Sample records for accumulating high levels

  1. The HSP terminator of Arabidopsis thaliana induces a high level of miraculin accumulation in transgenic tomatoes.

    PubMed

    Hirai, Tadayoshi; Kurokawa, Natsuko; Duhita, Narendra; Hiwasa-Tanase, Kyoko; Kato, Kazuhisa; Kato, Ko; Ezura, Hiroshi

    2011-09-28

    High-level accumulation of the target recombinant protein is a significant issue in heterologous protein expression using transgenic plants. Miraculin, a taste-modifying protein, was accumulated in transgenic tomatoes using an expression cassette in which the miraculin gene was expressed by the cauliflower mosaic virus (CaMV) 35S promoter and the heat shock protein (HSP) terminator (MIR-HSP). The HSP terminator was derived from heat shock protein 18.2 in Arabidopsis thaliana . Using this HSP-containing cassette, the miraculin concentration in T0 transgenic tomato lines was 1.4-13.9% of the total soluble protein (TSP), and that in the T1 transgenic tomato line homozygous for the miraculin gene reached 17.1% of the TSP. The accumulation level of the target protein was comparable to levels observed with chloroplast transformation. The high-level accumulation of miraculin in T0 transgenic tomato lines achieved by the HSP terminator was maintained in the successive T1 generation, demonstrating the genetic stability of this accumulation system.

  2. Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

    NASA Astrophysics Data System (ADS)

    Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.; Kruger, Albert A.

    2017-11-01

    The effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr)2O4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/or small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. The accumulation rate of ∼53.8 ± 3.7 μm/h determined for this glass will result in a ∼26 mm-thick layer after 20 days of melter idling.

  3. Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.

    We present that the effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr) 2O 4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/ormore » small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. In conclusion, the accumulation rate of ~53.8 ± 3.7 μm/h determined for this glass will result in a ~26 mm-thick layer after 20 days of melter idling.« less

  4. Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

    DOE PAGES

    Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.; ...

    2017-08-30

    We present that the effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr) 2O 4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/ormore » small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. In conclusion, the accumulation rate of ~53.8 ± 3.7 μm/h determined for this glass will result in a ~26 mm-thick layer after 20 days of melter idling.« less

  5. Effects of high ammonium level on biomass accumulation of common duckweed Lemna minor L.

    PubMed

    Wang, Wenguo; Yang, Chuang; Tang, Xiaoyu; Gu, Xinjiao; Zhu, Qili; Pan, Ke; Hu, Qichun; Ma, Danwei

    2014-12-01

    Growing common duckweed Lemna minor L. in diluted livestock wastewater is an alternative option for pollutants removal and consequently the accumulated duckweed biomass can be used for bioenergy production. However, the biomass accumulation can be inhibited by high level of ammonium (NH4 (+)) in non-diluted livestock wastewater and the mechanism of ammonium inhibition is not fully understood. In this study, the effect of high concentration of NH4 (+) on L. minor biomass accumulation was investigated using NH4 (+) as sole source of nitrogen (N). NH4 (+)-induced toxicity symptoms were observed when L. minor was exposed to high concentrations of ammonium nitrogen (NH4 (+)-N) after a 7-day cultivation. L. minor exposed to the NH4 (+)-N concentration of 840 mg l(-1) exhibited reduced relative growth rate, contents of carbon (C) and photosynthetic pigments, and C/N ratio. Ammonium irons were inhibitory to the synthesis of photosynthetic pigments and caused C/N imbalance in L. minor. These symptoms could further cause premature senescence of the fronds, and restrain their reproduction, growth and biomass accumulation. L. minor could grow at NH4 (+)-N concentrations of 7-84 mg l(-1) and the optimal NH4 (+)-N concentration was 28 mg l(-1).

  6. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fox, K. M.; Fowley, M. D.; Miller, D. H.

    2016-05-01

    The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer atmore » the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.« less

  7. Comparative Polygenic Analysis of Maximal Ethanol Accumulation Capacity and Tolerance to High Ethanol Levels of Cell Proliferation in Yeast

    PubMed Central

    Pais, Thiago M.; Foulquié-Moreno, María R.; Hubmann, Georg; Duitama, Jorge; Swinnen, Steve; Goovaerts, Annelies; Yang, Yudi; Dumortier, Françoise; Thevelein, Johan M.

    2013-01-01

    The yeast Saccharomyces cerevisiae is able to accumulate ≥17% ethanol (v/v) by fermentation in the absence of cell proliferation. The genetic basis of this unique capacity is unknown. Up to now, all research has focused on tolerance of yeast cell proliferation to high ethanol levels. Comparison of maximal ethanol accumulation capacity and ethanol tolerance of cell proliferation in 68 yeast strains showed a poor correlation, but higher ethanol tolerance of cell proliferation clearly increased the likelihood of superior maximal ethanol accumulation capacity. We have applied pooled-segregant whole-genome sequence analysis to identify the polygenic basis of these two complex traits using segregants from a cross of a haploid derivative of the sake strain CBS1585 and the lab strain BY. From a total of 301 segregants, 22 superior segregants accumulating ≥17% ethanol in small-scale fermentations and 32 superior segregants growing in the presence of 18% ethanol, were separately pooled and sequenced. Plotting SNP variant frequency against chromosomal position revealed eleven and eight Quantitative Trait Loci (QTLs) for the two traits, respectively, and showed that the genetic basis of the two traits is partially different. Fine-mapping and Reciprocal Hemizygosity Analysis identified ADE1, URA3, and KIN3, encoding a protein kinase involved in DNA damage repair, as specific causative genes for maximal ethanol accumulation capacity. These genes, as well as the previously identified MKT1 gene, were not linked in this genetic background to tolerance of cell proliferation to high ethanol levels. The superior KIN3 allele contained two SNPs, which are absent in all yeast strains sequenced up to now. This work provides the first insight in the genetic basis of maximal ethanol accumulation capacity in yeast and reveals for the first time the importance of DNA damage repair in yeast ethanol tolerance. PMID:23754966

  8. Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.

    The effectiveness of HLW vitrification is limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr)2O4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layer, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/or small-scale agglomerates, but, excessive agglomeration observed in high-Ni-Fe glass resulted in an under-prediction ofmore » accumulated layers, which gradually worsen over time as an increased number of agglomerates formed. Accumulation rate of ~53.8 ± 3.7 µm/h determined for this glass will result in ~26 mm thick layer in 20 days of melter idling.« less

  9. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter: Summary of 2017 experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fox, K.; Fowley, M.

    A full-scale, transparent mock-up of the Hanford Tank Waste Treatment and Immobilization Project High Level Waste glass melter riser and pour spout has been constructed to allow for testing with visual feedback of particle settling, accumulation, and resuspension when operating with a controlled fraction of crystals in the glass melt. Room temperature operation with silicone oil and magnetite particles simulating molten glass and spinel crystals, respectively, allows for direct observation of flow patterns and settling patterns. The fluid and particle mixture is recycled within the system for each test.

  10. A High Serum Iron Level Causes Mouse Retinal Iron Accumulation Despite an Intact Blood-Retinal Barrier

    PubMed Central

    Zhao, Liangliang; Li, Yafeng; Song, Delu; Song, Ying; Theurl, Milan; Wang, Chenguang; Cwanger, Alyssa; Su, Guanfang; Dunaief, Joshua L.

    2015-01-01

    The retina can be shielded by the blood-retinal barrier. Because photoreceptors are damaged by excess iron, it is important to understand whether the blood-retinal barrier protects against high serum iron levels. Bone morphogenic protein 6 (Bmp6) knockout mice have serum iron overload. Herein, we tested whether the previously documented retinal iron accumulation in Bmp6 knockout mice might result from the high serum iron levels or, alternatively, low levels of retinal hepcidin, an iron regulatory hormone whose transcription can be up-regulated by Bmp6. Furthermore, to determine whether increases in serum iron can elevate retinal iron levels, we i.v. injected iron into wild-type mice. Retinas were analyzed by real-time quantitative PCR and immunofluorescence to assess the levels of iron-regulated genes/proteins and oxidative stress. Retinal hepcidin mRNA levels in Bmp6 knockout retinas were the same as, or greater than, those in age-matched wild-type retinas, indicating that Bmp6 knockout does not cause retinal hepcidin deficiency. Changes in mRNA levels of L ferritin and transferrin receptor indicated increased retinal iron levels in i.v. iron-injected wild-type mice. Oxidative stress markers were elevated in photoreceptors of mice receiving i.v. iron. These findings suggest that elevated serum iron levels can overwhelm local retinal iron regulatory mechanisms. PMID:25174877

  11. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter: Summary of FY2016 experiements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fox, K.; Fowley, M.; Miller, D.

    2016-12-01

    Five experiments were completed with the full-scale, room temperature Hanford Waste Treatment and Immobilization Plant (WTP) high-level waste (HLW) melter riser test system to observe particle flow and settling in support of a crystal tolerant approach to melter operation. A prototypic pour rate was maintained based on the volumetric flow rate. Accumulation of particles was observed at the bottom of the riser and along the bottom of the throat after each experiment. Measurements of the accumulated layer thicknesses showed that the settled particles at the bottom of the riser did not vary in thickness during pouring cycles or idle periods.more » Some of the settled particles at the bottom of the throat were re-suspended during subsequent pouring cycles, and settled back to approximately the same thickness after each idle period. The cause of the consistency of the accumulated layer thicknesses is not year clear, but was hypothesized to be related to particle flow back to the feed tank. Additional experiments reinforced the observation of particle flow along a considerable portion of the throat during idle periods. Limitations of the system are noted in this report and may be addressed via future modifications. Follow-on experiments will be designed to evaluate the impact of pouring rate on particle re-suspension, the influence of feed tank agitation on particle accumulation, and the effect of changes in air lance positioning on the accumulation and re-suspension of particles at the bottom of the riser. A method for sampling the accumulated particles will be developed to support particle size distribution analyses. Thicker accumulated layers will be intentionally formed via direct addition of particles to select areas of the system to better understand the ability to continue pouring and re-suspend particles. Results from the room temperature system will be correlated with observations and data from the Research Scale Melter (RSM) at Pacific Northwest National

  12. Proline accumulation in baker's yeast enhances high-sucrose stress tolerance and fermentation ability in sweet dough.

    PubMed

    Sasano, Yu; Haitani, Yutaka; Ohtsu, Iwao; Shima, Jun; Takagi, Hiroshi

    2012-01-03

    During bread-making processes, yeast cells are exposed to various baking-associated stresses. High-sucrose concentrations exert severe osmotic stress that seriously damages cellular components by generation of reactive oxygen species (ROS). Previously, we found that the accumulation of proline conferred freeze-thaw stress tolerance and the baker's yeast strain that accumulated proline retained higher-level fermentation abilities in frozen doughs than the wild-type strain. In this study, we constructed self-cloning diploid baker's yeast strains that accumulate proline. These resultant strains showed higher cell viability and lower intracellular oxidation levels than that observed in the wild-type strain under high-sucrose stress condition. Proline accumulation also enhanced the fermentation ability in high-sucrose-containing dough. These results demonstrate the usefulness of proline-accumulating baker's yeast for sweet dough baking. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Increasing catechin and procyanindin accumulation in high-CO2-treated Fragaria vesca strawberries.

    PubMed

    Blanch, María; Alvarez, Inma; Sanchez-Ballesta, María T; Escribano, María I; Merodio, Carmen

    2012-08-01

    This paper deals with the impact of low temperature and high CO2 levels on flavonols, proanthocyanidins, and anthocyanins, synthesized via branched pathways from common precursors, in strawberries (Fragaria vesca L.). Flavonoids were identified with Q-TOF equipment and quantified by HPLC-quadrupole. Proanthocyanins B1 and B3 accumulated in CO2-treated strawberries, whereas in untreated (air) fruit, flavonoid production was redirected toward anthocyanin accumulation with a sharp decrease in catechin and procyanidin B3 levels. Moreover, in CO2-treated fruit, mainly in those with 20% CO2, anthocyanin accumulation did not decline. Due to its antifungal activity, catechin induction in CO2-treated strawberries could explain the capacity of high CO2 treatments to reduce fungal decay. Ascorbic acid content increased in 40% CO2-treated fruits, whereas in those treated with 20% CO2 an increase in flavonol content was observed. Despite these differences, similar antioxidant capacities were found in untreated and CO2-treated Mara de Bois strawberries.

  14. Leucine Biosynthesis Is Involved in Regulating High Lipid Accumulation in Yarrowia lipolytica

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kerkhoven, Eduard J.; Kim, Young-Mo; Wei, Siwei

    ABSTRACT The yeastYarrowia lipolyticais a potent accumulator of lipids, and lipogenesis in this organism can be influenced by a variety of factors, such as genetics and environmental conditions. Using a multifactorial study, we elucidated the effects of both genetic and environmental factors on regulation of lipogenesis inY. lipolyticaand identified how two opposite regulatory states both result in lipid accumulation. This study involved comparison of a strain overexpressing diacylglycerol acyltransferase (DGA1) with a control strain grown under either nitrogen or carbon limitation conditions. A strong correlation was observed between the responses on the transcript and protein levels. Combination ofDGA1overexpression with nitrogen limitationmore » resulted in a high level of lipid accumulation accompanied by downregulation of several amino acid biosynthetic pathways, including that of leucine in particular, and these changes were further correlated with a decrease in metabolic fluxes. This downregulation was supported by the measured decrease in the level of 2-isopropylmalate, an intermediate of leucine biosynthesis. Combining the multi-omics data with putative transcription factor binding motifs uncovered a contradictory role for TORC1 in controlling lipid accumulation, likely mediated through 2-isopropylmalate and a Leu3-like transcription factor. IMPORTANCEThe ubiquitous metabolism of lipids involves refined regulation, and an enriched understanding of this regulation would have wide implications. Various factors can influence lipid metabolism, including the environment and genetics. We demonstrated, using a multi-omics and multifactorial experimental setup, that multiple factors affect lipid accumulation in the yeastYarrowia lipolytica. Using integrative analysis, we identified novel interactions between nutrient restriction and genetic factors involving regulators that are highly conserved among eukaryotes. Given that lipid metabolism is involved in many

  15. Accumulate Repeat Accumulate Coded Modulation

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

  16. Intraspecific variation in cadmium tolerance and accumulation of a high-biomass tropical tree Averrhoa carambola L.: implication for phytoextraction.

    PubMed

    Dai, Zi-yun; Shu, Wen-sheng; Liao, Bin; Wan, Cai-yun; Li, Jin-tian

    2011-06-01

    Averrhoa carambola L., a high-biomass tropical tree, has recently been shown to be a strong accumulator of cadmium (Cd) and has great potential for Cd phytoextraction. In the present study, field studies and a controlled-environment experiment were combined to establish the extent of variation in Cd tolerance and accumulation at the cultivar level using 14 to 19 cultivars of A. carambola. The results indicated that all cultivars tested could accumulate Cd at high but different levels, and that Cd tolerance also varied greatly between these cultivars. It is confirmed that the high Cd tolerance and accumulation capacity are species-level and constitutional traits in A. carambola. However, no correlation was detected between tolerance index and accumulation of Cd in different cultivars, suggesting that the two traits are independent in this woody Cd accumulator. More importantly, cultivar Wuchuan Sweet (WCT) was shown to have the highest Cd-extraction potential; it yielded a high shoot biomass of 30 t ha(-1) in 230 d, and extracted 330 g ha(-1) Cd in the aerial tissues grown in Cd-contaminated field soil, which accounted for 12.8% of the total soil Cd in the top 20 cm of the soil profile.

  17. Levels of Lycopene β-Cyclase 1 Modulate Carotenoid Gene Expression and Accumulation in Daucus carota

    PubMed Central

    Moreno, Juan Camilo; Pizarro, Lorena; Fuentes, Paulina; Handford, Michael; Cifuentes, Victor; Stange, Claudia

    2013-01-01

    Plant carotenoids are synthesized and accumulated in plastids through a highly regulated pathway. Lycopene β-cyclase (LCYB) is a key enzyme involved directly in the synthesis of α-carotene and β-carotene through the cyclization of lycopene. Carotenoids are produced in both carrot (Daucus carota) leaves and reserve roots, and high amounts of α-carotene and β-carotene accumulate in the latter. In some plant models, the presence of different isoforms of carotenogenic genes is associated with an organ-specific function. D. carota harbors two Lcyb genes, of which DcLcyb1 is expressed in leaves and storage roots during carrot development, correlating with an increase in carotenoid levels. In this work, we show that DcLCYB1 is localized in the plastid and that it is a functional enzyme, as demonstrated by heterologous complementation in Escherichia coli and over expression and post transcriptional gene silencing in carrot. Transgenic plants with higher or reduced levels of DcLcyb1 had incremented or reduced levels of chlorophyll, total carotenoids and β-carotene in leaves and in the storage roots, respectively. In addition, changes in the expression of DcLcyb1 are accompanied by a modulation in the expression of key endogenous carotenogenic genes. Our results indicate that DcLcyb1 does not possess an organ specific function and modulate carotenoid gene expression and accumulation in carrot leaves and storage roots. PMID:23555569

  18. Enrichments of methanotrophic-heterotrophic cultures with high poly-β-hydroxybutyrate (PHB) accumulation capacities.

    PubMed

    Zhang, Tingting; Wang, Xiaowei; Zhou, Jiti; Zhang, Yu

    2018-03-01

    Methanotrophic-heterotrophic communities were selectively enriched from sewage sludge to obtain a mixed culture with high levels of poly-β-hydroxybutyrate (PHB) accumulation capacity from methane. Methane was used as the carbon source, N 2 as sole nitrogen source, and oxygen and Cu content were varied. Copper proved essential for PHB synthesis. All cultures enriched with Cu could accumulate high content of PHB (43.2%-45.9%), while only small amounts of PHB were accumulated by cultures enriched without Cu (11.9%-17.5%). Batch assays revealed that communities grown with Cu and a higher O 2 content synthesized more PHB, which had a wider optimal CH 4 :O 2 range and produced a high PHB content (48.7%) even though in the presence of N 2 . In all methanotrophic-heterotrophic communities, both methanotrophic and heterotrophic populations showed the ability to accumulate PHB. Although methane was added as the sole carbon source, heterotrophs dominated with abundances between 77.2% and 85.6%. All methanotrophs detected belonged to type II genera, which formed stable communities with heterotrophs of different PHB production capacities. Copyright © 2017. Published by Elsevier B.V.

  19. Elevated Levels of Dickkopf-1 Are Associated with β-Catenin Accumulation and Poor Prognosis in Patients with Chondrosarcoma

    PubMed Central

    Chen, Changbao; Zhou, Hua; Zhang, Xiaolin; Ma, Xinlong; Liu, Zhongjun; Liu, Xiaoguang

    2014-01-01

    Background Dickkopf-1 (DKK1) is an antagonist of Wnt/β-catenin signaling implicated in tumorigenesis. However, the biological role of DKK1 and β-catenin involved in chondrosarcoma has not been sufficiently investigated. This study was designed to investigate the expression profiles of DKK1 and β-catenin, and to clarify their clinical values in chondrosarcoma. Methods The mRNA and protein levels of DKK1 and β-catenin in fresh chondrosarcoma and the corresponding non-tumor tissues were analyzed by Real-time PCR and Western blot, respectively. The protein expression patterns of DKK1 and β-catenin were investigated by immunohistochemistry. The associations among DKK1 level, β-catenin accumulation, clinicopathological factors and the overall survival were separately evaluated. Results Both DKK1 and β-catenin levels were remarkably elevated in chondrosarcoma compared with the corresponding non-tumor tissues. High DKK1 level and positive β-catenin accumulation in chondrosarcoma specimens were 58.7% and 53.9%, respectively. Elevated DKK1 level significantly correlated with positive β-catenin accumulation, and they were remarkably associated with histological grade and Musculoskeletal Tumor Society stage. Furthermore, DKK1 level and β-catenin accumulation had significant impacts on the prognosis of chondrosarcoma patients. Multivariate analysis revealed that DKK1 level was an independent prognostic factor for overall survival. Conclusions Elevated DKK1 levels associated with β-catenin accumulation play a crucial role in chondrosarcoma. DKK1 can serve as a novel predictor of poor prognosis in patients with chondrosarcoma. PMID:25144498

  20. [Effects of nitrogen application level on soil nitrate accumulation and ammonia volatilization in high-yielding wheat field].

    PubMed

    Wang, Dong; Yu, Zhenwen; Yu, Wenming; Shi, Yu; Zhou, Zhongxin

    2006-09-01

    The study showed that during the period from sowing to pre-wintering, the soil nitrate in high-yielding wheat field moved down to deeper layers, and accumulated in the layers below 140 cm. An application rate of 96-168 kg N x hm(-2) increased the nitrate content in 0-60 cm soil layer and the wheat grain yield and its protein content, and decreased the proportion of apparent N loss to applied N and the ammonia volatilization loss from basal nitrogen. Applying 240 kg N x hm(-2) promoted the downward movement of soil nitrate and its accumulation in deeper layers, increased the proportion of apparent N loss to applied N and the ammonia volatilization loss from basal nitrogen, had no significant effect on the protein content of wheat grain, but decreased the grain yield. The appropriate application rate of nitrogen on high-yielding wheat field was 132-204 kg N x hm(-2).

  1. High-Level Accumulation of Triacylglycerol and Starch in Photoautotrophically Grown Chlamydomonas debaryana NIES-2212.

    PubMed

    Toyoshima, Masakazu; Sato, Naoki

    2015-12-01

    Microalgae have the potential to produce triacylglycerol (TAG) and starch, which provide alternative sources of biofuel. A problem in using Chlamydomonas reinhardtii as a model for TAG production has been that this alga lacks phosphatidylcholine (PC), which is thought to be important for TAG synthesis in plants. We found that C. debaryana is one of the rare species of Chlamydomonas having PC. Here we show that this strain, grown under complete photoautotrophic conditions, accumulated TAG and starch up to 20 and 250 pg per cell, respectively, during the stationary phase without nutrient deprivation. Addition of nutrients in this state did not cause loss of TAG, which was found in dilution with fresh medium. The photosynthetically produced TAG contained a high level of monounsaturated fatty acids, which is a preferred property as a material for biodiesel. The oil bodies were present in the cytoplasm, either between the cytoplasmic membrane and the chloroplast or between the chloroplast and the nucleus, whereas the starch granules were present within the chloroplast. Oil bodies were also deposited as a broad layer in the peripheral space of the cytoplasm outside the chloroplast, and might be easily released from the cells by genetic, chemical or mechanical manipulation. These results suggest that C. debaryana is a promising seed organism for developing a good biofuel producer. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Accumulate-Repeat-Accumulate-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

    2007-01-01

    Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

  3. Glycine betaine accumulation, ionic and water relations of red-beet at contrasting levels of sodium supply

    NASA Technical Reports Server (NTRS)

    Subbarao, G. V.; Wheeler, R. M.; Levine, L. H.; Stutte, G. W.; Sager, J. C. (Principal Investigator)

    2001-01-01

    Exposure of plants to sodium (Na) and salinity may increase glycine betaine accumulation in tissues. To study this, red-beet cvs. Scarlet Supreme and Ruby Queen, were grown for 42 days in a growth chamber using a re-circulating nutrient film technique with 0.25 mmol/L K and either 4.75 mmol/L (control) or 54.75 mmol/L (saline) Na (as NaCl). Plants were harvested at weekly intervals and measurements were taken on leaf water relations, leaf photosynthetic rates, chlorophyll fluorescence, chlorophyll levels, glycine betaine levels, and tissue elemental composition. Glycine betaine accumulation increased under salinity and this accumulation correlated with higher tissue levels of Na in both cultivars. Na accounted for 80 to 90% of the total cation uptake under the saline treatment. At final harvest (42 days), K concentrations in laminae ranged from approximately 65-95 micromoles g-1 dry matter (DM), whereas Na in shoot tissue ranged from approximately 3000-4000 micromoles g-1. Leaf sap osmotic potential at full turgor [psi(s100)] increased as lamina Na content increased. Glycine betaine levels of leaf laminae showed a linear relationship with leaf sap [psi(s100)]. Chlorophyll levels, leaf photosynthetic rates, and chlorophyll fluorescence were not affected by Na levels. These results suggest that the metabolic tolerance to high levels of tissue Na in red-beet could be due to its ability to synthesize and regulate glycine betaine production, and to control partitioning of Na and glycine betaine between the vacuole and the cytoplasm.

  4. Manganese peroxidase from the white-rot fungus Phanerochaete chrysosporium is enzymatically active and accumulates to high levels in transgenic maize seed.

    PubMed

    Clough, Richard C; Pappu, Kameshwari; Thompson, Kevin; Beifuss, Katherine; Lane, Jeff; Delaney, Donna E; Harkey, Robin; Drees, Carol; Howard, John A; Hood, Elizabeth E

    2006-01-01

    Manganese peroxidase (MnP) has been implicated in lignin degradation and thus has potential applications in pulp and paper bleaching, enzymatic remediation and the textile industry. Transgenic plants are an emerging protein expression platform that offer many advantages over traditional systems, in particular their potential for large-scale industrial enzyme production. Several plant expression vectors were created to evaluate the accumulation of MnP from the wood-rot fungus Phanerochaete chrysosporium in maize seed. We showed that cell wall targeting yielded full-length MnP, whereas cytoplasmic localization resulted in multiple truncated peroxidase polypeptides as detected by immunoblot analysis. In addition, the use of a seed-preferred promoter dramatically increased the expression levels and reduced the negative effects on plant health. Multiple independent transgenic lines were backcrossed with elite inbred corn lines for several generations with the maintenance of high-level expression, indicating genetic stability of the transgene.

  5. Correlation between calcium and phosphate levels to calculus accumulation on coronary heart disease patients

    NASA Astrophysics Data System (ADS)

    Cahaya, Cindy; Masulili, Sri Lelyati C.; Lessang, Robert; Radi, Basuni

    2017-02-01

    Coronary Artery Disease (CAD) or Coronary Heart Disease (CHD) is a disease that happened because of blood flow being blocked by atherosclerosis. Atherosclerosis is a process of hardening of the arteries which characterized by thickening and loss of elasticity of the intimal layer of vascular wall, by lipid deposit. Periodontitis is a chronic multifactorial inflammatory disease caused by microorganism and characterized by progressive destruction of the tooth supporting apparatus leading to tooth loss. Many studies use saliva as a valuable source for clinically information, as an asset for early diagnosis, prognostic and reviewer for pascatherapy status. Dental calculus had happened as a consequence of saliva supersaturation by calcium and phosphate. Salivary flow rate and its composition influence the formation of calculus. Increasing salivary calcium levels is characteristic of periodontitis patients. An important hipotesis in Cardiology is chronic infections contribute in atherosclerosis. Objective: To analyse the correlation between calcium and phosphate levels in saliva to calculus accumulation on CHD patients. Result: Correlation analysis between salivary calcium levels with calculus accumulation in patients with CHD and non-CHD showed no significant p value, p=0.59 and p=0.518. Correlation analysis between salivary phosphate levels and calculus accumulation showed no significant p value, p=0.836 for CHD patients and p=0.484 for non-CHD patients. Conclusion: There are no correlation between calcium levels and phosphate levels with calculus accumulation in CHD patients. Further research need to be done.

  6. Accumulate-Repeat-Accumulate-Accumulate-Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Sam; Thorpe, Jeremy

    2004-01-01

    Inspired by recently proposed Accumulate-Repeat-Accumulate (ARA) codes [15], in this paper we propose a channel coding scheme called Accumulate-Repeat-Accumulate-Accumulate (ARAA) codes. These codes can be seen as serial turbo-like codes or as a subclass of Low Density Parity Check (LDPC) codes, and they have a projected graph or protograph representation; this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded Repeat-and-Accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-lJ2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or Irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.

  7. Effects of dissolved oxygen level on cell growth and total lipid accumulation in the cultivation of Rhodotorula glutinis.

    PubMed

    Yen, Hong-Wei; Zhang, Zhiyong

    2011-07-01

    The total amount of lipids produced in Rhodotorula glutinis is a subject which has attracted increasing attention due to the potential biodiesel conversion from these microbial oils. The effects of the dissolved oxygen (DO) level in lipid accumulation were examined in this study. Variations of different medium volumes (30, 40 and 50ml) and shaking speed (60, 150 and 210rpm) in the flask trials were adopted to explore the DO effects on lipid production. All of the results revealed that a low DO could retard cell growth, while enhancing lipid accumulation. The 5l-fermentor results also confirm that a low DO (25 ± 10%) batch could have higher lipid content than that of high DO batch (60 ± 10%). Nevertheless, the DO level would not obviously affect the lipid composition profile. Oleic acid (C18:1) was the primary fatty acid in both batches. Due to the slow biomass growth rate resulting from the low DO, a two-stage DO controlled strategy (consisting of a high DO stage and following a low DO stage) was performed to improve the cell growth and lipid accumulation simultaneously. However, the strategy was not successful on the enhancement of total lipid production as compared to other batches. Conclusively, even a low DO could retard cell growth; the total production of lipids in the batch with low DO was higher that of the high DO batch due to the enhancement of lipid accumulation. Therefore, the batch operation of R. glutinis at the low DO was suggested for the purpose of lipid production. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  8. TRMM Version 7 Level 3 Gridded Monthly Accumulations of GPROF Precipitation Retrievals

    NASA Technical Reports Server (NTRS)

    Stocker, E. F.; Kelley, O. A.

    2012-01-01

    In July 2011, improved versions of the retrieval algorithms were approved for TRMM. All data starting with June 2011 are produced only with the version 7 code. At the same time, version 7 reprocessing of all TRMM mission data was started. By the end of August 2011, the 14+ years of the reprocessed mission data became available online to users. This reprocessing provided the opportunity to redo and enhance upon an analysis of V7 impacts on L3 data accumulations that was presented at the 2010 EGU General Assembly. This paper will discuss the impact of algorithm changes made in th GPROF retrieval on the Level 2 swath products. Perhaps the most important change in that retrieval was to replacement of a model based a priori database with one created from Precipitation Radar (PR) and TMI brightness temperature (Tb) data. The radar pays a major role in the V7 GPROF (GPROF2010) in determining existence of rain. The level 2 retrieval algorithm also introduced a field providing the probability of rain. This combined use of the PR has some impact on the retrievals and created areas, particularly over ocean, where many areas of low-probability precipitation are retrieved whereas in version 6, these areas contained zero rain rates. This paper will discuss how these impacts get translated to the space/time averaged monthly products that use the GPROF retrievals. The level 3 products discussed are the gridded text product 3G68 and the standard 3A12 and 3B31 products. The paper provides an overview of the changes and explanation of how the level 3 products dealt with the change in the retrieval approach. Using the .25 deg x .25 degree grid, the paper will show that agreement between the swath product and the level 3 remains very high. It will also present comparisons of V6 and V7 GPROF retrievals as seen both at the swath level and the level 3 time/space gridded accumulations. It will show that the various L3 products based on GPROF level 2 retrievals are in close agreement. The

  9. Successful high-level accumulation of fish oil omega-3 long-chain polyunsaturated fatty acids in a transgenic oilseed crop.

    PubMed

    Ruiz-Lopez, Noemi; Haslam, Richard P; Napier, Johnathan A; Sayanova, Olga

    2014-01-01

    Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of considerable interest, based on clear evidence of dietary health benefits and the concurrent decline of global sources (fish oils). Generating alternative transgenic plant sources of omega-3 LC-PUFAs, i.e. eicosapentaenoic acid (20:5 n-3, EPA) and docosahexaenoic acid (22:6 n-3, DHA) has previously proved problematic. Here we describe a set of heterologous genes capable of efficiently directing synthesis of these fatty acids in the seed oil of the crop Camelina sativa, while simultaneously avoiding accumulation of undesirable intermediate fatty acids. We describe two iterations: RRes_EPA in which seeds contain EPA levels of up to 31% (mean 24%), and RRes_DHA, in which seeds accumulate up to 12% EPA and 14% DHA (mean 11% EPA and 8% DHA). These omega-3 LC-PUFA levels are equivalent to those in fish oils, and represent a sustainable, terrestrial source of these fatty acids. We also describe the distribution of these non-native fatty acids within C. sativa seed lipids, and consider these data in the context of our current understanding of acyl exchange during seed oil synthesis. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  10. High-level expression of Camelid nanobodies in Nicotiana benthamiana.

    PubMed

    Teh, Yi-Hui Audrey; Kavanagh, Tony A

    2010-08-01

    Nanobodies (or VHHs) are single-domain antigen-binding fragments derived from Camelid heavy chain-only antibodies. Their small size, monomeric behaviour, high stability and solubility, and ability to bind epitopes not accessible to conventional antibodies make them especially suitable for many therapeutic and biotechnological applications. Here we describe high-level expression, in Nicotiana benthamiana, of three versions of an anti-hen egg white lysozyme (HEWL) nanobody which include the original VHH from an immunized library (cAbLys3), a codon-optimized derivative, and a codon-optimized hybrid nanobody comprising the CDRs of cAbLys3 grafted onto an alternative 'universal' nanobody framework. His6- and StrepII-tagged derivatives of each nanobody were targeted for accumulation in the cytoplasm, chloroplast and apoplast using different pre-sequences. When targeted to the apoplast, intact functional nanobodies accumulated at an exceptionally high level (up to 30% total leaf protein), demonstrating the great potential of plants as a nanobody production system.

  11. Copepods in Turbid Shallow Soda Lakes Accumulate Unexpected High Levels of Carotenoids

    PubMed Central

    Schneider, Tobias; Herzig, Alois; Koinig, Karin A.; Sommaruga, Ruben

    2012-01-01

    Carotenoids are protective pigments present in many aquatic organisms that reduce the photooxidative stress induced by short-wavelenght solar radiation, yet increase their susceptibility to predators. Arctodiaptomus spinosus, a calanoid copepod typically found in many fishless shallow soda lakes, shows large between-lake differences in pigmentation. Here, we attribute these differences to the environmental state of these ecosystems, namely, ‘dark water’ lakes with submersed vegetation and turbid ‘white’ lakes lacking macrophytes. Copepod carotenoid concentration in the turbid ‘white’ lakes was significantly (about 20-fold) higher than in the ‘dark water’ ones, although the latter systems were characterized by higher transparency. In addition, males had on a dry weight basis around three times higher carotenoid concentrations than females. Mycosporine-like amino acids (direct UV screening substances) were found in all cases, but in low concentration. The environmental conditions in these ecosystems were largely shaped by the presence/absence of submersed macrophytes Thus, in the turbid lakes, the strong wind-driven mixis allows for copepods to be brought to the surface and being exposed to solar radiation, whereas in ‘dark water’ ones, macrophytes reduce water turbulence and additionally provide shelter. Our results explain the counter-intuitive notion of strong red pigmentation in copepods from a turbid ecosystem and suggest that factors other than high UV transparency favor carotenoid accumulation in zooplankton. PMID:22916208

  12. Proteomics analysis of high lipid-producing strain Mucor circinelloides WJ11: an explanation for the mechanism of lipid accumulation at the proteomic level.

    PubMed

    Tang, Xin; Zan, Xinyi; Zhao, Lina; Chen, Haiqin; Chen, Yong Q; Chen, Wei; Song, Yuanda; Ratledge, Colin

    2016-02-11

    The oleaginous fungus, Mucor circinelloides, is attracting considerable interest as it produces oil rich in γ-linolenic acid. Nitrogen (N) deficiency is a common strategy to trigger the lipid accumulation in oleaginous microorganisms. Although a simple pathway from N depletion in the medium to lipid accumulation has been elucidated at the enzymatic level, global changes at protein levels upon N depletion have not been investigated. In this study, we have systematically analyzed the changes at the levels of protein expression in M. circinelloides WJ11, a high lipid-producing strain (36 %, lipid/cell dry weight), during lipid accumulation. Proteomic analysis demonstrated that N depletion increased the expression of glutamine synthetase, involved in ammonia assimilation, for the supply of cellular nitrogen but decreased the metabolism of amino acids. Upon N deficiency, many proteins (e.g., fructose-bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, enolase, pyruvate kinase) involved in glycolytic pathway were up-regulated while proteins involved in the tricarboxylic acid cycle (e.g., isocitrate dehydrogenase, succinyl-CoA ligase, succinate dehydrogenase, fumarate hydratase) were down-regulated, indicating this activity was retarded thereby leading to a greater flux of carbon into fatty acid biosynthesis. Moreover, glucose-6-phosphate dehydrogenase, transaldolase and transketolase, which participate in the pentose phosphate pathway, were up-regulated, leading to the increased production of NADPH, the reducing power for fatty acid biosynthesis. Furthermore, protein and nucleic acid metabolism were down-regulated and some proteins involved in energy metabolism, signal transduction, molecular chaperone and redox homeostasis were up-regulated upon N depletion, which may be the cellular response to the stress produced by the onset of N deficiency. N limitation increased those expressions of the proteins involved in ammonia assimilation but decreased that

  13. Relevance of GaAs(001) surface electronic structure for high frequency dispersion on n-type accumulation capacitance

    NASA Astrophysics Data System (ADS)

    Pi, T. W.; Chen, W. S.; Lin, Y. H.; Cheng, Y. T.; Wei, G. J.; Lin, K. Y.; Cheng, C.-P.; Kwo, J.; Hong, M.

    2017-01-01

    This study investigates the origin of long-puzzled high frequency dispersion on the accumulation region of capacitance-voltage characteristics in an n-type GaAs-based metal-oxide-semiconductor. Probed adatoms with a high Pauling electronegativity, Ag and Au, unexpectedly donate charge to the contacted As/Ga atoms of as-grown α2 GaAs(001)-2 × 4 surfaces. The GaAs surface atoms behave as charge acceptors, and if not properly passivated, they would trap those electrons accumulated at the oxide and semiconductor interface under a positive bias. The exemplified core-level spectra of the Al2O3/n-GaAs(001)-2 × 4 and the Al2O3/n-GaAs(001)-4 × 6 interfaces exhibit remnant of pristine surface As emission, thereby causing high frequency dispersion in the accumulation region. For the p-type GaAs, electrons under a negatively biased condition are expelled from the interface, thereby avoiding becoming trapped.

  14. Substance P enhances the activation of AMPK and cellular lipid accumulation in 3T3‑L1 cells in response to high levels of glucose.

    PubMed

    Dubon, Maria Jose; Byeon, Yeji; Park, Ki-Sook

    2015-12-01

    The rescue of glucose tolerance and insulin‑sensitivity in peripheral tissues, including adipose tissue, is essential in therapeutic strategies for diabetes. The present study demonstrated that substance P (SP) increases the accumulation of lipids in 3T3‑L1 cells during their differentiation into adipocytes in response to a high concentration of glucose. SP reciprocally regulated the activities of AMP‑activated protein kinase (AMPK) and Akt: SP enhanced the activation of AMPK, although the activity of Akt was downregulated. Notably, SP induced an increase in the expression level of glucose transporter 4 in the 3T3‑L1 adipocytes. Therefore, it is possible that SP leads to an increase in glucose uptake and the accumulation of lipids in adipocytes, and may contribute towards the rescue of insulin‑sensitivity in diabetes.

  15. Electric-field induced spin accumulation in the Landau level states of topological insulator thin films

    NASA Astrophysics Data System (ADS)

    Siu, Zhuo Bin; Chowdhury, Debashree; Basu, Banasri; Jalil, Mansoor B. A.

    2017-08-01

    A topological insulator (TI) thin film differs from the more typically studied thick TI system in that the former has both a top and a bottom surface where the states localized at both surfaces can couple to one other across the finite thickness. An out-of-plane magnetic field leads to the formation of discrete Landau level states in the system, whereas an in-plane magnetization breaks the angular momentum symmetry of the system. In this work, we study the spin accumulation induced by the application of an in-plane electric field to the TI thin film system where the Landau level states and inter-surface coupling are simultaneously present. We show, via Kubo formula calculations, that the in-plane spin accumulation perpendicular to the magnetization due to the electric field vanishes for a TI thin film with symmetric top and bottom surfaces. A finite in-plane spin accumulation perpendicular to both the electric field and magnetization emerges upon applying either a differential magnetization coupling or a potential difference between the two film surfaces. This spin accumulation results from the breaking of the antisymmetry of the spin accumulation around the k-space equal-energy contours.

  16. Accumulation of subcutaneous fat, but not visceral fat, is a predictor of adiponectin levels in preterm infants at term-equivalent age.

    PubMed

    Nakano, Yuya; Itabashi, Kazuo; Sakurai, Motoichiro; Aizawa, Madoka; Dobashi, Kazushige; Mizuno, Katsumi

    2014-05-01

    Preterm infants have altered fat tissue development, including a higher percentage of fat mass and increased volume of visceral fat. They also have altered adiponectin levels, including a lower ratio of high-molecular-weight adiponectin (HMW-Ad) to total adiponectin (T-Ad) at term-equivalent age, compared with term infants. The objective of this study was to investigate the association between adiponectin levels and fat tissue accumulation or distribution in preterm infants at term-equivalent age. Cross-sectional clinical study. Study subjects were 53 preterm infants born at ≤34weeks gestation with a mean birth weight of 1592g. Serum levels of T-Ad and HMW-Ad were measured and a computed tomography (CT) scan was performed at the level of the umbilicus at term-equivalent age to analyze how fat tissue accumulation or distribution was correlated with adiponectin levels. T-Ad (r=0.315, p=0.022) and HMW-Ad levels (r=0.338, p=0.013) were positively associated with subcutaneous fat area evaluated by performing CT scan at term-equivalent age, but were not associated with visceral fat area in simple regression analyses. In addition, T-Ad (β=0.487, p=0.003) and HMW-Ad levels (β=0.602, p<0.001) were positively associated with subcutaneous fat tissue area, but they were not associated with visceral fat area also in multiple regression analyses. Subcutaneous fat accumulation contributes to increased levels of T-Ad and HMW-Ad, while visceral fat accumulation does not influence adiponectin levels in preterm infants at term-equivalent age. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Accumulate repeat accumulate codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

  18. The effects of moderately high temperature on zeaxanthin accumulation and decay.

    PubMed

    Zhang, Ru; Kramer, David M; Cruz, Jeffrey A; Struck, Kimberly R; Sharkey, Thomas D

    2011-09-01

    Moderately high temperature reduces photosynthetic capacities of leaves with large effects on thylakoid reactions of photosynthesis, including xanthophyll conversion in the lipid phase of the thylakoid membrane. In previous studies, we have found that leaf temperature of 40°C increased zeaxanthin accumulation in dark-adapted, intact tobacco leaves following a brief illumination, but did not change the amount of zeaxanthin in light-adatped leaves. To investigate heat effects on zeaxanthin accumulation and decay, zeaxanthin level was monitored optically in dark-adapted, intact tobacco and Arabidopsis thaliana leaves at either 23 or 40°C under 45-min illumination. Heated leaves had more zeaxanthin following 3-min light but had less or comparable amounts of zeaxanthin by the end of 45 min of illumination. Zeaxanthin accumulated faster at light initiation and decayed faster upon darkening in leaves at 40°C than leaves at 23°C, indicating that heat increased the activities of both violaxanthin de-epoxidase (VDE) and zeaxanthin epoxidase (ZE). In addition, our optical measurement demonstrated in vivo that weak light enhances zeaxanthin decay relative to darkness in intact leaves of tobacco and Arabidopsis, confirming previous observations in isolated spinach chloroplasts. However, the maximum rate of decay is similar for weak light and darkness, and we used the maximum rate of decay following darkness as a measure of the rate of ZE during steady-state light. A simulation indicated that high temperature should cause a large shift in the pH dependence of the amount of zeaxanthin in leaves because of differential effects on VDE and ZE. This allows for the reduction in ΔpH caused by heat to be offset by increased VDE activity relative to ZE.

  19. The Mechanism of Starch Over-Accumulation in Chlamydomonas reinhardtii High-Starch Mutants Identified by Comparative Transcriptome Analysis

    PubMed Central

    Koo, Kwang M.; Jung, Sera; Lee, Beom S.; Kim, Jin-Baek; Jo, Yeong D.; Choi, Hong-Il; Kang, Si-Yong; Chung, Gook-H.; Jeong, Won-Joong; Ahn, Joon-Woo

    2017-01-01

    The focus of this study was the mechanism of starch accumulation in Chlamydomonas reinhardtii high-starch mutants. Three C. reinhardtii mutants showing high-starch content were generated using gamma irradiation. When grown under nitrogen-deficient conditions, these mutants had more than twice as much starch than a wild-type control. The mechanism of starch over-accumulation in these mutants was studied with comparative transcriptome analysis. In all mutants, induction of phosphoglucomutase 1 (PGM1) expression was detected; PGM1 catalyzes the inter-conversion of glucose 1-phosphate and glucose 6-phosphate in both starch biosynthetic and glycolytic pathway. Interestingly, transcript levels of phosphoglucose isomerase 1 (PGI1), fructose 1,6-bisphosphate aldolase 1 and 2 (FBA1 and FBA2) were down-regulated in all mutants; PGI1, FBA1, and FBA2 act on downstream of glucose 6-phosphate conversion in glycolytic pathway. Therefore, down-regulations of PGI1, FBA1, and FBA2 may lead to accumulation of upstream metabolites, notably glucose 6-phosphate, resulting in induction of PGM1 expression through feed-forward regulation and that PGM1 overexpression caused starch over-accumulation in mutants. These results suggest that PGI1, FBA1, FBA2, and PGM1 correlate with each other in terms of coordinated transcriptional regulation and play central roles for starch over-accumulation in C. reinhardtii. PMID:28588557

  20. High Sucrose Intake Ameliorates the Accumulation of Hepatic Triacylglycerol Promoted by Restraint Stress in Young Rats.

    PubMed

    Corona-Pérez, Adriana; Díaz-Muñoz, Mauricio; Rodríguez, Ida Soto; Cuevas, Estela; Martínez-Gómez, Margarita; Castelán, Francisco; Rodríguez-Antolín, Jorge; Nicolás-Toledo, Leticia

    2015-11-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder. Stress promotes the onset of the NAFLD with a concomitant increment in the activity of the hepatic 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1). However, the interaction between the stress and a carbohydrate-enriched diet for the development of NAFLD in young animals is unknown. In the present study, we evaluated the impact of chronic stress on the hepatic triacylglycerol level of young rats fed or not with a high sucrose-diet. For doing this, 21-day old male Wistar rats were allocated into 4 groups: control (C), chronic restraint stress (St), high-sucrose diet (S30), and chronic restraint stress plus a 30 % sucrose diet (St + S30). Chronic restraint stress consisted of 1-hour daily session, 5 days per week and for 4 weeks. Rats were fed with a standard chow and tap water (C group) or 30 % sucrose diluted in water (S30 group). The St + S30 groups consumed less solid food but had an elevated visceral fat accumulation in comparison with the St group. The St group showed a high level of serum corticosterone and a high activity of the hepatic 11β-HSD-1 concomitantly to the augmentation of hepatic steatosis signs, a high hepatic triacylglycerol content, and hepatic oxidative stress. Conversely, the high-sucrose intake in stressed rats (St + S30 group) reduced the hepatic 11β-HSD-1 activity, the level of serum corticosterone, and the hepatic triacylglycerol content. Present findings show that a high-sucrose diet ameliorates the triacylglycerol accumulation in liver promoted by the restraint stress in young male rats.

  1. [Characteristics of dry matter production and nitrogen accumulation in barley genotypes with high nitrogen utilization efficiency].

    PubMed

    Huang, Yi; Li, Ting-Xuan; Zhang, Xi-Zhou; Ji, Lin

    2014-07-01

    A pot experiment was conducted under low (125 mg x kg-1) and normal (250 mg x kg(-1)) nitrogen treatments. The nitrogen uptake and utilization efficiency of 22 barley cultivars were investigated, and the characteristics of dry matter production and nitrogen accumulation in barley were analyzed. The results showed that nitrogen uptake and utilization efficiency were different for barley under two nitrogen levels. The maximal values of grain yield, nitrogen utilization efficiency for grain and nitrogen harvest index were 2.87, 2.91 and 2.47 times as those of the lowest under the low nitrogen treatment. Grain yield and nitrogen utilization efficiency for grain and nitrogen harvest index of barley genotype with high nitrogen utilization efficiency were significantly greater than low nitrogen utilization efficiency, and the parameters of high nitrogen utilization efficiency genotype were 82.1%, 61.5% and 50.5% higher than low nitrogen utilization efficiency genotype under the low nitrogen treatment. Dry matter mass and nitrogen utilization of high nitrogen utilization efficiency was significantly higher than those of low nitrogen utilization efficiency. A peak of dry matter mass of high nitrogen utilization efficiency occurred during jointing to heading stage, while that of nitrogen accumulation appeared before jointing. Under the low nitrogen treatment, dry matter mass of DH61 and DH121+ was 34.4% and 38.3%, and nitrogen accumulation was 54. 8% and 58.0% higher than DH80, respectively. Dry matter mass and nitrogen accumulation seriously affected yield before jointing stage, and the contribution rates were 47.9% and 54.7% respectively under the low nitrogen treatment. The effect of dry matter and nitrogen accumulation on nitrogen utilization efficiency for grain was the largest during heading to mature stages, followed by sowing to jointing stages, with the contribution rate being 29.5% and 48.7%, 29.0% and 15.8%, respectively. In conclusion, barley genotype with high

  2. Accumulation effects in modulation spectroscopy with high-repetition-rate pulses: Recursive solution of optical Bloch equations

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir Al.; Pullerits, Tõnu

    2017-10-01

    Application of the phase-modulated pulsed light for advance spectroscopic measurements is the area of growing interest. The phase modulation of the light causes modulation of the signal. Separation of the spectral components of the modulations allows to distinguish the contributions of various interaction pathways. The lasers with high repetition rate used in such experiments can lead to appearance of the accumulation effects, which become especially pronounced in systems with long-living excited states. Recently it was shown that such accumulation effects can be used to evaluate parameters of the dynamical processes in the material. In this work we demonstrate that the accumulation effects are also important in the quantum characteristics measurements provided by modulation spectroscopy. In particular, we consider a model of quantum two-level system driven by a train of phase-modulated light pulses, organized in analogy with the two-dimensional spectroscopy experiments. We evaluate the harmonics' amplitudes in the fluorescent signal and calculate corrections appearing from the accumulation effects. We show that the corrections can be significant and have to be taken into account at analysis of experimental data.

  3. Effects of Enzymatically Synthesized Glycogen and Exercise on Abdominal Fat Accumulation in High-Fat Diet-Fed Mice.

    PubMed

    Tamura, Shohei; Honda, Kazuhisa; Morinaga, Ryoji; Saneyasu, Takaoki; Kamisoyama, Hiroshi

    2017-01-01

    The combination of diet and exercise is the first choice for the treatment of obesity and metabolic syndrome. We previously reported that enzymatically synthesized glycogen (ESG) suppresses abdominal fat accumulation in obese rats. However, the effect of the combination of ESG and exercise on abdominal fat accumulation has not yet been investigated. Our goal in this study was therefore to evaluate the effects of dietary ESG and its combination with exercise on abdominal fat accumulation in high-fat diet (HFD)-fed mice. Male ICR mice were assigned to four groups: HFD, HFD containing 20% ESG, HFD with exercise, HFD containing 20% ESG with exercise. Treadmill exercise was performed for 3 wk (25 m/min, 30 min/d, 3 d/wk) after 5-d adaption to running at that speed. Both ESG and exercise significantly reduced the weights of abdominal adipose tissues. In addition, the combination of ESG and exercise significantly suppressed abdominal fat accumulation, suggesting that ESG and exercise showed an additive effect. Exercise significantly increased the mRNA levels of lipid metabolism-related genes such as lipoprotein lipase, peroxisome proliferator-activated receptor delta; factor-delta (PPARδ), carnitin palmitoyltransferase b, adipose triglyceride lipase (ATGL), and uncoupling protein-3 in the gastrocnemius muscle. On the other hand, dietary ESG significantly decreased the mRNA levels of PPARδ and ATGL in the gastrocnemius muscle. These results suggest that the combined treatment of ESG and exercise effectively suppresses abdominal fat accumulation in HFD-fed mice by different mechanisms.

  4. Transcript levels, alternative splicing and proteolytic cleavage of TFIIIA control 5S rRNA accumulation during Arabidopsis thaliana development.

    PubMed

    Layat, Elodie; Cotterell, Sylviane; Vaillant, Isabelle; Yukawa, Yasushi; Tutois, Sylvie; Tourmente, Sylvette

    2012-07-01

    Ribosome biogenesis is critical for eukaryotic cells and requires coordinated synthesis of the protein and rRNA moieties of the ribosome, which are therefore highly regulated. 5S ribosomal RNA, an essential component of the large ribosomal subunit, is transcribed by RNA polymerase III and specifically requires transcription factor IIIA (TFIIIA). To obtain insight into the regulation of 5S rRNA transcription, we have investigated the expression of 5S rRNA and the exon-skipped (ES) and exon-including (EI) TFIIIA transcripts, two transcript isoforms that result from alternative splicing of the TFIIIA gene, and TFIIIA protein amounts with respect to requirements for 5S rRNA during development. We show that 5S rRNA quantities are regulated through distinct but complementary mechanisms operating through transcriptional and post-transcriptional control of TFIIIA transcripts as well as at the post-translational level through proteolytic cleavage of the TFIIIA protein. During the reproductive phase, high expression of the TFIIIA gene together with low proteolytic cleavage contributes to accumulation of functional, full-length TFIIIA protein, and results in 5S rRNA accumulation in the seed. In contrast, just after germination, the levels of TFIIIA-encoding transcripts are low and stable. Full-length TFIIIA protein is undetectable, and the level of 5S rRNA stored in the embryo progressively decreases. After day 4, in correlation with the reorganization of 5S rDNA chromatin to a mature state, full-length TFIIIA protein with transcriptional activity accumulates and permits de novo transcription of 5S rRNA. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  5. Metabolic shift of polyphosphate-accumulating organisms with different levels of polyphosphate storage.

    PubMed

    Acevedo, B; Oehmen, A; Carvalho, G; Seco, A; Borrás, L; Barat, R

    2012-04-15

    Previous studies have shown that polyphosphate-accumulating organisms (PAOs) are able to behave as glycogen-accumulating organisms (GAOs) under different conditions. In this study we investigated the behavior of a culture enriched with Accumulibacter at different levels of polyphosphate (poly-P) storage. The results of stoichiometric ratios Gly(degraded)/HAc(uptake), PHB(synthesized)/HAc(uptake), PHV(synthesized)/HAc(uptake) and P(release)/HAc(uptake) confirmed a metabolic shift from PAO metabolism to GAO metabolism: PAOs with high poly-P content used the poly-P to obtain adenosine tri-phosphate (ATP), and glycogen (Gly) to obtain nicotinamide adenine dinucleotide (NADH) and some ATP. In a test where poly-P depletion was imposed on the culture, all the acetate (HAc) added in each cycle was transformed into polyhydroxyalkanoate (PHA) despite the decrease of poly-P inside the cells. This led to an increase of the Gly(degraded)/HAc(uptake) ratio that resulted from a shift towards the glycolytic pathway in order to compensate for the lack of ATP formed from poly-P hydrolysis. The shift from PAO to GAO metabolism was also reflected in the change in the PHA composition as the poly-P availability decreased, suggesting that polyhydroxyvalerate (PHV) is obtained due to the consumption of excess reducing equivalents to balance the internal NADH, similarly to GAO metabolism. Fluorescence in situ hybridization analysis showed a significant PAO population change from Type I to Type II Accumulibacter as the poly-P availability decreased in short term experiments. This work suggests that poly-P storage levels and GAO-like metabolism are important factors affecting the competition between different PAO Types in enhanced biological phosphorus removal systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. High salinity leads to accumulation of soil organic carbon in mangrove soil.

    PubMed

    Kida, Morimaru; Tomotsune, Mitsutoshi; Iimura, Yasuo; Kinjo, Kazutoshi; Ohtsuka, Toshiyuki; Fujitake, Nobuhide

    2017-06-01

    Although mangrove forests are one of the most well-known soil organic carbon (SOC) sinks, the mechanism underlying SOC accumulation is relatively unknown. High net primary production (NPP) along with the typical bottom-heavy biomass allocation and low soil respiration (SR) have been considered to be responsible for SOC accumulation. However, an emerging paradigm postulates that SR is severely underestimated because of the leakage of dissolved inorganic carbon (DIC) in groundwater. Here we propose a simple yet unique mechanism for SOC accumulation in mangrove soils. We conducted sequential extraction of water extractable organic matter (WEOM) from mangrove soils using ultrapure water and artificial seawater, respectively. A sharp increase in humic substances (HS) concentration was observed only in the case of ultrapure water, along with a decline in salinity. Extracted WEOM was colloidal, and ≤70% of it re-precipitated by the addition of artificial seawater. These results strongly suggest that HS is selectively flocculated and maintained in the mangrove soils because of high salinity. Because sea salts are a characteristic of any mangrove forest, high salinity may be one of mechanisms underlying SOC accumulation in mangrove soils. Copyright © 2017. Published by Elsevier Ltd.

  7. Accumulated source imaging of brain activity with both low and high-frequency neuromagnetic signals

    PubMed Central

    Xiang, Jing; Luo, Qian; Kotecha, Rupesh; Korman, Abraham; Zhang, Fawen; Luo, Huan; Fujiwara, Hisako; Hemasilpin, Nat; Rose, Douglas F.

    2014-01-01

    Recent studies have revealed the importance of high-frequency brain signals (>70 Hz). One challenge of high-frequency signal analysis is that the size of time-frequency representation of high-frequency brain signals could be larger than 1 terabytes (TB), which is beyond the upper limits of a typical computer workstation's memory (<196 GB). The aim of the present study is to develop a new method to provide greater sensitivity in detecting high-frequency magnetoencephalography (MEG) signals in a single automated and versatile interface, rather than the more traditional, time-intensive visual inspection methods, which may take up to several days. To address the aim, we developed a new method, accumulated source imaging, defined as the volumetric summation of source activity over a period of time. This method analyzes signals in both low- (1~70 Hz) and high-frequency (70~200 Hz) ranges at source levels. To extract meaningful information from MEG signals at sensor space, the signals were decomposed to channel-cross-channel matrix (CxC) representing the spatiotemporal patterns of every possible sensor-pair. A new algorithm was developed and tested by calculating the optimal CxC and source location-orientation weights for volumetric source imaging, thereby minimizing multi-source interference and reducing computational cost. The new method was implemented in C/C++ and tested with MEG data recorded from clinical epilepsy patients. The results of experimental data demonstrated that accumulated source imaging could effectively summarize and visualize MEG recordings within 12.7 h by using approximately 10 GB of computer memory. In contrast to the conventional method of visually identifying multi-frequency epileptic activities that traditionally took 2–3 days and used 1–2 TB storage, the new approach can quantify epileptic abnormalities in both low- and high-frequency ranges at source levels, using much less time and computer memory. PMID:24904402

  8. Accumulated source imaging of brain activity with both low and high-frequency neuromagnetic signals.

    PubMed

    Xiang, Jing; Luo, Qian; Kotecha, Rupesh; Korman, Abraham; Zhang, Fawen; Luo, Huan; Fujiwara, Hisako; Hemasilpin, Nat; Rose, Douglas F

    2014-01-01

    Recent studies have revealed the importance of high-frequency brain signals (>70 Hz). One challenge of high-frequency signal analysis is that the size of time-frequency representation of high-frequency brain signals could be larger than 1 terabytes (TB), which is beyond the upper limits of a typical computer workstation's memory (<196 GB). The aim of the present study is to develop a new method to provide greater sensitivity in detecting high-frequency magnetoencephalography (MEG) signals in a single automated and versatile interface, rather than the more traditional, time-intensive visual inspection methods, which may take up to several days. To address the aim, we developed a new method, accumulated source imaging, defined as the volumetric summation of source activity over a period of time. This method analyzes signals in both low- (1~70 Hz) and high-frequency (70~200 Hz) ranges at source levels. To extract meaningful information from MEG signals at sensor space, the signals were decomposed to channel-cross-channel matrix (CxC) representing the spatiotemporal patterns of every possible sensor-pair. A new algorithm was developed and tested by calculating the optimal CxC and source location-orientation weights for volumetric source imaging, thereby minimizing multi-source interference and reducing computational cost. The new method was implemented in C/C++ and tested with MEG data recorded from clinical epilepsy patients. The results of experimental data demonstrated that accumulated source imaging could effectively summarize and visualize MEG recordings within 12.7 h by using approximately 10 GB of computer memory. In contrast to the conventional method of visually identifying multi-frequency epileptic activities that traditionally took 2-3 days and used 1-2 TB storage, the new approach can quantify epileptic abnormalities in both low- and high-frequency ranges at source levels, using much less time and computer memory.

  9. Predictive modelling of JT-60SA high-beta steady-state plasma with impurity accumulation

    NASA Astrophysics Data System (ADS)

    Hayashi, N.; Hoshino, K.; Honda, M.; Ide, S.

    2018-06-01

    The integrated modelling code TOPICS has been extended to include core impurity transport, and applied to predictive modelling of JT-60SA high-beta steady-state plasma with the accumulation of impurity seeded to reduce the divertor heat load. In the modelling, models and conditions are selected for a conservative prediction, which considers a lower bound of plasma performance with the maximum accumulation of impurity. The conservative prediction shows the compatibility of impurity seeding with core plasma with high-beta (β N  >  3.5) and full current drive conditions, i.e. when Ar seeding reduces the divertor heat load below 10 MW m‑2, its accumulation in the core is so moderate that the core plasma performance can be recovered by additional heating within the machine capability to compensate for Ar radiation. Due to the strong dependence of accumulation on the pedestal density gradient, high separatrix density is important for the low accumulation as well as the low divertor heat load. The conservative prediction also shows that JT-60SA has enough capability to explore the divertor heat load control by impurity seeding in high-beta steady-state plasmas.

  10. High-Affinity Accumulation of Chloroquine by Mouse Erythrocytes Infected with Plasmodium berghei

    PubMed Central

    Fitch, Coy D.; Yunis, Norman G.; Chevli, Rekha; Gonzalez, Yolanda

    1974-01-01

    Washed erythrocytes infected with chloroquine-susceptible (CS) or with chloroquine-resistant (CR) P. berghei were used in model systems in vitro to study the accumulation of chloroquine with high affinity. The CS model could achieve distribution ratios (chloroquine in cells: chloroquine in medium) of 100 in the absence of substrate. 200—300 in the presence of 10 mM pyruvate or lactate, and over 600 in the presence of 1 mM glucose or glycerol. In comparable studies of the CR model, the distribution ratios were 100 in the absence of substrate and 300 or less in the presence of glucose or glycerol. The presence of lactate stimulated chloroquine accumulation in the CR model, whereas the presence of pyruvate did not. Lactate production from glucose and glycerol was undiminished in the CR model, and ATP concentrations were higher than in the CS model. Cold, iodoacetate, 2,4-dinitrophenol, or decreasing pH inhibited chloroquine accumulation in both models. These findings demonstrate substrate involvement in the accumulation of chloroquine with high affinity. In studies of the CS model, certain compounds competitively inhibited chloroquine accumulation, while others did not. This finding is attributable to a specific receptor that imposes structural constraints on the process of accumulation. For chloroquine analogues, the position and length of the side chain, the terminal nitrogen atom of the side chain, and the nitrogen atom in the quinoline ring are important determinants of binding to this receptor. PMID:4600044

  11. Insights about the interaction between sea-level rise, sediment accumulation and subsidence: the example of the Ganges Brahmaputra Delta during the Holocene

    NASA Astrophysics Data System (ADS)

    Grall, C.; Steckler, M. S.; Pickering, J.; Goodbred, S. L., Jr.; Sincavage, R.; Hossain, S.; Paola, C.; Spiess, V.

    2016-12-01

    The hazard associated with sea-level rise (shoreline erosion, flooding and wetlands loss) may dramatically increase when human interventions interfere with the natural responses of the coastal regions to the eustatic rise. We here provide insights about such natural processes, by documenting the manner in which subsidence, sediment input and sediment distribution interact together during the well-known Holocene eustatic rise period, in the Ganges- Brahmaputra-Meghna Delta (GBMD) in Bangladesh. The dataset combines more than 400 hand-drilled stratigraphic wells, 185 radiocarbon ages, and seismic reflection imaging data (255 km of high resolution multichannel seismic dataset), collected thanks to recent research in the BanglaPIRE project. We use two independent approaches for analyzing this broad dataset. First, we estimate the total volume of Holocene sediments in the GBMD. In doing so, we define empirical laws to build up a virtual model of sediment accumulation that takes into account the contrasts in accumulation between rivers and alluvial plains as well as the regional seaward gradient of sediment accumulation. As the evolution of river occupation over the Holocene at the regional scale is now relatively well constrained, we estimate the total volume of sediment deposited in the Delta during the Holocene. Secondly, we use detailed age-models of sediment accumulation at 92 sites (based on 185 radiocarbon ages) for distinguishing the effects of eustasy and subsidence on the sediment accumulation in the different domains of the delta (namely the tidal dominated plain and the fluvial dominated plain). Using these two independent approaches, we are able to quantify the natural subsidence and the relative distribution of subsidence. We emphasize the difference between the subsidence and the sediment accumulation, by showing that sediment accumulation is more than twice the subsidence on average during the Holocene, which allows us to quantify the increase of sediment

  12. High-level production of human interleukin-10 fusions in tobacco cell suspension cultures

    PubMed Central

    Kaldis, Angelo; Ahmad, Adil; Reid, Alexandra; McGarvey, Brian; Brandle, Jim; Ma, Shengwu; Jevnikar, Anthony; Kohalmi, Susanne E; Menassa, Rima

    2013-01-01

    The production of pharmaceutical proteins in plants has made much progress in recent years with the development of transient expression systems, transplastomic technology and humanizing glycosylation patterns in plants. However, the first therapeutic proteins approved for administration to humans and animals were made in plant cell suspensions for reasons of containment, rapid scale-up and lack of toxic contaminants. In this study, we have investigated the production of human interleukin-10 (IL-10) in tobacco BY-2 cell suspension and evaluated the effect of an elastin-like polypeptide tag (ELP) and a green fluorescent protein (GFP) tag on IL-10 accumulation. We report the highest accumulation levels of hIL-10 obtained with any stable plant expression system using the ELP fusion strategy. Although IL-10-ELP has cytokine activity, its activity is reduced compared to unfused IL-10, likely caused by interference of ELP with folding of IL-10. Green fluorescent protein has no effect on IL-10 accumulation, but examining the trafficking of IL-10-GFP over the cell culture cycle revealed fluorescence in the vacuole during the stationary phase of the culture growth cycle. Analysis of isolated vacuoles indicated that GFP alone is found in vacuoles, while the full-size fusion remains in the whole-cell extract. This indicates that GFP is cleaved off prior to its trafficking to the vacuole. On the other hand, IL-10-GFP-ELP remains mostly in the ER and accumulates to high levels. Protein bodies were observed at the end of the culture cycle and are thought to arise as a consequence of high levels of accumulation in the ER. PMID:23297698

  13. High-level accumulation of oleyl oleate in plant seed oil by abundant supply of oleic acid substrates to efficient wax ester synthesis enzymes.

    PubMed

    Yu, Dan; Hornung, Ellen; Iven, Tim; Feussner, Ivo

    2018-01-01

    Biotechnology enables the production of high-valued industrial feedstocks from plant seed oil. The plant-derived wax esters with long-chain monounsaturated acyl moieties, like oleyl oleate, have favorite properties for lubrication. For biosynthesis of wax esters using acyl-CoA substrates, expressions of a fatty acyl reductase (FAR) and a wax synthase (WS) in seeds are sufficient. For optimization of the enzymatic activity and subcellular localization of wax ester synthesis enzymes, two fusion proteins were created, which showed wax ester-forming activities in Saccharomyces cerevisiae . To promote the formation of oleyl oleate in seed oil, WSs from Acinetobactor baylyi ( Ab WSD1) and Marinobacter aquaeolei ( Ma WS2), as well as the two created fusion proteins were tested in Arabidopsis to evaluate their abilities and substrate preference for wax ester production. The tested seven enzyme combinations resulted in different yields and compositions of wax esters. Expression of a FAR of Marinobacter aquaeolei ( Ma FAR) with Ab WSD1 or Ma WS2 led to a high incorporation of C 18 substrates in wax esters. The Ma FAR/TM Mm AWAT2- Ab WSD1 combination resulted in the incorporation of more C 18:1 alcohol and C 18:0 acyl moieties into wax esters compared with Ma FAR/ Ab WSD1. The fusion protein of a WS from Simmondsia chinensis ( Sc WS) with MaFAR exhibited higher specificity toward C 20:1 substrates in preference to C 18:1 substrates. Expression of Ma FAR/ Ab WSD1 in the Arabidopsis fad2 fae1 double mutant resulted in the accumulation of oleyl oleate (18:1/18:1) in up to 62 mol% of total wax esters in seed oil, which was much higher than the 15 mol% reached by Ma FAR/ Ab WSD1 in Arabidopsis Col-0 background. In order to increase the level of oleyl oleate in seed oil of Camelina , lines expressing Ma FAR/ Sc WS were crossed with a transgenic high oleate line. The resulting plants accumulated up to >40 mg g seed -1 of wax esters, containing 27-34 mol% oleyl oleate. The

  14. Proline accumulation protects Saccharomyces cerevisiae cells in stationary phase from ethanol stress by reducing reactive oxygen species levels.

    PubMed

    Takagi, Hiroshi; Taguchi, Junpei; Kaino, Tomohiro

    2016-08-01

    During fermentation processes, Saccharomyces cerevisiae cells are exposed to multiple stresses, including a high concentration of ethanol that represents toxicity through intracellular reactive oxygen species (ROS) generation. We previously reported that proline protected yeast cells from damage caused by various stresses, such as freezing and ethanol. As an anti-oxidant, proline is suggested to scavenge intracellular ROS. In this study, we examined the role of intracellular proline during ethanol treatment in S. cerevisiae strains that accumulate different concentrations of proline. When cultured in YPD medium, there was a significant accumulation of proline in the put1 mutant strain, which is deficient in proline oxidase, in the stationary phase. Expression of the mutant PRO1 gene, which encodes the γ-glutamyl kinase variant (Asp154Asn or Ile150Thr) with desensitization to feedback inhibition by proline in the put1 mutant strain, showed a prominent increase in proline content as compared with that of the wild-type strain. The oxidation level was clearly increased in wild-type cells after exposure to ethanol, indicating that the generation of ROS occurred. Interestingly, proline accumulation significantly reduces the ROS level and increases the survival rate of yeast cells in the stationary phase under ethanol stress conditions. However, there was not a clear correlation between proline content and survival rate in yeast cells. An appropriate level of intracellular proline in yeast might be important for its stress-protective effect. Hence, the engineering of proline metabolism could be promising for breeding stress-tolerant industrial yeast strains. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Reduced circulating levels of sTWEAK are associated with NAFLD and may affect hepatocyte triglyceride accumulation.

    PubMed

    Lozano-Bartolomé, J; Llauradó, G; Rodriguez, M M; Fernandez-Real, J M; Garcia-Fontgivell, J F; Puig, J; Maymó-Masip, E; Vendrell, J; Chacón, M R

    2016-09-01

    Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and is strongly associated with obesity, dyslipidaemia and altered glucose regulation. Previous data demonstrated that low circulating levels of tumour necrosis factor weak inducer of apoptosis (sTWEAK) were associated with obesity, diabetes and insulin resistance, all traits associated with an increased risk of NALFD. Circulating sTWEAK levels are expected to be reduced in the presence of NAFLD. We aimed to explore the relationship between NAFLD and circulating sTWEAK levels in obese patients, and to evaluate the effect of sTWEAK on hepatocyte triglyceride accumulation.Design setting and patients:This is an observational case-control study performed in n=112 severely obese patients evaluated for NAFLD by abdominal ultrasound and n=32 non-obese patients without steatosis. Serum sTWEAK concentrations were measured by ELISA. Multivariable analyses were performed to determine the independent predictors of NAFLD. We analysed TWEAK and Fn14 protein expression in liver biopsies by western blotting and immunohistochemistry. An immortalized primary human hepatocyte cell line (HHL) was used to evaluate the effect of sTWEAK on triglyceride accumulation. We observed a reduction in serum circulating sTWEAK concentrations with the presence of liver steatosis. On multivariable analysis, lower sTWEAK concentrations were independently associated with the presence of NAFLD (odds ratio (OR)=0.023; 95% confidence interval: 0.001-0.579; P<0.022). In human hepatocytes, sTWEAK administration reduced fat accumulation as demonstrated by the reduction in palmitic acid-induced accumulation of triglyceride and the decreased expression of cluster of differentiation 36 (CD36) and perilipin 1 and 2 (PLIN1 and PLIN2) genes. Decreased sTWEAK concentrations are independently associated with the presence of NAFLD. This is concordant with the observation that TWEAK reduces lipid accumulation in human

  16. Glycine Betaine, Carnitine, and Choline Enhance Salinity Tolerance and Prevent the Accumulation of Sodium to a Level Inhibiting Growth of Tetragenococcus halophila

    PubMed Central

    Robert, Hervé; Le Marrec, Claire; Blanco, Carlos; Jebbar, Mohamed

    2000-01-01

    Natural-abundance 13C-nuclear magnetic resonance was used to probe the intracellular organic solute content of the moderately halophilic bacterium Tetragenococcus halophila. When grown in complex growth media supplemented or not with NaCl, T. halophila accumulates glycine betaine and carnitine. Unlike other moderate halophiles, T. halophila was not able to produce potent osmoprotectants (such as ectoines and glycine betaine) through de novo synthesis when cultured in defined medium under hyperosmotic constraint. Addition of 2 mM carnitine, glycine betaine, or choline to defined medium improved growth parameters, not only at high salinity (up to 2.5 M NaCl) but also in media lacking NaCl. These compounds were taken up when available in the surrounding medium. The transport activity occurred at low and high salinities and seems to be constitutive. Glycine betaine and carnitine were accumulated by T. halophila in an unmodified form, while exogenously provided choline led to an intracellular accumulation of glycine betaine. This is the first evidence of the existence of a choline-glycine betaine pathway in a lactic acid bacterium. An assay showed that the compatible solutes strikingly repressed the accumulation of glutamate and slightly increased the intracellular potassium level only at high salinity. Interestingly, osmoprotectant-treated cells were able to maintain the intracellular sodium concentration at a relatively constant level (200 to 300 nmol/mg [dry weight]), independent of the NaCl concentration of the medium. In contrast, in the absence of osmoprotectant, the intracellular sodium content increased sharply from 200 to 2,060 nmol/mg (dry weight) when the salinity of the medium was raised from 1 to 2 M. Indeed, the imported compatible solutes play an actual role in regulating the intracellular Na+ content and confer a much higher salt tolerance to T. halophila. PMID:10653711

  17. Cadmium Accumulation in Two Populations of Rice Frogs (Fejervarya limnocharis) Naturally Exposed to Different Environmental Cadmium Levels

    PubMed Central

    Othman, Mohd Sham; Khonsue, Wichase; Kitana, Jirarach; Thirakhupt, Kumthorn; Robson, Mark Gregory

    2014-01-01

    Contaminant accumulation analysis is important in the study of sentinels. This research determined cadmium accumulation and bioconcentration factors of whole organism, liver, kidney, ovary and testis of Fejervarya limnocharis exposed to different environmental cadmium levels. Frogs from contaminated sites had significantly higher hepatic (1.939 mg/kg), renal (7.253 mg/kg) and testicular (1.462 mg/kg) cadmium than those from the reference sites (0.205, 0.783 and 0.379 mg/kg, respectively). Cadmium accumulation was the highest during the late dry and early rainy seasons. If this species is used as a sentinel for cadmium accumulation, the utilization of its whole organism, liver, kidney and testis is appropriate. PMID:19690790

  18. Controller and interface module for the High-Speed Data Acquisition System correlator/accumulator

    NASA Technical Reports Server (NTRS)

    Brokl, S. S.

    1985-01-01

    One complex channel of the High-Speed Data Acquisition System (a subsystem used in the Goldstone solar system radar), consisting of two correlator modules and one accumulator module, is operated by the controller and interface module interfaces are provided to the VAX UNIBUS for computer control, monitor, and test of the controller and correlator/accumulator. The correlator and accumulator modules controlled by this module are the key digital signal processing elements of the Goldstone High-Speed Data Acquisition System. This fully programmable unit provides for a wide variety of correlation and filtering functions operating on a three megaword/second data flow. Data flow is to the VAX by way of the I/O port of a FPS 5210 array processor.

  19. High accumulation of anthocyanins via the ectopic expression of AtDFR confers significant salt stress tolerance in Brassica napus L.

    PubMed

    Kim, Jihye; Lee, Won Je; Vu, Tien Thanh; Jeong, Chan Young; Hong, Suk-Whan; Lee, Hojoung

    2017-08-01

    The ectopic expression of AtDFR results in increased accumulation of anthocyanins leading to enhanced salinity and drought stress tolerance in B. napus plants. Flavonoids with antioxidant effects confer many additional benefits to plants. Evidence indicates that flavonoids, including anthocyanins, protect tissues against oxidative stress from various abiotic stressors. We determined whether increases in anthocyanins increased abiotic stress tolerance in Brassica napus, because the values of B. napus L. and its cultivation area are increasing worldwide. We overexpressed Arabidopsis dihydroflavonol-4-reductase (DFR) in B. napus. Increased DFR transcript levels for AtDFR-OX B. shoots correlated with higher anthocyanin accumulation. AtDFR-OX Brassica shoots exhibited lower reactive oxygen species (ROS) accumulation than wild-type (WT) shoots under high NaCl and mannitol concentrations. This was corroborated by 3,3-diaminobenzidine staining for ROS scavenging activity in 1,1-diphenyl-2-picryl-hydrazyl assays. Shoots of the AtDFR-OX B. napus lines grown in a high salt medium exhibited enhanced salt tolerance and higher chlorophyll content than similarly grown WT plants. Our observations suggested that the AtDFR gene can be effectively manipulated to modulate salinity and drought stress tolerance by directing to high accumulation of anthocyanins in oilseed plants.

  20. Metabolic Adaptation in Transplastomic Plants Massively Accumulating Recombinant Proteins

    PubMed Central

    Bally, Julia; Job, Claudette; Belghazi, Maya; Job, Dominique

    2011-01-01

    Background Recombinant chloroplasts are endowed with an astonishing capacity to accumulate foreign proteins. However, knowledge about the impact on resident proteins of such high levels of recombinant protein accumulation is lacking. Methodology/Principal Findings Here we used proteomics to characterize tobacco (Nicotiana tabacum) plastid transformants massively accumulating a p-hydroxyphenyl pyruvate dioxygenase (HPPD) or a green fluorescent protein (GFP). While under the conditions used no obvious modifications in plant phenotype could be observed, these proteins accumulated to even higher levels than ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), the most abundant protein on the planet. This accumulation occurred at the expense of a limited number of leaf proteins including Rubisco. In particular, enzymes involved in CO2 metabolism such as nuclear-encoded plastidial Calvin cycle enzymes and mitochondrial glycine decarboxylase were found to adjust their accumulation level to these novel physiological conditions. Conclusions/Significance The results document how protein synthetic capacity is limited in plant cells. They may provide new avenues to evaluate possible bottlenecks in recombinant protein technology and to maintain plant fitness in future studies aiming at producing recombinant proteins of interest through chloroplast transformation. PMID:21966485

  1. Micronutrients-fortified rapeseed oil improves hepatic lipid accumulation and oxidative stress in rats fed a high-fat diet

    PubMed Central

    2013-01-01

    Intake of high-fat diet is associated with increased fatty livers. Hepatic lipid accumulation and oxidative stress are key pathophysiological mechanisms in this disease. Micronutrients polyphenols, tocopherols and phytosterols in rapeseed exert potential benefit to hepatoprotection, but most of these micronutrients are removed by the traditional refining process. The purpose of the present study was to determine whether rapeseed oil fortified with these micronutrients can decrease hepatic lipid accumulation and oxidative stress induced by high-fat diet. Sprague–Dawley rats received rodent diet contained 20% fat whose source was refined rapeseed oil (RRO) or fortified RRO with low, middle and high quantities of these micronutrients for 10 weeks. Intake of RRO caused a remarkable hepatic steatosis. Micronutrients supplementation was effective in reducing steatosis as well as total triglyceride and total cholesterol contents in liver. These micronutrients also significantly increased hepatic antioxidant defense capacities, as evaluated by the significant elevation in the activities of SOD and GPx as well as the level of GSH, and the significant decline in lipid peroxidation. These findings suggest that rapeseed oil fortified with micronutrients polyphenols, tocopherols and phytosterols may contribute to prevent fatty livers such as nonalcoholic fatty liver disease by ameliorating hepatic lipid accumulation and oxidative stress. PMID:23510587

  2. Cadmium tolerance and accumulation in cultivars of a high-biomass tropical tree (Averrhoa carambola) and its potential for phytoextraction.

    PubMed

    Li, J T; Liao, B; Lan, C Y; Ye, Z H; Baker, A J M; Shu, W S

    2010-01-01

    Averrhoa carambola is a high-biomass tropical tree that has been identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A. carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A. carambola varied greatly among sites and cultivars. The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A. carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0.3 to 51.8% of the total Cd content in the top 20-cm soil layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in soils with 6 and 12 mg Cd kg(-1) were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment. Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cd, compared with the control species. The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A. carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars.

  3. An E8 promoter-HSP terminator cassette promotes the high-level accumulation of recombinant protein predominantly in transgenic tomato fruits: a case study of miraculin.

    PubMed

    Kurokawa, Natsuko; Hirai, Tadayoshi; Takayama, Mariko; Hiwasa-Tanase, Kyoko; Ezura, Hiroshi

    2013-04-01

    The E8 promoter-HSP terminator expression cassette is a powerful tool for increasing the accumulation of recombinant protein in a ripening tomato fruit. Strong, tissue-specific transgene expression is a desirable feature in transgenic plants to allow the production of variable recombinant proteins. The expression vector is a key tool to control the expression level and site of transgene and recombinant protein expression in transgenic plants. The combination of the E8 promoter, a fruit-ripening specific promoter, and a heat shock protein (HSP) terminator, derived from heat shock protein 18.2 of Arabidopsis thaliana, produces the strong and fruit-specific accumulation of recombinant miraculin in transgenic tomato. Miraculin gene expression was driven by an E8 promoter and HSP terminator cassette (E8-MIR-HSP) in transgenic tomato plants, and the miraculin concentration was the highest in the ripening fruits, representing 30-630 μg miraculin of the gram fresh weight. The highest level of miraculin concentration among the transgenic tomato plant lines containing the E8-MIR-HSP cassette was approximately four times higher than those observed in a previous study using a constitutive 35S promoter and NOS terminator cassette (Hiwasa-Tanase et al. in Plant Cell Rep 30:113-124, 2011). These results demonstrate that the combination of the E8 promoter and HSP terminator cassette is a useful tool to increase markedly the accumulation of recombinant proteins in a ripening fruit-specific manner.

  4. Effects of salicylic acid on thermotolerance and cardenolide accumulation under high temperature stress in Digitalis trojana Ivanina.

    PubMed

    Cingoz, Gunce Sahin; Gurel, Ekrem

    2016-08-01

    Long periods of high temperature or transitory increased temperature, a widespread agricultural problem, may lead to a drastic reduction in economic yield, affecting plant growth and development in many areas of the world. Heat stress causes many anatomical and physiological changes in plants. Its unfavorable effects can be alleviated by thermotolerance induced by exogenous application of plant growth regulators and osmoprotectants or by gradual application of temperature stress. Digitalis trojana Ivanina is an important medicinal plant species well known mainly for its cardenolides. The production of cardenolides via traditional agriculture is commercially inadequate. In this study, elicitation strategies were employed for improving crop thermotolerance and accumulation of cardenolides. For these purposes, the effects of salicylic acid (SA) and/or high temperature treatments in inducing cardenolide accumulation and thermotolerance were tested in callus cultures of D. trojana. Considerable increases in the production of cardenolides (up to 472.28 μg.g(-1) dry weight, dw) and induction of thermotolerance capacity were observed when callus cultures were exposed to high temperature for 2 h after pretreating with SA. High temperature treatments (2 h and 4 h) caused a marked reduction in superoxide dismutase (SOD; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6) activities, while SA pretreatment increased their activities. High temperature and/or SA appeared to increase the levels of proline, total phenolic, and flavonoid content. Elevated phenolic accumulation could be associated with increased stress protection. These results indicated that SA treatments induced synthesis of antioxidants and cardenolides, which may play a significant role in resistance to high temperature stress. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. High levels of heavy metal accumulation in dental calculus of smokers: a pilot inductively coupled plasma mass spectrometry study.

    PubMed

    Yaprak, E; Yolcubal, I; Sinanoğlu, A; Doğrul-Demiray, A; Guzeldemir-Akcakanat, E; Marakoğlu, I

    2017-02-01

    Various trace elements, including toxic heavy metals, may exist in dental calculus. However, the effect of environmental factors on heavy metal composition of dental calculus is unknown. Smoking is a major environmental source for chronic toxic heavy metal exposition. The aim of this study is to compare toxic heavy metal accumulation levels in supragingival dental calculus of smokers and non-smokers. A total of 29 supragingival dental calculus samples were obtained from non-smoker (n = 14) and smoker (n = 15) individuals. Subjects with a probability of occupational exposure were excluded from the study. Samples were analyzed by inductively coupled plasma mass spectrometry in terms of 26 metals and metalloids, including toxic heavy metals. Toxic heavy metals, arsenic (p < 0.05), cadmium (p < 0.05), lead (p < 0.01), manganese (p < 0.01) and vanadium (p < 0.01) levels were significantly higher in smokers than non-smokers. The levels of other examined elements were similar in both groups (p > 0.05). Within the limitations of this study, it can be concluded that the elementary composition of dental calculus may be affected by environmental factors such as tobacco smoke. Therefore, dental calculus may be utilized as a non-invasive diagnostic biological material for monitoring chronic oral heavy metal exposition. However, further studies are required to evaluate its diagnostic potential. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Persistent high temperature and low precipitation reduce peat carbon accumulation.

