are correlated with disruption of expression of epidermal growth factor (EGF) receptor ligands, primarily EGF and transforming growth factor-alpha ...

  5. SEVESO WOMEN'S HEALTH STUDY: A STUDY OF THE EFFECTS OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN ON REPRODUCTIVE HEALTH. (R824761)

    EPA Science Inventory

    Abstract

    Although reproductive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure have been reported in numerous investigations of animals, studies of this association in humans are limited. In 1976, an explosion in Seveso, Italy exposed the surround...

  6. Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) and Related Compounds: Science Advisory Board (External Review Draft) (2000)

    EPA Science Inventory

    Dioxin Reassessment, SAB Review Draft

    The U.S. Environmental Protection Agency's (EPA) is progressing toward completion of its comprehensive reassessment of dioxin science entitled, "Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibe...

  7. Defining the Borders of Dose Addition: Mixture Effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dibutyl phthalate on Male Rat Reproductive Tract Development

    EPA Science Inventory

    In utero exposure to either dibutyl phthalate (DBP) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) disrupts male rat reproductive tract differentiation. However, they act via different modes of toxicity and induce distinct postnatal phenotypes. DBP exposure decreases anogenital di...

  8. TOXICITY OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TO EARLY LIFE STAGE BROOK TROUT (SALVELINUS FONTINALIS) FOLLOWING PARTENTAL DIETARY EXPOSURE

    EPA Science Inventory

    The toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to the early life stages of F1 generation brook trout (Salvelinus fontinalis) was determined, when dosed by maternal transfer.Effects were compared across six treatments, including a control.The experimental groups, based...

  9. 2,3,7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)-MEDIATED OXIDATIVE STRESS IN FEMALE CYP1A-2 KNOCKOUT (CYP1A2-/-) MICE

    EPA Science Inventory

    2,3,7,8-Tetrachlordibenzo-p-dioxin (TCDD)-Mediated Oxidative Stress in Female CYP1A2 Knockout (CYP1A2-/-) Mice

    Deborah Burgin1, Janet Diliberto2, Linda Birnbaum2
    1UNC Toxicology; 2USEPA/ORD/NHEERL, RTP, NC

    Most of the effects due to TCDD exposure are mediated via...

  10. COMPARATIVE SENSITIVITY OF DIFFERENT LIFE-STAGES OF MEDAKA (ORYZIAS LATIPES) AND BROOK TROUT (SALVELINUS FONTINALIS) TO 2,3,7,8-TCDD

    EPA Science Inventory

    The early life stages of fish are known to be more sensitive than the adults to the toxicological effects of 2,3,7,8-tetrachlorodibenzo(p)dioxide (TCDD). TCDD concentrations in surface waters are sufficiently low that direct exposure of the developing embryo is unlikely to be o...

  11. CYP1A2 DOES NOT PLAY A CRITICAL ROLE IN 2, 3 7, 8-TETRACHLORODIBENZO-P-DIOXIN-INDUCED IMMUNOSUPRESSION

    EPA Science Inventory

    CYP1A2 IS NOT REQUIRED FOR 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN-INDUCED IMMUNOSUPPRESSION Smialowicz, Ralph J1; Burgin, Deborah E2; Williams, Wanda C1; Diliberto, Janet J1; Birnbaum, Linda S1
    1 Experimental Toxicology Division, US EPA, RTP, NC, USA; 2Curriculum in Toxicology, U...

  12. 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies

    EPA Science Inventory

    EPA invited the public to comment on the preliminary list of in vivo mammalian dose-response citations for 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). This list was compiled as a first step in the development of EPA’s response to the National Academy of Sciences comments (NAS, 2...

  13. Measurement of the water-octanol partition coefficient of 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Marple, L.; Berridge, B.; Throop, L.

    1986-04-01

    The problems inherent in the shake flask method for measurement of water-octanol partition coefficients were avoided by the use of a cell in which dioxin was allowed to diffuse from the octanol phase into the water phase. Starting from mutually presaturated water and octanol phases, dioxin equilibration appears to be complete within 1 week. Partition coefficients ranged from 3.48 x 10/sup 6/ to 8.87 x 10/sup 6/. Starting from unsaturated phases, we observed a rapid transport of dioxin from the octanol phase into the water phase, followed by a reversal that corresponds to the formation of hydrated dioxin. The average of all partition coefficient measurements for systems at equilibrium is (4.24 +/- 2.73) x 10/sup 6/, giving a log K/sub ow/ of 6.64. 12 references, 2 tables.

  14. Identification of X-ray spectra in the Na-like to O-like rubidium ions in the range of 3.8-7.3 Å

    NASA Astrophysics Data System (ADS)

    Denis-Petit, D.; Comet, M.; Bonnet, T.; Hannachi, F.; Gobet, F.; Tarisien, M.; Versteegen, M.; Gosselin, G.; Méot, V.; Morel, P.; Pain, J.-Ch.; Gilleron, F.; Frank, A.; Bagnoud, V.; Blazevic, A.; Dorchies, F.; Peyrusse, O.; Cayzac, W.; Roth, M.

    2014-11-01

    The X-rays emitted by a rubidium plasma source created by the PHELIX laser at an intensity of about 6×1014 W/cm2 were studied. The lines have been measured using Bragg crystals in the wavelength range between 3.8 and 7.3 Å and identified by means of a numerical method developed to describe highly charged rubidium ions in LTE plasma. The experimental plasma temperature, density and charge state distributions have been estimated using non-LTE codes such as CHIVAS and AVERROES. The LTE plasma temperature and density used in the calculations are those allowing to reproduce the calculated NLTE charge state distribution. In order to optimize the use of computational resources, a criterion is established to select the configurations contributing most to the spectra among all those obtained in detailed level accounting based on the MCDF code. Seventy Rb X-rays have been identified among which forty-nine are reported for the first time. The capabilities of our method are demonstrated by the good agreement of our identifications with previously published data when available.

  15. Vesicle associated membrane protein (VAMP)-7 and VAMP-8, but not VAMP-2 or VAMP-3, are required for activation-induced degranulation of mature human mast cells.

    PubMed

    Sander, Leif E; Frank, Simon P C; Bolat, Seza; Blank, Ulrich; Galli, Thierry; Bigalke, Hans; Bischoff, Stephan C; Lorentz, Axel

    2008-03-01

    Mediator release from mast cells (MC) is a crucial step in allergic and non-allergic inflammatory disorders. However, the final events in response to activation leading to membrane fusion and thereby facilitating degranulation have hitherto not been analyzed in human MC. Soluble N-ethyl-maleimide-sensitive factor attachment protein receptors (SNARE) represent a highly conserved family of proteins that have been shown to mediate intracellular membrane fusion events. Here, we show that mature MC isolated from human intestinal tissue express soluble N-ethylmaleide sensitive factor attachment protein (SNAP)-23, Syntaxin (STX)-1B, STX-2, STX-3, STX-4, and STX-6 but not SNAP-25. Furthermore, we found that primary human MC express substantial amounts of vesicle associated membrane protein (VAMP)-3, VAMP-7 and VAMP-8 and, in contrast to previous reports about rodent MC, only low levels of VAMP-2. Furthermore, VAMP-7 and VAMP-8 were found to translocate to the plasma membrane and interact with SNAP-23 and STX-4 upon activation. Inhibition of SNAP-23, STX-4, VAMP-7 or VAMP-8, but not VAMP-2 or VAMP-3, resulted in a markedly reduced high-affinity IgE receptor-mediated histamine release. In summary, our data show that mature human MC express a specific pattern of SNARE and that VAMP-7 and VAMP-8, but not VAMP-2, are required for rapid degranulation.

  16. 5,6,7,8-Tetrahydropyrido[4,3-d]pyrimidines as novel class of potent and highly selective CaMKII inhibitors.

    PubMed

    Asano, Shigehiro; Komiya, Masafumi; Koike, Nobuyuki; Koga, Erina; Nakatani, Shogo; Isobe, Yoshiaki

    2010-11-15

    A novel series of 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidines containing substituted phenyl sulfonamide are synthesized and evaluated for their inhibitory activity against CaMKII. Substituents on the phenyl group had significant impact on CaMKII inhibition, in particular, the inhibitory activity of 8p was 25-fold higher than that of KN-93, a known CaMKII inhibitor. Michaelis-Menten analysis of a representative compound suggested that the synthesized pyrimidines are calmodulin non-competitive inhibitors. Finally, 8p exhibited more than 100-fold higher selectivity for CaMKII over five types of off-target kinases. PMID:20875738

  17. 33 CFR 8.7 - Information.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Information. 8.7 Section 8.7... GUARD RESERVE § 8.7 Information. (a) Information concerning the Coast Guard Reserve may be obtained from Commandant (CG-13), 2100 2nd St. SW., Stop 7801, Washington, DC 20593-7801. (b) Information and...

  18. 33 CFR 8.7 - Information.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Information. 8.7 Section 8.7... GUARD RESERVE § 8.7 Information. (a) Information concerning the Coast Guard Reserve may be obtained from Commandant (CG-13), 2100 2nd St. SW., Stop 7801, Washington, DC 20593-7801. (b) Information and...

  19. 33 CFR 8.7 - Information.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Information. 8.7 Section 8.7... GUARD RESERVE § 8.7 Information. (a) Information concerning the Coast Guard Reserve may be obtained from Commandant (CG-13), 2100 2nd St. SW., Stop 7801, Washington, DC 20593-7801. (b) Information and...

  20. 33 CFR 8.7 - Information.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Information. 8.7 Section 8.7... GUARD RESERVE § 8.7 Information. (a) Information concerning the Coast Guard Reserve may be obtained from Commandant (CG-13), 2100 2nd St. SW., Stop 7801, Washington, DC 20593-7801. (b) Information and...

  1. 33 CFR 8.7 - Information.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Information. 8.7 Section 8.7... GUARD RESERVE § 8.7 Information. (a) Information concerning the Coast Guard Reserve may be obtained from Commandant (CG-13), 2100 2nd St. SW., Stop 7801, Washington, DC 20593-7801. (b) Information and...

  2. 22 CFR 8.7 - Security.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Security. 8.7 Section 8.7 Foreign Relations DEPARTMENT OF STATE GENERAL ADVISORY COMMITTEE MANAGEMENT § 8.7 Security. (a) All officers and members of a committee must have a security clearance for the subject matter level of security at which the...

  3. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  4. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  5. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  6. 49 CFR 7.8 - Copies

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Copies 7.8 Section 7.8 Transportation Office of the Secretary of Transportation PUBLIC AVAILABILITY OF INFORMATION Information Required To Be Made Public by DOT § 7.8 Copies Copies of any material covered by this subpart that is not published...

  7. 22 CFR 8.7 - Security.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Security. 8.7 Section 8.7 Foreign Relations DEPARTMENT OF STATE GENERAL ADVISORY COMMITTEE MANAGEMENT § 8.7 Security. (a) All officers and members of a committee must have a security clearance for the subject matter level of security at which the...

  8. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  9. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  10. Matrix metalloproteinases -1, -2, -3, -7, -8, -12, and -13 in gingival crevicular fluid during orthodontic tooth movement: a longitudinal randomized split-mouth study.

    PubMed

    Canavarro, Cristiane; Teles, Ricardo Palmier; Capelli Júnior, Jonas

    2013-10-01

    This randomized split-mouth study aimed to examine the levels of matrix metalloproteinases (MMPs) -1, -2, -3, -7, -8, -12, and -13 in the gingival crevicular fluid (GCF) at different time points during orthodontic tooth movement. A total of 16 healthy orthodontic subjects (7 females, 9 males; mean age, 17.7 years) who needed their first upper premolars extracted were enrolled. One randomly chosen maxillary canine was subjected to a distalizing force and was considered to be the test side. The contralateral canine, which was not subjected to any force but was included in the orthodontic appliance, was used as a control side. GCF sampling was performed at both the mesial (tension) and distal (pressure) test and control sites at baseline, immediately before applying the orthodontic appliance, and after 1 and 24 hours and 7, 14, and 21 days. A multiplexed bead immunoassay was used to analyse the GCF samples. The mean levels of the MMP-1, -2, -3, -7, -8, -12, and -13 were not significantly different between the test and control groups in each time showed. The comparisons between the tension and pressure sites were also not significantly different at each individual time. A few variations focused on MMP-1 and -3, but the expression of MMP-8 was higher than that of the other MMPs. MMPs are released in sufficient quantities such that tooth movement occurs but with no significant increase in GCF levels.

  11. X-ray studies of 2-amino-4-(3-nitrophenyl)-5-oxo-4,5-dihydropyrano[3,2- c] chromene-3-carbonitrile and 2-amino-7,7-dimethyl-4-(4-nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4 H-chromene-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Sharma, S.; Banerjee, B.; Brahmachari, G.; Kant, R.; Gupta, V. K.

    2015-12-01

    Two carbonitrile compounds, 2-amino-4-(3-nitrophenyl)-5-oxo-4,5-dihydropyrano[3,2- c] chromene-3-carbonitrile ( I) and 2-amino-7,7-dimethyl-4-(4-nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4 H-chromene-3-carbonitrile ( II), were synthesized, and their crystal structures were determined by X-ray diffraction technique. The crystals are triclinic, a = 7.7970(12), 8.2171(7), b = 9.0390(10), 9.2238(7), c = 15.148(2), 14.5585(11) Å, α = 81.439(10)°, 74.895(6)°, β = 75.194(12)°, 87.392(6)°, γ = 76.151(11)°, 78.552(7)°, for I and II, respectively, Z = 2, sp. gr. P overline 1. The pyran ring in both the compounds deviates significantly from planarity and adopts boat conformation. The crystal structure is stabilized by N-H···O and N-H···N hydrogen bonds.

  12. Performance assessment of Bi0.3Sr0.7Co0.3Fe0.7O3-δ-LSCF composite as cathode for intermediate-temperature solid oxide fuel cells with La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte

    NASA Astrophysics Data System (ADS)

    Khaerudini, Deni S.; Guan, Guoqing; Zhang, Peng; Hao, Xiaogang; Wang, Zhongde; Xue, Chunfeng; Kasai, Yutaka; Abudula, Abuliti

    2015-12-01

    Perovskite-type Bi0.3Sr0.7Co0.3Fe0.7O3-δ (BiSCF3737) oxide with perfectly cubic structure based on the Pm-3m space group has been developed and investigated as cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). BiSCF3737 is incorporated into (La0.6Sr0.4)0.9Co0.2Fe0.8O3±δ (LSCF) to form a composite cathode called LSCF-BiSCF. X-ray diffraction (XRD) results demonstrate that BiSCF3737 has an extremely desirable chemical compatibility with LSCF as well as with La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte. The cells with LSGM electrolyte (0.5 mm thickness) and symmetrical electrodes are fabricated for electrocatalaytic activity test. Compared with the pure constituent (LSCF or BiSCF3737), the composite with optimum composition, i.e., LSCF50-BiSCF50, exhibits better electrochemical activity for oxygen reduction. The LSGM electrolyte-supported (∼300 μm thickness) cell with LSCF50-BiSCF50 composite cathode exhibits higher power densities of 0.617 and 0.802 W cm-2 at 650 and 700 °C, respectively, with humidified H2 (∼3% H2O) as the fuel and ambient air as the oxidant. Over 78 h stability test at 600 °C indicates that a little performance decrease occurs but no interfacial damage happens, suggesting that LSCF50-BiSCF50 is a potential material for IT-SOFCs.

  13. Rapid and cost-effective analysis of 2,3,7,8-TCDD using the ``Dioxin RISc{reg_sign}`` Test Kit

    SciTech Connect

    Allen, R.L.; Stewart, T.N.; Reynolds, D.L.; Friedman, S.B.

    1994-12-31

    Current methods for detecting low levels of Dioxin are expensive and laborious. The authors have developed a rapid and sensitive enzyme immunoassay, DIOXIN RISc{reg_sign} Test Kit, for the detection of 2,3,7,8-TCDD in a variety of matrices. The immunoassay is designed to incorporate sample processing protocols which are routinely used in research and analytical laboratories. However, many of the steps used in processing dioxin samples can be eliminated because of the inherent specificity and affinity of the immunochemical reagents. The test easily detects ppt to ppq levels of 2,3,7,8-TCDD in samples which have been extracted and taken to dryness. The immunoassay shows less than 0.01% cross-reactivity with PCBs, PAHs, Chlorophenols and Chlorinated Aromatic Pesticides. The immunoassay recognizes 2,3,7-TriCDD (20%) and 2,3,7,8-TCDF (5%) but does not significantly cross-react with other Dioxin and Furan Congeners. The DIOXIN RISc{reg_sign} Test Kit offers a simple, rapid, reliable and cost-effective alternative to current methods for dioxin analysis.

  14. [The neuroprotective action of enantiomers and racemate of 2-(3,7-dioxo-2,4,6,8-tetraazabicyclo[3.3.0]oct-2-yl)-4-methylthiobutanoic acid].

    PubMed

    Kravchenko, A N; Baranov, V V; Anikina, L V; Vikharev, Iu B; Bushmarinov, I S; Neliubina, Iu V

    2012-01-01

    Neurotropic, neuroprotective and antioxidant actions of the enantiomers and the racemate of 2-(3,7-dioxo-2,4,6,8-tetraazabicyclo[3.3.0]oct-2-yl)-4-methylthiobutanoic acid were investigated. Only (+)-(S)-2-(3,7-dioxo-2,4,6,8-tetraazabicyclo[3.3.0]oct-2-yl)-4-methylthiobutanoic acid was found to have neuroprotective properties. A distereoselective synthesis of enantiomers and racemate was performed by condensations of (S), (R) and (R,S)-N-carbamoylmethionines with 4,5-dihydroxyimidazolidin-2-one (DHI), respectively. By the X-ray method, the major racemate was proved to crystallize from water as a conglomerate. No antioxidant activity was revealed.

  15. Solid-phase synthesis of 2-substituted 4-amino-7-oxo-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidines.

    PubMed

    Falcó, José L; Borrell, José I; Teixidó, Jordi

    2003-01-01

    An efficient solid-phase synthesis of 2-substituted 4-aminopyrido[2,3-d]pyrimidines 15 is reported. The procedure started by solid supporting a p-hydroxybenzaldehyde 8 to the Wang resin by using the Mitsunobu protocol. The resulting aldehyde 17 was treated with a substituted acid methyl malonate 10 to afford the corresponding alpha, beta-unsaturated ester 18, which was converted to the Michael adduct 21 by reaction with malononitrile. Cyclization of 21 with an amidine system 13 yielded the solid supported pyridopyrimidine 22, which afforded the corresponding 2-substituted 4-aminopyrido[2,3-d]pyrimidine 15 upon treatment with TFA:DCM. Compounds 15 present three diversity centers R1, R2 and R3. Having validated the chemistry on solid support, a 32-membered combinatorial library was obtained using this protocol.

  16. (9E)-9-benzylidene-2-methylsulfanyl-5-phenyl-6,7,8,9-tetrahydropyrimido[4,5-b]quinolin-4(3H)-one: a hydrogen-bonded R2(2)(8) dimer.

    PubMed

    Becerra, Diana; Insuasty, Braulio; Cobo, Justo; Glidewell, Christopher

    2013-12-15

    In the molecule of the title compound, C25H21N3OS, which was prepared by mild oxidation of the corresponding 5,6,7,8,9,10-hexahydro analogue, the fused carbocyclic ring adopts an envelope conformation. Pairs of molecules are linked into cyclic centrosymmetric dimers by pairs of inversion-related N-H···O hydrogen bonds.

  17. Hepatic estrogen receptor and plasma 17{beta}-estradiol concentrations as biomarkers of 2,3,7,8-TCDD exposure in avian hatchlings

    SciTech Connect

    Janz, D.M.; Bellward, G.D.

    1995-12-31

    The authors have been investigating the sensitivity of various toxicologically relevant endpoints as environmental biomarkers in avian hatchlings exposed in ovo to 2,3,7,8-TCDD. Potential biomarkers included various endocrine endpoints such as plasma 17{beta}-estradiol (E{sub 2}), hepatic estrogen receptor (ER) affinities and concentrations, and plasma thyroid hormones, which were compared to hepatic ethoxyresorufin O-deethylase (EROD) induction. The animal models used were domestic chickens and pigeons, and great blue herons. An experiment conducted in pigeon hatchlings compared ``early`` (embryonic day 4; E4) vs. ``late`` (E14) in ovo exposure to 1 {micro}g/kg and 3 {micro}g/kg of TCDD, respectively. Birds were sacrificed on day of hatch (H) and day 7 after hatch (D7). In the late exposure experiment, plasma E{sub 2} concentrations were reduced at H and elevated at D7 in the TCDD-exposed birds (p < 0.05). Hepatic ER concentrations were elevated at H (p < 0.01). Although EROD was half-maximally induced at H and D7 in the early exposure experiment in pigeons, there was no effect of TCDD treatment on E, or ER levels. The nominal TCDD concentration in these pigeons (1 {micro}g/kg egg) was within the range observed in wild piscivorous bird eggs collected from aquatic systems contaminated with TCDD and related chemicals (approx. 0.5--2 ng TEQ/g egg). In herons exposed to 2 {micro}g/kg of TCDD at the midpoint of incubation, hepatic ER affinities (Kd) and concentrations (Bmax) were elevated in treated birds at H (p < 0.05); however there was no effect on plasma E, levels. Liver [{sup 3}H]-TCDD concentrations were 11.3 {+-} 0.8 ng/g at H, and 0.8 {+-} 0.1 ng/g at D7, representing 9.9% and 4.9% of the nominal TCDD dose, respectively.

  18. miR-93/106b and their host gene, MCM7, are differentially expressed in leiomyomas and functionally target F3 and IL-8.

    PubMed

    Chuang, Tsai-Der; Luo, Xiaoping; Panda, Harekrushna; Chegini, Nasser

    2012-06-01

    miR-93/106b and their host gene minichromosome maintenance complex component 7 (MCM7) reside at chr7q22, a region frequently rearranged in leiomyomas. We explored the expression of miR-93/106b in leiomyoma and paired myometrium (n = 63) from untreated and patients exposed to hormonal therapies (GnRH agonist, Depo-Provera, and oral contraceptives) from African-Americans and Caucasians and their regulatory functions in isolated paired (n = 15) leiomyoma and myometrial smooth muscle cells and the leiomyosarcoma cell line. At tissue level leiomyomas expressed significantly lower levels of miR-93 and elevated MCM7 as compared with myometrium with limited racial influence or hormonal exposure on their expression. Assessing the regulatory function of miR-93/106b through doxycycline-inducible lentiviral transduction in a microarray analysis, tissue factor (F3) and IL8 were identified as their possible targets. At the tissue level, leiomyomas expressed a significantly lower level of F3 and an elevated IL-8 level, which exhibited an inverse relationship with miR-93 but with limited racial or hormonal influences. The gain of function of miR-93/106b in leiomyoma smooth muscle cells, myometrial smooth muscle cells, and the leiomyosarcoma cell line dose dependently repressed F3 and IL8 through direct interactions with their respective 3'-untranslated region and indirectly through F3 repression inhibited IL8, CTGF, and PAI-1 expression, confirmed by using small interfering RNA silencing or factor Vlla (FVIIa) activation of F3, as well as reducing the rate of proliferation, while increasing caspase-3/7 activity. We concluded that differential expression of miR-93/106b and their direct and/or indirect regulatory functions on F3, IL8, CTGF, and PAI-1 expression, with key roles in inflammation and tissue turnover may be of significance in the outcome of leiomyoma growth and associated symptoms.

  19. 7 CFR 784.8 - Appeals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Appeals. 784.8 Section 784.8 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS 2004 EWE LAMB REPLACEMENT AND RETENTION PAYMENT PROGRAM § 784.8 Appeals. The appeal...

  20. 7 CFR 735.8 - Appeals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Appeals. 735.8 Section 735.8 Agriculture Regulations... REGULATIONS FOR WAREHOUSES REGULATIONS FOR THE UNITED STATES WAREHOUSE ACT General Provisions § 735.8 Appeals. (a) Any person who is subject to an adverse determination made under the Act may appeal...

  1. 7 CFR 784.8 - Appeals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Appeals. 784.8 Section 784.8 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS 2004 EWE LAMB REPLACEMENT AND RETENTION PAYMENT PROGRAM § 784.8 Appeals. The appeal...

  2. 7 CFR 735.8 - Appeals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Appeals. 735.8 Section 735.8 Agriculture Regulations... REGULATIONS FOR WAREHOUSES REGULATIONS FOR THE UNITED STATES WAREHOUSE ACT General Provisions § 735.8 Appeals. (a) Any person who is subject to an adverse determination made under the Act may appeal...

  3. 7 CFR 784.8 - Appeals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Appeals. 784.8 Section 784.8 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS 2004 EWE LAMB REPLACEMENT AND RETENTION PAYMENT PROGRAM § 784.8 Appeals. The appeal...

  4. The thermodynamic properties of 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. [Tetrahydropyrene and hexahydropyrene

    SciTech Connect

    Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.; Steele, W.V.

    1992-12-01

    Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, vibrating-tube densitometry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical properties were estimated for both materials based on the measurement results. Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gases for selected temperatures between 380 K and 700 K. The property-measurement results reported here for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene are the first for these important intermediates in the pyrene/H[sub 2] hydrogenation reaction network.

  5. 8 CFR 1246.7 - Appeals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OF ADJUSTMENT OF STATUS § 1246.7 Appeals. Pursuant to 8 CFR part 1003, an appeal shall lie from a decision of an immigration judge under this part to the Board of Immigration Appeals. An appeal shall be... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Appeals. 1246.7 Section 1246.7 Aliens...

  6. 7,9-Diaryl-1,6,8-trioxaspiro[4.5]dec-3-en-2-ones: readily accessible and highly potent anticancer compounds.

