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Sample records for nitrogen deficiency increases

  1. Iron deficiency increases growth and nitrogen-fixation rates of phosphorus-deficient marine cyanobacteria.

    Science.gov (United States)

    Garcia, Nathan S; Fu, Feixue; Sedwick, Peter N; Hutchins, David A

    2015-01-01

    Marine dinitrogen (N2)-fixing cyanobacteria have large impacts on global biogeochemistry as they fix carbon dioxide (CO2) and fertilize oligotrophic ocean waters with new nitrogen. Iron (Fe) and phosphorus (P) are the two most important limiting nutrients for marine biological N2 fixation, and their availabilities vary between major ocean basins and regions. A long-standing question concerns the ability of two globally dominant N2-fixing cyanobacteria, unicellular Crocosphaera and filamentous Trichodesmium, to maintain relatively high N2-fixation rates in these regimes where both Fe and P are typically scarce. We show that under P-deficient conditions, cultures of these two cyanobacteria are able to grow and fix N2 faster when Fe deficient than when Fe replete. In addition, growth affinities relative to P increase while minimum concentrations of P that support growth decrease at low Fe concentrations. In Crocosphaera, this effect is accompanied by a reduction in cell sizes and elemental quotas. Relatively high growth rates of these two biogeochemically critical cyanobacteria in low-P, low-Fe environments such as those that characterize much of the oligotrophic ocean challenge the common assumption that low Fe levels can have only negative effects on marine primary producers. The closely interdependent influence of Fe and P on N2-fixing cyanobacteria suggests that even subtle shifts in their supply ratio in the past, present and future oceans could have large consequences for global carbon and nitrogen cycles.

  2. Increased Sucrose in the Hypocotyls of Radish Sprouts Contributes to Nitrogen Deficiency-Induced Anthocyanin Accumulation

    Science.gov (United States)

    Su, Nana; Wu, Qi; Cui, Jin

    2016-01-01

    Effects of nitrogen (N) deficiency and sucrose (Suc) addition on regulation of anthocyanin biosynthesis and their relationship were investigated in this study. Radish sprouts subjected to N deficiency had 50% higher anthocyanin accumulation than when grown in Hoagland solution (a nutrient medium with all macronutrients). The contents of endogenous soluble sugars (Suc, fructose, and glucose) in the hypocotyls were also markedly increased by N limitation, with Suc showing the highest increase. Inhibition of carbohydrate biosynthesis by addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) also eliminated N deficiency-induced anthocyanin accumulation. The latter was further supported by the expression of anthocyanin biosynthesis related genes and decreased activities of nitrate reductase in the presence of Suc. Together our results indicate that N deficiency-induced anthocyanin accumulation was, at least partly, dependent on the increase of the soluble sugar, especially Suc. This work is the first comprehensive study on relationship between N deficiency and sugar content on anthocyanin accumulation in the hypocotyls of radish sprouts. PMID:28083009

  3. Acclimation of photosynthesis to nitrogen deficiency in Phaseolus vulgaris.

    Science.gov (United States)

    Antal, Taras; Mattila, Heta; Hakala-Yatkin, Marja; Tyystjärvi, Taina; Tyystjärvi, Esa

    2010-09-01

    Nitrogen deficiency diminishes consumption of photosynthates in anabolic metabolism. We studied adjustments of the photosynthetic machinery in nitrogen-deficient bean plants and found four phenomena. First, the number of chloroplasts per cell decreased. Chloroplasts of nitrogen starved leaves contained less pigments than those of control leaves, but the in vitro activities of light reactions did not change when measured on chlorophyll basis. Second, nitrogen deficiency induced cyclic electron transfer. The amounts of Rubisco and ferredoxin-NADP(+) reductase decreased in nitrogen starved plants. Low activities of these enzymes are expected to lead to increase in reduction of oxygen by photosystem I. However, diaminobenzidine staining did not reveal hydrogen peroxide production in nitrogen starved plants. Measurements of far-red-light-induced redox changes of the primary donor of photosystem I suggested that instead of producing oxygen radicals, nitrogen starved plants develop a high activity of cyclic electron transport that competes with oxygen for electrons. Nitrogen starvation led to decrease in photochemical quenching and increase in non-photochemical quenching, indicating that cyclic electron transport reduces the plastoquinone pool and acidifies the lumen. A third effect is redistribution of excitation energy between the photosystems in favor of photosystem I. Thus, thylakoids of nitrogen starved plants appeared to be locked in state 2, which further protects photosystem II by decreasing its absorption cross-section. As a fourth response, the proportion of non-Q(B)-reducing photosystem II reaction centers increased and the redox potential of the Q(B)/Q(B)(-) pair decreased by 25 mV in a fraction of photosystem II centers of nitrogen starved plants.

  4. Phenylbutyrate improves nitrogen disposal via alternative pathway without eliciting an increase in protein breakdown and catabolism in control and ornithine transcarbamylace-deficient patients

    Science.gov (United States)

    Phenylbutyrate (PB) is a drug used in urea cycle disorder patients to elicit alternative pathways for nitrogen disposal. However, PB decreases plasma branched chain amino acid (BCAA) concentrations and prior research suggests that PB may increase leucine oxidation, indicating increased protein degra...

  5. Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency

    National Research Council Canada - National Science Library

    Chu, Fei-Fei; Shen, Xiao-Fei; Lam, Paul K S; Zeng, Raymond J

    2015-01-01

    Polyphosphate (Poly-P) accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity...

  6. Engineering Pseudomonas protegens Pf-5 for Nitrogen Fixation and its Application to Improve Plant Growth under Nitrogen-Deficient Conditions

    Science.gov (United States)

    Setten, Lorena; Soto, Gabriela; Mozzicafreddo, Matteo; Fox, Ana Romina; Lisi, Christian; Cuccioloni, Massimiliano; Angeletti, Mauro; Pagano, Elba; Díaz-Paleo, Antonio; Ayub, Nicolás Daniel

    2013-01-01

    Nitrogen is the second most critical factor for crop production after water. In this study, the beneficial rhizobacterium Pseudomonas protegens Pf-5 was genetically modified to fix nitrogen using the genes encoding the nitrogenase of Pseudomonas stutzeri A1501 via the X940 cosmid. Pf-5 X940 was able to grow in L medium without nitrogen, displayed high nitrogenase activity and released significant quantities of ammonium to the medium. Pf-5 X940 also showed constitutive expression and enzymatic activity of nitrogenase in ammonium medium or in nitrogen-free medium, suggesting a constitutive nitrogen fixation. Similar to Pseudomonas protegens Pf-5, Pseudomonas putida, Pseudomonas veronii and Pseudomonas taetrolens but not Pseudomonas balearica and Pseudomonas stutzeri transformed with cosmid X940 showed constitutive nitrogenase activity and high ammonium production, suggesting that this phenotype depends on the genome context and that this technology to obtain nitrogen-fixing bacteria is not restricted to Pf-5. Interestingly, inoculation of Arabidopsis, alfalfa, tall fescue and maize with Pf-5 X940 increased the ammonium concentration in soil and plant productivity under nitrogen-deficient conditions. In conclusion, these results open the way to the production of effective recombinant inoculants for nitrogen fixation on a wide range of crops. PMID:23675499

  7. Engineering Pseudomonas protegens Pf-5 for nitrogen fixation and its application to improve plant growth under nitrogen-deficient conditions.

    Science.gov (United States)

    Setten, Lorena; Soto, Gabriela; Mozzicafreddo, Matteo; Fox, Ana Romina; Lisi, Christian; Cuccioloni, Massimiliano; Angeletti, Mauro; Pagano, Elba; Díaz-Paleo, Antonio; Ayub, Nicolás Daniel

    2013-01-01

    Nitrogen is the second most critical factor for crop production after water. In this study, the beneficial rhizobacterium Pseudomonas protegens Pf-5 was genetically modified to fix nitrogen using the genes encoding the nitrogenase of Pseudomonas stutzeri A1501 via the X940 cosmid. Pf-5 X940 was able to grow in L medium without nitrogen, displayed high nitrogenase activity and released significant quantities of ammonium to the medium. Pf-5 X940 also showed constitutive expression and enzymatic activity of nitrogenase in ammonium medium or in nitrogen-free medium, suggesting a constitutive nitrogen fixation. Similar to Pseudomonas protegens Pf-5, Pseudomonas putida, Pseudomonas veronii and Pseudomonas taetrolens but not Pseudomonas balearica and Pseudomonas stutzeri transformed with cosmid X940 showed constitutive nitrogenase activity and high ammonium production, suggesting that this phenotype depends on the genome context and that this technology to obtain nitrogen-fixing bacteria is not restricted to Pf-5. Interestingly, inoculation of Arabidopsis, alfalfa, tall fescue and maize with Pf-5 X940 increased the ammonium concentration in soil and plant productivity under nitrogen-deficient conditions. In conclusion, these results open the way to the production of effective recombinant inoculants for nitrogen fixation on a wide range of crops.

  8. Engineering Pseudomonas protegens Pf-5 for nitrogen fixation and its application to improve plant growth under nitrogen-deficient conditions.

    Directory of Open Access Journals (Sweden)

    Lorena Setten

    Full Text Available Nitrogen is the second most critical factor for crop production after water. In this study, the beneficial rhizobacterium Pseudomonas protegens Pf-5 was genetically modified to fix nitrogen using the genes encoding the nitrogenase of Pseudomonas stutzeri A1501 via the X940 cosmid. Pf-5 X940 was able to grow in L medium without nitrogen, displayed high nitrogenase activity and released significant quantities of ammonium to the medium. Pf-5 X940 also showed constitutive expression and enzymatic activity of nitrogenase in ammonium medium or in nitrogen-free medium, suggesting a constitutive nitrogen fixation. Similar to Pseudomonas protegens Pf-5, Pseudomonas putida, Pseudomonas veronii and Pseudomonas taetrolens but not Pseudomonas balearica and Pseudomonas stutzeri transformed with cosmid X940 showed constitutive nitrogenase activity and high ammonium production, suggesting that this phenotype depends on the genome context and that this technology to obtain nitrogen-fixing bacteria is not restricted to Pf-5. Interestingly, inoculation of Arabidopsis, alfalfa, tall fescue and maize with Pf-5 X940 increased the ammonium concentration in soil and plant productivity under nitrogen-deficient conditions. In conclusion, these results open the way to the production of effective recombinant inoculants for nitrogen fixation on a wide range of crops.

  9. Influence of nitrogen deficiency on photosynthesis and chloroplast ultrastructure of pepper plants (Research Note

    Directory of Open Access Journals (Sweden)

    S. DONCHEVA

    2008-12-01

    Full Text Available Pepper plants (Capsicum annuum L. cv. Zlaten Medal were grown on nutrient solution without nitrogen, and photosynthetic response of plants was examined by determination of leaf CO2 fixation and chlorophyll and carotenoid contents. The absence of nitrogen in the medium resulted in a decrease of the leaf area and of plant biomass accumulation, and in an increase of the root-shoot dry weight ratio. The photosynthetic activity and chlorophyll and carotenoid contents decreased significantly under nitrogen deprivation. Examination of nitrogen deficient leaves by transmission electron microscopy showed dramatic changes in chloroplast ultrastructure. The proportion of starch granules and plastoglobules in the stroma matrix was increased and internal membrane system was greatly reduced. It seems that nitrogen plays an important role in the formation of chloroplast structure and hence to the photosynthetic intensity and productivity of pepper plants.

  10. Iron deficiency affects nitrogen metabolism in cucumber (Cucumis sativus L. plants

    Directory of Open Access Journals (Sweden)

    Borlotti Andrea

    2012-10-01

    Full Text Available Abstract Background Nitrogen is a principal limiting nutrient in plant growth and development. Among factors that may limit NO3- assimilation, Fe potentially plays a crucial role being a metal cofactor of enzymes of the reductive assimilatory pathway. Very few information is available about the changes of nitrogen metabolism occurring under Fe deficiency in Strategy I plants. The aim of this work was to study how cucumber (Cucumis sativus L. plants modify their nitrogen metabolism when grown under iron deficiency. Results The activity of enzymes involved in the reductive assimilation of nitrate and the reactions that produce the substrates for the ammonium assimilation both at root and at leaf levels in Fe-deficient cucumber plants were investigated. Under Fe deficiency, only nitrate reductase (EC 1.7.1.1 activity decreased both at the root and leaf level, whilst for glutamine synthetase (EC 6.3.1.2 and glutamate synthase (EC 1.4.1.14 an increase was found. Accordingly, the transcript analysis for these enzymes showed the same behaviour except for root nitrate reductase which increased. Furthermore, it was found that amino acid concentration greatly decreased in Fe-deficient roots, whilst it increased in the corresponding leaves. Moreover, amino acids increased in the xylem sap of Fe-deficient plants. Conclusions The data obtained in this work provided new insights on the responses of plants to Fe deficiency, suggesting that this nutritional disorder differentially affected N metabolism in root and in leaf. Indeed under Fe deficiency, roots respond more efficiently, sustaining the whole plant by furnishing metabolites (i.e. aa, organic acids to the leaves.

  11. Iron deficiency affects nitrogen metabolism in cucumber (Cucumis sativus L.) plants.

    Science.gov (United States)

    Borlotti, Andrea; Vigani, Gianpiero; Zocchi, Graziano

    2012-10-11

    Nitrogen is a principal limiting nutrient in plant growth and development. Among factors that may limit NO3- assimilation, Fe potentially plays a crucial role being a metal cofactor of enzymes of the reductive assimilatory pathway. Very few information is available about the changes of nitrogen metabolism occurring under Fe deficiency in Strategy I plants. The aim of this work was to study how cucumber (Cucumis sativus L.) plants modify their nitrogen metabolism when grown under iron deficiency. The activity of enzymes involved in the reductive assimilation of nitrate and the reactions that produce the substrates for the ammonium assimilation both at root and at leaf levels in Fe-deficient cucumber plants were investigated. Under Fe deficiency, only nitrate reductase (EC 1.7.1.1) activity decreased both at the root and leaf level, whilst for glutamine synthetase (EC 6.3.1.2) and glutamate synthase (EC 1.4.1.14) an increase was found. Accordingly, the transcript analysis for these enzymes showed the same behaviour except for root nitrate reductase which increased. Furthermore, it was found that amino acid concentration greatly decreased in Fe-deficient roots, whilst it increased in the corresponding leaves. Moreover, amino acids increased in the xylem sap of Fe-deficient plants. The data obtained in this work provided new insights on the responses of plants to Fe deficiency, suggesting that this nutritional disorder differentially affected N metabolism in root and in leaf. Indeed under Fe deficiency, roots respond more efficiently, sustaining the whole plant by furnishing metabolites (i.e. aa, organic acids) to the leaves.

  12. Identification and quantification of nitrogen nutrient deficiency in the activated sludge process using respirometry

    NARCIS (Netherlands)

    Ning, Z.; Patry, G.G.; Spanjers, H.

    2000-01-01

    Experimental protocols to identify and quantify nitrogen nutrient deficiency in the activated sludge process were developed and tested using respirometry. Respirometric experiments showed that when a nitrogen nutrient deficient sludge is exposed to ammonia nitrogen, the oxygen uptake rate (OUR) of t

  13. Identification and quantification of nitrogen nutrient deficiency in the activated sludge process using respirometry

    NARCIS (Netherlands)

    Ning, Z.; Patry, G.G.; Spanjers, H.

    2000-01-01

    Experimental protocols to identify and quantify nitrogen nutrient deficiency in the activated sludge process were developed and tested using respirometry. Respirometric experiments showed that when a nitrogen nutrient deficient sludge is exposed to ammonia nitrogen, the oxygen uptake rate (OUR) of

  14. Mitigating ammonia nitrogen deficiency in dairy wastewaters for algae cultivation.

    Science.gov (United States)

    Lu, Qian; Zhou, Wenguang; Min, Min; Ma, Xiaochen; Ma, Yiwei; Chen, Paul; Zheng, Hongli; Doan, Yen T T; Liu, Hui; Chen, Chi; Urriola, Pedro E; Shurson, Gerald C; Ruan, Roger

    2016-02-01

    This study demonstrated that the limiting factor to algae growth on dairy wastewater was the ammonia nitrogen deficiency. Dairy wastewaters were mixed with a slaughterhouse wastewater that has much higher ammonia nitrogen content. The results showed the mixing wastewaters improved the nutrient profiles and biomass yield at low cost. Algae grown on mixed wastewaters contained high protein (55.98-66.91%) and oil content (19.10-20.81%) and can be exploited to produce animal feed and biofuel. Furthermore, algae grown on mixed wastewater significantly reduced nutrient contents remained in the wastewater after treatment. By mitigating limiting factor to algae growth on dairy wastewaters, the key issue of low biomass yield of algae grown on dairy wastewaters was resolved and the wastewater nutrient removal efficiency was significantly improved by this study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Nitrogen deficiency in barley (Hordeum vulgare) seedlings induces molecular and metabolic adjustments that trigger aphid resistance.

    Science.gov (United States)

    Comadira, Gloria; Rasool, Brwa; Karpinska, Barbara; Morris, Jenny; Verrall, Susan R; Hedley, Peter E; Foyer, Christine H; Hancock, Robert D

    2015-06-01

    Agricultural nitrous oxide (N2O) pollution resulting from the use of synthetic fertilizers represents a significant contribution to anthropogenic greenhouse gas emissions, providing a rationale for reduced use of nitrogen (N) fertilizers. Nitrogen limitation results in extensive systems rebalancing that remodels metabolism and defence processes. To analyse the regulation underpinning these responses, barley (Horedeum vulgare) seedlings were grown for 7 d under N-deficient conditions until net photosynthesis was 50% lower than in N-replete controls. Although shoot growth was decreased there was no evidence for the induction of oxidative stress despite lower total concentrations of N-containing antioxidants. Nitrogen-deficient barley leaves were rich in amino acids, sugars and tricarboxylic acid cycle intermediates. In contrast to N-replete leaves one-day-old nymphs of the green peach aphid (Myzus persicae) failed to reach adulthood when transferred to N-deficient barley leaves. Transcripts encoding cell, sugar and nutrient signalling, protein degradation and secondary metabolism were over-represented in N-deficient leaves while those associated with hormone metabolism were similar under both nutrient regimes with the exception of mRNAs encoding proteins involved in auxin metabolism and responses. Significant similarities were observed between the N-limited barley leaf transcriptome and that of aphid-infested Arabidopsis leaves. These findings not only highlight significant similarities between biotic and abiotic stress signalling cascades but also identify potential targets for increasing aphid resistance with implications for the development of sustainable agriculture.

  16. Potassium deficiency affects the carbon-nitrogen balance in cotton leaves.

    Science.gov (United States)

    Hu, Wei; Coomer, Taylor D; Loka, Dimitra A; Oosterhuis, Derrick M; Zhou, Zhiguo

    2017-06-01

    Potassium (K) plays important roles in the metabolism of carbon (C) and nitrogen (N), but studies of K deficiency affecting C-N balance are lacking. This study explored the influence of K deficiency on C-N interaction in cotton leaves by conducting a field experiment with cotton cultivar DP0912 under two K rates (K0: 0 kg K2O ha(-1) and K67: 67 kg K2O ha(-1)) and a controlled environment experiment with K-deficient solution (K1: 0 mM K(+)) and K-sufficient solution (K2: 6 mM K(+)). The results showed that leaf K content, leaf number, leaf area, boll number, reproductive dry weight and total dry weight were significant lower under K deficiency (K0 or K1). Lower total chlorophyll content and Chl a/b ratio, and decreased Pn along with lower Gs and higher Ci were measured under K deficiency, suggesting that the decrease in Pn was resulted from non-stomatal limitation. Leaf glucose, fructose, sucrose and starch contents were higher under K deficiency, because lower sucrose export was detected in phloem. Although leaf nitrate and ammonium contents significantly decreased, free amino acid content was increased by 40-63% under K deficiency, since lower amino acid export was also measured in phloem. K deficiency also induced lower soluble protein content in leaves. Leaf ATP level was significantly increased under K deficiency, indicating ATP utilization was lower, so that less energy was supplied to C and N metabolism. The ratio of soluble sugar to free amino acid and the C/N ratio markedly increased under K deficiency, and one reason was that the phloem export reduced more prominent for sucrose (54.6-78.0%) than amino acid (36.7-85.4%) under K deficiency. In addition, lower phosphoenolpyruvate carboxylase activity limited malate and citrate biosynthesis under K deficiency, causing a decrease of C flux into the amino acids, which was not beneficial for maintaining C-N balance. Sucrose phosphate synthase and nitrate reductase activities were lower under K deficiency

  17. Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency.

    Science.gov (United States)

    Chu, Fei-Fei; Shen, Xiao-Fei; Lam, Paul K S; Zeng, Raymond J

    2015-09-28

    Polyphosphate (Poly-P) accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity. In this article, the utilization of polyphosphates and the regreening process under N resupplying conditions, especially for lipid production reviving, were investigated. This regreening process was completed within approximately 3-5 days. Polyphosphates were first degraded within 3 days in the regreening process, with and without an external P supply, and the degradation preceded the assimilation of phosphate in the media with an external P offering. Nitrate assimilation was markedly influenced by the starvation of P after polyphosphates were exhausted in the medium without external phosphates, and then the reviving process of biomass and lipid production was strictly impeded. It is, thus, reasonable to assume that simultaneous provision of external N and P is essential for overall biodiesel production revival during the regreening process.

  18. Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency

    Directory of Open Access Journals (Sweden)

    Fei-Fei Chu

    2015-09-01

    Full Text Available Polyphosphate (Poly-P accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity. In this article, the utilization of polyphosphates and the regreening process under N resupplying conditions, especially for lipid production reviving, were investigated. This regreening process was completed within approximately 3–5 days. Polyphosphates were first degraded within 3 days in the regreening process, with and without an external P supply, and the degradation preceded the assimilation of phosphate in the media with an external P offering. Nitrate assimilation was markedly influenced by the starvation of P after polyphosphates were exhausted in the medium without external phosphates, and then the reviving process of biomass and lipid production was strictly impeded. It is, thus, reasonable to assume that simultaneous provision of external N and P is essential for overall biodiesel production revival during the regreening process.

  19. Cytokinin-dependent improvement in transgenic P(SARK)::IPT tobacco under nitrogen deficiency.

    Science.gov (United States)

    Rubio-Wilhelmi, María Del Mar; Sanchez-Rodriguez, Eva; Rosales, Miguel Angel; Blasco, Begoña; Rios, Juan Jose; Romero, Luis; Blumwald, Eduardo; Ruiz, Juan Manuel

    2011-10-12

    Wild-type (WT) and transgenic tobacco plants overexpressing isopentenyltransferase (IPT), a gene coding the rate-limiting step in cytokinin (CKs) synthesis, were grown under limited nitrogen (N) conditions to evaluate the role of CKs in NUE (N-use efficiency) and in different parameters that determine the quality of tobacco leaves. The results indicate that WT tobacco plants submitted to N deficiency show a decline in the leaf/root ratio, associated with a decrease in the NUE and in tobacco-leaf quality, defined by an increase in the quantity of nicotine. On the contrary, the transgenic plants submitted to N deficiency maintained the leaf/root ratio, presenting a higher NUE and greater quality of tobacco leaves than the WT plants, as the latter showed reduced nicotine and an increase in reducing sugars under severe N-deficiency conditions. Therefore, the overexpression of CKs under N deficiency could be a useful tool to improve tobacco cultivation, given that it could reduce N-fertilizer application and thereby provide economic savings and environmental benefits, maintaining yield and improving tobacco leaf quality.

  20. Latent manganese deficiency increases transpiration in barley (Hordeum vulgare)

    DEFF Research Database (Denmark)

    Hebbern, Christopher Alan; Laursen, Kristian Holst; Ladegaard, Anne Hald

    2009-01-01

    To investigate if latent manganese (Mn) deficiency leads to increased transpiration, barley plants were grown for 10 weeks in hydroponics with daily additions of Mn in the low nM range. The Mn-starved plants did not exhibit visual leaf symptoms of Mn deficiency, but Chl a fluorescence measurements...

  1. Effect of Increasing Nitrogen Deposition on Soil Microbial Communities

    OpenAIRE

    2011-01-01

    Increasing nitrogen deposition, increasing atmospheric CO2, and decreasing biodiversity are three main environmental changes occurring on a global scale. The BioCON (Biodiversity, CO2, and Nitrogen) ecological experiment site at the University of Minnesota's Cedar Creek Ecosystem Science Reserve started in 1997, to better understand how these changes would affect soil systems. To understand how increasing nitrogen deposition affects the microbial community diversity, heterogeneity, and functi...

  2. Biomarkers for detecting nitrogen deficiency during alcoholic fermentation in different commercial wine yeast strains.

    Science.gov (United States)

    Gutiérrez, Alicia; Chiva, Rosana; Beltran, Gemma; Mas, Albert; Guillamon, José Manuel

    2013-05-01

    Nitrogen deficiencies in grape musts are one of the main causes of stuck or sluggish wine fermentations. Several putative biomarkers were tested in order to analyze their appropriateness to detect nitrogen stress in the yeast. To this aim, four commercial wine strains (PDM, ARM, RVA and TTA) were grown in a synthetic grape must with different nitrogen concentrations. Trehalose accumulation, arginase activity and the expression of eleven genes were tested in these wine strains, known to have different nitrogen requirements. The overall response of the four strains was similar, with differences in response intensity (PDM and RVA with higher intensity) and response time (which was also related with nitrogen consumption time). Trehalose response was mostly related to entry into the stationary phase, whereas arginase activity was responsive to nitrogen depletion, although its measurement is too complicated to be used for routine monitoring during winemaking. The expression of the genes DAL4, DAL5, DUR3 and GAP1 was clearly related to nitrogen depletion and thus, GAP1 and DAL4 were selected as markers of nitrogen deficiency. In order to adapt expression analysis to winemaking conditions, the original strains were transformed into reporter strains based on the expression of green fluorescent protein (GFP) under control of the promoters for GAP1 and DAL4. The transformants had a similar fermentative capacity to the parental strains and were able to detect alterations in yeast physiological status due to nitrogen limitations.

  3. Phosphorus plays an important role in enhancing biodiesel productivity of Chlorella vulgaris under nitrogen deficiency.

    Science.gov (United States)

    Chu, Fei-Fei; Chu, Pei-Na; Cai, Pei-Jie; Li, Wen-Wei; Lam, Paul K S; Zeng, Raymond J

    2013-04-01

    To investigate the role of phosphorus in lipid production under nitrogen starvation conditions, five types of media possessing different nitrogen and phosphorus concentrations or their combination were prepared to culture Chlorella vulgaris. It was found that biomass production under nitrogen deficient condition with sufficient phosphorus supply was similar to that of the control (with sufficient nutrition), resulting in a maximum lipid productivity of 58.39 mg/L/day. Meanwhile, 31P NMR showed that phosphorus in the medium was transformed and accumulated as polyphosphate in cells. The uptake rate of phosphorus in cells was 3.8 times higher than the uptake rate of the control. This study demonstrates that phosphorus plays an important role in lipid production of C. vulgaris under nitrogen deficient conditions and implies a potential to combine phosphorus removal from wastewater with biodiesel production via microalgae.

  4. Fertilizer-Induced Advances in Corn Growth Stage and Quantitative Definitions of Nitrogen Deficiencies

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Evidence that nitrogen(N)fertilization tends to accelerate maturation as well as increase rates of growth has received little attention when diagnosing N deficiencies in corn(Zea mays L.).Such a tendency could be a potential source of errors when the diagnosis is solely based on comparing plants with different rates of growth.Whether N fertilization could accelerate rates of growth and maturation was tested in a field study with 12 paired plots representing relatively large variability in soil properties and landscape positions.The plots were located under conditions where preplant N fertilization reduced or avoided temporary N shortages for some plants but did not reduce for other plants early in the season.We measured corn heights to the youngest leaf collar,stages of growth and chlorophyll meter readings(CMRs).The added N advanced growth stages as well as increased corn heights and CMRs at any given time.Fertilization effects on corn heights,growth stages and ear weights were statistically significant(P<0.05)despite substantial variability associated with landscape.Reductions in growth due to a temporary shortage of N within a growth stage might be partially offset by longer periods of growth within that stage to physiological maturity.Temporary shortages of N,therefore,may produce symptoms of N deficiency in situations where subsequent additions of N should not be expected to increase yields.Recognition of these two somewhat different effects(i.e.,increase growth rates and advance growth stages)on corn growth could help to define N deficiency more precisely and to improve the accuracy of diagnosing N status in production agriculture.

  5. Effect of Increasing Nitrogen Deposition on Soil Microbial Communities

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Shengmu; Xue, Kai; He, Zhili; VanNostrand, Joy D.; Liu, Jianshe; Hobbie, Sarah E.; Reich, Peter B.; Zhou, Jizhong

    2010-05-17

    Increasing nitrogen deposition, increasing atmospheric CO2, and decreasing biodiversity are three main environmental changes occurring on a global scale. The BioCON (Biodiversity, CO2, and Nitrogen) ecological experiment site at the University of Minnesota's Cedar Creek Ecosystem Science Reserve started in 1997, to better understand how these changes would affect soil systems. To understand how increasing nitrogen deposition affects the microbial community diversity, heterogeneity, and functional structure impact soil microbial communities, 12 samples were collected from the BioCON plots in which nitrogenous fertilizer was added to simulate the effect of increasing nitrogen deposition and 12 samples from without added fertilizer. DNA from the 24 samples was extracted using a freeze-grind protocol, amplified, labeled with a fluorescent dye, and then hybridized to GeoChip, a functional gene array containing probes for genes involved in N, S and C cycling, metal resistance and organic contaminant degradation. Detrended correspondence analysis (DCA) of all genes detected was performed to analyze microbial community patterns. The first two axes accounted for 23.5percent of the total variation. The samples fell into two major groups: fertilized and non-fertilized, suggesting that nitrogenous fertilizer had a significant impact on soil microbial community structure and diversity. The functional gene numbers detected in fertilized samples was less that detected in non-fertilizer samples. Functional genes involving in the N cycling were mainly discussed.

  6. A Comparative Study of Ethylene Emanation upon Nitrogen Deficiency in Natural Accessions of Arabidopsis thaliana

    Science.gov (United States)

    De Gernier, Hugues; De Pessemier, Jérôme; Xu, Jiajia; Cristescu, Simona M.; Van Der Straeten, Dominique; Verbruggen, Nathalie; Hermans, Christian

    2016-01-01

    An original approach to develop sustainable agriculture with less nitrogen fertilizer inputs is to tackle the cross-talk between nitrogen nutrition and plant growth regulators. In particular the gaseous hormone, ethylene, is a prime target for that purpose. The variation of ethylene production in natural accessions of the model species Arabidopsis thaliana was explored in response to the nitrate supply. Ethylene was measured with a laser-based photoacoustic detector. First, experimental conditions were established with Columbia-0 (Col-0) accession, which was grown in vitro on horizontal plates across a range of five nitrate concentrations (0.5, 1, 2.5, 5, or 10 mM). The concentrations of 1 and 10 mM nitrate were retained for further characterization. Along with a decrease of total dry biomass and higher biomass allocation to the roots, the ethylene production was 50% more important at 1 mM than at 10 mM nitrate. The total transcript levels of 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASES (ACS) in roots and those of ACC OXIDASES (ACO) in shoots increased by 100% between the same treatments. This was mainly due to higher transcript levels of ACS6 and of ACO2 and ACO4 respectively. The assumption was that during nitrogen deficiency, the greater biomass allocation in favor of the roots was controlled by ethylene being released in the shoots after conversion of ACC originating from the roots. Second, biomass and ethylene productions were measured in 20 additional accessions. Across all accessions, the total dry biomass and ethylene production were correlated negatively at 1 mM but positively at 10 mM nitrate. Furthermore, polymorphism was surveyed in ACC and ethylene biosynthesis genes and gene products among accessions. Very few substitutions modifying the amino acids properties in conserved motifs of the enzymes were found in the accessions. Natural variation of ethylene production could be further explored to improve Nitrogen Use Efficiency (NUE), in particular by

  7. Vitamin A deficiency increases protein catabolism and induces urea cycle enzymes in rats.

    Science.gov (United States)

    Esteban-Pretel, Guillermo; Marín, M Pilar; Cabezuelo, Francisco; Moreno, Verónica; Renau-Piqueras, Jaime; Timoneda, Joaquín; Barber, Teresa

    2010-04-01

    Chronic vitamin A deficiency induces a substantial delay in the rates of weight and height gain in both humans and experimental animals. This effect has been associated with an impaired nutrient metabolism and loss of body protein. Therefore, we analyzed the effect of vitamin A deficiency on endogenous proteolysis and nitrogen metabolism and its reversibility with all-trans retinoic acid (RA). Male weanling rats, housed in pairs, were pair-fed a vitamin A-deficient (VAD) or control diet until they were 60 d old. A group of deficient rats were further treated with daily intraperitoneal injections of all-trans RA for 10 d. Final body and tissue (i.e. liver and heart) weights were significantly lower and tissue:body weight ratios were similar in VAD rats and in controls. Conversely, the epididymal white fat:body weight ratio and the plasma concentrations of alanine aminotransferase and adiponectin were significantly higher in VAD rats, which also had hepatic macrovesicular lipid accumulations. Plasma and gastrocnemius muscle 3-methylhistidine, urine nitrogen, and plasma and urine urea concentrations were all significantly higher in the VAD group. The expression of the genes encoding urea cycle enzymes and their activities increased in VAD livers. These changes were partially reverted by all-trans RA. We propose that fuel partitioning in vitamin A deficiency may shift from fatty acids to protein catabolism as an energy source. Our results emphasize the importance of vitamin A on the energy balance control system and they provide an explanation for the role of vitamin A in protein turnover, development, and growth.

  8. Identification of gene fragments related to nitrogen deficiency in Eichhornia crassipes (Pontederiaceae).

    Science.gov (United States)

    Fu, Minghui; Jiang, Lihua; Li, Yuanmei; Yan, Guohua; Zheng, Lijun; Jinping, Peng

    2014-12-01

    Eichhornia crassipes is an aquatic plant native to the Amazon River Basin. It has become a serious weed in freshwater habitats in rivers, lakes and reservoirs both in tropical and warm temperate areas worldwide. Some research has stated that it can be used for water phytoremediation, due to its strong assimilation of nitrogen and phosphorus, and the accumulation of heavy metals, and its growth and spread may play an important role in environmental ecology. In order to explore the molecular mechanism of E. crassipes to responses to nitrogen deficiency, we constructed forward and reversed subtracted cDNA libraries for E. crassipes roots under nitrogen deficient condition using a suppressive subtractive hybridization (SSH) method. The forward subtraction included 2,100 clones, and the reversed included 2,650 clones. One thousand clones were randomly selected from each library for sequencing. About 737 (527 unigenes) clones from the forward library and 757 (483 unigenes) clones from the reversed library were informative. Sequence BlastX analysis showed that there were more transporters and adenosylhomocysteinase-like proteins in E. crassipes cultured in nitrogen deficient medium; while, those cultured in nitrogen replete medium had more proteins such as UBR4-like e3 ubiquitin-protein ligase and fasciclin-like arabinogalactan protein 8-like, as well as more cytoskeletal proteins, including actin and tubulin. Cluster of Orthologous Group (COG) analysis also demonstrated that in the forward library, the most ESTs were involved in coenzyme transportation and metabolism. In the reversed library, cytoskeletal ESTs were the most abundant. Gene Ontology (GO) analysis categories demonstrated that unigenes involved in binding, cellular process and electron carrier were the most differentially expressed unigenes between the forward and reversed libraries. All these results suggest that E. crassipes can respond to different nitrogen status by efficiently regulating and controlling

  9. Gene Deletions Resulting in Increased Nitrogen Release by Azotobacter vinelandii: Application of a Novel Nitrogen Biosensor

    Science.gov (United States)

    Eberhart, Lauren J.; Ohlert, Janet M.; Knutson, Carolann M.; Plunkett, Mary H.

    2015-01-01

    Azotobacter vinelandii is a widely studied model diazotrophic (nitrogen-fixing) bacterium and also an obligate aerobe, differentiating it from many other diazotrophs that require environments low in oxygen for the function of the nitrogenase. As a free-living bacterium, A. vinelandii has evolved enzymes and transporters to minimize the loss of fixed nitrogen to the surrounding environment. In this study, we pursued efforts to target specific enzymes and further developed screens to identify individual colonies of A. vinelandii producing elevated levels of extracellular nitrogen. Targeted deletions were done to convert urea into a terminal product by disrupting the urease genes that influence the ability of A. vinelandii to recycle the urea nitrogen within the cell. Construction of a nitrogen biosensor strain was done to rapidly screen several thousand colonies disrupted by transposon insertional mutagenesis to identify strains with increased extracellular nitrogen production. Several disruptions were identified in the ammonium transporter gene amtB that resulted in the production of sufficient levels of extracellular nitrogen to support the growth of the biosensor strain. Further studies substituting the biosensor strain with the green alga Chlorella sorokiniana confirmed that levels of nitrogen produced were sufficient to support the growth of this organism when the medium was supplemented with sufficient sucrose to support the growth of the A. vinelandii in coculture. The nature and quantities of nitrogen released by urease and amtB disruptions were further compared to strains reported in previous efforts that altered the nifLA regulatory system to produce elevated levels of ammonium. These results reveal alternative approaches that can be used in various combinations to yield new strains that might have further application in biofertilizer schemes. PMID:25888177

  10. Identification of gene fragments related to nitrogen deficiency in Eichhornia crassipes (Pontederiaceae

    Directory of Open Access Journals (Sweden)

    Fu Minghui

    2014-12-01

    Full Text Available Eichhornia crassipes is an aquatic plant native to the Amazon River Basin. It has become a serious weed in freshwater habitats in rivers, lakes and reservoirs both in tropical and warm temperate areas worldwide. Some research has stated that it can be used for water phytoremediation, due to its strong assimilation of nitro- gen and phosphorus, and the accumulation of heavy metals, and its growth and spread may play an important role in environmental ecology. In order to explore the molecular mechanism of E. crassipes to responses to nitrogen deficiency, we constructed forward and reversed subtracted cDNA libraries for E. crassipes roots under nitrogen deficient condition using a suppressive subtractive hybridization (SSH method. The forward subtraction included 2 100 clones, and the reversed included 2 650 clones. One thousand clones were randomly selected from each library for sequencing. About 737 (527 unigenes clones from the forward library and 757 (483 unigenes clones from the reversed library were informative. Sequence BlastX analysis showed that there were more transporters and adenosylhomocysteinase-like proteins in E. crassipes cultured in nitrogen deficient medium; while, those cultured in nitrogen replete medium had more proteins such as UBR4-like e3 ubiquitin- protein ligase and fasciclin-like arabinogalactan protein 8-like, as well as more cytoskeletal proteins, including actin and tubulin. Cluster of Orthologous Group (COG analysis also demonstrated that in the forward library, the most ESTs were involved in coenzyme transportation and metabolism. In the reversed library, cytoskeletal ESTs were the most abundant. Gene Ontology (GO analysis categories demonstrated that unigenes involved in binding, cellular process and electron carrier were the most differentially expressed unigenes between the forward and reversed libraries. All these results suggest that E. crassipes can respond to different nitrogen status by efficiently

  11. Chemical oceanography. Increasing anthropogenic nitrogen in the North Pacific Ocean.

    Science.gov (United States)

    Kim, Il-Nam; Lee, Kitack; Gruber, Nicolas; Karl, David M; Bullister, John L; Yang, Simon; Kim, Tae-Wook

    2014-11-28

    The recent increase in anthropogenic emissions of reactive nitrogen from northeastern Asia and the subsequent enhanced deposition over the extensive regions of the North Pacific Ocean (NPO) have led to a detectable increase in the nitrate (N) concentration of the upper ocean. The rate of increase of excess N relative to phosphate (P) was found to be highest (~0.24 micromoles per kilogram per year) in the vicinity of the Asian source continent, with rates decreasing eastward across the NPO, consistent with the magnitude and distribution of atmospheric nitrogen deposition. This anthropogenically driven increase in the N content of the upper NPO may enhance primary production in this N-limited region, potentially leading to a long-term change of the NPO from being N-limited to P-limited. Copyright © 2014, American Association for the Advancement of Science.

  12. Effects of nitrogen-deficiency on efficiency of light-harvesting apparatus in radish.

    Science.gov (United States)

    Cetner, M D; Kalaji, H M; Goltsev, V; Aleksandrov, V; Kowalczyk, K; Borucki, W; Jajoo, A

    2017-10-01

    Nitrogen starvation has been stated to reduce chlorophyll a and accessory pigments, decrease photosynthetic efficiency, as well as modify chloroplast thylakoid membranes. However, the impact of N-deficiency on light-dependent reactions of photosynthesis has not been well understood. In this study, efficiency and structure of light-harvesting complex under N-deficiency conditions were investigated in two radish cultivars (Raphanus sativus var. sativus 'Fluo HF1' and 'Suntella F1'). Light-dependent reactions of photosynthesis were investigated by measuring in vivo chlorophyll a prompt fluorescence signal. Acquired data were utilised in two ways: by plotting fast induction curves and calculating OJIP-test biophysical parameters. Detailed analysis of difference curves as well as OJIP-test results showed that major disturbances were associated with photosystem II and its subunits, including decoupling of light-harvesting complexes, dysfunction of oxygen-evolving complex, and reaction centres inactivation. The maximum quantum yield of photosystem II primary photochemistry was severely restricted, causing an inhibition in electron transport through successive protein complexes in the thylakoid membrane. Structural changes were demonstrated by recording images using Transmission Electron Microscopy (TEM). TEM investigations showed intensive starch accumulation under N-deficiency. Rare thylakoid stacks distributed in tiny layers of stroma around grains and chloroplast periphery were observed in cells of N-deficient plants. The application of principal component analysis (PCA) on OJIP-test results allowed characterizing the dynamics of stress response and separating parameters according to their influence on plants stress response. 'Suntella F1' genotype was found to be more sensitive to nitrogen deficiency as compared to 'Fluo HF1' genotype. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Effect of oxygen deficiency on nitrogen assimilation and amino acid metabolism of soybean root segments.

    Science.gov (United States)

    Oliveira, Halley Caixeta; Sodek, Ladaslav

    2013-02-01

    Plants submitted to O(2) deficiency present a series of biochemical modifications, affecting overall root metabolism. Here, the effect of hypoxia on the metabolic fate of (15)N derived from (15)NO(3)(-), (15)NO(2)(-) and (15)NH(4)(+) in isolated soybean root segments was followed by gas chromatography-mass spectrometry, to provide a detailed analysis of nitrogen assimilation and amino acid biosynthesis under hypoxia. O(2) deficiency decreased the uptake of the nitrogen sources from the solution, as ratified by the lower (15)NO(3)(-) and (15)NH(4)(+) enrichment in the root segments. Moreover, analysis of endogenous NO(2)(-) and (15)NH(4)(+) levels suggested a slower metabolism of these ions under hypoxia. Accordingly, regardless of the nitrogen source, hypoxia reduced total (15)N incorporation into amino acids. Analysis of (15)N enrichment patterns and amino acid levels suggest a redirecting of amino acid metabolism to alanine and γ-aminobutyric acid synthesis under hypoxia and a differential sensitivity of individual amino acid pathways to this stress. Moreover, the role of glutamine synthetase in nitrogen assimilation both under normoxia and hypoxia was ratified. In comparison with (15)NH(4)(+), (15)NO(2)(-) assimilation into amino acids was more strongly affected by hypoxia and NO(2)(-) accumulated in root segments during this stress, indicating that nitrite reductase may be an additional limiting step. NO(2)(-) accumulation was associated with a higher nitric oxide emission. (15)NO(3)(-) led to much lower (15)N incorporation in both O(2) conditions, probably due to the limited nitrate reductase activity of the root segments. Overall, the present work shows that profound alterations of root nitrogen metabolism occur during hypoxic stress.

  14. Selenium deficiency risk predicted to increase under future climate change

    Science.gov (United States)

    Jones, Gerrad D.; Droz, Boris; Greve, Peter; Gottschalk, Pia; Poffet, Deyan; McGrath, Steve P.; Seneviratne, Sonia I.; Smith, Pete; Winkel, Lenny H. E.

    2017-01-01

    Deficiencies of micronutrients, including essential trace elements, affect up to 3 billion people worldwide. The dietary availability of trace elements is determined largely by their soil concentrations. Until now, the mechanisms governing soil concentrations have been evaluated in small-scale studies, which identify soil physicochemical properties as governing variables. However, global concentrations of trace elements and the factors controlling their distributions are virtually unknown. We used 33,241 soil data points to model recent (1980–1999) global distributions of Selenium (Se), an essential trace element that is required for humans. Worldwide, up to one in seven people have been estimated to have low dietary Se intake. Contrary to small-scale studies, soil Se concentrations were dominated by climate–soil interactions. Using moderate climate-change scenarios for 2080–2099, we predicted that changes in climate and soil organic carbon content will lead to overall decreased soil Se concentrations, particularly in agricultural areas; these decreases could increase the prevalence of Se deficiency. The importance of climate–soil interactions to Se distributions suggests that other trace elements with similar retention mechanisms will be similarly affected by climate change. PMID:28223487

  15. ACAT1 deficiency increases cholesterol synthesis in mouse peritoneal macrophages.

    Science.gov (United States)

    Dove, Dwayne E; Su, Yan Ru; Swift, Larry L; Linton, MacRae F; Fazio, Sergio

    2006-06-01

    Acyl-coenzyme A:cholesterol acyltransferase (ACAT) esterifies free cholesterol and stores cholesteryl esters in lipid droplets. Macrophage ACAT1 deficiency results in increased atherosclerotic lesion area in hyperlipidemic mice via disrupted cholesterol efflux, increased lipoprotein uptake, accumulation of intracellular vesicles, and accelerated apoptosis. The objective of this study was to determine whether lipid synthesis is affected by ACAT1. The synthesis, esterification, and efflux of new cholesterol were measured in peritoneal macrophages from ACAT1(-/-) mice. Cholesterol synthesis was increased by 134% (p=0.001) in ACAT1(-/-) macrophages compared to wildtype macrophages. Increased synthesis resulted in a proportional increase in the efflux of newly synthesized cholesterol. Although the esterification of new cholesterol was reduced by 93% (pSREBP1a mRNA was increased 6-fold in ACAT1(-/-) macrophages compared to wildtype macrophages, suggesting an up-regulation of cholesterol and fatty acid synthesis in ACAT1(-/-) macrophages. Increased cholesterol synthesis and up-regulation of SREBP in ACAT1(-/-) macrophages suggests that ACAT1 affects the regulation of lipid metabolism in macrophages. This change in cholesterol homeostasis may contribute to the atherogenic potential of ACAT1(-/-) macrophages.

  16. CDYL Deficiency Disrupts Neuronal Migration and Increases Susceptibility to Epilepsy.

    Science.gov (United States)

    Qin, Rui; Cao, Shuai; Lyu, Tianjie; Qi, Cai; Zhang, Weiguang; Wang, Yun

    2017-01-10

    During brain development, the correct migration of newborn neurons is one of the determinants of circuit formation, and neuronal migration defects may lead to neurological and psychiatric disorders. The molecular mechanisms underlying neuronal migration and related disorders are poorly understood. Here, we report that Chromodomain Y-like (CDYL) is critical for neuronal migration in mice. Knocking down CDYL caused neuronal migration defects and disrupted both mobility and multipolar-to-bipolar transition of migrating neurons. We find that CDYL regulates neuronal migration by transcriptionally repressing RhoA. In addition, CDYL deficiency increased the excitability of cortical pyramidal neurons and the susceptibility of mice to convulsant-induced seizures. These results demonstrate that CDYL is a regulator of neuronal migration and shed light on the pathogenesis of seizure-related neurodevelopmental disorders. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. CCR5 deficiency increased susceptibility to lipopolysaccharide-induced acute renal injury.

    Science.gov (United States)

    Lee, Dong Hun; Park, Mi Hee; Hwang, Chul Ju; Hwang, Jae Yeon; Yoon, Hae Suk; Yoon, Do Young; Hong, Jin Tae

    2016-05-01

    C-C chemokine receptor 5 (CCR5) regulates leukocyte chemotaxis and activation, and its deficiency exacerbates development of nephritis. Therefore, we investigated the role of CCR5 during lipopolysaccharide (LPS)-induced acute kidney injury. CCR5-deficient (CCR5-/-) and wild-type (CCR5+/+) mice, both aged about 10 months, had acute renal injury induced by intraperitoneal injection of LPS (10 mg/kg). Compared with CCR5+/+ mice, CCR5-/- mice showed increased mortality and renal injury, including elevated creatinine and blood urea nitrogen levels, following LPS challenge. Compared to CCR5+/+ mice, CCR5-/- mice also exhibited greater increases in the serum concentrations of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β following LPS challenge. Furthermore, infiltration of macrophages and neutrophils, expression of intracellular adhesion molecule (ICAM)-1, and the number of apoptotic cells were more greatly increased by LPS treatment in CCR5-/- mice than in CCR5+/+ mice. The concentrations of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β were also significantly increased in the kidney of CCR5-/- mice after LPS challenge. Moreover, primary kidney cells from CCR5-/- mice showed greater increases in TNF-α production and p38 MAP kinase activation following treatment with LPS compared with that observed in the cells from CCR5+/+ mice. LPS-induced TNF-α production and apoptosis in the primary kidney cells from CCR5-/- mice were inhibited by treatment with p38 MAP kinase inhibitor. These results suggest that CCR5 deficiency increased the production of TNF-α following LPS treatment through increased activation of the p38 pathway in the kidney, resulting in renal apoptosis and leukocyte infiltration and led to exacerbation of LPS-induced acute kidney injury.

  18. AMPD3-deficient mice exhibit increased erythrocyte ATP levels but anemia not improved due to PK deficiency.

    Science.gov (United States)

    Cheng, Jidong; Morisaki, Hiroko; Toyama, Keiko; Ikawa, Masahito; Okabe, Masaru; Morisaki, Takayuki

    2012-11-01

    AMP deaminase (AMPD) catalyzes AMP to IMP and plays an important role in energy charge and nucleotide metabolism. Human AMPD3 deficiency is a type of erythrocyte-specific enzyme deficiency found in individuals without clinical symptoms, although an increased level of ATP in erythrocytes has been reported. To better understand the physiological and pathological roles of AMPD3 deficiency, we established a line of AMPD3-deficient [A3(-/-)] mice. No AMPD activity and a high level of ATP were observed in erythrocytes of these mice, similar to human RBC-AMPD3 deficiency, while other characteristics were unremarkable. Next, we created AMPD3 and pyruvate kinase (PK) double-deficient [PKA(-/-,-/-)] mice by mating A3(-/-) mice with CBA-Pk-1slc/Pk-1slc mice [PK(-/-)], a spontaneous PK-deficient strain showing hemolytic anemia. In PKA(-/-,-/-) mice, the level of ATP in red blood cells was increased 1.5 times as compared to PK(-/-) mice, although hemolytic anemia in those animals was not improved. In addition, we observed osmotic fragility of erythrocytes in A3(-/-) mice under fasting conditions. In contrast, the ATP level in erythrocytes was elevated in A3(-/-) mice as compared to the control. In conclusion, AMPD3 deficiency increases the level of ATP in erythrocytes, but does not improve anemia due to PK deficiency and leads to erythrocyte dysfunction.

  19. Nutrition deficiency increases the risk of stomach cancer mortality

    Directory of Open Access Journals (Sweden)

    Da Li Qing

    2012-07-01

    Full Text Available Abstract Background The purpose of the study is to determine whether exposure to malnutrition during early life is associated with increased risk of stomach cancer in later life. Methods The design protocol included analyzing the trend of gastric cancer mortality and nutrition and evaluating the association between nutrient deficiency in early life and the risk of gastric cancer by hierarchical age–period–birth cohort (APC analysis using general log-linear Poisson models and to compare the difference between birth cohorts who were exposed to the 1959–1961 Chinese famine and those who were not exposed to the famine. Data on stomach cancer mortality from 1970 to 2009 and the dietary patterns from 1955 to 1985 which included the 1959–1961 Chinese famine period in the Zhaoyuan County population were obtained. The nutrition information was collected 15 years prior to the mortality data as based on the latest reference of disease incubation. Results APC analysis revealed that severe nutrition deficiency during early life may increase the risk of stomach cancer. Compared with the 1960–1964 birth cohort, the risk for stomach cancer in all birth cohorts from 1900 to 1959 significantly increased; compared with the 1970–1974 cohort, the risk for stomach cancer in the 1975–1979 cohort significantly increased, whereas the others had a steadily decreased risk; compared with 85–89 age group in the 2005–2009 death survey, the ORs decreased with younger age and reached significant levels for the 50–54 age group after adjusting the confounding factors. The 1930 to 1964 group (exposed to famine had a higher mortality rate than the 1965 to 1999 group (not exposed to famine. For males, the relative risk (RR was 2.39 and the 95% confidence interval (CI was 1.51 to 3.77. For females, RR was 1.64 and 95% CI was 1.02 to 2.62. Conclusion The results of the present study suggested that prolonged malnutrition during early life may increase the risk of

  20. THE EFFECT OF SALINITY AND NITROGEN DEFICIENCY ON THE CHANGES IN SELECTED PHYSIOLOGICAL PARAMETERS OF COMMON BEAN (PHASEOLEUS VULGARIS L. GROWN IN HYDROPONIC CULTURES

    Directory of Open Access Journals (Sweden)

    Jacek Wróbel

    2016-09-01

    Full Text Available This study aimed at evaluating the physiological activity of common bean grown under the conditions of stress being induced by salinity and nitrogen deficiency and its lack in substrate. Three series of two-factorial hydroponic experiment with the common bean (Phaseolus vulgaris L. cultivar Basta were carried out from May to July in 2013–2014. The first experimental factor was three levels of nitrogen content in a Hoagland hydroponic medium (level 1 – a complete medium, level 2 – without 50% N, level 3 – without 100% N. The second experimental factor was three levels of medium salinity (level 1 – no NaCl addition, level 2 – 30 mM NaCl addition, level 3 – 50 mM NaCl addition. Nitrogen deficiency in a Hoagland hydroponic medium, together with increased salinity level, significantly affected the changes in the physiological parameters of the common bean cultivar Basta being tested, i.e. assimilation pigment concentration (chlorophyll-a, chlorophyll-b and chlorophyll-a+b and carotenoids, assimilation and transpiration intensities, and RWC (relative water content. The 50% nitrogen deficiency in medium induced a significant increase in the concentration of all assimilation pigments in common bean leaves and was by far the highest among the experimental variants being tested. A significant decrease in the content of assimilation pigments was observed in the hydroponic mediums without nitrogen and salined with 30 and 50 mM sodium chloride. The interaction of these two experimental factors being analysed, i.e. nitrogen deficiency and its lack in a Hoagland hydroponic medium and its salinity, significantly decreased the intensity of assimilation in bean leaves, while a significant increase in transpiration was observed in the variant without nitrogen and with 50 mM NaCl. The experimental variants being tested had a significant effect on the changes in leaf water balance of the common bean cultivar being tested. Salinity, in interaction with

  1. Increased vascular sympathetic modulation in mice with Mas receptor deficiency.

    Science.gov (United States)

    Rabello Casali, Karina; Ravizzoni Dartora, Daniela; Moura, Marina; Bertagnolli, Mariane; Bader, Michael; Haibara, Andrea; Alenina, Natalia; Irigoyen, Maria Claudia; Santos, Robson A

    2016-01-01

    The angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1-7)/Mas axis could modulate the heart rate (HR) and blood pressure variabilities (BPV) which are important predictors of cardiovascular risk and provide information about the autonomic modulation of the cardiovascular system. Therefore we investigated the effect of Mas deficiency on autonomic modulation in wild type and Mas-knockout (KO) mice. Blood pressure was recorded at high sample rate (4000 Hz). Stationary sequences of 200-250 beats were randomly chosen. Frequency domain analysis of HR and BPV was performed with an autoregressive algorithm on the pulse interval sequences and on respective systolic sequences. The KO group presented an increase of systolic arterial pressure (SAP; 127.26±11.20 vs 135.07±6.98 mmHg), BPV (3.54±1.54 vs 5.87±2.12 mmHg(2)), and low-frequency component of systolic BPV (0.12±0.11 vs 0.47±0.34 mmHg(2)). The deletion of Mas receptor is associated with an increase of SAP and with an increased BPV, indicating alterations in autonomic control. Increase of sympathetic vascular modulation in absence of Mas evidences the important role of Ang-(1-7)/Mas on cardiovascular regulation. Moreover, the absence of significant changes in HR and HRV can indicate an adaptation of autonomic cardiac balance. Our results suggest that the Ang-(1-7)/Mas axis seems more important in autonomic modulation of arterial pressure than HR. © The Author(s) 2016.

  2. A Comparison of the Nitrogen Gas Excess Versus the Fixed Nitrogen Deficit in Two Major Oxygen Deficient Zones of the World

    Science.gov (United States)

    Devol, A. H.; Chang, B. X.

    2006-12-01

    This study compares the nitrogen gas excesses in the oxygen deficient zones (ODZs) of the Eastern Tropical South Pacific (ETSP) and the Arabian Sea. These are two of the three largest ODZs in the world. In the near absence of oxygen, heterotrophic denitrification is the dominant form of respiration in these regions which, coupled to the sheer vastness of the ODZs, makes them a globally significant sink of marine fixed nitrogen. Thus, understanding how nitrogen is cycled in the ODZs is important to understanding the global nitrogen cycle. We measured profiles of nitrogen gas and argon concentrations through the ODZs of the ETSP and the Arabian Sea in the fall of 2005 and 2004, respectively. Nitrogen gas concentrations were normalized to argon concentrations to eliminate variations due to physical changes in the water mass. Any nitrogen gas in excess of the background nitrogen gas concentration was interpreted to be from denitrification. In the Arabian Sea ODZ, we found the nitrogen gas excess up to 18 uM N. Using stoichiometric relationships of nitrate and phosphate specific to the Arabian Sea, previous workers have estimated the nitrate deficit in the Arabian Sea ODZ to be no more than 12 uM N, which is only two-thirds of the nitrogen gas excess. In the ODZ of the ETSP, we found the nitrogen gas excess to be 15 uM N and the estimated nitrate deficit to be comparable, which suggests that in the ETSP, the nitrogen gas excess may be accounted for by the nitrate deficit. In the Arabian Sea ODZ, however, there is 50% more nitrogen in the excess than can be accounted for by the nitrate deficit. Several explanations are possible for this discrepancy, but probably the most significant is the likely greater contribution of nitrogen fixation to the overall productivity of the Arabian Sea compared to the ETSP. Nitrogen fixing bacteria are known to have an elevated N:P relative to the assumed near-Redfieldian organic matter falling into the ODZ. Nitrogen fixation has been

  3. Increased adiposity in annexin A1-deficient mice.

    Directory of Open Access Journals (Sweden)

    Rand T Akasheh

    Full Text Available Production of Annexin A1 (ANXA1, a protein that mediates the anti-inflammatory action of glucocorticoids, is altered in obesity, but its role in modulation of adiposity has not yet been investigated. The objective of this study was to investigate modulation of ANXA1 in adipose tissue in murine models of obesity and to study the involvement of ANXA1 in diet-induced obesity in mice. Significant induction of ANXA1 mRNA was observed in adipose tissue of both C57BL6 and Balb/c mice with high fat diet (HFD-induced obesity versus mice on chow diet. Upregulation of ANXA1 mRNA was independent of leptin or IL-6, as demonstrated by use of leptin-deficient ob/ob mice and IL-6 KO mice. Compared to WT mice, female Balb/c ANXA1 KO mice on HFD had increased adiposity, as indicated by significantly elevated body weight, fat mass, leptin levels, and adipocyte size. Whereas Balb/c WT mice upregulated expression of enzymes involved in the lipolytic pathway in response to HFD, this response was absent in ANXA1 KO mice. A significant increase in fasting glucose and insulin levels as well as development of insulin resistance was observed in ANXA1 KO mice on HFD compared to WT mice. Elevated plasma corticosterone levels and blunted downregulation of 11-beta hydroxysteroid dehydrogenase type 1 in adipose tissue was observed in ANXA1 KO mice compared to diet-matched WT mice. However, no differences between WT and KO mice on either chow or HFD were observed in expression of markers of adipose tissue inflammation. These data indicate that ANXA1 is an important modulator of adiposity in mice, with female ANXA1 KO mice on Balb/c background being more susceptible to weight gain and diet-induced insulin resistance compared to WT mice, without significant changes in inflammation.

  4. Nutritional stress effects under different nitrogen sources on the genes in microalga Isochrysis zhangjiangensis and the assistance of Alteromonas macleodii in releasing the stress of amino acid deficiency.

    Science.gov (United States)

    Wu, Shuang; Zhou, Jiannan; Xin, Yanjuan; Xue, Song

    2015-10-01

    The expressions of nine nitrogen assimilation-associated genes, NRT2, NAR1, NIA2, NIR, GLN2, GLSF, GSN1, GDH, and AAT2, in the microalga Isochrysis zhangjiangensis were investigated to unveil the effects of limitations of various nitrogen sources (NaNO3 , NH4 Cl, NaNO2 , and an amino acid mixture) on the microalgae. The results demonstrated that the NRT2, NAR1, GLN2, GSN1, and AAT2 genes were highly expressed in lipid-rich microalgae under inorganic nitrogen-deficient conditions and they decreased after nitrogen resupply. Significant increases in the expressions of NAR1, GLN2, and GLSF were found in nitrate-depleted microalgae, whereas significant increases in the expressions of NRT2, NAR1, GLN2, and GSN1 were found in nitrite-depleted microalgae. Significant increases in the expressions of only NRT2 and GSN1 were found in ammonium-depleted microalgae (P < 0.05). Except for the NRT2, other genes were expressed at lower levels under amino acid-deficient conditions compared with amino acid-sufficient controls. The expression of the NIA2 gene decreased in nitrogen-depleted microalgae regardless of the initial nitrogen source. However, the results of fatty acid analyses showed that the features of fatty acid profiles followed a similar mode, in which the percentage compositions of C16:0 and C18:1Δ(9) increased in nitrogen-depleted cells and that of C16:1Δ(9) , C18:3Δ(9,12,15) , C18:4Δ(6,9,12,15) , and C18:5Δ(3,6,9,12,15) decreased, regardless of the type of nitrogen source applied. It was also found that the epiphytic bacterium Alteromonas macleodii played a particularly important role in releasing microalgae from the stress of amino acid deficiency. These findings also provide a foundation for regulating microalgal lipid production through manipulation of the nitrogen assimilation-associated genes.

  5. Chronic vitamin C deficiency increases the risk of cardiovascular diseases.

    Science.gov (United States)

    Ginter, E

    2007-01-01

    The studies on experimental animals (guinea pigs, monkeys, fish) have confirmed the important role of ascorbic acid deficiency in the development of hypercholesterolemia and atherosclerosis, but the clinical experience is not quite uniform. Metaanalyses of randomized controlled trials performed on subjects without established vitamin C-deficiency conclud that the evidence of the presence or absence of benefits derived from the ability of ascorbic acid to prevent cardiovascular diseases is not sufficient. This review is an outline of numerous clinical, epidemiological and prospective studies that have found a positive role of vitamin C in the prevention of atherosclerosis. If we admit the possibility that vitamin C deficiency is a significant risk factor of atherogenesis, due to ethical reasons it is impossible to perform long-term controlled trials on subjects with proved vitamin C deficiency, to recommend them not to change their nutrition and lifestyle, and to administer placebo to the control group. Therefore the proof of atherogenic effect of chronic vitamin C deficiency is limited to indirect evidence only. In this review many new data on the positive effects of ascorbic acid on human cardiovascular system are summarized and the mechanisms of its protective influence on blood vessels are discussed (Fig.5, Ref. 45). Full Text (Free, PDF) www.bmj.sk.

  6. Nitrogen-deficient microalgae are rich in cell-surface mannose: potential implications for prey biorecognition by phagotrophic protozoa

    Science.gov (United States)

    Martel, Claire M.