    PubMed

    Bragazza, Luca; Buttler, Alexandre; Robroek, Bjorn J M; Albrecht, Remy; Zaccone, Claudio; Jassey, Vincent E J; Signarbieux, Constant

    2016-12-01

    Extreme climate events are predicted to become more frequent and intense. Their ecological impacts, particularly on carbon cycling, can differ in relation to ecosystem sensitivity. Peatlands, being characterized by peat accumulation under waterlogged conditions, can be particularly sensitive to climate extremes if the climate event increases soil oxygenation. However, a mechanistic understanding of peatland responses to persistent climate extremes is still lacking, particularly in terms of aboveground-belowground feedback. Here, we present the results of a transplantation experiment of peat mesocosms from high to low altitude in order to simulate, during 3 years, a mean annual temperature c. 5 °C higher and a mean annual precipitation c. 60% lower. Specifically, we aim at understanding the intensity of changes for a set of biogeochemical processes and their feedback on carbon accumulation. In the transplanted mesocosms, plant productivity showed a species-specific response depending on plant growth forms, with a significant decrease (c. 60%) in peat moss productivity. Soil respiration almost doubled and Q 10 halved in the transplanted mesocosms in combination with an increase in activity of soil enzymes. Spectroscopic characterization of peat chemistry in the transplanted mesocosms confirmed the deepening of soil oxygenation which, in turn, stimulated microbial decomposition. After 3 years, soil carbon stock increased only in the control mesocosms whereas a reduction in mean annual carbon accumulation of c. 30% was observed in the transplanted mesocosms. Based on the above information, a structural equation model was built to provide a mechanistic understanding of the causal connections between peat moisture, vegetation response, soil respiration and carbon accumulation. This study identifies, in the feedback between plant and microbial responses, the primary pathways explaining the reduction in carbon accumulation in response to recurring climate extremes in

  7. Elevated TMEM106B levels exaggerate lipofuscin accumulation and lysosomal dysfunction in aged mice with progranulin deficiency.

    PubMed

    Zhou, Xiaolai; Sun, Lirong; Brady, Owen Adam; Murphy, Kira A; Hu, Fenghua

    2017-01-26

    Mutations resulting in haploinsufficiency of progranulin (PGRN) cause frontotemporal lobar degeneration with TDP-43-positive inclusions (FTLD-TDP), a devastating neurodegenerative disease. Accumulating evidence suggest a crucial role of progranulin in maintaining proper lysosomal function during aging. TMEM106B has been identified as a risk factor for frontotemporal lobar degeneration with progranulin mutations and elevated mRNA and protein levels of TMEM106B are associated with increased risk for frontotemporal lobar degeneration. Increased levels of TMEM106B alter lysosomal morphology and interfere with lysosomal degradation. However, how progranulin and TMEM106B interact to regulate lysosomal function and frontotemporal lobar degeneration (FTLD) disease progression is still unclear. Here we report that progranulin deficiency leads to increased TMEM106B protein levels in the mouse cortex with aging. To mimic elevated levels of TMEM106B in frontotemporal lobar degeneration (FTLD) cases, we generated transgenic mice expressing TMEM106B under the neuronal specific promoter, CamKII. Surprisingly, we found that the total protein levels of TMEM106B are not altered despite the expression of the TMEM106B transgene at mRNA and protein levels, suggesting a tight regulation of TMEM106B protein levels in the mouse brain. However, progranulin deficiency results in accumulation of TMEM106B protein from the transgene expression during aging, which is accompanied by exaggerated lysosomal abnormalities and increased lipofuscin accumulation. In summary, our mouse model nicely recapitulates the interaction between progranulin and TMEM106B in human patients and supports a critical role of lysosomal dysfunction in the frontotemporal lobar degeneration (FTLD) disease progression.

  8. Optimized Rapeseed Oils Rich in Endogenous Micronutrients Protect High Fat Diet Fed Rats from Hepatic Lipid Accumulation and Oxidative Stress

    PubMed Central

    Xu, Jiqu; Liu, Xiaoli; Gao, Hui; Chen, Chang; Deng, Qianchun; Huang, Qingde; Ma, Zhonghua; Huang, Fenghong

    2015-01-01

    Micronutrients in rapeseed exert a potential benefit to hepatoprotection, but most of them are lost during the conventional refining processing. Thus some processing technologies have been optimized to improve micronutrient retention in oil. The aim of this study is to assess whether optimized rapeseed oils (OROs) have positive effects on hepatic lipid accumulation and oxidative stress induced by a high-fat diet. Methods: Rats received experiment diets containing 20% fat and refined rapeseed oil or OROs obtained with various processing technologies as lipid source. After 10 weeks of treatment, liver was assayed for lipid accumulation and oxidative stress. Results: All OROs reduced hepatic triglyceride contents. Microwave pretreatment-cold pressing oil (MPCPO) which had the highest micronutrients contents also reduced hepatic cholesterol level. MPCPO significantly decreased hepatic sterol regulatory element-binding transcription factor 1 (SREBP1) but increased peroxisome proliferator activated receptor α (PPARα) expressions, and as a result, MPCPO significantly suppressed acetyl CoA carboxylase and induced carnitine palmitoyl transferase-1 and acyl CoA oxidase expression. Hepatic catalase (CAT) and glutathione peroxidase (GPx) activities as well as reduced glutathione (GSH) contents remarkably increased and lipid peroxidation levels decreased in parallel with the increase of micronutrients. Conclusion: OROs had the ability to reduce excessive hepatic fat accumulation and oxidative stress, which indicated that OROs might contribute to ameliorating nonalcoholic fatty liver induced by high-fat diet. PMID:26473919

  9. 5-Aminolevulinic Acid Accumulation in a Cerebral Infarction Mimicking High-Grade Glioma.

    PubMed

    Behling, Felix; Hennersdorf, Florian; Bornemann, Antje; Tatagiba, Marcos; Skardelly, Marco

    2016-08-01

    5-Aminolevulinic acid (5-ALA) has become an integral part in the neurosurgical treatment of malignant glioma. Over time, several other tumor entities have been identified to metabolize 5-ALA and show a similar fluorescence pattern during surgical resection. This case report is the first description of 5-ALA accumulation in postischemic cerebral tissue. This evidence questions the assumption that 5-ALA accumulation in glioma is exclusively attributed to tumor infiltration. Instead, 5-ALA accumulation can also occur beyond the tumor borders and may be partially ascribed to inflammatory changes in the surrounding brain tissue. A 64-year old woman presented with episodes of apraxia and a ring-enhancing lesion in postcontrast T1-weighted magnetic resonance sequences suggestive of high grade glioma. Strong fluorescence was observed during 5-ALA-guided resection. However, although the frozen section was inconclusive, the final histopathologic examination revealed a stage II cerebral infarction. 5-ALA accumulation in postischemic cerebral tissue should be considered for intended supramarginal resections near eloquent brain regions. Therefore, sufficient preoperative imaging should regularly include magnetic resonance imaging spectroscopy and perfusion sequences to ascertain the proper diagnosis. Moreover, further research is warranted to determine the role of 5-ALA accumulation in postischemic and inflammatory brain tissue. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Atmospheric rivers causing high accumulation storms in East Antarctica: regional climate model evaluation

    NASA Astrophysics Data System (ADS)

    Lazzara, M. A.; Tsukernik, M.; Gorodetskaya, I.

    2016-12-01

    Recent studies confirmed that atmospheric rivers (ARs) reach the continent of Antarctica and thus influence the Antarctic accumulation patterns and the ice sheet mass balance (Gorodetskaya et al. 2014, GRL). Similar to mid-latitude ARs, Antarctic ARs are associated with a blocking pattern downstream of a cyclone, which allows channeling of moisture toward the continent. However, due to the extremely cold atmosphere, Antarctic ARs possess some unique features. First, the existence of an AR in high latitudes is always associated with warm advection. Second, in order for an AR to penetrate the continent, it needs to overcome strong low-level outflow winds - katabatic winds - coming from the interior of the continent. Thirdly, sea ice surrounding the Antarctic ice sheet introduces an additional "cold barrier" decreasing the tropospheric moisture holding capacity and promoting precipitation before reaching the ice sheet. We believe these factors contribute to the scarcity of AR events influencing the ice sheet surface mass balance. Nevertheless, their presence is clearly seen in the long-term record. In particular, anomalous accumulation in 2009 and 2011 in Dronning Maud Land in East Antarctica has been linked to atmospheric rivers. We performed a detailed investigation of several AR storm events from 2009 and 2011 using the Weather Research and Forecasting (WRF) model simulations. These simulations depicted the synoptic scale development of storms that led to an anomalous precipitation pattern in the East Antarctic. We investigated the role of the upper level vs. lower level forcing in the formation of the contributing storms. The moisture and temperature anomalies of each case are evaluated in the context of synoptic and large-scale atmospheric forcing. We also performed sensitivity studies to determine the role of sea ice in the development of these systems.

  11. High-level expression of human immunodeficiency virus antigens from the tobacco and tomato plastid genomes.

    PubMed

    Zhou, Fei; Badillo-Corona, Jesus A; Karcher, Daniel; Gonzalez-Rabade, Nuria; Piepenburg, Katrin; Borchers, A-M Inka; Maloney, Alan P; Kavanagh, Tony A; Gray, John C; Bock, Ralph

    2008-12-01

    Transgene expression from the plant's plastid genome represents a promising strategy in molecular farming because of the plastid's potential to accumulate foreign proteins to high levels and the increased biosafety provided by the maternal mode of organelle inheritance. In this article, we explore the potential of transplastomic plants to produce human immunodeficiency virus (HIV) antigens as potential components of an acquired immunodeficiency syndrome (AIDS) vaccine. It is shown that the HIV antigens p24 (the major target of T-cell-mediated immune responses in HIV-positive individuals) and Nef can be expressed to high levels in plastids of tobacco, a non-food crop, and tomato, a food crop with an edible fruit. Optimized p24-Nef fusion gene cassettes trigger antigen protein accumulation to up to approximately 40% of the plant's total protein, demonstrating the great potential of transgenic plastids to produce AIDS vaccine components at low cost and high yield.

  12. Transformation of Solanum tuberosum plastids allows high expression levels of β-glucuronidase both in leaves and microtubers developed in vitro.

    PubMed

    Segretin, María Eugenia; Lentz, Ezequiel Matías; Wirth, Sonia Alejandra; Morgenfeld, Mauro Miguel; Bravo-Almonacid, Fernando Félix

    2012-04-01

    Plastid genome transformation offers an attractive methodology for transgene expression in plants, but for potato, only expression of gfp transgene (besides the selective gene aadA) has been published. We report here successful expression of β-glucuronidase in transplastomic Solanum tuberosum (var. Desiree) plants, with accumulation levels for the recombinant protein of up to 41% of total soluble protein in mature leaves. To our knowledge, this is the highest expression level reported for a heterologous protein in S. tuberosum. Accumulation of the recombinant protein in soil-grown minitubers was very low, as described in previous reports. Interestingly, microtubers developed in vitro showed higher accumulation of β-glucuronidase. As light exposure during their development could be the trigger for this high accumulation, we analyzed the effect of light on β-glucuronidase accumulation in transplastomic tubers. Exposure to light for 8 days increased β-glucuronidase accumulation in soil-grown tubers, acting as a light-inducible expression system for recombinant protein accumulation in tuber plastids. In this paper we show that plastid transformation in potato allows the highest recombinant protein accumulation in foliar tissue described so far for this food crop. We also demonstrate that in tubers high accumulation is possible and depends on light exposure. Because tubers have many advantages as protein storage organs, these results could lead to new recombinant protein production schemes based on potato.

  13. High extent of O-GlcNAcylation in breast cancer cells correlates with the levels of HAS enzymes, accumulation of hyaluronan, and poor outcome.

    PubMed

    Tiainen, Satu; Oikari, Sanna; Tammi, Markku; Rilla, Kirsi; Hämäläinen, Kirsi; Tammi, Raija; Kosma, Veli-Matti; Auvinen, Päivi

    2016-11-01

    Obesity and oversupply of glucose, e.g., due to nutritional factors may shape the tumor microenvironment favorable for tumor progression. O-GlcNAcylation, a reversible modification of intracellular proteins, influences on several cellular functions and is connected to many diseases including cancer. Glycosaminoglycan hyaluronan (HA) enhances tumor progression and in breast cancer HA accumulation associates strongly with poor outcome. In vitro studies have suggested that O-GlcNAcylation may enhance HA synthesis. The aim of this study was to investigate the correlations between O-GlcNAcylation, HA-related parameters, and disease outcome in a clinical breast cancer material consisting of 278 breast cancer cases. In microscopic analyses, O-GlcNAc staining of the breast carcinoma cells was evaluated in several randomly picked high-power fields of each section. The extent of cytoplasmic O-GlcNAc staining was graded as either low or high according to the intensity of the staining and the percentage of stained cells. The extent of nuclear O-GlcNAc staining was categorized as either low or high according to the percentage of stained nuclei. A high extent of both cytoplasmic and nuclear O-GlcNAcylation correlated with an increased relapse rate, development of distant metastases, and poor outcome. A high extent of cytoplasmic O-GlcNAcylation correlated also with the accumulation of all hyaluronan synthase (HAS1-3) proteins and with a large amount of HA in the tumor stroma. In addition, a high extent of nuclear O-GlcNAcylation associated with obesity. The results suggest a mechanistic association between increased O-GlcNAcylation and HA synthesis, leading to a HA-rich microenvironment favorable for breast cancer progression.

  14. Coastal barrier stratigraphy for Holocene high-resolution sea-level reconstruction

    PubMed Central

    Costas, Susana; Ferreira, Óscar; Plomaritis, Theocharis A.; Leorri, Eduardo

    2016-01-01

    The uncertainties surrounding present and future sea-level rise have revived the debate around sea-level changes through the deglaciation and mid- to late Holocene, from which arises a need for high-quality reconstructions of regional sea level. Here, we explore the stratigraphy of a sandy barrier to identify the best sea-level indicators and provide a new sea-level reconstruction for the central Portuguese coast over the past 6.5 ka. The selected indicators represent morphological features extracted from coastal barrier stratigraphy, beach berm and dune-beach contact. These features were mapped from high-resolution ground penetrating radar images of the subsurface and transformed into sea-level indicators through comparison with modern analogs and a chronology based on optically stimulated luminescence ages. Our reconstructions document a continuous but slow sea-level rise after 6.5 ka with an accumulated change in elevation of about 2 m. In the context of SW Europe, our results show good agreement with previous studies, including the Tagus isostatic model, with minor discrepancies that demand further improvement of regional models. This work reinforces the potential of barrier indicators to accurately reconstruct high-resolution mid- to late Holocene sea-level changes through simple approaches. PMID:27929122

  15. Coastal barrier stratigraphy for Holocene high-resolution sea-level reconstruction.

    PubMed

    Costas, Susana; Ferreira, Óscar; Plomaritis, Theocharis A; Leorri, Eduardo

    2016-12-08

    The uncertainties surrounding present and future sea-level rise have revived the debate around sea-level changes through the deglaciation and mid- to late Holocene, from which arises a need for high-quality reconstructions of regional sea level. Here, we explore the stratigraphy of a sandy barrier to identify the best sea-level indicators and provide a new sea-level reconstruction for the central Portuguese coast over the past 6.5 ka. The selected indicators represent morphological features extracted from coastal barrier stratigraphy, beach berm and dune-beach contact. These features were mapped from high-resolution ground penetrating radar images of the subsurface and transformed into sea-level indicators through comparison with modern analogs and a chronology based on optically stimulated luminescence ages. Our reconstructions document a continuous but slow sea-level rise after 6.5 ka with an accumulated change in elevation of about 2 m. In the context of SW Europe, our results show good agreement with previous studies, including the Tagus isostatic model, with minor discrepancies that demand further improvement of regional models. This work reinforces the potential of barrier indicators to accurately reconstruct high-resolution mid- to late Holocene sea-level changes through simple approaches.

  16. TRPV1 agonist monoacylglycerol increases UCP1 content in brown adipose tissue and suppresses accumulation of visceral fat in mice fed a high-fat and high-sucrose diet.

    PubMed

    Iwasaki, Yusaku; Tamura, Yasuko; Inayoshi, Kimiko; Narukawa, Masataka; Kobata, Kenji; Chiba, Hiroshige; Muraki, Etsuko; Tsunoda, Nobuyo; Watanabe, Tatsuo

    2011-01-01

    The administration of such a transient receptor potential vanilloid 1 (TRPV1) agonist as capsaicin, which is a pungent ingredient of red pepper, promotes energy metabolism and suppresses visceral fat accumulation. We have recently identified monoacylglycerols (MGs) having an unsaturated long-chain fatty acid as the novel TRPV1 agonist in foods. We investigated in this present study the effects of dietary MGs on uncoupling protein 1 (UCP1) expression in interscapular brown adipose tissue (IBAT) and on fat accumulation in mice fed with a high-fat, high-sucrose diet. The MG30 diet that substituted 30% of all lipids for MGs (a mixture of 1-oleoylglycerol, 1-linoleoylglycerol and 1-linolenoylglycerol) significantly increased the UCP1 content of IBAT and decreased the weight of epididymal white adipose tissue, and the serum glucose, total cholesterol and free fatty acid levels. The diet containing only 1-oleoylglycerol as MG also increased UCP1 expression in IBAT. MGs that activated TRPV1 also therefore induced the expression of UCP 1 and prevented visceral fat accumulation as well as capsaicin.

  17. Rapid Sediment Accumulation Results in High Methane Effluxes from Coastal Sediments

    PubMed Central

    Lenstra, Wytze; Jong, Dirk; Meysman, Filip J. R.; Sapart, Célia J.; van der Veen, Carina; Röckmann, Thomas; Gonzalez, Santiago; Slomp, Caroline P.

    2016-01-01

    Globally, the methane (CH4) efflux from the ocean to the atmosphere is small, despite high rates of CH4 production in continental shelf and slope environments. This low efflux results from the biological removal of CH4 through anaerobic oxidation with sulfate in marine sediments. In some settings, however, pore water CH4 is found throughout the sulfate-bearing zone, indicating an apparently inefficient oxidation barrier for CH4. Here we demonstrate that rapid sediment accumulation can explain this limited capacity for CH4 removal in coastal sediments. In a saline coastal reservoir (Lake Grevelingen, The Netherlands), we observed high diffusive CH4 effluxes from the sediment into the overlying water column (0.2–0.8 mol m-2 yr-1) during multiple years. Linear pore water CH4 profiles and the absence of an isotopic enrichment commonly associated with CH4 oxidation in a zone with high rates of sulfate reduction (50–170 nmol cm-3 d-1) both suggest that CH4 is bypassing the zone of sulfate reduction. We propose that the rapid sediment accumulation at this site (~ 13 cm yr-1) reduces the residence time of the CH4 oxidizing microorganisms in the sulfate/methane transition zone (< 5 years), thus making it difficult for these slow growing methanotrophic communities to build-up sufficient biomass to efficiently remove pore water CH4. In addition, our results indicate that the high input of organic matter (~ 91 mol C m-2 yr-1) allows for the co-occurrence of different dissimilatory respiration processes, such as (acetotrophic) methanogenesis and sulfate reduction in the surface sediments by providing abundant substrate. We conclude that anthropogenic eutrophication and rapid sediment accumulation likely increase the release of CH4 from coastal sediments. PMID:27560511

  18. Effects of dietary heme iron and exercise training on abdominal fat accumulation and lipid metabolism in high-fat diet-fed mice.

    PubMed

    Katsumura, Masanori; Takagi, Shoko; Oya, Hana; Tamura, Shohei; Saneyasu, Takaoki; Honda, Kazuhisa; Kamisoyama, Hiroshi

    2017-08-01

    Animal by-products can be recycled and used as sources of essential nutrients. Water-soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high-fat diet. Exercise-trained mice had significantly less perirenal adipose tissue, whereas WSHI-fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone-sensitive lipase. WSHI-fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation-related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism-related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high-fat diet. © 2016 Japanese Society of Animal Science.

  19. Chemicals to enhance microalgal growth and accumulation of high-value bioproducts

    PubMed Central

    Yu, Xinheng; Chen, Lei; Zhang, Weiwen

    2015-01-01

    Photosynthetic microalgae have attracted significant attention as they can serve as important sources for cosmetic, food and pharmaceutical products, industrial materials and even biofuel biodiesels. However, current productivity of microalga-based processes is still very low, which has restricted their scale-up application. In addition to various efforts in strain improvement and cultivation optimization, it was proposed that the productivity of microalga-based processes can also be increased using various chemicals to trigger or enhance cell growth and accumulation of bioproducts. Herein, we summarized recent progresses in applying chemical triggers or enhancers to improve cell growth and accumulation of bioproducts in algal cultures. Based on their enhancing mechanisms, these chemicals can be classified into four categories:chemicals regulating biosynthetic pathways, chemicals inducing oxidative stress responses, phytohormones and analogs regulating multiple aspects of microalgal metabolism, and chemicals directly as metabolic precursors. Taken together, the early researches demonstrated that the use of chemical stimulants could be a very effective and economical way to improve cell growth and accumulation of high-value bioproducts in large-scale cultivation of microalgae. PMID:25741321

  20. Effect of high fluoride and high fat on serum lipid levels and oxidative stress in rabbits.

    PubMed

    Sun, Liyan; Gao, Yanhui; Zhang, Wei; Liu, Hui; Sun, Dianjun

    2014-11-01

    The purpose of this study was to explore the effects of high fluoride and high fat on triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), total antioxidant capacity (T-AOC), lipid peroxide (LPO) and malondialdehyde (MDA) in rabbits. A factorial experimental design was used, with two factors (fluoride and fat) and three levels. Seventy-two male rabbits were randomly assigned into nine groups according to initial weight and serum lipid levels. The rabbits were fed with basic feed, moderate fat feed or high fat feed and drank tap water, fluoridated water at levels of 50 and 100mgfluorion/L freely. Biological materials were collected after 5 months, and serum lipid, T-AOC, LPO, and MDA levels were then measured. Using these data, the separate and interactive effects of high fluoride and high fat were analyzed. High fluoride and high fat both increased serum levels of TC, HDL-C and LDL-C significantly (P<0.05), and there was also a synergistic effect between high fluoride and high fat (P<0.05). High fluoride and high fat had different effects on TG levels: high fat significantly increased TG levels (P<0.01) whereas high fluoride had nothing to do with TG levels (P>0.05). High fat significantly elevated LPO and MDA levels and lowered T-AOC levels in serum (P<0.05). Similarly, high fluoride significantly increased LPO and MDA levels in serum (P<0.05). However, there was no interactive effect between high fat and high fluoride on these indexes. In summary, high fluoride and high fat increased serum TC and LDL-C levels individually and synergistically, and this would cause and aggravate hypercholesterolemia in rabbits. At the same time, high fluoride and high fat both made the accumulation of product of oxidative stress in experimental animals. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Lead and Arsenic Accumulation and Its Effects on Plasma Cortisol Levels in Oreochromis sp.

    PubMed

    Thang, Nguyen Quoc; Huy, Bui The; Van Tan, Le; Phuong, Nguyen Thi Kim

    2017-08-01

    The accumulation, elimination and effect of heavy metals on plasma cortisol levels in Oreochromis sp. were studied in the exposure and recovery phases. In the exposure phase, the mean rate of accumulation in the tissues was in the order gill > liver > muscle for Pb exposure and muscle > liver > gill for As exposure. In the recovery phase, the order of elimination in the tissues was gill > liver > muscle for Pb and liver > gill > muscle for As. The amount of cortisol secreted by the Oreochromis sp. after Pb or As treatment was lower compared to Oreochromis sp. in the control group during the exposure phase. In the recovery phase, plasma cortisol levels in Oreochromis sp. increased in all Pb treatment groups while it continuously decreased in all As treatment groups. A fish affected by As has obvious difficulty recovering from the stress response. It was concluded that exposure to the tested concentrations of Pb and As over 20 days could be a potent endocrine disruptor, which may lead to adverse impacts on the health of the Oreochromis sp.

  2. Regional Greenland accumulation variability from Operation IceBridge airborne accumulation radar

    NASA Astrophysics Data System (ADS)

    Lewis, Gabriel; Osterberg, Erich; Hawley, Robert; Whitmore, Brian; Marshall, Hans Peter; Box, Jason

    2017-03-01

    The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. An improved understanding of temporal and spatial variability of snow accumulation will reduce uncertainties in GrIS mass balance models and improve projections of Greenland's contribution to sea-level rise, currently estimated at 0.089 ± 0.03 m by 2100. Here we analyze 25 NASA Operation IceBridge accumulation radar flights totaling > 17 700 km from 2013 to 2014 to determine snow accumulation in the GrIS dry snow and percolation zones over the past 100-300 years. IceBridge accumulation rates are calculated and used to validate accumulation rates from three regional climate models. Averaged over all 25 flights, the RMS difference between the models and IceBridge accumulation is between 0.023 ± 0.019 and 0.043 ± 0.029 m w.e. a-1, although each model shows significantly larger differences from IceBridge accumulation on a regional basis. In the southeast region, for example, the Modèle Atmosphérique Régional (MARv3.5.2) overestimates by an average of 20.89 ± 6.75 % across the drainage basin. Our results indicate that these regional differences between model and IceBridge accumulation are large enough to significantly alter GrIS surface mass balance estimates. Empirical orthogonal function analysis suggests that the first two principal components account for 33 and 19 % of the variance, and correlate with the Atlantic Multidecadal Oscillation (AMO) and wintertime North Atlantic Oscillation (NAO), respectively. Regions that disagree strongest with climate models are those in which we have the fewest IceBridge data points, requiring additional in situ measurements to verify model uncertainties.

  3. Demise of reef-flat carbonate accumulation with late Holocene sea-level fall: Evidence from Molokai, Hawaii

    USGS Publications Warehouse

    Engels, M.S.; Fletcher, C.H.; Field, M.; Conger, C.L.; Bochicchio, C.

    2008-01-01

    Twelve cores from the protected reef-flat of Molokai revealed that carbonate sediment accumulation, ranging from 3 mm year-1 to less than 1 mm year-1, ended on average 2,500 years ago. Modern sediment is present as a mobile surface veneer but is not trapped within the reef framework. This finding is consistent with the arrest of deposition at the end of the mid-Holocene highstand, known locally as the "Kapapa Stand of the Sea," ???2 m above the present datum ca. 3,500 years ago in the main Hawaiian Islands. Subsequent erosion, non-deposition, and/or a lack of rigid binding were probable factors leading to the lack of reef-flat accumulation during the late Holocene sea-level fall. Given anticipated climate changes, increased sedimentation of reef-flat environments is to be expected as a consequence of higher sea level. ?? 2008 Springer-Verlag.

  4. A long-term high-fat diet changes iron distribution in the body, increasing iron accumulation specifically in the mouse spleen.

    PubMed

    Yamano, Noriko; Ikeda, Yasumasa; Sakama, Minoru; Izawa-Ishizawa, Yuki; Kihira, Yoshitaka; Ishizawa, Keisuke; Miyamoto, Licht; Tomita, Shuhei; Tsuchiya, Koichiro; Tamaki, Toshiaki

    2015-01-01

    Although iron is an essential trace metal, its presence in excess causes oxidative stress in the human body. Recent studies have indicated that iron storage is a risk factor for type 2 diabetes mellitus. Dietary iron restriction or iron chelation ameliorates symptoms of type 2 diabetes in mouse models. However, whether iron content in the body changes with the development of diabetes is unknown. Here, we investigated the dynamics of iron accumulation and changes in iron absorption-related genes in mice that developed obesity and diabetes by consuming a high-fat diet (HFD-fed mice). HFD-fed mice (18-20 wk) were compared with control mice for hematologic features, serum ferritin levels, and iron contents in the gastrocnemius muscle, heart, epididymal fat, testis, liver, duodenum, and spleen. In addition, the spleen was examined histologically. Iron absorption-related gene expression in the liver and duodenum was also examined. Hemoglobin and serum ferritin levels were increased in HFD-fed mice. The HFD-fed mice showed iron accumulation in the spleen, but not in the heart or liver. Increased percentages of the splenic red pulp and macrophages were observed in HFD-fed mice and iron accumulation in the spleen was found mainly in the splenic red pulp. The HFD-fed mice also showed decreased iron content in the duodenum. The mRNA expression of divalent metal transporter-1 (DMT-1), an iron absorption-related gene, was elevated in the duodenum of HFD-fed mice. These results indicate that iron accumulation (specifically accumulation in the spleen) is enhanced by the development of type 2 diabetes induced by HFD.

  5. Digital accumulators in phase and frequency tracking loops

    NASA Technical Reports Server (NTRS)

    Hinedi, Sami; Statman, Joseph I.

    1990-01-01

    Results on the effects of digital accumulators in phase and frequency tracking loops are presented. Digital accumulators or summers are used extensively in digital signal processing to perform averaging or to reduce processing rates to acceptable levels. For tracking the Doppler of high-dynamic targets at low carrier-to-noise ratios, it is shown through simulation and experiment that digital accumulators can contribute an additional loss in operating threshold. This loss was not considered in any previous study and needs to be accounted for in performance prediction analysis. Simulation and measurement results are used to characterize the loss due to the digital summers for three different tracking loops: a digital phase-locked loop, a cross-product automatic frequency tracking loop, and an extended Kalman filter. The tracking algorithms are compared with respect to their frequency error performance and their ability to maintain lock during severe maneuvers at various carrier-to-noise ratios. It is shown that failure to account for the effect of accumulators can result in an inaccurate performance prediction, the extent of which depends highly on the algorithm used.

  6. Design of chimeric expression elements that confer high-level gene activity in chromoplasts.

    PubMed

    Caroca, Rodrigo; Howell, Katharine A; Hasse, Claudia; Ruf, Stephanie; Bock, Ralph

    2013-02-01

    Non-green plastids, such as chromoplasts, generally have much lower activity of gene expression than chloroplasts in photosynthetically active tissues. Suppression of plastid genes in non-green tissues occurs through a complex interplay of transcriptional and translational control, with the contribution of regulation of transcript abundance versus translational activity being highly variable between genes. Here, we have investigated whether the low expression of the plastid genome in chromoplasts results from inherent limitations in gene expression capacity, or can be overcome by designing appropriate combinations of promoters and translation initiation signals in the 5' untranslated region (5'-UTR). We constructed chimeric expression elements that combine promoters and 5'-UTRs from plastid genes, which are suppressed during chloroplast-to-chromoplast conversion in Solanum lycopersicum (tomato) fruit ripening, either just at the translational level or just at the level of mRNA accumulation. These chimeric expression elements were introduced into the tomato plastid genome by stable chloroplast transformation. We report the identification of promoter-UTR combinations that confer high-level gene expression in chromoplasts of ripe tomato fruits, resulting in the accumulation of reporter protein GFP to up to 1% of total cellular protein. Our work demonstrates that non-green plastids are capable of expressing genes to high levels. Moreover, the chimeric cis-elements for chromoplasts developed here are widely applicable in basic and applied research using transplastomic methods. © 2012 The Authors The Plant Journal © 2012 Blackwell Publishing Ltd.

  7. Protein accumulation and rumen stability of wheat γ-gliadin fusion proteins in tobacco and alfalfa.

    PubMed

    Sun, Xiaodong; Chi-Ham, Cecilia L; Cohen-Davidyan, Tamar; DeBen, Christopher; Getachew, Girma; DePeters, Edward; Putnam, Daniel; Bennett, Alan

    2015-09-01

    The nutritional value of various crops can be improved by engineering plants to produce high levels of proteins. For example, because methionine deficiency limits the protein quality of Medicago Sativa (alfalfa) forage, producing alfalfa plants that accumulate high levels of a methionine-rich protein could increase the nutritional value of that crop. We used three strategies in designing methionine-rich recombinant proteins that could accumulate to high levels in plants and thereby serve as candidates for improving the protein quality of alfalfa forage. In tobacco, two fusion proteins, γ-gliadin-δ-zein and γ-δ-zein, as well as δ-zein co-expressed with β-zein, all formed protein bodies. However, the γ-gliadin-δ-zein fusion protein accumulated to the highest level, representing up to 1.5% of total soluble protein (TSP) in one transformant. In alfalfa, γ-gliadin-δ-zein accumulated to 0.2% of TSP, and in an in vitro rumen digestion assay, γ-gliadin-δ-zein was more resistant to microbial degradation than Rubisco. Additionally, although it did not form protein bodies, a γ-gliadin-GFP fusion protein accumulated to much higher levels, 7% of TSP, than a recombinant protein comprised of an ER localization signal fused to GFP in tobacco. Based on our results, we conclude that γ-gliadin-δ-zein is a potential candidate protein to use for enhancing methionine levels in plants and for improving rumen stability of forage protein. γ-gliadin fusion proteins may provide a general platform for increasing the accumulation of recombinant proteins in transgenic plants. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  8. Over-expression of LeNCED1 in tomato (Solanum lycopersicum L.) with the rbcS3C promoter allows recovery of lines that accumulate very high levels of abscisic acid and exhibit severe phenotypes.

    PubMed

    Tung, Swee Ang; Smeeton, Rachel; White, Charlotte A; Black, Colin R; Taylor, Ian B; Hilton, Howard W; Thompson, Andrew J

    2008-07-01

    Previous work where 9-cis-epoxycarotenoid dioxygenase (NCED) was over-expressed using the constitutive Gelvin Superpromoter resulted in mild increases in abscisic acid (ABA) accumulation, accompanied by stomatal closure and increased water-use efficiency (WUE), but with apparently little impact on long-term biomass production. However, one of the negative effects of the over-expression of NCED using constitutive promoters in tomato was increased seed dormancy. Here we report the use of the rbcS3C promoter, from a gene encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), to drive LeNCED1 transgene expression in tomato in a light-responsive and circadian manner. In comparison to the constitutive promoter, the rbcS3C promoter allowed the generation of transgenic plants with much higher levels of ABA accumulation in leaves and sap, but the effect on seed dormancy was diminished. These plants displayed the expected reductions in stomatal conductance and CO(2) assimilation, but they also exhibited a severe set of symptoms that included perturbed cotyledon release from the testa, increased photobleaching in young seedlings, substantially reduced chlorophyll and carotenoid content, interveinal leaf flooding, and greatly reduced growth. These symptoms illustrate adverse consequences of long-term, very high ABA accumulation. Only more moderate increases in ABA biosynthesis are likely to be useful in the context of agriculture. Implications are discussed for the design of transgenic 'high ABA' plants that exhibit increased WUE but have minimal negative phenotypic effects.

  9. Brevetoxins, like ciguatoxins, are potent ichthyotoxic neurotoxins that accumulate in fish✩

    PubMed Central

    Naar, Jerome P.; Flewelling, Leanne J.; Lenzi, Allison; Abbott, Jay P.; Granholm, April; Jacocks, Henry M.; Gannon, Damon; Henry, Michael; Pierce, Richard; Baden, Daniel G.; Wolny, Jennifer; Landsberg, Jan H.

    2009-01-01

    Brevetoxins and ciguatoxins are closely related potent marine neurotoxins. Although ciguatoxins accumulate in fish to levels that are dangerous for human consumption, live fish have not been considered as potential sources of brevetoxin exposure in humans. Here we show that, analogous to ciguatoxins, brevetoxins can accumulate in live fish by dietary transfer. We experimentally identify two pathways leading to brevetoxin-contaminated omnivorous and planktivorous fish. Fish fed with toxic shellfish and Karenia brevis cultures remained healthy and accumulated high brevetoxin levels in their tissues (up to 2675 ng g−1 in viscera and 1540 ng g−1 in muscle). Repeated collections of fish from St. Joseph Bay in the Florida panhandle reveal that accumulation of brevetoxins in healthy fish occurs in the wild. We observed that levels of brevetoxins in the muscle of fish at all trophic levels rise significantly, but not to dangerous levels, during a K. brevis bloom. Concentrations were highest in fish liver and stomach contents, and increased during and immediately following the bloom. The persistence of brevetoxins in the fish food web was followed for 1 year after the K. brevis bloom. PMID:17675204

  10. Trehalose accumulation enhances tolerance of Saccharomyces cerevisiae to acetic acid.

    PubMed

    Yoshiyama, Yoko; Tanaka, Koichi; Yoshiyama, Kohei; Hibi, Makoto; Ogawa, Jun; Shima, Jun

    2015-02-01

    Trehalose confers protection against various environmental stresses on yeast cells. In this study, trehalase gene deletion mutants that accumulate trehalose at high levels showed significant stress tolerance to acetic acid. The enhancement of trehalose accumulation can thus be considered a target in the breeding of acetic acid-tolerant yeast strains. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  11. Accumulation of Mn(II) in Deinococcus radiodurans Facilitates Gamma-Radiation Resistance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daly, Michael J.; Gaidamakova, E; Matrosova, V

    2004-11-05

    Deinococcus radiodurans is extremely resistant to ionizing radiation. How this bacterium can grow under chronic gamma-radiation (50 Gy/hour) or recover from acute doses greater than 10 kGy is unknown. We show that D. radiodurans accumulates very high intracellular manganese and low iron levels compared to radiation sensitive bacteria, and resistance exhibits a concentration-dependent response to Mn(II). Among the most radiation-resistant bacterial groups reported, Deinococcus, Enterococcus, Lactobacillus and cyanobacteria spp. accumulate Mn(II). In contrast, Shewanella oneidensis and Pseudomonas putida have high Fe but low intracellular Mn concentrations and are very sensitive. We propose that Mn(II) accumulation facilitates recovery from radiation injury.

  12. Accumulation of catechins in tea in relation to accumulation of mRNA from genes involved in catechin biosynthesis.

    PubMed

    Eungwanichayapant, P D; Popluechai, S

    2009-02-01

    Catechins are a group of polyphenols found in tea (Camellia sinensis var. sinensis) at high levels. They are beneficial for health. From the study on accumulation of catechins in shoots and mature leaves of a tea cultivar, Oolong No. 17, using high-performance liquid chromatography (HPLC), it was found that the amounts of most catechins in the shoots were higher than those in the mature leaves, with an exception of catechins gallate (CG) that was found in trace amounts in both the shoots and mature leaves. mRNA accumulation of genes involved in catechin synthesis was studied using reverse transcriptase-polymerase chain reaction (RT-PCR). The results showed that the mRNA accumulation of the genes were higher in the shoots than in the mature leaves. These genes included genes of phenylalanine ammonia-lyase 1 (PAL1; EC 4.3.1.5), chalcone synthase (CHS; EC 2.3.1.74), dihydroflavonol 4-reductase (DFR; EC 1.1.1.219), leucoanthocyanidin reductase (LCR; EC 1.17.1.3), and flavanone 3-hydroxylase (F3H; EC 1.14.11.9).

  13. Metallothionein expression in chloroplasts enhances mercury accumulation and phytoremediation capability

    PubMed Central

    Ruiz, Oscar N.; Alvarez, Derry; Torres, Cesar; Roman, Laura; Daniell, Henry

    2015-01-01

    Summary Genetic engineering to enhance mercury phytoremediation has been accomplished by expression of the merAB genes that protects the cell by converting Hg[II] into Hg[0] which volatilizes from the cell. A drawback of this approach is that toxic Hg is released back into the environment. A better phytoremediation strategy would be to accumulate mercury inside plants for subsequent retrieval. We report here the development of a transplastomic approach to express the mouse metallothionein gene (mt1) and accumulate mercury in high concentrations within plant cells. Real-time PCR analysis showed that up to 1284 copies of the mt1 gene were found per cell when compared with 1326 copies of the 16S rrn gene, thereby attaining homoplasmy. Past studies in chloroplast transformation used qualitative Southern blots to evaluate indirectly transgene copy number, whereas we used real-time PCR for the first time to establish homoplasmy and estimate transgene copy number and transcript levels. The mt1 transcript levels were very high with 183 000 copies per ng of RNA or 41% the abundance of the 16S rrn transcripts. The transplastomic lines were resistant up to 20 μm mercury and maintained high chlorophyll content and biomass. Although the transgenic plants accumulated high concentrations of mercury in all tissues, leaves accumulated up to 106 ng, indicating active phytoremediation and translocation of mercury. Such accumulation of mercury in plant tissues facilitates proper disposal or recycling. This study reports, for the first time, the use of metallothioniens in plants for mercury phytoremediation. Chloroplast genetic engineering approach is useful to express metal-scavenging proteins for phytoremediation. PMID:21518240

  14. Genetic Diversity, Rather than Cultivar Type, Determines Relative Grain Cd Accumulation in Hybrid Rice

    PubMed Central

    Sun, Liang; Xu, Xiaxu; Jiang, Youru; Zhu, Qihong; Yang, Fei; Zhou, Jieqiang; Yang, Yuanzhu; Huang, Zhiyuan; Li, Aihong; Chen, Lianghui; Tang, Wenbang; Zhang, Guoyu; Wang, Jiurong; Xiao, Guoying; Huang, Daoyou; Chen, Caiyan

    2016-01-01

    Cadmium (Cd) is a toxic element, and rice is known to be a leading source of dietary Cd for people who consume rice as their main caloric resource. Hybrid rice has dominated rice production in southern China and has been adopted worldwide. The characteristics of high yield heterosis of rice hybrids makes the public think intuitively that the hybrid rice accumulates more Cd in grain than do inbred cultivars. A detailed understanding of the genetic basis of grain Cd accumulation in hybrids and developing Cd-safe rice are one of the top priorities for hybrid rice breeders at present. In this study, we investigated genetic diversity and grain Cd levels in 617 elite rice hybrids collected from the middle and lower Yangtze River Valley in China and 68 inbred cultivars from around the world. We found that there are large variations in grain Cd accumulation in both the hybrids and their inbred counterparts. However, we found grain Cd levels in the rice hybrids to be similar to the levels in indica rice inbreds, suggesting that the hybrids do not accumulate more Cd than do the inbred rice cultivars. Further analysis revealed that the high heritability of Cd accumulation in the grain and the single indica population structure increases the risk of Cd over-accumulation in hybrid rice. The genetic effects of Cd-related QTLs, which have been identified in related Cd-QTL mapping studies, were also determined in the hybrid rice population. Four QTLs were identified as being associated with the variation in grain Cd levels; three of these loci exhibited obvious indica-japonica differentiations. Our study will provide a better understanding of grain Cd accumulations in hybrid rice, and pave the way toward effective breeding for high-yielding, low grain-Cd hybrids in the future. PMID:27708659

  15. Expression Patterns of Genes Involved in Sugar Metabolism and Accumulation during Apple Fruit Development

    PubMed Central

    Cheng, Lailiang

    2012-01-01

    Both sorbitol and sucrose are imported into apple fruit from leaves. The metabolism of sorbitol and sucrose fuels fruit growth and development, and accumulation of sugars in fruit is central to the edible quality of apple. However, our understanding of the mechanisms controlling sugar metabolism and accumulation in apple remains quite limited. We identified members of various gene families encoding key enzymes or transporters involved in sugar metabolism and accumulation in apple fruit using homology searches and comparison of their expression patterns in different tissues, and analyzed the relationship of their transcripts with enzyme activities and sugar accumulation during fruit development. At the early stage of fruit development, the transcript levels of sorbitol dehydrogenase, cell wall invertase, neutral invertase, sucrose synthase, fructokinase and hexokinase are high, and the resulting high enzyme activities are responsible for the rapid utilization of the imported sorbitol and sucrose for fruit growth, with low levels of sugar accumulation. As the fruit continues to grow due to cell expansion, the transcript levels and activities of these enzymes are down-regulated, with concomitant accumulation of fructose and elevated transcript levels of tonoplast monosaccharide transporters (TMTs), MdTMT1 and MdTMT2; the excess carbon is converted into starch. At the late stage of fruit development, sucrose accumulation is enhanced, consistent with the elevated expression of sucrose-phosphate synthase (SPS), MdSPS5 and MdSPS6, and an increase in its total activity. Our data indicate that sugar metabolism and accumulation in apple fruit is developmentally regulated. This represents a comprehensive analysis of the genes involved in sugar metabolism and accumulation in apple, which will serve as a platform for further studies on the functions of these genes and subsequent manipulation of sugar metabolism and fruit quality traits related to carbohydrates. PMID:22412983

  16. Elevated rates of organic carbon, nitrogen, and phosphorus accumulation in a highly impacted mangrove wetland

    NASA Astrophysics Data System (ADS)

    Sanders, Christian J.; Eyre, Bradley D.; Santos, Isaac R.; Machado, Wilson; Luiz-Silva, Wanilson; Smoak, Joseph M.; Breithaupt, Joshua L.; Ketterer, Michael E.; Sanders, Luciana; Marotta, Humberto; Silva-Filho, Emmanoel

    2014-04-01

    The effect of nutrient enrichment on mangrove sediment accretion and carbon accumulation rates is poorly understood. Here we quantify sediment accretion through radionuclide tracers to determine organic carbon (OC), total nitrogen (TN), and total phosphorus (TP) accumulation rates during the previous 60 years in both a nutrient-enriched and a pristine mangrove forest within the same geomorphological region of southeastern Brazil. The forest receiving high nutrient loads has accumulated OC, TN, and TP at rates that are fourfold, twofold, and eightfold respectively, higher than those from the undisturbed mangrove. Organic carbon and TN stable isotopes (δ13C and δ15N) reflect an increased presence of organic matter (OM) originating with either phytoplankton, benthic algae, or another allochthonous source within the more rapidly accumulated sediments of the impacted mangrove. This suggests that the accumulation rate of OM in eutrophic mangrove systems may be enhanced through the addition of autochthonous and allochthonous nonmangrove material.

  17. Enhanced acetyl-CoA production is associated with increased triglyceride accumulation in the green alga Chlorella desiccata

    PubMed Central

    Avidan, Omri; Brandis, Alexander; Rogachev, Ilana; Pick, Uri

    2015-01-01

    Triglycerides (TAGs) from microalgae can be utilized as food supplements and for biodiesel production, but little is known about the regulation of their biosynthesis. This work aimed to test the relationship between acetyl-CoA (Ac-CoA) levels and TAG biosynthesis in green algae under nitrogen deprivation. A novel, highly sensitive liquid chromatography mass spectrometry (LC-MS/MS) technique enabled us to determine the levels of Ac-CoA, malonyl-CoA, and unacetylated (free) CoA in green microalgae. A comparative study of three algal species that differ in TAG accumulation levels shows that during N starvation, Ac-CoA levels rapidly rise, preceding TAG accumulation in all tested species. The levels of Ac-CoA in the high TAG accumulator Chlorella desiccata exceed the levels in the moderate TAG accumulators Dunaliella tertiolecta and Chlamydomonas reinhardtii. Similarly, malonyl-CoA and free CoA levels also increase, but to lower extents. Calculated cellular concentrations of Ac-CoA are far lower than reported K mAc-CoA values of plastidic Ac-CoA carboxylase (ptACCase) in plants. Transcript level analysis of plastidic pyruvate dehydrogenase (ptPDH), the major chloroplastic Ac-CoA producer, revealed rapid induction in parallel with Ac-CoA accumulation in C. desiccata, but not in D. tertiolecta or C. reinhardtii. It is proposed that the capacity to accumulate high TAG levels in green algae critically depends on their ability to divert carbon flow towards Ac-CoA. This requires elevation of the chloroplastic CoA pool level and enhancement of Ac-CoA biosynthesis. These conclusions may have important implications for future genetic manipulation to enhance TAG biosynthesis in green algae. PMID:25922486

  18. Accumulate repeat accumulate codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, A.; Divsalar, D.; Yao, K.

    2004-01-01

    In this paper we propose an innovative channel coding scheme called Accumulate Repeat Accumulate codes. This class of codes can be viewed as trubo-like codes, namely a double serial concatenation of a rate-1 accumulator as an outer code, a regular or irregular repetition as a middle code, and a punctured accumulator as an inner code.

  19. Metallothionein expression in chloroplasts enhances mercury accumulation and phytoremediation capability.

    PubMed

    Ruiz, Oscar N; Alvarez, Derry; Torres, Cesar; Roman, Laura; Daniell, Henry

    2011-06-01

    Genetic engineering to enhance mercury phytoremediation has been accomplished by expression of the merAB genes that protects the cell by converting Hg[II] into Hg[0] which volatilizes from the cell. A drawback of this approach is that toxic Hg is released back into the environment. A better phytoremediation strategy would be to accumulate mercury inside plants for subsequent retrieval. We report here the development of a transplastomic approach to express the mouse metallothionein gene (mt1) and accumulate mercury in high concentrations within plant cells. Real-time PCR analysis showed that up to 1284 copies of the mt1 gene were found per cell when compared with 1326 copies of the 16S rrn gene, thereby attaining homoplasmy. Past studies in chloroplast transformation used qualitative Southern blots to evaluate indirectly transgene copy number, whereas we used real-time PCR for the first time to establish homoplasmy and estimate transgene copy number and transcript levels. The mt1 transcript levels were very high with 183,000 copies per ng of RNA or 41% the abundance of the 16S rrn transcripts. The transplastomic lines were resistant up to 20 μm mercury and maintained high chlorophyll content and biomass. Although the transgenic plants accumulated high concentrations of mercury in all tissues, leaves accumulated up to 106 ng, indicating active phytoremediation and translocation of mercury. Such accumulation of mercury in plant tissues facilitates proper disposal or recycling. This study reports, for the first time, the use of metallothioneins in plants for mercury phytoremediation. Chloroplast genetic engineering approach is useful to express metal-scavenging proteins for phytoremediation. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  20. Intercellular salicylic acid accumulation during compatible and incompatible Arabidopsis-Pseudomonas syringae interactions

    PubMed Central

    Wilson, Daniel C; Carella, Philip; Cameron, Robin K

    2014-01-01

    The phytohormone salicylic acid (SA) plays an important role in several disease resistance responses. During the Age-Related Resistance (ARR) response that occurs in mature Arabidopsis responding to Pseudomonas syringae pv tomato (Pst), SA accumulates in the intercellular space where it may act as an antimicrobial agent. Recently we measured intracellular and intercellular SA levels in young, ARR-incompetent plants responding to virulent and avirulent strains of Pst to determine if intercellular SA accumulation is a component of additional defense responses to Pst. In young plants virulent Pst suppressed both intra- and intercellular SA accumulation in a coronatine-dependent manner. In contrast, high levels of intra- and intercellular SA accumulated in response to avirulent Pst. Our results support the idea that SA accumulation in the intercellular space is an important component of multiple defense responses. Future research will include understanding how mature plants counteract the effects of coronatine during the ARR response. PMID:25763618

  1. Corticosterone administration and high-energy feed results in enhanced fat accumulation and insulin resistance in broiler chickens.

    PubMed

    Yuan, L; Lin, H; Jiang, K J; Jiao, H C; Song, Z G

    2008-07-01

    1. Two experiments were conducted to investigate the effects of exogenous corticosterone administration (30 mg/kg diet) and dietary energy level on feed or energy intake and fat deposition in broiler chickens of 1 and 4 weeks of age. 2. Corticosterone treatment significantly suppressed body weight (BW) gain and reduced feed and caloric efficiencies. The retarded growth may conceal the stimulatory effect of corticosterone on feed consumption or metabolisable energy (ME) intake. A high-energy diet may increase energy intake and partially alleviate the suppressing effect of corticosterone on growth of broilers. 3. Corticosterone administration promoted the conservation of energy stores as fat at both abdominal and subcutaneous sites and this process occurred regardless of dietary energy level in ad libitum feeding status. A high-energy diet increased fat accumulation and showed no significant interaction with corticosterone treatment. 4. The suppressed development of breast and thigh muscles by corticosterone treatment was observed only in 1-week-old chickens fed on the low-energy diet. In contrast, the yield of breast muscle but not thigh muscle was significantly decreased by corticosterone in 4-week-old chickens, suggesting that the tissue specificity to corticosterone challenge is age dependent. 5. Plasma concentrations of glucose, insulin, triglyceride, non-esterified fatty acids (NEFA) and very low density lipoprotein were increased by corticosterone treatment regardless of diet treatment. A high-energy diet increased plasma levels of NEFA and resulted in hyperinsulinism in 4-week-old chickens but not in 1-week-old chickens. 6. Lipoprotein lipase (LPL) activities in adipose tissues may have been up-regulated by corticosterone treatment and showed tissue specificity. The increased LPL activities at ad libitum feeding status were not necessarily linked with the increased fat accumulation in corticosterone challenged chickens. 7. Corticosterone resulted in augmented

  2. Implications of metal accumulation mechanisms to phytoremediation.

    PubMed

    Memon, Abdul R; Schröder, Peter

    2009-03-01

    Trace elements (heavy metals and metalloids) are important environmental pollutants, and many of them are toxic even at very low concentrations. Pollution of the biosphere with trace elements has accelerated dramatically since the Industrial Revolution. Primary sources are the burning of fossil fuels, mining and smelting of metalliferous ores, municipal wastes, agrochemicals, and sewage. In addition, natural mineral deposits containing particularly large quantities of heavy metals are found in many regions. These areas often support characteristic plant species thriving in metal-enriched environments. Whereas many species avoid the uptake of heavy metals from these soils, some of them can accumulate significantly high concentrations of toxic metals, to levels which by far exceed the soil levels. The natural phenomenon of heavy metal tolerance has enhanced the interest of plant ecologists, plant physiologists, and plant biologists to investigate the physiology and genetics of metal tolerance in specialized hyperaccumulator plants such as Arabidopsis halleri and Thlaspi caerulescens. In this review, we describe recent advances in understanding the genetic and molecular basis of metal tolerance in plants with special reference to transcriptomics of heavy metal accumulator plants and the identification of functional genes implied in tolerance and detoxification. Plants are susceptible to heavy metal toxicity and respond to avoid detrimental effects in a variety of different ways. The toxic dose depends on the type of ion, ion concentration, plant species, and stage of plant growth. Tolerance to metals is based on multiple mechanisms such as cell wall binding, active transport of ions into the vacuole, and formation of complexes with organic acids or peptides. One of the most important mechanisms for metal detoxification in plants appears to be chelation of metals by low-molecular-weight proteins such as metallothioneins and peptide ligands, the phytochelatins. For

  3. Contemporary deposition and long-term accumulation of sediment and nutrients by tidal freshwater forested wetlands impacted by sea level rise

    USGS Publications Warehouse

    Noe, Gregory; Hupp, Cliff R.; Bernhardt, Christopher E.; Krauss, Ken W.

    2016-01-01

    Contemporary deposition (artificial marker horizon, 3.5 years) and long-term accumulation rates (210Pb profiles, ~150 years) of sediment and associated carbon (C), nitrogen (N), and phosphorus (P) were measured in wetlands along the tidal Savannah and Waccamaw rivers in the southeastern USA. Four sites along each river spanned an upstream-to-downstream salinification gradient, from upriver tidal freshwater forested wetland (TFFW), through moderately and highly salt-impacted forested wetlands, to oligohaline marsh downriver. Contemporary deposition rates (sediment, C, N, and P) were greatest in oligohaline marsh and lowest in TFFW along both rivers. Greater rates of deposition in oligohaline and salt-stressed forested wetlands were associated with a shift to greater clay and metal content that is likely associated with a change from low availability of watershed-derived sediment to TFFW and to greater availability of a coastal sediment source to oligohaline wetlands. Long-term accumulation rates along the Waccamaw River had the opposite spatial pattern compared to contemporary deposition, with greater rates in TFFW that declined to oligohaline marsh. Long-term sediment and elemental mass accumulation rates also were 3–9× lower than contemporary deposition rates. In comparison to other studies, sediment and associated nutrient accumulation in TFFW are lower than downriver/estuarine freshwater, oligohaline, and salt marshes, suggesting a reduced capacity for surface sedimentation (short-term) as well as shallow soil processes (long-term sedimentation) to offset sea level rise in TFFW. Nonetheless, their potentially large spatial extent suggests that TFFW have a large impact on the transport and fate of sediment and nutrients in tidal rivers and estuaries.

  4. Characteristic of nitrous oxide production in partial denitrification process with high nitrite accumulation.

    PubMed

    Du, Rui; Peng, Yongzhen; Cao, Shenbin; Wang, Shuying; Niu, Meng

    2016-03-01

    Nitrous oxide (N2O) production during the partial denitrification process with nitrate (NO3(-)-N) to nitrite (NO2(-)-N) transformation ratio of 80% was investigated in this study. Results showed that N2O was seldom observed before complete depletion of NO3(-)-N, but it was closely related to the reduction of NO2(-)-N rather than NO3(-)-N. High COD/NO3(-)-N was in favor of N2O production in partial denitrification with high NO2(-)-N accumulation. It was seriously enhanced at constant acidic pH due to the free nitrous acid (FNA) inhibition. However, the N2O production was much lower at initial pH of 5.5 and 6.5 due to the pH increase during denitrification process. Significantly, the pH turning point could be chosen as a controlled parameter to denote the end of NO3(-)-N reduction, which could not only achieve high NO2(-)-N accumulation but also decrease the N2O production significantly for practical application. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Heat input and accumulation for ultrashort pulse processing with high average power

    NASA Astrophysics Data System (ADS)

    Finger, Johannes; Bornschlegel, Benedikt; Reininghaus, Martin; Dohrn, Andreas; Nießen, Markus; Gillner, Arnold; Poprawe, Reinhart

    2018-05-01

    Materials processing using ultrashort pulsed laser radiation with pulse durations <10 ps is known to enable very precise processing with negligible thermal load. However, even for the application of picosecond and femtosecond laser radiation, not the full amount of the absorbed energy is converted into ablation products and a distinct fraction of the absorbed energy remains as residual heat in the processed workpiece. For low average power and power densities, this heat is usually not relevant for the processing results and dissipates into the workpiece. In contrast, when higher average powers and repetition rates are applied to increase the throughput and upscale ultrashort pulse processing, this heat input becomes relevant and significantly affects the achieved processing results. In this paper, we outline the relevance of heat input for ultrashort pulse processing, starting with the heat input of a single ultrashort laser pulse. Heat accumulation during ultrashort pulse processing with high repetition rate is discussed as well as heat accumulation for materials processing using pulse bursts. In addition, the relevance of heat accumulation with multiple scanning passes and processing with multiple laser spots is shown.

  6. Reflectance of litter accumulation levels at five wavelengths within the 0.5- to 2.5 micron waveband

    NASA Technical Reports Server (NTRS)

    Gerbermann, A. H.; Everitt, J. H.; Gausman, H. W. (Principal Investigator)

    1982-01-01

    Reflectance was measured for 1-m2 range grass plots with two canopy treatments (standing and clipped) and four levels of litter accumulation and for grain sorghum with two canopy treatments. Reflectance was significantly higher at the 0.65- to 1.65-, and 2.20-micrometer. Wavelengths for both grass and grain sorghum canopies when the canopies were clipped and the resulting litter was removed. The natural accumulation of litter under the grass canopy did not significantly affect reflectance. The 1.65- and 2.20-micrometer wavelength reflectances of the live grass and the intact litter were 21.8% and 16.2%, respectively, and those of grain sorghum were 21.8% and 16.5%, respectively.

  7. Genetic manipulation of the γ-aminobutyric acid (GABA) shunt in rice: overexpression of truncated glutamate decarboxylase (GAD2) and knockdown of γ-aminobutyric acid transaminase (GABA-T) lead to sustained and high levels of GABA accumulation in rice kernels.

    PubMed

    Shimajiri, Yasuka; Oonishi, Takayuki; Ozaki, Kae; Kainou, Kumiko; Akama, Kazuhito

    2013-06-01

    Gamma-aminobutyric acid (GABA) is a non-protein amino acid commonly present in all organisms. Because cellular levels of GABA in plants are mainly regulated by synthesis (glutamate decarboxylase, GAD) and catabolism (GABA-transaminase, GABA-T), we attempted seed-specific manipulation of the GABA shunt to achieve stable GABA accumulation in rice. A truncated GAD2 sequence, one of five GAD genes, controlled by the glutelin (GluB-1) or rice embryo globulin promoters (REG) and GABA-T-based trigger sequences in RNA interference (RNAi) cassettes controlled by one of these promoters as well, was introduced into rice (cv. Koshihikari) to establish stable transgenic lines under herbicide selection using pyriminobac. T₁ and T₂ generations of rice lines displayed high GABA concentrations (2-100 mg/100 g grain). In analyses of two selected lines from the T₃ generation, there was a strong correlation between GABA level and the expression of truncated GAD2, whereas the inhibitory effect of GABA-T expression was relatively weak. In these two lines both with two T-DNA copies, their starch, amylose, and protein levels were slightly lower than non-transformed cv. Koshihikari. Free amino acid analysis of mature kernels of these lines demonstrated elevated levels of GABA (75-350 mg/100 g polished rice) and also high levels of several amino acids, such as Ala, Ser, and Val. Because these lines of seeds could sustain their GABA content after harvest (up to 6 months), the strategy in this study could lead to the accumulation GABA and for these to be sustained in the edible parts. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  8. Hemothorax with a high carbohydrate antigen 19-9 level caused by a bronchogenic cyst.

    PubMed

    Tsuzuku, Akifumi; Asano, Fumihiro; Murakami, Anri; Masuda, Atsunori; Sobajima, Takuya; Matsuno, Yoshihiko; Matsumoto, Shinsuke; Mori, Yoshio; Takiya, Hiroshi; Iwata, Hitoshi

    2014-01-01

    A 58-year-old man presented with right-sided chest pain. Radiography and computed tomography showed a pleural effusion in the right chest and a mass in the right hilum. Thoracentesis showed a hemothorax. The carbohydrate antigen (CA) 19-9 level in the pleural effusion was very high, requiring differentiation from malignancy. Positron emission tomography showed no significant fluorodeoxy glucose (FDG) accumulation. Magnetic resonance imaging revealed a cystic lesion. The tumor was resected for both a diagnosis and treatment. A pathological examination demonstrated a bronchogenic cyst. An immunohistochemical study suggested that the cyst was the source of the hemothorax and the high CA19-9 level.

  9. Triacylglycerol Metabolism, Function, and Accumulation in Plant Vegetative Tissues.

    PubMed

    Xu, Changcheng; Shanklin, John

    2016-04-29

    Oils in the form of triacylglycerols are the most abundant energy-dense storage compounds in eukaryotes, and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerols as a renewable and sustainable bioenergy source. Here, we review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals.

  10. Betaine alleviates hepatic lipid accumulation via enhancing hepatic lipid export and fatty acid oxidation in rats fed with a high-fat diet.

    PubMed

    Xu, Li; Huang, Danping; Hu, Qiaolin; Wu, Jing; Wang, Yizhen; Feng, Jie

    2015-06-28

    To assess the effects of betaine on hepatic lipid accumulation and investigate the underlying mechanism, thirty-two male Sprague-Dawley rats weighing 100 (sd 2·50) g were divided into four groups, and started on one of four treatments: basal diet, basal diet with betaine administration, high-fat diet and high-fat diet with betaine administration. The results showed that no significant difference of body weight was found among experimental groups. Compared with high-fat diet-fed rats, a betaine supplementation decreased (P< 0·05) hepatic TAG accumulation induced by high-fat diet, which was also supported by hepatic histology results. Additionally, hepatic betaine-homocysteine methyltransferase concentration [corrected] as well as its mRNA abundance and lecithin level were found increased (P< 0·05) by betaine supplementation in both basal diet-fed rats and high-fat diet-fed rats. Betaine administration in high-fat diet-fed rats exhibited a higher (P< 0·05) concentration [corrected] of hepatic carnitine palmitoyltransferase 1 (CPT1) compared with high-fat diet-fed rats. High-fat diet inhibited (P< 0·05) the gene expression of hepatic PPARα and CPT1. However, betaine administration in high-fat diet-fed rats elevated (P< 0·05) the gene expression of PPARα and CPT1. Moreover, concentration, gene and protein expressions of hepatic fibroblast growth factor 21 (FGF21) were increased (P< 0·05) in response to betaine administration in high-fat diet group; meanwhile the gene expression of hepatic AMP-activated protein kinase was increased (P< 0·05) as well. The results suggest that betaine administration enhanced hepatic lipid export and fatty acid oxidation in high-fat diet-fed rats, thus effectively alleviating fat accumulation in the liver.

  11. High-density carrier-accumulated and electrically stable oxide thin-film transistors from ion-gel gate dielectric

    PubMed Central

    Fujii, Mami N.; Ishikawa, Yasuaki; Miwa, Kazumoto; Okada, Hiromi; Uraoka, Yukiharu; Ono, Shimpei

    2015-01-01

    The use of indium–gallium–zinc oxide (IGZO) has paved the way for high-resolution uniform displays or integrated circuits with transparent and flexible devices. However, achieving highly reliable devices that use IGZO for low-temperature processes remains a technological challenge. We propose the use of IGZO thin-film transistors (TFTs) with an ionic-liquid gate dielectric in order to achieve high-density carrier-accumulated IGZO TFTs with high reliability, and we discuss a distinctive mechanism for the degradation of this organic–inorganic hybrid device under long-term electrical stress. Our results demonstrated that an ionic liquid or gel gate dielectric provides highly reliable and low-voltage operation with IGZO TFTs. Furthermore, high-density carrier accumulation helps improve the TFT characteristics and reliability, and it is highly relevant to the electronic phase control of oxide materials and the degradation mechanism for organic–inorganic hybrid devices. PMID:26677773

  12. High-density carrier-accumulated and electrically stable oxide thin-film transistors from ion-gel gate dielectric.

    PubMed

    Fujii, Mami N; Ishikawa, Yasuaki; Miwa, Kazumoto; Okada, Hiromi; Uraoka, Yukiharu; Ono, Shimpei

    2015-12-18

    The use of indium-gallium-zinc oxide (IGZO) has paved the way for high-resolution uniform displays or integrated circuits with transparent and flexible devices. However, achieving highly reliable devices that use IGZO for low-temperature processes remains a technological challenge. We propose the use of IGZO thin-film transistors (TFTs) with an ionic-liquid gate dielectric in order to achieve high-density carrier-accumulated IGZO TFTs with high reliability, and we discuss a distinctive mechanism for the degradation of this organic-inorganic hybrid device under long-term electrical stress. Our results demonstrated that an ionic liquid or gel gate dielectric provides highly reliable and low-voltage operation with IGZO TFTs. Furthermore, high-density carrier accumulation helps improve the TFT characteristics and reliability, and it is highly relevant to the electronic phase control of oxide materials and the degradation mechanism for organic-inorganic hybrid devices.

  13. High infestation levels of Schizotetranychus oryzae severely affects rice metabolism.

    PubMed

    Blasi, Édina A R; Buffon, Giseli; Rativa, Angie G S; Lopes, Mara C B; Berger, Markus; Santi, Lucélia; Lavallée-Adam, Mathieu; Yates, John R; Schwambach, Joséli; Beys-da-Silva, Walter O; Sperotto, Raul A

    2017-12-01

    High levels of Schizotetranychus oryzae phytophagous mite infestation on rice leaves can severely affect productivity. Physiological characterization showed that S. oryzae promotes a decrease in chlorophyll concentration and the establishment of a senescence process in rice leaves. Late-infested leaves also present high levels of superoxide radical and hydrogen peroxide accumulation, along with high levels of membrane integrity loss, which is indicative of cell death. To better understand the rice molecular responses to high levels of mite infestation, we employed the Multidimensional Protein Identification Technology (MudPIT) approach to identify differentially expressed proteins. We identified 83 and 88 proteins uniquely present in control and late-infested leaves, respectively, along with 11 and one proteins more abundant in control and late-infested leaves, respectively. S. oryzae infestation induces a decreased abundance of proteins related to translation, protease inhibition, and photosynthesis. On the other hand, infestation caused increased abundance of proteins involved in protein modification and degradation. Our results also suggest that S. oryzae infestation interferes with intracellular transport, DNA structure maintenance, and amino acid and lipid metabolism in rice leaves. Proteomic data were positively correlated with enzymatic assays and RT-qPCR analysis. Our findings describe the protein expression patterns of late-infested rice leaves and suggest several targets which could be tested in future biotechnological approaches aiming to avoid the population increase of phytophagous mite in rice plants. Copyright © 2017 Elsevier GmbH. All rights reserved.

  14. Accumulation, metabolism and toxicity of parathion in tadpoles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hall, R.J.

    1990-04-01

    Earlier work exposing tadpoles to organophosphorus pesticides indicated the great resistance of tadpoles of the bullfrog (Rana catesbeiana) to these chemicals and their surprising ability to accumulate parathion and fenthion from water. These qualities seemed to make them an ideal model with which to test a hypothesis advanced by Burke and Ferguson, who noted that parathion is more toxic to resistant mosquitofish in static water than in flowing water--a reversal of the pattern normally seen. They believed that highly toxic metabolite paraoxon was produced by the fish and that its buildup in static systems resulted in the unexpected mortality. Amphibiansmore » have been shown to produce paraoxon and to accumulate the parent compound parathion to levels that are potentially hazardous to other organisms. In the course of examining paraoxon production by tadpoles, it would also be possible to learn more about their patterns of parathion uptake and elimination. Retention of residues is also a matter of concern given the high levels observed in the earlier studies.« less

  15. Carbon accumulation in high-altitude peatlands of the Central Andes of Peru

    NASA Astrophysics Data System (ADS)

    Llanos, Romina; Moreira-Turcq, Patricia; Huaman, Yizet; Espinoza, Raul; Apaestegui, James; Turcq, Bruno; Willems, Bram

    2017-04-01

    Despite covering only 6 - 8% of the world's land surface, peatlands contain around one third of the global organic soil carbon (C) and are an important component of the global C cycle. Most studies of peatland C dynamics have been carried out on boreal and subarctic peatlands, but less is known about peatlands at lower latitudes, yet there are significant peatland C stocks in these regions that may be more vulnerable to future climate change because they are closer to the climatic limit of peatland distribution. In South America, peatlands in high altitudes called "bofedales" represent one of the most important water resources and also provide key environmental services that support both Andean mountain biodiversity and the wellbeing of human populations. Nowdays, the need for conservation and wise use of these ecosystems is increasingly being recognized. So, a useable assessment of peatlands in the global C cycle requires accurate estimates of carbon pools and fluxes. In order to understand the impact of different altitudes on the growth, production and carbon accumulation, several short (about 30 cm) peatlands cores were collected in the headwater of the Cachi river basin, in the Central Andes of Peru. Two Distichia muscoides cushion plant-dominated "bofedales" which elevations exceed 4000 m were studied. The sedimentation rates, based on radiocarbon dating of peat samples from the two sites studied, were very variable. Cores from the bofedal located at 4200 m present an age of approximately 55 years, while the site at the highest altitude site has an age of approximately about 450 years. Our results point out very different rates of sedimentation in the two peatlands that may be related to the climatic changes observed during the recent past, with a direct consequence on the carbon accumulation rates. In the determination of the annual growth, we observed that this one presented smaller values in the first centimeters of the peatland with lower elevation, while

  16. Cynanchum wilfordii Radix attenuates liver fat accumulation and damage by suppressing hepatic cyclooxygenase-2 and mitogen-activated protein kinase in mice fed with a high-fat and high-fructose diet.

    PubMed

    Jang, Seon-A; Lee, SungRyul; Sohn, Eun-Hwa; Yang, Jaehyuk; Park, Dae Won; Jeong, Yong Joon; Kim, Inhye; Kwon, Jung Eun; Song, Hae Seong; Cho, Young Mi; Meng, Xue; Koo, Hyun Jung; Kang, Se Chan

    2016-09-01

    Excessive consumption of fat and fructose augments the pathological progression of nonalcoholic fatty liver disease through hepatic fibrosis, inflammation, and hepatic de novo lipogenesis. We hypothesized that supplementation with Cynanchum wilfordii extract (CWE) decreases fat accumulation in the liver by suppressing cyclooxygenase-2 (COX-2), the nuclear translocation of nuclear factor κB (NF-κB), and p38 mitogen-activated protein kinase (MAPK). The beneficial effect of CWE was evaluated in a murine model of nonalcoholic fatty liver disease. Mice were fed either a normal diet or an atherogenic diet with fructose (ATHFR) in the presence or absence of CWE (50, 100, or 200 mg/kg; n=6/group). Treatment with ATHFR induced a hepatosplenomegaly-like condition (increased liver and spleen weight); this pathological change was attenuated in the presence of CWE. The ATHFR group exhibited impaired liver function, as evidenced by increased blood levels of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase, fat accumulation in the liver, and lipid profiles. Supplementation of CWE (100 and 200 mg/kg, P<.05) ameliorated these impaired liver functions. Atherogenic diet with fructose increased the protein levels of COX-2 and p38 MAPK, as well as the nuclear translocation of NF-κB. These signaling pathways, which are associated with the inflammatory response, were markedly suppressed after CWE treatment (100 and 200 mg/kg). In summary, CWE supplementation reduced high-fat and high-fructose diet-induced fat accumulation and damage in the liver by suppressing COX-2, NF-κB, and p38 MAPK. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Altered Expression of OsNLA1 Modulates Pi Accumulation in Rice (Oryza sativa L.) Plants

    PubMed Central

    Zhong, Sihui; Mahmood, Kashif; Bi, Yong-Mei; Rothstein, Steven J.; Ranathunge, Kosala

    2017-01-01

    Current agricultural practices rely on heavy use of fertilizers for increased crop productivity. However, the problems associated with heavy fertilizer use, such as high cost and environmental pollution, require the development of crop species with increased nutrient use efficiency. In this study, by using transgenic approaches, we have revealed the critical role of OsNLA1 in phosphate (Pi) accumulation of rice plants. When grown under sufficient Pi and nitrate levels, OsNLA1 knockdown (Osnla1-1, Osnla1-2, and Osnla1-3) lines accumulated higher Pi content in their shoot tissues compared to wild-type, whereas, over-expression lines (OsNLA1-OE1, OsNLA1-OE2, and OsNLA1-OE3) accumulated the least levels of Pi. However, under high Pi levels, knockdown lines accumulated much higher Pi content compared to wild-type and exhibited Pi toxicity symptoms in the leaves. In contrast, the over-expression lines had 50–60% of the Pi content of wild-type and did not show such symptoms. When grown under limiting nitrate levels, OsNLA1 transgenic lines also displayed a similar pattern in Pi accumulation and Pi toxicity symptoms compared to wild-type suggesting an existence of cross-talk between nitrogen (N) and phosphorous (P), which is regulated by OsNLA1. The greater Pi accumulation in knockdown lines was a result of enhanced Pi uptake/permeability of roots compared to the wild-type. The cross-talk between N and P was found to be nitrate specific since the knockdown lines failed to over-accumulate Pi under low (sub-optimal) ammonium level. Moreover, OsNLA1 was also found to interact with OsPHO2, a known regulator of Pi homeostasis, in a Yeast Two-Hybrid (Y2H) assay. Taken together, these results show that OsNLA1 is involved in Pi homeostasis regulating Pi uptake and accumulation in rice plants and may provide an opportunity to enhance P use efficiency by manipulating nitrate supply in the soil. PMID:28626465

  18. Cell wall metabolism and hexose allocation contribute to biomass accumulation in high yielding extreme segregants of a Saccharum interspecific F2 population.

    PubMed

    Wai, Ching Man; Zhang, Jisen; Jones, Tyler C; Nagai, Chifumi; Ming, Ray

    2017-10-11

    Sugarcane is an emerging dual-purpose biofuel crop for energy and sugar production, owing to its rapid growth rate, high sucrose storage in the stems, and high lignocellulosic yield. It has the highest biomass production reaching 1.9 billion tonnes in 2014 worldwide. To improve sugarcane biomass accumulation, we developed an interspecific cross between Saccharum officinarum 'LA Purple' and Saccharum robustum 'MOL5829'. Selected F1 individuals were self-pollinated to generate a transgressive F2 population with a wide range of biomass yield. Leaf and stem internodes of fourteen high biomass and eight low biomass F2 extreme segregants were used for RNA-seq to decipher the molecular mechanism of rapid plant growth and dry weight accumulation. Gene Ontology terms involved in cell wall metabolism and carbohydrate catabolism were enriched among 3274 differentially expressed genes between high and low biomass groups. Up-regulation of cellulose metabolism, pectin degradation and lignin biosynthesis genes were observed in the high biomass group, in conjunction with higher transcript levels of callose metabolic genes and the cell wall loosening enzyme expansin. Furthermore, UDP-glucose biosynthesis and sucrose conversion genes were differentially expressed between the two groups. A positive correlation between stem glucose, but not sucrose, levels and dry weight was detected. We thus postulated that the high biomass sugarcane plants rapidly convert sucrose to UDP-glucose, which is the building block of cell wall polymers and callose, in order to maintain the rapid plant growth. The gene interaction of cell wall metabolism, hexose allocation and cell division contributes to biomass yield.

  19. Tissue accumulation and urinary excretion of chromium in rats fed diets containing graded levels of chromium chloride or chromium picolinate.

    PubMed

    Yoshida, Munehiro; Hatakeyama, Erika; Hosomi, Ryota; Kanda, Seiji; Nishiyama, Toshimasa; Fukunaga, Kenji

    2010-08-01

    To attempt a risk assessment of the excess intake of trivalent chromium (Cr), tissue Cr accumulation and urinary Cr excretion were examined in weanling rats fed experimental diets containing graded levels of Cr chloride (CrCl3) or Cr picolinate (CrPic). Thirty-six male weanling 4-weeks-old Wistar rats were divided into six groups and fed a casein-based semi-purified diet (Cr content: <0.02 microg/g) supplemented with 1, 10, or 100 microg Cr/g as CrCl3 or CrPic for 28 days. Among the experimental groups, no significant difference was observed in body weight; however, supplementation of 100 microg Cr/g to the diets caused a significant low liver weight irrespective of the chemical species of Cr. Activities of serum aspartate aminotransferase and alanine aminotransferase were significantly elevated in rats given CrPic at 100 microg Cr/g. In the liver, kidney and femur, Cr accumulation increased with elevation of the dietary Cr level. No influence of the difference in the chemical species of supplemented Cr was observed in the liver and kidney, but CrCl3 caused significantly higher Cr accumulation than CrPic in the femur of rats given 100 microg Cr/g. Daily urinary Cr excretion elevated with the increase of the dietary Cr level. Rats given CrPic showed significantly higher daily urinary Cr excretion than those given CrCl3, particularly at a dietary Cr level of 100 microg/g. The rate of urinary Cr excretion in rats given CrPic was constant, irrespective of the dietary Cr level, but that of rats given CrCl3 fell with the increase of the dietary Cr level. These results indicate that the lowest adverse effect level of dietary Cr is less than 100 microg/g, irrespective of the chemical species of Cr.

  20. Chloride and sulfate salinity effects on selenium accumulation by tall fescue. [Festuca arundinacea Schreb

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin Wu; Zhang-Zhi Huang

    The discovery of high levels of Se in soil and water samples from the San Joaquin Valley, California, and of its responsibility for deformity and death of wildlife at Kesterson National Wildlife Refuge have renewed interest in the bioaccumulation of this element. Greenhouse nutrient solution culture and field experiments were conducted to examine the effects of Cl and SO{sub 4} salt on growth and Se accumulation in tall fescue (Festuca arundinacea Schreb.) cultivars Alta, Falcon, and Olympic. Sulfate salt substantially reduced growth inhibition and Se accumulation. Tall fescue from the field irrigated with water low in salinity had higher tissuemore » Se concentration than plants from the field irrigated with water high in salinity. No difference in tissue Se concentration was found among the three tall fescue cultivars; however, forage-type Alta produced the most shoot biomass and accumulated the most total Se. The soil irrigated with water high in salinity had 10 times higher Se concentration than soil irrigated with water low in salinity. The highest soil Se concentration was found in the top 15 cm of soil. Growing fescue for one year reduced soil Se by 50%. Selenium concentrations below 15-cm depth were lower and similar between the bare soil and the soil under tall fescue. Both the high and low salinity water irrigations did not cause high levels of Se accumulation by the tall fescue cultivars unless there was continual addition of Se into the system. This study generated important information for Se bioaccumulation management in soils with elevated salinity and Se levels.« less

  1. Transcript profiling and gene characterization of three fatty acid desaturase genes in high, moderate, and low linolenic acid genotypes of flax (Linum usitatissimum L.) and their role in linolenic acid accumulation.

    PubMed

    Banik, Mitali; Duguid, Scott; Cloutier, Sylvie

    2011-06-01

    Three genes encoding fatty acid desaturase 3 (fad3a, fad3b, and a novel fad3c) were cloned from four flax genotypes varying in linolenic acid content. Real-time PCR was used to quantify expression levels of the three fad3 genes during seed development. High amounts of both fad3a and fad3b transcripts were observed and reached their peak levels at 20 days after anthesis, except for fad3a from SP2047 where only low level expression was observed throughout seed development. Transcript accumulation of the novel fad3c gene was at similar background levels. The fatty acid composition was analysed for all genotypes and stages of development and compared with the fad3 gene expression patterns. α-Linolenic acid gradually accumulated during seed development, while linoleic acid was transient and decreased in M5791, UGG5-5, and AC McDuff. In contrast, the linolenic acid present in the early stages of development nearly completely disappeared in SP2047, while linoleic acid steadily accumulated. fad3a of the low linolenic acid line SP2047 encoded a truncated protein caused by a premature stop codon resulting from a single point mutation, and the low level of transcript accumulation in this genotype is likely due to nonsense-mediated mRNA decay caused by the premature termination of translation as a result of this early stop codon. Although substantial amounts of transcript accumulation occurred with fad3b of SP2047 genotype, cloning of the gene revealed a mutation in the first histidine box causing an amino acid change. Heterologous expression in yeast of the SP2047 and UGG5-5 fad3b genes showed that the mutation in the histidine box in SP2047 caused the enzyme inactivity. Taken together, these results showed that fad3a and fad3b are responsible for linolenic acid accumulation in flax seeds but did not support a major role for the novel fad3c. These observations were further supported by phenotypic and genotypic assessment of a doubled haploid population. Expression patterns

  2. Mercury contamination in human hair and fish from Cambodia: levels, specific accumulation and risk assessment.

    PubMed

    Agusa, Tetsuro; Kunito, Takashi; Iwata, Hisato; Monirith, In; Tana, Touch Seang; Subramanian, Annamalai; Tanabe, Shinsuke

    2005-03-01

    Mercury (Hg) concentrations in human hair and fish samples from Phnom Penh, Kien Svay, Tomnup Rolork and Batrong, Cambodia, collected in November 1999 and December 2000 were determined to understand the status of contamination, and age- and sex-dependent accumulation in humans and to assess the intake of mercury via fish consumption. Mercury concentrations in human hair ranged from 0.54 to 190mug/g dry wt. About 3% of the samples contained Hg levels exceeding the no observed adverse effects level (NOAEL) of WHO (50mug/g) and the levels in some hair samples of women also exceeded the NOAEL (10mug/g) associated with fetus neurotoxicity. A weak but significant positive correlation was observed between age and Hg levels in hair of residents. Mercury concentrations in muscle of marine and freshwater fish from Cambodia ranged from <0.01 to 0.96mug/g wet wt. Mercury intake rates were estimated on the basis of the Hg content in fish and daily fish consumption. Three samples of marine fish including sharp-tooth snapper and obtuse barracuda, and one sample of sharp-tooth snapper exceeded the guidelines by US EPA and by Joint FAO/WHO Expert Committee on Food Additives (JECFA), respectively, which indicates that some fish specimens examined (9% and 3% for US EPA and JECFA guidelines, respectively) were hazardous for consumption at the ingestion rate of Cambodian people (32.6g/day). It is suggested that fish is probably the main source of Hg for Cambodian people. However, extremely high Hg concentrations were observed in some individuals and could not be explained by Hg intake from fish consumption, indicating some other contamination sources of Hg in Cambodia.

  3. The Effects of Dietary Carotenoid Supplementation and Retinal Carotenoid Accumulation on Vision-Mediated Foraging in the House Finch

    PubMed Central

    Toomey, Matthew B.; McGraw, Kevin J.

    2011-01-01

    Background For many bird species, vision is the primary sensory modality used to locate and assess food items. The health and spectral sensitivities of the avian visual system are influenced by diet-derived carotenoid pigments that accumulate in the retina. Among wild House Finches (Carpodacus mexicanus), we have found that retinal carotenoid accumulation varies significantly among individuals and is related to dietary carotenoid intake. If diet-induced changes in retinal carotenoid accumulation alter spectral sensitivity, then they have the potential to affect visually mediated foraging performance. Methodology/Principal Findings In two experiments, we measured foraging performance of house finches with dietarily manipulated retinal carotenoid levels. We tested each bird's ability to extract visually contrasting food items from a matrix of inedible distracters under high-contrast (full) and dimmer low-contrast (red-filtered) lighting conditions. In experiment one, zeaxanthin-supplemented birds had significantly increased retinal carotenoid levels, but declined in foraging performance in the high-contrast condition relative to astaxanthin-supplemented birds that showed no change in retinal carotenoid accumulation. In experiments one and two combined, we found that retinal carotenoid concentrations predicted relative foraging performance in the low- vs. high-contrast light conditions in a curvilinear pattern. Performance was positively correlated with retinal carotenoid accumulation among birds with low to medium levels of accumulation (∼0.5–1.5 µg/retina), but declined among birds with very high levels (>2.0 µg/retina). Conclusion/Significance Our results suggest that carotenoid-mediated spectral filtering enhances color discrimination, but that this improvement is traded off against a reduction in sensitivity that can compromise visual discrimination. Thus, retinal carotenoid levels may be optimized to meet the visual demands of specific behavioral tasks and

  4. Low Level Chlorpyrifos Exposure Increases Anandamide Accumulation in Juvenile Rat Brain in the Absence of Brain Cholinesterase Inhibition

    PubMed Central

    Carr, Russell L.; Graves, Casey A.; Mangum, Lee C.; Nail, Carole A.; Ross, Matthew K.