    PubMed

    D'Erasmo, Michael P; Smith, William B; Munoz, Alberto; Mohandas, Poornima; Au, Andrew S; Marineau, Jason J; Quadri, Luis E N; Bradner, James E; Murelli, Ryan P

    2014-08-15

    7,9-Diaryl-1,6,8-trioxaspiro[4.5]dec-3-en-2-ones are a recently described group of spirocyclic butenolides that can be generated rapidly and as a single diastereomer through a cascade process between γ-hydroxybutenolides and aromatic aldehydes. The following outlines our findings that these spirocycles are potently cytotoxic and have a dramatic structure-function profile that provides excellent insight into the structural features required for this potency.

  7. Polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in fishes from Saginaw Bay, Michigan

    SciTech Connect

    Giesy, J.P.; Tillitt, D.E.; Jude, D.J.

    1997-04-01

    Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated naphthalenes (PCNs), polychlorinated dibenzothiophenes (PCDTs), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) equivalents were measured in composite samples of forage fishes and several sizes of walleyes (Stizostedion vitreum) and common carp (Cyprinus carpio) collected from Saginaw Bay, Michigan, USA. The concentrations of 2,3,7,8-TCDD equivalents determined from the use of TCDD equivalency factors (TEFs) and instrumentally determined concentrations of individual congeners were designated TEq. The 2,3,7,8-TCDD equivalents determined on the same extracts with the H4IIE bioassay were defined as TCDD-EQ. Concentrations of TCDD-EQ and TEq were significantly, but poorly correlated (R{sup 2} = 0.44). Concentrations of TCDD-EQ and TEq ranged from 10.6 to 348 and 13.5 to 69.5 ng/kg, wet weight, respectively. The ratio of TCDD-EQ to TEq ranged from 0.5 to 5.0, with the greatest ratio observed in common carp but the average ratio between TEq and TCDD-EQ was approximately 1.0. In common carp, larger walleye, and medium-sized alewife (Alosa pseudoharengus) there were significant concentrations of TCDD-EQ that could not be accounted for by TEq calculated from an additive model of PCBs, PCDDs, or PCDFs. As much as 75% of the TCDD-EQ in some samples could not be accounted for by TEqs. It is unlikely that PCNs, PCDTs, or polychlorinated diphenyl ethers (PCDEs) occurred at concentrations that were, based on their relative potencies, great enough to contribute significant quantities of TCDD-EQ. The discrepancy between TCDD-EQs and TEqs was not due to antagonisms among congeners or extraction efficiencies.

  8. A spiro[chroman-3,7'-isochromene]-4,6'(8'H)-dione from the Cordyceps-colonizing fungus Fimetariella sp.

    PubMed

    Li, Erwei; Zhang, Fan; Niu, Shubin; Liu, Xingzhong; Liu, Gang; Che, Yongsheng

    2012-07-01

    Fimetarone A (1), a metabolite with the new spiro[chroman-3,7'-isochromene]-4,6'(8'H)-dione skeleton, was isolated from cultures of the Cordyceps-colonizing fungus Fimetariella sp. Compound 1 was a 1:1 atropdiastereomeric mixture in NMR data, and aS,9S and aR,9R enantiomers were found and confirmed by X-ray crystallography. Compound 1 could be derived from the hypothetical precursors 3,4,5-trihydroxy-2-(2-methylene-3,5-dioxohexanoyl)benzoic acid (5) and lapidosin (6). PMID:22726106

  9. Stability of molybdenum nanoparticles in Sn-3.8Ag-0.7Cu solder during multiple reflow and their influence on interfacial intermetallic compounds

    SciTech Connect

    Haseeb, A.S.M.A. Arafat, M.M. Johan, Mohd Rafie

    2012-02-15

    This work investigates the effects of molybdenum nanoparticles on the growth of interfacial intermetallic compound between Sn-3.8Ag-0.7Cu solder and copper substrate during multiple reflow. Molybdenum nanoparticles were mixed with Sn-3.8Ag-0.7Cu solder paste by manual mixing. Solder samples were reflowed on a copper substrate in a 250 Degree-Sign C reflow oven up to six times. The molybdenum content of the bulk solder was determined by inductive coupled plasma-optical emission spectrometry. It is found that upon the addition of molybdenum nanoparticles to Sn-3.8Ag-0.7Cu solder, the interfacial intermetallic compound thickness and scallop diameter decreases under all reflow conditions. Molybdenum nanoparticles do not appear to dissolve or react with the solder. They tend to adsorb preferentially at the interface between solder and the intermetallic compound scallops. It is suggested that molybdenum nanoparticles impart their influence on the interfacial intermetallic compound as discrete particles. The intact, discrete nanoparticles, by absorbing preferentially at the interface, hinder the diffusion flux of the substrate and thereby suppress the intermetallic compound growth. - Highlights: Black-Right-Pointing-Pointer Mo nanoparticles do not dissolve or react with the SAC solder during reflow. Black-Right-Pointing-Pointer Addition of Mo nanoparticles results smaller IMC thickness and scallop diameter. Black-Right-Pointing-Pointer Mo nanoparticles influence the interfacial IMC through discrete particle effect.

  10. Signature of 3-4 day planetary waves in the equatorial ionospheric F layer height and medium frequency radar winds over Tirunelveli (8.7oN)

    NASA Astrophysics Data System (ADS)

    Sundararaman, Sathishkumar

    Signature of 3-4 day planetary waves in the equatorial ionospheric F layer height and medium frequency radar winds over Tirunelveli (8.7oN) S. Sathishkumar1, R. Dhanya1, K. Emperumal1, D. Tiwari2, S. Gurubaran1 and A. Bhattacharyya2 1. Equatorial Geophysical Research Laboratory, Indian Institute of Geomagnetism, Tirunelveli, India 2. Indian Institute of Geomagnetism, Navi Mumbai, India Email: sathishmaths@gmail.com Abstract The equatorial atmosphere-ionosphere system has been studied theoretically and observationally in the past. In the equatorial atmosphere, oscillations with periods of 3-4 days are often observed in the medium frequency (MF) radar over Tirunelveli (8.7oN, 77.8oE, 1.34oN geomag. lat.). Earlier observations show the clear evidence that these waves can propagate from the stratosphere to ionosphere. A digital ionosonde has been providing useful information on several ionospheric parameters from the same site. Simultaneous observations of mesospheric winds using medium frequency radar and F-layer height (h'F) from ionosonde reveal that the 3-4 day wave was evident in both the component during the 01 June 2007 and 31 July 2007. The 3-4 day wave could have an important role in the day to day variability of the equatorial ionosphere evening uplift. Results from an extensive analysis that is being carried out in the direction of 3-4 day wave present in the ionosphere will be presented.

  11. Evaluation of Inhibition Efficiency for the Detection of Captan, 2,3,7,8-Tetrachlorodibenzodioxin, Pentachlorophenol and Carbosulfan in Water: An Electrochemical Approach.

    PubMed

    Nesakumar, Noel; Ramachandra, Bhat Lakshmishri; Sethuraman, Swaminathan; Krishnan, Uma Maheswari; Rayappan, John Bosco Balaguru

    2016-02-01

    A novel bio-analytical method has been devised based on the change in catalytic activity of acetylcholinesterase (AChE) enzyme induced by captan, carbosulfan, 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and pentachlorophenol (PCP) for the investigation of inhibition efficiency and sensitivity using Pt/ZnO/AChE/Chitosan bioelectrode. The inhibition curves of captan, carbosulfan, TCDD and PCP were similar to Michaelis-Menten curve. TCDD held the minimum inhibitor Michaelis-Menten constant ([Formula: see text]) value (10.2 nM) in comparison with PCP (10.9 nM), carbosulfan (14.5 nM) and captan (7.9 × 10(3) nM). The maximum inhibition of AChE enzyme by captan was about 100 %, which was much higher than that of TCDD (72.7 %), PCP (68.1 %) and carbosulfan (47.7 %). The calculated theoretical sensitivity was in the order of TCDD > PCP > carbosulfan > captan. Comparing with TCDD (35.3 %), PCP (47.8 %) and carbosulfan (20.9 %), only the inhibition efficiency of captan (55.0 %) was the maximum. The developed bioelectrode exhibited high recovery and low relative standard deviation in local tap water samples.

  12. Racemic tricarbonyl[(4a,5,6,7,8,8a-η)-2-phenyl-3,4-dihydro-2H-1-benzopyran]chromium(0)

    PubMed Central

    van Tonder, Johannes H.; Bezuidenhoudt, Barend C. B.; Janse van Rensburg, J. Marthinus

    2010-01-01

    The title compound, [Cr(C15H14O)(CO)3], displays a distorted envelope configuration of the dihydro­pyrane ring. The dihedral angle between the phenyl and phenyl­ene rings is 50.63 (4)°. The Cr0 atom is coordinated by three CO groups and the phenyl­ene ring of the flavan ligand in an η6 mode, with a common arene-to-metal distance PMID:21588503

  13. Oxidative stress in female B6C3F1 mice following acute and subchronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

    PubMed

    Slezak, B P; Hatch, G E; DeVito, M J; Diliberto, J J; Slade, R; Crissman, K; Hassoun, E; Birnbaum, L S

    2000-04-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly persistent trace environmental contaminant and is one of the most potent toxicants known to man. Hassoun et al. (1998, Toxicol. Sci. 42, 23-27) reported an increase in the production of reactive oxygen species (ROS) in the brain of female B6C3F1 mice following subchronic exposure to TCDD at doses as low as 0.45 ng/kg/day. In the present study, oxidative stress was characterized in liver, spleen, lung, and kidney following subchronic (0.15-150 ng/kg; 5 days/week for 13 weeks, po) or acute exposure (0.001-100 microg/kg, po) to TCDD in order to investigate the interaction between tissue concentration and time for production of ROS. Seven days following acute administration of TCDD, mice were sacrificed; they demonstrated increases in liver superoxide anion production (SOAP) and thiobarbituric acid reactive substances (TBARS) at doses of 10 and 100 microg/kg, associated with hepatic TCDD concentrations of 55 and 321 ng/g, respectively. Liver obtained from mice following subchronic TCDD exposure demonstrated an increase in SOAP and TBARS above controls at doses of 150 ng/kg/day with liver TCDD concentration of only 12 ng/g. Interestingly, glutathione (GSH) levels in lung and kidney following sub-chronic TCDD exposure were decreased at the low dose of 0.15 ng/kg/day. This effect disappeared at higher TCDD doses. The data suggest that higher tissue TCDD concentrations are required to elicit oxidative stress following acute dosing than with subchronic TCDD exposure. Therefore, the mechanism of ROS production following TCDD exposure does not appear to be solely dependent upon the concentration of TCDD within the tissue. In addition, very low doses of TCDD that result in tissue concentrations similar to the background levels found in the human population produced an effect on an oxidative stress endogenous defense system. The role of this effect in TCDD-mediated toxicity is not known and warrants further investigation.

  14. 7 CFR 984.8 - Walnuts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Walnuts. 984.8 Section 984.8 Agriculture Regulations... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.8 Walnuts. Walnuts means only walnuts of the “English” (Juglans regia)...

  15. 7 CFR 984.8 - Walnuts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Walnuts. 984.8 Section 984.8 Agriculture Regulations... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.8 Walnuts. Walnuts means only walnuts of the “English” (Juglans regia)...

  16. 7 CFR 984.8 - Walnuts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Walnuts. 984.8 Section 984.8 Agriculture Regulations... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.8 Walnuts. Walnuts means only walnuts of the “English” (Juglans regia)...

  17. 7 CFR 984.8 - Walnuts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Walnuts. 984.8 Section 984.8 Agriculture Regulations... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.8 Walnuts. Walnuts means only walnuts of the “English” (Juglans regia)...

  18. 7 CFR 984.8 - Walnuts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Walnuts. 984.8 Section 984.8 Agriculture Regulations... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.8 Walnuts. Walnuts means only walnuts of the “English” (Juglans regia)...

  19. 7 CFR 1001.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1001.8 Section 1001.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.8 Nonpool plant. See § 1000.8....

  20. 7 CFR 1124.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1124.8 Section 1124.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.8 Nonpool plant. See § 1000.8....

  1. 7 CFR 1001.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1001.8 Section 1001.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1001.8 Nonpool plant. See § 1000.8....

  2. 7 CFR 1033.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1033.8 Section 1033.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1033.8 Nonpool plant. See § 1000.8....

  3. 7 CFR 1005.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1005.8 Section 1005.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.8 Nonpool plant. See § 1000.8....

  4. 7 CFR 1131.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1131.8 Section 1131.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1131.8 Nonpool plant. See § 1000.8....

  5. 7 CFR 1033.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1033.8 Section 1033.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.8 Nonpool plant. See § 1000.8....

  6. 7 CFR 1006.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1006.8 Section 1006.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1006.8 Nonpool plant. See § 1000.8....

  7. 7 CFR 1032.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1032.8 Section 1032.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1032.8 Nonpool plant. See § 1000.8....

  8. 7 CFR 1032.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1032.8 Section 1032.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.8 Nonpool plant. See § 1000.8....

  9. 7 CFR 1007.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1007.8 Section 1007.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1007.8 Nonpool plant. See § 1000.8....

  10. 7 CFR 1131.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1131.8 Section 1131.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1131.8 Nonpool plant. See § 1000.8....

  11. 7 CFR 1126.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1126.8 Section 1126.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1126.8 Nonpool plant. See § 1000.8....

  12. 7 CFR 1006.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1006.8 Section 1006.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.8 Nonpool plant. See § 1000.8....

  13. 7 CFR 1005.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1005.8 Section 1005.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1005.8 Nonpool plant. See § 1000.8....

  14. 7 CFR 1030.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1030.8 Section 1030.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1030.8 Nonpool plant. See § 1000.8....

  15. 7 CFR 1030.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1030.8 Section 1030.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1030.8 Nonpool plant. See § 1000.8....

  16. 7 CFR 1126.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1126.8 Section 1126.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.8 Nonpool plant. See § 1000.8....

  17. 7 CFR 1007.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1007.8 Section 1007.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1007.8 Nonpool plant. See § 1000.8....

  18. 7 CFR 1124.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1124.8 Section 1124.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Definitions § 1124.8 Nonpool plant. See § 1000.8....

  19. 7 CFR 1006.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1006.8 Section 1006.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1006.8 Nonpool plant. See § 1000.8....

  20. 7 CFR 1007.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1007.8 Section 1007.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.8 Nonpool plant. See § 1000.8....

  1. 7 CFR 1124.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1124.8 Section 1124.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Definitions § 1124.8 Nonpool plant. See § 1000.8....

  2. 7 CFR 1126.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1126.8 Section 1126.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1126.8 Nonpool plant. See § 1000.8....

  3. 7 CFR 1033.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1033.8 Section 1033.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1033.8 Nonpool plant. See § 1000.8....

  4. 7 CFR 1032.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1032.8 Section 1032.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1032.8 Nonpool plant. See § 1000.8....

  5. 7 CFR 1131.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1131.8 Section 1131.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.8 Nonpool plant. See § 1000.8....

  6. 7 CFR 1005.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1005.8 Section 1005.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1005.8 Nonpool plant. See § 1000.8....

  7. 7 CFR 1030.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1030.8 Section 1030.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.8 Nonpool plant. See § 1000.8....

  8. 7 CFR 1001.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1001.8 Section 1001.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Handling Definitions § 1001.8 Nonpool plant. See § 1000.8....

  9. 7 CFR 1006.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1006.8 Section 1006.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.8 Nonpool plant. See § 1000.8....

  10. 7 CFR 1001.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1001.8 Section 1001.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.8 Nonpool plant. See § 1000.8....

  11. 7 CFR 1124.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1124.8 Section 1124.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.8 Nonpool plant. See § 1000.8....

  12. 7 CFR 1131.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1131.8 Section 1131.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.8 Nonpool plant. See § 1000.8....

  13. 7 CFR 1006.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1006.8 Section 1006.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1006.8 Nonpool plant. See § 1000.8....

  14. 7 CFR 1032.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1032.8 Section 1032.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.8 Nonpool plant. See § 1000.8....

  15. 7 CFR 1126.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1126.8 Section 1126.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.8 Nonpool plant. See § 1000.8....

  16. 7 CFR 1126.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1126.8 Section 1126.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1126.8 Nonpool plant. See § 1000.8....

  17. 7 CFR 1124.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1124.8 Section 1124.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 1124.8 Nonpool plant. See § 1000.8....

  18. 7 CFR 1030.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1030.8 Section 1030.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.8 Nonpool plant. See § 1000.8....

  19. 7 CFR 1005.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1005.8 Section 1005.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.8 Nonpool plant. See § 1000.8....

  20. 7 CFR 1131.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1131.8 Section 1131.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1131.8 Nonpool plant. See § 1000.8....

  1. 7 CFR 1032.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1032.8 Section 1032.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1032.8 Nonpool plant. See § 1000.8....

  2. 7 CFR 1007.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1007.8 Section 1007.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.8 Nonpool plant. See § 1000.8....

  3. 7 CFR 1033.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1033.8 Section 1033.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.8 Nonpool plant. See § 1000.8....

  4. 7 CFR 1033.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1033.8 Section 1033.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1033.8 Nonpool plant. See § 1000.8....

  5. 7 CFR 1007.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1007.8 Section 1007.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1007.8 Nonpool plant. See § 1000.8....

  6. 7 CFR 1005.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1005.8 Section 1005.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1005.8 Nonpool plant. See § 1000.8....

  7. 7 CFR 1001.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1001.8 Section 1001.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.8 Nonpool plant. See § 1000.8....

  8. 7 CFR 1030.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1030.8 Section 1030.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1030.8 Nonpool plant. See § 1000.8....

  9. Modeling, Synthesis and Biological Evaluation of Potential Retinoid-X-Receptor (RXR) Selective Agonists: Novel Analogs of 4-[1-(3,5,5,8,8-Pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic Acid (Bexarotene) and (E)-3-(3-(1,2,3,4-tetrahydro-1,1,4,4,6-pentamethylnaphthalen-7-yl)-4-hydroxyphenyl)acrylic acid (CD3254)

    PubMed Central

    Jurutka, Peter W.; Kaneko, Ichiro; Yang, Joanna; Bhogal, Jaskaran S.; Swierski, Johnathon C.; Tabacaru, Christa R.; Montano, Luis A.; Huynh, Chanh C.; Jama, Rabia A.; Mahelona, Ryan D.; Sarnowski, Joseph T.; Marcus, Lisa M.; Quezada, Alexis; Lemming, Brittney; Tedesco, Maria A.; Fischer, Audra J.; Mohamed, Said A.; Ziller, Joseph W.; Ma, Ning; Gray, Geoffrey M.; van der Vaart, Arjan; Marshall, Pamela A.; Wagner, Carl E.

    2014-01-01

    Three unreported analogs of 4-[1-(3,5,5,8,8-pentamethyl-5-6-7-8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (1), otherwise known as bexarotene, as well as four novel analogs of (E)-3-(3-(1,2,3,4-tetrahydro-1,1,4,4,6-pentamethylnaphthalen-7-yl)-4-hydroxyphenyl)acrylic acid (CD3254) are described, and evaluated for their retinoid-X-receptor (RXR)-selective agonism. Compound 1 has FDA approval as a treatment for cutaneous T-cell lymphoma (CTCL); though, treatment with 1 can elicit side-effects by disrupting other RXR-heterodimer receptor pathways. Of the 7 modeled novel compounds, all analogs stimulate RXR-regulated transcription in mammalian-2-hybrid and RXRE-mediated assays, possess comparable or elevated biological activity based on EC50 profiles, and retain similar or improved apoptotic activity in CTCL assays compared to 1. All novel compounds demonstrate selectivity for RXR and minimal crossover onto the retinoic-acid-receptor (RAR) compared to all-trans-retinoic acid, with select analogs also reducing inhibition of other RXR-dependent pathways (e.g., VDR-RXR). Our results demonstrate that further improvements in biological potency and selectivity of bexarotene can be achieved through rational drug design. PMID:24180745

  10. Tourmaline in the 3.7-3.8 Ga Isua Supracrustal Belt, West Greenland - A window to Boron Concentrations in the Eoarchean Eon

    NASA Astrophysics Data System (ADS)

    Grew, E. S.; Dymek, R. F.; De Hoog, J. C.; Harley, S. L.; Hazen, R. M.; Yates, M. G.

    2013-12-01

    The distribution and mineralogical context of trace elements in Earth's oldest rocks provide insights on Earth's accretion, differentiation, and primordial evolution. One example is boron, which is highly concentrated in Earth's crust and oceans relative to primitive mantle, and, thus the amount of boron on Earth's surface should increase with increasing volume of crust. The earliest B mineral reported in the geological record is metamorphic tourmaline in the Isua Supracrustal Belt, where its abundance belies the notion of there being less boron in the Eoarchean than in more recent time. Chaussidon & Appel (1997, Chem. Geol., 136, 171-180) reported δ11B = --17.3 to --25.0‰ in tourmaline in Isua metachert ("conglomerate"), and δ11B = --12.6 to +5.8 ‰ on tourmaline in Isua metamorphosed mafic volcaniclastics. The large range in the latter rocks was attributed to fractionation during hydrothermal reworking, whereas the more negative values in the metacherts suggested metamorphic tourmaline formed from breakdown of clays with an average δ11B calculated to be about -8 × 7‰ deposited in an ocean having δ11B = +27×11‰, compared to +40 ‰ today, consistent with δ11B = +28‰ calculated from the Chaussidon & Albarède (1992, EPSL, 108, 229-241) model relating increase in sea-water δ11B to proportion of B extracted from Earth's mantle into the oceans and crust. This estimate of Eoarchean seawater δ11B is consistent with fractionation associated with illitization of smectite formed in a marine environment (estimated to be about --35‰) and with crystallization of metamorphic tourmaline from intergranular fluid having the same δ11B as the host metachert (another --2‰ at 500 °C based on tourmaline-water fractionation from Meyer et al. 2008, Contrib. Mineral. Petrol., 156, 259-267). However, this scenario does not adequately explain three rock types in the Isua supracrustals: (1) a tourmaline-quartz lens with ~50% modal tourmaline; (2) a dolomite

  11. Thermodynamic stability of the molecules YC2, YC3, YC4, YC5, YC6, YC7, and YC8 by high temperature Knudsen effusion mass spectrometry

    NASA Astrophysics Data System (ADS)

    Pelino, Mario; Haque, R.; Bencivenni, L.; Gingerich, K. A.

    1988-05-01

    The molecules YC2, YC3, YC4, YC5, YC6, YC7, and YC8 have been observed in a Knudsen effusion mass spectrometric investigation of the gas phase above the Y-Ir-Au-graphite system. The enthalpies ΔH○0 of the reactions Y(g)+n C(graph)=YCn(g)(n=2-8) were evaluated by the third law method; the second law method was employed for the gaseous molecules with up to six carbon atoms. The selected values of the reaction enthalpies ΔH○0 were combined with ancillary literature data to yield the atomization enthalpies ΔH○a,0 and the standard enthalpies of formation ΔH○f,298.15 in kJ mol-1 of the gaseous yttrium carbides. The values of ΔH○0 and ΔH○a,0 (in kJ mol-1) are 197±5 and 1225±8 for YC2; 377±10 and 1757±12 for YC3; 361±8 and 2484±10 for YC4; 499±10 and 3057±15 for YC5; 536±15 and 3731±20 for YC6; 684±35 and 4294±35 for YC7, and 693±35 and 4727±35 for YC8. The values of ΔH○f,298.15 (in kJ mol-1) are 623±8, 804±12, 790±10, 924±15, 966±20, 1105±35, and 1124±35 for YCn (n=2-8), respectively.

  12. Comparisons of the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on chemically impacted and nonimpacted subpopulations of Fundulus heteroclitus. 2: Metabolic considerations

    SciTech Connect

    Prince, R.; Cooper, K.R.

    1995-04-01

    A previous paper reported resistance to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity in a subpopulation of Fundulus heteroclitus inhabiting the chemically impacted estuary of Newark Bay, New Jersey, as compared to a chemically nonimpacted subpopulation of F. heteroclitus in Tuckerton, New Jersey. This paper reports the results of toxicokinetic and metabolic investigations. The rate of [{sup 3}H]TCDD elimination following a single dermal treatment of [{sup 3}H]TCDD were similar between the Newark and Tuckerton F. heteroclitus subpopulations, as were the capabilities to metabolize TCDD. The Newark F. heteroclitus subpopulation consistently exhibited elevated hepatic P4501A catalytic activity (two- to fivefold), as measured by ethoxyresorufin O-deethylase (EROD), compared to the Tuckerton subpopulation. EROD activity in Newark F. heteroclitus could not be induced by dermally administered [{sup 3}H]TCDD, ranging from 0.020 to 8.0 ng/g [{sup 3}H]TCDD. The Tuckerton fish exhibited a linear increase in EROD activity at 96 h following dermal administration of [{sup 3}H]TCDD, ranging from 0.80 to 8.0 ng/g [{sup 3}H]TCDD. The maximum mean induction in the Tuckerton fish was 30-fold greater than the Tuckerton vehicle control mean. These data indicate that the Newark fish were resistant to both the toxicity of TCDD and the ability of TCDD to induce P4501A activity, which may imply an alteration in the Ah receptor complex of Newark F. heteroclitus.

  13. A densitometric analysis of IIaO film flown aboard the space shuttle transportation system STS #3, 7, and 8

    NASA Technical Reports Server (NTRS)

    Hammond, Ernest C., Jr.

    1989-01-01

    Since the United States of America is moving into an age of reusable space vehicles, both electronic and photographic materials will continue to be an integral part of the recording techniques available. Film as a scientifically viable recording technique in astronomy is well documented. There is a real need to expose various types of films to the Shuttle environment. Thus, the main objective was to look at the subtle densitometric changes of canisters of IIaO film that was placed aboard the Space Shuttle 3 (STS-3).

  14. A diversity oriented, microwave assisted synthesis of N-substituted 2-hydro-4-amino-pyrido[2,3-d]pyrimidin-7(8H)-ones.