    2009-01-01

    Flow cytometry was used to quantify the abundance of mannose-linked glycoconjugates on microalgae precultured using low- or high-nitrate media. Nitrogen-deficient microalgae were richer in cell-surface mannose than nitrogen-sufficient. Findings are discussed in view of recent research which reveals mannose-specific ‘feeding receptors’ assist prey biorecognition by phagotrophic protozoa that ingest microalgae. PMID:24031323

  7. Increasing nitrogen rates in rice and its effect on plant nutrient composition and nitrogen apparent recovery

    Directory of Open Access Journals (Sweden)

    Juan Hirzel

    2013-12-01

    Full Text Available Rice (Oryza sativa L. is one of the essential foods of the human diet; advances in agronomic crop management can improve productivity and profitability as well as reduce adverse environmental impacts. Nitrogen rates in Chile are generally based on crop yield without considering other agronomic factors. The objective of this experiment was to determine the effect of increasing N rates on plant nutrient composition and N apparent recovery in rice cultivated in five different locations in Chile. The five sites located in central Chile belong to one of the following soil orders: Inceptisol, Alfisol, and Vertisol; they were cropped in field conditions with 'Zafiro-INIA' rice fertilized with 0, 80, and 160 kg N ha-1. Whole-plant total DM, macronutrient composition, and N apparent recovery efficiency (NARE were determined at grain harvest. Results indicate that all evaluated parameters, with the exception of K concentration, were affected by the soil used. Nitrogen rates only affected total DM production and P, K, and Mg concentrations in plants. Phosphorus and K response decreased when N was added to some soils, which is associated with its chemical properties. Magnesium concentration exhibited an erratic effect, but it was not affected by the N rate in most soils. Nitrogen apparent recovery efficiency was not affected by the N rate and accounted for approximately 49% and 41% for 80 and 160 kg N ha-1, respectively. Macronutrient composition was 5.1-7.7 g N, 1.3-1.8 g P, 5.4-10.8 g K, 1.68-2.57 g Ca, and 0.81-1.45 g Mg kg-1 of total DM.

  8. Iron deficiency anemia and increased urinary norepinephrine excretion.

    Science.gov (United States)

    Voorhess, M L; Stuart, M J; Stockman, J A; Oski, F A

    1975-04-01

    Chronic iron deficiency in rats resulted in decreased MAO activity both in vitro and in vivo. Since MAO is an important enzyme in inactivation of catecholamines, urinary excretion of DA, NE, E, MN-NMN, and VMA was measured in 24-hour samples from 11 iron-deficient children before and after treatment with intramuscular iron. Pretreatment NE excretion was abnormally high and returned to normal (P=0.001) within one week of therapy. VMA excretion also was higher before than after treatment (P greater than 0.05), but most values were within the normal range for healthy children of comparable size. There was no significant difference between DA, E, and MN-NMN excretion before and after iron therapy. Anemic, non-iron-deficient children had normal urinary NE, E, and VMA excretion before and after transfusion. These findings suggest that the irritability, lack of attentiveness, and low performance scores of iron-deficient children may be related to alterations in catecholamine metabolic pathways secondary to dependence of MAO on adequate iron stores.

  9. Increasing Nitrogen Use Efficiency of Corn in Midwestern Cropping Systems

    Directory of Open Access Journals (Sweden)

    J.L. Hatfield

    2001-01-01

    Full Text Available Nitrogen (N loss from agricultural systems raises concerns about the potential impact of farming practices on environmental quality. N is a critical input to agricultural production. However, there is little understanding of the interactions among crop water use, N application rates, and soil types. This study was designed to quantify these interactions in corn (Zea mays L. grown in production-size fields in central Iowa on the Clarion-Nicollet-Webster soil association. Seasonal water use varied by soil type and N application rate. Yield varied with N application rate, with the highest average yield obtained at 100 kg ha-1. N use efficiency (NUE decreased with increasing N application rates, having values around 50%. Water use efficiency (WUE decreased as N fertilizer rates increased. Analysis of plant growth patterns showed that in the low organic matter soils (lower water-holding capacities, potential yield was not achieved because of water deficits during the grain-filling period. Using precipitation data coupled with daily water use throughout the season, lower organic matter soils showed these soils began to drain earlier in the spring and continued to drain more water throughout the season. The low NUE in these soils together with increased drainage lead to greater N loss from these soils. Improved management decisions have shown that it is possible to couple water use patterns with N application to increase both WUE and NUE.

  10. Nitrogen deficiency hinders etioplast development in stems of dark-grown pea (Pisum sativum) shoot cultures.

    Science.gov (United States)

    Kósa, Annamária; Preininger, Éva; Böddi, Béla

    2015-11-01

    The effects of nitrogen (N) deprivation were studied in etiolated pea plants (Pisum sativum cv. Zsuzsi) grown in shoot cultures. The average shoot lengths decreased and the stems significantly altered considering their pigment contents, 77 K fluorescence spectra and ultrastructural properties. The protochlorophyllide (Pchlide) content and the relative contribution of the 654-655 nm emitting flash-photoactive Pchlide form significantly decreased. The etioplast inner membrane structure characteristically changed: N deprivation correlated with a decrease in the size and number of prolamellar bodies (PLBs). These results show that N deficiency directly hinders the pigment production, as well as the synthesis of other etioplast inner membrane components in etiolated pea stems. © 2015 Scandinavian Plant Physiology Society.

  11. Accumulation of tetracoumaroyl spermine in Matricaria chamomilla during floral development and nitrogen deficiency.

    Science.gov (United States)

    Eliasová, Adriana; Poracká, Veronika; Pal'ove-Balang, Peter; Imrich, Ján; Repcák, Miroslav

    2012-01-01

    The new natural polyamine conjugate 1N,5N,10N,14N-tetracoumaroyl spermine (tetracoumaroyl spermine) recently isolated from chamomile (Matricaria chamomilla L.) flower heads is applicable for the treatment of several human disorders such as depression and anxiety. High variability in the level of tetracoumaroyl spermine is found in commercial tisanes. Accumulation of tetracoumaroyl spermine was tested during floral development, and nitrogen deficiency was chosen as its putative limiting environmental factor. It was observed that tetracoumaroyl spermine is present mainly in tubular flowers, reaching its maximal content during the 3rd phase of flowering when the corollae of tubular flowers start to open. The later observed decrease could result from a release of pollen that also contains a considerable amount of tetracoumaroyl spermine. It is likely that tetracoumaroyl spermine plays an important role in pollen development, and so, despite overall N-deficiency in the plants, tetracoumaroyl spermine is accumulated at the same or even higher rate than in the flowers of the N-sufficient control.

  12. Decoupling of soil carbon and nitrogen turnover partly explains increased net ecosystem production in response to nitrogen fertilization

    Science.gov (United States)

    Ehtesham, Emad; Bengtson, Per

    2017-04-01

    During the last decade there has been an ongoing controversy regarding the extent to which nitrogen fertilization can increase carbon sequestration and net ecosystem production in forest ecosystems. The debate is complicated by the fact that increased nitrogen availability caused by nitrogen deposition has coincided with increasing atmospheric carbon dioxide concentrations. The latter could further stimulate primary production but also result in increased allocation of carbon to root exudates, which could potentially ‘prime’ the decomposition of soil organic matter. Here we show that increased input of labile carbon to forest soil caused a decoupling of soil carbon and nitrogen cycling, which was manifested as a reduction in respiration of soil organic matter that coincided with a substantial increase in gross nitrogen mineralization. An estimate of the magnitude of the effect demonstrates that the decoupling could potentially result in an increase in net ecosystem production by up to 51 kg C ha-1 day-1 in nitrogen fertilized stands during peak summer. Even if the effect is several times lower on an annual basis, the results still suggest that nitrogen fertilization can have a much stronger influence on net ecosystem production than can be expected from a direct stimulation of primary production alone.

  13. Roles of Group 2 Sigma Factors in Acclimation of the Cyanobacterium Synechocystis sp. PCC 6803 to Nitrogen Deficiency.

    Science.gov (United States)

    Antal, Taras; Kurkela, Juha; Parikainen, Marjaana; Kårlund, Anna; Hakkila, Kaisa; Tyystjärvi, Esa; Tyystjärvi, Taina

    2016-06-01

    Acclimation of cyanobacteria to environmental conditions is mainly controlled at the transcriptional level, and σ factors of the RNA polymerase have a central role in this process. The model cyanobacterium Synechocystis sp. PCC 6803 has four non-essential group 2 σ factors (SigB, SigC, SigD and SigE) that regulate global metabolic responses to various adverse environmental conditions. Here we show that although none of the group 2 σ factors is essential for the major metabolic realignments induced by a short period of nitrogen starvation, the quadruple mutant without any group 2 σ factors and triple mutants missing both SigB and SigD grow slowly in BG-11 medium containing only 5% of the nitrate present in standard BG-11. These ΔsigBCDE, ΔsigBCD and ΔsigBDE strains lost PSII activity rapidly in low nitrogen and accumulated less glycogen than the control strain. An abnormally high glycogen content was detected in ΔsigBCE (SigD is active), while the carotenoid content became high in ΔsigCDE (SigB is active), indicating that SigB and SigD regulate the partitioning of carbon skeletons in low nitrogen. Long-term survival and recovery of the cells after nitrogen deficiency was strongly dependent on group 2 σ factors. The quadruple mutant and the ΔsigBDE strain (only SigC is active) recovered more slowly from nitrogen deficiency than the control strain, and ΔsigBCDE in particular lost viability during nitrogen starvation. Nitrogen deficiency-induced changes in the pigment content of the control strain recovered essentially in 1 d in nitrogen-replete medium, but little recovery occurred in ΔsigBCDE and ΔsigBDE.

  14. Will Dam Removal Increase Nitrogen Flux to Estuaries?

    Directory of Open Access Journals (Sweden)

    Arthur J. Gold

    2016-11-01

    Full Text Available To advance the science of dam removal, analyses of functions and benefits need to be linked to individual dam attributes and effects on downstream receiving waters. We examined 7550 dams in the New England (USA region for possible tradeoffs associated with dam removal. Dam removal often generates improvements for safety or migratory fish passage but might increase nitrogen (N flux and eutrophication in coastal watersheds. We estimated N loading and removal with algorithms using geospatial data on land use, stream flow and hydrography. We focused on dams with reservoirs that increase retention time at specific points of river reaches, creating localized hotspots of elevated N removal. Approximately 2200 dams with reservoirs had potential benefits for N removal based on N loading, retention time and depth. Across stream orders, safety concerns on these N removal dams ranged between 28% and 44%. First order streams constituted the majority of N removal dams (70%, but only 3% of those were classified as high value for fish passage. In cases where dam removal might eliminate N removal function from a particular reservoir, site-specific analyses are warranted to improve N delivery estimates and examine alternatives that retain the reservoir while enhancing fish passage and safety.

  15. CRF1 receptor-deficiency increases cocaine reward.

    Science.gov (United States)

    Contarino, Angelo; Kitchener, Pierre; Vallée, Monique; Papaleo, Francesco; Piazza, Pier-Vincenzo

    2017-01-27

    Stimulant drugs produce reward but also activate stress-responsive systems. The corticotropin-releasing factor (CRF) and the related hypothalamus-pituitary-adrenal (HPA) axis stress-responsive systems are activated by stimulant drugs. However, their role in stimulant drug-induced reward remains poorly understood. Herein, we report that CRF1 receptor-deficient (CRF1-/-), but not wild-type, mice show conditioned place preference (CPP) responses to a relatively low cocaine dose (5 mg/kg, i.p.). Conversely, wild-type, but not CRF1-/-, mice display CPP responses to a relatively high cocaine dose (20 mg/kg, i.p.), indicating that CRF1 receptor-deficiency alters the rewarding effects of cocaine. Acute pharmacological antagonism of the CRF1 receptor by antalarmin also eliminates cocaine reward. Nevertheless, CRF1-/- mice display higher stereotypy responses to cocaine than wild-type mice. Despite the very low plasma corticosterone concentration, CRF1-/- mice show higher nuclear glucocorticoid receptor (GR) levels in the brain region of the hippocampus than wild-type mice. Full rescue of wild-type-like corticosterone and GR circadian rhythm and level in CRF1-/- mice by exogenous corticosterone does not affect CRF1 receptor-dependent cocaine reward but induces stereotypy responses to cocaine. These results indicate a critical role for the CRF1 receptor in cocaine reward, independently of the closely related HPA axis activity.

  16. Vitamin B12 Deficiency Stimulates Osteoclastogenesis via Increased Homocysteine and Methylmalonic Acid

    NARCIS (Netherlands)

    Vaes, B.L.T.; Lute, C.; Blom, H.J.; Bravenboer, N.; Vries, de T.J.; Everts, V.; Dhonukshe-Rutten, R.A.M.; Müller, M.R.; Groot, de C.P.G.M.; Steegenga, W.T.

    2009-01-01

    The risk of nutrient deficiencies increases with age in our modern Western society, and vitamin B12 deficiency is especially prevalent in the elderly and causes increased homocysteine (Hcy) and methylmalonic acid (MMA) levels. These three factors have been recognized as risk factors for reduced bone

  17. Deficiencies

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of all deficiencies currently listed on Nursing Home Compare, including the nursing home that received the deficiency, the associated inspection date,...

  18. Increased risk of iodine deficiency with vegetarian nutrition.

    Science.gov (United States)

    Remer, T; Neubert, A; Manz, F

    1999-01-01

    Observational studies primarily based on diet questionnaires or food records have reported that vegetarians can have a very low I intake. However, analytically ascertained data on the possible degree of I deficiency with this form of diet is lacking. Six healthy adult volunteers participated in the present controlled experimental diet study carried out in four separate 5 d diet periods. The study diets, normal, protein-rich, lactovegetarian, and repeat of the initial normal diet, were almost isoenergetic and contained no fish, sea food, iodized salt or processed foods fortified with I. During the last 48 h of each diet period two 24 h urine samples were obtained from each subject. I analyses were performed in the urine samples and in representative samples taken from all ingested diets. Urinary I excretion was significantly lower with the lactovegetarian diet (36.6 (SD 8.8) micrograms/d) than with the normal and the protein-rich diets (50.2 (SD 14.0) and 61.0 (SD 8.0) micrograms/d respectively). Accordingly, a markedly reduced I intake was confirmed analytically for the lactovegetarian diet (15.6 micrograms/d v. 35.2 and 44.5 micrograms/d respectively). Our results provide experimental confirmation of literature findings indicating that I supply is higher with non-vegetarian than with vegetarian diets. Specifically, the extremely low intake and urinary output of I as analytically determined for one exemplary vegetarian diet, demonstrate that dietary I may be limiting when strict forms of vegetarian dietary practices (no iodized salt, no I supplements) are followed. The present study is, therefore, the first diet-experiment-based pointer to the potential danger of I deficiency disorders due to strict forms of vegetarian nutrition, especially when fruits and vegetables grown in soils with low I levels are ingested.

  19. Differential changes in galactolipid and phospholipid species in soybean leaves and roots under nitrogen deficiency and after nodulation.

    Science.gov (United States)

    Narasimhan, Rama; Wang, Geliang; Li, Maoyin; Roth, Mary; Welti, Ruth; Wang, Xuemin

    2013-12-01

    The availability of nitrogen (N) to plants has a profound impact on carbohydrate and protein metabolism, but little is known about its effect on membrane lipid species. This study examines the changes in galactolipid and phospholipid species in soybean as affected by the availability of N, either supplied to soil or obtained through Bradyrhizobium japonicum nodulation. When N was limited in soil, the content of galactolipids, monogalactosyldiacylglycerol (MGDG) and digalactosyldiacyglycerol (DGDG), decreased drastically in leaves, while a smaller decrease of DGDG was observed in roots. In both leaves and roots, the overall content of different phospholipid classes was largely unchanged by N limitation, although some individual phospholipid molecular species did display significant changes. Nodulation with Bradyrhizobium of soybean grown in N-deficient soil resulted in a large increase in levels of plastidic lipid classes, MGDG, DGDG, and phosphatidylglycerol, along with smaller increases in non-plastidic phospholipids in leaves. Nodulation also led to higher levels of phospholipids in roots without changes in root levels of MGDG and DGDG. Overall, N availability alters lipid content more in leaves than roots and more in galactolipids than phospholipids. Increased N availability leads to increased galactolipid accumulation in leaves, regardless of whether N is supplied from the soil or symbiotic fixation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Effect of different levels of nitrogen deficiency on switchgrass seedling growth

    Institute of Scientific and Technical Information of China (English)

    Yi; Zhu; Xifeng; Fan; Xincun; Hou; Juying; Wu; Tao; Wang

    2014-01-01

    Switchgrass(Panicum virgatum L.) is a warm-season rhizomatous perennial grass that can tolerate diverse abiotic stresses while yielding relatively high biomass, and is considered a leading biofuel feedstock for marginal lands. Nitrogen(N) is crucial for the growth and development of switchgrass, and its tolerance to low N supply and high N use efficiency are very important for its production under poor conditions. The large-scale planting of switchgrass on marginal lands could be an effective approach to solving the problem of feedstock supply for biomass energy. This study used a hydroponic experiment to evaluate the effect of N deficiency on switchgrass seedlings. Three N treatments(0, 0.15, and 1.50 mmol L-1Hoagland’s solution)and six cultivars were used, three of each ecotype(upland and lowland). The results showed that biomass, leaf area, root surface area, net photosynthesis, and total chlorophyll content significantly decreased under low N treatments compared with those in full strength Hoagland’s nutrient solution. However, once established, all plants survived extreme N stress(0 mmol L-1) and, to some extent, were productive. Cultivar Kanlow performed best of the six cultivars under stress. Significant interactions between stress treatment and cultivars showed that breeding for cultivars with high yield and superior performance under N deficiency is warranted. The lowland outperformed the upland ecotypes under stress, suggesting that lowland cultivars may survive and be productive under a wider range of stress conditions.However, given the better adaptability of lowland ecotypes to hydroponic cultivation, further study is needed.

  1. Exogenous Melatonin Improves Plant Iron Deficiency Tolerance via Increased Accumulation of Polyamine-Mediated Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Cheng Zhou

    2016-10-01

    Full Text Available Melatonin has recently been demonstrated to play important roles in the regulation of plant growth, development, and abiotic and biotic stress responses. However, the possible involvement of melatonin in Fe deficiency responses and the underlying mechanisms remained elusive in Arabidopsis thaliana. In this study, Fe deficiency quickly induced melatonin synthesis in Arabidopsis plants. Exogenous melatonin significantly increased the soluble Fe content of shoots and roots, and decreased the levels of root cell wall Fe bound to pectin and hemicellulose, thus alleviating Fe deficiency-induced chlorosis. Intriguingly, melatonin treatments induced a significant increase of nitric oxide (NO accumulation in roots of Fe-deficient plants, but not in those of polyamine-deficient (adc2-1 and d-arginine-treated plants. Moreover, the melatonin-alleviated leaf chlorosis was blocked in the polyamine- and NO-deficient (nia1nia2noa1 and c-PTIO-treated plants, and the melatonin-induced Fe remobilization was largely inhibited. In addition, the expression of some Fe acquisition-related genes, including FIT1, FRO2, and IRT1 were significantly up-regulated by melatonin treatments, whereas the enhanced expression of these genes was obviously suppressed in the polyamine- and NO-deficient plants. Collectively, our results provide evidence to support the view that melatonin can increase the tolerance of plants to Fe deficiency in a process dependent on the polyamine-induced NO production under Fe-deficient conditions.

  2. Responses of barley root and shoot proteomes to long‐term nitrogen deficiency, short‐term nitrogen starvation and ammonium

    DEFF Research Database (Denmark)

    Laurell Blom Møller, Anders; Pedas, Pai; Andersen, Birgit

    2011-01-01

    plants grown hydroponically for 33 d with 5 mm nitrate, plants grown under N deficiency (0.5 mm nitrate, 33 d) or short‐term N starvation (28 d with 5 mm nitrate followed by 5 d with no N source) were compared. N deficiency caused changes in C and N metabolism and ascorbate‐glutathione cycle enzymes...

  3. The effects of nitrogen form on root morphological and physiological adaptations of maize, white lupin and faba bean under phosphorus deficiency

    Science.gov (United States)

    Liu, Haitao; Tang, Caixian; Li, Chunjian

    2016-01-01

    Root morphological/physiological modifications are important for phosphorus (P) acquisition of plants under P deficiency, but strategies differ among plant species. Detailed studies on the response of maize roots to P deficiency are limited. Nitrogen (N) form influences root morphology/physiology, and thus may influence root responses to P deficiency. This work investigated adaptive mechanisms of maize roots to low P by comparison with white lupin and faba bean supplied with two N forms. Plants were grown for 7–16 days in hydroponics with sufficient (250 µmol L−1) and deficient P supply (1 µmol L−1) under supply of NH4NO3 or Ca(NO3)2. Plant growth and P uptake were measured, and release of protons and organic acid anions, and acid phosphatase activity in the root were monitored. The results showed that P deficiency significantly decreased shoot growth while increased root growth and total root length of maize and faba bean, but not white lupin. It enhanced the release of protons and organic acid anions, and acid phosphatase activity, from the roots of both legumes but not maize. Compared with Ca(NO3)2, NH4NO3 dramatically increased proton release by roots but did not alter root morphology or physiology of the three species in response to low P. It is concluded that the N form did not fundamentally change root morphological/physiological responses of the three species to P deficiency. Morphological variation in maize and morpho-physiological modifications in white lupin and faba bean were the main adaptive strategies to P deficiency. PMID:27519912

  4. Condensed tannins increase nitrogen recovery by trees following insect defoliation.

    Science.gov (United States)

    Madritch, Michael D; Lindroth, Richard L

    2015-10-01

    While the importance of plant secondary metabolites to belowground functioning is gaining recognition, the perception remains that secondary metabolites are produced for herbivore defense, whereas their belowground impacts are ecological by-products, or 'afterlife' effects. However, plants invest a significant amount of resources into production of secondary metabolites that have minimal effects on herbivore resistance (e.g. condensed tannins and insect herbivores). We show that genetically mediated variation in condensed tannin concentration is correlated with plant nitrogen recovery following a severe defoliation event. We used single-tree mesocosms labeled with (15) N to track nitrogen through both the frass and litter cycling pathways. High concentrations of leaf tannins in Populus tremuloides were correlated with (15) N recovery from frass within the same growing season and in the following growing season. Likewise, leaf tannin concentrations were also correlated with (15) N recovery from the litter of defoliated trees in the growing season following the defoliation event. Conversely, tannins were not well correlated with nitrogen uptake under conditions of nominal herbivory. Our results suggest that tannins may confer benefits in response to herbivore pressure through conserved belowground nitrogen cycling, rather than via defensive properties. Consequently, tannins may be considered as chemical mediators of tolerance rather than resistance.

  5. Use of genotype-environment interactions to elucidate the pattern of maize root plasticity to nitrogen deficiency.

    Science.gov (United States)

    Li, Pengcheng; Zhuang, Zhongjuan; Cai, Hongguang; Cheng, Shuai; Soomro, Ayaz Ali; Liu, Zhigang; Gu, Riliang; Mi, Guohua; Yuan, Lixing; Chen, Fanjun

    2016-03-01

    Maize (Zea mays L.) root morphology exhibits a high degree of phenotypic plasticity to nitrogen (N) deficiency, but the underlying genetic architecture remains to be investigated. Using an advanced BC4 F3 population, we investigated the root growth plasticity under two contrasted N levels and identified the quantitative trait loci (QTLs) with QTL-environment (Q × E) interaction effects. Principal components analysis (PCA) on changes of root traits to N deficiency (ΔLN-HN) showed that root length and biomass contributed for 45.8% in the same magnitude and direction on the first PC, while root traits scattered highly on PC2 and PC3. Hierarchical cluster analysis on traits for ΔLN-HN further assigned the BC4 F3 lines into six groups, in which the special phenotypic responses to N deficiency was presented. These results revealed the complicated root plasticity of maize in response to N deficiency that can be caused by genotype-environment (G × E) interactions. Furthermore, QTL mapping using a multi-environment analysis identified 35 QTLs for root traits. Nine of these QTLs exhibited significant Q × E interaction effects. Taken together, our findings contribute to understanding the phenotypic and genotypic pattern of root plasticity to N deficiency, which will be useful for developing maize tolerance cultivars to N deficiency.

  6. Use of genotype-environment interactions to elucidate the pattern of maize root plasticity to nitrogen deficiency

    Institute of Scientific and Technical Information of China (English)

    Pengcheng Li; Fanjun Chen; Zhongjuan Zhuang; Hongguang Cai; Shuai Cheng; Ayaz Ali Soomro; Zhigang Liu; Riliang Gu; Guohua Mi; Lixing Yuan

    2016-01-01

    Maize (Zea mays L.) root morphology exhibits a high degree of phenotypic plasticity to nitrogen (N) deficiency, but the underlying genetic architecture remains to be investigated. Using an advanced BC4F3 population, we investigated the root growth plasticity under two contrasted N levels and identified the quantitative trait loci (QTLs) with QTL-environment (Q ? E) interaction effects. Principal components analysis (PCA) on changes of root traits to N deficiency (DLN-HN) showed that root length and biomass contributed for 45.8%in the same magnitude and direction on the first PC, while root traits scattered highly on PC2 and PC3. Hierarchical cluster analysis on traits for DLN-HN further assigned the BC4F3 lines into six groups, in which the special phenotypic responses to N deficiency was presented. These results revealed the complicated root plasticity of maize in response to N deficiency that can be caused by genotype-environment (G ? E) interactions. Furthermore, QTL mapping using a multi-environment analysis identified 35 QTLs for root traits. Nine of these QTLs exhibited significant Q ? E interaction effects. Taken together, our findings contribute to under-standing the phenotypic and genotypic pattern of root plasticity to N deficiency, which will be useful for developing maize tolerance cultivars to N deficiency.

  7. No evidence that chronic nitrogen additions increase photosynthesis in mature sugar maple forests.

    Science.gov (United States)

    Talhelm, A F; Pregitzer, K S; Burton, A J

    2011-10-01

    Atmospheric nitrogen (N) deposition can increase forest growth. Because N deposition commonly increases foliar N concentrations, it is thought that this increase in forest growth is a consequence of enhanced leaf-level photosynthesis. However, tests of this mechanism have been infrequent, and increases in photosynthesis have not been consistently observed in mature forests subject to chronic N deposition. In four mature northern hardwood forests in the north-central United States, chronic N additions (30 kg N ha(-1) yr(-1) as NaNO3 for 14 years) have increased aboveground growth but have not affected canopy leaf biomass or leaf area index. In order to understand the mechanism behind the increases in growth, we hypothesized that the NO3(-) additions increased foliar N concentrations and leaf-level photosynthesis in the dominant species in these forests (sugar maple, Acer saccharum). The NO3(-) additions significantly increased foliar N. However, there was no significant difference between the ambient and +NO3(-) treatments in two seasons (2006-2007) of instantaneous measurements of photosynthesis from either canopy towers or excised branches. In measurements on excised branches, photosynthetic nitrogen use efficiency (micromol CO2 s(-1) g(-1) N) was significantly decreased (-13%) by NO3(-) additions. Furthermore, we found no consistent NO3(-) effect across all sites in either current foliage or leaf litter collected annually throughout the study (1993-2007) and analyzed for delta 13C and delta 18O, isotopes that can be used together to integrate changes in photosynthesis over time. We observed a small but significant NO3(-) effect on the average area and mass of individual leaves from the excised branches, but these differences varied by site and were countered by changes in leaf number. These photosynthesis and leaf area data together suggest that NO3(-) additions have not stimulated photosynthesis. There is no evidence that nutrient deficiencies have developed at

  8. Increasing importance of deposition of reduced nitrogen in the United States.

    Science.gov (United States)

    Li, Yi; Schichtel, Bret A; Walker, John T; Schwede, Donna B; Chen, Xi; Lehmann, Christopher M B; Puchalski, Melissa A; Gay, David A; Collett, Jeffrey L

    2016-05-24

    Rapid development of agriculture and fossil fuel combustion greatly increased US reactive nitrogen emissions to the atmosphere in the second half of the 20th century, resulting in excess nitrogen deposition to natural ecosystems. Recent efforts to lower nitrogen oxides emissions have substantially decreased nitrate wet deposition. Levels of wet ammonium deposition, by contrast, have increased in many regions. Together these changes have altered the balance between oxidized and reduced nitrogen deposition. Across most of the United States, wet deposition has transitioned from being nitrate-dominated in the 1980s to ammonium-dominated in recent years. Ammonia has historically not been routinely measured because there are no specific regulatory requirements for its measurement. Recent expansion in ammonia observations, however, along with ongoing measurements of nitric acid and fine particle ammonium and nitrate, permit new insight into the balance of oxidized and reduced nitrogen in the total (wet + dry) US nitrogen deposition budget. Observations from 37 sites reveal that reduced nitrogen contributes, on average, ∼65% of the total inorganic nitrogen deposition budget. Dry deposition of ammonia plays an especially key role in nitrogen deposition, contributing from 19% to 65% in different regions. Future progress toward reducing US nitrogen deposition will be increasingly difficult without a reduction in ammonia emissions.

  9. Increased forest carbon storage with increased atmospheric CO2 despite nitrogen limitation: a game-theoretic allocation model for trees in competition for nitrogen and light.

    Science.gov (United States)

    Dybzinski, Ray; Farrior, Caroline E; Pacala, Stephen W

    2015-03-01

    Changes in resource availability often cause competitively driven changes in tree allocation to foliage, wood, and fine roots, either via plastic changes within individuals or through turnover of individuals with differing strategies. Here, we investigate how optimally competitive tree allocation should change in response to elevated atmospheric CO2 along a gradient of nitrogen and light availability, together with how those changes should affect carbon storage in living biomass. We present a physiologically-based forest model that includes the primary functions of wood and nitrogen. From a tree's perspective, wood is an offensive and defensive weapon used against neighbors in competition for light. From a biogeochemical perspective, wood is the primary living reservoir of stored carbon. Nitrogen constitutes a tree's photosynthetic machinery and the support systems for that machinery, and its limited availability thus reduces a tree's ability to fix carbon. This model has been previously successful in predicting allocation to foliage, wood, and fine roots along natural productivity gradients. Using game theory, we solve the model for competitively optimal foliage, wood, and fine root allocation strategies for trees in competition for nitrogen and light as a function of CO2 and nitrogen mineralization rate. Instead of down-regulating under nitrogen limitation, carbon storage under elevated CO2 relative to carbon storage at ambient CO2 is approximately independent of the nitrogen mineralization rate. This surprising prediction is a consequence of both increased competition for nitrogen driving increased fine root biomass and increased competition for light driving increased allocation to wood under elevated CO2 .

  10. Nitrogen balance during compensatory growth when changing the levels of dietary lysine from deficiency to sufficiency in growing pigs.

    Science.gov (United States)

    Ishida, Aiko; Kyoya, Takahito; Nakashima, Kazuki; Katsumata, Masaya

    2012-11-01

    Two experiments were conducted to elucidate the nitrogen (N) balance of pigs exhibiting compensatory growth when changing the dietary lysine levels from deficiency to sufficiency. Experiment 1 elucidated whether pigs exhibited compensatory growth with dietary lysine sufficiency. Twenty 6-week-old males were assigned to one of two treatments: control and LC (lysine and control). Control pigs were fed a control diet throughout the 24-day experimental period, whereas LC pigs were fed a low lysine diet until day 21 of the experiment, followed by the control diet until the end of experiment. The dietary lysine sufficiency treatment induced an 80% increase in the growth rate of LC pigs (P pigs that exhibited compensatory growth with dietary lysine sufficiency. Eighteen 6-week-old males were assigned to one of three treatments: control, LC, and LL (low lysine). LL pigs were fed a low lysine diet throughout the 24-day experimental period. Pigs that exhibited compensatory growth with dietary lysine sufficiency tended to retain a higher amount of N than control pigs (P = 0.10). These finding suggest that the compensatory growth induced in pigs by dietary lysine sufficiency was partly attributable to a higher level of N retention.

  11. Parental vitamin D deficiency during pregnancy is associated with increased blood pressure in offspring via Panx1 hypermethylation

    NARCIS (Netherlands)

    Meems, Laura M. G.; Mahmud, Hasan; Buikema, Hendrik; Tost, Jorg; Michel, Sven; Takens, Janny; Verkaik-Schakel, Rikst N; Vreeswijk-Baudoin, Inge; Mateo-Leach, Irene V.; van der Harst, Pim; Plosch, Torsten; de Boer, Rudolf A.

    2016-01-01

    Vitamin D deficiency is one of the most common nutritional deficiencies worldwide. Maternal vitamin D deficiency is associated with increased susceptibility to hypertension in offspring, but the reasons for this remain unknown. The aim of this study was to determine if parental vitamin D deficiency

  12. Parental vitamin D deficiency during pregnancy is associated with increased blood pressure in offspring via Panx1 hypermethylation

    NARCIS (Netherlands)

    Meems, Laura M. G.; Mahmud, Hasan; Buikema, Hendrik; Tost, Jorg; Michel, Sven; Takens, Janny; Verkaik-Schakel, Rikst N; Vreeswijk-Baudoin, Inge; Mateo-Leach, Irene V.; van der Harst, Pim; Plosch, Torsten; de Boer, Rudolf A.

    2016-01-01

    Vitamin D deficiency is one of the most common nutritional deficiencies worldwide. Maternal vitamin D deficiency is associated with increased susceptibility to hypertension in offspring, but the reasons for this remain unknown. The aim of this study was to determine if parental vitamin D deficiency

  13. Support for a Photoprotective Function of Winter Leaf Reddening in Nitrogen-Deficient Individuals of Lonicera japonica

    Directory of Open Access Journals (Sweden)

    Kaylyn L. Carpenter

    2014-11-01

    Full Text Available Plants growing in high-light environments during winter often exhibit leaf reddening due to synthesis of anthocyanin pigments, which are thought to alleviate photooxidative stress associated with low-temperature photoinhibition through light attenuation and/or antioxidant activity. Seasonal high-light stress can be further exacerbated by a limited photosynthetic capacity, such as nitrogen-deficiency. In the present study, we test the following hypotheses using three populations of the semi-evergreen vine Lonicera japonica: (1 nitrogen deficiency corresponds with reduced photosynthetic capacity; (2 individuals with reduced photosynthetic capacity synthesize anthocyanin pigments in leaves during winter; and (3 anthocyanin pigments help alleviate high-light stress by attenuating green light. All populations featured co-occurring winter-green and winter-red leafed individuals on fully-exposed (high-light, south-facing slopes in the Piedmont of North Carolina, USA. Consistent with our hypotheses, red leaves consistently exhibited significantly lower foliar nitrogen than green leaves, as well as lower total chlorophyll, quantum yield efficiency, carboxylation efficiency, and photosynthesis at saturating irradiance (Asat. Light-response curves measured using ambient sunlight versus red-blue LED (i.e., lacking green wavelengths demonstrated significantly reduced quantum yield efficiency and a higher light compensation point under sunlight relative to red-blue LED in red leaves, but not in green leaves, consistent with a (green light-attenuating function of anthocyanin pigments. These results are consistent with the hypothesis that intraspecific anthocyanin synthesis corresponds with nitrogen deficiency and reduced photosynthetic capacity within populations, and support a light-attenuating function of anthocyanin pigments.

  14. Nonprotein nitrogen is absorbed from the large intestine and increases nitrogen balance in growing pigs fed a valine-limiting diet.

    Science.gov (United States)

    Columbus, Daniel A; Lapierre, Hélène; Htoo, John K; de Lange, Cornelis F M

    2014-05-01

    Nitrogen absorption from the large intestine, largely as ammonia and possibly as amino acids (AAs), is generally thought to be of little nutritional value to nonruminant animals and humans. Ammonia-nitrogen absorbed from the large intestine, however, may be recycled into the small intestine as urea and incorporated into microbial AAs, which may then be used by the host. A cecal infusion study was performed to determine the form in which nitrogen is absorbed from the large intestine and the impact of large intestine nitrogen supply on nitrogen balance in growing pigs. Eighteen cecally cannulated barrows (initial body weight: 22.4 ± 1.2 kg) were used to determine the effect of supplying nitrogen into the large intestine from either casein or urea on whole-body nitrogen retention and urea kinetics. Treatments were cecal infusions of saline (control), casein, or urea with nitrogen infused at a rate of 40% of nitrogen intake. In a subsample of 9 pigs, (15)N(15)N-urea was infused via i.v. during the nitrogen-balance period to determine urea kinetics. All pigs were fed a valine-limiting cornstarch-soybean meal-based diet. More than 80% of infused nitrogen was apparently absorbed. Urea flux and urinary nitrogen excretion increased (P ≤ 0.05) by the same amount for both nitrogen sources, but this increase did not fully account for the increase in nitrogen absorption from the large intestine. Whole-body nitrogen retention improved with nitrogen infusions (129 vs. 114 g/d; P 0.05) between nitrogen sources. Absorption of nitrogen from the large intestine appears to be in the form of nonprotein nitrogen, which appears to be returned to the small intestine via urea and used there for microbial AA production and should therefore be considered when determining nitrogen and AA supply and requirements.

  15. Ageing Fxr deficient mice develop increased energy expenditure, improved glucose control and liver damage resembling NASH.

    Directory of Open Access Journals (Sweden)

    Mikael Bjursell

    Full Text Available Nuclear receptor subfamily 1, group H, member 4 (Nr1h4, FXR is a bile acid activated nuclear receptor mainly expressed in the liver, intestine, kidney and adrenal glands. Upon activation, the primary function is to suppress cholesterol 7 alpha-hydroxylase (Cyp7a1, the rate-limiting enzyme in the classic or neutral bile acid synthesis pathway. In the present study, a novel Fxr deficient mouse line was created and studied with respect to metabolism and liver function in ageing mice fed chow diet. The Fxr deficient mice were similar to wild type mice in terms of body weight, body composition, energy intake and expenditure as well as behaviours at a young age. However, from 15 weeks of age and onwards, the Fxr deficient mice had almost no body weight increase up to 39 weeks of age mainly because of lower body fat mass. The lower body weight gain was associated with increased energy expenditure that was not compensated by increased food intake. Fasting levels of glucose and insulin were lower and glucose tolerance was improved in old and lean Fxr deficient mice. However, the Fxr deficient mice displayed significantly increased liver weight, steatosis, hepatocyte ballooning degeneration and lobular inflammation together with elevated plasma levels of ALT, bilirubin and bile acids, findings compatible with non-alcoholic steatohepatitis (NASH and cholestasis. In conclusion, ageing Fxr deficient mice display late onset leanness associated with elevated energy expenditure and improved glucose control but develop severe NASH-like liver pathology.

  16. Dissolved organic nitrogen dominates in European bogs under increasing atmospheric N deposition

    NARCIS (Netherlands)

    Bragazza, L.; Limpens, J.

    2004-01-01

    To assess the effects of increased atmospheric N input on N availability in ombrotrophic peatlands, the relative concentrations of dissolved organic nitrogen (DON) to dissolved inorganic nitrogen (DIN) were measured in bog waters along a natural gradient of atmospheric N deposition. Six European bog

  17. Exploring nutrient management options to increase nitrogen and phosphorus use efficiencies in food production of China

    NARCIS (Netherlands)

    Wang, Mengru; Ma, Lin; Strokal, Maryna; Chu, Yanan; Kroeze, Carolien

    2017-01-01

    Low nitrogen (NUE) and phosphorus (PUE) use efficiencies in food production in China result in large losses of nitrogen (N) and phosphorus (P) to the environment. The Chinese government formulated policies to increase the NUEs and PUEs. Recent policies aim for zero growth in synthetic fertilizer

  18. Vitamin B(12) deficiency stimulates osteoclastogenesis via increased homocysteine and methylmalonic acid.

    Science.gov (United States)

    Vaes, Bart L T; Lute, Carolien; Blom, Henk J; Bravenboer, Nathalie; de Vries, Teun J; Everts, Vincent; Dhonukshe-Rutten, Rosalie A; Müller, Michael; de Groot, Lisette C P G M; Steegenga, Wilma T

    2009-05-01

    The risk of nutrient deficiencies increases with age in our modern Western society, and vitamin B(12) deficiency is especially prevalent in the elderly and causes increased homocysteine (Hcy) and methylmalonic acid (MMA) levels. These three factors have been recognized as risk factors for reduced bone mineral density and increased fracture risk, though mechanistic evidence is still lacking. In the present study, we investigated the influence of B(12), Hcy, and MMA on differentiation and activity of bone cells. B(12) deficiency did not affect the onset of osteoblast differentiation, maturation, matrix mineralization, or adipocyte differentiation from human mesenchymal stem cells (hMSCs). B(12) deficiency caused an increase in the secretion of Hcy and MMA into the culture medium by osteoblasts, but Hcy and MMA appeared to have no effect on hMSC osteoblast differentiation. We further studied the effect of B(12), Hcy, and MMA on the formation of multinucleated tartrate-resistant acid phosphatase-positive osteoclasts from mouse bone marrow. We observed that B(12) did not show an effect on osteoclastogenesis. However, Hcy as well as MMA were found to induce osteoclastogenesis in a dose-dependent manner. On the basis of these results, we conclude that B(12) deficiency may lead to decreased bone mass by increased osteoclast formation due to increased MMA and Hcy levels.

  19. Increasing foliar Zn:Ni or Cu:Ni concentration ratios increase severity of nickel deficiency symptoms

    Science.gov (United States)

    The occurrence of nickel (Ni) deficiency of pecan [Carya illinoinensis (Wangenh.) K. Koch] in orchards is an increasingly common problem. There is uncertainty regarding the primary cause of the problem, as orchard soils have plenty of Ni. The influence of essential micronutrients on the endogenous...

  20. Increased gastric IL-1β concentration and iron deficiency parameters in H. pylori infected children.

    Science.gov (United States)

    Queiroz, Dulciene Maria Magalhaes; Rocha, Andreia Maria Camargos; Melo, Fabricio Freire; Rocha, Gifone Aguiar; Teixeira, Kádima Nayara; Carvalho, Simone Diniz; Bittencourt, Paulo Fernando Souto; Castro, Lucia Porto Fonseca; Crabtree, Jean E

    2013-01-01

    Association between H. pylori infection, iron deficiency and iron deficiency anaemia has been described, but the mechanisms involved have not been established. We hypothesized that in H. pylori infected children increased gastric concentrations of IL-1β and/or TNF-α, both potent inhibitors of gastric acid secretion that is essential for iron absorption, are predictors for low blood concentrations of ferritin and haemoglobin, markers of early depletion of iron stores and anaemia, respectively. We evaluated 125 children undergoing endoscopy to clarify the origin of gastrointestinal symptoms. Gastric specimens were obtained for H. pylori status and cytokine evaluation and blood samples for determination of iron deficiency/iron deficiency anaemia parameters and IL1 cluster and TNFA polymorphisms that are associated with increased cytokine secretions. Higher IL-1β and TNF-α gastric concentrations were observed in H. pylori-positive (n = 47) than in -negative (n = 78) children. Multiple linear regression models revealed gastric IL-1β, but not TNF-α, as a significant predictor of low ferritin and haemoglobin concentrations; results were reproduced in young children in whom IL1RN polymorphic genotypes associated with higher gastric IL-1β expression and lower blood ferritin and haemoglobin concentrations. In conclusion, high gastric levels of IL-1β can be the link between H. pylori infection and iron deficiency/iron deficiency anaemia in childhood.

  1. Nitrogen deficiency as well as phosphorus deficiency in sorghum promotes the production and exudation of 5-deoxystrigol, the host recognition signal for arbuscular mycorrhizal fungi and root parasites.

    Science.gov (United States)

    Yoneyama, Kaori; Xie, Xiaonan; Kusumoto, Dai; Sekimoto, Hitoshi; Sugimoto, Yukihiro; Takeuchi, Yasutomo; Yoneyama, Koichi

    2007-12-01

    Strigolactones released from plant roots induce hyphal branching of symbiotic arbuscular mycorrhizal (AM) fungi and germination of root parasitic weeds, Striga and Orobanche spp. We already demonstrated that, in red clover plants (Trifolium pratense L.), a host for both AM fungi and the root holoparasitic plant Orobanche minor Sm., reduced supply of phosphorus (P) but not of other elements examined (N, K, Ca, Mg) in the culture medium significantly promoted the secretion of a strigolactone, orobanchol, by the roots of this plant. Here we show that in the case of sorghum [Sorghum bicolor (L.) Moench], a host of both the root hemiparasitic plant Striga hermonthica and AM fungi, N deficiency as well as P deficiency markedly enhanced the secretion of a strigolactone, 5-deoxystrigol. The 5-deoxystrigol content in sorghum root tissues also increased under both N deficiency and P deficiency, comparable to the increase in the root exudates. These results suggest that strigolactones may be rapidly released after their production in the roots. Unlike the situation in the roots, neither N nor P deficiency affected the low content of 5-deoxystrigol in sorghum shoot tissues.

  2. Oxidative Stress and Antioxidant Responses in Young Leaves of Mulberry Plants Grown Under Nitrogen,Phosphorus or Potassium Deficiency

    Institute of Scientific and Technical Information of China (English)

    Rajesh Kumar Tewari; Praveen Kumar; Parma Nand Sharma

    2007-01-01

    The aim of this study was to associate the generation of reactive oxygen species (ROS) with induced antioxidant responses and disturbed cellular redox environment in the nltrogen-(N), phosphorus-(P), or potassium-(K) deficient mulberry (Morus alba L. var. Kanva-2) plants. The indicators of oxidative stress and cellular redox environment and antioxidant defense-related parameters were analyzed. Deficiency of N, P or K suppressed growth,accelerated senescence, and decreased concentrations of chloroplastic pigments and glutathione. Lipid peroxidation and activities of superoxide dismutase, ascorbate peroxidase and glutathione reductase were also increased in these N, P, or K deprived plants. Concentration of hydrogen peroxide increased in plants deficient in N or P. Deftciency of N or P particularly altered the cellular redox environment as indicated by changes in the redox couples,namely ascorblc acid/total ascorbate decreased in P-, glutathione sulfydryl/total glutathione decreased in N-, and increased in P-deficient plants. Activity staining of native gels for superoxide dismutase revealed increased activity as indicated by increased intensity of bands, and induction of few new isoforms in P- and K-deficient plants.Differences in the patterns of superoxide dismutase isoforms and redox status (ascorbic acid/total ascorbate and glutathlone sulfydryl/total glutathione) indicate that N-, P-, or K-deficiency altered antioxidant responses to varying extents in mulberry plants.

  3. Nitrogen

    Science.gov (United States)

    Apodaca, Lori E.

    2013-01-01

    The article presents an overview of the nitrogen chemical market as of July 2013, including the production of ammonia compounds. Industrial uses for ammonia include fertilizers, explosives, and plastics. Other topics include industrial capacity of U.S. ammonia producers CF Industries Holdings Inc., Koch Nitrogen Co., PCS Nitrogen, Inc., and Agrium Inc., the impact of natural gas prices on the nitrogen industry, and demand for corn crops for ethanol production.

  4. Strategies to increase nitrogen use efficiency and reduce nitrate leaching in vegetable production in the Netherlands

    NARCIS (Netherlands)

    Ruijter, de F.J.; Berge, ten H.F.M.; Smit, A.L.

    2010-01-01

    Environmental concern and legislation of fertilization requires strategies to increase nitrogen use efficiency and reduce nitrate leaching. Strategies can be fertilizer choice, timing of N availability and fertilizer placement. Rainfall in the experimental year 2007 was moderate and different strate

  5. Multiple nitrogen and phosphorus deficiency in Zantedeschia Deficiência múltipla de nitrogênio e fósforo em copo-de-leite

    Directory of Open Access Journals (Sweden)

    Katiúcia Dias Fernandes

    2012-12-01

    Full Text Available Multiple nutritional deficiencies are considered one of several factors that can induce doubt in the diagnosis based only in visual symptoms, because it makes identification more difficult. The aim of this work was to evaluate the development of Zantedeschia and the morphological changes resulting from nutritional disorders caused by multiple and simple nitrogen and phosphorus deficiency in plants grown in nutrient solution. Zantedeschia plants were grown for a period of eight months in a complete Hoagland and Arnon (1950 solution, with nitrogen (-N omission, with phosphorus (-P omission, with nitrogen and phosphorus (-NP omission, and also nutrient solution with N and P at concentrations of 25, 50 and 75%, totalizing 7 treatments, with 4 replicates in a completely randomized experimental design. At the end of the experimental period, plant height, number of emitted leaves, leaf size, number and mineral composition of shoots were assessed. The omission of nutrients both in simple and multiple forms affected plant development. The highest shoot formation occurred in plants grown in solution and with 50% of the concentration of NP. The mineral composition of macronutrients present in leaves and shoots of plants was influenced by multiple deficiencies of N and P.A deficiência múltipla é considerada um dos vários fatores que pode induzir dúvidas na diagnose baseada apenas na sintomatologia, pois torna a identificação mais difícil. Assim, objetivou-se avaliar o desenvolvimento de copo-de-leite (Zantedeschia aethiopica e as alterações morfológicas decorrentes da desordem nutricional provocada pela omissão múltipla e isolada de nitrogênio e fósforo em plantas cultivadas em solução nutritiva. O copo-de-leite foi cultivado por um período de 8 meses em solução de Hoagland e Arnon (1950 completa e com omissão simples de nitrogênio (N, de fósforo (P e múltipla de NP e, ainda, solução nutritiva com NP nas concentrações, na propor

  6. Mice deficient in transmembrane prostatic acid phosphatase display increased GABAergic transmission and neurological alterations.

    Directory of Open Access Journals (Sweden)

    Heidi O Nousiainen

    Full Text Available Prostatic acid phosphatase (PAP, the first diagnostic marker and present therapeutic target for prostate cancer, modulates nociception at the dorsal root ganglia (DRG, but its function in the central nervous system has remained unknown. We studied expression and function of TMPAP (the transmembrane isoform of PAP in the brain by utilizing mice deficient in TMPAP (PAP-/- mice. Here we report that TMPAP is expressed in a subpopulation of cerebral GABAergic neurons, and mice deficient in TMPAP show multiple behavioral and neurochemical features linked to hyperdopaminergic dysregulation and altered GABAergic transmission. In addition to increased anxiety, disturbed prepulse inhibition, increased synthesis of striatal dopamine, and augmented response to amphetamine, PAP-deficient mice have enlarged lateral ventricles, reduced diazepam-induced loss of righting reflex, and increased GABAergic tone in the hippocampus. TMPAP in the mouse brain is localized presynaptically, and colocalized with SNARE-associated protein snapin, a protein involved in synaptic vesicle docking and fusion, and PAP-deficient mice display altered subcellular distribution of snapin. We have previously shown TMPAP to reside in prostatic exosomes and we propose that TMPAP is involved in the control of GABAergic tone in the brain also through exocytosis, and that PAP deficiency produces a distinct neurological phenotype.

  7. Pathways for the effects of increased nitrogen deposition on fauna

    NARCIS (Netherlands)

    Nijssen, M.E.; Wallis de Vries, M.F.; Siepel, H.

    2017-01-01

    Effects of increased N deposition, caused by agricultural practices and combustion of fossil fuels in traffic and industry, have been studied in detail for soil and water chemistry as well as for vegetation and ecosystem functioning. Knowledge on fauna is limited to descriptive and correlative data

  8. Transcriptomic Analysis of Sinorhizobium meliloti and Medicago truncatula Symbiosis Using Nitrogen Fixation-Deficient Nodules.

    Science.gov (United States)

    Lang, Claus; Long, Sharon R

    2015-08-01

    The bacterium Sinorhizobium meliloti interacts symbiotically with legume plant hosts such as Medicago truncatula to form nitrogen-fixing root nodules. During symbiosis, plant and bacterial cells differentiate in a coordinated manner, resulting in specialized plant cells that contain nitrogen-fixing bacteroids. Both plant and bacterial genes are required at each developmental stage of symbiosis. We analyzed gene expression in nodules formed by wild-type bacteria on six plant mutants with defects in nitrogen fixation. We observed differential expression of 482 S. meliloti genes with functions in cell envelope homeostasis, cell division, stress response, energy metabolism, and nitrogen fixation. We simultaneously analyzed gene expression in M. truncatula and observed differential regulation of host processes that may trigger bacteroid differentiation and control bacterial infection. Our analyses of developmentally arrested plant mutants indicate that plants use distinct means to control bacterial infection during early and late symbiotic stages.

  9. Increased resistance to fatigue in creatine kinase deficient muscle is not due to improved contractile economy.

    Science.gov (United States)

    ter Veld, Frank; Nicolay, Klaas; Jeneson, Jeroen A L

    2006-06-01

    There has been speculation on the origin of the increased endurance of skeletal muscles in creatine kinase (CK)-deficient mice. Important factors that have been raised include the documented increased mitochondrial capacity and alterations in myosin heavy chain (MyHC) isoform composition in CK-deficient muscle. More recently, the absence of inorganic phosphate release from phosphocreatine hydrolysis in exercising CK-deficient muscle has been postulated to contribute to the lower fatigueability in skeletal muscle. In this study, we tested the hypothesis that the reported shift in MyHC composition to slower isoforms in CK-deficient muscle leads to a decrease in oxygen cost of twitch performance. To that aim, extensor digitorum longus (EDL) and soleus (SOL) muscles were isolated from wild-type (WT) and knock-out mice deficient in the cytoplasmic muscle-type and sarcomeric mitochondrial isoenzymes of CK, and oxygen consumption per twitch time-tension-integral (TTI) was measured. The results show that the adaptive response to loss of CK function does not involve any major change to contractile economy of skeletal muscle.

  10. Does nitrogen deposition increase forest production? The role of phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Sabine, E-mail: sabine.braun@iap.c [Institute for Applied Plant Biology, CH-4124 Schoenenbuch (Switzerland); Thomas, Vera F.D.; Quiring, Rebecca; Flueckiger, Walter [Institute for Applied Plant Biology, CH-4124 Schoenenbuch (Switzerland)

    2010-06-15

    Effects of elevated N deposition on forest aboveground biomass were evaluated using long-term data from N addition experiments and from forest observation plots in Switzerland. N addition experiments with saplings were established both on calcareous and on acidic soils, in 3 plots with Fagus sylvatica and in 4 plots with Picea abies. The treatments were conducted during 15 years and consisted of additions of dry NH{sub 4}NO{sub 3} at rates of 0, 10, 20, 40, 80, and 160 kg N ha{sup -1} yr{sup -1}. The same tree species were observed in permanent forest observation plots covering the time span between 1984 and 2007, at modeled N deposition rates of 12-46 kg N ha{sup -1} yr{sup -1}. Experimental N addition resulted in either no change or in a decreased shoot growth and in a reduced phosphorus concentration in the foliage in all experimental plots. In the forest, a decrease of foliar P concentration was observed between 1984 and 2007, resulting in insufficient concentrations in 71% and 67% of the Fagus and Picea plots, respectively, and in an increasing N:P ratio in Fagus. Stem increment decreased during the observation period even if corrected for age. Forest observations suggest an increasing P limitation in Swiss forests especially in Fagus which is accompanied by a growth decrease whereas the N addition experiments support the hypothesis that elevated N deposition is an important cause for this development. - Low P levels limit growth in Swiss forests.

  11. Influence of increasing doses nitrogen on physical and productive characteristics winter barley cultivar kristal

    Directory of Open Access Journals (Sweden)

    Stanković Saša

    2000-01-01

    Full Text Available Aiming at the investigation of the influence of mineral fertilizers on some physical, physiological and productive characteristics of the barley cv. Kristal, it has been investigated the influence of the increasing doses of nitrogen (0.100,120,140 kg/ha, while the content of P2 O5 and K2O was constant, that is, P2 O5-60 kg/ha, K2 O - 40 kg/ha. The germination energy and germinating ability greatly depend on mineral nourishment and are rather significantly great in relation to the control variant. The germination energy and germinating ability are greatest, 91.4 % and 94.5 %, at fertilizing with 100 kg/ha of nitrogen, while the least are 74.3 % and 75 % in the variant without fertilizing. There are no significant differences in the germination energy and germinating ability among the variants of fertilization. The content of proteins is the greatest in the variants with 120 kg/ha of nitrogen, amounting 15.20 %, while the least is in the non-fertilized variant, amounting 14 %. AU variants of fertilization show rather significantly great content of proteins in relation to the control one. The increased content of proteins in barley in the third and fourth variant in relation to the second one for 8 % and 2 %, points to the fact that increasing the aspect of the needs of brewing beer industry. The greatest yield of 5 400 kg/ha has been achieved at fertilizing with 140 kg/ha of nitrogen. The increased amount of nitrogen for 40%, and the decreased yield for 5 % at increasing nitrogen for 20 % in relation to the variant of fertilization with 100 kg/ha of nitrogen, points to the fact that the fertilization beyond the optimal doses of nitrogen is not economically justified. .

  12. Apolipoprotein-E-deficient mice exhibit an increased susceptibility to disseminated candidiasis.

    NARCIS (Netherlands)

    Vonk, A.G.; Bont, N. de; Netea, M.G.; Demacker, P.N.M.; Meer, J.W.M. van der; Stalenhoef, A.F.H.; Kullberg, B.J.

    2004-01-01

    The effect of hyperlipoproteinemia on systemic candidiasis was investigated by assessing the susceptibility of hyperlipoproteinemic, apolipoprotein E (ApoE)-deficient (ApoE -/-) mice to a systemic Candida albicans infection. The absence of ApoE in these mice resulted in an eightfold increase in

  13. Does Obesity Increase Risk for Iron Deficiency? A Review of the Literature and the Potential Mechanisms

    NARCIS (Netherlands)

    Cepeda-Lopez, A.C.; Aeberli, I.; Zimmermann, M.B.

    2010-01-01

    Increasing obesity is a major global health concern while at the same time iron-deficiency anemia remains common worldwide. Although these two conditions represent opposite ends of the spectrum of over- and under-nutrition, they appear to be linked: overweight individuals are at higher risk of iron

  14. Does Obesity Increase Risk for Iron Deficiency? A Review of the Literature and the Potential Mechanisms

    NARCIS (Netherlands)

    Cepeda-Lopez, A.C.; Aeberli, I.; Zimmermann, M.B.

    2010-01-01

    Increasing obesity is a major global health concern while at the same time iron-deficiency anemia remains common worldwide. Although these two conditions represent opposite ends of the spectrum of over- and under-nutrition, they appear to be linked: overweight individuals are at higher risk of iron

  15. Beer improves copper metabolism and increases longevity in Cu-deficient rats

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.J.; Klevay, L.M. (Dept. of Agriculture, Grand Forks, ND (USA))

    1989-02-09

    Moderate consumption of alcoholic beverages decreases risk of death from ischemic heart disease (IHD). Evidence suggests that Cu-deficiency is important in the etiology and pathophysiology of IHD. The effect of beer (25 ng Cu/ml) drinking on the severity of Cu-deficiency was examined in weanling, male Sprague-Dawley rats fed a low Cu diet (0.84 {mu}g Cu/g). Beer drinking increased median longevity to 204 or 299 d from 62 or 42 d respectively in rats drinking water in two experiments (15 rats/group). In experiment 3, a single dose of {sup 67}Cu (3.3 {mu}Ci as chloride) was added to 1 g of feed and given to 12-h fasted rats 30 d after the start of the experiment. Whole body counting over 13 d showed apparent Cu absorption and t{sub {1/2}} (biological) were greater in Cu-deficient rats drinking beer than in similar rats drinking water. Plasma cholesterol was lower but hematocrit and liver Cu were higher in surviving rats drinking beer than in rats drinking water. Body weight was not affected by beer in any experiment. In experiment 4, a 4% aqueous ethanol solution had no effect on longevity of copper deficient rats. A non-alcohol component of beer alters Cu metabolism and mitigates the severity of nutritional Cu-deficiency in rats.

  16. TIMP-1 gene deficiency increases tumour cell sensitivity to chemotherapy-induced apoptosis

    DEFF Research Database (Denmark)

    Davidsen, Marie Louise; Würts, S.Ø.; Rømer, Maria Unni Koefoed;

    2006-01-01

    in cancer. In this regard, several studies have demonstrated an antiapoptotic effect of TIMP-1 in a number of different cell types. Since chemotherapy works by inducing apoptosis in cancer cells, we raised the hypothesis that TIMP-1 promotes resistance against chemotherapeutic drugs. In order to investigate...... this hypothesis, we have established TIMP-1 gene-deficient and TIMP-1 wild-type fibrosarcoma cells from mouse lung tissue. We have characterised these cells with regard to TIMP-1 genotype, TIMP-1 expression, malignant transformation and sensitivity to chemotherapy-induced apoptosis. We show that TIMP-1 gene...... deficiency increases the response to chemotherapy considerably, confirming that TIMP-1 protects the cells from apoptosis. This is to our knowledge the first study investigating TIMP-1 and chemotherapy-induced apoptosis employing a powerful model system comprising TIMP-1 gene-deficient cells...

  17. Antagonist muscle moment is increased in ACL deficient subjects during maximal dynamic knee extension

    DEFF Research Database (Denmark)

    Alkjær, Tine; Simonsen, Erik B; Magnusson, S Peter

    2012-01-01

    INTRODUCTION: Coactivation of the hamstring muscles during dynamic knee extension may compensate for increased knee joint laxity in anterior cruciate ligament (ACL) deficient subjects. This study examined if antagonist muscle coactivation during maximal dynamic knee extension was elevated...... in subjects with anterior cruciate ligament (ACL) deficiency compared to age-matched healthy controls. METHODS: Electromyography (EMG) and net knee joint moments were recorded during maximal concentric quadriceps and eccentric hamstring contractions, performed in an isokinetic dynamometer (ROM: 90......-10°, angular speed: 30°/s). Hamstring antagonist EMG recorded during concentric quadriceps contraction was converted into antagonist moment based on the EMG-moment relationship observed during eccentric agonist contractions. RESULTS: The magnitude of antagonist hamstring EMG was 65.5% higher in ACL deficient...

  18. Brain 5-HT deficiency increases stress vulnerability and impairs antidepressant responses following psychosocial stress.

    Science.gov (United States)

    Sachs, Benjamin D; Ni, Jason R; Caron, Marc G

    2015-02-24

    Brain serotonin (5-HT) deficiency and exposure to psychosocial stress have both been implicated in the etiology of depression and anxiety disorders, but whether 5-HT deficiency influences susceptibility to depression- and anxiety-like phenotypes induced by psychosocial stress has not been formally established. Most clinically effective antidepressants increase the extracellular levels of 5-HT, and thus it has been hypothesized that antidepressant responses result from the reversal of endogenous 5-HT deficiency, but this hypothesis remains highly controversial. Here we evaluated the impact of brain 5-HT deficiency on stress susceptibility and antidepressant-like responses using tryptophan hydroxylase 2 knockin (Tph2KI) mice, which display 60-80% reductions in brain 5-HT. Our results demonstrate that 5-HT deficiency leads to increased susceptibility to social defeat stress (SDS), a model of psychosocial stress, and prevents the fluoxetine (FLX)-induced reversal of SDS-induced social avoidance, suggesting that 5-HT deficiency may impair antidepressant responses. In light of recent clinical and preclinical studies highlighting the potential of inhibiting the lateral habenula (LHb) to achieve antidepressant and antidepressant-like responses, we also examined whether LHb inhibition could achieve antidepressant-like responses in FLX-insensitive Tph2KI mice subjected to SDS. Our data reveal that using designer receptors exclusively activated by designer drugs (DREADDs) to inhibit LHb activity leads to reduced SDS-induced social avoidance behavior in both WT and Tph2KI mice. This observation provides additional preclinical evidence that inhibiting the LHb might represent a promising alternative therapeutic approach under conditions in which selective 5-HT reuptake inhibitors are ineffective.

  19. Detection of nitrogen deficiency QTL in juvenile wild barley introgression lines growing in a hydroponic system.

    Science.gov (United States)

    Hoffmann, Astrid; Maurer, Andreas; Pillen, Klaus

    2012-10-20

    In this report we studied the genetic regulation of juvenile development of wild barley introgression lines (S42ILs) under two contrasting hydroponic nitrogen (N) supplies. Ten shoot and root related traits were examined among 42 S42ILs and the recurrent parent 'Scarlett'. The traits included tiller number, leaf number, plant height, leaf and root length, leaf to root length ratio, shoots and root dry weight, shoot to root weight ratio, and chlorophyll content. Our aims were (1) to test the suitability of a hydroponic system for early detection of favourable S42ILs, (2) to locate quantitative trait loci (QTL) that control the examined traits, (3) to identify favourable wild barley alleles that improve trait performances in regard to N treatment and, finally, (4) to validate the identified QTL through comparison with previously reported QTL originating from the same parental cross. The phenotypic data were analysed in a mixed model association study to detect QTL. The post-hoc Dunnett test identified 28 S42ILs that revealed significant (P hydroponic N study corresponded to QTL that were also detected in field trials with adult plants of a similar S42IL set or of the original S42 population. For instance, S42IL-135, -136 and -137, revealed increasing Hsp effects for tiller number, leaf number, leaf length, plant height and leaf to root ratio on the long arm of chromosome 7H. These QTL correspond to QTL for ears per plant and plant height that were previously detected in field trials conducted with the same S42ILs or with the S42 population. Our results suggest that the QTL we identified under hydroponic N cultivation partly correspond to QTL detected in field experiments. Due to this finding, screening of plants in early developmental stages grown in a hydroponic system may be a fast and cost effective method for early QTL detection and marker-assisted allelic selection, potentially speeding up elite barley breeding programs.