    2014-01-01

    The prevailing dogma is that chlorpyrifos (CPF) mediates its toxicity through inhibition of cholinesterase (ChE). However, in recent years, the toxicological effects of developmental CPF exposure have been attributed to an unknown non-cholinergic mechanism of action. We hypothesize that the endocannabinoid system may be an important target because of its vital role in nervous system development. We have previously reported that repeated exposure to CPF results in greater inhibition of fatty acid amide hydrolase (FAAH), the enzyme that metabolizes the endocannabinoid anandamide (AEA), than inhibition of either forebrain ChE or monoacylglycerol lipase (MAGL), the enzyme that metabolizes the endocannabinoid 2-arachidonylglycerol (2-AG). This exposure resulted in the accumulation of 2-AG and AEA in the forebrain of juvenile rats; however, even at the lowest dosage level used (1.0 mg/kg), forebrain ChE inhibition was still present. Thus, it is not clear if FAAH activity would be inhibited at dosage levels that do not inhibit ChE. To determine this, 10 day old rat pups were exposed daily for 7 days to either corn oil or 0.5 mg/kg CPF by oral gavage. At 4 and 12 h post-exposure on the last day of administration, the activities of serum ChE and carboxylesterase (CES) and forebrain ChE, MAGL, and FAAH were determined as well as the forebrain AEA and 2-AG levels. Significant inhibition of serum ChE and CES was present at both 4 and 12 h. There was no significant inhibition of the activities of forebrain ChE or MAGL and no significant change in the amount of 2-AG at either time point. On the other hand, while no statistically significant effects were observed at 4 h, FAAH activity was significantly inhibited at 12 h resulting in a significant accumulation of AEA. Although it is not clear if this level of accumulation impacts brain maturation, this study demonstrates that developmental CPF exposure at a level that does not inhibit brain ChE can alter components of

  5. Late 20th Century increase in South Pole snow accumulation

    USGS Publications Warehouse

    Mosley-Thompson, E.; Paskievitch, J.F.; Gow, A.J.; Thompson, L.G.

    1999-01-01

    A compilation of the 37-year history of net accumulation at the South Pole [Mosley-Thompson et al., 1995] suggests an increase in net annual accumulation since 1965. This record is sporadic and its quality is compromised by spatially restricted observations and nonsystematic measurement procedures. Results from a new, spatially extensive network of 236 accumulation poles document that the current 5-year (1992-1997) average annual net accumulation at the South Pole is 84.5??8.9 mm water equivalent (w.e.). This accumulation rate reflects a 30% increase since the 1960s when the best, although not optimal, records indicate that it was 65 mm w.e. Identification of two prominent beta radioactivity horizons (1954/1955 and 1964/1965) in six firn cores confirms an increase in accumulation since 1965. Viewed from a longer perspective of accumulation provided by ice cores and a snow mine study, the net accumulation of the 30-year period, 1965-1994, is the highest 30-year average of this millennium. Limited data suggest this recent accumulation increase extends beyond the South Pole region and may be characteristic of the high East Antarctic Plateau. Enhanced accumulation over the polar ice sheets has been identified as a potential early indicator of warmer sea surface temperatures and may offset a portion of the current rise in global sea level. Copyright 1999 by the American Geophysical Union.

  6. Heavy metals accumulation affects bone microarchitecture in osteoporotic patients.

    PubMed

    Scimeca, Manuel; Feola, Maurizio; Romano, Lorenzo; Rao, Cecilia; Gasbarra, Elena; Bonanno, Elena; Brandi, Maria Luisa; Tarantino, Umberto

    2017-04-01

    Bone metabolism is affected by mechanical, genetic, and environmental factors and plays a major role in osteoporosis. Nevertheless, the influence of environmental pollution on the occurrence of osteoporosis is still unclear and controversial. In this context, heavy metals are the most important pollutants capable to affect bone mass. The aim of this study was to investigate whether heavy metals accumulation in bone tissues could be related to the altered bone metabolism and architecture of osteoporotic patients. To this end, we analyzed 25 bone head biopsies osteoporotic patients and 25 bone head biopsies of osteoarthritic patients. Moreover we enrolled 15 patients underwent hip arthroplasty for high-energy hip fracture or osteonecrosis of the femoral head as a control group. Bone head biopsies were studied by BioQuant-osteo software, scanning electron microscopy and Energy Dispersive X-ray microanalysis. We found a prevalence of lead, cadmium and chromium accumulation in osteoporotic patients. Noteworthy, high levels of sclerostin, detected by immunohistochemistry, correlate with the accumulation of heavy metal found in the bone of osteoporotic patients, suggesting a molecular link between heavy metal accumulation and bone metabolism impairment. In conclusion, the presence of heavy metals into bone shed new light on the comprehension of the pathogenesis of osteoporosis since these elements could play a non redundant role in the development of osteoporosis at cellular/molecular and epigenetic level. Nevertheless, in vivo and in vitro studies need to better elucidate the molecular mechanism in which heavy metals can participate to osteoporosis. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1333-1342, 2017. © 2016 Wiley Periodicals, Inc.

  7. Triacylglycerol Metabolism, Function, and Accumulation in Plant Vegetative Tissues

    DOE PAGES

    Xu, Changcheng; Shanklin, John

    2016-02-03

    One of the most abundant energy-dense storage compounds in eukaryotes are oils in the form of triacylglycerols , and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Moreover, plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerolsmore » as a renewable and sustainable bioenergy source. We review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals.« less

  8. Low Medium pH Value Enhances Anthocyanin Accumulation in Malus Crabapple Leaves

    PubMed Central

    Tian, Ji; Jin, Kaina; Yao, Yuncong

    2014-01-01

    Anthocyanin is a critical factor involved in coloration of plant tissues, but the mechanism how medium pH values affect anthocyanin accumulation in woody plants is unknown. We analyzed anthocyanin composition and the expression of elements encoding anthocyanin and flavonols biosynthesis underlying different medium pH values by using three different leave color type cultivars. HPLC analysis demonstrated that high medium pH values treatment induced a dramatic decrease in the concentration of cyaniding in crabapple leaves. Conversely, the high medium pH values induced up-regulation of the content of flavones and flavonols, suggesting that low pH treatment-induced anthocyanin accumulation. Quantitative real time PCR experiment showed the expression level of anthocyanidin synthase (McANS) and uridine diphosphate glucose flavonoid 3-O-glucosyltransferase (McUFGT) was up-regulated by low pH values treatment, and high medium pH value treatment up-regulate the transcription level of flavonol synthase (McFLS). Meanwhile, several MYB TFs have been suggested in the regulation of pH responses. These results strongly indicate that the low pH treatment-induced anthocyanin accumulation is mediated by the variation of mRNA transcription of the anthocyanin biosynthetic genes. PMID:24914811

  9. Influence of muscle fiber type composition on early fat accumulation under high-fat diet challenge.

    PubMed

    Hua, Ning; Takahashi, Hirokazu; Yee, Grace M; Kitajima, Yoichiro; Katagiri, Sayaka; Kojima, Motoyasu; Anzai, Keizo; Eguchi, Yuichiro; Hamilton, James A

    2017-01-01

    To investigate whether differences in muscle fiber types affect early-stage fat accumulation, under high fat diet challenge in mice. Twelve healthy male C57BL/6 mice experienced with short-term (6 weeks) diet treatment for the evaluation of early pattern changes in muscular fat. The mice were randomly divided into two groups: high fat diet (n = 8) and normal control diet (n = 4). Extra- and intra-myocellular lipid (EMCL and IMCL) in lumbar muscles (type I fiber predominant) and tibialis anterior (TA) muscle (type II fiber predominant) were determined using magnetic resonance spectroscopy (MRS). Correlation of EMCL, IMCL and their ratio between TA and lumbar muscles was evaluated. EMCL increased greatly in both muscle types after high fat diet. IMCL in TA and lumbar muscles increased to a much lower extent, with a slightly greater increase in TA muscles. EMCLs in the 2 muscles were positively correlated (r = 0.84, p = 0.01), but IMCLs showed a negative relationship (r = -0.84, p = 0.01). In lumbar muscles, high fat diet significantly decreased type I fiber while it increased type II fiber (all p≤0.001). In TA muscle, there was no significant fiber type shifting (p>0.05). Under short-time high fat diet challenge, lipid tends to initially accumulate extra-cellularly. In addition, compared to type II dominant muscle, Type I dominant muscle was less susceptible to IMCL accumulation but more to fiber type shifting. These phenomena might reflect compensative responses of skeletal muscle to dietary lipid overload in order to regulate metabolic homeostasis.

  10. Multiple anatomy optimization of accumulated dose

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watkins, W. Tyler, E-mail: watkinswt@virginia.edu; Siebers, Jeffrey V.; Moore, Joseph A.

    Purpose: To investigate the potential advantages of multiple anatomy optimization (MAO) for lung cancer radiation therapy compared to the internal target volume (ITV) approach. Methods: MAO aims to optimize a single fluence to be delivered under free-breathing conditions such that the accumulated dose meets the plan objectives, where accumulated dose is defined as the sum of deformably mapped doses computed on each phase of a single four dimensional computed tomography (4DCT) dataset. Phantom and patient simulation studies were carried out to investigate potential advantages of MAO compared to ITV planning. Through simulated delivery of the ITV- and MAO-plans, target dosemore » variations were also investigated. Results: By optimizing the accumulated dose, MAO shows the potential to ensure dose to the moving target meets plan objectives while simultaneously reducing dose to organs at risk (OARs) compared with ITV planning. While consistently superior to the ITV approach, MAO resulted in equivalent OAR dosimetry at planning objective dose levels to within 2% volume in 14/30 plans and to within 3% volume in 19/30 plans for each lung V20, esophagus V25, and heart V30. Despite large variations in per-fraction respiratory phase weights in simulated deliveries at high dose rates (e.g., treating 4/10 phases during single fraction beams) the cumulative clinical target volume (CTV) dose after 30 fractions and per-fraction dose were constant independent of planning technique. In one case considered, however, per-phase CTV dose varied from 74% to 117% of prescription implying the level of ITV-dose heterogeneity may not be appropriate with conventional, free-breathing delivery. Conclusions: MAO incorporates 4DCT information in an optimized dose distribution and can achieve a superior plan in terms of accumulated dose to the moving target and OAR sparing compared to ITV-plans. An appropriate level of dose heterogeneity in MAO plans must be further investigated.« less

  11. Accumulation of senescent cells in mitotic tissue of aging primates.

    PubMed

    Jeyapalan, Jessie C; Ferreira, Mark; Sedivy, John M; Herbig, Utz

    2007-01-01

    Cellular senescence, a stress induced growth arrest of somatic cells, was first documented in cell cultures over 40 years ago, however its physiological significance has only recently been demonstrated. Using novel biomarkers of cellular senescence we examined whether senescent cells accumulate in tissues from baboons of ages encompassing the entire lifespan of this species. We show that dermal fibroblasts, displaying markers of senescence such as telomere damage, active checkpoint kinase ATM, high levels of heterochromatin proteins and elevated levels of p16, accumulate in skin biopsies from baboons with advancing age. The number of dermal fibroblasts containing damaged telomeres reaches a value of over 15% of total fibroblasts, whereas 80% of cells contain high levels of the heterochromatin protein HIRA. In skeletal muscle, a postmitotic tissue, only a small percentage of myonuclei containing damaged telomeres were detected regardless of animal age. The presence of senescent cells in mitotic tissues might therefore be a contributing factor to aging and age related pathology and provides further evidence that cellular senescence is a physiological event.

  12. Accumulation of Senescent Cells in Mitotic Tissue of Aging Primates

    PubMed Central

    Jeyapalan, Jessie C.; Ferreira, Mark; Sedivy, John M.; Herbig, Utz

    2013-01-01

    Cellular senescence, a stress induced growth arrest of somatic cells, was first documented in cell cultures over forty years ago, however its physiological significance has only recently been demonstrated. Using novel biomarkers of cellular senescence we examined whether senescent cells accumulate in tissues from baboons of ages encompassing the entire lifespan of this species. We show that dermal fibroblasts, displaying markers of senescence such as telomere damage, active checkpoint kinase ATM, high levels of heterochromatin proteins and elevated levels of p16, accumulate in skin biopsies from baboons with advancing age. The number of dermal fibroblasts containing damaged telomeres reaches a value of over 15% of total fibroblasts, whereas 80% of cells contain high levels of the heterochromatin protein HIRA. In skeletal muscle, a postmitotic tissue, only a small percentage of myonuclei containing damaged telomeres were detected regardless of animal age. The presence of senescent cells in mitotic tissues might therefore be a contributing factor to aging and age related pathology and provides further evidence that cellular senescence is a physiological event. PMID:17116315

  13. Clusterin deficiency induces lipid accumulation and tissue damage in kidney.

    PubMed

    Heo, Jung-Yoon; Kim, Ji-Eun; Dan, Yongwook; Kim, Yong-Woon; Kim, Jong-Yeon; Cho, Kyu Hyang; Bae, Young Kyung; Im, Seung-Soon; Liu, Kwang-Hyeon; Song, In-Hwan; Kim, Jae-Ryong; Lee, In-Kyu; Park, So-Young

    2018-05-01

    Clusterin is a secretory glycoprotein that is involved in multiple physiopathological processes, including lipid metabolism. Previous studies have shown that clusterin prevents hepatic lipid accumulation via suppression of sterol regulatory element-binding protein (SREBP) 1. In this study, we examined the role of clusterin in renal lipid accumulation in clusterin-knockout mice and NRK52e tubular epithelial cells. Clusterin deficiency increased the expression of SREBP1 and its target genes and decreased malonyl-CoA decarboxylase protein levels in the kidney. Expression of the endocytic receptor, megalin, and scavenger receptor class A was increased in clusterin-deficient mice. Functional analysis of lipid metabolism also revealed that lipid uptake and triglyceride synthesis were increased and fatty acid oxidation was reduced, leading to increased lipid accumulation in clusterin-deficient mice. These phenomena were accompanied by mesangial expansion, fibrosis and increased urinary protein-to-creatinine ratio. High-fat feeding aggravated these clusterin deficiency-induced pathological changes. Clusterin knockdown in NRK52e cells increased lipogenic gene expression and lipid levels, whereas overexpression of clusterin by treatment with adenovirus or recombinant clusterin protein suppressed lipogenic gene expression and lipid levels. Transforming growth factor-beta 1 (TGFB1) expression increased in the kidney of clusterin-deficient mice and suppression of TGFB1 in NRK52e cells suppressed lipid accumulation. These results suggest that clusterin deficiency induces renal lipid accumulation by dysregulating the expression of lipid metabolism-related factors and TGFB1, thereby leading to chronic kidney disease. Hence, clusterin may serve as a therapeutic target for lipid-induced chronic kidney disease. © 2018 Society for Endocrinology.

  14. Estimation of erosion-accumulative processes at the Inia River's mouth near high-rise construction zones.

    NASA Astrophysics Data System (ADS)

    Sineeva, Natalya

    2018-03-01

    Our study relevance is due to the increasing man-made impact on water bodies and associated land resources within the urban areas, as a consequence, by a change in the morphology and dynamics of Rivers' canals. This leads to the need to predict the development of erosion-accumulation processes, especially within the built-up urban areas. Purpose of the study is to develop programs on the assessment of erosion-accumulation processes at a water body, a mouth area of the Inia River, in the of perspective high-rise construction zone of a residential microdistrict, the place, where floodplain-channel complex is intensively expected to develop. Results of the study: Within the velocities of the water flow comparing, full-scale measured conditions, and calculated from the model, a slight discrepancy was recorded. This allows us to say that the numerical model reliably describes the physical processes developing in the River. The carried out calculations to assess the direction and intensity of the channel re-formations, made us possible to conclude, there was an insignificant predominance of erosion processes over the accumulative ones on the undeveloped part of the Inia River (the processes activity is noticeable only in certain areas (by the coasts and the island)). Importance of the study: The study on the erosion-accumulation processes evaluation can be used in design decisions for the future high-rise construction of this territory, which will increase their economic efficiency.

  15. Seasonal arsenic accumulation in stream sediments at a groundwater discharge zone.

    PubMed

    MacKay, Allison A; Gan, Ping; Yu, Ran; Smets, Barth F

    2014-01-21

    Seasonal changes in arsenic and iron accumulation rates were examined in the sediments of a brook that receives groundwater discharges of arsenic and reduced iron. Clean glass bead columns were deployed in sediments for known periods over the annual hydrologic cycle to monitor changes in arsenic and iron concentrations in bead coatings. The highest accumulation rates occurred during the dry summer period (July-October) when groundwater discharges were likely greatest at the sample locations. The intermediate flow period (October-March), with higher surface water levels, was associated with losses of arsenic and iron from bead column coatings at depths below 2-6 cm. Batch incubations indicated iron releases from solids to be induced by biological reduction of iron (oxy)hydroxide solids. Congruent arsenic releases during incubation were limited by the high arsenic sorption capacity (0.536 mg(As)/mg(Fe)) of unreacted iron oxide solids. The flooded spring (March-June) with high surface water flows showed the lowest arsenic and iron accumulation rates in the sediments. Comparisons of accumulation rates across a shoreline transect were consistent with greater rates at regions exposed above surface water levels for longer times and greater losses at locations submerged below surface water. Iron (oxy)hydroxide solids in the shallowest sediments likely serve as a passive barrier to sorb arsenic released to pore water at depth by biological iron reduction.

  16. Phytic Acid Synthesis and Vacuolar Accumulation in Suspension-Cultured Cells of Catharanthus roseus Induced by High Concentration of Inorganic Phosphate and Cations1[w

    PubMed Central

    Mitsuhashi, Naoto; Ohnishi, Miwa; Sekiguchi, Yoko; Kwon, Yong-Uk; Chang, Young-Tae; Chung, Sung-Kee; Inoue, Yoshinori; Reid, Robert J.; Yagisawa, Hitoshi; Mimura, Tetsuro

    2005-01-01

    We have established a new system for studying phytic acid, myo-inositol hexakisphosphate (InsP6) synthesis in suspension-cultured cells of Catharanthus. InsP6 and other intermediates of myo-inositol (Ins) phosphate metabolism were measured using an ion chromatography method. The detection limit for InsP6 was less than 50 nm, which was sufficient to analyze Ins phosphates in living cells. Synthesis of Ins phosphates was induced by incubation in high inorganic phosphate medium. InsP6 was mainly accumulated in vacuoles and was enhanced when cells were grown in high concentration of inorganic phosphates with the cations K+, Ca2+, or Zn2+. However, there was a strong tendency for InsP6 to accumulate in the vacuole in the presence of Ca2+ and in nonvacuolar compartments when supplied with Zn2+, possibly due to precipitation of InsP6 with Zn2+ in the cytosol. A vesicle transport inhibitor, brefeldin A, stimulated InsP6 accumulation. The amounts of both Ins(3)P1 myo-inositol monophosphate synthase, a key enzyme for InsP6 synthesis, and Ins(1,4,5)P3 kinase were unrelated to the level of accumulation of InsP6. The mechanisms for InsP6 synthesis and localization into vacuoles in plant cells are discussed. PMID:15965017

  17. Anthocyanin-rich Phytochemicals from Aronia Fruits Inhibit Visceral Fat Accumulation and Hyperglycemia in High-fat Diet-induced Dietary Obese Rats.

    PubMed

    Takahashi, Azusa; Shimizu, Hisae; Okazaki, Yukako; Sakaguchi, Hirohide; Taira, Toshio; Suzuki, Takashi; Chiji, Hideyuki

    2015-01-01

    Aronia fruits (chokeberry: Aronia melanocarpa E.) containing phenolic phytochemicals, such as cyanidin 3-glycosides and chlorogenic acid, have attracted considerable attention because of their potential human health benefits in humans including antioxidant activities and ability to improved vision. In the present study, the effects of anthocyanin-rich phytochemicals from aronia fruits (aronia phytochemicals) on visceral fat accumulation and fasting hyperglycemia were examined in rats fed a high-fat diet (Experiment 1). Total visceral fat mass was significantly lower in rats fed aronia phytochemicals than that in both the control group and bilberry phytochemicals-supplemented rats (p < 0.05). Moreover, perirenal and epididymal adipose tissue mass in rats fed aronia phytochemicals was significantly lower than that in both the control and bilberry phytochemicals group. Additionally, the mesenteric adipose tissue mass in aronia phytochemicals-fed rats was significantly low (p < 0.05). Furthermore, the fasting blood glucose levels significantly decreased in rats fed aronia phytochemicals for 4 weeks compared to that in the control rats (p < 0.05). Therefore, we investigated the effects of phytochemicals on postprandial hyperlipidemia after corn oil loading in rats, pancreatic lipase activity in vitro, and the plasma glycemic response after sucrose loading in order to elucidate the preventive factor of aronia phytochemical on visceral fat accumulation. In the oral corn oil tolerance tests (Experiment 2), aronia phytochemicals significantly inhibited the increases in plasma triglyceride levels, with a half-maximal inhibitory concentration (IC(50)) of 1.50 mg/mL. However, the inhibitory activity was similar to that of bilberry and tea catechins. In the sucrose tolerance tests (Experiment 3), aronia phytochemicals also significantly inhibited the increases in blood glucose levels that were observed in the control animals (p < 0.05). These results suggest that anthocyanin

  18. Pancreatic Fat Accumulation, Fibrosis, and Acinar Cell Injury in the Zucker Diabetic Fatty Rat Fed a Chronic High-Fat Diet

    PubMed Central

    Matsuda, Akiko; Makino, Naohiko; Tozawa, Tomohiro; Shirahata, Nakao; Honda, Teiichiro; Ikeda, Yushi; Sato, Hideyuki; Ito, Miho; Kakizaki, Yasuharu; Akamatsu, Manabu; Ueno, Yoshiyuki; Kawata, Sumio

    2014-01-01

    Objective The histological alteration of the exocrine pancreas in obesity has not been clarified. In the present study, we investigated biochemical and histological changes in the exocrine pancreas of obese model rats. Methods Zucker lean rats were fed a standard diet, and Zucker diabetic fatty (ZDF) rats were divided into 2 groups fed a standard diet and a high-fat diet, respectively. These experimental groups were fed each of the diets from 6 weeks until 12, 18, 24 weeks of age. We performed blood biochemical assays and histological analysis of the pancreas. Results In the ZDF rats fed a high-fat diet, the ratio of accumulated pancreatic fat area relative to exocrine gland area was increased significantly at 18 weeks of age in comparison with the other 2 groups (P < 0.05), and lipid droplets were observed in acinar cells. Subsequently, at 24 weeks of age in this group, pancreatic fibrosis and the serum exocrine pancreatic enzyme levels were increased significantly relative to the other 2 groups (P < 0.01). Conclusions In ZDF rats fed a chronic high-fat diet, fat accumulates in pancreatic acinar cells, and this fatty change seems to be related to subsequent pancreatic fibrosis and acinar cell injury. PMID:24717823

  19. Law of damage accumulation and fracture criteria in highly filled polymer materials

    NASA Astrophysics Data System (ADS)

    Bykov, D. L.; Kazakov, A. V.; Konovalov, D. N.; Mel'nikov, V. P.; Milyokhin, Yu. M.; Peleshko, V. A.; Sadovnichii, D. N.

    2014-09-01

    We present the results of a large series of experiments aimed at the study of laws of damage accumulation and fracture in highly filled polymer materials under loading conditions of various types: monotone, repeated, low- and high-cycle, with varying type of stress state, dynamic (in general, more than 50 programs implemented on specimens from one lot of material). The data obtained in these test allow one to make conclusions about the constitutive role of the attained maximum of strain intensity when estimating the accumulated damage in the process of uniaxial tension by various programs (in particular, an additional cyclic deformation below the preliminary attained strain maximum does not affect the limit values of strain and stress in the subsequent active extension), about the strong influence of the stress state on the deformation and fracture, about the specific features of the nonlinear behavior of the material under the shock loading conditions and its influence on the repeated deformation. All tests are described (with an accuracy acceptable in practical calculations, both with respect to stresses and strains in the process of loading and at the moment of fracture) in the framework of the same model of nonlinear viscoelasticity with the same set of constants. The constants of the proposed model are calculated according to a relatively simple algorithm by using the results of standard uniaxial tension tests with constant values of the strain rate and hydrostatic pressure (each test for 2-3 levels of these parameters chosen from the ranges proposed in applications, each loading lasts until the fracture occurs, and one of the tests contains an intermediate interval of total loading and repeated loading) and one axial shock compression test if there are dynamic problems in the applications. The model is based on the use of the criterion fracture parameter which, in the class of proportional loading processes, is the sum of partial increments of the strain

  20. Accumulation of polybrominated diphenyl ethers in the brain compared with the levels in other tissues among different vertebrates from an e-waste recycling site.

    PubMed

    Zhao, Yaxian; Li, Yuanyuan; Qin, Xiaofei; Lou, Qinqin; Qin, Zhanfen

    2016-11-01

    This study aimed to investigate the accumulation of polybrominated diphenyl ethers (PBDEs) in the brain compared with that in other tissues among different vertebrates. We collected mice, chickens, ducks, frogs, and fish from an e-waste recycling region in Taizhou, China, and measured PBDE concentrations in brain, liver and muscle tissues. The levels of PBDE in the tissues of mice, chickens, ducks, frogs and fish ranged 0.45-206, 0.06-18.8, 1.83-112, 2.75-108, and 0.02-32.0 ng/g wet weight, respectively. Preferential distribution in the liver and muscle relative to the brain was observed for PBDEs in mice, chickens, ducks and frogs. However, a high retention in the brain compared to the liver and muscle was observed in fish. Comparison of the brain/liver concentration (B/L) ratios revealed differences in PBDEs accumulation in the brain among these vertebrates. PBDEs accumulation in the brain was greatest in fish, followed by frogs, while the lowest accumulation occurred in the brains of mammals and birds. The findings apparently coincided with the evolution of the blood-brain barrier (BBB) across vertebrates, i.e. the BBB of fish might be less efficient than those of mammals, birds and amphibian. Low brominated congeners (such as BDE-28, BDE-47 and BDE-99) were predominant in the brains of investigated vertebrates, whereas BDE-209 was most abundant in liver and muscle tissues of mice, chickens and ducks. Significant differences in B/L ratios among PBDE congeners were found in both mice and chickens (p < 0.05). Particularly in mice, the B/L ratios of PBDE congeners presented a declining trend with increased bromine number. Our findings suggested that low brominated congeners might have a higher capacity to penetrate the BBB and accumulate in the brain, whereas high brominated congeners such as BDE-209 might have less potency to pass through the barrier. Further experimental studies are needed to confirm our findings. Copyright © 2016 Elsevier Ltd. All rights

  1. Systems Level Regulation of Rhythmic Growth Rate and Biomass Accumulation in Grasses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kay, Steve A.; Hazen, Samuel; Mullet, John

    Critical to the development of renewable energy sources from biofuels is the improvement of biomass from energy feedstocks, such as sorghum and maize. The specific goals of this project include 1) characterize the growth and gene expression patterns under diurnal and circadian conditions, 2) select transcription factors associated with growth and build a cis-regulatory network in yeast, and 3) perturb these transcription factors in planta using transgenic Brachypodium and sorghum, and characterize the phenotypic outcomes as they relate to biomass accumulation. A better understanding of diurnally regulated growth behavior in grasses may lead to species-specific mechanisms highly relevant to futuremore » strategies to optimize energy crop biomass yield.« less

  2. Accumulation of secondary metabolites in healthy and diseased barley, grown under future climate levels of CO2, ozone and temperature.

    PubMed

    Mikkelsen, B L; Olsen, C E; Lyngkjær, M F

    2015-10-01

    Plants produce secondary metabolites promoting adaptation to changes in the environment and challenges by pathogenic microorganisms. A future climate with increased temperature and CO2 and ozone levels will likely alter the chemical composition of plants and thereby plant-pathogen interactions. To investigate this, barley was grown at elevated CO2, temperature and ozone levels as single factors or in combination resembling future climatic conditions. Increased basal resistance to the powdery mildew fungus was observed when barley was grown under elevated CO2, temperature and ozone as single factors. However, this effect was neutralized in the combination treatments. Twenty-five secondary metabolites were putatively identified in healthy and diseased barley leaves, including phenylpropanoids, phenolamides and hydroxynitrile glucosides. Accumulation of the compounds was affected by the climatic growth conditions. Especially elevated temperature, but also ozone, showed a strong impact on accumulation of many compounds, suggesting that these metabolites play a role in adaptation to unfavorable growth conditions. Many compounds were found to increase in powdery mildew diseased leaves, in correlation with a strong and specific influence of the climatic growth conditions. The observed disease phenotypes could not be explained by accumulation of single compounds. However, decreased accumulation of the powdery mildew associated defense compound p-coumaroylhydroxyagmatine could be implicated in the increased disease susceptibility observed when barley was grown under combination of elevated CO2, temperature and ozone. The accumulation pattern of the compounds in both healthy and diseased leaves from barley grown in the combination treatments could not be deduced from the individual single factor treatments. This highlights the complex role and regulation of secondary metabolites in plants' adaptation to unfavorable growth conditions. Copyright © 2015 Elsevier Ltd. All

  3. High CO2 levels impair alveolar epithelial function independently of pH.

    PubMed

    Briva, Arturo; Vadász, István; Lecuona, Emilia; Welch, Lynn C; Chen, Jiwang; Dada, Laura A; Trejo, Humberto E; Dumasius, Vidas; Azzam, Zaher S; Myrianthefs, Pavlos M; Batlle, Daniel; Gruenbaum, Yosef; Sznajder, Jacob I

    2007-11-28

    In patients with acute respiratory failure, gas exchange is impaired due to the accumulation of fluid in the lung airspaces. This life-threatening syndrome is treated with mechanical ventilation, which is adjusted to maintain gas exchange, but can be associated with the accumulation of carbon dioxide in the lung. Carbon dioxide (CO2) is a by-product of cellular energy utilization and its elimination is affected via alveolar epithelial cells. Signaling pathways sensitive to changes in CO2 levels were described in plants and neuronal mammalian cells. However, it has not been fully elucidated whether non-neuronal cells sense and respond to CO2. The Na,K-ATPase consumes approximately 40% of the cellular metabolism to maintain cell homeostasis. Our study examines the effects of increased pCO2 on the epithelial Na,K-ATPase a major contributor to alveolar fluid reabsorption which is a marker of alveolar epithelial function. We found that short-term increases in pCO2 impaired alveolar fluid reabsorption in rats. Also, we provide evidence that non-excitable, alveolar epithelial cells sense and respond to high levels of CO2, independently of extracellular and intracellular pH, by inhibiting Na,K-ATPase function, via activation of PKCzeta which phosphorylates the Na,K-ATPase, causing it to endocytose from the plasma membrane into intracellular pools. Our data suggest that alveolar epithelial cells, through which CO2 is eliminated in mammals, are highly sensitive to hypercapnia. Elevated CO2 levels impair alveolar epithelial function, independently of pH, which is relevant in patients with lung diseases and altered alveolar gas exchange.

  4. Cadmium Accumulation Characteristics in Turnip Landraces from China and Assessment of Their Phytoremediation Potential for Contaminated Soils.

    PubMed

    Li, Xiong; Zhang, Xiaoming; Yang, Ya; Li, Boqun; Wu, Yuansheng; Sun, Hang; Yang, Yongping

    2016-01-01

    Heavy metal (HM) pollution is a global environmental problem that threatens ecosystem and human health. Cadmium (Cd) pollution is the most prominent HM pollution type because of its high toxicity, strong migration, and the large polluted area globally. Phytoremediation of contaminated soil is frequently practiced because of its cost-effectiveness and operability and because it has no associated secondary pollution. High-accumulation plants, including those identified as hyperaccumulators, play an important role in phytoremediation. Therefore, screening of plants to identify hyperaccumulators is important for continued phytoremediation. In the present study, we investigated the Cd tolerance and accumulation capabilities of 18 turnip landraces from China under a soil experiment with known Cd level. The results indicated that turnip has a high capacity for Cd accumulation. Furthermore, significant differences in Cd tolerance and accumulation characteristics were found among different landraces when they grew at 50 mg kg -1 (dry weight) Cd concentration. Among the studied landraces, five turnip landraces met the requirements of Cd hyperaccumulators and three landraces were identified as potential candidates. However, the total Cd content accumulated by individual plant of different turnip landraces was dependent on both the Cd accumulation capacity and plant biomass. Compared with some reported Cd hyperaccumulators, turnip not only shows a high Cd-accumulation capacity but also has rapid growth and a wide distribution area. These advantages indicate that turnip may have considerable potential for phytoremediation of Cd-contaminated soil. Furthermore, the study also indicates that it is not advisable to consume turnip cultivated in an environment that exceeds safe Cd levels.

  5. Marine CDOM accumulation during a coastal Arctic mesocosm experiment: No response to elevated pCO2 levels

    NASA Astrophysics Data System (ADS)

    Pavlov, Alexey K.; Silyakova, Anna; Granskog, Mats A.; Bellerby, Richard G. J.; Engel, Anja; Schulz, Kai G.; Brussaard, Corina P. D.

    2014-06-01

    A large-scale multidisciplinary mesocosm experiment in an Arctic fjord (Kongsfjorden, Svalbard; 78°56.2'N) was used to study Arctic marine food webs and biogeochemical elements cycling at natural and elevated future carbon dioxide (CO2) levels. At the start of the experiment, marine-derived chromophoric dissolved organic matter (CDOM) dominated the CDOM pool. Thus, this experiment constituted a convenient case to study production of autochthonous CDOM, which is typically masked by high levels of CDOM of terrestrial origin in the Arctic Ocean proper. CDOM accumulated during the experiment in line with an increase in bacterial abundance; however, no response was observed to increased pCO2 levels. Changes in CDOM absorption spectral slopes indicate that bacteria were most likely responsible for the observed CDOM dynamics. Distinct absorption peaks (at 330 and 360 nm) were likely associated with mycosporine-like amino acids (MAAs). Due to the experimental setup, MAAs were produced in absence of ultraviolet exposure providing evidence for MAAs to be considered as multipurpose metabolites rather than simple photoprotective compounds. We showed that a small increase in CDOM during the experiment made it a major contributor to total absorption in a range of photosynthetically active radiation (PAR, 400-700 nm) and, therefore, is important for spectral light availability and may be important for photosynthesis and phytoplankton groups composition in a rapidly changing Arctic marine ecosystem.

  6. Effect of cadmium accumulation on mineral nutrient levels in vegetable crops: potential implications for human health.

    PubMed

    Yang, Danping; Guo, Zhiqiang; Green, Iain D; Xie, Deti

    2016-10-01

    Consumption of vegetables is often the predominant route whereby humans are exposed to the toxic metal Cd. Health impacts arising from Cd consumption may be influenced by changes in the mineral nutrient content of vegetables, which may occur when plants are exposed to Cd. Here, we subjected model root (carrot) and leaf (lettuce) vegetables to soil Cd concentrations of 0.3, 1.5, 3.3, and 9.6 μg g(-1) for 10 weeks to investigate the effect of Cd exposure on Cd accumulation, growth performance, and mineral nutrient homeostasis. The findings demonstrated that Cd accumulation in lettuce (20.1-71.5 μg g(-1)) was higher than that in carrot (3.2-27.5 μg g(-1)), and accumulation exceeded the maximum permissible Cd concentration in vegetables when soil contained more than 3.3 μg g(-1) of Cd. There was a marked hormetic effect on carrot growth at a soil Cd concentration of 3.3 μg g(-1), but increasing the Cd concentration to 9.6 μg g(-1) caused decreased growth in both crops. Additionally, in most cases, there was a positive correlation between Cd and the mineral nutrient content of vegetables, which was due to physiological changes in the plants causing increased uptake and/or translocation. This may suggest a general mechanism whereby the plant compensated for disrupted mineral nutrient metabolism by increasing nutrient supply to its tissues. Increased nutrient levels could potentially offset some risks posed to humans by increased Cd levels in crops, and we therefore suggest that changes in mineral nutrient levels should be included more widely in the risk assessment of potentially toxic metal contamination. Graphical abstract The Cd concentration (μg g-1 in dry matter) in the root, shoot and translocation factor (TF) of Cd from root to shoot in the carrot and lettuce, and the percentage of root Cd to the gross Cd contents (%) in carrot (C) and lettuce (D) exposed to soil Cd (0 (control), 1, 3, and 9 μg g-1) for 70 days. Values are means ± SD (n = 5).

  7. SU-E-T-315: The Change of Optically Stimulated Luminescent Dosimeters (OSLDs) Sensitivity by Accumulated Dose and High Dose

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Han, S; Jung, H; Kim, M

    2014-06-01

    Purpose: The objective of this study is to evaluate radiation sensitivity of optical stimulated luminance dosimeters (OSLDs) by accumulated dose and high dose. Methods: This study was carried out in Co-60 unit (Theratron 780, AECL, and Canada) and used InLight MicroStar reader (Landauer, Inc., Glenwood, IL) for reading. We annealed for 30 min using optical annealing system which contained fluorescent lamps (Osram lumilux, 24 W, 280 ∼780 nm). To evaluate change of OSLDs sensitivity by repeated irradiation, the dosimeters were repeatedly irradiated with 1 Gy. And whenever a repeated irradiation, we evaluated OSLDs sensitivity. To evaluate OSLDs sensitivity after accumulatedmore » dose with 5 Gy, We irradiated dose accumulatively (from 1 Gy to 5 Gy) without annealing. And OSLDs was also irradiated with 15, 20, 30 Gy to certify change of OSLDs sensitivity after high dose irradiation. After annealing them, they were irradiated with 1Gy, repeatedly. Results: The OSLDs sensitivity increased up to 3% during irradiating seven times and decreased continuously above 8 times. That dropped by about 0.35 Gy per an irradiation. Finally, after 30 times irradiation, OSLDs sensitivity decreased by about 7%. For accumulated dose from 1 Gy to 5 Gy, OSLDs sensitivity about 1 Gy increased until 4.4% after second times accumulated dose compared with before that. OSLDs sensitivity about 1 Gy decreased by 1.6% in five times irradiation. When OSLDs were irradiated ten times with 1Gy after irradiating high dose (10, 15, 20 Gy), OSLDs sensitivity decreased until 6%, 9%, 12% compared with it before high dose irradiation, respectively. Conclusion: This study certified OSLDs sensitivity by accumulated dose and high dose. When irradiated with 1Gy, repeatedly, OSLDs sensitivity decreased linearly and the reduction rate of OSLDs sensitivity after high dose irradiation had dependence on irradiated dose.« less

  8. Alteration of respiration capacity and transcript accumulation level of alternative oxidase genes in necrosis lines of common wheat.

    PubMed

    Sugie, Atsushi; Murai, Koji; Takumi, Shigeo

    2007-06-01

    Mitochondrial alternative oxidase (AOX) is the terminal oxidase responsible for cyanide-insensitive and salicylhydroxamic acid-sensitive respiration in plants. AOX is a key enzyme of the alternative respiration pathway. To study the effects of necrotic cell death on the mitochondrial function, production of reactive oxygen species (ROS), respiration capacities and accumulation patterns of mitochondria-targeted protein-encoding gene transcripts were compared between wild-type, lesion-mimic mutant and hybrid necrosis wheat plants. Around cells with the necrosis symptom, ROS accumulated abundantly in the intercellular spaces. The ratio of the alternative pathway to the cytochrome pathway was markedly enhanced in the necrotic leaves. Transcripts of a wheat AOX gene, Waox1a, were more abundant in a novel lesion-mimic mutant of common wheat than in the wild-type plants. An increased level of the Waox1a transcripts was also observed in hybrid plants containing Ne1 and Ne2 genes. These results indicated that an increase of the wheat AOX transcript level resulted in enhancement of respiration capacity of the alternative pathway in the necrotic cells.

  9. Age-related accumulation of the advanced glycation endproduct pentosidine in human articular cartilage aggrecan: the use of pentosidine levels as a quantitative measure of protein turnover.

    PubMed

    Verzijl, N; DeGroot, J; Bank, R A; Bayliss, M T; Bijlsma, J W; Lafeber, F P; Maroudas, A; TeKoppele, J M

    2001-11-01

    During aging, non-enzymatic glycation results in the formation and accumulation of the advanced glycation endproduct pentosidine in long-lived proteins, such as articular cartilage collagen. In the present study, we investigated whether pentosidine accumulation also occurs in cartilage aggrecan. Furthermore, pentosidine levels in aggrecan subfractions of different residence time were used to explore pentosidine levels as a quantitative measure of aggrecan turnover. In order to compare protein turnover rates, protein residence time was measured as racemization of aspartic acid. As has previously been shown for collagen, pentosidine levels increase with age in cartilage aggrecan. Consistent with the faster turnover of aggrecan compared to collagen, the rate of pentosidine accumulation was threefold lower in aggrecan than in collagen. In the subfractions of aggrecan, pentosidine levels increased with protein residence time. These pentosidine levels were used to estimate the half-life of the globular hyaluronan-binding domain of aggrecan to be 19.5 years. This value is in good agreement with the half-life of 23.5 years that was estimated based on aspartic acid racemization. In aggrecan from osteoarthritic (OA) cartilage, decreased pentosidine levels were found compared with normal cartilage, which reflects increased aggrecan turnover during the OA disease process. In conclusion, we showed that pentosidine accumulates with age in aggrecan and that pentosidine levels can be used as a measure of turnover of long-lived proteins, both during normal aging and during disease.

  10. Effects of exposure to high glucose on primary cultured hippocampal neurons: involvement of intracellular ROS accumulation.

    PubMed

    Liu, Di; Zhang, Hong; Gu, Wenjuan; Zhang, Mengren

    2014-06-01

    Recent studies showed that hyperglycemia is the main trigger of diabetic cognitive impairment and can cause hippocampus abnormalities. The goal of this study is to explore the effects of different concentrations of high glucose for different exposure time on cell viability as well as intracellular reactive oxygen species (ROS) generation of primary cultured hippocampal neurons. Hippocampal neurons were exposed to different concentrations of high glucose (50, 75, 100, 125, and 150 mM) for 24, 48, 72 and 96 h. Cell viability and nuclear morphology were evaluated by MTT and Hoechst assays, respectively. Intracellular ROS were monitored using the fluorescent probe DCFH-DA. The results showed that, compared with control group, the cell viability of all high glucose-treated groups decreased significantly after 72 h and there also was a significant increase of apoptotic nuclei in high glucose-treated groups from 72 to 96 h. Furthermore, 50 mM glucose induced a peak rise in ROS generation at 24 h and the intracellular ROS levels of 50 mM glucose group were significantly higher than the corresponding control group from 6 to 72 h. These results suggest that hippocampal neurons could be injured by high glucose exposure and the neuronal injury induced by high glucose is potentially mediated through intracellular ROS accumulation.

  11. Carotenoid accumulation in orange-pigmented Capsicum annuum fruit, regulated at multiple levels.

    PubMed

    Rodriguez-Uribe, Laura; Guzman, Ivette; Rajapakse, Wathsala; Richins, Richard D; O'Connell, Mary A

    2012-01-01

    The pericarp of Capsicum fruit is a rich dietary source of carotenoids. Accumulation of these compounds may be controlled, in part, by gene transcription of biosynthetic enzymes. The carotenoid composition in a number of orange-coloured C. annuum cultivars was determined using HPLC and compared with transcript abundances for four carotenogenic enzymes, Psy, LcyB, CrtZ-2, and Ccs determined by qRT-PCR. There were unique carotenoid profiles as well as distinct patterns of transcription of carotenogenic enzymes within the seven orange-coloured cultivars. In one cultivar, 'Fogo', carrying the mutant ccs-3 allele, transcripts were detected for this gene, but no CCS protein accumulated. The premature stop termination in ccs-3 prevented expression of the biosynthetic activity to synthesize the capsanthin and capsorubin forms of carotenoids. In two other orange-coloured cultivars, 'Orange Grande' and 'Oriole', both with wild-type versions of all four carotenogenic enzymes, no transcripts for Ccs were detected and no red pigments accumulated. Finally, in a third case, the orange-coloured cultivar, Canary, transcripts for all four of the wild-type carotenogenic enzymes were readily detected yet no CCS protein appeared to accumulate and no red carotenoids were synthesized. In the past, mutations in Psy and Ccs have been identified as the loci controlling colour in the fruit. Now there is evidence that a non-structural gene may control colour development in Capsicum.

  12. Enhanced accumulation of adipocytes in bone marrow stromal cells in the presence of increased extracellular and intracellular [Ca{sup 2+}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashimoto, Ryota, E-mail: hryota@juntendo.ac.jp; Katoh, Youichi, E-mail: katoyo@juntendo-urayasu.jp; Nakamura, Kyoko

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer High [Ca{sup 2+}]{sub o} enhances adipocyte accumulation in the presence of adipogenic inducers. Black-Right-Pointing-Pointer High [Ca{sup 2+}]{sub o} enhances both proliferation and adipocyte differentiation in BMSCs. Black-Right-Pointing-Pointer High [Ca{sup 2+}]{sub o} induces an increase in [Ca{sup 2+}]{sub o} in BMSCs. Black-Right-Pointing-Pointer An intracellular Ca{sup 2+} chelator suppresses the enhancement in adipocyte accumulation. Black-Right-Pointing-Pointer Controlling [Ca{sup 2+}]{sub o} may govern the balance of adipocyte and osteoblast development. -- Abstract: The bone marrow stroma contains osteoblasts and adipocytes that have a common precursor: the pluripotent mesenchymal stem cell found in bone marrow stromal cells (BMSCs). Local bone marrow Ca{sup 2+}more » levels can reach high concentrations due to bone resorption, which is one of the notable features of the bone marrow stroma. Here, we describe the effects of high [Ca{sup 2+}]{sub o} on the accumulation of adipocytes in the bone marrow stroma. Using primary mouse BMSCs, we evaluated the level of adipocyte accumulation by measuring Oil Red O staining and glycerol-3-phosphate dehydrogenase (GPDH) activity. High [Ca{sup 2+}]{sub o} enhanced the accumulation of adipocytes following treatment with both insulin and dexamethasone together but not in the absence of this treatment. This enhanced accumulation was the result of both the accelerated proliferation of BMSCs and their differentiation into adipocytes. Using the fura-2 method, we also showed that high [Ca{sup 2+}]{sub o} induces an increase in [Ca{sup 2+}]{sub i}. An intracellular Ca{sup 2+} chelator suppressed the enhancement in adipocyte accumulation due to increased [Ca{sup 2+}]{sub o} in BMSCs. These data suggest a new role for extracellular Ca{sup 2+} in the bone marrow stroma: increased [Ca{sup 2+}]{sub o} induces an increase in [Ca{sup 2+}]{sub i} levels, which in turn enhances the

  13. Effects of Organic Selenium Supplementation on Growth, Accumulation, Haematology and Histopathology of Juvenile Barramundi (Lates calcarifer) Fed High Soybean Meal Diets.

    PubMed

    Ilham, Ilham; Siddik, Muhammad Abu Bakar; Fotedar, Ravi

    2016-12-01

    Soybean meal (SBM) has been commonly utilised as a substitute for fishmeal (FM) in the diets of several fish species. However, little is known regarding their effects on trace element availability and thus their importance to fish. The present study employed two feeding trials to evaluate the implications of dietary selenium (Se) on the growth, accumulation, antioxidant, and histopathological responses of juvenile barramundi (Lates calcarifer). In the first trial, each of three basal diets containing 0, 15 and 43 % SBM as replacements for 0, 25 and 75 % of FM protein on an isoproteic and isocalorific basis were either supplemented or not supplemented with 2 mg kg -1 organic Se (OS). In the second trial, the potential effect of OS supplementation in a high SBM diet was investigated in a feeding trial with five experimental diets: 75 % SBM protein as replacement of FM was supplemented with 2, 3, 4, 5 or 7 mg OS kg -1 . Growth was independently influenced by the SBM level and the OS supplementation level but not by their interaction. Glutathione peroxidase (GPx) activity, haematocrit, Se accumulation and muscle tissue integrity were significantly enhanced in fish fed on OS-supplemented diets. Furthermore, when high SBM was included in diets, elevated Se tended to lower the barramundi's performance. These findings suggest that dietary supplementation of OS at 2-3 g kg -1 diet is necessary when high plant protein ingredients are incorporated in the diet, in order to maintain better growth and to afford protection against oxidative stress.

  14. Regulation of carotenoid and ABA accumulation during the development and germination of Nicotiana plumbaginifolia seeds.

    PubMed

    Frey, Anne; Boutin, Jean-Pierre; Sotta, Bruno; Mercier, Raphaël; Marion-Poll, Annie

    2006-08-01

    Abscisic acid (ABA) is derived from epoxycarotenoid cleavage and regulates seed development and maturation. A detailed carotenoid analysis was undertaken to study the contribution of epoxycarotenoid synthesis to the regulation of ABA accumulation in Nicotiana plumbaginifolia developing seeds. Maximal accumulation of xanthophylls occurred at mid-development in wild type seeds, when total ABA levels also peaked. In contrast, in ABA-deficient mutants xanthophyll synthesis was delayed, in agreement with the retardation in seed maturation. Seed dormancy was restored in mutants impaired in the conversion of zeaxanthin into violaxanthin by zeaxanthin epoxidase (ZEP), by the introduction of the Arabidopsis AtZEP gene under the control of promoters inducing expression during later stages of seed development compared to wild type NpZEP, and in dry and imbibed seeds. Alterations in the timing and level of ZEP expression did not highly affect the temporal regulation of ABA accumulation in transgenic seeds, despite notable perturbations in xanthophyll accumulation. Therefore, major regulatory control of ABA accumulation might occur downstream of epoxycarotenoid synthesis.

  15. Brassinosteroid-Insensitive Dwarf Mutants of Arabidopsis Accumulate Brassinosteroids1

    PubMed Central

    Noguchi, Takahiro; Fujioka, Shozo; Choe, Sunghwa; Takatsuto, Suguru; Yoshida, Shigeo; Yuan, Heng; Feldmann, Kenneth A.; Tax, Frans E.

    1999-01-01

    Seven dwarf mutants resembling brassinosteroid (BR)-biosynthetic dwarfs were isolated that did not respond significantly to the application of exogenous BRs. Genetic and molecular analyses revealed that these were novel alleles of BRI1 (Brassinosteroid-Insensitive 1), which encodes a receptor kinase that may act as a receptor for BRs or be involved in downstream signaling. The results of morphological and molecular analyses indicated that these represent a range of alleles from weak to null. The endogenous BRs were examined from 5-week-old plants of a null allele (bri1-4) and two weak alleles (bri1-5 and bri1-6). Previous analysis of endogenous BRs in several BR-biosynthetic dwarf mutants revealed that active BRs are deficient in these mutants. However, bri1-4 plants accumulated very high levels of brassinolide, castasterone, and typhasterol (57-, 128-, and 33-fold higher, respectively, than those of wild-type plants). Weaker alleles (bri1-5 and bri1-6) also accumulated considerable levels of brassinolide, castasterone, and typhasterol, but less than the null allele (bri1-4). The levels of 6-deoxoBRs in bri1 mutants were comparable to that of wild type. The accumulation of biologically active BRs may result from the inability to utilize these active BRs, the inability to regulate BR biosynthesis in bri1 mutants, or both. Therefore, BRI1 is required for the homeostasis of endogenous BR levels. PMID:10557222

  16. Gypsum accumulation on carbonate stone

    USGS Publications Warehouse

    McGee, E.S.; Mossotti, V.G.

    1992-01-01

    The accumulation of gypsum on carbonate stone has been investigated through exposure of fresh samples of limestone and marble at monitored sites, through examination of alteration crusts from old buildings and through laboratory experiments. Several factors contribute to gypsum accumulation on carbonate stone. Marble or limestone that is sheltered from direct washing by rain in an urban environment with elevated pollution levels is likely to accumulate a gypsum crust. Crust development may be enhanced if the stone is porous or has an irregular surface area. Gypsum crusts are a surficial alteration feature; gypsum crystals form at the pore opening-air interface, where evaporation is greatest.

  17. Sugar loss and enzyme inhibition due to oligosaccharides accumulation during high solids-loading enzymatic hydrolysis

    USDA-ARS?s Scientific Manuscript database

    Oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, ammonia fiber expansion: AFEX and extractive ammonia: EA). The methodology for large-scale separation of ...

  18. Carotenoid accumulation in orange-pigmented Capsicum annuum fruit, regulated at multiple levels

    PubMed Central

    Rodriguez-Uribe, Laura; Guzman, Ivette; Rajapakse, Wathsala; Richins, Richard D.; O’Connell, Mary A.

    2012-01-01

    The pericarp of Capsicum fruit is a rich dietary source of carotenoids. Accumulation of these compounds may be controlled, in part, by gene transcription of biosynthetic enzymes. The carotenoid composition in a number of orange-coloured C. annuum cultivars was determined using HPLC and compared with transcript abundances for four carotenogenic enzymes, Psy, LcyB, CrtZ-2, and Ccs determined by qRT-PCR. There were unique carotenoid profiles as well as distinct patterns of transcription of carotenogenic enzymes within the seven orange-coloured cultivars. In one cultivar, ‘Fogo’, carrying the mutant ccs-3 allele, transcripts were detected for this gene, but no CCS protein accumulated. The premature stop termination in ccs-3 prevented expression of the biosynthetic activity to synthesize the capsanthin and capsorubin forms of carotenoids. In two other orange-coloured cultivars, ‘Orange Grande’ and ‘Oriole’, both with wild-type versions of all four carotenogenic enzymes, no transcripts for Ccs were detected and no red pigments accumulated. Finally, in a third case, the orange-coloured cultivar, Canary, transcripts for all four of the wild-type carotenogenic enzymes were readily detected yet no CCS protein appeared to accumulate and no red carotenoids were synthesized. In the past, mutations in Psy and Ccs have been identified as the loci controlling colour in the fruit. Now there is evidence that a non-structural gene may control colour development in Capsicum. PMID:21948863

  19. Semirational Approach for Ultrahigh Poly(3-hydroxybutyrate) Accumulation in Escherichia coli by Combining One-Step Library Construction and High-Throughput Screening.

    PubMed

    Li, Teng; Ye, Jianwen; Shen, Rui; Zong, Yeqing; Zhao, Xuejin; Lou, Chunbo; Chen, Guo-Qiang

    2016-11-18

    As a product of a multistep enzymatic reaction, accumulation of poly(3-hydroxybutyrate) (PHB) in Escherichia coli (E. coli) can be achieved by overexpression of the PHB synthesis pathway from a native producer involving three genes phbC, phbA, and phbB. Pathway optimization by adjusting expression levels of the three genes can influence properties of the final product. Here, we reported a semirational approach for highly efficient PHB pathway optimization in E. coli based on a phbCAB operon cloned from the native producer Ralstonia entropha (R. entropha). Rationally designed ribosomal binding site (RBS) libraries with defined strengths for each of the three genes were constructed based on high or low copy number plasmids in a one-pot reaction by an oligo-linker mediated assembly (OLMA) method. Strains with desired properties were evaluated and selected by three different methodologies, including visual selection, high-throughput screening, and detailed in-depth analysis. Applying this approach, strains accumulating 0%-92% PHB contents in cell dry weight (CDW) were achieved. PHB with various weight-average molecular weights (M w ) of 2.7-6.8 × 10 6 were also efficiently produced in relatively high contents. These results suggest that the semirational approach combining library design, construction, and proper screening is an efficient way to optimize PHB and other multienzyme pathways.

  20. Predicting Regional Pattern of Longitudinal β-Amyloid Accumulation by Baseline PET.

    PubMed

    Guo, Tengfei; Brendel, Matthias; Grimmer, Timo; Rominger, Axel; Yakushev, Igor

    2017-04-01

    Knowledge about spatial and temporal patterns of β-amyloid (Aβ) accumulation is essential for understanding Alzheimer disease (AD) and for design of antiamyloid drug trials. Here, we tested whether the regional pattern of longitudinal Aβ accumulation can be predicted by baseline amyloid PET. Methods: Baseline and 2-y follow-up 18 F-florbetapir PET data from 58 patients with incipient and manifest dementia due to AD were analyzed. With the determination of how fast amyloid deposits in a given region relative to the whole-brain gray matter, a pseudotemporal accumulation rate for each region was calculated. The actual accumulation rate of 18 F-florbetapir was calculated from follow-up data. Results: Pseudotemporal measurements from baseline PET data explained 87% ( P < 0.001) of the variance in longitudinal accumulation rate across 62 regions. The method accurately predicted the top 10 fast and slow accumulating regions. Conclusion: Pseudotemporal analysis of baseline PET images is capable of predicting the regional pattern of longitudinal Aβ accumulation in AD at a group level. This approach may be useful in exploring spatial patterns of Aβ accumulation in other amyloid-associated disorders such as Lewy body disease and atypical forms of AD. In addition, the method allows identification of brain regions with a high accumulation rate of Aβ, which are of particular interest for antiamyloid clinical trials. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  1. Boron accumulation by Lemna minor L. under salt stress.

    PubMed

    Liu, Chunguang; Gu, Wancong; Dai, Zheng; Li, Jia; Jiang, Hongru; Zhang, Qian

    2018-06-12

    Excess boron (B) is toxic to aquatic organisms and humans. Boron is often present in water with high salinity. To evaluate the potential of duckweed (Lemna minor L.) for removing B from water under salt stress, we cultured duckweed in water with 2 mg/L of B and sodium chloride (NaCl) concentrations ranging from 0 to 200 mM for 4 days. The results show that with increasing salinity, the capacity of L. minor to accumulate B initially decreased and then increased. L. minor used different mechanisms to accumulate boron at lower and higher levels of salt stress. The growth and chlorophyll synthesis of L. minor were significantly inhibited when the concentration of NaCl reached 100 mM. Our results suggest that L. minor is suitable for the accumulation of B when NaCl salinity is below 100 mM.

  2. What characterizes persons with high levels of perceived stress in Denmark? A national representative study.

    PubMed

    Nielsen, Line; Curtis, Tine; Kristensen, Tage S; Rod Nielsen, Naja

    2008-06-01

    Stress is a growing public health problem, but there are only a few studies with national representative samples on the occurrence of stress. The aim of this study was to assess the level of stress, measured by the Perceived Stress Scale, in Denmark, and to identify and characterize the group with high levels of stress by factors measured at both the individual and neighbourhood levels in a national representative sample of the Danish population. The 10,022 participants in the National Health Interview Survey 2005 were asked about perceived stress and individual factors in a cross-sectional design. Information on neighbourhood factors was derived from a national registry. Data were analysed by means of logistic regression models. Low education, heavy smoking, physical inactivity, lack of social network and poor working conditions were associated with perceived stress. For women, living in a neighbourhood with low average education, and for men, living in a neighbourhood with a high rate of crime and a low degree of ethnic diversity, were associated with higher perceived stress. Perceived stress was also related to indicators of morbidity. The group with high perceived stress is characterized by individual and neighbourhood factors with negative impacts on quality of life and risk of illness. This knowledge can guide future stress prevention efforts. Additionally, the results suggest a negative social component where perceived stress, unhealthy lifestyle and low social status are accumulated, and perceived stress might be used as a measure to identify groups characterized by accumulation of risk factors.

  3. Slow Cortical Dynamics and the Accumulation of Information over Long Timescales

    PubMed Central

    Honey, Christopher J.; Thesen, Thomas; Donner, Tobias H.; Silbert, Lauren J.; Carlson, Chad E.; Devinsky, Orrin; Doyle, Werner K.; Rubin, Nava; Heeger, David J.; Hasson, Uri

    2012-01-01

    SUMMARY Making sense of the world requires us to process information over multiple timescales. We sought to identify brain regions that accumulate information over short and long timescales and to characterize the distinguishing features of their dynamics. We recorded electrocorticographic (ECoG) signals from individuals watching intact and scrambled movies. Within sensory regions, fluctuations of high-frequency (64–200 Hz) power reliably tracked instantaneous low-level properties of the intact and scrambled movies. Within higher order regions, the power fluctuations were more reliable for the intact movie than the scrambled movie, indicating that these regions accumulate information over relatively long time periods (several seconds or longer). Slow (<0.1 Hz) fluctuations of high-frequency power with time courses locked to the movies were observed throughout the cortex. Slow fluctuations were relatively larger in regions that accumulated information over longer time periods, suggesting a connection between slow neuronal population dynamics and temporally extended information processing. PMID:23083743

  4. Socioeconomic studies of high-level nuclear waste disposal.

    PubMed Central

    White, G F; Bronzini, M S; Colglazier, E W; Dohrenwend, B; Erikson, K; Hansen, R; Kneese, A V; Moore, R; Page, E B; Rappaport, R A

    1994-01-01

    The socioeconomic investigations of possible impacts of the proposed repository for high-level nuclear waste at Yucca Mountain, Nevada, have been unprecedented in several respects. They bear on the public decision that sooner or later will be made as to where and how to dispose permanently of the waste presently at military weapons installations and that continues to accumulate at nuclear power stations. No final decision has yet been made. There is no clear precedent from other countries. The organization of state and federal studies is unique. The state studies involve more disciplines than any previous efforts. They have been carried out in parallel to federal studies and have pioneered in defining some problems and appropriate research methods. A recent annotated bibliography provides interested scientists with a compact guide to the 178 published reports, as well as to relevant journal articles and related documents. PMID:7971963

  5. Arsenic accumulation in irrigated agricultural soils in Northern Greece.

    PubMed

    Casentini, B; Hug, S J; Nikolaidis, N P

    2011-10-15

    The accumulation of arsenic in soils and food crops due to the use of arsenic contaminated groundwater for irrigation has created worldwide concern. In the Chalkidiki prefecture in Northern Greece, groundwater As reach levels above 1000μg/L within the Nea Triglia geothermal area. While this groundwater is no longer used for drinking, it represents the sole source for irrigation. This paper provides a first assessment of the spatial extent of As accumulation and of As mobility during rainfall and irrigation periods. Arsenic content in sampled soils ranged from 20 to 513mg/kg inside to 5-66mg/kg outside the geothermal area. Around irrigation sprinklers, high As concentrations extended horizontally to distances of at least 1.5m, and to 50cm in depth. During simulated rain events in soil columns (pH=5, 0μg As/L), accumulated As was quite mobile, resulting in porewater As concentrations of 500-1500μg/L and exposing plant roots to high As(V) concentrations. In experiments with irrigation water (pH=7.5, 1500μg As/L), As was strongly retained (50.5-99.5%) by the majority of the soils. Uncontaminated soils (<30mg As/kg) kept soil porewater As concentrations to below 50μg/L. An estimated retardation factor R(f)=434 for weakly contaminated soil (<100mg/kg) indicates good ability to reduce As mobility. Highly contaminated soils (>500mg/kg) could not retain any of the added As. Invoked mechanisms affecting As mobility in those soils were adsorption on solid phases such as Fe/Mn-phases and As co-precipitation with Ca. Low As accumulation was found in collected olives (0.3-25μg/kg in flesh and 0.3-5.6μg/kg in pits). However, soil arsenic concentrations are frequently elevated to far above recommended levels and arsenic uptake in faster growing plants has to be assessed. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Accumulation of Flavonoid Glycosides and UFGT Gene Expression in Mulberry Leaves (Morus alba L.) before and after Frost.

    PubMed

    Yu, Xiaofeng; Zhu, Yiling; Fan, Jingyi; Wang, Dujun; Gong, Xiaohui; Ouyang, Zhen

    2017-08-01

    In order to determine the molecular mechanism underlying the influence of frost on chemical changes in mulberry leaves, the UFGT activity, expression level, and accumulation of flavonoid glycosides in mulberry leaves (Morus alba L.) were studied. The expression of UFGT gene was investigated by quantitative real-time PCR (qRT-PCR) and the UFGT activity, accumulation of flavonoid glycosides was studied by high performance liquid chromatography. Then, the correlation between the expression level of UFGT, the UFGT activity, and the flavonoid glycosides accumulation with temperature was explored. The accumulation of isoquercitrin and astragalin is significantly positively correlated with UFGT gene expression and UFGT activity. On the contrary, the average temperature was significantly negatively correlated with the level of UFGT gene expression and UFGT activity. The results show that after frost, low temperature can induce the expression of UFGT gene in mulberry leaves, resulting in the accumulation of flavonoid glycosides. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  7. Accumulation of Radioactive Cesium Released from Fukushima Daiichi Nuclear Power Plant in Terrestrial Cyanobacteria Nostoc commune

    PubMed Central

    Sasaki, Hideaki; Shirato, Susumu; Tahara, Tomoya; Sato, Kenji; Takenaka, Hiroyuki

    2013-01-01

    The Fukushima Daiichi Nuclear Power Plant accident released large amounts of radioactive substances into the environment and contaminated the soil of Tohoku and Kanto districts in Japan. Removal of radioactive material from the environment is an urgent problem, and soil purification using plants is being considered. In this study, we investigated the ability of 12 seed plant species and a cyanobacterium to accumulate radioactive material. The plants did not accumulate radioactive material at high levels, but high accumulation was observed in the terrestrial cyanobacterium Nostoc commune. In Nihonmatsu City, Fukushima Prefecture, N. commune accumulated 415,000 Bq/kg dry weight 134Cs and 607,000 Bq kg−1 dry weight 137Cs. The concentration of cesium in N. commune tended to be high in areas where soil radioactivity was high. A cultivation experiment confirmed that N. commune absorbed radioactive cesium from polluted soil. These data demonstrated that radiological absorption using N. commune might be suitable for decontaminating polluted soil. PMID:24256969

  8. Processes of contaminant accumulation in an Arctic beluga whale population

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hickie, B.E.; Muir, D.; Kingsley, M.

    1995-12-31

    As long-lived top predators in marine food chains, marine mammals accumulate high levels of persistent organic contaminants. While arctic marine mammal contaminant concentrations are lower than those from temperate regions, levels are sufficiently high to be a health concern to people who rely on marine mammals as food. Monitoring programs developed to address this problem and to define spatial and temporal trends often are difficult to interpret since tissue contaminant concentrations vary with species, age, sex, reproductive effort, and condition (ie blubber thickness). It can be difficult to relate contaminant concentrations in other environmental compartments to those in marine mammalsmore » since their residues reflect exposure over their entire life, often 20 to 30 years. Contaminant accumulation models for marine mammals enable us to better understand the importance of, and interaction between, factors affecting contaminant accumulation, and can provide a dynamic framework for interpreting contaminant monitoring data. The authors developed two models for the beluga whale (Delphinapterus leucas): one provides a detailed view of processes at the individual level, the other examines population-based processes. The models quantify uptake, release and disposition of organic contaminants over their entire lifespan by incorporating all aspects of life-history. These models are used together to examine impact of a variety of factors on patterns and variability of PCBs found in the West Greenland beluga population (sample size: 696, 729). Factors examined include: energetics, growth, birth rate, lactation, contaminant assimilation and clearance rates, and dietary contaminant concentrations. Results are discussed in relation to the use of marine mammals for monitoring contaminant trends.« less

  9. Impact of selenium supply on Se-methylselenocysteine and glucosinolate accumulation in selenium-biofortified Brassica sprouts.

    PubMed

    Avila, Fabricio William; Yang, Yong; Faquin, Valdemar; Ramos, Silvio Junio; Guilherme, Luiz Roberto G; Thannhauser, Theodore W; Li, Li

    2014-12-15

    Brassica sprouts are widely marketed as functional foods. Here we examined the effects of Se treatment on the accumulation of anticancer compound Se-methylselenocysteine (SeMSCys) and glucosinolates in Brassica sprouts. Cultivars from the six most extensively consumed Brassica vegetables (broccoli, cauliflower, green cabbage, Chinese cabbage, kale, and Brussels sprouts) were used. We found that Se-biofortified Brassica sprouts all were able to synthesize significant amounts of SeMSCys. Analysis of glucosinolate profiles revealed that each Brassica crop accumulated different types and amounts of glucosinolates. Cauliflower sprouts had high total glucosinolate content. Broccoli sprouts contained high levels of glucoraphanin, a precursor for potent anticancer compound. Although studies have reported an inverse relationship between accumulation of Se and glucosinolates in mature Brassica plants, Se supply generally did not affect glucosinolate accumulation in Brassica sprouts. Thus, Brassica vegetable sprouts can be biofortified with Se for the accumulation of SeMSCys without negative effects on chemopreventive glucosinolate contents. Published by Elsevier Ltd.

  10. TFH cells accumulate in mucosal tissues of humanized-DRAG mice and are highly permissive to HIV-1

    PubMed Central

    Allam, Atef; Majji, Sai; Peachman, Kristina; Jagodzinski, Linda; Kim, Jiae; Ratto-Kim, Silvia; Wijayalath, Wathsala; Merbah, Melanie; Kim, Jerome H.; Michael, Nelson L.; Alving, Carl R.; Casares, Sofia; Rao, Mangala

    2015-01-01

    CD4+ T follicular helper cells (TFH) in germinal centers are required for maturation of B-cells. While the role of TFH-cells has been studied in blood and lymph nodes of HIV-1 infected individuals, its role in the mucosal tissues has not been investigated. We show that the gut and female reproductive tract (FRT) of humanized DRAG mice have a high level of human lymphocytes and a high frequency of TFH (CXCR5+PD-1++) and precursor-TFH (CXCR5+PD-1+) cells. The majority of TFH-cells expressed CCR5 and CXCR3 and are the most permissive to HIV-1 infection. A single low-dose intravaginal HIV-1 challenge of humanized DRAG mice results in 100% infectivity with accumulation of TFH-cells mainly in the Peyer’s patches and FRT. The novel finding of TFH-cells in the FRT may contribute to the high susceptibility of DRAG mice to HIV-1 infection. This mouse model thus provides new opportunities to study TFH-cells and to evaluate HIV-1 vaccines. PMID:26034905

  11. Investigation of two-phase phenomena occurring within moisture separator reheater high-level reactor trips at the Maanshan nuclear power plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ferng, Y.M.; Liao, L.Y.

    1996-01-01

    During the operating history of the Maanshan nuclear power plant (MNPP), five reactor trips have occurred as a result of the moisture separator reheater (MSR) high-level signal. These MSR high-level reactor trips have been a very serious concern, especially during the startup period of MNPP. Consequently, studying the physical phenomena of this particular event is worthwhile, and analytical work is performed using the RELAP5/MOD3 code to investigate the thermal-hydraulic phenomena of two-phase behaviors occurring within the MSR high-level reactor trips. The analytical model is first assessed against the experimental data obtained from several test loops. The same model can thenmore » be applied with confidence to the study of this topic. According to the present calculated results, the phenomena of liquid droplet accumulation ad residual liquid blowing in the horizontal section of cross-under-lines can be modeled. In addition, the present model can also predict the different increasing rates of inlet steam flow rate affecting the liquid accumulation within the cross-under-lines. The calculated conclusion is confirmed by the revised startup procedure of MNPP.« less

  12. Ganoderic Acid A improves high fat diet-induced obesity, lipid accumulation and insulin sensitivity through regulating SREBP pathway.

    PubMed

    Zhu, Jing; Jin, Jie; Ding, Jiexia; Li, Siying; Cen, Panpan; Wang, Keyi; Wang, Hai; Xia, Junbo

    2018-06-25

    Obesity and its major co-morbidity, type 2 diabetes, have been an alarming epidemic prevalence without an effective treatment available. Sterol regulatory element-binding proteins (SREBPs) are major transcription factors regulating the expression of genes involved in biosynthesis of cholesterol, fatty acid and triglyceride. Therefore, inhibition of SREBP pathway may be a useful strategy to treat obesity with type 2 diabetes. Here, we identify a small molecule, Ganoderic Acid A (GAA), inhibits the SREBP expression and decreases the cellular levels of cholesterol and fatty acid in vitro. GAA also ameliorates body weight gain and fat accumulation in liver or adipose tissues, and improves serum lipid levels and insulin sensitivity in high fat diet (HFD)-induced obese mice. Consistently, GAA regulates SREBPs target genes and metabolism associated genes in liver or adipose tissues, which may directly contribute to the lower lipid level and improvement of insulin resistance. Taken together, GAA could be a potential leading compound for development of drugs for the prevention of obesity and insulin resistance. Copyright © 2018. Published by Elsevier B.V.

  13. Accumulation of methylglyoxal increases the advanced glycation end-product levels in DRG and contributes to lumbar disk herniation-induced persistent pain.

    PubMed

    Liu, Cui-Cui; Zhang, Xin-Sheng; Ruan, Yu-Ting; Huang, Zhu-Xi; Zhang, Su-Bo; Liu, Meng; Luo, Hai-Jie; Wu, Shao-Ling; Ma, Chao

    2017-08-01

    Lumbar disk herniation (LDH) with discogenic low back pain and sciatica is a common and complicated musculoskeletal disorder. The underlying mechanisms are poorly understood, and there are no effective therapies for LDH-induced pain. In the present study, we found that the patients who suffered from LDH-induced pain had elevated plasma methylglyoxal (MG) levels. In rats, implantation of autologous nucleus pulposus (NP) to the left lumbar 5 spinal nerve root, which mimicked LDH, induced mechanical allodynia, increased MG level in plasma and dorsal root ganglion (DRG), and enhanced the excitability of small DRG neurons (<30 μm in diameter). Intrathecal injection of MG also induced mechanical allodynia, and its application to DRG neurons ex vivo increased the number of action potentials evoked by depolarizing current pulses. Furthermore, inhibition of MG accumulation by aminoguanidine attenuated the enhanced excitability of small DRG neurons and the mechanical allodynia induced by NP implantation. In addition, NP implantation increased levels of advanced glycation end products (AGEs) in DRG, and intrathecal injection of MG-derived AGEs induced the mechanical allodynia and DRG neuronal hyperactivity. Intrathecal injection of MG also significantly increased the expression of AGEs in DRG. Importantly, scavenging of MG by aminoguanidine also attenuated the increase in AGEs induced by NP implantation. These results suggested that LDH-induced MG accumulation contributed to persistent pain by increasing AGE levels. Thus generation of AGEs from MG may represent a target for treatment of LDH-induced pain. NEW & NOTEWORTHY Our study demonstrates that methylglyoxal accumulation via increasing advanced glycation end-product levels in dorsal root ganglion contributes to the persistent pain induced by lumbar disk herniation, which proposed potential targets for the treatment of lumbar disk herniation-induced persistent pain. Copyright © 2017 the American Physiological Society.

  14. Accumulation of soluble sugars in peel at high temperature leads to stay-green ripe banana fruit.

    PubMed

    Yang, Xiaotang; Pang, Xuequn; Xu, Lanying; Fang, Ruiqiu; Huang, Xuemei; Guan, Peijian; Lu, Wangjin; Zhang, Zhaoqi

    2009-01-01

    Bananas (Musa acuminata, AAA group) fail to develop a yellow peel and stay green when ripening at temperatures >24 degrees C. The identification of the mechanisms leading to the development of stay-green ripe bananas has practical value and is helpful in revealing pathways involved in the regulation of chlorophyll (Chl) degradation. In the present study, the Chl degradation pathway was characterized and the progress of ripening and senescence was assessed in banana peel at 30 degrees C versus 20 degrees C, by monitoring relevant gene expression and ripening and senescence parameters. A marked reduction in the expression levels of the genes for Chl b reductase, SGR (Stay-green protein), and pheophorbide a oxygenase was detected for the fruit ripening at 30 degrees C, when compared with fruit at 20 degrees C, indicating that Chl degradation was repressed at 30 degrees C at various steps along the Chl catabolic pathway. The repressed Chl degradation was not due to delayed ripening and senescence, since the fruit at 30 degrees C displayed faster onset of various ripening and senescence symptoms, suggesting that the stay-green ripe bananas are of similar phenotype to type C stay-green mutants. Faster accumulation of high levels of fructose and glucose in the peel at 30 degrees C prompted investigation of the roles of soluble sugars in Chl degradation. In vitro incubation of detached pieces of banana peel showed that the pieces of peel stayed green when incubated with 150 mM glucose or fructose, but turned completely yellow in the absence of sugars or with 150 mM mannitol, at either 20 degrees C or 30 degrees C. The results suggest that accumulation of sugars in the peel induced by a temperature of 30 degrees C may be a major factor regulating Chl degradation independently of fruit senescence.

  15. Emodin ameliorates high-fat-diet induced insulin resistance in rats by reducing lipid accumulation in skeletal muscle.

    PubMed

    Cao, Yanni; Chang, Shufang; Dong, Jie; Zhu, Shenyin; Zheng, Xiaoying; Li, Juan; Long, Rui; Zhou, Yuanda; Cui, Jianyu; Zhang, Ye

    2016-06-05

    Emodin, an anthraquinone derivative isolated from root and rhizome of Rheum palmatum, has been reported to have promising anti-diabetic activity. The present study was to explore the possible mechanism of emodin to ameliorate insulin resistance. Insulin resistance was induced by feeding a high fat diet to Sprague-Dawley rats. The blood glucose and lipid profiles in serum were measured by an enzymatic method, and a hyperinsulinaemic-euglycaemic clamp was used to evaluate insulin resistance. L6 cells were cultured and treated with palmitic acid and emodin. The lipid content was assayed in the soleus muscle and L6 cells by Oil Red O staining. Western blot, qRT-PCR, and immunohistochemical staining were used to detect the following in the rat soleus muscle and L6 cells: protein levels, mRNA levels of FATP1, FATP4, transporter fatty acid translocase (FAT/CD36), and plasma membrane-associated fatty acid protein (FABPpm). We found that blood glucose, triglyceride (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly decreased in the emodin group. Oil Red O staining and the level of TG in skeletal muscle and L6 cells confirmed that lipid deposition decreased after treatment with emodin. Furthermore, the protein levels and mRNA levels of FATP1 in skeletal muscle and in L6 cells of rats were significantly decreased, yet the protein levels and mRNA levels of FATP4, FAT/CD36 and FABPpm did not drop off significantly. The study suggest that emodin ameliorates insulin resistance by reducing FATP1-mediated skeletal muscle lipid accumulation in rats fed a high fat diet. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Cinnamaldehyde supplementation prevents fasting-induced hyperphagia, lipid accumulation, and inflammation in high-fat diet-fed mice.

    PubMed

    Khare, Pragyanshu; Jagtap, Sneha; Jain, Yachna; Baboota, Ritesh K; Mangal, Priyanka; Boparai, Ravneet K; Bhutani, Kamlesh K; Sharma, Shyam S; Premkumar, Louis S; Kondepudi, Kanthi K; Chopra, Kanwaljit; Bishnoi, Mahendra

    2016-01-01

    Cinnamaldehyde, a bioactive component of cinnamon, is increasingly gaining interest for its preventive and therapeutic effects against metabolic complications like type-2 diabetes. This study is an attempt to understand the effect of cinnamaldehyde in high-fat diet (HFD)-associated increase in fasting-induced hyperphagia and related hormone levels, adipose tissue lipolysis and inflammation, and selected cecal microbial count in mice. Cinnamaldehyde, at 40 µM dose, prevented lipid accumulation and altered gene expression toward lipolytic phenotype in 3T3-L1 preadipocyte cell lines. In vivo, cinnamaldehyde coadministration prevented HFD-induced body weight gain, decreased fasting-induced hyperphagia, as well as circulating leptin and leptin/ghrelin ratio. In addition to that, cinnamaldehyde altered serum biochemical parameters related to lipolysis, that is, glycerol and free fatty acid levels. At transcriptional level, cinnamaldehyde increased anorectic gene expression in hypothalamus and lipolytic gene expression in visceral white adipose tissue. Furthermore, cinnamaldehyde also decreased serum IL-1β and inflammatory gene expression in visceral white adipose tissue. However, cinnamaldehyde did not modulate the population of selected gut microbial (Lactobacillus, Bifidibaceria, and Roseburia) count in cecal content. In conclusion, cinnamaldehyde increased adipose tissue lipolysis, decreased fasting-induced hyperphagia, normalized circulating levels of leptin/ghrelin ratio, and reduced inflammation in HFD-fed mice, which augurs well for its antiobesity role. © 2016 International Union of Biochemistry and Molecular Biology.

  17. Genotype variations in cadmium and lead accumulations of leafy lettuce (Lactuca sativa L.) and screening for pollution-safe cultivars for food safety.

    PubMed

    Zhang, Kun; Yuan, Jiangang; Kong, Wei; Yang, Zhongyi

    2013-06-01

    Heavy-metals in polluted soils can accumulate in plants and threaten crop safety. To evaluate the risk of heavy-metal pollution in leafy lettuce (Lactuca sativa L.), two pot experiments were conducted to investigate Cd and Pb accumulation and transfer potential in 28 cultivars of lettuce and to screen for low-Cd and low-Pb accumulative cultivars. In the three treatments, 5.2-fold, 4.8-fold and 4.8-fold differences in the shoot Cd concentration were observed between the cultivars with the highest and the lowest Cd concentrations, respectively. This genotype variation was sufficiently large to identify low-Cd accumulative genotypes to reduce Cd contamination in food. Cadmium accumulation in the low-Cd accumulative genotypes was significantly positively correlated with Pb accumulation. At the cultivar level, Cd and Pb accumulation in lettuce was stable and genotype-dependent. High Pb soil levels did not affect shoot Cd accumulation in lettuce. Lettuce was concluded to be at high risk for Cd pollution and low risk for Pb pollution. Among the tested cultivars, cvs. SJGT, YLGC, N518, and KR17 had the lowest Cd and Pb accumulation abilities in shoots and are thus important parental material for breeding pollution-safe cultivars to minimize Cd and Pb accumulation.

  18. Nuclear accumulation and activation of p53 in embryonic stem cells after DNA damage.

    PubMed

    Solozobova, Valeriya; Rolletschek, Alexandra; Blattner, Christine

    2009-06-17

    P53 is a key tumor suppressor protein. In response to DNA damage, p53 accumulates to high levels in differentiated cells and activates target genes that initiate cell cycle arrest and apoptosis. Since stem cells provide the proliferative cell pool within organisms, an efficient DNA damage response is crucial. In proliferating embryonic stem cells, p53 is localized predominantly in the cytoplasm. DNA damage-induced nuclear accumulation of p53 in embryonic stem cells activates transcription of the target genes mdm2, p21, puma and noxa. We observed bi-phasic kinetics for nuclear accumulation of p53 after ionizing radiation. During the first wave of nuclear accumulation, p53 levels were increased and the p53 target genes mdm2, p21 and puma were transcribed. Transcription of noxa correlated with the second wave of nuclear accumulation. Transcriptional activation of p53 target genes resulted in an increased amount of proteins with the exception of p21. While p21 transcripts were efficiently translated in 3T3 cells, we failed to see an increase in p21 protein levels after IR in embryonal stem cells. In embryonic stem cells where (anti-proliferative) p53 activity is not necessary, or even unfavorable, p53 is retained in the cytoplasm and prevented from activating its target genes. However, if its activity is beneficial or required, p53 is allowed to accumulate in the nucleus and activates its target genes, even in embryonic stem cells.

  19. Improving biomass and starch accumulation of bioenergy crop duckweed (Landoltia punctata) by abscisic acid application.

    PubMed

    Liu, Yang; Chen, Xiaoyi; Wang, Xinhui; Fang, Yang; Huang, Mengjun; Guo, Ling; Zhang, Yin; Zhao, Hai

    2018-06-22

    Duckweed is a valuable feedstock for bioethanol production due to its high biomass and starch accumulation. In our preliminary experiment, we found that abscisic acid (ABA) could simultaneously increase starch and biomass accumulation of duckweed, but the mechanisms are still unclear. The results showed that the biomass production of duckweed reached up to 59.70 and 63.93 g m -2 in 6 days, respectively, with an increase of 7% (P < 0.05) compared to the control. The starch percentage increased from 2.29% up to 46.18% after 14 days of treatment, with a total of starch level 2.6-fold higher than that of the control. Moreover, the level of endogenous ABA, zeatin-riboside (ZR) and indole-3-acetic acid (IAA) increased, while gibberellins (GAs) decreased. Notably, ABA content in treated samples reached 336.5 mg/kg (fresh weight), which was 7.5-fold greater than that of the control. Importantly, the enzyme activities involved in starch biosynthesis increased while those catalyzing starch degradation decreased after ABA application. Taken together, these results indicated that ABA can promote biomass and starch accumulation by regulating endogenous hormone levels and the activity of starch metabolism related key enzymes. These results will provide an operable method for high starch accumulation in duckweed for biofuels production.

  20. Internal curvature signal and noise in low- and high-level vision

    PubMed Central

    Grabowecky, Marcia; Kim, Yee Joon; Suzuki, Satoru

    2011-01-01

    How does internal processing contribute to visual pattern perception? By modeling visual search performance, we estimated internal signal and noise relevant to perception of curvature, a basic feature important for encoding of three-dimensional surfaces and objects. We used isolated, sparse, crowded, and face contexts to determine how internal curvature signal and noise depended on image crowding, lateral feature interactions, and level of pattern processing. Observers reported the curvature of a briefly flashed segment, which was presented alone (without lateral interaction) or among multiple straight segments (with lateral interaction). Each segment was presented with no context (engaging low-to-intermediate-level curvature processing), embedded within a face context as the mouth (engaging high-level face processing), or embedded within an inverted-scrambled-face context as a control for crowding. Using a simple, biologically plausible model of curvature perception, we estimated internal curvature signal and noise as the mean and standard deviation, respectively, of the Gaussian-distributed population activity of local curvature-tuned channels that best simulated behavioral curvature responses. Internal noise was increased by crowding but not by face context (irrespective of lateral interactions), suggesting prevention of noise accumulation in high-level pattern processing. In contrast, internal curvature signal was unaffected by crowding but modulated by lateral interactions. Lateral interactions (with straight segments) increased curvature signal when no contextual elements were added, but equivalent interactions reduced curvature signal when each segment was presented within a face. These opposing effects of lateral interactions are consistent with the phenomena of local-feature contrast in low-level processing and global-feature averaging in high-level processing. PMID:21209356

  1. A DNA replicon system for rapid high-level production of virus-like particles in plants.

    PubMed

    Huang, Zhong; Chen, Qiang; Hjelm, Brooke; Arntzen, Charles; Mason, Hugh

    2009-07-01

    Recombinant virus-like particles (VLPs) represent a safe and effective vaccine strategy. We previously described a stable transgenic plant system for inexpensive production and oral delivery of VLP vaccines. However, the relatively low-level antigen accumulation and long-time frame to produce transgenic plants are the two major roadblocks in the practical development of plant-based VLP production. In this article, we describe the optimization of geminivirus-derived DNA replicon vectors for rapid, high-yield plant-based production of VLPs. Co-delivery of bean yellow dwarf virus (BeYDV)-derived vector and Rep/RepA-supplying vector by agroinfiltration of Nicotiana benthamiana leaves resulted in efficient replicon amplification and robust protein production within 5 days. Co-expression of the P19 protein of tomato bush stunt virus, a gene silencing inhibitor, further enhanced VLP accumulation by stabilizing the mRNA. With this system, hepatitis B core antigen (HBc) and Norwalk virus capsid protein (NVCP) were produced at 0.80 and 0.34 mg/g leaf fresh weight, respectively. Sedimentation analysis and electron microscopy of transiently expressed antigens verified the efficient assembly of VLPs. Furthermore, a single replicon vector containing a built-in Rep/RepA cassette without P19 drove protein expression at similar levels as the three-component system. These results demonstrate the advantages of fast and high-level production of VLP-based vaccines using the BeYDV-derived DNA replicon system for transient expression in plants. (c) 2009 Wiley Periodicals, Inc.