    PubMed

    Mont, Núria; Teixidó, Jordi; Borrell, José I

    2009-02-01

    A protocol for the synthesis of N-substituted 2-hydro-4-amino-pyrido[2,3-d]pyrimidin-7(8H)-ones (11) is described. Thus, the formylation of a 2-aminopyridone 12 in 85% formic acid/Ac(2)O, proceeding via in situ cyclization to the intermediate formamide 13, affords the corresponding 2-hydro-4-oxo-pyridopyrimidine 14, which is converted to a 4-chloro-pyridopyrimidine 15 upon treatment with POCl(3). The subsequent transformation to the title compounds is carried by treatment with the corresponding amine in MeOH under microwave irradiation conditions.

  15. Civic Education Curriculum Grades 3 and 4 [and] Civic Culture Curriculum Grade 7 [and] Civic Culture Curriculum Grade 8.

    ERIC Educational Resources Information Center

    Georgescu, Dakmara; Stefanescu, Doina-Olga; Nazdravan, Mihai; Chiritescu, Dorina; Lacatus, Maria-Liana

    This guide begins by stating that the curricular items recommended for civic education classes meet the provisions of Romania's Education Law, articles 3 and 4, and particularly, the educational ideal and the ultimate goals of education. Noting that the process of socialization should start early in life, the guide states that the place of civic…

  16. 7 CFR 7.8 - Conduct of community committee elections.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Conduct of community committee elections. 7.8 Section... STABILIZATION AND CONSERVATION STATE, COUNTY AND COMMUNITY COMMITTEES § 7.8 Conduct of community committee elections. (a) The county committee serving at the time shall be responsible for the conduct of...

  17. 7 CFR 7.8 - Conduct of community committee elections.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Conduct of community committee elections. 7.8 Section... STABILIZATION AND CONSERVATION STATE, COUNTY AND COMMUNITY COMMITTEES § 7.8 Conduct of community committee elections. (a) The county committee serving at the time shall be responsible for the conduct of...

  18. Mechanism of action of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on intermediary metabolism in the rat

    SciTech Connect

    Lakshman, M.R.; Ghosh, P.; Chirtel, S.J. )

    1991-03-11

    The effects of three days of exposure to a single 20 {mu}g/kg dosage of TCDD on fat mobilization and the fates of the mobilized fatty acids and glycerol were determined. It was found that TCDD caused a significant mobilization of depot fat into the plasma compartment resulting in 1.5-2.8 fold increase in plasma free-fatty acid concentrations. The same treatment of TCDD caused a 32% inhibition of the rate of hepatic oleate oxidation to CO{sub 2} without significantly affecting the rate of fatty acid esterification to triglycerides. In contrast, hepatic ketogenic rate from oleate and octanoate was markedly stimulated by 85% and 69% respectively. These results support the concept that although the translocation of long chain fatty acids from the outer mitochondrial membrane into the inner mitochondrial membrane via the carnitine pathway and their subsequent beta-oxidation of the fatty acids must be working normally, their complete oxidation to CO{sub 2}via the TCA cycle is impaired. At the same time, TCDD seems to preferentially divert the acetyl CoA generated from the beta-oxidation of fatty acids to the ketogenic pathway. Surprisingly, TCDD treatment inhibited the hepatic ketogenic rate from glycerol by 21% and its oxidation by 31% without affecting its esterification.

  19. 3,4,7,8-Tetra­methyl-1,10-phenanthrolin-1-ium nitrate monohydrate

    PubMed Central

    Zhang, Ke-Jie; Zhang, Yan-Fang

    2012-01-01

    In the crystal of the title compound, C16H17N2 +·NO3 −·H2O, the tetra­methyl-1,10-phenanthrolinium cations, nitrate anions and lattice water mol­ecules are all located on a mirror plane with the methyl H atoms of the cation equally disordered over two sites about the mirror plane. The cation, anion and water mol­ecule are linked by O—H⋯O and N—H⋯O hydrogen bonds into a sheet parallel to the bc plane. π–π stacking between phenanthroline ring systems is observed in the crystal structure, the centroid–centroid distance being 3.4745 (6) Å. PMID:22719684

  20. 7 CFR 295.8 - Requests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Requests. 295.8 Section 295.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... Regulations 7 CFR 1.6 and addressed to the appropriate FNS official listed below: (1) Food Stamp...

  1. 7 CFR 295.8 - Requests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Requests. 295.8 Section 295.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... Regulations 7 CFR 1.6 and addressed to the appropriate FNS official listed below: (1) Food Stamp...

  2. 7 CFR 295.8 - Requests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Requests. 295.8 Section 295.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... Regulations 7 CFR 1.6 and addressed to the appropriate FNS official listed below: (1) Food Stamp...

  3. 7 CFR 295.8 - Requests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Requests. 295.8 Section 295.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... Regulations 7 CFR 1.6 and addressed to the appropriate FNS official listed below: (1) Food Stamp...

  4. 7 CFR 295.8 - Requests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Requests. 295.8 Section 295.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... Regulations 7 CFR 1.6 and addressed to the appropriate FNS official listed below: (1) Food Stamp...

  5. Uptake and tissue distribution of waterborne [{sup 3}H]-2,3,7,8-tetrachlorodibenzo-p-dioxin in embryonic fathead minnow (Pimephales promelas)

    SciTech Connect

    Winden, P.J.J. de; Herwig, H.J.

    1995-12-31

    Accumulation of [{sup 3}H]tetrachlorodibenzo-p-dioxin ([{sup 3}H]-TCDD) was studied in embryos of fathead minnow (Pimephales promelas), to evaluate this species` high sensitivity to this compound in relation to internal concentrations. Pathological alterations during fathead minnow early development were described previously at aqueous concentrations ranging from 0.1--50 ng/l. Fertilized eggs and developing embryos were exposed to [{sup 3}H]TCDD (32 mCi/{micro}mol) in 100 ml of water (24 hour static-renewal procedure), until onset of hatch. With 24 hour intervals, radioactivity was measured in exposure water and embryos using liquid scintillation counting. Radioactivity in embryonic tissue was determined in whole body homogenates, obtained by extraction with Lumasolve. Collection of outcoming air from the ventilated exposure medium in aceton revealed no loss of TCDD as a result of evaporation. Binding of TCDD to glass, however, appeared considerable and highly variable (25--50% after 24 hrs). [{sup 3}H]-TCDD levels in exposure water declined from 10 ng/l to < 1 ng/l in 24 hrs (reduction of 85--90%). Fathead minnow eggs or embryos (N = 60), exposed to an initial level of 10 ng [{sup 3}H]TCDD/l, accumulated approximately 3--15% of the applied toxicant in a 24 hr period. During 5 days of exposure (daily medium refreshment), uptake of TCDD increased linearly from 1--2 pg/embryo (day 1) to 9--10 pg/embryo (day 5). Hatching took place in fresh water, resulting in some elimination of TCDD to a level of 6--7 pg/embryo at day 6. The present data demonstrate high toxicity of TCDD in fathead minnow early life stages. At day 3 of embryonic development, accumulation of 5--7 pg [{sup 3}H]-TCDD per embryo causes severe hemodynamic disturbances. Microautoradiography is currently applied to study tissue distribution of [{sup 3}H]-TCDD during embryogenesis.

  6. A honeycomb network based on hybrid lanthanum complexes encircling a [β-Mo8O26]4- isomer: Synthesis, characterization and crystal structure of [La (η2-NO3) (dmso)7]2 [β-Mo8O26

    NASA Astrophysics Data System (ADS)

    Khélifa, Arbia Ben; Ezzayani, Khaireddine; Belkhiria, Mouhamed Salah

    2016-10-01

    A novel isopolymolybdates functionalized by rare earth complexes namely, [La (η2-NO3) (dmso)7]2 [β-Mo8O26] (1) has been successfully synthesized and characterized by routine methods: IR, X-ray powder diffraction, UV-Visible absorption and single crystal X-ray diffraction. The title compound is crystallized in monoclinic space group P21/n with a = 11.566 (2) Å, b = 28.522 (6) Å, c = 12.644 (3) Å, β = 91.94 (3)°. The structural feature of 1 is that lanthanum complexes form a honeycomb network, in which resides the [β-Mo8O26]4- isomer. The cohesion structure is ensured by non typical hydrogen bonding interactions causes a 3D supramolecular network. Absorption spectrum, optical band gap energies have been investigated.

  7. Potency of 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126), alone and in combination with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), to produce lake trout early life-stage mortality

    SciTech Connect

    Zabel, E.W.; Peterson, R.E.; Cook, P.M.

    1995-12-01

    Newly fertilized lake trout (Salvelinus namaycush) eggs were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126), or their combination, and sac fry mortality was used to determine toxic potencies. The toxic equivalency factor (TEF) for PCB 126 was 0.0030. The dose-response curve for the PCB 126/TCDD mixture based on TCDD toxic equivalents was not significantly different from that for TCDD alone, suggesting additivity between the two congeners in causing sac fry mortality.

  8. 7 CFR 1709.8 - Electronic submission.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Electronic submission. 1709.8 Section 1709.8... AGRICULTURE ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements § 1709.8 Electronic submission... announcement and grant agreements or if other regulations provide for electronic submission. Any...

  9. 7 CFR 1709.8 - Electronic submission.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Electronic submission. 1709.8 Section 1709.8... AGRICULTURE ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements § 1709.8 Electronic submission... announcement and grant agreements or if other regulations provide for electronic submission. Any...

  10. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  11. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  12. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  13. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  14. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  15. 7 CFR 624.8 - Assistance.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Assistance. 624.8 Section 624.8 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE WATER RESOURCES EMERGENCY WATERSHED PROTECTION § 624.8 Assistance. (a) Sponsors must submit...

  16. 7 CFR 624.8 - Assistance.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Assistance. 624.8 Section 624.8 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE WATER RESOURCES EMERGENCY WATERSHED PROTECTION § 624.8 Assistance. (a) Sponsors must submit...

  17. 7 CFR 1424.8 - Payment amounts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Payment amounts. 1424.8 Section 1424.8 Agriculture... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOENERGY PROGRAM § 1424.8 Payment amounts. (a) An eligible producer may be paid the amount specified in this section, subject to the availability of funds....

  18. 7 CFR 1424.8 - Payment amounts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Payment amounts. 1424.8 Section 1424.8 Agriculture... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOENERGY PROGRAM § 1424.8 Payment amounts. (a) An eligible producer may be paid the amount specified in this section, subject to the availability of funds....

  19. 7 CFR 1424.8 - Payment amounts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Payment amounts. 1424.8 Section 1424.8 Agriculture... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOENERGY PROGRAM § 1424.8 Payment amounts. (a) An eligible producer may be paid the amount specified in this section, subject to the availability of funds....

  20. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a)...

  1. 7 CFR 17.8 - Ocean transportation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Ocean transportation. 17.8 Section 17.8 Agriculture... THE AGRICULTURAL TRADE DEVELOPMENT AND ASSISTANCE ACT OF 1954, AS AMENDED § 17.8 Ocean transportation. (a) General. (1) This section applies to the financing of ocean freight or ocean freight...

  2. 7 CFR 17.8 - Ocean transportation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Ocean transportation. 17.8 Section 17.8 Agriculture... THE AGRICULTURAL TRADE DEVELOPMENT AND ASSISTANCE ACT OF 1954, AS AMENDED § 17.8 Ocean transportation. (a) General. (1) This section applies to the financing of ocean freight or ocean freight...

  3. 7 CFR 17.8 - Ocean transportation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Ocean transportation. 17.8 Section 17.8 Agriculture... THE AGRICULTURAL TRADE DEVELOPMENT AND ASSISTANCE ACT OF 1954, AS AMENDED § 17.8 Ocean transportation. (a) General. (1) This section applies to the financing of ocean freight or ocean freight...

  4. 7 CFR 17.8 - Ocean transportation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Ocean transportation. 17.8 Section 17.8 Agriculture... THE AGRICULTURAL TRADE DEVELOPMENT AND ASSISTANCE ACT OF 1954, AS AMENDED § 17.8 Ocean transportation. (a) General. (1) This section applies to the financing of ocean freight or ocean freight...

  5. 7 CFR 1000.8 - Nonpool plant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Nonpool plant. 1000.8 Section 1000.8 Agriculture... Definitions § 1000.8 Nonpool plant. Nonpool plant means any milk receiving, manufacturing, or processing plant other than a pool plant. The following categories of nonpool plants are further defined as follows:...

  6. 7 CFR 1000.8 - Nonpool plant.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Nonpool plant. 1000.8 Section 1000.8 Agriculture... Definitions § 1000.8 Nonpool plant. Nonpool plant means any milk receiving, manufacturing, or processing plant other than a pool plant. The following categories of nonpool plants are further defined as follows:...

  7. 7 CFR 1000.8 - Nonpool plant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Nonpool plant. 1000.8 Section 1000.8 Agriculture... Definitions § 1000.8 Nonpool plant. Nonpool plant means any milk receiving, manufacturing, or processing plant other than a pool plant. The following categories of nonpool plants are further defined as follows:...

  8. 7 CFR 1416.8 - Appeals.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Appeals. 1416.8 Section 1416.8 Agriculture... General Provisions for 2006 Emergency Agricultural Disaster Assistance Programs § 1416.8 Appeals. The appeal regulations set forth at parts 11 and 780 of this title apply to determinations made pursuant...

  9. 7 CFR 1416.8 - Appeals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Appeals. 1416.8 Section 1416.8 Agriculture... General Provisions for 2006 Emergency Agricultural Disaster Assistance Programs § 1416.8 Appeals. The appeal regulations set forth at parts 11 and 780 of this title apply to determinations made pursuant...

  10. 7 CFR 12.8 - Affiliated persons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Affiliated persons. 12.8 Section 12.8 Agriculture Office of the Secretary of Agriculture HIGHLY ERODIBLE LAND AND WETLAND CONSERVATION General Provisions § 12.8 Affiliated persons. (a) Ineligibility of affiliated persons. Ineligibility of an individual...

  11. 7 CFR 12.8 - Affiliated persons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Affiliated persons. 12.8 Section 12.8 Agriculture Office of the Secretary of Agriculture HIGHLY ERODIBLE LAND AND WETLAND CONSERVATION General Provisions § 12.8 Affiliated persons. (a) Ineligibility of affiliated persons. Ineligibility of an individual...

  12. 7 CFR 623.8 - Easement value.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Easement value. 623.8 Section 623.8 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE WATER RESOURCES EMERGENCY WETLANDS RESERVE PROGRAM § 623.8 Easement value. NRCS offers...

  13. 7 CFR 12.8 - Affiliated persons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Affiliated persons. 12.8 Section 12.8 Agriculture Office of the Secretary of Agriculture HIGHLY ERODIBLE LAND AND WETLAND CONSERVATION General Provisions § 12.8 Affiliated persons. (a) Ineligibility of affiliated persons. Ineligibility of an individual...

  14. 7 CFR 12.8 - Affiliated persons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Affiliated persons. 12.8 Section 12.8 Agriculture Office of the Secretary of Agriculture HIGHLY ERODIBLE LAND AND WETLAND CONSERVATION General Provisions § 12.8 Affiliated persons. (a) Ineligibility of affiliated persons. Ineligibility of an individual...

  15. 7 CFR 1.8 - Multitrack processing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Multitrack processing. 1.8 Section 1.8 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Official Records § 1.8 Multitrack processing. (a) When an agency has a significant number of requests, the nature of which precludes...

  16. 7 CFR 1437.8 - Unit definition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Unit definition. 1437.8 Section 1437.8 Agriculture... Provisions § 1437.8 Unit definition. (a) The unit identifies the interest of the producer in the administrative county on the basis of the unique relationship of the owner to one or more operators. The unit...

  17. 7 CFR 1290.8 - Grant agreements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Grant agreements. 1290.8 Section 1290.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM § 1290.8 Grant agreements. (a) After review and approval of a grant application, AMS will enter into...

  18. 7 CFR 1291.8 - Grant agreements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Grant agreements. 1291.8 Section 1291.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM-FARM BILL § 1291.8 Grant agreements. (a) After approval of a grant application, AMS will enter into...

  19. 7 CFR 1291.8 - Grant agreements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Grant agreements. 1291.8 Section 1291.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM-FARM BILL § 1291.8 Grant agreements. (a) After approval of a grant application, AMS will enter into...

  20. 7 CFR 1290.8 - Grant agreements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Grant agreements. 1290.8 Section 1290.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM § 1290.8 Grant agreements. (a) After review and approval of a grant application, AMS will enter into...

  1. 7 CFR 3401.8 - Grant awards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Grant awards. 3401.8 Section 3401.8 Agriculture... RESEARCH GRANTS PROGRAM General § 3401.8 Grant awards. (a) General. Within the limit of funds available for such purpose, the awarding official shall make research project grants to those responsible,...

  2. 7 CFR 1291.8 - Grant agreements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Grant agreements. 1291.8 Section 1291.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM-FARM BILL § 1291.8 Grant agreements. (a) After approval of a grant application, AMS will enter into...

  3. 7 CFR 3401.8 - Grant awards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Grant awards. 3401.8 Section 3401.8 Agriculture... RESEARCH GRANTS PROGRAM General § 3401.8 Grant awards. (a) General. Within the limit of funds available for such purpose, the awarding official shall make research project grants to those responsible,...

  4. 7 CFR 1290.8 - Grant agreements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Grant agreements. 1290.8 Section 1290.8 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SPECIALTY CROP BLOCK GRANT PROGRAM § 1290.8 Grant agreements. (a) After review and approval of a grant application, AMS will enter into...

  5. 7 CFR 1000.8 - Nonpool plant.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Nonpool plant. 1000.8 Section 1000.8 Agriculture... Definitions § 1000.8 Nonpool plant. Nonpool plant means any milk receiving, manufacturing, or processing plant other than a pool plant. The following categories of nonpool plants are further defined as follows:...

  6. 7 CFR 1000.8 - Nonpool plant.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Nonpool plant. 1000.8 Section 1000.8 Agriculture... Definitions § 1000.8 Nonpool plant. Nonpool plant means any milk receiving, manufacturing, or processing plant other than a pool plant. The following categories of nonpool plants are further defined as follows:...

  7. 7 CFR 1.8 - Multitrack processing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Multitrack processing. 1.8 Section 1.8 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Official Records § 1.8 Multitrack processing. (a) When an agency has a significant number of requests, the nature of which precludes...

  8. 7 CFR 356.8 - Return procedure.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Return procedure. 356.8 Section 356.8 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FORFEITURE PROCEDURES § 356.8 Return procedure. If, at the conclusion...

  9. 7 CFR 3200.8 - Costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Costs. 3200.8 Section 3200.8 Agriculture Regulations... PERSONAL PROPERTY § 3200.8 Costs. Excess personal property obtained under this part is provided free of charge. However, the institution must pay all costs associated with packaging and transportation....

  10. 7 CFR 3200.8 - Costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Costs. 3200.8 Section 3200.8 Agriculture Regulations... PERSONAL PROPERTY § 3200.8 Costs. Excess personal property obtained under this part is provided free of charge. However, the institution must pay all costs associated with packaging and transportation....

  11. 7 CFR 11.8 - Division hearings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Division hearings. 11.8 Section 11.8 Agriculture Office of the Secretary of Agriculture NATIONAL APPEALS DIVISION National Appeals Divison Rules of Procedures § 11.8 Division hearings. (a) General rules. (1) The Director, the Hearing Officer, and...

  12. 7 CFR 1400.8 - Equitable treatment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Equitable treatment. 1400.8 Section 1400.8... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.8 Equitable treatment. (a... Administrator deems necessary to provide fair and equitable treatment to such person or legal entity....

  13. 7 CFR 1400.8 - Equitable treatment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Equitable treatment. 1400.8 Section 1400.8... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.8 Equitable treatment. (a... Administrator deems necessary to provide fair and equitable treatment to such person or legal entity....

  14. 7 CFR 1400.8 - Equitable treatment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Equitable treatment. 1400.8 Section 1400.8... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.8 Equitable treatment. (a... Administrator deems necessary to provide fair and equitable treatment to such person or legal entity....

  15. 7 CFR 1400.8 - Equitable treatment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Equitable treatment. 1400.8 Section 1400.8... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.8 Equitable treatment. (a... Administrator deems necessary to provide fair and equitable treatment to such person or legal entity....

  16. 7 CFR 1400.8 - Equitable treatment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Equitable treatment. 1400.8 Section 1400.8... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.8 Equitable treatment. (a... Administrator deems necessary to provide fair and equitable treatment to such person or legal entity....

  17. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Scrap. 30.8 Section 30.8 Agriculture Regulations of... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap.... Scrap which accumulates from handling unstemmed leaf tobacco is known as leaf-scrap, and scrap...

  18. 7 CFR 47.8 - The answer.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false The answer. 47.8 Section 47.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... UNDER THE PERISHABLE AGRICULTURAL COMMODITIES ACT Rules Applicable to Reparation Proceedings § 47.8...

  19. 7 CFR 47.8 - The answer.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false The answer. 47.8 Section 47.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... UNDER THE PERISHABLE AGRICULTURAL COMMODITIES ACT Rules Applicable to Reparation Proceedings § 47.8...

  20. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office...

  1. 7 CFR 1778.8 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 12 2013-01-01 2013-01-01 false 1778.8 Section 1778.8 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.8...

  2. 7 CFR 1778.8 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false 1778.8 Section 1778.8 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.8...

  3. 7 CFR 1778.8 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true 1778.8 Section 1778.8 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.8...

  4. 7 CFR 1778.8 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false 1778.8 Section 1778.8 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.8...

  5. 7 CFR 1778.8 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 12 2012-01-01 2012-01-01 false 1778.8 Section 1778.8 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.8...

  6. 7 CFR 3434.8 - Appeals.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Appeals. 3434.8 Section 3434.8 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION PROCESS § 3434.8 Appeals. (a) An...

  7. 7 CFR 3434.8 - Appeals.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Appeals. 3434.8 Section 3434.8 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION PROCESS § 3434.8 Appeals. (a) An...

  8. 7 CFR 1773.8 - Audit date.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false Audit date. 1773.8 Section 1773.8 Agriculture... (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Audit Requirements § 1773.8 Audit date. (a) The annual audit must be performed as of the end of the same calendar month each year unless prior approval...

  9. 7 CFR 3402.8 - Fellowship activities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Fellowship activities. 3402.8 Section 3402.8... AGRICULTURE FOOD AND AGRICULTURAL SCIENCES NATIONAL NEEDS GRADUATE AND POSTGRADUATE FELLOWSHIP GRANTS PROGRAM Program Description § 3402.8 Fellowship activities. A USDA Graduate Fellow shall be enrolled as a...

  10. 7 CFR 3402.8 - Fellowship activities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Fellowship activities. 3402.8 Section 3402.8... AGRICULTURE FOOD AND AGRICULTURAL SCIENCES NATIONAL NEEDS GRADUATE AND POSTGRADUATE FELLOWSHIP GRANTS PROGRAM Program Description § 3402.8 Fellowship activities. A USDA Graduate Fellow shall be enrolled as a...

  11. 7 CFR 3402.8 - Fellowship activities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Fellowship activities. 3402.8 Section 3402.8... AGRICULTURE FOOD AND AGRICULTURAL SCIENCES NATIONAL NEEDS GRADUATE AND POSTGRADUATE FELLOWSHIP GRANTS PROGRAM Program Description § 3402.8 Fellowship activities. A USDA Graduate Fellow shall be enrolled as a...

  12. 7 CFR 3402.8 - Fellowship activities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Fellowship activities. 3402.8 Section 3402.8... AGRICULTURE FOOD AND AGRICULTURAL SCIENCES NATIONAL NEEDS GRADUATE AND POSTGRADUATE FELLOWSHIP GRANTS PROGRAM Program Description § 3402.8 Fellowship activities. A USDA Graduate Fellow shall be enrolled as a...

  13. 7 CFR 27.8 - Director.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Director. 27.8 Section 27.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Administration § 27.8 Director. The Director...

  14. 7 CFR 27.8 - Director.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Director. 27.8 Section 27.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Administration § 27.8 Director. The Director...

  15. 7 CFR 27.8 - Director.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Director. 27.8 Section 27.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Administration § 27.8 Director. The Director...

  16. 7 CFR 27.8 - Director.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Director. 27.8 Section 27.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Administration § 27.8 Director. The Director...

  17. Ethyl 2,7,7-trimethyl-4-(1-methyl-1H-indol-3-yl)-5-oxo-1,4,5,6,7,8-hexa-hydro-quinoline-3-carboxyl-ate.

    PubMed

    Oztürk Yildirim, Sema; Butcher, Ray J; Gündüz, Miyase Gözde; El-Khouly, Ahmed; Simşek, Rahime; Safak, Cihat

    2013-01-01

    In the title mol-ecule, C24H28N2O3, the cyclo-hexene ring is in a sofa conformation and the 1,4-dihydro-pyridine ring is in a slight boat conformation. In the indole ring system, the pyrrole and benzene rings form a dihedral angle of 2.63 (7)°. In the crystal, N-H⋯O hydrogen bonds connect the mol-ecules into C(6) chains parallel to the b axis and pairs of weak C-H⋯O hydrogen bonds link inversion-related chains into a ladder motif through R2(2)(18) rings. A weak intra-molecular C-H⋯O hydrogen bond is also observed. PMID:23476426

  18. Early life stage toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in zebrafish (Danio rerio)

    SciTech Connect

    Henry, T.R.; Hornung, M.W.; Abnet, C.C.; Peterson, R.E.