  20. Prenatal Iron Deficiency in Guinea Pigs Increases Locomotor Activity but Does Not Influence Learning and Memory.

    Directory of Open Access Journals (Sweden)

    Catherine Fiset

    Full Text Available The objective of the current study was to determine whether prenatal iron deficiency induced during gestation in guinea pigs affected locomotor activity and learning and memory processes in the progeny. Dams were fed either iron-deficient anemic or iron-sufficient diets throughout gestation and lactation. After weaning, all pups were fed an iron-sufficient diet. On postnatal day 24 and 40, the pups' locomotor activity was observed within an open-field test, and from postnatal day 25 to 40, their learning and memory processes were assessed within a Morris Water Maze. The behavioural and cognitive tests revealed that the iron deficient pup group had increased locomotor activity, but solely on postnatal day 40, and that there were no group differences in the Morris Water Maze. In the general discussion, we propose that prenatal iron deficiency induces an increase in nervousness due to anxiety in the progeny, which, in the current study, resulted in an increase of locomotor activity.

  1. Carbon input increases microbial nitrogen demand, but not microbial nitrogen mining in boreal forest soils

    Science.gov (United States)

    Wild, Birgit; Alaei, Saeed; Bengtson, Per; Bodé, Samuel; Boeckx, Pascal; Schnecker, Jörg; Mayerhofer, Werner; Rütting, Tobias

    2016-04-01

    Plant primary production at mid and high latitudes is often limited by low soil N availability. It has been hypothesized that plants can indirectly increase soil N availability via root exudation, i.e., via the release of easily degradable organic compounds such as sugars into the soil. These compounds can stimulate microbial activity and extracellular enzyme synthesis, and thus promote soil organic matter (SOM) decomposition ("priming effect"). Even more, increased C availability in the rhizosphere might specifically stimulate the synthesis of enzymes targeting N-rich polymers such as proteins that store most of the soil N, but are too large for immediate uptake ("N mining"). This effect might be particularly important in boreal forests, where plants often maintain high primary production in spite of low soil N availability. We here tested the hypothesis that increased C availability promotes protein depolymerization, and thus soil N availability. In a laboratory incubation experiment, we added 13C-labeled glucose to a range of soil samples derived from boreal forests across Sweden, and monitored the release of CO2 by C mineralization, distinguishing between CO2 from the added glucose and from the native, unlabeled soil organic C (SOC). Using a set of 15N pool dilution assays, we further measured gross rates of protein depolymerization (the breakdown of proteins into amino acids) and N mineralization (the microbial release of excess N as ammonium). Comparing unamended control samples, we found a high variability in C and N mineralization rates, even when normalized by SOC content. Both C and N mineralization were significantly correlated to SOM C/N ratios, with high C mineralization at high C/N and high N mineralization at low C/N, suggesting that microorganisms adjusted C and N mineralization rates to the C/N ratio of their substrate and released C or N that was in excess. The addition of glucose significantly stimulated the mineralization of native SOC in soils

  2. Magnesium Deficiency Results in Increased Suberization in Endodermis and Hypodermis of Corn Roots 1

    Science.gov (United States)

    Pozuelo, José M.; Espelie, Karl E.; Kolattukudy, P. E.

    1984-01-01

    The composition of the aliphatic components of suberin in the stele and cortex of young corn (Zea mays L.) roots was determined by combined gas-liquid chromatography/mass spectrometry of the LiAlD4 depolymerization products. ω-Hydroxy acids were shown to be the major class of the aliphatic components of both the hypodermal (35%) and endodermal (28%) polymeric materials with the dominant chain length being C24 in the former and C16 in the latter. Nitrobenzene oxidation of the roots generated p-hydroxybenzaldehyde and vanillin with much less syringaldehyde. Electron microscopic examination of the hypodermal and endodermal cell walls from roots of corn plants grown in a Mg2+ -deficient (0.03 millimolar) nutrient solution showed that these walls were more heavily suberized than the analogous walls of roots from plants grown in normal (2 millimolar) Mg2+ levels. Analysis of the LiAlD4 depolymerization products of the suberin polymers from these roots showed that the roots grown in low Mg2+ had 3.5 times as much aliphatic suberin monomers on a weight basis as the roots from plants grown in nutrient with normal Mg2+ levels. Roots from plants grown in Mg2+ -deficient nutrient solution released 3.8 times the amount of aromatic aldehydes upon nitrobenzene oxidation as that released from normal roots. As the degree of Mg2+ deficiency of the nutrient solution was increased, there was an increase in the aliphatic and aromatic components characteristic of suberin. Thus, both ultrastructural and chemical evidence strongly suggested that Mg2+ deficiency resulted in increased suberization of the cell walls of both hypodermis and endodermis of Zea mays roots. The roots from Mg2+ -deficient plants also had a higher amount of peroxidase activity when compared to control roots. Images Fig. 1-3 PMID:16663407

  3. Serine protease inhibitor 6-deficient mice have increased neutrophil immunity to Pseudomonas aeruginosa.

    Science.gov (United States)

    Zhang, Manling; Liu, Ni; Park, Sun-Mi; Wang, Yue; Byrne, Susan; Murmann, Andrea E; Bahr, Scott; Peter, Marcus E; Olson, Steven T; Belaaouaj, Abderrazzaq; Ashton-Rickardt, Philip G

    2007-10-01

    Inflammation is a localized, protective response to trauma or microbial invasion that destroys the injurious agent and the injured tissue. Neutrophil elastase (NE), a serine protease stored in the azurophil granules of polymorphonuclear neutrophils, digests microbes after phagocytosis. NE can also digest microbes extracellularly but is associated with tissue damage and inflammatory disease. In this study, we show that polymorphonuclear neutrophils from mice deficient in serine protease inhibitor 6, a weak intracellular NE inhibitor, had increased susceptibility to self-inflicted lysis because of increased NE activity. The resulting transient increase in local extracellular NE activity was within a narrow range that resulted in the clearance of Pseudomonas aeruginosa but did not damage the lung. Therefore, deficiency in a weak intracellular inhibitor of NE results in an acute inflammatory response that protects from P. aeruginosa but does not cause lung disease.

  4. Nitric oxide signals ROS scavenger-mediated enhancement of PAL activity in nitrogen-deficient Matricaria chamomilla roots: side effects of scavengers.

    Science.gov (United States)

    Kovácik, Jozef; Klejdus, Borivoj; Backor, Martin

    2009-06-15

    Owing to the abundance of phenolic metabolites in plant tissue, their accumulation represents an important tool for stress protection. However, the regulation of phenolic metabolism is still poorly known. The regulatory role of reactive oxygen species (ROS) in the activity of phenylalanine ammonia-lyase (PAL) in nitrogen (N)-deficient chamomile roots treated for 24 h was studied using three ROS scavengers [dithiothreitol (DTT), salicylhydroxamic acid, and sodium benzoate]. Scavengers decreased the level of hydrogen peroxide and/or superoxide (and up-regulated ascorbate/guaiacol peroxidase and glutathione reductase), but, surprisingly, stimulated PAL activity. This up-regulation was correlated with increases in nitric oxide (NO) content, total soluble phenols, selected phenolic acids, and, partially, lignin (being expressed the most in DTT-exposed roots). We therefore tested the hypothesis that NO may be involved in these changes. Application of 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) decreased PAL activity and the accumulation of soluble phenols in all treatments. Exogenous H(2)O(2) and NO also stimulated PAL activity and the accumulation of phenols. We conclude that NO, in addition to hydrogen peroxide, may regulate PAL activity during N deficiency. The anomalous effect of PTIO on NO content and possible mechanism of ROS scavenger-evoked NO increases in light of the current knowledge are also discussed.

  5. Emerging and established technologies to increase nitrogen use efficiency of cereals

    Science.gov (United States)

    Nitrogen (N) fertilizers are expensive inputs; additionally, loss of N increases costs, contributes to soil acidification, and causes off-site pollution of air, groundwater and waterways. This study reviews current knowledge about technologies for N fertilization with potential to increase N use eff...

  6. Wfs1-deficient mice display altered function of serotonergic system and increased behavioural response to antidepressants

    Directory of Open Access Journals (Sweden)

    Tanel eVisnapuu

    2013-07-01

    Full Text Available It has been shown that mutations in the WFS1 gene make humans more susceptible to mood disorders. Besides that, mood disorders are associated with alterations in the activity of serotonergic and noradrenergic systems. Therefore, in this study, the effects of imipramine, an inhibitor of serotonin (5-HT and noradrenaline (NA reuptake, and paroxetine, a selective inhibitor of 5-HT reuptake, were studied in tests of behavioural despair. The tail suspension test (TST and forced swimming test (FST were performed in Wfs1-deficient mice. Simultaneously, gene expression and monoamine metabolism studies were conducted to evaluate changes in 5-HT- and NA-ergic systems of Wfs1-deficient mice. The basal immobility time of Wfs1-deficient mice in TST and FST did not differ from that of their wild-type littermates. However, a significant reduction of immobility time in response to lower doses of imipramine and paroxetine was observed in homozygous Wfs1-deficient mice, but not in their wild-type littermates. In gene expression studies, the levels of 5-HT transporter (SERT were significantly reduced in the pons of homozygous animals. Monoamine metabolism was assayed separately in the dorsal and ventral striatum of naive mice and mice exposed for 30 minutes tobrightly lit motility boxes. We found that this aversive challenge caused a significant increase in the levels of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA, a metabolite of 5-HT, in the ventral and dorsal striatum of wild-type mice, but not in their homozygous littermates. Taken together, the blunted 5-HT metabolism and reduced levels of SERT are a likely reason for the elevated sensitivity of these mice to the action of imipramine and paroxetine. These changes in the pharmacological and neurochemical phenotype of Wfs1-deficient mice may help to explain the increased susceptibility of Wolfram syndrome patients to depressive states.

  7. Vitamin D Deficiency Increases the Risk of Adverse Neonatal Outcomes in Gestational Diabetes

    Science.gov (United States)

    Weinert, Letícia Schwerz; Reichelt, Angela Jacob; Schmitt, Leonardo Rauber; Boff, Roberta; Oppermann, Maria Lucia Rocha; Camargo, Joiza Lins; Silveiro, Sandra Pinho

    2016-01-01

    Background Gestational diabetes mellitus (GDM) and vitamin D deficiency have been associated with increased risk of adverse perinatal outcomes but the consequences of both conditions simultaneously present in pregnancy have not yet been evaluated. Our objective was to study the influence of vitamin D deficiency in neonatal outcomes of pregnancies with GDM. Methods 184 pregnant women with GDM referred to specialized prenatal monitoring were included in this cohort and had blood sampled for 25-hydroxyvitamin D measurement. Vitamin D was measured by chemiluminescence and deficiency was defined as < 20 ng/mL. Participants were followed until puerperium and adverse neonatal outcomes were evaluated. Results Newborns of women with vitamin D deficiency had higher incidences of hospitalization in intensive care units (ICU) (32 vs 19%, P = 0.048), of hypoglycemia (any, 17.3 vs 7.1%, P = 0.039requiring ICU, 15.3 vs 3.6%, P = 0.008), and were more frequently small for gestational age (SGA) (17.3 vs 5.9%, P = 0.017). After adjustment, relative risk (RR) for hypoglycemia requiring ICU was 3.63 (95%CI 1.09–12.11) and for SGA was 4.32 (95%CI 1.75–10.66). The incidence of prematurity, jaundice and shoulder dystocia was no statistically different between groups. Conclusions In this cohort of pregnant women with GDM, vitamin D deficiency was associated with a major increase in the incidence of adverse neonatal outcomes such as SGA newborns and neonatal hypoglycemia. PMID:27764194

  8. Inhibition of activin receptor type IIB increases strength and lifespan in myotubularin-deficient mice.

    Science.gov (United States)

    Lawlor, Michael W; Read, Benjamin P; Edelstein, Rachel; Yang, Nicole; Pierson, Christopher R; Stein, Matthew J; Wermer-Colan, Ariana; Buj-Bello, Anna; Lachey, Jennifer L; Seehra, Jasbir S; Beggs, Alan H

    2011-02-01

    X-linked myotubular myopathy (XLMTM) is a congenital disorder caused by deficiency of the lipid phosphatase, myotubularin. Patients with XLMTM often have severe perinatal weakness that requires mechanical ventilation to prevent death from respiratory failure. Muscle biopsy specimens from patients with XLMTM exhibit small myofibers with central nuclei and central aggregations of organelles in many cells. It was postulated that therapeutically increasing muscle fiber size would cause symptomatic improvement in myotubularin deficiency. Recent studies have elucidated an important role for the activin-receptor type IIB (ActRIIB) in regulation of muscle growth and have demonstrated that ActRIIB inhibition results in significant muscle hypertrophy. To evaluate whether promoting muscle hypertrophy can attenuate symptoms resulting from myotubularin deficiency, the effect of ActRIIB-mFC treatment was determined in myotubularin-deficient (Mtm1δ4) mice. Compared with wild-type mice, untreated Mtm1δ4 mice have decreased body weight, skeletal muscle hypotrophy, and reduced survival. Treatment of Mtm1δ4 mice with ActRIIB-mFC produced a 17% extension of lifespan, with transient increases in weight, forelimb grip strength, and myofiber size. Pathologic analysis of Mtm1δ4 mice during treatment revealed that ActRIIB-mFC produced marked hypertrophy restricted to type 2b myofibers, which suggests that oxidative fibers in Mtm1δ4 animals are incapable of a hypertrophic response in this setting. These results support ActRIIB-mFC as an effective treatment for the weakness observed in myotubularin deficiency. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  9. Polμ deficiency increases resistance to oxidative damage and delays liver aging.

    Directory of Open Access Journals (Sweden)

    Beatriz Escudero

    Full Text Available Polμ is an error-prone PolX polymerase that contributes to classical NHEJ DNA repair. Mice lacking Polμ (Polμ(-/- show altered hematopoiesis homeostasis and DSB repair and a more pronounced nucleolytic resection of some V(DJ junctions. We previously showed that Polμ(-/- mice have increased learning capacity at old ages, suggesting delayed brain aging. Here we investigated the effect of Polμ(-/- deficiency on liver aging. We found that old Polμ(-/- mice (>20 month have greater liver regenerative capacity compared with wt animals. Old Polμ(-/- liver showed reduced genomic instability and increased apoptosis resistance. However, Polμ(-/- mice did not show an extended life span and other organs (e.g., heart aged normally. Our results suggest that Polμ deficiency activates transcriptional networks that reduce constitutive apoptosis, leading to enhanced liver repair at old age.

  10. SCID patients with ARTEMIS vs RAG deficiencies following HCT: increased risk of late toxicity in ARTEMIS-deficient SCID.

    Science.gov (United States)

    Schuetz, Catharina; Neven, Benedicte; Dvorak, Christopher C; Leroy, Sandrine; Ege, Markus J; Pannicke, Ulrich; Schwarz, Klaus; Schulz, Ansgar S; Hoenig, Manfred; Sparber-Sauer, Monika; Gatz, Susanne A; Denzer, Christian; Blanche, Stephane; Moshous, Despina; Picard, Capucine; Horn, Biljana N; de Villartay, Jean-Pierre; Cavazzana, Marina; Debatin, Klaus-Michael; Friedrich, Wilhelm; Fischer, Alain; Cowan, Morton J

    2014-01-09

    A subgroup of severe combined immunodeficiencies (SCID) is characterized by lack of T and B cells and is caused by defects in genes required for T- and B-cell receptor gene rearrangement. Several of these genes are also involved in nonhomologous end joining of DNA double-strand break repair, the largest subgroup consisting of patients with T(-)B(-)NK(+)SCID due to DCLRE1C/ARTEMIS defects. We postulated that in patients with ARTEMIS deficiency, early and late complications following hematopoietic cell transplantation might be more prominent compared with patients with T(-)B(-)NK(+)SCID caused by recombination activating gene 1/2 (RAG1/2) deficiencies. We analyzed 69 patients with ARTEMIS and 76 patients with RAG1/2 deficiencies who received transplants from either HLA-identical donors without conditioning or from HLA-nonidentical donors without or with conditioning. There was no difference in survival or in the incidence or severity of acute graft-versus-host disease regardless of exposure to alkylating agents. Secondary malignancies were not observed. Immune reconstitution was comparable in both groups, however, ARTEMIS-deficient patients had a significantly higher occurrence of infections in long-term follow-up. There is a highly significant association between poor growth in ARTEMIS deficiency and use of alkylating agents. Furthermore, abnormalities in dental development and endocrine late effects were associated with alkylation therapy in ARTEMIS deficiency.

  11. 雨生红球藻合成虾青素过程中的分泌铵离子%Concomitant NH+4 Secretion During Astaxanthin Synthesis in Haematococcus pluvialis Under High Irradiance and Nitrogen Deficient Conditions

    Institute of Scientific and Technical Information of China (English)

    董庆霖; 赵学明; 刑向英; 胡建中; 巩继贤

    2007-01-01

    The present study is focused on protein degradation during astaxanthin synthesis in Haematococcus pluvialis under high irradiance and nitrogen deficient conditions. It was found that with the onset of astaxanthin synthesis in the cultures of high light and nitrogen-free (HF), high light and nitrogen-repletion (HR), and low light and nitrogen-free (LF), (1) endopeptidase (EP) activities increased along with decrease in protein content, (2) aspar-agine in HF and HR rose significantly before the first 4 and 5 day, but fell after that time. While, it increased slowly and continuously in LF, (3) ammonium increased continuously in HF and HR, whereas in LF, it was detected on the sixth day, and increased slowly on the following days. By contrast, in low light and nitrogen-repletion culture, (LR), the contents of protein and asparagine as well as EP activity were maintained relatively constant, no astaxanthin and ammonium were detected. Furthermore, when HF was sealed and bubbled with CO2-free gas (O2 and N2), astaxanthin content increased as the protein level decreased. These results strongly suggest that (1) the degraded protein served as a substitutive carbon source, to some extent, for the biosynthesis of astaxanthin, (2) endopeptidase was involved in the degradative process, (3) for detoxification, part of the ammonium generated by protein degradation was transiently stored in asparagine, whereas the rest of it was expelled into the culture broth.

  12. Increased mandibular condylar growth in mice with estrogen receptor beta deficiency

    OpenAIRE

    Yosuke, Kamiya; JING, Chen; Manshan, Xu; Achint, Utreja; Thomas, Choi; Hicham, Drissi; Sunil, Wadhwa

    2013-01-01

    Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERβ) inhibits axial skeletal growth in female mice. However, the role of ERβ in the mandibular condyle is largely unknown. We hypothesize that female ERβ deficient mice will have increased mandibular condylar growth compared with wild type (WT) female mice. This study examined female 7-...

  13. Myeloid differentiation factor 88 (MyD88-deficiency increases risk of diabetes in mice.

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    Toru Hosoi

    Full Text Available BACKGROUND: Multiple lines of evidence suggest innate immune response pathways to be involved in the development of obesity-associated diabetes although the molecular mechanism underling the disease is unknown. Recent observations suggest that saturated fatty acids can act as a ligand for toll-like receptor (TLR 4, which is thought to mediate obesity-associated insulin resistance. Myeloid differentiation factor 88 (MyD88 is an adapter protein for TLR/IL-1 receptor signaling, which is involved in the activation of inflammatory pathways. To evaluate molecular mechanisms linking obesity-associated diabetes down-stream of TLR4, we investigated physiological role of MyD88 in high-fat diet (HFD-induced obesity. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we found MyD88-deficient mice fed a HFD had increased circulating levels of insulin, leptin and cholesterol, as well as liver dysfunction (increased induction of ALT levels, increased activation of JNK and cleavage of PARP, which were linked to the onset of severe diabetes. On the other hand, TNF-alpha would not be involved in HFD-induced diabetes in MyD88-deficient mice, because TNF-alpha level was attenuated in MyD88-deficient mice fed with HFD. CONCLUSIONS/SIGNIFICANCE: The present finding of an unexpected role for MyD88 in preventing diabetes may provide a potential novel target/strategy for treating metabolic syndrome.

  14. AHNAK deficiency promotes browning and lipolysis in mice via increased responsiveness to β-adrenergic signalling.

    Science.gov (United States)

    Shin, Jae Hoon; Lee, Seo Hyun; Kim, Yo Na; Kim, Il Yong; Kim, Youn Ju; Kyeong, Dong Soo; Lim, Hee Jung; Cho, Soo Young; Choi, Junhee; Wi, Young Jin; Choi, Jae-Hoon; Yoon, Yeo Sung; Bae, Yun Soo; Seong, Je Kyung

    2016-03-18

    In adipose tissue, agonists of the β3-adrenergic receptor (ADRB3) regulate lipolysis, lipid oxidation, and thermogenesis. The deficiency in the thermogenesis induced by neuroblast differentiation-associated protein AHNAK in white adipose tissue (WAT) of mice fed a high-fat diet suggests that AHNAK may stimulate energy expenditure via development of beige fat. Here, we report that AHNAK deficiency promoted browning and thermogenic gene expression in WAT but not in brown adipose tissue of mice stimulated with the ADRB3 agonist CL-316243. Consistent with the increased thermogenesis, Ahnak(-/-) mice exhibited an increase in energy expenditure, accompanied by elevated mitochondrial biogenesis in WAT depots in response to CL-316243. Additionally, AHNAK-deficient WAT contained more eosinophils and higher levels of type 2 cytokines (IL-4/IL-13) to promote browning of WAT in response to CL-316243. This was associated with enhanced sympathetic tone in the WAT via upregulation of adrb3 and tyrosine hydroxylase (TH) in response to β-adrenergic activation. CL-316243 activated PKA signalling and enhanced lipolysis, as evidenced by increased phosphorylation of hormone-sensitive lipase and release of free glycerol in Ahnak(-/-) mice compared to wild-type mice. Overall, these findings suggest an important role of AHNAK in the regulation of thermogenesis and lipolysis in WAT via β-adrenergic signalling.

  15. Increasing subtropical North Pacific Ocean nitrogen fixation since the Little Ice Age

    Science.gov (United States)

    Sherwood, Owen A.; Guilderson, Thomas P.; Batista, Fabian C.; Schiff, John T.; McCarthy, Matthew D.

    2014-01-01

    The North Pacific subtropical gyre (NPSG) plays a major part in the export of carbon and other nutrients to the deep ocean. Primary production in the NPSG has increased in recent decades despite a reduction in nutrient supply to surface waters. It is thought that this apparent paradox can be explained by a shift in plankton community structure from mostly eukaryotes to mostly nitrogen-fixing prokaryotes. It remains uncertain, however, whether the plankton community domain shift can be linked to cyclical climate variability or a long-term global warming trend. Here we analyse records of bulk and amino-acid-specific 15N/14N isotopic ratios (δ15N) preserved in the skeletons of long-lived deep-sea proteinaceous corals collected from the Hawaiian archipelago; these isotopic records serve as a proxy for the source of nitrogen-supported export production through time. We find that the recent increase in nitrogen fixation is the continuation of a much larger, centennial-scale trend. After a millennium of relatively minor fluctuation, δ15N decreases between 1850 and the present. The total shift in δ15N of -2 per mil over this period is comparable to the total change in global mean sedimentary δ15N across the Pleistocene-Holocene transition, but it is happening an order of magnitude faster. We use a steady-state model and find that the isotopic mass balance between nitrate and nitrogen fixation implies a 17 to 27 per cent increase in nitrogen fixation over this time period. A comparison with independent records suggests that the increase in nitrogen fixation might be linked to Northern Hemisphere climate change since the end of the Little Ice Age.

  16. BRCA1 deficiency increases the sensitivity of ovarian cancer cells to auranofin

    Energy Technology Data Exchange (ETDEWEB)

    Oommen, Deepu [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom); Yiannakis, Dennis [Plymouth Oncology Centre, Derriford Hospital, Plymouth Hospitals NHS Trust, Plymouth PL6 8DH (United Kingdom); Jha, Awadhesh N., E-mail: a.jha@plymouth.ac.uk [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom)

    2016-02-15

    Highlights: • BRCA1 deficient cancer cells exhibit increased DNA damage upon auranofin treatment. • Auranofin induces apoptosis in BRCA1 deficient cancer cells despite the activation of Nrf2. • Antioxidant protects BRCA1 deficient cancer cells from auranofin. - Abstract: Auranofin, a thioredoxin reductase inhibitor and an anti-rheumatic drug is currently undergoing phase 2 clinical studies for repurposing to treat recurrent epithelial ovarian cancer. Previous studies have established that auranofin exerts its cytotoxic activity by increasing the production of reactive oxygen species (ROS). Breast cancer 1, early onset (BRCA1) is a DNA repair protein whose functional status is critical in the prognosis of ovarian cancer. Apart from its key role in DNA repair, BRCA1 is also known to modulate cellular redox homeostasis by regulating the stability of anti-oxidant transcription factor, nuclear factor erythroid 2—related factor 2 (Nrf2) via direct protein–protein interaction. However, it is currently unknown whether BRCA1 modulates the sensitivity of ovarian cancer cells to auranofin. Here we report that BRCA1-depleted cells exhibited increased DNA double strand breaks (DSBs) and decreased clonogenic cell survival upon auranofin treatment. Interestingly, auranofin induced the expression of Nrf2 in BRCA1-depleted cells suggesting its regulation independent of BRCA1. Furthermore, anti-oxidant agent, N-acetyl cysteine (NAC) protected BRCA1-depleted cells from DNA damage and apoptosis induced by auranofin. Our study suggests that accumulated lethal DSBs resulting from the oxidative damage render BRCA1 deficient cells more sensitive to auranofin despite the activation of Nrf2.

  17. Analyzing the Effects of Nitrogen Deficiency on the PHB Production of Methylosinus trichosporium OB3b

    Science.gov (United States)

    Kyauk, E.

    2011-12-01

    Polyhydroxybutyrate (PHB) is a biodegradable thermoplastic that is produced by various microorganisms. Because of its potential to replace conventional plastics, it has been closely researched in the past few years. Methanotrophic bacteria, bacteria that consume methane, produce this bioplastic when it lacks certain nutrients. The utilization of methane to produce PHB shows much promise as methane is a cheap, plentiful gas. In this study, we observed the methanotroph, Methylosinus trichosporium OB3b , and its yield of PHB in the absence of nitrogen. The optical density of Methylosinus trichosporium OB3b was measured in order to observe cell growth and PHB production patterns over a 48 hour period.

  18. TMEM175 deficiency impairs lysosomal and mitochondrial function and increases α-synuclein aggregation

    Science.gov (United States)

    Jinn, Sarah; Drolet, Robert E.; Cramer, Paige E.; Wong, Andus Hon-Kit; Toolan, Dawn M.; Gretzula, Cheryl A.; Voleti, Bhavya; Vassileva, Galya; Disa, Jyoti; Tadin-Strapps, Marija; Stone, David J.

    2017-01-01

    Parkinson disease (PD) is a neurodegenerative disorder pathologically characterized by nigrostriatal dopamine neuron loss and the postmortem presence of Lewy bodies, depositions of insoluble α-synuclein, and other proteins that likely contribute to cellular toxicity and death during the disease. Genetic and biochemical studies have implicated impaired lysosomal and mitochondrial function in the pathogenesis of PD. Transmembrane protein 175 (TMEM175), the lysosomal K+ channel, is centered under a major genome-wide association studies peak for PD, making it a potential candidate risk factor for the disease. To address the possibility that variation in TMEM175 could play a role in PD pathogenesis, TMEM175 function was investigated in a neuronal model system. Studies confirmed that TMEM175 deficiency results in unstable lysosomal pH, which led to decreased lysosomal catalytic activity, decreased glucocerebrosidase activity, impaired autophagosome clearance by the lysosome, and decreased mitochondrial respiration. Moreover, TMEM175 deficiency in rat primary neurons resulted in increased susceptibility to exogenous α-synuclein fibrils. Following α-synuclein fibril treatment, neurons deficient in TMEM175 were found to have increased phosphorylated and detergent-insoluble α-synuclein deposits. Taken together, data from these studies suggest that TMEM175 plays a direct and critical role in lysosomal and mitochondrial function and PD pathogenesis and highlight this ion channel as a potential therapeutic target for treating PD. PMID:28193887

  19. Oily fish increases iron bioavailability of a phytate rich meal in young iron deficient women.

    Science.gov (United States)

    Navas-Carretero, Santiago; Pérez-Granados, Ana M; Sarriá, Beatriz; Carbajal, Angeles; Pedrosa, Mercedes M; Roe, Mark A; Fairweather-Tait, Susan J; Vaquero, M Pilar

    2008-02-01

    Iron deficiency is a major health problem worldwide, and is associated with diets of low iron bioavailability. Non-heme iron absorption is modulated by dietary constituents, one of which is the so-called "meat factor", present in meat, fish (oily and lean) and poultry, which is an important enhancer of iron absorption in humans. Food processing also affects iron bioavailability. To evaluate the effect of consuming sous vide cooked salmon fish on non-heme iron bioavailability from a bean meal, rich in phytate, in iron-deficient women. Randomized crossover trial in 21 young women with low iron stores (ferritin Sous vide cooked salmon fish increases iron absorption from a high phytate bean meal in humans.

  20. The effect of increased temperature and nitrogen deposition on decomposition in bogs

    NARCIS (Netherlands)

    Breeuwer, A.J.G.; Heijmans, M.M.P.D.; Robroek, B.J.M.; Limpens, J.; Berendse, F.

    2008-01-01

    Despite their low primary production, ombrotrophic peatlands have a considerable potential to store atmospheric carbon as a result of their extremely low litter decomposition rates. Projected changes in temperature and nitrogen (N) deposition may increase decomposition rates by their positive effect

  1. Nutritional constraints in ombrotrophic Sphagnum plants under increasing atmospheric nitrogen deposition in Europe

    NARCIS (Netherlands)

    Bragazza, L.; Tahvanainen, T.; Kutnar, L.; Rydin, H.; Limpens, J.; Hajek, M.; Grosvernier, P.; Hansen, I.; Lacumin, P.; Gerdol, R.

    2004-01-01

    We studied the effects of increasing levels of atmospheric nitrogen (N) deposition on nutrient limitation of ombrotrophic Sphagnum plants. • Fifteen mires in 11 European countries were selected across a natural gradient of bulk atmospheric N deposition from 0.1 to 2 g/m2 year-1. Nutritional constrai

  2. Overweight increases risk of first trimester hypothyroxinaemia in iodine-deficient pregnant women.

    Science.gov (United States)

    Gowachirapant, Sueppong; Melse-Boonstra, Alida; Winichagoon, Pattanee; Zimmermann, Michael B

    2014-01-01

    Hypothyroxinaemia early in pregnancy may impair fetal brain development. Increased body weight has been associated with low thyroxine concentrations in non-pregnant women. In pregnant women, morbid maternal obesity is a risk factor for thyroid dysfunction. But whether lesser degrees of overweight that are much more common could be a risk factor for hypothyroxinaemia in pregnancy is unclear. The objective of this study was to investigate if overweight increases risk for thyroid dysfunction, and specifically hypothyroxinaemia, in iodine-deficient pregnant women. We performed a cross-sectional study at first hospital visit among healthy Thai pregnant women. We measured weight and height, urinary iodine concentration (UIC), serum thyroid hormones and thyroglobulin. Pre-pregnancy weight and relevant dietary factors were determined by questionnaire, and body mass index (BMI) was used to classify weight status. Among 514 women (mean gestational age, 11 weeks) with a median UIC of 111 μg dL(-1) , indicating mild iodine deficiency, 12% had low free thyroxine (fT4) concentrations: 3% had overt hypothyroidism; 7% had subclinical hypothyroidism; and 8% had isolated hypothyroxinaemia. Based on pre-pregnancy BMI, 26% of women were overweight or obese. In a multiple regression model, BMI was a negative predictor of fT4 (β = -0.20, P Iodine-deficient pregnant Thai women who are overweight have a 3.6-fold higher risk of hypothyroxinaemia in the first trimester compared to normal weight women. Targeted screening should consider overweight a potential risk factor for thyroid dysfunction in pregnant women in iodine-deficient areas. © 2013 John Wiley & Sons Ltd.

  3. Combination of inoculation methods of Azospirilum brasilense with broadcasting of nitrogen fertilizer increases corn yield

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    Tânia Maria Müller

    2015-01-01

    Full Text Available Nitrogen (N is the most limiting nutrient for corn production. Thereby, the goal of the paper was to evaluate inoculation methods of Azospirillum brasilense in order to partially supply N required by the crop. The experiment was carried out in Guarapuava, PR, Brasil, in 2011/2012 growing season. Randomized blocks with factorial 3 inoculation methods (seed treatment, planting furrow and non-inoculated control x 5 doses of nitrogen (0, 75, 150, 225 and 300kg ha-1 x 8 replications was used as the experimental design. Leaf are index, foliar nitrogen content, total chlorophyll, grains per ear and yield were evaluated. There was significant interaction between inoculation methods and nitrogen fertilization to leaf area index, but not for yield. Inoculation with the diazotrophic bacteria provided yield increase of 702kg ha-1 for inoculation in seeding furrow and 432kg ha-1 for inoculation in seed treatment compared to the control, but both treatments did not differ between each other. Furthermore, total chlorophyll, grains per ear and yield were positively affected, with quadratic response, by the nitrogen fertilization in broadcasting

  4. Increased anxiety-like behavior in neuropsin (kallikrein-related peptidase 8) gene-deficient mice.

    Science.gov (United States)

    Horii, Yoichiro; Yamasaki, Nobuyuki; Miyakawa, Tsuyoshi; Shiosaka, Sadao

    2008-06-01

    Neuropsin (kallikrein-related peptidase 8) is concentrated in the hippocampus, amygdala, olfactory bulb, and prefrontal cortex. Earlier studies showed that protease deficiency causes a significant impairment of early-phase long-term potentiation in the Schaffer collateral pathway and hippocampus-dependent memory in the Y maze and Morris water maze (Z. Chen et al., 1995; A. Hirata et al., 2001; H. Tamura et al., 2006). In addition to neuropsin's participation in the hippocampal memory, amygdalar and cortical localization of the gene suggests extrahippocampal behavioral function, and the authors therefore examined neuropsin-deficient mice, including tests of sensory motor reflex, open field, light-dark transition, Rota-Rod, elevated plus-maze, hot plate, startle response-prepulse inhibition, Porsolt forced swim, Barnes maze, eight-arm radial maze, and contextual and cued fear conditioning tests. Here, the authors found increased anxiety in neuropsin-deficient mice, suggesting the involvement of this protease in emotional responses. (Copyright) 2008 APA, all rights reserved.

  5. Adrenergic deficiency leads to impaired electrical conduction and increased arrhythmic potential in the embryonic mouse heart.

    Science.gov (United States)

    Baker, Candice; Taylor, David G; Osuala, Kingsley; Natarajan, Anupama; Molnar, Peter J; Hickman, James; Alam, Sabikha; Moscato, Brittany; Weinshenker, David; Ebert, Steven N

    2012-07-01

    To determine if adrenergic hormones play a critical role in the functional development of the cardiac pacemaking and conduction system, we employed a mouse model where adrenergic hormone production was blocked due to targeted disruption of the dopamine β-hydroxylase (Dbh) gene. Immunofluorescent histochemical evaluation of the major gap junction protein, connexin 43, revealed that its expression was substantially decreased in adrenergic-deficient (Dbh-/-) relative to adrenergic-competent (Dbh+/+ and Dbh+/-) mouse hearts at embryonic day 10.5 (E10.5), whereas pacemaker and structural protein staining appeared similar. To evaluate cardiac electrical conduction in these hearts, we cultured them on microelectrode arrays (8×8, 200 μm apart). Our results show a significant slowing of atrioventricular conduction in adrenergic-deficient hearts compared to controls (31.4±6.4 vs. 15.4±1.7 ms, respectively, pheart rate and rhythm, mouse hearts from adrenergic-competent and deficient embryos were cultured ex vivo at E10.5, and heart rates were measured before and after challenge with the β-adrenergic receptor agonist, isoproterenol (0.5 μM). On average, all hearts showed increased heart rate responses following isoproterenol challenge, but a significant (phearts. These results show that adrenergic hormones may influence heart development by stimulating connexin 43 expression, facilitating atrioventricular conduction, and helping to maintain cardiac rhythm during a critical phase of embryonic development.

  6. Prediabetes is associated with an increased risk of testosterone deficiency, independent of obesity and metabolic syndrome.

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    Chen-Hsun Ho

    Full Text Available OBJECTIVE: The association between type 2 diabetes and low testosterone has been well recognized. However, testosterone levels in men with prediabetes have been rarely reported. We aimed to investigate whether prediabetes was associated with an increased risk of testosterone deficiency. METHODS: This study included 1,306 men whose sex hormones was measured during a medical examination. Serum total testosterone and sex hormone-binding globulin were measured; free and bioavailable testosterone concentrations were calculated by Vermeulen's formula. Prediabetes was defined by impaired fasting glucose (IFG, impaired postprandial glucose (IPG, or glycated hemoglobin (HbA1c 5.7%-6.4%. Logistic regression was performed to obtain the odds ratios (OR for subnormal total testosterone (<300 ng/dL or free testosterone (<6 ng/dL in prediabetic and diabetic men compared with normoglycemic individuals, while adjusting for age, BMI, waist circumference, and metabolic syndrome (MetS. RESULTS: Normoglycemia, prediabetes, and diabetes were diagnosed in 577 (44.2%, 543 (41.6%, and 186 (14.2% men, respectively. Prediabetes was associated with an increased risk of subnormal total testosterone compared to normoglycemic individuals (age-adjusted OR=1.87; 95%CI=1.38-2.54. The risk remained significant in all multivariate analyses. After adjusting for MetS, the OR in prediabetic men equals that of diabetic patients (1.49 versus 1.50. IFG, IPG, and HbA1c 5.7%-6.4% were all associated with an increased risk of testosterone deficiency, with different levels of significance in multivariate analyses. However, neither prediabetes nor diabetes was associated with subnormal free testosterone in multivariate analyses. CONCLUSIONS: Prediabetes is associated with an increased risk of testosterone deficiency, independent of obesity and MetS. After adjusting for MetS, the risk equals that of diabetes. Our data suggest that testosterone should be measured routinely in men with

  7. Endohedral nitrogen storage in carbon fullerene structures: Physisorption to chemisorption transition with increasing gas pressure

    Science.gov (United States)

    Barajas-Barraza, R. E.; Guirado-López, R. A.

    2009-06-01

    We present extensive pseudopotential density functional theory (DFT) calculations in order to analyze the structural properties and chemical reactivity of nitrogen molecules confined in spheroidal (C82) and tubelike (C110) carbon fullerene structures. For a small number of encapsulated nitrogens, the N2 species exist in a nonbonded state within the cavities and form well defined molecular conformations such as linear chains, zigzag arrays, as well as both spheroidal and tubular configurations. However, with increasing the number of stored molecules, the interaction among the confined nitrogens as well as between the N2 species and the fullerene wall is not always mainly repulsive. Actually, at high densities of the encapsulated gas, we found both adsorption of N2 to the inner carbon surface together with the formation of (N2)m molecular clusters. Total energy DFT calculations reveal that the shape of the interaction potential of a test molecule moving within the carbon cavities strongly varies with the number and proximity of the coadsorbed N2 from being purely repulsive to having short-range attractive contributions close to the inner wall. In particular, the latter are always found when a group of closely spaced nitrogens is located near the carbon cage (a fact that will naturally occur at high densities of the encapsulated gas), inducing the formation of covalent bonds between the N2 and the fullerene network. Interestingly, in some cases, the previous nitrogen adsorption to the inner surface is reversible by reducing the gas pressure. The calculated average density of states of our considered carbon compounds reveals the appearance of well defined features that clearly reflect the occurring structural changes and modifications in the adsorption properties in the systems. Our results clearly underline the crucial role played by confinement effects on the reactivity of our endohedral compounds, define this kind of materials as nonideal nanocontainers for high

  8. Effects of increased summer flooding on nitrogen dynamics in impounded mangroves.

    Science.gov (United States)

    Verhoeven, Jos T A; Laanbroek, Hendrikus J; Rains, Mark C; Whigham, Dennis F

    2014-06-15

    Mangroves are important for coastal protection, carbon sequestration and habitat provision for plants and animals in the tropics and subtropics. Mangroves are threatened by habitat destruction and sea level rise, but management activities such as impounding for mosquito control can also have negative effects. We studied the effects of Rotational Impoundment Management (RIM) on nitrogen dynamics in impoundments dominated by three types of Black mangrove (Avicennia germinans) stands along the Indian River Lagoon (Florida). RIM, designed for noxious insect control, involves pumping estuarine water into impoundments in this area during spring and summer to raise water levels by 30 cm. We compared aspects of the nitrogen cycle before and after the start of the RIM and measured the same variables in an impoundment without RIM management. RIM led to the accumulation of ammonium in the substrate which coincided with a lowering of nitrification rates and decreased denitrification rates. Salt pan habitats dominated by dwarf mangroves became less saline following RIM initiation. Shoot growth of mangroves increased in response to higher nitrogen availability and lower pore water salinity. Mangrove responses were greatest in areas with dwarf and sparse mangrove cover. Overall, RIM resulted in lower nitrification and denitrification leading to lower nitrogen losses and increased Black mangrove growth, all benefits of RIM beyond those associated with noxious insect control.

  9. Increased sensitivity to salt stress in tocopherol-deficient Arabidopsis mutants growing in a hydroponic system

    Science.gov (United States)

    Ellouzi, Hasna; Hamed, Karim Ben; Cela, Jana; Müller, Maren; Abdelly, Chedly; Munné-Bosch, Sergi

    2013-01-01

    Recent studies suggest that tocopherols could play physiological roles in salt tolerance but the mechanisms are still unknown. In this study, we analyzed changes in growth, mineral and oxidative status in vte1 and vte4 Arabidopsis thaliana mutants exposed to salt stress. vte1 and vte4 mutants lack α-tocopherol, but only the vte1 mutant is additionally deficient in γ-tocopherol. Results showed that a deficiency in vitamin E leads to reduced growth and increased oxidative stress in hydroponically-grown plants. This effect was observed at early stages, not only in rosettes but also in roots. The vte1 mutant was more sensitive to salt-induced oxidative stress than the wild type and the vte4 mutant. Salt sensitivity was associated with (i) high contents of Na+, (ii) reduced efficiency of PSII photochemistry (Fv/Fm ratio) and (iii) more pronounced oxidative stress as indicated by increased hydrogen peroxide and malondialdeyde levels. The vte 4 mutant, which accumulates γ- instead of α-tocopherol showed an intermediate sensitivity to salt stress between the wild type and the vte1 mutant. Contents of abscisic acid, jasmonic acid and the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid were higher in the vte1 mutant than the vte4 mutant and wild type. It is concluded that vitamin E-deficient plants show an increased sensitivity to salt stress both in rosettes and roots, therefore indicating the positive role of tocopherols in stress tolerance, not only by minimizing oxidative stress, but also controlling Na+/K+ homeostasis and hormonal balance. PMID:23299430

  10. Increased sensitivity to salt stress in tocopherol-deficient Arabidopsis mutants growing in a hydroponic system.

    Science.gov (United States)

    Ellouzi, Hasna; Hamed, Karim Ben; Cela, Jana; Müller, Maren; Abdelly, Chedly; Munné-Bosch, Sergi

    2013-02-01

    Recent studies suggest that tocopherols could play physiological roles in salt tolerance but the mechanisms are still unknown. In this study, we analyzed changes in growth, mineral and oxidative status in vte1 and vte4 Arabidopsis thaliana mutants exposed to salt stress. vte1 and vte4 mutants lack α-tocopherol, but only the vte1 mutant is additionally deficient in γ-tocopherol. Results showed that a deficiency in vitamin E leads to reduced growth and increased oxidative stress in hydroponically-grown plants. This effect was observed at early stages, not only in rosettes but also in roots. The vte1 mutant was more sensitive to salt-induced oxidative stress than the wild type and the vte4 mutant. Salt sensitivity was associated with (i) high contents of Na(+), (ii) reduced efficiency of PSII photochemistry (Fv/Fm ratio) and (iii) more pronounced oxidative stress as indicated by increased hydrogen peroxide and malondialdeyde levels. The vte 4 mutant, which accumulates γ- instead of α-tocopherol showed an intermediate sensitivity to salt stress between the wild type and the vte1 mutant. Contents of abscisic acid, jasmonic acid and the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid were higher in the vte1 mutant than the vte4 mutant and wild type. It is concluded that vitamin E-deficient plants show an increased sensitivity to salt stress both in rosettes and roots, therefore indicating the positive role of tocopherols in stress tolerance, not only by minimizing oxidative stress, but also controlling Na(+)/K(+) homeostasis and hormonal balance.

  11. Historical nitrogen content of bryophyte tissue as an indicator of increased nitrogen deposition in the Cape Metropolitan Area, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D. [Botany Department, University of Cape Town, Rondebosch 7701 (South Africa); Stock, W.D. [Botany Department, University of Cape Town, Rondebosch 7701 (South Africa); Centre for Ecosystem Management, School of Natural Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Perth, WA 6027 (Australia)], E-mail: w.stock@ecu.edu.au; Hedderson, T. [Botany Department, University of Cape Town, Rondebosch 7701 (South Africa)

    2009-03-15

    Information on changes in precipitation chemistry in the rapidly expanding Cape Metropolitan Area (CMA) of South Africa is scarce. To obtain a long-term record of N deposition we investigated changes in moss foliar N, C:N ratios and nitrogen isotope values that might reflect precipitation chemistry. Tissue from 9 species was obtained from herbarium specimens collected between 1875 and 2000 while field samples were collected in 2001/2002. There is a strong trend of increasing foliar N content in all mosses collected over the past century (1.32-1.69 %N). Differences exist between ectohydric mosses which have higher foliar N than the mixohydric group. C:N ratios declined while foliar {delta}{sup 15}N values showed no distinct pattern. From relationships between moss tissue N and N deposition rates we estimated an increase of 6-13 kg N ha{sup -1} a{sup -1} since 1950. Enhanced N deposition rates of this magnitude could lead to biodiversity losses in native ecosystems. - This study of bryophyte tissue nutrient contents shows a historical increase in N deposition rates to the low nutrient adapted plant biodiversity hotspot in the Western Cape, South Africa.

  12. Responses of Azospirillum brasilense to nitrogen deficiency and to wheat lectin: a diffuse reflectance infrared fourier transform (DRIFT) spectroscopic study.

    Science.gov (United States)

    Kamnev, Alexander A; Sadovnikova, Julia N; Tarantilis, Petros A; Polissiou, Moschos G; Antonyuk, Lyudmila P

    2008-11-01

    For the rhizobacterium Azospirillum brasilense, the optimal nutritional range of C:N ratios corresponds to the presence of malate (ca. 3 to 5 g l(-1) of its sodium salt) and ammonium (ca. 0.5 to 3 g l(-1) of NH4Cl) as preferred carbon and nitrogen sources, respectively. This microaerophilic aerotactic bacterium is known to have a narrow optimal oxygen concentration range of ca. 3 to 5 microM, which is 1.2% to 2% of oxygen solubility in air-saturated water under normal conditions. In this work, the effects of stress conditions (bound-nitrogen deficiency related to a high C:N ratio in the medium; excess of oxygen) on aerobically grown A. brasilense Sp245, a native wheat-associated endophyte, were investigated in the absence and presence of wheat germ agglutinin (WGA, plant stress protein and a molecular host-plant signal for the bacterium) using FTIR spectroscopy of whole cells in the diffuse reflectance mode (DRIFT). The nutritional stress resulted in the appearance of prominent spectroscopic signs of poly-3-hydroxybutyrate (PHB) accumulation in the bacterial cells; in addition, splitting of the amide I band related to bacterial cellular proteins indicated some stress-induced alterations in their secondary structure components. Similar structural changes were observed in the presence of nanomolar WGA both in stressed A. brasilense cells and under normal nutritional conditions. Comparative analysis of the data obtained and the relevant literature data indicated that the stress conditions applied (which resulted in the accumulation of PHB involved in stress tolerance) and/or the presence of nanomolar concentrations of WGA induced synthesis of bacterial cell-surface (glyco)proteins rich in beta-structures, that could be represented by hemagglutinin and/or porin.

  13. Loss of Mrap2 is associated with Sim1 deficiency and increased circulating cholesterol

    Science.gov (United States)

    Novoselova, T V; Larder, R; Rimmington, D; Lelliott, C; Wynn, E H; Gorrigan, R J; Tate, P H; Guasti, L; O’Rahilly, S; Logan, D W; Coll, A P; Chan, L F

    2016-01-01

    Melanocortin receptor accessory protein 2 (MRAP2) is a transmembrane accessory protein predominantly expressed in the brain. Both global and brain-specific deletion of Mrap2 in mice results in severe obesity. Loss-of-function MRAP2 mutations have also been associated with obesity in humans. Although MRAP2 has been shown to interact with MC4R, a G protein-coupled receptor with an established role in energy homeostasis, appetite regulation and lipid metabolism, the mechanisms through which loss of MRAP2 causes obesity remains uncertain. In this study, we used two independently derived lines of Mrap2 deficient mice (Mrap2tm1a/tm1a) to further study the role of Mrap2 in the regulation of energy balance and peripheral lipid metabolism. Mrap2tm1a/tm1a mice have a significant increase in body weight, with increased fat and lean mass, but without detectable changes in food intake or energy expenditure. Transcriptomic analysis showed significantly decreased expression of Sim1, Trh, Oxt and Crh within the hypothalamic paraventricular nucleus of Mrap2tm1a/tm1a mice. Circulating levels of both high-density lipoprotein and low-density lipoprotein were significantly increased in Mrap2 deficient mice. Taken together, these data corroborate the role of MRAP2 in metabolic regulation and indicate that, at least in part, this may be due to defective central melanocortin signalling. PMID:27106110

  14. Fas/CD95 deficiency in ApcMin/+ mice increases intestinal tumor burden.

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    Hector Guillen-Ahlers

    Full Text Available BACKGROUND: Fas, a member of the tumor necrosis family, is responsible for initiating the apoptotic pathway when bound to its ligand, Fas-L. Defects in the Fas-mediated apoptotic pathway have been reported in colorectal cancer. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, a variant of the Apc(Min/+ mouse, a model for the human condition, Familial Adenomatous Polyposis (FAP, was generated with an additional deficiency of Fas (Apc(Min/+/Fas(lpr by cross-breeding Apc(Min/+ mice with Fas deficient (Fas(lpr mice. One of the main limitations of the Apc(Min/+ mouse model is that it only develops benign polyps. However, Apc(Min/+/Fas(lpr mice presented with a dramatic increase in tumor burden relative to Apc(Min/+ mice and invasive lesions at advanced ages. Proliferation and apoptosis markers revealed an increase in cellular proliferation, but negligible changes in apoptosis, while p53 increased at early ages. Fas-L was lower in Apc(Min/+/Fas(lpr mice relative to Apc(Min/+ cohorts, which resulted in enhanced inflammation. CONCLUSIONS/SIGNIFICANCE: This study demonstrated that imposition of a Fas deletion in an Apc(Min/+ background results in a more aggressive phenotype of the Apc(Min/+ mouse model, with more rapid development of invasive intestinal tumors and a decrease in Fas-L levels.

  15. Female Nur77-deficient mice show increased susceptibility to diet-induced obesity.

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    Sonia Perez-Sieira

    Full Text Available Adipose tissue is essential in the regulation of body weight. The key process in fat catabolism and the provision of energy substrate during times of nutrient deprivation or enhanced energy demand is the hydrolysis of triglycerides and the release of fatty acids and glycerol. Nur77 is a member of the NR4A subfamily of nuclear receptors that plays an important metabolic role, modulating hepatic glucose metabolism and lipolysis in muscle. However, its endogenous role on white adipose tissue, as well as the gender dependency of these mechanisms, remains largely unknown. Male and female wild type and Nur77 deficient mice were fed with a high fat diet (45% calories from fat for 4 months. Mice were analyzed in vivo with the indirect calorimetry system, and tissues were analyzed by real-time PCR and Western blot analysis. Female, but not male Nur77 deficient mice, gained more weight and fat mass when compared to wild type mice fed with high fat diet, which can be explained by decreased energy expenditure. The lack of Nur77 also led to a decreased pHSL/HSL ratio in white adipose tissue and increased expression of CIDEA in brown adipose tissue of female Nur77 deficient mice. Overall, these findings suggest that Nur77 is an important physiological modulator of lipid metabolism in adipose tissue and that there are gender differences in the sensitivity to deletion of the Nur77 signaling. The decreased energy expenditure and the actions of Nur77 on liver, muscle, brown and white adipose tissue contribute to the increased susceptibility to diet-induced obesity in females lacking Nur77.

  16. Deficiency of retinaldehyde dehydrogenase 1 induces BMP2 and increases bone mass in vivo.

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    Shriram Nallamshetty

    Full Text Available The effects of retinoids, the structural derivatives of vitamin A (retinol, on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA and its precursor all trans retinaldehyde (Rald, exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1, the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT demonstrated that Aldh1a1-deficient (Aldh1a1(-/- female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1(-/- mice. In serum assays, Aldh1a1(-/- mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1(-/- mesenchymal stem cells (MSCs expressed significantly higher levels of bone morphogenetic protein 2 (BMP2 and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1(-/- mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1(-/- mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling.

  17. Detection of nitrogen deficiency QTL in juvenile wild barley introgression lines growing in a hydroponic system

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    Hoffmann Astrid

    2012-10-01

    Full Text Available Abstract Background In this report we studied the genetic regulation of juvenile development of wild barley introgression lines (S42ILs under two contrasting hydroponic nitrogen (N supplies. Ten shoot and root related traits were examined among 42 S42ILs and the recurrent parent ‘Scarlett’. The traits included tiller number, leaf number, plant height, leaf and root length, leaf to root length ratio, shoots and root dry weight, shoot to root weight ratio, and chlorophyll content. Our aims were (1 to test the suitability of a hydroponic system for early detection of favourable S42ILs, (2 to locate quantitative trait loci (QTL that control the examined traits, (3 to identify favourable wild barley alleles that improve trait performances in regard to N treatment and, finally, (4 to validate the identified QTL through comparison with previously reported QTL originating from the same parental cross. Results The phenotypic data were analysed in a mixed model association study to detect QTL. The post-hoc Dunnett test identified 28 S42ILs that revealed significant (P Hsp effects for tiller number, leaf number, leaf length, plant height and leaf to root ratio on the long arm of chromosome 7H. These QTL correspond to QTL for ears per plant and plant height that were previously detected in field trials conducted with the same S42ILs or with the S42 population. Conclusion Our results suggest that the QTL we identified under hydroponic N cultivation partly correspond to QTL detected in field experiments. Due to this finding, screening of plants in early developmental stages grown in a hydroponic system may be a fast and cost effective method for early QTL detection and marker-assisted allelic selection, potentially speeding up elite barley breeding programs.

  18. Epidermal filaggrin deficiency mediates increased systemic T-helper 17 immune response

    DEFF Research Database (Denmark)

    Bonefeld, C. M.; Petersen, T. H.; Bandier, J.

    2016-01-01

    Background: Cellular T-helper (Th)17 infiltrates dominate skin inflammation in filaggrin-deficient flaky tail (ft/ft) mice, and Th17 cells are found in both the skin and blood of patients with acute atopic dermatitis. However, the potential role of loss-of-function mutations in the filaggrin gene...... (FLG) for increased peripheral Th17 cells is unclear. Objectives: To study whether mutations in FLG influence the frequency of peripheral Th17 cells. Methods: We studied blood samples from six adults with mutations in FLG and five controls without mutations for frequencies of cytokine-producing CD4+ T...... increased frequency of peripheral Th17 cells in FLG mutation carriers when compared with WT individuals. Mouse studies showed increased frequency of peripheral Th17 cells in adult ft/ft mice but not in 2-week-old ft/ft mice. Moreover, altered TCR Vβ-chain repertoire was found in ft/ft mice when compared...

  19. Increased Intimal Hyperplasia After Vascular Injury in Male Androgen Receptor-Deficient Mice

    DEFF Research Database (Denmark)

    Wilhelmson, Anna S; Fagman, Johan B; Johansson, Inger

    2016-01-01

    replacement to castrated male mice increased p27 mRNA in an AR-dependent manner. In conclusion, AR deficiency in male mice increases intimal hyperplasia in response to vascular injury, potentially related to the effects of androgens/AR to inhibit proliferation and migration of smooth muscle cells......., there was no difference in the reendothelialization in ARKO compared with control mice. Ex vivo, we observed increased outgrowth of vascular smooth muscle cells from ARKO compared with control aortic tissue explants; the number of outgrown cells was almost doubled in ARKO. In vitro, stimulation of human aortic vascular...... smooth muscle cells with a physiological T concentration inhibited both migration and proliferation of the cells. Analyzing the expression of central regulators of cell proliferation and migration, we found that mRNA and protein levels of p27 were lower in uninjured arteries from ARKO mice and that T...

  20. Increased mandibular condylar growth in mice with estrogen receptor beta deficiency.

    Science.gov (United States)

    Kamiya, Yosuke; Chen, Jing; Xu, Manshan; Utreja, Achint; Choi, Thomas; Drissi, Hicham; Wadhwa, Sunil

    2013-05-01

    Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERβ) inhibits axial skeletal growth in female mice. However, the role of ERβ in the mandibular condyle is largely unknown. We hypothesize that female ERβ-deficient mice will have increased mandibular condylar growth compared to wild-type (WT) female mice. This study examined female 7-day-old, 49-day-old, and 120-day-old WT and ERβ knockout (KO) mice. There was a significant increase in mandibular condylar cartilage thickness as a result of an increased number of cells, in the 49-day-old and 120-day-old female ERβ KO compared with WT controls. Analysis in 49-day-old female ERβ KO mice revealed a significant increase in collagen type X, parathyroid hormone-related protein (Pthrp), and osteoprotegerin gene expression and a significant decrease in receptor activator for nuclear factor κ B ligand (Rankl) and Indian hedgehog (Ihh) gene expression, compared with WT controls. Subchondral bone analysis revealed a significant increase in total condylar volume and a decrease in the number of osteoclasts in the 49-day-old ERβ KO compared with WT female mice. There was no difference in cell proliferation in condylar cartilage between the genotypes. However, there were differences in the expression of proteins that regulate the cell cycle; we found a decrease in the expression of Tieg1 and p57 in the mandibular condylar cartilage from ERβ KO mice compared with WT mice. Taken together, our results suggest that ERβ deficiency increases condylar growth in female mice by inhibiting the turnover of fibrocartilage.

  1. Cystatin B-deficient mice have increased expression of apoptosis and glial activation genes

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    Lieuallen, Kimberly; Pennacchio, Len A.; Park, Morgan; Myers, Richard M.; Lennon, Gregory G.

    2001-07-05

    Loss-of-function mutations in the cystatin B (Cstb) gene cause a neurological disorder known as Unverricht Lundborg disease (EPM1) in human patients. Mice that lack Cstb provide a mammalian model for EPM1 by displaying progressive ataxia and myoclonic seizures. We analyzed RNAs from brains of Cstb-deficient mice by using modified differential display, oligonucleotide microarray hybridization and quantitative reverse transcriptase polymerase chain reaction to examine the molecular consequences of the lack of Cstb. We identified seven genes that have consistently increased transcript levels in neurological tissues from the knockout mice. These genes are cathepsin S, C1q B-chain of complement (C1qB), beta-2-microglobulin, glial fibrillary acidic protein (Gfap), apolipoprotein D, fibronectin 1 and metallothionein II, which are expected to be involved in increased proteolysis, apoptosis and glial activation. The molecular changes in Cstb-deficient mice are consistent with the pathology found in the mouse model and may provide clues towards the identification of therapeutic points of intervention for EPM1 patients.

  2. Nitrogen balance of starting barrow pigs fed on increasing lysine levels

    Directory of Open Access Journals (Sweden)

    Ivan Moreira

    2004-03-01

    Full Text Available The effects of increasing lysine levels on nitrogen balance of pigs fed on low protein diets were evaluated. Four treatments (diets containing lysine levels (0.8, 1.0 1.2 and 1.4% were applied to 12 starting (20.0 ± 1.8 kg barrow pigs. Methionine, threonine and tryptophan were kept constant to the lysine ratio in all diets. Feces and urine were collected during a 5-day period. Nitrogen output in urine (NOU, total nitrogen output (TNO, nitrogen retention (NR, net protein utilization (NPU, biological value or feed protein (BVFP, urine urea nitrogen (UUN, and plasma urea nitrogen (PUN were determined. PUN showed high negative correlations with BVFP (-0.84, NPU (-0.76, and NR (-0.78 and a positive correlation (0.79 to NOU. Lowest nitrogen excretion and the best use of diet protein were obtained with 1.1% total lysine level. PUN is efficient to indicate amino acid for pigs.Foi realizado um experimento para se determinar o efeito de níveis crescentes de lisina sobre o balanço de nitrogênio de suínos, alimentados com rações de baixo teor protéico. Doze suínos machos castrados em fase inicial (20,0 ± 1,8 kg foram distribuídos em 4 tratamentos (dietas com níveis crescentes de lisina total (08, 1,0 1,2 e 1,4%. Os níveis de metionina, treonina e triptofano foram mantidos constantes em relação à lisina. Foram coletadas fezes e urina durante o período de cinco dias. Foram determinados os nitrogênios excretados na urina (NEU, total excretado (NTE, retido (NR, a utilização líquida da proteína (ULP, o valor biológico da proteína dietética (VBPD, o nitrogênio da uréia plasmática (NUP e urinária (NUU. O NUP foi altamente correlacionado com o VBPD (-0,84, ULP (-0,76, NEU (0,79 e NR (-0,78. O melhor aproveitamento da proteína dietética e a menor excreção de nitrogênio foram obtidos com 1,1% de lisina total. O NUP é eficiente para indicar a utilização de aminoácidos pelos suínos.

  3. Increased susceptibility to Salmonella infection in signal regulatory protein α-deficient mice.

    Science.gov (United States)

    Li, Lin-Xi; Atif, Shaikh M; Schmiel, Shirdi E; Lee, Seung-Joo; McSorley, Stephen J

    2012-09-01

    Recent studies have shed light on the connection between elevated erythropoetin production/spleen erythropoiesis and increased susceptibility to Salmonella infection. In this article, we provide another mouse model, the SIRPα-deficient (Sirpα⁻/⁻) mouse, that manifests increased erythropoiesis as well as heightened susceptibility to Salmonella infection. Sirpα⁻/⁻ mice succumbed to systemic infection with attenuated Salmonella, possessing significantly higher bacterial loads in both the spleen and the liver. Moreover, Salmonella-specific Ab production and Ag-specific CD4 T cells were reduced in Sirpα⁻/⁻ mice compared with wild-type controls. To further characterize the potential mechanism underlying SIRPα-dependent Ag-specific CD4 T cell priming, we demonstrate that lack of SIRPα expression on dendritic cells results in less efficient Ag processing and presentation in vitro. Collectively, these findings demonstrate an indispensable role of SIRPα for protective immunity to Salmonella infection.

  4. Aporphine alkaloid contents increase with moderate nitrogen supply in Annona diversifolia Saff. (Annonaceae) seedlings during diurnal periods.

    Science.gov (United States)

    Orozco-Castillo, José Agustín; Cruz-Ortega, Rocío; Martinez-Vázquez, Mariano; González-Esquinca, Alma Rosa

    2016-10-01

    Aporphine alkaloids are secondary metabolites that are obtained in low levels from species of the Annonaceae family. Nitrogen addition may increase the alkaloid content in plants. However, previous studies published did not consider that nitrogen could change the alkaloid content throughout the day. We conducted this short-term study to determine the effects of nitrogen applied throughout the diurnal period on the aporphine alkaloids via measurements conducted on the roots, stems and leaves of Annona diversifolia seedlings. The 60-day-old seedlings were cultured with the addition of three levels of nitrogen (0, 30 and 60 mM), and alkaloid extracts were analysed using high-performance liquid chromatography. The highest total alkaloid content was measured in the treatment with moderate nitrogen supply. Further, the levels of aporphine alkaloids changed significantly in the first few hours of the diurnal period. We conclude that aporphine alkaloid content increased with moderate nitrogen supply and exhibited diurnal variation.

  5. Nitrogen narcosis and ethyl alcohol increase the gain of the vestibular ocular reflex.

    Science.gov (United States)

    Hamilton, K; Fowler, B; Landolt, J; Porlier, G

    1989-03-01

    The effects of air, helium-oxygen (6.4 ATA), and ethyl alcohol (40% by volume at a dose of 1.5 ml/kg body weight) were examined on the gain, number of beats, and phase lag of the vestibular ocular reflex (VOR) by means of electronystagmography (n = 7). It was found that hyperbaric air and alcohol, both alone and in combination, produced approximately the same increase in the velocity of the slow phase component of the nystagmus, thereby elevating the gain of the system to unity. Hyperbaric helium-oxygen did not influence the gain. These findings suggest that nitrogen nacrosis differentially impairs the system controlling the VOR. It is proposed that this impairment may help to explain the disorientation sometimes associated with nitrogen narcosis.

  6. Parental vitamin D deficiency during pregnancy is associated with increased blood pressure in offspring via Panx1 hypermethylation.