  2. A DNA replicon system for rapid high-level production of virus-like particles in plants

    PubMed Central

    Huang, Zhong; Chen, Qiang; Hjelm, Brooke; Arntzen, Charles

    2009-01-01

    Recombinant virus-like particles (VLPs) represent a safe and effective vaccine strategy. We previously described a stable transgenic plant system for inexpensive production and oral delivery of VLP vaccines. However, the relatively low level antigen accumulation and long time frame to produce transgenic plants are the two major roadblocks in the practical development of plant-based VLP production. In this paper, we describe the optimization of geminivirus-derived DNA replicon vectors for rapid, high-yield plant-based production of VLPs. Co-delivery of bean yellow dwarf virus (BeYDV)-derived vector and Rep/RepA-supplying vector by agroinfiltration of Nicotiana benthamiana leaves resulted in efficient replicon amplification and robust protein production within five days. Co-expression of the P19 protein of tomato bush stunt virus, a gene silencing inhibitor, further enhanced VLP accumulation by stabilizing the mRNA. With this system, hepatitis B core antigen (HBc) and Norwalk virus capsid protein (NVCP) were produced at 0.80 and 0.34 mg/g leaf fresh weight, respectively. Sedimentation analysis and electron microscopy of transiently expressed antigens verified the efficient assembly of VLPs. Furthermore, a single replicon vector containing a built-in Rep/RepA cassette without p19 drove protein expression at similar levels as the three-component system. These results demonstrate the advantages of fast and high-level production of VLP-based vaccines using the BeYDV-derived DNA replicon system for transient expression in plants. PMID:19309755

  3. Tangeretin inhibits high glucose-induced extracellular matrix accumulation in human glomerular mesangial cells.

    PubMed

    Chen, Fang; Ma, Yali; Sun, Zhiqiang; Zhu, Xiaoguang

    2018-06-01

    Tangeretin (5, 6, 7, 8, 4'-pentamethoxyflavone), a natural compound extracted from citrus plants, has been shown to possess a variety of pharmacological activities, including anti-oxidant, anti-tumor, cytostatic and anti-diabetic properties. However, the role of tangeretin in diabetic nephropathy (DN) has not yet been investigated. This study was undertaken to elucidate the effects of tangeretin on high glucose (HG)-induced oxidative stress and extracellular matrix (ECM) accumulation in human glomerular mesangial cells (MCs) and explore the underlying mechanisms. Our results showed that tangeretin significantly inhibited HG-induced the proliferation of MCs. In addition, tangeretin dramatically reduced the levels of reactive oxygen species (ROS) and malondialdhyde (MDA), and induced SOD activity, as well as inhibited the expression of fibronectin (FN) and collagen IV in HG-stimulated MCs. Furthermore, tangeretin efficiently prevented the activation of ERK signaling pathway in HG-stimulated MCs. Taken together, these data indicated that tangeretin inhibits HG-induced cell proliferation, oxidative stress and ECM expression in glomerular MCs, at least in part, through the inactivation of ERK signaling pathway. Therefore, tangeretin may be a potential agent in the treatment of DN. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  4. Temporal and spatial variations on accumulation of nomilin and limonin in the pummelos.

    PubMed

    Wang, Fusheng; Yu, Xiaohan; Liu, Xiaona; Shen, Wanxia; Zhu, Shiping; Zhao, Xiaochun

    2016-09-01

    Limonoids are the important secondary metabolites in the citrus. In this study, the accumulation of limonoids at different fruit developmental stages and distribution among different genotypes, tissues and developmental stages were investigated in 12 pummelo varieties. The large variations on limonoids concentration were found among different varieties, which ranged from 233.78 mg/kg FW to 4090.41 mg/kg FW in the seeds at full color stage of the fruit. Classification of pummelos based on the limonoids content divided 12 varieties into three groups. It was matched well with the geographic origination of the pummelo varieties, suggesting that the accumulation of limonoids was mainly determined by the genotype of the pummelo. Accumulation of the limonoids in different tissues was highly variable, and in a tissue specific fashion. The trend of the change on the levels of nomilin and limonin in the seeds and segment membrane were corresponded to the physiological development of the fruit. The rapid accumulation of nomilin and limonoids was observed from the physiological ripening of the seeds. It suggested that physiological maturation of the seeds is a key point that the seeds accelerate the accumulation of nomilin and limonin. In most of pummelo varieties, 10% color break of the fruit was a phenotypic landmark associated with the maximum level of nomilin accumulated in the seeds. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. ROAD MAP FOR DEVELOPMENT OF CRYSTAL-TOLERANT HIGH LEVEL WASTE GLASSES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fox, K.; Peeler, D.; Herman, C.

    The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. This road map guides the research and development for formulation and processing of crystaltolerant glasses, identifying near- and long-term activities that need to be completed over the period from 2014 to 2019. The primary objectivemore » is to maximize waste loading for Hanford waste glasses without jeopardizing melter operation by crystal accumulation in the melter or melter discharge riser. The potential applicability to the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF) will also be addressed in this road map. The planned research described in this road map is motivated by the potential for substantial economic benefits (significant reductions in glass volumes) that will be realized if the current constraints (T1% for WTP and TL for DWPF) are approached in an appropriate and technically defensible manner for defense waste and current melter designs. The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal-tolerant high-level waste (HLW) glasses targeting high waste loadings while still meeting process related limits and melter lifetime expectancies. The modeling effort will be an iterative process, where model form and a broader range of conditions, e

  6. High flavonoid accompanied with high starch accumulation triggered by nutrient starvation in bioenergy crop duckweed (Landoltia punctata).

    PubMed

    Tao, Xiang; Fang, Yang; Huang, Meng-Jun; Xiao, Yao; Liu, Yang; Ma, Xin-Rong; Zhao, Hai

    2017-02-15

    As the fastest growing plant, duckweed can thrive on anthropogenic wastewater. The purple-backed duckweed, Landoltia punctata, is rich in starch and flavonoids. However, the molecular biological basis of high flavonoid and low lignin content remains largely unknown, as does the best method to combine nutrients removed from sewage and the utilization value improvement of duckweed biomass. A combined omics study was performed to investigate the biosynthesis of flavonoid and the metabolic flux changes in L. punctata grown in different culture medium. Phenylalanine metabolism related transcripts were identified and carefully analyzed. Expression quantification results showed that most of the flavonoid biosynthetic transcripts were relatively highly expressed, while most lignin-related transcripts were poorly expressed or failed to be detected by iTRAQ based proteomic analyses. This explains why duckweed has a much lower lignin percentage and higher flavonoid content than most other plants. Growing in distilled water, expression of most flavonoid-related transcripts were increased, while most were decreased in uniconazole treated L. punctata (1/6 × Hoagland + 800 mg•L -1 uniconazole). When L. punctata was cultivated in full nutrient medium (1/6 × Hoagland), more than half of these transcripts were increased, however others were suppressed. Metabolome results showed that a total of 20 flavonoid compounds were separated by HPLC in L. punctata grown in uniconazole and full nutrient medium. The quantities of all 20 compounds were decreased by uniconazole, while 11 were increased and 6 decreased when grown in full nutrient medium. Nutrient starvation resulted in an obvious purple accumulation on the underside of each frond. The high flavonoid and low lignin content of L. punctata appears to be predominantly caused by the flavonoid-directed metabolic flux. Nutrient starvation is the best option to obtain high starch and flavonoid accumulation simultaneously

  7. Asynchronous accumulation of lettuce infectious yellows virus RNAs 1 and 2 and identification of an RNA 1 trans enhancer of RNA 2 accumulation.

    PubMed

    Yeh, H H; Tian, T; Rubio, L; Crawford, B; Falk, B W

    2000-07-01

    Time course and mutational analyses were used to examine the accumulation in protoplasts of progeny RNAs of the bipartite Crinivirus, Lettuce infectious yellow virus (LIYV; family Closteroviridae). Hybridization analyses showed that simultaneous inoculation of LIYV RNAs 1 and 2 resulted in asynchronous accumulation of progeny LIYV RNAs. LIYV RNA 1 progeny genomic and subgenomic RNAs could be detected in protoplasts as early as 12 h postinoculation (p.i.) and accumulated to high levels by 24 h p.i. The LIYV RNA 1 open reading frame 2 (ORF 2) subgenomic RNA was the most abundant of all LIYV RNAs detected. In contrast, RNA 2 progeny were not readily detected until ca. 36 h p.i. Mutational analyses showed that in-frame stop codons introduced into five of seven RNA 2 ORFs did not affect accumulation of progeny LIYV RNA 1 or RNA 2, confirming that RNA 2 does not encode proteins necessary for LIYV RNA replication. Mutational analyses also supported that LIYV RNA 1 encodes proteins necessary for replication of LIYV RNAs 1 and 2. A mutation introduced into the LIYV RNA 1 region encoding the overlapping ORF 1B and ORF 2 was lethal. However, mutations introduced into only LIYV RNA 1 ORF 2 resulted in accumulation of progeny RNA 1 near or equal to wild-type RNA 1. In contrast, the RNA 1 ORF 2 mutants did not efficiently support the trans accumulation of LIYV RNA 2. Three distinct RNA 1 ORF 2 mutants were analyzed and all exhibited a similar phenotype for progeny LIYV RNA accumulation. These data suggest that the LIYV RNA 1 ORF 2 encodes a trans enhancer for RNA 2 accumulation.

  8. Asynchronous Accumulation of Lettuce Infectious Yellows Virus RNAs 1 and 2 and Identification of an RNA 1 trans Enhancer of RNA 2 Accumulation

    PubMed Central

    Yeh, Hsin-Hung; Tian, Tongyan; Rubio, Luis; Crawford, Brett; Falk, Bryce W.

    2000-01-01

    Time course and mutational analyses were used to examine the accumulation in protoplasts of progeny RNAs of the bipartite Crinivirus, Lettuce infectious yellow virus (LIYV; family Closteroviridae). Hybridization analyses showed that simultaneous inoculation of LIYV RNAs 1 and 2 resulted in asynchronous accumulation of progeny LIYV RNAs. LIYV RNA 1 progeny genomic and subgenomic RNAs could be detected in protoplasts as early as 12 h postinoculation (p.i.) and accumulated to high levels by 24 h p.i. The LIYV RNA 1 open reading frame 2 (ORF 2) subgenomic RNA was the most abundant of all LIYV RNAs detected. In contrast, RNA 2 progeny were not readily detected until ca. 36 h p.i. Mutational analyses showed that in-frame stop codons introduced into five of seven RNA 2 ORFs did not affect accumulation of progeny LIYV RNA 1 or RNA 2, confirming that RNA 2 does not encode proteins necessary for LIYV RNA replication. Mutational analyses also supported that LIYV RNA 1 encodes proteins necessary for replication of LIYV RNAs 1 and 2. A mutation introduced into the LIYV RNA 1 region encoding the overlapping ORF 1B and ORF 2 was lethal. However, mutations introduced into only LIYV RNA 1 ORF 2 resulted in accumulation of progeny RNA 1 near or equal to wild-type RNA 1. In contrast, the RNA 1 ORF 2 mutants did not efficiently support the trans accumulation of LIYV RNA 2. Three distinct RNA 1 ORF 2 mutants were analyzed and all exhibited a similar phenotype for progeny LIYV RNA accumulation. These data suggest that the LIYV RNA 1 ORF 2 encodes a trans enhancer for RNA 2 accumulation. PMID:10846054

  9. Factors determining accumulation of bisphenol A and alkylphenols at a low trophic level as exemplified by mussels Mytilus trossulus.

    PubMed

    Staniszewska, Marta; Graca, Bożena; Sokołowski, Adam; Nehring, Iga; Wasik, Andrzej; Jendzul, Anna

    2017-01-01

    The aim of the study was to investigate abiotic and biotic factors influencing the accumulation of endocrine disrupting compounds (EDCs) such as bisphenol A (BPA), 4-tert-octylphenol (OP) and 4-nonylphenol (NP) in mussels Mytilus trossulus from the Gulf of Gdansk (Southern Baltic). The key abiotic factor influencing BPA, OP and NP accumulation in mussels is their hydrophilicity/lipophilicity, which affects their main assimilation routes - by digestive tract for the more lipophilic OP and NP, and additionally by the gills for the less lipophilic BPA. As a result, high condition index (i.e. higher soft tissue weight) is more often correlated with high concentrations of OP and NP in mussels than with BPA. Furthermore, alkylphenols have 6-8 times greater accumulative potential than BPA. Concentration of the studied compounds was lower in females than in males following spawning, and the effect lasted longer for BPA than for alkylphenols. The influence of season and hydrological conditions on BPA, OP, NP in the mussel was more pronounced than the proximity of external sources of these compounds. An increase in water temperature in summer probably stimulated the solubility of BPA, the least lipophilic of the studied compounds, and led to increased assimilation of this compound from water (through gills). On the other hand, high OP and NP concentrations in mussels occurred in spring, which was caused by increased surface run-off and sediments resuspension. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Helium accumulation and bubble formation in FeCoNiCr alloy under high fluence He+ implantation

    NASA Astrophysics Data System (ADS)

    Chen, Da; Tong, Y.; Li, H.; Wang, J.; Zhao, Y. L.; Hu, Alice; Kai, J. J.

    2018-04-01

    Face-centered cubic (FCC) high-entropy alloys (HEA), as emerging alloys with equal-molar or near equal-molar constituents, show a promising radiation damage resistance under heavy ion bombardment, making them potential for structural material application in next-generation nuclear reactors, but the accumulation of light helium ions, a product of nuclear fission reaction, has not been studied. The present work experimentally studied the helium accumulation and bubble formation at implantation temperatures of 523 K, 573 K and 673 K in a homogenized FCC FeCoNiCr HEA, a HEA showing excellent radiation damage resistance under heavy ion irradiation. The size and population density of helium bubbles in FeCoNiCr samples were quantitatively analyzed through transmission electron microscopy (TEM), and the helium content existing in bubbles were estimated from a high-pressure Equation of State (EOS). We found that the helium diffusion in such condition was dominated by the self-interstitial/He replacement mechanism, and the corresponding activation energy in FeCoNiCr is comparable with the vacancy migration energy in Ni and austenitic stainless steel but only 14.3%, 31.4% and 51.4% of the accumulated helium precipitated into helium bubbles at 523 K, 573 K and 673 K, respectively, smaller than the pure Ni case. Importantly, the small bubble size suggested that FeCoNiCr HEA has a high resistance of helium bubble formation compared with Ni and steels.

  11. Ecological strategies of Al-accumulating and non-accumulating functional groups from the cerrado sensu stricto.

    PubMed

    Souza, Marcelo C de; Bueno, Paula C P; Morellato, Leonor P C; Habermann, Gustavo

    2015-01-01

    The cerrado's flora comprises aluminum-(Al) accumulating and non-accumulating plants, which coexist on acidic and Al-rich soils with low fertility. Despite their existence, the ecological importance or biological strategies of these functional groups have been little explored. We evaluated the leaf flushing patterns of both groups throughout a year; leaf concentrations of N, P, K, Ca, Mg, S, Al, total flavonoids and polyphenols; as well as the specific leaf area (SLA) on young and mature leaves within and between the groups. In Al-accumulating plants, leaf flushed throughout the year, mainly in May and September; for non-accumulating plants, leaf flushing peaked at the dry-wet seasons transition. However, these behaviors could not be associated with strategies for building up concentrations of defense compounds in leaves of any functional groups. Al-accumulating plants showed low leaf nutrient concentrations, while non-accumulating plants accumulated more macronutrients and produced leaves with high SLA since the juvenile leaf phase. This demonstrates that the increase in SLA is slower in Al-accumulating plants that are likely to achieve SLA values comparable to the rest of the plant community only in the wet season, when sunlight capture is important for the growth of new branches.

  12. Chlamydomonas reinhardtii PsbS Protein Is Functional and Accumulates Rapidly and Transiently under High Light.

    PubMed

    Tibiletti, Tania; Auroy, Pascaline; Peltier, Gilles; Caffarri, Stefano

    2016-08-01

    Photosynthetic organisms must respond to excess light in order to avoid photo-oxidative stress. In plants and green algae the fastest response to high light is non-photochemical quenching (NPQ), a process that allows the safe dissipation of the excess energy as heat. This phenomenon is triggered by the low luminal pH generated by photosynthetic electron transport. In vascular plants the main sensor of the low pH is the PsbS protein, while in the green alga Chlamydomonas reinhardtii LhcSR proteins appear to be exclusively responsible for this role. Interestingly, Chlamydomonas also possesses two PsbS genes, but so far the PsbS protein has not been detected and its biological function is unknown. Here, we reinvestigated the kinetics of gene expression and PsbS and LhcSR3 accumulation in Chlamydomonas during high light stress. We found that, unlike LhcSR3, PsbS accumulates very rapidly but only transiently. In order to determine the role of PsbS in NPQ and photoprotection in Chlamydomonas, we generated transplastomic strains expressing the algal or the Arabidopsis psbS gene optimized for plastid expression. Both PsbS proteins showed the ability to increase NPQ in Chlamydomonas wild-type and npq4 (lacking LhcSR3) backgrounds, but no clear photoprotection activity was observed. Quantification of PsbS and LhcSR3 in vivo indicates that PsbS is much less abundant than LhcSR3 during high light stress. Moreover, LhcSR3, unlike PsbS, also accumulates during other stress conditions. The possible role of PsbS in photoprotection is discussed. © 2016 American Society of Plant Biologists. All Rights Reserved.

  13. Resistance to pathogens in terpene down-regulated orange fruits inversely correlates with the accumulation of D-limonene in peel oil glands.

    PubMed

    Rodríguez, Ana; Shimada, Takehiko; Cervera, Magdalena; Redondo, Ana; Alquézar, Berta; Rodrigo, María Jesús; Zacarías, Lorenzo; Palou, Lluís; López, María M; Peña, Leandro

    2015-01-01

    Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores.

  14. Resistance to pathogens in terpene down-regulated orange fruits inversely correlates with the accumulation of D-limonene in peel oil glands

    PubMed Central

    Rodríguez, Ana; Shimada, Takehiko; Cervera, Magdalena; Redondo, Ana; Alquézar, Berta; Rodrigo, María Jesús; Zacarías, Lorenzo; Palou, Lluís; López, María M; Peña, Leandro

    2015-01-01

    Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores. PMID:26023857

  15. Identification and characterization of a fruit-specific, thaumatin-like protein that accumulates at very high levels in conjunction with the onset of sugar accumulation and berry softening in grapes.

    PubMed Central

    Tattersall, D B; van Heeswijck, R; Høj, P B

    1997-01-01

    The protein composition of the grape (Vitis vinifera cv Muscat of Alexandria) berry was examined from flowering to ripeness by gel electrophoresis. A protein with an apparent molecular mass of 24 kD, which was one of the most abundant proteins in extracts of mature berries, was purified and identified by amino acid sequence to be a thaumatin-like protein. Combined cDNA sequence analysis and electrospray mass spectrometry revealed that this protein, VVTL1 (for V. vinifera thaumatin-like protein 1), is synthesized with a transient signal peptide as seen for apoplastic preproteins. Apart from the removal of the targeting signal and the formation of eight disulfide bonds, VVTL1 undergoes no other posttranslational modification. Southern, northern, and western analyses revealed that VVTL1 is found in the berry only and is encoded by a single gene that is expressed in conjunction with the onset of sugar accumulation and softening. The exact role of VVTL1 is unknown, but the timing of its accumulation correlates with the inability of the fungal pathogen powdery mildew (Uncinula necator) to initiate new infections of the berry. Western analysis revealed that the presence of thaumatin-like proteins in ripening fruit might be a widespread phenomenon. PMID:9232867

  16. What influences heavy metals accumulation in arctic lichen Cetrariella delisei in Svalbard?

    NASA Astrophysics Data System (ADS)

    Węgrzyn, Michał; Wietrzyk, Paulina; Lisowska, Maja; Klimek, Beata; Nicia, Paweł

    2016-12-01

    The main aim of this study was to identify variations in heavy metal concentrations in Cetrariella delisei along a transect from a High Arctic glacier forehead to the shoreline as well as determine the main environmental factors influencing the deposition of heavy metals in arctic lichens. The macrolichen Cetrariella delisei appears to be an interesting alternative to those lichen species used in the past (e.g. Flavocetraria nivalis, Cladonia sp.) for heavy metal biomonitoring purposes in the Arctic: it is widely distributed, easy to identify and reluctantly grazed by reindeer. Fieldwork was conducted in the summer of 2012 in the Kaffiøyra Plain, Oskar II Land, NW Spitsbergen. C. delisei and soil samples were collected from 5 localities. Concentrations of Cr, Mn, Ni, Cu, Zn, Pb, and Cd were measured in each sample. A bioaccumulation factor (BAF) was calculated for all the analyzed elements. The BAFs for Cu, Mn, and Ni showed a relatively low accumulation level in lichen thalli. On the other hand, the BAFs for Cr, Pb, and Zn, revealed an increased accumulation level in C. delisei. The Cd content in lichen is almost equal to its level in the soil. The statistical analyses covered three environmental factors: soil pH, substrate type and distance from the shoreline. The data were examined using the Kruskal-Wallis test, canonical correspondence analysis and a permutation test. The results show that distance from the shoreline had the greatest influence on the majority of the heavy metal concentrations in the lichen thalli and the soil. However, the level of Mn accumulated in the soil is determined by its source in the glacier. Moreover, the soil pH had the greatest effect on the Cd accumulated in the soil and the Mn accumulated in the lichen thalli.

  17. Boron accumulation and toxicity in hybrid poplar (Populus nigra × euramericana).

    PubMed

    Rees, Rainer; Robinson, Brett H; Menon, Manoj; Lehmann, Eberhard; Günthardt-Goerg, Madeleine S; Schulin, Rainer

    2011-12-15

    Poplars accumulate high B concentrations and are thus used for the phytomanagement of B contaminated soils. Here, we performed pot experiments in which Populus nigra × euramericana were grown on a substrate with B concentrations ranging from 13 to 280 mg kg(-1) as H(3)BO(3). Salix viminalis, Brassica juncea, and Lupinus albus were grown under some growing conditions for comparison. Poplar growth was unaffected at soil B treatment levels up to 93 mg kg(-1). Growth was progressively reduced at levels of 168 and 280 mg kg(-1). None of the other species survived at these substrate B levels. At leaf B concentrations <900 mg kg(-1) only <10% of the poplar leaf area showed signs of toxicity. Neutron radiography revealed that chlorotic leaf tissues had B concentrations of 1000-2000 mg kg(-1), while necrotic tissues had >2000 mg kg(-1). Average B concentrations of up to 3500 mg kg(-1) were found in leaves, while spots within leaves had concentrations >7000 mg kg(-1), showing that B accumulation in leaf tissue continued even after the onset of necrosis. The B accumulation ability of P. nigra × euramericana is associated with B hypertolerance in the living tissue and storage of B in dead leaf tissue.

  18. Identification of Genes Associated with Chlorophyll Accumulation in Flower Petals

    PubMed Central

    Ohmiya, Akemi; Hirashima, Masumi; Yagi, Masafumi; Tanase, Koji; Yamamizo, Chihiro

    2014-01-01

    Plants have an ability to prevent chlorophyll accumulation, which would mask the bright flower color, in their petals. In contrast, leaves contain substantial amounts of chlorophyll, as it is essential for photosynthesis. The mechanisms of organ-specific chlorophyll accumulation are unknown. To identify factors that determine the chlorophyll content in petals, we compared the expression of genes related to chlorophyll metabolism in different stages of non-green (red and white) petals (very low chlorophyll content), pale-green petals (low chlorophyll content), and leaves (high chlorophyll content) of carnation (Dianthus caryophyllus L.). The expression of many genes encoding chlorophyll biosynthesis enzymes, in particular Mg-chelatase, was lower in non-green petals than in leaves. Non-green petals also showed higher expression of genes involved in chlorophyll degradation, including STAY-GREEN gene and pheophytinase. These data suggest that the absence of chlorophylls in carnation petals may be caused by the low rate of chlorophyll biosynthesis and high rate of degradation. Similar results were obtained by the analysis of Arabidopsis microarray data. In carnation, most genes related to chlorophyll biosynthesis were expressed at similar levels in pale-green petals and leaves, whereas the expression of chlorophyll catabolic genes was higher in pale-green petals than in leaves. Therefore, we hypothesize that the difference in chlorophyll content between non-green and pale-green petals is due to different levels of chlorophyll biosynthesis. Our study provides a basis for future molecular and genetic studies on organ-specific chlorophyll accumulation. PMID:25470367

  19. Muscle-specific deletion of Prkaa1 enhances skeletal muscle lipid accumulation in mice fed a high-fat diet.

    PubMed

    Wu, Weiche; Xu, Ziye; Zhang, Ling; Liu, Jiaqi; Feng, Jie; Wang, Xinxia; Shan, Tizhong; Wang, Yizhen

    2018-05-01

    Excessive intramyocellular triacylglycerols (IMTGs, muscle lipids) are associated with the abnormal energy metabolism and insulin resistance of skeletal muscle. AMP-activated protein kinase (AMPK), a crucial cellular energy sensor, consists of α, β and γ subunits. Researchers have not clearly determined whether Prkaa1 (also known as AMPKα1) affects IMTG accumulation in skeletal muscle. Here, we show an important role of Prkaa1 in skeletal muscle lipid metabolism. Deletion of muscle Prkaa1 leads to the delayed development of skeletal muscles but does not affect glucose tolerance or insulin sensitivity in animals fed a normal diet. Notably, when animals are fed a high-fat diet, the skeletal muscle of muscle-specific Prkaa1 knockout mice accumulates more lipids than the skeletal muscle of wild-type (WT) mice, with concomitant upregulation of adipogenic gene expressions and downregulation of the expression of genes associated with mitochondrial oxidation. Muscle-specific Prkaa1 ablation also results in hyperlipidemia, which may contribute to the increased IMTG levels. Furthermore, Prkaa1 deletion activates skeletal muscle mTOR signalling, which has a central role in lipid metabolism and mitochondrial oxidation. Collectively, our study provides new insights into the role of Prkaa1 in skeletal muscle. This knowledge may contribute to the treatment of related metabolic diseases.

  20. Ontogenetic dynamics of mercury accumulation in Northwest Atlantic sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Drevnick, P.E.; Horgan, M.J.; Oris, J.T.; Kynard, B.E.

    2006-01-01

    We examined the ontogenetic dynamics of mercury accumulation in sea lamprey (Petromyzon marinus) from the Connecticut River, USA. Mercury concentrations in eggs (mean 84 ng??g-1 wet weight) were lowest of all life stages and correlated to concentrations in females. There was a higher rate of maternal transfer of mercury to eggs compared with teleosts. Ammocoetes had high mercury concentrations for their trophic level (e.g., mean of age-4 ammocoetes 492 ng??g-1 wet weight). A further investigation of four streams showed that ammocoetes reflected the level of contamination in their nursery streams. Concentrations of mercury decreased during metamorphosis from ammocoete to adult. Mercury concentrations in adults ranged from 83 to 942 ng??g-1 wet weight and, unlike teleosts, showed no relation to sex, length, or weight. We provide evidence from stable isotope analyses that this high variability is due to feeding ecology. There are fundamental differences in mercury accumulation between sea lamprey and teleosts. ?? 2006 NRC Canada.

  1. Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xue, Saisi; Uppugundla, Nirmal; Bowman, Michael J.

    Accumulation of recalcitrant oligosaccharides during high-solids loading enzymatic hydrolysis of cellulosic biomass reduces biofuel yields and increases processing costs for a cellulosic biorefinery. Recalcitrant oligosaccharides in AFEX-pretreated corn stover hydrolysate accumulate to the extent of about 18–25 % of the total soluble sugars in the hydrolysate and 12–18 % of the total polysaccharides in the inlet biomass (untreated), equivalent to a yield loss of about 7–9 kg of monomeric sugars per 100 kg of inlet dry biomass (untreated). These oligosaccharides represent a yield loss and also inhibit commercial hydrolytic enzymes, with both being serious bottlenecks for economical biofuel production frommore » cellulosic biomass. Very little is understood about the nature of these oligomers and why they are recalcitrant to commercial enzymes. This work presents a robust method for separating recalcitrant oligosaccharides from high solid loading hydrolysate in gramme quantities. Composition analysis, recalcitrance study and enzyme inhibition study were performed to understand their chemical nature. Results indicate that, oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, and ammonia fibre expansion: AFEX). The methodology for large-scale separation of recalcitrant oligosaccharides from 25 % solids-loading AFEXcorn stover hydrolysate using charcoal fractionation and size exclusion chromatography is reported for the first time. Oligosaccharides with higher degree of polymerization (DP) were recalcitrant towards commercial enzyme mixtures [Ctec2, Htec2 and Multifect pectinase (MP)] compared to lower DP oligosaccharides. Enzyme inhibition studies using processed substrates (Avicel and xylan) showed that low DP oligosaccharides also inhibit commercial enzymes. Addition of monomeric sugars to oligosaccharides increases the

  2. Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis

    DOE PAGES

    Xue, Saisi; Uppugundla, Nirmal; Bowman, Michael J.; ...

    2015-11-26

    Accumulation of recalcitrant oligosaccharides during high-solids loading enzymatic hydrolysis of cellulosic biomass reduces biofuel yields and increases processing costs for a cellulosic biorefinery. Recalcitrant oligosaccharides in AFEX-pretreated corn stover hydrolysate accumulate to the extent of about 18–25 % of the total soluble sugars in the hydrolysate and 12–18 % of the total polysaccharides in the inlet biomass (untreated), equivalent to a yield loss of about 7–9 kg of monomeric sugars per 100 kg of inlet dry biomass (untreated). These oligosaccharides represent a yield loss and also inhibit commercial hydrolytic enzymes, with both being serious bottlenecks for economical biofuel production frommore » cellulosic biomass. Very little is understood about the nature of these oligomers and why they are recalcitrant to commercial enzymes. This work presents a robust method for separating recalcitrant oligosaccharides from high solid loading hydrolysate in gramme quantities. Composition analysis, recalcitrance study and enzyme inhibition study were performed to understand their chemical nature. Results indicate that, oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, and ammonia fibre expansion: AFEX). The methodology for large-scale separation of recalcitrant oligosaccharides from 25 % solids-loading AFEXcorn stover hydrolysate using charcoal fractionation and size exclusion chromatography is reported for the first time. Oligosaccharides with higher degree of polymerization (DP) were recalcitrant towards commercial enzyme mixtures [Ctec2, Htec2 and Multifect pectinase (MP)] compared to lower DP oligosaccharides. Enzyme inhibition studies using processed substrates (Avicel and xylan) showed that low DP oligosaccharides also inhibit commercial enzymes. Addition of monomeric sugars to oligosaccharides increases the

  3. Assessing the Capacity of Plant Species to Accumulate Particulate Matter in Beijing, China

    PubMed Central

    Mo, Li; Ma, Zeyu; Xu, Yansen; Sun, Fengbin; Lun, Xiaoxiu; Liu, Xuhui; Chen, Jungang; Yu, Xinxiao

    2015-01-01

    Air pollution causes serious problems in spring in northern China; therefore, studying the ability of different plants to accumulate particulate matter (PM) at the beginning of the growing season may benefit urban planners in their attempts to control air pollution. This study evaluated deposits of PM on the leaves and in the wax layer of 35 species (11 shrubs, 24 trees) in Beijing, China. Differences in the accumulation of PM were observed between species. Cephalotaxus sinensis, Euonymus japonicus, Broussonetia papyriferar, Koelreuteria paniculata and Quercus variabilis were all efficient in capturing small particles. The plants exhibiting high amounts of total PM accumulation (on leaf surfaces and/or in the wax layer), also showed comparatively high levels of PM accumulation across all particle sizes. A comparison of shrubs and trees did not reveal obvious differences in their ability to accumulate particles based on growth form; a combination of plantings with different growth forms can efficiently reduce airborne PM concentrations near the ground. To test the relationships between leaf traits and PM accumulation, leaf samples of selected species were observed using a scanning electron microscope. Growth forms with greater amounts of pubescence and increased roughness supported PM accumulation; the adaxial leaf surfaces collected more particles than the abaxial surfaces. The results of this study may inform the selection of species for urban green areas where the goal is to capture air pollutants and mitigate the adverse effects of air pollution on human health. PMID:26506104

  4. Evaluation of zinc accumulation, allocation, and tolerance in Zea mays L. seedlings: implication for zinc phytoextraction.

    PubMed

    Bashmakov, Dmitry I; Lukatkin, Alexander S; Anjum, Naser A; Ahmad, Iqbal; Pereira, Eduarda

    2015-10-01

    This work investigated the accumulation, allocation, and impact of zinc (Zn; 1.0 μM-10 mM) in maize (Zea mays L.) seedlings under simulated laboratory conditions. Z. mays exhibited no significant change in its habitus (the physical characteristics of plants) up to 10-1000 μM of Zn (vs 5-10 mM Zn). Zn tolerance evaluation, based on the root test, indicated a high tolerance of Z. mays to both low and intermediate (or relatively high) concentrations of Zn, whereas this plant failed to tolerate 10 mM Zn and exhibited a 5-fold decrease in its Zn tolerance. Contingent to Zn treatment levels, Zn hampered the growth of axial organs and brought decreases in the leaf area, water regime, and biomass accumulation. Nevertheless, at elevated levels of Zn (10 mM), Zn(2+) was stored in the root cytoplasm and inhibited both axial organ growth and water regime. However, accumulation and allocation of Zn in Z. mays roots, studied herein employing X-ray fluorimeter and histochemical methods, were close to Zn accumulator plants. Overall, the study outcomes revealed Zn tolerance of Z. mays, and also implicate its potential role in Zn phytoextraction.

  5. Zanthoxylum piperitum DC ethanol extract suppresses fat accumulation in adipocytes and high fat diet-induced obese mice by regulating adipogenesis.

    PubMed

    Gwon, So Young; Ahn, Ji Yun; Kim, Tae Wan; Ha, Tae Youl

    2012-01-01

    This study was conducted to determine the anti-obesity effects of Zanthoxylum piperitum DC fruit ethanol extract (ZPE) in 3T3-L1 adipocytes and obese mice fed a high-fat diet. We evaluated the influence of the addition of ZPE to a high-fat diet on body weight, adipose tissue weight, serum and hepatic lipids in C57BL/6 mice. In addition, adipogenic gene expression was determined by Western blot and real-time reverse transcription-PCR analysis. We assessed the effect of ZPE on 3T3-L1 preadipocyte differentiation. ZPE reduced weight gain, white adipose tissue mass, and serum triglyceride and cholesterol levels (p<0.05) in high-fat diet-fed C57BL/6 mice. ZPE decreased lipid accumulation and PPARγ, C/EBPα, SREBP-1, and FAS protein and mRNA levels in the liver. ZPE inhibited in vitro adipocyte differentiation in a dose-dependent manner and significantly attenuated adipogenic transcription factors, such as PPARγ, C/EBPα, and SREBP-1 in 3T3L1 cells. These findings suggest that Z. piperitum DC exerts an anti-obesity effect by inhibiting adipogenesis through the downregulation of genes involved in the adipogenesis pathway.

  6. Effects of Yogurt Containing Fermented Pepper Juice on the Body Fat and Cholesterol Level in High Fat and High Cholesterol Diet Fed Rat.

    PubMed

    Yeon, Su-Jung; Hong, Go-Eun; Kim, Chang-Kyu; Park, Woo Joon; Kim, Soo-Ki; Lee, Chi-Ho

    2015-01-01

    This experiment investigated whether yogurt containing fermented pepper juice (FPJY) affects cholesterol level in high fat and high cholesterol diet (HFCD) fed rat. Twenty five Sprague-Dawley male rats of 7 wk were divided into 5 groups, and fed following diets for 9 wk; CON (control diet), HFCD (HFCD), PY (HFCD supplemented with 2% of plain yogurt), LFY (HFCD supplemented with 2% of FPJY), and HFY (HFCD supplemented with 5% of FPJY). In the LFY group, hepatic total lipid level decreased significantly compared to the HFCD group (p<0.05). Serum HDL cholesterol level tended to increase and hepatic total cholesterol level decreased and were comparable to the CON group (p>0.05). In HFY group, body weight and hepatic total lipid level significantly decreased over the HFCD group (p<0.05). Serum and hepatic total cholesterol level, kidney, and body fat weights decreased, and were compared to the CON group (p>0.05). Liver weight decreased as FPJY content was increased. Results suggested FPJY would inhibit organ hypertrophy and accumulation of body fat, hepatic lipid, and cholesterol in HFCD fed rat.

  7. Trehalose accumulation induced during the oxidative stress response is independent of TPS1 mRNA levels in Candida albicans.

    PubMed

    Zaragoza, Oscar; González-Párraga, Pilar; Pedreño, Yolanda; Alvarez-Peral, Francisco J; Argüelles, Juan-Carlos

    2003-06-01

    Growing cells of the Candida albicans trehalose-deficient mutant tps1/tps1 were extremely sensitive to severe oxidative stress exposure (H2O2). However, their viability was not affected after saline stress or heat-shock treatments, being roughly equivalent to that of the parental strain. In wild-type cells, these adverse conditions induced the intracellular accumulation of trehalose together with activation of trehalose-6P synthase, whereas the endogenous trehalose content and the corresponding biosynthetic activity were barely detectable in the tps1/tps1 mutant. The addition of cycloheximide did not prevent the marked induction of trehalose-6P synthase activity. Furthermore, the presence of H2O2 decreased the level of TPS1 mRNA expression. Hence, the conspicuous trehalose accumulation in response to oxidative stress is not induced by increased transcription of TPS1. Our results are consistent with a specific requirement of trehalose in order to withstand a severe oxidative stress in C. albicans, and suggest that trehalose accumulation observed under these conditions is a complex process that most probably involves post-translational modifications of the trehalose synthase complex.

  8. Using SO2 camera imagery and seismicity to examine degassing and gas accumulation at Kīlauea Volcano, May 2010

    USGS Publications Warehouse

    Nadeau, Patricia A; Werner, Cynthia A.; Waite, Gregory P.; Carn, Simon A; Brewer, Ian D; Elias, Tamar; Sutton, Andrew; Kern, Christoph

    2015-01-01

    SO2 camera measurements at Kīlauea Volcano, Hawaii, in May of 2010 captured two occurrences of lava lake rise and fall within the Halema'um'au Crater summit vent. During high lava stands we observed diminished SO2 emission rates and decreased seismic tremor. Similar events at Kīlauea have been described as the result of sporadic degassing following gas accumulation beneath a mostly impermeable lava lake surface. Incorporation of SO2 camera data into a multi-parameter dataset gives credence to the likelihood of shallow gas accumulation as the cause of these high stand events, with accumulated gas release upon lake-level drop compensating for the gas deficit reached during accumulation.

  9. Sonoporation enhances liposome accumulation and penetration in tumors with low EPR.

    PubMed

    Theek, Benjamin; Baues, Maike; Ojha, Tarun; Möckel, Diana; Veettil, Seena Koyadan; Steitz, Julia; van Bloois, Louis; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2016-06-10

    The Enhanced Permeability and Retention (EPR) effect is a highly variable phenomenon. To enhance EPR-mediated passive drug targeting to tumors, several different pharmacological and physical strategies have been evaluated over the years, including e.g. TNFα-treatment, vascular normalization, hyperthermia and radiotherapy. Here, we systematically investigated the impact of sonoporation, i.e. the combination of ultrasound (US) and microbubbles (MB), on the tumor accumulation and penetration of liposomes. Two different MB formulations were employed, and their ability to enhance liposome accumulation and penetration was evaluated in two different tumor models, which are both characterized by relatively low levels of EPR (i.e. highly cellular A431 epidermoid xenografts and highly stromal BxPC-3 pancreatic carcinoma xenografts). The liposomes were labeled with two different fluorophores, enabling in vivo computed tomography/fluorescence molecular tomography (CT-FMT) and ex vivo two-photon laser scanning microscopy (TPLSM). In both models, in spite of relatively high inter- and intra-individual variability, a trend towards improved liposome accumulation and penetration was observed. In treated tumors, liposome concentrations were up to twice as high as in untreated tumors, and sonoporation enhanced the ability of liposomes to extravasate out of the blood vessels into the tumor interstitium. These findings indicate that sonoporation may be a useful strategy for improving drug targeting to tumors with low EPR. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Consumption of a high-fat diet, but not regular endurance exercise training, regulates hypothalamic lipid accumulation in mice

    PubMed Central

    Borg, Melissa L; Omran, Simin Fallah; Weir, Jacquelyn; Meikle, Peter J; Watt, Matthew J

    2012-01-01

    Obesity is characterised by increased storage of fatty acids in an expanded adipose tissue mass and in peripheral tissues such as the skeletal muscle and liver, where it is associated with the development of insulin resistance. Insulin resistance also develops in the central nervous system with high-fat feeding. The capacity for hypothalamic cells to accumulate/store lipids, and the effects of obesity remain undefined. The aims of this study were (1) to examine hypothalamic lipid content in mice with increased dietary fat intake and in obese ob/ob mice fed a low-fat diet, and (2) to determine whether endurance exercise training could reduce hypothalamic lipid accumulation in high-fat fed mice. Male C57BL/6 mice were fed a low- (LFD) or high-fat diet (HFD) for 12 weeks; ob/ob mice were maintained on a chow diet. HFD-exercise (HFD-ex) mice underwent 12 weeks of high-fat feeding with 6 weeks of treadmill exercise training (increasing from 30 to 70 min day−1). Hypothalamic lipids were assessed by unbiased mass spectrometry. The HFD increased body mass and hepatic lipid accumulation, and induced glucose intolerance, while the HFD-ex mice had reduced body weight and improved glucose tolerance. A total of 335 lipid molecular species were identified and quantified. Lipids known to induce insulin resistance, including ceramide (22%↑), diacylglycerol (25%↑), lysophosphatidylcholine (17%↑), cholesterol esters (60%↑) and dihexosylceramide (33%↑), were increased in the hypothalamus of HFD vs. LFD mice. Hypothalamic lipids were unaltered with exercise training and in the ob/ob mice, suggesting that obesity per se does not alter hypothalamic lipids. Overall, hypothalamic lipid accumulation is regulated by dietary lipid content and is refractory to change with endurance exercise training. PMID:22674717

  11. Consumption of a high-fat diet, but not regular endurance exercise training, regulates hypothalamic lipid accumulation in mice.

    PubMed

    Borg, Melissa L; Omran, Simin Fallah; Weir, Jacquelyn; Meikle, Peter J; Watt, Matthew J

    2012-09-01

    Obesity is characterised by increased storage of fatty acids in an expanded adipose tissue mass and in peripheral tissues such as the skeletal muscle and liver, where it is associated with the development of insulin resistance. Insulin resistance also develops in the central nervous system with high-fat feeding. The capacity for hypothalamic cells to accumulate/store lipids, and the effects of obesity remain undefined. The aims of this study were (1) to examine hypothalamic lipid content in mice with increased dietary fat intake and in obese ob/ob mice fed a low-fat diet, and (2) to determine whether endurance exercise training could reduce hypothalamic lipid accumulation in high-fat fed mice. Male C57BL/6 mice were fed a low- (LFD) or high-fat diet (HFD) for 12 weeks; ob/ob mice were maintained on a chow diet. HFD-exercise (HFD-ex) mice underwent 12 weeks of high-fat feeding with 6 weeks of treadmill exercise training (increasing from 30 to 70 min day(-1)). Hypothalamic lipids were assessed by unbiased mass spectrometry. The HFD increased body mass and hepatic lipid accumulation, and induced glucose intolerance, while the HFD-ex mice had reduced body weight and improved glucose tolerance. A total of 335 lipid molecular species were identified and quantified. Lipids known to induce insulin resistance, including ceramide (22%↑), diacylglycerol (25%↑), lysophosphatidylcholine (17%↑), cholesterol esters (60%↑) and dihexosylceramide (33%↑), were increased in the hypothalamus of HFD vs. LFD mice. Hypothalamic lipids were unaltered with exercise training and in the ob/ob mice, suggesting that obesity per se does not alter hypothalamic lipids. Overall, hypothalamic lipid accumulation is regulated by dietary lipid content and is refractory to change with endurance exercise training.

  12. Dual Mode NOx Sensor: Measuring Both the Accumulated Amount and Instantaneous Level at Low Concentrations

    PubMed Central

    Groß, Andrea; Beulertz, Gregor; Marr, Isabella; Kubinski, David J.; Visser, Jaco H.; Moos, Ralf

    2012-01-01

    The accumulating-type (or integrating-type) NOx sensor principle offers two operation modes to measure low levels of NOx: The direct signal gives the total amount dosed over a time interval and its derivative the instantaneous concentration. With a linear sensor response, no baseline drift, and both response times and recovery times in the range of the gas exchange time of the test bench (5 to 7 s), the integrating sensor is well suited to reliably detect low levels of NOx. Experimental results are presented demonstrating the sensor’s integrating properties for the total amount detection and its sensitivity to both NO and to NO2. We also show the correlation between the derivative of the sensor signal and the known gas concentration. The long-term detection of NOx in the sub-ppm range (e.g., for air quality measurements) is discussed. Additionally, a self-adaption of the measurement range taking advantage of the temperature dependency of the sensitivity is addressed. PMID:22736980

  13. SET oncoprotein accumulation regulates transcription through DNA demethylation and histone hypoacetylation.

    PubMed

    Almeida, Luciana O; Neto, Marinaldo P C; Sousa, Lucas O; Tannous, Maryna A; Curti, Carlos; Leopoldino, Andreia M

    2017-04-18

    Epigenetic modifications are essential in the control of normal cellular processes and cancer development. DNA methylation and histone acetylation are major epigenetic modifications involved in gene transcription and abnormal events driving the oncogenic process. SET protein accumulates in many cancer types, including head and neck squamous cell carcinoma (HNSCC); SET is a member of the INHAT complex that inhibits gene transcription associating with histones and preventing their acetylation. We explored how SET protein accumulation impacts on the regulation of gene expression, focusing on DNA methylation and histone acetylation. DNA methylation profile of 24 tumour suppressors evidenced that SET accumulation decreased DNA methylation in association with loss of 5-methylcytidine, formation of 5-hydroxymethylcytosine and increased TET1 levels, indicating an active DNA demethylation mechanism. However, the expression of some suppressor genes was lowered in cells with high SET levels, suggesting that loss of methylation is not the main mechanism modulating gene expression. SET accumulation also downregulated the expression of 32 genes of a panel of 84 transcription factors, and SET directly interacted with chromatin at the promoter of the downregulated genes, decreasing histone acetylation. Gene expression analysis after cell treatment with 5-aza-2'-deoxycytidine (5-AZA) and Trichostatin A (TSA) revealed that histone acetylation reversed transcription repression promoted by SET. These results suggest a new function for SET in the regulation of chromatin dynamics. In addition, TSA diminished both SET protein levels and SET capability to bind to gene promoter, suggesting that administration of epigenetic modifier agents could be efficient to reverse SET phenotype in cancer.

  14. Effects of dietary lysine levels and lighting conditions on intramuscular fat accumulation in growing pigs.

    PubMed

    Katsumata, Masaya; Kobayashi, Hiroyuki; Ashihara, Akane; Ishida, Aiko

    2018-04-29

    This study was conducted to test our hypothesis that intramuscular fat (IMF) accumulation increases in pigs fed on a low lysine diet during the dark period than those fed on the same diet during the light period. Using barrows aged 6 weeks, we monitored whether serum glucose and insulin levels were affected by light conditions. Two diets with different levels of lysine, 0.78% (LL diet) and 1.37% (control diet) were prepared. Eight pigs were fed on the diet during the light period, while the remaining pigs were fed during the dark period. The pigs were fed either the LL diet or the control diet. Although IMF contents of Longissimus dorsi (LD) muscle were higher in the pigs fed on a LL diet (p < .05), the light conditions had no effect. Low dietary lysine caused reduction in serum glucose levels (p < .05) and serum insulin levels (p = .0613). However, they were also unaffected by the lighting conditions. To gain further insights, we determined the messenger RNA levels of insulin receptor, insulin receptor substrate 1, acetyl CoA carboxylase, and fatty acid synthase in LD and Rhomboideus muscles and in the liver. © 2018 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.

  15. Receptor mediated elevation in FABP4 levels by advanced glycation end products induces cholesterol and triacylglycerol accumulation in THP-1 macrophages.

    PubMed

    Wang, Xiao Qun; Yang, Ke; He, Yu Song; Lu, Lin; Shen, Wei Feng

    2011-06-01

    Excessive formation of advanced glycation end products (AGE) and lipid accumulation in macrophages play a pivotal role in the progression of atherosclerosis in diabetes mellitus. This study aimed to determine the molecular link between AGE-induced fatty acid binding protein 4 (FABP4) expression and macrophage lipid accumulation. AGE-BSA markedly increased macrophage FABP4 expression via engagement of RAGE, a 35-kDa transmembrane receptor that is able to bind extracellular AGE and responsible for the corresponding signal transduction, whereas knockdown of RAGE significantly reversed the FABP4 up-regulation. This effect was further paralleled with elevated intracellular total cholesterol and triacylglycerol levels. Finally, administration of FABP4 inhibitor totally abolished the increased lipid contents in response to AGE-BSA. These results indicate that FABP4 up-regulation is responsible for the enhanced macrophage lipid accumulation by AGE, which may underlie the accelerated formation of foam cells and development of atherosclerotic cardiovascular diseases in diabetic patients.

  16. Ferritin accumulation under iron scarcity in Drosophila iron cells.

    PubMed

    Mehta, A; Deshpande, A; Bettedi, L; Missirlis, F

    2009-10-01

    Ferritins are highly stable, multi-subunit protein complexes with iron-binding capacities that reach 4500 iron atoms per ferritin molecule. The strict dependence of cellular physiology on an adequate supply of iron cofactors has likely been a key driving force in the evolution of ferritins as iron storage molecules. The insect intestine has long been known to contain cells that are responsive to dietary iron levels and a specialized group of "iron cells" that always accumulate iron-loaded ferritin, even when no supplementary iron is added to the diet. Here, we further characterize ferritin localization in Drosophila melanogaster larvae raised under iron-enriched and iron-depleted conditions. High dietary iron intake results in ferritin accumulation in the anterior midgut, but also in garland (wreath) cells and in pericardial cells, which together filter the circulating hemolymph. Ferritin is also abundant in the brain, where levels remain unaltered following dietary iron chelation, a treatment that depletes ferritin from the aforementioned tissues. We attribute the stability of ferritin levels in the brain to the function of the blood-brain barrier that may shield this organ from systemic iron fluctuations. Most intriguingly, our dietary manipulations demonstrably iron-depleted the iron cells without a concomitant reduction in their production of ferritin. Therefore, insect iron cells may constitute an exception from the evolutionary norm with respect to iron-dependent ferritin regulation. It will be of interest to decipher both the physiological purpose served and the mechanism employed to untie ferritin regulation from cellular iron levels in this cell type.

  17. High-potential accumulation and tolerance in the submerged hydrophyte Hydrilla verticillata (L.f.) Royle for nickel-contaminated water.

    PubMed

    Song, Yang; Zhang, Ling-Lei; Li, Jia; He, Xiao-Jia; Chen, Min; Deng, Yun

    2018-06-18

    Water contamination by nickel (Ni) has become an increasing concern in recent decades. Hydrilla verticillata (L.f.) Royle has been recognized as a promising accumulator of several potentially toxic elements (PTEs) in phytoremediation, but its Ni-accumulation characteristics and its mechanisms of tolerance to Ni remain largely unknown. This research investigated the biochemical responses of leaves and stems of H. verticillata to various concentrations of Ni (5, 10, 15, 20, and 40 μM) over periods of 7, 14, or 21 days. Plants accumulated considerable Ni to a maximum amount of 1080 mg kg -1 dry weight (DW) with a maximum bioconcentration factor of 1100; thus, high Ni accumulation was detected in H. verticillata. Low concentrations (5-15 μM) or short durations (less than 14 days) of Ni exposure might promote plant growth without adversely affecting normal metabolism. After peaking at day 14, a decline in bioaccumulation was unexpectedly observed as a long-term effect of Ni toxicity. Malondialdehyde content and the activities of defense-related enzymes changed in a similar pattern after treatment with Ni, increasing with both Ni concentration and exposure time to a peak (often at 5-15 μM on day 14), followed by a decline. Through a comprehensive analysis of all the test parameters, the tolerance thresholds were determined to be > 40.0 μM, 24.0 μM, and 15.8 μM at days 7, 14, and 21, respectively. Hydrilla verticillata could be a "high-potential accumulator" capable of decontaminating aquatic bodies polluted by Ni within the threshold range. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Hyperspectral Stimulated Raman Scattering Microscopy Unravels Aberrant Accumulation of Saturated Fat in Human Liver Cancer.

    PubMed

    Yan, Shuai; Cui, Sishan; Ke, Kun; Zhao, Bixing; Liu, Xiaolong; Yue, Shuhua; Wang, Ping

    2018-06-05

    Lipid metabolism is dysregulated in human cancers. The analytical tools that could identify and quantitatively map metabolites in unprocessed human tissues with submicrometer resolution are highly desired. Here, we implemented analytical hyperspectral stimulated Raman scattering microscopy to map the lipid metabolites in situ in normal and cancerous liver tissues from 24 patients. In contrast to the conventional wisdom that unsaturated lipid accumulation enhances tumor cell survival and proliferation, we unexpectedly visualized substantial amount of saturated fat accumulated in cancerous liver tissues, which was not seen in majority of their adjacent normal tissues. Further analysis by mass spectrometry confirmed significant high levels of glyceryl tripalmitate specifically in cancerous liver. These findings suggest that the aberrantly accumulated saturated fat may have great potential to be a metabolic biomarker for liver cancer.

  19. Patterns of sediment accumulation in the tidal marshes of Maine

    USGS Publications Warehouse

    Wood, M.E.; Kelley, J.T.; Belknap, D.F.

    1989-01-01

    One year's measurements of surficial sedimentation rates (1986-1987) for 26 Maine marsh sites were made over marker horizons of brick dust. Observed sediment accumulation rates, from 0 to 13 mm yr-1, were compared with marsh morphology, local relative sea-level rise rate, mean tidal range, and ice rafting activity. Marshes with four different morphologies (back-barrier, fluvial, bluff-toe, and transitional) showed distinctly different sediment accumulation rates. In general, back-barrier marshes had the highest accumulation rates and blufftoe marshes had the lowest rates, with intermediate values for transitional and fluvial marshes. No causal relationship between modern marsh sediment accumulation rate and relative sea-level rise rate (from tide gauge records) was observed. Marsh accretionary balance (sediment accumulation rate minus relative sea-level rise rate) did not correlate with mean tidal range for this meso- to macro-tidal area. Estimates of ice-rafted debris on marsh sites ranged from 0% to >100% of measured surficial sedimentation rates, indicating that ice transport of sediment may make a significant contribution to surficial sedimentation on Maine salt marshes. ?? 1989 Estuarine Research Federation.

  20. FACTORS ASSOCIATED WITH PENTOSIDINE ACCUMULATION IN THE HUMAN VITREOUS.

    PubMed

    van Deemter, Marielle; Bank, Ruud A; Vehof, Jelle; Hooymans, Johanna M M; Los, Leonoor I

    2017-04-01

    To explore factors associated with pentosidine accumulation in the human vitreous. Vitreous samples were obtained during trans pars plana vitrectomy for macular hole or rhegmatogenous retinal detachment. Patient characteristics included age, gender, and diabetes mellitus. Ocular characteristics included pseudophakia, posterior vitreous detachment, and presence of intraocular fibrosis (epiretinal membrane, proliferative vitreoretinopathy, or both). Pentosidine concentration as a measure of accumulation of advanced glycation end products was determined by high performance liquid chromatography. Pentosidine concentrations were measured in 222 vitrectomy samples (118 female and 104 male patients [median age 66 years], treated for macular hole [n = 105] or rhegmatogenous retinal detachment [n = 117]). Pentosidine was found to accumulate significantly with age (P < 0.001). After correction for age, a multivariable linear regression model revealed significantly higher pentosidine values in eyes with intraocular fibrosis (P = 0.001), in phakic as compared with pseudophakic eyes (P = 0.02), and in the absence of a complete posterior vitreous detachment (P = 0.018). The authors found no association with diabetes mellitus or gender. This study confirmed an age-related pentosidine accumulation in the vitreous and found new factors relating to pentosidine levels. Findings support the hypothesis of enzyme-induced vitreous liquefaction and the hypothesis of pentosidine as a pro-fibrotic factor.

  1. Carbon storage and long-term rate of accumulation in high-altitude Andean peatlands of Bolivia

    Treesearch

    J.A. Hribljan; D.J. Cooper; J. Sueltenfuss; E.C. Wolf; K.A. Heckman; Erik Lilleskov; R.A. Chimner

    2015-01-01

    The high-altitude (4,500+ m) Andean mountain range of north-western Bolivia contains many peatlands. Despite heavy grazing pressure and potential damage from climate change, little is known about these peatlands. Our objective was to quantify carbon pools, basal ages and long-term peat accumulation rates in peatlands in two areas of the arid puna ecoregion of Bolivia:...

  2. Cadmium accumulation in the rootless macrophyte Wolffia globosa and its potential for phytoremediation.

    PubMed

    Xie, Wan-Ying; Huang, Qing; Li, Gang; Rensing, Christopher; Zhu, Yong-Guan

    2013-01-01

    Cadmium (Cd) pollution around the world is a serious issue demanding acceptable solutions, one of which is phytoremediation that is both cost-effective and eco-friendly. Removal of Cd from contaminated water using plants with high growth rates and sufficient Cd accumulation abilities could be an appropriate choice. Here, we investigated a potential Cd accumulator, Wolffia, a rootless duckweed with high growth rate. Cd uptake, accumulation, tolerance, and phytofiltration ability by Wolffia globosa were examined. Furthermore, the effects of arsenic (As) on Cd uptake and phytofiltration by W. globosa were also studied. Cd uptake kinetics showed a linear pattern and a hyperbolic pattern without a plateau in lower (0-2 microM) and higher (0-200 microM) Cd concentration ranges, respectively, suggesting rapid Cd uptake by W. globosa Cd accumulation ability by W. globosa was higher at Cd concentrations < 10 microM than at >10 microM. All the five species of Wolffia exposed to I microM Cd for 5 days accumulated > 500 mg Cd kg(-1) DW. Ten gram fresh W. globosa could diminish almost all the Cd (2 microM) in a 200 mL solution. This enormous accumulation ability was mostly due to passive adsorption of Cd by the apoplast. Arsenic had no significant effect on Cd uptake and phytofiltration. The fresh fronds also showed a great As extracting ability. The results indicated that Wolffia is a strong Cd accumulator and has great Cd phytoremediation potential. Therefore, this plant can be used in fresh aquatic environments co-contaminated by low-levels of Cd and As.

  3. Starch and lipid accumulation in eight strains of six Chlorella species under comparatively high light intensity and aeration culture conditions.

    PubMed

    Takeshita, Tsuyoshi; Ota, Shuhei; Yamazaki, Tomokazu; Hirata, Aiko; Zachleder, Vilém; Kawano, Shigeyuki

    2014-04-01

    The microalgae family Chlorella species are known to accumulate starch and lipids. Although nitrogen or phosphorous deficiencies promote starch and lipids formation in many microalgae, these deficiencies also limit their growth and productivity. Therefore, the Chlorellaceae strains were attempted to increase starch and lipids productivity under high-light-intensity conditions (600-μmol photons m(-2)s(-1)). The 12:12-h light-dark (LD) cycle conditions elicited more stable growth than the continuous light (LL) conditions, whereas the starch and lipids yields increased in LL conditions. The amount of starch and lipids per cell increased in Chlorella viscosa and Chlorella vulgaris in sulfur-deficient medium, and long-chain fatty acids with 20 or more carbon atoms accumulated in cells grown in sulfur-deficient medium. Accumulation of starch and lipids was investigated in eight strains. The accumulation was strain-dependent, and varied according to the medium and light conditions. Five of the eight Chlorella strains exhibited similar accumulation patterns. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Spatio-Temporal Variability of Recent Snow Accumulation Across the West Antarctic Ice Sheet Divide Using Ultra-High Frequency Radar and Shallow Firn Cores

    NASA Astrophysics Data System (ADS)

    Keeler, D. G.; Rupper, S.; Forster, R. R.; Miège, C.; Brewer, S.; Koenig, L.

    2017-12-01

    increasing the number of high resolution accumulation records available in these data-sparse regions. An increased understanding of the variability in magnitude and past rates of surface mass balance can provide better constraints on sea level projections and more precise context for present-day and future observations in these regions.

  5. Identification of oleaginous yeast strains able to accumulate high intracellular lipids when cultivated in alkaline pretreated corn stover

    PubMed Central

    Sitepu, Irnayuli R.; Jin, Mingjie; Fernandez, J. Enrique; da Costa Sousa, Leonardo; Balan, Venkatesh; Boundy-Mills, Kyria L.

    2015-01-01

    Microbial oil is a potential alternative to food/plant-derived biodiesel fuel. Our previous screening studies identified a wide range of oleaginous yeast species, using a defined laboratory medium known to stimulate lipid accumulation. In this study, the ability of these yeasts to grow and accumulate lipids was further investigated in synthetic hydrolysate (SynH) and authentic ammonia fiber expansion (AFEX™)-pretreated corn stover hydrolysate (ACSH). Most yeast strains tested were able to accumulate lipids in SynH, but only a few were able to grow and accumulate lipids in ACSH medium. Cryptococcus humicola UCDFST 10-1004 was able to accumulate as high as 15.5 g/L lipids, out of a total of 36 g/L cellular biomass when grown in ACSH, with a cellular lipid content of 40% of cell dry weight. This lipid production is among the highest reported values for oleaginous yeasts grown in authentic hydrolysate. Pre-culturing in SynH media with xylose as sole carbon source enabled yeasts to assimilate both glucose and xylose more efficiently in the subsequent hydrolysate medium. This study demonstrates that ACSH is a suitable medium for certain oleaginous yeasts to convert lignocellullosic sugars to triacylglycerols for production of biodiesel and other valuable oleochemicals. PMID:25052467

  6. High-throughput imaging method for direct assessment of GM1 ganglioside levels in mammalian cells.

    PubMed

    Acosta, Walter; Martin, Reid; Radin, David N; Cramer, Carole L

    2016-03-01

    GM1-gangliosidosis is an inherited autosomal recessive disorder caused by mutations in the gene GLB1, which encodes acid β-galactosidase (β-gal). The lack of activity in this lysosomal enzyme leads to accumulation of GM1 gangliosides (GM1) in cells. We have developed a high-content-imaging method to assess GM1 levels in fibroblasts that can be used to evaluate substrate reduction in treated GLB1(-/-) cells [1]. This assay allows fluorescent quantification in a multi-well system which generates unbiased and statistically significant data. Fluorescently labeled Cholera Toxin B subunit (CTXB), which specifically binds to GM1 gangliosides, was used to detect in situ GM1 levels in a fixed monolayer of fibroblasts. This sensitive, rapid, and inexpensive method facilitates in vitro drug screening in a format that allows a high number of replicates using low working volumes.

  7. Chlamydomonas reinhardtii PsbS Protein Is Functional and Accumulates Rapidly and Transiently under High Light1

    PubMed Central

    Tibiletti, Tania; Auroy, Pascaline; Peltier, Gilles; Caffarri, Stefano

    2016-01-01

    Photosynthetic organisms must respond to excess light in order to avoid photo-oxidative stress. In plants and green algae the fastest response to high light is non-photochemical quenching (NPQ), a process that allows the safe dissipation of the excess energy as heat. This phenomenon is triggered by the low luminal pH generated by photosynthetic electron transport. In vascular plants the main sensor of the low pH is the PsbS protein, while in the green alga Chlamydomonas reinhardtii LhcSR proteins appear to be exclusively responsible for this role. Interestingly, Chlamydomonas also possesses two PsbS genes, but so far the PsbS protein has not been detected and its biological function is unknown. Here, we reinvestigated the kinetics of gene expression and PsbS and LhcSR3 accumulation in Chlamydomonas during high light stress. We found that, unlike LhcSR3, PsbS accumulates very rapidly but only transiently. In order to determine the role of PsbS in NPQ and photoprotection in Chlamydomonas, we generated transplastomic strains expressing the algal or the Arabidopsis psbS gene optimized for plastid expression. Both PsbS proteins showed the ability to increase NPQ in Chlamydomonas wild-type and npq4 (lacking LhcSR3) backgrounds, but no clear photoprotection activity was observed. Quantification of PsbS and LhcSR3 in vivo indicates that PsbS is much less abundant than LhcSR3 during high light stress. Moreover, LhcSR3, unlike PsbS, also accumulates during other stress conditions. The possible role of PsbS in photoprotection is discussed. PMID:27329221

  8. Maize Iranian mosaic virus shows a descending transcript accumulation order in plant and insect hosts.

    PubMed

    Hortamani, Mozhgan; Massah, Amir; Izadpanah, Keramat

    2018-04-01

    Maize Iranian mosaic virus (MIMV) is a distinct member of the genus Nucleorhabdovirus. In this study, expression of all MIMV genes in maize for four weeks after inoculation and in inoculative planthoppers was examined using a quantitative RT-PCR (RT-qPCR) assay. Accumulation of MIMV P, gene 3, M, G and L transcripts relative to N transcripts was measured and normalized to 18S rRNA in maize plants and to the ribosomal protein S13 gene (RPS13) in planthoppers using the comparative C T method. In plants, higher levels of MIMV N transcripts were found relative to other transcripts, while MIMV L transcripts were at the lowest levels. The highest accumulation of MIMV transcripts was found at 14 days postinoculation (dpi). At 21 dpi, we found the lowest transcript levels for all genes, which increased again at 28 dpi, although in lower amounts than at 14 dpi. In Laodelphax striatellus, MIMV M, G and L transcripts accumulated at lower levels than other transcripts. The gene 3 transcript level was high in both plants and planthoppers. Our results showed that transcript accumulation for the MIMV genes was similar in both hosts and followed the pattern of sequential transcriptional attenuation from the 3' to the 5' end of the genome, similar to vertebrate rhabdoviruses. These results indicate that the regulation of virus gene transcription for this plant-infecting rhabdovirus is similar to that of some vertebrate-infecting rhabdoviruses.

  9. Molecular chaperone accumulation as a function of stress evidences adaptation to high hydrostatic pressure in the piezophilic archaeon Thermococcus barophilus.

    PubMed

    Cario, Anaïs; Jebbar, Mohamed; Thiel, Axel; Kervarec, Nelly; Oger, Phil M

    2016-07-05

    The accumulation of mannosyl-glycerate (MG), the salinity stress response osmolyte of Thermococcales, was investigated as a function of hydrostatic pressure in Thermococcus barophilus strain MP, a hyperthermophilic, piezophilic archaeon isolated from the Snake Pit site (MAR), which grows optimally at 40 MPa. Strain MP accumulated MG primarily in response to salinity stress, but in contrast to other Thermococcales, MG was also accumulated in response to thermal stress. MG accumulation peaked for combined stresses. The accumulation of MG was drastically increased under sub-optimal hydrostatic pressure conditions, demonstrating that low pressure is perceived as a stress in this piezophile, and that the proteome of T. barophilus is low-pressure sensitive. MG accumulation was strongly reduced under supra-optimal pressure conditions clearly demonstrating the structural adaptation of this proteome to high hydrostatic pressure. The lack of MG synthesis only slightly altered the growth characteristics of two different MG synthesis deletion mutants. No shift to other osmolytes was observed. Altogether our observations suggest that the salinity stress response in T. barophilus is not essential and may be under negative selective pressure, similarly to what has been observed for its thermal stress response.

  10. Molecular chaperone accumulation as a function of stress evidences adaptation to high hydrostatic pressure in the piezophilic archaeon Thermococcus barophilus

    PubMed Central

    Cario, Anaïs; Jebbar, Mohamed; Thiel, Axel; Kervarec, Nelly; Oger, Phil M.

    2016-01-01

    The accumulation of mannosyl-glycerate (MG), the salinity stress response osmolyte of Thermococcales, was investigated as a function of hydrostatic pressure in Thermococcus barophilus strain MP, a hyperthermophilic, piezophilic archaeon isolated from the Snake Pit site (MAR), which grows optimally at 40 MPa. Strain MP accumulated MG primarily in response to salinity stress, but in contrast to other Thermococcales, MG was also accumulated in response to thermal stress. MG accumulation peaked for combined stresses. The accumulation of MG was drastically increased under sub-optimal hydrostatic pressure conditions, demonstrating that low pressure is perceived as a stress in this piezophile, and that the proteome of T. barophilus is low-pressure sensitive. MG accumulation was strongly reduced under supra-optimal pressure conditions clearly demonstrating the structural adaptation of this proteome to high hydrostatic pressure. The lack of MG synthesis only slightly altered the growth characteristics of two different MG synthesis deletion mutants. No shift to other osmolytes was observed. Altogether our observations suggest that the salinity stress response in T. barophilus is not essential and may be under negative selective pressure, similarly to what has been observed for its thermal stress response. PMID:27378270

  11. Heavy metal accumulation and growth of seedlings of five forest species as influenced by soil cadmium level

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kelly, J.M.; Parker, G.R.; McFee, W.W.

    1979-07-01

    White pine (Pinus strobus L.), loblolly pine (P. taeda L.), yellow poplar (Liriodendron tulipifera L.), yellow birch (Betula alleghaniensis Britt.), and choke cherry (Prunus virginiana L.) were grown from seeds in the greenhouse for 17 weeks. Plainfield fine sand, with pretreatment cadmium, lead, copper, and zinc concentrations of 0.6, 11.4, 2.0, and 20.6 ppM, respectively, was used as the growth medium. This soil was amended with CdCl/sub 2/ to produce cadmium addition levels of 0, 15, and 100 ppM. Shoot elongation and root and shoot dry weights were reduced with increasing levels of soil cadmium. All species exhibited increased cadmiummore » content in roots and shoots in response to increased soil cadmium levels; however, content varied according to species. Root and shoot accumulations of lead, copper, and zinc also varied with species as well as cadmium concentration in the soil.« less

  12. A High Frequency Response Relaxed Eddy Accumulation Flux Measurement System for Sampling Short-Lived Biogenic Volatile Organic Compounds

    EPA Science Inventory

    A second-generation relaxed eddy accumulation system was built and tested with the capability to measure vertical biogenic volatile organic compound (VOC) fluxes at levels as low as 10 µg C m−2 hr−1. The system features a continuous, integrated gas-phase ozo...

  13. Anaerobic granule-based biofilms formation reduces propionate accumulation under high H2 partial pressure using conductive carbon felt particles.

    PubMed

    Xu, Heng; Wang, Cuiping; Yan, Kun; Wu, Jing; Zuo, Jiane; Wang, Kaijun

    2016-09-01

    Syngas based co-digestion is not only more economically attractive than separate syngas methanation but also able to upgrade biogas and increase overall CH4 amount simultaneously. However, high H2 concentration in the syngas could inhibit syntrophic degradation of propionate, resulting in propionate accumulation and even failure of the co-digestion system. In an attempt to reduce propionate accumulation via enhancing both H2 interspecies transfer (HIT) and direct interspecies electron transfer (DIET) pathways, layered granule-based biofilms induced by conductive carbon felt particles (CCFP) was employed. The results showed that propionate accumulation was effectively reduced with influent COD load up to 7gL(-1)d(-1). Two types of granule-based biofilms, namely biofilm adhered to CCFP (B-CCFP) and granules formed by self-immobilization (B-SI) were formed in the reactor. Clostridium, Syntrophobacter, Methanospirillum were possibly involved in HIT and Clostridium, Geobacter, Anaerolineaceae, Methanosaeta in DIET, both of which might be responsible for the high-rate propionate degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Seasonality of snow accumulation at Mount Wrangell, Alaska, USA

    NASA Astrophysics Data System (ADS)

    Kanamori, Syosaku; Benson, Carl S.; Truffer, Martin; Matoba, Sumito; Solie, Daniel J.; Shiraiwa, Takayuki

    We recorded the burial times of temperature sensors mounted on a specially constructed tower to determine snow accumulation during individual storms in the summit caldera of Mount Wrangell, Alaska, USA, (62°N, 144°W; 4100 m a.s.l.) during the accumulation year June 2005 to June 2006. The experiment showed most of the accumulation occurred in episodic large storms, and half of the total accumulation was delivered in late summer. The timing of individual events correlated well with storms recorded upwind, at Cordova, the closest Pacific coastal weather station (200 km south-southeast), although the magnitude of events showed only poor correlation. Hence, snow accumulation at Mount Wrangell appears to be a reflection of synoptic-scale regional weather systems. The accumulation at Mount Wrangell's summit (>2.5 m w.e.) exceeded the precipitation at Cordova. Although the direct relationship between accumulation of individual storms at the summit of Mount Wrangell and precipitation events at Cordova may be unique in the region, it is useful for interpreting ice cores obtained on Mount Wrangell. This is especially the case here because the high rate of accumulation allows high time resolution within the core.

  15. Contaminant Accumulation in Many New England Lead Pipe Scales

    EPA Science Inventory

    Previous work has shown that contaminants such as Al, As and Ra can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could conceivably result in elevated levels at consumers' taps. The objective of this s...

  16. The role of photorespiration during astaxanthin accumulation in Haematococcus pluvialis (Chlorophyceae).

    PubMed

    Zhang, Chunhui; Zhang, Litao; Liu, Jianguo

    2016-10-01

    Most previous studies on Haematococcus pluvialis have been focused on growth and astaxanthin accumulation. However, the relationships between photorespiration and astaxanthin accumulation have not been clarified. The purpose of this study was to examine the role of photorespiration during the process of astaxanthin accumulation in H. pluvialis. During astaxanthin accumulation, the astaxanthin content was reduced significantly when photorespiration was inhibited by its specific inhibitor, carboxymethoxylamine. The inhibition of photorespiration did not change the dry weight, chlorophyll content and OJIP transients during the incubation; however, the inhibition of photorespiration significantly decreased the photochemistry of photosystem II and total photosynthetic O2 evolution capacity. Moreover, the restriction in photorespiration was synchronized with a decrease of astaxanthin accumulation. These results suggest that the photorespiratory pathway in H. pluvialis can accelerate astaxanthin accumulation. We speculate that photorespiration can enhance astaxanthin accumulation in the following ways: (i) photorespiration directly affects the glycerate-3-phosphate (PGA) level, which is intrinsically related to the accumulation of astaxanthin in H. pluvialis; (ii) the photorespiratory pathway indirectly affects the PGA level by effecting the dark reactions of photosynthesis, which then results in the enhancement of astaxanthin accumulation in H. pluvialis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. High-throughput imaging method for direct assessment of GM1 ganglioside levels in mammalian cells

    PubMed Central

    Acosta, Walter; Martin, Reid; Radin, David N.; Cramer, Carole L.

    2016-01-01

    GM1-gangliosidosis is an inherited autosomal recessive disorder caused by mutations in the gene GLB1, which encodes acid β-galactosidase (β-gal). The lack of activity in this lysosomal enzyme leads to accumulation of GM1 gangliosides (GM1) in cells. We have developed a high-content-imaging method to assess GM1 levels in fibroblasts that can be used to evaluate substrate reduction in treated GLB1−/− cells [1]. This assay allows fluorescent quantification in a multi-well system which generates unbiased and statistically significant data. Fluorescently labeled Cholera Toxin B subunit (CTXB), which specifically binds to GM1 gangliosides, was used to detect in situ GM1 levels in a fixed monolayer of fibroblasts. This sensitive, rapid, and inexpensive method facilitates in vitro drug screening in a format that allows a high number of replicates using low working volumes. PMID:26958633

  18. Influence of cadmium stress on root exudates of high cadmium accumulating rice line (Oryza sativa L.).

    PubMed

    Fu, Huijie; Yu, Haiying; Li, Tingxuan; Zhang, Xizhou

    2018-04-15

    A hydroponic experiment with two different cadmium (Cd) accumulating rice lines of Lu527-8 (the high Cd accumulating rice line) and Lu527-4 (the normal rice line) was carried out to explore the links among Cd stress, root exudates and Cd accumulation. The results showed that (1) Cd stress increased quantities of organic acids, but had no effect on composition in root exudates of the two rice lines. In Cd treatments, the contents of every detected organic acid in root exudates of Lu527-8 were 1.76-2.43 times higher than those of Lu527-4. Significant positive correlations between organic acids contents and Cd contents in plants were observed in both rice lines, except that malic acid was only highly relevant to Lu527-8, but not to Lu527-4. (2) Both composition and quantities of amino acids in root exudates changed a lot under Cd stress and this change differed in two rice lines. In control, four amino acids (glutamic acid, glycine, tyrosine and histidine) were detected in two rice lines. Under Cd stress, eight amino acids in Lu527-8 and seven amino acids in Lu527-4 could be detected, among which phenylalanine was only secreted by Lu527-8 and alanine, methionine and lysine were secreted by both rice lines. The contents of those four newly secreted amino acids from Lu527-8 increased significantly with the increase of Cd dose and each had a high-positive correlation with Cd contents, but the same change did not appear in Lu527-4. The difference between two rice lines in secretion of organic acids and amino acids may be related to their different Cd uptake properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Dose accumulation of multiple high dose rate prostate brachytherapy treatments in two commercially available image registration systems.

    PubMed

    Poder, Joel; Yuen, Johnson; Howie, Andrew; Bece, Andrej; Bucci, Joseph

    2017-11-01

    The purpose of this study was to assess whether deformable image registration (DIR) is required for dose accumulation of multiple high dose rate prostate brachytherapy (HDRPBT) plans treated with the same catheter pattern on two different CT datasets. DIR was applied to 20 HDRPBT patients' planning CT images who received two treatment fractions on sequential days, on two different CT datasets, with the same implant. Quality of DIR in Velocity and MIM image registration systems was assessed by calculating the Dice Similarity Coefficient (DSC) and mean distance to agreement (MDA) for the prostate, urethra and rectum contours. Accumulated doses from each system were then calculated using the same DIR technique and dose volume histogram (DVH) parameters compared to manual addition with no DIR. The average DSC was found to be 0.83 (Velocity) and 0.84 (MIM), 0.80 (Velocity) and 0.80 (MIM), 0.80 (Velocity) and 0.81 (MIM), for the prostate, rectum and urethra contours, respectively. The average difference in calculated DVH parameters between the two systems using dose accumulation was less than 1%, and there was no statistically significant difference found between deformably accumulated doses in the two systems versus manual DVH addition with no DIR. Contour propagation using DIR in velocity and MIM was shown to be at least equivalent to inter-observer contouring variability on CT. The results also indicate that dose accumulation through manual addition of DVH parameters may be sufficient for HDRPBT treatments treated with the same catheter pattern on two different CT datasets. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  20. (13)C-metabolic flux analysis of lipid accumulation in the oleaginous fungus Mucor circinelloides.

    PubMed

    Zhao, Lina; Zhang, Huaiyuan; Wang, Liping; Chen, Haiqin; Chen, Yong Q; Chen, Wei; Song, Yuanda

    2015-12-01

    The oleaginous fungus Mucor circinelloides is of industrial interest because it can produce high levels of polyunsaturated fatty acid γ-linolenic acid. M. circinelloides CBS 277.49 is able to accumulate less than 15% of cell dry weight as lipids, while M. circinelloides WJ11 can accumulate lipid up to 36%. In order to better understand the mechanisms behind the differential lipid accumulation in these two strains, tracer experiments with (13)C-glucose were performed with the growth of M. circinelloides and subsequent gas chromatography-mass spectrometric detection of (13)C-patterns in proteinogenic amino acids was carried out to identify the metabolic network topology and estimate intracellular fluxes. Our results showed that the high oleaginous strain WJ11 had higher flux of pentose phosphate pathway and malic enzyme, lower flux in tricarboxylic acid cycle, higher flux in glyoxylate cycle and ATP: citrate lyase, together, it might provide more NADPH and substrate acetyl-CoA for fatty acid synthesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Accumulation of Carotenoids and Expression of Carotenoid Biosynthetic Genes during Maturation in Citrus Fruit1

    PubMed Central

    Kato, Masaya; Ikoma, Yoshinori; Matsumoto, Hikaru; Sugiura, Minoru; Hyodo, Hiroshi; Yano, Masamichi

    2004-01-01

    The relationship between carotenoid accumulation and the expression of carotenoid biosynthetic genes during fruit maturation was investigated in three citrus varieties, Satsuma mandarin (Citrus unshiu Marc.), Valencia orange (Citrus sinensis Osbeck), and Lisbon lemon (Citrus limon Burm.f.). We cloned the cDNAs for phytoene synthase (CitPSY), phytoene desaturase (CitPDS), ζ-carotene (car) desaturase (CitZDS), carotenoid isomerase (CitCRTISO), lycopene β-cyclase (CitLCYb), β-ring hydroxylase (CitHYb), zeaxanthin (zea) epoxidase (CitZEP), and lycopene ε-cyclase (CitLCYe) from Satsuma mandarin, which shared high identities in nucleotide sequences with Valencia orange, Lisbon lemon, and other plant species. With the transition of peel color from green to orange, the change from β,ε-carotenoid (α-car and lutein) accumulation to β,β-carotenoid (β-car, β-cryptoxanthin, zea, and violaxanthin) accumulation was observed in the flavedos of Satsuma mandarin and Valencia orange, accompanying the disappearance of CitLCYe transcripts and the increase in CitLCYb transcripts. Even in green fruit, high levels of β,ε-carotenoids and CitLCYe transcripts were not observed in the juice sacs. As fruit maturation progressed in Satsuma mandarin and Valencia orange, a simultaneous increase in the expression of genes (CitPSY, CitPDS, CitZDS, CitLCYb, CitHYb, and CitZEP) led to massive β,β-xanthophyll (β-cryptoxanthin, zea, and violaxanthin) accumulation in both the flavedo and juice sacs. The gene expression of CitCRTISO was kept low or decreased in the flavedo during massive β,β-xanthophyll accumulation. In the flavedo of Lisbon lemon and Satsuma mandarin, massive accumulation of phytoene was observed with a decrease in the transcript level for CitPDS. Thus, the carotenoid accumulation during citrus fruit maturation was highly regulated by the coordination of the expression among carotenoid biosynthetic genes. In this paper, the mechanism leading to diversity in

  2. The fate of fertilizer nitrogen in a high nitrate accumulated agricultural soil

    PubMed Central

    Quan, Zhi; Huang, Bin; Lu, Caiyan; Shi, Yi; Chen, Xin; Zhang, Haiyang; Fang, Yunting

    2016-01-01

    Well-acclimatized nitrifiers in high-nitrate agricultural soils can quickly nitrify NH4+ into NO3− subject to leaching and denitrifying loss. A 120-day incubation experiment was conducted using a greenhouse soil to explore the fates of applied fertilizer N entering into seven soil N pools and to examine if green manure (as ryegrass) co-application can increase immobilization of the applied N into relatively stable N pools and thereby reduce NO3− accumulation and loss. We found that 87–92% of the applied 15N-labelled NH4+ was rapidly recovered as NO3− since day 3 and only 2–4% as microbial biomass and soil organic matter (SOM), while ryegrass co-application significantly decreased its recovery as NO3− but enhanced its recovery as SOM (17%) at the end of incubation. The trade-off relationship between 15N recoveries in microbial biomass and SOM indicated that ryegrass co-application stabilized newly immobilized N via initial microbial uptake and later breakdown. Nevertheless, ryegrass application didn’t decrease soil total NO3− accumulation due to its own decay. Our results suggest that green manure co-application can increase immobilization of applied N into stable organic N via microbial turnover, but the quantity and quality of green manure should be well considered to reduce N release from itself. PMID:26868028

  3. Proteomic and Metabolomic Analyses of Leaf from Clematis terniflora DC. Exposed to High-Level Ultraviolet-B Irradiation with Dark Treatment.

    PubMed

    Yang, Bingxian; Wang, Xin; Gao, Cuixia; Chen, Meng; Guan, Qijie; Tian, Jingkui; Komatsu, Setsuko

    2016-08-05

    Clematis terniflora DC. has potential pharmaceutical value; on the contrary, high-level UV-B irradiation with dark treatment led to the accumulation of secondary metabolites. Metabolomic and proteomic analyses of leaf of C. terniflora were performed to investigate the systematic response mechanisms to high-level UV-B irradiation with dark treatment. Metabolites related to carbohydrates, fatty acids, and amino acids and/or proteins related to stress, cell wall, and amino acid metabolism were gradually increased in response to high-level UV-B irradiation with dark treatment. On the basis of cluster analysis and mapping of proteins related to amino acid metabolism, the abundances of S-adenosylmethionine synthetase and cysteine synthase as well as 1,1-diphenyl-2-picrylhydrazyl scavenging activity were gradually increased in response to high-level UV-B irradiation with dark treatment. Furthermore, the abundance of dihydrolipoyl dehydrogenase/glutamate dehydrogenase and the content of γ-aminobutyric acid were also increased following high-level UV-B irradiation with dark treatment. Taken together, these results suggest that high-level UV-B irradiation with dark treatment induces the activation of reactive oxygen species scavenging system and γ-aminobutyric acid shunt pathway in leaf of C. terniflora.

  4. Constant-Differential-Pressure Two-Fluid Accumulator

    NASA Technical Reports Server (NTRS)

    Piecuch, Benjamin; Dalton, Luke T.