    1995-12-31

    TCDD and related compounds cause toxicity in fish early life stages, characterized by edema, regional ischemia, craniofacial malformations, growth retardation and mortality. Determining the mechanism of these effects requires understanding normal early life stage development, which has been studied extensively in the zebrafish. Establishing zebrafish as a model for TCDD developmental toxicity requires demonstration that TCDD adversely affects zebrafish early life stages. Toxicity of TCDD to zebrafish early life stages was characterized by exposing newly fertilized eggs for 1 hr to water containing acetone or graded concentrations of [{sup 3}H]-TCDD and observed for signs of toxicity at 12 hr intervals for 240 hr post fertilization (hpf). TCDD did not increase embryo mortality during the egg stage (0--48 hpf) nor did it affect the time to hatching (48--96 hpf). At the highest TCDD egg doses (4.5--6.5 ng/g) the earliest sign of toxicity was pericardial edema (72 hpf) followed by the onset of yolk sac edema (96 hpf) onset of mortality (132 hpf). At lower egg doses the same effects were seen but after a longer delay period. Other signs of toxicity included craniofacial malformations, cranial edema and loss of swimming activity prior to death. To determine the dose-response relationship for pericardial and yolk sac edema and larval mortality the cumulative incidence of each effect was determined at 240 hpf. The ED{sub 50}s (95% fiducial limits) for pericardial edema and yolk sac edema were 2.1 6 (1.82--2.48) and 2.43 (2.12--2.72) ng TCDD/g egg, respectively. The LD{sub 50} was 2.45 (1.94--2.89) ng TCDD/g egg. In conclusion, the signs of TCDD early life stage toxicity in zebrafish are essentially identical to those in other fish species, however, larger egg doses of TCDD are required to elicit the effects.

  19. 4-(8-Quinolyl)amino-7-nitro-2,1,3-benzoxadiazole as a new colorimetric probe for rapid and visual detection of Hg2+

    NASA Astrophysics Data System (ADS)

    Wang, Ke; Yang, Lixue; Zhao, Chuan; Ma, Huimin

    2013-03-01

    4-Amino-7-nitro-2,1,3-benzoxadiazole (ANBD) usually serves as a scaffold for developing fluorescent probes. In this paper, however, ANBD has been used as a chromogenic unit to design a new colorimetric probe, 4-(8-quinolyl)amino-7-nitro-2,1,3-benzoxadiazole (1), for rapid and visual detection of Hg2+. The reaction of 1 with Hg2+ in NaH2PO4-Na2HPO4 buffer (pH 7.0) containing 70% (v/v) acetonitrile forms a 1:1 complex, accompanying a red shift of the absorption maximum from 482 nm to 557 nm and a distinct color change from orange to violet. Moreover the color reaction exhibits a high selectivity and sensitivity to Hg2+ only, instead of other common metal ions. This behavior may be ascribed to the formation of a specific 1-Hg2+ complex, which is supported by 1H NMR titration experiments. The present study is not only a supplement to the detection method of Hg2+, but also a merit to the chemistry of 4-amino-7-nitro-2,1,3-benzoxadiazole.

  20. Selective synthesis of [7]- and [8]cycloparaphenylenes.

    PubMed

    Sibbel, Friederike; Matsui, Katsuma; Segawa, Yasutomo; Studer, Armido; Itami, Kenichiro

    2014-01-28

    Cycloparaphenylenes (CPPs) are a remarkable class of hoop-shaped conjugated macrocycles with inimitable properties. Herein we describe a divergent synthesis of [7]CPP and [8]CPP. Furthermore we present the first crystal structure of [7]CPP. Thus, we have now established the size-selective synthesis of [n]CPP (n = 7-16) in a uniformed cyclohexane-based method. PMID:24310620

  1. 8 CFR 286.7 - Penalties.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Penalties. 286.7 Section 286.7 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION USER FEE § 286.7 Penalties. Failure of any air or sea carrier to comply with the provisions of section 286 of the Act and this...

  2. 8 CFR 286.7 - Penalties.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Penalties. 286.7 Section 286.7 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION USER FEE § 286.7 Penalties. Failure of any air or sea carrier to comply with the provisions of section 286 of the Act and this...

  3. 8 CFR 286.7 - Penalties.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Penalties. 286.7 Section 286.7 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION USER FEE § 286.7 Penalties. Failure of any air or sea carrier to comply with the provisions of section 286 of the Act and this...

  4. 8 CFR 286.7 - Penalties.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Penalties. 286.7 Section 286.7 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION USER FEE § 286.7 Penalties. Failure of any air or sea carrier to comply with the provisions of section 286 of the Act and this...

  5. 8 CFR 286.7 - Penalties.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Penalties. 286.7 Section 286.7 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION USER FEE § 286.7 Penalties. Failure of any air or sea carrier to comply with the provisions of section 286 of the Act and this...

  6. Exocrine pancreatic pathology in female Harlan Sprague-Dawley rats after chronic treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin and dioxin-like compounds.

    PubMed Central

    Nyska, Abraham; Jokinen, Micheal P; Brix, Amy E; Sells, Donald M; Wyde, Michael E; Orzech, Denise; Haseman, Joseph K; Flake, Gordon; Walker, Nigel J

    2004-01-01

    We evaluated the effect of chronic exposure to dioxin and dioxin-like compounds on the pancreas in female Harlan Sprague-Dawley rats. This investigation represents part of an ongoing National Toxicology Program initiative to determine the relative potency of chronic toxicity and carcinogenicity of polychlorinated dioxins, furans, and biphenyls. Animals were treated by gavage for up to 2 years with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3,4,4,5-pentachlorobiphenyl (PCB-126), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or a toxic-equivalency-factor (TEF) mixture of these agents; control animals received corn oil-acetone vehicle alone. A complete necropsy was performed on all animals, and a full complement of tissues was collected and examined microscopically. Administration of each of the four compounds was associated with increased incidences of several nonneoplastic changes in the exocrine pancreas, including cytoplasmic vacuolation, chronic active inflammation, atrophy, and arteritis. Low incidences, but higher than those in the historical database, of pancreatic acinar adenoma and carcinoma were seen in the TCDD, PeCDF, and TEF-mixture groups. These results indicate that the pancreatic acini are target tissues for dioxin and certain dioxin-like compounds. Key words: carcinogenesis, dioxin, furans, inflammation, pancreas, polychlorinated biphenyls. PMID:15175180

  7. Crystal structure of (1R,3S,8R,11R)-11-acetyl-3,7,7-trimethyl-10-oxatri­cyclo­[6.4.0.01,3]dodecan-9-one

    PubMed Central

    Bismoussa, Abdoullah; Ait Itto, My Youssef; Daran, Jean-Claude; Auhmani, Abdelwahed; Auhmani, Aziz

    2015-01-01

    The title compound, C16H24O3, is built up from three fused rings, a six-membered, a seven-membered and a three-membered ring. The absolute configuration of the title compound was determined as (1R,3S,8R,11R) based on the synthetic pathway. The six-membered ring has an half-chair conformation whereas the seven-membered ring displays a boat conformation. In the cyrstal, C—H⋯O hydrogen bonds build up a two-dimensional network parallel to (0 0 1). The crystal studied was an inversion twin with a minor twin component of 34%. PMID:26870471

  8. Nrf2 protects against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced oxidative injury and steatohepatitis

    SciTech Connect

    Lu Hong; Cui Wei; Klaassen, Curtis D.

    2011-10-15

    Previous studies demonstrate that Nrf2, a master regulator of antioxidative responses, is essential in mediating induction of many antioxidative enzymes by acute activation of the AhR. However, the role of Nrf2 in protecting against oxidative stress and DNA damage induced by sustained activation of the AhR remains unknown and was investigated herein. Tissue and blood samples were collected from wild-type (WT) and Nrf2-null mice 21 days after administration of a low-toxic dose (10 {mu}g/kg ip) of TCDD. Only Nrf2-null mice lost body weight after TCDD treatment; however, blood levels of ALT were not markedly changed in either genotype, indicating a lack of extensive necrosis. Compared to livers of TCDD-treated WT mice, livers of TCDD-treated Nrf2-null mice had: 1) degenerated hepatocytes, lobular inflammation, marked fat accumulation, and higher mRNA expression of inflammatory and fibrotic genes; 2) depletion of glutathione, elevation in lipid peroxidation and marker of DNA damage; 3) attenuated induction of phase-II enzymes Nqo1, Gsta1/2, and Ugt2b35 mRNAs, but higher induction of cytoprotective Ho-1, Prdx1, Trxr1, Gclc, and Epxh1 mRNAs; 4) higher mRNA expression of Fgf21 and triglyceride-synthesis genes, but down-regulation of bile-acid-synthesis genes and cholesterol-efflux transporters; and 5) trend of induction/activation of c-jun and NF-kB. Additionally, TCDD-treated Nrf2-null mice had impaired adipogenesis in white adipose tissue. In conclusion, Nrf2 protects livers of mice against oxidative stress, DNA damage, and steatohepatitis induced by TCDD-mediated sustained activation of the AhR. The aggravated hepatosteatosis in TCDD-treated Nrf2-null mice is due to increased lipogenesis in liver and impaired lipogenesis in white adipose tissue. - Highlights: > TCDD causes hepatosteatosis and induction of Nrf2-target genes in wild-type mice. > TCDD causes weight loss, oxidative injury, and steatohepatitis in Nrf2-null mice. > Livers of TCDD-treated Nrf2-null mice have

  9. Photolytic method for destruction of dioxins in liquid laboratory waste and identification of the photoproducts from 2,3,7,8-TCDD

    SciTech Connect

    Konstantinov, A.D.; Johnston, A.M.; Cox, B.J.; Petrulis, J.R.; Orzechowski, M.T.; Bunce, N.J.; Tashiro, C.H.M.; Chittim, B.G.

    2000-01-01

    Analytical and other research laboratories that generate small volumes of dioxin-containing wastes have no convenient method for their disposal. The authors have used ultraviolet photolysis with a low-pressure mercury lamp to destroy dioxin-like compounds, both as individual congeners and in actual waste analytical samples, down to nondetect levels. Photolysis promises to be an efficient, safe, and inexpensive method for on-site treatment of liquid laboratory wastes that are contaminated by dioxin-like compounds, allowing the treated materials to be discarded as regular organic solvent waste. Experiments with 1,6-[{sup 3}H]-2,3,7,8-TCDD revealed that the principal photolytic pathway involves cleavage of C-O bonds rather than C-Cl bonds, giving chlorinated hydroxydiphenyl ethers as the initial products and accounting for the low material balances of reductive dechlorination products previously found upon photolysis of PCDDs. The photolysis products from 2,3,7,8-TCDD do not bind to either the Ah receptor or the estrogen receptor in vitro, making it unlikely that the products from UV treatment of PCDD/PCDF in laboratory waste will show either Ah or estrogen receptor-mediated toxicological effects.

  10. 40 CFR 721.5288 - Chromate(2-), [3-hydroxy-4-[(2-hydroxy-1-naphthenyl)azo]-7-nitro-1-substituted][N-[7-hydroxy-8...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...] -1-substituted]-, salt (generic). 721.5288 Section 721.5288 Protection of Environment ENVIRONMENTAL...-substituted]-, salt (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as chromate(2-), -7- nitro-1-substituted] -1-substituted]-,...

  11. Pharmacokinetics of ( sup 125 I)-2-iodo-3,7,8-trichlorodibenzo-p-dioxin in mice: Analysis with a physiological modeling approach

    SciTech Connect

    Leung, H.W.; Poland, A.; Paustenbach, D.J.; Murray, F.J.; Andersen, M.E. )

    1990-05-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent inducer of hepatic microsomal enzymes. The influence of an inducing dose of TCDD on tissue distribution and other pharmacokinetic behavior of a TCDD analog in the mice was examined by employing a high specific activity radioligand. (125I)-2-iodo-3,7,8-trichlorodibenzo-p-dioxin (ITCDD). Female C57BL/6J mice were pretreated with 0.1 mumol/kg of TCDD or the vehicle only, followed by 0.1 nmol ITCDD/kg 3 days later. The control animals had the highest concentration of ITCDD-derived radioactivity in the fat, but the TCDD-pretreated animals had the highest concentration in their livers. Whole-body elimination of ITCDD approximated first-order behavior, and induction by pretreatment with the inducing dose of TCDD almost doubled the rate of excretion (control mice, t1/2 = 14.2 days; pretreated mice, t1/2 = 8.0 days). All disposition results in naive and pretreated mice were satisfactorily described by a consistent physiologically based pharmacokinetic model in which induction increased the amount of microsomal ITCDD-binding protein from 1.75 to 20 nmol/liver and increased the rate constant for metabolism of free ITCDD from 1 to 3/hr/kg liver. The binding affinity of the microsomal ITCDD-binding protein was the same (20 nM) in both induced and noninduced mice. Model simulations indicated a time delay in the elimination of nonparent ITCDD metabolites from the body and a more rapid absorption of the parent ligand in the pretreated mice. Consistent with previous physiological modeling with TCDD in different mouse strains, the primary factor influencing the liver/fat concentration ratio appears to be the affinity and capacity of the microsomal TCDD-binding proteins, which are altered by induction.

  12. Structurally Similar Triphenylphosphine-Stabilized Undecagolds, Au11(PPh3)7Cl3 and [Au11(PPh3)8Cl2]Cl, Exhibit Distinct Ligand Exchange Pathways with Glutathione

    PubMed Central

    2015-01-01

    Ligand exchange is frequently used to introduce new functional groups on the surface of inorganic nanoparticles or clusters while preserving the core size. For one of the smallest clusters, triphenylphosphine (TPP)-stabilized undecagold, there are conflicting reports in the literature regarding whether core size is retained or significant growth occurs during exchange with thiol ligands. During an investigation of these differences in reactivity, two distinct forms of undecagold were isolated. The X-ray structures of the two forms, Au11(PPh3)7Cl3 and [Au11(PPh3)8Cl2]Cl, differ only in the number of TPP ligands bound to the core. Syntheses were developed to produce each of the two forms, and their spectroscopic features correlated with the structures. Ligand exchange on [Au11(PPh3)8Cl2]Cl yields only small clusters, whereas exchange on Au11(PPh3)7Cl3 (or mixtures of the two forms) yields the larger Au25 cluster. The distinctive features in the optical spectra of the two forms made it possible to evaluate which of the cluster forms were used in the previously published papers and clarify the origin of the differences in reactivity that had been reported. The results confirm that reactions of clusters and nanoparticles may be influenced by small variations in the arrangement of ligands and suggest that the role of the ligand shell in stabilizing intermediates during ligand exchange may be essential to preventing particle growth or coalescence. PMID:25171178

  13. Toxicity and disposition of 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF) in the rhesus monkey (Macaca mulatta)

    SciTech Connect

    Brewster, D.W.; Elwell, M.R.; Birnbaum, L.S.

    1988-04-01

    The toxicity and disposition of 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF), a ubiquitous and acutely toxic environmental contaminant, was examined in three adult male Rhesus monkeys administered a single iv dose of 34 micrograms (0.1 mumol)/kg. Within 20 min, 4PeCDF was eliminated from the blood and was distributed to the liver, skin, adipose, and muscle tissues. Excretion occurred primarily via the feces with a minimum whole body half-life approximately 38 days. Within 7-14 days after administration, the packed cell volume and serum triglyceride and bile acid concentrations were significantly increased while serum cholesterol, protein, and albumin concentrations were decreased relative to pretreatment levels. Thyroid hormone levels were also altered with an increase in TSH and a decrease in T3 and T4 concentrations. After 28 days, two monkeys began exhibiting alopecia, hyperkeratinization of the toe and finger nails, facial chloracne-like lesions, and loss of body weight. They subsequently died 40 and 48 days after treatment. Similar symptoms of toxicity were observed in the third animal 58 days after 4PeCDF administration, but this animal appeared to fully recover and was administered 4PeCDF orally and (3H)1,2,3,7,8-pentachloro-dibenzofuran (1PeCDF) dermally 238 days after the initial iv dose. In this animal, approximately 2% of an oral dose of (14C)-4PeCDF was absorbed from the stomach and small intestine in 6 hr and was distributed mainly to the muscle and skin and less than 99% of a dermal dose of 1PeCDF remained at the site of application. Pathological findings in the monkeys that died indicated hyperplastic and metaplastic changes in the gastric mucosa, the Meibomian glands of the eyelid, and the ceruminous glands of the ear. Regression of these lesions was present in the surviving animal.

  14. Orientation-dependent energy level alignment and film growth of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on HOPG.

    PubMed

    Lyu, Lu; Niu, Dongmei; Xie, Haipeng; Cao, Ningtong; Zhang, Hong; Zhang, Yuhe; Liu, Peng; Gao, Yongli

    2016-01-21

    Combining ultraviolet photoemission spectroscopy, X-ray photoemission spectroscopy, atomic force microscopy, and X-ray diffraction measurements, we performed a systematic investigation on the correlation of energy level alignment, film growth, and molecular orientation of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on highly oriented pyrolytic graphite. The molecules lie down in the first layer and then stand up from the second layer. The ionization potential shows a sharp decrease from the lying down region to the standing up region. When C8-BTBT molecules start standing up, unconventional energy level band-bending-like shifts are observed as the film thickness increases. These shifts are ascribed to gradual decreasing of the molecular tilt angle about the substrate normal with the increasing film thickness.

  15. Orientation-dependent energy level alignment and film growth of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on HOPG

    NASA Astrophysics Data System (ADS)

    Lyu, Lu; Niu, Dongmei; Xie, Haipeng; Cao, Ningtong; Zhang, Hong; Zhang, Yuhe; Liu, Peng; Gao, Yongli

    2016-01-01

    Combining ultraviolet photoemission spectroscopy, X-ray photoemission spectroscopy, atomic force microscopy, and X-ray diffraction measurements, we performed a systematic investigation on the correlation of energy level alignment, film growth, and molecular orientation of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on highly oriented pyrolytic graphite. The molecules lie down in the first layer and then stand up from the second layer. The ionization potential shows a sharp decrease from the lying down region to the standing up region. When C8-BTBT molecules start standing up, unconventional energy level band-bending-like shifts are observed as the film thickness increases. These shifts are ascribed to gradual decreasing of the molecular tilt angle about the substrate normal with the increasing film thickness.

  16. Carcinogenesis Bioassay of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (CAS No. 1746-01-6) in Swiss-Webster Mice (Dermal Study).

    PubMed

    1982-02-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin occurs as a highly toxic impurity found in herbicides containing 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4,5-T- derivatives, as well as in other chemicals synthesized using 2,4,5-trichlorophenol. The herbicide 2,4,5-T has been marketed in the United States since 1948. Production increased sharply between 1960 and 1970 when a 1:1 mixture of 2,4,5-T and 2,4-dichlorophenoxyacetic acid (2,4-D) was used as a defoliant in Vietnam under the names of "herbicide agent orange, herbicide orange, agent orange, and orange". During this 10-year period, about 106 million pounds of 2,4,5-T were sprayed. A carcinogenesis bioassay was conducted by applying an acetone suspension of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to the clipped backs of 30 male and female Swiss-Webster mice 3 days per week for 99 or 104 weeks. Similar groups were pretreated with 1 application of 50 &mgr;g dimethylbenzanthracene (DMBA) in 0.1 ml acetone 1 week before TCDD administration began. Female mice received 0.005 &mgr;g TCDD per application, and the male mice received 0.001 &mgr;g TCDD. As vehicle controls, 45 mice of each sex received 0.1 ml acetone three times per week. Thirty animals of each sex were used as untreated controls. Throughout the bioassay, mean body weights of the male and female mice administered TCDD, or TCDD following DMBA, were essentially the same as those of the corresponding vehicle control group. Mean body weights of dosed and vehicle control groups of males were less thanthose of the untreated control group throughout the study; for the females, mean body weights were less than the untreated controls during the first 80 weeks. In female mice, the incidences of fibrosarcoma in the integumentary system in dosed groups with TCDD were significantly (P=0.007) higher than that in the corresponding controls (2/41, 5%; 8/27, 30%). An increase in the same tumor type, although not statistically significant (P=0.084), was also observed in

  17. Carcinogenesis Bioassay of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (CAS No. 1746-01-6) in Swiss-Webster Mice (Dermal Study).

    PubMed

    1982-02-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin occurs as a highly toxic impurity found in herbicides containing 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4,5-T- derivatives, as well as in other chemicals synthesized using 2,4,5-trichlorophenol. The herbicide 2,4,5-T has been marketed in the United States since 1948. Production increased sharply between 1960 and 1970 when a 1:1 mixture of 2,4,5-T and 2,4-dichlorophenoxyacetic acid (2,4-D) was used as a defoliant in Vietnam under the names of "herbicide agent orange, herbicide orange, agent orange, and orange". During this 10-year period, about 106 million pounds of 2,4,5-T were sprayed. A carcinogenesis bioassay was conducted by applying an acetone suspension of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to the clipped backs of 30 male and female Swiss-Webster mice 3 days per week for 99 or 104 weeks. Similar groups were pretreated with 1 application of 50 &mgr;g dimethylbenzanthracene (DMBA) in 0.1 ml acetone 1 week before TCDD administration began. Female mice received 0.005 &mgr;g TCDD per application, and the male mice received 0.001 &mgr;g TCDD. As vehicle controls, 45 mice of each sex received 0.1 ml acetone three times per week. Thirty animals of each sex were used as untreated controls. Throughout the bioassay, mean body weights of the male and female mice administered TCDD, or TCDD following DMBA, were essentially the same as those of the corresponding vehicle control group. Mean body weights of dosed and vehicle control groups of males were less thanthose of the untreated control group throughout the study; for the females, mean body weights were less than the untreated controls during the first 80 weeks. In female mice, the incidences of fibrosarcoma in the integumentary system in dosed groups with TCDD were significantly (P=0.007) higher than that in the corresponding controls (2/41, 5%; 8/27, 30%). An increase in the same tumor type, although not statistically significant (P=0.084), was also observed in

  18. Effects of 3,3',4,4',5-pentachlorobiphenyl and 2,3,7,8-tetrachlorodibenzo-p-dioxin injected into the yolks of double-crested cormorant (Phalacrocorax auritus) eggs prior to incubation

    USGS Publications Warehouse

    Powell, D.C.; Aulerich, R.J.; Meadows, J.C.; Tillitt, D.E.; Kelly, M.E.; Stromborg, K.L.; Melancon, M.J.; Fitzgerald, S.D.; Bursian, S.J.

    1998-01-01

    Double-crested cormorant (Phalacrocorax auritus) eggs were injected with either 3,3',4,4',5-pentachlorobiphenyl (polychlorinated biphenyl [PCB] 126; 70-698 ?g/kg egg) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 1.3-11.7 ?g/kg egg) prior to incubation. These compounds were injected into the yolks of cormorant eggs collected from incomplete clutches at isolated colonies on Lake Winnipegosis, Manitoba, Canada. Eggs were incubated for approximately 26 to 28 d. After hatching the brain, bursa, heart, liver, and spleen were dissected and weighed. Torsos were preserved in formalin for examination of the gonads. Median lethal doses (LD50s) calculated from mortality data at hatching were 177 and 4.0 ?g/kg egg for PCB 126 and TCDD, respectively. No significant differences were found in the incidence of developmental abnormalities in any of the treatment groups. Bursa weights were significantly less in the greatest (11.7 ?g/kg egg) TCDD group compared to the vehicle control group. Spleen weights were significantly less in the 349 ?g PCB 126/kg egg and the 5.4 and 11.7 ?g TCDD/kg egg groups when compared to the vehicle control group. No histological alterations of the gonads were found. Hepatic ethoxyresorufin-O-deethylase activity in all PCB 126 and TCDD dose groups was significantly greater compared to the control activity. The toxic equivalency factor for PCB 126 was 0.02

  19. Molecular characterization of mutation and comparison of mutation profiles in the hprt gene of Chinese hamster ovary cells treated with benzo[a]pyrene trans-7,8-diol-anti-9,10-epoxide, 1-nitrobenzol[a]pyrene trans-7,8-diol-anti-9,10-epoxide, and 3-nitrobenzol[a]pyrene trans-7,8-diol-anti-9,10-epoxide

    SciTech Connect

    Zhan, D.J.; Heflich, R.H.; Fu, P.P.

    1996-12-31

    Both 1- and 3-nitrobenzol[a] pyrene (nitro-BaP) are environmental contaminants, potent mutagens in Salmonella, and moderate mutagens in Chinese hamster ovary (CHO) cells. The mutagenicity of their oxidized metabolites, trans-7,8-dihydroxy-anti-9, 10-epoxy-7,8,9,10-tetrahydro-1-nitrobenzol[a]pyrene (1-nitro-BaP-DE) and trans-7,8-dihydroxy-anti-9, 10-epoxy-7,8,9,10-tetrahydro-3-nitrobenzo[a]pyrene (3-nitro-BaP-DE), together with trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydrobenzol[a]pyren (BaP-DE), was determined in CHO-K1 cells, and the resulting mutations at the hprt locus were characterized by polymerase chain reaction (PCR) amplification of reverse-transcribed hprt mRNA, followed by DNA sequence analysis. The mutant frequencies, in mutants/10{sup 6} clonable cells, at 30 and 100 ng/ml, were BaP-DE, 248 and 456; 1-nitro-BaP-DE, 68 and 260; 3-nitro-BaP-DE, 81 and 232, respectively. In general, the three diolepoxides exhibited similar mutational spectra: (1) 64% (23/36 sequenced mutants) of BaP-DE, 53% (19/36) of 1-nitro-BaP-DE, and 64% (23/36) of 3-nitro-BaP-DE mutants resulted from simple base pair substitution, with the predominant mutation being G{r_arrow}T transversion: (2) 90%, 100%, and 100% of mutations at G:C had the mutated dG on the nontranscribed DNA strand; and (3) about one quarter of the mutants produced by each mutagen had one or more PCR products with partial or complete exon deletions. 61 refs., 1 fig., 7 tabs.

  20. 7 CFR 27.8 - Director.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Director. 27.8 Section 27.8 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS...

  1. 7 CFR 246.8 - Nondiscrimination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Nondiscrimination. 246.8 Section 246.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL SUPPLEMENTAL NUTRITION PROGRAM FOR WOMEN, INFANTS AND CHILDREN Participant Eligibility §...

  2. 7 CFR 246.8 - Nondiscrimination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Nondiscrimination. 246.8 Section 246.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS SPECIAL SUPPLEMENTAL NUTRITION PROGRAM FOR WOMEN, INFANTS AND CHILDREN Participant Eligibility §...

  3. 7 CFR 1230.8 - Delegate Body.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Delegate Body. 1230.8 Section 1230.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Body. Delegate Body means the National Pork Producers Delegate Body established pursuant to § 1230.30....