    Science.gov (United States)

    Meems, Laura M G; Mahmud, Hasan; Buikema, Hendrik; Tost, Jörg; Michel, Sven; Takens, Janny; Verkaik-Schakel, Rikst N; Vreeswijk-Baudoin, Inge; Mateo-Leach, Irene V; van der Harst, Pim; Plösch, Torsten; de Boer, Rudolf A

    2016-12-01

    Vitamin D deficiency is one of the most common nutritional deficiencies worldwide. Maternal vitamin D deficiency is associated with increased susceptibility to hypertension in offspring, but the reasons for this remain unknown. The aim of this study was to determine if parental vitamin D deficiency leads to altered DNA methylation in offspring that may relate to hypertension. Male and female Sprague-Dawley rats were fed a standard or vitamin D-depleted diet. After 10 wk, nonsibling rats were mated. The conceived pups received standard chow. We observed an increased systolic and diastolic blood pressure in the offspring from depleted parents (F1-depl). Genome-wide methylation analyses in offspring identified hypermethylation of the promoter region of the Pannexin-1 (Panx1) gene in F1-depl rats. Panx1 encodes a hemichannel known to be involved in endothelial-dependent relaxation, and we demonstrated that in F1-depl rats the increase in blood pressure was associated with impaired endothelial relaxation of the large vessels, suggesting an underlying biological mechanism of increased blood pressure in children from parents with vitamin deficiency. Parental vitamin D deficiency is associated with epigenetic changes and increased blood pressure levels in offspring. Copyright © 2016 the American Physiological Society.

  7. Iron Deficiency-induced Increase of Root Branching Contributes to the Enhanced Root Ferric Chelate Reductase Activity

    Institute of Scientific and Technical Information of China (English)

    Chong-Wei Jin; Wei-Wei Chen; Zhi-Bin Meng; Shao-Jian Zheng

    2008-01-01

    In various plant species, Fe deficiency increases lateral root branching. However, whether this morphological alteration contributes to the Fe deficiency-induced physiological responses still remains to be demonstrated. In the present research, we demonstrated that the lateral root development of red clover (Trifolium pretense L.) was significantly enhanced by Fe deficient treatment, and the total lateral root number correlated well with the Fe deficiency-induced ferric chelate reductase (FCR) activity. By analyzing the results from Dasgan et al. (2002), we also found that although the two tomato genotypes line227/1 (P1) and Roza (P2) and their reciprocal F1 hybrid lines ("P1 × P2" and "P2 × P1 ") were cultured under two different lower Fe conditions (10-6 and 10-7 M FeEDDHA), their FCR activities are significantly correlated with the lateral root number. More interestingly, the -Fe chlorosis tolerant ability of these four tomato lines displays similar trends with the lateral root density. Taking these results together, it was proposed that the Fe deficiency-induced increases of the lateral root should play an important role in resistance to Fe deficiency, which may act as harnesses of a useful trait for the selection and breeding of more Fe-efficiant crops among the genotypes that have evolved a Fe deficiency-induced Fe uptake system.

  8. Is cobalamin deficiency associated with increased risk for all subtypes of postoperative delirium?

    Directory of Open Access Journals (Sweden)

    Wang LK

    2016-08-01

    Full Text Available Li-Kai Wang,1 Kuo-Mao Lan,1,2 Yao-Tsung Lin,1,2 Jen-Yin Chen1,3 1Department of Anesthesiology, Chi Mei Medical Center, Tainan, 2Department of Food Science and Applied Biotechnology, National Chung Hsing University, Taichung, 3Department of the Senior Citizen Service Management, Chia Nan University of Pharmacy and Science, Tainan, TaiwanIn a recent paper, Sevuk et al used the single-hospital-based database to investigate whether cobalamin (vitamin B12 deficiency increased the risk of postoperative delirium in patients aged .60 years undergoing cardiac surgery with cardiopulmonary bypass.1View the original paper by Sevuk and colleagues. 

  9. Increased concentration of vasopressin in plasma of essential fatty acid-deficient rats

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Jensen, B.; Warberg, J.

    1985-01-01

    The effect of essential fatty acid deficiency (EFA-D) on the plasma concentration of arginine-vasopressin (AVP) and the urinary AVP excretion was investigated. Weanling rats were fed a fat-free diet (FF-rats). Control rats received the same diet in which 6% by wt. of sucrose was replaced by arachis...... oil. After 4-6 weeks of feeding, urine and plasma were analysed for AVP, osmolality, sodium and potassium. When compared to control rats FF-rats had decreased urine volume (6.0 ± 1.6 ml/24 hr versus 11.7 ± 3.2 ml/24 hr), increased urine osmolality (2409 ± 691 mOsm/kg versus 1260 ± 434 m...

  10. Nitrogen addition, not initial phylogenetic diversity, increases litter decomposition by fungal communities

    Directory of Open Access Journals (Sweden)

    Anthony Stuart Amend

    2015-02-01

    Full Text Available Fungi play a critical role in the degradation of organic matter. Because different combinations of fungi result in different rates of decomposition, determining how climate change will affect microbial composition and function is fundamental to predicting future environments. Fungal response to global change is patterned by genetic relatedness, resulting in communities with comparatively low phylogenetic diversity. This may have important implications for the functional capacity of disturbed communities if lineages sensitive to disturbance also contain unique traits important for litter decomposition. Here we tested the relationship between phylogenetic diversity and decomposition rates. Leaf litter fungi were isolated from the field and deployed in microcosms as mock communities along a gradient of initial phylogenetic diversity, while species richness was held constant. Replicate communities were subject to nitrogen fertilization comparable to anthropogenic deposition levels. Carbon mineralization rates were measured over the course of sixty-six days. We found that nitrogen fertilization increased cumulative respiration by 24.8%, and that differences in respiration between fertilized and ambient communities diminished over the course of the experiment. Initial phylogenetic diversity failed to predict respiration rates or their change in response to nitrogen fertilization, and there was no correlation between community similarity and respiration rates. Last, we detected no phylogenetic signal in the contributions of individual isolates to respiration rates. Our results suggest that the degree to which phylogenetic diversity predicts ecosystem function will depend on environmental context.

  11. Growth and wood properties of Sitka spruce (Picea sitchensis (Bong.) Carr.) in nursing mixtures established on nitrogen-deficient mineral soils

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, A.D.; Watson, B.A. [Aberdeen Univ. (United Kingdom). Dept. of Forestry

    2000-07-01

    Rate of growth and wood properties of Sitka spruce (Picea sitchensis (Bong.) Carr.) were investigated in triplet mixtures with lodgepole pine (Pinus contorta Loud.) (Alaskan provenance) and Japanese larch (Larix kaempferi (Lamb.) Carr.), established on nitrogen-deficient, iron pan soils. These 'nursing' mixtures were compared with pure stands of Sitka spruce that had been either regularly or periodically fertilized with nitrogen. Japanese larch promoted a growth rate in Sitka spruce greater than that achieved in the lodgepole pine-nursed spruce and equivalent to the two pure spruce treatments over the duration of the experiment (current age 28 yrs). Growth of regularly fertilized pure Sitka spruce was not significantly greater than that of periodically fertilized pure spruce. Alaskan lodgepole pine controlled branch size on the lower part of the spruce stems more effectively than the other treatments, although this may have been a function of tree size. Branch characteristics of Japanese larch-nursed spruce, however, were similar to those of the pure spruce treatments. Japanese larch caused an imbalance in crown development in the spruce, although it is unclear from the present study whether this will have an influence on stem and wood quality by the end of the rotation. Overall, the evidence from this study suggests that Japanese larch is an effective nurse of Sitka spruce on nitrogen-deficient iron pans, maintaining a rate of growth similar to that of pure Sitka spruce periodically fertilized with nitrogen and higher than that observed in spruce nursed by Alaskan lodgepole pine.

  12. Adaptive aneuploidy protects against thiol peroxidase deficiency by increasing respiration via key mitochondrial proteins.

    Science.gov (United States)

    Kaya, Alaattin; Gerashchenko, Maxim V; Seim, Inge; Labarre, Jean; Toledano, Michel B; Gladyshev, Vadim N

    2015-08-25

    Aerobic respiration is a fundamental energy-generating process; however, there is cost associated with living in an oxygen-rich environment, because partially reduced oxygen species can damage cellular components. Organisms evolved enzymes that alleviate this damage and protect the intracellular milieu, most notably thiol peroxidases, which are abundant and conserved enzymes that mediate hydrogen peroxide signaling and act as the first line of defense against oxidants in nearly all living organisms. Deletion of all eight thiol peroxidase genes in yeast (∆8 strain) is not lethal, but results in slow growth and a high mutation rate. Here we characterized mechanisms that allow yeast cells to survive under conditions of thiol peroxidase deficiency. Two independent ∆8 strains increased mitochondrial content, altered mitochondrial distribution, and became dependent on respiration for growth but they were not hypersensitive to H2O2. In addition, both strains independently acquired a second copy of chromosome XI and increased expression of genes encoded by it. Survival of ∆8 cells was dependent on mitochondrial cytochrome-c peroxidase (CCP1) and UTH1, present on chromosome XI. Coexpression of these genes in ∆8 cells led to the elimination of the extra copy of chromosome XI and improved cell growth, whereas deletion of either gene was lethal. Thus, thiol peroxidase deficiency requires dosage compensation of CCP1 and UTH1 via chromosome XI aneuploidy, wherein these proteins support hydroperoxide removal with the reducing equivalents generated by the electron transport chain. To our knowledge, this is the first evidence of adaptive aneuploidy counteracting oxidative stress.

  13. Increase of Fungal Pathogenicity and Role of Plant Glutamine in Nitrogen-Induced Susceptibility (NIS) To Rice Blast

    Science.gov (United States)

    Huang, Huichuan; Nguyen Thi Thu, Thuy; He, Xiahong; Gravot, Antoine; Bernillon, Stéphane; Ballini, Elsa; Morel, Jean-Benoit

    2017-01-01

    Highlight  Modifications in glutamine synthetase OsGS1-2 expression and fungal pathogenicity underlie nitrogen-induced susceptibility to rice blast. Understanding why nitrogen fertilization increase the impact of many plant diseases is of major importance. The interaction between Magnaporthe oryzae and rice was used as a model for analyzing the molecular mechanisms underlying Nitrogen-Induced Susceptibility (NIS). We show that our experimental system in which nitrogen supply strongly affects rice blast susceptibility only slightly affects plant growth. In order to get insights into the mechanisms of NIS, we conducted a dual RNA-seq experiment on rice infected tissues under two nitrogen fertilization regimes. On the one hand, we show that enhanced susceptibility was visible despite an over-induction of defense gene expression by infection under high nitrogen regime. On the other hand, the fungus expressed to high levels effectors and pathogenicity-related genes in plants under high nitrogen regime. We propose that in plants supplied with elevated nitrogen fertilization, the observed enhanced induction of plant defense is over-passed by an increase in the expression of the fungal pathogenicity program, thus leading to enhanced susceptibility. Moreover, some rice genes implicated in nitrogen recycling were highly induced during NIS. We further demonstrate that the OsGS1-2 glutamine synthetase gene enhances plant resistance to M. oryzae and abolishes NIS and pinpoint glutamine as a potential key nutrient during NIS. PMID:28293247

  14. Vulnerability of boreal zone for increased nitrogen loading due to climate change

    Science.gov (United States)

    Rankinen, Katri; Holmberg, Maria

    2016-04-01

    The observed rapid warming of the boreal zone that has been observed in Finland (0.14 °C by decade) is expected to continue (http://www.ipcc.ch/report/ar5/wg1/). Also precipitation is assumed to increase in future. These changes may increase nitrogen (N) loading from terrestrial environments to water bodies by accelerating soil organic matter decay and by increasing runoff. Nitrogen is limiting nutrient in the Baltic Sea but also in some lakes, so increased loading may increase eutrophication. Further, high nitrate levels in drinking water may cause methaemoglobin anemia for humans, and nitrate is also connected to increased risk of diabetes and cancer. Thus EU has set upper limits to nitrate concentration in drinking water. MONIMET (LIFE12 ENV/FI/000409) is a project about Climate Change Indicators and Vulnerability of Boreal Zone. We simulated N loading from two boreal catchments to the receiving waters by the dynamic, catchment scale model INCA in different climate change and land use change scenarios. We calculated land use specific N loading values for these two well monitored catchments that belong to the LTER (The Long Term Ecological Research) monitoring network. We upscaled the results to the larger river basin, combining them with the information on drinking water supply to assess the vulnerability. Specific emphasis was paid on nitrate concentrations in soil water and groundwater. In general, land use change has higher influence on N loading than increase in precipitation and temperature alone. Peak runoff will sift from snow melting peak in April to late autumn and winter. Growing season will become longer allowing more efficient vegetation uptake of nutrients. Small groundwater aquifers and private wells in the middle of agricultural fields will be in the risk of increased N concentrations, if agricultural N loading increases due to changes in agricultural patterns and land use change.

  15. Dietary vitamin D3 deficiency alters intestinal mucosal defense and increases susceptibility to Citrobacter rodentium-induced colitis.

    Science.gov (United States)

    Ryz, Natasha R; Lochner, Arion; Bhullar, Kirandeep; Ma, Caixia; Huang, Tina; Bhinder, Ganive; Bosman, Else; Wu, Xiujuan; Innis, Sheila M; Jacobson, Kevan; Vallance, Bruce A

    2015-11-01

    Vitamin D deficiency affects more that 1 billion people worldwide. Although thought to increase risk of bacterial infections, the importance of vitamin D on host defense against intestinal bacterial pathogens is currently unclear since injection of the active form of vitamin D, 1,25(OH)2D3, increased susceptibility to the enteric bacterial pathogen Citrobacter rodentium by suppressing key immune/inflammatory factors. To further characterize the role of vitamin D during bacteria-induced colitis, we fed weanling mice either vitamin D3-deficient or vitamin D3-sufficient diets for 5 wk and then challenged them with C. rodentium. Vitamin D3-deficient mice lost significantly more body weight, carried higher C. rodentium burdens, and developed worsened histological damage. Vitamin D3-deficient mice also suffered greater bacterial translocation to extra-intestinal tissues, including mesenteric lymph nodes, spleen, and liver. Intestinal tissues of infected vitamin D3-deficient mice displayed increased inflammatory cell infiltrates as well as significantly higher gene transcript levels of inflammatory mediators TNF-α, IL-1β, IL-6, TGF-β, IL-17A, and IL-17F as well as the antimicrobial peptide REG3γ. Notably, these exaggerated inflammatory responses accelerated the loss of commensal microbes and were associated with an impaired ability to detoxify bacterial lipopolysaccharide. Overall, these studies show that dietary-induced vitamin D deficiency exacerbates intestinal inflammatory responses to infection, also impairing host defense.

  16. A facile approach towards increasing the nitrogen-content in nitrogen-doped carbon nanotubes via halogenated catalysts

    Science.gov (United States)

    Ombaka, L. M.; Ndungu, P. G.; Omondi, B.; McGettrick, J. D.; Davies, M. L.; Nyamori, V. O.

    2016-03-01

    Nitrogen-doped carbon nanotubes (N-CNTs) have been synthesized at 850 °C via a CVD deposition technique by use of three ferrocenyl derivative catalysts, i.e. para-CN, -CF3 and -Cl substituted-phenyl rings. The synthesized catalysts have been characterized by NMR, IR, HR-MS and XRD. The XRD analysis of the para-CF3 catalyst indicates that steric factors influence the X-ray structure of 1,1‧-ferrocenylphenyldiacrylonitriles. Acetonitrile or pyridine was used as carbon and nitrogen sources to yield mixtures of N-CNTs and carbon spheres (CS). The N-CNTs obtained from the para-CF3 catalysts, in pyridine, have the highest nitrogen-doping level, show a helical morphology and are less thermally stable compared with those synthesized by use of the para-CN and -Cl as catalyst. This suggests that fluorine heteroatoms enhance nitrogen-doping in N-CNTs and formation of helical-N-CNTs (H-N-CNTs). The para-CF3 and para-Cl catalysts in acetonitrile yielded iron-filled N-CNTs, indicating that halogens promote encapsulation of iron into the cavity of N-CNT. The use of acetonitrile, as carbon and nitrogen source, with the para-CN and -Cl as catalysts also yielded a mixture of N-CNTs and carbon nanofibres (CNFs), with less abundance of CNFs in the products obtained using para-Cl catalysts. However, para-CF3 catalyst in acetonitrile gave N-CNTs as the only shaped carbon nanomaterials.

  17. Ecosystem responses to warming-induced plant species loss and increased nitrogen availability in a Rocky Mountain subalpine meadow

    Science.gov (United States)

    Smith, Molly Elizabeth

    Climate change is predicted to be an important driver of future biodiversity changes, especially in mountainous environments. Climate warming-induced plant species loss is likely to be non-random and based on species-specific susceptibility to rising temperatures. Experimental warming results from a subalpine meadow in Colorado suggest that warming adversely affects shallow-rooted forb species in this ecosystem. To examine the ecological consequences of losing this warming-sensitive species group, I experimentally removed all shallow-rooted forb species from otherwise intact subalpine meadow plots. Since experimental warming also resulted in increased soil nitrogen availability, I crossed the removal treatment with a nitrogen addition treatment to determine whether the loss of shallow-rooted forbs altered the community's response to a perturbation in nitrogen availability. After three years of experimental species removal, tap-rooted forbs and grasses were able to fully compensate for the loss of shallow-rooted forbs with increased biomass production. Moreover, the remaining plant community yielded a larger biomass response to nitrogen addition when shallow-rooted forbs were removed, possibly because removal led to increased soil moisture. The loss of shallow-rooted forbs and addition of nitrogen did not have strong effects on nitrogen cycling beyond increases in the amount of nitrate moving down through the soil profile. Uptake of nitrogen into plant tissue was also not affected by either the shallow-rooted forb removal or nitrogen addition treatments, suggesting that nitrogen may not have been the most limiting resource during the experiment. I found that spatial heterogeneity generally had a greater influence on soil microbial community composition than any of the experimental treatments. I conclude that the warming-induced loss of shallow-rooted forbs did not affect biomass production, nitrogen cycling, or soil microbial community composition, but did increase

  18. Resting oxygen consumption and in vivo ADP are increased in myopathy due to complex I deficiency

    NARCIS (Netherlands)

    Roef, MJ; Reijngoud, DJ; Jeneson, JAL; Berger, R; de Meer, K

    2002-01-01

    Background: Patients with isolated complex I deficiency (CID) in skeletal muscle mitochondria often present with exercise intolerance as their major clinical symptom. Objective: To study the in vivo bioenergetics in patients with complex I deficiency in skeletal muscle mitochondria. Methods: In vivo

  19. Thymidine kinase 1 deficient cells show increased survival rate after UV-induced DNA damage

    DEFF Research Database (Denmark)

    Skovgaard, T; Rasmussen, Lene Juel; Munch-Petersen, Birgitte

    2010-01-01

    Balanced deoxynucleotide pools are known to be important for correct DNA repair, and deficiency for some of the central enzymes in deoxynucleotide metabolism can cause imbalanced pools, which in turn can lead to mutagenesis and cell death. Here we show that cells deficient for the thymidine salvage...

  20. Marginal Copper Deficiency Increases Liver Neutrophil Accumulation After Ischemia/Reperfusion in Rats

    Science.gov (United States)

    Copper deficiency can lead to an augmented inflammatory response through effects on both neutrophils and the microvascular endothelium. In the present study, we evaluated the effect of marginal copper deficiency on the inflammatory injury response to hepatic ischemia/reperfusion injury. Male weanlin...

  1. Increasing in-stream nitrogen concentrations under different bioenergy crop management practices in central Germany

    Science.gov (United States)

    Jomaa, Seifeddine; Thraen, Daniela; Rode, Michael

    2015-04-01

    Understanding how nitrogen fluxes respond to changes in land use and agriculture practices is crucial for improving instream water quality prediction. In central Germany, expansion of bioenergy crops such as maize and rape for ethanol production during the last decade led to increasing of fertilizer application rates. To examine the effect of these changes, surface water quality of a drinking water reservoir catchment was investigated for more than 30 years. The Weida catchment (99.5 km2) is part of the Elbe river basin and has a share of 67% agricultural land use with significant changes in agricultural practices within the investigation period. For the period 2004-2012, the share of maize and rape has been increased by 52% and 20%, respectively, for enhancing bioenergy production. To achieve our gaols, the semi-distributed hydrological water quality HYPE (Hydrological Predictions for the Environment) model was calibrated for discharge and inorganic nitrogen concentrations (IN) during the period 1997-2000.The model was validated successfully (with lowest performance of NSE = 0.78 and PBIAS = 3.74% for discharge) for three different periods 1983-1987, 1989-1996 and 2000-2003, which are charaterized by different fertilizer application rates. Results showed that the HYPE model reproduced reasonably well discharge and IN daily loads (with lowest NSE = 0.64 for IN-load). In addition, the HYPE model was evaluated successfully to predict the discharge and IN concentrations for the period 2004-2012, where detailed input data in terms of crops management (field-specific survey) have been considered. Land use and crop rotations scenarios, with high hypothetical percentage of acceptance by the farmers, revealed that continuous conversion of agricultural land into bioenergy crops, will most likely, lead to an enrichment of in-stream nitrogen, especially after spring storms.

  2. Increased visceral adiposity and cortisol to cortisone ratio in adults with congenital lifetime isolated GH deficiency.

    Science.gov (United States)

    Gomes-Santos, Elenilde; Salvatori, Roberto; Ferrão, Thiago O; Oliveira, Carla R P; Diniz, Rachel D C A; Santana, João A M; Pereira, Francisco A; Barbosa, Rita A A; Souza, Anita H O; Melo, Enaldo V; Epitácio-Pereira, Carlos C; Oliveira-Santos, Alécia A; Oliveira, Ingrid A S; Machado, Julianne A; Santana-Júnior, Francisco J; Barreto-Filho, José A S; Aguiar-Oliveira, Manuel H

    2014-09-01

    Adult-onset GH deficiency (GHD) increases visceral adiposity and the activity of the enzyme 11β-hydroxysteroid dehydrogenase, which converts cortisone (E) to cortisol (F), both linked to insulin resistance and increased cardiovascular risk. Conversely, we reported that adults with congenital isolated GHD (IGHD) have increased insulin sensitivity. To assess the type of fat distribution and the amount of visceral and sc fat and to correlate them to the F/E ratio in adults with untreated IGHD due to a mutation in the GHRH receptor gene. Body composition was assessed by dual-energy x-ray absorptiometry, thickness of sc and visceral fat was measured by sonography, and serum F and E were measured in 23 IGHD subjects and 21 age-matched controls. Waist/hip ratio (WHR), trunk fat, and trunk/extremity fat (TR/EXT) ratio were higher in IGHD subjects. Visceral fat index (VFI) (but not sc fat index [SFI]) was higher in IGHD. F and F/E ratio were also higher in IGHD. In all 44 individuals, WHR correlated with TR/EXT ratio, thickness of visceral fat, VFI/SFI ratio, F, and F/E ratio. TR/EXT ratio correlated with visceral fat thickness, VFI/SFI ratio, and F. Age had a significant effect on VFI and on F/E ratio. Body mass index SD score and WHR have a similar significant effect on TR/EXT ratio and on F/E ratio. Lifetime congenital untreated IGHD causes increased visceral adiposity with a high F/E ratio. However, the increased insulin sensitivity suggests that visceral adiposity needs a minimal GH secretion to translate into increased insulin resistance.

  3. Mice deficient in Sfrp1 exhibit increased adiposity, dysregulated glucose metabolism, and enhanced macrophage infiltration.

    Directory of Open Access Journals (Sweden)

    Kelly J Gauger

    Full Text Available The molecular mechanisms involved in the development of obesity and related complications remain unclear. Wnt signaling plays an important role in preadipocyte differentiation and adipogenesis. The expression of a Wnt antagonist, secreted frizzled related protein 1 (SFRP1, is increased in response to initial weight gain, then levels are reduced under conditions of extreme obesity in both humans and animals. Here we report that loss of Sfrp1 exacerbates weight gain, glucose homeostasis and inflammation in mice in response to diet induced obesity (DIO. Sfrp1(-/- mice fed a high fat diet (HFD exhibited an increase in body mass accompanied by increases in body fat percentage, visceral white adipose tissue (WAT mass, and adipocyte size. Moreover, Sfrp1 deficiency increases the mRNA levels of key de novo lipid synthesis genes (Fasn, Acaca, Acly, Elovl, Scd1 and the transcription factors that regulate their expression (Lxr-α, Srebp1, Chreb, and Nr1h3 in WAT. Fasting glucose levels are elevated, glucose clearance is impaired, hepatic gluconeogenesis regulators are aberrantly upregulated (G6pc and Pck1, and glucose transporters are repressed (Slc2a2 and Slc2a4 in Sfrp1(-/- mice fed a HFD. Additionally, we observed increased steatosis in the livers of Sfrp1(-/- mice. When there is an expansion of adipose tissue there is a sustained inflammatory response accompanied by adipokine dysregulation, which leads to chronic subclinical inflammation. Thus, we assessed the inflammatory state of different tissues and revealed that Sfrp1(-/- mice fed a HFD exhibited increased macrophage infiltration and expression of pro-inflammatory markers including IL-6, Nmnat, Tgf-β2, and SerpinE1. Our findings demonstrate that the expression of Sfrp1 is a critical factor required for maintaining appropriate cellular signaling in response to the onset of obesity.

  4. Resistance of essential fatty acid-deficient rats to endotoxin-induced increases in vascular permeability

    Energy Technology Data Exchange (ETDEWEB)

    Li, E.J.; Cook, J.A.; Spicer, K.M.; Wise, W.C.; Rokach, J.; Halushka, P.V. (Medical Univ. of South Carolina, Charleston (USA))

    1990-06-01

    Resistance to endotoxin in essential fatty acid-deficient (EFAD) rats is associated with reduced synthesis of certain arachidonic acid metabolites. It was hypothesized that EFAD rats would manifest decreased vascular permeability changes during endotoxemia as a consequence of reduced arachidonic acid metabolism. To test this hypothesis, changes in hematocrit (HCT) and mesenteric localization rate of technetium-labeled human serum albumin (99mTc-HSA) and red blood cells (99mTc-RBC) were assessed in EFAD and normal rats using gamma-camera imaging. Thirty minutes after Salmonella enteritidis endotoxin, EFAD rats exhibited less hemoconcentration as determined by % HCT than normal rats. Endotoxin caused a less severe change in permeability index in the splanchnic region in EFAD rats than in normal rats (1.2 +/- 0.6 x 10(-3)min-1 vs. 4.9 +/- 1.7 x 10(-3)min-1 respectively, P less than 0.05). In contrast to 99mTc-HSA, mesenteric localization of 99mTc-RBC was not changed by endotoxin in control or EFAD rats. Supplementation with ethyl-arachidonic acid did not enhance susceptibility of EFAD rats to endotoxin-induced splanchnic permeability to 99mTc-HSA. Leukotrienes have been implicated as mediators of increased vascular permeability in endotoxin shock. Since LTC3 formation has been reported to be increased in EFA deficiency, we hypothesized that LTC3 may be less potent than LTC4. Thus the effect of LTC3 on mean arterial pressure and permeability was compared to LTC4 in normal rats. LTC3-induced increases in peak mean arterial pressure were less than LTC4 at 10 micrograms/kg (39 +/- 5 mm Hg vs. 58 +/- 4 mm Hg respectively, P less than 0.05) and at 20 micrograms/kg (56 +/- 4 mm Hg vs. 75 +/- 2 mm Hg respectively, P less than 0.05). LY171883 (30 mg/kg), an LTD4/E4 receptor antagonist, attenuated the pressor effect of LTC4, LTD4, and LTC3.

  5. Vitamin B6 deficient plants display increased sensitivity to high light and photo-oxidative stress

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    Rumeau Dominique

    2009-11-01

    Full Text Available Abstract Background Vitamin B6 is a collective term for a group of six interconvertible compounds: pyridoxine, pyridoxal, pyridoxamine and their phosphorylated derivatives. Vitamin B6 plays essential roles as a cofactor in a range of biochemical reactions. In addition, vitamin B6 is able to quench reactive oxygen species in vitro, and exogenously applied vitamin B6 protects plant cells against cell death induced by singlet oxygen (1O2. These results raise the important question as to whether plants employ vitamin B6 as an antioxidant to protect themselves against reactive oxygen species. Results The pdx1.3 mutation affects the vitamin B6 biosynthesis enzyme, pyridoxal synthase (PDX1, and leads to a reduction of the vitamin B6 concentration in Arabidopsis thaliana leaves. Although leaves of the pdx1.3 Arabidopsis mutant contained less chlorophyll than wild-type leaves, we found that vitamin B6 deficiency did not significantly impact photosynthetic performance or shoot and root growth. Chlorophyll loss was associated with an increase in the chlorophyll a/b ratio and a selective decrease in the abundance of several PSII antenna proteins (Lhcb1/2, Lhcb6. These changes were strongly dependent on light intensity, with high light amplifying the difference between pdx1.3 and the wild type. When leaf discs were exposed to exogenous 1O2, lipid peroxidation in pdx1.3 was increased relative to the wild type; this effect was not observed with superoxide or hydrogen peroxide. When leaf discs or whole plants were exposed to excess light energy, 1O2-mediated lipid peroxidation was enhanced in leaves of the pdx1.3 mutant relative to the wild type. High light also caused an increased level of 1O2 in vitamin B6-deficient leaves. Combining the pdx1.3 mutation with mutations affecting the level of 'classical' quenchers of 1O2 (zeaxanthin, tocopherols resulted in a highly photosensitive phenotype. Conclusion This study demonstrates that vitamin B6 has a function in

  6. Testosterone Deficiency Increases Hospital Readmission and Mortality Rates in Male Patients with Heart Failure

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Marcelo Rodrigues dos; Sayegh, Ana Luiza Carrari; Groehs, Raphaela Vilar Ramalho; Fonseca, Guilherme [Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo (Brazil); Trombetta, Ivani Credidio [Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo (Brazil); Universidade Nove de Julho (UNINOVE) (Brazil); Barretto, Antônio Carlos Pereira [Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo (Brazil); Arap, Marco Antônio [Faculdade de medicina da Universidade de São Paulo - Urologia (Brazil); Negrão, Carlos Eduardo [Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo (Brazil); Escola de Educação Física e Esporte da Universidade de São Paulo, São Paulo, SP (Brazil); Middlekauff, Holly R. [Division of Cardiology - David Geffen School of Medicine - University of California (United States); Alves, Maria-Janieire de Nazaré Nunes, E-mail: janieire.alves@incor.usp.br [Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo (Brazil)

    2015-09-15

    Testosterone deficiency in patients with heart failure (HF) is associated with decreased exercise capacity and mortality; however, its impact on hospital readmission rate is uncertain. Furthermore, the relationship between testosterone deficiency and sympathetic activation is unknown. We investigated the role of testosterone level on hospital readmission and mortality rates as well as sympathetic nerve activity in patients with HF. Total testosterone (TT) and free testosterone (FT) were measured in 110 hospitalized male patients with a left ventricular ejection fraction < 45% and New York Heart Association classification IV. The patients were placed into low testosterone (LT; n = 66) and normal testosterone (NT; n = 44) groups. Hypogonadism was defined as TT < 300 ng/dL and FT < 131 pmol/L. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography in a subpopulation of 27 patients. Length of hospital stay was longer in the LT group compared to in the NT group (37 ± 4 vs. 25 ± 4 days; p = 0.008). Similarly, the cumulative hazard of readmission within 1 year was greater in the LT group compared to in the NT group (44% vs. 22%, p = 0.001). In the single-predictor analysis, TT (hazard ratio [HR], 2.77; 95% confidence interval [CI], 1.58–4.85; p = 0.02) predicted hospital readmission within 90 days. In addition, TT (HR, 4.65; 95% CI, 2.67–8.10; p = 0.009) and readmission within 90 days (HR, 3.27; 95% CI, 1.23–8.69; p = 0.02) predicted increased mortality. Neurohumoral activation, as estimated by MSNA, was significantly higher in the LT group compared to in the NT group (65 ± 3 vs. 51 ± 4 bursts/100 heart beats; p < 0.001). These results support the concept that LT is an independent risk factor for hospital readmission within 90 days and increased mortality in patients with HF. Furthermore, increased MSNA was observed in patients with LT.

  7. Testosterone Deficiency Increases Hospital Readmission and Mortality Rates in Male Patients with Heart Failure

    Directory of Open Access Journals (Sweden)

    Marcelo Rodrigues dos Santos

    2015-01-01

    Full Text Available Background: Testosterone deficiency in patients with heart failure (HF is associated with decreased exercise capacity and mortality; however, its impact on hospital readmission rate is uncertain. Furthermore, the relationship between testosterone deficiency and sympathetic activation is unknown. Objective: We investigated the role of testosterone level on hospital readmission and mortality rates as well as sympathetic nerve activity in patients with HF. Methods: Total testosterone (TT and free testosterone (FT were measured in 110 hospitalized male patients with a left ventricular ejection fraction < 45% and New York Heart Association classification IV. The patients were placed into low testosterone (LT; n = 66 and normal testosterone (NT; n = 44 groups. Hypogonadism was defined as TT < 300 ng/dL and FT < 131 pmol/L. Muscle sympathetic nerve activity (MSNA was recorded by microneurography in a subpopulation of 27 patients. Results: Length of hospital stay was longer in the LT group compared to in the NT group (37 ± 4 vs. 25 ± 4 days; p = 0.008. Similarly, the cumulative hazard of readmission within 1 year was greater in the LT group compared to in the NT group (44% vs. 22%, p = 0.001. In the single-predictor analysis, TT (hazard ratio [HR], 2.77; 95% confidence interval [CI], 1.58–4.85; p = 0.02 predicted hospital readmission within 90 days. In addition, TT (HR, 4.65; 95% CI, 2.67–8.10; p = 0.009 and readmission within 90 days (HR, 3.27; 95% CI, 1.23–8.69; p = 0.02 predicted increased mortality. Neurohumoral activation, as estimated by MSNA, was significantly higher in the LT group compared to in the NT group (65 ± 3 vs. 51 ± 4 bursts/100 heart beats; p < 0.001. Conclusion: These results support the concept that LT is an independent risk factor for hospital readmission within 90 days and increased mortality in patients with HF. Furthermore, increased MSNA was observed in patients with LT.

  8. Deficiency of the Angiotensinase Aminopeptidase A Increases Susceptibility to Glomerular Injury.

    Science.gov (United States)

    Velez, Juan Carlos Q; Arif, Ehtesham; Rodgers, Jessalyn; Hicks, Megan P; Arthur, John M; Nihalani, Deepak; Bruner, Evelyn T; Budisavljevic, Milos N; Atkinson, Carl; Fitzgibbon, Wayne R; Janech, Michael G

    2017-07-01

    Aminopeptidase A (APA) is expressed in glomerular podocytes and tubular epithelia and metabolizes angiotensin II (AngII), a peptide known to promote glomerulosclerosis. In this study, we tested whether APA expression changes in response to progressive nephron loss or whether APA exerts a protective role against glomerular damage and during AngII-mediated hypertensive kidney injury. At advanced stages of FSGS, fawn-hooded hypertensive rat kidneys exhibited distinctly increased APA staining in areas of intact glomerular capillary loops. Moreover, BALB/c APA-knockout (KO) mice injected with a nephrotoxic serum showed persistent glomerular hyalinosis and albuminuria 96 hours after injection, whereas wild-type controls achieved virtually full recovery. We then tested the effect of 4-week infusion of AngII (400 ng/kg per minute) in APA-KO and wild-type mice. Although we observed no significant difference in achieved systolic BP, AngII-treated APA-KO mice developed a significant rise in albuminuria not observed in AngII-treated wild-type mice along with increased segmental and global sclerosis and/or collapse of juxtamedullary glomeruli, microcystic tubular dilation, and tubulointerstitial fibrosis. In parallel, AngII treatment significantly increased the kidney AngII content and attenuated the expression of podocyte nephrin in APA-KO mice but not in wild-type controls. These data show that deficiency of APA increases susceptibility to glomerular injury in BALB/c mice. The augmented AngII-mediated kidney injury observed in association with increased intrarenal AngII accumulation in the absence of APA suggests a protective metabolizing role of APA in AngII-mediated glomerular diseases. Copyright © 2017 by the American Society of Nephrology.

  9. Loss of Cell Adhesion Increases Tumorigenic Potential of Polarity Deficient Scribble Mutant Cells.

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    Indrayani Waghmare

    Full Text Available Epithelial polarity genes are important for maintaining tissue architecture, and regulating growth. The Drosophila neoplastic tumor suppressor gene scribble (scrib belongs to the basolateral polarity complex. Loss of scrib results in disruption of its growth regulatory functions, and downregulation or mislocalization of Scrib is correlated to tumor growth. Somatic scribble mutant cells (scrib- surrounded by wild-type cells undergo apoptosis, which can be prevented by introduction of secondary mutations that provide a growth advantage. Using genetic tools in Drosophila, we analyzed the phenotypic effects of loss of scrib in different growth promoting backgrounds. We investigated if a central mechanism that regulates cell adhesion governs the growth and invasive potential of scrib mutant cells. Here we show that increased proliferation, and survival abilities of scrib- cells in different genetic backgrounds affect their differentiation, and intercellular adhesion. Further, loss of scrib is sufficient to cause reduced cell survival, activation of the JNK pathway and a mild reduction of cell adhesion. Our data show that for scrib cells to induce aggressive tumor growth characterized by loss of differentiation, cell adhesion, increased proliferation and invasion, cooperative interactions that derail signaling pathways play an essential role in the mechanisms leading to tumorigenesis. Thus, our study provides new insights on the effects of loss of scrib and the modification of these effects via cooperative interactions that enhance the overall tumorigenic potential of scrib deficient cells.

  10. IL-4 Deficiency Decreases Mortality but Increases Severity of Arthritis in Experimental Group B Streptococcus Infection

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    Luciana Tissi

    2009-01-01

    Full Text Available IL-4 is an anti-inflammatory cytokine that inhibits the onset and severity in different experimental arthritis models. Group B streptococci (GBS have been recognized as an ever-growing cause of serious invasive infections in nonpregnant adults. Septic arthritis is a clinical manifestation of GBS infection. To investigate the role of IL-4 in experimental GBS infection, IL-4 deficient or competent mice were inoculated with 1×107 GBS/mouse. Mortality, appearance of arthritis, GBS growth in the organs, and local and systemic cytokine and chemokine production were examined. IL-4–/– mice showed lower mortality rates but increased severity of arthritis and exhibited a lower microbial load in blood, kidneys, and joints than wt mice. Increased local levels of IL-1 β, IL-6, TNF-α, MIP-1α, and MIP-2 accompanied the more severe arthritis in IL-4–/– mice. Our results suggest a detrimental role of IL-4 in GBS sepsis, whereas it plays a beneficial effect on GBS-induced arthritis.

  11. Growth Promotion, Increase of Iron, Potassium and Cell Wall Components following Silicon Application in Rice under Iron Deficiency

    Directory of Open Access Journals (Sweden)

    z Kiani Chalmardi

    2014-07-01

    Full Text Available Iron deficiency is one of the most important stress reducing crop growth and yields. Silicon is also an essential element in most grasses including rice that may reduces biotic and abiotic stresses. In present study, the interactions of silicon and iron nutrition were studied in rice (Oryza sativa L. cv. Tarem. The plants cultivated in greenhouse under iron treatments of 0, 2 and 10 mg l-1 as a Fe-EDTA (first factor and silicon treatments of 0 and 1.5 mM sodium silicate (second factor. The experimental design was completely randomized blocks as a factorial experiment. The plants were harvested after 5 weeks. Iron deficiency resulted in reduction of dry mater and height of plants. In addition, cellulose content in shoots and lignin and soluble proteins in roots and shoots decreased, however, potassium content in roots increased due to iron deficiency. On the contrary, silicon application caused significant increase in dry mater and height of plants. Besides, iron and potassium contents increased in iron deficient plants following silicon application. Also, cellulose, lignin, and soluble proteins in roots and shoots and phenolic compounds in shoots enhanced in silicon fed plants. The results indicated that silicon nutrition could ameliorate harmful effects of iron deficiency by increase of iron and potassium contents and increment of cell wall components and phenolic compounds

  12. Increases in duodenal glutamic acid supply linearly increase small intestinal starch digestion but not nitrogen balance in cattle.

    Science.gov (United States)

    Blom, E J; Anderson, D E; Brake, D W

    2016-12-01

    Small intestinal starch digestion (SISD) in cattle is often limited; however, greater postruminal flow of high-quality protein (e.g., casein) can increase SISD, and Glu can mimic responses to casein for SISD. We evaluated effects of increasing Glu flows to the duodenum on SISD and N retention in cattle. Cattle received (DM basis) continuous duodenal infusion of raw cornstarch (1.5 ± 0.08 kg/d) and 0, 30.9 ± 0.6, 62.4 ± 1.2, or 120.4 ± 3.4 g/d Glu or 387.9 ± 17.5 g/d casein. As expected, the positive control (i.e., casein) increased ( = 0.05) SISD. Interestingly, SISD linearly increased ( = 0.02) with increasing amounts of Glu. Starch flow to the ileum linearly decreased ( = 0.04) in response to greater postruminal Glu and tended to decrease ( = 0.07) with duodenal casein infusion. Ileal flow of ethanol-soluble starch was not affected by duodenal Glu ( = 0.16) or casein ( = 0.42). There was a tendency ( = 0.08) for a quadratic response to Glu for ileal glucose flow with greater flows for intermediate levels of Glu, but casein had no effect ( = 0.81) on glucose flows to the ileum. Greater postruminal supplies of Glu (linear, = 0.05) and casein ( = 0.02) decreased fecal starch flow. Postruminal starch digestion was increased by both casein ( = 0.03) and Glu (linear, = 0.05). Nitrogen intake from feed was not different among treatments ( ≥ 0.23). By design, infusate N increased from 0 to 13 ± 1.5 g/d with greater amounts of Glu, and casein provided 61 ± 1.3 g N/d. Urinary N excretion was not affected ( ≥ 0.30) by postruminal Glu flow, but urine N was increased by casein ( Glutamic acid did not affect N retention ( ≥ 0.34), but casein increased N retention ( < 0.01). However, N retained as a percent of N intake (26.7 ± 1.7%) was not different when cattle were provided Glu ( ≥ 0.16) or casein ( = 0.38).

  13. Increased heart rate variability but normal resting metabolic rate in hypocretin/orexin-deficient human narcolepsy.

    NARCIS (Netherlands)

    Fronczek, R.; Overeem, S.; Reijntjes, R.; Lammers, G.J.; Dijk, J.G.M.; Pijl, H.

    2008-01-01

    STUDY OBJECTIVES: We investigated autonomic balance and resting metabolic rate to explore their possible involvement in obesity in hypocretin/orexin-deficient narcoleptic subjects. METHODS: Resting metabolic rate (using indirect calorimetry) and variability in heart rate and blood pressure were

  14. Vitamin D Deficiency and Increased Risk of Bladder Carcinoma: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    2015-11-01

    Full Text Available Background/Aims: Vitamin D status in relation to bladder carcinoma risk was still inconsistent. This study was carried out to evaluate the relationship between vitamin D status and bladder carcinoma risk through a meta-analysis approach. Methods: Pubmed, Web of Science, CNKI, and Embase were searched systemically to find eligible studies from the earliest available date to April 16, 2015. The search terms “vitamin D”, “25-hydroxyvitamin D”, “bladder cancer” or “bladder carcinoma” were used to retrieve relevant studies. The exposure of interest was intake of vitamin D or serum vitamin D levels, and the outcome of interest was bladder carcinoma incidence or mortality. The pooled risk ratio (RR values and their 95%CIs were calculated through meta-analysis. Results: Seven studies with a total of 62,141 participants met the inclusion criteria and were finally included into the meta-analysis. There was no heterogeneity among those included studies (I2 = 0%, P = 0.53. The pooled RR of bladder carcinoma for the lowest category versus the highest category of vitamin D was 1.34 (95% CI 1.17-1.53, P Conclusion: Vitamin D deficiency is associated with increased risk of bladder carcinoma in present study.

  15. Bax-deficiency prolongs cerebellar neurogenesis, accelerates medulloblastoma formation and paradoxically increases both malignancy and differentiation

    Science.gov (United States)

    Garcia, Idoia; Crowther, Andrew J.; Gama, Vivian; Miller, C. Ryan; Deshmukh, Mohanish; Gershon, Timothy R.

    2012-01-01

    Neurogenesis requires negative regulation through differentiation of progenitors or their programmed cell death (PCD). Growth regulation is particularly important in the postnatal cerebellum, where excessive progenitor proliferation promotes medulloblastoma, the most common malignant brain tumor in children. We present evidence that PCD operates alongside differentiation to regulate cerebellar granule neuron progenitors (CGNPs) and to prevent medulloblastoma. Here we show that genetic deletion of pro-apoptotic Bax disrupts regulation of cerebellar neurogenesis and promotes medulloblastoma formation. In Bax−/− mice, the period of neurogenesis was extended into the third week of postnatal life, and ectopic neurons and progenitors collected in the molecular layer of the cerebellum and adjacent tectum. Importantly, genetic deletion of Bax in medulloblastoma-prone ND2:SmoA1 transgenic mice greatly accelerated tumorigenesis. Bax-deficient medulloblastomas exhibited strikingly distinct pathology, with reduced apoptosis, increased neural differentiation and tectal migration. Comparing Bax+/+ and Bax−/− medulloblastomas, we were able to identify up-regulation of Bcl-2 and nuclear exclusion of p27 as tumorigenic changes that are required to mitigate the tumor suppressive effect of Bax. Studies on human tumors confirmed the importance of modulating Bax in medulloblastoma pathogenesis. Our results demonstrate that Bax-dependent apoptosis regulates postnatal cerebellar neurogenesis, suppresses medulloblastoma formation, and imposes selective pressure on tumors that form. Functional resistance to Bax-mediated apoptosis, required for medulloblastoma tumorigenesis, may be a tumor-specific vulnerability to be exploited for therapeutic benefit. PMID:22710714

  16. Increased susceptibility to diet-induced obesity in histamine-deficient mice

    DEFF Research Database (Denmark)

    Jørgensen, Emilie A; Vogelsang, Thomas W; Knigge, Ulrich

    2006-01-01

    BACKGROUND AND AIM: The neurotransmitter histamine is involved in the regulation of appetite and in the development of age-related obesity in mice. Furthermore, histamine is a mediator of the anorexigenic action of leptin. The aim of the present study was to investigate a possible role of histamine...... in the development of high-fat diet (HFD)-induced obesity. METHODS: Histamine-deficient histidine decarboxylase knock-out (HDC-KO) mice and C57BL/6J wild-type (WT) mice were given either a standard diet (STD) or HFD for 8 weeks. Body weight, 24-hour caloric intake, epididymal adipose tissue size, plasma leptin...... concentration and quantitative expression of leptin receptor (Ob-R) mRNA were measured. RESULTS: Both HDC-KO and WT mice fed an HFD for 8 weeks increased their body weight significantly more than STD-fed mice. A significant difference in body weight gain between HDC-KO mice fed an HFD or an STD was seen after 2...

  17. Over-expression of OsPTR6 in rice increased plant growth at different nitrogen supplies but decreased nitrogen use efficiency at high ammonium supply.

    Science.gov (United States)

    Fan, Xiaorong; Xie, Dan; Chen, Jingguang; Lu, Haiyan; Xu, Yanling; Ma, Cui; Xu, Guohua

    2014-10-01

    Nitrogen (N) plays a critical role in plant growth and productivity and PTR/NRT1 transporters are critical for rice growth. In this study, OsPTR6, a PTR/NRT1 transporter, was over-expressed in the Nipponbare rice cultivar by Agrobacterium tumefaciens transformation using the ubiquitin (Ubi) promoter. Three single-copy T2 generation transgenic lines, named OE1, OE5 and OE6, were produced and subjected to hydroponic growth experiments in different nitrogen treatments. The results showed the plant height and biomass of the over-expression lines were increased, and plant N accumulation and glutamine synthetase (GS) activities were enhanced at 5.0mmol/L NH4(+) and 2.5mmol/L NH4NO3. The expression of OsATM1 genes in over-expression lines showed that the OsPTR6 over expression increased OsAMT1.1, OsATM1.2 and OsAMT1.3 expression at 0.2 and 5.0mmol/L NH4(+) and 2.5mmol/L NH4NO3. However, nitrogen utilisation efficiency (NUE) was decreased at 5.0mmol/LNH4(+). These data suggest that over-expression of the OsPTR6 gene could increase rice growth through increasing ammonium transporter expression and glutamine synthetase activity (GSA), but decreases nitrogen use efficiency under conditions of high ammonium supply.

  18. In Winter Wheat, No-Till Increases Mycorrhizal Colonization thus Reducing the Need for Nitrogen Fertilization

    Directory of Open Access Journals (Sweden)

    Julien Verzeaux

    2016-06-01

    Full Text Available Arbuscular mycorrhizal fungi (AMF play a major role in the uptake of nutrients by agricultural plants. Nevertheless, some agricultural practices can interrupt fungal-plant signaling and thus impede the establishment of the mycorrhizal symbiosis. A field experiment performed over a 5-year period demonstrated that both the absence of tillage and of nitrogen (N fertilization improved AMF colonization of wheat roots. Moreover, under no-till conditions, N uptake and aboveground biomass production did not vary significantly between N-fertilized and N-unfertilized plots. In contrast, both N uptake and above ground biomass were much lower when N fertilizer was not added during conventional tillage. This finding strongly suggests that for wheat, no-till farming is a sustainable agricultural system that allows a gradual reduction in N fertilizer use by promoting AMF functionality and at the same time increasing N uptake.

  19. Carriers of 21-hydroxylase deficiency are not at increased risk for hyperandrogenism.

    Science.gov (United States)

    Knochenhauer, E S; Cortet-Rudelli, C; Cunnigham, R D; Conway-Myers, B A; Dewailly, D; Azziz, R

    1997-02-01

    A deficiency of 21-hydroxylase activity is one of the most commonly inherited genetic disorders in man, with heterozygosity for CYP21 mutations affecting approximately 1 in 60 of the non-Jewish Caucasian population. We have hypothesized that heterozygosity for CYP21 mutations in women increases their risk of developing clinically evident hyperandrogenism, and that this risk is related to the severity of the mutation of CYP21 and/or the 17-hydroxyprogesterone (17-OHP) response to ACTH stimulation. To test these hypotheses, we studied 38 obligate carriers for 21-hydroxylase deficiency (i.e. mothers of children with congenital adrenal hyperplasia or nonclassic congenital adreanl hyperplasia), comparing them to 27 weight-, parity-, and age-matched controls. Premenopausal carriers, not receiving hormonal treatment (n = 27), had higher mean total and free testosterone [T; 2.02 +/- 0.55 vs. 1.56 +/- 0.65 nmol/L (P < 0.007) and 0.018 +/- 0.007 vs. 0.012 +/- 0.006 nmol/L (P < 0.007), respectively] and lower mean sex hormone-binding globulin (214 +/- 62 vs. 277 +/- 129 nmol/L; P < 0.03) levels compared to controls. There was no difference in the mean basal levels of dehydroepiandrosterone sulfate, androstenedione (A4), or 17-OHP between carriers and controls. As expected, carriers exhibited higher stimulated and net increment 17-OHP levels than controls [21.1 +/- 27.1 vs. 6.2 +/- 3.1 nmol/L (P < 0.01) and 19.0 +/- 26.5 vs. 4.4 +/- 2.8 nmol/L (P < 0.009), respectively]. However, no difference was observed in the response of A4 to ACTH-(1-24) stimulation. Of the 27 carriers studied biochemically, 2 (7.4%) had a stimulated 17-OHP value between 30.3-60.6 nmol/L, and 1 (3.7%) had a 17-OHP level above 60.6 nmol/L, suggestive of nonclassic adrenal hyperplasia. Of all carriers studied genetically (n = 36), 50.0% (18 of 36) had 1, 33% (12 of 36) had 2, and 16.7% (6 of 36) had 3 or more mutations. In 27.8% (10 of 36) of carriers, the mutations were contiguous, consistent with a large

  20. PTP1B deficiency increases glucose uptake in neonatal hepatocytes: involvement of IRA/GLUT2 complexes.

    Science.gov (United States)

    González-Rodriguez, Agueda; Nevado, Carmen; Escrivá, Fernando; Sesti, Giorgio; Rondinone, Cristina M; Benito, Manuel; Valverde, Angela M

    2008-08-01

    The contribution of the liver to glucose utilization is essential to maintain glucose homeostasis. Previous data from protein tyrosine phosphatase (PTP) 1B-deficient mice demonstrated that the liver is a major site for PTP1B action in the periphery. In this study, we have investigated the consequences of PTP1B deficiency in glucose uptake in hepatocytes from neonatal and adult mice. The lack of PTP1B increased basal glucose uptake in hepatocytes from neonatal (3-5 days old) but not adult (10-12 wk old) mice. This occurs without changes in hexokinase, glucokinase, and glucose 6-phosphatase enzymatic activities. By contrast, the glucose transporter GLUT2 was upregulated at the protein level in neonatal hepatocytes and livers from PTP1B-deficient neonates. These results were accompanied by a significant increase in the net free intrahepatic glucose levels in the livers of PTP1B(-/-) neonates. The association between GLUT2 and insulin receptor (IR) A isoform was increased in PTP1B(-/-) neonatal hepatocytes compared with the wild-type. Indeed, PTP1B deficiency in neonatal hepatocytes shifted the ratio of isoforms A and B of the IR by increasing the amount of IRA and decreasing IRB. Moreover, overexpression of IRA in PTP1B(-/-) neonatal hepatocytes increased the amount of IRA/GLUT2 complexes. Conversely, hepatocytes from adult mice only expressed IRB. Since IRA plays a direct role in the regulation of glucose uptake in neonatal hepatocytes through its specific association with GLUT2, we propose the increase in IRA/GLUT2 complexes due to PTP1B deficiency as the molecular mechanism of the increased glucose uptake in the neonatal stage.

  1. Increased Life Span due to Calorie Restriction in Respiratory-Deficient Yeast.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available A model for replicative life span extension by calorie restriction (CR in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD-dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1 demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2 show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3 suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742.

  2. Increased susceptibility to experimental steatohepatitis induced by methionine-choline deficiency in HBs-Tg mice

    Institute of Scientific and Technical Information of China (English)

    Miao-MiaoFu; RuiSun; Zhi-GangTian; Hai-MingWei

    2010-01-01

    BACKGROUND: Worldwide, about 25% of individuals with chronic hepatitis B have fatty liver disease. Lipogenic diets that are completely devoid of methionine and choline induce nonalcoholic fatty liver disease. However, no animal model of nonalcoholic steatohepatitis associated with HBV infection is available, and the influence of viral infection on nutritional hepatic steatosis is unclear. METHODS: We used HBV surface antigen transgenic mice (HBs-Tg mice), which mimic healthy human carriers with hepatitis B surface antigen. The mice were fed with a high-fat methionine-choline-deficient diet (MCD) to build a reliable rodent nutritional model of nonalcoholic steatohepatitis associated with HBV infection, and the changes in body weight and serum triglycerides were measured. Hepatocyte ballooning changes were determined by hematoxylin and eosin staining. The extent of hepatic fat accumulation was evaluated by oil red O staining. Immunohistochemical assays were performed to detect proliferating cell nuclear antigen as an index of cell proliferation. RESULTS: MCD feeding provoked systemic weight loss and liver injury. MCD feeding caused more macrovesicular fat droplets and fat accumulation in the livers of HBs-Tg mice than in wild-type C57BL/6 mice. In addition, within 30 days of MCD exposure, more PCNA-positive nuclei were found in the livers of HBs-Tg mice. CONCLUSIONS: HBs-Tg mice fed with a lipogenic MCD form more macrovesicular fat droplets earlier, coincident with more hepatocyte proliferation, resulting in the appearance of increased susceptibility to experimental steatohepatitis in these mice.

  3. Foliar Spray of Nitrogen Fertilizer on Raised Bed Increases Yield of Transplanted Aman Rice over Conventional Method

    OpenAIRE

    M. H. M. Bhuyan; Mst. R. Ferdousi; Iqbal, M. T.

    2012-01-01

    Bed planting with foliar nitrogen fertilizer application of rice production systems is very new, and research on it is still at introductory phase. Influence of foliar application of nitrogen fertilizer on growth and yield of transplanted aman rice and evaluation of water and fertilizer application efficiency of rice-fallow-rice cropping system were investigated under raised bed cultivation method. Results showed that foliar spray in bed planting method increased grain yield of transplanted a...

  4. Subclinical vitamin D deficiency is increased in adolescent girls who wear concealing clothing.

    Science.gov (United States)

    Hatun, Sukru; Islam, Omer; Cizmecioglu, Filiz; Kara, Bulent; Babaoglu, Kadir; Berk, Fatma; Gökalp, Ayse Sevim

    2005-02-01

    Vitamin D deficiency continues to be a worldwide problem, especially in developing countries. The aim of this study was to investigate potential risk factors for vitamin D deficiency. Girls (n = 89) aged 13 to 17 y were enrolled in the study. Study subjects were stratified into 3 groups: Group I included girls living in a suburban area; Group II girls lived in an urban area, and Group III girls lived in an urban area and wore concealing clothes for religious reasons. At the end of winter (in April) serum 25-hydroxyvitamin D [25(OH)D] levels were measured and dietary data were collected using questionnaires. Vitamin D deficiency was defined as a serum 25(OH)D concentration dress code; therefore, vitamin D supplementation appears to be necessary for adolescent girls.

  5. Elevated temperature increases carbon and nitrogen fluxes between phytoplankton and heterotrophic bacteria through physical attachment

    KAUST Repository

    Arandia-Gorostidi, Nestor

    2016-12-06

    Quantifying the contribution of marine microorganisms to carbon and nitrogen cycles and their response to predicted ocean warming is one of the main challenges of microbial oceanography. Here we present a single-cell NanoSIMS isotope analysis to quantify C and N uptake by free-living and attached phytoplankton and heterotrophic bacteria, and their response to short-term experimental warming of 4 °C. Elevated temperature increased total C fixation by over 50%, a small but significant fraction of which was transferred to heterotrophs within 12 h. Cell-to-cell attachment doubled the secondary C uptake by heterotrophic bacteria and increased secondary N incorporation by autotrophs by 68%. Warming also increased the abundance of phytoplankton with attached heterotrophs by 80%, and promoted C transfer from phytoplankton to bacteria by 17% and N transfer from bacteria to phytoplankton by 50%. Our results indicate that phytoplankton-bacteria attachment provides an ecological advantage for nutrient incorporation, suggesting a mutualistic relationship that appears to be enhanced by temperature increases.

  6. Soil carbon sequestration in prairie grasslands increased by chronic nitrogen addition.

    Science.gov (United States)

    Fornara, Dario A; Tilman, David

    2012-09-01

    Human-induced increases in nitrogen (N) deposition are common across many terrestrial ecosystems worldwide. Greater N availability not only reduces biological diversity, but also affects the biogeochemical coupling of carbon (C) and N cycles in soil ecosystems. Soils are the largest active terrestrial C pool and N deposition effects on soil C sequestration or release could have global importance. Here, we show that 27 years of chronic N additions to prairie grasslands increased C sequestration in mineral soils and that a potential mechanism responsible for this C accrual was an N-induced increase in root mass. Greater soil C sequestration followed a dramatic shift in plant community composition from native-species-rich C4 grasslands to naturalized-species-rich C3 grasslands, which, despite lower soil C gains per unit of N added, still acted as soil C sinks. Since both high plant diversity and elevated N deposition may increase soil C sequestration, but N deposition also decreases plant diversity, more research is needed to address the long-term implications for soil C storage of these two factors. Finally, because exotic C3 grasses often come to dominate N-enriched grasslands, it is important to determine if such N-dependent soil C sequestration occurs across C3 grasslands in other regions worldwide.

  7. Ozone and increased nitrogen supply effects on the yield and nutritive quality of Trifolium subterraneum

    Science.gov (United States)

    Sanz, J.; Muntifering, R. B.; Bermejo, V.; Gimeno, B. S.; Elvira, S.

    The influence of ambient ozone (O 3) concentrations and nitrogen (N) fertilization, singly and in combination, on the growth and nutritive quality of Trifolium subterraneum was assessed. This is an important O 3-sensitive species of great pastoral value in Mediterranean areas. Plant material was enclosed in open-top chambers (OTCs). Three O 3 levels were established: Filtered air with O 3 concentrations below 15 ppb (CFA), non-filtered air with O 3 concentrations in the range of ambient levels (NFA), and non-filtered air supplemented with 40 ppb O 3 over ambient levels (NFA+). Similarly, three N levels were defined: 5, 15 and 30 kg ha -1. The increase in O 3 exposure induced a reduction of the clover aerial green biomass and an increase of senescent biomass. Ozone effects were more adverse in the root system, inducing an impairment of the aerial/subterranean biomass ratio. Compared with the CFA treatment, nutritive quality of aerial biomass was 10 and 20% lower for NFA and NFA+ treatments, respectively, due to increased concentrations of acid detergent fiber, neutral detergent fiber and lignin. The latter effect appears to be related to senescence acceleration. The increment in N supplementation enhanced the increase of ADF concentrations in those plants simultaneously exposed to ambient and above-ambient O 3 concentrations, and reduced the incremental rate of foliar senescence induced by the pollutant.

  8. Increasing sennoside yields in tinnevelly senna (Cassia angustifolia) I: effects of drought, foliar nitrogen spray and crop type.

    Science.gov (United States)

    Ratnayaka, H; Meurer-Grimes, B; Kincaid, D

    1998-06-01

    Experiments were conducted to evaluate the promise of Tinnevelly senna, Cassia angustifolia Vahl, as an alternative crop for stressful agroecosystems. Effects of drought, foliar nitrogen application and crop type on sennoside yields were studied with simultaneous measurements of net photosynthesis. Short term drought increased sennoside A + B concentration (% dw). After drought-induced morphological changes had occurred, long term drought did not influence sennoside A + B concentration but severe loss of leaf biomass caused 78% reduction of the sennoside yield per plant. Foliar nitrogen application increased the total sennoside A + B content per plant by 140% when the plants were not water stressed, but in severely droughted plants, no effect of foliar nitrogen application was detected. Although foliar nitrogen application increased sennoside A + B per plant, the sennoside concentration (% dw) decreased. The latter effect was still persistent three months after the nitrogen treatments were discontinued. In a comparison among three crop types of Tinnevelly senna, ratoon plants had the highest sennoside A + B concentration in leaves followed by seedlings and cuttings. However, seedlings produced the highest sennoside A + B yield per plant due to the higher leaf biomass. Except in long term drought, sennoside levels were higher in leaves with lower net photosynthesis, and were increased by treatments that induced physiological stress. Lower net photosynthesis occurred in short term and long term drought, and with deprivation of foliar nitrogen supplement. In contrast, sennoside yields per plant are readily increased by treatments that increase the total leaf biomass. Short term drought, nitrogen stress and ratooning are promising component technologies for field and on-farm investigations with the goal of increasing sennoside yields.

  9. Longer thaw seasons increase nitrogen availability for leaching during fall in tundra soils

    Science.gov (United States)

    Treat, Claire C.; Wollheim, Wilfred M.; Varner, Ruth K.; Bowden, William B.

    2016-06-01

    Climate change has resulted in warmer soil temperatures, earlier spring thaw and later fall freeze-up, resulting in warmer soil temperatures and thawing of permafrost in tundra regions. While these changes in temperature metrics tend to lengthen the growing season for plants, light levels, especially in the fall, will continue to limit plant growth and nutrient uptake. We conducted a laboratory experiment using intact soil cores with and without vegetation from a tundra peatland to measure the effects of late freeze and early spring thaw on carbon dioxide (CO2) exchange, methane (CH4) emissions, dissolved organic carbon (DOC) and nitrogen (N) leaching from soils. We compared soil C exchange and N production with a 30 day longer seasonal thaw during a simulated annual cycle from spring thaw through freeze-up and thaw. Across all cores, fall N leaching accounted for ˜33% of total annual N loss despite significant increases in microbial biomass during this period. Nitrate ({{{{NO}}}3}-) leaching was highest during the fall (5.33 ± 1.45 mg N m-2 d-1) following plant senescence and lowest during the summer (0.43 ± 0.22 mg N m-2 d-1). In the late freeze and early thaw treatment, we found 25% higher total annual ecosystem respiration but no significant change in CH4 emissions or DOC loss due to high variability among samples. The late freeze period magnified N leaching and likely was derived from root turnover and microbial mineralization of soil organic matter coupled with little demand from plants or microbes. Large N leaching during the fall will affect N cycling in low-lying areas and streams and may alter terrestrial and aquatic ecosystem nitrogen budgets in the arctic.