    2010-01-01

    A two-fluid accumulator has been designed, built, and demonstrated to provide an acceptably close approximation to constant differential static pressure between two fluids over the full ranges of (1) accumulator stroke, (2) rates of flow of the fluids, and (3) common static pressure applied to the fluids. Prior differential- pressure two-fluid accumulators are generally not capable of maintaining acceptably close approximations to constant differential pressures. The inadequacies of a typical prior differential-pressure two-fluid accumulator can be summarized as follows: The static differential pressure is governed by the intrinsic spring rate (essentially, the stiffness) of an accumulator tank. The spring rate can be tailored through selection of the tank-wall thickness, selection of the number and/or shape of accumulator convolutions, and/or selection of accumulator material(s). Reliance on the intrinsic spring rate of the tank results in three severe limitations: (1) The spring rate and the expulsion efficiency tend to be inversely proportional to each other: that is to say, as the stiffness (and thus the differential pressure) is increased, the range of motion of the accumulator is reduced. (2) As the applied common static pressure increases, the differential pressure tends to decrease. An additional disadvantage, which may or may not be considered limiting, depending on the specific application, is that an increase in stiffness entails an increase in weight. (3) The additional weight required by a low expulsion efficiency accumulator eliminates the advantage given to such gas storage systems. The high expulsion efficiency provided by this two-fluid accumulator allows for a lightweight, tightly packaged system, which can be used in conjunction with a fuel cell-based system.

  5. RELATING ACCUMULATOR MODEL PARAMETERS AND NEURAL DYNAMICS

    PubMed Central

    Purcell, Braden A.; Palmeri, Thomas J.

    2016-01-01

    Accumulator models explain decision-making as an accumulation of evidence to a response threshold. Specific model parameters are associated with specific model mechanisms, such as the time when accumulation begins, the average rate of evidence accumulation, and the threshold. These mechanisms determine both the within-trial dynamics of evidence accumulation and the predicted behavior. Cognitive modelers usually infer what mechanisms vary during decision-making by seeing what parameters vary when a model is fitted to observed behavior. The recent identification of neural activity with evidence accumulation suggests that it may be possible to directly infer what mechanisms vary from an analysis of how neural dynamics vary. However, evidence accumulation is often noisy, and noise complicates the relationship between accumulator dynamics and the underlying mechanisms leading to those dynamics. To understand what kinds of inferences can be made about decision-making mechanisms based on measures of neural dynamics, we measured simulated accumulator model dynamics while systematically varying model parameters. In some cases, decision- making mechanisms can be directly inferred from dynamics, allowing us to distinguish between models that make identical behavioral predictions. In other cases, however, different parameterized mechanisms produce surprisingly similar dynamics, limiting the inferences that can be made based on measuring dynamics alone. Analyzing neural dynamics can provide a powerful tool to resolve model mimicry at the behavioral level, but we caution against drawing inferences based solely on neural analyses. Instead, simultaneous modeling of behavior and neural dynamics provides the most powerful approach to understand decision-making and likely other aspects of cognition and perception. PMID:28392584

  6. Sodium accumulation in Atriplex. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Norton, J.A.; Caldwell, M.M.; Richardson, S.G.

    1984-09-01

    This study was undertaken to determine the ecological significance and the significance to arid land reclamation of sodium accumulation and nonaccumulation in Atriplex. There was a continuum in the genetic tendency of Atriplex canescens to accumulate sodium, from populations which accumulated almost no sodium to populations which accumulated up to 7% in the leaves. There were also substantial differences in sodium uptake between populations of A. tridentata, A. falcata and A. gardneri, with some populations having less than 0.1% leaf sodium and other populations having up to 5 or 6%. In three experiments (a field study, a greenhouse pot studymore » and a hydroponics study) there were no significant differences in salinity tolerance between sodium accumulating and nonaccumulating A. canescens: both genotypes were highly salt tolerant. There was a significant buildup of sodium in the soil beneath sodium accumulating Atriplex plants, both in natural populations and on revegetated oil shale study plots. The sodium buildup was not sufficient to be detrimental to the growth or establishment of most herbaceous species, but with older Atriplex plants or with more saline soil, the buildup could potentially be detrimental. 14 references, 42 figures, 3 tables.« less

  7. Relationship of Area of Soft Drusen in Retina with Cerebral Amyloid-β Accumulation and Blood Amyloid-β Level in the Elderly.

    PubMed

    Shoda, Chiho; Kitagawa, Yorihisa; Shimada, Hiroyuki; Yuzawa, Mitsuko; Tateno, Amane; Okubo, Yoshiro

    2018-01-01

    Histopathological studies have confirmed that soft drusen contains amyloid-β (Aβ). To examine the relationship between the area of soft drusen in the macular area and cerebral Aβ accumulation or plasma Aβ level in elderly persons without dementia. Fourteen consecutive patients (18 eyes) aged ≥50 years with macular soft drusen were studied prospectively. From color fundus photographs, the area of soft drusen (pixel) within a 6,000 μm diameter with the macula as center was measured. Standard uptake value ratio (SUVR) was obtained from positron emission tomography using florbetapir, which indicates the ratio of cerebral cortical-to-cerebellar Aβ accumulation. Ratio of plasma Aβ1-42 to Aβ1-40 level was calculated. Mean age was 73.3±7.6 years. The soft drusen area was 4.32±2.42 mm2. The SUVR was 1.08±0.15. Plasma Aβ1-42/Aβ1-40 ratio was 0.17±0.08. When SUVR ≥1.10 was defined as positive and <1.10 as negative, the soft drusen area in SUVR-positive patients (6.19±1.14 mm2) was significantly (p = 0.0043) larger than that in SUVR-negative patients (3.13±2.27 mm2). Multivariate regression analysis showed that SUVR positivity correlated with soft drusen area (p = 0.0484) and with Voxel-based Specific Regional Analysis System for Alzheimer's Disease score (p = 0.0360). However, there was no correlation with gender (p = 0.1921), age (p = 0.2361), Alzheimer's Disease Assessment Scale score (p = 0.6310), Mini-Mental State Examination score (p = 0.4246), or plasma Aβ1-42/Aβ1-40 ratio (p = 0.8398). Among elderly persons without dementia, the area of soft drusen was larger in those with more extensive cerebral Aβ accumulation. The area of soft drusen may be a biomarker of cerebral Aβ accumulation.

  8. High hydrostatic pressure leads to free radicals accumulation in yeast cells triggering oxidative stress.

    PubMed

    Bravim, Fernanda; Mota, Mainã M; Fernandes, A Alberto R; Fernandes, Patricia M B

    2016-08-01

    Saccharomyces cerevisiae is a unicellular organism that during the fermentative process is exposed to a variable environment; hence, resistance to multiple stress conditions is a desirable trait. The stress caused by high hydrostatic pressure (HHP) in S. cerevisiae resembles the injuries generated by other industrial stresses. In this study, it was confirmed that gene expression pattern in response to HHP displays an oxidative stress response profile which is expanded upon hydrostatic pressure release. Actually, reactive oxygen species (ROS) concentration level increased in yeast cells exposed to HHP treatment and an incubation period at room pressure led to a decrease in intracellular ROS concentration. On the other hand, ethylic, thermic and osmotic stresses did not result in any ROS accumulation in yeast cells. Microarray analysis revealed an upregulation of genes related to methionine metabolism, appearing to be a specific cellular response to HHP, and not related to other stresses, such as heat and osmotic stresses. Next, we investigated whether enhanced oxidative stress tolerance leads to enhanced tolerance to HHP stress. Overexpression of STF2 is known to enhance tolerance to oxidative stress and we show that it also leads to enhanced tolerance to HHP stress. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. High-Level Binocular Rivalry Effects

    PubMed Central

    Wolf, Michal; Hochstein, Shaul

    2011-01-01

    Binocular rivalry (BR) occurs when the brain cannot fuse percepts from the two eyes because they are different. We review results relating to an ongoing controversy regarding the cortical site of the BR mechanism. Some BR qualities suggest it is low-level: (1) BR, as its name implies, is usually between eyes and only low-levels have access to utrocular information. (2) All input to one eye is suppressed: blurring doesn’t stimulate accommodation; pupilary constrictions are reduced; probe detection is reduced. (3) Rivalry is affected by low-level attributes, contrast, spatial frequency, brightness, motion. (4) There is limited priming due to suppressed words or pictures. On the other hand, recent studies favor a high-level mechanism: (1) Rivalry occurs between patterns, not eyes, as in patchwork rivalry or a swapping paradigm. (2) Attention affects alternations. (3) Context affects dominance. There is conflicting evidence from physiological studies (single cell and fMRI) regarding cortical level(s) of conscious perception. We discuss the possibility of multiple BR sites and theoretical considerations that rule out this solution. We present new data regarding the locus of the BR switch by manipulating stimulus semantic content or high-level characteristics. Since these variations are represented at higher cortical levels, their affecting rivalry supports high-level BR intervention. In Experiment I, we measure rivalry when one eye views words and the other non-words and find significantly longer dominance durations for non-words. In Experiment II, we find longer dominance times for line drawings of simple, structurally impossible figures than for similar, possible objects. In Experiment III, we test the influence of idiomatic context on rivalry between words. Results show that generally words within their idiomatic context have longer mean dominance durations. We conclude that BR has high-level cortical influences, and may be controlled by a high-level mechanism

  10. Evidence accumulation in obsessive-compulsive disorder: the role of uncertainty and monetary reward on perceptual decision-making thresholds.

    PubMed

    Banca, Paula; Vestergaard, Martin D; Rankov, Vladan; Baek, Kwangyeol; Mitchell, Simon; Lapa, Tatyana; Castelo-Branco, Miguel; Voon, Valerie

    2015-03-13

    The compulsive behaviour underlying obsessive-compulsive disorder (OCD) may be related to abnormalities in decision-making. The inability to commit to ultimate decisions, for example, patients unable to decide whether their hands are sufficiently clean, may reflect failures in accumulating sufficient evidence before a decision. Here we investigate the process of evidence accumulation in OCD in perceptual discrimination, hypothesizing enhanced evidence accumulation relative to healthy volunteers. Twenty-eight OCD patients and thirty-five controls were tested with a low-level visual perceptual task (random-dot-motion task, RDMT) and two response conflict control tasks. Regression analysis across different motion coherence levels and Hierarchical Drift Diffusion Modelling (HDDM) were used to characterize response strategies between groups in the RDMT. Patients required more evidence under high uncertainty perceptual contexts, as indexed by longer response time and higher decision boundaries. HDDM, which defines a decision when accumulated noisy evidence reaches a decision boundary, further showed slower drift rate towards the decision boundary reflecting poorer quality of evidence entering the decision process in patients under low uncertainty. With monetary incentives emphasizing speed and penalty for slower responses, patients decreased the decision thresholds relative to controls, accumulating less evidence in low uncertainty. These findings were unrelated to visual perceptual deficits and response conflict. This study provides evidence for impaired decision-formation processes in OCD, with a differential influence of high and low uncertainty contexts on evidence accumulation (decision threshold) and on the quality of evidence gathered (drift rates). It further emphasizes that OCD patients are sensitive to monetary incentives heightening speed in the speed-accuracy tradeoff, improving evidence accumulation.

  11. Selenium accumulation and metabolism in algae.

    PubMed

    Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

    2017-08-01

    Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Increased ethanol accumulation from glucose via reduction of ATP level in a recombinant strain of Saccharomyces cerevisiae overexpressing alkaline phosphatase.

    PubMed

    Semkiv, Marta V; Dmytruk, Kostyantyn V; Abbas, Charles A; Sibirny, Andriy A

    2014-05-15

    The production of ethyl alcohol by fermentation represents the largest scale application of Saccharomyces cerevisiae in industrial biotechnology. Increased worldwide demand for fuel bioethanol is anticipated over the next decade and will exceed 200 billion liters from further expansions. Our working hypothesis was that the drop in ATP level in S. cerevisiae cells during alcoholic fermentation should lead to an increase in ethanol production (yield and productivity) with a greater amount of the utilized glucose converted to ethanol. Our approach to achieve this goal is to decrease the intracellular ATP level via increasing the unspecific alkaline phosphatase activity. Intact and truncated versions of the S. cerevisiae PHO8 gene coding for vacuolar or cytosolic forms of alkaline phosphatase were fused with the alcohol dehydrogenase gene (ADH1) promoter. The constructed expression cassettes used for transformation vectors also contained the dominant selective marker kanMX4 and S. cerevisiae δ-sequence to facilitate multicopy integration to the genome. Laboratory and industrial ethanol producing strains BY4742 and AS400 overexpressing vacuolar form of alkaline phosphatase were characterized by a slightly lowered intracellular ATP level and biomass accumulation and by an increase in ethanol productivity (13% and 7%) when compared to the parental strains. The strains expressing truncated cytosolic form of alkaline phosphatase showed a prolonged lag-phase, reduced biomass accumulation and a strong defect in ethanol production. Overexpression of vacuolar alkaline phosphatase leads to an increased ethanol yield in S. cerevisiae.

  13. RPython high-level synthesis

    NASA Astrophysics Data System (ADS)

    Cieszewski, Radoslaw; Linczuk, Maciej

    2016-09-01

    The development of FPGA technology and the increasing complexity of applications in recent decades have forced compilers to move to higher abstraction levels. Compilers interprets an algorithmic description of a desired behavior written in High-Level Languages (HLLs) and translate it to Hardware Description Languages (HDLs). This paper presents a RPython based High-Level synthesis (HLS) compiler. The compiler get the configuration parameters and map RPython program to VHDL. Then, VHDL code can be used to program FPGA chips. In comparison of other technologies usage, FPGAs have the potential to achieve far greater performance than software as a result of omitting the fetch-decode-execute operations of General Purpose Processors (GPUs), and introduce more parallel computation. This can be exploited by utilizing many resources at the same time. Creating parallel algorithms computed with FPGAs in pure HDL is difficult and time consuming. Implementation time can be greatly reduced with High-Level Synthesis compiler. This article describes design methodologies and tools, implementation and first results of created VHDL backend for RPython compiler.

  14. Heavy metals in wild marine fish from South China Sea: levels, tissue- and species-specific accumulation and potential risk to humans.

    PubMed

    Liu, Jin-Ling; Xu, Xiang-Rong; Ding, Zhen-Hua; Peng, Jia-Xi; Jin, Ming-Hua; Wang, You-Shao; Hong, Yi-Guo; Yue, Wei-Zhong

    2015-10-01

    Heavy metal pollution in marine fish has become an important worldwide concern, not only because of the threat to fish in general, but also due to human health risks associated with fish consumption. To investigate the occurrence of heavy metals in marine fish species from the South China Sea, 14 fish species were collected along the coastline of Hainan China during the spring of 2012 and examined for species- and tissue-specific accumulation. The median concentrations of Cd, Cr, Cu, Zn, Pb and As in muscle tissue of the examined fish species were not detectable (ND), 2.02, 0.24, 2.64, 0.025, and 1.13 mg kg(-1) wet weight, respectively. Levels of Cu, Zn, Cd and Cr were found to be higher in the liver and gills than in muscle, while Pb was preferentially accumulated in the gills. Differing from other heavy metals, As did not exhibit tissue-specific accumulation. Inter-species differences of heavy metal accumulation were attributed to the different habitat and diet characteristics of marine fish. Human dietary exposure assessment suggested that the amounts of both Cr and As in marine wild fish collected from the sites around Hainan, China were not compliant with the safety standard of less than 79.2 g d(-1) for wild marine fish set by the Joint FAO/WHO Expert Committee on Food Additives. Further research to identify the explicit sources of Cr and As in marine fish from South China Sea should be established.

  15. From the clouds to the ground - snow precipitation patterns vs. snow accumulation patterns

    NASA Astrophysics Data System (ADS)

    Gerber, Franziska; Besic, Nikola; Mott, Rebecca; Gabella, Marco; Germann, Urs; Bühler, Yves; Marty, Mauro; Berne, Alexis; Lehning, Michael

    2017-04-01

    Knowledge about snow distribution and snow accumulation patterns is important and valuable for different applications such as the prediction of seasonal water resources or avalanche forecasting. Furthermore, accumulated snow on the ground is an important ground truth for validating meteorological and climatological model predictions of precipitation in high mountains and polar regions. Snow accumulation patterns are determined by many different processes from ice crystal nucleation in clouds to snow redistribution by wind and avalanches. In between, snow precipitation undergoes different dynamical and microphysical processes, such as ice crystal growth, aggregation and riming, which determine the growth of individual particles and thereby influence the intensity and structure of the snowfall event. In alpine terrain the interaction of different processes and the topography (e.g. lifting condensation and low level cloud formation, which may result in a seeder-feeder effect) may lead to orographic enhancement of precipitation. Furthermore, the redistribution of snow particles in the air by wind results in preferential deposition of precipitation. Even though orographic enhancement is addressed in numerous studies, the relative importance of micro-physical and dynamically induced mechanisms on local snowfall amounts and especially snow accumulation patterns is hardly known. To better understand the relative importance of different processes on snow precipitation and accumulation we analyze snowfall and snow accumulation between January and March 2016 in Davos (Switzerland). We compare MeteoSwiss operational weather radar measurements on Weissfluhgipfel to a spatially continuous snow accumulation map derived from airborne digital sensing (ADS) snow height for the area of Dischma valley in the vicinity of the weather radar. Additionally, we include snow height measurements from automatic snow stations close to the weather radar. Large-scale radar snow accumulation

  16. Regulation of S-like ribonuclease levels in Arabidopsis. Antisense inhibition of RNS1 or RNS2 elevates anthocyanin accumulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bariola, P.A.; MacIntosh, G.C.; Green, P.J.

    1999-01-01

    The S-like ribonucleases (RNases) RNS1 and RNS2 of Arabidopsis are members of the widespread T{sub 2} ribonuclease family, whose members also include the S-RNases, involved in gametophytic self-incompatibility in plants. Both RNS1 and RNS2 mRNAs have been shown previously to be induced by inorganic phosphate (Pi) starvation. In this study the authors examined this regulation at the protein level and determined the effects of diminishing RNS1 and RNS2 expression using antisense techniques. The Pi-starvation control of RNS1 and RNS2 was confirmed using antibodies specific for each protein. These specific antibodies also demonstrated that RNS1 is secreted, whereas RNS2 is intracellular.more » By introducing antisense constructs, mRNA accumulation was inhibited by up to 90% for RNS1 and up to 65% for NS2. These plants contained abnormally high levels of anthocyanins, the production of which is often associated with several forms of stress, including Pi starvation. This effect demonstrates that diminishing the amounts of either RNS1 or RNS2 leads to effects that cannot be compensated for by the actions of other RNases, even though Arabidopsis contains a large number of different RNase activities. These results, together with the differential localization of the proteins, imply that RNS1 and RNS2 have distinct functions in the plant.« less

  17. Elevated CO2-mitigation of high temperature stress associated with maintenance of positive carbon balance and carbohydrate accumulation in Kentucky bluegrass.

    PubMed

    Song, Yali; Yu, Jingjin; Huang, Bingru

    2014-01-01

    Elevated CO2 concentration may promote plant growth while high temperature is inhibitory for C3 plant species. The interactive effects of elevated CO2 and high temperatures on C3 perennial grass growth and carbon metabolism are not well documented. Kentucky bluegrass (Poa pratensis) plants were exposed to two CO2 levels (400 and 800 μmol mol-1) and five temperatures (15/12, 20/17, 25/22, 30/27, 35/32°C, day/night) in growth chambers. Increasing temperatures to 25°C and above inhibited leaf photosynthetic rate (Pn) and shoot and root growth, but increased leaf respiration rate (R), leading to a negative carbon balance and a decline in soluble sugar content under ambient CO2. Elevated CO2 did not cause shift of optimal temperatures in Kentucky bluegrass, but promoted Pn, shoot and root growth under all levels of temperature (15, 20, 25, 30, and 35°C) and mitigated the adverse effects of severe high temperatures (30 and 35°C). Elevated CO2-mitigation of adverse effects of high temperatures on Kentucky bluegrass growth could be associated with the maintenance of a positive carbon balance and the accumulation of soluble sugars and total nonstructural carbohydrates through stimulation of Pn and suppression of R and respiratory organic acid metabolism.

  18. The Csr System Regulates Escherichia coli Fitness by Controlling Glycogen Accumulation and Energy Levels.

    PubMed

    Morin, Manon; Ropers, Delphine; Cinquemani, Eugenio; Portais, Jean-Charles; Enjalbert, Brice; Cocaign-Bousquet, Muriel

    2017-10-31

    In the bacterium Escherichia coli , the posttranscriptional regulatory system Csr was postulated to influence the transition from glycolysis to gluconeogenesis. Here, we explored the role of the Csr system in the glucose-acetate transition as a model of the glycolysis-to-gluconeogenesis switch. Mutations in the Csr system influence the reorganization of gene expression after glucose exhaustion and disturb the timing of acetate reconsumption after glucose exhaustion. Analysis of metabolite concentrations during the transition revealed that the Csr system has a major effect on the energy levels of the cells after glucose exhaustion. This influence was demonstrated to result directly from the effect of the Csr system on glycogen accumulation. Mutation in glycogen metabolism was also demonstrated to hinder metabolic adaptation after glucose exhaustion because of insufficient energy. This work explains how the Csr system influences E. coli fitness during the glycolysis-gluconeogenesis switch and demonstrates the role of glycogen in maintenance of the energy charge during metabolic adaptation. IMPORTANCE Glycogen is a polysaccharide and the main storage form of glucose from bacteria such as Escherichia coli to yeasts and mammals. Although its function as a sugar reserve in mammals is well documented, the role of glycogen in bacteria is not as clear. By studying the role of posttranscriptional regulation during metabolic adaptation, for the first time, we demonstrate the role of sugar reserve played by glycogen in E. coli Indeed, glycogen not only makes it possible to maintain sufficient energy during metabolic transitions but is also the key component in the capacity of cells to resume growth. Since the essential posttranscriptional regulatory system Csr is a major regulator of glycogen accumulation, this work also sheds light on the central role of posttranscriptional regulation in metabolic adaptation. Copyright © 2017 Morin et al.

  19. Impact of slope inclination on salt accumulation

    NASA Astrophysics Data System (ADS)

    Nachshon, Uri

    2017-04-01

    Field measurements indicated on high variability in salt accumulation along natural and cultivated slopes, even for relatively homogeneous soil conditions. It was hypothesised that slope inclination has an impact on the location of salt accumulation along the slope. A set of laboratory experiments and numerical models were used to explore the impact of slope inclination on salt accumulation. It was shown, experimentally, that for conditions of saline water source at the lower boundary of the slope - salt accumulates in low concentrations and homogeneously along the entire slope, for moderate slopes. However, as inclination increases high salt concentrations were observed at the upper parts of the slope, leaving the lower parts of the slope relatively free of salt. The traditional flow and transport models did not predict the experimental observations as they indicated also for the moderate slopes on salt accumulation in the elevated parts of the slope, away of the saline water source. Consequently - a conceptual model was raised to explain the laboratory observations. It was suggested that the interactions between slope angle, evaporation rates, hydraulic conductivity of the medium and distribution of wetness along the slope affect the saline water flow path through the medium. This lead to preferential flow path close to the soil-atmosphere interface for the steep slopes, which leads to constant wash of the salts from the evaporation front upward towards the slope upper parts, whereas for the moderate slopes, flow path is below the soil-atmosphere interface, therefore salt that accumulates at the evaporation front is not being transported upward. Understanding of salt dynamics along slopes is important for agricultural and natural environments, as well as for civil engineering purposes. Better understanding of the salt transport processes along slopes will improve our ability to minimize and to cope with soil salinization processes. The laboratory experiments and

  20. Aluminium Accumulation and Intra-Tree Distribution Patterns in Three Arbor aluminosa (Symplocos) Species from Central Sulawesi

    PubMed Central

    Schmitt, Marco; Boras, Sven; Tjoa, Aiyen; Watanabe, Toshihiro; Jansen, Steven

    2016-01-01

    Accumulation of Aluminium (Al) at concentrations far above 1,000 mg kg-1 in aboveground plant tissues of Arbor aluminosa (Symplocos) species is the main reason why traditional Indonesian weavers rely on their leaves and bark as a mordant for dyeing textile. Recently, Symplocos species have become a flagship species for the conservation efforts of weaving communities due to their traditionally non-sustainable sampling and increasing demand for Symplocos plant material. Here we investigated Symplocos odoratissima, S. ophirensis and S. ambangensis at three montane rainforest sites in Central Sulawesi to measure Al levels in different tissues and organs. The highest Al concentrations were found in old leaves (24,180 ± 7,236 mg·kg-1 dry weight, mean ± SD), while young leaves had significantly lower Al levels (20,708 ± 7,025 mg·kg-1). Al accumulation was also lower in bark and wood tissue of the trunk (17,231 ± 8,356 mg·kg-1 and 5,181 ± 2,032 mg·kg-1, respectively). Two Al excluding species (Syzigium sp. and Lithocarpus sp.) contained only high Al levels in their roots. Moreover, no difference was found in soil pH (4.7 ± 0.61) and nutrient (K, Ca, Fe, Mg) availability at different soil levels and within or outside the crown of Symplocos trees, except for the upper soil layer. Furthermore, a positive and significant correlation between Al and Ca concentrations was found at the whole plant level for Symplocos, and at the leaf level for S. ophirensis and S. ambangensis, suggesting a potential role of Ca in Al uptake and/or detoxification within the plant. Our results provide evidence for strong Al accumulation in Symplocos species and illustrate that both Al accumulation and exclusion represent two co-occurring strategies of montane rainforest plants for dealing with Al toxicity. Indonesian weavers should be encouraged to harvest old leaves, which have the most efficient mordant capacity due to high Al concentrations. PMID:26871698

  1. Design Analysis of the Ares 1 Pogo Accumulator

    NASA Technical Reports Server (NTRS)

    Swanson, Luke A.; Giel, Thomas V.

    2009-01-01

    Several accumulator designs and gas charge systems are considered in order to suppress POGO within the Ares I vehicle Upper Stage Liquid Ox ygen System. The thermodynamic and flow analysis completed to evaluat e candidate designs are presented and the results are used to evaluat e the ability of each concept to meet the levied suppression requirements. One annular accumulator design meets all suppression requirement s while also providing manufacturability and operability advantages. Of the two proposed charge systems to provide and maintain gas within the accumulator, a passive level control design meets the charge req uirements and maximizes reliability.

  2. Soil and biomass carbon re-accumulation after landslide disturbances

    NASA Astrophysics Data System (ADS)

    Schomakers, Jasmin; Jien, Shih-Hao; Lee, Tsung-Yu; Huang-Chuan, Jr.; Hseu, Zeng-Yei; Lin, Zan Liang; Lee, Li-Chin; Hein, Thomas; Mentler, Axel; Zehetner, Franz

    2017-07-01

    In high-standing islands of the Western Pacific, typhoon-triggered landslides occasionally strip parts of the landscape of its vegetative cover and soil layer and export large amounts of biomass and soil organic carbon (OC) from land to the ocean. After such disturbances, new vegetation colonizes the landslide scars and OC starts to re-accumulate. In the subtropical mountains of Taiwan and in other parts of the world, bamboo (Bambusoideae) species may invade at a certain point in the succession of recovering landslide scars. Bamboo has a high potential for carbon sequestration because of its fast growth and dense rooting system. However, it is still largely unknown how these properties translate into soil OC re-accumulation rates after landslide disturbance. In this study, a chronosequence was established on four former landslide scars in the Central Mountain Range of Taiwan, ranging in age from 6 to 41 years post disturbance as determined by landslide mapping from remote sensing. The younger landslide scars were colonized by Miscanthus floridulus, while after approx. 15 to 20 years of succession, bamboo species (Phyllostachys) were dominating. Biomass and soil OC stocks were measured on the recovering landslide scars and compared to an undisturbed Cryptomeria japonica forest stand in the area. After initially slow re-vegetation, biomass carbon accumulated in Miscanthus stands with mean annual accretion rates of 2 ± 0.5 Mg C ha- 1 yr- 1. Biomass carbon continued to increase after bamboo invasion and reached 40% of that in the reference forest site after 41 years of landslide recovery. Soil OC accumulation rates were 2.0 Mg C ha- 1 yr- 1, 6 to 41 years post disturbance reaching 64% of the level in the reference forest. Our results from this in-situ study suggest that recovering landslide scars are strong carbon sinks once an initial lag period of vegetation re-establishment is overcome.

  3. In C. elegans, high levels of dsRNA allow RNAi in the absence of RDE-4.

    PubMed

    Habig, Jeffrey W; Aruscavage, P Joseph; Bass, Brenda L

    2008-01-01

    C. elegans Dicer requires an accessory double-stranded RNA binding protein, RDE-4, to enact the first step of RNA interference, the cleavage of dsRNA to produce siRNA. While RDE-4 is typically essential for RNAi, we report that in the presence of high concentrations of trigger dsRNA, rde-4 deficient animals are capable of silencing a transgene. By multiple criteria the silencing occurs by the canonical RNAi pathway. For example, silencing is RDE-1 dependent and exhibits a decrease in the targeted mRNA in response to an increase in siRNA. We also find that high concentrations of dsRNA trigger lead to increased accumulation of primary siRNAs, consistent with the existence of a rate-limiting step during the conversion of primary to secondary siRNAs. Our studies also revealed that transgene silencing occurs at low levels in the soma, even in the presence of ADARs, and that at least some siRNAs accumulate in a temperature-dependent manner. We conclude that an RNAi response varies with different conditions, and this may allow an organism to tailor a response to specific environmental signals.

  4. In C. elegans, High Levels of dsRNA Allow RNAi in the Absence of RDE-4

    PubMed Central

    Habig, Jeffrey W.; Aruscavage, P. Joseph; Bass, Brenda L.

    2008-01-01

    C. elegans Dicer requires an accessory double-stranded RNA binding protein, RDE-4, to enact the first step of RNA interference, the cleavage of dsRNA to produce siRNA. While RDE-4 is typically essential for RNAi, we report that in the presence of high concentrations of trigger dsRNA, rde-4 deficient animals are capable of silencing a transgene. By multiple criteria the silencing occurs by the canonical RNAi pathway. For example, silencing is RDE-1 dependent and exhibits a decrease in the targeted mRNA in response to an increase in siRNA. We also find that high concentrations of dsRNA trigger lead to increased accumulation of primary siRNAs, consistent with the existence of a rate-limiting step during the conversion of primary to secondary siRNAs. Our studies also revealed that transgene silencing occurs at low levels in the soma, even in the presence of ADARs, and that at least some siRNAs accumulate in a temperature-dependent manner. We conclude that an RNAi response varies with different conditions, and this may allow an organism to tailor a response to specific environmental signals. PMID:19112503

  5. Effects of acute chlorpyrifos exposure on in vivo acetylcholine accumulation in rat striatum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karanth, Subramanya; Liu, Jing; Mirajkar, Nikita

    2006-10-01

    This study examined the acute effects of chlorpyrifos (CPF) on cholinesterase inhibition and acetylcholine levels in the striatum of freely moving rats using in vivo microdialysis. Adult, male Sprague-Dawley rats were treated with vehicle (peanut oil, 2 ml/kg) or CPF (84, 156 or 279 mg/kg, sc) and functional signs of toxicity, body weight and motor activity recorded. Microdialysis was conducted at 1, 4 and 7 days after CPF exposure for measurement of acetylcholine levels in striatum. Rats were then sacrificed and the contralateral striatum and diaphragm were collected for biochemical measurements. Few overt signs of cholinergic toxicity were noted inmore » any rats. Body weight gain was significantly affected in the high-dose (279 mg/kg) group only, while motor activity (nocturnal rearing) was significantly reduced in all CPF-treated groups at one day (84 mg/kg) or from 1-4 days (156 and 279 mg/kg) after dosing. Cholinesterase activities in both diaphragm and striatum were markedly inhibited (50-92%) in a time-dependent manner, but there were relatively minimal dose-related changes. In contrast, time- and dose-dependent changes in striatal acetylcholine levels were noted, with significantly higher levels noted in the high-dose group compared to other groups. Maximal increases in striatal acetylcholine levels were observed at 4-7 days after dosing (84 mg/kg, 7-9-fold; 156 mg/kg, 10-13-fold; 279 mg/kg, 35-57-fold). Substantially higher acetylcholine levels were noted when an exogenous cholinesterase inhibitor was included in the perfusion buffer, but CPF treatment-related differences were substantially lower in magnitude under those conditions. The results suggest that marked differences in acetylcholine accumulation can occur with dosages of CPF eliciting relatively similar degrees of cholinesterase inhibition. Furthermore, the minimal expression of classic signs of cholinergic toxicity in the presence of extensive brain acetylcholine accumulation suggests that

  6. Increased IL-15 Production and Accumulation of Highly Differentiated CD8+ Effector/Memory T Cells in the Bone Marrow of Persons with Cytomegalovirus

    PubMed Central

    Pangrazzi, Luca; Naismith, Erin; Meryk, Andreas; Keller, Michael; Jenewein, Brigitte; Trieb, Klemens; Grubeck-Loebenstein, Beatrix

    2017-01-01

    Cytomegalovirus (CMV) has been described as a contributor to immunosenescence, thus exacerbating age-related diseases. In persons with latent CMV infection, the CD8+ T cell compartment is irreversibly changed, leading to the accumulation of highly differentiated virus-specific CD8+ T cells in the peripheral blood. The bone marrow (BM) has been shown to play a major role in the long-term survival of antigen-experienced T cells. Effector CD8+ T cells are preferentially maintained by the cytokine IL-15, the expression of which increases in old age. However, the impact of CMV on the phenotype of effector CD8+ T cells and on the production of T cell survival molecules in the BM is not yet known. We now show, using BM samples obtained from persons who underwent hip replacement surgery because of osteoarthrosis, that senescent CD8+ TEMRA cells with a bright expression of CD45RA and a high responsiveness to IL-15 accumulate in the BM of CMV-infected persons. A negative correlation was found between CMV antibody (Ab) titers in the serum and the expression of CD28 and IL-7Rα in CD8+ TEMRAbright cells. Increased IL-15 mRNA levels were observed in the BM of CMV+ compared to CMV− persons, being particularly high in old seropositive individuals. In summary, our results indicate that a BM environment rich in IL-15 may play an important role in the maintenance of highly differentiated CD8+ T cells generated after CMV infection. PMID:28674537

  7. [Analysis of effects of salt stress on absorption and accumulation of mineral elements in Elymus spp. using atomic absorption spectrophotometer].

    PubMed

    Jia, Ya-xiong; Sun, Lei; He, Feng; Wan, Li-qiang; Yuan, Qing-hua; Li, Xiang-lin

    2008-12-01

    Salinization contributes significantly to soil degradation and the growth and survival of plants. A high level of salts imposes both ionic and osmotic stresses on plants, resulting in an excessive accumulation of sodium (Na) in plant tissues. Na toxicity disrupts the uptake of soil nutrients. Plant uptake and absorption of macro-elements under salt stress have been studied in plants, but there is little literature addressing the effect of salt stress on plant accumulation and absorption of micro-elements. Species in Elymus genus are among the most important forage plants on high-salinity soils in China An experiment was conducted to study the effect of salt stress on accumulation and absorption of both macro- and micro-elements by wild plants of Elymus genus. Plant samples taken from two populations with different salt tolerance were tested and the level of 4 macro-elements, namely Na, K, Ca and Mg, and 4 micro-elements, namely Cu, Fe, Mn, Zn was determined using atomic absorption spectrophotometer. The relationship between the selection of elements in the process of absorption and accumulation and salt tolerance was also analyzed. The results showed that the level of Na in root and leaf tissues increased with increasing salt stress. The level of Na in leaf tissue of plants with high salt tolerance (HS) was significantly higher than that in plants with low salt tolerance (P<0.05). The level of K and Ca decreased in response to increasing salt stress, while that in HS was higher than in LS. The level of Fe and Zn in the tissues of both roots and leaves increased. No significant difference was detected between HS and LS samples in the level of Cu in root tissues, while that of Cu in leaf tissue of both samples increased. The level of Mn decreased with increasing salt stress, but was higher in HS than in LS. Fe and Zn in roots and leaves of HS were lower than in those of LS.

  8. Screening for new accumulator plants in Andes Range mines

    NASA Astrophysics Data System (ADS)

    Bech, Jaume; Roca, Núria

    2016-04-01

    Toxic metal pollution of waters and soils is a major environmental problem, and most conventional remediation approaches do not provide acceptable solutions. The use of plants or plant products to restore or stabilize contaminated sites, collectively known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate, store, or degrade organic and inorganic substances. Although not a new concept, phytoremediation is currently being re-examined as an environmentally friendly, cost-effective means of reducing metal contaminated soil. Plants growing on naturally metal-enriched soils are of particular interest in this regard, since they are genetically tolerant to high metal concentrations and have an excellent adaptation to this multi-stress environment. Processes include using plants that tolerate and accumulate metals at high levels (phytoextraction) and using plants that can grow under conditions that are toxic to other plants while preventing, for example, soil erosion (phytostabilization). Soil and plant samples were taken at polymetallic mines in Peru, Ecuador and Chile. It is suggested that Plantago orbignyana Steinheil is a Pb hyperaccumulator. Moreover, unusually elevated concentrations of Pb (over 1000 mg kg-1) and Translocation Factor (TF) greater than one were also detected in shoots of 6 different plants species (Ageratina sp., Achirodine alata, Cortaderia apalothica, Epilobium denticulatum, Taraxacum officinalis and Trifolium repens) of a Caroline mine in Perú. Among the grass species (Poaceae), the highest shoot As concentration were found in Paspalum sp. (>1000 μg g-1) and Eriochola ramose (460 μg g-1) from the Cu mine in Peru and in Holcus lanatus and Pennisetum clandestinum (>200 μg g-1) from the silver mine in Ecuador. The shoot accumulation of Zn was highest in Baccharis amdatensis (>1900 μg g-1) and in Rumex crispus (1300 μg g-1) from the Ag mine in Ecuador (Bech et al., 2002). Paspalum racemosum also

  9. HIV populations are large and accumulate high genetic diversity in a nonlinear fashion.

    PubMed

    Maldarelli, Frank; Kearney, Mary; Palmer, Sarah; Stephens, Robert; Mican, JoAnn; Polis, Michael A; Davey, Richard T; Kovacs, Joseph; Shao, Wei; Rock-Kress, Diane; Metcalf, Julia A; Rehm, Catherine; Greer, Sarah E; Lucey, Daniel L; Danley, Kristen; Alter, Harvey; Mellors, John W; Coffin, John M

    2013-09-01

    HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.

  10. Accumulation, metabolism, and food-chain transfer of chlorinated and brominated contaminants in subadult white whales (Delphinapterus leucas) and narwhals (Monodon monoceros) from Svalbard, Norway.

    PubMed

    Wolkers, H; Lydersen, C; Kovacs, K M; Burkow, I; van Bavel, B

    2006-01-01

    The concentrations and patterns of polychlorinated biphenyls (PCBs), chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs) were studied in white whales (Delphinapterus leucas) and narwhals (Monodon monoceros) from Svalbard, Norway. In addition, their main food items were included in the study. In the whales, a broad range of pollutants was found in relatively high concentrations. PCBs and pesticides were approximately 3000 and 8000 ng/g lipid, respectively, for white whales and three times higher for narwhals. PBDEs 47 were approximately 70 ng/g lipid for white whales and 170 ng/g lipid for narwhals. Compared with other marine mammals from the same area, contaminant levels are among the highest levels ever measured. These high levels are likely in part because of a decreased capacity to metabolize contaminants. Metabolic indices indicated that most compounds accumulate to the same degree in white whales and narwhals, but for some toxaphenes and chlordanes, narwhals might have a decreased metabolism and consequently a higher accumulation. The three-times-higher contaminant levels in blubber of narwhals was further explained by substantially higher contaminant levels in their more benthic diet. The high levels and broad pattern of accumulating pollutants make white whales and narwhals excellent indicators for a wide range of contaminants in the Arctic.

  11. Metal(loid) accumulation in aquatic plants of a mining area: Potential for water quality biomonitoring and biogeochemical prospecting.

    PubMed

    Favas, Paulo J C; Pratas, João; Rodrigues, Nelson; D'Souza, Rohan; Varun, Mayank; Paul, Manoj S

    2018-03-01

    Aquatic bryophytes can accumulate extremely high levels of chemical elements because of their unique morphology and physiology which is markedly different from vascular plants. Four aquatic mosses-Fontinalis squamosa, Brachythecium rivulare, Platyhypnidium riparioides, Thamnobryum alopecurum-and a freshwater red alga Lemanea fluviatilis along with water samples from the streams of Góis mine region in Central Portugal were analyzed for 46 elements. Despite being below detection levels in the water samples, the elements Zr, V, Cr, Mo, Ru, Os, Rh, Ir, Pt, Ag, Ge and Bi were obtained in the plant samples. The moss T. alopecurum had the highest mean concentrations of 19 elements followed by B. rivulare (15 elements). Maximum accumulation of Rb, Ta and Au, however, was seen in the alga L. fluviatilis. Bioconcentration factors > 10 6 were obtained for a few metals. The investigation confirms that aquatic bryophytes can be suitable for water quality biomonitoring and biogeochemical prospecting in fresh water bodies owing to their high accumulative capacity of multi-elements from their aquatic ambient. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Critical tissue residue approach linking accumulated metals in aquatic insects to population and community-level effects

    USGS Publications Warehouse

    Schmidt, Travis S.; Clements, William H.; Zuellig, Robert E.; Mitchell, Katharine A.; Church, Stan E.; Wanty, Richard B.; San Juan, Carma A.; Adams, Monique; Lamothe, Paul J.

    2011-01-01

    Whole body Zn concentrations in individuals (n = 825) from three aquatic insect taxa (mayflies Rhithrogena spp. and Drunella spp. and the caddisfly Arctopsyche grandis) were used to predict effects on populations and communities (n = 149 samples). Both mayflies accumulated significantly more Zn than the caddisfly. The presence/absence of Drunella spp. most reliably distinguished sites with low and high Zn concentrations; however, population densities of mayflies were more sensitive to increases in accumulated Zn. Critical tissue residues (634 (mu or u)g/g Zn for Drunella spp. and 267 (mu or u)g/g Zn for Rhithrogena spp.) caused a 20% reduction in maximum (90th quantile) mayfly densities. These critical tissue residues were associated with exposure to 7.0 and 3.9 (mu or u)g/L dissolved Zn for Drunella spp. and Rhithrogena spp., respectively. A threshold in a measure of taxonomic completeness (observed/expected) was observed at 5.4 (mu or u)g/L dissolved Zn. Dissolved Zn concentrations associated with critical tissue residues in mayflies were also associated with adverse effects in the aquatic community as a whole. These effects on populations and communities occurred at Zn concentrations below the U.S. EPA hardness-adjusted continuous chronic criterion.

  13. High potassium level

    MedlinePlus

    ... level is very high, or if you have danger signs, such as changes in an ECG . Emergency ... Seifter JL. Potassium disorders. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  14. Organochlorine pesticides accumulation and breast cancer: A hospital-based case-control study.

    PubMed

    He, Ting-Ting; Zuo, An-Jun; Wang, Ji-Gang; Zhao, Peng

    2017-05-01

    The aim of this study is to detect the accumulation status of organochlorine pesticides in breast cancer patients and to explore the relationship between organochlorine pesticides contamination and breast cancer development. We conducted a hospital-based case-control study in 56 patients with breast cancer and 46 patients with benign breast disease. We detected the accumulation level of several organochlorine pesticides products (β-hexachlorocyclohexane, γ-hexachlorocyclohexane, polychlorinated biphenyls-28, polychlorinated biphenyls-52, pentachlorothioanisole, and pp'-dichlorodiphenyldichloroethane) in breast adipose tissues of all 102 patients using gas chromatography. Thereafter, we examined the expression status of estrogen receptor, progesterone receptor, human epidermal growth factor receptor-2 (HER2), and Ki-67 in 56 breast cancer cases by immunohistochemistry. In addition, we analyzed the risk of breast cancer in those patients with organochlorine pesticides contamination using a logistic regression model. Our data showed that breast cancer patients suffered high accumulation levels of pp'-dichlorodiphenyldichloroethane and polychlorinated biphenyls-52. However, the concentrations of pp'-dichlorodiphenyldichloroethane and polychlorinated biphenyls-52 were not related to clinicopathologic parameters of breast cancer. Further logistic regression analysis showed polychlorinated biphenyls-52 and pp'-dichlorodiphenyldichloroethane were risk factors for breast cancer. Our results provide new evidence on etiology of breast cancer.

  15. Blood orange juice inhibits fat accumulation in mice.

    PubMed

    Titta, L; Trinei, M; Stendardo, M; Berniakovich, I; Petroni, K; Tonelli, C; Riso, P; Porrini, M; Minucci, S; Pelicci, P G; Rapisarda, P; Reforgiato Recupero, G; Giorgio, M

    2010-03-01

    To analyze the effect of the juice obtained from two varieties of sweet orange (Citrus sinensis L. Osbeck), Moro (a blood orange) and Navelina (a blond orange), on fat accumulation in mice fed a standard or a high-fat diet (HFD). Obesity was induced in male C57/Bl6 mice by feeding a HFD. Moro and Navelina juices were provided instead of water. The effect of an anthocyanin-enriched extract from Moro oranges or purified cyanidin-3-glucoside (C3G) was also analyzed. Body weight and food intake were measured regularly over a 12-week period. The adipose pads were weighted and analyzed histologically; total RNA was also isolated for microarray analysis. Dietary supplementation of Moro juice, but not Navelina juice significantly reduced body weight gain and fat accumulation regardless of the increased energy intake because of sugar content. Furthermore, mice drinking Moro juice were resistant to HFD-induced obesity with no alterations in food intake. Only the anthocyanin extract, but not the purified C3G, slightly affected fat accumulation. High-throughput gene expression analysis of fat tissues confirmed that Moro juice could entirely rescue the high fat-induced transcriptional reprogramming. Moro juice anti-obesity effect on fat accumulation cannot be explained only by its anthocyanin content. Our findings suggest that multiple components present in the Moro orange juice might act synergistically to inhibit fat accumulation.

  16. IMPACT OF PARTICLE AGGLOMERATION ON ACCUMULATION RATES IN THE GLASS DISCHARGE RISER OF HLW MELTER

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matyas, Josef; Jansik, Danielle P.; Owen, Antionette T.

    2013-08-05

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with X-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, andmore » on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185±155 µm, and produced >3 mm thick layer after 120 h at 850 °C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.« less

  17. Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kruger, A. A.; Rodriguez, C. A.; Matyas, J.

    2012-11-12

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, andmore » on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185+-155 {mu}m, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.« less

  18. Accumulation of Poly(3-hydroxybutyrate) Helps Bacterial Cells to Survive Freezing

    PubMed Central

    Krzyzanek, Vladislav; Mravec, Filip; Hrubanova, Kamila; Samek, Ota; Kucera, Dan; Benesova, Pavla; Marova, Ivana

    2016-01-01

    Accumulation of polyhydroxybutyrate (PHB) seems to be a common metabolic strategy adopted by many bacteria to cope with cold environments. This work aimed at evaluating and understanding the cryoprotective effect of PHB. At first a monomer of PHB, 3-hydroxybutyrate, was identified as a potent cryoprotectant capable of protecting model enzyme (lipase), yeast (Saccharomyces cerevisiae) and bacterial cells (Cupriavidus necator) against the adverse effects of freezing-thawing cycles. Further, the viability of the frozen–thawed PHB accumulating strain of C. necator was compared to that of the PHB non-accumulating mutant. The presence of PHB granules in cells was revealed to be a significant advantage during freezing. This might be attributed to the higher intracellular level of 3-hydroxybutyrate in PHB accumulating cells (due to the action of parallel PHB synthesis and degradation, the so-called PHB cycle), but the cryoprotective effect of PHB granules seems to be more complex. Since intracellular PHB granules retain highly flexible properties even at extremely low temperatures (observed by cryo-SEM), it can be expected that PHB granules protect cells against injury from extracellular ice. Finally, thermal analysis indicates that PHB-containing cells exhibit a higher rate of transmembrane water transport, which protects cells against the formation of intracellular ice which usually has fatal consequences. PMID:27315285

  19. Evaluating blood and excrement as bioindicators for metal accumulation in birds.

    PubMed

    Berglund, Åsa M M

    2018-02-01

    Birds are widely used to assess metal contamination in the environment and there are different approaches to determine the exposure level in individuals, some being destructive (collection of soft tissues) and some non-destructive (blood, feathers and excrement). The use of blood to detect internal concentrations of metals is an acknowledged method, but to what extent blood can predict the concentrations in soft tissues has been less well evaluated in wild terrestrial birds. The same is true for excrements. This study compares the non-destructive methods using blood and excrement with liver sampling, with respect to exposure and accumulation of the elements arsenic, cadmium, copper, lead and zinc in nestling pied flycatchers (Ficedula hypoleuca). Blood, liver and excrement reflected the environmental exposure of non-essential elements and were independent of nestling sex. There were asymptotic relationships between the concentration of arsenic, cadmium and lead in liver and blood, excrement and liver, and excrement and blood, but none for copper or zinc. Those relationships were generally stronger between liver and blood than between excrements and internal concentrations. Lead had the strongest associations for all matrixes. The conclusion is that blood is an appropriate tool to assess accumulation of arsenic, cadmium and especially lead, but that blood can underestimate the accumulation at highly contaminated sites. Excrement can also give an indication of metal accumulation, but may overestimate internal concentrations at high exposure, and individual variability makes direct comparisons between these matrices less appropriate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Iodide accumulation provides kelp with an inorganic antioxidant impacting atmospheric chemistry

    PubMed Central

    Küpper, Frithjof C.; Carpenter, Lucy J.; McFiggans, Gordon B.; Palmer, Carl J.; Waite, Tim J.; Boneberg, Eva-Maria; Woitsch, Sonja; Weiller, Markus; Abela, Rafael; Grolimund, Daniel; Potin, Philippe; Butler, Alison; Luther, George W.; Kroneck, Peter M. H.; Meyer-Klaucke, Wolfram; Feiters, Martin C.

    2008-01-01

    Brown algae of the Laminariales (kelps) are the strongest accumulators of iodine among living organisms. They represent a major pump in the global biogeochemical cycle of iodine and, in particular, the major source of iodocarbons in the coastal atmosphere. Nevertheless, the chemical state and biological significance of accumulated iodine have remained unknown to this date. Using x-ray absorption spectroscopy, we show that the accumulated form is iodide, which readily scavenges a variety of reactive oxygen species (ROS). We propose here that its biological role is that of an inorganic antioxidant, the first to be described in a living system. Upon oxidative stress, iodide is effluxed. On the thallus surface and in the apoplast, iodide detoxifies both aqueous oxidants and ozone, the latter resulting in the release of high levels of molecular iodine and the consequent formation of hygroscopic iodine oxides leading to particles, which are precursors to cloud condensation nuclei. In a complementary set of experiments using a heterologous system, iodide was found to effectively scavenge ROS in human blood cells. PMID:18458346

  1. Comparative biochemistry of betaine biosynthesis and accumulation in diverse dicot families

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCue, K.F.; Weretilnyk, E.A.; Bednarek, S.Y.

    1989-04-01

    Salt stress elicits betaine accumulation to high levels in species from several diverse dicot families (Chenopodiaceae, Amaranthaceae, Convolvulaceae, Solanaceae, and Asteraceae). FAM-MS studies with deuterated precursors showed that species from all these families synthesize betaine from choline. Enzyme assays and immunotitration data showed that all accumulating species contained betaine aldehyde dehydrogenase (BADH) enzyme activity recognized by antibodies raised against purified BADH isolated from Spinacia oleracea. Immunoblotting indicated that the BADH monomer was in all cases of Mr {approx} 63,000. The similarity of BADH in the different species is consistent with a single evolutionary origin for the betaine pathway. This wasmore » supported by the presence in immunoblots of a cross-reacting band at Mr {approx} 63,000 in Magnolia x Soulangiana, a primitive angiosperm.« less

  2. Modulation of cAMP levels by high fat diet and curcumin and regulatory effects on CD36/FAT scavenger receptor/fatty acids transporter gene expression

    USDA-ARS?s Scientific Manuscript database

    Curcumin, a polyphenol from turmeric (Curcuma longa), reduces inflammation, atherosclerosis, and obesity in several animal studies. In Ldlr-/- mice fed a high-fat diet (HFD), curcumin reduces plasma lipid levels, therefore contributing to a lower accumulation of lipids and to reduced expression of f...

  3. Abnormal troponin I levels in a thalassemia major patient with high ferritin concentration, permanent atrial fibrillation and without acute coronary syndrome.

    PubMed

    Patanè, Salvatore; Marte, Filippo

    2010-01-21

    Thalassemia is a congenital hemoglobinopathy leading to anemia because of impaired erythropoiesis and peripheral hemolysis. Thalassemia major patients are transfusion dependent and it results in iron accumulation. The heart is one of the major organs affected with iron overload and iron induced cardiac dysfunction (pump and conduction abnormalities) remains the number one cause of death among thalassemia major patients. It has been reported that a high ferritin concentration is related to high troponin levels in hemodialysis patients receiving more intravenous iron sucrose. Abnormal troponin I levels have also been reported without acute coronary syndrome. We present a case of abnormal troponin I levels in Thalassemia major patient with high ferritin concentration, permanent atrial fibrillation and without acute coronary syndrome. To our knowledge, this is the first report of abnormal troponin I levels in a Thalassemia major patient with high ferritin concentration and without acute coronary syndrome and also this case focuses attention on the importance of the correct evaluation of abnormal troponin I levels. Copyright (c) 2008 Elsevier Ireland Ltd. All rights reserved.

  4. Factors Influencing Biogenic Amines Accumulation in Dairy Products

    PubMed Central

    Linares, Daniel M.; del Río, Beatriz; Ladero, Victor; Martínez, Noelia; Fernández, María; Martín, María Cruz; Álvarez, Miguel A.

    2012-01-01

    Fermented foods are among the food products more often complained of having caused episodes of biogenic amines (BA) poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain potentially harmful levels of BA, specially tyramine, histamine, and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report all those elaboration and processing technological aspects affecting BA biosynthesis and accumulation in dairy foods. Improved knowledge of the factors involved in the synthesis and accumulation of BA should lead to a reduction in their incidence in milk products. Synthesis of BA is possible only when three conditions converge: (i) availability of the substrate amino acids; (ii) presence of microorganisms with the appropriate catabolic pathway activated; and (iii) environmental conditions favorable to the decarboxylation activity. These conditions depend on several factors such as milk treatment (pasteurization), use of starter cultures, NaCl concentration, time, and temperature of ripening and preservation, pH, temperature, or post-ripening technological processes, which will be discussed in this chapter. PMID:22783233

  5. Low-field and high-field magnetic resonance contrast imaging of magnetoferritin as a pathological model system of iron accumulation

    NASA Astrophysics Data System (ADS)

    Strbak, Oliver; Balejcikova, Lucia; Baciak, Ladislav; Kovac, Jozef; Masarova-Kozelova, Marta; Krafcik, Andrej; Dobrota, Dusan; Kopcansky, Peter

    2017-09-01

    Various pathological processes including neurodegenerative disorders are associated with the accumulation of iron, while it is believed that a precursor of iron accumulation is ferritin. Physiological ferritin is due to low relaxivity, which results in only weak detection by magnetic resonance imaging (MRI) techniques. On the other hand, pathological ferritin is associated with disrupted iron homeostasis and structural changes in the mineral core, and should increase the hypointensive artefacts in MRI. On the basis of recent findings in respect to the pathological ferritin structure, we prepared the magnetoferritin particles as a possible pathological ferritin model system. The particles were characterised with dynamic light scattering, as well as with superconducting quantum interference device measurements. With the help of low-field (0.2 T) and high-field (4.7 T) MRI standard T 2-weighted protocols we found that it is possible to clearly distinguish between native ferritin as a physiological model system, and magnetoferritin as a pathological model system. Surprisingly, the T 2-weighted short TI inversion recovery protocol at low-field system showed the optimum contrast differentiation. Such findings are highly promising for exploiting the use of iron accumulation as a noninvasive diagnostics tool of pathological processes, where the magnetoferritin particles could be utilised as MRI iron quantification calibration samples.

  6. High pressure liquid level monitor

    DOEpatents

    Bean, Vern E.; Long, Frederick G.

    1984-01-01

    A liquid level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  7. Rice koji reduced body weight gain, fat accumulation, and blood glucose level in high-fat diet-induced obese mice

    PubMed Central

    Yoshizaki, Yumiko; Kawasaki, Chihiro; Cheng, Kai-Chun; Ushikai, Miharu; Amitani, Haruka; Asakawa, Akihiro; Okutsu, Kayu; Sameshima, Yoshihiro; Takamine, Kazunori

    2014-01-01

    Rice koji is considered a readily accessible functional food that may have health-promoting effects. We investigated whether white, yellow, and red koji have the anti-obesity effect in C57BL/6J mice fed a high-fat diet (HFD), which is a model for obesity. Mice were fed HFD containing 10% (w/w) of rice koji powder or steamed rice for 4 weeks. Weight gain, epididymal white adipose tissue, and total adipose tissue weight were significantly lower in all rice koji groups than in the HFD-rice group after 4 weeks. Feed efficiency was significantly reduced in the yellow koji group. Blood glucose levels were significantly lower in the white and red koji groups with HOMA-R and leptin levels being reduced in the white koji group. White and red koji increased glucose uptake and GLUT4 protein expression in L6 myotube cells. These results showed that all rice koji have the anti-obesity or anti-diabetes effects although the mechanisms may differ depending on the type of rice koji consumed. PMID:25237599

  8. Rice koji reduced body weight gain, fat accumulation, and blood glucose level in high-fat diet-induced obese mice.

    PubMed

    Yoshizaki, Yumiko; Kawasaki, Chihiro; Cheng, Kai-Chun; Ushikai, Miharu; Amitani, Haruka; Asakawa, Akihiro; Okutsu, Kayu; Sameshima, Yoshihiro; Takamine, Kazunori; Inui, Akio

    2014-01-01

    Rice koji is considered a readily accessible functional food that may have health-promoting effects. We investigated whether white, yellow, and red koji have the anti-obesity effect in C57BL/6J mice fed a high-fat diet (HFD), which is a model for obesity. Mice were fed HFD containing 10% (w/w) of rice koji powder or steamed rice for 4 weeks. Weight gain, epididymal white adipose tissue, and total adipose tissue weight were significantly lower in all rice koji groups than in the HFD-rice group after 4 weeks. Feed efficiency was significantly reduced in the yellow koji group. Blood glucose levels were significantly lower in the white and red koji groups with HOMA-R and leptin levels being reduced in the white koji group. White and red koji increased glucose uptake and GLUT4 protein expression in L6 myotube cells. These results showed that all rice koji have the anti-obesity or anti-diabetes effects although the mechanisms may differ depending on the type of rice koji consumed.

  9. High levels of histones promote whole-genome-duplications and trigger a Swe1WEE1-dependent phosphorylation of Cdc28CDK1

    PubMed Central

    Peñate, Xenia; Sanmartín Olmo, Trinidad; Jourquin, Frederic; Muñoz Centeno, Maria Cruz; Mendoza, Manuel; Simon, Marie-Noelle; Chavez, Sebastian

    2018-01-01

    Whole-genome duplications (WGDs) have played a central role in the evolution of genomes and constitute an important source of genome instability in cancer. Here, we show in Saccharomyces cerevisiae that abnormal accumulations of histones are sufficient to induce WGDs. Our results link these WGDs to a reduced incorporation of the histone variant H2A.Z to chromatin. Moreover, we show that high levels of histones promote Swe1WEE1 stabilisation thereby triggering the phosphorylation and inhibition of Cdc28CDK1 through a mechanism different of the canonical DNA damage response. Our results link high levels of histones to a specific type of genome instability that is quite frequently observed in cancer and uncovers a new mechanism that might be able to respond to high levels of histones. PMID:29580382

  10. Ethylene Induced a High Accumulation of Dietary Isoflavones and Expression of Isoflavonoid Biosynthetic Genes in Soybean (Glycine max) Leaves.

    PubMed

    Yuk, Heung Joo; Song, Yeong Hun; Curtis-Long, Marcus J; Kim, Dae Wook; Woo, Su Gyeong; Lee, Yong Bok; Uddin, Zia; Kim, Cha Young; Park, Ki Hun

    2016-10-05

    Dietary isoflavones, daidzein and genistein are of huge interest in the nutraceutical field due to their practical application to postmenopause complications. This study is the first report an efficient method to prepare isoflavone rich soybean leaves (soyleaves) which is an edible food stuff in Asian countries. The preharvest treatment of ethylene highly stimulated the level of isoflavone in soyleaves. Annotation and quantification of metabolites were determined by UPLC-Q-TOF-MS and HPLC. Phenolic metabolites of soyleaves are mostly kaempferol glycosides, but not dietary isoflavones. The accumulated isoflavones by ethylene treatment were determined to be daidzin 1, genistin 2, malonyldaidzin 3 and malonylgenistin 4, which were easily hydrolyzed to daidzein and genistein by β-glucosidase. Total content of dietary isoflavones was increased up to 13854 μg/g. The most suitable condition was estimated to be 250 μg/g ethylene or 200 μg/g ethephon (ethylene donor) treatment at the R3 growth stage. The ratio of daidzein and genistein glycosides was approximately 5 to 3. The accumulated isoflavonoid biosynthesis pathway genes were identified within the transcriptome of soyleaves tissues at 1 day after treatment of ethephon. The quantitative RT-PCR analysis of these genes indicated significantly higher expression of CHS, CHI, IFS, HID, IF7GT, and IF7MaT compared to control leaves. These findings suggest that ethylene activates a set of structural genes involved in isoflavonoid biosynthesis, thereby leading to enhanced production of isoflavones in soybean plants.

  11. Chromium accumulation potential of Zea mays grown under four different fertilizers.

    PubMed

    Dheeba, B; Sampathkumar, P; Kannan, K

    2014-12-01

    Chromium (Cr) contamination in soil is a growing concern in sustainable agriculture production and food safety. We performed pot experiment with chromium (30 mg/soil) to assess the accumulation potential of Zea mays and study the influence of four fertilizers, viz. Farm Yard Manure (FYM), NPK, Panchakavya (PK) and Vermicompost (VC) with respect to Cr accumulation. The oxidative stress and pigment (chlorophyll) levels were also examined. The results showed increased accumulation of chromium in both shoots and roots of Zea mays under FYM and NPK supply, and reduced with PK and VC. While the protein and pigment contents decreased in Cr treated plants, the fertilizers substantiated the loss to overcome the stress. Similarly, accumulation of Cr increased the levels of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) indicating the enhanced damage control activity. However, these levels were relatively low in plants supplemented with fertilizers. Our results confirm that the maize can play an effective role in bioremediation of soils polluted with chromium, particularly in supplementation with fertilizers such as farm yard manure and NPK.

  12. Molecular analysis of ureide accumulation under drought stress in Phaseolus vulgaris L.

    PubMed

    Alamillo, Josefa M; Díaz-Leal, Juan Luís; Sánchez-Moran, Ma Victoria; Pineda, Manuel

    2010-11-01

    Under water deficit, ureidic legumes accumulate ureides in plant tissues, and this accumulation has been correlated with the inhibition of nitrogen fixation. In this work we used a molecular approach to characterize ureide accumulation under drought stress in Phaseolus vulgaris. Accumulation of ureides, mainly allantoate, was found in roots, shoots and leaves, but only a limited transient increase was observed in nodules from drought-stressed plants. We show that ureide accumulation is regulated at the transcriptional level mainly through induction of allantoinase (ALN), whereas allantoate amidohydrolase (AAH), involved in allantoate degradation, was slightly reduced, indicating that inhibition of this enzyme, key in ureide breakdown in aerial tissues, is not the main cause of allantoate accumulation. Expression of the ureide metabolism genes analysed in this study was induced by abscisic acid (ABA), suggesting the involvement of this plant hormone in ureide accumulation. Moreover, we observed that increases of ureide levels in P. vulgaris drought-stressed tissues were similar in non-nodulated, nitrate-fed plants, and in plants cultured under nitrogen-fixation conditions. Our results indicate that ureide accumulation in response to water deficit is independent from de novo synthesis of ureides in nodules, and therefore uncoupled from nitrogen fixation. © 2010 Blackwell Publishing Ltd.

  13. Hepatic free cholesterol accumulates in obese, diabetic mice and causes nonalcoholic steatohepatitis.

    PubMed

    Van Rooyen, Derrick M; Larter, Claire Z; Haigh, W Geoffrey; Yeh, Matthew M; Ioannou, George; Kuver, Rahul; Lee, Sum P; Teoh, Narci C; Farrell, Geoffrey C

    2011-10-01

    Type 2 diabetes and nonalcoholic steatohepatitis (NASH) are associated with insulin resistance and disordered cholesterol homeostasis. We investigated the basis for hepatic cholesterol accumulation with insulin resistance and its relevance to the pathogenesis of NASH. Alms1 mutant (foz/foz) and wild-type NOD.B10 mice were fed high-fat diets that contained varying percentages of cholesterol; hepatic lipid pools and pathways of cholesterol turnover were determined. Hepatocytes were exposed to insulin concentrations that circulate in diabetic foz/foz mice. Hepatic cholesterol accumulation was attributed to up-regulation of low-density lipoprotein receptor via activation of sterol regulatory element binding protein 2 (SREBP-2), reduced biotransformation to bile acids, and suppression of canalicular pathways for cholesterol and bile acid excretion in bile. Exposing primary hepatocytes to concentrations of insulin that circulate in diabetic Alms1 mice replicated the increases in SREBP-2 and low-density lipoprotein receptor and suppression of bile salt export pump. Removing cholesterol from diet prevented hepatic accumulation of free cholesterol and NASH; increasing dietary cholesterol levels exacerbated hepatic accumulation of free cholesterol, hepatocyte injury or apoptosis, macrophage recruitment, and liver fibrosis. In obese, diabetic mice, hyperinsulinemia alters nuclear transcriptional regulators of cholesterol homeostasis, leading to hepatic accumulation of free cholesterol; the resulting cytotoxicity mediates transition of steatosis to NASH. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. Highly anomalous accumulation rates of C and N recorded by a relic, free-floating peatland in Central Italy

    PubMed Central

    Zaccone, Claudio; Lobianco, Daniela; Shotyk, William; Ciavatta, Claudio; Appleby, Peter G.; Brugiapaglia, Elisabetta; Casella, Laura; Miano, Teodoro M.; D’Orazio, Valeria

    2017-01-01

    Floating islands mysteriously moving around on lakes were described by several Latin authors almost two millennia ago. These fascinating ecosystems, known as free-floating mires, have been extensively investigated from ecological, hydrological and management points of view, but there have been no detailed studies of their rates of accumulation of organic matter (OM), organic carbon (OC) and total nitrogen (TN). We have collected a peat core 4 m long from the free-floating island of Posta Fibreno, a relic mire in Central Italy. This is the thickest accumulation of peat ever found in a free-floating mire, yet it has formed during the past seven centuries and represents the greatest accumulation rates, at both decadal and centennial timescale, of OM (0.63 vs. 0.37 kg/m2/yr), OC (0.28 vs. 0.18 kg/m2/yr) and TN (3.7 vs. 6.1 g/m2/yr) ever reported for coeval peatlands. The anomalously high accretion rates, obtained using 14C age dating, were confirmed using 210Pb and 137Cs: these show that the top 2 m of Sphagnum-peat has accumulated in only ~100 years. As an environmental archive, Posta Fibreno offers a temporal resolution which is 10x greater than any terrestrial peat bog, and promises to provide new insight into environmental changes occurring during the Anthropocene. PMID:28230066

  15. Episodic strain accumulation in southern california.

    PubMed

    Thatcher, W

    1976-11-12

    Reexamination of horizontal geodetic data in the region of recently discovered aseismic uplift has demonstrated that equally unusual horizontal crustal deformation accompanied the development of the uplift. During this time interval compressive strains were oriented roughly normal to the San Andreas fault, suggesting that the uplift produced little shear strain accumulation across this fault. On the other hand, the orientation of the anomalous shear straining is consistent with strain accumulation across northdipping range-front thrusts like the San Fernando fault. Accordingly, the horizontal and vertical crustal deformation disclosed by geodetic observation is interpreted as a short epoch of rapid strain accumulation on these frontal faults. If this interpretation is correct, thrust-type earthquakes will eventually release the accumulated strains, but the geodetic data examined here cannot be used to estimate when these events might occur. However, observation of an unusual sequence of tilts prior to 1971 on a level line lying to the north of the magnitude 6.4 San Fernando earthquake offers some promise for precursor monitoring. The data are adequately explained by a simple model of up-dip aseismic slip propagation toward the 1971 epicentral region. These observations and the simple model that accounts for them suggest a conceptually straightforward monitoring scheme to search for similar uplift and tilt precursors within the uplifted region. Such premonitory effects could be detected by a combination of frequenlty repeated short (30 to 70 km in length) level line measurements, precise gravity traverses, and continuously recording gravimeters sited to the north of the active frontal thrust faults. Once identified, such precursors could be closely followed in space and time, and might then provide effective warnings of impending potentially destructive earth-quakes.

  16. Sunlight Modulates Fruit Metabolic Profile and Shapes the Spatial Pattern of Compound Accumulation within the Grape Cluster.

    PubMed

    Reshef, Noam; Walbaum, Natasha; Agam, Nurit; Fait, Aaron

    2017-01-01

    Vineyards are characterized by their large spatial variability of solar irradiance (SI) and temperature, known to effectively modulate grape metabolism. To explore the role of sunlight in shaping fruit composition and cluster uniformity, we studied the spatial pattern of incoming irradiance, fruit temperature and metabolic profile within individual grape clusters under three levels of sunlight exposure. The experiment was conducted in a vineyard of Cabernet Sauvignon cv. located in the Negev Highlands, Israel, where excess SI and midday temperatures are known to degrade grape quality. Filtering SI lowered the surface temperature of exposed fruits and increased the uniformity of irradiance and temperature in the cluster zone. SI affected the overall levels and patterns of accumulation of sugars, organic acids, amino acids and phenylpropanoids, across the grape cluster. Increased exposure to sunlight was associated with lower accumulation levels of malate, aspartate, and maleate but with higher levels of valine, leucine, and serine, in addition to the stress-related proline and GABA. Flavan-3-ols metabolites showed a negative response to SI, whereas flavonols were highly induced. The overall levels of anthocyanins decreased with increased sunlight exposure; however, a hierarchical cluster analysis revealed that the members of this family were grouped into three distinct accumulation patterns, with malvidin anthocyanins and cyanidin-glucoside showing contrasting trends. The flavonol-glucosides, quercetin and kaempferol, exhibited a logarithmic response to SI, leading to improved cluster uniformity under high-light conditions. Comparing the within-cluster variability of metabolite accumulation highlighted the stability of sugars, flavan-3-ols, and cinnamic acid metabolites to SI, in contrast to the plasticity of flavonols. A correlation-based network analysis revealed that extended exposure to SI modified metabolic coordination, increasing the number of negative

  17. Sunlight Modulates Fruit Metabolic Profile and Shapes the Spatial Pattern of Compound Accumulation within the Grape Cluster

    PubMed Central

    Reshef, Noam; Walbaum, Natasha; Agam, Nurit; Fait, Aaron

    2017-01-01

    Vineyards are characterized by their large spatial variability of solar irradiance (SI) and temperature, known to effectively modulate grape metabolism. To explore the role of sunlight in shaping fruit composition and cluster uniformity, we studied the spatial pattern of incoming irradiance, fruit temperature and metabolic profile within individual grape clusters under three levels of sunlight exposure. The experiment was conducted in a vineyard of Cabernet Sauvignon cv. located in the Negev Highlands, Israel, where excess SI and midday temperatures are known to degrade grape quality. Filtering SI lowered the surface temperature of exposed fruits and increased the uniformity of irradiance and temperature in the cluster zone. SI affected the overall levels and patterns of accumulation of sugars, organic acids, amino acids and phenylpropanoids, across the grape cluster. Increased exposure to sunlight was associated with lower accumulation levels of malate, aspartate, and maleate but with higher levels of valine, leucine, and serine, in addition to the stress-related proline and GABA. Flavan-3-ols metabolites showed a negative response to SI, whereas flavonols were highly induced. The overall levels of anthocyanins decreased with increased sunlight exposure; however, a hierarchical cluster analysis revealed that the members of this family were grouped into three distinct accumulation patterns, with malvidin anthocyanins and cyanidin-glucoside showing contrasting trends. The flavonol-glucosides, quercetin and kaempferol, exhibited a logarithmic response to SI, leading to improved cluster uniformity under high-light conditions. Comparing the within-cluster variability of metabolite accumulation highlighted the stability of sugars, flavan-3-ols, and cinnamic acid metabolites to SI, in contrast to the plasticity of flavonols. A correlation-based network analysis revealed that extended exposure to SI modified metabolic coordination, increasing the number of negative

  18. Comparative transcriptome analysis to investigate the high starch accumulation of duckweed (Landoltia punctata) under nutrient starvation.

    PubMed

    Tao, Xiang; Fang, Yang; Xiao, Yao; Jin, Yan-Ling; Ma, Xin-Rong; Zhao, Yun; He, Kai-Ze; Zhao, Hai; Wang, Hai-Yan

    2013-05-08

    Duckweed can thrive on anthropogenic wastewater and produce tremendous biomass production. Due to its relatively high starch and low lignin percentage, duckweed is a good candidate for bioethanol fermentation. Previous studies have observed that water devoid of nutrients is good for starch accumulation, but its molecular mechanism remains unrevealed. This study globally analyzed the response to nutrient starvation in order to investigate the starch accumulation in duckweed (Landoltia punctata). L. punctata was transferred from nutrient-rich solution to distilled water and sampled at different time points. Physiological measurements demonstrated that the activity of ADP-glucose pyrophosphorylase, the key enzyme of starch synthesis, as well as the starch percentage in duckweed, increased continuously under nutrient starvation. Samples collected at 0 h, 2 h and 24 h time points respectively were used for comparative gene expression analysis using RNA-Seq. A comprehensive transcriptome, comprising of 74,797 contigs, was constructed by a de novo assembly of the RNA-Seq reads. Gene expression profiling results showed that the expression of some transcripts encoding key enzymes involved in starch biosynthesis was up-regulated, while the expression of transcripts encoding enzymes involved in starch consumption were down-regulated, the expression of some photosynthesis-related transcripts were down-regulated during the first 24 h, and the expression of some transporter transcripts were up-regulated within the first 2 h. Very interestingly, most transcripts encoding key enzymes involved in flavonoid biosynthesis were highly expressed regardless of starvation, while transcripts encoding laccase, the last rate-limiting enzyme of lignifications, exhibited very low expression abundance in all three samples. Our study provides a comprehensive expression profiling of L. punctata under nutrient starvation, which indicates that nutrient starvation down-regulated the global metabolic

  19. Comparative transcriptome analysis to investigate the high starch accumulation of duckweed (Landoltia punctata) under nutrient starvation

    PubMed Central

    2013-01-01

    Background Duckweed can thrive on anthropogenic wastewater and produce tremendous biomass production. Due to its relatively high starch and low lignin percentage, duckweed is a good candidate for bioethanol fermentation. Previous studies have observed that water devoid of nutrients is good for starch accumulation, but its molecular mechanism remains unrevealed. Results This study globally analyzed the response to nutrient starvation in order to investigate the starch accumulation in duckweed (Landoltia punctata). L. punctata was transferred from nutrient-rich solution to distilled water and sampled at different time points. Physiological measurements demonstrated that the activity of ADP-glucose pyrophosphorylase, the key enzyme of starch synthesis, as well as the starch percentage in duckweed, increased continuously under nutrient starvation. Samples collected at 0 h, 2 h and 24 h time points respectively were used for comparative gene expression analysis using RNA-Seq. A comprehensive transcriptome, comprising of 74,797 contigs, was constructed by a de novo assembly of the RNA-Seq reads. Gene expression profiling results showed that the expression of some transcripts encoding key enzymes involved in starch biosynthesis was up-regulated, while the expression of transcripts encoding enzymes involved in starch consumption were down-regulated, the expression of some photosynthesis-related transcripts were down-regulated during the first 24 h, and the expression of some transporter transcripts were up-regulated within the first 2 h. Very interestingly, most transcripts encoding key enzymes involved in flavonoid biosynthesis were highly expressed regardless of starvation, while transcripts encoding laccase, the last rate-limiting enzyme of lignifications, exhibited very low expression abundance in all three samples. Conclusion Our study provides a comprehensive expression profiling of L. punctata under nutrient starvation, which indicates that nutrient starvation down

  20. CKA2 functions in H2O2-induced apoptosis and high-temperature stress tolerance by regulating NO accumulation in yeast.

    PubMed

    Liu, Wen-Cheng; Yuan, Hong-Mei; Li, Yun-Hui; Lu, Ying-Tang

    2015-09-01

    Nitric oxide (NO) plays key roles in yeast responses to various environmental factors, such as H2O2 and high temperature. However, the gene encoding NO synthase (NOS) in yeast has not yet been identified, and the mechanism underlying the regulation of NOS-like activity is poorly understood. Here, we report on the involvement of CKA2 in H2O2-induced yeast apoptosis and yeast high-temperature stress tolerance. Our results showed that although Δcka2 mutant had reduced NO accumulation with decreased apoptosis after H2O2 exposure, treatment with a NO donor, sodium nitroprusside, resulted in similar survival rate of Δcka2 mutant compared to that of wild-type yeast when subjected to H2O2 stress. This finding occurred because H2O2-enhanced NOS-like activity in wild-type yeast was significantly repressed in Δcka2. Our additional experiments indicated that both high-temperature-enhanced NO accumulation and NOS-like activity were also suppressed in Δcka2, leading to the hypersensitivity of the mutant to high temperature in terms of changes in survival rate. Thus, our results showed that CKA2 functioned in H2O2-induced apoptosis and high-temperature stress tolerance by regulating NOS-like-dependent NO accumulation in yeast. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Risk Factors and Levels of Risk for High School Dropouts

    ERIC Educational Resources Information Center

    Suh, Suhyun; Suh, Jingyo

    2007-01-01

    The study in this article identifies three major risk categories of high school dropouts and evaluates the impact of possible prevention strategies. As students accumulate these risks, they became more likely to drop out and prevention programs become less effective. Additionally, it was found that factors influencing the decision to drop out vary…

  2. Association of Lipid Accumulation Product with Cardio-Metabolic Risk Factors in Postmenopausal Women.

    PubMed

    Namazi Shabestari, Alireza; Asadi, Mojgan; Jouyandeh, Zahra; Qorbani, Mostafa; Kelishadi, Roya

    2016-06-01

    The lipid accumulation product is a novel, safe and inexpensive index of central lipid over accumulation based on waist circumference and fasting concentration of circulating triglycerides. This study was designed to investigate the ability of lipid accumulation product to predict Cardio-metabolic risk factors in postmenopausal women. In this Cross-sectional study, 264 postmenopausal women by using convenience sampling method were selected from menopause clinic in Tehran. Cardio-metabolic risk factors were measured, and lipid accumulation product (waist-58×triglycerides [nmol/L]) was calculated. Optimal cut-off point of lipid accumulation product for predicting metabolic syndrome was estimated by ROC (Receiver-operating characteristic) curve analysis. Metabolic syndrome was diagnosed in 41.2% of subjects. Optimal cut-off point of lipid accumulation product for predicting metabolic syndrome was 47.63 (sensitivity:75%; specificity:77.9%). High lipid accumulation product increases risk of all Cardio-metabolic risk factors except overweight, high Total Cholesterol, high Low Density Lipoprotein Cholesterol and high Fasting Blood Sugar in postmenopausal women. Our findings show that lipid accumulation product is associated with metabolic syndrome and some Cardio-metabolic risk factors Also lipid accumulation product may have been a useful tool for predicting cardiovascular disease and metabolic syndrome risk in postmenopausal women.

  3. Kefir prevented excess fat accumulation in diet-induced obese mice.

    PubMed

    Choi, Jae-Woo; Kang, Hye Won; Lim, Won-Chul; Kim, Mi-Kyoung; Lee, In-Young; Cho, Hong-Yon

    2017-05-01

    Excessive body fat accumulation can result in obesity, which is a serious health concern. Kefir, a probiotic, has recently shown possible health benefits in fighting obesity. This study investigated the inhibitory effects of 0.1 and 0.2% kefir powder on fat accumulation in adipose and liver tissues of high-fat diet (HFD)-induced obese mice. Kefir reduced body weight and epididymal fat pad weight and decreased adipocyte diameters in HFD-induced obese mice. This was supported by decreased expression of genes related to adipogenesis and lipogenesis as well as reduced proinflammatory marker levels in epididymal fat. Along with reduced hepatic triacylglycerol concentrations and serum alanine transaminase and aspartate transaminase activities, genes related to lipogenesis and fatty acid oxidation were downregulated and upregulated, respectively, in liver tissue. Kefir also decreased serum triacylglycerol, total cholesterol, and low-density lipoprotein-cholesterol concentrations. Overall, kefir has the potential to prevent obesity.

  4. Algal dual-specificity tyrosine phosphorylation-regulated kinase, triacylglycerol accumulation regulator1, regulates accumulation of triacylglycerol in nitrogen or sulfur deficiency.

    PubMed

    Kajikawa, Masataka; Sawaragi, Yuri; Shinkawa, Haruka; Yamano, Takashi; Ando, Akira; Kato, Misako; Hirono, Masafumi; Sato, Naoki; Fukuzawa, Hideya

    2015-06-01

    Although microalgae accumulate triacylglycerol (TAG) and starch in response to nutrient-deficient conditions, the regulatory mechanisms are poorly understood. We report here the identification and characterization of a kinase, triacylglycerol accumulation regulator1 (TAR1), that is a member of the yeast (Saccharomyces cerevisiae) Yet another kinase1 (Yak1) subfamily in the dual-specificity tyrosine phosphorylation-regulated kinase family in a green alga (Chlamydomonas reinhardtii). The kinase domain of TAR1 showed auto- and transphosphorylation activities. A TAR1-defective mutant, tar1-1, accumulated TAG to levels 0.5- and 0.1-fold of those of a wild-type strain in sulfur (S)- and nitrogen (N)-deficient conditions, respectively. In N-deficient conditions, tar1-1 showed more pronounced arrest of cell division than the wild type, had increased cell size and cell dry weight, and maintained chlorophyll and photosynthetic activity, which were not observed in S-deficient conditions. In N-deficient conditions, global changes in expression levels of N deficiency-responsive genes in N assimilation and tetrapyrrole metabolism were noted between tar1-1 and wild-type cells. These results indicated that TAR1 is a regulator of TAG accumulation in S- and N-deficient conditions, and it functions in cell growth and repression of photosynthesis in conditions of N deficiency. © 2015 American Society of Plant Biologists. All Rights Reserved.

  5. Dietary Betaine Supplementation Increases Fgf21 Levels to Improve Glucose Homeostasis and Reduce Hepatic Lipid Accumulation in Mice

    PubMed Central

    Ejaz, Asma; Martinez-Guino, Laura; Goldfine, Allison B.; Ribas-Aulinas, Francesc; De Nigris, Valeria; Ribó, Sílvia; Gonzalez-Franquesa, Alba; Garcia-Roves, Pablo M.; Li, Elizabeth; Dreyfuss, Jonathan M.; Gall, Walt; Kim, Jason K.; Bottiglieri, Teodoro; Villarroya, Francesc; Gerszten, Robert E.

    2016-01-01

    Identifying markers of human insulin resistance may permit development of new approaches for treatment and prevention of type 2 diabetes. To this end, we analyzed the fasting plasma metabolome in metabolically characterized human volunteers across a spectrum of insulin resistance. We demonstrate that plasma betaine levels are reduced in insulin-resistant humans and correlate closely with insulin sensitivity. Moreover, betaine administration to mice with diet-induced obesity prevents the development of impaired glucose homeostasis, reduces hepatic lipid accumulation, increases white adipose oxidative capacity, and enhances whole-body energy expenditure. In parallel with these beneficial metabolic effects, betaine supplementation robustly increased hepatic and circulating fibroblast growth factor (Fgf)21 levels. Betaine administration failed to improve glucose homeostasis and liver fat content in Fgf21−/− mice, demonstrating that Fgf21 is necessary for betaine’s beneficial effects. Together, these data indicate that dietary betaine increases Fgf21 levels to improve metabolic health in mice and suggest that betaine supplementation merits further investigation as a supplement for treatment or prevention of type 2 diabetes in humans. PMID:26858359

  6. Engineering alfalfa to accumulate useful caffeic acid derivatives and characterization of hydroxycinnamoyl-CoA transferases from legumes

    USDA-ARS?s Scientific Manuscript database

    Some forages crops, such as red clover, accumulate high levels of caffeic acid derivatives. Oxidation of these o-diphenols to quinones by endogenous polyphenol oxidases (PPOs) and the subsequent reactions of these quinones (probably with endogenous plant proteases) result in a significant reduction ...

  7. Proline accumulation and its implication in cold tolerance of regenerable maize callus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duncan, D.R.; Widholm, J.M.

    1987-03-01

    Embryogenic callus of maize (Zea mays L.) inbreds B37wx, H99, H99/sup 3/H95, Mo17, and Pa91 accumulated proline to levels 2.1 to 2.5 times that of control callus when subjected to mannitol-induced water stress, cool temperatures (19/sup 0/C) and abscisic acid (ABA). A combination of 0.53 molar mannitol plus 0.1 millimolar ABA induced a proline accumulation to about 4.5 times that of control callus, equivalent to approximately 0.18 millimoles proline per gram fresh weight of callus. Proline accumulation was directly related to the level of mannitol in the medium. Levels of ABA greater than 1.0 micromolar were required in the mediummore » to induce proline accumulation comparable to that induced by mannitol. Mannitol and ABA levels that induced maximum accumulation of proline also inhibited callus growth and increased tolerance to cold. Proline (12 millimolar) added to culture media also increased the tolerance of callus to 4/sup 0/C. The increased cold tolerance induced by the combination of mannitol and ABA has permitted the storage of the maize inbreds A632, A634Ht, B37wx, C103DTrf, Fr27rhm, H99, Pa91, Va35, and W117Ht at 4/sup 0/C for 90 days which is more than double the typical survival time of callus. These studies show that proline accumulation increase the cold tolerance of regenerable maize callus.« less

  8. Variation in the accumulation levels of N,N-dimethyltryptamine in micropropagated trees and in in vitro cultures of Mimosa tenuiflora.