  4. 7 CFR 1230.8 - Delegate Body.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Delegate Body. 1230.8 Section 1230.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Body. Delegate Body means the National Pork Producers Delegate Body established pursuant to § 1230.30....

  5. 7 CFR 275.8 - Review coverage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Review coverage. 275.8 Section 275.8 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Management Evaluation...

  6. 7 CFR 623.8 - Easement value.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... land covered by the easements. Fair market value will be based on post-flood conditions as if reclaimed... 7 Agriculture 6 2010-01-01 2010-01-01 false Easement value. 623.8 Section 623.8 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT...

  7. 7 CFR 1215.8 - Industry information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Industry information. 1215.8 Section 1215.8... Industry information. Industry information means information and programs that will lead to the development of new markets, new marketing strategies, or increased efficiency for the popcorn industry,...

  8. 7 CFR 1215.8 - Industry information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Industry information. 1215.8 Section 1215.8... Industry information. Industry information means information and programs that will lead to the development of new markets, new marketing strategies, or increased efficiency for the popcorn industry,...

  9. 7 CFR 1215.8 - Industry information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Industry information. 1215.8 Section 1215.8... Industry information. Industry information means information and programs that will lead to the development of new markets, new marketing strategies, or increased efficiency for the popcorn industry,...

  10. 7 CFR 1215.8 - Industry information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Industry information. 1215.8 Section 1215.8... Industry information. Industry information means information and programs that will lead to the development of new markets, new marketing strategies, or increased efficiency for the popcorn industry,...

  11. New lithium copper borates with BO3 triangles: Li6CuB4O10, Li3CuB3O7, Li8Cu7B14O32, and Li2Cu9B12O28.

    PubMed

    Kuratieva, N V; Bànki, M; Tsirlin, A A; Eckert, J; Ehrenberg, H; Mikhailova, D

    2013-12-16

    Crystal structures of three new lithium copper borates, Li3CuB3O7, Li8Cu7B14O32, and Li2Cu9B12O28, and a new Li6CuB4O10 polymorph were solved by single-crystal X-ray diffraction. In all of the structures, the boron cations form BO3 triangles, which are connected with each other and with copper polyhedra only via corners in Li6CuB4O10 and Li3CuB3O7 and via both corners and edges in Li8Cu7B14O32 and Li2Cu9B12O28. The Li3CuB3O7 and Li8Cu7B14O32 compounds were synthesized as pure samples with only trace amounts of impurities; hence, their magnetic properties could be investigated and analyzed in terms of underlying magnetic couplings. Other compositions always represented multiphase mixtures. Li3CuB3O7 features infinite Cu,O chains formed by Cu2O6 units consisting of edge-shared CuO4 squares. Together with two apical oxygen atoms with long interatomic Cu-O distances of 2.7-2.8 Å, the Cu2O6 units form chains extended along the a axis. These pseudochains are responsible for strong anisotropic thermal expansion behavior. The temperature dependence of the magnetization between 4 and 380 K for Li3CuB3O7 could be fit well by a spin-dimer model. The magnetic susceptibility of Li8Cu7B14O32 showed a more complex temperature dependence, with two different Curie-Weiss regimes in the temperature range of 2-380 K. PMID:24266792

  12. Characterization of the Pathogenesis of H10N3, H10N7, and H10N8 Subtype Avian Influenza Viruses Circulating in Ducks

    PubMed Central

    Zhang, Miaomiao; Zhang, Xingxing; Xu, Kaidi; Teng, Qiaoyang; Liu, Qinfang; Li, Xuesong; Yang, Jianmei; Xu, Jianqing; Chen, Hongjun; Zhang, Xiaoyan; Li, Zejun

    2016-01-01

    Three H10 subtype avian influenza viruses were isolated from domestic ducks in China, designated as SH602/H10N8, FJ1761/H10N3 and SX3180/H10N7, with an intravenous pathogenicity index (IVPI) of 0.39, 1.60, and 1.27, respectively. These H10 viruses showed a complex pathology pattern in different species, although full genome characterizations of the viruses could not identify any molecular determinant underlying the observed phenotypes. Our findings describe the pathobiology of the three H10 subtype AIVs in chickens, ducks, and mice. FJ1761/H10N3 evolved E627K and Q591K substitutions in the gene encoding the PB2 protein in infected mice with severe lung damage, suggesting that H10 subtype avian influenza viruses are a potential threat to mammals. PMID:27678170

  13. X-ray diffraction on (AgI)0.7- (NaPO3)0.3 and (AgI)0.8- (NaPO3)0.2 composites

    SciTech Connect

    Purwanto, A. . E-mail: purwanto@centrin.net.id; Kartini, E.; Sakuma, T.; Collins, M.F.; Kamiyama, T.

    2005-01-04

    We have identified the crystallographic phases of the melt-quenched superionic composites (AgI)0.7- (NaPO3)0.3 and (AgI)0.8- (NaPO3)0.2 by X-ray diffraction. Measurements were made in a temperature range from 300 to 630 deg. K. The materials have a glass phase and one or more crystalline phases. At 300 deg. K and at 350-bar K, the crystalline phase contains a 30:70 mixture of {beta}AgI and {gamma}AgI. Above 350 deg. K, the fraction of {beta}AgI increases and at 403-bar K it is the dominant phase with a {beta}{gamma} ratio of about 70:30 (slightly less in (AgI)0.8- (NaPO3)0.2). At 453, 523 and 623 deg. K the crystalline material is mainly {alpha}AgI. Crystalline 16-silver dodecaiodide diphosphate (Ag16I12P2O7) is also present between 373 and 523 deg. K at a 5-10% level. It disappears at 623-bar K because the crystal melts.

  14. Ultrasound Mediated One-Pot, Three Component Synthesis, Docking and ADME Prediction of Novel 5-Amino-2-(4-chlorophenyl)-7-Substituted Phenyl-8,8a-dihydro-7H-(1,3,4)thiadiazolo(3,2-α)pyrimidine-6-carbonitrile Derivatives as Anticancer Agents.

    PubMed

    Tiwari, Shailee V; Seijas, Julio A; Vazquez-Tato, M Pilar; Sarkate, Aniket P; Lokwani, Deepak K; Nikalje, Anna Pratima G

    2016-01-01

    Herein, we report an environmentally friendly, rapid, and convenient one-pot ultrasound-promoted synthesis of 5-amino-2-(4-chlorophenyl)-7-substituted phenyl-8,8a-dihydro-7H-(1,3,4)thiadiazolo(3,2-α)pyrimidine-6-carbonitrile derivatives. The in-vitro anticancer activities of these compounds were evaluated against four human tumor cell lines. Among all the synthesized derivatives, compound 4i, which has substituent 3-hydroxy-4-methoxyphenyl is found to have the highest GI50 value of 32.7 μM, 55.3 μM, 34.3 μM, 28.9 μM for MCF-7, K562, HeLa and PC-3 cancer cell lines respectively. A docking study of the newly synthesized compounds were performed, and the results showed good binding mode in the active site of thymidylate synthase enzyme. ADME properties of synthesized compounds were also studied and showed good drug like properties. PMID:27483213

  15. Revised structural phase diagram of (Ba{sub 0.7}Ca{sub 0.3}TiO{sub 3})-(BaZr{sub 0.2}Ti{sub 0.8}O{sub 3})

    SciTech Connect

    Keeble, Dean S.; Thomas, Pam A.; Benabdallah, Feres; Maglione, Mario; Kreisel, Jens

    2013-03-04

    The temperature-composition phase diagram of barium calcium titanate zirconate (x(Ba{sub 0.7}Ca{sub 0.3}TiO{sub 3})-(1 - x)(BaZr{sub 0.2}Ti{sub 0.8}O{sub 3}); BCTZ) has been reinvestigated using high-resolution synchrotron x-ray powder diffraction. Contrary to previous reports of an unusual rhombohedral-tetragonal phase transition in this system, we have observed an intermediate orthorhombic phase, isostructural to that present in the parent phase, BaTiO{sub 3}, and we identify the previously assigned T-R transition as a T-O transition. We also observe the O-R transition coalescing with the previously observed triple point, forming a phase convergence region. The implication of the orthorhombic phase in reconciling the exceptional piezoelectric properties with the surrounding phase diagram is discussed.

  16. Periodicity Dependence of the Built-in Electric Field in (Ba0.7Ca0.3)TiO3/Ba(Zr0.2Ti0.8)O3 Ferroelectric Superlattices.

    PubMed

    Lin, Qianru; Wang, Danyang; Chen, Zhigang; Liu, Wenfeng; Lim, Sean; Li, Sean

    2015-12-01

    Symmetric ferroelectric superlattices consisting of (Ba0.7Ca0.3)TiO3 (BCT) and Ba(Zr0.2Ti0.8)O3 (BZT) layers were successfully grown on La0.7Sr0.3MnO3 electroded (001)-oriented SrTiO3 substrates by laser molecular beam epitaxy. With the monitor of reflective high-energy electron diffraction, the growth mode and rate were precisely controlled to realize the desired superlattice periodicity as confirmed by both X-ray diffraction and transmission electron microscopy results. The microscopic piezoelectric response and macroscopic ferroelectric properties were investigated as a function of periodicity of the BCTm/BZTm (m = 3, 5, 10, and 15 unit cells) superlattices. The existence of a built-in electric field was confirmed in all the superlattices and its strength was highly dependent on the periodicity. The excellent tunability of built-in electric field opens a path for designing microelectronic devices with various functionalities based on BCTm/BZTm superlattices.

  17. Induction of benzo(a)pyrene metabolism by 2,3,7,8-tetrachlorodibenzo-p-dioxin in primary cultures of adult rat hepatocytes: regulation by vitamin A

    SciTech Connect

    Steward, A.R.

    1982-01-01

    In order to develop a cellular model for studying mechanisms of enzyme induction and the effects of this induction on xenobiotic metabolism and cytotoxicity, the induction of benzo(a)pyrene (BaP) metabolism by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was investigated in primary hepatocyte cultures prepared from adult male rats and maintained in chemically-defined medium containing hormones. A derepression of induction was observed during the first 3 days in culture. Addition of 0.8 to 2.0 ..mu..g/ml of retinol acetate (RA) prevented about half of the derepression of induction occurring between 36 and 60 h in culture. Horse serum (10%) also blocked up to half of the observed derepression. Serum, however, also led to a 40% reduction in the partitioning of (/sup 3/H)TCDD from the medium into the hepatocytes. The derepresion of MFO induction in primary adult hepatocyte cultures may occur partly as a result of a deficiency of retinol. RA is hypothesized to slow the time course of induction by reducing the rate of protein turnover. RA may also partially block the shift in the dose-response curve for induction by TCDD by maintaining the normal metabolic regulation of the cytosolic receptor for TCDD. Addition of a physiological level of RA to the culture medium may therefore help to maintain the hepatocytes at a level of genetic expression more nearly representative of the intact liver.

  18. Determination of 5-log reduction times for Escherichia coli O157:H7, Salmonella enterica, or Listeria monocytogenes in acidified foods with pH 3.5 or 3.8 3.

    PubMed

    Breidt, F; Kay, K; Cook, J; Osborne, J; Ingham, B; Arritt, F

    2013-07-01

    A critical factor in ensuring the safety of acidified foods is the establishment of a thermal process that assures the destruction of acid-resistant vegetative pathogenic and spoilage bacteria. For acidified foods such as dressings and mayonnaises with pH values of 3.5 or higher, the high water phase acidity (acetic acid of 1.5 to 2.5% or higher) can contribute to lethality, but there is a lack of data showing how the use of common ingredients such as acetic acid and preservatives, alone or in combination, can result in a 5-log reduction for strains of Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in the absence of a postpackaging pasteurization step. In this study, we determined the times needed at 10° C to achieve a 5-log reduction of E. coli O157:H7, S. enterica, and L. monocytogenes in pickling brines with a variety of acetic and benzoic acid combinations at pH 3.5 and 3.8. Evaluation of 15 different acid-pH combinations confirmed that strains of E. coli O157:H7 were significantly more acid resistant than strains of S. enterica and L. monocytogenes. Among the acid conditions tested, holding times of 4 days or less could achieve a 5-log reduction for vegetative pathogens at pH 3.5 with 2.5% acetic acid or at pH 3.8 with 2.5% acetic acid containing 0.1% benzoic acid. These data indicate the efficacy of benzoic acid for reducing the time necessary to achieve a 5-log reduction in target pathogens and may be useful for supporting process filings and the determination of critical controls for the manufacture of acidified foods. PMID:23834800

  19. Temporal changes in purity and specific activity of tritium-labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin: Radiopurity model for toxicology

    SciTech Connect

    Fernandez, J.D.; Cook, P.M.; Butterworth, B.C.; Bradbury, S.P.

    1999-10-15

    The specific activity (S) and radiopurity (R) of tritium labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin, [{sub 3}H]TCDD, were measured by gas chromatography/mass spectrometry (GC/MS) while attempting to accurately characterized TCDD doses received by invertebrates, fish, and fish embryos during several toxicology studies conducted over a 3 year period. The [{sub 3}H]TCDD sample was found to consist of six TCDD analogues involving hydrogen, deuterium, and tritium substitution at the 1,6-dibenzo-p-dioxin carbon positions and a complex mixture of impurities (with and without tritium labels). Planar aromatic impurities were identified a tolyl-TCDD adducts and appeared to result from the decay of {sub 3}H radiolabels to produce TCDD carbocations which reacted with the solvent, toluene. Formation of TriCDD and tolyl-TriCDDs, from both TCDD and tolyl-TCDDs, probably resulted from radiolysis-induced loss of a chlorine to form TriCDD free radicals which reacted with toluene. The measurement of S for [{sub 3}H]TCDD by GC/MS was accurate and precise ({+-}3%) because relative, rather than absolute, amounts of the analogues were determined. Changes in S over time were accurately modeled as a function of the conversion of each [{sub 3}H]TCDD analogue to a solvent-TCDD analogue at a rate determined by {sub 3}H loss due to decay. Storage, purification, and use of tritiated chemicals for toxicology studies requires consideration of the {sub 3}H decay-related phenomena. For example, hydroxylated TCDD is an expected decay reaction product of [{sub 3}H]TCDD in tissues and may be misidentified as a metabolite.

  20. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO2(+), CF3(+), N2O(+), C7H8(+), C7H7(+), C6H6(+), C6H5(+), C5H6(+), C4H4(+), and C3H3(+).

    PubMed

    Fournier, Joseph A; Shuman, Nicholas S; Melko, Joshua J; Ard, Shaun G; Viggiano, Albert A

    2013-04-21

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low (~10(11) cm(-3)) concentrations of a neutral precursor are added to a noble gas∕electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 10(9) and 10(10) cm(-3). Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cation yields the rate constant for DR. The technique is applied to several species (O2(+), CO2(+), CF3(+), N2O(+)) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of CnHm(+) (C7H7(+), C7H8(+), C5H6(+), C4H4(+), C6H5(+), C3H3(+), and C6H6(+)) derived from benzene and toluene neutral precursors. CnHm(+) DR rate constants vary from 8-12 × 10(-7) cm(3) s(-1) at 300 K with temperature dependences of approximately T(-0.7). Where prior measurements exist these results are in agreement, with the exception of C3H3(+) where the present results disagree with a previously reported flat temperature dependence. PMID:23614415

  1. Effects of structure on binding to the 2,3,7,8-TCDD receptor protein and AHH induction--halogenated biphenyls.

    PubMed Central

    Safe, S; Bandiera, S; Sawyer, T; Zmudzka, B; Mason, G; Romkes, M; Denomme, M A; Sparling, J; Okey, A B; Fujita, T

    1985-01-01

    The quantitative structure-activity relationships (QSARs) for polychlorinated biphenyl (PCB) congeners have been determined by comparing the EC50 values for three in vitro test systems, namely, aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) induction in rat hepatoma H-4-II-E cells and competitive binding avidities to the rat cytosolic receptor protein (using 2,3,7,8-tetrachlorodibenzo-p-dioxin as a radioligand). For several PCB congeners that are in vivo inducers of rat hepatic microsomal AHH, there was a linear correlation between the -log EC50 values for receptor and the -log EC50 values for AHH (or EROD) induction; moreover, a comparable linear relationship was observed between the -log EC50 values for AHH and EROD induction. Previous in vivo studies have shown that the most active PCB congeners 3,3',4,4'-tetra-, 3,4,4',5-tetra-, 3,3',4,4',5-penta-, and 3,3',4,4',5,5'-hexachlorobiphenyl, cause many of the biologic and toxic effects reported for the highly toxic halogenated aryl hydrocarbon, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Moreover, the monoortho-substituted homologs of the four coplanar PCBs also elicit comparable in vivo biologic and toxic responses. It was evident from the QSARs for PCBs that there was an excellent correspondence between the in vivo and in vitro potencies of the individual PCB congeners. The effects of substituents on both receptor binding and AHH/EROD induction was determined for a series of 4'-substituted (X)-2,3,4,5-tetrachlorobiphenyls (where X = H, Cl, Br, I, OH, OCH3, NO2, COCH3, F, CF3, CH3, C2H5, i-C3H7, n-C4H9 and t-C4H9). Not unexpectedly, there was a linear relationship between the -log EC50 values for AHH and EROD induction, and these results confirm that both enzymatic oxidations are catalyzed by the same cytochrome P-450 isozyme(s). The effects of substituent structure on receptor binding for 12 substituents was subjected to multiple regression analysis which correlates the relative binding

  2. 2,3,7,8-tetrachlorodibenzo-p-dioxin: examination of biochemical effects involved in the proliferation and differentiation of XB cells

    SciTech Connect

    Knutson, J.C.; Poland, A.

    1984-10-01

    XB, a cell line derived form a mouse teratoma, differentiates into stratified squamous epithelium when incubated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). To examine the mediators of this response the effects produced by TCDD and those elicited by other compounds which stimulated epidermal proliferation and/or differentiation in mice were compared, XB/3T3 cultures keratinize when incubated with cholera toxin, epidermal growth factor (EGF), or TCDD , but not 12-0-tetradecanoylphorbol-13-acetate (TPA). Incubation of XB cells with TCDD for 48 hours produces an increase in thymidine incorporation, a response which is neither as large nor as rapid as that produced by cholera toxin, TPA, or EGF. Although both cholera toxin and TCDD stimulate differentiation and thymidine incorporation in XB/3T3 cultures, cholera toxin increases cAMP 30-fold in these cells, while TCDD does not affect cAMP accumulation. Inhibitors of arachidonic acid metabolism, which block epidermal proliferative responses to TPA in vivo, do not prevent the differentiation of XB cells in response to TCDD. In XB/3T3 cultures, TPA stimulates arachidonic acid release at all times tested (1,6, and 24 hours) and increases the incorporation of /sup 32/P/sub i/ into total phospholipids and phosphatidyl-choline after 3 hours. In contrast, D affects neither arachidonic acid release nor the turnover of phosphatidylinositol, or phosphatidylcholine at any of the times tested. Although biochemical effects which have been suggested as part of the mechanism of TCDD and produced by other epidermal proliferative compounds in XB cells were examined, no mediator of the TCDD-produced differentiation of XB/3T3 cultures was observed.

  3. Ft-Ir Measurements of Cross Sections of Cold C_3H_8 in the 7 - 15 μm for Titan

    NASA Astrophysics Data System (ADS)

    Sung, Keeyoon; Toon, Geoffrey C.; Brown, Linda R.; Mantz, Arlan W.; Smith, Mary Ann H.

    2013-06-01

    To support atmospheric remote sensing of Titan, the absorption cross sections of N_2-broadened C_3H_8 were obtained at temperatures between 145 and 296 K. For this, 35 spectra of pure- and N_2-broadened propane were recorded in the 670 to 1900 cm-1 region using a Fourier transform spectrometer (Bruker IFS-125HR) at the Jet Propulsion Laboratory. A 20.38 cm path temperature-stabilized cryogenic absorption cell was used, which was developed at Connecticut College and described previously [1]. We report the absorption cross sections at the various cold temperatures for nine strong fundamental bands (ν_{26}, ν_8, ν_{21}, ν_{20}, ν_7, ν_{19}, ν_{18}, ν_4, ν_{24}) as well as for many contributions from hot and combination bands. In addition, we present results from 'pseudo -line generation' (http://mark4sun.jpl.nasa.gov/data/spec/Pseudo/Readme), which includes mean intensities and effective lower state energies on a 0.005 cm^{-1} frequency grid determined in the 690 - 1536 cm^{-1} region from all 35 high-resolution laboratory spectra. It was observed that the pseudo lines reproduce all the observed spectral transmittances well within 3% and the C_3H_8 amounts within 4% on the average. The measured cross sections and synthetic spectra from the pseudoline compilation are compared to earlier work, including the C_3H_8+N_2 spectra recorded at PNNL [2] and line-by-line predictions available [3, 4]. [1] K. Sung, A. W. Mantz, M. A. H. Smith, et al., J Mol Spectrosc 262, 122, 2010.; [2] S. W. Sharpe, et al., Appl Spectrosc 58, 1452, 2004.; [3] J. M. Flaud et al., Mol Phys 108, 699, 2010.; [4] J. M. Flaud et al., J Chem Phys 114, 9361, 2001. The research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology and at The College of William and Mary under contracts with National Aeronautics and Space Administration. US Government Support Acknowledged.

  4. Effect of vitamin B12 on cleft palate induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin and dexamethasone in mice.

    PubMed

    Zhao, Shu-Fan; Chai, Mao-Zhou; Wu, Min; He, Yong-Hong; Meng, Tian; Shi, Bing

    2014-03-01

    The purpose of this study was to investigate the effect of vitamin B12 on palatal development by co-administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dexamethasone (DEX). We examined the morphological and histological features of the palatal shelf and expression levels of key signaling molecules (transforming growth factor-β3 (TGF-β3) and TGF-β type I receptor (activin receptor-like kinase 5, ALK5)) during palatogenesis among a control group (Group A), TCDD+DEX exposed group (Group B), and TCDD+DEX+vitamin B12 exposed group (Group C). While we failed to find that vitamin B12 decreased the incidence of cleft palate induced by TCDD+DEX treatment, the expression levels of key signaling molecules (TGF-β3 and ALK5) during palatogenesis were significantly modulated. In TCDD+DEX exposed and TCDD+DEX+vitamin B12 exposed groups, palatal shelves could not contact in the midline due to their small sizes. Our results suggest that vitamin B12 may inhibit the expression of some cleft palate inducers such as TGF-β3 and ALK5 in DEX+TCDD exposed mice, which may be beneficial against palatogenesis to some degree, even though we were unable to observe a protective role of vitamin B12 in morphological and histological alterations of palatal shelves induced by DEX and TCDD.

  5. Major contributor to the large piezoelectric response in (1 - x)Ba(Zr0.2Ti0.8)O3 - x(Ba0.7Ca0.3)TiO3 ceramics: Domain wall motion

    NASA Astrophysics Data System (ADS)

    Gao, Jinghui; Hu, Xinghao; Zhang, Le; Li, Fei; Zhang, Lixue; Wang, Yu; Hao, Yanshuang; Zhong, Lisheng; Ren, Xiaobing

    2014-06-01

    The piezoelectric activity of lead-free Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 (BZT-xBCT) ceramics has been investigated as a function of composition by using Rayleigh analysis under subswitching-electric-field in combination with large-electric-field strain measurement. The result shows that the intrinsic piezoelectric response exhibits peak values in the vicinity of composition-induced R (rhombohedral)-MPB (morphotropic phase boundary) and MPB-T (tetragonal) phase transitions, but being much less than total d33 value. On the other hand, the extrinsic piezoelectric response, especially the one associated with reversible domain wall motion, has been greatly enhanced in the phase instability regime. Our results indicate that the extrinsic piezoelectric activity is the major contributor to the high piezoelectricity in BZT-xBCT ceramics.

  6. The atomic structure of lead-free Ba(Zr0.2Ti0.8)O3-(Ba0.7Ca0.3)TiO3 by using neutron total scattering analysis

    NASA Astrophysics Data System (ADS)

    Jeong, I.-K.; Ahn, J. S.

    2012-12-01

    We conducted neutron total scattering measurements on lead-free Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-0.5BCT) ceramic at 300 K and 150 K, and studied both long-range and local structures near the morphotropic phase boundary. Despite the long-range phase transition from tetragonal to rhombohedral structures, we found that local atomic structure of BZT-0.5BCT barely changes between 300 K and 150 K. To incorporate both long-range and local structures in a consistent way, we performed reverse Monte Carlo modeling. In BZT-0.5BCT, we found that the Ca substitution on Ba sites causes little impact on the local displacement of Ti ion but enhances octahedral tilting of ZrO6, resulting in nonuniform lattice distortion.

  7. Phase transitions and phase diagram of Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 Pb-free system by anelastic measurement

    NASA Astrophysics Data System (ADS)

    Xue, Dezhen; Gao, Jinghui; Zhou, Yumei; Ding, Xiangdong; Sun, Jun; Lookman, Turab; Ren, Xiaobing

    2015-03-01

    The internal friction and storage modulus of Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 (BZT-xBCT) Pb-free ceramics have been measured by dynamic mechanical analysis. The anelastic properties show clear anomalies with regard to the transformations between cubic (C), tetragonal (T), orthorhombic (O), and rhombohedral (R) phases, which are all of ferroelastic in nature. The previous reported T-R transition region in the BZT-xBCT system can be divided into the T-O and O-R transitions, consistent with recent studies on the appearance of an intermediate O phase. Based on the internal friction and storage modulus results, a revisited version of BZT-xBCT phase diagram is proposed.

  8. Oxygen desorption from YBa2Cu3O(7-x) and Bi2CaSr2Cu2O(8 + delta) superconductors

    NASA Technical Reports Server (NTRS)

    Mesarwi, A.; Levenson, L. L.; Ignatiev, A.