  10. Effect of nitrogen and phosphorus deficiency on transcriptional regulation of genes encoding key enzymes of starch metabolism in duckweed (Landoltia punctata).

    Science.gov (United States)

    Zhao, Zhao; Shi, Hui-juan; Wang, Mao-lin; Cui, Long; Zhao, Hai; Zhao, Yun

    2015-01-01

    The production of starch by plants influences their use as biofuels. Nitrogen (N) and phosphorus (P) regulate starch gene expression during plant growth and development, yet the role of key enzymes such as ADP-glucose pyrophosphorylase (E.C. 2.7.7.27 AGPase) in starch metabolism during N- and P-deficiency remains unknown. We investigated the effect of N- and P-deficiency on the expression of large (LeAPL1, LeAPL2, and LeAPL3) and small (LeAPS) subunits of AGPase in duckweed (Landoltia punctata) and their correlation with starch content. We first isolated the full-length cDNA encoding LeAPL1 (GenBank Accession No. KJ603244) and LeAPS (GenBank Accession No. KJ603243); they contained open reading frames of 1554 bp (57.7-kDa polypeptide of 517 amino acids) and 1578 bp (57.0 kDa polypeptide of 525 amino acids), respectively. Real-time PCR analysis revealed that LeAPL1 and LeAPL3 were highly expressed during early stages of N-deficiency, while LeAPL2 was only expressed during late stage. However, in response to P-deficiency, LeAPL1 and LeAPL2 were upregulated during early stages and LeAPL3 was primarily expressed in the late stage. Interestingly, LeAPS was highly expressed following N-deficiency during both stages, but was only upregulated in the early stage after P-deficiency. The activities of AGPase and soluble starch synthesis enzyme (SSS EC 2.4.1.21) were positively correlated with changes in starch content. Furthermore, LeAPL3 and LeSSS (SSS gene) were positively correlated with changes in starch content during N-deficiency, while LeAPS and LeSSS were correlated with starch content in response to P-deficiency. These results elevate current knowledge of the molecular mechanisms underlying starch synthesis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. Methionine sulfoxide reductase B1 deficiency does not increase high-fat diet-induced insulin resistance in mice.

    Science.gov (United States)

    Heo, Jung-Yoon; Cha, Hye-Na; Kim, Ki Young; Lee, Eujin; Kim, Suk-Jeong; Kim, Yong-Woon; Kim, Jong-Yeon; Lee, In-Kyu; Gladyshev, Vadim N; Kim, Hwa-Young; Park, So-Young

    2017-01-01

    Methionine-S-sulfoxide reductase (MsrA) protects against high-fat diet-induced insulin resistance due to its antioxidant effects. To determine whether its counterpart, methionine-R-sulfoxide reductase (MsrB) has similar effects, we compared MsrB1 knockout and wild-type mice using a hyperinsulinemic-euglycemic clamp technique. High-fat feeding for eight weeks increased body weights, fat masses, and plasma levels of glucose, insulin, and triglycerides to similar extents in wild-type and MsrB1 knockout mice. Intraperitoneal glucose tolerance test showed no difference in blood glucose levels between the two genotypes after eight weeks on the high-fat diet. The hyperglycemic-euglycemic clamp study showed that glucose infusion rates and whole body glucose uptakes were decreased to similar extents by the high-fat diet in both wild-type and MsrB1 knockout mice. Hepatic glucose production and glucose uptake of skeletal muscle were unaffected by MsrB1 deficiency. The high-fat diet-induced oxidative stress in skeletal muscle and liver was not aggravated in MsrB1-deficient mice. Interestingly, whereas MsrB1 deficiency reduced JNK protein levels to a great extent in skeletal muscle and liver, it markedly elevated phosphorylation of JNK, suggesting the involvement of MsrB1 in JNK protein activation. However, this JNK phosphorylation based on a p-JNK/JNK level did not positively correlate with insulin resistance in MsrB1-deficient mice. Taken together, our results show that, in contrast to MsrA deficiency, MsrB1 deficiency does not increase high-fat diet-induced insulin resistance in mice.

  12. Emerging and Established Technologies to Increase Nitrogen Use Efficiency of Cereals

    Directory of Open Access Journals (Sweden)

    Juan M. Herrera

    2016-04-01

    Full Text Available Nitrogen (N fertilizers are one of the most expensive inputs in agricultural settings. Additionally, the loss of N increases costs, contributes to soil acidification, and causes off-site pollution of the air, groundwater and waterways. This study reviews current knowledge about technologies for N fertilization with potential to increase N use efficiency and reduce its negative effects on the environment. Classic inorganic sources such as urea and ammonium sulfate are the major sources utilized, while controlled N release fertilizers have not been significantly adopted for cereals and oil crops. Microorganisms, with the exception of Rhizobium sp. in soybeans, are also not widely used nowadays (e.g., plant growth-promoting bacteria and cynobacteria. The interest in implementing new N fertilization knowledge is stimulating the development of sensors to diagnose the N status and decision support systems for integrating several variables to optimize sources, rates and methods of application. Among potential new technologies we identified the incipient development of nanofertilizers, nutrient formulations to coat seeds, and recycled nutrients. Furthermore, increasing concern about the environmental consequences of N may facilitate the implementation of innovations outside the farm such as more effective regulations to guide N fertilization and methods to manufacture N fertilizers that are more energy-efficient and less CO2 equivalent emitting.

  13. Increasing temperature reduces the coupling between available nitrogen and phosphorus in soils of Chinese grasslands

    Science.gov (United States)

    Geng, Yan; Baumann, Frank; Song, Chao; Zhang, Mi; Shi, Yue; Kühn, Peter; Scholten, Thomas; He, Jin-Sheng

    2017-03-01

    Changes in climatic conditions along geographical gradients greatly affect soil nutrient cycling processes. Yet how climate regimes such as changes in temperature influence soil nitrogen (N) and phosphorus (P) concentrations and their stoichiometry is not well understood. This study investigated the spatial pattern and variability of soil N and P availability as well as their coupling relationships at two soil layers (0–10 and 10–20 cm) along a 4000-km climate transect in two grassland biomes of China, the Inner Mongolian temperate grasslands and the Tibetan alpine grasslands. Our results found that in both grasslands, from cold to warm sites the amounts of soil total N, total P and available P all decreased. By contrast, the amount of available N was positively related to mean annual temperature in the Tibetan grasslands. Meanwhile, with increasing temperature ratio of available N to P significantly increased but the linear relationship between them was considerably reduced. Thus, increasing temperature may not only induce a stoichiometric shift but also loose the coupling between available N and P. This N-P decoupling under warmer conditions was more evident in the Tibetan alpine grasslands where P limitation might become more widespread relative to N as temperatures continue to rise.

  14. Elevated relative humidity increases the incidence of boron deficiency in bedding plants

    Science.gov (United States)

    High relative humidity (RH) can cause lower concentrations of B accumulating in plants. The common greenhouse practice of controlling excess temperatures by applying mist irrigation to youngplants (plugs) results in elevated RH levels. Reports of boron (B) deficiency have become more prevalent ove...

  15. Lack of increased prevalence of immunoregulatory disorders in hereditary angioedema due to C1-inhibitor deficiency.

    Science.gov (United States)

    Farkas, Henriette; Csuka, Dorottya; Gács, Judit; Czaller, Ibolya; Zotter, Zsuzsanna; Füst, George; Varga, Lilian; Gergely, Péter

    2011-10-01

    Hereditary angioedema due to deficiency of C1-INH (HAE-C1-INH) is associated with enhanced consumption of the early complement components, which may predispose for autoimmune disease. We assessed the prevalence of such disorders among HAE- C1-INH patients and their impact on the natural course of HAE-C1-INH. Clinical data and immunoserological parameters of 130 HAE-C1-INH and 174 non-C1-INH-deficient patients with angioedema were analyzed. In our study, the incidence of immunoregulatory disorders was 11.5% in the population of HAE-C1-INH patients and 5.2% among non-C1-INH-deficient controls with angioedema. Immunoserology screening revealed a greater prevalence of anticardiolipin IgM (p=0.0118) among HAE-C1-INH patients, than in those with non-C1-INH-deficient angioedema. We did not find higher prevalence of immunoregulatory disorders among our HAE-C1-INH patients. However, in patients with confirmed immunoregulatory disorders, the latter influenced both the severity of HAE-C1-INH and the effectiveness of its long-term management. Appropriate management of the immunoregulatory disease thus identified improves the symptoms of HAE-C1-INH.

  16. Increased heart rate variability but normal resting metabolic rate in hypocretin/orexin-deficient human narcolepsy.

    NARCIS (Netherlands)

    Fronczek, R.; Overeem, S.; Reijntjes, R.; Lammers, G.J.; Dijk, J.G.M.; Pijl, H.

    2008-01-01

    STUDY OBJECTIVES: We investigated autonomic balance and resting metabolic rate to explore their possible involvement in obesity in hypocretin/orexin-deficient narcoleptic subjects. METHODS: Resting metabolic rate (using indirect calorimetry) and variability in heart rate and blood pressure were dete

  17. Nitrogen availability increases in a tundra ecosystem during five years of experimental permafrost thaw.

    Science.gov (United States)

    Salmon, Verity G; Soucy, Patrick; Mauritz, Marguerite; Celis, Gerardo; Natali, Susan M; Mack, Michelle C; Schuur, Edward A G

    2016-05-01

    Perennially frozen soil in high latitude ecosystems (permafrost) currently stores 1330-1580 Pg of carbon (C). As these ecosystems warm, the thaw and decomposition of permafrost is expected to release large amounts of C to the atmosphere. Fortunately, losses from the permafrost C pool will be partially offset by increased plant productivity. The degree to which plants are able to sequester C, however, will be determined by changing nitrogen (N) availability in these thawing soil profiles. N availability currently limits plant productivity in tundra ecosystems but plant access to N is expected improve as decomposition increases in speed and extends to deeper soil horizons. To evaluate the relationship between permafrost thaw and N availability, we monitored N cycling during 5 years of experimentally induced permafrost thaw at the Carbon in Permafrost Experimental Heating Research (CiPEHR) project. Inorganic N availability increased significantly in response to deeper thaw and greater soil moisture induced by Soil warming. This treatment also prompted a 23% increase in aboveground biomass and a 49% increase in foliar N pools. The sedge Eriophorum vaginatum responded most strongly to warming: this species explained 91% of the change in aboveground biomass during the 5 year period. Air warming had little impact when applied alone, but when applied in combination with Soil warming, growing season soil inorganic N availability was significantly reduced. These results demonstrate that there is a strong positive relationship between the depth of permafrost thaw and N availability in tundra ecosystems but that this relationship can be diminished by interactions between increased thaw, warmer air temperatures, and higher levels of soil moisture. Within 5 years of permafrost thaw, plants actively incorporate newly available N into biomass but C storage in live vascular plant biomass is unlikely to be greater than losses from deep soil C pools.

  18. Increased bioplastic production with an RNA polymerase sigma factor SigE during nitrogen starvation in Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Osanai, Takashi; Numata, Keiji; Oikawa, Akira; Kuwahara, Ayuko; Iijima, Hiroko; Doi, Yoshiharu; Tanaka, Kan; Saito, Kazuki; Hirai, Masami Yokota

    2013-12-01

    Because cyanobacteria directly harvest CO2 and light energy, their carbon metabolism is important for both basic and applied sciences. Here, we show that overexpression of the sigma factor sigE in Synechocystis sp. PCC 6803 widely changes sugar catabolism and increases production of the biodegradable polyester polyhydroxybutyrate (PHB) during nitrogen starvation. sigE overexpression elevates the levels of proteins implicated in glycogen catabolism, the oxidative pentose phosphate pathway, and polyhydroxyalkanoate biosynthesis. PHB accumulation is enhanced by sigE overexpression under nitrogen-limited conditions, yet the molecular weights of PHBs synthesized by the parental glucose-tolerant and sigE overexpression strain are similar. Although gene expression induced by nitrogen starvation is changed and other metabolites (such as GDP-mannose and citrate) accumulate under sigE overexpression, genetic engineering of this sigma factor altered the metabolic pathway from glycogen to PHB during nitrogen starvation.

  19. Increased nitrogen use efficiency of a short-rotation poplar plantation is increased under elevated CO2

    NARCIS (Netherlands)

    Calfapietra, C.; Angelis, de P.; Gielen, B.; Lukac, M.; Moscatelli, M.C.; Avino, G.; Lagomarsino, A.; Polle, A.; Ceulemans, R.; Mugnozza, G.S.; Hoosbeek, M.R.; Cotrufo, M.F.

    2007-01-01

    We estimated nitrogen (N) use by trees of three poplar species exposed for 3 years to free air CO2 enrichment (FACE) and determined whether the CO2 treatment affected the future N availability of the plantation. Trees were harvested at the end of the first 3-year rotation and N concentration and con

  20. Increased influence of nitrogen limitation on CO2 emissions from future land use and land use change

    Science.gov (United States)

    Meiyappan, Prasanth; Jain, Atul K.; House, Joanna I.

    2015-09-01

    In the latest projections of future greenhouse gas emissions for the Intergovernmental Panel on Climate Change (IPCC), few Earth System Models included the effect of nitrogen limitation, a key process limiting forest regrowth. Few included forest management (wood harvest). We estimate the impacts of nitrogen limitation on the CO2 emissions from land use and land use change (LULUC), including wood harvest, for the period 1900-2100. We use a land surface model that includes a fully coupled carbon and nitrogen cycle and accounts for forest regrowth processes following agricultural abandonment and wood harvest. Future projections are based on the four Representation Concentration Pathways used in the IPCC Fifth Assessment Report, and we account for uncertainty in future climate for each scenario based on ensembles of climate model outputs. Results show that excluding nitrogen limitation will underestimate global LULUC emissions by 34-52 PgC (20-30%) during the 20th century (range across three different historical LULUC reconstructions) and by 128-187 PgC (90-150%) during the 21st century (range across the four IPCC scenarios). The full range for estimated LULUC emissions during the 21st century including climate model uncertainty is 91 to 227 PgC (with nitrogen limitation included). The underestimation increases with time because (1) projected annual wood harvest rates from forests summed over the 21st century are 380-1080% higher compared to those of the 20th century, resulting in more regrowing secondary forests; (2) nitrogen limitation reduces the CO2 fertilization effect on net primary production of regrowing secondary forests following wood harvest and agricultural abandonment; and (3) nitrogen limitation effect is aggravated by the gradual loss of soil nitrogen from LULUC disturbance. Our study implies that (1) nitrogen limitation of CO2 uptake is substantial and sensitive to nitrogen inputs; (2) if LULUC emissions are larger than previously estimated in studies

  1. Enhanced nitrogen removal in single-chamber microbial fuel cells with increased gas diffusion areas

    KAUST Repository

    Yan, Hengjing

    2012-11-23

    Single-chamber microbial fuel cells (MFCs) with nitrifiers pre-enriched at the air cathodes have previously been demonstrated as a passive strategy for integrating nitrogen removal into current-generating bioelectrochemical systems. To further define system design parameters for this strategy, we investigated in this study the effects of oxygen diffusion area and COD/N ratio in continuous-flow reactors. Doubling the gas diffusion area by adding an additional air cathode or a diffusion cloth significantly increased the ammonia and COD removal rates (by up to 115% and 39%), ammonia removal efficiency (by up to 134%), the cell voltage and cathode potentials, and the power densities (by a factor of approximately 2). When the COD/N ratio was lowered from 13 to 3, we found up to 244% higher ammonia removal rate but at least 19% lower ammonia removal efficiency. An increase of COD removal rate by up to 27% was also found when the COD/N ratio was lowered from 11 to 3. The Coulombic efficiency was not affected by the additional air cathode, but decreased by an average of 11% with the addition of a diffusion cloth. Ammonia removal by assimilation was also estimated to understand the ammonia removal mechanism in these systems. These results showed that the doubling of gas diffusion area enhanced N and COD removal rates without compromising electrochemical performance. © 2012 Wiley Periodicals, Inc.

  2. Adipocyte (Pro)Renin-Receptor Deficiency Induces Lipodystrophy, Liver Steatosis and Increases Blood Pressure in Male Mice.

    Science.gov (United States)

    Wu, Chia-Hua; Mohammadmoradi, Shayan; Thompson, Joel; Su, Wen; Gong, Ming; Nguyen, Genevieve; Yiannikouris, Frédérique

    2016-07-01

    Adipose tissue dysfunction related to obesity is overwhelmingly associated with increased risk of developing cardiovascular diseases. In the setting of obesity, (pro)renin receptor (PRR) is increased in adipose tissue of mice. We sought to determine the physiological consequences of adipocyte-PRR deficiency using adiponectin-Cre mice. We report a unique model of adipocyte-PRR-deficient mice (PRR(Adi/Y)) with almost no detectable white adipose tissues. As a consequence, the livers of PRR(Adi/Y) mice were enlarged and demonstrated a marked accumulation of lipids. Adipocyte-specific deficiency of PRR increased systolic blood pressure and the concentration of soluble PRR in plasma. To determine whether adipocyte-PRR was involved in the development of obesity-induced hypertension, mice were fed a low-fat or a high-fat diet for 16 weeks. Adipocyte-PRR-deficient mice were resistant to diet-induced obesity. Both high-fat- and low-fat-fed PRR(Adi/Y) mice had elevated insulin levels. Interestingly, adipocyte-PRR deficiency improved glucose tolerance in high-fat-fed PRR(Adi/Y) mice. In response to feeding either low-fat or high-fat diets, systolic blood pressure was greater in PRR(Adi/Y) mice than in control mice. High-fat feeding elevated soluble PRR concentration in control and PRR(Adi/Y) mice. In vitro knockdown of PRR by siRNA significantly decreased mRNA abundance of PPARγ (peroxisome proliferator-activated receptor gamma), suggesting an important role for PRR in adipogenesis. Our data indicate that adipocyte-PRR is involved in lipid homeostasis and glucose and insulin homeostasis, and that soluble PRR may be a predictor of metabolic disturbances and play a role in systolic blood pressure regulation.

  3. Nonlinear response of soil respiration to increasing nitrogen additions in a Tibetan alpine steppe

    Science.gov (United States)

    Peng, Yunfeng; Li, Fei; Zhou, Guoying; Fang, Kai; Zhang, Dianye; Li, Changbin; Yang, Guibiao; Wang, Guanqin; Wang, Jun; Mohammat, Anwar; Yang, Yuanhe

    2017-02-01

    Nitrogen (N) availability is a key regulator of carbon (C) cycling in terrestrial ecosystems. Anthropogenic N input, such as N deposition and fertilization, increases N availability in soil, which has important implications for an ecosystem’s C storage and loss. Soil respiration (Rs), which is the second largest C flux from terrestrial ecosystems to the atmosphere, plays an important role in terrestrial C cycles. The direction and magnitude of the responses of Rs and its components to N addition have been widely evaluated, but it remains unclear how these processes change across multiple N addition levels. Here we conducted a two-year field experiment to examine the changes of Rs and its autotrophic respiration (Ra) and heterotrophic respiration (Rh) components along a gradient of eight N levels (0, 1 2, 4, 8, 16, 24, 32 g m‑2 yr‑1) in a Tibetan alpine steppe, and used structural equation modeling (SEM) to explore the relative contributions of biotic and abiotic variables and their direct and indirect pathways regulating the Ra and Rh. Our results indicated that both Rs and Ra exhibited first increasing and then subsequent decreasing trends at the threshold of 8 g N m‑2 yr‑1. In contrast, the Rh declined linearly with the N addition rate continuously increasing. SEM analysis revealed that, among various environmental factors, soil temperature was the most important one modulating Rs, which not only had a direct effect on the two Rs components, but also indirectly regulated the Ra and Rh via root and microbial biomass. These findings suggest that the nonlinear response patterns of Rs should be considered for better predicting terrestrial C balance, given that anthropogenic N input to the terrestrial ecosystems is increasing continuously.

  4. Selection of nitrogen-fixing deficient Burkholderia vietnamiensis strains by cystic fibrosis patients: involvement of nif gene deletions and auxotrophic mutations.

    Science.gov (United States)

    Menard, Aymeric; Monnez, Claire; Estrada de Los Santos, Paulina; Segonds, Christine; Caballero-Mellado, Jesus; Lipuma, John J; Chabanon, Gerard; Cournoyer, Benoit

    2007-05-01

    Burkholderia vietnamiensis is the third most prevalent species of the Burkholderia cepacia complex (Bcc) found in cystic fibrosis (CF) patients. Its ability at fixing nitrogen makes it one of the main Bcc species showing strong filiations with environmental reservoirs. In this study, 83% (29 over 35) of the B. vietnamiensis CF isolates and 100% of the environmental ones (over 29) were found expressing the dinitrogenase complex (encoded by the nif cluster) which is essential in N(2) fixation. Among the deficient strains, two were found growing with ammonium chloride suggesting that they were defective in N(2) fixation, and four with amino acids supplements suggesting that they were harbouring auxotrophic mutations. To get insights about the genetic events that led to the emergence of the N(2)-fixing defective strains, a genetic analysis of B. vietnamiensis nitrogen-fixing property was undertaken. A 40-kb-long nif cluster and nif regulatory genes were identified within the B. vietnamiensis strain G4 genome sequence, and analysed. Transposon mutagenesis and nifH genetic marker exchanges showed the nif cluster and several other genes like gltB (encoding a subunit of the glutamate synthase) to play a key role in B. vietnamiensis ability at growing in nitrogen-free media. nif cluster DNA probings of restricted genomic DNA blots showed a full deletion of the nif cluster for one of the N(2)-fixing defective strain while the other one showed a genetic organization similar to the one of the G4 strain. For 17% of B. vietnamiensis clinical strains, CF lungs appeared to have favoured the selection of mutations or deletions leading to N(2)-fixing deficiencies.

  5. Methamphetamine Increases Locomotion and Dopamine Transporter Activity in Dopamine D5 Receptor-Deficient Mice

    OpenAIRE

    Seiji Hayashizaki; Shinobu Hirai; Yumi Ito; Yoshiko Honda; Yosefu Arime; Ichiro Sora; Haruo Okado; Tohru Kodama; Masahiko Takada

    2013-01-01

    Dopamine regulates the psychomotor stimulant activities of amphetamine-like substances in the brain. The effects of dopamine are mediated through five known dopamine receptor subtypes in mammals. The functional relevance of D5 dopamine receptors in the central nervous system is not well understood. To determine the functional relevance of D5 dopamine receptors, we created D5 dopamine receptor-deficient mice and then used these mice to assess the roles of D5 dopamine receptors in the behaviora...

  6. Increased influence of nitrogen limitation on CO2 emissions from future land use and land-use change

    Science.gov (United States)

    Jain, A. K.; Meiyappan, P.; House, J.

    2015-12-01

    In the latest projections of future greenhouse gas emissions for the Intergovernmental Panel on Climate Change (IPCC), few Earth System Models included the effect of nitrogen limitation, a key process limiting forest regrowth. We estimate the impacts of nitrogen limitation on the CO2 emissions from land use and land-use change (LULUC), including wood harvest, for the period 1900-2100. We use a land-surface model that includes a fully coupled carbon and nitrogen cycle, and accounts for forest regrowth processes following agricultural abandonment and wood harvest. Future projections are based on the four Representation Concentration Pathways used in the IPCC Fifth Assessment Report, and we account for uncertainty in future climate for each scenario based on ensembles of climate model outputs. Results show that excluding nitrogen limitation will underestimate global LULUC emissions by 34-52 PgC (20-30%) during the 20th century (range across three different historical LULUC reconstructions) and by 128-187 PgC (90-150%) during the 21st century (range across the four IPCC scenarios). The full range for estimated LULUC emissions during the 21st century including climate model uncertainty is 91 to 227 PgC (with nitrogen limitation included). The underestimation increases with time because: (1) Projected annual wood harvest rates from forests summed over the 21st century are 380-1080% higher compared to those of the 20th century, resulting in more regrowing secondary forests, (2) Nitrogen limitation reduces the CO2 fertilization effect on net primary production of regrowing secondary forests following wood harvest and agricultural abandonment, and (3) Nitrogen limitation effect is aggravated by the gradual loss of soil nitrogen from LULUC disturbance. Our study implies that: (1) Nitrogen limitation of CO2 uptake is substantial and sensitive to nitrogen inputs, (2) If LULUC emissions are larger than previously estimated in studies without nitrogen limitation, then meeting

  7. Nutrient amendment does not increase mineralisation of sequestered carbon during incubation of a nitrogen limited mangrove soil

    KAUST Repository

    Keuskamp, Joost A.

    2013-02-01

    Mangrove forests are sites of intense carbon and nutrient cycling, which result in soil carbon sequestration on a global scale. Currently, mangrove forests receive increasing quantities of exogenous nutrients due to coastal development. The present paper quantifies the effects of nutrient loading on microbial growth rates and the mineralisation of soil organic carbon (SOC) in two mangrove soils contrasting in carbon content. An increase in SOC mineralisation rates would lead to the loss of historically sequestered carbon and an enhanced CO2 release from these mangrove soils.In an incubation experiment we enriched soils from Avicennia and Rhizophora mangrove forests bordering the Red Sea with different combinations of nitrogen, phosphorus and glucose to mimic the effects of wastewater influx. We measured microbial growth rates as well as carbon mineralisation rates in the natural situation and after enrichment. The results show that microbial growth is energy limited in both soils, with nitrogen as a secondary limitation. Nitrogen amendment increased the rate at which labile organic carbon was decomposed, while it decreased SOC mineralisation rates. Such an inhibitory effect on SOC mineralisation was not found for phosphorus enrichment.Our data confirm the negative effect of nitrogen enrichment on the mineralisation of recalcitrant carbon compounds found in other systems. Based on our results it is not to be expected that nutrient enrichment by itself will cause degradation of historically sequestered soil organic carbon in nitrogen limited mangrove forests. © 2012 Elsevier Ltd.

  8. Alteration of soil carbon and nitrogen pools and enzyme activities as affected by increased soil coarseness

    Science.gov (United States)

    Wang, Ruzhen; Lü, Linyou; Creamer, Courtney A.; Dijkstra, Feike A.; Liu, Heyong; Feng, Xue; Yu, Guoqing; Han, Xingguo; Jiang, Yong

    2017-04-01

    Soil coarseness decreases ecosystem productivity, ecosystem carbon (C) and nitrogen (N) stocks, and soil nutrient contents in sandy grasslands subjected to desertification. To gain insight into changes in soil C and N pools, microbial biomass, and enzyme activities in response to soil coarseness, a field experiment was conducted by mixing native soil with river sand in different mass proportions: 0, 10, 30, 50, and 70 % sand addition. Four years after establishing plots and 2 years after transplanting, soil organic C and total N concentrations decreased with increased soil coarseness down to 32.2 and 53.7 % of concentrations in control plots, respectively. Soil microbial biomass C (MBC) and N (MBN) declined with soil coarseness down to 44.1 and 51.9 %, respectively, while microbial biomass phosphorus (MBP) increased by as much as 73.9 %. Soil coarseness significantly decreased the enzyme activities of β-glucosidase, N-acetyl-glucosaminidase, and acid phosphomonoesterase by 20.2-57.5 %, 24.5-53.0 %, and 22.2-88.7 %, used for C, N and P cycling, respectively. However, observed values of soil organic C, dissolved organic C, total dissolved N, available P, MBC, MBN, and MBP were often significantly higher than would be predicted from dilution effects caused by the sand addition. Soil coarseness enhanced microbial C and N limitation relative to P, as indicated by the ratios of β-glucosidase and N-acetyl-glucosaminidase to acid phosphomonoesterase (and MBC : MBP and MBN : MBP ratios). Enhanced microbial recycling of P might alleviate plant P limitation in nutrient-poor grassland ecosystems that are affected by soil coarseness. Soil coarseness is a critical parameter affecting soil C and N storage and increases in soil coarseness can enhance microbial C and N limitation relative to P, potentially posing a threat to plant productivity in sandy grasslands suffering from desertification.

  9. Forest liming increases forest floor carbon and nitrogen stocks in a mixed hardwood forest.

    Science.gov (United States)

    Melvin, April M; Lichstein, Jeremy W; Goodale, Christine L

    2013-12-01

    In acid-impacted forests, decreased soil pH and calcium (Ca) availability have the potential to influence biotic and abiotic controls on carbon (C) and nitrogen (N) cycling. We investigated the effects of liming on above- and belowground C and N pools and fluxes 19 years after lime addition to the Woods Lake Watershed, Adirondack Park, New York, USA. Soil pH and exchangeable Ca remained elevated in the forest floor and upper mineral soil of limed areas. Forest floor C and N stocks were significantly larger in limed plots (68 vs. 31 Mg C/ha, and 3.0 vs. 1.5 Mg N/ha), resulting from a larger mass of Oa material. Liming reduced soil basal respiration rates by 17% and 43% in the Oe and Oa horizons, respectively. Net N mineralization was significantly lower in the limed soils for both forest floor horizons. Additional measurements of forest floor depth outside of our study plots, but within the treatment and control subcatchments also showed a deeper forest floor in limed areas; however, the mean depth of limed forest floor was 5 cm shallower than that observed in our study plots. Using a differential equation model of forest floor C dynamics, we found that liming effects on C fluxes measured within our study plots could explain the small observed increase in the Oe C stock but were not large enough to explain the increase in the Oa. Our catchment-wide assessment of forest floor depth, however, indicates that our plot analysis may be an overestimate of ecosystem-scale C and N stocks. Our results suggest that the mechanisms identified in our study, primarily liming-induced reduction in decomposition rates, may account for much of the observed increase in forest floor C. These findings emphasize the importance of understanding of the effects of liming in hardwood forests, and the long-term impacts of acid deposition on forest C and N uptake and retention.

  10. Reducing Nitrogen Pollution while Decreasing Farmers' Costs and Increasing Fertilizer Industry Profits.

    Science.gov (United States)

    Kanter, David R; Zhang, Xin; Mauzerall, Denise L

    2015-03-01

    Nitrogen (N) pollution is emerging as one of the most important environmental issues of the 21st Century, contributing to air and water pollution, climate change, and stratospheric ozone depletion. With agriculture being the dominant source, we tested whether it is possible to reduce agricultural N pollution in a way that benefits the environment, reduces farmers' costs, and increases fertilizer industry profitability, thereby creating a "sweet spot" for decision-makers that could significantly increase the viability of improved N management initiatives. Although studies of the economic impacts of improved N management have begun to take into account farmers and the environment, this is the first study to consider the fertilizer industry. Our "sweet spot" hypothesis is evaluated via a cost-benefit analysis of moderate and ambitious N use efficiency targets in U.S. and China corn sectors over the period 2015-2035. We use a blend of publicly available crop and energy price projections, original time-series modeling, and expert elicitation. The results present a mixed picture: although the potential for a "sweet spot" exists in both countries, it is more likely that one occurs in China due to the currently extensive overapplication of fertilizer, which creates a greater potential for farmers and the fertilizer industry to gain economically from improved N management. Nevertheless, the environmental benefits of improving N management consistently dwarf the economic impacts on farmers and the fertilizer industry in both countries, suggesting that viable policy options could include incentives to farmers and the fertilizer industry to increase their support for N management policies.

  11. Increased responsiveness to dietary lysine deficiency of pectoralis major muscle protein turnover in broilers selected on breast development.

    Science.gov (United States)

    Tesseraud, S; Temim, S; Le Bihan-Duval, E; Chagneau, A M

    2001-04-01

    It has been previously established that growth and carcass qualities of chicks are modified by genotype and dietary amino acid supply. In this study, we evaluated the effects of lysine deficiency and genetic selection on muscle protein metabolism. Chicks originating from an experimental line selected for breast development (QL) and its control line (CL) were provided ad libitum access to isoenergetic diets containing 20% crude protein but differing in their lysine content (0.75 or 1.01%). Protein fractional synthesis rates (FSR) were measured in vivo in the pectoralis major and sartorius muscles of 3-wk-old chickens (flooding dose of [3H]phenylalanine). Fractional breakdown rates (FBR) were estimated as the difference between synthesis and deposition. Lysine deficiency reduced (P 0.14). In the pectoralis major muscle, chicks of both lines receiving an adequate lysine intake also exhibited similar protein turnover rates. However, in chicks fed the lysine-deficient (0.75% lysine) diet, FSR and Cs were higher in QL than in CL chicks (P < 0.05), and FBR tended (P = 0.07) to be higher in QL chicks. This increased protein turnover in the QL birds on the lysine-deficient diet suggests that the responsiveness of muscle protein metabolism to amino acid supply is modified by genetic selection for breast development.

  12. Managing Nitrogen in Croplands: Implications for Increasing Ecosystem Services in Agricultural Landscapes

    Science.gov (United States)

    Jackson, L.

    2011-12-01

    Many agricultural landscapes in the temperate zone are dominated by agroecosystems that are managed with high inputs of agrochemicals, including synthetic nitrogen (N) fertilizers. The process of agricultural intensification increases crop production per unit area, but also often results in loss of environmental quality (such as N contamination of waters, eutrophication, atmospheric N deposition, and emissions of nitrous oxide (N2O), a potent greenhouse gas). Loss of biodiversity and its 'functional homogenization' is another concern. Not only does little land in these landscapes remain in natural ecosystems, but there are negative off-site impacts of intensive agriculture on non-target organisms. Segregating agroecosystems with high-input agricultural production from natural ecosystems (land sparing) is one view to support both food security and biodiversity conservation. But proponents of land sparing rarely address the loss of other ecosystem services, such as those related to environmental quality, health, and human well-being (e.g., livelihoods and cultural values). An emerging view is that increased reliance on ecological processes in agroecosystems ('ecological intensification') is more feasible when the landscape mosaic includes planned and unplanned biodiversity. This requires research on how to support multiple ecosystem services through the integration of agricultural production and biodiversity conservation in the same landscape, and how ecological and physico-chemical processes at various spatial scales are interlinked. It is an enormous challenge to increase reliance on ecological processes for N availability for crop productivity. There are skeptics who think that this will be detrimental for food security, despite benefits for other types of ecosystem services. Using examples from agricultural landscapes in California, mechanisms for ecologically-based N cycling will be discussed, such as: 1) increasing the reservoir of soil organic N and the

  13. Response of Vallisneria natans to Increasing Nitrogen Loading Depends on Sediment Nutrient Characteristics

    Directory of Open Access Journals (Sweden)

    Jiao Gu

    2016-11-01

    Full Text Available High nitrogen (N loading may contribute to recession of submerged macrophytes in shallow lakes; yet, its influences vary depending on environmental conditions. In August 2013, we conducted a 28-day factorial-designed field mesocosm experiment in Lake Taihu at the Taihu Laboratory for Lake Ecosystem Research (TLLER to examine the effects of high N loading on the growth of Vallisneria natans in systems with contrasting sediment types. We ran the experiments with two levels of nutrient loading—present-day external nutrient loading (average P: 5 μg·L−1·day−1, N: 130 μg·L−1·day−1 and P: 5 μg·L−1·day−1, and with three times higher N loading (N: 390 μg·L−1·day−1 and used sediment with two contrasting nutrient levels. V. natans growth decreased significantly with increasing N loading, the effect being dependent, however, on the nutrient status of the sediment. In low nutrient sediment, relative growth rates, leaf biomass and root biomass decreased by 11.9%, 18.2% and 23.3%, respectively, at high rather than low N loading, while the decline was larger (44.0%, 32.7% and 41.8%, respectively when using high nutrient sediment. The larger effect in the nutrient-rich sediment may reflect an observed higher shading of phytoplankton and excess nutrient accumulation in plant tissue, though potential toxic effects of the high-nutrient sediment may also have contributed. Our study confirms the occurrence of a negative effect of increasing N loading on submerged plant growth in shallow nutrient-enriched lakes and further shows that this effect is augmented when the plants grow in nutrient-rich sediment. External N control may, therefore, help to protect or restore submerged macrophytes, especially when the sediment is enriched with nutrients and organic matter.

  14. Nitrogen Additions Increase the Diversity of Carbon Compounds Degraded by Fungi in Boreal Forests

    Science.gov (United States)

    Gartner, T. B.; Turner, K. M.; Treseder, K. K.

    2004-12-01

    Boreal forest soils in North America harbor a large reservoir of organic C, and this region is increasingly exposed to long-range atmospheric N transport from Eurasia. By examining the responses of decomposers to N deposition in these forests, we hope to improve predictions of the fate of boreal carbon pools under global change. We tested the hypothesis that the functional diversity of decomposer fungi would increase under N fertilization in boreal forests where fungal growth was otherwise N-limited, owing to a reduction in competitive exclusion of fungal groups. We collected soil and leaf litter from three Alaskan sites that represent different successional stages at 5, 17, or 80 years following severe forest fire. Each site had been exposed for two years to nitrogen and phosphorus fertilization in a factorial design, with four plots per treatment. Nutrient limitation of fungal growth varied depending on successional stage. The standing hyphal length of decomposer fungi in soil (i.e. Ascomycota and Basidiomycota) responded to neither N nor P in the 5-year old site, increased under N fertilization in the 17-year old site, and increased where N and P was added simultaneously in the 80-year old site (site x N x P interaction: P = 0.001). We used BIOLOG microplates for filamentous fungi to obtain an index of the diversity of carbon use by decomposer fungi; each of 95 wells of these plates contains a different carbon-based compound, as well as a dye that changes color upon metabolism of the compound. Saline leaf litter extracts were mixed with fungal growth medium and then added to the microplates. The number of wells displaying metabolic activity was counted following incubation for five days. We found that N fertilization raised the average number of positive wells per plate from 14 to 27 (P = 0.012), with no significant differences in responses among sites. Phosphorus additions did not alter functional diversity of fungi in any site. Since increases in functional

  15. Biglycan deficiency increases osteoclast differentiation and activity due to defective osteoblasts

    DEFF Research Database (Denmark)

    Bi, Yanming; Nielsen, Karina L; Kilts, Tina M;

    2006-01-01

    the effects of Bgn on 1alpha, 25-dihydroxyvitamin D(3) (1,25-(OH)(2)D(3))-induced osteoclast differentiation and bone resorption in an co-culture of calvariae-derived pre-osteoblasts and osteoclast precursors derived from spleen or bone marrow. Time course and dose response experiments showed that tartrate...... protease inhibitor (slpi) in bgn deficient osteoblasts treated with 1,25-(OH)(2)D(3). These findings point to a novel molecular factor made by osteoblasts that could potentially be involved in LPS-induced osteolysis....

  16. [Mechanisms for the increased fertilizer nitrogen use efficiency of rice in wheat-rice rotation system under combined application of inorganic and organic fertilizers].

    Science.gov (United States)

    Liu, Yi-Ren; Li, Xiang; Yu, Jie; Shen, Qi-Rong; Xu, Yang-Chun

    2012-01-01

    A pot experiment was conducted to study the effects of combined application of organic and inorganic fertilizers on the nitrogen uptake by rice and the nitrogen supply by soil in a wheat-rice rotation system, and approach the mechanisms for the increased fertilizer nitrogen use efficiency of rice under the combined fertilization from the viewpoint of microbiology. Comparing with applying inorganic fertilizers, combined application of organic and inorganic fertilizers decreased the soil microbial biomass carbon and nitrogen and soil mineral nitrogen contents before tillering stage, but increased them significantly from heading to filling stage. Under the combined fertilization, the dynamics of soil nitrogen supply matched best the dynamics of rice nitrogen uptake and utilization, which promoted the nitrogen accumulation in rice plant and the increase of rice yield and biomass, and increased the fertilizer nitrogen use efficiency of rice significantly. Combined application of inorganic and organic fertilizers also promoted the propagation of soil microbes, and consequently, more mineral nitrogen in soil was immobilized by the microbes at rice early growth stage, and the immobilized nitrogen was gradually released at the mid and late growth stages of rice, being able to better satisfy the nitrogen demand of rice in its various growth and development stages.

  17. Increased and early lipolysis in children with long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency during fast.

    Science.gov (United States)

    Haglind, C Bieneck; Nordenström, A; Ask, S; von Döbeln, U; Gustafsson, J; Stenlid, M Halldin

    2015-03-01

    Children with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHAD) have a defect in the degradation of long-chain fatty acids and are at risk of hypoketotic hypoglycemia and insufficient energy production as well as accumulation of toxic fatty acid intermediates. Knowledge on substrate metabolism in children with LCHAD deficiency during fasting is limited. Treatment guidelines differ between centers, both as far as length of fasting periods and need for night feeds are concerned. To increase the understanding of fasting intolerance and improve treatment recommendations, children with LCHAD deficiency were investigated with stable isotope technique, microdialysis, and indirect calometry, in order to assess lipolysis and glucose production during 6 h of fasting. We found an early and increased lipolysis and accumulation of long chain acylcarnitines after 4 h of fasting, albeit no patients developed hypoglycemia. The rate of glycerol production, reflecting lipolysis, averaged 7.7 ± 1.6 µmol/kg/min, which is higher compared to that of peers. The rate of glucose production was normal for age; 19.6 ± 3.4 µmol/kg/min (3.5 ± 0.6 mg/kg/min). Resting energy expenditure was also normal, even though the respiratory quotient was increased indicating mainly glucose oxidation. The results show that lipolysis and accumulation of long chain acylcarnitines occurs before hypoglycemia in fasting children with LCHAD, which may indicate more limited fasting tolerance than previously suggested.

  18. Decreased elastic energy storage, not increased material stiffness, characterizes central artery dysfunction in fibulin-5 deficiency independent of sex.

    Science.gov (United States)

    Ferruzzi, J; Bersi, M R; Uman, S; Yanagisawa, H; Humphrey, J D

    2015-03-01

    Central artery stiffness has emerged over the past 15 years as a clinically significant indicator of cardiovascular function and initiator of disease. Loss of elastic fiber integrity is one of the primary contributors to increased arterial stiffening in aging, hypertension, and related conditions. Elastic fibers consist of an elastin core and multiple glycoproteins; hence defects in any of these constituents can adversely affect arterial wall mechanics. In this paper, we focus on mechanical consequences of the loss of fibulin-5, an elastin-associated glycoprotein involved in elastogenesis. Specifically, we compared the biaxial mechanical properties of five central arteries-the ascending thoracic aorta, descending thoracic aorta, suprarenal abdominal aorta, infrarenal abdominal aorta, and common carotid artery-from male and female wild-type and fibulin-5 deficient mice. Results revealed that, independent of sex, all five regions in the fibulin-5 deficient mice manifested a marked increase in structural stiffness but also a marked decrease in elastic energy storage and typically an increase in energy dissipation, with all differences being most dramatic in the ascending and abdominal aortas. Given that the primary function of large arteries is to store elastic energy during systole and to use this energy during diastole to work on the blood, fibulin-5 deficiency results in a widespread diminishment of central artery function that can have significant effects on hemodynamics and cardiac function.

  19. Dysfunctional immunometabolic effects of vitamin D deficiency, increased cardiometabolic risk. Potential epidemiological alert in America?

    Science.gov (United States)

    Rosas-Peralta, Martin; Holick, Michael F; Borrayo-Sánchez, Gabriela; Madrid-Miller, Alejandra; Ramírez-Árias, Erick; Arizmendi-Uribe, Efrain

    2017-03-01

    Vitamin D deficiency is a serious public health problem worldwide that affects not only skeletal health, but also a wide range of acute and chronic diseases. However, there is still skepticism because of the lack of randomized, controlled trials to support association studies on the benefits of vitamin D for non-skeletal health. This review was based on articles published during the 1980-2015 obtained from the Cochrane Central Register of controlled trials, MEDLINE and PubMed, and focuses on recent challenges with regard to the definition of vitamin D deficiency and how to achieve optimal serum 25-hydroxyvitamin D levels from dietary sources, supplements, and sun exposure. The effect of vitamin D on epigenetic fetal programming and regulation of genes that may potentially explain why vitamin D could have such lifelong comprehensive health benefits is reviewed. Optimization of vitamin D levels in children and adults around the world has potential benefits to improve skeletal health and to reduce the risk of chronic diseases, including some types of cancer, autoimmune diseases, infectious diseases, type 2 diabetes mellitus, and severe cardiovascular disorders such as atherothrombosis, neurocognitive disorders, and mortality. Copyright © 2017 SEEN. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Mice deficient in dihydrolipoyl succinyl transferase show increased vulnerability to mitochondrial toxins.

    Science.gov (United States)

    Yang, Lichuan; Shi, Qingli; Ho, Daniel J; Starkov, Anatoly A; Wille, Elizabeth J; Xu, Hui; Chen, H L; Zhang, Steven; Stack, Cliona M; Calingasan, Noel Y; Gibson, Gary E; Beal, M Flint

    2009-11-01

    The activity of a key mitochondrial tricarboxylic acid cycle enzyme, alpha-ketoglutarate dehydrogenase complex (KGDHC), declines in many neurodegenerative diseases. KGDHC consists of three subunits. The dihydrolipoyl succinyl transferase (DLST) component is unique to KGDHC. DLST(+/-) mice showed reduced mRNA and protein levels and decreased brain mitochondrial KGDHC activity. Neurotoxic effects of mitochondrial toxins were exacerbated in DLST(+/-) mice. MPTP produced a significantly greater reduction of striatal dopamine and tyrosine hydroxylase-positive neurons in the substantia nigra pars compacta of DLST(+/-) mice. DLST deficiency enhanced the severity of lipid peroxidation in the substantia nigra after MPTP treatment. Striatal lesions induced by either malonate or 3-nitropropionic acid (3-NP) were significantly larger in DLST(+/-) mice than in wildtype controls. DLST deficiency enhanced the 3-NP inhibition of mitochondria enzymes, and 3-NP induced protein and DNA oxidations. These observations support the hypothesis that reductions in KGDHC may impair the adaptability of the brain and contribute to the pathogenesis of neurodegenerative diseases.

  1. Nitrogen Fertilizer Deep Placement for Increased Grain Yield and Nitrogen Recovery Efficiency in Rice Grown in Subtropical China.

    Science.gov (United States)

    Wu, Meng; Li, Guilong; Li, Weitao; Liu, Jia; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2017-01-01

    Field plot experiments were conducted over 3 years (from April 2014 to November 2016) in a double-rice (Oryza sativa L.) cropping system in subtropical China to evaluate the effects of N fertilizer placement on grain yield and N recovery efficiency (NRE). Different N application methods included: no N application (CK); N broadcast application (NBP); N and NPK deep placement (NDP and NPKDP, respectively). Results showed that grain yield and apparent NRE significantly increased for NDP and NPKDP as compared to NBP. The main reason was that N deep placement (NDP) increased the number of productive panicle per m(-2). To further evaluate the increase, a pot experiment was conducted to understand the N supply in different soil layers in NDP during the whole rice growing stage and a (15)N tracing technique was used in a field experiment to investigate the fate of urea-(15)N in the rice-soil system during rice growth and at maturity. The pot experiment indicated that NDP could maintain a higher N supply in deep soil layers than N broadcast for 52 days during rice growth. The (15)N tracing study showed that NDP could maintain much higher fertilizer N in the 5-20 cm soil layer during rice growth and could induce plant to absorb more N from fertilizer and soil than NBP, which led to higher NRE. One important finding was that NDP and NPKDP significantly increased fertilizer NRE but did not lead to N declined in soil compared to NBP. Compared to NPK, NPKDP induced rice plants to absorb more fertilizer N rather than soil N.

  2. Bedrock Nitrogen Contributes to Increased Carbon Storage in Temperate Conifer Forests of Northern California, USA

    Science.gov (United States)

    Morford, S. L.; Houlton, B. Z.; Dahlgren, R. A.

    2010-12-01

    Identifying mechanisms by which nitrogen (N) enters ecosystems is crucial to modeling carbon (C) storage and earth system responses to rising CO2 emissions. Paradigms of nutrient cycling posit that N enters ecosystems solely from the atmosphere; however, rocks contain 99% of all fixed N on Earth, implying a potentially widespread source of ecologically available N. We tested the hypothesis that bedrock N contributes to increased N fertility and C storage of temperate conifer forests underlain by N-rich bedrock in northern California, USA. We used a paired sampling design to measure total N and C, and N stable isotope ratios (15N/14N) of surface mineral soils, bedrock, and foliage from similar forests that differed in parent material: the first site on N-rich (680 ppm N) metasedimentary rock, the second site on N-poor (55 ppm N) igneous rock. In addition, we performed a regional analysis of C storage in aboveground tree biomass using Forest Inventory and Analysis (FIA) plot data (n = 82) from conifer forests on N-rich and N-poor bedrock to examine for C by N interactions at the regional scale. The N content of soils and conifer needles was elevated by more than 50% in the forest underlain by N-rich bedrock, with soil C pools elevated by 60% in N-rich sites. Further, 15N/14N of rock, soils, and plants were indistinguishable in sites underlain by N-rich lithology, whereas foliar 15N/14N from N-poor site was depleted 20‰ relative to rock. Finally, the regional data pointed to substantial effects of N-rich rock on total forest C storage; ecosystem C pools were 40% higher in forests with geologic N than sites with N-poor bedrock minerals. These results suggest that rock weathering can profoundly alter ecosystem N and C cycles, implying an overlooked pathway of N input to terrestrial ecosystems.

  3. Ascorbic acid deficiency leads to increased grain chalkiness in transgenic rice for suppressed of L-GalLDH.

    Science.gov (United States)

    Yu, Le; Liu, Yonghai; Lu, Lina; Zhang, Qilei; Chen, Yezheng; Zhou, Liping; Chen, Hua; Peng, Changlian

    2017-04-01

    The grain chalkiness of rice (Oryza sativa L.), which determines the rice quality and price, is a major concern in rice breeding. Reactive oxygen species (ROS) plays a critical role in regulating rice endosperm chalkiness. Ascorbic acid (Asc) is a major plant antioxidant, which strictly regulates the levels of ROS. l-galactono-1, 4-lactone dehydrogenase (L-GalLDH, EC 1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in higher plants. Here we show that the L-GalLDH-suppressed transgenic rice, GI-1 and GI-2, which have constitutively low (between 30% and 50%) leaf and grain Asc content compared with the wild-type (WT), exhibit significantly increased grain chalkiness. Further examination showed that the deficiency of Asc resulted in a higher lipid peroxidation and H2O2 content, accompanied by a lower hydroxyl radical scavenging rate, total antioxidant capacity and photosynthetic ability. In addition, changes of the enzyme activities and gene transcript abundances related to starch synthesis were also observed in GI-1 and GI-2 grains. The results we presented here suggest a close correlation between Asc deficiency and grain chalkiness in the L-GalLDH-suppressed transgenics. Asc deficiency leads to the accumulation of H2O2, affecting antioxidant capacity and photosynthetic function, changing enzyme activities and gene transcript abundances related to starch synthesis, finally leading to the increased grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.

  4. Leptin Increases Striatal Dopamine D2 Receptor Binding in Leptin-Deficient Obese (ob/ob) Mice

    Energy Technology Data Exchange (ETDEWEB)

    Pfaffly, J.; Michaelides, M.; Wang, G-J.; Pessin, J.E.; Volkow, N.D.; Thanos, P.K.

    2010-06-01

    Peripheral and central leptin administration have been shown to mediate central dopamine (DA) signaling. Leptin-receptor deficient rodents show decreased DA D2 receptor (D2R) binding in striatum and unique DA profiles compared to controls. Leptin-deficient mice show increased DA activity in reward-related brain regions. The objective of this study was to examine whether basal D2R-binding differences contribute to the phenotypic behaviors of leptin-deficient ob/ob mice, and whether D2R binding is altered in response to peripheral leptin treatment in these mice. Leptin decreased body weight, food intake, and plasma insulin concentration in ob/ob mice but not in wild-type mice. Basal striatal D2R binding (measured with autoradiography [{sup 3}H] spiperone) did not differ between ob/ob and wild-type mice but the response to leptin did. In wild-type mice, leptin decreased striatal D2R binding, whereas, in ob/ob mice, leptin increased D2R binding. Our findings provide further evidence that leptin modulates D2R expression in striatum and that these effects are genotype/phenotype dependent.

  5. Deficiency in macrophage-stimulating protein results in spontaneous intestinal inflammation and increased susceptibility toward epithelial damage in zebrafish.

    Science.gov (United States)

    Witte, Merlijn; Huitema, Leonie F A; Nieuwenhuis, Edward E S; Brugman, Sylvia

    2014-12-01

    Several genome-wide association studies have identified the genes encoding for macrophage-stimulating protein (MSP) and its receptor RON (Recepteur d'Origine Nantais) as possible susceptibility factors in inflammatory bowel disease. While it has been shown that the MSP-RON signaling pathway is involved in tissue injury responses, current mouse models for MSP and RON deficiency have not clearly demonstrated a role of MSP-RON signaling in the context of intestinal inflammation. In this study, we report that the recently identified zebrafish Msp mutant (msp(t34230)) develops spontaneous intestinal inflammation over time. From 14 to 28 weeks postfertilization Msp-deficient zebrafish show intestinal eosinophilia, increased intestinal expression of inflammatory marker mmp9, and activation of intestinal goblet cells. Moreover, these Msp mutant zebrafish are more susceptible toward ethanol-induced epithelial damage, which resulted in increased infiltration and proliferation of immune cells within the lamina propria and prolonged intestinal proinflammatory cytokine responses in some mutant fish. In light of the recent development of many tools to visualize, monitor, and genetically modify zebrafish, these Msp-deficient zebrafish will enable in-depth in vivo analysis of epithelial and macrophage-specific MSP-RON signaling in the context of intestinal inflammation.

  6. Does Maternal Vitamin D Deficiency Increase the Risk of Preterm Birth: A Meta-Analysis of Observational Studies

    Directory of Open Access Journals (Sweden)

    Lu-Lu Qin

    2016-05-01

    Full Text Available There are disagreements among researchers about the association between vitamin D deficiency during pregnancy and preterm birth (PTB. Therefore, we conducted a meta-analysis of observational studies to evaluate this association. We performed a systematic literature search of PubMed, MEDLINE and the Cochrane Library through August 2015 with the following keywords: “vitamin D” or “cholecalciferol” or “25-hydroxyvitamin D” or “25(OHD” in combination with “premature birth” or “preterm birth” or “PTB” or “preterm delivery” or “PTD” or “prematurity”. Our meta-analysis of 10 studies included 10,098 participants and found that pregnant women with vitamin D deficiency (maternal serum 25 (OH D levels < 20 ng/mL experienced a significantly increased risk of PTB (odds ratio (OR = 1.29, 95% confidence intervals(CI: 1.16, 1.45 with low heterogeneity (I2 = 25%, p = 0.21. Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In the subgroup analyses, we found that heterogeneity was obvious in prospective cohort studies (I2 = 60%, p = 0.06. In conclusion, pregnant women with vitamin D deficiency during pregnancy have an increasing risk of PTB.

  7. Abundances of the elements in sharp-lined early-type stars from IUE high-dispersion spectrograms; 2, the nitrogen deficiency in mercury- manganese stars

    CERN Document Server

    Roby, S W; Adelman, S J

    1999-01-01

    For pt.I see ibid., vol.419, no.1, p.276-85 (1993). The authors determine nitrogen abundances from co-added IUE high-dispersion SWP spectrograms of four HgMn stars and five normal or superficially normal main-sequence B and A stars. They find N deficiencies in the HgMn stars greater than previously reported (depletion factors of 135-400 relative to the Sun). N abundance discrepancies from UV and IR studies of normal stars are discussed in light of possible non-LTE effects. Their data set for their sample of HgMn stars (observed with a consistent strategy to maximize the benefits of co-additions) is an improvement over the single or few images previously used to derive N abundances for most of these stars. (37 refs).

  8. Effect of increasing levels of nitrogen on yield of tea in different agro-ecological conditions of Pakistan

    Institute of Scientific and Technical Information of China (English)

    F.S. Hamid; Tahira Ahmad

    2006-01-01

    Field experiment was conducted on mature tea bushes of Qi-Men variety at two different altitudes from sealevel i.e. at National Tea Research Institute Shinkiari (1000 m) and on farmer's field in Konsh valley at village Battal (1500m). Different levels of nitrogen with constant dose of phosphorus and potassium were applied to observe the optimal dose of nutrients for highest yield under local edaphic conditions. The experiment was repeated for three consecutive years.The highest yield of fresh tea leaves were obtained by the application of 420 kg ha-1 N followed by the application of 360kg ha-1 N at 1000 masl. The highest dose of nitrogen also reduced significantly the soil pH in the upper (0-15cm) layer depth during 1998 and 1999. During the year 2000, the reduction in soil pH was observed by the application of highest dose of nitrogen but was non-significant at 5% level. The lower soil depth (15-30 cm) showed the reduction in pH with the highest dose of nitrogen during the experimental year but was statistically non significant.At the higher altitude of 1500 masi the highest yield of fresh tea leaves was obtained by the application of 420 kg ha-1during the experimental years but the increase was significant during the year 1999 and 2000. The yield of the fresh tea leaves was positively correlated with the amount of nitrogen application at both the altitudes. The increasing amount of nitrogen decreased the soil pH at both the depths of 0-15cm and 15-30cm. Unlike the lower altitude (1000 m) there was no any significant reduction in the soil pH during 1998 and 1999. A significant reduction in soil pH was found in the year 2000.

  9. Increased Laforin and Laforin Binding to Glycogen Underlie Lafora Body Formation in Malin-deficient Lafora Disease*

    Science.gov (United States)

    Tiberia, Erica; Turnbull, Julie; Wang, Tony; Ruggieri, Alessandra; Zhao, Xiao-Chu; Pencea, Nela; Israelian, Johan; Wang, Yin; Ackerley, Cameron A.; Wang, Peixiang; Liu, Yan; Minassian, Berge A.

    2012-01-01

    The solubility of glycogen, essential to its metabolism, is a property of its shape, a sphere generated through extensive branching during synthesis. Lafora disease (LD) is a severe teenage-onset neurodegenerative epilepsy and results from multiorgan accumulations, termed Lafora bodies (LB), of abnormally structured aggregation-prone and digestion-resistant glycogen. LD is caused by loss-of-function mutations in the EPM2A or EPM2B gene, encoding the interacting laforin phosphatase and malin E3 ubiquitin ligase enzymes, respectively. The substrate and function of malin are unknown; an early counterintuitive observation in cell culture experiments that it targets laforin to proteasomal degradation was not pursued until now. The substrate and function of laforin have recently been elucidated. Laforin dephosphorylates glycogen during synthesis, without which phosphate ions interfere with and distort glycogen construction, leading to LB. We hypothesized that laforin in excess or not removed following its action on glycogen also interferes with glycogen formation. We show in malin-deficient mice that the absence of malin results in massively increased laforin preceding the appearance of LB and that laforin gradually accumulates in glycogen, which corresponds to progressive LB generation. We show that increasing the amounts of laforin in cell culture causes LB formation and that this occurs only with glycogen binding-competent laforin. In summary, malin deficiency causes increased laforin, increased laforin binding to glycogen, and LB formation. Furthermore, increased levels of laforin, when it can bind glycogen, causes LB. We conclude that malin functions to regulate laforin and that malin deficiency at least in part causes LB and LD through increased laforin binding to glycogen. PMID:22669944

  10. Life Cycle Analysis on Fossil Energy Ratio of Algal Biodiesel: Effects of Nitrogen Deficiency and Oil Extraction Technology

    Directory of Open Access Journals (Sweden)

    Hou Jian

    2015-01-01

    Full Text Available Life cycle assessment (LCA has been widely used to analyze various pathways of biofuel preparation from “cradle to grave.” Effects of nitrogen supply for algae cultivation and technology of algal oil extraction on life cycle fossil energy ratio of biodiesel are assessed in this study. Life cycle fossil energy ratio of Chlorella vulgaris based biodiesel is improved by growing algae under nitrogen-limited conditions, while the life cycle fossil energy ratio of biodiesel production from Phaeodactylum tricornutum grown with nitrogen deprivation decreases. Compared to extraction of oil from dried algae, extraction of lipid from wet algae with subcritical cosolvents achieves a 43.83% improvement in fossil energy ratio of algal biodiesel when oilcake drying is not considered. The outcome for sensitivity analysis indicates that the algal oil conversion rate and energy content of algae are found to have the greatest effects on the LCA results of algal biodiesel production, followed by utilization ratio of algal residue, energy demand for algae drying, capacity of water mixing, and productivity of algae.

  11. Life cycle analysis on fossil energy ratio of algal biodiesel: effects of nitrogen deficiency and oil extraction technology.

    Science.gov (United States)

    Jian, Hou; Jing, Yang; Peidong, Zhang

    2015-01-01

    Life cycle assessment (LCA) has been widely used to analyze various pathways of biofuel preparation from "cradle to grave." Effects of nitrogen supply for algae cultivation and technology of algal oil extraction on life cycle fossil energy ratio of biodiesel are assessed in this study. Life cycle fossil energy ratio of Chlorella vulgaris based biodiesel is improved by growing algae under nitrogen-limited conditions, while the life cycle fossil energy ratio of biodiesel production from Phaeodactylum tricornutum grown with nitrogen deprivation decreases. Compared to extraction of oil from dried algae, extraction of lipid from wet algae with subcritical cosolvents achieves a 43.83% improvement in fossil energy ratio of algal biodiesel when oilcake drying is not considered. The outcome for sensitivity analysis indicates that the algal oil conversion rate and energy content of algae are found to have the greatest effects on the LCA results of algal biodiesel production, followed by utilization ratio of algal residue, energy demand for algae drying, capacity of water mixing, and productivity of algae.

  12. Life Cycle Analysis on Fossil Energy Ratio of Algal Biodiesel: Effects of Nitrogen Deficiency and Oil Extraction Technology

    Science.gov (United States)

    Jian, Hou; Jing, Yang; Peidong, Zhang

    2015-01-01

    Life cycle assessment (LCA) has been widely used to analyze various pathways of biofuel preparation from “cradle to grave.” Effects of nitrogen supply for algae cultivation and technology of algal oil extraction on life cycle fossil energy ratio of biodiesel are assessed in this study. Life cycle fossil energy ratio of Chlorella vulgaris based biodiesel is improved by growing algae under nitrogen-limited conditions, while the life cycle fossil energy ratio of biodiesel production from Phaeodactylum tricornutum grown with nitrogen deprivation decreases. Compared to extraction of oil from dried algae, extraction of lipid from wet algae with subcritical cosolvents achieves a 43.83% improvement in fossil energy ratio of algal biodiesel when oilcake drying is not considered. The outcome for sensitivity analysis indicates that the algal oil conversion rate and energy content of algae are found to have the greatest effects on the LCA results of algal biodiesel production, followed by utilization ratio of algal residue, energy demand for algae drying, capacity of water mixing, and productivity of algae. PMID:26000338

  13. Legumes increase rhizosphere carbon and nitrogen relative to cereals in California agricultural plots

    Science.gov (United States)

    Bergman, R.; Maltais-landry, G.

    2013-12-01

    Nitrogen (N) is an essential nutrient to plant growth, therefore a sufficient supply is needed for high yields. By using N-fixing plants like legumes in crop rotation, we can increase soil N and yields of following crops. Furthermore, legumes also affect soil carbon (C) and C:N ratios, which impacts nutrient cycling in soils. We assessed the effects of two legumes (vetch, fava bean) and a cereal mixture (oats and wheat) on soil N and C by comparing both rhizosphere and bulk soils. We studied the impacts of these plants with different management types (organic, low-input conventional, unfertilized) to see if plant effects on soil C and N changed across management. We used plots from the Long-Term Research on Agricultural Systems (LTRAS) experiment (Davis, CA) to conduct this experiment, where three plots were under each management type. Within each of these plots, we sampled three micro-plots, where we collected rhizosphere soil from fava bean, vetch, and cereals as well as bulk soil, i.e. non-rhizosphere soil. We collected 108 samples, each of which were dried and ball-milled into a fine, uniform powder. Tin capsules with 15-30mg of soil were then analyzed with a Carlo Erba Elemental analyzer to measure how much N and C was present in each of the samples. The different management types didn't affect the relationship among plants, but soil C and N were highest in organic and lowest in unfertilized plots. We found that N was significantly higher in legume rhizosphere than cereal rhizosphere and bulk soils. Soil C was also higher in legumes vs. cereals and bulk soils, but the only significant difference was with the bulk soils. This ultimately resulted in lower C:N ratios in the rhizosphere of legumes, only vetch, however, had significantly lower soil C:N than cereals. Vetch had higher N, and lower C and C:N than fava bean, but the difference between the two legumes was never significant. Similarly, cereals had higher C and N and lower C:N than bulk soils, although

  14. Water-removed spectra increase the retrieval accuracy when estimating savanna grass nitrogen and phosphorus concentrations

    NARCIS (Netherlands)

    Ramoelo, A.; Skidmore, A.K.; Schlerf, M.; Mathieu, R.; Heitkonig, I.M.A.