    PubMed

    Nicasio, María Del Pilar; Villarreal, María Luisa; Gillet, Françoise; Bensaddek, Lamine; Fliniaux, Marc-André

    2005-01-01

    The present article reports the accumulation of N,N-dimethyltryptamine and its metabolic precursors (tryptophan, tryptamine) in different organs of micropropagated Mimosa tenuiflora trees (leaves, flowers and bark) subjected to seasonal variations (January and June), as well as in in vitro cultures (plantlets and calluses) of this plant species. The accumulation of all the tested compounds varied according to the organ, the month of collection, and age of the plant material. In all cases, the neurotoxic compound N,N-dimethyltryptamine (DMT) was detected with the lowest concentration 0.01% dry weight (DW) in flowers, and the highest 0.33% DW in bark. For the in vitro cultures, DMT was present in high yields in plantlets (0.1-0.2% DW), while in calluses this compound was initially detected but its concentration decreased significantly in the subsequent subcultures.

  9. Cardiac and metabolic changes in long-term high fructose-fat fed rats with severe obesity and extensive intramyocardial lipid accumulation.

    PubMed

    Axelsen, Lene N; Lademann, Jacob B; Petersen, Jørgen S; Holstein-Rathlou, Niels-Henrik; Ploug, Thorkil; Prats, Clara; Pedersen, Henrik D; Kjølbye, Anne Louise

    2010-06-01

    Metabolic syndrome and obesity-related diseases are affecting more and more people in the Western world. The basis for an effective treatment of these patients is a better understanding of the underlying pathophysiology. Here, we characterize fructose- and fat-fed rats (FFFRs) as a new animal model of metabolic syndrome. Sprague-Dawley rats were fed a 60 kcal/100 kcal fat diet with 10% fructose in the drinking water. After 6, 12, 18, 24, 36, and 48 wk of feeding, blood pressure, glucose tolerance, plasma insulin, glucose, and lipid levels were measured. Cardiac function was examined by in vivo pressure volume measurements, and intramyocardial lipid accumulation was analyzed by confocal microscopy. Cardiac AMP-activated kinase (AMPK) and hepatic phosphoenolpyruvate carboxykinase (PEPCK) levels were measured by Western blotting. Finally, an ischemia-reperfusion study was performed after 56 wk of feeding. FFFRs developed severe obesity, decreased glucose tolerance, increased serum insulin and triglyceride levels, and an initial increased fasting glucose, which returned to control levels after 24 wk of feeding. The diet had no effect on blood pressure but decreased hepatic PEPCK levels. FFFRs showed significant intramyocardial lipid accumulation, and cardiac hypertrophy became pronounced between 24 and 36 wk of feeding. FFFRs showed no signs of cardiac dysfunction during unstressed conditions, but their hearts were much more vulnerable to ischemia-reperfusion and had a decreased level of phosphorylated AMPK at 6 wk of feeding. This study characterizes a new animal model of the metabolic syndrome that could be beneficial in future studies of metabolic syndrome and cardiac complications.

  10. Response of salt-marsh carbon accumulation to climate change.

    PubMed

    Kirwan, Matthew L; Mudd, Simon M

    2012-09-27

    About half of annual marine carbon burial takes place in shallow water ecosystems where geomorphic and ecological stability is driven by interactions between the flow of water, vegetation growth and sediment transport. Although the sensitivity of terrestrial and deep marine carbon pools to climate change has been studied for decades, there is little understanding of how coastal carbon accumulation rates will change and potentially feed back on climate. Here we develop a numerical model of salt marsh evolution, informed by recent measurements of productivity and decomposition, and demonstrate that competition between mineral sediment deposition and organic-matter accumulation determines the net impact of climate change on carbon accumulation in intertidal wetlands. We find that the direct impact of warming on soil carbon accumulation rates is more subtle than the impact of warming-driven sea level rise, although the impact of warming increases with increasing rates of sea level rise. Our simulations suggest that the net impact of climate change will be to increase carbon burial rates in the first half of the twenty-first century, but that carbon-climate feedbacks are likely to diminish over time.

  11. System level analysis of cacao seed ripening reveals a sequential interplay of primary and secondary metabolism leading to polyphenol accumulation and preparation of stress resistance.

    PubMed

    Wang, Lei; Nägele, Thomas; Doerfler, Hannes; Fragner, Lena; Chaturvedi, Palak; Nukarinen, Ella; Bellaire, Anke; Huber, Werner; Weiszmann, Jakob; Engelmeier, Doris; Ramsak, Ziva; Gruden, Kristina; Weckwerth, Wolfram

    2016-08-01

    Theobroma cacao and its popular product, chocolate, are attracting attention due to potential health benefits including antioxidative effects by polyphenols, anti-depressant effects by high serotonin levels, inhibition of platelet aggregation and prevention of obesity-dependent insulin resistance. The development of cacao seeds during fruit ripening is the most crucial process for the accumulation of these compounds. In this study, we analyzed the primary and the secondary metabolome as well as the proteome during Theobroma cacao cv. Forastero seed development by applying an integrative extraction protocol. The combination of multivariate statistics and mathematical modelling revealed a complex consecutive coordination of primary and secondary metabolism and corresponding pathways. Tricarboxylic acid (TCA) cycle and aromatic amino acid metabolism dominated during the early developmental stages (stages 1 and 2; cell division and expansion phase). This was accompanied with a significant shift of proteins from phenylpropanoid metabolism to flavonoid biosynthesis. At stage 3 (reserve accumulation phase), metabolism of sucrose switched from hydrolysis into raffinose synthesis. Lipids as well as proteins involved in lipid metabolism increased whereas amino acids and N-phenylpropenoyl amino acids decreased. Purine alkaloids, polyphenols, and raffinose as well as proteins involved in abiotic and biotic stress accumulated at stage 4 (maturation phase) endowing cacao seeds the characteristic astringent taste and resistance to stress. In summary, metabolic key points of cacao seed development comprise the sequential coordination of primary metabolites, phenylpropanoid, N-phenylpropenoyl amino acid, serotonin, lipid and polyphenol metabolism thereby covering the major compound classes involved in cacao aroma and health benefits. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  12. Variation of radiation level and radionuclide enrichment in high background area.

    PubMed

    Shetty, P K; Narayana, Y

    2010-12-01

    Significantly high radiation level and radionuclide concentration along Quilon beach area of coastal Kerala have been reported by several investigators. Detailed gamma radiation level survey was carried out using a portable scintillometer. Detailed studies on radionuclides concentration in different environmental matrices of high background areas were undertaken in the coastal areas of Karunagapalli, Kayankulam, Chavara, Neendakara and Kollam to study the distribution and enrichment of the radionuclides in the region. The absorbed gamma dose rates in air in high background area are in the range 43-17,400nGyh⁻¹. Gamma radiation level is found to be maximum at a distance of 20m from the sea waterline in all beaches. The soil samples collected from different locations were analysed for primordial radionuclides by gamma spectrometry. The activity of primordial radionuclides was determined for the different size fractions of soil to study the enrichment pattern. The highest activity of (232)Th and (226)Ra was found to be enriched in 125-63μ size fraction. The preferential accumulation of (40)K was found in <63μ fraction. The minimum (232)Th activity was 30.2Bqkg⁻¹, found in 1000-500μ particle size fraction at Kollam and maximum activity of 3250.4Bqkg⁻¹ was observed in grains of size 125-63μ at Neendakara. The lowest (226)Ra activity observed was 33.9Bqkg⁻¹ at Neendakara in grains of size 1000-500μ and the highest activity observed was 482.6Bqkg⁻¹ in grains of size 125-63μ in Neendakara. The highest (40)K activity found was 1923Bqkg⁻¹ in grains of size <63μ for a sample collected from Neendakara. A good correlation was observed between computed dose and measured dose in air. The correlation between (232)Th and (226)Ra was also moderately high. The results of these investigations are presented and discussed in this paper. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Organic carbon accumulation in Brazilian mangal sediments

    NASA Astrophysics Data System (ADS)

    Sanders, Christian J.; Smoak, Joseph M.; Sanders, Luciana M.; Sathy Naidu, A.; Patchineelam, Sambasiva R.

    2010-12-01

    This study reviews the organic carbon (OC) accumulation rates in mangrove forests, margins and intertidal mudflats in geographically distinct areas along the Brazilian coastline (Northeastern to Southern). Our initial results indicate that the mangrove forests in the Northeastern region of Brazil are accumulating more OC (353 g/m 2/y) than in the Southeastern areas (192 g/m 2/y) being that the sediment accumulation rates, 2.8 and 2.5 mm/y, and OC content ˜7.1% and ˜5.8% (dry sediment weight) were contributing factors to the discrepancies between the forests. The intertidal mudflats on the other hand showed substantially greater OC accumulation rates, sedimentation rates and content 1129 g/m 2/y and 234 g/m 2/y; 7.3 and 3.4 mm/y; 10.3% and ˜2.7% (OC of dry sediment weight content), respectively, in the Northeastern compared to the Southeastern region. Mangrove forests in the South-Southeastern regions of Brazil may be more susceptible to the rising sea level, as they are geographically constricted by the vast mountain ranges along the coastline.

  14. Gama-aminobutyric acid accumulation in Elsholtzia splendens in response to copper toxicity*

    PubMed Central

    Yang, Xiao-e; Peng, Hong-yun; Tian, Sheng-ke

    2005-01-01

    A solution with different Cu supply levels was cultured to investigate gama-aminobutyric acid (GABA) accumulation in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species. Increasing Cu from 0.25 to 500 μmol/L significantly enhanced levels of GABA and histidine (His), but considerably decreased levels of aspartate (Asp) and glutamate (Glu) in the leaves. The leaf Asp level negatively correlated with leaf Cu level, while leaf GABA level positively correlated with leaf Cu level. The leaf Glu level negatively correlated with leaf GABA level in Elsholtzia splendens. The depletion of leaf Glu may be related to the enhanced synthesis of leaf GABA under Cu stress. PMID:15633244

  15. Poplar trees for phytoremediation of high levels of nitrate and applications in bioenergy.

    PubMed

    Castro-Rodríguez, Vanessa; García-Gutiérrez, Angel; Canales, Javier; Cañas, Rafael A; Kirby, Edward G; Avila, Concepción; Cánovas, Francisco M

    2016-01-01

    The utilization of high amounts of nitrate fertilizers for crop yield leads to nitrate pollution of ground and surface waters. In this study, we report the assimilation and utilization of nitrate luxuriant levels, 20 times more than the highest N fertilizer application in Europe, by transgenic poplars overexpressing a cytosolic glutamine synthetase (GS1). In comparison with the wild-type controls, transgenic plants grown under high N levels exhibited increased biomass (171.6%) and accumulated higher levels of proteins, chlorophylls and total sugars such as glucose, fructose and sucrose. These plants also exhibited greater nitrogen-use efficiency particularly in young leaves, suggesting that they are able to translocate most of the resources to the above-ground part of the plant to produce biomass. The transgenic poplar transcriptome was greatly affected in response to N availability with 1237 genes differentially regulated in high N, while only 632 genes were differentially expressed in untransformed plants. Many of these genes are essential in the adaptation and response against N excess and include those involved in photosynthesis, cell wall formation and phenylpropanoid biosynthesis. Cellulose production in the transgenic plants was fivefold higher than in control plants, indicating that transgenic poplars represent a potential feedstock for applications in bioenergy. In conclusion, our results show that GS transgenic poplars can be used not only for improving growth and biomass production but also as an important resource for potential phytoremediation of nitrate pollution. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  16. Abscisic Acid accumulation in spinach leaf slices in the presence of penetrating and nonpenetrating solutes.

    PubMed

    Creelman, R A; Zeevaart, J A

    1985-01-01

    Abscisic acid (ABA) accumulated in detached, wilted leaves of spinach (Spinacia oleracea L. cv Savoy Hybrid 612) and reached a maximum level within 3 to 4 hours. The increase in ABA over that found in detached turgid leaves was approximately 10-fold. The effects of water stress could be mimicked by the use of thin slices of spinach leaves incubated in the presence of 0.6 molar mannitol, a compound which causes plasmolysis (loss of turgor). About equal amounts of ABA were found both in the leaf slices and in detached leaves, whereas 2 to 4 times more ABA accumulated in the medium than in the slices. When spinach leaf slices were incubated with ethylene glycol, a compound which rapidly penetrates the cell membrane causing a decrease in the osmotic potential of the tissue and only transient loss of turgor, no ABA accumulated. Ethylene glycol was not inhibitory with respect to ABA accumulation. Spinach leaf slices incubated in both ethylene glycol and mannitol had ABA levels similar to those found when slices were incubated with mannitol alone. Increases similar to those found with mannitol also occurred when Aquacide III, a highly purified form of polyethylene glycol, was used. Aquacide III causes cytorrhysis, a situation similar to that found in wilted leaves. Thus, it appears that loss of turgor is essential for ABA accumulation.When spinach leaf slices were incubated with solutes which are supposed to disturb membrane integrity (KHSO(3), 2-propanol, or KCl) no increase in ABA was observed. These data indicate that, with respect to the accumulation of ABA, mannitol caused a physical stress (loss of turgor) rather than a chemical stress (membrane damage).

  17. Long-term strength and damage accumulation in laminates

    NASA Astrophysics Data System (ADS)

    Dzenis, Yuris A.; Joshi, Shiv P.

    1993-04-01

    A modified version of the probabilistic model developed by authors for damage evolution analysis of laminates subjected to random loading is utilized to predict long-term strength of laminates. The model assumes that each ply in a laminate consists of a large number of mesovolumes. Probabilistic variation functions for mesovolumes stiffnesses as well as strengths are used in the analysis. Stochastic strains are calculated using the lamination theory and random function theory. Deterioration of ply stiffnesses is calculated on the basis of the probabilities of mesovolumes failures using the theory of excursions of random process beyond the limits. Long-term strength and damage accumulation in a Kevlar/epoxy laminate under tension and complex in-plane loading are investigated. Effects of the mean level and stochastic deviation of loading on damage evolution and time-to-failure of laminate are discussed. Long-term cumulative damage at the time of the final failure at low loading levels is more than at high loading levels. The effect of the deviation in loading is more pronounced at lower mean loading levels.

  18. Three-Dimensional Ultrastructural Study of Oil and Astaxanthin Accumulation during Encystment in the Green Alga Haematococcus pluvialis

    PubMed Central

    Matsuura, Hazuki; Nango, Nobuhito; Hirata, Aiko; Kawano, Shigeyuki

    2013-01-01

    Haematococcus pluvialis is a freshwater species of green algae and is well known for its accumulation of the strong antioxidant astaxanthin, which is used in aquaculture, various pharmaceuticals, and cosmetics. High levels of astaxanthin are present in cysts, which rapidly accumulate when the environmental conditions become unfavorable for normal cell growth. It is not understood, however, how accumulation of high levels of astaxanthin, which is soluble in oil, becomes possible during encystment. Here, we performed ultrastructural 3D reconstruction based on over 350 serial sections per cell to visualize the dynamics of astaxanthin accumulation and subcellular changes during the encystment of H. pluvialis. This study showcases the marked changes in subcellular elements, such as chloroplast degeneration, in the transition from green coccoid cells to red cyst cells during encystment. In green coccoid cells, chloroplasts accounted for 41.7% of the total cell volume, whereas the relative volume of astaxanthin was very low (0.2%). In contrast, oil droplets containing astaxanthin predominated in cyst cells (52.2%), in which the total chloroplast volume was markedly decreased (9.7%). Volumetric observations also demonstrated that the relative volumes of the cell wall, starch grains, pyrenoids, mitochondria, the Golgi apparatus, and the nucleus in a cyst cell are smaller than those in green coccid cells. Our data indicated that chloroplasts are degraded, resulting in a net-like morphology, but do not completely disappear, even at the red cyst stage. PMID:23326471

  19. Sludge accumulation pattern inside oxidation ditch case study.

    PubMed

    Fouad, Moharram; El-Morsy, Ahmed

    2014-01-01

    The sludge accumulation pattern of an oxidation ditch (OD) plant treating municipal wastewater was observed under dry and wet weather conditions, during 3 years of operation. The accumulation patterns along the ditches and their rates were revealed. In addition, the composition of the accumulation was investigated. Finally, the ratio of sand and volatile particles, mixed liquor suspended solids (MLSS), and mixed liquor volatile suspended solids, as well as the removal efficiency were also observed against the accumulated sludge. Further, a laboratory-scale channel was used to investigate the settleability of grit after mixing with variable values of MLSS. The observed results indicated that the economical design and operation of ODs using a velocity value between 0.3-0.35 m/s is not recommended, to avoid the settling of all solids. High values of MLSS and sludge age need high horizontal velocity (more than 0.35 m/s) and more power to avoid settling problems and system failure. The influence of flow velocity on the sludge settleability was studied, enabling better planning of future ditch design and operation.

  20. Accumulation and toxicity of monophenyl arsenicals in rat endothelial cells.

    PubMed

    Hirano, Seishiro; Kobayashi, Yayoi; Hayakawa, Toru; Cui, Xing; Yamamoto, Megumi; Kanno, Sanae; Shraim, Amjad

    2005-01-01

    Clark 1 (diphenylarsine chloride) and Clark 2 (diphenylarsine cyanide) were used as chemical weapon agents (CWA), and the soil contamination by these CWA and their degraded products, diphenyl and phenyl arsenicals, has been one of the most serious environmental issues. In a series of comparisons in toxicity between trivalent and pentavalent arsenicals we investigated differences in the accumulation and toxicity of phenylarsine oxide (PAO3+) and phenylarsonic acid (PAA5+) in rat heart microvascular endothelial cells. Both the cellular association and toxicity of PAO3+ were much higher than those of PAA5+, and LC50 values of PAO3+ and PAA5+ were calculated to be 0.295 microM and 1.93 mM, respectively. Buthionine sulfoximine, a glutathione depleter, enhanced the cytotoxicity of both PAO3+ and PAA5+. N-Acetyl-L-cysteine (NAC) reduced the cytotoxicity and induction of heme oxygenase-1 (HO-1) mRNA in PAO3+-exposed cells, while NAC affected neither the cytotoxicity nor the HO-1 mRNA level in PAA5+-exposed cells. The effect of NAC may be due to a strong affinity of PAO3+ to thiol groups because both NAC and GSH inhibited the cellular accumulation of PAO3+, but PAA3+ increased tyrosine phosphorylation levels of cellular proteins. These results indicate that the inhibition of protein phosphatases as well as the high affinity to cellular components may confer PAO3+ the high toxicity.

  1. Deleterious effects of neuronal accumulation of glycogen in flies and mice

    PubMed Central

    Duran, Jordi; Tevy, María Florencia; Garcia-Rocha, Mar; Calbó, Joaquim; Milán, Marco; Guinovart, Joan J

    2012-01-01

    Under physiological conditions, most neurons keep glycogen synthase (GS) in an inactive form and do not show detectable levels of glycogen. Nevertheless, aberrant glycogen accumulation in neurons is a hallmark of patients suffering from Lafora disease or other polyglucosan disorders. Although these diseases are associated with mutations in genes involved in glycogen metabolism, the role of glycogen accumulation remains elusive. Here, we generated mouse and fly models expressing an active form of GS to force neuronal accumulation of glycogen. We present evidence that the progressive accumulation of glycogen in mouse and Drosophila neurons leads to neuronal loss, locomotion defects and reduced lifespan. Our results highlight glycogen accumulation in neurons as a direct cause of neurodegeneration. PMID:22549942

  2. High levels of histones promote whole-genome-duplications and trigger a Swe1WEE1-dependent phosphorylation of Cdc28CDK1.

    PubMed

    Maya Miles, Douglas; Peñate, Xenia; Sanmartín Olmo, Trinidad; Jourquin, Frederic; Muñoz Centeno, Maria Cruz; Mendoza, Manuel; Simon, Marie-Noelle; Chavez, Sebastian; Geli, Vincent

    2018-03-27

    Whole-genome duplications (WGDs) have played a central role in the evolution of genomes and constitute an important source of genome instability in cancer. Here, we show in Saccharomyces cerevisiae that abnormal accumulations of histones are sufficient to induce WGDs. Our results link these WGDs to a reduced incorporation of the histone variant H2A.Z to chromatin. Moreover, we show that high levels of histones promote Swe1 WEE1 stabilisation thereby triggering the phosphorylation and inhibition of Cdc28 CDK1 through a mechanism different of the canonical DNA damage response. Our results link high levels of histones to a specific type of genome instability that is quite frequently observed in cancer and uncovers a new mechanism that might be able to respond to high levels of histones. © 2018, Maya Miles et al.

  3. Multivariate characterization of elements accumulated in King Bolete Boletus edulis mushroom at lowland and high mountain regions.

    PubMed

    Falandysz, J; Kunito, T; Kubota, R; Bielawski, L; Frankowska, A; Falandysz, Justyna J; Tanabe, S

    2008-12-01

    Based on ICP-MS, ICP-OES, HG-AAS, CV-AAS and elementary instrumental analysis of King Bolete collected from four sites of different soil bedrock geochemistry considered could be as mushroom abundant in certain elements. King's Bolete fruiting bodies are very rich in K (> 20 mg/g dry weight), rich in Ca, Mg, Na, Rb and Zn (> 100 microg/g dw), and relatively also rich in Ag, Cd, Cs, Cu, Fe, Mn and Se (> 10 microg/g dw). The caps of King Bolete when compared to stipes around two-to three-fold more abundant are in Ag, Cd, Cs, Cu, Hg, K, Mg, Mo, N, Rb, Se and Zn. King Bolete collected at the lowland and mountain sites showed Ag, Ba, Co, Cr, Hg, K, Mg, Mn, Mo and Na in caps in comparable concentrations, and specimens from the mountain areas accumulated more Cd and Sb. Elements such as Al, Pb and Rb occurred at relatively elevated concentration in King Bolete picked up at the metal ores-rich region of the Sudety Mountains. Because of high bioconcentration potential King Bolete at the background sites accumulate in fruiting bodies great concentrations of problematic elements such as Cd, Pb and Hg, i.e. up to nearly 20, 3 and 5 microg/g dw, on the average, respectively. The interdependence among determined mineral elements examined were using the principal components analysis (PCA) method. The PCA explained 56% of the total variance. The metals tend to cluster together (Ba, Cd, Cs, Cr, Ga, Rb, Se, Sr and V; K and Mg; Cu and Mo). The results provided useful environmental and nutritional background level information on 26 minerals as the composition of King Bolete from the sites of different bedrock soil geochemistry.

  4. Plastic Accumulation in the Mediterranean Sea

    PubMed Central

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J. Ignacio; Ubeda, Bárbara; Gálvez, José Á.; Irigoien, Xabier; Duarte, Carlos M.

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region. PMID:25831129

  5. Plastic accumulation in the Mediterranean sea.

    PubMed

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J Ignacio; Ubeda, Bárbara; Gálvez, José Á; Irigoien, Xabier; Duarte, Carlos M

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

  6. Cadmium accumulation in different rice cultivars and screening for pollution-safe cultivars of rice.

    PubMed

    Yu, Hui; Wang, Junli; Fang, Wei; Yuan, Jiangang; Yang, Zhongyi

    2006-11-01

    Large areas of contaminated land are being used for agricultural production in some countries due to the high demand for food. To minimize the influx of pollutants to the human food chain through consumption of agricultural products, we propose the concept of pollution-safe cultivars (PSCs), i.e. cultivars whose edible parts accumulate a specific pollutant at a level low enough for safe consumption, even when grown in contaminated soil. We tested the feasibility of the PSC concept by growing 43 cultivars of paddy rice (Oryza sativa L., including 20 normal and 23 hybrid cultivars) under a high (75.69-77.55 mg kg(-1)) and a low (1.75-1.85 mg kg(-1)) cadmium (Cd) exposure. These pot experiments took place in the spring and summer of 2004. At the low level of Cd exposure, 30 out of the 43 tested cultivars were found to be Cd-PSCs. Grain Cd concentrations were highly correlated (p<0.01) between the two experiments, suggesting that Cd accumulation in rice grain is genotype-dependent and that the selection of PSCs is possible, at least at a certain level of soil contamination. No Cd-PSCs were found under the high level of Cd exposure. Yield was enhanced in some cultivars and depressed in others in response to elevated soil Cd, indicating that farmers cannot rely on yield depression as an indicator of toxicity of the grains. It is therefore important and feasible to screen for PSCs and to establish PSC breeding programs to effectively and efficiently reduce the risk of human exposure to soil pollutants, such as Cd, through crop consumption.

  7. Why consider subseabed disposal of high-level nuclear waste

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heath, G. R.; Hollister, C. D.; Anderson, D. R.

    1980-01-01

    Large areas of the deep seabed warrant assessment as potential disposal sites for high-level radioactive waste because: (1) they are far from seismically and tectonically active lithospheric plate boundaries; (2) they are far from active or young volcanos; (3) they contain thick layers of very uniform fine-grained clays; (4) they are devoid of natural resources likely to be exploited in the forseeable future; (5) the geologic and oceanographic processes governing the deposition of sediments in such areas are well understood, and are remarkably insensitive to past oceanographic and climatic changes; and (6) sedmentary records of tens of millions of yearsmore » of slow, uninterrupted deposition of fine grained clay support predictions of the future stability of such sites. Data accumulated to date on the permeability, ion-retardation properties, and mechanical strength of pelagic clay sediments indicate that they can act as a primary barrier to the escape of buried nuclides. Work in progress should determine within the current decade whether subseabed disposal is environmentally acceptable and technically feasible, as well as address the legal, political and social issues raised by this new concept.« less

  8. Toxic Ipomeamarone Accumulation in Healthy Parts of Sweetpotato (Ipomoea batatas L. Lam) Storage Roots upon Infection by Rhizopus stolonifer

    PubMed Central

    2015-01-01

    Furanoterpenoid accumulation in response to microbial attack in rotting sweetpotatoes has long been linked to deaths and lung edema of cattle in the world. However, it is not known whether furanoterpenoid ipomeamarone accumulates in the healthy-looking parts of infected sweetpotato storage roots. This is critical for effective utilization as animal feed and assessment of the potential negative impact on human health. Therefore, we first identified the fungus from infected sweetpotatoes as a Rhizopus stolonifer strain and then used it to infect healthy sweetpotato storage roots for characterization of furanoterpenoid content. Ipomeamarone and its precursor, dehydroipomeamarone, were identified through spectroscopic analyses, and detected in all samples and controls at varying concentrations. Ipomeamarone concentration was at toxic levels in healthy-looking parts of some samples. Our study provides fundamental information on furanoterpenoids in relation to high levels reported that could subsequently affect cattle on consumption and high ipomeamarone levels in healthy-looking parts. PMID:25418792

  9. Evolution of high-level resistance during low-level antibiotic exposure.

    PubMed

    Wistrand-Yuen, Erik; Knopp, Michael; Hjort, Karin; Koskiniemi, Sanna; Berg, Otto G; Andersson, Dan I

    2018-04-23

    It has become increasingly clear that low levels of antibiotics present in many environments can select for resistant bacteria, yet the evolutionary pathways for resistance development during exposure to low amounts of antibiotics remain poorly defined. Here we show that Salmonella enterica exposed to sub-MIC levels of streptomycin evolved high-level resistance via novel mechanisms that are different from those observed during lethal selections. During lethal selection only rpsL mutations are found, whereas at sub-MIC selection resistance is generated by several small-effect resistance mutations that combined confer high-level resistance via three different mechanisms: (i) alteration of the ribosomal RNA target (gidB mutations), (ii) reduction in aminoglycoside uptake (cyoB, nuoG, and trkH mutations), and (iii) induction of the aminoglycoside-modifying enzyme AadA (znuA mutations). These results demonstrate how the strength of the selective pressure influences evolutionary trajectories and that even weak selective pressures can cause evolution of high-level resistance.

  10. Palmitic Acid Reduces Circulating Bone Formation Markers in Obese Animals and Impairs Osteoblast Activity via C16-Ceramide Accumulation.

    PubMed

    Alsahli, Ahmad; Kiefhaber, Kathryn; Gold, Tziporah; Muluke, Munira; Jiang, Hongfeng; Cremers, Serge; Schulze-Späte, Ulrike

    2016-05-01

    Obesity and impaired lipid metabolism increase circulating and local fatty acid (FA) levels. Our previous studies showed that a high high-saturated -fat diet induced greater bone loss in mice than a high high-unsaturated-fat diet due to increased osteoclast numbers and activity. The impact of elevated FA levels on osteoblasts is not yet clear. We induced obesity in 4 week old male mice using a palmitic acid (PA)- or oleic acid (OA)-enriched high fat high-fat diet (HFD) (20 % of calories from FA), and compared them to mice on a normal (R) caloric diet (10 % of calories from FA). We collected serum to determine FA and bone metabolism marker levels. Primary osteoblasts were isolated; cultured in PA, OA, or control (C) medium; and assessed for mineralization activity, gene expression, and ceramide levels. Obese animals in the PA and OA groups had significantly lower serum levels of bone formation markers P1NP and OC compared to normal weight animals (*p < 0.001), with the lowest marker levels in animals on an PA-enriched HFD (*p < 0.001). Accordingly, elevated levels of PA significantly reduced osteoblast mineralization activity in vitro (*p < 0.05). Elevated PA intake significantly increased C16 ceramide accumulation. This accumulation was preventable through inhibition of SPT2 (serine palmitoyl transferase 2) using myriocin. Elevated levels of PA reduce osteoblast function in vitro and bone formation markers in vivo. Our findings suggest that saturated PA can compromise bone health by affecting osteoblasts, and identify a potential mechanism through which obesity promotes bone loss.

  11. Enhanced decomposition offsets enhanced productivity and soil carbon accumulation in coastal wetlands responding to climate change

    USGS Publications Warehouse

    Kirwan, M.L.; Blum, L.K.

    2011-01-01

    Coastal wetlands are responsible for about half of all carbon burial in oceans, and their persistence as a valuable ecosystem depends largely on the ability to accumulate organic material at rates equivalent to relative sea level rise. Recent work suggests that elevated CO2 and temperature warming will increase organic matter productivity and the ability of marshes to survive sea level rise. However, we find that organic decomposition rates increase by about 12% per degree of warming. Our measured temperature sensitivity is similar to studies from terrestrial systems, twice as high as the response of salt marsh productivity to temperature warming, and roughly equivalent to the productivity response associated with elevated CO2 in C3 marsh plants. Therefore, enhanced CO2 and warmer temperatures may actually make marshes less resilient to sea level rise, and tend to promote a release of soil carbon. Simple projections indicate that elevated temperatures will increase rates of sea level rise more than any acceleration in organic matter accumulation, suggesting the possibility of a positive feedback between climate, sea level rise, and carbon emissions in coastal environments.

  12. Accumulation and ultrastructural distribution of copper in Elsholtzia splendens *

    PubMed Central

    Peng, Hong-yun; Yang, Xiao-e; Tian, Sheng-ke

    2005-01-01

    Copper accumulation and intracellular distribution in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species, was investigated by transmission electron microscope (TEM) and gradient centrifugation techniques. Copper concentrations in roots, stems and leaves of E. splendens increased with increasing Cu levels in solution. After exposure to 500 μmol/L Cu for 8 d, about 1000 mg/kg Cu were accumulated in the stem and 250 mg/kg Cu in the leaf of E. splendens. At 50 µmol/L Cu, no significant toxicity was observed in the chloroplast and mitochondrion within its leaf cells, but separation appeared at the cytoplasm and the cell wall within the root cells. At >250 µmol/L Cu, both root and leaf organelles in E. splendens were damaged heavily by excessive Cu in vivo. Copper subcellular localization in the plant leaf after 8 days’ exposure to 500 µmol/L Cu using gradient centrifugation techniques was found to be decreased in the order: chloroplast>cell wall>soluble fraction>other organelles. The plant root cell wall was found to be the site of highest Cu localization. Increase of Cu exposure time from 8 d to 16 d, increased slightly Cu concentration in cell wall fraction in roots and leaves, while that in the chloroplast fraction decreased in leaves of the plants grown in both 0.25 μmol/L and 500 μmol/L Cu. TEM confirmed that much more Cu localized in cell walls of E. splendens roots and leaves, but also more Cu localized in E. splendens’ chloroplast when the plant is exposed to Cu levels>250 μmol/L, as compared to those in the plant grown in 0.25 μmol/L Cu. Copper treatment at levels>250 μmol/L caused pronounced damage in the leaf chloroplast and root organelles. Copper localization in cell walls and chloroplasts could mainly account for the high detoxification of Cu in E. splendens. PMID:15822140

  13. Characters related to higher starch accumulation in cassava storage roots

    PubMed Central

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

  14. Characters related to higher starch accumulation in cassava storage roots.

    PubMed

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-02-19

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

  15. Selenium accumulation in plants--phytotechnological applications and ecological implications.

    PubMed

    Valdez Barillas, José Rodolfo; Quinn, Colin F; Pilon-Smits, Elizabeth A H

    2011-01-01

    Selenium (Se) is an essential trace element for many organisms including humans, yet toxic at higher levels. Both Se deficiency and toxicity are problems worldwide. Since plants readily accumulate and volatilize Se, they may be used both as a source of dietary Se and for removing excess Se from the environment. Plant species differ in their capacity to metabolize and accumulate Se, from non-Se accumulators (< 100 mg Se/kg DW), to Se-accumulators (100-1000 mg Se/kg DW) to Se hyperaccumulators (> 1,000 mg Se/kg DW). Here we review plant mechanisms of Se metabolism in these various plant types. We also summarize results from genetic engineering that have led to enhanced plant Se accumulation, volatilization, and/or tolerance, including field studies. Before using Se-accumulating plants at a large scale we need to evaluate the ecological implications. Research so far indicates that plant Se accumulation significantly affects the plant's ecological interactions below and above ground. Selenium canprotect plants from fungal pathogens and from a variety of invertebrate and vertebrate herbivores, due to both deterrence and toxicity. However, specialist (Se-tolerant herbivores), detritivores and endophytes appear to utilize Se hyperaccumulator plants as a resource. These findings are relevant for managing phytoremediation of Se and similar elements.

  16. Stochastic Analysis and Forecasts of the Patterns of Speed, Acceleration, and Levels of Material Stock Accumulation in Society.

    PubMed

    Fishman, Tomer; Schandl, Heinz; Tanikawa, Hiroki

    2016-04-05

    The recent acceleration of urbanization and industrialization of many parts of the developing world, most notably in Asia, has resulted in a fast-increasing demand for and accumulation of construction materials in society. Despite the importance of physical stocks in society, the empirical assessment of total material stock of buildings and infrastructure and reasons for its growth have been underexplored in the sustainability literature. We propose an innovative approach for explaining material stock dynamics in society and create a country typology for stock accumulation trajectories using the ARIMA (Autoregressive Integrated Moving Average) methodology, a stochastic approach commonly used in business studies and economics to inspect and forecast time series. This enables us to create scenarios for future demand and accumulation of building materials in society, including uncertainty estimates. We find that the so-far overlooked aspect of acceleration trends of material stock accumulation holds the key to explaining material stock growth, and that despite tremendous variability in country characteristics, stock accumulation is limited to only four archetypal growth patterns. The ability of nations to change their pattern will be a determining factor for global sustainability.

  17. Maturation of Rb+ and PAH accumulation by rabbit anterior uvea and choroid plexus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krupin, T.; Fritz, C.; Becker, B.

    In vitro accumulation of radioactive para-aminohippuric acid (/sup 3/H-PAH) and rubidium (/sup 86/Rb+) by the anterior uvea, ciliary processes, and the choroid plexus was evaluated in tissues from newborn and various aged rabbits. Accumulation of PAH was present in the anterior uvea at 1 day of age (tissue to media ratio, T/M, of 2.1 +/- 0.2) and remained at this level for the first 14 days of life. Accumulation did not rise to adult levels until 21 days of age (T/M 5.5 +/- 0.6). Rubidium accumulation in the anterior uvea, a measure of Na+, K+-pump activity, was higher than adultmore » values 6 hr after birth (T/M25.2 +/- 0.9). Activity remained elevated through day 28 and did not fall to adult levels until day 60 (T/M 13.4 +/- 0.6). Accumulation studies on isolated ciliary processes were similar to those obtained from anterior uveal tissue. Daily subcutaneous injections of penicillin (300,000 units/kg/day) for 1 week had no effect on anterior uvea PAH accumulation (penicillin T/M was 1.7 +/- 0.1 and saline control T/M was 2.0 +/- 0.2). Accumulation of either /sup 3/H-PAH or /sup 86/Rb+ by the choroid plexus was present 1 day after birth in amounts that were similar to adult values and did not change during the 90 days of testing.« less

  18. Differential accumulation of β-carotene and tissue specific expression of phytoene synthase (MaPsy) gene in banana (Musa sp) cultivars.

    PubMed

    Dhandapani, R; Singh, V P; Arora, A; Bhattacharya, R C; Rajendran, Ambika

    2017-12-01

    An experiment was conducted with twelve major Indian banana cultivars to investigate the molecular relationship between the differential accumulation of β-carotene in peel and pulp of the banana fruit and carotenoid biosynthetic pathway genes. The high performance liquid chromatography showed that all banana cultivars accumulated two-three fold more β-carotene in non-edible portion of the banana fruit. However, Nendran , a famous orange fleshed cultivar of South India, had high β-carotene content (1362 µg/100 g) in edible pulp. The gene encoding Musa accuminata phytoene synthase ( MaPsy ) was successfully amplified using a pair of degenerate primers designed from Oncidium orchid. The deduced amino acid sequences shared a high level of identity to phytoene synthase gene from other plants. Gene expression analysis confirmed the presence of two isoforms ( MaPsy1 and MaPsy2 ) of MaPsy gene in banana fruits. Presence of two isoforms of MaPsy gene in peel and one in pulp confirmed the differential accumulation of β-carotene in banana fruits. However, Nendran accumulated more β-carotene in edible pulp due to presence of both the isoforms of MaPsy gene. Thus, carotenoid accumulation is a tissue specific process strongly dependent on differential expression pattern of two isoforms of MaPsy gene in banana.

  19. Accumulation and transfer of contaminants in killer whales (Orcinus orca) from Norway: indications for contaminant metabolism.

    PubMed

    Wolkers, Hans; Corkeron, Peter J; Van Parijs, Sofie M; Similä, Tiu; Van Bavel, Bert

    2007-08-01

    Blubber tissue of one subadult and eight male adult killer whales was sampled in Northern Norway in order to assess the degree and type of contaminant exposure and transfer in the herring-killer whale link of the marine food web. A comprehensive selection of contaminants was targeted, with special attention to toxaphenes and polybrominated diphenyl ethers (PBDEs). In addition to assessing exposure and food chain transfer, selective accumulation and metabolism issues also were addressed. Average total polychlorinated biphenyl (PCB) and pesticide levels were similar, approximately 25 microg/g lipid, and PBDEs were approximately 0.5 microg/g. This makes killer whales one of the most polluted arctic animals, with levels exceeding those in polar bears. Comparing the contamination of the killer whale's diet with the diet of high-arctic species such as white whales reveals six to more than 20 times higher levels in the killer whale diet. The difference in contaminant pattern between killer whales and their prey and the metabolic index calculated suggested that these cetaceans have a relatively high capacity to metabolize contaminants. Polychlorinated biphenyls, chlordanes, and dichlorodiphenyldichloro-ethylene (DDE) accumulate to some degree in killer whales, although toxaphenes and PBDEs might be partly broken down.

  20. Beneficial Effect of Bis(Hinokitiolato)Zn Complex on High-fat Diet-induced Lipid Accumulation in Mouse Liver and Kidney.

    PubMed

    Naito, Yuki; Yoshikawa, Yutaka; Yoshizawa, Katsuhiko; Takenouchi, Akiko; Yasui, Hiroyuki

    2017-01-01

    Metabolic syndrome-induced lifestyle-related diseases include diabetes mellitus (DM) and hypertension, and Zn-based compounds have effects on DM. We aimed to investigate the ameliorating effects of bis(hinokitiolato)Zn, [Zn(hkt) 2 ] on lipid metabolism in the liver and kidney, histopathologically. We used a high-fat diet (HFD)-fed C57BL/6J mouse model and administered a diet containing 10-20 mg Zn/kg body weight (BW) or 20 mg pioglitazone/kg BW as the positive control. After the treatments, we collected blood, liver, and kidney samples and morphologically evaluated the mouse organs for fat accumulation. After a 4-month HFD administration, ectopic fat deposition was detected in the liver and kidney. Furthermore, Zn accumulation in the liver and kidney increased following [Zn(hkt) 2 ] treatment, that reduced lipid accumulations and lipid toxicity in these tissues. The results of this study suggest that [Zn(hkt) 2 ] could be a novel anti-dyslipidaemia compound for treating diet-induced obesity. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  1. Deep soil layer is fundamental for evaluating carbon accumulation in agroecosystems

    NASA Astrophysics Data System (ADS)

    Dal Ferro, Nicola; Morari, Francesco; Simonetti, Gianluca; Polese, Riccardo; Berti, Antonio

    2015-04-01

    Soil organic carbon (SOC) is essential to secure key ecosystem services such as the provision of food and other biomass production, the filtering, buffering and transformation capacity and the climate regulation. It has been estimated that approximately 57% of the globally emitted C (8.7 Gt y-1) to the atmosphere is adsorbed by biospheric C pools, ascertaining the potential soil C sink capacity of managed ecosystems at 55 to 78 Gt, of which only 50 to 66% attainable. Therefore it is essential the full knowledge of soil management practices that can affect SOC dynamics and, in turn, climate change. Several studies focussed on the evaluation of the best cropping management practices to accumulate C in the soil profile. Nevertheless, in most cases soil analyses were made in the topsoil (generally in the 0-30 cm layer), ignoring the effect of C translocation in the deeper soil profile as a result of tillage practices, crop root deepening etc. In this context, in a long-term experiment established in the early 1960s, we quantified the SOC accumulation within the soil profile (0-90 cm) and evaluate the effects of different cropping system on SOC dynamics. The experiment is located at the experimental farm of the University of Padova, in northeastern Italy. The trial compares four rotations with three levels of mineral fertilisation and with or without organic fertilisation. The rotations considered are: continuous crops (grain maize, forage maize, winter wheat and permanent meadow); two-year (maize-wheat); four-year (sugarbeet, soybean, wheat, maize) and six-year (maize, sugarbeet, maize, wheat, alfalfa, alfalfa) with different levels of mineral, organic and mixed fertilisations. Crops with superficially developed rooting systems (e.g. permanent meadow) highly increased SOC only in the topsoil. This effect was enhanced by the contribution of organic amendment-C. Root-derived carbon played a pivotal role also in the deepest soil profile (60-90 cm) by increasing the SOC

  2. Deleterious effects of neuronal accumulation of glycogen in flies and mice.

    PubMed

    Duran, Jordi; Tevy, María Florencia; Garcia-Rocha, Mar; Calbó, Joaquim; Milán, Marco; Guinovart, Joan J

    2012-08-01

    Under physiological conditions, most neurons keep glycogen synthase (GS) in an inactive form and do not show detectable levels of glycogen. Nevertheless, aberrant glycogen accumulation in neurons is a hallmark of patients suffering from Lafora disease or other polyglucosan disorders. Although these diseases are associated with mutations in genes involved in glycogen metabolism, the role of glycogen accumulation remains elusive. Here, we generated mouse and fly models expressing an active form of GS to force neuronal accumulation of glycogen. We present evidence that the progressive accumulation of glycogen in mouse and Drosophila neurons leads to neuronal loss, locomotion defects and reduced lifespan. Our results highlight glycogen accumulation in neurons as a direct cause of neurodegeneration. Copyright © 2012 EMBO Molecular Medicine.

  3. Maximum likelihood decoding analysis of Accumulate-Repeat-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    Repeat-Accumulate (RA) codes are the simplest turbo-like codes that achieve good performance. However, they cannot compete with Turbo codes or low-density parity check codes (LDPC) as far as performance is concerned. The Accumulate Repeat Accumulate (ARA) codes, as a subclass of LDPC codes, are obtained by adding a pre-coder in front of RA codes with puncturing where an accumulator is chosen as a precoder. These codes not only are very simple, but also achieve excellent performance with iterative decoding. In this paper, the performance of these codes with (ML) decoding are analyzed and compared to random codes by very tight bounds. The weight distribution of some simple ARA codes is obtained, and through existing tightest bounds we have shown the ML SNR threshold of ARA codes approaches very closely to the performance of random codes. We have shown that the use of precoder improves the SNR threshold but interleaving gain remains unchanged with respect to RA code with puncturing.

  4. Size effect of elemental selenium nanoparticles (Nano-Se) at supranutritional levels on selenium accumulation and glutathione S-transferase activity.

    PubMed

    Peng, Dungeng; Zhang, Jinsong; Liu, Qingliang; Taylor, Ethan Will

    2007-10-01

    It has been shown that 36 nm Nano-Se has lower toxicity than selenite or selenomethionine, but these forms of selenium (Se) all possess similar ability to increase selenoenzyme levels. The size of nanoparticles plays an important role in their biological activity: as expected, 5-200 nm Nano-Se can directly scavenge free radicals in vitro in a size-dependent fashion. However, in Se-deficient cells and Se-deficient mice, the size effect of Nano-Se on increasing selenoenzymes and liver Se disappears unexpectedly. We hypothesize that under conditions of Se deficiency, the avidity of Se uptake mechanisms may be increased to maintain the biosynthesis of selenoenzymes, which are fundamental for redox homeostasis. This increased avidity may override the potential advantage of small size Nano-Se seen under Se-replete conditions, thereby eliminating the size effect. Once selenoenzymes have been saturated, Se uptake mechanisms may downregulate; accordingly, the size effect of Nano-Se can then reappear. To test this hypothesis, Se-deficient mice were administered either 36 or 90 nm Nano-Se at supranutritional doses, in both a short-term model and a single-dose model. Under these conditions, Nano-Se showed a size effect on Se accumulation and glutathione S-transferase (GST) activity. A size effect of Nano-Se was found in 15 out of 18 total comparisons between sizes at the same dose and time in the two models. Furthermore, the magnitude of the size effect was more prominent on Se accumulation than on GST activity. GST is strictly regulated by transcriptional and translational mechanisms, so its increase in activity normally does not exceed 3-fold. In contrast, the homeostasis of Se accumulation is not as tightly controlled. In the present experiments, GST activity had reached or was approaching saturation, but liver Se was far below saturation. Therefore, our results strongly suggest that the saturation profile of the tested biomarker has an impact on the size effect of Nano

  5. The impact of selected soil organic matter fractions on the PAH accumulation in the agricultural soils from areas of different anthropopressure.

    PubMed

    Klimkowicz-Pawlas, Agnieszka; Smreczak, Bozena; Ukalska-Jaruga, Aleksandra

    2017-04-01

    The level of 16PAH accumulation was determined in 75 soil samples collected from two agricultural regions of Poland corresponding to the smallest Polish administrative unit at the LAU 2 level. Both regions are characterised by similar territory and soil cover but different history of pollution and different pressure of anthropogenic factors. Overall accumulation of Σ16PAHs in the upper soil layer was within a wide range with the median value of 291 and 1253 μg kg -1 for a non-contaminated and high anthropopressure region, respectively. Nearly 75 % of the total polycyclic aromatic hydrocarbon (PAH) pool was represented by high molecular four-to-six-ring compounds, deriving mainly from combustion sources. The total organic carbon (C org ) and black carbon (BC) contents were the main parameters associated with the PAH accumulation in soils, and the level of the regional anthropopressure was considered a significant factor. The strongest links of PAHs/BC (r = 0.70, p ≤ 0.05) were found in the region of high anthropopressure, characterized by a relatively high content of BC (up to 45.3 g kg -1 ), which tends to heavily adsorb hydrocarbons. In a region of low influence exerted by anthropopressure, the PAH/C org or PAH/BC relationships were not observed, which may suggest different diffuse sources of PAH origin and a dominant role of other organic matter fractions in retention of PAHs in soils.

  6. Geomorphic control of landscape carbon accumulation

    USGS Publications Warehouse

    Rosenbloom, N.A.; Harden, J.W.; Neff, J.C.; Schimel, D.S.

    2006-01-01

    We use the CREEP process-response model to simulate soil organic carbon accumulation in an undisturbed prairie site in Iowa. Our primary objectives are to identify spatial patterns of carbon accumulation, and explore the effect of erosion on basin-scale C accumulation. Our results point to two general findings. First, redistribution of soil carbon by erosion results in a net increase in basin-wide carbon storage relative to a noneroding environment. Landscape-average mean residence times are increased in an eroding landscape owing to the burial/preservation of otherwise labile C. Second, field observations taken along a slope transect may overlook significant intraslope variations in carbon accumulation. Spatial patterns of modeled deep C accumulation are complex. While surface carbon with its relatively short equilibration time is predictable from surface properties, deep carbon is strongly influenced by the landscape's geomorphic and climatic history, resulting in wide spatial variability. Convergence and divergence associated with upland swales and interfluves result in bimodal carbon distributions in upper and mid slopes; variability in carbon storage within modeled mid slopes was as high as simulated differences between erosional shoulders and depositional valley bottoms. The bimodality of mid-slope C variability in the model suggests that a three-dimensional sampling strategy is preferable over the traditional two-dimensional analog or "catena" approach. Copyright 2006 by the American Geophysical Union.

  7. 2D Effective Electron Mass at the Fermi Level in Accumulation and Inversion Layers of MOSFET Nano Devices.

    PubMed

    Singh, S L; Singh, S B; Ghatak, K P

    2018-04-01

    In this paper an attempt is made to study the 2D Fermi Level Mass (FLM) in accumulation and inversion layers of nano MOSFET devices made of nonlinear optical, III-V, ternary, Quaternary, II-VI, IV-VI, Ge and stressed materials by formulating 2D carrier dispersion laws on the basis of k p formalism and considering the energy band constants of a particular material. It is observed taking accumulation and inversion layers of Cd3As2, CdGeAs2, InSb, Hg1-xCdxTe and In1-xGaxAsyP1-y lattice matched to InP, CdS, GaSb and Ge as examples that the FLM depends on sub band index for nano MOSFET devices made of Cd3As2 and CdGeAs2 materials which is the characteristic features such 2D systems. Besides, the FLM depends on the scattering potential in all the cases and the same mass changes with increasing surface electric field. The FLM exists in the band gap which is impossible without heavy doping.

  8. Toxicity and accumulation of mercury in three species of crabs with different osmoregulatory capacities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bianchini, A.; Gilles, R.

    1996-07-01

    Synergism between mercury and salinity has been shown in invertebrates. Two authors have tied to correlate salinity effects with a higher or lower accumulation of mercury. Zauke, demonstrated lower mercury levels in several benthic invertebrates from limnic regions of the Elbe estuary when compared to those from Marine regions. On the other hand, Kendall did not report any significant difference in mercury concentrations in benthic macroinvertebrates throughout a salinity gradient in two estuaries from Georgia. In species hyperosmoregulating in diluted media, it could, however, be considered that the high water turnover would favor mercury accumulation. In this context, one couldmore » also expect a relationship between environmental salinity and mercury toxicity in different euryhaline species depending on their osmoregulatory capacities. We have tested this hypothesis analyzing the toxic effects and accumulation of mercury in three euryhaline crabs presenting different osmoregulatory capacities: Eriocheir sinensis (strong hyperosmoregulator), Carcinus maenas (weak hyperosmoregulator) and Cancer pagurus (osmoconformer). 16 refs., 4 figs., 1 tab.« less

  9. Tyrosine decarboxylase activity of enterococci grown in media with different nutritional potential: tyramine and 2-phenylethylamine accumulation and tyrDC gene expression.

    PubMed

    Bargossi, Eleonora; Tabanelli, Giulia; Montanari, Chiara; Lanciotti, Rosalba; Gatto, Veronica; Gardini, Fausto; Torriani, Sandra

    2015-01-01

    The ability to accumulate tyramine and 2-phenylethylamine by two strains of Enterococcus faecalis and two strains Enterococcus faecium was evaluated in two cultural media added or not with tyrosine. All the enterococcal strains possessed a tyrosine decarboxylase (tyrDC) which determined tyramine accumulation in all the conditions tested, independently on the addition of high concentration of free tyrosine. Enterococci differed in rate and level of biogenic amines accumulation. E. faecalis EF37 and E. faecium FC12 produced tyramine in high amount since the exponential growth phase, while 2-phenylethylamine was accumulated when tyrosine was depleted. E. faecium FC12 and E. faecalis ATCC 29212 showed a slower tyraminogenic activity which took place mainly in the stationary phase up to 72 h of incubation. Moreover, E. faecalis ATCC 29212 produced 2-phenylethylamine only in the media without tyrosine added. In BHI added or not with tyrosine the tyrDC gene expression level differed considerably depending on the strains and the growth phase. In particular, the tyrDC gene expression was high during the exponential phase in rich medium for all the strains and subsequently decreased except for E. faecium FC12. Even if tyrDC presence is common among enterococci, this study underlines the extremely variable decarboxylating potential of strains belonging to the same species, suggesting strain-dependent implications in food safety.

  10. Glomerular disease augments kidney accumulation of synthetic anionic polymers.

    PubMed

    Liu, Gary W; Prossnitz, Alexander N; Eng, Diana G; Cheng, Yilong; Subrahmanyam, Nithya; Pippin, Jeffrey W; Lamm, Robert J; Ngambenjawong, Chayanon; Ghandehari, Hamidreza; Shankland, Stuart J; Pun, Suzie H

    2018-06-02

    Polymeric drug carriers can alter the pharmacokinetics of their drug cargoes, thereby improving drug therapeutic index and reducing side effects. Understanding and controlling polymer properties that drive tissue-specific accumulation is critical in engineering targeted drug delivery systems. For kidney disease applications, targeted drug delivery to renal cells that reside beyond the charge- and size-selective glomerular filtration barrier could have clinical potential. However, there are limited reports on polymer properties that might enhance kidney accumulation. Here, we studied the effects of molecular weight and charge on the in vivo kidney accumulation of polymers in health and disease. We synthesized a panel of well-defined polymers by atom transfer radical polymerization to answer several questions. First, the biodistribution of low molecular weight (23-27 kDa) polymers composed of various ratios of neutral:anionic monomers (1:0, 1:1, 1:4) in normal mice was determined. Then, highly anionic (1:4 monomer ratio) low molecular and high molecular weight (47 kDa) polymers were tested in both normal and experimental focal segmental glomerulosclerosis (FSGS) mice, a model that results in loss of glomerular filtration selectivity. Through these studies, we observed that kidney-specific polymer accumulation increases with anionic monomer content, but not molecular weight; experimental FSGS increases kidney accumulation of anionic polymers; and anionic polymers accumulate predominantly in proximal tubule cells, with some distribution in kidney glomeruli. These findings can be applied to the design of polymeric drug carriers to enhance or mitigate kidney accumulation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Abscisic Acid Accumulation in Spinach Leaf Slices in the Presence of Penetrating and Nonpenetrating Solutes 1

    PubMed Central

    Creelman, Robert A.; Zeevaart, Jan A. D.

    1985-01-01

    Abscisic acid (ABA) accumulated in detached, wilted leaves of spinach (Spinacia oleracea L. cv Savoy Hybrid 612) and reached a maximum level within 3 to 4 hours. The increase in ABA over that found in detached turgid leaves was approximately 10-fold. The effects of water stress could be mimicked by the use of thin slices of spinach leaves incubated in the presence of 0.6 molar mannitol, a compound which causes plasmolysis (loss of turgor). About equal amounts of ABA were found both in the leaf slices and in detached leaves, whereas 2 to 4 times more ABA accumulated in the medium than in the slices. When spinach leaf slices were incubated with ethylene glycol, a compound which rapidly penetrates the cell membrane causing a decrease in the osmotic potential of the tissue and only transient loss of turgor, no ABA accumulated. Ethylene glycol was not inhibitory with respect to ABA accumulation. Spinach leaf slices incubated in both ethylene glycol and mannitol had ABA levels similar to those found when slices were incubated with mannitol alone. Increases similar to those found with mannitol also occurred when Aquacide III, a highly purified form of polyethylene glycol, was used. Aquacide III causes cytorrhysis, a situation similar to that found in wilted leaves. Thus, it appears that loss of turgor is essential for ABA accumulation. When spinach leaf slices were incubated with solutes which are supposed to disturb membrane integrity (KHSO3, 2-propanol, or KCl) no increase in ABA was observed. These data indicate that, with respect to the accumulation of ABA, mannitol caused a physical stress (loss of turgor) rather than a chemical stress (membrane damage). PMID:16664022

  12. Improving the satellite communication efficiency of the accumulative acknowledgement strategies

    NASA Astrophysics Data System (ADS)

    Duarte, Otto Carlos M. B.; de Lima, Heliomar Medeiros

    The performances of two finite buffer error recovery strategies are analyzed. In both strategies the retransmission request decision between selective repeat and continuous retransmission is based on an imminent buffer overflow condition. These are accumulative acknowledgment schemes, but in the second strategy the selective-repeat control frame is uniquely an individual negative acknowledgment. The two strategies take advantage of the availability of a greater buffer capacity, making the most of the selective repeat, postponing the sending of a continuous retransmission request. Numerical results show a better performance very close to the ideal, but it does not integrally conform to the high-level data link control (HDLC) procedures. It is shown that these strategies are well suited for high-speed data transfer in the high-error-rate satellite environment.

  13. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... pressures not exceeding the maximum allowable working pressures. When an accumulator forms an integral part...

  14. Multilevel modeling of damage accumulation processes in metals

    NASA Astrophysics Data System (ADS)

    Kurmoiartseva, K. A.; Trusov, P. V.; Kotelnikova, N. V.

    2017-12-01

    To predict the behavior of components and constructions it is necessary to develop the methods and mathematical models which take into account the self-organization of microstructural processes and the strain localization. The damage accumulation processes and the evolution of material properties during deformation are important to take into account. The heterogeneity of the process of damage accumulation is due to the appropriate physical mechanisms at the scale levels, which are lower than the macro-level. The purpose of this work is to develop a mathematical model for analyzing the behavior of polycrystalline materials that allows describing the damage accumulation processes. Fracture is the multistage and multiscale process of the build-up of micro- and mesodefects over the wide range of loading rates. The formation of microcracks by mechanisms is caused by the interactions of the dislocations of different slip systems, barriers, boundaries and the inclusions of the secondary phase. This paper provides the description of some of the most well-known models of crack nucleation and also suggests the structure of a mathematical model based on crystal plasticity and dislocation models of crack nucleation.

  15. Low-level awareness accompanies "unconscious" high-level processing during continuous flash suppression.

    PubMed

    Gelbard-Sagiv, Hagar; Faivre, Nathan; Mudrik, Liad; Koch, Christof

    2016-01-01

    The scope and limits of unconscious processing are a matter of ongoing debate. Lately, continuous flash suppression (CFS), a technique for suppressing visual stimuli, has been widely used to demonstrate surprisingly high-level processing of invisible stimuli. Yet, recent studies showed that CFS might actually allow low-level features of the stimulus to escape suppression and be consciously perceived. The influence of such low-level awareness on high-level processing might easily go unnoticed, as studies usually only probe the visibility of the feature of interest, and not that of lower-level features. For instance, face identity is held to be processed unconsciously since subjects who fail to judge the identity of suppressed faces still show identity priming effects. Here we challenge these results, showing that such high-level priming effects are indeed induced by faces whose identity is invisible, but critically, only when a lower-level feature, such as color or location, is visible. No evidence for identity processing was found when subjects had no conscious access to any feature of the suppressed face. These results suggest that high-level processing of an image might be enabled by-or co-occur with-conscious access to some of its low-level features, even when these features are not relevant to the processed dimension. Accordingly, they call for further investigation of lower-level awareness during CFS, and reevaluation of other unconscious high-level processing findings.

  16. Iron Accumulates in Huntington’s Disease Neurons: Protection by Deferoxamine

    PubMed Central

    Chen, Jianfang; Lai, Barry; Zhang, Zhaojie; Duce, James A.; Lam, Linh Q.; Volitakis, Irene; Bush, Ashley I.; Hersch, Steven

    2013-01-01

    Huntington’s disease (HD) is a progressive neurodegenerative disorder caused by a polyglutamine-encoding CAG expansion in the huntingtin gene. Iron accumulates in the brains of HD patients and mouse disease models. However, the cellular and subcellular sites of iron accumulation, as well as significance to disease progression are not well understood. We used independent approaches to investigate the location of brain iron accumulation. In R6/2 HD mouse brain, synchotron x-ray fluorescence analysis revealed iron accumulation as discrete puncta in the perinuclear cytoplasm of striatal neurons. Further, perfusion Turnbull’s staining for ferrous iron (II) combined with transmission electron microscope ultra-structural analysis revealed increased staining in membrane bound peri-nuclear vesicles in R6/2 HD striatal neurons. Analysis of iron homeostatic proteins in R6/2 HD mice revealed decreased levels of the iron response proteins (IRPs 1 and 2) and accordingly decreased expression of iron uptake transferrin receptor (TfR) and increased levels of neuronal iron export protein ferroportin (FPN). Finally, we show that intra-ventricular delivery of the iron chelator deferoxamine results in an improvement of the motor phenotype in R6/2 HD mice. Our data supports accumulation of redox-active ferrous iron in the endocytic / lysosomal compartment in mouse HD neurons. Expression changes of IRPs, TfR and FPN are consistent with a compensatory response to an increased intra-neuronal labile iron pool leading to increased susceptibility to iron-associated oxidative stress. These findings, together with protection by deferoxamine, support a potentiating role of neuronal iron accumulation in HD. PMID:24146952

  17. Selective accumulation of biotin in arterial chemoreceptors: requirement for carotid body exocytotic dopamine secretion.

    PubMed

    Ortega-Sáenz, Patricia; Macías, David; Levitsky, Konstantin L; Rodríguez-Gómez, José A; González-Rodríguez, Patricia; Bonilla-Henao, Victoria; Arias-Mayenco, Ignacio; López-Barneo, José

    2016-12-15

    Biotin, a vitamin whose main role is as a coenzyme for carboxylases, accumulates at unusually large amounts within cells of the carotid body (CB). In biotin-deficient rats biotin rapidly disappears from the blood; however, it remains at relatively high levels in CB glomus cells. The CB contains high levels of mRNA for SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin. Animals with biotin deficiency exhibit pronounced metabolic lactic acidosis. Remarkably, glomus cells from these animals have normal electrical and neurochemical properties. However, they show a marked decrease in the size of quantal dopaminergic secretory events. Inhibitors of the vesicular monoamine transporter 2 (VMAT2) mimic the effect of biotin deficiency. In biotin-deficient animals, VMAT2 protein expression decreases in parallel with biotin depletion in CB cells. These data suggest that dopamine transport and/or storage in small secretory granules in glomus cells depend on biotin. Biotin is a water-soluble vitamin required for the function of carboxylases as well as for the regulation of gene expression. Here, we report that biotin accumulates in unusually large amounts in cells of arterial chemoreceptors, carotid body (CB) and adrenal medulla (AM). We show in a biotin-deficient rat model that the vitamin rapidly disappears from the blood and other tissues (including the AM), while remaining at relatively high levels in the CB. We have also observed that, in comparison with other peripheral neural tissues, CB cells contain high levels of SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin. Biotin-deficient rats show a syndrome characterized by marked weight loss, metabolic lactic acidosis, aciduria and accelerated breathing with normal responsiveness to hypoxia. Remarkably, CB cells from biotin-deficient animals have normal electrophysiological and neurochemical (ATP levels and catecholamine synthesis) properties; however

  18. Selective accumulation of biotin in arterial chemoreceptors: requirement for carotid body exocytotic dopamine secretion

    PubMed Central

    Ortega‐Sáenz, Patricia; Macías, David; Levitsky, Konstantin L.; Rodríguez‐Gómez, José A.; González‐Rodríguez, Patricia; Bonilla‐Henao, Victoria; Arias‐Mayenco, Ignacio

    2016-01-01

    Key points Biotin, a vitamin whose main role is as a coenzyme for carboxylases, accumulates at unusually large amounts within cells of the carotid body (CB).In biotin‐deficient rats biotin rapidly disappears from the blood; however, it remains at relatively high levels in CB glomus cells. The CB contains high levels of mRNA for SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin.Animals with biotin deficiency exhibit pronounced metabolic lactic acidosis. Remarkably, glomus cells from these animals have normal electrical and neurochemical properties. However, they show a marked decrease in the size of quantal dopaminergic secretory events.Inhibitors of the vesicular monoamine transporter 2 (VMAT2) mimic the effect of biotin deficiency. In biotin‐deficient animals, VMAT2 protein expression decreases in parallel with biotin depletion in CB cells.These data suggest that dopamine transport and/or storage in small secretory granules in glomus cells depend on biotin. Abstract Biotin is a water‐soluble vitamin required for the function of carboxylases as well as for the regulation of gene expression. Here, we report that biotin accumulates in unusually large amounts in cells of arterial chemoreceptors, carotid body (CB) and adrenal medulla (AM). We show in a biotin‐deficient rat model that the vitamin rapidly disappears from the blood and other tissues (including the AM), while remaining at relatively high levels in the CB. We have also observed that, in comparison with other peripheral neural tissues, CB cells contain high levels of SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin. Biotin‐deficient rats show a syndrome characterized by marked weight loss, metabolic lactic acidosis, aciduria and accelerated breathing with normal responsiveness to hypoxia. Remarkably, CB cells from biotin‐deficient animals have normal electrophysiological and neurochemical (ATP levels and catecholamine

  19. Analysis of Hanle-effect signals observed in Si-channel spin accumulation devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Takamura, Yota, E-mail: takamura@spin.pe.titech.ac.jp; Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552; Akushichi, Taiju

    2014-05-07

    We reexamined curve-fitting analysis for spin-accumulation signals observed in Si-channel spin-accumulation devices, employing widely-used Lorentz functions and a new formula developed from the spin diffusion equation. A Si-channel spin-accumulation device with a high quality ferromagnetic spin injector was fabricated, and its observed spin-accumulation signals were verified. Experimentally obtained Hanle-effect signals for spin accumulation were not able to be fitted by a single Lorentz function and were reproduced by the newly developed formula. Our developed formula can represent spin-accumulation signals and thus analyze Hanle-effect signals.

  20. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation.

    PubMed

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-01-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O 2 exposure conditions: low (10 mg L -1 ) and medium or high (the stoichiometrically required amount to oxidize all wine total SO 2 plus 18 or 32 mg L -1 , respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O 2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO 2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO 2 , in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity toward ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity toward ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones

  1. Formation and Accumulation of Acetaldehyde and Strecker Aldehydes during Red Wine Oxidation

    PubMed Central

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-01-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O2 exposure conditions: low (10 mg L−1) and medium or high (the stoichiometrically required amount to oxidize all wine total SO2 plus 18 or 32 mg L−1, respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO2, in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity toward ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity toward ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones derived

  2. Formation and accumulation of acetaldehyde and Strecker aldehydes during red wine oxidation

    NASA Astrophysics Data System (ADS)

    Bueno, Mónica; Marrufo-Curtido, Almudena; Carrascón, Vanesa; Fernández-Zurbano, Purificación; Escudero, Ana; Ferreira, Vicente

    2018-02-01

    The main aim of the present work is to study the accumulation of acetaldehyde and Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, methional, phenylacetaldehyde) during the oxidation of red wines, and to relate the patterns of accumulation to the wine chemical composition. For that, eight different wines, extensively chemically characterized, were subjected at 25°C to three different controlled O2 exposure conditions: low (10 mg L-1) and medium or high (the stoichiometrically required amount to oxidize all wine total SO2 plus 18 or 32 mg L-1, respectively). Levels of volatile aldehydes and carbonyls were then determined and processed by different statistical techniques. Results showed that young wines (<2 years-old bottled wines) hardly accumulate any acetaldehyde regardless of the O2 consumed. In contrast, aged wines (>3 years-old bottled wines) accumulated acetaldehyde while their content in SO2 was not null, and the aged wine containing lowest polyphenols accumulated it throughout the whole process. Models suggest that the ability of a wine to accumulate acetaldehyde is positively related to its content in combined SO2, in epigallocatechin and to the mean degree of polymerization, and negatively to its content in Aldehyde Reactive Polyphenols (ARPs) which, attending to our models, are anthocyanins and small tannins. The accumulation of Strecker aldehydes is directly proportional to the wine content in the amino acid precursor, being the proportionality factor much higher for aged wines, except for phenylacetaldehyde, for which the opposite pattern was observed. Models suggest that non-aromatic Strecker aldehydes share with acetaldehyde a strong affinity towards ARPs and that the specific pattern of phenylacetaldehyde is likely due to a much reduced reactivity towards ARPs, to the possibility that diacetyl induces Strecker degradation of phenyl alanine and to the potential higher reactivity of this amino acid to some quinones derived from

  3. Enterobacter cloacae administration induces hepatic damage and subcutaneous fat accumulation in high-fat diet fed mice.

    PubMed

    Keskitalo, Anniina; Munukka, Eveliina; Toivonen, Raine; Hollmén, Maija; Kainulainen, Heikki; Huovinen, Pentti; Jalkanen, Sirpa; Pekkala, Satu

    2018-01-01

    Accumulating evidence indicates that gut microbiota plays a significant role in obesity, insulin resistance and associated liver disorders. Family Enterobacteriaceae and especially Enterobacter cloacae strain B29 have been previously linked to obesity and hepatic damage. The underlying mechanisms, however, remain unclear. Therefore, we comprehensively examined the effects of E. cloacae subsp. cloacae (ATCC® 13047™) administration on host metabolism of mice fed with high-fat diet (HFD). C57BL/6N mice were randomly divided into HFD control, chow control, and E. cloacae treatment groups. The E. cloacae treatment group received live bacterial cells in PBS intragastrically twice a week, every other week for 13 weeks. Both control groups received PBS intragastrically. After the 13-week treatment period, the mice were sacrificed for gene and protein expression and functional analyses. Our results show that E. cloacae administration increased subcutaneous fat mass and the relative proportion of hypertrophic adipocytes. Both subcutaneous and visceral fat had signs of decreased insulin signaling and elevated lipolysis that was reflected in higher serum glycerol levels. In addition, E. cloacae -treated mice had significantly higher hepatic AST and AST/ALT ratio, and their liver histology indicated fibrosis, demonstrating that E. cloacae subsp. cloacae administration promotes hepatic damage in HFD fed mice.

  4. Higher transcription levels in ascorbic acid biosynthetic and recycling genes were associated with higher ascorbic acid accumulation in blueberry.

    PubMed

    Liu, Fenghong; Wang, Lei; Gu, Liang; Zhao, Wei; Su, Hongyan; Cheng, Xianhao

    2015-12-01

    In our preliminary study, the ripe fruits of two highbush blueberry (Vaccinium corymbosum L.) cultivars, cv 'Berkeley' and cv 'Bluecrop', were found to contain different levels of ascorbic acid. However, factors responsible for these differences are still unknown. In the present study, ascorbic acid content in fruits was compared with expression profiles of ascorbic acid biosynthetic and recycling genes between 'Bluecrop' and 'Berkeley' cultivars. The results indicated that the l-galactose pathway was the predominant route of ascorbic acid biosynthesis in blueberry fruits. Moreover, higher expression levels of the ascorbic acid biosynthetic genes GME, GGP, and GLDH, as well as the recycling genes MDHAR and DHAR, were associated with higher ascorbic acid content in 'Bluecrop' compared with 'Berkeley', which indicated that a higher efficiency ascorbic acid biosynthesis and regeneration was likely to be responsible for the higher ascorbic acid accumulation in 'Bluecrop'. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each accumulator...

  6. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each accumulator...

  7. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each accumulator...

  8. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each accumulator...

  9. The Diamond Window with Boron-Doped Layers for the Output of Microwave Radiation at High Peak and Average Power Levels

    NASA Astrophysics Data System (ADS)

    Ivanov, O. A.; Kuzikov, S. V.; Vikharev, A. A.; Vikharev, A. L.; Lobaev, M. A.

    2017-10-01

    We propose a novel design of the barrier window for the output of microwave radiation at high peak and average power levels. A window based on a plate of polycrystalline CVD diamond with thin (nanometer-thick) boron-doped layers with increased conductivity is considered. Such a window, which retains the low radiation loss due to the small total thickness of the conductive layers and the high thermal conductivity inherent in diamond, prevents accumulation of a static charge on its surface, on the one hand, and allows one to produce a static electric field on the surface of the doped layer, which impedes the development of a multipactor discharge, on the other hand. In this case, a high level of the power of the transmitted radiation and a large passband width are ensured by choosing the configuration of the field in the form of a traveling wave inside the window.

  10. Abscisic Acid accumulates at positive turgor potential in excised soybean seedling growing zones.

    PubMed

    Creelman, R A; Mullet, J E

    1991-04-01

    Abscisic acid (ABA) accumulated in soybean (Glycine max [L.] Merr. cv Williams) hypocotyl elongating regions when seedlings were transferred to low water potential vermiculite (Psi = -0.3 megapascals) even though positive turgor is retained in this tissue. Accumulation of ABA in growing zones could occur from de novo biosynthesis within this tissue or transport from adjacent nongrowing zones. Both growing and nongrowing hypocotyl and root tissues accumulated significant levels of ABA when excised and dehydrated to reduce turgor. Surprisingly, excised growing zones (which experienced no water loss) also accumulated ABA when incubated in darkness for 4 hours at 100% relative humidity and 29 degrees C. Induction of ABA accumulation in the excised elongating region of the hypocotyl was not caused by disruption of root pressure or wounding. While excision of hypocotyl elongating regions induced ABA accumulation, no change in either extensin or p33 mRNA levels was observed. Accumulation of extensin or p33 mRNA required more severe wounding. This suggests that ABA is not involved in the response of these genes in wounded tissue and that wound signals are not causing ABA accumulation in excised tissue. Accumulation of ABA in excised elongating regions was correlated with growth inhibition and a decline in turgor to the yield threshold (Psi;(p) = 0.37 megapascals; R Matyssek, S Maruyama, JS Boyer [1988] Plant Physiol 86: 1163-1167). Inhibiting hypocotyl growth by transferring seedlings to lower temperatures or light did not cause ABA accumulation. We conclude that induction of ABA accumulation in growing zones is more sensitive to changes in turgor than the induction which occurs in mature tissues.

  11. Establishment of an Arabidopsis callus system to study the interrelations of biosynthesis, degradation and accumulation of carotenoids

    PubMed Central

    Schaub, Patrick; Rodriguez-Franco, Marta; Cazzonelli, Christopher Ian; Álvarez, Daniel; Wüst, Florian

    2018-01-01

    The net amounts of carotenoids accumulating in plant tissues are determined by the rates of biosynthesis and degradation. While biosynthesis is rate-limited by the activity of PHYTOENE SYNTHASE (PSY), carotenoid losses are caused by catabolic enzymatic and non-enzymatic degradation. We established a system based on non-green Arabidopsis callus which allowed investigating major determinants for high steady-state levels of β-carotene. Wild-type callus development was characterized by strong carotenoid degradation which was only marginally caused by the activity of carotenoid cleavage oxygenases. In contrast, carotenoid degradation occurred mostly non-enzymatically and selectively affected carotenoids in a molecule-dependent manner. Using carotenogenic pathway mutants, we found that linear carotenes such as phytoene, phytofluene and pro-lycopene resisted degradation and accumulated while β-carotene was highly susceptible towards degradation. Moderately increased pathway activity through PSY overexpression was compensated by degradation revealing no net increase in β-carotene. However, higher pathway activities outcompeted carotenoid degradation and efficiently increased steady-state β-carotene amounts to up to 500 μg g-1 dry mass. Furthermore, we identified oxidative β-carotene degradation products which correlated with pathway activities, yielding β-apocarotenals of different chain length and various apocarotene-dialdehydes. The latter included methylglyoxal and glyoxal as putative oxidative end products suggesting a potential recovery of carotenoid-derived carbon for primary metabolic pathways. Moreover, we investigated the site of β-carotene sequestration by co-localization experiments which revealed that β-carotene accumulated as intra-plastid crystals which was confirmed by electron microscopy with carotenoid-accumulating roots. The results are discussed in the context of using the non-green calli carotenoid assay system for approaches targeting high

  12. Trace element accumulation in hawksbill turtles (Eretmochelys imbricata) and green turtles (Chelonia mydas) from Yaeyama Islands, Japan.

    PubMed

    Anan, Y; Kunito, T; Watanabe, I; Sakai, H; Tanabe, S

    2001-12-01

    Concentrations of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Zr, Mo, Ag, Cd, Sb, Ba, Hg, Tl, and Pb) were determined in the liver, kidney, and muscle of green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) from Yaeyama Islands, Okinawa, Japan. Accumulation features of trace elements in the three tissues were similar between green and hawksbill turtles. No gender differences in trace element accumulation in liver and kidney were found for most of the elements. Significant growth-dependent variations were found in concentrations of some elements in tissues of green and hawksbill turtles. Significant negative correlations (p < 0.05) were found between standard carapace length (SCL) and the concentrations of Cu, Zn, and Se in the kidney and V in muscle of green turtles and Mn in the liver, Rb and Ag in kidney, and Hg in muscle of hawksbill turtles. Concentrations of Sr, Mo, Ag, Sb, and Tl in the liver, Sb in kidney, and Sb and Ba in muscle of green turtles and Se and Hg in the liver and Co, Se, and Hg in kidney of hawksbill turtles increased with an increase in SCL (p < 0.05). Green and hawksbill turtles accumulated extremely high concentrations of Cu in the liver and Cd in kidney, whereas the levels of Hg in liver were low in comparison with those of other higher-trophic-level marine animals. High accumulation of Ag in the liver of green turtles was also observed. To evaluate the trophic transfer of trace elements, concentrations of trace elements were determined in stomach contents of green and hawksbill turtles. A remarkably high trophic transfer coefficient was found for Ag and Cd in green turtles and for Cd and Hg in hawksbill turtles.

  13. A feedback mechanism controlling SCRAMBLED receptor accumulation and cell-type pattern in Arabidopsis.

    PubMed

    Kwak, Su-Hwan; Schiefelbein, John

    2008-12-23

    Cellular pattern formation in the root epidermis of Arabidopsis occurs in a position-dependent manner, generating root-hair (H) cells contacting two underlying cortical cells and nonhair (N) cells contacting one cortical cell. SCRAMBLED (SCM), a leucine-rich repeat receptor-like kinase (LRR-RLK), mediates this process through its effect on a downstream transcription factor regulatory network. After perception of a positional cue, the SCM signaling pathway is proposed to preferentially repress WEREWOLF (WER) transcription factor expression in H cells and thereby bias the outcome of mutual lateral inhibition acting between H and N cells. However, the molecular mechanism responsible for this preferential SCM signaling is unknown. Here, we analyze the distribution of the SCM receptor and the biological effect of altering its accumulation pattern. We find that SCM expression and accumulation in the epidermal cell layer is necessary and sufficient to direct the cell-type pattern. Further, SCM preferentially accumulates in H cells, and this accumulation pattern is dependent on the downstream transcription factors. Thus, SCM participates in an autoregulatory feedback loop, enabling cells engaged in SCM signaling to maintain high levels of SCM receptor, which provides a simple mechanism for reinforcing a bias in receptor-mediated signaling to ensure robust pattern formation.

  14. 46 CFR 153.409 - High level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false High level alarms. 153.409 Section 153.409 Shipping... Systems § 153.409 High level alarms. When Table 1 refers to this section or requires a cargo to have a closed gauging system, the cargo's containment system must have a high level alarm: (a) That gives an...

  15. Effect of Hydraulic Accumulator on Pressure Surge of a Hydrostatic Transmission System

    NASA Astrophysics Data System (ADS)

    Kumar, Ajit; Das, Jayanta; Dasgupta, Kabir; Barnwal, Manish Kumar

    2018-04-01

    Hydraulic power system is generally used in off-road vehicles for power transmission such as Heavy Earth Moving Machineries (HEMM). Their energy efficiency and unsubstantial failure becomes an extensive subject of analysis. Various arrangements in the system are compassed along with the utilization of some appropriate components. Application of a hydraulic accumulator is one among them. Benefits of accumulator is its multi-purpose usages like energy saving and pressure surge damping. This paper deals with the control of pressure surges in the hydraulic system and energy saving from the surges by using accumulator. For this purpose, the simulation of the hydraulic system is done in MATLAB/SimulinkR environment and an external disturbance is introduced to generate the pressure surge. The surge absorptivity of the accumulator is studied for different sizes at different pre-charged conditions of the accumulator. The discharge characteristics of different sized accumulators are also analyzed in this paper. It is observed that the ability to absorb the surge and stabilize the system is high in the smaller capacity accumulator. However the energy delivery time of larger sized accumulator is high.

  16. Exercise decreases CLK2 in the liver of obese mice and prevents hepatic fat accumulation.

    PubMed

    Muñoz, Vitor R; Gaspar, Rafael C; Kuga, Gabriel K; Nakandakari, Susana C B R; Baptista, Igor L; Mekary, Rania A; da Silva, Adelino S R; de Moura, Leandro P; Ropelle, Eduardo R; Cintra, Dennys E; Pauli, José R

    2018-03-25

    The accumulation of fatty acids in the liver associated with obesity condition is also known as nonalcoholic fatty liver disease (NAFLD). The impaired fat oxidation in obesity condition leads to increased hepatic fat accumulation and increased metabolic syndrome risk. On the other hand, physical exercise has been demonstrated as a potent strategy in the prevention of NAFLD. Also, these beneficial effects of exercise occur through different mechanisms. Recently, the Cdc2-like kinase (CLK2) protein was associated with the suppression of fatty acid oxidation and hepatic ketogenesis. Thus, obese animals demonstrated elevated levels of hepatic CLK2 and decreased fat acid oxidation. Here, we explored the effects of chronic physical exercise in the hepatic metabolism of obese mice. Swiss mice were distributed in Lean, Obese (fed with high-fat diet during 16 weeks) and Trained Obese group (fed with high-fat diet during 16 weeks and exercised (at 60% exhaustion velocity during 1 h/5 days/week) during 8 weeks. In our results, the obese animals showed insulin resistance, increased hepatic CLK2 content and increased hepatic fat accumulation compared to the Lean group. Otherwise, the chronic physical exercise improved insulin resistance state, prevented the increased CLK2 in the liver and attenuated hepatic fat accumulation. In summary, these data reveal a new protein involved in the prevention of hepatic fat accumulation after chronic physical exercise. More studies can evidence the negative role of CLK2 in the control of liver metabolism, contributing to the improvement of insulin resistance, obesity, and type 2 diabetes. © 2018 Wiley Periodicals, Inc.

  17. Ammonia toxicity induces glutamine accumulation, oxidative stress and immunosuppression in juvenile yellow catfish Pelteobagrus fulvidraco.

    PubMed

    Li, Ming; Gong, Shiyan; Li, Qing; Yuan, Lixia; Meng, Fanxing; Wang, Rixin

    2016-01-01

    A study was carried to test the response of yellow catfish for 28 days under two ammonia concentrations. Weight gain of fish exposure to high and low ammonia abruptly increased at day 3. There were no significant changes in fish physiological indexes and immune responses at different times during 28-day exposure to low ammonia. Fish physiological indexes and immune responses in the treatment of high ammonia were lower than those of fish in the treatment of low ammonia. When fish were exposed to high ammonia, the ammonia concentration in the brain increased by 19-fold on day 1. By comparison, liver ammonia concentration reached its highest level much earlier at hour 12. In spite of a significant increase in brain and liver glutamine concentration, there was no significant change in glutamate level throughout the 28-day period. The total superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) activities in the brain gradually decreased from hour 0 to day 28. Liver SOD, GPX and GR activities reached the highest levels at hour 12, and then gradually decreased. Thiobarbituric acid reactive substance brain and liver content gradually increased throughout the 28-day period. Lysozyme, acid phosphatase and alkaline phosphatase activities in the liver reached exceptionally low levels after day 14. This study indicated that glutamine accumulation in the brain was not the major cause of ammonia poisoning, the toxic reactive oxygen species is not fully counter acted by the antioxidant enzymes and immunosuppression is a process of gradual accumulation of immunosuppressive factors. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Bacterial accumulation in viscosity gradients

    NASA Astrophysics Data System (ADS)

    Waisbord, Nicolas; Guasto, Jeffrey

    2016-11-01

    Cell motility is greatly modified by fluid rheology. In particular, the physical environments in which cells function, are often characterized by gradients of viscous biopolymers, such as mucus and extracellular matrix, which impact processes ranging from reproduction to digestion to biofilm formation. To understand how spatial heterogeneity of fluid rheology affects the motility and transport of swimming cells, we use hydrogel microfluidic devices to generate viscosity gradients in a simple, polymeric, Newtonian fluid. Using video microscopy, we characterize the random walk motility patterns of model bacteria (Bacillus subtilis), showing that both wild-type ('run-and-tumble') cells and smooth-swimming mutants accumulate in the viscous region of the fluid. Through statistical analysis of individual cell trajectories and body kinematics in both homogeneous and heterogeneous viscous environments, we discriminate passive, physical effects from active sensing processes to explain the observed cell accumulation at the ensemble level.

  19. Distribution and accumulation of mercury and copper in mangrove sediments in Shenzhen, the world's most rapid urbanized city.

    PubMed

    Li, Ruili; Xu, Hualin; Chai, Minwei; Qiu, Guo Yu

    2016-02-01

    To investigate the influence of mangrove forest on heavy metal accumulation and storage in intertidal sediments, core sediments from natural mangrove, restored mangrove, and adjacent mud flat spanning the intertidal zone along the south coastline of the most heavily urbanized Deep bay, Guangdong province, China were analyzed. The average concentrations of mercury (Hg) in surface sediments of natural mangrove and restored mangrove were 172 and 151 ng g(-1), whereas those of copper (Cu) were 75 and 50 μg g(-1), respectively. Compared to those from other typical mangrove wetlands of the world, the metal levels in Shenzhen were at median to high levels, which is consistent with the fact that Shenzhen is in high exploitation and its mangrove suffer intensive impact from human activities. Hg and Cu concentration profiles indicated a higher metal accumulation in surface layers of sediments, in agreement with enrichment of organic matter contents. Maximum concentration, enrichment factors, and excess (background-deducted) concentration inventories of metals (Hg and Cu) were substantially different between environments, decreasing from natural mangrove sediments to restored mangrove sediments to mud flat. Furthermore, metal inputs to Futian mangrove decreased in the order natural mangrove > restored mangrove > mud flat, indicating that mangrove facilitated the accumulation and storage of Hg and Cu in sediment layers.

  20. Accumulation of trace metals in sediments in a Mediterranean Lagoon: Usefulness of metal sediment fractionation and elutriate toxicity assessment.