    1991-01-01

    Oxygen desorption experiments from YBa2Cu3O(7-x) (YBCO) and Bi2CaSr2Cu2O(8 + delta) (BSCCO) superconductors were carried out using a quadrupole mass spectrometer for monitoring the desorbing species and X-ray photoemission spectroscopy for surface characterization. Molecular oxygen was found to desorb from both superconductors following photoirradiation with ultraviolet/optical radiation and subsequent heating at over 150 C. Both YBCO and BSCCO were found to have similar oxygen desorption rates and similar activation energies. The desorption data as well as the X-ray photoemission data indicate that the oxygen desorption is not intrinsic to the superconductors but rather due to molecular oxygen entrapped in the material.

  9. Enthalpy Effect of Adding Cobalt to Liquid Sn-3.8Ag-0.7Cu Lead-Free Solder Alloy: Difference between Bulk and Nanosized Cobalt

    PubMed Central

    2016-01-01

    Heat effects for the addition of Co in bulk and nanosized forms into the liquid Sn-3.8Ag-0.7Cu alloy were studied using drop calorimetry at four temperatures between 673 and 1173 K. Significant differences in the heat effects between nano and bulk Co additions were observed. The considerably more exothermic values of the measured enthalpy for nano Co additions are connected with the loss of the surface enthalpy of the nanoparticles due to the elimination of the surface of the nanoparticles upon their dissolution in the liquid alloy. This effect is shown to be independent of the calorimeter temperature (it depends only on the dropping temperature through the temperature dependence of the surface energy of the nanoparticles). Integral and partial enthalpies of mixing for Co in the liquid SAC-alloy were evaluated from the experimental data. PMID:26877829

  10. Comparison of the inhibition of biliary excretion produced by certain inducing agents including 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Berman, E.F.; Schaus, P.; Fujimoto, J.M.

    1986-01-01

    Rats were treated with chlordecone, mirex, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and respective solvent vehicle. Under urethane or pentobarbital anesthesia, the bile duct was cannulated and radioactive morphine, imipramine, or ouabain was given by segmented retrograde intrabiliary injection. The spectrum of inhibition of biliary excretion by chlordecone and mirex were similar in that morphine glucuronide and in part polar imipramine metabolite recoveries in bile were decreased; ouabain recovery was unaffected. TCDD was different in that it markedly decreased the recovery of ouabain. Thus, it appears that chlordecone, mirex, and TCDD inhibit the canalicular transport of the glucuronide metabolites of morphine and imipramine into bile, and TCDD affects in addition the canalicular transport of ouabain into bile.

  11. Hopping and band mobilities of pentacene, rubrene, and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) from first principle calculations

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hajime; Kobayashi, Norihito; Hosoi, Shizuka; Koshitani, Naoki; Murakami, Daisuke; Shirasawa, Raku; Kudo, Yoshihiro; Hobara, Daisuke; Tokita, Yuichi; Itabashi, Masao

    2013-07-01

    Hopping and band mobilities of holes in organic semiconductors at room temperature were estimated from first principle calculations. Relaxation times of charge carriers were evaluated using the acoustic deformation potential model. It is found that van der Waals interactions play an important role in determining accurate relaxation times. The hopping mobilities of pentacene, rubrene, and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) in bulk single crystalline structures were found to be smaller than 4 cm2/Vs, whereas the band mobilities were estimated between 36 and 58 cm2/Vs, which are close to the maximum reported experimental values. This strongly suggests that band conductivity is dominant in these materials even at room temperature.

  12. Hopping and band mobilities of pentacene, rubrene, and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) from first principle calculations.

    PubMed

    Kobayashi, Hajime; Kobayashi, Norihito; Hosoi, Shizuka; Koshitani, Naoki; Murakami, Daisuke; Shirasawa, Raku; Kudo, Yoshihiro; Hobara, Daisuke; Tokita, Yuichi; Itabashi, Masao

    2013-07-01

    Hopping and band mobilities of holes in organic semiconductors at room temperature were estimated from first principle calculations. Relaxation times of charge carriers were evaluated using the acoustic deformation potential model. It is found that van der Waals interactions play an important role in determining accurate relaxation times. The hopping mobilities of pentacene, rubrene, and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) in bulk single crystalline structures were found to be smaller than 4 cm(2)∕Vs, whereas the band mobilities were estimated between 36 and 58 cm(2)∕Vs, which are close to the maximum reported experimental values. This strongly suggests that band conductivity is dominant in these materials even at room temperature. PMID:23822320

  13. We are Family: the Conformations of 1-FLUOROALKANES, C_nH2n+1F (n = 2,3,4,5,6,7,8)

    NASA Astrophysics Data System (ADS)

    Obenchain, Daniel A.; Orellana, W.; Cooke, S. A.

    2016-06-01

    he pure rotational spectra of the n = 5, 6, 7, and 8 members of the 1-fluoroalkane family have been recorded between 7 GHz and 14 GHz using chirped pulse Fourier transform microwave spectroscopy. The spectra have been analyzed and results will be presented and compared with previous work on the n= 2, 3, and 4 members. The lowest energy conformer for all family members has the common feature that the fluorine is in a gauche position relative to the alkyl tail for which all other heavy atom dihedral angles, where appropriate, are 180 degrees. For the n = 3 and higher family members the second lowest energy conformer has all heavy atom dihedral angles equal to 180 degrees. For each family member transitions carried by both low energy conformers were observed in the collected rotational spectra. Quantum chemical calculations were performed and trends in the energy separations between these two common conformers will be presented as a function of chain length. Furthermore, longer chain lengths have been examined using only quantum chemical calculations and results will be presented. M. Hayashi, M. Fujitake, T. Inagusa, S. Miyazaki, J.Mol.Struct., 216, 9-26, 1990 W. Caminati, A. C. Fantoni, F. Manescalchi, F. Scappini, Mol.Phys., 64, 1089 ,1988 L. B. Favero, A. Maris, A. Degli Esposti, P. G. Favero, W. Caminati, G. Pawelke, Chem.Eur.J., 6(16), 3018-3025, 2000

  14. 2,3,7,8-Tetrachlorodibenzo-p-dioxin specifically reduces mRNA for the mineralization-related dentin sialophosphoprotein in cultured mouse embryonic molar teeth

    SciTech Connect

    Kiukkonen, Anu . E-mail: Anu.Kiukkonen@helsinki.fi; Sahlberg, Carin; Lukinmaa, Pirjo-Liisa; Alaluusua, Satu; Peltonen, Eija; Partanen, Anna-Maija

    2006-11-01

    Previous studies show that the most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), interferes with mineralization of the dental matrices in developing mouse and rat teeth. Culture of mouse embryonic molar teeth with TCDD leads to the failure of enamel to be deposited and dentin to undergo mineralization. Lactationally exposed rats show defectively matured enamel and retardation of dentin mineralization. To see if the impaired mineralization is associated with changes in the expression of dentin sialophosphoprotein (Dspp), Bono1 and/or matrix metalloproteinase-20 (MMP-20), thought to be involved in mineralization of the dental hard tissues, we cultured mouse (NMRI) E18 mandibular molars for 3, 5 or 7 days and exposed them to 1 {mu}M TCDD after 2 days of culture. As detected by in situ hybridization of tissue sections, localization and intensity of Bono1 and MMP-20 expression showed no definite difference between the control and exposed tooth explants, suggesting that TCDD does not affect their expression. On the contrary, TCDD reduced or prevented the expression of Dspp in secretory odontoblasts and decreased it in presecretory ameloblasts. The results suggest that the retardation of dentin mineralization by TCDD in mouse molar teeth involves specific interference with Dspp expression.

  15. Development of bioassays and approaches for the risk assessment of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related compounds.

    PubMed Central

    Safe, S

    1993-01-01

    Polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and related halogenated aromatic hydrocarbons (HAHs) are industrial compounds or by-products that have been identified as contaminants in almost every component of the global ecosystem. 2,3,7,8- Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic HAH, and studies in rodents have shown that this compound is a carcinogen. Analysis of environmental samples for HAHs has shown that these extracts contain complex mixtures of isomers and congeners, and this greatly complicates risk assessment due to the paucity of data available for most of the individual compounds. Extensive research has demonstrated a common receptor-mediated mechanism of action for TCDD and related toxic HAHs, and this has led to the development of a mechanism-based risk assessment approach for HAHs. Toxic equivalency factors (TEFs; relative potency compared to TCDD) have been developed for selected HAH congeners, and the TEF values can be used to determine "toxic equivalents" (TEQs) for HAH mixtures. In addition, several bioassays that use receptor-mediated end points have been developed and can be used directly to determine the TEQs for HAH mixtures. The applications of the TEF/TEQ approach for the risk assessment of HAHs are considerable, particularly with the conversion of complex analytical data into TEQs. However, there appear to be several limitations to this approach, particularly with PCBs because their potential nonadditive (antagonistic), interactive effects with "2,3,7,8-TCDD-like" compounds may invalidate the use of the risk assessment procedure for some environmental matrices. PMID:8143638

  16. Evaluation of potential transmission of 2,3,7,8-tetrachlorodibenzo-p-dioxin-contaminated incinerator emissions to humans via foods

    SciTech Connect

    Fries, G.F.; Paustenbach, D.J. )

    1990-01-01

    Interest in the potential sources of human exposure to TCDD (dioxins, TCDD and equivalents, or 2,3,7,8-tetrachlorodibenzo-p-dioxin) via foods has recently shifted from phenoxy herbicides to products of combustion and waste disposal. Proposals to locate municipal waste combustors in rural areas have raised concerns that emissions, which could contain TCDD, could contaminate animal feeds and such human foods as milk, meat, and vegetables. Important factors that can affect the results of an assessment of incinerator emissions include (1) the emission and deposition rates of TCDD from the source, (2) the fractional retention and half-life of fly ash on plants, (3) the environmental half-life of TCDD, (4) the animal feeding and management systems, (5) the bioavailability of TCDD and related compounds, (6) the metabolism and pharmacokinetics of TCDD in farm animals, (7) food consumption levels, (8) the half-life of TCDD in humans, and (9) the model selected to estimate cancer risk. For persons living in the area of highest deposition near an incinerator, a possible uptake of TCDD from foods of animal origin was estimated to be about 10-40 fg/kg.d, which was much greater than the 1-5 fg/kg.d uptake estimated for foods of plant origin. The total uptake of TCDD from foods by the maximally exposed population will usually be about 500- to 1000-fold greater than that due to inhalation. Although milk was assumed to be the most important food pathway in several previous assessments that evaluated the hazards of airborne emissions, we determined that the deposition-forage-cattle-beef pathway was the more important route of exposure. The previous assessments appear to have used inappropriate pharmacokinetic models for TCDD and to have overestimated pasture use for dairy cows. 144 references.

  17. Coseismic deformation fields and a fault slip model for the Mw7.8 mainshock and Mw7.3 aftershock of the Gorkha-Nepal 2015 earthquake derived from Sentinel-1A SAR interferometry

    NASA Astrophysics Data System (ADS)

    Zuo, Ronghu; Qu, Chunyan; Shan, XinJian; Zhang, Guohong; Song, Xiaogang

    2016-08-01

    Coseismic deformation fields caused by the moment magnitude (Mw)7.8 mainshock and Mw7.3 aftershock of the 2015 Gorkha-Nepal earthquake are obtained by analyzing Sentinel-1A/IW ascending and descending interferometry data. Results show that the deformation field associated with the Mw7.8 mainshock roughly resembles a prolate ellipse, extending from the epicenter about 20° east by south. The main region of deformation is about 160 km by 110 km, comprising a large southern area of uplift, and a small northern area of subsidence. Assuming that rupture occurred in a homogeneous elastic half-space, the coseismic fault slip models of the mainshock and aftershock are inverted based on a shallow dip fault constrained by the three data sets, Sentinel-1A/IW descending data, ascending data, and ALOS-2 descending data, separately or in combination. Mainshock slip distributions generated from all three data sets are similar, and inversion constrained by all three in combination reveal a comprehensive fault slip model. Indeed, coseismic slip is mainly distributed within a narrow 40 km zone to the north of the Main Frontal Trust (MFT), and at 6-15 km subsurface depth. In addition, the maximum slip in this event was about 5.1 m, the Mw7.8 mainshock ruptured the deep part of the seismogenic zone, while the region between the southern boundary of the rupture area and the MFT remained locked. Therefore, a considerable earthquake risk remains to the south of Kathmandu. The inverted coseismic slip of the Mw7.3 aftershock was concentrated in a small area, close to, and southeast of the epicenter, with maximum displacement of about 3 m. Finally, because there is no overlap between the two slip areas of the mainshock and aftershock, the gap between them, about 15 km in length, has additional potential to generate future earthquakes.

  18. Comparison of the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on chemically impacted and nonimpacted subpopulations of Fundulus heteroclitus. 1: TCDD toxicity

    SciTech Connect

    Prince, R.; Cooper, K.R.

    1995-04-01

    A subpopulation of Fundulus heteroclitus inhabiting the chemically impacted estuary of Newark Bay, New Jersey, was found to be resistant to the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as compared to a chemically non-impacted subpopulation of F. heteroclitus in Tuckerton, New Jersey. The Newark/Raritan Bay estuary is a major site of TCDD contamination. The Newark F. heteroclitus embryos, when exposed to 12 to 100 parts per trillion (pptr) [{sup 3}H]TCDD/acetone (nominal water concentrations) did not exhibit TCDD-dependent lesions or death. In contrast, the Tuckerton embryos exhibited both TCDD concentration-related lesions and death that was associated with the lesions. The Newark embryonic resistance to TCDD toxicity could not be attributed to a lesser absorption of [{sup 3}H]TCDD as compared to the Tuckerton embryos. The Newark F. heteroclitus adult fish, when dermally treated with 0.30 to 60 ng/g [{sup 3}H]TCDD/DMSO, did not exhibit TCDD treatment-related increases in death, lesions, or liver-to-body-weight ratios, whereas the Tuckerton adult fish did. The Newark fish did exhibit greater parasitic infestations of the liver, greater hepatic neoplasias, and greater liver-to-body-weight ratios, all of which were independent of laboratory TCDD treatment, as compared to the Tuckerton fish. These hepatic effects in the Newark fish may be indicative of the chronic chemical exposure of this F. heteroclitus subpopulation.

  19. Effects of embryonic and adult exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin on hepatic microsomal testosterone hydroxylase activities in great blue herons (Ardea herodias)

    SciTech Connect

    Sanderson, J.T.; Giesy, J.P.; Janz, D.M.; Bellward, G.D.

    1997-06-01

    In a continuing effort to evaluate biomarkers of exposure of great blue herons (Ardea herodias) to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related halogenated aromatic hydrocarbons, the authors examined the effect of TCDD on hepatic microsomal testosterone hydroxylase activities. Heron embryos were exposed in ovo to 2 {micro}g TCDD/kg egg (or corn oil vehicle) and sacrificed at hatch or 7 d posthatch. Adult herons were exposed intraperitoneally to 20 {micro}g TCDD/kg and sacrificed 2 weeks later. The sex of the birds was known for the adults only. Hepatic microsomes of herons of each age group were able to hydroxylate testosterone at the 2{beta}, 6{beta}, 15{alpha}, 16{alpha}, or 16{beta} positions. In 7-d-old chicks, an additional unidentified compound was formed. The age of the untreated herons had a strong influence on the activities of the five hydroxylases, with changes of up to 17-fold. The TCDD significantly induced 2{beta}-, 6{beta}, and 15{alpha}-testosterone hydroxylase activities in the adult females, 15{alpha} in the adult males, and 6{beta}-testosterone hydroxylase activity in the hatchlings. In the 7-d-old chicks, induction was no longer apparent. A significant correlation existed between hepatic microsomal ethoxyresorufin O-deethylase (EROD) and 6{beta}-testosterone hydroxylase activity in hatchlings and adult female herons. The TCDD-induced changes in testosterone hydroxylase activities occurred at doses that resulted in tissue concentrations and levels of EROD induction that were environmentally relevant, but did not result in overt toxicities.

  20. Developmental Exposure To 2,3,7,8 Tetrachlorodibenzo-p-Dioxin Attenuates Later-Life Notch1-Mediated T Cell Development and Leukemogenesis

    PubMed Central

    Ahrenhoerster, Lori S.; Leuthner, Tess C.; Tate, Everett R.; Lakatos, Peter A.; Laiosa, Michael D.

    2015-01-01

    Over half of T-cell acute lymphoblastic leukemia (T-ALL) patients have activating mutations in the Notch gene. Moreover, the contaminant 2,3,7,8 Tetrachlorodibenzo-p-dioxin (TCDD) is a known carcinogen that mediates its toxicity through the aryl hydrocarbon receptor (AHR), and crosstalk between activated AHR and Notch signaling pathways has previously been observed. Given the importance of Notch signaling in thymocyte development and T-ALL disease progression, we hypothesized that the activated AHR potentiates disease initiation and progression in an in vivo model of Notch1-induced thymoma. This hypothesis was tested utilizing adult and developmental exposure paradigms to TCDD in mice expressing a constitutively active Notch1 transgene (NotchICN-TG). Following exposure of adult NotchICN-TG mice to a single high dose of TCDD, we observed a significant increase in the efficiency of CD8 thymocyte generation. We next exposed pregnant mice to 3μg/kg of TCDD throughout gestation and lactation to elucidate effects of developmental AHR activation on later-life T cell development and T-ALL-like thymoma susceptibility induced by Notch1. We found that the vehicle-exposed NotchICN-TG offspring have a peripheral T-cell pool heavily biased toward the CD4 lineage, while TCDD-exposed NotchICN-TG offspring were biased toward the CD8 lineage. Furthermore, while the vehicle-exposed NotchICN-TG mice showed increased splenomegaly and B to T cell ratios indicative of disease, mice developmentally exposed to TCDD were largely protected from disease. These studies support a model where developmental AHR activation attenuates later-life Notch1-dependent impacts on thymocyte development and disease progression. PMID:25585350

  1. Fungal oxidation of benzo(a)pyrene and (+-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene

    SciTech Connect

    Cerniglia, C.E.; Gibson, D.T.

    1980-06-10

    The oxidation of benzo(a)pyrene by intact cells of the filamentous fungus Cunninghamella elegans resulted in the formation of a complex mixture of polar products which were detected by high pressure liquid chromatography. One of the products had a retention time on high pressure liquid chromatography identical with that given by (+-)-7..beta..,8a,9a,10..beta..-tetrahydroxy-7,8,9,10-tetrahydrobenzo(a)pyrene. In addition the absorption and mass spectra given by the fungal metabolite were consistent with this structural assignment. Incubation of (+-)-trans-7,8-dihydrobenzo(a)pyrene with cells of C. elegans led to the formation of the same tetrahydroxymetabolite. Two other products were formed that were identified as new phenolic derivatives of (+-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene. Experiments with (+-)-trans (G-/sup 3/H) 7,8-dihydrobenzo(a)pyrene showed that over a 12-h period 4.0% of the dihydrodiol was converted to ethyl acetate-soluble products and 7..beta..,8..cap alpha..,9..cap alpha..,10..beta..-tetrahydroxy-7,8,9,10-tetrahdrobenzo(a)pyrene accounted for 25% of these metabolites. The results suggest that C. elegans can oxidize benzo(a)pyrene to either (+-)-7..beta..,8..cap alpha..-dihydroxy-9..cap alpha..,10..cap alpha..-epoxy-7,8,9,10-tetrahydroxy(a)pyrene or one of the two possible enantiomers of this compound. Under the experimental conditions, no evidence was found to suggest the formation of (+-)-7..beta..,8..cap alpha..-dihydroxy-9..beta..,10..beta..-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene. Thus, C. elegans has the ability to form at least one of the two diastereomeric benzo(a)pyrene 7,8-diol-9,10-epoxides that have been implicated as the ultimate carcinogenic forms of benzo(a)pyrene in higher organisms.

  2. Identification of Reference Proteins for Western Blot Analyses in Mouse Model Systems of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (TCDD) Toxicity

    PubMed Central

    Prokopec, Stephenie D.; Watson, John D.; Pohjanvirta, Raimo; Boutros, Paul C.

    2014-01-01

    Western blotting is a well-established, inexpensive and accurate way of measuring protein content. Because of technical variation between wells, normalization is required for valid interpretation of results across multiple samples. Typically this involves the use of one or more endogenous controls to adjust the measured levels of experimental molecules. Although some endogenous controls are widely used, validation is required for each experimental system. This is critical when studying transcriptional-modulators, such as toxicants like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).To address this issue, we examined hepatic tissue from 192 mice representing 47 unique combinations of strain, sex, Ahr-genotype, TCDD dose and treatment time. We examined 7 candidate reference proteins in each animal and assessed consistency of protein abundance through: 1) TCDD-induced fold-difference in protein content from basal levels, 2) inter- and intra- animal stability, and 3) the ability of each candidate to reduce instability of the other candidates. Univariate analyses identified HPRT as the most stable protein. Multivariate analysis indicated that stability generally increased with the number of proteins used, but gains from using >3 proteins were small. Lastly, by comparing these new data to our previous studies of mRNA controls on the same animals, we were able to show that the ideal mRNA and protein control-genes are distinct, and use of only 2–3 proteins provides strong stability, unlike in mRNA studies in the same cohort, where larger control-gene batteries were needed. PMID:25329058

  3. Gestational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin alters retinoid homeostasis in maternal and perinatal tissues of the Holtzman rat

    SciTech Connect

    Kransler, Kevin M. Tonucci, David A. McGarrigle, Barbara P. Napoli, Joseph L. Olson, James R.

    2007-10-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), one of the most widely studied environmental contaminants, causes a variety of adverse health effects including teratogenesis and altered development which may be related to disruptions in retinoid homeostasis. The purpose of this study was to determine the effect that gestational administration of TCDD has on retinoid homeostasis in both pregnant Holtzman rats and developing fetuses and neonates. A single oral dose of TCDD (0, 1.5, 3, or 6 {mu}g/kg) was administered to pregnant rats on gestation day 10, with fetuses analyzed on gestation days 17 and 20, and neonates analyzed on post natal day 7. Exposure to TCDD generally produced decreases in the concentrations of retinyl esters, such as retinyl palmitate, and retinol in maternal and perinatal liver and lung, while increasing levels in the maternal kidney. Additionally, perinatal hepatic retinol binding protein 1-dependent retinyl ester hydrolysis was also decrease by TCDD. Sensitivity of the developing perinates to TCDD appeared to have an age-related component demonstrated by an increased rate of mortality and significant alterations to body weight and length on post natal day 7 relative to that observed at gestation day 20. A unique observation made in this study was a significant decrease in lung weight observed in the perinates exposed to TCDD. Taken together, these data demonstrate that TCDD significantly alters retinoid homeostasis in tissues of the developing fetus and neonate, suggesting that their unique sensitivity to TCDD may at least be in part the result of altered retinoid homeostasis.

  4. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  5. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  6. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  7. 7 CFR 58.8 - How to make application.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false How to make application. 58.8 Section 58.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Grading Service § 58.8 How to make application. (a) On a fee basis. An application for inspection...

  8. 7 CFR 58.8 - How to make application.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false How to make application. 58.8 Section 58.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Grading Service § 58.8 How to make application. (a) On a fee basis. An application for inspection...

  9. 7 CFR 58.8 - How to make application.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false How to make application. 58.8 Section 58.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Grading Service § 58.8 How to make application. (a) On a fee basis. An application for inspection...

  10. 7 CFR 58.8 - How to make application.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false How to make application. 58.8 Section 58.8 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Grading Service § 58.8 How to make application. (a) On a fee basis. An application for inspection...

  11. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  12. 7 CFR 160.8 - Steam distilled wood turpentine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled wood turpentine” shall refer to the kind of spirits of turpentine obtained by steam distillation...

  13. Efficient Catalyst One-Pot Synthesis of 7-(Aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione Derivatives Complemented by Antibacterial Activity

    PubMed Central

    Al-Majedy, Yasameen K.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

    2016-01-01

    The problem of bacteria resistance to many known agents has inspired scientists and researchers to discover novel efficient antibacterial drugs. Three rapid, clean, and highly efficient methods were developed for one-pot synthesis of 7-(aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives. Three components are condensed in the synthesis, 4-hydroxycoumarin, 5,5-dimethyl-1,3-cyclohexanedione, and aromatic aldehydes, using tetrabutylammonium bromide (TBAB), diammonium hydrogen phosphate (DAHP), or ferric chloride (FeCl3), respectively. Each method has different reaction mechanisms according to the catalyst. The present methods have advantages, including one-pot synthesis, excellent yields, short reaction times, and easy isolation of product. All catalysts utilized in our study could be reused several times without losing their catalytic efficiency. All synthesized compounds were fully characterized and evaluated for their antibacterial activity. PMID:27563671

  14. Efficient Catalyst One-Pot Synthesis of 7-(Aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione Derivatives Complemented by Antibacterial Activity.