    2011-01-01

    Information about the distribution of grass foliar nitrogen (N) and phosphorus (P) is important for understanding rangeland vitality and for facilitating the effective management of wildlife and livestock. Water absorption effects in the near-infrared (NIR) and shortwave-infrared (SWIR) regions pose

  15. Increasing dissolved nitrogen and phosphorus export by the Pearl River (Zhujiang)

    NARCIS (Netherlands)

    Strokal, Maryna; Kroeze, Carolien; Li, Lili; Luan, Shengji; Wang, Huanzhi; Yang, Shunshun; Zhang, Yisheng

    2015-01-01

    The Pearl River (Zhujiang in Chinese) has been exporting excess of nitrogen (N) and phosphorus (P), causing eutrophication in the coastal waters of southern China for decades. However, sources of these nutrients and their locations are not well studied for the Pearl River basin. As a consequence,

  16. Fertilization with phosphorus increases soil nitrogen absorption in young plants of Eucalyptus grandis.

    Science.gov (United States)

    Corina Graciano; Juan F. Goya; Jorge L. Frangi; Juan J. Guiamet

    2006-01-01

    Nitrogen (N) and phosphorus (P) are the nutrients that most commonly limit tree growth. Interactions between fertilization and soil type are well known, and in soils with moderate or low N availability, N-fertilization is frequently recommended to improve tree nutrition. The aim of this paper was to analyze how different doses of P and N applied in three different...

  17. Dissolved Organic Nitrogen Inputs from Wastewater Treatment Plant Effluents Increase Responses of Planktonic Metabolic Rates to Warming.

    Science.gov (United States)

    Vaquer-Sunyer, Raquel; Conley, Daniel J; Muthusamy, Saraladevi; Lindh, Markus V; Pinhassi, Jarone; Kritzberg, Emma S

    2015-10-06

    Increased anthropogenic pressures on coastal marine ecosystems in the last century are threatening their biodiversity and functioning. Global warming and increases in nutrient loadings are two major stressors affecting these systems. Global warming is expected to increase both atmospheric and water temperatures and increase precipitation and terrestrial runoff, further increasing organic matter and nutrient inputs to coastal areas. Dissolved organic nitrogen (DON) concentrations frequently exceed those of dissolved inorganic nitrogen in aquatic systems. Many components of the DON pool have been shown to supply nitrogen nutrition to phytoplankton and bacteria. Predictions of how global warming and eutrophication will affect metabolic rates and dissolved oxygen dynamics in the future are needed to elucidate their impacts on biodiversity and ecosystem functioning. Here, we experimentally determine the effects of simultaneous DON additions and warming on planktonic community metabolism in the Baltic Sea, the largest coastal area suffering from eutrophication-driven hypoxia. Both bacterioplankton community composition and metabolic rates changed in relation to temperature. DON additions from wastewater treatment plant effluents significantly increased the activation energies for community respiration and gross primary production. Activation energies for community respiration were higher than those for gross primary production. Results support the prediction that warming of the Baltic Sea will enhance planktonic respiration rates faster than it will for planktonic primary production. Higher increases in respiration rates than in production may lead to the depletion of the oxygen pool, further aggravating hypoxia in the Baltic Sea.

  18. The effect of carbohydrate accumulation and nitrogen deficiency on feedback regulation of photosynthesis in beech (Fagus sylvatica) under elevated CO2 concentration

    Science.gov (United States)

    Klem, K.; Urban, O.; Holub, P.; Rajsnerova, P.

    2012-04-01

    One of the main manifestations of global change is an increase in atmospheric CO2 concentration. Elevated concentration of CO2 has stimulating effect on plant photosynthesis and consequently also on the productivity. Long-term studies, however, show that this effect is progressively reduced due to feedback regulation of photosynthesis. The main causes of this phenomenon are considered as two factors: i) increased biomass production consumes a larger amount of nitrogen from the soil and this leads to progressive nitrogen limitation of photosynthesis, particularly at the level of the enzyme Rubisco, ii) the sink capacity is genetically limited and elevated CO2 concentration leads to increased accumulation of carbohydtrates (mainly sucrose, which is the main transport form of assimilates) in leaves. Increased concentrations of carbohydrates leads to a feedback regulation of photosynthesis by both, long-term feedback regulation of synthesis of the enzyme Rubisco, and also due to reduced capacity to produce ATP in the chloroplasts. However, mechanisms for interactive effects of nitrogen and accumulation of non-structural carbohydrates are still not well understood. Using 3-year-old Fagus sylvatica seedlings we have explored the interactive effects of nitrogen nutrition and sink capacity manipulation (sucrose feeding) on the dynamics of accumulation of non-structural carbohydrates and changes in photosynthetic parameters under ambient (385 μmol (CO2) mol-1) and elevated (700 μmol(CO2) mol-1) CO2 concentration. Sink manipulation by sucrose feeding led to a continuous increase of non-structural carbohydrates in leaves, which was higher in nitrogen fertilized seedlings. The accumulation of non-structural carbohydrates was also slightly stimulated by elevated CO2 concentration. Exponential decay (p structural carbohydrates increased. However, this relationship was modified by the nitrogen content. Accumulation of non-structural carbohydrates had relatively smaller effect

  19. Interactive effects of changing climate, increasing atmospheric CO2, nitrogen deposition and disturbance on carbon and nitrogen dynamics in Oregon forests

    Science.gov (United States)

    Hudiburg, T. W.; Law, B. E.; Thornton, P. E.

    2012-12-01

    Disturbance and climate are two of the most important factors governing forest carbon storage and uptake. Disturbances by fire, insects, and diseases that can reduce forest carbon storage have significantly increased in recent years, and this trend is projected to continue. We examined forest carbon dynamics in response to climate, increased atmospheric CO2 and nitrogen deposition in Oregon for the period 2010-2100, assuming current harvest rates would continue. We used the NCAR CLM4 model combined with a regional atmospheric forcing dataset and account for future environmental change using the IPCC RCP 4.5 (moderate GHG reductions) and RCP 8.5 (high emissions) scenarios. For the RCP 4.5 moderate GHG reductions scenario, regional relative humidity remains constant overtime, predicted atmospheric CO2 concentrations rise to 550 ppm and nitrogen deposition varies from 2.2 kg N ha-1 yr-1 in the mesic ecoregions to 3.3 kg N ha-1 yr-1 in the semi-arid ecoregions. This is a change of 5.5 kg N ha-1 yr-1). At the end of the 21st century, predicted regional net ecosystem production (NEP) is 13.7 Tg C yr-1 (107 g C m-2 yr-1) for business-as-usual (BAU) conditions compared with the current NEP of 13.2 ± 1.6 Tg C yr-1 (103 g C m-2 yr-1). There is no significant influence on NEP by changing climate, nitrogen deposition, and increasing CO2 concentrations in the long term for the moderate RCP 4.5 scenario. Increases in BAU net primary production (NPP) are accompanied by increases in heterotrophic respiration (Rh) from a warmer climate, resulting in no change in NEP. Predicted soil mineral nitrogen is maintained for the first 40-50 years and then declines. In Pacific Northwest forests, our results support the hypothesis that increases in NPP and Rh due to climate warming are enhanced by CO2 fertilization and warming until nitrogen limitation occurs and carbon uptake declines following a peak in 2030 and then drops below its current value. We applied clearcut management scenarios

  20. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency.

    Science.gov (United States)

    Lei, Shaohua; Ryu, Junghyun; Wen, Ke; Twitchell, Erica; Bui, Tammy; Ramesh, Ashwin; Weiss, Mariah; Li, Guohua; Samuel, Helen; Clark-Deener, Sherrie; Jiang, Xi; Lee, Kiho; Yuan, Lijuan

    2016-04-27

    Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies.

  1. Increased and prolonged human norovirus infection in RAG2/IL2RG deficient gnotobiotic pigs with severe combined immunodeficiency

    Science.gov (United States)

    Lei, Shaohua; Ryu, Junghyun; Wen, Ke; Twitchell, Erica; Bui, Tammy; Ramesh, Ashwin; Weiss, Mariah; Li, Guohua; Samuel, Helen; Clark-Deener, Sherrie; Jiang, Xi; Lee, Kiho; Yuan, Lijuan

    2016-01-01

    Application of genetically engineered (GE) large animals carrying multi-allelic modifications has been hampered by low efficiency in production and extended gestation period compared to rodents. Here, we rapidly generated RAG2/IL2RG double knockout pigs using direct injection of CRISPR/Cas9 system into developing embryos. RAG2/IL2RG deficient pigs were immunodeficient, characterized by depletion of lymphocytes and either absence of or structurally abnormal immune organs. Pigs were maintained in gnotobiotic facility and evaluated for human norovirus (HuNoV) infection. HuNoV shedding lasted for 16 days in wild type pigs, compared to 27 days (until the end of trials) in RAG2/IL2RG deficient pigs. Additionally, higher HuNoV titers were detected in intestinal tissues and contents and in blood, indicating increased and prolonged HuNoV infection in RAG2/IL2RG deficient pigs and the importance of lymphocytes in HuNoV clearance. These results suggest that GE immunodeficient gnotobiotic pigs serve as a novel model for biomedical research and will facilitate HuNoV studies. PMID:27118081

  2. Surfactant protein d deficiency in mice is associated with hyperphagia, altered fat deposition, insulin resistance, and increased basal endotoxemia.

    Directory of Open Access Journals (Sweden)

    Jacob V Stidsen

    Full Text Available Pulmonary surfactant protein D (SP-D is a host defence lectin of the innate immune system that enhances clearance of pathogens and modulates inflammatory responses. Recently it has been found that systemic SP-D is associated with metabolic disturbances and that SP-D deficient mice are mildly obese. However, the mechanism behind SP-D's role in energy metabolism is not known.Here we report that SP-D deficient mice had significantly higher ad libitum energy intake compared to wild-type mice and unchanged energy expenditure. This resulted in accumulation but also redistribution of fat tissue. Blood pressure was unchanged. The change in energy intake was unrelated to the basal levels of hypothalamic Pro-opiomelanocortin (POMC and Agouti-related peptide (AgRP gene expression. Neither short time systemic, nor intracereberoventricular SP-D treatment altered the hypothalamic signalling or body weight accumulation.In ad libitum fed animals, serum leptin, insulin, and glucose were significantly increased in mice deficient in SP-D, and indicative of insulin resistance. However, restricted diets eliminated all metabolic differences except the distribution of body fat. SP-D deficiency was further associated with elevated levels of systemic bacterial lipopolysaccharide.In conclusion, our findings suggest that lack of SP-D mediates modulation of food intake not directly involving hypothalamic regulatory pathways. The resulting accumulation of adipose tissue was associated with insulin resistance. The data suggest SP-D as a regulator of energy intake and body composition and an inhibitor of metabolic endotoxemia. SP-D may play a causal role at the crossroads of inflammation, obesity, and insulin resistance.

  3. Prioritizing Crop Management to Increase Nitrogen Use Efficiency in Australian Sugarcane Crops

    Directory of Open Access Journals (Sweden)

    Peter J. Thorburn

    2017-09-01

    Full Text Available Sugarcane production relies on the application of large amounts of nitrogen (N fertilizer. However, application of N in excess of crop needs can lead to loss of N to the environment, which can negatively impact ecosystems. This is of particular concern in Australia where the majority of sugarcane is grown within catchments that drain directly into the World Heritage listed Great Barrier Reef Marine Park. Multiple factors that impact crop yield and N inputs of sugarcane production systems can affect N use efficiency (NUE, yet the efficacy many of these factors have not been examined in detail. We undertook an extensive simulation analysis of NUE in Australian sugarcane production systems to investigate (1 the impacts of climate on factors determining NUE, (2 the range and drivers of NUE, and (3 regional variation in sugarcane N requirements. We found that the interactions between climate, soils, and management produced a wide range of simulated NUE, ranging from ∼0.3 Mg cane (kg N-1, where yields were low (i.e., <50 Mg ha-1 and N inputs were high, to >5 Mg cane (kg N-1 in plant crops where yields were high and N inputs low. Of the management practices simulated (N fertilizer rate, timing, and splitting; fallow management; tillage intensity; and in-field traffic management, the only practice that significantly influenced NUE in ratoon crops was N fertilizer application rate. N rate also influenced NUE in plant crops together with the management of the preceding fallow. In addition, there is regional variation in N fertilizer requirement that could make N fertilizer recommendations more specific. While our results show that complex interrelationships exist between climate, crop growth, N fertilizer rates and N losses to the environment, they highlight the priority that should be placed on optimizing N application rate and fallow management to improve NUE in Australian sugarcane production systems. New initiatives in seasonal climate forecasting

  4. Nitrogen fixation in boreal peatlands: the effects of increased N deposition on N2-fixation

    Science.gov (United States)

    Popma, J. M.; Wieder, R.; Lamers, L.; Vile, M. A.

    2013-12-01

    Boreal peatlands are of great importance to global carbon and nitrogen cycling. While covering only 3-4 % of the terrestrial surface, they account for 25-30 % of the world's soil C and 9-15 % of the world's soil N. In Western Canada atmospheric dry deposition rates are extremely low: approximately 1 kg N ha-1 yr-1. Though these systems have been functioning as net sinks over the past 11,000 years, natural and anthropogenic disturbances might compromise the historical balance of C and N. Biological N2-fixation has recently been shown to represent a very significant input of N into these systems, contributing to 62% of total N in Western Canada. Interactions between N deposition and biological N2-fixation are as yet, unknown, but the impact of elevated deposition of N-compounds from increased industrial expansion of oil sands mining to peatlands, is concerning. Given that nitrogenase, the enzyme responsible for catalyzing N2-fixation, is energetically costly when active, enhanced inputs of atmospheric N deposition could be a major determinant for enzyme activity and rates of biological N input to these bogs. Understanding interactions between N deposition and N2 fixation in boreal peatlands can aid in predicting the consequences of increased N deposition and setting critical loads. We conducted a field-fertilization experiment in a poor fen in Alberta, Canada, to determine the effects of enhanced N deposition on a dominant fen species Sphagnum angustifolium. The experiment consisted of seven N treatments: Control, 0, 5, 10, 15, 20 and 25 kg N ha-1 y1, n=3. N2-fixation was measured during summer 2012 and 2013 using the acetylene reduction assay (ARA). ARA rates were converted to rates of N2-fixation by calibrating ARA with paired 15N2-incubations. In both 2012 and 2013, with increasing N deposition from 0 kg N ha-1 yr-1 to 25 kg N ha-1 yr-1, rates of N2 fixation decreased, with highest rates in the 0 kg N ha-1 yr-1 treatment mosses (54.2 × 1.40; 48.58 × 7.12 kg N ha

  5. Is increase in bone mineral content caused by increase in skeletal muscle mass/strength in adult patients with GH-treated GH deficiency? A systematic literature analysis

    DEFF Research Database (Denmark)

    Klefter, O.; Feldt-Rasmussen, U.

    2009-01-01

    OBJECTIVE: Adult patients with GH deficiency (GHD) are characterized by a reduced muscle mass, but also reduced bone mineral density (BMD) and content (BMC), which have been ascribed to GHD per se. The aim of this study was to investigate if changes in BMD/BMC in adult GHD patients could be due...... performed a systematic literature analysis, including 51 clinical trials published between 1996 and 2008, which had studied the development in muscle mass, muscle strength, BMD, and/or BMC in GH-treated adult GHD patients. RESULTS: GH therapy had an anabolic effect on skeletal muscle. The largest increase...

  6. GPR40/FFAR1 deficient mice increase noradrenaline levels in the brain and exhibit abnormal behavior

    Directory of Open Access Journals (Sweden)

    Fuka Aizawa

    2016-12-01

    Full Text Available The free fatty acid receptor 1 (GPR40/FFAR1 is a G protein-coupled receptor, which is activated by long chain fatty acids. We have previously demonstrated that activation of brain GPR40/FFAR1 exerts an antinociceptive effect that is mediated by the modulation of the descending pain control system. However, it is unclear whether brain GPR40/FFAR1 contributes to emotional function. In this study, we investigated the involvement of GPR40/FFAR1 in emotional behavior using GPR40/FFAR1 deficient (knockout, KO mice. The emotional behavior in wild and KO male mice was evaluated at 9–10 weeks of age by the elevated plus-maze test, open field test, social interaction test, and sucrose preference test. Brain monoamines levels were measured using LC–MS/MS. The elevated plus-maze test and open field tests revealed that the KO mice reduced anxiety-like behavior. There were no differences in locomotor activity or social behavior between the wild and KO mice. In the sucrose preference test, the KO mice showed reduction in sucrose preference and intake. The level of noradrenaline was higher in the hippocampus, medulla oblongata, hypothalamus and midbrain of KO mice. Therefore, these results suggest that brain GPR40/FFAR1 is associated with anxiety- and depression-related behavior regulated by the increment of noradrenaline in the brain.

  7. Limitations of Improved Nitrogen Management to Reduce Nitrate Leaching and Increase Use Efficiency

    Directory of Open Access Journals (Sweden)

    James L. Baker

    2001-01-01

    Full Text Available The primary mode of nitrogen (N loss from tile-drained row-cropped land is generally nitrate-nitrogen (NO3-N leaching. Although cropping, tillage, and N management practices can be altered to reduce the amount of leaching, there are limits as to how much can be done. Data are given to illustrate the potential reductions for individual practices such as rate, method, and timing of N applications. However, most effects are multiplicative and not additive; thus it is probably not realistic to hope to get overall reductions greater than 25 to 30% with in-field practices alone. If this level of reduction is insufficient to meet water quality goals, additional off-site landscape modifications may be necessary.

  8. Soil Nematode Responses to Increases in Nitrogen Deposition and Precipitation in a Temperate Forest

    OpenAIRE

    Xiaoming Sun; Xiaoke Zhang; Shixiu Zhang; Guanhua Dai; Shijie Han; Wenju Liang

    2013-01-01

    The environmental changes arising from nitrogen (N) deposition and precipitation influence soil ecological processes in forest ecosystems. However, the corresponding effects of environmental changes on soil biota are poorly known. Soil nematodes are the important bioindicator of soil environmental change, and their responses play a key role in the feedbacks of terrestrial ecosystems to climate change. Therefore, to explore the responsive mechanisms of soil biota to N deposition and precipitat...

  9. Increased lipid production of the marine oleaginous microalgae Isochrysis zhangjiangensis (Chrysophyta) by nitrogen supplement.

    Science.gov (United States)

    Feng, Dina; Chen, Zhaoan; Xue, Song; Zhang, Wei

    2011-06-01

    Effects of nitrate feeding on the cell growth and lipid accumulation of marine microalgae Isochrysis zhangjiangensis were investigated. When nitrate was supplied at interval of 24h, instead of 72 h, a high lipid content of 40.9% and a biomass density of 3.1 g L(-1) were obtained. To confirm whether I. zhangjiangensis accumulates lipid during nitrogen-repletion, a two-stage cultivation method was applied. This algal strain had a high lipid content during sustained nitrate addition and showed a high carbohydrate content under nitrate-depletion conditions. These results revealed that this algal strain can accumulate lipids under nitrogen-repletion conditions and accumulate carbohydrate under nitrogen-depletion conditions. When cultured in an extremely high nitrate concentration, 9 g L(-1) at 24h intervals, the growth of algal cells was suppressed, but the highest lipid content of 53% was attained. This special characteristic of lipid accumulation makes I. zhangjiangensis an ideal candidate for producing biodiesel using N-rich wastewater.

  10. Rice straw incorporated just before soil flooding increases acetic acid formation and decreases available nitrogen

    Directory of Open Access Journals (Sweden)

    Ronaldir Knoblauch

    2014-02-01

    Full Text Available Incorporation of rice straw into the soil just before flooding for water-seeded rice can immobilize mineral nitrogen (N and lead to the production of acetic acid harmful to the rice seedlings, which negatively affects grain yield. This study aimed to evaluate the formation of organic acids and variation in pH and to quantify the mineral N concentration in the soil as a function of different times of incorporation of rice straw or of ashes from burning the straw before flooding. The experiment was carried out in a greenhouse using an Inceptisol (Typic Haplaquept soil. The treatments were as follows: control (no straw or ash; incorporation of ashes from previous straw burning; rice straw incorporated to drained soil 60 days before flooding; straw incorporated 30 days before flooding; straw incorporated 15 days before flooding and straw incorporated on the day of flooding. Experimental units were plastic buckets with 6.0 kg of soil. The buckets remained flooded throughout the trial period without rice plants. Soil samples were collected every seven days, beginning one day before flooding until the 13th week of flooding for determination of mineral N- ammonium (NH4+ and nitrate (NO3-. Soil solution pH and concentration of organic acids (acetic, propionic and butyric were determined. All NO3- there was before flooding was lost in approximately two weeks of flooding, in all treatments. There was sigmoidal behavior for NH4+ formation in all treatments, i.e., ammonium ion concentration began to rise shortly after soil flooding, slightly decreased and then went up again. On the 91st day of flooding, the NH4+ concentrations in soil was 56 mg kg-1 in the control treatment, 72 mg kg-1 for the 60-day treatment, 73 mg kg-1 for the 30-day treatment and 53 mg kg-1 for the ash incorporation treatment. These ammonium concentrations correspond to 84, 108, 110 and 80 kg ha-1 of N-NH4+, respectively. When the straw was incorporated on the day of flooding or 15 days

  11. Feed-derived volatile basic nitrogen increases reactive oxygen species production of blood leukocytes in lactating dairy cows.

    Science.gov (United States)

    Tsunoda, Ei; Gross, Josef J; Kawashima, Chiho; Bruckmaier, Rupert M; Kida, Katsuya; Miyamoto, Akio

    2017-01-01

    The present study investigated over 9 months the changes of fermentative quality of total mixed rations (TMR) containing grass silage (GS) as a major component, associated with changes in the volatile basic nitrogen (VBN) levels in an experimental dairy farm. Effects of VBN levels in TMR on metabolic parameters, reactive oxygen species (ROS) production by blood polymorphonuclear leukocytes (PMNs) and conception rates for dairy cows were analyzed. According to VBN levels in TMR during survey periods, three distinct phases were identified; phase A with low VBN; phase B with high VBN; and phase C with mid-VBN. Metabolic parameters in blood were all within normal range. However, during phases B and C, nitrogen metabolic indices such as blood urea nitrogen and milk urea nitrogen showed higher levels compared to those in phase A, and a simultaneous increase in ROS production by blood PMNs and the load on hepatic function in metabolic parameters was observed in the cows with a lower conception rate. This suggests that feeding TMR with elevated VBN levels due to poor fermented GS results in stimulation of ROS production by PMNs by ammonia, and negatively affects metabolism and reproductive performance in lactating dairy cow.

  12. Is increase in bone mineral content caused by increase in skeletal muscle mass/strength in adult patients with GH-treated GH deficiency?

    DEFF Research Database (Denmark)

    Klefter, Oliver; Feldt-Rasmussen, Ulla

    2009-01-01

    performed a systematic literature analysis, including 51 clinical trials published between 1996 and 2008, which had studied the development in muscle mass, muscle strength, BMD, and/or BMC in GH-treated adult GHD patients. RESULTS: GH therapy had an anabolic effect on skeletal muscle. The largest increase......OBJECTIVE: Adult patients with GH deficiency (GHD) are characterized by a reduced muscle mass, but also reduced bone mineral density (BMD) and content (BMC), which have been ascribed to GHD per se. The aim of this study was to investigate if changes in BMD/BMC in adult GHD patients could be due...... to a muscle modulating effect, and if treatment with GH would primarily increase muscle mass and strength with a secondary increase in BMD/BMC, thus supporting the present physiological concept that mass and strength of bones are mainly determined by dynamic loads from the skeletal muscles. METHOD: We...

  13. Does corticosteroid treatment cause prolonged recovery and increased total bilirubin level in severe ADAMTS-13-deficient TTP patient?

    Science.gov (United States)

    Sayiner, Zeynel Abidin; Acik, Didar Yanardag; Yilmaz, Mehmet; Subari, Salih; Mete, Ayse Ozlem; Dai, M Sinan

    2015-10-01

    A 41-year-old female patient complaining of fatigue, headache, mild confusion, and rush on her lower extremities was admitted to our emergency department. Laboratory tests revealed that he had anemia, thrombocytopenia, and increased levels of indirect bilirubin and lactic dehydrogenase (LDH) in blood tests. Direct and indirect Coombs tests were negative, and fragmented erythrocytes were observed in peripheral blood smears. The patient was diagnosed with thrombotic thrombocytopenic purpura (TTP). The best supportive care was provided. Therapeutic plasma exchange (TPE) and 1 mg/kg methylprednisolone treatments were administered. On the 10th day of treatment, LDH level and fragmented red blood cells in peripheral blood smear were decreased, but his direct and indirect bilirubin levels increased despite the fact that he was treated with 1 mg/kg methylprednisolone and TPE. The patient had severe ADAMTS-13 deficiency. After discontinued steroids treatment, his bilirubin level normalized within 4 days. On the 4th day after bilirubin level normalized, vincristine treatment was administered. TPE was also continued. There was no consensus about the optimal schedule for discontinuing plasmapheresis therapy, and also we observed total bilirubin level improvement with discontinued corticosteroid treatment. In this case, corticosteroid treatment was linked with the increase of total bilirubin level in severe ADAMTS-13-deficient TTP patient.

  14. Effects of increasing nitrogen concentration on the structure of carbon nitride films deposited by ion beam assisted deposition

    OpenAIRE

    Hammer, P.; Victoria, NM; F Alvarez

    2000-01-01

    Amorphous carbon nitride films containing increasing concentrations of nitrogen were deposited by ion beam assisted deposition at a substrate temperature of 150 degrees C. The relationship between the deposition conditions and the chemical bonding structure was investigated by x-ray photoelectron, ultraviolet photoelectron, infrared, and Raman spectroscopies. Film properties were examined by ultraviolet-vis spectroscopy, conductivity, hardness, density, and internal stress measurements. The e...

  15. A MULTISTAGE GRADUAL NITROGENREDUCTION STRATEGY FOR INCREASED LIPID PRODUCTIVITY AND NITROGEN REMOVAL IN WASTEWATER USING Chlorella vulgaris AND Scenedesmus obliquus

    Directory of Open Access Journals (Sweden)

    J. C. Robles-Heredia

    2015-06-01

    Full Text Available AbstractChlorella vulgaris and Scenedesmus obliquuswere grown in artificial-wastewater using a new nitrogen-limitation strategy aimed at increasing lipid productivity. This strategy consisted in a multi-stage process with sequential reduction of N-NH4 concentration (from 90 to 60, 40, and 20 mg.L-1 to promote a balance between cell growth and lipid accumulation. Lipid productivity was compared against a reference process consisting of nitrogen reduction in two stages, where the nitrogen concentration was suddenly reduced from 90 mg.L-1 to three different concentrations (10, 20, and 30 mg.L-1. In the multi-stage mode, only C. vulgaris exhibited a net lipid-productivity increase. Lipid content of S. obliquus did not present a significant increase, thus decreasing lipid productivity. The highest lipid productivities were observed in the two-stage mode for both S. obliquus and C. vulgaris (194.9 and 133.5 mg.L-1.d-1, respectively, and these values are among the highest reported in the literature to date.

  16. 分批补料及缺氮培养对小球藻油脂产量的影响%Effects of Fed-batch and Nitrogen-deficient Culture on Lipid Yield of Chlorella sp.

    Institute of Scientific and Technical Information of China (English)

    葛珍珍; 王杰; 余晓斌

    2012-01-01

    目的 为了实现小球藻的高密度及高产油培养。方法 通过分析分批培养过程中藻细胞的生长曲线,葡萄糖消耗曲线,pH及溶氧变化曲线,以小球藻进行分批补料,待藻细胞达到一定的高密度后再进行缺氮培养以富集细胞内的油脂。结果 经过4次分批补料,小球藻的生物量达到了65.25g/L,然后进行缺氮培养12h,然后进行缺氮培养12h,小球藻的油脂含量由42.75%提高到63.82%,油脂含量达43.47g/L.结论 合理的分批补料明显地提高了小球藻的生物量。缺氮培养进一步提高了小球藻的油脂含量。%[Objective] This study was to realize high-density culture of Chlorella sp. as well as the culture with high lipid yield. [Method] Through analyzing the growth curve of Chlorella sp. cells, dextrose consumption curve, change curves of pH and dissolved oxygen, a fed-batch culture was conducted, followed by a nitrogen-deficient culture aiming at accumulating the lipids in Chlorella sp. cells when a high density of Chlorella sp. cells was obtained. [Result] After four batches of feeding were pro- vided, the biomass of Chlorella sp. reached up to 65.25 g/L, and the lipid content increased from 42.75% to 63.82% in Chlorella sp. cells, with the yield of 43.37 g/L in the following 12 hours of nitrogen-deficient culture. [Conclusion] Reasonable fed- batch can significantly improve the biomass of Chlorella sp., and the nitrogen-defi- cient culture further raises the lipid yield of Chlorella sp.

  17. Alpha 1,3-Galactosyltransferase Deficiency in Pigs Increases Sialyltransferase Activities That Potentially Raise Non-Gal Xenoantigenicity

    Directory of Open Access Journals (Sweden)

    Jong-Yi Park

    2011-01-01

    Full Text Available We examined whether deficiency of the GGTA1 gene in pigs altered the expression of several glycosyltransferase genes. Real-time RT-PCR and glycosyltransferase activity showed that 2 sialyltransferases [α2,3-sialyltransferase (α2,3ST and α2,6-sialyltransferase (α2,6ST] in the heterozygote GalT KO liver have higher expression levels and activities compared to controls. Enzyme-linked lectin assays indicated that there were also more sialic acid-containing glycoconjugate epitopes in GalT KO livers than in controls. The elevated level of sialic-acid-containing glycoconjugate epitopes was due to the low level of α-Gal in heterozygote GalT KO livers. Furthermore, proteomics analysis showed that heterozygote GalT KO pigs had a higher expression of NAD+-isocitrate dehydrogenase (IDH, which is related to the CMP-N-acetylneuraminic acid hydroxylase (CMAH enzyme reaction. These findings suggest the deficiency of GGTA1 gene in pigs results in increased production of N-glycolylneuraminic acid (Neu5Gc due to an increase of α2,6-sialyltransferase and a CMAH cofactor, NAD+-IDH. This indicates that Neu5Gc may be a critical xenoantigen. The deletion of the CMAH gene in the GalT KO background is expected to further prolong xenograft survival.

  18. Soil nematode responses to increases in nitrogen deposition and precipitation in a temperate forest.

    Science.gov (United States)

    Sun, Xiaoming; Zhang, Xiaoke; Zhang, Shixiu; Dai, Guanhua; Han, Shijie; Liang, Wenju

    2013-01-01

    The environmental changes arising from nitrogen (N) deposition and precipitation influence soil ecological processes in forest ecosystems. However, the corresponding effects of environmental changes on soil biota are poorly known. Soil nematodes are the important bioindicator of soil environmental change, and their responses play a key role in the feedbacks of terrestrial ecosystems to climate change. Therefore, to explore the responsive mechanisms of soil biota to N deposition and precipitation, soil nematode communities were studied after 3 years of environmental changes by water and/or N addition in a temperate forest of Changbai Mountain, Northeast China. The results showed that water combined with N addition treatment decreased the total nematode abundance in the organic horizon (O), while the opposite trend was found in the mineral horizon (A). Significant reductions in the abundances of fungivores, plant-parasites and omnivores-predators were also found in the water combined with N addition treatment. The significant effect of water interacted with N on the total nematode abundance and trophic groups indicated that the impacts of N on soil nematode communities were mediated by water availability. The synergistic effect of precipitation and N deposition on soil nematode communities was stronger than each effect alone. Structural equation modeling suggested water and N additions had direct effects on soil nematode communities. The feedback of soil nematodes to water and nitrogen addition was highly sensitive and our results indicate that minimal variations in soil properties such as those caused by climate changes can lead to severe changes in soil nematode communities.

  19. Nitrogen decreases and precipitation increases ectomycorrhizal extramatrical mycelia production in a longleaf pine forest.

    Science.gov (United States)

    Sims, Stephanie E; Hendricks, Joseph J; Mitchell, Robert J; Kuehn, Kevin A; Pecot, Stephen D

    2007-06-01

    The rates and controls of ectomycorrhizal fungal production were assessed in a 22-year-old longleaf pine (Pinus palustris Mill.) plantation using a complete factorial design that included two foliar scorching (control and 95% plus needle scorch) and two nitrogen (N) fertilization (control and 5 g N m(-2) year(-1)) treatments during an annual assessment. Ectomycorrhizal fungi production comprised of extramatrical mycelia, Hartig nets and mantles on fine root tips, and sporocarps was estimated to be 49 g m(-2) year(-1) in the control treatment plots. Extramatrical mycelia accounted for approximately 95% of the total mycorrhizal production estimate. Mycorrhizal production rates did not vary significantly among sample periods throughout the annual assessment (p = 0.1366). In addition, reduction in foliar leaf area via experimental scorching treatments did not influence mycorrhizal production (p = 0.9374), suggesting that stored carbon (C) may decouple the linkage between current photosynthate production and ectomycorrhizal fungi dynamics in this forest type. Nitrogen fertilization had a negative effect, whereas precipitation had a positive effect on mycorrhizal fungi production (p = 0.0292; r (2) = 0.42). These results support the widely speculated but poorly documented supposition that mycorrhizal fungi are a large and dynamic component of C flow and nutrient cycling dynamics in forest ecosystems.

  20. Increased depression-like behaviors in corticotropin-releasing factor receptor-2-deficient mice: sexually dichotomous responses.

    Science.gov (United States)

    Bale, Tracy L; Vale, Wylie W

    2003-06-15

    Depressive disorders affect nearly 19 million American adults, making depression and the susceptibility for developing depression a critical focus of mental health research today. Females are twice as likely to develop depression as males. Stress is a known risk factor for developing depression, and recent hypotheses suggest an involvement of an overactive stress axis. As mediators of the stress response, corticotropin-releasing factor (CRF) and its receptors (CRFR1 and CRFR2) have been implicated in the propensity for developing stress-related mood disorders. Mice deficient in CRFR2 display increased anxiety-like behaviors and a hypersensitive stress response. As a possible animal model of depression, these mice were tested for depression-like behaviors in the forced swim test. Comparisons were made between wild-type and mutant animals, as well as between sexes. Male and female CRFR2-mutant mice showed increased immobility as an indicator of depression compared with wild-type mice of the same sex. In addition, mutant and wild-type female mice demonstrated increased immobile time compared with males of the same genotype. Treatment of CRFR2-deficient mice with the CRFR1 antagonist antalarmin decreased immobile time and increased swim time in both sexes. We found a significant effect of sex for both time spent immobile and swimming after antalarmin treatment. Because differences in behaviors in the forced swim test are good indicators of serotonergic and catecholaminergic involvement, our results may reveal an interaction of CRF pathways with other known antidepressant systems and may also support an involvement of CRF receptors in the development of depression such that elevated CRFR1 activity, in the absence of CRFR2, increases depression-like behaviors.

  1. Nitrogen Fertilization Increases Litter Production and Nutrient Resorption Efficiency of Castanopsis eyrei In a Subtropical Forest, China

    Science.gov (United States)

    Tian, D.

    2015-12-01

    Anthropogenic activities has enhanced nitrogen (N) deposition globally, decoupling the biogeochemical cycles and exhibiting a profound influences on carbon sequestration across terrestrial ecosystems. The responses of plant productivity and nutrient cycling to nitrogen deposition have been widely reported in forests across Euro-America, but with little evidence from subtropical forest ecosystem across China. Here we conducted a nitrogen fertilization experiment in a nature subtropical forest in southeast China for more than four years, and investigated the induced changes in litter production, leaf N and P concentrations and resorption efficiency of Castanopsis eyrei, as the dominate species in most subtropical evergreen forests in China. Results showed that N fertilization increased litter production, which performed a concurrent seasonal pattern with peak defoliation in spring and autumn. N fertilization significantly increased N and P concentrations in green and senesced leaves, and the leaf N and P resorption efficiencies. In contrast to the predominant results across temperate and tropical ecosystems, our findings reveal a distinguishable pattern of resorption efficiencies in respond to nutrient changes, and highlight that regional characteristic and spatial heterogeneity should be considered when predicting future impacts of N deposition on plant growth and nutrient cycling.

  2. Increased numbers of mast cells in the hyperplastic buccal mucosa of the zinc-deficient rat.

    Science.gov (United States)

    Kreavich, M E; Meyer, J; Waterhouse, J P

    1981-02-01

    Six weanling male Sprague Dawley rats were fed a diet containing 0.4 ppm Zn and seven were fed an identical diet except for 40 ppm Zn. After 4 weeks, specimens of buccal mucosa in the region facing the molar teeth were removed. Paraffin sections, cut at 6 micron, were stained with toluidine blue, and tracings made of five sections per animal, spaced no less than 60 micron apart. Counts of mast cells of five sections length of section were made in a superficial zone of the lamina propria of 50 micron width and a deeper zone of 250 micron width. The average number of mast cells, per mm in the subepithelial zone of the experimental animals was 15.4, the range 9.2-33.1. The control average was 4.0; the range was 2.9-5.3. No increase was found in the deeper zone. The epithelium was parakeratotic and its thickness was increased two-fold. In the peripheral portion of the section, cellular and keratin layers were evenly increased in thickness, but in the central portion a disproportionate, nearly four-fold increase occurred in the keratin layer and a lesser increase in the cellular layer.

  3. Type I and III procollagen propeptides in growth hormone-deficient patients: effects of increasing doses of GH

    DEFF Research Database (Denmark)

    Jensen, L T; Jørgensen, J O; Risteli, J;

    1991-01-01

    The effect of increasing doses of growth hormone on collagen synthesis in GH-treated GH-deficient patients was determined in a short-term study. The synthesis of type I and III collagen was estimated by measurements of the carboxyterminal propeptide of type I procollagen and the aminoterminal...... propeptide of type III procollagen. Type I collagen is mainly found in bone and type III collagen in loose connective tissue. We observed a GH dose dependency of both procollagen propeptides. Serum type I procollagen propeptide was significantly higher following GH doses of 4 and 6 IU/day for 14 days...... procollagen propeptide increased twice as much as type I procollagen propeptide, by 47 vs 25%, at a GH dose of 6 IU/day compared with 2 IU/day. The differences between the effects on type I and type III collagen may reflect differences in secretion or turn-over rate of collagen in bone and loose connective...

  4. Metallothionein-1+2 deficiency increases brain pathology in transgenic mice with astrocyte-targeted expression of interleukin 6

    DEFF Research Database (Denmark)

    Giralt, Mercedes; Penkowa, Milena; Hernández, Joaquín

    2002-01-01

    ) mice provided evidence that the increased MT-1+2 expression normally observed in the GFAP-IL6 mice is an important mechanism for coping with brain damage. Thus, the GFAP-IL6xMTKO mice showed a decreased body weight gain and an impaired performance in the rota-rod test, as well as a higher upregulation...... of cytokines such as IL-6, IL-1alpha,beta, and TNFalpha and recruitment and activation of macrophages and T cells throughout the CNS but mainly in the cerebellum. Clear symptoms of increased oxidative stress and apoptotic cell death caused by MT-1+2 deficiency were observed in the GFAP-IL6xMTKO mice...

  5. Overweight increases risk of trimester hypothyroxinaemia in iodine-deficient pregnant woman

    NARCIS (Netherlands)

    Gowachirapant, S.; Boonstra, A.; Winichagoon, P.; Zimmerman, M.B.

    2014-01-01

    Hypothyroxinaemia early in pregnancy may impair fetal brain development. Increased body weight has been associated with low thyroxine concentrations in non-pregnant women. In pregnant women, morbid maternal obesity is a risk factor for thyroid dysfunction. But whether lesser degrees of overweight th

  6. Serotonin Transporter Deficiency Increases Abdominal Fat in Female, but Not Male Rats

    NARCIS (Netherlands)

    Homberg, J.R.; la Fleur, S.E.; Cuppen, E.

    2010-01-01

    Depression and abdominal obesity often co-occur, predominantly in women, and are associated with an increased risk for the development of glucose intolerance and subsequently type 2 diabetes. The underlying mechanisms are poorly understood. We found that female, but not male, depression-prone seroto

  7. Overweight increases risk of trimester hypothyroxinaemia in iodine-deficient pregnant woman

    NARCIS (Netherlands)

    Gowachirapant, S.; Boonstra, A.; Winichagoon, P.; Zimmerman, M.B.

    2014-01-01

    Hypothyroxinaemia early in pregnancy may impair fetal brain development. Increased body weight has been associated with low thyroxine concentrations in non-pregnant women. In pregnant women, morbid maternal obesity is a risk factor for thyroid dysfunction. But whether lesser degrees of overweight

  8. Overweight increases risk of trimester hypothyroxinaemia in iodine-deficient pregnant woman

    NARCIS (Netherlands)

    Gowachirapant, S.; Boonstra, A.; Winichagoon, P.; Zimmerman, M.B.

    2014-01-01

    Hypothyroxinaemia early in pregnancy may impair fetal brain development. Increased body weight has been associated with low thyroxine concentrations in non-pregnant women. In pregnant women, morbid maternal obesity is a risk factor for thyroid dysfunction. But whether lesser degrees of overweight th

  9. Serotonin transporter deficiency increases abdominal fat in female, but not male rats

    NARCIS (Netherlands)

    J.R. Homberg; S.E. la Fleur; E. Cuppen

    2010-01-01

    Depression and abdominal obesity often co-occur, predominantly in women, and are associated with an increased risk for the development of glucose intolerance and subsequently type 2 diabetes. The underlying mechanisms are poorly understood. We found that female, but not male, depression-prone seroto

  10. ATP6v0d2 Deficiency Increases Bone Mass, but Does Not Influence Ovariectomy-Induced Bone Loss

    Science.gov (United States)

    Kim, Taesoo; Ha, Hyunil; Kim, Nacksung; Park, Eui-Soon; Rho, Jaerang; Kim, Eun Cheol; Lorenzo, Joseph; Choi, Yongwon; Lee, Seoung Hoon

    2010-01-01

    Bone homeostasis is maintained through the balanced action of bone-forming osteoblasts and bone-resorbing osteoclasts. Under pathological conditions or with age, excessive bone loss is often observed due to increased bone resorption. Since osteoclasts are the primary cells in the body that can resorb bone, molecular understanding of osteoclast fate has important clinical implications. Over the past twenty years, many molecular players that govern osteoclast differentiation during normal development have been identified. However, whether the same molecules regulate bone loss occurring under pathological conditions remains largely unknown. We report here that although ATP6v0d2-deficient (ATP6v0d2 KO) mice exhibit an osteopetrotic phenotype due to inefficient osteoclast maturation, this deficiency fails to protect mice from ovariectomy (OVX)-induced bone loss, a model for post-menopause-associated osteoporosis. Moreover, we show that an OVX-induced increase in the number of colony forming unit-granulocyte/macrophage (CFU-GM) in bone marrow cells and subsequent osteoclast formation in vitro was not affected in the absence of ATP6v0d2. However, even after OVX, formation of large osteoclasts (> 100 μm in diameter) with actin rings was still reduced in the absence of ATP6v0d2. Taken together, these findings suggest that the critical role of ATP6v0d2 may be limited to the control of bone homeostasis under normal development, and that OVX-induced bone loss is likely to be governed mostly by the increase in osteoclast precursors rather than increased efficiency of osteoclast maturation. PMID:21040703

  11. Histamine deficiency exacerbates myocardial injury in acute myocardial infarction through impaired macrophage infiltration and increased cardiomyocyte apoptosis.

    Science.gov (United States)

    Deng, Long; Hong, Tao; Lin, Jinyi; Ding, Suling; Huang, Zheyong; Chen, Jinmiao; Jia, Jianguo; Zou, Yunzeng; Wang, Timothy C; Yang, Xiangdong; Ge, Junbo

    2015-08-17

    Histamine is a biogenic amine that is widely distributed and has multiple functions, but the role it plays in acute myocardial infarction (AMI) remains unclear. In this study, we investigated the origin and contribution of endogenous histamine to AMI. Histidine decarboxylase (HDC) is the unique enzyme responsible for histamine generation. Using HDC-EGFP bacterial artificial chromosome (BAC) transgenic mice in which EGFP expression is controlled by the HDC promoter, we identified HDC expression primarily in CD11b(+)Gr-1(+) immature myeloid cells (IMCs) that markedly increase in the early stages of AMI. Deficiency of histamine in HDC knockout mice (HDC(-/-)) reduced cardiac function and exacerbated the injury of infarcted heart. Furthermore, administering either an H1 receptor antagonist (pyrilamine) or an H2 receptor antagonist (cimetidine) demonstrated a protective effect of histamine against myocardial injury. The results of in vivo and in vitro assays showed that histamine deficiency promotes the apoptosis of cardiomyocytes and inhibits macrophage infiltration. In conclusion, CD11b(+)Gr-1(+) IMCs are the predominant HDC-expressing sites in AMI, and histamine plays a protective role in the process of AMI through inhibition of cardiomyocyte apoptosis and facilitation of macrophage infiltration.

  12. Increasing thermal drying temperature of biosolids reduced nitrogen mineralisation and soil N2O emissions

    DEFF Research Database (Denmark)

    Case, Sean; Gomez Muñoz, Beatriz; Magid, Jakob

    2016-01-01

    Previous studies found that thermally dried biosolids contained more mineralisable organic nitrogen (N) than the raw or anaerobically digested (AD) biosolids they were derived from. However, the effect of thermal drying temperature on biosolid N availability is not well understood....... This will be of importance for the value of the biosolids when used to fertilise crops. We sourced AD biosolids from a Danish waste water treatment plant (WWTP) and dried it in the laboratory at 70, 130, 190 or 250 °C to >95 % dry matter content. Also, we sourced biosolids from the WWTP dried using its in-house thermal...... drying process (input temperature 95 °C, thermal fluid circuit temperature 200 °C, 95 % dry matter content). The drying process reduced the ammonium content of the biosolids and reduced it further at higher drying temperatures. These findings were attributed to ammonia volatilisation. The percentage...

  13. Soil nematode responses to increases in nitrogen deposition and precipitation in a temperate forest.

    Directory of Open Access Journals (Sweden)

    Xiaoming Sun

    Full Text Available The environmental changes arising from nitrogen (N deposition and precipitation influence soil ecological processes in forest ecosystems. However, the corresponding effects of environmental changes on soil biota are poorly known. Soil nematodes are the important bioindicator of soil environmental change, and their responses play a key role in the feedbacks of terrestrial ecosystems to climate change. Therefore, to explore the responsive mechanisms of soil biota to N deposition and precipitation, soil nematode communities were studied after 3 years of environmental changes by water and/or N addition in a temperate forest of Changbai Mountain, Northeast China. The results showed that water combined with N addition treatment decreased the total nematode abundance in the organic horizon (O, while the opposite trend was found in the mineral horizon (A. Significant reductions in the abundances of fungivores, plant-parasites and omnivores-predators were also found in the water combined with N addition treatment. The significant effect of water interacted with N on the total nematode abundance and trophic groups indicated that the impacts of N on soil nematode communities were mediated by water availability. The synergistic effect of precipitation and N deposition on soil nematode communities was stronger than each effect alone. Structural equation modeling suggested water and N additions had direct effects on soil nematode communities. The feedback of soil nematodes to water and nitrogen addition was highly sensitive and our results indicate that minimal variations in soil properties such as those caused by climate changes can lead to severe changes in soil nematode communities.

  14. Increased osteopontin contributes to inhibition of bone mineralization in FGF23-deficient mice.

    Science.gov (United States)

    Yuan, Quan; Jiang, Yan; Zhao, Xuefeng; Sato, Tadatoshi; Densmore, Michael; Schüler, Christiane; Erben, Reinhold G; McKee, Marc D; Lanske, Beate

    2014-03-01

    Excessive FGF23 has been identified as a pivotal phosphaturic factor leading to renal phosphate-wasting and the subsequent development of rickets and osteomalacia. In contrast, loss of FGF23 in mice (Fgf23(-/-) ) leads to high serum phosphate, calcium, and 1,25-vitamin D levels, resulting in early lethality attributable to severe ectopic soft-tissue calcifications and organ failure. Paradoxically, Fgf23(-/-) mice exhibit a severe defect in skeletal mineralization despite high levels of systemic mineral ions and abundant ectopic mineralization, an abnormality that remains largely unexplained. Through use of in situ hybridization, immunohistochemistry, and immunogold labeling coupled with electron microscopy of bone samples, we discovered that expression and accumulation of osteopontin (Opn/OPN) was markedly increased in Fgf23(-/-) mice. These results were confirmed by qPCR analyses of Fgf23(-/-) bones and ELISA measurements of serum OPN. To investigate whether elevated OPN levels were contributing to the bone mineralization defect in Fgf23(-/-) mice, we generated Fgf23(-/-) /Opn(-/-) double-knockout mice (DKO). Biochemical analyses showed that the hypercalcemia and hyperphosphatemia observed in Fgf23(-/-) mice remained unchanged in DKO mice; however, micro-computed tomography (µCT) and histomorphometric analyses showed a significant improvement in total mineralized bone volume. The severe osteoidosis was markedly reduced and a normal mineral apposition rate was present in DKO mice, indicating that increased OPN levels in Fgf23(-/-) mice are at least in part responsible for the osteomalacia. Moreover, the increased OPN levels were significantly decreased upon lowering serum phosphate by feeding a low-phosphate diet or after deletion of NaPi2a, indicating that phosphate levels contribute in part to the high OPN levels in Fgf23(-/-) mice. In summary, our results suggest that increased OPN is an important pathogenic factor mediating the mineralization defect and the

  15. CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a

    Directory of Open Access Journals (Sweden)

    Rachel Vaivoda

    2015-01-01

    Full Text Available CYP4Fs were first identified as enzymes that catalyze hydroxylation of leukotriene B4 (LTB4. CYP4F18 has an unusual expression in neutrophils and was predicted to play a role in regulating LTB4-dependent inflammation. We compared chemotaxis of wild-type and Cyp4f18 knockout neutrophils using an in vitro assay. There was no significant difference in the chemotactic response to LTB4, but the response to complement component C5a increased 1.9–2.25-fold in knockout cells compared to wild-type (P < 0.01. This increase was still observed when neutrophils were treated with inhibitors of eicosanoid synthesis. There were no changes in expression of other CYP4 enzymes in knockout neutrophils that might compensate for loss of CYP4F18 or lead to differences in activity. A mouse model of dextran sodium sulfate colitis was used to investigate the consequences of increased C5a-dependent chemotaxis in vivo, but there was no significant difference in weight loss, disease activity, or colonic tissue myeloperoxidase between wild-type and Cyp4f18 knockout mice. This study demonstrates the limitations of inferring CYP4F function based on an ability to use LTB4 as a substrate, points to expanding roles for CYP4F enzymes in immune regulation, and underscores the in vivo challenges of CYP knockout studies.

  16. Seipin deficiency increases chromocenter fragmentation and disrupts acrosome formation leading to male infertility.

    Science.gov (United States)

    El Zowalaty, A E; Baumann, C; Li, R; Chen, W; De La Fuente, R; Ye, X

    2015-07-16

    The Berardinelli-Seip congenital lipodystrophy type 2 (Bscl2, seipin) gene is involved in adipogenesis. Bscl2-/- males were infertile but had normal mating behavior. Both Bscl2-/- cauda epididymis sperm count and sperm motility were ~20×less than control. Bscl2-/- seminiferous tubules had relatively normal presence of spermatogonia and spermatocytes but had reduced spermatids and sperm. Spatiotemporal expression analyses in Bscl2+/+ testes demonstrated prominent Bscl2 transcriptional activity in spermatocytes with a plateau reached around postnatal day 28. Seipin protein localization was most abundant in postmeiotic spermatids, suggesting translational repression of Bscl2 mRNA in spermatocytes. In situ end-labeling plus detected increased spermatid apoptosis in Bscl2-/- testis and annexin V detected increased percentage of positive Bscl2-/- round spermatids compared with control. Immunofluorescence of marker proteins synaptonemal complex proteins 3 and 1 (SYCP3 and SYCP1), and H3K9me3 (histone H3 trimethylated at lysine 9) in germ cell spreads detected normal meiotic chromosome pairing and homologous chromosome synapsis in Bscl2-/- spermatocytes, but significantly increased percentages of round spermatids with chromocenter fragmentation and late spermatids and sperm with chromatin vacuoles, indicating defective chromatin condensation in Bscl2-/- spermatids. Bscl2-/- late spermatids were disorganized within the seminiferous epithelium, despite normal appearance of Sertoli cells detected by vimentin immunofluorescence. Peanut agglutinin staining revealed various abnormalities of acrosomes in Bscl2-/- late spermatids, including the absence, irregular-shaped, and fragmented acrosomes, indicating defective acrosome formation in Bscl2-/- late spermatids, which may affect late spermatid orientation in the seminiferous epithelium. Mitotracker strongly stained the midpiece of control sperm but only very weakly labeled the midpiece of Bscl2-/- sperm, indicating defective

  17. Nitrogen-Deficiency Stress Induces Protein Expression Differentially in Low-N Tolerant and Low-N Sensitive Maize Genotypes

    Science.gov (United States)

    Nazir, Muslima; Pandey, Renu; Siddiqi, Tariq O.; Ibrahim, Mohamed M.; Qureshi, Mohammad I.; Abraham, Gerard; Vengavasi, Krishnapriya; Ahmad, Altaf

    2016-01-01

    Nitrogen (N) is essential for proper plant growth and its application has proven to be critical for agricultural produce. However, for unavoidable economic and environmental problems associated with excessive use of N-fertilizers, it is an urgent demand to manage application of fertilizers. Improving the N-use efficiency (NUE) of crop plants to sustain productivity even at low N levels is the possible solution. In the present investigation, contrasting low-N sensitive (HM-4) and low-N tolerant (PEHM-2) genotypes were identified and used for comparative proteome-profiling of leaves under optimum and low N as well as restoration of low N on 3rd (NR3) and 5th (NR5) days after re-supplying N. The analysis of differential expression pattern of proteins was performed by 2-D gel electrophoresis. Significant variations in the expression of proteins were observed under low N, which were genotype specific. In the leaf proteome, 25 spots were influenced by N treatment and four spots were different between the two genotypes. Most of the proteins that were differentially accumulated in response to N level and were involved in photosynthesis and metabolism, affirming the relationship between N and carbon metabolism. In addition to this, greater intensity of some defense proteins in the low N tolerant genotype was found that may have a possible role in imparting it tolerance under N starvation conditions. The new insights generated on maize proteome in response to N-starvation and restoration would be useful toward improvement of NUE in maize. PMID:27047497

  18. Glucagon-producing cells are increased in Mas-deficient mice.

    Science.gov (United States)

    Felix Braga, Janaína; Ravizzoni Dartora, Daniela; Alenina, Natalia; Bader, Michael; Santos, Robson Augusto Souza

    2017-01-01

    It has been shown that angiotensin(1-7) (Ang(1-7)) produces several effects related to glucose homeostasis. In this study, we aimed to investigate the effects of genetic deletion of Ang(1-7), the GPCR Mas, on the glucagon-producing cells. C57BL6/N Mas(-/-) mice presented a significant and marked increase in pancreatic α-cells (number of cells: 146 ± 21 vs 67 ± 8 in WT; P Mas(-/-) mice (0.25 ± 0.01 vs 0.31 ± 56.45 pg/mL in WT; P = 0.02). In order to eliminate the possibility of a background-related phenotype, we determined the number of glucagon-producing cells in FVB/N Mas(-/-) mice. In keeping with the observations in C57BL6/N Mas(-/-) mice, the number and percentage of pancreatic α-cells were also significantly increased in these mice (number of α-cells: 260 ± 22 vs 156 ± 12 in WT, P Mas has a previously unexpected role on the pancreatic glucagon production. © 2017 The authors.

  19. Gas6 increases myelination by oligodendrocytes and its deficiency delays recovery following cuprizone-induced demyelination.

    Directory of Open Access Journals (Sweden)

    Michele D Binder

    Full Text Available Multiple sclerosis (MS is a complex demyelinating disease of the central nervous system. Current research has shown that at least in some cases, the primary insult in MS could be directed at the oligodendrocyte, and that the earliest immune responses are primarily via innate immune cells. We have identified a family of receptor protein tyrosine kinases, known as the TAM receptors (Tyro3, Axl and Mertk, as potentially important in regulating both the oligodendrocyte and immune responses. We have previously shown that Gas6, a ligand for the TAM receptors, can affect the severity of demyelination in mice, with a loss of signalling via Gas6 leading to decreased oligodendrocyte survival and increased microglial activation during cuprizone-induced demyelination. We hypothesised TAM receptor signalling would also influence the extent of recovery in mice following demyelination. A significant effect of the absence of Gas6 was detected upon remyelination, with a lower level of myelination after 4 weeks of recovery in comparison with wild-type mice. The delay in remyelination was accompanied by a reduction in oligodendrocyte numbers. To understand the molecular mechanisms that drive the observed effects, we also examined the effect of exogenous Gas6 in in vitro myelination assays. We found that Gas6 significantly increased myelination in a dose-dependent manner, suggesting that TAM receptor signalling could be directly involved in myelination by oligodendrocytes. The reduced rate of remyelination in the absence of Gas6 could thus result from a lack of Gas6 at a critical time during myelin production after injury. These findings establish Gas6 as an important regulator of both CNS demyelination and remyelination.

  20. Effects of Bleaching by Nitrogen Deficiency on the Quantum Yield of Photosystem II in Synechocystis sp. PCC 6803 Revealed by Chl Fluorescence Measurements.

    Science.gov (United States)

    Ogawa, Takako; Sonoike, Kintake

    2016-03-01

    Estimation of photosynthesis by Chl fluorescence measurement of cyanobacteria is always problematic due to the interference from respiratory electron transfer and from phycocyanin fluorescence. The interference from respiratory electron transfer could be avoided by the use of DCMU or background illumination by blue light, which oxidizes the plastoquinone pool that tends to be reduced by respiration. On the other hand, the precise estimation of photosynthesis in cells with a different phycobilisome content by Chl fluorescence measurement is difficult. By subtracting the basal fluorescence due to the phycobilisome and PSI, it becomes possible to estimate the precise maximum quantum yield of PSII in cyanobacteria. Estimated basal fluorescence accounted for 60% of the minimum fluorescence, resulting in a large difference between the 'apparent' yield and 'true' yield under high phycocyanin conditions. The calculated value of the 'true' maximum quantum yield of PSII was around 0.8, which was similar to the value observed in land plants. The results suggest that the cause of the apparent low yield reported in cyanobacteria is mainly ascribed to the interference from phycocyanin fluorescence. We also found that the 'true' maximum quantum yield of PSII decreased under nitrogen-deficient conditions, suggesting the impairment of the PSII reaction center, while the 'apparent' maximum quantum yield showed a marginal change under the same conditions. Due to the high contribution of phycocyanin fluorescence in cyanobacteria, it is essential to eliminate the influence of the change in phycocyanin content on Chl fluorescence measurement and to evaluate the 'true' photosynthetic condition.

  1. CD22 x Siglec-G double-deficient mice have massively increased B1 cell numbers and develop systemic autoimmunity.

    Science.gov (United States)

    Jellusova, Julia; Wellmann, Ute; Amann, Kerstin; Winkler, Thomas H; Nitschke, Lars

    2010-04-01

    CD22 and Siglec-G are inhibitory coreceptors for BCR-mediated signaling. Although CD22-deficient mice show increased calcium signaling in their conventional B2 cells and a quite normal B cell maturation, Siglec-G-deficient mice have increased calcium mobilization just in B1 cells and show a large expansion of the B1 cell population. Neither CD22-deficient, nor Siglec-G-deficient mice on a pure C57BL/6 or BALB/c background, respectively, develop autoimmunity. Using Siglec-G x CD22 double-deficient mice, we addressed whether Siglec-G and CD22 have redundant functions. Siglec-G x CD22 double-deficient mice show elevated calcium responses in both B1 cells and B2 cells, increased serum IgM levels and an enlarged population of B1 cells. The enlargement of B1 cell numbers is even higher than in Siglecg(-/-) mice. This expansion seems to happen at the expense of B2 cells, which are reduced in absolute cell numbers, but show an activated phenotype. Furthermore, Siglec-G x CD22 double-deficient mice show a diminished immune response to both thymus-dependent and thymus-independent type II Ags. In contrast, B cells from Siglec-G x CD22 double-deficient mice exhibit a hyperproliferative response to stimulation with several TLR ligands. Aged Siglec-G x CD22 double-deficient mice spontaneously develop anti-DNA and antinuclear autoantibodies. These resulted in a moderate form of immune complex glomerulonephritis. These results show that Siglec-G and CD22 have partly compensatory functions and together are crucial in maintaining the B cell tolerance.

  2. Increased susceptibility to otitis media in a Splunc1-deficient mouse model

    Science.gov (United States)

    Bartlett, Jennifer A.; Meyerholz, David K.; Wohlford-Lenane, Christine L.; Naumann, Paul W.; Salzman, Nita H.; McCray, Paul B.

    2015-01-01

    ABSTRACT Otitis media (inflammation of the middle ear) is one of the most common diseases of early childhood. Susceptibility to otitis is influenced by a number of factors, including the actions of innate immune molecules secreted by the epithelia lining the nasopharynx, middle ear and Eustachian tube. The SPLUNC1 (short palate, lung, nasal epithelial clone 1) protein is a highly abundant secretory product of the mammalian nasal, oral and respiratory mucosa that is thought to play a multifunctional role in host defense. In this study we investigated Splunc1 expression in the ear of the mouse, and examined whether this protein contributes to overall host defense in the middle ear and/or Eustachian tube. We found that Splunc1 is highly expressed in both the surface epithelium and in submucosal glands in these regions in wild-type mice. In mice lacking Splunc1, we noted histologically an increased frequency of otitis media, characterized by the accumulation of leukocytes (neutrophils with scattered macrophages), proteinaceous fluid and mucus in the middle ear lumens. Furthermore, many of these mice had extensive remodeling of the middle ear wall, suggesting a chronic course of disease. From these observations, we conclude that loss of Splunc1 predisposes mice to the development of otitis media. The Splunc1−/− mouse model should help investigators to better understand both the biological role of Splunc1 as well as host defense mechanisms in the middle ear. PMID:25765466

  3. Nitrogen deposition and management practices increase soil microbial biomass carbon but decrease diversity in Moso bamboo plantations.

    Science.gov (United States)

    Li, Quan; Song, Xinzhang; Gu, Honghao; Gao, Fei

    2016-06-15

    Because microbial communities play a key role in carbon (C) and nitrogen (N) cycling, changes in the soil microbial community may directly affect ecosystem functioning. However, the effects of N deposition and management practices on soil microbes are still poorly understood. We studied the effects of these two factors on soil microbial biomass carbon (MBC) and community composition in Moso bamboo plantations using high-throughput sequencing of the 16S rRNA gene. Plantations under conventional (CM) or intensive management (IM) were subjected to one of four N treatments for 30 months. IM and N addition, both separately and in combination, significantly increased soil MBC while decreasing bacterial diversity. However, increases in soil MBC were inhibited when N addition exceeded 60 kg N∙ha(-1)∙yr(-1). IM increased the relative abundances of Actinobacteria and Crenarchaeota but decreased that of Acidobacteria. N addition increased the relative abundances of Acidobacteria, Crenarchaeota, and Actinobacteria but decreased that of Proteobacteria. Soil bacterial diversity was significantly related to soil pH, C/N ratio, and nitrogen and available phosphorus content. Management practices exerted a greater influence over regulation of the soil MBC and microbial diversity compared to that of N deposition in Moso bamboo plantations.

  4. Nitrogen deposition and management practices increase soil microbial biomass carbon but decrease diversity in Moso bamboo plantations

    Science.gov (United States)

    Li, Quan; Song, Xinzhang; Gu, Honghao; Gao, Fei

    2016-06-01

    Because microbial communities play a key role in carbon (C) and nitrogen (N) cycling, changes in the soil microbial community may directly affect ecosystem functioning. However, the effects of N deposition and management practices on soil microbes are still poorly understood. We studied the effects of these two factors on soil microbial biomass carbon (MBC) and community composition in Moso bamboo plantations using high-throughput sequencing of the 16S rRNA gene. Plantations under conventional (CM) or intensive management (IM) were subjected to one of four N treatments for 30 months. IM and N addition, both separately and in combination, significantly increased soil MBC while decreasing bacterial diversity. However, increases in soil MBC were inhibited when N addition exceeded 60 kg N•ha‑1•yr‑1. IM increased the relative abundances of Actinobacteria and Crenarchaeota but decreased that of Acidobacteria. N addition increased the relative abundances of Acidobacteria, Crenarchaeota, and Actinobacteria but decreased that of Proteobacteria. Soil bacterial diversity was significantly related to soil pH, C/N ratio, and nitrogen and available phosphorus content. Management practices exerted a greater influence over regulation of the soil MBC and microbial diversity compared to that of N deposition in Moso bamboo plantations.

  5. Fast skeletal muscle troponin activation increases force of mouse fast skeletal muscle and ameliorates weakness due to nebulin-deficiency.