    PubMed

    Zaaboub, Noureddine; Martins, Maria Virgínia Alves; Dhib, Amel; Béjaoui, Béchir; Galgani, François; El Bour, Monia; Aleya, Lotfi

    2015-12-01

    The authors investigated sediment quality in Bizerte Lagoon (Tunisia) focusing on geochemical characteristics, metal sediment fractionation and elutriate toxicity assessment. Nickel, Cu, Zn, Pb, Cr and Cd partitioning in sediments was studied; accumulation and bioavailability were elucidated using enrichment factors, sequential extractions, redox potential, acid volatile sulfide and biotest procedures in toxicity evaluation. Results revealed an accumulation for Pb and Zn, reaching 99 and 460 mg kg(-1) respectively. In addition, the acid volatile sulfide values were high in both eastern and western lagoon areas, thus affecting metal availability. Mean enrichment factor values for Pb and Zn were 4.8 and 4.9, respectively, with these elements as the main contributors to the lagoon's moderate enrichment level. Toxicity levels were influenced by accumulation of Zn in different surface sediment areas. Core sediments were investigated in areas with the highest metal concentrations; metal fractionation and biotest confirmed that Zn contributes to sediment toxicity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Image quality assessment metric for frame accumulated image

    NASA Astrophysics Data System (ADS)

    Yu, Jianping; Li, Gang; Wang, Shaohui; Lin, Ling

    2018-01-01

    The medical image quality determines the accuracy of diagnosis, and the gray-scale resolution is an important parameter to measure image quality. But current objective metrics are not very suitable for assessing medical images obtained by frame accumulation technology. Little attention was paid to the gray-scale resolution, basically based on spatial resolution and limited to the 256 level gray scale of the existing display device. Thus, this paper proposes a metric, "mean signal-to-noise ratio" (MSNR) based on signal-to-noise in order to be more reasonable to evaluate frame accumulated medical image quality. We demonstrate its potential application through a series of images under a constant illumination signal. Here, the mean image of enough images was regarded as the reference image. Several groups of images by different frame accumulation and their MSNR were calculated. The results of the experiment show that, compared with other quality assessment methods, the metric is simpler, more effective, and more suitable for assessing frame accumulated images that surpass the gray scale and precision of the original image.

  2. Constructing the integral concept on the basis of the idea of accumulation: suggestion for a high school curriculum

    NASA Astrophysics Data System (ADS)

    Kouropatov, Anatoli; Dreyfus, Tommy

    2013-07-01

    Students have a tendency to see integral calculus as a series of procedures with associated algorithms and many do not develop a conceptual grasp giving them the desirable versatility of thought. Thus, instead of a proceptual view of the symbols in integration, they have, at best, a process-oriented view. On the other hand, it is not surprising that many students find concepts such as the integral difficult when they are unable to experience these processes directly in the classroom. With a view towards improving this situation, constructing the integral concept on the basis of the idea of accumulation has been proposed (Educ Stud Math. 1994;26:229-274; Integral as accumulation: a didactical perspective for school mathematics; Thessaloniki: PME; 2009. p. 417-424). In this paper, we discuss a curriculum that is based on this idea and a design for curriculum materials that are intended to develop an improved cognitive base for a flexible proceptual understanding of the integral and integration in high school. The main focus is on how we (mathematics teachers and mathematics educators) might teach the integral concept in order to help high school students to construct meaningful knowledge alongside acquiring technical abilities.

  3. High-Level Data-Abstraction System

    NASA Technical Reports Server (NTRS)

    Fishwick, P. A.

    1986-01-01

    Communication with data-base processor flexible and efficient. High Level Data Abstraction (HILDA) system is three-layer system supporting data-abstraction features of Intel data-base processor (DBP). Purpose of HILDA establishment of flexible method of efficiently communicating with DBP. Power of HILDA lies in its extensibility with regard to syntax and semantic changes. HILDA's high-level query language readily modified. Offers powerful potential to computer sites where DBP attached to DEC VAX-series computer. HILDA system written in Pascal and FORTRAN 77 for interactive execution.

  4. Specific accumulation of arsenic compounds in green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) from Ishigaki Island, Japan.

    PubMed

    Agusa, Tetsuro; Takagi, Kozue; Kubota, Reiji; Anan, Yasumi; Iwata, Hisato; Tanabe, Shinsuke

    2008-05-01

    Concentrations of total arsenic (As) and individual compounds were determined in green and hawksbill turtles from Ishigaki Island, Japan. In both species, total As concentrations were highest in muscle among the tissues. Arsenobetaine was a major compound in most tissues of both turtles. High concentrations of trimethylarsine oxide were detected in hawksbill turtles. A significant negative correlation between standard carapace length (SCL), an indicator of age, and total As levels in green turtles was found. In contrast, the levels increased with SCL of hawksbill turtles. Shifts in feeding habitats with growth may account for such a growth-dependent accumulation of As. Although concentrations of As in marine sponges, the major food of hawksbill turtles are not high compared to those in algae eaten by green turtles, As concentrations in hawksbill turtles were higher than those in green turtles, indicating that hawksbill turtles may have a specific accumulation mechanism for As.

  5. Total carbon accumulation in a tropical forest landscape.

    PubMed

    Sierra, Carlos A; Del Valle, Jorge I; Restrepo, Hector I

    2012-12-19

    Regrowing tropical forests worldwide sequester important amounts of carbon and restore part of the C emissions emitted by deforestation. However, there are large uncertainties concerning the rates of carbon accumulation after the abandonment of agricultural and pasture land. We report here accumulation of total carbon stocks (TCS) in a chronosequence of secondary forests at a mid-elevation landscape (900-1200 m asl) in the Andean mountains of Colombia. We found positive accumulation rates for all ecosystem pools except soil carbon, which showed no significant trend of recovery after 36 years of secondary succession. We used these data to develop a simple model to predict accumulation of TCS over time. This model performed remarkably well predicting TCS at other chronosequences in the Americas (Root Mean Square Error < 40 Mg C ha-1), which provided an opportunity to explore different assumptions in the calculation of large-scale carbon budgets. Simulations of TCS with our empirical model were used to test three assumptions often made in carbon budgets: 1) the use of carbon accumulation in tree aboveground biomass as a surrogate for accumulation of TCS, 2) the implicit consideration of carbon legacies from previous land-use, and 3) the omission of landscape age in calculating accumulation rates of TCS. Our simulations showed that in many situations carbon can be released from regrowing secondary forests depending on the amount of carbon legacies and the average age of the landscape. In most cases, the rates used to predict carbon accumulation in the Americas were above the rates predicted in our simulations. These biome level rates seemed to be realistic only in landscapes not affected by carbon legacies from previous land-use and mean ages of around 10 years.

  6. Total carbon accumulation in a tropical forest landscape

    PubMed Central

    2012-01-01

    Background Regrowing tropical forests worldwide sequester important amounts of carbon and restore part of the C emissions emitted by deforestation. However, there are large uncertainties concerning the rates of carbon accumulation after the abandonment of agricultural and pasture land. We report here accumulation of total carbon stocks (TCS) in a chronosequence of secondary forests at a mid-elevation landscape (900-1200 m asl) in the Andean mountains of Colombia. Results We found positive accumulation rates for all ecosystem pools except soil carbon, which showed no significant trend of recovery after 36 years of secondary succession. We used these data to develop a simple model to predict accumulation of TCS over time. This model performed remarkably well predicting TCS at other chronosequences in the Americas (Root Mean Square Error < 40 Mg C ha-1), which provided an opportunity to explore different assumptions in the calculation of large-scale carbon budgets. Simulations of TCS with our empirical model were used to test three assumptions often made in carbon budgets: 1) the use of carbon accumulation in tree aboveground biomass as a surrogate for accumulation of TCS, 2) the implicit consideration of carbon legacies from previous land-use, and 3) the omission of landscape age in calculating accumulation rates of TCS. Conclusions Our simulations showed that in many situations carbon can be released from regrowing secondary forests depending on the amount of carbon legacies and the average age of the landscape. In most cases, the rates used to predict carbon accumulation in the Americas were above the rates predicted in our simulations. These biome level rates seemed to be realistic only in landscapes not affected by carbon legacies from previous land-use and mean ages of around 10 years. PMID:23249727

  7. Adipocyte differentiation-related protein promotes lipid accumulation in goat mammary epithelial cells.

    PubMed

    Shi, H B; Yu, K; Luo, J; Li, J; Tian, H B; Zhu, J J; Sun, Y T; Yao, D W; Xu, H F; Shi, H P; Loor, J J

    2015-10-01

    Milk fat originates from the secretion of cytosolic lipid droplets (CLD) synthesized within mammary epithelial cells. Adipocyte differentiation-related protein (ADRP; gene symbol PLIN2) is a CLD-binding protein that is crucial for synthesis of mature CLD. Our hypothesis was that ADRP regulates CLD production and metabolism in goat mammary epithelial cells (GMEC) and thus plays a role in determining milk fat content. To understand the role of ADRP in ruminant milk fat metabolism, ADRP (PLIN2) was overexpressed or knocked down in GMEC using an adenovirus system. Immunocytochemical staining revealed that ADRP localized to the surface of CLD. Supplementation with oleic acid (OA) enhanced its colocalization with CLD surface and enhanced lipid accumulation. Overexpression of ADRP increased lipid accumulation and the concentration of triacylglycerol in GMEC. In contrast, morphological examination revealed that knockdown of ADRP decreased lipid accumulation even when OA was supplemented. This response was confirmed by the reduction in mass of cellular TG when ADRP was knocked down. The fact that knockdown of ADRP did not completely eliminate lipid accumulation at a morphological level in GMEC without OA suggests that some other compensatory factors may also aid in the process of CLD formation. The ADRP reversed the decrease of CLD accumulation induced by adipose triglyceride lipase. This is highly suggestive of ADRP promoting triacylglycerol stability within CLD by preventing access to adipose triglyceride lipase. Collectively, these data provide direct in vitro evidence that ADRP plays a key role in CLD formation and stability in GMEC. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Dysbiosis of Inferior Turbinate Microbiota Is Associated with High Total IgE Levels in Patients with Allergic Rhinitis.

    PubMed

    Hyun, Dong-Wook; Min, Hyun Jin; Kim, Min-Soo; Whon, Tae Woong; Shin, Na-Ri; Kim, Pil Soo; Kim, Hyun Sik; Lee, June Young; Kang, Woorim; Choi, Augustine M K; Yoon, Joo-Heon; Bae, Jin-Woo

    2018-04-01

    Abnormalities in the human microbiota are associated with the etiology of allergic diseases. Although disease site-specific microbiota may be associated with disease pathophysiology, the role of the nasal microbiota is unclear. We sought to characterize the microbiota of the site of allergic rhinitis, the inferior turbinate, in subjects with allergic rhinitis ( n = 20) and healthy controls ( n = 12) and to examine the relationship of mucosal microbiota with disease occurrence, sensitized allergen number, and allergen-specific and total IgE levels. Microbial dysbiosis correlated significantly with total IgE levels representing combined allergic responses but not with disease occurrence, the number of sensitized allergens, or house dust mite allergen-specific IgE levels. Compared to the populations in individuals with low total IgE levels (group IgE low ), low microbial biodiversity with a high relative abundance of Firmicutes phylum ( Staphylococcus aureus ) and a low relative abundance of Actinobacteria phylum ( Propionibacterium acnes ) was observed in individuals with high total serum IgE levels (group IgE high ). Phylogeny-based microbial functional potential predicted by the 16S rRNA gene indicated an increase in signal transduction-related genes and a decrease in energy metabolism-related genes in group IgE high as shown in the microbial features with atopic and/or inflammatory diseases. Thus, dysbiosis of the inferior turbinate mucosa microbiota, particularly an increase in S. aureus and a decrease in P. acnes , is linked to high total IgE levels in allergic rhinitis, suggesting that inferior turbinate microbiota may be affected by accumulated allergic responses against sensitized allergens and that site-specific microbial alterations play a potential role in disease pathophysiology. Copyright © 2018 American Society for Microbiology.

  9. Effects of perchlorate on growth of four wetland plants and its accumulation in plant tissues.

    PubMed

    He, Hongzhi; Gao, Haishuo; Chen, Guikui; Li, Huashou; Lin, Hai; Shu, Zhenzhen

    2013-10-01

    Perchlorate contamination in water is of concern because of uncertainties about toxicity and health effects, impact on ecosystems, and possible indirect exposure pathways to humans. Therefore, it is very important to investigate the ecotoxicology of perchlorate and to screen plant species for phytoremediation. Effects of perchlorate (20, 200, and 500 mg/L) on the growth of four wetland plants (Eichhornia crassipes, Acorus calamus L., Thalia dealbata, and Canna indica) as well as its accumulation in different plant tissues were investigated through water culture experiments. Twenty milligrams per liter of perchlorate had no significant effects on height, root length, aboveground part weight, root weight, and oxidizing power of roots of four plants, except A. calamus, and increasing concentrations of perchlorate showed that out of the four wetland plants, only A. calamus had a significant (p<0.05) dose-dependent decrease in these parameters. When treated with 500 mg/L perchlorate, these parameters and chlorophyll content in the leaf of plants showed significant decline contrasted to control groups, except the root length of E. crassipes and C. indica. The order of inhibition rates of perchlorate on root length, aboveground part weight and root weight, and oxidizing power of roots was: A. calamus > C. indica > T. dealbata > E. crassipes and on chlorophyll content in the leaf it was: A. calamus > T. dealbata > C. indica > E. crassipes. The higher the concentration of perchlorate used, the higher the amount of perchlorate accumulation in plants. Perchlorate accumulation in aboveground tissues was much higher than that in underground tissues and leaf was the main tissue for perchlorate accumulation. The order of perchlorate accumulation content and the bioconcentration factor in leaf of four plants was: E. crassipes > C. indica > T. dealbata > A. calamus. Therefore, E. crassipes might be an ideal plant with high tolerance ability and accumulation ability for constructing

  10. Dual mechanisms regulating glutamate decarboxylases and accumulation of gamma-aminobutyric acid in tea (Camellia sinensis) leaves exposed to multiple stresses

    PubMed Central

    Mei, Xin; Chen, Yiyong; Zhang, Lingyun; Fu, Xiumin; Wei, Qing; Grierson, Don; Zhou, Ying; Huang, Yahui; Dong, Fang; Yang, Ziyin

    2016-01-01

    γ-Aminobutyric acid (GABA) is one of the major inhibitory neurotransmitters in the central nervous system. It has multiple positive effects on mammalian physiology and is an important bioactive component of tea (Camellia sinensis). GABA generally occurs at a very low level in plants but GABA content increases substantially after exposure to a range of stresses, especially oxygen-deficiency. During processing of tea leaves, a combination of anoxic stress and mechanical damage are essential for the high accumulation of GABA. This is believed to be initiated by a change in glutamate decarboxylase activity, but the underlying mechanisms are unclear. In the present study we characterized factors regulating the expression and activity of three tea glutamate decarboxylase genes (CsGAD1, 2, and 3), and their encoded enzymes. The results suggests that, unlike the model plant Arabidopsis thaliana, there are dual mechanisms regulating the accumulation of GABA in tea leaves exposed to multiple stresses, including activation of CsGAD1 enzymatic activity by calmodulin upon the onset of the stress and accumulation of high levels of CsGAD2 mRNA induced by a combination of anoxic stress and mechanical damage. PMID:27021285

  11. Dual mechanisms regulating glutamate decarboxylases and accumulation of gamma-aminobutyric acid in tea (Camellia sinensis) leaves exposed to multiple stresses.

    PubMed

    Mei, Xin; Chen, Yiyong; Zhang, Lingyun; Fu, Xiumin; Wei, Qing; Grierson, Don; Zhou, Ying; Huang, Yahui; Dong, Fang; Yang, Ziyin

    2016-03-29

    γ-Aminobutyric acid (GABA) is one of the major inhibitory neurotransmitters in the central nervous system. It has multiple positive effects on mammalian physiology and is an important bioactive component of tea (Camellia sinensis). GABA generally occurs at a very low level in plants but GABA content increases substantially after exposure to a range of stresses, especially oxygen-deficiency. During processing of tea leaves, a combination of anoxic stress and mechanical damage are essential for the high accumulation of GABA. This is believed to be initiated by a change in glutamate decarboxylase activity, but the underlying mechanisms are unclear. In the present study we characterized factors regulating the expression and activity of three tea glutamate decarboxylase genes (CsGAD1, 2, and 3), and their encoded enzymes. The results suggests that, unlike the model plant Arabidopsis thaliana, there are dual mechanisms regulating the accumulation of GABA in tea leaves exposed to multiple stresses, including activation of CsGAD1 enzymatic activity by calmodulin upon the onset of the stress and accumulation of high levels of CsGAD2 mRNA induced by a combination of anoxic stress and mechanical damage.

  12. Enhanced decomposition offsets enhanced productivity and soil carbon accumulation in coastal wetlands responding to climate change

    USGS Publications Warehouse

    Kirwan, M.L.; Blum, L.K.

    2011-01-01

    Coastal wetlands are responsible for about half of all carbon burial in oceans, and their persistence as a valuable ecosystem depends largely on the ability to accumulate organic material at rates equivalent to relative sea level rise. Recent work suggests that elevated CO2 and temperature warming will increase organic matter productivity and the ability of marshes to survive sea level rise. However, we find that organic decomposition rates increase by about 12% per degree of warming. Our measured temperature sensitivity is similar to studies from terrestrial systems, twice as high as the response of salt marsh productivity to temperature warming, and roughly equivalent to the productivity response associated with elevated CO2 in C3 marsh plants. Therefore, enhanced CO2 and warmer temperatures may actually make marshes less resilient to sea level rise, and tend to promote a release of soil carbon. Simple projections indicate that elevated temperatures will increase rates of sea level rise more than any acceleration in organic matter accumulation, suggesting the possibility of a positive feedback between climate, sea level rise, and carbon emissions in coastal environments. ?? 2011 Author(s).

  13. Crystallization in high-level waste glass: A review of glass theory and noteworthy literature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Christian, J. H.

    2015-08-01

    There is a fundamental need to continue research aimed at understanding nepheline and spinel crystal formation in high-level waste (HLW) glass. Specifically, the formation of nepheline solids (K/NaAlSiO₄) during slow cooling of HLW glass can reduce the chemical durability of the glass, which can cause a decrease in the overall durability of the glass waste form. The accumulation of spinel solids ((Fe, Ni, Mn, Zn)(Fe,Cr)₂O₄), while not detrimental to glass durability, can cause an array of processing problems inside of HLW glass melters. In this review, the fundamental differences between glass and solid-crystals are explained using kinetic, thermodynamic, and viscositymore » arguments, and several highlights of glass-crystallization research, as it pertains to high-level waste vitrification, are described. In terms of mitigating spinel in the melter and both spinel and nepheline formation in the canister, the complexity of HLW glass and the intricate interplay between thermal, chemical, and kinetic factors further complicates this understanding. However, new experiments seeking to elucidate the contributing factors of crystal nucleation and growth in waste glass, and the compilation of data from older experiments, may go a long way towards helping to achieve higher waste loadings while developing more efficient processing strategies.« less

  14. Annual Greenland Accumulation Rates (2009-2012) from Airborne Snow Radar

    NASA Technical Reports Server (NTRS)

    Koenig, Lora S.; Ivanoff, Alvaro; Alexander, Patrick M.; MacGregor, Joseph A.; Fettweis, Xavier; Panzer, Ben; Paden, John D.; Forster, Richard R.; Das, Indrani; McConnell, Joseph R.; hide

    2016-01-01

    Contemporary climate warming over the Arctic is accelerating mass loss from the Greenland Ice Sheet through increasing surface melt, emphasizing the need to closely monitor its surface mass balance in order to improve sea-level rise predictions. Snow accumulation is the largest component of the ice sheet's surface mass balance, but in situ observations thereof are inherently sparse and models are difficult to evaluate at large scales. Here, we quantify recent Greenland accumulation rates using ultra-wideband (2-6.5 gigahertz) airborne snow radar data collected as part of NASA's Operation IceBridge between 2009 and 2012. We use a semi-automated method to trace the observed radiostratigraphy and then derive annual net accumulation rates for 2009-2012. The uncertainty in these radar-derived accumulation rates is on average 14 percent. A comparison of the radarderived accumulation rates and contemporaneous ice cores shows that snow radar captures both the annual and longterm mean accumulation rate accurately. A comparison with outputs from a regional climate model (MAR - Modele Atmospherique Regional for Greenland and vicinity) shows that this model matches radar-derived accumulation rates in the ice sheet interior but produces higher values over southeastern Greenland. Our results demonstrate that snow radar can efficiently and accurately map patterns of snow accumulation across an ice sheet and that it is valuable for evaluating the accuracy of surface mass balance models.

  15. Soil nitrate accumulation dominates the nonlinear responses of soil CO2 and CH4 fluxes to multi-level nitrogen addition in a temperate needle-broadleaved mixed forest

    NASA Astrophysics Data System (ADS)

    Fang, Huajun

    2017-04-01

    The responses of soil-atmosphere carbon (C) exchange fluxes to increased atmospheric nitrogen (N) deposition are controversial, leading to great uncertainty in the evaluation on the C sink capacity of global forest ecosystems elicited by anthropogenic N inputs. To date, we hardly knew how much was the critical level of N input for the alteration of the soil C fluxes, and what factors controlled the changes in soil CO2 and CH4 fluxes under N enrichment. Nine levels of urea addition experiment (0, 10, 20, 40, 60, 80, 100, 120, 140 kg N ha-1 yr-1) was conducted in the needle-broadleaved mixed forest in Changbai Mountain, Northeast China. Soil CO2 and CH4 fluxes were monitored weekly using the static chamber and gas chromatograph technique. Environmental variables (soil temperature and moisture in the 0-10 cm depth) and dissolved N (NH4+-N, NO3-N, total dissolved N (TDN), and dissolved organic N (DON)) in the organic layer and the 0-10 cm mineral soil layer were simultaneously measured. High rates of N addition (≥ 60 kg N ha-1 yr-1) significantly increased soil NO3-N contents in the organic layer and the mineral layer by 120%-180% and 56.4%-84.6%, respectively. However, N application did not lead to a significant accumulation of soil NH4+-N contents in the two soil layers except for a few treatments. N addition at a low rate of 10 kg N ha-1 yr-1 significantly promoted soil CO2 emission and CH4 uptake, whereas high rate of N addition (140 kg N ha-1 yr-1) significantly inhibited them. Significant negative relationships were observed between changes in soil CO2 emission and CH4 uptake and changes in soil NO3-N and moisture contents under N enrichment. These results suggest that soil nitrification and NO3-N accumulation could be important regulators of soil CO2 emission and CH4 uptake in the temperate needle-broadleaved mixed forest. The nonlinear responses to exogenous N inputs and the critical levels for the alteration of soil C fluxes should be considered in the

  16. Temperature-dependence of biomass accumulation rates during secondary succession.

    PubMed

    Anderson, Kristina J; Allen, Andrew P; Gillooly, James F; Brown, James H

    2006-06-01

    Rates of ecosystem recovery following disturbance affect many ecological processes, including carbon cycling in the biosphere. Here, we present a model that predicts the temperature dependence of the biomass accumulation rate following disturbances in forests. Model predictions are derived based on allometric and biochemical principles that govern plant energetics and are tested using a global database of 91 studies of secondary succession compiled from the literature. The rate of biomass accumulation during secondary succession increases with average growing season temperature as predicted based on the biochemical kinetics of photosynthesis in chloroplasts. In addition, the rate of biomass accumulation is greater in angiosperm-dominated communities than in gymnosperm-dominated ones and greater in plantations than in naturally regenerating stands. By linking the temperature-dependence of photosynthesis to the rate of whole-ecosystem biomass accumulation during secondary succession, our model and results provide one example of how emergent, ecosystem-level rate processes can be predicted based on the kinetics of individual metabolic rate.

  17. Highly elevated atmospheric levels of volatile organic compounds in the Uintah Basin, Utah.

    PubMed

    Helmig, D; Thompson, C R; Evans, J; Boylan, P; Hueber, J; Park, J-H

    2014-05-06

    Oil and natural gas production in the Western United States has grown rapidly in recent years, and with this industrial expansion, growing environmental concerns have arisen regarding impacts on water supplies and air quality. Recent studies have revealed highly enhanced atmospheric levels of volatile organic compounds (VOCs) from primary emissions in regions of heavy oil and gas development and associated rapid photochemical production of ozone during winter. Here, we present surface and vertical profile observations of VOC from the Uintah Basin Winter Ozone Studies conducted in January-February of 2012 and 2013. These measurements identify highly elevated levels of atmospheric alkane hydrocarbons with enhanced rates of C2-C5 nonmethane hydrocarbon (NMHC) mean mole fractions during temperature inversion events in 2013 at 200-300 times above the regional and seasonal background. Elevated atmospheric NMHC mole fractions coincided with build-up of ambient 1-h ozone to levels exceeding 150 ppbv (parts per billion by volume). The total annual mass flux of C2-C7 VOC was estimated at 194 ± 56 × 10(6) kg yr(-1), equivalent to the annual VOC emissions of a fleet of ∼100 million automobiles. Total annual fugitive emission of the aromatic compounds benzene and toluene, considered air toxics, were estimated at 1.6 ± 0.4 × 10(6) and 2.0 ± 0.5 × 10(6) kg yr(-1), respectively. These observations reveal a strong causal link between oil and gas emissions, accumulation of air toxics, and significant production of ozone in the atmospheric surface layer.

  18. Dietary Betaine Supplementation Increases Fgf21 Levels to Improve Glucose Homeostasis and Reduce Hepatic Lipid Accumulation in Mice.

    PubMed

    Ejaz, Asma; Martinez-Guino, Laura; Goldfine, Allison B; Ribas-Aulinas, Francesc; De Nigris, Valeria; Ribó, Sílvia; Gonzalez-Franquesa, Alba; Garcia-Roves, Pablo M; Li, Elizabeth; Dreyfuss, Jonathan M; Gall, Walt; Kim, Jason K; Bottiglieri, Teodoro; Villarroya, Francesc; Gerszten, Robert E; Patti, Mary-Elizabeth; Lerin, Carles

    2016-04-01

    Identifying markers of human insulin resistance may permit development of new approaches for treatment and prevention of type 2 diabetes. To this end, we analyzed the fasting plasma metabolome in metabolically characterized human volunteers across a spectrum of insulin resistance. We demonstrate that plasma betaine levels are reduced in insulin-resistant humans and correlate closely with insulin sensitivity. Moreover, betaine administration to mice with diet-induced obesity prevents the development of impaired glucose homeostasis, reduces hepatic lipid accumulation, increases white adipose oxidative capacity, and enhances whole-body energy expenditure. In parallel with these beneficial metabolic effects, betaine supplementation robustly increased hepatic and circulating fibroblast growth factor (Fgf)21 levels. Betaine administration failed to improve glucose homeostasis and liver fat content in Fgf21(-/-) mice, demonstrating that Fgf21 is necessary for betaine's beneficial effects. Together, these data indicate that dietary betaine increases Fgf21 levels to improve metabolic health in mice and suggest that betaine supplementation merits further investigation as a supplement for treatment or prevention of type 2 diabetes in humans. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  19. Ferulic acid lowers body weight and visceral fat accumulation via modulation of enzymatic, hormonal and inflammatory changes in a mouse model of high-fat diet-induced obesity

    PubMed Central

    de Melo, T.S.; Lima, P.R.; Carvalho, K.M.M.B.; Fontenele, T.M.; Solon, F.R.N.; Tomé, A.R.; de Lemos, T.L.G.; da Cruz Fonseca, S.G.; Santos, F.A.; Rao, V.S.; de Queiroz, M.G.R.

    2017-01-01

    Previous studies have reported on the glucose and lipid-lowering effects of ferulic acid (FA) but its anti-obesity potential has not yet been firmly established. This study investigated the possible anti-obesitogenic effects of FA in mice fed a high-fat diet (HFD) for 15 weeks. To assess the antiobesity potential of FA, 32 male Swiss mice, weighing 20–25 g (n=6–8 per group) were fed a normal diet (ND) or HFD, treated orally or not with either FA (10 mg/kg) or sibutramine (10 mg/kg) for 15 weeks and at the end of this period, the body weights of animals, visceral fat accumulation, plasma levels of glucose and insulin hormone, amylase and lipase activities, the satiety hormones ghrelin and leptin, and tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCH-1) were analyzed. Results revealed that FA could effectively suppress the HFD-associated increase in visceral fat accumulation, adipocyte size and body weight gain, similar to sibutramine, the positive control. FA also significantly (P<0.05) decreased the HFD-induced elevations in serum lipid profiles, amylase and lipase activities, and the levels of blood glucose and insulin hormone. The markedly elevated leptin and decreased ghrelin levels seen in HFD-fed control mice were significantly (P<0.05) reversed by FA treatment, almost reaching the values seen in ND-fed mice. Furthermore, FA demonstrated significant (P<0.05) inhibition of serum levels of inflammatory mediators TNF-α, and MCH-1. These results suggest that FA could be beneficial in lowering the risk of HFD-induced obesity via modulation of enzymatic, hormonal and inflammatory responses. PMID:28076453

  20. Ferulic acid lowers body weight and visceral fat accumulation via modulation of enzymatic, hormonal and inflammatory changes in a mouse model of high-fat diet-induced obesity.

    PubMed

    de Melo, T S; Lima, P R; Carvalho, K M M B; Fontenele, T M; Solon, F R N; Tomé, A R; de Lemos, T L G; da Cruz Fonseca, S G; Santos, F A; Rao, V S; de Queiroz, M G R

    2017-01-05

    Previous studies have reported on the glucose and lipid-lowering effects of ferulic acid (FA) but its anti-obesity potential has not yet been firmly established. This study investigated the possible anti-obesitogenic effects of FA in mice fed a high-fat diet (HFD) for 15 weeks. To assess the antiobesity potential of FA, 32 male Swiss mice, weighing 20-25 g (n=6-8 per group) were fed a normal diet (ND) or HFD, treated orally or not with either FA (10 mg/kg) or sibutramine (10 mg/kg) for 15 weeks and at the end of this period, the body weights of animals, visceral fat accumulation, plasma levels of glucose and insulin hormone, amylase and lipase activities, the satiety hormones ghrelin and leptin, and tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCH-1) were analyzed. Results revealed that FA could effectively suppress the HFD-associated increase in visceral fat accumulation, adipocyte size and body weight gain, similar to sibutramine, the positive control. FA also significantly (P<0.05) decreased the HFD-induced elevations in serum lipid profiles, amylase and lipase activities, and the levels of blood glucose and insulin hormone. The markedly elevated leptin and decreased ghrelin levels seen in HFD-fed control mice were significantly (P<0.05) reversed by FA treatment, almost reaching the values seen in ND-fed mice. Furthermore, FA demonstrated significant (P<0.05) inhibition of serum levels of inflammatory mediators TNF-α, and MCH-1. These results suggest that FA could be beneficial in lowering the risk of HFD-induced obesity via modulation of enzymatic, hormonal and inflammatory responses.

  1. Nutrient and Antinutrient Compositions and Heavy Metal Uptake and Accumulation in S. nigrum Cultivated on Different Soil Types

    PubMed Central

    Ogundola, Adijat Funke; Bvenura, Callistus

    2018-01-01

    Solanum nigrum cultivated on different soil texture types, sandy clay loam, silty clay loam, clay loam, loam, and control soils, were evaluated for proximate compositions, antinutrients, vitamins, and mineral composition with plant age using standard analytical methods. Accumulation of trace elements using translocation factor was studied to determine their toxic levels in plant tissues. Data were analysed by ANOVA and results expressed as means and standard deviation. Ash content, crude fibre, protein, alkaloid, phytate, and saponin ranged between 11.4 and 12%, 19.24 and 19.95%, 34.23 and 38.98, 42.08 and 45.76 mg/ml, 0.84 and 1.17%, and 94.10 and 97.00%, respectively. Vitamins A, C, and B were present in high quantity. Macro- and micronutrients recorded showed that S. nigrum is a potential reservoir of minerals. Accumulation of micronutrients was observed to be the highest at the flowering stage between the 4th and 5th weeks after transplanting. Plants cultivated on clay loam, silty clay loam, and loam soils accumulated elevated nutritional compositions and abundant antinutrients. However, the accumulated trace metals in the plants are within the recommended safe levels. All nutrient values are in the recommended requirements for daily consumption. PMID:29576752

  2. Lipid accumulation in smooth muscle cells under LDL loading is independent of LDL receptor pathway and enhanced by hypoxic conditions.

    PubMed

    Wada, Youichiro; Sugiyama, Akira; Yamamoto, Takashi; Naito, Makoto; Noguchi, Noriko; Yokoyama, Shinji; Tsujita, Maki; Kawabe, Yoshiki; Kobayashi, Mika; Izumi, Akashi; Kohro, Takahide; Tanaka, Toshiya; Taniguchi, Hirokazu; Koyama, Hidenori; Hirano, Ken-ichi; Yamashita, Shizuya; Matsuzawa, Yuji; Niki, Etsuo; Hamakubo, Takao; Kodama, Tatsuhiko

    2002-10-01

    The effect of a variety of hypoxic conditions on lipid accumulation in smooth muscle cells (SMCs) was studied in an arterial wall coculture and monocultivation model. Low density lipoprotein (LDL) was loaded under various levels of oxygen tension. Oil red O staining of rabbit and human SMCs revealed that lipid accumulation was greater under lower oxygen tension. Cholesterol esters were shown to accumulate in an oxygen tension-dependent manner by high-performance liquid chromatographic analysis. Autoradiograms using radiolabeled LDL indicated that LDL uptake was more pronounced under hypoxia. This result holds in the case of LDL receptor-deficient rabbit SMCs. However, cholesterol biosynthesis and cellular cholesterol release were unaffected by oxygen tension. Hypoxia significantly increases LDL uptake and enhances lipid accumulation in arterial SMCs, exclusive of LDL receptor activity. Although the molecular mechanism is not clear, the model is useful for studying lipid accumulation in arterial wall cells and the difficult-to-elucidate events in the initial stage of atherogenesis.

  3. Mechanisms of intrahepatic triglyceride accumulation

    PubMed Central

    Ress, Claudia; Kaser, Susanne

    2016-01-01

    Hepatic steatosis defined as lipid accumulation in hepatocytes is very frequently found in adults and obese adolescents in the Western World. Etiologically, obesity and associated insulin resistance or excess alcohol intake are the most frequent causes of hepatic steatosis. However, steatosis also often occurs with chronic hepatitis C virus (HCV) infection and is also found in rare but potentially life-threatening liver diseases of pregnancy. Clinical significance and outcome of hepatic triglyceride accumulation are highly dependent on etiology and histological pattern of steatosis. This review summarizes current concepts of pathophysiology of common causes of hepatic steatosis, including non-alcoholic fatty liver disease (NAFLD), alcoholic fatty liver disease, chronic HCV infections, drug-induced forms of hepatic steatosis, and acute fatty liver of pregnancy. Regarding the pathophysiology of NAFLD, this work focuses on the close correlation between insulin resistance and hepatic triglyceride accumulation, highlighting the potential harmful effects of systemic insulin resistance on hepatic metabolism of fatty acids on the one side and the role of lipid intermediates on insulin signalling on the other side. Current studies on lipid droplet morphogenesis have identified novel candidate proteins and enzymes in NAFLD. PMID:26819531

  4. Amyloid β1-43 Accumulates in the Lens Epithelium of Cortical Opacification in Japanese Patients.

    PubMed

    Nagai, Noriaki; Mano, Yu; Otake, Hiroko; Shibata, Teppei; Kubo, Eri; Sasaki, Hiroshi

    2017-06-01

    We investigated the accumulation of amyloid β (Aβ1-40, Aβ1-42, Aβ1-43) in the lens epithelium of patients with opacification of five different types (cortical cataract [COR]; nuclear cataract [NUC]; posterior subcapsular cataract [PSC]; retrodots [RD]; and water clefts [WC]). Samples were collected from Japanese patients taken during cataract surgery; Aβ levels and mRNA expression were determined by ELISA and a real-time RT-PCR method, respectively. Levels of Aβ1-40 and Aβ1-42 in the lens epithelium of patients with COR, NUC, PSC, RD, and WC showed no significant differences in comparison with transparent lens epithelium. Levels of Aβ1-43 in the lens epithelium of patients with PSC and WC were not detected, and NUC and RD were slightly elevated. In contrast to the results in these cataract types, high Aβ1-43 levels were observed in the lens epithelium of patients with COR, and a close relationship was observed between Aβ1-43 levels and the degree of lens opacification (R = 0.8229, n = 6). The levels of Aβ1-43 were also higher in the lens epithelium of patients with mixed-cataract showing cortical opacification, and the Aβ1-43 levels in the lens epithelium of mixed-cataract patients with cortical opacification was significantly higher than in that of mixed-cataract patients without cortical opacification. In addition, the level of an amyloid precursor protein mRNA in the lens epithelium of mixed-cataract patients with cortical opacification was significantly higher than in transparent lens and mixed-cataract patients without cortical opacification. We found high levels of Aβ1-43 accumulation in the lens epithelium of Japanese patients with cortical opacification.

  5. Engineering the bacterial shapes for enhanced inclusion bodies accumulation.

    PubMed

    Jiang, Xiao-Ran; Wang, Huan; Shen, Rui; Chen, Guo-Qiang

    2015-05-01

    Many bacteria can accumulate inclusion bodies such as sulfur, polyphosphate, glycogen, proteins or polyhydroxyalkanoates. To exploit bacteria as factories for effective production of inclusion bodies, a larger intracellular space is needed for more inclusion body accumulation. In this study, polyhydroxybutyrate (PHB) was investigated as an inclusion bodies representative to be accumulated by Escherichia coli JM109SG. Various approaches were taken to increase the bacterial cell sizes including deletion on actin-like protein gene mreB, weak expression of mreB in mreB deletion mutant, and weak expression of mreB in mreB deletion mutant under inducible expression of SulA, the inhibitor of division ring protein FtsZ. All of the methods resulted in different levels of increases in bacterial sizes and PHB granules accumulation. Remarkably, an increase of over 100% PHB accumulation was observed in recombinant E. coli overexpressing mreB in an mreB deletion mutant under inducible expression of FtsZ inhibiting protein SulA. The molecular mechanism of enlarged bacterial size was found to be directly relate to weakened cytoskeleton which was the result of broken skeleton helix. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  6. Engineering α-amylase levels in wheat grain suggests a highly sophisticated level of carbohydrate regulation during development

    PubMed Central

    Whan, Alex; Dielen, Anne-Sophie; Mieog, Jos; Bowerman, Andrew F.; Robinson, Hannah M.; Byrne, Keren; Colgrave, Michelle; Larkin, Philip J.; Howitt, Crispin A.; Morell, Matthew K.; Ral, Jean-Philippe

    2014-01-01

    Wheat starch degradation requires the synergistic action of different amylolytic enzymes. Our spatio-temporal study of wheat α-amylases throughout grain development shows that AMY3 is the most abundant isoform compared with the other known α-amylases. Endosperm-specific over-expression of AMY3 resulted in an increase of total α-amylase activity in harvested grains. Unexpectedly, increased activity did not have a significant impact on starch content or composition but led to an increase of soluble carbohydrate (mainly sucrose) in dry grain. In AMY3 overexpression lines (A3OE), germination was slightly delayed and triacylglycerol (TAG) content was increased in the endosperm of mature grain. Despite increased AMY3 transcript and protein content throughout grain development, alterations of α-amylase activity and starch granule degradation were not detected until grain maturation, suggesting a post-translational inhibition of α-amylase activity in the endosperm during the starch filling period. These findings show unexpected effects of a high level of α-amylase on grain development and composition, notably in carbon partitioning and TAG accumulation, and suggest the presence of a hitherto unknown regulatory pathway during grain filling. PMID:25053646

  7. Network-based high level data classification.

    PubMed

    Silva, Thiago Christiano; Zhao, Liang

    2012-06-01

    Traditional supervised data classification considers only physical features (e.g., distance or similarity) of the input data. Here, this type of learning is called low level classification. On the other hand, the human (animal) brain performs both low and high orders of learning and it has facility in identifying patterns according to the semantic meaning of the input data. Data classification that considers not only physical attributes but also the pattern formation is, here, referred to as high level classification. In this paper, we propose a hybrid classification technique that combines both types of learning. The low level term can be implemented by any classification technique, while the high level term is realized by the extraction of features of the underlying network constructed from the input data. Thus, the former classifies the test instances by their physical features or class topologies, while the latter measures the compliance of the test instances to the pattern formation of the data. Our study shows that the proposed technique not only can realize classification according to the pattern formation, but also is able to improve the performance of traditional classification techniques. Furthermore, as the class configuration's complexity increases, such as the mixture among different classes, a larger portion of the high level term is required to get correct classification. This feature confirms that the high level classification has a special importance in complex situations of classification. Finally, we show how the proposed technique can be employed in a real-world application, where it is capable of identifying variations and distortions of handwritten digit images. As a result, it supplies an improvement in the overall pattern recognition rate.

  8. High residue levels and the chemical form of mercury in tissues and organs of seabirds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, E.Y.; Murakami, Toru; Saeki, Kazutoshi

    1995-12-31

    Total and organic (methyl) mercury in liver, muscle, kidney and feather of 9 species of seabirds were analyzed to determine the levels and their distribution and to clarify the occurrences of high mercury levels and their detoxification process in seabirds. Total mercury levels in liver showed great variations in intra and interspecies, while organic mercury levels were less variable. As compared with species in relatively low mercury levels, the species which accumulated the high concentration of mercury like black-footed albatross exhibited the different distribution of mercury in the body: in total mercury burden, albatross species contained less than 10% inmore » feather and over 50% in liver, while other species contained over 40% in feather and less than 20% in liver. The order of organic mercury concentrations in tissues were as follows: liver > kidney > muscle in seabirds examined, except oldsquaw. The mean percentage of organic mercury in total was 35%, 66%, and 36% in liver, muscle and kidney, respectively, for all the species. The significant negative correlations were found between organic mercury percentage to total mercury and total mercury concentrations in the liver and muscle of black-footed albatross and in the liver of laysan albatross. Furthermore, in liver, muscle, and kidney of all the species, the percentages of organic mercury had a negative trend with an increase of total mercury concentrations. The results suggest that albatross species may be capable for demethylating organic mercury in the tissues (mainly in liver), and for storing the mercury as immobilizable inorganic form in the liver as substitution for delivering organic mercury to other organs. It is noteworthy that the species with high degree of demethylation showed the lower mercury burdens in feather and slow moulting pattern.« less

  9. Environmental parasitology: Parasites as accumulation bioindicators in the marine environment

    NASA Astrophysics Data System (ADS)

    Nachev, Milen; Sures, Bernd

    2016-07-01

    Parasites can be used as effective monitoring tools in environmental impact studies as they are able to accumulate certain pollutants (e.g. metals) at levels much higher than those of their ambient environment and of free-living sentinels. Thus, they provide valuable information not only about the chemical conditions of their and their hosts' environment but also deliver insights into the biological availability of allochthonous substances. While a large number of different freshwater parasites (mainly acanthocephalans and cestodes) were investigated in terms of pollutant bioaccumulation, studies based on marine host-parasites systems remain scarce. However, available data show that different marine parasite taxa such as nematodes, cestodes and acanthocephalans exhibit also an excellent metal accumulation capacity. The biological availability of metals and their uptake routes in marine biota and parasites differ from those of freshwater organisms. We assume that a large part of metals and other pollutants are also taken up via the digestive system of the host. Therefore, in addition to environmental conditions the physiology of the host also plays an important role for the accumulation process. Additionally, we highlight some advantages in using parasites as accumulation indicators in marine ecosystems. As parasites occur ubiquitously in marine food webs, the monitoring of metals in their tissues can deliver information about the spatial and trophic distribution of pollutants. Accordingly, parasites as indicators offer an ecological assessment on a broader scale, in contrast to established free-living marine indicators, which are mostly benthic invertebrates and therefore limited in habitat distribution. Globally distributed parasite taxa, which are highly abundant in a large number of host species, are suggested as worldwide applicable sentinels.

  10. Nickel accumulation and its effect on growth, physiological and biochemical parameters in millets and oats.

    PubMed

    Gupta, Vibha; Jatav, Pradeep Kumar; Verma, Raini; Kothari, Shanker Lal; Kachhwaha, Sumita

    2017-10-01

    With the boom in industrialization, there is an increase in the level of heavy metals in the soil which drastically affect the growth and development of plants. Nickel is an essential micronutrient for plant growth and development, but elevated level of Ni causes stunted growth, chlorosis, nutrient imbalance, and alterations in the defense mechanism of plants in terms of accumulation of osmolytes or change in enzyme activities like guiacol peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Ni-induced toxic response was studied in seedlings of finger millet, pearl millet, and oats in terms of seedling growth, lipid peroxidation, total chlorophyll, proline content, and enzymatic activities. On the basis of germination and growth parameters of the seedling, finger millet was found to be the most tolerant. Nickel accumulation was markedly lower in the shoots as compared to the roots, which was the highest in finger millet and the lowest in shoots of oats. Plants treated with a high concentration of Ni showed significant reduction in chlorophyll and increase in proline content. Considerable difference in level of malondialdehyde (MDA) content and activity of antioxidative enzymes indicates generation of redox imbalance in plants due to Ni-induced stress. Elevated activities of POD and SOD were observed with high concentrations of Ni while CAT activity was found to be reduced. It was observed that finger millet has higher capability to maintain homeostasis by keeping the balance between accumulation and ROS scavenging system than pearl millet and oats. The data provide insight into the physiological and biochemical changes in plants adapted to survive in Ni-rich environment. This study will help in selecting the more suitable crop species to be grown on Ni-rich soils.

  11. [CaCO3 stimulates alpha-ketoglutarate accumulation during pyruvate fermentation by Torulopsis glabrata].

    PubMed

    Liu, Li-Ming; Li, Yin; Du, Guo-Cheng; Chen, Jian

    2003-11-01

    A large amount of alpha-ketoglutarate (alpha-KG) (6.8 g/L) was accumulated in flask culture when CaCO3 was used as a buffering agent in the production of pyruvate by multi-vitamin auxotrophic yeast Torulopsis glabrata CCTCC M202019. In a 5 L jar-fermentor, less alpha-KG (1.3 g/L) was produced when NaOH was used to adjust the pH, while more alpha-KG (11.5 g/L) detected when CaCO3 was used as the buffer. In the latter case, the molar carbon ratio of pyruvate to alpha-KG (C(PYR)/ CalphaKG) was similar to that obtained in flask culture, suggesting the accumulation of alpha-ketoglutarate was related to the addition of CaCO3. Furthermore, it was found that: (1) delaying the addition time of CaCO3 decreased the a-ketoglutarate formation but increased C(PYR)/ C(alphaKG); and (2) under vitamin limitation conditions increasing the concentration of CaCO3 led to an increased a-KG accumulation at the expenses of pyruvate. To study which ions in CaCO3 was responsible for the accumulation of alpha-KG, the effects of different pH buffers on the a-KG accumulation were studied. The level of alpha-KG was found to correlate with the levels of both Ca2+ and CO3(2-), with Ca2+ played a dominant role and CO3(2-) played a minor role. To find out which pathway was responsible for the accumulation of alpha-KG, the effects of biotin and thiamine on alpha-KG accumulation was investigated. The increase in biotin concentration led to an increase in alpha-KG accumulation and a decrease in C(PYR)/ C(alpha-KG), while the levels of alpha-KG and C(PYR)/C(alphaKG) were not affected by thiamine concentration. The activity of pyruvate carboxylase was increased as much as 40% when the medium was supplemented with Ca2+ . On the other hand, the activity of the pyruvate dehydrogenase complex was unaffected by the presence of Ca2+. To conclude, the higher level of a-KG was caused by higher activity of pyruvate carboxylase stimulated by Ca2+, with CO3(2-) served as the substrate of the reaction.

  12. Interaction and accumulation of manganese and cadmium in the manganese accumulator Lupinus albus.

    PubMed

    Zornoza, Pilar; Sánchez-Pardo, Beatriz; Carpena, Ramón O

    2010-09-01

    The effects of the interaction between Mn and Cd on the growth of the white lupin (Lupinus albus), uptake of these metals, their accumulation, and effects on heavy metal stress indicators were studied under glasshouse conditions. Plants were grown with and without Mn and/or Cd for 4 weeks. The absence of Mn and Cd led to lipid peroxidation-induced loss of flavonoids and anthocyanins in the roots, reduced the size of the plant canopy, and led to the appearance of proteoid roots. Sensitivity to Cd in white lupin was enhanced by a low Mn supply, despite lower Cd uptake and accumulation (leaf Mn:Cd concentration ratio <3), as evidenced by increased lipid peroxidation in the leaves and strong inhibition of growth. However, when the Mn supply was adequate, the plants showed few symptoms of Cd toxicity, even though Cd uptake and accumulation increased. A Mn:Cd ratio of up to 20 was enough to minimize Cd stress in the leaf, reflecting the plants' relative tolerance to Cd under such conditions. Irrespective of the Mn supply, the increase in antioxidant compounds observed in the roots of Cd-treated plants might act as a protective mechanism by minimizing the oxidative stress caused by Cd exposure. In summary, high leaf Mn concentrations seem to render white lupins more tolerant to Cd stress. Copyright 2010 Elsevier GmbH. All rights reserved.

  13. Surface-atmosphere decoupling limits accumulation at Summit, Greenland

    PubMed Central

    Berkelhammer, Max; Noone, David C.; Steen-Larsen, Hans Christian; Bailey, Adriana; Cox, Christopher J.; O’Neill, Michael S.; Schneider, David; Steffen, Konrad; White, James W. C.

    2016-01-01

    Despite rapid melting in the coastal regions of the Greenland Ice Sheet, a significant area (~40%) of the ice sheet rarely experiences surface melting. In these regions, the controls on annual accumulation are poorly constrained owing to surface conditions (for example, surface clouds, blowing snow, and surface inversions), which render moisture flux estimates from myriad approaches (that is, eddy covariance, remote sensing, and direct observations) highly uncertain. Accumulation is partially determined by the temperature dependence of saturation vapor pressure, which influences the maximum humidity of air parcels reaching the ice sheet interior. However, independent proxies for surface temperature and accumulation from ice cores show that the response of accumulation to temperature is variable and not generally consistent with a purely thermodynamic control. Using three years of stable water vapor isotope profiles from a high altitude site on the Greenland Ice Sheet, we show that as the boundary layer becomes increasingly stable, a decoupling between the ice sheet and atmosphere occurs. The limited interaction between the ice sheet surface and free tropospheric air reduces the capacity for surface condensation to achieve the rate set by the humidity of the air parcels reaching interior Greenland. The isolation of the surface also acts to recycle sublimated moisture by recondensing it onto fog particles, which returns the moisture back to the surface through gravitational settling. The observations highlight a unique mechanism by which ice sheet mass is conserved, which has implications for understanding both past and future changes in accumulation rate and the isotopic signal in ice cores from Greenland. PMID:27386509

  14. Surface-atmosphere decoupling limits accumulation at Summit, Greenland.

    PubMed

    Berkelhammer, Max; Noone, David C; Steen-Larsen, Hans Christian; Bailey, Adriana; Cox, Christopher J; O'Neill, Michael S; Schneider, David; Steffen, Konrad; White, James W C

    2016-04-01

    Despite rapid melting in the coastal regions of the Greenland Ice Sheet, a significant area (~40%) of the ice sheet rarely experiences surface melting. In these regions, the controls on annual accumulation are poorly constrained owing to surface conditions (for example, surface clouds, blowing snow, and surface inversions), which render moisture flux estimates from myriad approaches (that is, eddy covariance, remote sensing, and direct observations) highly uncertain. Accumulation is partially determined by the temperature dependence of saturation vapor pressure, which influences the maximum humidity of air parcels reaching the ice sheet interior. However, independent proxies for surface temperature and accumulation from ice cores show that the response of accumulation to temperature is variable and not generally consistent with a purely thermodynamic control. Using three years of stable water vapor isotope profiles from a high altitude site on the Greenland Ice Sheet, we show that as the boundary layer becomes increasingly stable, a decoupling between the ice sheet and atmosphere occurs. The limited interaction between the ice sheet surface and free tropospheric air reduces the capacity for surface condensation to achieve the rate set by the humidity of the air parcels reaching interior Greenland. The isolation of the surface also acts to recycle sublimated moisture by recondensing it onto fog particles, which returns the moisture back to the surface through gravitational settling. The observations highlight a unique mechanism by which ice sheet mass is conserved, which has implications for understanding both past and future changes in accumulation rate and the isotopic signal in ice cores from Greenland.

  15. Differential accumulation and pigmenting ability of dietary carotenoids in colorful finches.

    PubMed

    McGraw, Kevin J; Hill, Geoffrey E; Navara, Kristen J; Parker, Robert S

    2004-01-01

    Many animals develop bright red, orange, or yellow carotenoid pigmentation that they use to attract mates. Colorful carotenoid pigments are acquired from the diet and are either directly incorporated as integumentary colorants or metabolized into other forms before deposition. Because animals often obtain several different carotenoids from plant and animal food sources, it is possible that these pigments are accumulated at different levels in the body and may play unique roles in shaping the ultimate color expression of individuals. We studied patterns of carotenoid accumulation and integumentary pigmentation in two colorful finch species--the American goldfinch (Carduelis tristis) and the zebra finch (Taeniopygia guttata). Both species acquire two main hydroxycarotenoids, lutein and zeaxanthin, from their seed diet but transform these into a series of metabolites that are used as colorful pigments in the plumage (goldfinches only) and beak (both species). We conducted a series of carotenoid-supplementation experiments to investigate the relative extent to which lutein and zeaxanthin are accumulated in blood and increase carotenoid coloration in feathers and bare parts. First, we supplemented the diets of both species with either lutein or zeaxanthin and measured plasma pigment status, feather carotenoid concentration (goldfinches only), and integumentary color. Zeaxanthin-supplemented males grew more colorful feathers and beaks than lutein-supplemented males, and in goldfinches incorporated a different ratio of carotenoids in feathers (favoring the accumulation of canary xanthophyll B). We also fed goldfinches different concentrations of a standard lutein-zeaxanthin mix and found that at physiologically normal and high concentrations, birds circulated proportionally more zeaxanthin over lutein than occurred in the diet. Collectively, these results demonstrate that zeaxanthin is preferentially accumulated in the body and serves as a more potent substrate for

  16. The effect of solvent polarity on the accumulation of leachables from pharmaceutical product containers.

    PubMed

    Jenke, Dennis; Odufu, Alex; Poss, Mitchell

    2006-02-01

    Material/water equilibrium interaction constants (E(b)) were determined for 12 organic model solutes and a plastic material used in pharmaceutical product containers (non-PVC polyolefin). An excellent correlation was obtained between the measured interaction constants and the organic solute's octanol/water partition coefficient. The effect of solvent polarity on E(b) was assessed by examining the interaction between the plastic and selected model solutes in binary ethanol/water mixtures. In general, logE(b) could be linearily related to the polarity of the ethanol/water mixture. This information, coupled with the interaction model, was used to estimate the levels to which container leachables could accumulate in contacted solutions. Such estimates were made for six known leachables of the polyolefin material and compared to the leachable's measured accumulation levels in binary ethanol/water systems. In general, the accumulation level of the leachables increased with increasing solution polarity. For most of the leachables, the measured accumulation level was less than the calculated levels, suggesting that equilibrium was not achieved in the leaching portion of this study. This lack of equilibrium is attributable to the layered structure of the material studied, as such layering retards the migration of the leachables that are derived from the material's non-solution contact layers.

  17. A survey of mangiferin and hydroxycinnamic acid ester accumulation in coffee (Coffea) leaves: biological implications and uses

    PubMed Central

    Campa, Claudine; Mondolot, Laurence; Rakotondravao, Arsene; Bidel, Luc P. R.; Gargadennec, Annick; Couturon, Emmanuel; La Fisca, Philippe; Rakotomalala, Jean-Jacques; Jay-Allemand, Christian; Davis, Aaron P.

    2012-01-01

    Background and Aims The phenolic composition of Coffea leaves has barely been studied, and therefore this study conducts the first detailed survey, focusing on mangiferin and hydroxycinnamic acid esters (HCEs). Methods Using HPLC, including a new technique allowing quantification of feruloylquinic acid together with mangiferin, and histochemical methods, mangiferin content and tissue localization were compared in leaves and fruits of C. pseudozanguebariae, C. arabica and C. canephora. The HCE and mangiferin content of leaves was evaluated for 23 species native to Africa or Madagascar. Using various statistical methods, data were assessed in relation to distribution, ecology, phylogeny and use. Key Results Seven of the 23 species accumulated mangiferin in their leaves. Mangiferin leaf-accumulating species also contain mangiferin in the fruits, but only in the outer (sporophytic) parts. In both leaves and fruit, mangiferin accumulation decreases with ageing. A relationship between mangiferin accumulation and UV levels is posited, owing to localization with photosynthetic tissues, and systematic distribution in high altitude clades and species with high altitude representatives. Analyses of mangiferin and HCE content showed that there are significant differences between species, and that samples can be grouped into species, with few exceptions. These data also provide independent support for various Coffea lineages, as proposed by molecular phylogenetic analyses. Sampling of the hybrids C. arabica and C. heterocalyx cf. indicates that mangiferin and HCE accumulation may be under independent parental influence. Conclusions This survey of the phenolic composition in Coffea leaves shows that mangiferin and HCE accumulation corresponds to lineage recognition and species delimitation, respectively. Knowledge of the spectrum of phenolic accumulation within species and populations could be of considerable significance for adaptation to specific environments. The potential

  18. Toxic effects of two sources of dietborne cadmium on the juvenile cobia, Rachycentron canadum L. and tissue-specific accumulation of related minerals.

    PubMed

    Liu, Kang; Chi, Shuyan; Liu, Hongyu; Dong, Xiaohui; Yang, Qihui; Zhang, Shuang; Tan, Beiping

    2015-08-01

    In the present study, juvenile cobia, Rachycentron canadum L. were fed diets contaminated by two different sources of cadmium: squid viscera meal (SVM-Cd, organic form) and cadmium chloride (CdCl2-Cd, inorganic form). The Cd concentrations in fish diet were approximate 3.0, 5.0 and 10.0mg Cd kg(-1) for both inorganic and organic forms. In the control diet (0.312mg Cd kg(-1) diet, Cd mainly come from fish meal), no cadmium was added. The experiment lasted for 16 weeks and a statistically significant inverse relationship was observed between specific growth rate (SGR) and the concentration of dietary Cd. The SGR of cobia fed a diet with SVM-Cd increased at the lowest doses and decreased with the increasing level of dietary SVM. Fish fed diet contaminated SVM-Cd had significantly higher SGR than those fed diets contaminated CdCl2-Cd among the high Cd level diets treatments. The dietary Cd levels also significantly affected the survival rate of the fish. Among the hematological characteristics and plasma constituents, glutamic-pyruvic transaminase activities and alkaline phosphatase activities in serum and liver increased and hepatic superoxide dismutase activity decreased with the increasing dietary Cd levels. The cobia fed diet contaminated by high level of CdCl2-Cd had significantly higher ALP activity than cobia fed diet contaminated by high level of SVM-Cd. The results from these studies indicate no differences in toxicity response to dietborne SVM-Cd and CdCl2-Cd at a low level of Cd. However, at a higher level, cobia was more sensitive to dietborne CdCl2-Cd than SVM-Cd. Based on quadratic regression of SGR, The Cd concentrations was 3.617mg kg(-1) in the optimal diet, Cd source was SVM (126mg Cd kg(-1) in SVM) which stimulate the growth of cobia and the added level was determined to be 26.7g kg(-1) diet in the present study. Cd accumulations in the kidney of cobia fed both types of Cd were higher than other tissues, and the order of Cd accumulation in tissues

  19. Varietal Dependence of GLVs Accumulation and LOX-HPL Pathway Gene Expression in Four Vitis vinifera Wine Grapes

    PubMed Central

    Qian, Xu; Xu, Xiao-Qing; Yu, Ke-Ji; Zhu, Bao-Qing; Lan, Yi-Bin; Duan, Chang-Qing; Pan, Qiu-Hong

    2016-01-01

    Variety is one of the major factors influencing grape and wine aromatic characteristics. Green leaf volatiles (GLVs), derived from lipoxygenase-hydroperoxides lyase (LOX-HPL) pathway, are important components for the aromatic quality of grapes and wines. However, the varietal difference regarding GLVs accumulation and related gene expression are poorly studied. This work exhibited that the accumulation of various GLVs and the expression of LOX-HPL pathway genes in four Vitis vinifera wine grape cultivars: Syrah, Muscat Tchervine, Gewürztraminer and Chardonnay. The results showed a variety dependence of GLVs profile. Muscat Tchervine harvested grapes contained less C6 aldehydes and the most abundant esters, which corresponded to very low VvLOXA and VvHPL1 expression abundance as well as high VvAAT transcript in this variety. High expression level of both VvLOXA and VvHPL1 paralleled with higher level of C6 aldehydes together with higher alcohols in Syrah grape. Gewürztraminer and Chardonnay grapes had high aldehydes and alcohols as well as low esters, which were resulted from their higher expression level of VvLOXA or VvHPL1 and lower VvAAT. From these above corresponding relations, it is concluded that VvLOXA, VvHPL1 and VvAAT in the LOX-HPL pathway are targets for altering GLVs composition in the grape varieties. PMID:27886056

  20. Enhanced land subsidence in Galveston Bay, Texas: Interaction between sediment accumulation rates and relative sea level rise

    NASA Astrophysics Data System (ADS)

    Al Mukaimi, Mohammad E.; Dellapenna, Timothy M.; Williams, Joshua R.

    2018-07-01

    Galveston Bay is the second largest estuary along the northern Gulf of Mexico coast, with a watershed containing one of largest concentrations of petroleum and chemical industries globally, as well as Houston, the fifth largest metropolitan area in the USA. Throughout the last century, extensive groundwater extraction to support these industries and an expanding population has resulted in significantly enhanced land subsidence (0.6-3.0 cm yr-1). The highest subsidence rates observed in the bay are within the lower 15 km of the San Jacinto River/Houston Ship Channel region (SJR/HSC), with distal areas in East and West Galveston Bays having subsidence rates on the order of 0.2 cm yr-1. In order to investigate the impacts of subsidence on sedimentation, a series of 22 vibracores were collected throughout the bay, and 210Pb and 137Cs radioisotope geochronologies and grain size distributions were determined. Sediment accumulation rates are highest (1.9 ± 0.5 cm yr-1) in the SJR/HSC, and decrease (<0.6 cm yr-1) both seaward and towards low subsidence regions. These results indicate sedimentation rates are significantly (p < 0.01) higher in areas with elevated Relative Sea Level Rise (RSLR). However, throughout most of Galveston Bay sedimentation rates are lower (as much as 50%) than estimated RSLR, indicating a sediment accretionary deficit. In areas (e.g., Scott Bay) within the SJR/HSC, the bay has deepened by more than 1.5 m, suggesting that sediment accumulation cannot keep pace with RSLR. Ultimately, this has resulted in a loss of coastal wetlands and a conversion of marine habitats from relatively shallow to deeper water settings.

  1. Abscisic Acid Accumulates at Positive Turgor Potential in Excised Soybean Seedling Growing Zones 1

    PubMed Central

    Creelman, Robert A.; Mullet, John E.

    1991-01-01

    Abscisic acid (ABA) accumulated in soybean (Glycine max [L.] Merr. cv Williams) hypocotyl elongating regions when seedlings were transferred to low water potential vermiculite (Ψ = −0.3 megapascals) even though positive turgor is retained in this tissue. Accumulation of ABA in growing zones could occur from de novo biosynthesis within this tissue or transport from adjacent nongrowing zones. Both growing and nongrowing hypocotyl and root tissues accumulated significant levels of ABA when excised and dehydrated to reduce turgor. Surprisingly, excised growing zones (which experienced no water loss) also accumulated ABA when incubated in darkness for 4 hours at 100% relative humidity and 29°C. Induction of ABA accumulation in the excised elongating region of the hypocotyl was not caused by disruption of root pressure or wounding. While excision of hypocotyl elongating regions induced ABA accumulation, no change in either extensin or p33 mRNA levels was observed. Accumulation of extensin or p33 mRNA required more severe wounding. This suggests that ABA is not involved in the response of these genes in wounded tissue and that wound signals are not causing ABA accumulation in excised tissue. Accumulation of ABA in excised elongating regions was correlated with growth inhibition and a decline in turgor to the yield threshold (Ψ;p = 0.37 megapascals; R Matyssek, S Maruyama, JS Boyer [1988] Plant Physiol 86: 1163-1167). Inhibiting hypocotyl growth by transferring seedlings to lower temperatures or light did not cause ABA accumulation. We conclude that induction of ABA accumulation in growing zones is more sensitive to changes in turgor than the induction which occurs in mature tissues. Images Figure 2 PMID:16668113

  2. Effect of Salt Stress on Growth, Na+ Accumulation and Proline Metabolism in Potato (Solanum tuberosum) Cultivars

    PubMed Central

    Jaarsma, Rinse; de Vries, Rozemarijn S. M.; de Boer, Albertus H.

    2013-01-01

    Potato (Solanum tuberosum) is a major crop world-wide and the productivity of currently used cultivars is strongly reduced at high soil salt levels. We compared the response of six potato cultivars to increased root NaCl concentrations. Cuttings were grown hydroponically and treated with 0 mM, 60 mM and 180 mM NaCl for one week. Growth reduction on salt was strongest for the cultivars Mozart and Mona Lisa with a severe senescence response at 180 mM NaCl and Mozart barely survived the treatment. The cultivars Desiree and Russett Burbank were more tolerant showing no senescence after salt treatment. A clear difference in Na+ homeostasis was observed between sensitive and tolerant cultivars. The salt sensitive cultivar Mozart combined low Na+ levels in root and stem with the highest leaf Na+ concentration of all cultivars, resulting in a high Na+ shoot distribution index (SDI) for Mozart as compared to Desiree. Overall, a positive correlation between salt tolerance and stem Na+ accumulation was found and the SDI for Na+ points to a role of stem Na+ accumulation in tolerance. In stem tissue, Mozart accumulated more H2O2 and less proline compared to the tolerant cultivars. Analysis of the expression of proline biosynthesis genes in Mozart and Desiree showed a clear reduction in proline dehydrogenase (PDH) expression in both cultivars and an increase in pyrroline-5-carboxylate synthetase 1 (P5CS1) gene expression in Desiree, but not in Mozart. Taken together, current day commercial cultivars show promising differences in salt tolerance and the results suggest that mechanisms of tolerance reside in the capacity of Na+ accumulation in stem tissue, resulting in reduced Na+ transport to the leaves. PMID:23533673

  3. Effect of Various Conditions on Accumulation of Oxytetracycline in Escherichia coli

    PubMed Central

    Izaki, Kazuo; Arima, Kei

    1965-01-01

    Izaki, Kazuo (University of Tokyo, Tokyo, Japan), and Kei Arima. Effect of various conditions on accumulation of oxytetracycline in Escherichia coli. J. Bacteriol. 89:1335–1339. 1965.—Accumulation of large amounts of oxytetracycline occurred in Escherichia coli when the cells were incubated with high concentrations of oxytetracycline (100 to 400 μg/ml) in nutrient broth or in a medium containing glucose, K2HPO4, and MgSO4. In the absence of glucose or MgSO4, the accumulation was very small. The optimal pH for accumulation was about 6.5. Manganous ion could replace Mg++ in promoting the accumulation, though with decreased effectiveness. Malate and succinate were effective promoters of accumulation as well as glucose. Accumulation was inhibited at low temperatures or in the presence of metabolic inhibitors such as 2,4-dinitrophenol or sodium azide. Images PMID:14293007

  4. Copper accumulation in senescent cells: Interplay between copper transporters and impaired autophagy.

    PubMed

    Masaldan, Shashank; Clatworthy, Sharnel A S; Gamell, Cristina; Smith, Zoe M; Francis, Paul S; Denoyer, Delphine; Meggyesy, Peter M; Fontaine, Sharon La; Cater, Michael A

    2018-06-01

    Cellular senescence is characterized by irreversible growth arrest incurred through either replicative exhaustion or by pro-oncogenic cellular stressors (radioactivity, oxidative stress, oncogenic activation). The enrichment of senescent cells in tissues with age has been associated with tissue dyshomeostasis and age-related pathologies including cancers, neurodegenerative disorders (e.g. Alzheimer's, Parkinson's, etc.) and metabolic disorders (e.g. diabetes). We identified copper accumulation as being a universal feature of senescent cells [mouse embryonic fibroblasts (MEF), human prostate epithelial cells and human diploid fibroblasts] in vitro. Elevated copper in senescent MEFs was accompanied by elevated levels of high-affinity copper uptake protein 1 (Ctr1), diminished levels of copper-transporting ATPase 1 (Atp7a) (copper export) and enhanced antioxidant defence reflected by elevated levels of glutathione (GSH), superoxide dismutase 1 (SOD1) and glutaredoxin 1 (Grx1). The levels of intracellular copper were further increased in senescent MEFs cultured in copper supplemented medium and in senescent Mottled Brindled (Mo br ) MEFs lacking functional Atp7a. Finally, we demonstrated that the restoration/preservation of autophagic-lysosomal degradation in senescent MEFs following rapamycin treatment correlated with attenuation of copper accumulation in these cells despite a further decrease in Atp7a levels. This study for the first time establishes a link between Atp7a and the autophagic-lysosomal pathway, and a requirement for both to effect efficient copper export. Such a connection between cellular autophagy and copper homeostasis is significant, as both have emerged as important facets of age-associated degenerative disease. Copyright © 2018. Published by Elsevier B.V.

  5. Do we understand high-level vision?

    PubMed

    Cox, David Daniel

    2014-04-01

    'High-level' vision lacks a single, agreed upon definition, but it might usefully be defined as those stages of visual processing that transition from analyzing local image structure to analyzing structure of the external world that produced those images. Much work in the last several decades has focused on object recognition as a framing problem for the study of high-level visual cortex, and much progress has been made in this direction. This approach presumes that the operational goal of the visual system is to read-out the identity of an object (or objects) in a scene, in spite of variation in the position, size, lighting and the presence of other nearby objects. However, while object recognition as a operational framing of high-level is intuitive appealing, it is by no means the only task that visual cortex might do, and the study of object recognition is beset by challenges in building stimulus sets that adequately sample the infinite space of possible stimuli. Here I review the successes and limitations of this work, and ask whether we should reframe our approaches to understanding high-level vision. Copyright © 2014. Published by Elsevier Ltd.

  6. Caesium and strontium accumulation in shoots of Arabidopsis thaliana: genetic and physiological aspects

    PubMed Central

    Kanter, Ulrike; Hauser, Andreas; Michalke, Bernhard; Dräxl, Stephan; Schäffner, Anton R.

    2010-01-01

    Due to the physico-chemical similarities of caesium (Cs+) to potassium (K+) on the one hand and strontium (Sr2+) to calcium (Ca2+) on the other hand, both elements can easily be taken up by plants and thus enter the food chain. This could be detrimental when radionuclides such as 137Cs and 90Sr are involved. In this study, both genetic and physiological aspects of Cs+ and Sr2+ accumulation in Arabidopsis thaliana were investigated using 86 Arabidopsis accessions and a segregating F2 population of the low Cs+ accumulating Sq-1 (Ascot, UK) crossed with the high uptaking Sorbo (Khurmatov, Tajikistan). Hydroponically grown plants were exposed to subtoxic levels of Cs+ and Sr2+ using radioactive isotopes as tracers. In the natural accessions shoot concentration of Cs+ as well as Sr2+ varied about 2-fold, whereas its heritability ranged for both ions between 0.60 and 0.73. Shoot accumulation of Cs+ and Sr2+ could be compromised by increasing concentrations of their essential analogues K+ and Ca2+, respectively, causing a reduction of up to 80%. In the case of the segregating F2/F3 population Sq-1×Sorbo, this study identified several QTL for the trait Cs+ and Sr2+ accumulation, with main QTL on chromosomes 1 and 5. According to the correlation and discrimination surveys combined with QTL-analysis Cs+ and Sr2+ uptake seemed to be mediated mostly via non-selective cation channels. A polymorphism, affecting amino acids close to the K+-pore of one candidate, CYCLIC-NUCLEOTIDE-GATED CHANNEL 1 (CNGC1), was identified in Sorbo and associated with high Cs+ concentrating accessions. PMID:20624763

  7. [Accumulative levels of organochlorine pesticides of HCHs, DDTs in breast milk and risk factors analysis in Shenzhen].

    PubMed

    Shi, Rongjie; Zhong, Yuetong; Lei, Yixiong; Zhang, Jianqing; Li, Shengnong; Jiang, Yousheng; Zhou, Jian; Lu, Shaoyou

    2013-03-01

    To first investigate the accumulative levels of DDTs and HCHs in human breast milk of primipara in Shenzhen area, analyze influencing factors and assess exposure risk of infant in Shenzhen. From April in 2011 to April in 2012, 85 primiparas who have lived in Shenzhen over 3 years after parturition 4 - 6 weeks were recruited, and their breast milk were collected and questionnaires were filled out simultaneously. The samples were extracted five times with hexane, cleaned up by gel permeation chromatograph (GPC) and SPE, and quantified by gas chromatography-election capture detection (GC-ECD). Correlations between DDTs, HCHs and maternal age, weight, dietary, living time as well as infant birth weight and length were also analyzed with the SPSS 13.0 statistical software respectively. Among the several groups of DDTs and HCHs metabolites, p,p'-DDE were detected in total 85 samples and beta-HCH were detected in 58 samples, which accounted for 68.2% of the breast milk. The median levels of sigmaHCHs and sigma DDTs were 2.980 ng/g whole weight (80.200 ng/g fat) and 9.610 ng/g whole weight (268.390 ng/g fat). Both levels of sigmaHCHs and sigmaDDTs in the human milk had a positive association with maternal age among the demographic characteristics of primiparas. Furthermore, levels of sigma HCHs were positively correlated with freshwater fish consumption. However, sigma DDTs levels which were calculated in fat had a positive association only with the amount of poultry meat intake. Beta-HCH and p,p'-DDE were detected in human breast milk, and correlated with age and dietary intake. The average estimated daily intakes of HCHs and DDTs by infants are 0.468, 1.842 microg/(kg x BW x d) respectively, lower than acceptable daily intakes (ADI) proposed by the Ministry of Health of China and (the WHO/FAO) Joint Meeting of Pesticide Residues (JMPR). The average levels of HCHs, DDTs in the breast milk in Shenzhen general population are lower than those of Chinese average level.

  8. Systems Level Regulation of Rhythmic Growth Rate and Biomass Accumulation in Grasses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kay, Steve A.

    Objectives: Several breakthroughs have been recently made in our understanding of plant growth and biomass accumulation. It was found that plant growth is rhythmically controlled throughout the day by the circadian clock through a complex interplay of light and phytohormone signaling pathways. While plants such as the C4 energy crop sorghum (Sorghum bicolor (L.) Moench) and possibly the C3 grass Brachypodium distachyon also exhibit daily rhythms in growth rate, the molecular details of its regulation remain to be explored. A better understanding of diurnally regulated growth behavior in grasses may lead to species-specific mechanisms highly relevant to future strategies tomore » optimize energy crop biomass yield. Here we propose to devise a systems approach to identify, in parallel, regulatory hubs associated with rhythmic growth in C3 and C4 plants. We propose to use rhythmicity in daily growth patterns to drive the discovery of regulatory network modules controlling biomass accumulation. Description: The project is divided in three main parts: 1) Performing time-lapse imaging and growth measurement in B. distachyon and S. bicolor to determine growth rate dynamic during the day/night cycle. Identifying growth-associated genes whose expression patterns follow the observed growth dynamics using deep sequencing technology, 2) identifying regulators of these genes by screening for DNA-binding proteins interacting with the growth-associated gene promoters identified in Aim 1. Screens will be performed using a validated yeast-one hybrid strategy paired with a specifically designed B. distachyon and S. bicolor transcription factor libraries (1000 clones each), and 3) Selecting 50 potential growth regulators from the screen for downstream characterization. The selection will be made by using a sytems biology approach by calculating the connectivity between growth rate, rhythmic gene expression profiles and TF expression profile and determine which TF is likely part of

  9. Microbial cells can cooperate to resist high-level chronic ionizing radiation

    PubMed Central

    Gaidamakova, Elena K.; Tkavc, Rok; Grichenko, Olga; Klimenkova, Polina; Volpe, Robert P.; Daly, Michael J.

    2017-01-01

    Understanding chronic ionizing radiation (CIR) effects is of utmost importance to protecting human health and the environment. Diverse bacteria and fungi inhabiting extremely radioactive waste and disaster sites (e.g. Hanford, Chernobyl, Fukushima) represent new targets of CIR research. We show that many microorganisms can grow under intense gamma-CIR dose rates of 13–126 Gy/h, with fungi identified as a particularly CIR-resistant group of eukaryotes: among 145 phylogenetically diverse strains tested, 78 grew under 36 Gy/h. Importantly, we demonstrate that CIR resistance can depend on cell concentration and that certain resistant microbial cells protect their neighbors (not only conspecifics, but even radiosensitive species from a different phylum), from high-level CIR. We apply a mechanistically-motivated mathematical model of CIR effects, based on accumulation/removal kinetics of reactive oxygen species (ROS) and antioxidants, in bacteria (3 Escherichia coli strains and Deinococcus radiodurans) and in fungi (Candida parapsilosis, Kazachstania exigua, Pichia kudriavzevii, Rhodotorula lysinophila, Saccharomyces cerevisiae, and Trichosporon mucoides). We also show that correlations between responses to CIR and acute ionizing radiation (AIR) among studied microorganisms are weak. For example, in D. radiodurans, the best molecular correlate for CIR resistance is the antioxidant enzyme catalase, which is dispensable for AIR resistance; and numerous CIR-resistant fungi are not AIR-resistant. Our experimental findings and quantitative modeling thus demonstrate the importance of investigating CIR responses directly, rather than extrapolating from AIR. Protection of radiosensitive cell-types by radioresistant ones under high-level CIR is a potentially important new tool for bioremediation of radioactive sites and development of CIR-resistant microbiota as radioprotectors. PMID:29261697

  10. Microbial cells can cooperate to resist high-level chronic ionizing radiation.

    PubMed

    Shuryak, Igor; Matrosova, Vera Y; Gaidamakova, Elena K; Tkavc, Rok; Grichenko, Olga; Klimenkova, Polina; Volpe, Robert P; Daly, Michael J

    2017-01-01

    Understanding chronic ionizing radiation (CIR) effects is of utmost importance to protecting human health and the environment. Diverse bacteria and fungi inhabiting extremely radioactive waste and disaster sites (e.g. Hanford, Chernobyl, Fukushima) represent new targets of CIR research. We show that many microorganisms can grow under intense gamma-CIR dose rates of 13-126 Gy/h, with fungi identified as a particularly CIR-resistant group of eukaryotes: among 145 phylogenetically diverse strains tested, 78 grew under 36 Gy/h. Importantly, we demonstrate that CIR resistance can depend on cell concentration and that certain resistant microbial cells protect their neighbors (not only conspecifics, but even radiosensitive species from a different phylum), from high-level CIR. We apply a mechanistically-motivated mathematical model of CIR effects, based on accumulation/removal kinetics of reactive oxygen species (ROS) and antioxidants, in bacteria (3 Escherichia coli strains and Deinococcus radiodurans) and in fungi (Candida parapsilosis, Kazachstania exigua, Pichia kudriavzevii, Rhodotorula lysinophila, Saccharomyces cerevisiae, and Trichosporon mucoides). We also show that correlations between responses to CIR and acute ionizing radiation (AIR) among studied microorganisms are weak. For example, in D. radiodurans, the best molecular correlate for CIR resistance is the antioxidant enzyme catalase, which is dispensable for AIR resistance; and numerous CIR-resistant fungi are not AIR-resistant. Our experimental findings and quantitative modeling thus demonstrate the importance of investigating CIR responses directly, rather than extrapolating from AIR. Protection of radiosensitive cell-types by radioresistant ones under high-level CIR is a potentially important new tool for bioremediation of radioactive sites and development of CIR-resistant microbiota as radioprotectors.

  11. Betaine is accumulated via transient choline dehydrogenase activation during mouse oocyte meiotic maturation.

    PubMed

    McClatchie, Taylor; Meredith, Megan; Ouédraogo, Mariame O; Slow, Sandy; Lever, Michael; Mann, Mellissa R W; Zeisel, Steven H; Trasler, Jacquetta M; Baltz, Jay M

    2017-08-18

    Betaine ( N,N,N -trimethylglycine) plays key roles in mouse eggs and preimplantation embryos first in a novel mechanism of cell volume regulation and second as a major methyl donor in blastocysts, but its origin is unknown. Here, we determined that endogenous betaine was present at low levels in germinal vesicle (GV) stage mouse oocytes before ovulation and reached high levels in the mature, ovulated egg. However, no betaine transport into oocytes was detected during meiotic maturation. Because betaine can be synthesized in mammalian cells via choline dehydrogenase (CHDH; EC 1.1.99.1), we assessed whether this enzyme was expressed and active. Chdh transcripts and CHDH protein were expressed in oocytes. No CHDH enzyme activity was detected in GV oocyte lysate, but CHDH became highly active during oocyte meiotic maturation. It was again inactive after fertilization. We then determined whether oocytes synthesized betaine and whether CHDH was required. Isolated maturing oocytes autonomously synthesized betaine in vitro in the presence of choline, whereas this failed to occur in Chdh -/- oocytes, directly demonstrating a requirement for CHDH for betaine accumulation in oocytes. Overall, betaine accumulation is a previously unsuspected physiological process during mouse oocyte meiotic maturation whose underlying mechanism is the transient activation of CHDH. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Characterization of 68Zn uptake, translocation, and accumulation into developing grains and young leaves of high Zn-density rice genotype*

    PubMed Central

    Wu, Chun-yong; Feng, Ying; Shohag, Md. Jahidul Islam; Lu, Ling-li; Wei, Yan-yan; Gao, Chong; Yang, Xiao-e

    2011-01-01

    Zinc (Zn) is an essential micronutrient for humans, but Zn deficiency has become serious as equally as iron (Fe) and vitamin A deficiencies nowadays. Selection and breeding of high Zn-density crops is a suitable, cost-effective, and sustainable way to improve human health. However, the mechanism of high Zn density in rice grain is not fully understood, especially how Zn transports from soil to grains. Hydroponics experiments were carried out to compare Zn uptake and distribution in two different Zn-density rice genotypes using stable isotope technique. At seedling stage, IR68144 showed higher 68Zn uptake and transport rate to the shoot for the short-term, but no significant difference was observed in both genotypes for the long-term. Zn in xylem sap of IR68144 was consistently higher, and IR68144 exhibited higher Zn absorption ratio than IR64 at sufficient (2.0 µmol/L) or surplus (8.0 µmol/L) Zn supply level. IR64 and IR68144 showed similar patterns of 68Zn accumulation in new leaves at seedling stage and in developing grains at ripening stage, whereas 68Zn in new leaves and grains of IR68144 was consistently higher. These results suggested that a rapid root-to-shoot translocation and enhanced xylem loading capacity may be the crucial processes for high Zn density in rice grains. PMID:21528496

  13. Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh

    PubMed Central

    Salman, Verena; Yang, Tingting; Berben, Tom; Klein, Frieder; Angert, Esther; Teske, Andreas

    2015-01-01

    Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium. PMID:25909974

  14. Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh.

    PubMed

    Salman, Verena; Yang, Tingting; Berben, Tom; Klein, Frieder; Angert, Esther; Teske, Andreas

    2015-11-01

    Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium.

  15. Chlorophyll, Carotenoid and Anthocyanin Accumulation in Mung Bean Seedling Under Clinorotation

    NASA Astrophysics Data System (ADS)

    Nakajima, Shusaku; Shiraga, Keiichiro; Suzuki, Tetsuhito; Kondo, Naoshi; Ogawa, Yuichi

    2017-12-01

    The accumulation of plant pigments in mung bean ( Vigna radiata L.) seedlings was measured after clinorotation (2 rpm for 2-4 days), and compared to a stationary control. The pigments measured included chlorophyll and carotenoid in primary leaves, and the anthocyanin in seedlings. While significant changes in chlorophyll and carotenoid accumulation were not observed during the initial 2 to 4 days of cultivation, by day 4 the seedlings grown on the clinostat had lower levels of anthocyanin, compared to those in the control seedlings. To further detail the cause for the observed reduction in anthocyanin accumulation under altered gravity conditions, seedlings were grown in the presence of silver nitrate, a known ethylene inhibitor, for 4 days, since it is known ethylene has a negative impact on anthocyanin accumulation. Silver nitrate promoted anthocyanin accumulation in the clinostat seedlings, and as a result there was no significant difference between the control and clinostat seedlings in anthocyanin accumulation. The results suggest that slow clinorotation negatively impacts anthocyanin pigmentation in mung bean seedlings, with endogenous ethylene suspected to be involved in this.

  16. Ascorbate biosynthesis during early fruit development is the main reason for its accumulation in kiwi.

    PubMed

    Li, Mingjun; Ma, Fengwang; Liang, Dong; Li, Juan; Wang, Yanlei

    2010-12-09

    Ascorbic acid (AsA) is a unique antioxidant as well as an enzyme cofactor. Although it has multiple roles in plants, it is unclear how its accumulation is controlled at the expression level, especially in sink tissues. Kiwifruit (Actinidia) is well-known for its high ascorbate content. Our objective was to determine whether AsA accumulates in the fruits primarily through biosynthesis or because it is imported from the foliage. We systematically investigated AsA levels, biosynthetic capacity, and mRNA expression of genes involved in AsA biosynthesis in kiwi (A. deliciosa cv. Qinmei). Recycling and AsA localization were also monitored during fruit development and among different tissue types. Over time, the amount of AsA, with its capacity for higher biosynthesis and lower recycling, peaked at 30 days after anthesis (DAA), and then decreased markedly up to 60 DAA before declining more slowly. Expression of key genes showed similar patterns of change, except for L-galactono-1,4-lactone dehydrogenase and L-galactose-1-phosphate phosphatase (GPP). However, GPP had good correlation with the rate of AsA accumulation. The expression of these genes could be detected in phloem of stem as well as petiole of leaf and fruit. Additionally, fruit petioles had greater ascorbate amounts, although that was the site of lowest expression by most genes. Fruit microtubule tissues also had higher AsA. However, exogenous applications of AsA to those petioles did not lead to its transport into fruits, and distribution of ascorbate was cell-specific in the fruits, with more accumulation occurring in larger cells. These results suggest that AsA biosynthesis in kiwi during early fruit development is the main reason for its accumulation in the fruits. We also postulate here that GPP is a good candidate for regulating AsA biosynthesis whereas GDP-L-galactose-1-phosphate phosphorylase is not.