    PubMed

    Al-Majedy, Yasameen K; Al-Amiery, Ahmed A; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

    2016-01-01

    The problem of bacteria resistance to many known agents has inspired scientists and researchers to discover novel efficient antibacterial drugs. Three rapid, clean, and highly efficient methods were developed for one-pot synthesis of 7-(aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives. Three components are condensed in the synthesis, 4-hydroxycoumarin, 5,5-dimethyl-1,3-cyclohexanedione, and aromatic aldehydes, using tetrabutylammonium bromide (TBAB), diammonium hydrogen phosphate (DAHP), or ferric chloride (FeCl3), respectively. Each method has different reaction mechanisms according to the catalyst. The present methods have advantages, including one-pot synthesis, excellent yields, short reaction times, and easy isolation of product. All catalysts utilized in our study could be reused several times without losing their catalytic efficiency. All synthesized compounds were fully characterized and evaluated for their antibacterial activity. PMID:27563671

  15. (4R,7S)-2-Amino-4-(3,4-dimeth­oxy­phen­yl)-5-oxo-7-phenyl-5,6,7,8-tetra­hydro-4H-chromene-3-carbonitrile monohydrate

    PubMed Central

    Sun, Rong; Wu, Dong-Dong; Wang, Ke; Huang, Wei; Ou, Yang-Bing

    2012-01-01

    The title compound, C24H22N2O4·H2O, was obtained by the reaction of 3,4-dimeth­oxy­benzaldehyde, malononitrile and 5-phenyl­cyclo­hexane-1,3-dione. The cyclo­hexyl and pyran rings show half-boat and V-shaped conformations, respectively. The dihedral angle between the phenyl and benzene ring planes is 30.67 (9)°. The organic mol­ecules are packed in a two-dimensional network parallel to the bc plane stabilized by inter­molecular N—H⋯N and N—H⋯O hydrogen bonds. PMID:22347026

  16. Molecular metals based on 1,2,7,8-tetrahydrodicyclopenta[cd:lm]perylene and iodine, (CPP){sub 2}(I{sub 3}){sub 1-{delta}}

    SciTech Connect

    Morgado, J. |; Santos, I.C.; Henriques, R.T.; Almeida, M.; Fourmigue, M.; Matias, P.; Veiros, L.F.; Duarte, M.T.; Alcacer, L.; Calhorda, M.J. |

    1994-12-01

    The synthesis and characterization of molecular metals derived from 1,2,7,8-tetrahydrodicyclopenta[cd:lm]perylene (CPP) by partial oxidation with iodine and with general formula (CPP){sub 2}(I{sub 3}){sub 1-{delta}}, {delta} = 0-0.13, are reported. Single crystals, obtained either by electrocrystallization or by diffusion-controlled iodine oxidation of CPP, present two types of morphologies, elongated diamond or thinner needle-shaped crystals, both with a monoclinic cell, space group P2{sub 1}/a, a = 4.3757(9), b = 19.3681(11), c = 10.0860(11) {angstrom}, {beta} = 98.050(8){degrees}, V = 846.4(2) {angstrom}{sup 3}, Z = 2. The structure of the diamond-shaped crystal was solved by X-ray diffraction to a final R(F) = 0.096, R{sub w}(F) = 0.069. It consists of regular stacks of CPP molecules along a with a 3.41 {angstrom} spacing and uncorrected one-dimensional chains of I{sub 3}{sup {minus}} located in channels between four CPP stacks corresponding to (CPP){sub 2}(I{sub 3}){sub 0.892}. The thin needle crystals have the same unit cell but an unspecified and slightly different iodine content. Band structure calculations in this structure by the extended Hueckel method indicate a one-dimensional conduction band 0.55 eV wide. These thin needle crystals present, at room temperature, an electrical conductivity along the a axis {alpha}{sub a}(RT) = 200 S/cm and thermopower S{sub a}(RT) = 30 {mu}V/K, while for the diamond-shaped crystals {alpha}{sub a}(RT) = 2 S/cm and S{sub a}(RT) = -8 {mu}V/K. These transport coefficients for both types of crystals indicate a metallic behavior from room temperature down to {approx_equal}63 K, where a metal-to-insular (M-I) transition takes place. EPR studies in single crystals show an almost isotropic line at g = 2.0044 and with a width of {approx_equal}6 G in the range 80-300 K and without significant differences between the two types of crystals. 53 refs., 9 figs., 4 tabs.

  17. 7 CFR 29.3111 - Rule 8.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Rule 8. 29.3111 Section 29.3111 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... shall be considered. Minor irregularities which do not affect over one percent of the tobacco shall...

  18. Mathematics 7-8 Handbook, 1976 Reprint.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of General Education Curriculum Development.

    This handbook, prepared for teachers of grades 7 and 8, provides suggestions for teaching various aspects of the mathematics courses outlined in the syllabus of the New York State Education Department. The handbook deals with twelve units: sets, systems of numeration, natural numbers, whole numbers, positive rationals, integers, the complete set…

  19. 7 CFR 371.8 - International Services.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Organization of the United Nations, with regard to APHIS activities in foreign countries. (5) Developing and... their effect on the agriculture industry. (6) Developing and directing programs to enhance the trade in... 7 Agriculture 5 2014-01-01 2014-01-01 false International Services. 371.8 Section...

  20. 7 CFR 371.8 - International Services.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Organization of the United Nations, with regard to APHIS activities in foreign countries. (5) Developing and... their effect on the agriculture industry. (6) Developing and directing programs to enhance the trade in... 7 Agriculture 5 2013-01-01 2013-01-01 false International Services. 371.8 Section...

  1. 7 CFR 371.8 - International Services.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Organization of the United Nations, with regard to APHIS activities in foreign countries. (5) Developing and... their effect on the agriculture industry. (6) Developing and directing programs to enhance the trade in... 7 Agriculture 5 2012-01-01 2012-01-01 false International Services. 371.8 Section...

  2. 7 CFR 783.8 - Multiple benefits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... loans or payments resulting from purchase of the additional coverage insurance, as defined in 7 CFR 400... SPECIAL PROGRAMS TREE ASSISTANCE PROGRAM § 783.8 Multiple benefits. Persons may not receive or retain payments for production losses from trees, vines and bushes under this part if they have been...

  3. Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates later-life Notch1-mediated T cell development and leukemogenesis

    SciTech Connect

    Ahrenhoerster, Lori S.; Leuthner, Tess C.; Tate, Everett R.; Lakatos, Peter A.; Laiosa, Michael D.

    2015-03-01

    Over half of T cell acute lymphoblastic leukemia (T-ALL) patients have activating mutations in the Notch gene. Moreover, the contaminant 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) is a known carcinogen that mediates its toxicity through the aryl hydrocarbon receptor (AHR), and crosstalk between activated AHR and Notch signaling pathways has previously been observed. Given the importance of Notch signaling in thymocyte development and T-ALL disease progression, we hypothesized that the activated AHR potentiates disease initiation and progression in an in vivo model of Notch1-induced thymoma. This hypothesis was tested utilizing adult and developmental exposure paradigms to TCDD in mice expressing a constitutively active Notch1 transgene (Notch{sup ICN-TG}). Following exposure of adult Notch{sup ICN-TG} mice to a single high dose of TCDD, we observed a significant increase in the efficiency of CD8 thymocyte generation. We next exposed pregnant mice to 3 μg/kg of TCDD throughout gestation and lactation to elucidate effects of developmental AHR activation on later-life T cell development and T-ALL-like thymoma susceptibility induced by Notch1. We found that the vehicle-exposed Notch{sup ICN-TG} offspring have a peripheral T cell pool heavily biased toward the CD4 lineage, while TCDD-exposed Notch{sup ICN-TG} offspring were biased toward the CD8 lineage. Furthermore, while the vehicle-exposed NotchICN-TG mice showed increased splenomegaly and B to T cell ratios indicative of disease, mice developmentally exposed to TCDD were largely protected from disease. These studies support a model where developmental AHR activation attenuates later-life Notch1-dependent impacts on thymocyte development and disease progression. - Highlights: • Adult mice exposed to 30 μg/kg TCDD have higher efficiency of CD8 thymocyte generation. • Mice carrying a constitutively active Notch transgene were exposed to 3 μg/kg TCDD throughout development. • Progression of Notch

  4. Cardiac toxicity by sublethal 2,3,7,8-tetrachlorodibenzo-p-dioxin correlates with its anti-proliferation effect on cardiomyocytes in zebrafish embryos.

    PubMed

    Chen, Jing

    2015-02-01

    The cardiac toxicity of zebrafish embryos in response to the lethal dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been well characterized. Dioxin contamination levels in nature are usually lower, however, and sublethal TCDD toxicity is less investigated. The present study found that the nonlethal doses of TCDD for 72-h-postfertilization (hpf) zebrafish embryos were 25 pg/mL and lower. For the present study, sublethal TCDD concentrations of 10 pg/mL and 25 pg/mL were selected, and their toxicity was then characterized. The results showed that embryos still exhibited acute and subchronic cardiac toxicity at these 2 dosages. The stroke volume and cardiac output of these embryos significantly declined early until 8 d postexposure. Embryos' heart size became smaller, and the hearts contained fewer cardiomyocytes per heart, with decreased cardiomyocyte proliferation. Apoptosis was not detected either in the TCDD-treated or the control hearts. Real-time polymerase chain reaction (PCR) revealed that the transcription of a battery of cell-cycle-related genes was suppressed within the sublethal TCDD-treated heart. In contrast, embryonic jaw development seemed not to be affected. The present study suggests that dioxin contamination, even at lower levels, might lead to cardiac toxicity in fish embryos. Such cardiac toxicity presents as disrupted normal heart function, originating from the anti-proliferative effect of sublethal TCDD on cardiomyocytes.

  5. Bioaccumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin in feral fish collected from a bleach-kraft paper mill receiving stream

    SciTech Connect

    Schell, J.D. ); Campbell, D.M.; Lowe, E. )

    1993-11-01

    Bleach-kraft mill (BKM) processes may result in the formation and release of a number of chlorinated organic compounds, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Contamination of aquatic ecosystems by TCDD is of concern due to the chemical's toxicity, bioaccumulation potential, and persistence in the environment. Sediment samples and tissues from three species of fish an done invertebrate were collected downstream from a BKM facility and were analyzed for TCDD. Concentrations of TCDD were greatest in the bowfin, particularly in the ovary of a gravid female. There appeared to be no correlation between either trophic position of habitat classification (i.e., epibenthic or pelagic) and TCDD tissue concentrations. Sediments collected near the mill outfall contained elevated levels of TCDD as great as 52.8 ppt. Sediment-based BAFs and lipid- and carbon-normalized bioavailability indexes (BI) were calculated for the fish livers and gonads, and blue crab hepatopancreas. BAF*s varied by a factor of 27, depending on species and organ, whereas BIs had an approximate seven-fold variation. It appears that organic carbon- and lipid-normalization factors may be more accurate predictors of the extent of bioaccumulation in resident biota from TCDD-contaminated sediments than either BAF*s or BCFs. As there is currently only a limited understanding of species variability in absorption and deposition of TCDD, a more accurate estimation of TCDD levels in feral fish tissues may not be possible.

  6. Anti-Inflammatory Effect of 1,3,5,7-Tetrahydroxy-8-isoprenylxanthone Isolated from Twigs of Garcinia esculenta on Stimulated Macrophage

    PubMed Central

    Zhang, Dan-Dan; Zhang, Hong; Lao, Yuan-zhi; Wu, Rong; Xu, Jin-wen; Murad, Ferid; Bian, Ka; Xu, Hong-Xi

    2015-01-01

    Garcinia Linn. plants having rich natural xanthones and benzophenones with anti-inflammatory activity attracted a great deal of attention to discover and develop them as potential drug candidates. Through screening targeting nitric oxide accumulation in stimulated macrophage, we found that 1,3,5,7-tetrahydroxy-8-isoprenylxanthone (TIE) had potential anti-inflammatory effect. To understand how TIE elicits its anti-inflammatory activity, we uncovered that it significantly inhibits the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS/IFNγ-stimulated RAW264.7 cells. In further study, we showed that TIE reduced the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), two key molecules responsible for the production of NO and PGE2 during inflammation progress. Additionally, TIE also suppressed the expression of inflammatory cytokines IL-6, IL-12, and TNF-α. TIE-led suppression in iNOS, COX-2, and cytokines production were probably the consequence of TIE's capability to block ERK and p38MAPK signaling pathway. Moreover, TIE blocked activation of nuclear factor-kappa B (NF-κB) as well as NF-κB regulation of miR155 expression. Our study suggests that TIE may represent as a potential therapeutic agent for the treatment of inflammatory diseases. PMID:26538826

  7. Evaluation of chronic bronchitis, chronic obstructive pulmonary disease, and ventilatory function among workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect

    Calvert, G.M.; Sweeney, M.H.; Morris, J.A.; Fingerhut, M.A.; Hornung, R.W.; Halperin, W.E. )

    1991-12-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is produced as an undesirable contaminant in the manufacture of 2,4,5-trichlorophenol (TCP) and its derivatives. There is considerable concern about the health effects that may be associated with exposure to TCDD-contaminated substances. A cross-sectional medical study that included a comprehensive medical history, medical examination, and measurement of pulmonary function was conducted on workers employed more than 15 yr earlier in the manufacture of NaTCP and its derivatives at two chemical plants. The workers had substantial exposure to substances contaminated with TCDD, as evidenced by a mean serum TCDD level, lipid adjusted, of 200 ppt compared with a mean of 7 ppt in the unexposed reference group. The comparison group consisted of individuals with no occupational exposure to phenoxy herbicides who lived in the same communities as the workers. A total of 281 workers and 260 unexposed referents participated in the medical examination. Logistic and linear regression analyses, which contained categorical and continuous measures of TCDD exposure, were performed to control for important confounders, including cigarette and alcohol consumption. No difference was found between workers and referents in the risk for chronic bronchitis or COPD. Analysis of the ventilatory function data revealed no association between history of exposure to substances contaminated with TCDD and the forced expiratory volume at one second (FEV1), forced vital capacity (FVC), or the ratio of FEV1 to FVC (FEV1/FVC%).

  8. 2,3,7,8-Tetrachlorodibenzo-p-dioxin induces apoptotic cell death and cytochrome P4501A expression in developing Fundulus heteroclitus embryos

    USGS Publications Warehouse

    Toomey, B.H.; Bello, S.; Hahn, M.E.; Cantrell, S.; Wright, P.; Tillitt, D.E.; Di Giulio, R.T.

    2001-01-01

    Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC50 and LD50 of TCDD for Fundulus embryos were ???19.7??9.5 pg TCDD/??l (water bath) and 0.25??0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, eye, gill, kidney, tail, intestine, heart, and vascular tissue. CYP1A expression was also increased in the TCDD-exposed embryos predominantly in liver, kidney, gill, heart, intestine, and in vascular tissues throughout the embryo. There was co-occurrence of TCDD-induced apoptosis and CYP1A expression in some, but not all, cell types. In addition the dose response relationships for apoptosis and mortality were similar, while CYP1A expression appeared more sensitive to TCDD induction. Copyright ?? 2001 Elsevier Science B.V.

  9. Hypertension, Cardiac Hypertrophy, and Impaired Vascular Relaxation Induced by 2,3,7,8-Tetrachlorodibenzo-p-Dioxin are Associated with Increased Superoxide

    PubMed Central

    Kopf, Phillip G.; Huwe, Janice K.

    2009-01-01

    The mechanisms by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increases the incidence of human cardiovascular disease are not known. We investigated the degree to which cardiovascular disease develops in mice following subchronic TCDD exposure. Adult male C57BL/6 mice were dosed with vehicle or 300 ng TCDD/kg by oral gavage three times per week for 60 days. Blood pressure was recorded by radiotelemetry and aortic endothelial function was assessed by acetylcholine-induced vasorelaxation. Mean arterial pressure of TCDD-exposed mice was increased significantly by day 4 and between days 7–10, 25–35, and 45–60 with two periods of normalization on days 11–24 and days 36–39. Consistent with a prolonged period of systemic hypertension, heart weight was increased and was associated with concentric left ventricular hypertrophy. Significant increases in superoxide production also were observed in the kidney, heart, and aorta of TCDD-exposed mice. Furthermore, increased aortic superoxide resulted in endothelial dysfunction as demonstrated by significant impairment of acetylcholine-induced vasorelaxation in TCDD-exposed mice, which was restored by tempol, a superoxide dismutase (SOD) mimetic. Our model is the first to definitely demonstrate that sustained AhR activation by TCDD increases blood pressure and induces cardiac hypertrophy, which may be mediated, in part, by increased superoxide. PMID:18850075

  10. Impact of 2,3,7,8-TCDD exposure on survival, growth, and behavior of osprey`s breeding in Wisconsin, USA

    SciTech Connect

    Woodford, J.E.; Karasov, W.H.; Meyer, M.W.; Chambers, L.

    1998-07-01

    Osprey (Pandion halieatus) eggs collected from areas 7 km downstream from two bleached-kraft mill facilities from 1992 to 1996 contained much higher levels of 2,3,7,8-tetrachlordibenzo-p-dioxin than eggs collected from two reference areas upstream. Levels in eggs of the remaining planar halogenated hydrocarbon congeners and other nonplanar organochlorines were not statistically different between the contaminated and upstream areas. The authors placed eggs from the contaminated area into nests at both reference areas (group A) and eggs from the reference areas into nests at the contaminated area (group B). No significant differences in egg hatching or chick fledging rates were observed between these groups and nests left unmanipulated at both reference areas (group C) and the contaminated area (group D). Mass increase rates of chicks differed significantly, with the highest rates from group C and the lowest rates from group B. This difference cannot be easily attributed to differences in parental test attentiveness or food provisioning, which were greater at the contaminated area. The authors conclude that although current planar halogenated hydrocarbon exposure levels were not affecting hatching and fledging rates, they may have affected chick growth.

  11. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  12. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  13. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  14. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  15. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  16. Quantum chemical, ballistic and explosivity calculations on 2,4,6,8-tetranitro-1,3,5,7-tetraaza cyclooctatetraene: a new high energy molecule.

    PubMed

    Gejji, S P; Talawar, M B; Mukundan, T; Kurian, E M

    2006-06-30

    Ab initio molecular orbital calculations have been carried out on 2,4,6,8-tetranitro-1,3,5,7-tetraazacyclooctatetraene, the tetramer of the series (NO(2)CN)(n) where n=1-4, using the Hartree-Fock theory with the 6-31 G(d) basis set. These calculations yield three conformers for the tetramer with D(4h), C(4h) and C(2) symmetries. The nonplanar conformer with the C(2) symmetry turns out to be 99.0 and 164.4kJmol(-1), respectively, lower in energy than the C(4h) and D(4h) conformers. The electron density topography - the density at the bond critical point - has been used as a measure of the CNO(2) strengths. Based on these bond strengths, heats of formation [obtained from the parametric model 3 (PM3) method] and specific decomposition energies, it may be concluded that (NO(2)CN)(4) is a promising candidate in the class of high energy molecules. Theoretically computed explosive (velocity of detonation, detonation pressure, etc.) and ballistic (characteristic velocity, specific impulse, etc.) parameters support these conclusions.

  17. Global study of great (M>= 7) deep focus seismic events having regard to the May 24, 2013 Mw 8.3 earthquake the Sea of Okhotsk, Russia

    NASA Astrophysics Data System (ADS)

    Varga, Peter; Rogozhin, Evgeny; Süle, Bálint; Andreeva, Nadezda

    2014-05-01

    Distribution of great seismic events M >= 7.0 and consequently the released seismic energy along the Earth radius is of bimodal character. 90% of the great seismic events, which are responsible for the most of energy released, occur relatively close to the Earth's surface, at an average depth of 50 km. The vast majority of remaining 10% is associated with seismic events that occur very deep, an average of 580-590 km, above the border between transition zone and lower mantle (660 km). These very deep earthquakes (depth >= 500 km) differ significantly from the shallow events. For the study of the distribution of M >= 7.0 earthquakes and their radiated energy a catalogue was completed for the time-interval between 1900 and 2013. Examination of the source zones in which both shallow and deep M >= 7.0 earthquakes occur shows that linear distribution of deep earthquakes is considerably shorter than that found for the shallow earthquakes, which determine the length of the zone. The position of very deep (≥ 500 km) earthquakes foci show where the down going lithosperic plates conflict with the upper boundary of lower mantle, and where they probably cross it. This passage generates compression - elongation inside the slab. A comparison of temporal distribution of shallow and deep seismic events of a given source zone suggests that there is no direct relationship in the distribution of these two different earthquake activities. The largest of these great deep earthquakes, the May 24, 2013 Mw 8.3 earthquake the Sea of Okhotsk, was preceded by an earthquake swarm, which consists 58 M >= 5 events and occurred between May 15 and 24, 2013 in the higher part of the sinking slab east of Kamchatka. The aftershock activity after the Okhotsk Sea earthquake was moderate: twelve events with magnitudes above M 4 were observed till June 27. These events determine a fault area (2.64x104 km2) similar to the case of a shallow M 8.3 event. The effect of Okhotsk Sea was felt throughout

  18. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure of normal human dermal fibroblasts results in AhR-dependent and -independent changes in gene expression

    SciTech Connect

    Akintobi, A.M.; Villano, C.M.; White, L.A. . E-mail: lawhite@aesop.rutgers.edu

    2007-04-01

    Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) results in a variety of lesions in mammals including severe skin lesions. The majority of TCDD's biological effects are mediated through activation of the aryl hydrocarbon receptor (AhR). We have chosen to examine the effect of TCDD and the AhR pathway on dermal fibroblasts because this cell type plays an integral role in skin homeostasis through the production of cytokines and other factors that regulate epidermal proliferation and differentiation. Our data show that normal human dermal fibroblasts (NHDFs) are responsive to TCDD, as demonstrated by induction of cytochrome p450 1B1 (CYP1B1) expression. Further, our data demonstrate that TCDD treatment of NHDFs results in significant (75-90%) decrease in expression of Id-1 and Id-3, proteins that are involved in regulation of cell proliferation and differentiation. The Id (Inhibitor of DNA binding) proteins are transcriptional inhibitors that function by forming inactive heterodimers with other HLH proteins. TCDD-repression of Id-1 and -3 is independent of de novo protein synthesis; co-treatment with cycloheximide has no effect on TCDD inhibition of Id-1 and Id-3. Co-treatment with the AhR antagonist {alpha}-naphthoflavone also does not block inhibition of Id-1 and Id-3 by TCDD, suggesting that TCDD inhibition of Id-1 and Id-3 is, at least in part, mediated independently of the AhR pathway. Our data also show that TCDD inhibits expression of the cell cycle regulatory gene p16{sup ink4a}, which is often linked to Id expression. TCDD-induced reduction of p16{sup ink4a} expression is also independent of protein synthesis and the AhR pathway.

  19. Boron isotopes in tourmaline from the ca. 3.7-3.8 Ga Isua supracrustal belt, Greenland: Sources for boron in Eoarchean continental crust and seawater

    NASA Astrophysics Data System (ADS)

    Grew, Edward S.; Dymek, Robert F.; De Hoog, Jan C. M.; Harley, Simon L.; Boak, Jeremy; Hazen, Robert M.; Yates, Martin G.

    2015-08-01

    Boron is highly concentrated in Earth's crust relative to primitive mantle. However, when present-day crustal concentrations were achieved remains debatable. It has been proposed that seawater boron δ11B was lower than at present, consistent with a model relating increase in sea-water δ11B to the proportion of B extracted from Earth's mantle into the oceans and crust. Our in situ ion microprobe analyses of tourmaline in 17 samples from the Eoarchean Isua supracrustal belt, Southwest Greenland, gave the following average δ11B with uncertainties ranging from ±0.4 to ±1.9‰: δ11B = -7.1 to -11.5‰ in amphibolite; δ11B = -10.5 to -25.3‰ in mica schist; δ11B = -19.2‰ in metachert (one sample), and δ11B = -21.9‰ in metaconglomerate (one sample). Tourmaline is largely schorl-dravite, rarely uvite-feruvite, and shows color and compositional zoning. δ11B varies from grain to grain in most samples; grains in a kyanite-staurolite schist are isotopically zoned, possibly because the rims incorporated B released by muscovite breakdown. The patterns in color-zoned tourmaline grains in our samples are not consistent with detrital origin of the cores, which rules out the possibility of there being tourmaline detritus from pre-existing continental crust in the studied samples. The tourmaline-bearing rocks are found in both the ca. 3700 Ma northern and ca. 3800 Ma southern terranes in the Isua supracrustal belt. Following an approach suggested by Chaussidon and Appel, we estimated Eoarchean seawater δ11B by calculating back from δ11B of tourmaline in metasedimentary rocks using fractionation of boron isotopes between clays and muscovite, tourmaline and aqueous fluid. This calculation gave an estimated δ11B ≈ +14 ± 15‰ for Eoarchean seawater, 25‰ lower than present-day seawater (δ11B = +39.5‰). For comparison, an estimate obtained simply by direct comparison of δ11B for Eoarchean and Phanerozoic tourmaline presumed to have crystallized in similar

  20. Involvement of SREBPs in 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced disruption of lipid metabolism in male guinea pig

    SciTech Connect

    Nishiumi, Shin; Yabushita, Yoshiyuki; Furuyashiki, Takashi; Fukuda, Itsuko; Ashida, Hitoshi

    2008-06-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has multiple toxic effects causing a wasting syndrome characterized by a loss of body weight accompanied by a decrease in adipose tissue weight. To elucidate the mechanism behind this syndrome, we investigated the changes in lipid metabolism 7 and 21 days after a single intraperitoneal injection of TCDD at 1 {mu}g/kg body weight to male guinea pigs. TCDD caused the symptoms of the syndrome, body weight loss with a decrease in adipose tissue weight, while it increased the levels of triacylglycerols, total cholesterols, and free fatty acids in plasma. On day 7, TCDD decreased the levels of CCAAT/enhancer binding protein (C/EBP) {alpha}, peroxisome proliferator activated receptor {gamma}, and glucose transporter 4, adipogenesis-related factors, in adipose tissue, whereas the levels of retinoid X receptor {alpha}, C/EBP{beta}, C/EBP{delta}, and c-Myc remained unchanged. TCDD also reduced the levels of both p125 precursor and p68 active forms of sterol regulatory element binding protein (SREBP)-1 and -2, the lypogenesis-related factors, and downregulated their DNA binding activity in adipose tissue, while it raised the levels of their p68 active forms and increased their DNA binding activity in the liver. TCDD decreased mRNA and protein levels of acetyl-CoA carboxylase and HMG-CoA synthase in the liver and adipose tissue. Similar results were obtained on day 21. These results suggest that TCDD disrupts lipid metabolism through changes in the expression levels of the adipogenesis-related and lipogenesis-related proteins in the liver and adipose tissue, and SREBPs would be involved in the development of the wasting syndrome.