    Directory of Open Access Journals (Sweden)

    Eun-Jeong Lee

    Full Text Available The effect of the fast skeletal muscle troponin activator, CK-2066260, on calcium-induced force development was studied in skinned fast skeletal muscle fibers from wildtype (WT and nebulin deficient (NEB KO mice. Nebulin is a sarcomeric protein that when absent (NEB KO mouse or present at low levels (nemaline myopathy (NM patients with NEB mutations causes muscle weakness. We studied the effect of fast skeletal troponin activation on WT muscle and tested whether it might be a therapeutic mechanism to increase muscle strength in nebulin deficient muscle. We measured tension-pCa relations with and without added CK-2066260. Maximal active tension in NEB KO tibialis cranialis fibers in the absence of CK-2066260 was ∼60% less than in WT fibers, consistent with earlier work. CK-2066260 shifted the tension-calcium relationship leftwards, with the largest relative increase (up to 8-fold at low to intermediate calcium levels. This was a general effect that was present in both WT and NEB KO fiber bundles. At pCa levels above ∼6.0 (i.e., calcium concentrations <1 µM, CK-2066260 increased tension of NEB KO fibers to beyond that of WT fibers. Crossbridge cycling kinetics were studied by measuring k(tr (rate constant of force redevelopment following a rapid shortening/restretch. CK-2066260 greatly increased k(tr at submaximal activation levels in both WT and NEB KO fiber bundles. We also studied the sarcomere length (SL dependence of the CK-2066260 effect (SL 2.1 µm and 2.6 µm and found that in the NEB KO fibers, CK-2066260 had a larger effect on calcium sensitivity at the long SL. We conclude that fast skeletal muscle troponin activation increases force at submaximal activation in both wildtype and NEB KO fiber bundles and, importantly, that this troponin activation is a potential therapeutic mechanism for increasing force in NM and other skeletal muscle diseases with loss of muscle strength.

  6. Cadherin-13 Deficiency Increases Dorsal Raphe 5-HT Neuron Density and Prefrontal Cortex Innervation in the Mouse Brain

    Directory of Open Access Journals (Sweden)

    Andrea Forero

    2017-09-01

    Full Text Available Background: During early prenatal stages of brain development, serotonin (5-HT-specific neurons migrate through somal translocation to form the raphe nuclei and subsequently begin to project to their target regions. The rostral cluster of cells, comprising the median and dorsal raphe (DR, innervates anterior regions of the brain, including the prefrontal cortex. Differential analysis of the mouse 5-HT system transcriptome identified enrichment of cell adhesion molecules in 5-HT neurons of the DR. One of these molecules, cadherin-13 (Cdh13 has been shown to play a role in cell migration, axon pathfinding, and synaptogenesis. This study aimed to investigate the contribution of Cdh13 to the development of the murine brain 5-HT system.Methods: For detection of Cdh13 and components of the 5-HT system at different embryonic developmental stages of the mouse brain, we employed immunofluorescence protocols and imaging techniques, including epifluorescence, confocal and structured illumination microscopy. The consequence of CDH13 loss-of-function mutations on brain 5-HT system development was explored in a mouse model of Cdh13 deficiency.Results: Our data show that in murine embryonic brain Cdh13 is strongly expressed on 5-HT specific neurons of the DR and in radial glial cells (RGCs, which are critically involved in regulation of neuronal migration. We observed that 5-HT neurons are intertwined with these RGCs, suggesting that these neurons undergo RGC-guided migration. Cdh13 is present at points of intersection between these two cell types. Compared to wildtype controls, Cdh13-deficient mice display increased cell densities in the DR at embryonic stages E13.5, E17.5, and adulthood, and higher serotonergic innervation of the prefrontal cortex at E17.5.Conclusion: Our findings provide evidence for a role of CDH13 in the development of the serotonergic system in early embryonic stages. Specifically, we indicate that Cdh13 deficiency affects the cell

  7. Can diving-induced tissue nitrogen supersaturation increase the chance of acoustically driven bubble growth in marine mammals?

    Science.gov (United States)

    Houser, D S; Howard, R; Ridgway, S

    2001-11-21

    The potential for acoustically mediated causes of stranding in cetaceans (whales and dolphins) is of increasing concern given recent stranding events associated with anthropogenic acoustic activity. We examine a potentially debilitating non-auditory mechanism called rectified diffusion. Rectified diffusion causes gas bubble growth, which in an insonified animal may produce emboli, tissue separation and high, localized pressure in nervous tissue. Using the results of a dolphin dive study and a model of rectified diffusion for low-frequency exposure, we demonstrate that the diving behavior of cetaceans prior to an intense acoustic exposure may increase the chance of rectified diffusion. Specifically, deep diving and slow ascent/descent speed contributes to increased gas-tissue saturation, a condition that amplifies the likelihood of rectified diffusion. The depth of lung collapse limits nitrogen uptake per dive and the surface interval duration influences the amount of nitrogen washout from tissues between dives. Model results suggest that low-frequency rectified diffusion models need to be advanced, that the diving behavior of marine mammals of concern needs to be investigated to identify at-risk animals, and that more intensive studies of gas dynamics within diving marine mammals should be undertaken.

  8. 不同施氮量协同打顶后同量调亏对烤烟中性致香物质含量及评吸质量的影响%Effects of different nitrogen levels and equal nitrogen deficiency after topping on neutral aroma constituents contents and smoking quality in flue-cured tobacco

    Institute of Scientific and Technical Information of China (English)

    苏菲; 史宏志; 杨军杰; 钱华; 周海燕; 穆文静; 刘国顺

    2012-01-01

    采用盆栽试验,研究了打顶前不同氮素营养水平协同打顶后同量调亏对烤烟NC 297的中性致香物质含量及评吸质量的影响.结果表明,中部叶中,高氮N1(5.250 g·盆-1)的类胡萝卜素类、苯丙氨酸类、棕色化产物类、新植二烯及中性致香物质总量均高于其他处理;上部叶中,随着施氮量增加,类胡萝卜素类、苯丙氨酸类、棕色化产物类、新植二烯及中性致香物质总量表现出先增后降的趋势,在高氮N2(4.375 g·盆-1)水平达到最大值.上部叶的茄酮含量变异较大,其含量分布为37.65~74.08 μg·g-1,且随着施氮量的增加,其含量下降显著.中部叶评吸结果以高氮N1(5.250 g·盆-1)得分最高,上部叶以高氮N2得分最高.综合来看,打顶前丰富的氮素营养协同打顶后调亏处理N2(4.375 g·盆-1),有利于烟叶优良品质的形成.%Pot experiment was conducted to study the influence of different nitrogen levels before topping and equal nitrogen deficiency after topping on neutral aroma constituents contents and smoking quality. The results showed that; the contents of aroma products degraded from carotenoid, phenylala-nine, aroma products of browning reaction, neophytadiene and the total contents of neutral aroma constituents in Nl (5.250 g · pot-1 ) were the highest in the middle leaves. While they increased first then decreased with the increasing nitrogen level in the upper leaves, and in the N2 (4. 375 g · pot -1) nitrogen level they reached their maximum value. The variation of solanene content was greater in upper leaves, and its content significantly decreased with the increasing nitrogen level ranging from 37.65 ~74.08 μg · g-1. Smoking quality was the highest in Nl (5. 250 g · pot-1) in the middle leaves, while it was the highest in N2 (4.375 g· pot-1) in upper leaves. In conclusion, abundance nitrogen level before topping and then regulated deficit nitrogen after topping treatment N2 (4. 375 g

  9. Folate deficiency increases mtDNA and D-1 mtDNA deletion in aged brain of mice lacking uracil-DNA glycosylase.

    Science.gov (United States)

    Kronenberg, Golo; Gertz, Karen; Overall, Rupert W; Harms, Christoph; Klein, Jeanette; Page, Melissa M; Stuart, Jeffrey A; Endres, Matthias

    2011-04-01

    Strong epidemiological and experimental evidence links folate deficiency and resultant hyperhomocysteinemia with cognitive decline and neurodegeneration. Here, we tested the hypothesis that uracil misincorporation contributes to mitochondrial pathology in aged brain following folate deprivation. In a 2 × 2 design, 14-month-old mice lacking uracil DNA glycosylase (Ung-/-) versus wild-type controls were subjected to a folate-deficient versus a regular diet for six weeks. Folate-deficient feeding significantly enhanced mtDNA content and overall abundance of the D-1 mtDNA deletion in brain of Ung-/-, but not of wild-type mice. Independent of folate status, the frequency of the D-1 mtDNA deletion in mtDNA was significantly increased in Ung-/- mice. The rate of mitochondrial biogenesis as assessed at six weeks of the experimental diet by mRNA expression levels of transcriptional coactivator peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α and of mitochondrial transcription factor A (Tfam) was not affected by either Ung-/- genotype or short-term folate deficiency. Similarly, citrate synthase (CS) activity in the brain did not differ across experimental groups. By contrast, independent of genotype, lactate dehydrogenase (LDH) activity was significantly reduced in folate-deficient animals. Our results suggest that impaired uracil excision repair causes an increase in mitochondrial mutagenesis in aged brain along with a compensatory increase in mtDNA content in response to low folate status. Folate deficiency may contribute to neurodegeneration via mtDNA damage.

  10. AdPLA ablation increases lipolysis and prevents obesity induced by high-fat feeding or leptin deficiency.

    Science.gov (United States)

    Jaworski, Kathy; Ahmadian, Maryam; Duncan, Robin E; Sarkadi-Nagy, Eszter; Varady, Krista A; Hellerstein, Marc K; Lee, Hui-Young; Samuel, Varman T; Shulman, Gerald I; Kim, Kee-Hong; de Val, Sarah; Kang, Chulho; Sul, Hei Sook

    2009-02-01

    A main function of white adipose tissue is to release fatty acids from stored triacylglycerol for other tissues to use as an energy source. Whereas endocrine regulation of lipolysis has been extensively studied, autocrine and paracrine regulation is not well understood. Here we describe the role of the newly identified major adipocyte phospholipase A(2), AdPLA (encoded by Pla2g16, also called HREV107), in the regulation of lipolysis and adiposity. AdPLA-null mice have a markedly higher rate of lipolysis owing to increased cyclic AMP levels arising from the marked reduction in the amount of adipose prostaglandin E(2) that binds the Galpha(i)-coupled receptor, EP3. AdPLA-null mice have markedly reduced adipose tissue mass and triglyceride content but normal adipogenesis. They also have higher energy expenditure with increased fatty acid oxidation within adipocytes. AdPLA-deficient ob/ob mice remain hyperphagic but lean, with increased energy expenditure, yet have ectopic triglyceride storage and insulin resistance. AdPLA is a major regulator of adipocyte lipolysis and is crucial for the development of obesity.

  11. Combined increases in mitochondrial cooperation and oxygen photoreduction compensate for deficiency in cyclic electron flow in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Dang, Kieu-Van; Plet, Julie; Tolleter, Dimitri; Jokel, Martina; Cuiné, Stéphan; Carrier, Patrick; Auroy, Pascaline; Richaud, Pierre; Johnson, Xenie; Alric, Jean; Allahverdiyeva, Yagut; Peltier, Gilles

    2014-07-01

    During oxygenic photosynthesis, metabolic reactions of CO2 fixation require more ATP than is supplied by the linear electron flow operating from photosystem II to photosystem I (PSI). Different mechanisms, such as cyclic electron flow (CEF) around PSI, have been proposed to participate in reequilibrating the ATP/NADPH balance. To determine the contribution of CEF to microalgal biomass productivity, here, we studied photosynthesis and growth performances of a knockout Chlamydomonas reinhardtii mutant (pgrl1) deficient in PROTON GRADIENT REGULATION LIKE1 (PGRL1)-mediated CEF. Steady state biomass productivity of the pgrl1 mutant, measured in photobioreactors operated as turbidostats, was similar to its wild-type progenitor under a wide range of illumination and CO2 concentrations. Several changes were observed in pgrl1, including higher sensitivity of photosynthesis to mitochondrial inhibitors, increased light-dependent O2 uptake, and increased amounts of flavodiiron (FLV) proteins. We conclude that a combination of mitochondrial cooperation and oxygen photoreduction downstream of PSI (Mehler reactions) supplies extra ATP for photosynthesis in the pgrl1 mutant, resulting in normal biomass productivity under steady state conditions. The lower biomass productivity observed in the pgrl1 mutant in fluctuating light is attributed to an inability of compensation mechanisms to respond to a rapid increase in ATP demand. © 2014 American Society of Plant Biologists. All rights reserved.

  12. Abcc6 deficiency causes increased infarct size and apoptosis in a mouse cardiac ischemia-reperfusion model

    NARCIS (Netherlands)

    I.N. Mungrue; P. Zhao; Y. Yao; H. Meng; C. Rau; J.V. Havel; T.G.M.F. Gorgels; A.A.B. Bergen; W.R. Maclellan; T.A. Drake; K.I. Boström; A.J. Lusis

    2011-01-01

    ABCC6 genetic deficiency underlies pseudoxanthoma elasticum (PXE) in humans, characterized by ectopic calcification, and early cardiac disease. The spectrum of PXE has been noted in Abcc6-deficient mice, including dystrophic cardiac calcification. We tested the role of Abcc6 in response to cardiac i

  13. Essential fatty acid supplemented diet increases renal excretion of prostaglandin E and water in essential fatty acid deficient rats

    DEFF Research Database (Denmark)

    Hansen, Harald S.

    1981-01-01

    Weanling male rats were fed an essential fatty acid (EFA)-deficient diet for 25 weeks and then switched to an EFA-supplemented diet for 3 weeks. Control rats received the EFA-supplemented diet for 25 weeks and then the EFA-deficient diet for 3 weeks. Throughout the last 19 weeks, the rats were...

  14. Increased oxidative stress and coenzyme Q10 deficiency in juvenile fibromyalgia: amelioration of hypercholesterolemia and fatigue by ubiquinol-10 supplementation.

    Science.gov (United States)

    Miyamae, Takako; Seki, Manabu; Naga, Tomoko; Uchino, Shinya; Asazuma, Haruki; Yoshida, Takuma; Iizuka, Yuki; Kikuchi, Masako; Imagawa, Tomoyuki; Natsumeda, Yutaka; Yokota, Shumpei; Yamamoto, Yorihiro

    2013-01-01

    Fibromyalgia (FM) is characterized by generalized pain and chronic fatigue of unknown etiology. To evaluate the role of oxidative stress in this disorder, we measured plasma levels of ubiquinone-10, ubiquinol-10, free cholesterol (FC), cholesterol esters (CE), and free fatty acids (FFA) in patients with juvenile FM (n=10) and in healthy control subjects (n=67). Levels of FC and CE were significantly increased in juvenile FM as compared with controls, suggesting the presence of hypercholesterolemia in this disease. However, plasma level of ubiquinol-10 was significantly decreased and the ratio of ubiquinone-10 to total coenzyme Q10 (%CoQ10) was significantly increased in juvenile FM relative to healthy controls, suggesting that FM is associated with coenzyme Q10 deficiency and increased oxidative stress. Moreover, plasma level of FFA was significantly higher and the content of polyunsaturated fatty acids (PUFA) in total FFA was significantly lower in FM than in controls, suggesting increased tissue oxidative damage in juvenile FM. Interestingly, the content of monoenoic acids, such as oleic and palmitoleic acids, was significantly increased in FM relative to controls, probably to compensate for the loss of PUFA. Next, we examined the effect of ubiquinol-10 supplementation (100 mg/day for 12 weeks) in FM patients. This resulted in an increase in coenzyme Q10 levels and a decrease in %CoQ10. No changes were observed in FFA levels or their composition. However, plasma levels of FC and CE significantly decreased and the ratio of FC to CE also significantly decreased, suggesting that ubiquinol-10 supplementation improved cholesterol metabolism. Ubiquinol-10 supplementation also improved chronic fatigue scores as measured by the Chalder Fatigue Scale.

  15. Increased root exudation of /sup 14/C-compounds by sorghum seedlings inoculated with nitrogen-fixing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.J. (Institute of Forest Genetics, Suweon (Republic of Korea)); Gaskins, M.H. (Florida Univ., Gainesville (USA). Dept. of Agriculture)

    1982-01-01

    Organic components leaked from Sorghum bicolor seedlings ('root exudates') were examined by recovering /sup 14/C labelled compounds from root solutions of seedlings inoculated with Azospirillum brasilense, Azotobacter vinelandii or Klebsiella pneumoniae nif-. Up to 3.5% of the total /sup 14/C recovered from shoots, roots, and nutrient solutions was found in the root solutions. Inoculation with Azospirillum and Azotobacter increased the amounts of /sup 14/C and decreased the amounts of carbohydrates in the root solutions. When sucrose was added as a carbon source for the bacteria, the increase of /sup 14/C in the solutions did not occur. Quantities of /sup 14/C found in the root solutions were proportional to amounts of mineral nitrogen supplied to the plants. Bacterial growth also was proportional to nitrogen levels. When sorghum plants were grown in soil and labelled with /sup 14/CO/sub 2/, about 15% of the total /sup 14/C recovered within 48 hours exposure was found in soil leachates.

  16. CCR2 deficiency leads to increased eosinophils, alternative macrophage activation, and type 2 cytokine expression in adipose tissue.

    Science.gov (United States)

    Bolus, W Reid; Gutierrez, Dario A; Kennedy, Arion J; Anderson-Baucum, Emily K; Hasty, Alyssa H

    2015-10-01

    Adipose tissue (AT) inflammation during obesity is mediated by immune cells and closely correlates with systemic insulin resistance. In lean AT, eosinophils are present in low but significant numbers and capable of promoting alternative macrophage activation in an IL-4/IL-13-dependent manner. In WT mice, obesity causes the proportion of AT eosinophils to decline, concomitant with inflammation and classical activation of AT macrophages. In this study, we show that CCR2 deficiency leads to increased eosinophil accumulation in AT. Furthermore, in contrast to WT mice, the increase in eosinophils in CCR2(-/-) AT is sustained and even amplified during obesity. Interestingly, a significant portion of eosinophils is found in CLSs in AT of obese CCR2(-/-) mice, which is the first time eosinophils have been shown to localize to these inflammatory hot spots. CCR2(-/-) bone marrow precursors displayed increased expression of various key eosinophil genes during in vitro differentiation to eosinophils, suggesting a potentially altered eosinophil phenotype in the absence of CCR2. In addition, the proportion of eosinophils in AT positively correlated with local expression of Il5, a potent eosinophil stimulator. The increase in eosinophils in CCR2(-/-) mice was detected in all white fat pads analyzed and in the peritoneal cavity but not in bone marrow, blood, spleen, or liver. In AT of CCR2(-/-) mice, an increased eosinophil number positively correlated with M2-like macrophages, expression of the Treg marker Foxp3, and type 2 cytokines, Il4, Il5, and Il13. This is the first study to link CCR2 function with regulation of AT eosinophil accumulation.

  17. Increased strontium uptake in trabecular bone of ovariectomized calcium-deficient rats treated with strontium ranelate or strontium chloride.

    Science.gov (United States)

    Pemmer, Bernhard; Hofstaetter, Jochen G; Meirer, Florian; Smolek, Stephan; Wobrauschek, Peter; Simon, Rolf; Fuchs, Robyn K; Allen, Matthew R; Condon, Keith W; Reinwald, Susan; Phipps, Roger J; Burr, David B; Paschalis, Eleftherios P; Klaushofer, Klaus; Streli, Christina; Roschger, Paul

    2011-11-01

    Based on clinical trials showing the efficacy to reduce vertebral and non-vertebral fractures, strontium ranelate (SrR) has been approved in several countries for the treatment of postmenopausal osteoporosis. Hence, it is of special clinical interest to elucidate how the Sr uptake is influenced by dietary Ca deficiency as well as by the formula of Sr administration, SrR versus strontium chloride (SrCl(2)). Three-month-old ovariectomized rats were treated for 90 days with doses of 25 mg kg(-1) d(-1) and 150 mg kg(-1) d(-1) of SrR or SrCl(2) at low (0.1% Ca) or normal (1.19% Ca) Ca diet. Vertebral bone tissue was analysed by confocal synchrotron-radiation-induced micro X-ray fluorescence and by backscattered electron imaging. Principal component analysis and k-means clustering of the acquired elemental maps of Ca and Sr revealed that the newly formed bone exhibited the highest Sr fractions and that low Ca diet increased the Sr uptake by a factor of three to four. Furthermore, Sr uptake in bone of the SrCl(2)-treated animals was generally lower compared with SrR. The study clearly shows that inadequate nutritional calcium intake significantly increases uptake of Sr in serum as well as in trabecular bone matrix. This indicates that nutritional calcium intake as well as serum Ca levels are important regulators of any Sr treatment.

  18. AdPLA ablation increases lipolysis and prevents obesity induced by high fat feeding or leptin deficiency

    Science.gov (United States)

    Jaworski, Kathy; Ahmadian, Maryam; Duncan, Robin E.; Sarkadi-Nagy, Eszter; Varady, Krista A.; Hellerstein, Marc K.; Lee, Hui-Young; Samuel, Varman T.; Shulman, Gerald I.; Kim, Kee-Hong; de Val, Sarah; Kang, Chulho; Sul, Hei Sook

    2010-01-01

    A main function of white adipose tissue is to release fatty acids from triacylglycerol for other tissues to use as an energy source. While endocrine regulation of lipolysis has been extensively studied, autocrine/paracrine regulation is not well understood. Here, we describe the role of AdPLA, the newly identified major adipocyte phospholipase A2, in the regulation of lipolysis and adiposity. AdPLA null mice have a markedly higher rate of lipolysis, due to increased cAMP levels arising from the marked reduction in adipose PGE2 that binds the Gαi-coupled receptor, EP3. AdPLA null mice have drastically reduced adipose tissue mass and triglyceride content, with normal adipogenesis. They also have higher energy expenditure with higher fatty acid oxidation within adipocytes. AdPLA deficient ob/ob mice remain hyperphagic but lean, with increased energy expenditure, yet have ectopic triglyceride storage and insulin resistance. AdPLA is a major regulator of adipocyte lipolysis and critical for the development of obesity. PMID:19136964

  19. Vertical modeling of the nitrogen cycle in the eastern tropical South Pacific oxygen deficient zone using high-resolution concentration and isotope measurements

    Science.gov (United States)

    Peters, Brian D.; Babbin, Andrew R.; Lettmann, Karsten A.; Mordy, Calvin W.; Ulloa, Osvaldo; Ward, Bess B.; Casciotti, Karen L.

    2016-11-01

    Marine oxygen deficient zones (ODZs) have long been identified as sites of fixed nitrogen (N) loss. However, the mechanisms and rates of N loss have been debated, and traditional methods for measuring these rates are labor-intensive and may miss hot spots in spatially and temporally variable environments. Here we estimate rates of heterotrophic nitrate reduction, heterotrophic nitrite reduction (denitrification), nitrite oxidation, and anaerobic ammonium oxidation (anammox) at a coastal site in the eastern tropical South Pacific (ETSP) ODZ based on high-resolution concentration and natural abundance stable isotope measurements of nitrate (NO3-) and nitrite (NO2-). These measurements were used to estimate process rates using a two-step inverse modeling approach. The modeled rates were sensitive to assumed isotope effects for NO3- reduction and NO2- oxidation. Nevertheless, we addressed two questions surrounding the fates of NO2- in the ODZ: (1) Is NO2- being primarily reduced to N2 or oxidized to NO3- in the ODZ? and (2) what are the contributions of anammox and denitrification to NO2- removal? Depth-integrated rates from the model suggest that 72-88% of the NO2- produced in the ODZ was oxidized back to NO3-, while 12-28% of NO2- was reduced to N2. Furthermore, our model suggested that 36-74% of NO2- loss was due to anammox, with the remainder due to denitrification. These model results generally agreed with previously measured rates, though with a large range of uncertainty, and they provide a long-term integrated view that compliments incubation experiments to obtain a broader picture of N cycling in ODZs.

  20. Transformation of the Nitrogen Cycle. Recent Trends, Questions, and Potential Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Galloway, J.N. [Environmental Sciences Department, University of Virginia, Charlottesville, VA 22904 (United States); Townsend, A.R. [Institute of Arctic and Alpine Research and Department of Ecology and Evolutionary Biology, Campus Box 450, University of Colorado, Boulder, CO 80309 (United States); Erisman, J.W. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands); Bekunda, M. [Faculty of Agriculture, Makerere University, Post Office Box 7062, Kampala (Uganda); Cai, Z. [Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Freney, J.R. [Commonwealth Scientific and Industrial Research Organisation Plant Industry, GPO Box 1600, Canberra, (Australia); Martinelli, L.A. [Centro de Energia Nuclear na Agricultura-Universidade de Sao Paulo, Avenida Centenario, 303, Piracicaba-SP (Brazil); Seitzinger, S.P. [Rutgers, The State University of New Jersey, Institute of Marine and Coastal Sciences, Rutgers/National Oceanic and Atmospheric Administration Cooperative Marine Education and Research Program, New Brunswick, NJ 08901 (United States); Sutton, M. [Centre for Ecology and Hydrology, Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH26 0QB (United Kingdom)

    2008-08-15

    Humans continue to transform the global nitrogen cycle at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land to cause a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste.

  1. Hibiscus sabdariffa increases hydroxocobalamin oral bioavailability and clinical efficacy in vitamin B12 deficiency with neurological symptoms.

    Science.gov (United States)

    Souirti, Zouhayr; Loukili, Mouna; Soudy, Imar D; Rtibi, Kaies; Özel, Aslihan; Limas-Nzouzi, Nicolas; El Ouezzani, Seloua; Eto, Bruno

    2016-12-01

    The aim of the study was to evaluate the bioavailability and clinical benefits of oral new formulation (HB12 ) of hydroxocobalamin (Hdrx) with Hibiscus sabdariffa (HS). First, in an observational study, a cohort of 30 vitamin B12 -deficient patients (vit B12 vitamin B12 level increased from 55.1 ± 36.9 to 1330 ± 335.5 pg/mL at day 10 and 431.0 ± 24.27 pg/mL at day 90, without overt adverse effects. In mice ileum, (i) intestinal bioavailability of Hdrx increased in dose-dependent manner with HB12 . The apparent permeability of Hdrx was Papp = 34.9 ± 4.6 × 10(-6) cm/s in the presence of 3 mg/mL (HB12 B) compared to the control Papp = 6.2 ± 0.7 × 10(-6) cm/s. (ii) Total transepithelial electrical conductance (Gt ) increased in dose-dependent manner with HB12 , Gt = 161.5 ± 10.8 mS/cm² with HB12 B (Hdrx 1 mg + HS 3 mg) compared to the control Hdrx, Gt = 28.7 ± 4.0 mS/cm². In conclusion, the clinical study suggests that injections are not required when Hdrx is given orally. Intestinal bioavailability of Hdrx increased in vitro when it was used concomitantly with HS. © 2016 Société Française de Pharmacologie et de Thérapeutique.

  2. Overexpression of a NAC transcription factor delays leaf senescence and increases grain nitrogen concentration in wheat.

    Science.gov (United States)

    Zhao, D; Derkx, A P; Liu, D-C; Buchner, P; Hawkesford, M J

    2015-07-01

    Increasing the duration of leaf photosynthesis during grain filling using slow-senescing functional stay-green phenotypes is a possible route for increasing grain yields in wheat (Triticum aestivum L.). However, delayed senescence may negatively affect nutrient remobilisation and hence reduce grain protein concentrations and grain quality. A novel NAC1-type transcription factor (hereafter TaNAC-S) was identified in wheat, with gene expression located primarily in leaf/sheath tissues, which decreased during post-anthesis leaf senescence. Expression of TaNAC-S in the second leaf correlated with delayed senescence in two doubled-haploid lines of an Avalon × Cadenza population (lines 112 and 181), which were distinct for leaf senescence. Transgenic wheat plants overexpressing TaNAC-S resulted in delayed leaf senescence (stay-green phenotype). Grain yield, aboveground biomass, harvest index and total grain N content were unaffected, but NAC over-expressing lines had higher grain N concentrations at similar grain yields compared to non-transgenic controls. These results indicate that TaNAC-S is a negative regulator of leaf senescence, and that delayed leaf senescence may lead not only to increased grain yields but also to increased grain protein concentrations.

  3. Soil responses to management, increased precipitation, and added nitrogen in ponderosa pine forests.

    Science.gov (United States)

    Hungate, Bruce A; Hart, Stephen C; Selmants, Paul C; Boyle, Sarah I; Gehring, Catherine A

    2007-07-01

    Forest management, climatic change, and atmospheric N deposition can affect soil biogeochemistry, but their combined effects are not well understood. We examined the effects of water and N amendments and forest thinning and burning on soil N pools and fluxes in ponderosa pine forests near Flagstaff, Arizona (USA). Using a 15N-depleted fertilizer, we also documented the distribution of added N into soil N pools. Because thinning and burning can increase soil water content and N availability, we hypothesized that these changes would alleviate water and N limitation of soil processes, causing smaller responses to added N and water in the restored stand. We found little support for this hypothesis. Responses of fine root biomass, potential net N mineralization, and the soil microbial N to water and N amendments were mostly unaffected by stand management. Most of the soil processes we examined were limited by N and water, and the increased N and soil water availability caused by forest restoration was insufficient to alleviate these limitations. For example, N addition caused a larger increase in potential net nitrification in the restored stand, and at a given level of soil N availability, N addition had a larger effect on soil microbial N in the restored stand. Possibly, forest restoration increased the availability of some other limiting resource, amplifying responses to added N and water. Tracer N recoveries in roots and in the forest floor were lower in the restored stand. Natural abundance delta15N of labile soil N pools were higher in the restored stand, consistent with a more open N cycle. We conclude that thinning and burning open up the N cycle, at least in the short-term, and that these changes are amplified by enhanced precipitation and N additions. Our results suggest that thinning and burning in ponderosa pine forests will not increase their resistance to changes in soil N dynamics resulting from increased atmospheric N deposition or increased

  4. Climatic warming increases winter wheat yield but reduces grain nitrogen concentration in east China.

    Directory of Open Access Journals (Sweden)

    Yunlu Tian

    Full Text Available Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05, respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05 higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat.

  5. Nitrogen-deficient microalgae are rich in cell-surface mannose: potential implications for prey biorecognition by phagotrophic protozoa Microalgas com deficiência de nitrogênio são enriquecidas com manose na superfície celular: potenciais implicações para reconhecimento de presas por protozoários fagotróficos

    Directory of Open Access Journals (Sweden)

    Claire M. Martel

    2009-03-01

    Full Text Available Flow cytometry was used to quantify the abundance of mannose-linked glycoconjugates on microalgae precultured using low- or high-nitrate media. Nitrogen-deficient microalgae were richer in cell-surface mannose than nitrogen-sufficient. Findings are discussed in view of recent research which reveals mannose-specific 'feeding receptors' assist prey biorecognition by phagotrophic protozoa that ingest microalgae.Citometria de fluxo foi usada para quantificar a abundância de glicoconjugados com manose em precultivos de microalgas usando meios com baixo e alto teor de nitrato. Microalgas com deficiências de nitrogênio tinham mais manose na superfície celular do que as com nitrogênio suficiente. Resultados são discutidos com base nas pesquisas recentes que revelam receptores específicos para manose que auxiliam no reconhecimento da presa por protozoários fagotróficos que ingerem microalgas.

  6. Prolonged renal allograft survival by donor interleukin-6 deficiency: association with decreased alloantibodies and increased intragraft T regulatory cells.

    Science.gov (United States)

    Wang, Hao; Guan, Qiunong; Lan, Zhu; Li, Shuyuan; Ge, Wei; Chen, Huifang; Nguan, Christopher Y C; Du, Caigan

    2012-01-15

    Both humoral and cellular immune responses are involved in renal allograft rejection. Interleukin (IL)-6 is a regulatory cytokine for both B and Foxp3 (forkhead box P3)-expressing regulatory T (Treg) cells. This study was designed to investigate the impact of donor IL-6 production on renal allograft survival. Donor kidneys from IL-6 knockout (KO) vs. wild-type (WT) C57BL/6 mice (H-2(b)) were orthotopically transplanted to nephrotomized BALB/c mice (H-2(d)). Alloantibodies and Treg cells were examined by fluorescence-activated cell sorting analysis. Graft survival was determined by the time to graft failure. Here, we showed that a deficiency in IL-6 expression in donor kidneys significantly prolonged renal allograft survival compared with WT controls. IL-6 protein was upregulated in renal tubules and endothelium of renal allografts following rejection, which correlated with an increase in serum IL-6 compared with that in those receiving KO grafts or naive controls. The absence of graft-producing IL-6 or lower levels of serum IL-6 in the recipients receiving IL-6 KO allografts was associated with decreased circulating anti-graft alloantibodies and increased the percentage of intragraft CD4(+)CD25(+)Foxp3(+) Treg cells compared with those with WT allografts. In conclusion, the lack of graft-producing IL-6 significantly prolongs renal allograft survival, which is associated with reduced alloantibody production and/or increased intragraft Treg cell population, implying that targeting donor IL-6 may effectively prevent both humoral and cellular rejection of kidney transplants.

  7. Endogenous IL-33 Deficiency Exacerbates Liver Injury and Increases Hepatic Influx of Neutrophils in Acute Murine Viral Hepatitis

    Science.gov (United States)

    Carrière, Virginie; Arshad, Muhammad Imran; Le Seyec, Jacques; Lefevre, Benjamin; Farooq, Muhammad; Jan, Aurélien; Manuel, Christelle; Touami-Bernard, Laurence; Lucas-Clerc, Catherine; Genet, Valentine; Gascan, Hugues; Girard, Jean-Philippe; Chalmel, Frédéric; Lamontagne, Lucie; Piquet-Pellorce, Claire

    2017-01-01

    The alarmin IL-33 has been described to be upregulated in human and murine viral hepatitis. However, the role of endogenous IL-33 in viral hepatitis remains obscure. We aimed to decipher its function by infecting IL-33-deficient mice (IL-33 KO) and their wild-type (WT) littermates with pathogenic mouse hepatitis virus (L2-MHV3). The IL-33 KO mice were more sensitive to L2-MHV3 infection exhibiting higher levels of AST/ALT, higher tissue damage, significant weight loss, and earlier death. An increased depletion of B and T lymphocytes, NKT cells, dendritic cells, and macrophages was observed 48 h postinfection (PI) in IL-33 KO mice than that in WT mice. In contrast, a massive influx of neutrophils was observed in IL-33 KO mice at 48 h PI. A transcriptomic study of inflammatory and cell-signaling genes revealed the overexpression of IL-6, TNFα, and several chemokines involved in recruitment/activation of neutrophils (CXCL2, CXCL5, CCL2, and CCL6) at 72 h PI in IL-33 KO mice. However, the IFNγ was strongly induced in WT mice with less profound expression in IL-33 KO mice demonstrating that endogenous IL-33 regulated IFNγ expression during L2-MHV3 hepatitis. In conclusion, we demonstrated that endogenous IL-33 had multifaceted immunoregulatory effect during viral hepatitis via induction of IFNγ, survival effect on immune cells, and infiltration of neutrophils in the liver. PMID:28607531

  8. Endogenous IL-33 Deficiency Exacerbates Liver Injury and Increases Hepatic Influx of Neutrophils in Acute Murine Viral Hepatitis

    Directory of Open Access Journals (Sweden)

    Virginie Carrière

    2017-01-01

    Full Text Available The alarmin IL-33 has been described to be upregulated in human and murine viral hepatitis. However, the role of endogenous IL-33 in viral hepatitis remains obscure. We aimed to decipher its function by infecting IL-33-deficient mice (IL-33 KO and their wild-type (WT littermates with pathogenic mouse hepatitis virus (L2-MHV3. The IL-33 KO mice were more sensitive to L2-MHV3 infection exhibiting higher levels of AST/ALT, higher tissue damage, significant weight loss, and earlier death. An increased depletion of B and T lymphocytes, NKT cells, dendritic cells, and macrophages was observed 48 h postinfection (PI in IL-33 KO mice than that in WT mice. In contrast, a massive influx of neutrophils was observed in IL-33 KO mice at 48 h PI. A transcriptomic study of inflammatory and cell-signaling genes revealed the overexpression of IL-6, TNFα, and several chemokines involved in recruitment/activation of neutrophils (CXCL2, CXCL5, CCL2, and CCL6 at 72 h PI in IL-33 KO mice. However, the IFNγ was strongly induced in WT mice with less profound expression in IL-33 KO mice demonstrating that endogenous IL-33 regulated IFNγ expression during L2-MHV3 hepatitis. In conclusion, we demonstrated that endogenous IL-33 had multifaceted immunoregulatory effect during viral hepatitis via induction of IFNγ, survival effect on immune cells, and infiltration of neutrophils in the liver.

  9. Physical properties of a Red-Yellow Latosol and productivity of a signalgrass pasture fertilized with increasing nitrogen doses

    Directory of Open Access Journals (Sweden)

    Igor Alexandre de Souza

    2013-12-01

    Full Text Available The physical properties and fertility of the soil are important factors in the formation and establishment of pasture. Changes in physical properties affect the movement of water, air, nutrients and roots, which, in turn, affect the productivity and longevity of pastures. The objective of this study was to evaluate the physical properties of the soil and the dry matter yield of a pasture with signalgrass cv. Basilisk (Brachiaria decumbens cv. Basilisk, fertilized with increasing nitrogen doses (N, on a dystrophic Red-Yellow Latosol. The experiment was conducted on the Fazenda Rio Manso of the Universidade Federal dos Vales do Jequitinhonha e Mucuri, in Couto de Magalhães de Minas, State of Minas Gerais, Brazil. To evaluate the annual forage yield, a split plot scheme in a randomized block design with four replications was used, with N doses (0, 50, 100, 150, and 200 kg/ha/year in the plots and growing seasons (first and second in the subplots. For soil evaluation, a split plot scheme was used with N doses (0, 25, 50, 75 and 100 kg/ha/cut in the plots and three sampling times (prior to the experiment, at the end of the first growing season and at the end of the second growing season in the subplots in a randomized block design with four replications. This analysis was performed separately at two soil depths (0-3 and 10-13 cm. Forage samples were analyzed for the annual dry matter yield (DMY, and soil samples were analyzed for pre-consolidation pressure (σp, initial soil bulk density (Bd, total pore volume (TPV and void index (Vd. Higher nitrogen doses increased the dry matter yield of signalgrass pasture and the pre-consolidation pressure of the soil. The total pore volume and void index decreased, and the initial soil bulk density increased, though without promoting soil compaction.

  10. Increased constitutive nitric oxide production by whole body periodic acceleration ameliorates alterations in cardiomyocytes associated with utrophin/dystrophin deficiency.

    Science.gov (United States)

    Lopez, Jose R; Kolster, Juan; Zhang, Rui; Adams, Jose

    2017-07-01

    Duchenne Muscular Dystrophy (DMD) cardiomyopathy is a progressive lethal disease caused by the lack of the dystrophin protein in the heart. The most widely used animal model of DMD is the dystrophin-deficient mdx mouse; however, these mice exhibit a mild dystrophic phenotype with heart failure only late in life. In contrast, mice deficient for both dystrophin and utrophin (mdx/utrn(-/-), or dKO) can be used to model severe DMD cardiomyopathy where pathophysiological indicators of heart failure are detectable by 8-10weeks of age. Nitric oxide (NO) is an important signaling molecule involved in vital functions of regulating rhythm, contractility, and microcirculation of the heart, and constitutive NO production affects the function of proteins involved in excitation-contraction coupling. In this study, we explored the efficacy of enhancing NO production as a therapeutic strategy for treating DMD cardiomyopathy using the dKO mouse model of DMD. Specifically, NO production was induced via whole body periodic acceleration (pGz), a novel non-pharmacologic intervention which enhances NO synthase (NOS) activity through sinusoidal motion of the body in a headward-footward direction, introducing pulsatile shear stress to the vascular endothelium and cardiomyocyte plasma membrane. Male dKO mice were randomized at 8weeks of age to receive daily pGz (480cpm, Gz±3.0m/s(2), 1h/d) for 4weeks or no treatment, and a separate age-matched group of WT animals (pGz-treated and untreated) served as non-diseased controls. At the conclusion of the protocol, cardiomyocytes from untreated dKO animals had, respectively, 4.3-fold and 3.5-fold higher diastolic resting concentration of Ca(2+) ([Ca(2+)]d) and Na(+) ([Na(+)]d) compared to WT, while pGz treatment significantly reduced these levels. For dKO cardiomyocytes, pGz treatment also improved the depressed contractile function, decreased oxidative stress, blunted the elevation in calpain activity, and mitigated the abnormal increase in [Ca

  11. Influência de formas de nitrogênio e do ph na correção da deficiência de ferro no girassol Influence of nitrogen forms and ph in the correction of iron deficiency in sunflower

    Directory of Open Access Journals (Sweden)

    Renato Mello Prado

    2011-01-01

    deficiency. The experiment was performed with the culture of sunflower (Sungro 393 in slow growth of the Laboratory of Plant Nutrition, University of Cordoba, Spain. Initially the plants were cultivated for 11 days in pots containing 0.5 L of nutrient solution (40 mM Fe. Then the plants were subjected to stress, renewing with the same nutrient solution, decreasing the concentration of 5 mM Fe and adding 15 mM NaHCO3 and CaCO3 0.5 g L-1. In plants with iron deficiency, was submitted to five treatments, consisting of (a control without Fe, maintaining the same nutrient solution before (b nitrate nutrient solution with 2 mM Ca (NO32, (c nutrient solution with ammonium 2 mM (NH42SO4 (d nutrient solution with dilute HCl, pH 3.5 (e spraying the leaves with 0.5 mM H2SO4 and with five replications. We conducted assessment of indirect measurement of chlorophyll and the measured pH value of the nutrient solution, from 0, 2, 5 and 7 days after treatment application and at last assessment was conducted on the foliar analysis by determining the Fe and total plant dry matter. The use of ammonium nutrient solution decreased the pH of nutrient solution and increased the leaf content of iron and the SPAD value of leaves, eliminating the visual symptoms of iron deficiency in sunflower. The use of ammonium in nutrient solution for seven days, was more effective in correcting iron deficiency in sunflower plants, compared with nitrate and with dilute acid at pH 3.5 and acidic leaf.

  12. Enhanced thermal stability and mechanical properties of nitrogen deficient titanium aluminum nitride (Ti0.54Al0.46Ny) thin films by tuning the applied negative bias voltage

    Science.gov (United States)

    Calamba, K. M.; Schramm, I. C.; Johansson Jõesaar, M. P.; Ghanbaja, J.; Pierson, J. F.; Mücklich, F.; Odén, M.

    2017-08-01

    Aspects on the phase stability and mechanical properties of nitrogen deficient (Ti0.54Al0.46)Ny alloys were investigated. Solid solution alloys of (Ti,Al)N were grown by cathodic arc deposition. The kinetic energy of the impinging ions was altered by varying the substrate bias voltage from -30 V to -80 V. Films deposited with a high bias value of -80 V showed larger lattice parameter, finer columnar structure, and higher compressive residual stress resulting in higher hardness than films biased at -30 V when comparing their as-deposited states. At elevated temperatures, the presence of nitrogen vacancies and point defects (anti-sites and self-interstitials generated by the ion-bombardment during coating deposition) in (Ti0.54Al0.46)N0.87 influence the driving force for phase separation. Highly biased nitrogen deficient films have point defects with higher stability during annealing, which cause a delay of the release of the stored lattice strain energy and then accelerates the decomposition tendencies to thermodynamically stable c-TiN and w-AlN. Low biased nitrogen deficient films have retarded phase transformation to w-AlN, which results in the prolongment of age hardening effect up to 1100 °C, i.e., the highest reported temperature for Ti-Al-N material system. Our study points out the role of vacancies and point defects in engineering thin films with enhanced thermal stability and mechanical properties for high temperature hard coating applications.

  13. Increasing the active surface of titanium islands on graphene by nitrogen sputtering

    CERN Document Server

    Mashoff, T; Miseikis, V; Coletti, C; Piazza, V; Beltram, F; Heun, S

    2014-01-01

    Titanium-island formation on graphene as a function of defect density is investigated. When depositing titanium on pristine graphene, titanium atoms cluster and form islands with an average diameter of about 10nm and an average height of a few atomic layers. We show that if defects are introduced in the graphene by ion bombardment, the mobility of the deposited titanium atoms is reduced and the average diameter of the islands decreases to 5nm with monoatomic height. This results in an optimized coverage for hydrogen storage applications since the actual titanium surface available per unit graphene area is significantly increased.

  14. Compensation for dystrophin-deficiency: ADAM12 overexpression in skeletal muscle results in increased alpha 7 integrin, utrophin and associated glycoproteins

    DEFF Research Database (Denmark)

    Moghadaszadeh, Behzad; Albrechtsen, Reidar; Guo, Ling T;

    2003-01-01

    , and suggested that significant changes in mdx/ADAM12 muscle might occur post-transcriptionally. Indeed, by immunostaining and immunoblotting we found an approximately 2-fold increase in expression, and distinct extrasynaptic localization, of alpha 7B integrin and utrophin, the functional homolog of dystrophin....... The expression of the dystrophin-associated glycoproteins was also increased. In conclusion, these results demonstrate a novel way to alleviate dystrophin deficiency in mice, and may stimulate the development of new approaches to compensate for dystrophin deficiency in animals and humans....

  15. Optimum Leaf Removal Increases Nitrogen Accumulation in Kernels of Maize Grown at High Density

    Science.gov (United States)

    Liu, Tiening; Huang, Rundong; Cai, Tie; Han, Qingfang; Dong, Shuting

    2017-01-01

    Increasing plant density is one of the main approaches of achieving higher yields for modern maize crop. However, there exists leaf redundancy for high-density maize, and leaves of the upper canopy shade more competent leaves at the middle strata. In a two-year field experiments, Jinhai5, a semi-compact corn cultivar, was grown at a density of 105,000 plants ha−1 grown until 3 days after silking (3DAS), when plants were subjected to removal of the uppermost two leaves (S2), four leaves (S4) or six leaves (S6), with no leaf removal as control (S0). We evaluated the effects of leaf removal on N remobilization, photosynthetic capacity of the remaining leaves for N uptake, and N accumulation in kernels. Our present results concluded that, under high plant density, excising the uppermost two leaves promoted N remobilization from vegetative organs to kernels and enhanced photosynthetic capacity for N uptake, leading to an increased N accumulation in kernels (19.6% higher than control). However, four or six uppermost leaves removal reduced N remobilization from stem and photosynthesis for poor N uptake, resulting in 37.5 and 50.2% significantly reduced N accumulation in kernels, respectively. PMID:28084467

  16. Response of Sphagnum mosses to increased CO{sub 2} concentration and nitrogen deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jauhiainen, J.

    1998-12-31

    The main objective of this work was to study the effects of different CO{sub 2} concentration and N deposition rates on Sphagna adapted to grow along a nutrient availability gradient (i.e. ombrotrophy-mesotrophy-eutrophy). The study investigated: (i) the effects of various longterm CO{sub 2} concentrations on the rate of net photosynthesis in Sphagna, (ii) the effects of the CO{sub 2} and N treatments on the moss density, shoot dry masses, length increment and dry mass production in Sphagna, (iii) the concentrations of the major nutrients in Sphagna after prolonged exposure to the CO{sub 2} and N treatments, and (iv) species dependent differences in potential NH{sub 4}{sup +} and NO{sub 3}{sup -} uptake rates. The internal nutrient concentration of the capitulum and the production of biomass were effected less by the elevated CO{sub 2} concentrations because the availability of N was a controlling factor. In addition responses to the N treatments were related to ecological differences between the Sphagna species. Species with a high tolerance of N availability were able to acclimatise to the increased N deposition rates. The data suggests a high nutrient status is less significant than the adaptation of the Sphagna to their ecological niche (e.g. low tolerance of meso-eutrophic S. warnstorfii to high N deposition rate). At the highest N deposition rate the ombrotrophic S. fuscum had the highest increase in tissue N concentration among the Sphagna studied. S. fuscum almost died at the highest N deposition rate because of the damaging effects of N to the plant`s metabolism. Ombrotrophic hummock species such as S. fuscum, were also found to have the highest potential N uptake rate (on density of dry mass basis) compared to lawn species. The rate of net photosynthesis was initially increased with elevated CO{sub 2} concentrations, but photosynthesis was down regulated with prolonged exposure to CO{sub 2}. The water use efficiency in Sphagna appeared not to be coupled

  17. Mice deficient for the extracellular matrix glycoprotein tenascin-r show physiological and structural hallmarks of increased hippocampal excitability, but no increased susceptibility to seizures in the pilocarpine model of epilepsy.

    Science.gov (United States)

    Brenneke, F; Bukalo, O; Dityatev, A; Lie, A A

    2004-01-01

    Recognition molecules provide important cues for neuronal survival, axonal fasciculation, axonal pathfinding, synaptogenesis, synaptic plasticity, and regeneration. Our previous studies revealed a link between perisomatic inhibition and the extracellular matrix glycoprotein tenascin-R (TN-R). Therefore, we here studied neuronal excitability and epileptic susceptibility in mice constitutively deficient in TN-R. In vitro analysis of populational spikes in hippocampal slices of TN-R-deficient mice revealed a significant increase in multiple spikes in the CA1 region, as compared with wild-type mice. This difference between genotypes was only partially reduced after blockade of GABA(A) receptors with picrotoxin, indicating a deficit in GABAergic inhibition and an increase in intrinsic excitability of CA1 pyramidal cells in TN-R-deficient mice. Using a battery of immunohistochemical markers and histological stainings, we were able to identify two abnormalities in the hippocampus of TN-R-deficient mice possibly related to increased excitability: the high number of glial fibrillary acidic protein-positive astrocytes and low number of calretinin-positive interneurons in the CA1 and CA3 regions. In order to test whether the revealed abnormalities give rise to increased susceptibility to seizures in TN-R-deficient mice, we used the pilocarpine model of epilepsy. No genotype-specific differences were found with regard to the time-course of pilocarpine-induced and spontaneous seizures, neuronal cell loss, aberrant sprouting and distribution of synaptic and inhibitory interneuron markers. However, pilocarpine-induced astrogliosis and reduction in calretinin-positive interneurons were less pronounced in TN-R mutants, thereby resulting in an occlusion of effects induced by TN-R deficiency and pilocarpine. Thus, TN-R-deficient mutants show several electrophysiological and morphological hallmarks of increased neuronal excitability, which, however, do not give rise to more

  18. Deficiency of Nuclear Receptor Nur77 Aggravates Mouse Experimental Colitis by Increased NFκB Activity in Macrophages.

    Directory of Open Access Journals (Sweden)

    Anouk A J Hamers

    Full Text Available Nuclear receptor Nur77, also referred to as NR4A1 or TR3, plays an important role in innate and adaptive immunity. Nur77 is crucial in regulating the T helper 1/regulatory T-cell balance, is expressed in macrophages and drives M2 macrophage polarization. In this study we aimed to define the function of Nur77 in inflammatory bowel disease. In wild-type and Nur77-/- mice, colitis development was studied in dextran sodium sulphate (DSS- and 2,4,6-trinitrobenzene sulfonic acid (TNBS-induced models. To understand the underlying mechanism, Nur77 was overexpressed in macrophages and gut epithelial cells. Nur77 protein is expressed in colon tissues from Crohn's disease and Ulcerative colitis patients and colons from colitic mice in inflammatory cells and epithelium. In both mouse colitis models inflammation was increased in Nur77-/- mice. A higher neutrophil influx and enhanced IL-6, MCP-1 and KC production was observed in Nur77-deficient colons after DSS-treatment. TNBS-induced influx of T-cells and inflammatory monocytes into the colon was higher in Nur77-/- mice, along with increased expression of MCP-1, TNFα and IL-6, and decreased Foxp3 RNA expression, compared to wild-type mice. Overexpression of Nur77 in lipopolysaccharide activated RAW macrophages resulted in up-regulated IL-10 and downregulated TNFα, MIF-1 and MCP-1 mRNA expression through NFκB repression. Nur77 also strongly decreased expression of MCP-1, CXCL1, IL-8, MIP-1α and TNFα in gut epithelial Caco-2 cells. Nur77 overexpression suppresses the inflammatory status of both macrophages and gut epithelial cells and together with the in vivo mouse data this supports that Nur77 has a protective function in experimental colitis. These findings may have implications for development of novel targeted treatment strategies regarding inflammatory bowel disease and other inflammatory diseases.

  19. Carrageenan-Induced Colonic Inflammation Is Reduced in Bcl10 Null Mice and Increased in IL-10-Deficient Mice

    Directory of Open Access Journals (Sweden)

    Sumit Bhattacharyya

    2013-01-01

    Full Text Available The common food additive carrageenan is a known activator of inflammation in mammalian tissues and stimulates both the canonical and noncanonical pathways of NF-κB activation. Exposure to low concentrations of carrageenan (10 μg/mL in the water supply has produced glucose intolerance, insulin resistance, and impaired insulin signaling in C57BL/6 mice. B-cell leukemia/lymphoma 10 (Bcl10 is a mediator of inflammatory signals from Toll-like receptor (TLR 4 in myeloid and epithelial cells. Since the TLR4 signaling pathway is activated in diabetes and by carrageenan, we addressed systemic and intestinal inflammatory responses following carrageenan exposure in Bcl10 wild type, heterozygous, and null mice. Fecal calprotectin and circulating keratinocyte chemokine (KC, nuclear RelA and RelB, phospho(Thr559-NF-κB-inducing kinase (NIK, and phospho(Ser36-IκBα in the colonic epithelial cells were significantly less (P<0.001 in the carrageenan-treated Bcl10 null mice than in controls. IL-10-deficient mice exposed to carrageenan in a germ-free environment showed an increase in activation of the canonical pathway of NF-κB (RelA activation, but without increase in RelB or phospho-Bcl10, and exogenous IL-10 inhibited only the canonical pathway of NF-κB activation in cultured colonic cells. These findings demonstrate a Bcl10 requirement for maximum development of carrageenan-induced inflammation and lack of complete suppression by IL-10 of carrageenan-induced inflammation.

  20. Nitrogen Cycling from Increased Soil Organic Carbon Contributes Both Positively and Negatively to Ecosystem Services in Wheat Agro-Ecosystems.

    Science.gov (United States)

    Palmer, Jeda; Thorburn, Peter J; Biggs, Jody S; Dominati, Estelle J; Probert, Merv E; Meier, Elizabeth A; Huth, Neil I; Dodd, Mike; Snow, Val; Larsen, Joshua R; Parton, William J

    2017-01-01

    Soil organic carbon (SOC) is an important and manageable property of soils that impacts on multiple ecosystem services through its effect on soil processes such as nitrogen (N) cycling and soil physical properties. There is considerable interest in increasing SOC concentration in agro-ecosystems worldwide. In some agro-ecosystems, increased SOC has been found to enhance the provision of ecosystem services such as the provision of food. However, increased SOC may increase the environmental footprint of some agro-ecosystems, for example by increasing nitrous oxide emissions. Given this uncertainty, progress is needed in quantifying the impact of increased SOC concentration on agro-ecosystems. Increased SOC concentration affects both N cycling and soil physical properties (i.e., water holding capacity). Thus, the aim of this study was to quantify the contribution, both positive and negative, of increased SOC concentration on ecosystem services provided by wheat agro-ecosystems. We used the Agricultural Production Systems sIMulator (APSIM) to represent the effect of increased SOC concentration on N cycling and soil physical properties, and used model outputs as proxies for multiple ecosystem services from wheat production agro-ecosystems at seven locations around the world. Under increased SOC, we found that N cycling had a larger effect on a range of ecosystem services (food provision, filtering of N, and nitrous oxide regulation) than soil physical properties. We predicted that food provision in these agro-ecosystems could be significantly increased by increased SOC concentration when N supply is limiting. Conversely, we predicted no significant benefit to food production from increasing SOC when soil N supply (from fertiliser and soil N stocks) is not limiting. The effect of increasing SOC on N cycling also led to significantly higher nitrous oxide emissions, although the relative increase was small. We also found that N losses via deep drainage were minimally

  1. Carbon, Nitrogen, and Phosphorus Increase in Soil Physical Fractions Following Vegetation Change from Grassland to Woodland

    Science.gov (United States)

    Kantola, I. B.; Boutton, T. W.; Filley, T. R.; Hallmark, C. T.

    2009-12-01

    Woody plant encroachment has been pervasive in grass-dominated ecosystems around the world during the past century due to livestock grazing, fire suppression, and/or changes in climate and atmospheric chemistry. In the Rio Grande Plains of Texas, subtropical thorn woodlands dominated by N-fixing tree legumes have largely replaced grasslands. This dramatic land cover change has increased above- and belowground primary productivity and accelerated rates of biogeochemical processes in the soil. The purpose of this study was to assess the impact of this grassland to woodland transition on C, N, and P concentrations in soil physical fractions that differ in turnover rates. Soil samples (0-10 cm) were collected in remnant grasslands and near the centers of woody plant clusters ranging in age from 15 to 90 yrs in a subtropical savanna parkland in southern Texas. Soils were fractionated by wet sieving into five size and density classes: un-sieved whole soil, free light fraction (density 250 µm), microaggregates (53-250 µm), and free silt and clay (plant-microbe and plant-plant interactions, and successional dynamics in this ecosystem.

  2. Conversion of Natural Ecosystems to Cropland Increases the Soil Net Nitrogen mineralization and Nitrification in Tibet

    Institute of Scientific and Technical Information of China (English)

    YANG Li-Lin; ZHANG Fu-Suo; MAO Ren-Zhao; JU Xiao-Tang; Cai Xiao-Bu; LI Ya-Hai

    2008-01-01

    A comparative study was conducted to determine the NH+4 and NO-3 concentrations in soil profiles and to examine the net itrogen (N) mineralization and nitrification in adjacent forest, grassland, and cropland soils on the Tibetan Plateau. Cropland soil showed significantly higher inorganic N concentrations in soil profiles compared with forest and grassland soils. NO-3-Naccounted for 70%-90% of inorganic N in cropland soil, while NH+4-N was the main form of inorganic N in forest and grassland soils. The average net N mineralization rate at 0-20 cm depth was approximately twice in cropland soil (1.48 mg kg-1 d-1) as high as in forest (0.83 mg kg-1 d-1) or grassland soil (0.72 mg kg-1 d-1). Cropland showed strong net nitrification, with the net rate almost equal to the total net N mineralization. Urea addition stimulated soil respiration, particularly in forest oil. Most urea-N, however, remained as NH+4 in forest and grassland soils, while NO-3 was the main form of inorganic N to increase n cropland soil. Higher rates of net nitrification in cropland soils suggest that land use change on the Tibetan Plateau may lead to high N losses through nitrate leaching.

  3. Increasing CO[sub 2] from glacial to present concentrations alters nitrogen and water requirements of C[sub 3] plants

    Energy Technology Data Exchange (ETDEWEB)

    Wayne, P.H.; Johnson, H.B.; Mayeux, H.S. (USDA-ARS, Temple, TX (United States))

    1994-06-01

    Nitrogen and water use efficiencies were measured for three C[sub 3] species, annual grasses Bromus tectorum (cheatgrass) and Triticum aestivum (wheat; two cultivars) and a woody perennial Prosopis glandulosa (mesquite), grown at daytime CO[sub 2] concentrations that spanned glacial to present atmospheric levels. Changes in nitrogen and water use efficiencies were used to investigate effects of increasing [CO[sub 2

  4. Zinc, iron, manganese and copper uptake requirement in response to nitrogen supply and the increased grain yield of summer maize.

    Science.gov (United States)

    Xue, Yanfang; Yue, Shanchao; Zhang, Wei; Liu, Dunyi; Cui, Zhenling; Chen, Xinping; Ye, Youliang; Zou, Chunqin

    2014-01-01

    The relationships between grain yields and whole-plant accumulation of micronutrients such as zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) in maize (Zea mays L.) were investigated by studying their reciprocal internal efficiencies (RIEs, g of micronutrient requirement in plant dry matter per Mg of grain). Field experiments were conducted from 2008 to 2011 in North China to evaluate RIEs and shoot micronutrient accumulation dynamics during different growth stages under different yield and nitrogen (N) levels. Fe, Mn and Cu RIEs (average 64.4, 18.1 and 5.3 g, respectively) were less affected by the yield and N levels. ZnRIE increased by 15% with an increased N supply but decreased from 36.3 to 18.0 g with increasing yield. The effect of cultivars on ZnRIE was similar to that of yield ranges. The substantial decrease in ZnRIE may be attributed to an increased Zn harvest index (from 41% to 60%) and decreased Zn concentrations in straw (a 56% decrease) and grain (decreased from 16.9 to 12.2 mg kg-1) rather than greater shoot Zn accumulation. Shoot Fe, Mn and Cu accumulation at maturity tended to increase but the proportions of pre-silking shoot Fe, Cu and Zn accumulation consistently decreased (from 95% to 59%, 90% to 71% and 91% to 66%, respectively). The decrease indicated the high reproductive-stage demands for Fe, Zn and Cu with the increasing yields. Optimized N supply achieved the highest yield and tended to increase grain concentrations of micronutrients compared to no or lower N supply. Excessive N supply did not result in any increases in yield or micronutrient nutrition for shoot or grain. These results indicate that optimized N management may be an economical method of improving micronutrient concentrations in maize grain with higher grain yield.

  5. Zinc, iron, manganese and copper uptake requirement in response to nitrogen supply and the increased grain yield of summer maize.

    Directory of Open Access Journals (Sweden)

    Yanfang Xue

    Full Text Available The relationships between grain yields and whole-plant accumulation of micronutrients such as zinc (Zn, iron (Fe, manganese (Mn and copper (Cu in maize (Zea mays L. were investigated by studying their reciprocal internal efficiencies (RIEs, g of micronutrient requirement in plant dry matter per Mg of grain. Field experiments were conducted from 2008 to 2011 in North China to evaluate RIEs and shoot micronutrient accumulation dynamics during different growth stages under different yield and nitrogen (N levels. Fe, Mn and Cu RIEs (average 64.4, 18.1 and 5.3 g, respectively were less affected by the yield and N levels. ZnRIE increased by 15% with an increased N supply but decreased from 36.3 to 18.0 g with increasing yield. The effect of cultivars on ZnRIE was similar to that of yield ranges. The substantial decrease in ZnRIE may be attributed to an increased Zn harvest index (from 41% to 60% and decreased Zn concentrations in straw (a 56% decrease and grain (decreased from 16.9 to 12.2 mg kg-1 rather than greater shoot Zn accumulation. Shoot Fe, Mn and Cu accumulation at maturity tended to increase but the proportions of pre-silking shoot Fe, Cu and Zn accumulation consistently decreased (from 95% to 59%, 90% to 71% and 91% to 66%, respectively. The decrease indicated the high reproductive-stage demands for Fe, Zn and Cu with the increasing yields. Optimized N supply achieved the highest yield and tended to increase grain concentrations of micronutrients compared to no or lower N supply. Excessive N supply did not result in any increases in yield or micronutrient nutrition for shoot or grain. These results indicate that optimized N management may be an economical method of improving micronutrient concentrations in maize grain with higher grain yield.

  6. [Role of heat-shock proteins of Hsp70 family in changes of narcotic activity of hyperbaric nitrogen during increasing hypoxic stimulus].

    Science.gov (United States)

    Vetosh, A N; Kostkin, V B; Alekseeva, O A; Korzhevskiĭ, D E

    2008-01-01

    The spontaneous motor activity and pose reflexes of male adult rats (Wistar) were observed in the course of high pressure nitrogen compression up to 4,1 MPa. The experiments were carried out under normoxic and hypoxic conditions. Stabile rat motor cortex oxygen tension was recording during the nitrogen compression up to 7,1 MPa under normoxic condition. Sensitivity to nitrogen high pressure to be on the increase under hypoxic conditions. In its turn, resistibility to nitrogen high pressure to be on the decrease under hypoxic conditions (oxygen partial pressure from 0,012 to 0,004 MPa). Quantity of high dencity heat shock proteins (Hsp70) rats motor cortex neurons was 3,44 times higher after course of high pressure nitrogen compression up to 4,1 MPa. For hypoxic exposure (6% O2) the difference was less pronounced - 2,2 times. Data about rat motor cortex neurons Hsp70 concentration under high nitrogen pressure and low oxygen pressure may turn to be a clear base for explanation hypoxic influence on processes of nitrogen narcosis.

  7. Iron fortification of whole wheat flour reduces iron deficiency and iron deficiency anemia and increases body iron stores in Indian school-aged children.