  17. Uridine prevents tamoxifen-induced liver lipid droplet accumulation

    PubMed Central

    2014-01-01

    Background Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Methods Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1−/−and UPase1-TG. Results Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1−/−with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had

  18. Uridine prevents tamoxifen-induced liver lipid droplet accumulation.

    PubMed

    Le, Thuc T; Urasaki, Yasuyo; Pizzorno, Giuseppe

    2014-05-23

    Tamoxifen, an agonist of estrogen receptor, is widely prescribed for the prevention and long-term treatment of breast cancer. A side effect of tamoxifen is fatty liver, which increases the risk for non-alcoholic fatty liver disease. Prevention of tamoxifen-induced fatty liver has the potential to improve the safety of long-term tamoxifen usage. Uridine, a pyrimidine nucleoside with reported protective effects against drug-induced fatty liver, was co-administered with tamoxifen in C57BL/6J mice. Liver lipid levels were evaluated with lipid visualization using coherent anti-Stokes Raman scatting (CARS) microscopy, biochemical assay measurement of triacylglyceride (TAG), and liquid chromatography coupled with mass spectrometry (LC-MS) measurement of membrane phospholipid. Blood TAG and cholesterol levels were measured. Mitochondrial respiration of primary hepatocytes in the presence of tamoxifen and/or uridine was evaluated by measuring oxygen consumption rate with an extracellular flux analyzer. Liver protein lysine acetylation profiles were evaluated with 1D and 2D Western blots. In addition, the relationship between endogenous uridine levels, fatty liver, and tamoxifen administration was evaluated in transgenic mice UPase1-/-and UPase1-TG. Uridine co-administration prevented tamoxifen-induced liver lipid droplet accumulation in mice. The most prominent effect of uridine co-administration with tamoxifen was the stimulation of liver membrane phospholipid biosynthesis. Uridine had no protective effect against tamoxifen-induced impairment to mitochondrial respiration of primary hepatocytes or liver TAG and cholesterol export. Uridine had no effect on tamoxifen-induced changes to liver protein acetylation profile. Transgenic mice UPase1-/-with increased pyrimidine salvage activity were protected against tamoxifen-induced liver lipid droplet accumulation. In contrast, UPase1-TG mice with increased pyrimidine catabolism activity had intrinsic liver lipid droplet

  19. Evaluation of heavy metal and polycyclic aromatic hydrocarbons accumulation in plants from typical industrial sites: potential candidate in phytoremediation for co-contamination.

    PubMed

    Sun, Lu; Liao, Xiaoyong; Yan, Xiulan; Zhu, Ganghui; Ma, Dong

    2014-11-01

    The heavy metal and polycyclic aromatic hydrocarbons (PAHs) contents were evaluated in surface soil and plant samples of 18 wild species collected from 3 typical industrial sites in South Central China. The accumulative characteristics of the plant species for both heavy metal and PAHs were discussed. The simultaneous accumulation of heavy metal and PAHs in plant and soil was observed at all the investigated sites, although disparities in spatial distributions among sites occurred. Both plant and soil samples were characterized by high accumulation for heavy metal at smelting site, moderate enrichment at coke power and coal mining sites, whereas high level of PAHs (16 priority pollutants according to US Environmental Protection Agency) at coke power site, followed sequentially by coal mining and smelting sites. Based on the differences of heavy metal and PAH accumulation behaviors of the studied plant species, heavy metal and PAH accumulation strategies were suggested: Pteris vittata L. and Pteris cretica L. for As and PAHs, Boehmeria nivea (L.) Gaud for Pb, As, and PAHs, and Miscanthus floridulu (Labnll.) Warb for Cu and PAHs. These native plant species could be proposed as promising materials for heavy metal and PAHs combined pollution remediation.

  20. Accumulation of uranium by immobilized persimmon tannin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakaguchi, Takashi; Nakajima, Akira

    1994-01-01

    We have discovered that the extracted juice of unripe astringent persimmon fruit, designated as kakishibu or shibuol, has an extremely high affinity for uranium. To develop efficient adsorbents for uranium, we tried to immobilize kakishibu (persimmon tannin) with various aldehydes and mineral acids. Persimmon tannin immobilized with glutaraldehyde can accumulate 1.71 g (14 mEq U) of uranium per gram of the adsorbent. The uranium accumulating capacity of this adsorbent is several times greater than that of commercially available chelating resins (2-3 mEq/g). Immobilized persimmon tannin has the most favorable features for uranium recovery; high selective adsorption ability, rapid adsorption rate,more » and applicability in both column and batch systems. The uranium retained on immobilized persimmon tannin can be quantitatively and easily eluted with a very dilute acid, and the adsorbent can thus be easily recycled in the adsorption-desorption process. Immobilized persimmon tannin also has a high affinity for thorium. 23 refs., 13 figs., 7 tabs.« less

  1. Transcript level coordination of carbon pathways during silicon starvation-induced lipid accumulation in the diatom Thalassiosira pseudonana

    DOE PAGES

    Smith, Sarah R.; Gle, Corine; Abbriano, Raffaela M.; ...

    2016-02-04

    Diatoms are one of the most productive and successful photosynthetic taxa on Earth and possess attributes such as rapid growth rates and production of lipids, making them candidate sources of renewable fuels. Despite their significance, few details of the mechanisms used to regulate growth and carbon metabolism are currently known, hindering metabolic engineering approaches to enhance productivity. To characterize the transcript level component of metabolic regulation, genome-wide changes in transcript abundance were documented in the model diatom Thalassiosira pseudonana on a time-course of silicon starvation. Growth, cell cycle progression, chloroplast replication, fatty acid composition, pigmentation, and photosynthetic parameters were characterizedmore » alongside lipid accumulation. Extensive coordination of large suites of genes was observed, highlighting the existence of clusters of coregulated genes as a key feature of global gene regulation in T. pseudonana. The identity of key enzymes for carbon metabolic pathway inputs (photosynthesis) and outputs (growth and storage) reveals these clusters are organized to synchronize these processes. Coordinated transcript level responses to silicon starvation are probably driven by signals linked to cell cycle progression and shifts in photophysiology. A mechanistic understanding of how this is accomplished will aid efforts to engineer metabolism for development of algal-derived biofuels.« less

  2. Effect of spaceflight on isoflavonoid accumulation in etiolated soybean seedlings

    NASA Technical Reports Server (NTRS)

    Levine, L. H.; Levine, H. G.; Stryjewski, E. C.; Prima, V.; Piastuch, W. C.; Sager, J. S. (Principal Investigator)

    2001-01-01

    In order to explore the potential impact of microgravity on flavonoid biosynthesis, we examined isoflavonoid levels in soybean (Glycine max) tissues generated under both spaceflight and clinorotation conditions. A 6-day Space Shuttle-based microgravity exposure resulted in enhanced accumulation of isoflavone glycosides (daidzin, 6"-O-malonyl-7-O-glucosyl daidzein, genistin, 6"-O-malonyl-7-O-glucosyl genistein) in hypocotyl and root tissues, but reduced levels in cotyledons (relative to 1g controls on Earth). Soybean seedlings grown on a horizontally rotating clinostat for 3, 4 and 5 days exhibited (relative to a vertical clinorotation control) an isoflavonoid accumulation pattern similar to the space-grown tissues. Elevated isoflavonoid levels attributable to the clinorotation treatment were transient, with the greatest increase observed in the three-day-treated tissues and smaller increases in the four- and five-day-treated tissues. Differences between stresses presented by spaceflight and clinorotation and the resulting biochemical adaptations are discussed, as is whether the increase in isoflavonoid concentrations were due to differential rates of development under the "gravity" treatments employed. Results suggest that spaceflight exposure does not impair isoflavonoid accumulation in developing soybean tissues and that isoflavonoids respond positively to microgravity as a biochemical strategy of adaptation.

  3. High hydrostatic pressure extract of garlic increases the HDL cholesterol level via up-regulation of apolipoprotein A-I gene expression in rats fed a high-fat diet

    PubMed Central

    2012-01-01

    Background Cardiovascular disease (CVD) is the number one cause of mortality worldwide and a low high-density lipoprotein cholesterol (HDL-C) level is an important marker of CVD risk. Garlic (Allium sativum) has been widely used in the clinic for treatment of CVD and regulation of lipid metabolism. This study investigated the effects of a high hydrostatic pressure extract of garlic (HEG) on HDL-C level and regulation of hepatic apolipoprotein A-I (apoA-I) gene expression. Methods Male Sprague–Dawley rats were divided into two groups and maintained on a high-fat control diet (CON) or high-fat control diet supplemented with high hydrostatic pressure extract of garlic (HEG) for 5 weeks. Changes in the expression of genes related to HDL-C metabolism were analyzed in liver, together with biometric and blood parameters. Results In the HEG group, the plasma triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased in comparison with the CON group (P < 0.05). Dietary HEG also lowered the hepatic TG and total cholesterol (TC) levels compared to the CON group. While the plasma HDL-C level and mRNA level of hepatic apoA-I, which is one of primarily proteins of HDL-C particle, were significantly increased in the HEG group compared to the CON group (P < 0.05). The gene expression of ATP-binding cassette transporter A1 (ABCA1) and lecithin:cholesterol acyltransferase (LCAT), importantly involved in the biogenesis in HDL, were also up-regulated by dietary HEG. Conclusions These results suggest that HEG ameliorates plasma lipid profiles and attenuates hepatic lipid accumulation in the high-fat fed rats. Our findings provides that the effects of HEG on the increase of the plasma HDL-C level was at least partially mediated by up-regulation of hepatic genes expression such as apoA-I, ABCA1, and LCAT in rats fed a high-fat diet. PMID:22713542

  4. High hydrostatic pressure extract of garlic increases the HDL cholesterol level via up-regulation of apolipoprotein A-I gene expression in rats fed a high-fat diet.

    PubMed

    Lee, Seohyun; Joo, Hyunjin; Kim, Chong-Tai; Kim, In-Hwan; Kim, Yangha

    2012-06-19

    Cardiovascular disease (CVD) is the number one cause of mortality worldwide and a low high-density lipoprotein cholesterol (HDL-C) level is an important marker of CVD risk. Garlic (Allium sativum) has been widely used in the clinic for treatment of CVD and regulation of lipid metabolism. This study investigated the effects of a high hydrostatic pressure extract of garlic (HEG) on HDL-C level and regulation of hepatic apolipoprotein A-I (apoA-I) gene expression. Male Sprague-Dawley rats were divided into two groups and maintained on a high-fat control diet (CON) or high-fat control diet supplemented with high hydrostatic pressure extract of garlic (HEG) for 5 weeks. Changes in the expression of genes related to HDL-C metabolism were analyzed in liver, together with biometric and blood parameters. In the HEG group, the plasma triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased in comparison with the CON group (P < 0.05). Dietary HEG also lowered the hepatic TG and total cholesterol (TC) levels compared to the CON group. While the plasma HDL-C level and mRNA level of hepatic apoA-I, which is one of primarily proteins of HDL-C particle, were significantly increased in the HEG group compared to the CON group (P < 0.05). The gene expression of ATP-binding cassette transporter A1 (ABCA1) and lecithin:cholesterol acyltransferase (LCAT), importantly involved in the biogenesis in HDL, were also up-regulated by dietary HEG. These results suggest that HEG ameliorates plasma lipid profiles and attenuates hepatic lipid accumulation in the high-fat fed rats. Our findings provides that the effects of HEG on the increase of the plasma HDL-C level was at least partially mediated by up-regulation of hepatic genes expression such as apoA-I, ABCA1, and LCAT in rats fed a high-fat diet.

  5. Melanin-independent accumulation of turgor pressure in appressoria of Phakopsora pachyrhizi

    USDA-ARS?s Scientific Manuscript database

    In some plant pathogenic fungi, turgor pressure accumulation in appressoria produces a mechanical force enabling the direct penetration of hyphae through the plant cell epidermis. Melanin has been reported to function as an impermeable barrier to osmolytes, which allow appressoria to accumulate high...

  6. Effects of specific organs on seed oil accumulation in Brassica napus L.

    PubMed

    Liu, Jing; Hua, Wei; Yang, Hongli; Guo, Tingting; Sun, Xingchao; Wang, Xinfa; Liu, Guihua; Wang, Hanzhong

    2014-10-01

    Seed oil content is an important agricultural characteristic in rapeseed breeding. Genetic analysis shows that the mother plant and the embryo play critical roles in regulating seed oil accumulation. However, the overwhelming majority of previous studies have focused on oil synthesis in the developing seed of rapeseed. In this study, to elucidate the roles of reproductive organs on oil accumulation, silique, ovule, and embryo from three rapeseed lines with high oil content (zy036, 6F313, and 61616) were cultured in vitro. The results suggest that zy036 silique wall, 6F313 seed coat, and 61616 embryo have positive impacts on the seed oil accumulation. In zy036, our previous studies show that high photosynthetic activity of the silique wall contributes to seed oil accumulation (Hua et al., 2012). Herein, by transcriptome sequencing and sucrose detection, we found that sugar transport in 6F313 seed coat might regulate the efficiency of oil synthesis by controlling sugar concentration in ovules. In 61616 embryos, high oil accumulation efficiency was partly induced by the elevated expression of fatty-acid biosynthesis-related genes. Our investigations show three organ-specific mechanisms regulating oil synthesis in rapeseed. This study provides new insights into the factors affecting seed oil accumulation in rapeseed and other oil crops. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice

    PubMed Central

    Uraguchi, Shimpei; Mori, Shinsuke; Kuramata, Masato; Kawasaki, Akira; Arao, Tomohito; Ishikawa, Satoru

    2009-01-01

    Physiological properties involved in divergent cadmium (Cd) accumulation among rice genotypes were characterized using the indica cultivar ‘Habataki’ (high Cd in grains) and the japonica cultivar ‘Sasanishiki’ (low Cd in grains). Time-dependence and concentration-dependence of symplastic Cd absorption in roots were revealed not to be responsible for the different Cd accumulation between the two cultivars because root Cd uptake was not greater in the Cd-accumulating cultivar ‘Habataki’ compared with ‘Sasanishiki’. On the other hand, rapid and greater root-to-shoot Cd translocation was observed in ‘Habataki’, which could be mediated by higher abilities in xylem loading of Cd and transpiration rate as a driving force. To verify whether different abilities in xylem-mediated shoot-to-root translocation generally account for the genotypic variation in shoot Cd accumulation in rice, the world rice core collection, consisting of 69 accessions which covers the genetic diversity of almost 32 000 accessions of cultivated rice, was used. The results showed strong correlation between Cd levels in xylem sap and shoots and grains among the 69 rice accessions. Overall, the results presented in this study revealed that the root-to-shoot Cd translocation via the xylem is the major and common physiological process determining the Cd accumulation level in shoots and grains of rice plants. PMID:19401409

  8. Cold-Induced Accumulation of hsp90 Transcripts in Brassica napus.

    PubMed Central

    Krishna, P.; Sacco, M.; Cherutti, J. F.; Hill, S.

    1995-01-01

    Characterization of the expression of hsp90 genes of Brassica napus by northern blot analysis and immunoblotting showed that the hsp90 mRNA and protein are present in all B. napus tissues examined, albeit at different levels. High levels of hsp90 mRNA and protein were found in young and rapidly dividing tissues such as shoot apices and flower buds, suggesting that hsp90 may have an important role in plant growth and development. A significant increase in hsp90 mRNA levels was detected in seedlings exposed to 5[deg]C. The transcript levels reached a maximum within 1 d of cold treatment and remained elevated for the entire duration of cold treatment. The levels of hsp90 mRNA rapidly decreased to the level found in control plants upon return to 20[deg]C. The cold-induced accumulation of hsp90 mRNA closely resembles the expression of two previously identified cold-regulated genes of B. napus. We have also confirmed cold regulation of hsp90 mRNA in spinach (Spinacea oleracea). Our results suggest a role for hsp90 in adaptation to cold temperature stress. PMID:12228411

  9. The accumulation and localization of chalcone synthase in grapevine (Vitis vinifera L.).

    PubMed

    Wang, Huiling; Wang, Wei; Zhan, JiCheng; Yan, Ailing; Sun, Lei; Zhang, Guojun; Wang, Xiaoyue; Ren, Jiancheng; Huang, Weidong; Xu, Haiying

    2016-09-01

    Chalcone synthase (CHS, E.C.2.3.1.74) is the first committed enzyme in the flavonoid pathway. Previous studies have primarily focused on the cloning, expression and regulation of the gene at the transcriptional level. Little is yet known about the enzyme accumulation, regulation at protein level, as well as its localization in grapevine. In present study, the accumulation, tissue and subcellular localization of CHS in different grapevine tissues (Vitis vinifera L. Cabernet Sauvignon) were investigated via the techniques of Western blotting, immunohistochemical localization, immunoelectron microscopy and confocal microscopy. The results showed that CHS were mainly accumulated in the grape berry skin, leaves, stem tips and stem phloem, correlated with flavonoids accumulation. The accumulation of CHS is developmental dependent in grape berry skin and flesh. Immunohistochemical analysis revealed that CHS were primarily localized in the exocarp and vascular bundles of the fruits during berry development; in palisade, spongy tissues and vascular bundles of the leaves; in the primary phloem and pith ray in the stems; in the growth point, leaf primordium, and young leaves of leaf buds; and in the endoderm and primary phloem of grapevine roots. Furthermore, at the subcellular level, the cell wall, cytoplasm and nucleus localized patterns of CHS were observed in the grapevine vegetative tissue cells. Results above indicated that distribution of CHS in grapevine was organ-specific and tissue-specific. This work will provide new insight for the biosynthesis and regulation of diverse flavonoid compounds in grapevine. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. LcMYB1 Is a Key Determinant of Differential Anthocyanin Accumulation among Genotypes, Tissues, Developmental Phases and ABA and Light Stimuli in Litchi chinensis

    PubMed Central

    Lai, Biao; Li, Xiao-Jing; Hu, Bing; Qin, Yong-Hua; Huang, Xu-Ming; Wang, Hui-Cong; Hu, Gui-Bing

    2014-01-01

    The red coloration of litchi fruit depends on the accumulation of anthocyanins. The anthocyanins level in litchi fruit varies widely among cultivars, developmental stages and environmental stimuli. Previous studies on various plant species demonstrate that anthocyanin biosynthesis is controlled at the transcriptional level. Here, we describe a litchi R2R3-MYB transcription factor gene, LcMYB1, which demonstrates a similar sequence as other known anthocyanin regulators. The transcription levels of the LcMYB1 and anthocyanin biosynthetic genes were investigated in samples with different anthocyanin levels. The expression of LcMYB1 was strongly associated with tissue anthocyanin content. LcMYB1 transcripts were only detected in anthocyanin-accumulating tissues and were positively correlated with anthocyanin accumulation in the pericarps of 12 genotypes. ABA and sunlight exposure promoted, whereas CPPU and bagging inhibited the expression of LcMYB1 and anthocyanin accumulation in the pericarp. Cis-elements associated with light responsiveness and abscisic acid responsiveness were identified in the promoter region of LcMYB1. Among the 6 structural genes tested, only LcUFGT was highly correlated with LcMYB1. These results suggest that LcMYB1 controls anthocyanin biosynthesis in litchi and LcUFGT might be the structural gene that is targeted and regulated by LcMYB1. Furthermore, the overexpression of LcMYB1 induced anthocyanin accumulation in all tissues in tobacco, confirming the function of LcMYB1 in the regulation of anthocyanin biosynthesis. The upregulation of NtAn1b in response to LcMYB1 overexpression seems to be essential for anthocyanin accumulation in the leaf and pedicel. In the reproductive tissues of transgenic tobacco, however, increased anthocyanin accumulation is independent of tobacco's endogenous MYB and bHLH transcriptional factors, but associated with the upregulation of specific structural genes. PMID:24466010

  11. Functionalization and Characterization of Magnetic Nanoparticles for the Detection of Ferritin Accumulation in Alzheimer's Disease.

    PubMed

    Fernández, Tamara; Martínez-Serrano, Alberto; Cussó, Lorena; Desco, Manuel; Ramos-Gómez, Milagros

    2018-05-16

    Early diagnosis in Alzheimer's disease (AD), prior to the appearance of marked clinical symptoms, is critical to prevent irreversible neuronal damage and neural malfunction that lead to dementia and death. Therefore, there is an urgent need to generate new contrast agents which reveal by a noninvasive method the presence of some of the pathological signs of AD. In the present study, we demonstrate for the first time a new nanoconjugate composed of magnetic nanoparticles bound to an antiferritin antibody, which has been developed based on the existence of iron deposits and high levels of the ferritin protein present in areas with a high accumulation of amyloid plaques (particularly the subiculum in the hippocampal area) in the brain of a transgenic mouse model with five familial AD mutations. Both in vitro and after intravenous injection, functionalized magnetic nanoparticles were able to recognize and bind specifically to the ferritin protein accumulated in the subiculum area of the AD transgenic mice.

  12. High-field penning-malmberg trap: confinement properties and use in positron accumulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartley, J.H.

    1997-09-01

    This dissertation reports on the development of the 60 kG cryogenic positron trap at Lawrence Livermore National Laboratory, and compares the trap`s confinement properties with other nonneutral plasma devices. The device is designed for the accumulation of up to 2{times}10{sup 9} positrons from a linear-accelerator source. This positron plasma could then be used in Bhabha scattering experiments. Initial efforts at time-of-flight accumulation of positrons from the accelerator show rapid ({approximately}100 ms) deconfinement, inconsistent with the long electron lifetimes. Several possible deconfinement mechanisms have been explored, including annihilation on residual gas, injection heating, rf noise from the accelerator, magnet field curvature,more » and stray fields. Detailed studies of electron confinement demonstrate that the empirical scaling law used to design the trap cannot be extrapolated into the parameter regime of this device. Several possible methods for overcoming these limitations are presented.« less

  13. Cadmium tolerance and accumulation of Elsholtzia argyi origining from a zinc/lead mining site - a hydroponics experiment.

    PubMed

    Li, Siliang; Wang, Fengping; Ru, Mei; Ni, Wuzhong

    2014-01-01

    In this study, a hydroponics experiment was conducted to investigate the characteristics of Cd tolerance and accumulation of Elsholtzia argyi natively growing on the soil with high levels of heavy metals in a Zn/Pb mining site. Seedlings of E. argyi grown for 4 weeks and then were treated with 0(CK), 5,10,15, 20, 25, 30, 40, 50,100 umM Cd for 21 days. Each treatment had three replications. No visual toxic symptoms on shoots of E. argyi were observed at Cd level < or = 50 muM. The results indicated that the dry biomass of each tissue and the whole plants of the treatments with < or =40 umM cadmium were similar to that of the control, implying that E. argyi was a cadmium tolerant plant. The results also showed that the shoot Cd concentration significantly (P < 0.05) increased with the increase in the Cd level in nutrient solution. The shoot Cd concentration of the treatment with 40 umM Cd was as high as 237.9 mg kg(-1), which was higher than 100 mg kg(-1), normally used as the threshold concentration for identifying the Cd hyperaccumulating plant. It could be concluded that E. argyi was a Cd tolerant and accumulating plant species.

  14. Heavy metal accumulation and source analysis in greenhouse soils of Wuwei District, Gansu Province, China.

    PubMed

    Bai, L Y; Zeng, X B; Su, S M; Duan, R; Wang, Y N; Gao, X

    2015-04-01

    Greenhouse soils and arable (wheat field) soil samples were collected to identify the effects of greenhouse cultivation on the accumulation of six heavy metals (Cd, Cu, Zn, Pb, Cr, and Ni) and to evaluate the likely sources responsible for heavy metal accumulation in the irrigated desert soils of Wuwei District, China. The results indicated that the mean concentrations of Cd, Cu, Zn, Pb, Cr, and Ni were 0.421, 33.85, 85.31, 20.76, 53.12, and 28.59 mg kg(-1), respectively. The concentrations of Cd, Cu, and Zn in greenhouse soils were 60, 23, and 14% higher than those in arable soils and 263, 40, and 25% higher than background concentrations of natural soils in the study area, respectively. These results indicated that Cd, Cu, and Zn accumulation occurred in the greenhouse soils, and Cd was the most problematically accumulated heavy metal, followed by Cu and Zn. There was a significant positive correlation between the concentrations of Cd, Cu, and Zn in greenhouse soils and the number of years under cultivation (P < 0.05). Greenhouse cultivation had little impact on the accumulation of Cr, Ni, or Pb. Correlation analysis and principal component analysis suggested that the accumulation of Cd, Cu, and Zn in greenhouse soils resulted mainly from fertilizer applications. Our results indicated that the excessive and long-term use of fertilizers and livestock manures with high heavy metal levels leads to the accumulation of heavy metals in soils. Therefore, rational fertilization programs and reductions in the concentrations of heavy metals in both fertilizers and manure must be recommended to maintain a safe concentration of heavy metals in greenhouse soils.

  15. cGMP accumulation causes photoreceptor degeneration in CNG channel deficiency: evidence of cGMP cytotoxicity independently of enhanced CNG channel function.

    PubMed

    Xu, Jianhua; Morris, Lynsie; Thapa, Arjun; Ma, Hongwei; Michalakis, Stylianos; Biel, Martin; Baehr, Wolfgang; Peshenko, Igor V; Dizhoor, Alexander M; Ding, Xi-Qin

    2013-09-11

    Photoreceptor cyclic nucleotide-gated (CNG) channels regulate Ca(2+) influx in rod and cone photoreceptors. cGMP, the native ligand of the photoreceptor CNG channels, has been associated with cytotoxicity when its levels rise above normal due to defects in photoreceptor phosphodiesterase (PDE6) or regulation of retinal guanylyl cyclase (retGC). We found a massive accumulation of cGMP in CNGA3-deficient retina and investigated whether cGMP accumulation plays a role in cone degeneration in CNG channel deficiency. The time course study showed that the retinal cGMP level in Cnga3(-/-);Nrl(-/-) mice with CNGA3 deficiency on a cone-dominant background was sharply increased at postnatal day 8 (P8), peaked around P10-P15, remained high through P30-P60, and returned to near control level at P90. This elevation pattern correlated with photoreceptor apoptotic death, which peaked around P15-P20. In Cnga3(-/-);Gucy2e(-/-) mice lacking retGC1, cone density and expression levels of cone-specific proteins were significantly increased compared with Cnga3(-/-), consistent with a role of cGMP accumulation as the major contributor to cone death caused by CNG channel deficiency. The activity and expression levels of cGMP-dependent protein kinase G (PKG) were significantly increased in Cnga3(-/-);Nrl(-/-) retina compared with Nrl(-/-), suggesting an involvement of PKG regulation in cell death. Our results indicate that cGMP accumulation in photoreceptors can itself exert cytotoxic effect in cones, independently of CNG channel activity and Ca(2+) influx.

  16. Exogenous Methyl Jasmonate and Salicylic Acid Induce Subspecies-Specific Patterns of Glucosinolate Accumulation and Gene Expression in Brassica oleracea L.

    PubMed

    Yi, Go-Eun; Robin, Arif Hasan Khan; Yang, Kiwoung; Park, Jong-In; Hwang, Byung Ho; Nou, Ill-Sup

    2016-10-24

    Glucosinolates have anti-carcinogenic properties. In the recent decades, the genetics of glucosinolate biosynthesis has been widely studied, however, the expression of specific genes involved in glucosinolate biosynthesis under exogenous phytohormone treatment has not been explored at the subspecies level in Brassica oleracea . Such data are vital for strategies aimed at selective exploitation of glucosinolate profiles. This study quantified the expression of 38 glucosinolate biosynthesis-related genes in three B. oleracea subspecies, namely cabbage, broccoli and kale, and catalogued associations between gene expression and increased contents of individual glucosinolates under methyl jasmonate (MeJA) and salicylic acid (SA) treatments. Glucosinolate accumulation and gene expression in response to phytohormone elicitation was subspecies specific. For instance, cabbage leaves showed enhanced accumulation of the aliphatic glucoiberin, progoitrin, sinigrin and indolic neoglucobrassicin under both MeJA and SA treatment. MeJA treatment induced strikingly higher accumulation of glucobrassicin (GBS) in cabbage and kale and of neoglucobrassicin (NGBS) in broccoli compared to controls. Notably higher expression of ST5a (Bol026200), CYP81F1 (Bol028913, Bol028914) and CYP81F4 genes was associated with significantly higher GBS accumulation under MeJA treatment compared to controls in all three subspecies. CYP81F4 genes, trans-activated by MYB34 genes, were expressed at remarkably high levels in all three subspecies under MeJA treatment, which also induced in higher indolic NGBS accumulation in all three subspecies. Remarkably higher expression of MYB28 (Bol036286), ST5b , ST5c , AOP2 , FMOGS-OX5 (Bol031350) and GSL-OH (Bol033373) was associated with much higher contents of aliphatic glucosinolates in kale leaves compared to the other two subspecies. The genes expressed highly could be utilized in strategies to selectively increase glucosinolate compounds in B. oleracea

  17. Blood lactate accumulation in top level swimmers following competition.

    PubMed

    Bonifazi, M; Martelli, G; Marugo, L; Sardella, F; Carli, G

    1993-03-01

    The purposes of this study were to evaluate the significance of blood lactate values after competitions and the blood lactate-swimming speed relationship to swimming performances. Auricular blood samples (N = 421) were collected in 203 top level Italian swimmers (116 males and 87 females) at the end of competitions performed in a 25 m swimming pool. The distribution of all lactate values differed between males and females. The lowest lactate values occurred in swimmers performing the longest distances both in males (1500 m) and females (800 m). In swimmers performing freestyle events a relationship between V-4 mM (swimming speed at 4 mmol/l blood lactate value) and competition velocities was observed, in males, at 200, 400 and 1500 m and, in females, at 400 and 800 m. The predicted velocity corresponding to the competition lactate value assessed by the individual blood lactate-swimming speed relationship was found to be highly related to the actual competition velocity. Results suggest that blood lactate values in swimmers are a useful indication of individual aptitudes.

  18. Carbon and nitrogen accumulation and fluxes on Landscape Evolution Observatory (LEO) slopes

    NASA Astrophysics Data System (ADS)

    Dontsova, K.; Volk, M.; Webb, C.; Hunt, E.; Tfaily, M. M.; Van Haren, J. L. M.; Sengupta, A.; Chorover, J.; Troch, P.; Ruiz, J.

    2017-12-01

    Carbon accumulation on the landscapes in organic and inorganic forms is an important sink of CO2 from the atmosphere. Formation and preservation of organic compounds is accompanied by N fixation from the atmosphere and cycling in the soil. Model slopes of Landscape Evolution Observatory present unique opportunity to examine carbon and nitrogen buildup on the landscapes during soil formation processes, such as weathering of primary minerals and microbial activity, due to low original levels of C and N, tight control over environmental conditions, and high spatial and temporal density of measurements. This presents results of inorganic and organic C and N measurements in the cores collected in LEO slopes after several years of exposure to the rainfall, as well as soil solution measurements collected through 496 samplers on each of three model slopes and in seepage. We observed significant spatially distributed accumulation of both C (organic and inorganic) and N in soil profiles. We also observed differences in the composition of organic compounds in the solid and solution phases depending on location on the slope indicating formation of heterogeneity as soils develop. This works indicates potential of physical models to help understand accumulation and fluxes of C and N on natural landscapes.

  19. Targeted Nanocurcumin Therapy Using Annexin A2 Anitbody Improves Tumor Accumulation and Therapeutic Efficacy Against Highly Metastatic Breast Cancer.

    PubMed

    Mukerjee, Anindita; Ranjan, Anmalendu P; Vishwanatha, Jamboor K

    2016-07-01

    A major challenge in pharmaceutical research is effective targeting strategies to their sites of action. Emerging knowledge and the current progress in nanotechnology based delivery systems has opened up exciting ways towards successful targeted nanodelivery systems. For cancer therapy, nanoparticle-based drug formulations hold several advantages over free drugs, including improved pharmacokinetics, enhanced tumor accumulation, reduced systemic exposure and side effects and better patient compliance. The goal of this study was to validate the in vivo targeting potential and evaluate the combinatorial therapeutic potential of novel Annexin A2 (AnxA2) antibody-conjugated curcumin loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (AnxA2-CPNP) against metastatic breast cancer. As a first step, we demonstrated that the cell-surface expression of AnxA2 is increases during breast cancer progression with very high expression in highly malignant cancer cells and basal expression in non-malignant cells. This confirmed AnxA2 as an excellent target for targeting our curcumin nanoparticles. Our results indicate that AnxA2-CPNP showed increased uptake in highly metastatic breast cancer cells than untargeted nanoparticles due to the differential AnxA2 expression. Cell viability, plasmin generation and wound healing assays reveal that AnxA2-CPNPs effectively inhibited cell proliferation, invasion and migration, key elements for cancer growth and metastasis. Further, angiogenesis assay illustrated that AnxA2-CPNPs decreased the formation of tube capillaries, thus inhibiting neoangiogenesis, a critical element in tumor growth. Live animal imaging demonstrated that AnxA2-PNPs and AnxA2-CPNPs effectively targeted and accumulated in the tumor as seen by the increased fluorescence intensity on the live scans. Xenograft studies in mice showed significant regression of breast tumor as a result of both effective targeting, accumulation and sustained release of curcumin in the tumor

  20. Hamming and Accumulator Codes Concatenated with MPSK or QAM

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel

    2009-01-01

    In a proposed coding-and-modulation scheme, a high-rate binary data stream would be processed as follows: 1. The input bit stream would be demultiplexed into multiple bit streams. 2. The multiple bit streams would be processed simultaneously into a high-rate outer Hamming code that would comprise multiple short constituent Hamming codes a distinct constituent Hamming code for each stream. 3. The streams would be interleaved. The interleaver would have a block structure that would facilitate parallelization for high-speed decoding. 4. The interleaved streams would be further processed simultaneously into an inner two-state, rate-1 accumulator code that would comprise multiple constituent accumulator codes - a distinct accumulator code for each stream. 5. The resulting bit streams would be mapped into symbols to be transmitted by use of a higher-order modulation - for example, M-ary phase-shift keying (MPSK) or quadrature amplitude modulation (QAM). The novelty of the scheme lies in the concatenation of the multiple-constituent Hamming and accumulator codes and the corresponding parallel architectures of the encoder and decoder circuitry (see figure) needed to process the multiple bit streams simultaneously. As in the cases of other parallel-processing schemes, one advantage of this scheme is that the overall data rate could be much greater than the data rate of each encoder and decoder stream and, hence, the encoder and decoder could handle data at an overall rate beyond the capability of the individual encoder and decoder circuits.

  1. MicroRNA166 Modulates Cadmium Tolerance and Accumulation in Rice.

    PubMed

    Ding, Yanfei; Gong, Shaohua; Wang, Yi; Wang, Feijuan; Bao, Hexigeduleng; Sun, Junwei; Cai, Chong; Yi, Keke; Chen, Zhixiang; Zhu, Cheng

    2018-06-20

    MicroRNAs (miRNAs) are 20- to 24-nucleotide small non-coding RNAs that regulate gene expression in eukaryotic organisms. Several plant miRNAs, such as miR166, have vital roles in plant growth, development and responses to environmental stresses. One such environmental stress encountered by crop plants is exposure to cadmium (Cd), an element highly toxic to most organisms, including humans and plants. In this study, we analyzed the role of miR166 in Cd accumulation and tolerance in rice (Oryza sativa). The expression levels of miR166 in both root and leaf tissues were significantly higher in the reproductive stage than in the seedling stage in rice. The expression of miR166 in the roots of rice seedlings was reduced after Cd treatment. Overexpression of miR166 in rice improved Cd tolerance, a result associated with the reduction of Cd-induced oxidative stress in transgenic rice plants. Furthermore, overexpression of miR166 reduced both Cd translocation from roots to shoots and Cd accumulation in the grains. miR166 targets genes encoding the class-III homeodomain-leucine zipper (HD-Zip) family proteins in plants. In rice, HOMEODOMAIN CONTAINING PROTEIN 4 (OsHB4) gene (Os03g43930), which encodes an HD-Zip protein, was up-regulated by Cd treatment but down-regulated by overexpression of miR166 in transgenic rice plants. Overexpression of OsHB4 increased Cd sensitivity and Cd accumulation in the leaves and grains of transgenic rice plants. By contrast, silencing OsHB4 by RNA interference enhanced Cd tolerance in transgenic rice plants. These results indicate a critical role for miR166 in Cd accumulation and tolerance through regulation of its target gene, OsHB4, in rice. {copyright, serif} 2018 American Society of Plant Biologists. All rights reserved.

  2. Using proteomic analysis to investigate uniconazole-induced phytohormone variation and starch accumulation in duckweed (Landoltia punctata).

    PubMed

    Huang, Mengjun; Fang, Yang; Liu, Yang; Jin, Yanling; Sun, Jiaolong; Tao, Xiang; Ma, Xinrong; He, Kaize; Zhao, Hai

    2015-09-15

    Duckweed (Landoltia punctata) has the potential to remediate wastewater and accumulate enormous amounts of starch for bioethanol production. Using systematical screening, we determined that the highest biomass and starch percentage of duckweed was obtained after uniconazole application. Uniconazole contributes to starch accumulation of duckweed, but the molecular mechanism is still unclear. To elucidate the mechanisms of high starch accumulation, in the study, the responses of L. punctata to uniconazole were investigated using a quantitative proteomic approach combined with physiological and biochemical analysis. A total of 3327 proteins were identified. Among these identified proteins, a large number of enzymes involved in endogenous hormone synthetic and starch metabolic pathways were affected. Notably, most of the enzymes involved in abscisic acid (ABA) biosynthesis showed up-regulated expression, which was consistent with the content variation. The increased endogenous ABA may up-regulate expression of ADP-glucose pyrophosphorylase to promote starch biosynthesis. Importantly, the expression levels of several key enzymes in the starch biosynthetic pathway were up-regulated, which supported the enzymatic assay results and may explain why there is increased starch accumulation. These generated data linked uniconazole with changes in expression of enzymes involved in hormone biosynthesis and starch metabolic pathways and elucidated the effect of hormones on starch accumulation. Thus, this study not only provided insights into the molecular mechanisms of uniconazole-induced hormone variation and starch accumulation but also highlighted the potential for duckweed to be feedstock for biofuel as well as for sewage treatment.

  3. Drug accumulation by means of noninvasive magnetic drug delivery system

    NASA Astrophysics Data System (ADS)

    Chuzawa, M.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2011-11-01

    The medication is one of the most general treatment methods, but drugs diffuse in the normal tissues other than the target part by the blood circulation. Therefore, side effect in the medication, particularly for a drug with strong effect such as anti-cancer drug, are a serious issue. Drug Delivery System (DDS) which accumulates the drug locally in the human body is one of the techniques to solve the side-effects. Magnetic Drug Delivery System (MDDS) is one of the active DDSs, which uses the magnetic force. The objective of this study is to accumulate the ferromagnetic drugs noninvasively in the deep part of the body by using MDDS. It is necessary to generate high magnetic field and magnetic gradient at the target part to reduce the side-effects to the tissues with no diseases. The biomimetic model was composed, which consists of multiple model organs connected with diverged blood vessel model. The arrangement of magnetic field was examined to accumulate ferromagnetic drug particles in the target model organ by using a superconducting bulk magnet which can generate high magnetic fields. The arrangement of magnet was designed to generate high and stable magnetic field at the target model organ. The accumulation experiment of ferromagnetic particles has been conducted. In this study, rotating HTS bulk magnet around the axis of blood vessels by centering on the target part was suggested, and the model experiment for magnet rotation was conducted. As a result, the accumulation of the ferromagnetic particles to the target model organ in the deep part was confirmed.

  4. Divide and conquer: intermediate levels of population fragmentation maximize cultural accumulation.

    PubMed

    Derex, Maxime; Perreault, Charles; Boyd, Robert

    2018-04-05

    Identifying the determinants of cumulative cultural evolution is a key issue in the interdisciplinary field of cultural evolution. A widely held view is that large and well-connected social networks facilitate cumulative cultural evolution because they promote the spread of useful cultural traits and prevent the loss of cultural knowledge through factors such as drift. This view stems from models that focus on the transmission of cultural information, without considering how new cultural traits actually arise. In this paper, we review the literature from various fields that suggest that, under some circumstances, increased connectedness can decrease cultural diversity and reduce innovation rates. Incorporating this idea into an agent-based model, we explore the effect of population fragmentation on cumulative culture and show that, for a given population size, there exists an intermediate level of population fragmentation that maximizes the rate of cumulative cultural evolution. This result is explained by the fact that fully connected, non-fragmented populations are able to maintain complex cultural traits but produce insufficient variation and so lack the cultural diversity required to produce highly complex cultural traits. Conversely, highly fragmented populations produce a variety of cultural traits but cannot maintain complex ones. In populations with intermediate levels of fragmentation, cultural loss and cultural diversity are balanced in a way that maximizes cultural complexity. Our results suggest that population structure needs to be taken into account when investigating the relationship between demography and cumulative culture.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

  5. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Bilge high level alarms. 182.530 Section 182.530... TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a... operating station to indicate a high water level in each of the following normally unmanned spaces: (1) A...

  6. Adaptive History Biases Result from Confidence-Weighted Accumulation of past Choices

    PubMed Central

    2018-01-01

    Perceptual decision-making is biased by previous events, including the history of preceding choices: observers tend to repeat (or alternate) their judgments of the sensory environment more often than expected by chance. Computational models postulate that these so-called choice history biases result from the accumulation of internal decision signals across trials. Here, we provide psychophysical evidence for such a mechanism and its adaptive utility. Male and female human observers performed different variants of a challenging visual motion discrimination task near psychophysical threshold. In a first experiment, we decoupled categorical perceptual choices and motor responses on a trial-by-trial basis. Choice history bias was explained by previous perceptual choices, not motor responses, highlighting the importance of internal decision signals in action-independent formats. In a second experiment, observers performed the task in stimulus environments containing different levels of autocorrelation and providing no external feedback about choice correctness. Despite performing under overall high levels of uncertainty, observers adjusted both the strength and the sign of their choice history biases to these environments. When stimulus sequences were dominated by either repetitions or alternations, the individual degree of this adjustment of history bias was about as good a predictor of individual performance as individual perceptual sensitivity. The history bias adjustment scaled with two proxies for observers' confidence about their previous choices (accuracy and reaction time). Together, our results are consistent with the idea that action-independent, confidence-modulated decision variables are accumulated across choices in a flexible manner that depends on decision-makers' model of their environment. SIGNIFICANCE STATEMENT Decisions based on sensory input are often influenced by the history of one's preceding choices, manifesting as a bias to systematically repeat

  7. Adaptive History Biases Result from Confidence-weighted Accumulation of Past Choices.

    PubMed

    Braun, Anke; Urai, Anne E; Donner, Tobias H

    2018-01-25

    Perceptual decision-making is biased by previous events, including the history of preceding choices: Observers tend to repeat (or alternate) their judgments of the sensory environment more often than expected by chance. Computational models postulate that these so-called choice history biases result from the accumulation of internal decision signals across trials. Here, we provide psychophysical evidence for such a mechanism and its adaptive utility. Male and female human observers performed different variants of a challenging visual motion discrimination task near psychophysical threshold. In a first experiment, we decoupled categorical perceptual choices and motor responses on a trial-by-trial basis. Choice history bias was explained by previous perceptual choices, not motor responses, highlighting the importance of internal decision signals in action-independent formats. In a second experiment, observers performed the task in stimulus environments containing different levels of auto-correlation and providing no external feedback about choice correctness. Despite performing under overall high levels of uncertainty, observers adjusted both the strength and the sign of their choice history biases to these environments. When stimulus sequences were dominated by either repetitions or alternations, the individual degree of this adjustment of history bias was about as good a predictor of individual performance as individual perceptual sensitivity. The history bias adjustment scaled with two proxies for observers' confidence about their previous choices (accuracy and reaction time). Taken together, our results are consistent with the idea that action-independent, confidence-modulated decision variables are accumulated across choices in a flexible manner that depends on decision-makers' model of their environment. Significance statement: Decisions based on sensory input are often influenced by the history of one's preceding choices, manifesting as a bias to

  8. Ursolic acid, a natural pentacyclic triterpenoid, inhibits intracellular trafficking of proteins and induces accumulation of intercellular adhesion molecule-1 linked to high-mannose-type glycans in the endoplasmic reticulum

    PubMed Central

    Mitsuda, Satoshi; Yokomichi, Tomonobu; Yokoigawa, Junpei; Kataoka, Takao

    2014-01-01

    Ursolic acid (3β-hydroxy-urs-12-en-28-oic acid) is a natural pentacyclic triterpenoid that is present in many plants, including medicinal herbs, and foods. Ursolic acid was initially identified as an inhibitor of the expression of intercellular adhesion molecule-1 (ICAM-1) in response to interleukin-1α (IL-1α). We report here a novel biological activity: ursolic acid inhibits intracellular trafficking of proteins. Ursolic acid markedly inhibited the IL-1α-induced cell-surface ICAM-1 expression in human cancer cell lines and human umbilical vein endothelial cells. By contrast, ursolic acid exerted weak inhibitory effects on the IL-1α-induced ICAM-1 expression at the protein level. Surprisingly, we found that ursolic acid decreased the apparent molecular weight of ICAM-1 and altered the structures of N-linked oligosaccharides bound to ICAM-1. Ursolic acid induced the accumulation of ICAM-1 in the endoplasmic reticulum, which was linked mainly to high-mannose-type glycans. Moreover, in ursolic-acid-treated cells, the Golgi apparatus was fragmented into pieces and distributed over the cells. Thus, our results reveal that ursolic acid inhibits intracellular trafficking of proteins and induces the accumulation of ICAM-1 linked to high-mannose-type glycans in the endoplasmic reticulum. PMID:24649404

  9. Dietary cholesterol worsens adipose tissue macrophage accumulation and atherosclerosis in obese LDL receptor-deficient mice

    PubMed Central

    Subramanian, Savitha; Han, Chang Yeop; Chiba, Tsuyoshi; McMillen, Timothy S.; Wang, Shari A.; Haw, Antonio; Kirk, Elizabeth A.; O’Brien, Kevin D.; Chait, Alan

    2009-01-01

    Objective Chronic systemic inflammation accompanies obesity and predicts development of cardiovascular disease. Dietary cholesterol has been shown to increase inflammation and atherosclerosis in LDL receptor-deficient (LDLR-/-) mice. This study was undertaken to determine whether dietary cholesterol and obesity have additive effects on inflammation and atherosclerosis. Methods and Results LDLR-/- mice were fed chow, high fat, high carbohydrate (diabetogenic) diet without (DD) or with added cholesterol (DDC) for 24 weeks. Effects on adipose tissue, inflammatory markers and atherosclerosis were studied. Despite similar weight gain between DD and DDC groups, addition of dietary cholesterol increased insulin resistance relative to DD. Adipocyte hypertrophy, macrophage accumulation and local inflammation were observed in intra-abdominal adipose tissue in DD and DDC, but were significantly higher in the DDC group. Circulating levels of the inflammatory protein serum amyloid A (SAA) were 4.4-fold higher in DD animals and 15-fold higher in DDC animals than controls, suggesting chronic systemic inflammation. Hepatic SAA mRNA levels were similarly elevated. Atherosclerosis was increased in the DD-fed animals and further increased in the DDC group. Conclusions Obesity-induced macrophage accumulation in adipose tissue is exacerbated by dietary cholesterol. These local inflammatory changes in adipose tissue are associated with insulin resistance, systemic inflammation and increased atherosclerosis in this mouse model. PMID:18239153

  10. Role of splenic reservoir monocytes in pulmonary vascular monocyte accumulation in experimental hepatopulmonary syndrome

    PubMed Central

    Wu, Wei; Zhang, Junlan; Yang, Wenli; Hu, Bingqian

    2016-01-01

    Abstract Background and Aim Pulmonary monocyte infiltration plays a significant role in the development of angiogenesis in experimental hepatopulmonary syndrome (HPS) after common bile duct ligation (CBDL). Hepatic monocytes are also increased after CBDL, but the origins remain unclear. Splenic reservoir monocytes have been identified as a major source of monocytes that accumulate in injured tissues. Whether splenic monocytes contribute to monocyte alterations after CBDL is unknown. This study evaluates monocyte distributions and assesses effects of splenectomy on monocyte levels and pulmonary vascular and hepatic abnormalities in experimental HPS. Methods Splenectomy was performed in CBDL animals. Monocyte levels in different tissues and circulation were assessed with CD68. Pulmonary alterations of HPS were evaluated with vascular endothelial growth factor‐A (VEGF‐A) levels, angiogenesis, and alveolar–arterial oxygen gradient (AaPO2). Liver abnormalities were evaluated with fibrosis (Sirius red), bile duct proliferation (CK‐19), and enzymatic changes. Results Monocyte levels increased in the lung and liver after CBDL and were accompanied by elevated circulating monocyte numbers. Splenectomy significantly decreased monocyte accumulation, VEGF‐A levels, and angiogenesis in CBDL animal lung and improved AaPO2 levels. In contrast, hepatic monocyte levels, fibrosis, and functional abnormalities were further exacerbated by spleen removal. Conclusions Splenic reservoir monocytes are a major source for lung monocyte accumulation after CBDL, and spleen removal attenuates the development of experimental HPS. Liver monocytes may have different origins, and accumulation is exacerbated after depletion of splenic reservoir monocytes. Tissue specific monocyte alterations, influenced by the spleen reservoir, have a significant impact on pulmonary complications of liver disease. PMID:27029414

  11. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the following...

  12. Predictors of Placement in Lower Level versus Higher Level High School Mathematics

    ERIC Educational Resources Information Center

    Archbald, Doug; Farley-Ripple, Elizabeth N.

    2012-01-01

    Educators and researchers have long been interested in determinants of access to honors level and college prep courses in high school. Factors influencing access to upper level mathematics courses are particularly important because of the hierarchical and sequential nature of this subject and because students who finish high school with only lower…

  13. High levels of Porphyromonas gingivalis-induced immunoglobulin G2 are associated with lower high-density lipoprotein levels in chronic periodontitis.

    PubMed

    Ardila, Carlos M; Guzmán, Isabel C

    2016-11-01

    To investigate the association between the presence of Porphyromonas gingivalis-induced immunoglobulin G antibodies and the high-density lipoprotein (HDL) level. A total of 108 individuals were examined. The presence of P. gingivalis was detected using primers designed to target the 16S rRNA gene sequence. Peripheral blood was collected from each subject to determine the levels of P. gingivalis-induced IgG1 and IgG2 serum antibodies. The HDL levels were determined using fully enzymatic methods. A higher proportion of periodontitis patients had high levels of P. gingivalis-induced IgG1 and IgG2, and the proportion of subjects with a HDL level of < 35 md/dL was higher in the group of chronic periodontitis patients. In the unadjusted regression model, the presence of high levels of P. gingivalis-induced IgG2 was associated with a HDL level of < 35 md/dL. The adjusted model indicated that periodontitis patients with high levels of P. gingivalis-induced IgG2 showed 3.2 more chances of having pathological HDL levels (odds ratio = 3.2, 95% confidence interval = 1.2-9.8). High levels of P. gingivalis-induced IgG2 were associated with low HDL concentrations in patients with periodontitis, which suggests that the response of the host to periodontal infection may play an important role in the pathogenesis of cardiovascular diseases. © 2015 Wiley Publishing Asia Pty Ltd.

  14. Temporal and spatial changes in ion homeostasis, antioxidant defense and accumulation of flavonoids and glycolipid in a halophyte Sesuvium portulacastrum (L.) L.

    PubMed Central

    Nikalje, Ganesh C.; Variyar, P. S.; Joshi, M. V.; Nikam, T. D.

    2018-01-01

    Salinity is an important environmental constraint limiting plant productivity. Understanding adaptive responses of halophytes to high saline environments may offer clues to manage and improve salt stress in crop plants. We have studied physiological, biochemical and metabolic changes in a perennial, fast growing halophyte, Sesuvium portulacastrum under 0 mM (control), 150 mM (low salt, LS) and 500 mM (high salt, HS) NaCl treatments. The changes in growth, relative water content, cation, osmolyte accumulation, H2O2 and antioxidant enzyme activity (SOD, CAT and APX) were observed under different treatment conditions. A positive correlation was revealed for sodium ion accumulation with malondialdehyde (r2 = 0.77), proline (r2 = 0.88) and chlorophyll content (r2 = 0.82) under salt treatment while a negative correlation was observed with relative tissue water content (r2 = -0.73). The roots and leaves showed contrasting accumulation of potassium and sodium ions under LS treatment. Temporal and spatial study of sodium and potassium ion content indicated differential accumulation pattern in roots and leaves, and, high potassium levels in root. Higher H2O2 content was recorded in roots than leaves and the antioxidant enzyme activities also showed significant induction under salt treatment conditions. Gene expression profiling of sodium transporters, Sodium proton exchanger (NHX3), Vacuolar ATPase (vATPase) and Salt overly sensitive1 (SOS1) showed up regulation under salt stress after 6–24 hr of NaCl treatment. Metabolite changes in the salt stressed leaves showed increased accumulation of flavonoids (3,5-dihydroxy-6,4’-dimethoxy-flavone-7-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside], and3,5-dihydroxy-6,3’,4’-trimethoxy-flavone-7-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside] in both LS and HS treatments, while a glycolipid, 1-O-linolenyl-2-O-(palmitoyl)-3-O-galactopyranosyl glycerol, accumulated more in LS over HS treatments and control. The results

  15. Accumulation of kaempferitrin and expression of phenyl-propanoid biosynthetic genes in kenaf (Hibiscus cannabinus).

    PubMed

    Zhao, Shicheng; Li, Xiaohua; Cho, Dong Ha; Arasu, Mariadhas Valan; Al-Dhabi, Naif Abdullah; Park, Sang Un

    2014-10-23

    Kenaf (Hibiscus cannabinus) is cultivated worldwide for its fiber; however, the medicinal properties of this plant are currently attracting increasing attention. In this study, we investigated the expression levels of genes involved in the biosynthesis of kaempferitrin, a compound with many biological functions, in different kenaf organs. We found that phenylalanine ammonia lyase (HcPAL) was more highly expressed in stems than in other organs. Expression levels of cinnamate 4-hydroxylase (HcC4H) and 4-coumarate-CoA ligase (Hc4CL) were highest in mature leaves, followed by stems and young leaves, and lowest in roots and mature flowers. The expression of chalcone synthase (HcCHS), chalcone isomerase (HcCHI), and flavone 3-hydroxylase (HcF3H) was highest in young flowers, whereas that of flavone synthase (HcFLS) was highest in leaves. An analysis of kaempferitrin accumulation in the different organs of kenaf revealed that the accumulation of this compound was considerably higher (>10-fold) in leaves than in other organs. On the basis of a comparison of kaempferitrin contents with the expression levels of different genes in different organs, we speculate that HcFLS plays an important regulatory role in the kaempferitrin biosynthetic pathway in kenaf.

  16. The influence of salinity on copper accumulation and its toxic effects in estuarine animals with differing osmoregulatory strategies.

    PubMed

    Lee, Jacqueline A; Marsden, Islay D; Glover, Chris N

    2010-08-01

    Copper is an important ionoregulatory toxicant in freshwater, but its effects in marine and brackish water systems are less well characterised. The effect of salinity on short-term copper accumulation and sublethal toxicity in two estuarine animals was investigated. The osmoregulating crab Hemigrapsus crenulatus accumulated copper in a concentration-dependent, but salinity-independent manner. Branchial copper accumulation correlated positively with branchial sodium accumulation. Sublethal effects of copper were most prevalent in 125% seawater, with a significant increase in haemolymph chloride noted after 96h at exposure levels of 510 microg Cu(II) L(-1). The osmoconforming gastropod, Scutus breviculus, was highly sensitive to copper exposure, a characteristic recognised previously in related species. Toxicity, as determined by a behavioural index, was present at all salinities and was positively correlated with branchial copper accumulation. At 100% seawater, increased branchial sodium accumulation, decreased haemolymph chloride and decreased haemolymph osmolarity were observed after 48h exposure to 221 microg Cu(II) L(-1), suggesting a mechanism of toxicity related to ionoregulation. However, these effects were likely secondary to a general effect on gill barrier function, and possibly mediated by mucus secretion. Significant impacts of copper on haemocyanin were also noted in both animals, highlighting a potentially novel mechanism of copper toxicity to animals utilising this respiratory pigment. Overall these findings indicate that physiology, as opposed to water chemistry, exerts the greatest influence over copper toxicity. An understanding of the physiological limits of marine and estuarine organisms may be critical for calibration of predictive models of metal toxicity in waters of high and fluctuating salinities. Copyright 2010 Elsevier B.V. All rights reserved.

  17. High-Level Radioactive Waste.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  18. Absence of ppGpp Leads to Increased Mobilization of Intermediately Accumulated Poly(3-Hydroxybutyrate) in Ralstonia eutropha H16

    PubMed Central

    Juengert, Janina R.; Borisova, Marina; Wolz, Christiane; Brigham, Christopher J.; Sinskey, Anthony J.

    2017-01-01

    ABSTRACT In this study, we constructed a set of Ralstonia eutropha H16 strains with single, double, or triple deletions of the (p)ppGpp synthase/hydrolase (spoT1), (p)ppGpp synthase (spoT2), and/or polyhydroxybutyrate (PHB) depolymerase (phaZa1 or phaZa3) gene, and we determined the impact on the levels of (p)ppGpp and on accumulated PHB. Mutants with deletions of both the spoT1 and spoT2 genes were unable to synthesize detectable amounts of (p)ppGpp and accumulated only minor amounts of PHB, due to PhaZa1-mediated depolymerization of PHB. In contrast, unusually high levels of PHB were found in strains in which the (p)ppGpp concentration was increased by the overexpression of (p)ppGpp synthase (SpoT2) and the absence of (p)ppGpp hydrolase. Determination of (p)ppGpp levels in wild-type R. eutropha under different growth conditions and induction of the stringent response by amino acid analogs showed that the concentrations of (p)ppGpp during the growth phase determine the amount of PHB remaining in later growth phases by influencing the efficiency of the PHB mobilization system in stationary growth. The data reported for a previously constructed ΔspoT2 strain (C. J. Brigham, D. R. Speth, C. Rha, and A. J. Sinskey, Appl Environ Microbiol 78:8033–8044, 2012, https://doi.org/10.1128/AEM.01693-12) were identified as due to an experimental error in strain construction, and our results are in contrast to the previous indication that the spoT2 gene product is essential for PHB accumulation in R. eutropha. IMPORTANCE Polyhydroxybutyrate (PHB) is an important intracellular carbon and energy storage compound in many prokaryotes and helps cells survive periods of starvation and other stress conditions. Research activities in several laboratories over the past 3 decades have shown that both PHB synthase and PHB depolymerase are constitutively expressed in most PHB-accumulating bacteria, such as Ralstonia eutropha. This implies that PHB synthase and depolymerase activities

  19. Endophytic bacterium Sphingomonas SaMR12 promotes cadmium accumulation by increasing glutathione biosynthesis in Sedum alfredii Hance.

    PubMed

    Pan, Fengshan; Meng, Qian; Wang, Qiong; Luo, Sha; Chen, Bao; Khan, Kiran Yasmin; Yang, Xiaoe; Feng, Ying

    2016-07-01

    A hydroponic experiment was conducted to verify the effects of inoculation with endophytic bacteria Sphingomonas SaMR12 on root growth, cadmium (Cd) uptake, reactive oxygen species (ROS), antioxidases, glutathione (GSH) and the related gene expression of Sedum alfredii Hance under different levels of Cd such as 0, 10, 25, 100 and 400 μM. The results showed that inoculation of SaMR12 improved Cd accumulation and upregulated glutathione synthase (GS) expression, but slightly reduced malondialdehyde (MDA) concentration and alleviated Cd-induced damage in roots. However it didn't alter the activities of antioxidant enzymes. When Cd concentration exceeded 25 μM, SaMR12 increased the concentration of GSH and the expression level of GSH1. At high Cd treatment levels (100 and 400 μM), SaMR12 significantly reduced H2O2 concentration and enhanced expression level of 1-Cys peroxiredoxin PER1 and ATPS genes. These results indicate that although SaMR12 has no significant effects on antioxidases activities, it reduces H2O2 concentration by enhancing GSH concentration and relevant genes expression, and subsequently improves Cd tolerance and accumulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Accumulation of contaminants of emerging concern in food crops-part 1: Edible strawberries and lettuce grown in reclaimed water.

    PubMed

    Hyland, Katherine C; Blaine, Andrea C; Dickenson, Eric R V; Higgins, Christopher P

    2015-10-01

    Contaminants of emerging concern present in domestic waste streams include a highly diverse group of potentially biologically active compounds that can be detected at trace levels in wastewater. Concerns about potential uptake into crops arise when reclaimed water is used in food crop production. The present study investigated how 9 contaminants of emerging concern in reclaimed water are taken up into edible portions of two food crops. Two flame retardant chemicals, tris(1-chloro-2-propyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) and several polar pharmaceuticals (carbamazepine, diphenhydramine, sulfamethoxazole, and trimethoprim) accumulated in a linear, concentration-dependent manner in lettuce (Lactuca sativa) irrigated with reclaimed water, suggesting passive uptake of both neutral and ionizable chemical contaminants in lettuce. Furthermore, concentration-dependent accumulation of TCEP and TCPP from reclaimed water was also observed in strawberry fruits (Fragaria ananassa). Collectively, these data suggest that highly polar or charged contaminants can be taken up by crops from water bearing contaminants of emerging concern and can be accumulated in the edible portions. Using these data, however, estimates of human exposure to these contaminants from reclaimed water food crop accumulation suggest that exposure to the contaminants of emerging concern examined in the present study is likely substantially lower than current exposure guidelines. © 2015 SETAC.

  1. Engineering α-amylase levels in wheat grain suggests a highly sophisticated level of carbohydrate regulation during development.

    PubMed

    Whan, Alex; Dielen, Anne-Sophie; Mieog, Jos; Bowerman, Andrew F; Robinson, Hannah M; Byrne, Keren; Colgrave, Michelle; Larkin, Philip J; Howitt, Crispin A; Morell, Matthew K; Ral, Jean-Philippe

    2014-10-01

    Wheat starch degradation requires the synergistic action of different amylolytic enzymes. Our spatio-temporal study of wheat α-amylases throughout grain development shows that AMY3 is the most abundant isoform compared with the other known α-amylases. Endosperm-specific over-expression of AMY3 resulted in an increase of total α-amylase activity in harvested grains. Unexpectedly, increased activity did not have a significant impact on starch content or composition but led to an increase of soluble carbohydrate (mainly sucrose) in dry grain. In AMY3 overexpression lines (A3OE), germination was slightly delayed and triacylglycerol (TAG) content was increased in the endosperm of mature grain. Despite increased AMY3 transcript and protein content throughout grain development, alterations of α-amylase activity and starch granule degradation were not detected until grain maturation, suggesting a post-translational inhibition of α-amylase activity in the endosperm during the starch filling period. These findings show unexpected effects of a high level of α-amylase on grain development and composition, notably in carbon partitioning and TAG accumulation, and suggest the presence of a hitherto unknown regulatory pathway during grain filling. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  2. Process for solidifying high-level nuclear waste

    DOEpatents

    Ross, Wayne A.

    1978-01-01

    The addition of a small amount of reducing agent to a mixture of a high-level radioactive waste calcine and glass frit before the mixture is melted will produce a more homogeneous glass which is leach-resistant and suitable for long-term storage of high-level radioactive waste products.

  3. Accumulation of Rutin and Betulinic Acid and Expression of Phenylpropanoid and Triterpenoid Biosynthetic Genes in Mulberry (Morus alba L.).

    PubMed

    Zhao, Shicheng; Park, Chang Ha; Li, Xiaohua; Kim, Yeon Bok; Yang, Jingli; Sung, Gyoo Byung; Park, Nam Il; Kim, Soonok; Park, Sang Un

    2015-09-30

    Mulberry (Morus alba L.) is used in traditional Chinese medicine and is the sole food source of the silkworm. Here, 21 cDNAs encoding phenylpropanoid biosynthetic genes and 21 cDNAs encoding triterpene biosynthetic genes were isolated from mulberry. The expression levels of genes involved in these biosynthetic pathways and the accumulation of rutin, betulin, and betulinic acid, important secondary metabolites, were investigated in different plant organs. Most phenylpropanoid and triterpene biosynthetic genes were highly expressed in leaves and/or fruit, and most genes were downregulated during fruit ripening. The accumulation of rutin was more than fivefold higher in leaves than in other organs, and higher levels of betulin and betulinic acid were found in roots and leaves than in fruit. By comparing the contents of these compounds with gene expression levels, we speculate that MaUGT78D1 and MaLUS play important regulatory roles in the rutin and betulin biosynthetic pathways.

  4. Preservation efficiencies and accumulation rates for biogenic silica and organic C, N, and P in high-latitude sediments: The Ross Sea

    NASA Astrophysics Data System (ADS)

    Demaster, David J.; Ragueneau, Olivier; Nittrouer, Charles A.

    1996-08-01

    . P preservation efficiencies remained relatively high (24-65%) even when the accumulation rates were low (1-2 cm kyr-1) because of the near-zero phosphate fluxes out of the seabed. Of the total P in the seabed (0.04-0.09 wt. %), approximately 25% existed in the form of organic P. The total amount of biogenic silica accumulating on the Ross Sea shelf is ˜2.3 × 1012 g SiO2 yr-1, which is approximately an order of magnitude less than the Ledford-Hoffman et al. [1986] estimate that was based on 210Pb chronologies. Biogenic silica accumulation rates in the southern, central, and western Ross Sea increased during the mid and late Holocene, reaching their maximum values during the past 500 to 1000 years.

  5. Determining Greenland Ice Sheet Accumulation Rates from Radar Remote Sensing

    NASA Technical Reports Server (NTRS)

    Jezek, Kenneth C.

    2001-01-01

    An important component of NASA's Program for Arctic Regional Climate Assessment (PARCA) is a mass balance investigation of the Greenland Ice Sheet. The mass balance is calculated by taking the difference between the snow accumulation and the ice discharge of the ice sheet. Uncertainties in this calculation include the snow accumulation rate, which has traditionally been determined by interpolating data from ice core samples taken throughout the ice sheet. The sparse data associated with ice cores, coupled with the high spatial and temporal resolution provided by remote sensing, have motivated scientists to investigate relationships between accumulation rate and microwave observations.

  6. Bottlenecks in erucic acid accumulation in genetically engineered ultrahigh erucic acid Crambe abyssinica

    PubMed Central

    Guan, Rui; Lager, Ida; Li, Xueyuan; Stymne, Sten; Zhu, Li-Hua

    2014-01-01

    Erucic acid is a valuable industrial fatty acid with many applications. The main producers of this acid are today high erucic rapeseed (Brassica napus) and mustard (Brassica juncea), which have 45%–50% of erucic acid in their seed oils. Crambe abyssinica is an alternative promising producer of this acid as it has 55%–60% of erucic acid in its oil. Through genetic modification (GM) of three genes, we have previously increased the level of erucic acid to 71% (68 mol%) in Crambe seed oil. In this study, we further investigated different aspects of oil biosynthesis in the developing GM Crambe seeds in comparison with wild-type (Wt) Crambe, rapeseed and safflower (Carthamus tinctorius). We show that Crambe seeds have very low phosphatidylcholine-diacylglycerol interconversion, suggesting it to be the main reason why erucic acid is limited in the membrane lipids during oil biosynthesis. We further show that GM Crambe seeds have slower seed development than Wt, accompanied by slower oil accumulation during the first 20 days after flowering (DAF). Despite low accumulation of erucic acid during early stages of GM seed development, nearly 86 mol% of all fatty acids accumulated between 27 and 50 DAF was erucic acid, when 40% of the total oil is laid down. Likely bottlenecks in the accumulation of erucic acid during early stages of GM Crambe seed development are discussed. PMID:24119222

  7. The effect of technogenic emissions on the heavy metals accumulation by herbaceous plants.

    PubMed

    Chaplygin, Victor; Minkina, Tatiana; Mandzhieva, Saglara; Burachevskaya, Marina; Sushkova, Svetlana; Poluektov, Evgeniy; Antonenko, Elena; Kumacheva, Valentina

    2018-02-07

    The effect of technogenic emissions on the input of Pb, Zn, Cd, Cu, Mn, Cr, and Ni into plants from the Poaceae and Asteraceae families has been studied. Soil and plant contamination by anthropogenic emissions from industrial enterprises leads the decreasing of crop quality; therefore, the monitoring investigation of plants and soils acquires special importance. The herbaceous plants may be used as bioindicators for main environmental changes. It was found that the high level of anthropogenic load related to atmospheric emissions from the power plant favors the heavy metal (HM) accumulation in herbaceous plants. Contamination with Pb, Cd, Cr, and Ni was revealed in plants growing near the power plant. Heavy metals arrive to plants from the soil in the form of mobile compounds. Plant family is one of the main factors affecting the HM distribution in the above- and underground parts of plants. Plants from the Poaceae family accumulate less chemical elements in their aboveground parts than the Asteraceae plants. Ambrosia artemisiifolia and Artemisia austriaca are HM accumulators. For assessing the stability of plants under contamination with HMs, metal accumulation by plants from soil (the bioconcentration factor) and metal phytoavailability from plants above- and underground parts (the acropetal coefficient) were calculated. According to the bioconcentration factor and translocation factor values, Poaceae species are most resistant to technogenic contamination with HMs. The translocation factor highest values were found for Tanacetum vulgare; the lowest bioconcentration factor values were typical for Poa pratensis.

  8. Plastic litter accumulation on high-water strandline of urban beaches in Mumbai, India.

    PubMed

    Jayasiri, H B; Purushothaman, C S; Vennila, A

    2013-09-01

    Today, almost every beach on every coastline is threatened by human activities. The inadequate recycling and poor management of waste in developing countries has resulted in considerable quantities of plastic contaminating beaches. Though India has long coastline of 5,420 km along the mainland with 43 % of sandy beaches, data on litter accumulation, particularly the plastics, which are one of the most common and persistent pollutants in marine environment, are scanty. The abundance and distribution of plastic litter was quantitatively assessed in four sandy beaches in Mumbai, India, bimonthly from May 2011 to March 2012. Triplicates of 2 × 2 m (4 m(2)) quadrats were sampled in each beach with a total of 72 quadrats. Overall, average abundance of 11.6 items m(-2) (0.25-282.5 items m(-2)) and 3.24 g m(-2) (0.27-15.53 g m(-2)) plastic litter was recorded in Mumbai beaches. Plastic litter accumulation significantly varied temporally and spatially at p = 0.05. Significantly higher plastic litter accumulation was recorded in Juhu beach. Furthermore, the highest abundance by weight was recorded in November and May numerically. More than 80 % of plastic particles were within the size range of 5-100 mm both by number and weight. Moreover, coloured plastics were predominant with 67 % by number of items and 51 % by weight. Probably, the intense use of beaches for recreation, tourism, and religious activities has increased the potential for plastic contamination in urban beaches in Mumbai.

  9. ION EFFECTS IN THE APS PARTICLE ACCUMULATOR RING

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Calvey, J.; Harkay, K.; Yao, CY.

    2017-06-25

    Trapped ions in the APS Particle Accumulator Ring (PAR) lead to a positive coherent tune shift in both planes, which increases along the PAR cycle as more ions accumulate. This effect has been studied using an ion simulation code developed at SLAC. After modifying the code to include a realistic vacuum profile, multiple ionization, and the effect of shaking the beam to measure the tune, the simulation agrees well with our measurements. This code has also been used to evaluate the possibility of ion instabilities at the high bunch charge needed for the APS-Upgrade.

  10. Association between high-density lipoprotein cholesterol level and pulmonary function in healthy Korean adolescents: the JS high school study.

    PubMed

    Park, Ji Hye; Mun, Seyeon; Choi, Dong Phil; Lee, Joo Young; Kim, Hyeon Chang

    2017-12-11

    Accumulating evidence suggests that high-density lipoprotein (HDL) cholesterol is associated with pulmonary function and pulmonary disorders. The aim of this study was to evaluate the association between HDL cholesterol and pulmonary function in healthy adolescents. This cross-sectional study was based on data collected for the JS High School study. The analysis included 644 adolescents (318 male and 326 female) aged 15-16 years old and free from asthma or chronic obstructive pulmonary disease. Fasting blood samples were collected for hematologic and biochemical assessment. Forced vital capacity volume (FVC) and forced expiratory volume in the 1 s (FEV1) were measured using dry-rolling-seal spirometry. The associations between HDL cholesterol and pulmonary function were analyzed using multiple linear regression models. Among male adolescents, an increase of 1.0 mg/dL in HDL cholesterol was associated with 10 mL decrease in FVC (p = 0.013) and FEV1 (p = 0.013) after adjusting for age, height, weight, alcohol drinking, smoking, physical activity, systolic blood pressure, total cholesterol, triglyceride, and monthly household income. Percent predicted values of FVC (p = 0.036) and FEV1 (p = 0.017) were also inversely associated with HDL cholesterol. However, among female adolescents, HDL cholesterol level was not significantly associated with absolute or percent predictive value of FVC and FEV1. Higher HDL cholesterol level may be associated with decreased pulmonary function among healthy male adolescents. The sex differences observed in the association between HDL cholesterol and pulmonary function need further investigation.

  11. IMPLEMENTATION AND VALIDATION OF A FULLY IMPLICIT ACCUMULATOR MODEL IN RELAP-7

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Haihua; Zou, Ling; Zhang, Hongbin

    2016-01-01

    This paper presents the implementation and validation of an accumulator model in RELAP-7 under the framework of preconditioned Jacobian free Newton Krylov (JFNK) method, based on the similar model used in RELAP5. RELAP-7 is a new nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). RELAP-7 is a fully implicit system code. The JFNK and preconditioning methods used in RELAP-7 is briefly discussed. The slightly modified accumulator model is summarized for completeness. The implemented model was validated with LOFT L3-1 test and benchmarked with RELAP5 results. RELAP-7 and RELAP5 had almost identical results for themore » accumulator gas pressure and water level, although there were some minor difference in other parameters such as accumulator gas temperature and tank wall temperature. One advantage of the JFNK method is its easiness to maintain and modify models due to fully separation of numerical methods from physical models. It would be straightforward to extend the current RELAP-7 accumulator model to simulate the advanced accumulator design.« less

  12. cyclostratigraphy, sequence stratigraphy and organic matter accumulation mechanism

    NASA Astrophysics Data System (ADS)

    Cong, F.; Li, J.

    2016-12-01

    The first member of Maokou Formation of Sichuan basin is composed of well preserved carbonate ramp couplets of limestone and marlstone/shale. It acts as one of the potential shale gas source rock, and is suitable for time-series analysis. We conducted time-series analysis to identify high-frequency sequences, reconstruct high-resolution sedimentation rate, estimate detailed primary productivity for the first time in the study intervals and discuss organic matter accumulation mechanism of source rock under sequence stratigraphic framework.Using the theory of cyclostratigraphy and sequence stratigraphy, the high-frequency sequences of one outcrop profile and one drilling well are identified. Two third-order sequences and eight fourth-order sequences are distinguished on outcrop profile based on the cycle stacking patterns. For drilling well, sequence boundary and four system tracts is distinguished by "integrated prediction error filter analysis" (INPEFA) of Gamma-ray logging data, and eight fourth-order sequences is identified by 405ka long eccentricity curve in depth domain which is quantified and filtered by integrated analysis of MTM spectral analysis, evolutive harmonic analysis (EHA), evolutive average spectral misfit (eASM) and band-pass filtering. It suggests that high-frequency sequences correlate well with Milankovitch orbital signals recorded in sediments, and it is applicable to use cyclostratigraphy theory in dividing high-frequency(4-6 orders) sequence stratigraphy.High-resolution sedimentation rate is reconstructed through the study interval by tracking the highly statistically significant short eccentricity component (123ka) revealed by EHA. Based on sedimentation rate, measured TOC and density data, the burial flux, delivery flux and primary productivity of organic carbon was estimated. By integrating redox proxies, we can discuss the controls on organic matter accumulation by primary production and preservation under the high-resolution sequence

  13. Copper and cobalt accumulation in plants: a critical assessment of the current state of knowledge.

    PubMed

    Lange, Bastien; van der Ent, Antony; Baker, Alan John Martin; Echevarria, Guillaume; Mahy, Grégory; Malaisse, François; Meerts, Pierre; Pourret, Olivier; Verbruggen, Nathalie; Faucon, Michel-Pierre

    2017-01-01

    This review synthesizes contemporary understanding of copper-cobalt (Cu-Co) tolerance and accumulation in plants. Accumulation of foliar Cu and Co to > 300 μg g -1 is exceptionally rare globally, and known principally from the Copperbelt of Central Africa. Cobalt accumulation is also observed in a limited number of nickel (Ni) hyperaccumulator plants occurring on ultramafic soils around the world. None of the putative Cu or Co hyperaccumulator plants appears to comply with the fundamental principle of hyperaccumulation, as foliar Cu-Co accumulation is strongly dose-dependent. Abnormally high plant tissue Cu concentrations occur only when plants are exposed to high soil Cu with a low root to shoot translocation factor. Most Cu-tolerant plants are Excluders sensu Baker and therefore setting nominal threshold values for Cu hyperaccumulation is not informative. Abnormal accumulation of Co occurs under similar circumstances in the Copperbelt of Central Africa as well as sporadically in Ni hyperaccumulator plants on ultramafic soils; however, Co-tolerant plants behave physiologically as Indicators sensu Baker. Practical application of Cu-Co accumulator plants in phytomining is limited due to their dose-dependent accumulation characteristics, although for Co field trials may be warranted on highly Co-contaminated mineral wastes because of its relatively high metal value. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  14. Halloysite nanotubes-induced Al accumulation and oxidative damage in liver of mice after 30-day repeated oral administration.

    PubMed

    Wang, Xue; Gong, Jiachun; Gui, Zongxiang; Hu, Tingting; Xu, Xiaolong

    2018-06-01

    Halloysite (Al 2 Si 2 O 5 (OH) 4 ·nH 2 O) nanotubes (HNTs) are natural clay materials and widely applied in many fields due to their natural hollow tubular structures. Many in vitro studies indicate that HNTs exhibit a high level of biocompatibility, however the in vivo toxicity of HNTs remains unclear. The objective of this study was to assess the hepatic toxicity of the purified HNTs in mice via oral route. The purified HNTs were orally administered to mice at 5, 50, and 300 mg/kg body weight (BW) every day for 30 days. Oral administration of HNTs stimulated the growth of the mice at the low dose (5 mg/kg BW) with no liver toxicity, but inhibited the growth of the mice at the middle (50 mg/kg BW) and high (300 mg/kg BW) doses. In addition, oral administration of HNTs at the high dose caused Al accumulation in the liver but had no marked effect on the Si content in the organ. The Al accumulation caused significant oxidative stress in the liver, which induced hepatic dysfunction and histopathologic changes. These findings demonstrated that Al accumulation-induced oxidative stress played an important role in the oral HNTs-caused liver injury. © 2018 Wiley Periodicals, Inc.

  15. Accumulation of organic C components in soil and aggregates

    PubMed Central

    Yu, Hongyan; Ding, Weixin; Chen, Zengming; Zhang, Huanjun; Luo, Jiafa; Bolan, Nanthi

    2015-01-01

    To explore soil organic carbon (SOC) accumulation mechanisms, the dynamics of C functional groups and macroaggregation were studied synchronously through aggregate fractionation and 13C NMR spectroscopy in sandy loam soil following an 18-year application of compost and fertilizer in China. Compared with no fertilizer control, both compost and fertilizer improved SOC content, while the application of compost increased macroaggregation. Fertilizer application mainly increased the levels of recalcitrant organic C components characterized by methoxyl/N-alkyl C and alkyl C, whereas compost application mainly promoted the accumulation of methoxyl/N-alkyl C, phenolic C, carboxyl C, O-alkyl C and di-O-alkyl C in bulk soil. The preferential accumulation of organic C functional groups in aggregates depended on aggregate size rather than nutrient amendments. These groups were characterized by phenolic C and di-O-alkyl C in the silt + clay fraction, carboxyl C in microaggregates and phenolic C, carboxyl C and methoxyl/N-alkyl C in macroaggregates. Thus, the differences in accumulated organic C components in compost- and fertilizer-amended soils were primarily attributable to macroaggregation. The accumulation of methoxyl/N-alkyl C in microaggregates effectively promoted macroaggregation. Our results suggest that organic amendment rich in methoxyl/N-alkyl C effectively improved SOC content and accelerated macroaggregation in the test soil. PMID:26358660

  16. Assessment of Heavy Metals Contamination in Reclaimed Mine Soil and their Accumulation and Distribution in Eucalyptus Hybrid.

    PubMed

    Maiti, Subodh Kumar; Rana, Vivek

    2017-01-01

    The metal contamination in reclaimed mine soil (RMS) of Jharia coal field, Dhanbad (India) using various contamination indices and their accumulation in tissues of Eucalyptus hybrid were assessed. In RMS, metal concentrations were found higher (202%-533%) than control soil (CS) with major contribution of Co and Mn followed by Zn, Cu and Pb. Principal component analysis (PCA) of metals present in RMS was carried out to assess their origin in RMS. The contamination factor (CF) values in RMS indicated moderate to very high level of pollution (ranged between 2.02 and 5.33). Higher accumulation of Pb in barks (three times), Zn in leaves (4.5 times), Mn in leaves (19 times), and Cu in roots (1.4 times) was found in trees growing on RMS than CS. The study concluded that different tree tissues accumulate varied concentration of heavy metals in RMS and thus for biomonitoring of metals, specific tissues has to be selected.

  17. Mercury accumulation plant Cyrtomium macrophyllum and its potential for phytoremediation of mercury polluted sites.

    PubMed

    Xun, Yu; Feng, Liu; Li, Youdan; Dong, Haochen

    2017-12-01

    Cyrtomium macrophyllum naturally grown in 225.73 mg kg -1 of soil mercury in mining area was found to be a potential mercury accumulator plant with the translocation factor of 2.62 and the high mercury concentration of 36.44 mg kg -1 accumulated in its aerial parts. Pot experiments indicated that Cyrtomium macrophyllum could even grow in 500 mg kg -1 of soil mercury with observed inhibition on growth but no obvious toxic effects, and showed excellent mercury accumulation and translocation abilities with both translocation and bioconcentration factors greater than 1 when exposed to 200 mg kg -1 and lower soil mercury, indicating that it could be considered as a great mercury accumulating species. Furthermore, the leaf tissue of Cyrtomium macrophyllum showed high resistance to mercury stress because of both the increased superoxide dismutase activity and the accumulation of glutathione and proline induced by mercury stress, which favorited mercury translocation from the roots to the aerial parts, revealing the possible reason for Cyrtomium macrophyllum to tolerate high concentration of soil mercury. In sum, due to its excellent mercury accumulation and translocation abilities as well as its high resistance to mercury stress, the use of Cyrtomium macrophyllum should be a promising approach to remediating mercury polluted soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. A Framework for Translating a High Level Security Policy into Low Level Security Mechanisms

    NASA Astrophysics Data System (ADS)

    Hassan, Ahmed A.; Bahgat, Waleed M.

    2010-01-01

    Security policies have different components; firewall, active directory, and IDS are some examples of these components. Enforcement of network security policies to low level security mechanisms faces some essential difficulties. Consistency, verification, and maintenance are the major ones of these difficulties. One approach to overcome these difficulties is to automate the process of translation of high level security policy into low level security mechanisms. This paper introduces a framework of an automation process that translates a high level security policy into low level security mechanisms. The framework is described in terms of three phases; in the first phase all network assets are categorized according to their roles in the network security and relations between them are identified to constitute the network security model. This proposed model is based on organization based access control (OrBAC). However, the proposed model extend the OrBAC model to include not only access control policy but also some other administrative security policies like auditing policy. Besides, the proposed model enables matching of each rule of the high level security policy with the corresponding ones of the low level security policy. Through the second phase of the proposed framework, the high level security policy is mapped into the network security model. The second phase could be considered as a translation of the high level security policy into an intermediate model level. Finally, the intermediate model level is translated automatically into low level security mechanism. The paper illustrates the applicability of proposed approach through an application example.

  19. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from the...

  20. The chromium accumulation and its physiological effects in juvenile rockfish, Sebastes schlegelii, exposed to different levels of dietary chromium (Cr(6+)) concentrations.

    PubMed

    Kim, Jun-Hwan; Kang, Ju-Chan

    2016-01-01

    Juvenile rockfish (mean length 13.7±1.7 cm, and mean weight 55.6±4.8 g) were exposed for 4 weeks with the different levels of dietary chromium (Cr(6+)) at 0, 30, 60, 120 and 240 mg/kg. The profile of chromium in the tissues of rockfish is dependent on the exposure periods and chromium concentration. After 4 weeks, the order of chromium accumulation in tissues was liver>kidney>spleen>intestine>gill>muscle. The dietary chromium exposure decreased the growth rate and hepatosomatic index of rockfish. The major hematological findings were significant decrease in the red blood cell (RBC) count, hematocrit (Ht) value, and hemoglobin (Hb) concentration exposed to ≥120 mg/kg chromium concentrations. The dietary chromium exposure (≥120 mg/kg) led to notable increase in glucose, cholesterol, glutamic oxalate transaminase (GOT), and glutamic pyruvate transaminase (GPT) in plasma, whereas there was no considerable change in calcium, magnesium, total protein, and alkaline phosphatase (ALP). The results indicated that the dietary chromium exposure to rockfish can induce significant chromium accumulation in the specific tissues, inhibition of growth, and hematological alterations. Copyright © 2015 Elsevier B.V. All rights reserved.