  1. RDamage 6, 7, 8 & 9 Cassettes

    SciTech Connect

    Griego, Jeffrey R; Kaul, Ann

    2012-06-08

    The RDamage series of ten experiments is part of a long-term collaboration with RFNC/VNIIEF in pulsed power technology. These experiments use a cylindrical configuration to study spallation damage, which allows for a natural recollection of the damaged material under proper driving conditions and post-shot collection of the damaged target material for subsequent metallographic analysis. Dynamic insitu experimental velocimetry diagnostics are also employed. LANL is responsible for the design of the experimental load and velocimetry system. VNIIEF is responsible for the design and construction of the driving explosive magnetic generator. In the RDamage-0, -1 and -2 experiments, data was collected about failure initiation of a well-characterized material (aluminum) in a cylindrical geometry. The RDamage-3, -4 and -5 experiments produced data on the behavior of material recollected after damage from pressures in the damage initiation regime. Data on the behavior of material recollected after complete failure was collected in the RDamage-6, -7, -8 and -9 experiments. This presentation shows the evolution of the load assembly through the experimental series.

  2. Differential toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in C57BL/6J mice congenic at the Ah Locus.

    PubMed

    Birnbaum, L S; McDonald, M M; Blair, P C; Clark, A M; Harris, M W

    1990-07-01

    The acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was examined in male C57BL/6J mice differing only at the Ah locus. Wild type mice (Ahb/b, "b/b") were treated once with 0, 50, 100, 200, 300, and 400 micrograms TCDD/kg po while congenic mice (Ahd/d, "d/d") received a single dose of 0, 400, 800, 1600, 2400, and 3200 micrograms TCDD/kg. Mice were checked daily, weighed twice a week, and those that survived, killed 35 days post-treatment. The LD50 values were 159 and 3351 micrograms/kg for b/b and d/d mice, respectively. Mean time to death was 22 days and was independent of dose and genotype. Decrease in body weight gain was noted in both strains 5 days after treatment and occurred at doses greater than or equal to 100 micrograms/kg in b/b mice and 1600 micrograms/kg in d/d mice. Dose-related increases in liver weight (both absolute and relative to body weight) and decreases in thymus, spleen, testes, and epididymal fat pad weights were observed at 8-24-fold higher doses in d/d than in b/b mice. A dose-related increase in segmented neutrophils was observed in both strains. Serum chemistry values indicated that 8-24X greater doses of TCDD were needed to elevate sorbitol dehydrogenase, alanine aminotransferase, and 5'-nucleotidase and to decrease total and esterified cholesterol in d/d than in b/b mice. Few effects were seen on total bile acids, serum triglycerides, glucose, or nonesterified cholesterol. In the liver, hepatocellular cytomegaly, fatty change, and bile duct hyperplasia occurred in both strains in a dose-related manner, as did thymic and splenic atrophy. Necrosis of germinal epithelium in the testes and edema in the stomach submucosa occurred at acutely toxic doses. These lesions also occurred at doses 8-24X greater in d/d than in b/b mice. Thus, the spectrum of toxicity is independent of the allele at the Ah locus, but the relative dose needed to bring about various acute responses is approximately 8-24X greater in congenic mice homozygous

  3. Synthesis, biological assessment, and molecular modeling of racemic 7-aryl-9,10,11,12-tetrahydro-7H-benzo[7,8]chromeno[2,3-b]quinolin-8-amines as potential drugs for the treatment of Alzheimer's disease.

    PubMed

    Maalej, Emna; Chabchoub, Fakher; Oset-Gasque, María Jesús; Esquivias-Pérez, Mario; González, María P; Monjas, Leticia; Pérez, Concepción; de los Ríos, Cristóbal; Rodríguez-Franco, María Isabel; Iriepa, Isabel; Moraleda, Ignacio; Chioua, Mourad; Romero, Alejandro; Marco-Contelles, José; Samadi, Abdelouahid

    2012-08-01

    The synthesis, pharmacological analysis and molecular modeling of the readily available racemic tacrine analogs 21-30, bearing the 7-aryl-9,10,11,12-tetrahydro-7H-benzo[7,8]chromeno[2,3-b]quinolin-8-amine heterocyclic ring system (II), prepared by Friedländer reaction of 2-amino-4-aryl-4H-benzo[h]chromene-3-carbonitriles (11-20) with cyclohexanone, are described in this paper. Molecules 21-30 are potent and selective inhibitors of hAChE, in the low micromolar range, one of the most potent inhibitors, 4-(8-amino-9,10,11,12-tetrahydro-7H-benzo[7,8]chromeno[2,3-b]quinolin-7-yl)-2-methoxyphenol (25), showing a IC(50) (hAChE) = 0.33 ± 0.04 μM. Kinetic studies of compound 25 proved that this compound is a mixed type inhibitor for EeAChE (K(i) = 81 nM). Accordingly, molecular modeling of inhibitor 25 showed that both enantiomers have two major predicted binding modes at the active and at the peripheral anionic sites of AChE. Inhibitor 25 has an excellent antioxidant profile as determined in the ORAC experiment (1.47 ± 0.10 Trolox equiv). Inhibitors 26-28 and 30 are permeable to BBB as determined in the PAMPA assay. Compared to tacrine, selected compounds 26-28 and 30 showed less hepatic toxicity in HepG2 cells. Moreover, cell viability-related studies in cortical neurons in primary cultures show that compounds 26-28 and 30 (0.1-50 μM) have significant neuroprotective effects against mitochondrial chain blockers-induced cell death, and, unlike tacrine, are not neurotoxic at concentrations lower than 50 μM. It is worth highlighting that compound 27 has the best neuroprotective properties out of all assayed compounds and shows no neurotoxicity. To sum up, these tacrine analogs can be considered as attractive multipotent therapeutic molecules on pharmacological receptors playing key roles in the progress of Alzheimer's disease. PMID:22795665

  4. Accumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin by rainbow trout (Onchorhynchus mykiss) at environmentally relevant dietary concentrations

    USGS Publications Warehouse

    Jones, Paul D.; Kannan, Kurunthachalam; Newsted, John L.; Tillitt, Donald E.; Williams, Lisa L.; Giesy, John P.

    2001-01-01

    Rainbow trout were fed a diet containing 1.8, 18, or 90 pg/g 3H-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for up to 320 d. Concentrations of TCDD were determined in muscle, liver, and ovaries at 100, 150, 200, and 250 d. Concentrations of TCDD reached an apparent steady-state concentration in liver after 100 d of exposure, whereas concentrations in other tissues continued to increase until 150 d of exposure. The greatest portion of the total mass of TCDD was present in the muscle tissue with lesser proportions in other organs. As the ovaries developed before spawning, an increase occurred in the total mass of TCDD present in this tissue. The assimilation rate of TCDD during the initial 100 d of the exposure was determined to be between 10 and 30%. This is somewhat less than estimates derived based on both uptake and elimination constants determined during shorter exposures. Biomagnification factors (BMFs) were estimated for all tissues and exposure concentrations, and at all exposure periods. Lipid-normalized BMFs for muscle ranged from 0.38 to 1.51, which is consistent with the value of 1.0 predicted from fugacity theory. Uptake and depuration rate constants were determined and used to predict individual organ TCDD concentrations. Comparison with observed values indicated that the model could be used to predict tissue concentrations from the known concentrations of TCDD in food. This model will allow more refined risk assessments by predicting TCDD concentrations in sensitive tissues such as developing eggs.

  5. Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates capacity of hematopoietic stem cells to undergo lymphocyte differentiation

    SciTech Connect

    Ahrenhoerster, Lori S.; Tate, Everett R.; Lakatos, Peter A.; Wang, Xuexia; Laiosa, Michael D.

    2014-06-01

    The process of hematopoiesis, characterized by long-term self-renewal and multi-potent lineage differentiation, has been shown to be regulated in part by the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous contaminant and the most potent AHR agonist, also modulates regulation of adult hematopoietic stem and progenitor cell (HSC/HPC) homeostasis. However, the effect of developmental TCDD exposure on early life hematopoiesis has not been fully explored. Given the inhibitory effects of TCDD on hematopoiesis and lymphocyte development, we hypothesized that in utero exposure to TCDD would alter the functional capacity of fetal HSC/HPCs to complete lymphocyte differentiation. To test this hypothesis, we employed a co-culture system designed to facilitate the maturation of progenitor cells to either B or T lymphocytes. Furthermore, we utilized an innovative limiting dilution assay to precisely quantify differences in lymphocyte differentiation between HSC/HPCs obtained from fetuses of dams exposed to 3 μg/kg TCDD or control. We found that the AHR is transcribed in yolk sac hematopoietic cells and is transcriptionally active as early as gestational day (GD) 7.5. Furthermore, the number of HSC/HPCs present in the fetal liver on GD 14.5 was significantly increased in fetuses whose mothers were exposed to TCDD throughout pregnancy. Despite this increase in HSC/HPC cell number, B and T lymphocyte differentiation is decreased by approximately 2.5 fold. These findings demonstrate that inappropriate developmental AHR activation in HSC/HPCs adversely impacts lymphocyte differentiation and may have consequences for lymphocyte development in the bone marrow and thymus later in life.

  6. A Single Gestational Exposure to 2,3,7,8-Tetrachlorodibenzo-p-dioxin Disrupts the Adult Uterine Response to Estradiol in Mice

    PubMed Central

    Korach, Kenneth S.

    2013-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) given as a cotreatment with estrogen exhibits antiestrogenic properties on the rodent adult uterus, but less is understood regarding hormonal responsiveness of the adult uterus from animals having been exposed to TCDD during critical periods of development. We characterized the inhibitory effects of TCDD (T) exposure at gestational day 15 (GD15), 4 weeks, and 9 weeks of age (TTT) on the adult uterus following hormone treatment. TTT-exposed mice in response to hormone treatment exhibited a blunted weight increase, had fewer uterine glands, displayed morphological anomalies, and had marked decreases in the hormonal regulation of genes involved in fluid transport (Aqp3 and Aqp5), cytoarchitectural (Dsc2 and Sprr2A), and immune (Lcn2 and Ltf) regulation. To determine if the 9-week exposure was responsible for the blunted uterine response, due to the 7- to 11-day half-life of TCDD in mice, a second set of experiments was performed to examine exposure to TCDD given at GD15, GD15 only (cross-fostered at birth), only during lactation (cross-fostered at birth), or at GD15 and 4 weeks of age. Our studies demonstrate that a single developmental TCDD exposure at GD15 is sufficient to elicit a blunted adult uterine response to estradiol and is due in part to fewer gland numbers and the reduced expression of forkhead box A2 (FoxA2), a gene involved in gland development. Together, these results provide insight regarding the critical nature of in utero exposure and the potential impact on ensuing uterine biology and reproductive health later in life. PMID:24052564

  7. Developmental Exposure to 2,3,7,8 Tetrachlorodibenzo-p-dioxin Attenuates Capacity of Hematopoietic Stem Cells to Undergo Lymphocyte Differentiation

    PubMed Central

    Ahrenhoerster, Lori S.; Tate, Everett R.; Lakatos, Peter A.; Wang, Xuexia; Laiosa, Michael D.

    2014-01-01

    The process of hematopoiesis, characterized by long-term self-renewal and multi-potent lineage differentiation, has been shown to be regulated in part by the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR). 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous contaminant and the most potent AHR agonist, also modulates regulation of adult hematopoietic stem and progenitor cell (HSC/HPC) homeostasis. However, the effect of developmental TCDD exposure on early life hematopoiesis has not been fully explored. Given the inhibitory effects of TCDD on hematopoiesis and lymphocyte development, we hypothesized that in utero exposure to TCDD would alter the functional capacity of fetal HSC/HPCs to complete lymphocyte differentiation. To test this hypothesis, we employed a co-culture system designed to facilitate the maturation of progenitor cells to either B or T lymphocytes. Furthermore, we utilized an innovative limiting dilution assay to precisely quantify differences in lymphocyte differentiation between HSC/HPCs obtained from fetuses of dams exposed to 3μg/kg TCDD or control. We found that the AHR is transcribed in yolk sac hematopoietic cells and is transcriptionally active as early as gestational day (GD) 7.5. Furthermore, the number of HSC/HPCs present in the fetal liver on GD 14.5 was significantly increased in fetuses whose mothers were exposed to TCDD throughout pregnancy. Despite this increase in HSC/HPC cell number, B and T lymphocyte differentiation is decreased by approximately 2.5 fold. These findings demonstrate that inappropriate developmental AHR activation in HSC/HPCs adversely impacts lymphocyte differentiation and may have consequences for lymphocyte development in the bone marrow and thymus later in life. PMID:24709672

  8. Effect of tocopherol on biochemical blood parameters in pleuritis-induced rats treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin.

    PubMed

    Całkosiński, Ireneusz; Rosińczuk-Tonderys, Joanna; Bronowicka-Szydełko, Agnieszka; Dzierzba, Katarzyna; Bazan, Justyna; Dobrzyński, Maciej; Majda, Jacek; Gamian, Andrzej

    2015-06-01

    The aim of this study was to evaluate the effect of tocopherol on pleuritis-induced rats exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were treated with a single TCDD dose of 5 μg/kg body weight (b.w.) and then for 3 weeks they were daily supplemented with tocopherol at a dose of 30 mg/kg b.w. The inflammation was initiated by intrapleural injection of a single dose of 1% carrageenin solution in a volume of 0.15 ml. Changes in biochemical blood parameters were measured three times at the 24th, 72nd and 120th hour of pleuritis and the blood was collected from 20 animals of each group of rats (group with the control inflammation; group treated with TCDD and with control inflammation; group treated with TCDD, supplemented with tocopherol and with the inflammation). The following biochemical parameters were measured: tumor necrosis factor (TNF), interleukin-1 (IL-1), IL-2, IL-4, IL-6, procollagen, telopeptide, fibrinogen, cholesterol, urea, creatinine, aspartate aminotransferase (AspAT) and alanine aminotransferase (AlAT). Daily supplementation of tocopherol caused significant changes in the level of TNF, IL-1, IL-4, IL-6, urea, creatinine, AspAT and AlAT. According to the results of these studies, we suggest that tocopherol supplementation in high doses could act as a protective treatment to improve liver metabolism.

  9. Soils containing 2,3,7,8-tetrachlorodibenzo-p-dioxin: aspects of their microbial activity and the potential for their microbially-mediated decontamination

    SciTech Connect

    Arthur, M.F.

    1987-01-01

    Three soils from Missouri and a soil from New Jersey, containing between 0.008 and 26.3 ug/g of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), were examined for microbial activity; the Missouri soils were also monitored for TCDD biodegradation. The objective was to simulate TCDD biodegradation by the indigenous microflora in order to develop a cost-effective method to decontaminate soils in situ. Microbial activity in TCDD soils was examined by enumeration of aerobic eutrophic and oligotrophic bacteria, actinomycetes, and fungi; determination of soil enzyme activity, including dehydrogenase, acid and alkaline phosphatase, arylsulfatase, and rhodanese; and measurement of soil respiration. The Missouri soils were subsequently amended with fertilizer, /sup 14/C-TCDD and a TCDD-solubilizing nonionic surfactant in order to improve the availability of TCDD to the indigenous soil microflora. Biodegradation of TCDD was monitored by the evolution of /sup 14/CO/sub 2/ and by high resolution gas chromatography/mass spectrometry (CC/MS).

  10. Phosphate Tether-Mediated Ring-Closing Metathesis for the Generation of P-Stereogenic, Z-Configured Bicyclo[7.3.1]- and Bicyclo[8.3.1]phosphates.

    PubMed

    Markley, Jana L; Maitra, Soma; Hanson, Paul R

    2016-02-01

    A phosphate tether-mediated ring-closing metathesis (RCM) study to the synthesis of Z-configured, P-stereogenic bicyclo[7.3.1]- and bicyclo[8.3.1]phosphates is reported. Investigations suggest that C3-substitution, olefin substitution, and proximity of the forming olefin to the bridgehead carbon of the bicyclic affect the efficiency and stereochemical outcome of the RCM event. This study demonstrates the utility of phosphate tether-mediated desymmetrization of C2-symmetric, 1,3-anti-diol-containing dienes in the generation of macrocyclic phosphates with potential synthetic and biological utility.

  11. Phosphate Tether-Mediated Ring-Closing Metathesis for the Generation of P-Stereogenic, Z-Configured Bicyclo[7.3.1]- and Bicyclo[8.3.1]phosphates.

    PubMed

    Markley, Jana L; Maitra, Soma; Hanson, Paul R

    2016-02-01

    A phosphate tether-mediated ring-closing metathesis (RCM) study to the synthesis of Z-configured, P-stereogenic bicyclo[7.3.1]- and bicyclo[8.3.1]phosphates is reported. Investigations suggest that C3-substitution, olefin substitution, and proximity of the forming olefin to the bridgehead carbon of the bicyclic affect the efficiency and stereochemical outcome of the RCM event. This study demonstrates the utility of phosphate tether-mediated desymmetrization of C2-symmetric, 1,3-anti-diol-containing dienes in the generation of macrocyclic phosphates with potential synthetic and biological utility. PMID:26794367

  12. Discovery of 8-Cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x) as a Potent Inhibitor of Cyclin-Dependent Kinase 4 (CDK4) and AMPK-Related Kinase 5 (ARK5)

    PubMed Central

    2015-01-01

    The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure–activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30–100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure–activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound. PMID:24417566

  13. Discovery of 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x) as a potent inhibitor of cyclin-dependent kinase 4 (CDK4) and AMPK-related kinase 5 (ARK5).

    PubMed

    Reddy, M V Ramana; Akula, Balireddy; Cosenza, Stephen C; Athuluridivakar, Saikrishna; Mallireddigari, Muralidhar R; Pallela, Venkat R; Billa, Vinay K; Subbaiah, D R C Venkata; Bharathi, E Vijaya; Vasquez-Del Carpio, Rodrigo; Padgaonkar, Amol; Baker, Stacey J; Reddy, E Premkumar

    2014-02-13

    The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure-activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30-100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure-activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound.

  14. Synthesis, molecular modeling, and opioid receptor affinity of 9, 10-diazatricyclo[4.2.1.1(2,5)]decanes and 2,7-diazatricyclo[4.4.0. 0(3,8)]decanes structurally related to 3,8-diazabicyclo[3.2. 1]octanes.

    PubMed

    Vianello, P; Albinati, A; Pinna, G A; Lavecchia, A; Marinelli, L; Borea, P A; Gessi, S; Fadda, P; Tronci, S; Cignarella, G

    2000-06-01

    Various lines of evidence, including molecular modeling studies, imply that the endoethylenic bridge of 3,8-diazabicyclo[3.2. 1]octanes (DBO, 1) plays an essential role in modulating affinity toward mu opioid receptors. This hypothesis, together with the remarkable analgesic properties observed for N(3) propionyl, N(8) arylpropenyl derivatives (2) and of the reverted isomers (3), has prompted us to insert an additional endoethylenic bridge on the piperazine moiety in order to identify derivatives with increased potency toward this receptor class. In the present report, we describe the synthesis of the novel compounds 9,10-diazatricyclo[4.2. 1.1(2,5)]decane (4) and 2,7-diazatricyclo[4.4.0.0(3,8)]decane (5), as well as the representative derivatives functionalized at the two nitrogen atoms by propionyl and arylpropenyl groups (6a-e, 7a-d). Opioid receptor binding assays revealed that, among the compounds tested, the N-propionyl-N-cinnamyl derivatives 6a and 7a exhibited the highest mu-receptor affinity, and remarkably, compound 7a displayed in vivo (mice) an analgesic potency 6-fold that of morphine.

  15. Paternal occupational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin and birth outcomes of offspring: birth weight, preterm delivery, and birth defects.

    PubMed

    Lawson, Christina C; Schnorr, Teresa M; Whelan, Elizabeth A; Deddens, James A; Dankovic, David A; Piacitelli, Laurie A; Sweeney, Marie H; Connally, L Barbara

    2004-10-01

    Agent Orange is a phenoxy herbicide that was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We studied pregnancy outcomes among wives of male chemical workers who were highly exposed to chemicals contaminated with TCDD and among wives of nonexposed neighborhood referents. For exposed pregnancies, we estimated serum TCDD concentration at the time of conception using a pharmacokinetic model. The mean TCDD concentration for workers' births was 254 pg/g lipid (range, 3-16,340 pg/g). The mean referent concentration of 6 pg/g was assigned to pregnancies fathered by workers before exposure. A total of 1,117 live singleton births of 217 referent wives and 176 worker wives were included. Only full-term births were included in the birth weight analysis (greater than or equal to 37 weeks of gestation). Mean birth weight among full-term babies was similar among referents' babies (n = 604), preexposure workers' babies (n = 221), and exposed workers' babies (n = 292) (3,420, 3,347, and 3,442 g, respectively). Neither continuous nor categorical TCDD concentration had an effect on birth weight for term infants after adjustment for infant sex, mother's education, parity, prenatal cigarette smoking, and gestation length. An analysis to estimate potential direct exposure of the wives during periods of workers' exposure yielded a nonstatistically significant increase in infant birth weight of 130 g in the highest exposure group (TCDD concentration > 254 pg/g) compared with referents (p = 0.09). Mothers' reports of preterm delivery showed a somewhat protective association with paternal TCDD (log) concentration (odds ratio = 0.8; 95% confidence interval, 0.6-1.1). We also include descriptive information on reported birth defects. Because the estimated TCDD concentrations in this population were much higher than in other studies, the results indicate that TCDD is unlikely to increase the risk of low birth weight or preterm delivery through a paternal mechanism. Key words

  16. A Study of 2,3,7,8-Tetrachlorodibenzo-p-dioxin Induced Liver Injury in Jian Carp (Cyprinus carpio var. Jian) Using Precision-Cut Liver Slices.

    PubMed

    Du, Jin-Liang; Cao, Li-Ping; Liu, Ying-Juan; Jia, Rui; Yin, Guo-Jun

    2016-01-01

    The aim of this study was to establish a model for the study of liver injury induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in Jian carp using precision-cut liver slices (PCLS). PCLS were treated with TCDD at concentrations of 0, 0.05, 0.1, 0.3, and 0.6 μg/L for 6 h, followed by collection of the culture supernatant and PCLS for analysis. Several biochemical indices were analyzed, including glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA). Expression of mRNA was also estimated for cytochrome P4501A (CYP1A), aryl hydrocarbon receptor2 (AhR2), and aryl hydrocarbon receptor nuclear translocator2 (ARNT2). Results showed that some significant effects (p < 0.05) in MDA, GSH-Px and PCLS viability were observed at a TCDD concentration as low as 0.05 µg/L, and the observed effects increased with exposure concentration. Following exposure to TCDD for 6 h at a concentration of 0.3 μg/L, significant increases (p < 0.01) in the content of GPT, GOT, MDA, and LDH were observed, while SOD activity, GSH-Px activity, and PCLS viability were decreased (p < 0.01 or p < 0.05). Exposure to 0.3 μg/L TCDD also resulted in increased expression of mRNA for CYP1A, AhR2, and ARNT2. Overall, these results provide evidence of TCDD-induced liver injury and oxidative stress in Jian carp. These results also support the use of PCLS as an in vitro model for the evaluation of hepatotoxicity in Jian carp.

  17. Production of Biologically Active 7,10-dihydroxy-8(E)-octadecenoic Acid from Korean Pine Seed Oil by Pseudomonas aeruginosa PR3.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydroxyl group of hydroxyl fatty acid (HFA) cause HFA to carry special properties such as higher viscosity and reactivity compared with other non-hydroxy fatty acids. Microbial conversion of oleic acid into 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) caused DOD to carry strong antibacterial activit...

  18. 8 CFR 248.3 - Application.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CHANGE OF NONIMMIGRANT CLASSIFICATION § 248.3 Application. Requests for a change of status must be filed on the form designated by USCIS with the fee prescribed in 8 CFR 103.7(b) and in accordance with the form instructions. (a) Petition...

  19. DFT studies on a high-energy density cage compound 1, 3, 5, 7, 9, 11-hexo(N(CH3)NO2)-2, 4, 6, 8, 10, 12-hexaazatetracyclo[5, 5, 0, 0, 0] dodecane

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Hong; Yong, Yong-Liang; Zhang, Xian-Zhou

    2014-04-01

    The infrared and Raman spectra, heat of formation (HOF) and thermodynamic properties were investigated by B3LYP/6-31G** method for a new designed polynitro cage compound 1,3,5,7,9,11-hexo(N(CH3)NO2)-2,4,6,8,10,12-hexaazatetracyclo[5,5,0,0,0]dodecane. The detonation velocity (D) and pressure (P) were predicted by the Kamlet-Jacobs equations based on the theoretical density and condensed HOF. The bond dissociation energies and bond orders for the weakest bonds were analysed to investigate the thermal stability of the title compound. The computational result shows that the detonation velocity and pressure of the title compound are superior to those of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), but inferior to those of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) and hexanitrohexaazaisowurtzitane (HNIW). And the analysis of thermal stability shows that the first step of pyrolysis is the rupture of the N7-NO2 bond. The crystal structure obtained by molecular mechanics belongs to the P21 space group, with the lattice parameters Z = 2, a = 11.8246 Å, b = 10.4632 Å, c = 15.9713 Å, ρ = 1.98 g cm-3.

  20. Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 nanowires for energy harvesting

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi; Bowland, Christopher C.; Malakooti, Mohammad H.; Tang, Haixiong; Sodano, Henry A.

    2016-02-01

    Lead-free piezoelectric nanowires (NWs) show strong potential in sensing and energy harvesting applications due to their flexibility and ability to convert mechanical energy to electric energy. Currently, most lead-free piezoelectric NWs are produced through low yield synthesis methods and result in low electromechanical coupling, which limit their efficiency as energy harvesters. In order to alleviate these issues, a scalable method is developed to synthesize perovskite type 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) NWs with high piezoelectric coupling coefficient. The piezoelectric coupling coefficient of the BZT-BCT NWs is measured by a refined piezoresponse force microscopy (PFM) testing method and shows the highest reported coupling coefficient for lead-free piezoelectric nanowires of 90 +/- 5 pm V-1. Flexible nanocomposites utilizing dispersed BZT-BCT NWs are fabricated to demonstrate an energy harvesting application with an open circuit voltage of up to 6.25 V and a power density of up to 2.25 μW cm-3. The high electromechanical coupling coefficient and high power density demonstrated with these lead-free NWs produced via a scalable synthesis method shows the potential for high performance NW-based devices.