    Science.gov (United States)

    Muthayya, Sumithra; Thankachan, Prashanth; Hirve, Siddhivinayak; Amalrajan, Vani; Thomas, Tinku; Lubree, Himangi; Agarwal, Dhiraj; Srinivasan, Krishnamachari; Hurrell, Richard F; Yajnik, Chittaranjan S; Kurpad, Anura V

    2012-11-01

    Wheat is the primary staple food for nearly one-third of the world's population. NaFeEDTA is the only iron (Fe) compound suitable for fortifying high extraction flours. We tested the hypothesis that NaFeEDTA-fortified, whole wheat flour reduces Fe deficiency (ID) and improves body Fe stores (BIS) and cognitive performance in Indian children. In a randomized, double-blind, controlled, school feeding trial, 6- to 15-y-old, Fe-depleted children (n = 401) were randomly assigned to either a daily wheat-based lunch meal fortified with 6 mg of Fe as NaFeEDTA or an otherwise identical unfortified control meal. Hemoglobin (Hb) and Fe status were measured at baseline, 3.5 mo, and 7 mo. Cognitive performance was evaluated at baseline and 7 mo in children (n = 170) at one of the study sites. After 7 mo, the prevalence of ID and ID anemia in the treatment group significantly decreased from 62 to 21% and 18 to 9%, respectively. There was a time x treatment interaction for Hb, serum ferritin, transferrin receptor, zinc protoporphyrin, and BIS (all P children. It may be recommended for wider use in national school feeding programs.

  8. Effect of increased fuel temperature on emissions of oxides of nitrogen from a gas turbine combustor burning ASTM jet-A fuel

    Science.gov (United States)

    Marchionna, N. R.

    1974-01-01

    An annular gas turbine combustor was tested with heated ASTM Jet-A fuel to determine the effect of increased fuel temperature on the formation of oxides of nitrogen. Fuel temperature ranged from ambient to 700 K. The NOx emission index increased at a rate of 6 percent per 100 K increase in fuel temperature.

  9. Aliskiren attenuates steatohepatitis and increases turnover of hepatic fat in mice fed with a methionine and choline deficient diet.

    Directory of Open Access Journals (Sweden)

    Kuei-Chuan Lee

    Full Text Available BACKGROUND & AIMS: Activation of the renin-angiotensin-system is known to play a role in nonalcoholic steatohepatitis. Renin knockout mice manifest decreased hepatic steatosis. Aliskiren is the first direct renin inhibitor to be approved for clinical use. Our study aims to evaluate the possible therapeutic effects and mechanism of the chronic administration of aliskiren in a dietary steatohepatitis murine model. METHODS: Male C57BL/6 mice were fed with a methionine and choline-deficient (MCD diet to induce steatohepatitis. After 8 weeks of feeding, the injured mice were randomly assigned to receive aliskiren (50 mg·kg(-1 per day or vehicle administration for 4 weeks. Normal controls were also administered aliskiren (50 mg·kg(-1 per day or a vehicle for 4 weeks. RESULTS: In the MCD mice, aliskiren attenuated hepatic steatosis, inflammation and fibrosis. Aliskiren did not change expression of lipogenic genes but increase turnover of hepatic fat by up-regulating peroxisome proliferator-activated receptor α, carnitine palmitoyltransferase 1a, cytochrome P450-4A14 and phosphorylated AMP-activated protein kinase. Furthermore, aliskiren decreased the hepatic expression of angiotensin II and nuclear factor κB. The levels of oxidative stress, hepatocyte apoptosis, activation of Kupffer cells and hepatic stellate cells, and pro-fibrotic markers were also reduced in the livers of the MCD mice receiving aliskiren. CONCLUSIONS: Aliskiren attenuates steatohepatitis and fibrosis in mice fed with a MCD diet. Thus, the noted therapeutic effects might come from not only the reduction of angiotensin II but also the up-regulation of fatty acid oxidation-related genes.

  10. Vitamin A supplementation in early life enhances the intestinal immune response of rats with gestational vitamin A deficiency by increasing the number of immune cells.

    Directory of Open Access Journals (Sweden)

    Xia Liu

    Full Text Available Vitamin A is a critical micronutrient for regulating immunity in many organisms. Our previous study demonstrated that gestational or early-life vitamin A deficiency decreases the number of immune cells in offspring. The present study aims to test whether vitamin A supplementation can restore lymphocyte pools in vitamin A-deficient rats and thereby improve the function of their intestinal mucosa; furthermore, the study aimed to identify the best time frame for vitamin A supplementation. Vitamin A-deficient pregnant rats or their offspring were administered a low-dose of vitamin A daily for 7 days starting on gestational day 14 or postnatal day 1, day 14 or day 28. Serum retinol concentrations increased significantly in all four groups that received vitamin A supplementation, as determined by high-performance liquid chromatography. The intestinal levels of secretory immunoglobulin A and polymeric immunoglobulin receptor increased significantly with lipopolysaccharide challenge in the rats that received vitamin A supplementation starting on postnatal day 1. The rats in this group had higher numbers of CD8+ intestinal intraepithelial lymphocytes, CD11C+ dendritic cells in the Peyer's patches and CD4+CD25+ T cells in the spleen compared with the vitamin A-deficient rats; flow cytometric analysis also demonstrated that vitamin A supplementation decreased the number of B cells in the mesenteric lymph nodes. Additionally, vitamin A supplementation during late gestation increased the numbers of CD8+ intestinal intraepithelial lymphocytes and decreased the numbers of B lymphocytes in the mesenteric lymph nodes. However, no significant differences in lymphocyte levels were found between the rats in the other two vitamin A supplement groups and the vitamin A-deficient group. In conclusion, the best recovery of a subset of lymphocytes in the offspring of gestational vitamin A-deficient rats and the greatest improvement in the intestinal mucosal immune

  11. PII Overexpression in Lotus japonicus Affects Nodule Activity in Permissive Low-Nitrogen Conditions and Increases Nodule Numbers in High Nitrogen Treated Plants.

    Science.gov (United States)

    D'Apuzzo, Enrica; Valkov, Vladimir Totev; Parlati, Aurora; Omrane, Selim; Barbulova, Ani; Sainz, Maria Martha; Lentini, Marco; Esposito, Sergio; Rogato, Alessandra; Chiurazzi, Maurizio

    2015-04-01

    We report here the first characterization of a GLNB1 gene coding for the PII protein in leguminous plants. The main purpose of this work was the investigation of the possible roles played by this multifunctional protein in nodulation pathways. The Lotus japonicus LjGLB1 gene shows a significant transcriptional regulation during the light-dark cycle and different nitrogen availability, conditions that strongly affect nodule formation, development, and functioning. We also report analysis of the spatial profile of expression of LjGLB1 in root and nodule tissues and of the protein's subcellular localization. Transgenic L. japonicus lines overexpressing the PII protein were obtained and tested for the analysis of the symbiotic responses in different conditions. The uncoupling of PII from its native regulation affects nitrogenase activity and nodule polyamine content. Furthermore, our results suggest the involvement of PII in the signaling of the nitrogen nutritional status affecting the legumes' predisposition for nodule formation.

  12. Effect of foliar feeding on nitrogen assimilation in alfalfa plants at insufficient molybdenum supply.

    Science.gov (United States)

    Hristozkova, Marieta; Geneva, Maria; Stancheva, Ira

    2009-06-01

    The influence of foliar feeding on the nitrogen assimilation in alfalfa plants under conditions of Mo shortage was studied. It was established that foliar fertilization with 0.3% solution of Agroleaf® resulted in increase of nitrogen fixation and nitrogen assimilation in the absence of Mo. Insufficient molybdenum supply leads to significant reduction of plant Mo content and nitrogen-fixing activity, while stress induced amino acids as alanine, GABA, threonine, proline and serine increased repeatedly. The negative effect of Mo deficiency on the enzyme activities related to the primary nitrogen assimilation (NR, GS, GOGAT) and plant growth diminished due to the foliar absorbed nutrients.

  13. Mesangial cells from patients with IgA nephropathy have increased susceptibility to galactose-deficient IgA1.

    Science.gov (United States)

    Ebefors, Kerstin; Liu, Peidi; Lassén, Emelie; Elvin, Johannes; Candemark, Emma; Levan, Kristina; Haraldsson, Börje; Nyström, Jenny

    2016-04-05

    IgA nephropathy (IgAN) is the most common glomerulonephritis in the world, affecting close to a million people. Circulating galactose-deficient IgA (gd-IgA), present in patients with IgAN, form immune complex deposits in the glomerular mesangium causing local proliferation and matrix expansion. Intriguing though, individuals having gd-IgA deposits in the kidneys do not necessarily have signs of glomerular disease. Recurrence of IgAN only occurs in less than half of transplanted patients with IgAN, indicating that gd-IgA is not the only factor driving the disease. We hypothesize that, in addition to IgA complexes, patients with IgAN possess a subtype of mesangial cells highly susceptible to gd-IgA induced cell proliferation. To test the hypothesis, we designed a technique to culture primary mesangial cells from renal biopsies obtained from IgAN patients and controls. The cell response to gd-IgA treatment was then measured both on gene and protein level and the proliferation rate of the cells in response to PDGF was investigated. When treated with gd-IgA, mesangial cells from patients with IgAN express and release more PDGF compared to controls. In addition, the mesangial cells from patients with IgAN were more responsive to treatment with PDGF resulting in an increased proliferation rate of the cells compared to control. Mesangial cells cultured from patients with IgAN expressed and released more IL-6 than controls and had a higher expression of matrix genes. Both mesangial cells derived from patients with IgAN and controls increased their expressed TGFβ1 and CCL5 when treated with gd-IgA. We conclude that mesangial cells derived from IgAN patients have a mesangioproliferative phenotype with increased reactivity to IgA and that these cellular intrinsic properties may be important for the development of IgA nephropathy.

  14. The effect of increasing salinity and forest mortality on soil nitrogen and phosphorus mineralization in tidal freshwater forested wetlands

    Science.gov (United States)

    Noe, Gregory B.; Krauss, Ken W.; Lockaby, B. Graeme; Conner, William H.; Hupp, Cliff R.

    2013-01-01

    Tidal freshwater wetlands are sensitive to sea level rise and increased salinity, although little information is known about the impact of salinification on nutrient biogeochemistry in tidal freshwater forested wetlands. We quantified soil nitrogen (N) and phosphorus (P) mineralization using seasonal in situ incubations of modified resin cores along spatial gradients of chronic salinification (from continuously freshwater tidal forest to salt impacted tidal forest to oligohaline marsh) and in hummocks and hollows of the continuously freshwater tidal forest along the blackwater Waccamaw River and alluvial Savannah River. Salinification increased rates of net N and P mineralization fluxes and turnover in tidal freshwater forested wetland soils, most likely through tree stress and senescence (for N) and conversion to oligohaline marsh (for P). Stimulation of N and P mineralization by chronic salinification was apparently unrelated to inputs of sulfate (for N and P) or direct effects of increased soil conductivity (for N). In addition, the tidal wetland soils of the alluvial river mineralized more P relative to N than the blackwater river. Finally, hummocks had much greater nitrification fluxes than hollows at the continuously freshwater tidal forested wetland sites. These findings add to knowledge of the responses of tidal freshwater ecosystems to sea level rise and salinification that is necessary to predict the consequences of state changes in coastal ecosystem structure and function due to global change, including potential impacts on estuarine eutrophication.

  15. Hydrologic connectivity to streams increases nitrogen and phosphorus inputs and cycling in soils of created and natural floodplain wetlands.

    Science.gov (United States)

    Wolf, Kristin L; Noe, Gregory B; Ahn, Changwoo

    2013-07-01

    Greater connectivity to stream surface water may result in greater inputs of allochthonous nutrients that could stimulate internal nitrogen (N) and phosphorus (P) cycling in natural, restored, and created riparian wetlands. This study investigated the effects of hydrologic connectivity to stream water on soil nutrient fluxes in plots ( = 20) located among four created and two natural freshwater wetlands of varying hydrology in the Piedmont physiographic province of Virginia. Surface water was slightly deeper; hydrologic inputs of sediment, sediment-N, and ammonium were greater; and soil net ammonification, N mineralization, and N turnover were greater in plots with stream water classified as their primary water source compared with plots with precipitation or groundwater as their primary water source. Soil water-filled pore space, inputs of nitrate, and soil net nitrification, P mineralization, and denitrification enzyme activity (DEA) were similar among plots. Soil ammonification, N mineralization, and N turnover rates increased with the loading rate of ammonium to the soil surface. Phosphorus mineralization and ammonification also increased with sedimentation and sediment-N loading rate. Nitrification flux and DEA were positively associated in these wetlands. In conclusion, hydrologic connectivity to stream water increased allochthonous inputs that stimulated soil N and P cycling and that likely led to greater retention of sediment and nutrients in created and natural wetlands. Our findings suggest that wetland creation and restoration projects should be designed to allow connectivity with stream water if the goal is to optimize the function of water quality improvement in a watershed.

  16. Munc18b Increases Insulin Granule Fusion, Restoring Deficient Insulin Secretion in Type-2 Diabetes Human and Goto-Kakizaki Rat Islets with Improvement in Glucose Homeostasis

    Directory of Open Access Journals (Sweden)

    Tairan Qin

    2017-02-01

    Infusion of Ad-Munc18b into GK rat pancreas led to sustained improvement in glucose homeostasis. However, Munc18b overexpression in normal islets increased only newcomer SG fusion. Therefore, Munc18b could potentially be deployed in human T2D to rescue the deficient GSIS.

  17. MBL2 gene variants coding for mannose-binding lectin deficiency are associated with increased risk of nephritis in Danish patients with systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Tanha, N; Troelsen, L; From Hermansen, M-L;

    2014-01-01

    OBJECTIVES: Autoimmunity may in part result from deficiencies in the processing of apoptotic debris. As mannose-binding lectin (MBL) is involved in such processes, we hypothesized that the variants in the MBL2 gene resulting in MBL deficiency confer an increased risk of nephritis in systemic lupus...... erythematosus (SLE). METHODS: A total of 171 SLE patients attending a Danish tertiary rheumatology referral center were included. Common variant alleles in exon 1 of the MBL2 gene (R52C, rs5030737; G54D, rs1800450; G57E, rs1800451) were genotyped. The normal allele and variant alleles are termed A and O...

  18. The glycolytic shift in fumarate-hydratase-deficient kidney cancer lowers AMPK levels, increases anabolic propensities and lowers cellular iron levels

    KAUST Repository

    Tong, Winghang

    2011-09-01

    Inactivation of the TCA cycle enzyme, fumarate hydratase (FH), drives a metabolic shift to aerobic glycolysis in FH-deficient kidney tumors and cell lines from patients with hereditary leiomyomatosis renal cell cancer (HLRCC), resulting in decreased levels of AMP-activated kinase (AMPK) and p53 tumor suppressor, and activation of the anabolic factors, acetyl-CoA carboxylase and ribosomal protein S6. Reduced AMPK levels lead to diminished expression of the DMT1 iron transporter, and the resulting cytosolic iron deficiency activates the iron regulatory proteins, IRP1 and IRP2, and increases expression of the hypoxia inducible factor HIF-1α, but not HIF-2α. Silencing of HIF-1α or activation of AMPK diminishes invasive activities, indicating that alterations of HIF-1α and AMPK contribute to the oncogenic growth of FH-deficient cells. © 2011 Elsevier Inc.

  19. Vitamin D Receptor Ablation and Vitamin D Deficiency Result in Reduced Grip Strength, Altered Muscle Fibers, and Increased Myostatin in Mice.

    Science.gov (United States)

    Girgis, Christian M; Cha, Kuan Minn; Houweling, Peter J; Rao, Renuka; Mokbel, Nancy; Lin, Mike; Clifton-Bligh, Roderick J; Gunton, Jenny E

    2015-12-01

    Vitamin D deficiency is associated with muscle weakness, pain, and atrophy. Serum vitamin D predicts muscle strength and age-related muscle changes. However, precise mechanisms by which vitamin D affects skeletal muscle are unclear. To address this question, this study characterizes the muscle phenotype and gene expression of mice with deletion of vitamin D receptor (VDRKO) or diet-induced vitamin D deficiency. VDRKO and vitamin D-deficient mice had significantly weaker grip strength than their controls. Weakness progressed with age and duration of vitamin D deficiency, respectively. Histological assessment showed that VDRKO mice had muscle fibers that were significantly smaller in size and displayed hyper-nuclearity. Real-time PCR also indicated muscle developmental changes in VDRKO mice with dysregulation of myogenic regulatory factors (MRFs) and increased myostatin in quadriceps muscle (>2-fold). Vitamin D-deficient mice also showed increases in myostatin and the atrophy marker E3-ubiqutin ligase MuRF1. As a potential explanation for grip strength weakness, both groups of mice had down-regulation of genes encoding calcium-handling and sarco-endoplasmic reticulum calcium transport ATPase (Serca) channels. This is the first report of reduced strength, morphological, and gene expression changes in VDRKO and vitamin D-deficient mice where confounding by calcium, magnesium, and phosphate have been excluded by direct testing. Although suggested in earlier in vitro work, this study is the first to report an in vivo association between vitamin D, myostatin, and the regulation of muscle mass. These findings support a direct role for vitamin D in muscle function and corroborate earlier work on the presence of VDR in this tissue.

  20. Glucose-6-phosphate dehydrogenase deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2.

    Science.gov (United States)

    Roshankhah, Shiva; Rostami-Far, Zahra; Shaveisi-Zadeh, Farhad; Movafagh, Abolfazl; Bakhtiari, Mitra; Shaveisi-Zadeh, Jila

    2016-12-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. G6PD plays a key role in the pentose phosphate pathway, which is a major source of nicotinamide adenine dinucleotide phosphate (NADPH). NADPH provides the reducing equivalents for oxidation-reduction reductions involved in protecting against the toxicity of reactive oxygen species such as H2O2. We hypothesized that G6PD deficiency may reduce the amount of NADPH in sperms, thereby inhibiting the detoxification of H2O2, which could potentially affect their motility and viability, resulting in an increased susceptibility to infertility. Semen samples were obtained from four males with G6PD deficiency and eight healthy males as a control. In both groups, motile sperms were isolated from the seminal fluid and incubated with 0, 10, 20, 40, 60, 80, and 120 µM concentrations of H2O2. After 1 hour incubation at 37℃, sperms were evaluated for motility and viability. Incubation of sperms with 10 and 20 µM H2O2 led to very little decrease in motility and viability, but motility decreased notably in both groups in 40, 60, and 80 µM H2O2, and viability decreased in both groups in 40, 60, 80, and 120 µM H2O2. However, no statistically significant differences were found between the G6PD-deficient group and controls. G6PD deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2, and the reducing equivalents necessary for protection against H2O2 are most likely produced by other pathways. Therefore, G6PD deficiency cannot be considered as major risk factor for male infertility.

  1. Vitamin A deficiency decreases and high dietary vitamin A increases disease severity in the mouse model of asthma

    Science.gov (United States)

    The Th1/ Th2 paradigm has become an important issue in the pathogenesis of asthma, characterized by normal Th-1 and elevated Th-2 cytokine expression, resulting in a Th2 predominance. Vitamin A deficiency (VAD) produces a significant Th1 bias, while high-level dietary vitamin A supplementation promo...

  2. Increasing fat in the diet does not improve muscle performance in patients with mitochondrial myopathy due to complex I deficiency

    NARCIS (Netherlands)

    de Meer, K; Roef, MJ; de Klerk, JBC; Bakker, HD; Smit, GPA; Poll-The, BT

    2005-01-01

    Four myopathic patients with complex I deficiency followed diets containing 55 energy per cent (En%) as fat or 25 En% as fat, both for three weeks. Maximal workload and muscle force were not different on either diet. Exercise endurance time, oxygen consumption and lactate levels were also not differ

  3. Lactate disposal via gluconeogenesis is increased during exercise in patients with mitochondrial myopathy due to complex I deficiency

    NARCIS (Netherlands)

    Roef, MJ; Kalhan, SC; Reijngoud, DJ; De Meer, K; Berger, Ruud

    2002-01-01

    This study evaluated lactate disposal via gluconeogenesis as well as effects of FFA availability on gluconeogenesis via pyruvate (GNG(PYR)) in patients with mitochondrial myopathy due to complex I deficiency (CID). The rates of GNG(PYR) were measured in three CID patients and six healthy controls at

  4. Increase in maternal placental growth hormone during pregnancy and disappearance during parturition in normal and growth hormone-deficient pregnancies

    DEFF Research Database (Denmark)

    Lønberg, Ulla; Damm, Peter; Andersson, Anna-Maria

    2003-01-01

    The purpose of this study was to evaluate placental growth hormone levels in maternal circulation throughout pregnancy in normal and growth hormone-deficient women with the use of a specific assay and to determine the clearance of placental growth hormone from maternal circulation after birth....

  5. Effects of increased nitrogen deposition and rotation length on long-term productivity of Cunninghamia lanceolata plantation in southern China.

    Science.gov (United States)

    Zhao, Meifang; Xiang, Wenhua; Tian, Dalun; Deng, Xiangwen; Huang, Zhihong; Zhou, Xiaolu; Peng, Changhui

    2013-01-01

    Cunninghamia lanceolata (Lamb.) Hook. has been widely planted in subtropical China to meet increasing timber demands, leading to short-rotation practices that deplete soil nutrients. However, increased nitrogen (N) deposition offsets soil N depletion. While long-term experimental data investigating the coupled effects related to short rotation practices and increasing N deposition are scarce, applying model simulations may yield insights. In this study, the CenW3.1 model was validated and parameterized using data from pure C. lanceolata plantations. The model was then used to simulate various changes in long-term productivity. Results indicated that responses of productivity of C. lanceolata plantation to increased N deposition were more related to stand age than N addition, depending on the proportion and age of growing forests. Our results have also shown a rapid peak in growth and N dynamics. The peak is reached sooner and is higher under higher level of N deposition. Short rotation lengths had a greater effect on productivity and N dynamics than high N deposition levels. Productivity and N dynamics decreased as the rotation length decreased. Total productivity levels suggest that a 30-year rotation length maximizes productivity at the 4.9 kg N ha(-1) year(-1) deposition level. For a specific rotation length, higher N deposition levels resulted in greater overall ecosystem C and N storage, but this positive correlation tendency gradually slowed down with increasing N deposition levels. More pronounced differences in N deposition levels occurred as rotation length decreased. To sustain C. lanceolata plantation productivity without offsite detrimental N effects, the appropriate rotation length is about 20-30 years for N deposition levels below 50 kg N ha(-1) year(-1) and about 15-20 years for N deposition levels above 50 kg N ha(-1) year(-1). These results highlight the importance of assessing N effects on carbon management and the long-term productivity of forest

  6. Effects of increased nitrogen deposition and rotation length on long-term productivity of Cunninghamia lanceolata plantation in southern China.

    Directory of Open Access Journals (Sweden)

    Meifang Zhao

    Full Text Available Cunninghamia lanceolata (Lamb. Hook. has been widely planted in subtropical China to meet increasing timber demands, leading to short-rotation practices that deplete soil nutrients. However, increased nitrogen (N deposition offsets soil N depletion. While long-term experimental data investigating the coupled effects related to short rotation practices and increasing N deposition are scarce, applying model simulations may yield insights. In this study, the CenW3.1 model was validated and parameterized using data from pure C. lanceolata plantations. The model was then used to simulate various changes in long-term productivity. Results indicated that responses of productivity of C. lanceolata plantation to increased N deposition were more related to stand age than N addition, depending on the proportion and age of growing forests. Our results have also shown a rapid peak in growth and N dynamics. The peak is reached sooner and is higher under higher level of N deposition. Short rotation lengths had a greater effect on productivity and N dynamics than high N deposition levels. Productivity and N dynamics decreased as the rotation length decreased. Total productivity levels suggest that a 30-year rotation length maximizes productivity at the 4.9 kg N ha(-1 year(-1 deposition level. For a specific rotation length, higher N deposition levels resulted in greater overall ecosystem C and N storage, but this positive correlation tendency gradually slowed down with increasing N deposition levels. More pronounced differences in N deposition levels occurred as rotation length decreased. To sustain C. lanceolata plantation productivity without offsite detrimental N effects, the appropriate rotation length is about 20-30 years for N deposition levels below 50 kg N ha(-1 year(-1 and about 15-20 years for N deposition levels above 50 kg N ha(-1 year(-1. These results highlight the importance of assessing N effects on carbon management and the long

  7. Subalpine grassland carbon dioxide fluxes indicate substantial carbon losses under increased nitrogen deposition, but not at elevated ozone concentration

    Science.gov (United States)

    Volk, Matthias; Obrist, Daniel; Novak, Kris; Giger, Robin; Bassin, Seraina; Fuhrer, Jürg

    2010-05-01

    Ozone (O3) and nitrogen (N) deposition affect plant carbon (C) dynamics and may thus change ecosystem C-sink/-source properties. We studied effects of increased background O3 concentrations (up to ambient x 2) and increased N deposition (up to +50 kg ha-1 a-1) on mature, subalpine grassland during the third treatment year. During ten days and 13 nights, covering the vegetation period of 2006, we measured ecosystem-level CO2 exchange using a steady state cuvette. Light dependency of gross primary production (GPP) and temperature dependency of ecosystem respiration rates (Reco) were established. Soil temperature, soil water content, and solar radiation were monitored. Using Reco and GPP values, we calculated seasonal net ecosystem production (NEP), based on hourly averages of global radiation and soil temperature. Differences in NEP were compared to differences in soil organic C after five years of treatment. Under high O3 and with unchanged aboveground biomass, both mean Reco and GPP decreased throughout the season. Thus, NEP indicated an unaltered growing season CO2-C balance. Under high N treatment, with a +31% increase in aboveground productivity, mean Reco, but not GPP increased. Consequently, seasonal NEP yielded a 53.9 g C m-2 (± 22.05) C loss compared to control. Independent of treatment, we observed a negative NEP of 146.4 g C m-2 (±15.3). This C loss was likely due to a transient management effect, equivalent to a shift from pasture to hay meadow and a drought effect, specific to the 2006 summer climate. We argue that this resulted from strongly intensified soil microbial respiration, following mitigation of nutrient limitation. There was no interaction between O3 and N treatments. Thus, during the 2006 growing season, the subalpine grassland lost >2% of total topsoil organic C as respired CO2, with increased N deposition responsible for one-third of that loss.

  8. Low-dose irradiation prior to bone marrow transplantation results in ATM activation and increased lethality in Atm-deficient mice.

    Science.gov (United States)

    Pietzner, J; Merscher, B M; Baer, P C; Duecker, R P; Eickmeier, O; Fußbroich, D; Bader, P; Del Turco, D; Henschler, R; Zielen, S; Schubert, R

    2016-04-01

    Ataxia telangiectasia is a genetic instability syndrome characterized by neurodegeneration, immunodeficiency, severe bronchial complications, hypersensitivity to radiotherapy and an elevated risk of malignancies. Repopulation with ATM-competent bone marrow-derived cells (BMDCs) significantly prolonged the lifespan and improved the phenotype of Atm-deficient mice. The aim of the present study was to promote BMDC engraftment after bone marrow transplantation using low-dose irradiation (IR) as a co-conditioning strategy. Atm-deficient mice were transplanted with green fluorescent protein-expressing, ATM-positive BMDCs using a clinically relevant non-myeloablative host-conditioning regimen together with TBI (0.2-2.0 Gy). IR significantly improved the engraftment of BMDCs into the bone marrow, blood, spleen and lung in a dose-dependent manner, but not into the cerebellum. However, with increasing doses, IR lethality increased even after low-dose IR. Analysis of the bronchoalveolar lavage fluid and lung histochemistry revealed a significant enhancement in the number of inflammatory cells and oxidative damage. A delay in the resolution of γ-H2AX-expression points to an insufficient double-strand break repair capacity following IR with 0.5 Gy in Atm-deficient splenocytes. Our results demonstrate that even low-dose IR results in ATM activation. In the absence of ATM, low-dose IR leads to increased inflammation, oxidative stress and lethality in the Atm-deficient mouse model.

  9. Increasing the durability of Li-ion batteries by means of manganese ion trapping materials with nitrogen functionalities

    Science.gov (United States)

    Banerjee, Anjan; Ziv, Baruch; Luski, Shalom; Aurbach, Doron; Halalay, Ion C.

    2017-02-01

    Manganese dissolution from positive electrodes seriously reduces the useful life of Li-ion batteries, especially with positive electrode materials having spinel phases. We show herein that Mn ion trapping separators containing inexpensive mass-produced materials may dramatically increase the life of Li-ion batteries. LiMn2O4-graphite cells containing these materials and a LiPF6 based electrolyte solution display excellent capacity retention during cycling at both room and elevated temperatures, over baseline cells with plain separators. After 30 days of cycling at 55 °C and C/5 rate, LiMn2O4-graphite cells containing three different Mn-trapping materials with nitrogen functionalities retain between 75% and 125% more of the initial capacity than the baseline cells. Mn amounts in graphite negative electrodes from cells with the functional separators are 13-21 times lower than in baseline cells. LiMn2O4 lattice shrinkage in cells with functionalized separators is negligible compared to baseline cells, indicating major reductions in the loss of electrochemically active Li+ ions and increased stability of the LiMn2O4 crystal lattice.

  10. Mixtures of Complete and pif1- and pif2-Deficient Genotypes Are Required for Increased Potency of an Insect Nucleopolyhedrovirus▿

    Science.gov (United States)

    Clavijo, Gabriel; Williams, Trevor; Simón, Oihane; Muñoz, Delia; Cerutti, Martine; López-Ferber, Miguel; Caballero, Primitivo

    2009-01-01

    NIC-BΔ16K. Nearly identical results were observed in peroral-passage experiments involving mixtures of SfNIC-B plus SfNIC-BΔpifs. We conclude that (i) the deletion of the pif1 and pif2 region is necessary and sufficient to explain the increased potency observed in mixtures of complete and deletion genotypes and (ii) viral populations with decreased ratios of pif1- and pif2-deficient genotypes in the virus population increase the potency of genotypic mixtures and are likely to positively influence the transmission of this pathogen. PMID:19264787

  11. Effects of Nitrogen Deficiency on the Photosynthetic Characteristics of Different Varieties of Japonica Rice%缺氮对不同粳稻品种光合特性的影响

    Institute of Scientific and Technical Information of China (English)

    吴言; 唐宁; 张边江

    2014-01-01

    Using 9516,Wuyujing, Zhendao8, Kitaake as materials, effects of nitrogen deficiency on the photosynthetic characteristics of different varieties of japonica rice were studied. The chlorophyll content,root-shoot ratio, photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 (Ci) and transpiration rate (E) were studied. The results showed that chlorophyll content,Pn,Gs and E was decreased significantly in rice under nitrogen deficiency. Root-shoot ratio and Ci was higher than that of control. Nitrogen deficiency had some effects on chlorophyll biosynthesis. The Pn of rice was decreased significantly. Dry matter accumulation was decreased significantly. Rrice root-shoot ratio was improved. Nitrogen was one of the necessary element for rice growth. The results will provide theoretic basis and technical approach for nitrogen use.%为了研究缺氮对不同水稻(Oryza sativa L.)品种光合特性的影响,以9516、武育粳、镇稻8号、Kitaake 4种粳稻为材料,测定氮素缺乏营养液(缺氮处理组)和完全营养液(对照)处理下水稻幼苗的叶绿素含量(以叶绿素SPAD值表示)、根冠比以及水稻的光合生理相关指标。结果表明,缺氮处理后水稻叶绿素含量、净光合速率、蒸腾速率和气孔导度均低于对照,而根冠比和胞间CO2浓度高于对照,表明缺氮影响了水稻的叶绿素合成,导致水稻的光合速率降低,干物质积累变少,根冠比升高。

  12. The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review

    Science.gov (United States)

    Riitta Hyvönen; Göran I. Ågren; Sune Linder; Tryggve Persson; M. Francesca Cotrufo; Alf Ekblad; Michael Freeman; Achim Grelle; Ivan A. Janssens; Paul G. Jarvis; Seppo Kellomäki; Anders Lindroth; Denis Loustau; Tomas Lundmark; Richard J. Norby; Ram Oren; Kim Pilegaard; Michael G. Ryan; Bjarni D. Sigurdsson; Monika Strömgren; Marcel van Oijen; Göran Wallin

    2007-01-01

    Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic...

  13. Global climate change will increase the abundance of symbiotic nitrogen-fixing trees in much of North America.

    Science.gov (United States)

    Liao, Wenying; Menge, Duncan N L; Lichstein, Jeremy W; Ángeles-Pérez, Gregorio

    2017-11-01

    Symbiotic nitrogen (N)-fixing trees can drive N and carbon cycling and thus are critical components of future climate projections. Despite detailed understanding of how climate influences N-fixation enzyme activity and physiology, comparatively little is known about how climate influences N-fixing tree abundance. Here, we used forest inventory data from the USA and Mexico (>125,000 plots) along with climate data to address two questions: (1) How does the abundance distribution of N-fixing trees (rhizobial, actinorhizal, and both types together) vary with mean annual temperature (MAT) and precipitation (MAP)? (2) How will changing climate shift the abundance distribution of N-fixing trees? We found that rhizobial N-fixing trees were nearly absent below 15°C MAT, but above 15°C MAT, they increased in abundance as temperature rose. We found no evidence for a hump-shaped response to temperature throughout the range of our data. Rhizobial trees were more abundant in dry than in wet ecosystems. By contrast, actinorhizal trees peaked in abundance at 5-10°C MAT and were least abundant in areas with intermediate precipitation. Next, we used a climate-envelope approach to project how N-fixing tree relative abundance might change in the future. The climate-envelope projection showed that rhizobial N-fixing trees will likely become more abundant in many areas by 2080, particularly in the southern USA and western Mexico, due primarily to rising temperatures. Projections for actinorhizal N-fixing trees were more nuanced due to their nonmonotonic dependence on temperature and precipitation. Overall, the dominant trend is that warming will increase N-fixing tree abundance in much of the USA and Mexico, with large increases up to 40° North latitude. The quantitative link we provide between climate and N-fixing tree abundance can help improve the representation of symbiotic N fixation in Earth System Models. © 2017 John Wiley & Sons Ltd.

  14. Nitrogen fertilizer increases nitrous oxide, but not dinitrogen, emissions from moist tropical forest soils in Puerto Rico

    Science.gov (United States)

    Almaraz, M.; Porder, S.; Groffman, P. M.

    2015-12-01

    Nitrogen (N) deposition in tropical forests may increase substantially in coming decades, stimulating a concomitant increase of soil N gas emissions (dinitrogen (N2), nitrous (N2O) and nitric oxides). How N deposition might alter the relative emissions of these gases is unclear, and has ramifications for the global climate since N2O is a potent greenhouse gas. We used a small-scale fertilization study in the Luquillo Experimental Forest (LEF) of Puerto Rico to simulate the effects of N deposition on N gas emissions. Fertilizer was applied by placing mesh bags filled with ammonium saturated weak cation exchange resin directly on the mineral soil for two months. At that time, intact soil cores (0-10cm) were taken from below the bags. The cores were shipped to the Cary Institute of Ecosystem Studies, where they were incubated in a helium headspace with either 0 or 20% oxygen (O2), and analyzed for N2 and N2O emissions. N fertilization increased N2O emissions fourfold (p=0.03). N2O production was positively correlated with field soil moisture (r=0.45, p=0.002), and was higher under 20% than 0% atmospheric O2 (p=0.003). With the exception of a handful of samples, we detected no measureable N2 production from these soils, and fertilization did not influence N2 production. This may have been because our experiment occurred during a drought that reduced soil moisture in the field by ˜20%. We have found that N2 emissions correlate with soil moisture elsewhere in the LEF. While we conclude that N deposition may not influence the N2O:N2 of soil emissions under such conditions, it is still unclear whether this result would hold under higher rainfall.

  15. Telomerase-Deficient Mice Exhibit Bone Loss Owing to Defects in Osteoblasts and Increased Osteoclastogenesis by Inflammatory Microenvironment

    DEFF Research Database (Denmark)

    Saeed, H.; Abdallah, B. M.; Ditzel, N.

    2011-01-01

    Telomere shortening owing to telomerase deficiency leads to accelerated senescence of human skeletal (mesenchymal) stem cells (MSCs) in vitro, whereas overexpression leads to telomere elongation, extended life span, and enhanced bone formation. To study the role of telomere shortening in vivo, we...... osteoblastic defects and creation of a proinflammatory osteoclast-activating microenvironment. Thus telonnerization of MSCs may provide a novel approach for abolishing age-related bone loss. (C) 2011 American Society for Bone and Mineral Research....

  16. Improved Alkane Production in Nitrogen-Fixing and Halotolerant Cyanobacteria via Abiotic Stresses and Genetic Manipulation of Alkane Synthetic Genes.

    Science.gov (United States)

    Kageyama, Hakuto; Waditee-Sirisattha, Rungaroon; Sirisattha, Sophon; Tanaka, Yoshito; Mahakhant, Aparat; Takabe, Teruhiro

    2015-07-01

    Cyanobacteria possess the unique capacity to produce alkane. In this study, effects of nitrogen deficiency and salt stress on biosynthesis of alkanes were investigated in three kinds of cyanobacteria. Intracellular alkane accumulation was increased in nitrogen-fixing cyanobacterium Anabaena sp. PCC7120, but decreased in non-diazotrophic cyanobacterium Synechococcus elongatus PCC7942 and constant in a halotolerant cyanobacterium Aphanothece halophytica under nitrogen-deficient condition. We also found that salt stress increased alkane accumulation in Anabaena sp. PCC7120 and A. halophytica. The expression levels of two alkane synthetic genes were not upregulated significantly under nitrogen deficiency or salt stress in Anabaena sp. PCC7120. The transformant Anabaena sp. PCC7120 cells with additional alkane synthetic gene set from A. halophytica increased intracellular alkane accumulation level compared to control cells. These results provide a prospect to improve bioproduction of alkanes in nitrogen-fixing halotolerant cyanobacteria via abiotic stresses and genetic engineering.

  17. 低合金钢冶炼过程增氮行为分析%Behavior Analysis of Nitrogen Content Increasing in Low Alloy Steel Smelting Process

    Institute of Scientific and Technical Information of China (English)

    张帆; 范植金; 丁礼权

    2014-01-01

    为提高中厚板系列低合金钢氮含量控制水平,从热力学、动力学角度全面分析冶炼过程增氮行为,并结合相关试验对影响钢液增氮的因素进行分析。结果表明,氮在钢液中的溶解度与温度、氮分压以及合金成分有关;气泡—钢液面上的吸附化学反应为限制性环节;当钢液中w(O)≥0.04%或w(S)≥0.06%,钢液吸氮基本停止;当转炉全程底吹氮强度不超过0.025 m3/(min·t)时,转炉终点氮含量可控制在10×10-6以内。%In order to improve the level of nitrogen content control of low alloy steel, the paper analyzed the behavior of nitrogen content increasing from the perspective of thermodynamics and kinetics, and illustrated the factors with related experiment. The results show that, the nitrogen solubility in liquid steel relate to temperature, nitrogen partial pressure and alloy composition;bubbles-liquid steel surface chemical reaction is restrictive link; when w(O) ≥0.04% or w(S) ≥0.06% , the increasing nitrogen process of liquid steel stopped; when the whole strength of bottom blowing nitrogen of BOF is no more than 0.025 m3/(min·t), nitrogen content of converter can be controlled within 10×10-6.

  18. Increased de novo riboflavin synthesis and hydrolysis of FMN are involved in riboflavin secretion from Hyoscyamus albus hairy roots under iron deficiency.

    Science.gov (United States)

    Higa, Ataru; Khandakar, Jebunnahar; Mori, Yuko; Kitamura, Yoshie

    2012-09-01

    Riboflavin secretion by Hyoscyamus albus hairy roots under Fe deficiency was examined to determine where riboflavin is produced and whether production occurs via an enhancement of riboflavin biosynthesis or a stimulation of flavin mononucleotide (FMN) hydrolysis. Confocal fluorescent microscopy showed that riboflavin was mainly localized in the epidermis and cortex of the root tip and, at the cellular level, in the apoplast. The expressions of three genes involved in the de novo biosynthesis of riboflavin (GTP cyclohydrolase II/3,4-dihydroxy-2-butanone 4-phosphate synthase; 6,7-dimethyl-8-ribityllumazine synthase; riboflavin synthase) were compared between Fe-starved and Fe-replete roots over a time-course of 7 days, using RT-PCR. All three genes were found to be highly expressed over the period 1-7 days in the roots cultured under Fe deficiency. Since riboflavin secretion began to be detected only from 3 days, there was a lag phase observed between the increased transcript accumulations and riboflavin secretion. To determine whether FMN hydrolysis might contribute to the riboflavin secretion in Fe-deficient root cultures, FMN hydrolase activity was determined and was found to be substantially increased after 3 days, when riboflavin secretion became detectable. These results suggested that not only de novo riboflavin synthesis but also the hydrolysis of FMN contributes to riboflavin secretion under conditions of Fe deficiency. Respiration activity was assayed during the time-course, and was also found to be enhanced after 3 days under Fe deficiency, suggesting a possible link with riboflavin secretion. On the other hand, several respiratory inhibitors were found not to affect riboflavin synthase transcript accumulation.

  19. Growth Promotion, Increase of Iron, Potassium and Cell Wall Components following Silicon Application in Rice under Iron Deficiency

    OpenAIRE

    z Kiani Chalmardi; Ahmad Abdolzadeh; Hamid Reza Sadeghipour

    2014-01-01

    Iron deficiency is one of the most important stress reducing crop growth and yields. Silicon is also an essential element in most grasses including rice that may reduces biotic and abiotic stresses. In present study, the interactions of silicon and iron nutrition were studied in rice (Oryza sativa L. cv. Tarem). The plants cultivated in greenhouse under iron treatments of 0, 2 and 10 mg l-1 as a Fe-EDTA (first factor) and silicon treatments of 0 and 1.5 mM sodium silicate (second factor). The...

  20. Surfactant protein d deficiency in mice is associated with hyperphagia, altered fat deposition, insulin resistance, and increased Basal endotoxemia

    DEFF Research Database (Denmark)

    Stidsen, Jacob V; Khorooshi, Reza; Rahbek, Martin K U

    2012-01-01

    Pulmonary surfactant protein D (SP-D) is a host defence lectin of the innate immune system that enhances clearance of pathogens and modulates inflammatory responses. Recently it has been found that systemic SP-D is associated with metabolic disturbances and that SP-D deficient mice are mildly obese...... with elevated levels of systemic bacterial lipopolysaccharide.In conclusion, our findings suggest that lack of SP-D mediates modulation of food intake not directly involving hypothalamic regulatory pathways. The resulting accumulation of adipose tissue was associated with insulin resistance. The data suggest SP...

  1. Growth and nitrogen fixation of legumes at increased salinity under field conditions: implications for the use of green manures in saline environments

    NARCIS (Netherlands)

    Bruning, B.; van Logtestijn, R.; Broekman, R.; de Vos, A.; Parra Gonzàlez, A.; Rozema, J.

    2015-01-01

    The use of legumes as green manure can potentially increase crop productivity in saline environmentsand thus contribute to the sustainability of agricultural systems. Here, we present results from a field experimentconducted in the Netherlands that addressed the efficiency of nitrogen (N) fixation b

  2. An Assessment of the Variation of Manure Nitrogen Efficiency Throughout Europe and an Appraisal of Means to Increase Manure N Efficiency

    DEFF Research Database (Denmark)

    Webb, J.; Sørensen, Peter; Velthof, Gerard

    2013-01-01

    Using the nitrogen (N) in organic manures more effectively reduces losses to the environment. A requirement to take allowance of the N conserved by reduced ammonia (NH3)-emission techniques would increase manure-N efficiency by up to 15%. Covering manure stores and land application of slurry by i...

  3. An assessment of the variation of manure nitrogen efficiency throughout Europe and an appraisal of means to increase manure-N efficiency

    NARCIS (Netherlands)

    Webb, J.; Sorensen, P.; Velthof, G.L.; Amon, B.; Pinto, M.; Rodhe, L.; Salomon, E.; Hutchings, N.; Burczyk, J.; Reid, J.E.

    2013-01-01

    Using the nitrogen (N) in organic manures more effectively reduces losses to the environment. A requirement to take allowance of the N conserved by reduced ammonia (NH3)-emission techniques would increase manure-N efficiency by up to 15%. Covering manure stores and land application of slurry by

  4. Increasing trends of dissolved organic nitrogen (DON) in temperate forests under recovery from acidification in Flanders, Belgium.

    Science.gov (United States)

    Verstraeten, Arne; Verschelde, Pieter; De Vos, Bruno; Neirynck, Johan; Cools, Nathalie; Roskams, Peter; Hens, Maarten; Louette, Gerald; Sleutel, Steven; De Neve, Stefaan

    2016-05-15

    We evaluated trends (2005-2013) and patterns of dissolved organic nitrogen (DON) and its ratio with dissolved organic carbon (DOC), DOC:DON in atmospheric deposition and soil solution of five Level II plots of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) in Flanders, Northern Belgium. The primary aim was to confirm positive postulated trends in DON levels and DOC:DON under on-going recovery from acidification. The DON concentrations (0.95-1.41 mg L(-1)) and fluxes (5.6-8.3 kg ha(-1)y(-1)) in throughfall were about twice as high compared to precipitation in the open field (0.40-0.48 mg L(-1), 3.0-3.9 kg ha(-1)y(-1)). Annual soil profile leaching losses of DON varied between 1.2 and 3.7 kg ha(-1)y(-1). The highest soil DON concentrations and fluxes were observed beneath the O horizon (1.84-2.36 mg L(-1), 10.1-12.3 kg ha(-1)y(-1)). Soil solution concentrations and fluxes of DON showed significant increasing trends. Temporarily soil solution DOC:DON rose following an exceptionally long spring drought in 2007, suggesting an effect of drying and rewetting on DOM composition. Further research is needed to test the dependence of DON and DOC:DON on factors such as latitude, forest cover, length of the growing season, hydrology and topography. Nonetheless, even with considerable variation in soil type, level of base saturation, and soil texture in the five included ICP Forests Level II plots, all data revealed a proportionally larger positive response of DON flux than DOC to recovery from acidification.

  5. Differential gene expression in Rhododendron fortunei roots colonized by an ericoid mycorrhizal fungus and increased nitrogen absorption and plant growth

    Directory of Open Access Journals (Sweden)

    Xiangying Wei

    2016-10-01

    Full Text Available Ericoid mycorrhizal (ERM fungi are specifically symbiotic with plants in the family Ericaceae. Little is known thus far about their symbiotic establishment and subsequent nitrogen (N uptake at the molecular level. The present study devised a system for establishing a symbiotic relationship between Rhododendron fortunei Lindl. and an ERM fungus (Oidiodendron maius var. maius strain Om19, quantified seedling growth and N uptake, and compared transcriptome profiling between colonized and uncolonized roots using RNA-Seq. The Om19 colonization induced 16,892 genes that were differentially expressed in plant roots, of which 14,364 were upregulated and 2,528 were downregulated. These genes included those homologous to ATP-binding cassette transporters, calcium/calmodulin-dependent kinases, and symbiosis receptor-like kinases. N metabolism was particularly active in Om19-colonized roots, and 51 genes were upregulated, such as nitrate transporters, nitrate reductase, nitrite reductase, ammonium transporters, glutamine synthetase, and glutamate synthase. Transcriptome analysis also identified a series of genes involving endocytosis, Fc-gamma R-mediated phagocytosis, glycerophospholipid metabolism, and GnRH signal pathway that have not been reported previously. Their roles in the symbiosis require further investigation. The Om19 colonization significantly increased N uptake and seedling growth. Total N content and dry weight of colonized seedlings were 36.6% and 46.6% greater than control seedlings. This is the first transcriptome analysis of a species from the family Ericaceae colonized by an ERM fungus. The findings from this study will shed light on the mechanisms underlying symbiotic relationships of ericaceous species with ERM fungi and the symbiosis-resultant N uptake and plant growth.

  6. Increasing microbial diversity and nitrogen cycling potential of burnt forest soil in Spain through post-fire management

    Science.gov (United States)

    Pereg, Lily; Mataix-Solera, Jorge; McMillan, Mary; García-Orenes, Fuensanta

    2016-04-01

    Microbial diversity and function in soils are increasingly assessed by the application of molecular methods such as sequencing and PCR technology. We applied these techniques to study microbial recovery in post-fire forest soils. The recovery of forest ecosystems following severe fire is influenced by post-fire management. The removal of burnt tree stumps (salvage logging) is a common practice in Spain following fire. In some cases, the use of heavy machinery in addition to the vulnerability of soils to erosion and degradation make this management potentially damaging to soil, and therefore to the ecosystem. We hypothesized that tree removal slows down the recovery of soil biological communities including microbial and plant communities and contributes to soil degradation in the burnt affected area. The study area is located in "Sierra de Mariola Natural Park" in Alcoi, Alicante (E Spain). A big forest fire (>500 has) occurred in July 2012. The forest is composed mainly of Pinus halepensis trees with an understory of typical Mediterranean shrubs species such as Quercus coccifera, Rosmarinus officinalis, Thymus vulgaris, Brachypodium retusum, etc. Soil is classified as a Typic Xerorthent (Soil Survey Staff, 2014) developed over marls. In February 2013, salvage logging (SL) treatment, with a complete extraction of the burned wood using heavy machinery, was applied to a part of the affected forest. Plots for monitoring the effects of SL were installed in this area and in a similar nearby control (C) area, where no SL treatment was done. The recovery of soil bacterial and fungal communities post-fire with and without tree removal was analysed by using Next-Generation sequencing and the abundance of functional genes, related to nitrogen cycling, in the soil was estimated using quantitative PCR (qPCR). We will present the methods used and the results of our study in this PICO presentation.

  7. [Responses of ecosystem carbon budget to increasing nitrogen deposition in differently degraded Leymus chinensis steppes in Inner Mongolia, China].

    Science.gov (United States)

    Qi, Yu-Chun; Peng, Qin; Dong, Yun-She; Xiao, Sheng-Sheng; Jia, Jun-Qiang; Quo, Shu-Fang; He, Yun-Long; Yan, Zhong-Qing; Wang, Li-Qin

    2015-02-01

    Based on a field manipulative nitrogen (N) addition experiment, the effects of atmospheric N deposition level change on the plant biomass and net primary productivity (NPP), soil respiration (Rs) and net ecosystem exchange (NEE) were investigated respectively in 2009 and 2010 in two differently degraded Leymus chinensis steppes in Inner Mongolia of China, and the difference in the response of NEE to equal amount of N addition [10 g x (M2 x a)(-1), MN] between the two steppes was also discussed. The results indicated that for the light degraded Leymus chinensis steppe (site A) , the average plant aboveground biomass (AGB) in MN treatment were 21.5% and 46.8% higher than those of CK in these two years. But for the moderate degraded Leymus chinensis steppe (site B), the N addition decreased the plant AGB and ANPP in 2009, while showed positive effects in 2010. N addition increased the belowground biomass (BGB) of the both sites and belowground NPP (BNPP) of site B in both years, but decreased the BNPP of site A in 2010. The increase of N input in the two steppes did not change the seasonal variation of Rs. The cumulative annual soil C emissions in MN treatment in site A showed an increase of about 14.6% and 25.7% of those in the CK respectively for these two years, while were decreased by about 10.4% and 11.3%, respectively in site B. The NEE of MN treatments, expressed by C, for the two steppes were 59.22 g x (m2 x a)(1) and 166.68 g x (m2 x a)(-1), as well as 83.27 g x (m2 x a)(-1) and 117.47 g x (m2 x a)(-1), respectively in these two years. The increments in NEE originated from N addition for these two years were 15.79 g x (M2 x a)(-1) and 82.94 g x (M2 x a)(-1) in site A and 74.54 g x (M2 x a)(-1) and 101.23 g x (M2 x a)(-1) in site B. The N input per unit could obtain greater C sink effect in the steppe with lower initial N level.

  8. Deficient expression of aldehyde dehydrogenase 1A1 is consistent with increased sensitivity of Gorlin syndrome patients to radiation carcinogenesis.

    Science.gov (United States)

    Wright, Aaron T; Magnaldo, Thierry; Sontag, Ryan L; Anderson, Lindsey N; Sadler, Natalie C; Piehowski, Paul D; Gache, Yannick; Weber, Thomas J

    2015-06-01

    Human phenotypes that are highly susceptible to radiation carcinogenesis have been identified. Sensitive phenotypes often display robust regulation of molecular features that modify biological response, which can facilitate identification of the pathways/networks that contribute to pathophysiological outcomes. Here we interrogate primary dermal fibroblasts isolated from Gorlin syndrome patients (GDFs), who display a pronounced inducible tumorigenic response to radiation, in comparison to normal human dermal fibroblasts (NHDFs). Our approach exploits newly developed thiol reactive probes to define changes in protein thiol profiles in live cell studies, which minimizes artifacts associated with cell lysis. Redox probes revealed deficient expression of an apparent 55 kDa protein thiol in GDFs from independent Gorlin syndrome patients, compared with NHDFs. Proteomics tentatively identified this protein as aldehyde dehydrogenase 1A1 (ALDH1A1), a key enzyme regulating retinoic acid synthesis, and ALDH1A1 protein deficiency in GDFs was confirmed by Western blot. A number of additional protein thiol differences in GDFs were identified, including radiation responsive annexin family members and lamin A/C. Collectively, candidates identified in our study have plausible implications for radiation health effects and cancer susceptibility.

  9. Mineral associated and aggregate-occluded soil carbon decreased with increasing nitrogen and residue input for three decades

    Science.gov (United States)

    Shahbaz, Muhammad; Kuzyakov, Yakov; Heitkamp, Felix

    2016-04-01

    Cropland soils may be a source or sink for atmospheric CO2. Therefore, effects of cropland management and fertilization on soil organic carbon (SOC) can be assessed best in long-term experiments. Generally, it is assumed that change in SOC is linearly related to C-input into the soil. However, recently it has been shown that residue incorporation resulted to only small extents in the increase of SOC levels. This gives rise to environmental concerns regarding the efficient use of crop residue. Such concerns are also applicable for the well designed and documented long-term experiment of Puch, Germany, in a silt-loam soil. The crop rotation is winter barley - winter wheat - silage maize. Five organic amendments were combined with N-fertiliser rates. The levels of organic amendments are unamended control (CON), straw was removed; farmyard manure (FYM), straw was removed; straw incorporation (STR); slurry application (SLU), straw was removed; and straw incorporation combined with slurry application (STSL). Three levels of mineral fertilizer application were selected: no nitrogen (N0); medium, 100 kg N ha-1year-1 (N2); and high, 200 kg N ha-1 year-1 (N4). These treatments resulted in a wide range of mean annual carbon input (1 - 5 t C ha-1 year-1). We hypothesize that the amount of soil carbon stored in different fractions will increase with C-input, but the effect will decrease in the order free light fraction (f-LF), occluded light fraction (o-LF) and heavy mineral-associated fraction (HF). Soil samples were fractionated by density using sodium polytungstate (1.6 g cm-3). Compared to the starting value SOC was lost in STR and CON and increased in SLU and STSL, whereas FYM showed no differences to initial carbon stocks. However, N additions resulted in only slightly increase in SOC contents with reference to C-input. The lower amount of o-LF carbon in CON and STR demonstrated the low ability of crop residue in comparison to animal manures to build up SOC contents

  10. Effects of Water Deficit and Increased Nitrogen Application in the Late Growth Stage on Physiological Characters of Anti-aging of Leaves in Different Hybrid Rice Varieties

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to explore the effects of water and fertilizer regulation on the function of leaves in the filling stage. [Method] Six hybrid rice vari- eties including prematurely aged types and non-prematurely aged ones were selected as experimental materials. Limiting water treatment (with soil water potential of about -25 kpa) and increasing nitrogen treatment (additional 10% of granular nitrogen fertiliz- er in addition to limiting water treatment) were applied after heading to analyse the rates of aging and physiological responses of anti-aging in different hybrid rice vari- eties under water deficit and increased nitrogen conditions taking regular water and fertilizer as control. [Result] The results showed that water deficit accelerated the leaf senescence, and prematurely aged types-'Zhongyou838', 'Tianyou998' and 'Long- ping601 '-were more markedly affected by water deficit, of which the rates of chloro- phyll degradation were 6%-8% higher compared to that in another three hybrids. In- creasing nitrogen treatment raised chlorophyll content and slowed down its degrada- tion. Water deficit caused the increase of abscisic acid (ABA) content to obviously varying degrees in leaves of six hybried rice varieties. Responses of ABA content in six hybried rice varieties to increased nitrogen fertilizer were not consistent. Except in 'Zhongyou838', ABA content in the other five hybrids had varying degrees of in- crease. The responses of the activity of antioxidant enzymes in different hybried rice varieties were inconsistent. In response to increased nitrogen fertilizer in combination with water deficit, the activity of each antioxidant enzyme changed differently. Water deficit enhanced the accumulation of malondialdehyde (MDA) in leaves of each hybrid rice. The correlation analysis showed that chlorophyll content was extremely signifi- cantly positively correlated to the resistance of each antioxidant enzyme; SOD activity in leaves also positively

  11. Root carbon inputs to the rhizosphere stimulate extracellular enzyme activity and increase nitrogen availability in temperate forest soils

    Science.gov (United States)

    Brzostek, E. R.; Phillips, R.; Dragoni, D.; Drake, J. E.; Finzi, A. C.

    2011-12-01

    The mobilization of nitrogen (N) from soil organic matter in temperate forest soils is controlled by the microbial production and activity of extracellular enzymes. The exudation of carbon (C) by tree roots into the rhizosphere may subsidize the microbial production of extracellular enzymes in the rhizosphere and increase the access of roots to N. The objective of this research was to investigate whether rates of root exudation and the resulting stimulation of extracellular enzyme activity in the rhizosphere (i.e., rhizosphere effect) differs between tree species that form associations with ectomycorrhizal (ECM) or arbuscular mycorrhizal (AM) fungi. This research was conducted at two temperate forest sites, the Harvard Forest (HF) in Central MA and the Morgan Monroe State Forest (MMSF) in Southern IN. At the HF, we measured rates of root exudation and the rhizosphere effects on enzyme activity, N cycling, and C mineralization in AM and ECM soils. At the MMSF, we recently girdled AM and ECM dominated plots to examine the impact of severing belowground C allocation on rhizosphere processes. At both sites, the rhizosphere effect on proteolytic, chitinolytic and ligninolytic enzyme activities was greater in ECM soils than in AM soils. In particular, higher rates of proteolytic enzyme activity increased the availability of amino acid-N in ECM rhizospheres relative to the bulk soils. Further, this stimulation of enzyme activity was directly correlated with higher rates of C mineralization in the rhizosphere than in the bulk soil. Although not significantly different between species, root exudation of C comprised 3-10% of annual gross primary production at the HF. At the MMSF, experimental girdling led to a larger decline in soil respiration and enzyme activity in ECM plots than in AM plots. In both ECM and AM soils, however, girdling resulted in equivalent rates of enzyme activity in rhizosphere and corresponding bulk soils. The results of this study contribute to the

  12. Iron deficiency is associated with increased levels of blood cadmium in the Korean general population: Analysis of 2008-2009 Korean National Health and Nutrition Examination Survey data

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung-Kook [Institute of Environmental and Occupational Medicine, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of); Kim, Yangho, E-mail: yanghokm@nuri.net [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Cheonha-Dong, Dong-Gu, Ulsan 682-060 (Korea, Republic of)

    2012-01-15

    Introduction: We present data from the Korean National Health and Nutrition Examination Survey 2008-2009 on the distribution of blood cadmium levels and their association with iron deficiency in a representative sample of the adult Korean population. Methods: Serum ferritin was categorized into three levels: low (serum ferritin <15.0 {mu}g/L), low normal (15.0-30.0 {mu}g/L for women and 15.0-50.0 for men), and normal ({>=}30.0 {mu}g/L for women and {>=}50.0 for men), and its association with blood cadmium level was assessed after adjustment for various demographic and lifestyle factors. Results: Geometric means of blood cadmium in the low serum ferritin group in women, men, and all participants were significantly higher than in the normal group. Additionally, multiple regression analysis after adjusting for various covariates showed that blood cadmium was significantly higher in the low-ferritin group in women, men, and all participants compared with the normal group. We also found an association between serum ferritin and blood cadmium among never-smoking participants. Discussion: We found, similar to other recent population-based studies, an association between iron deficiency and increased blood cadmium in men and women, independent of smoking status. The results of the present study show that iron deficiency is associated with increased levels of blood cadmium in the general population.

  13. Responses of loblolly pine, sweetgum and crab grass roots to localized increases in nitrogen in two watering regimes

    Science.gov (United States)

    Kim H. Ludovici; L.A. Morris

    1995-01-01

    Root responses to differences in availability of nitrogen and soil water were studied in loblolly pine (Pinus taeda L.) seedlings grown in monoculture and in competition with sweetgum (Liquidambar styraciflua L.) or crab grass (Digitaria spp.). Rhizotron cells were maintained at high soil water availability (...

  14. Ileal endogenous nitrogen recovery is increased and its amino acid pattern is altered in pigs fed quebracho extract

    NARCIS (Netherlands)

    Steendam, C.A.C.; Tamminga, S.; Boer, H.; de Jong, E.J.; Visser, G.H.; Verstegen, M.W.A.

    2004-01-01

    lleal endogenous nitrogen recovery (ENR) in pigs (9 +/- 0.6 kg body weight) was estimated simultaneously using the N-15-isotope dilution technique (N-15-IDT) and the peptide alimentation ultrafiltration (UF) method. Diets were cornstarch, enzyme-hydrolyzed casein with no (control) or high (4%) conte

  15. Cobalamin deficiency.

    Science.gov (United States)

    Herrmann, Wolfgang; Obeid, Rima

    2012-01-01

    Cobalamin (Cbl, vitamin B12) consists of a corrinoid structure with cobalt in the centre of the molecule. Neither humans nor animals are able to synthesize this vitamin. Foods of animal source are the only natural source of cobalamin in human diet. There are only two enzymatic reactions in mammalian cells that require cobalamin as cofactor. Methylcobolamin is a cofactor for methionine synthase. The enzyme methylmalonyl-CoA-mutase requires adenosylcobalamin as a cofactor. Therefore, serum concentrations of homocysteine (tHcy) and methylmalonic acid (MMA) will increase in cobalamin deficiency. The cobalamin absorption from diet is a complex process that involves different proteins: haptocorrin, intrinsic factor and transcobalamin (TC). Cobalamin that is bound to TC is called holotranscobalamin (holoTC) which is the metabolically active vitamin B12 fraction. HoloTC consists 6 and 20% of total cobalamin whereas 80% of total serum cobalamin is bound to another binding protein, haptocorrin. Cobalamin deficiency is common worldwide. Cobalamin malabsorption is common in elderly subjects which might explain low vitamin status. Subjects who ingest low amount of cobalamin like vegetarians develop vitamin deficiency. No single parameter can be used to diagnose cobalamin deficiency. Total serum cobalamin is neither sensitive nor it is specific for cobalamin deficiency. This might explain why many deficient subjects would be overlooked by utilizing total cobalamin as status marker. Concentration of holotranscobalamin (holoTC) in serum is an earlier marker that becomes decreased before total serum cobalamin. Concentrations of MMA and tHcy increase in blood of cobalamin deficient subjects. Despite limitations of these markers in patients with renal dysfunction, concentrations of MMA and tHcy are useful functional markers of cobalamin status. The combined use of holoTC and MMA assays may better indicate cobalamin status than either of them. Because Cbl deficiency is a risk factor

  16. Effect of an increase in brain serotonin on the osmoregulatory response to a hypo- or hyperosmotic load in Wistar and vasopressin-deficient Brattleboro rats.

    Science.gov (United States)

    Ivanova, L; Kochkaeva, L; Melidi, N

    2007-01-01

    Serotonin and its receptor agonists stimulate the release of arginine vasopressin (AVP) into peripheral blood under intraventricular injection. To test the hypothesis that brain serotonin can modulate the development of natural osmoregulatory responses, the effect of an increase in endogenous brain serotonin on the response to an intragastric hypo- or hyperosmotic loading was studied in Wistar and AVP-deficient Brattleboro rats. 5-Hydroxytryptophan (5-HTP), the rate-limiting serotonin biosynthesis precursor known to increase the brain level of serotonin, was injected intraperitoneally (5 mg/100 g body weight). The renal functional parameters (glomerular filtration rate [GFR], free water reabsorption, and urine flow rate) were monitored during the 4 h after intragastric infusion of water or a 2% NaCl solution (5% of body weight). Plasma AVP was measured by radioimmunoassay. In Wistar rats, intraperitoneal injection of 5-HTP at the same time as water loading prevented the development of the renal diuretic response: there was no increase in urine flow rate and GFR, and free water reabsorption remained at the high level. In AVP-deficient Brattleboro rats, unlike Wistar rats, 5-HTP treatment was without effect on the renal function parameters. In Wistar rats, injection of 5-HTP at the peak of water diuresis produced an abrogation of the diuretic response to water loading due to the increase in free water reabsorption. Plasma AVP increased from 1.2 +/- 0.4 to 4.2 +/- 1.6 pg/ml (n = 8 in each group, p HTP revealed no additive effect on plasma AVP and on free water reabsorption. We conclude that the 5-HTP-caused increase in brain serotonin contributed significantly to the dynamics of changes in the osmoregulatory response to the hypo-osmotic challenge due to stimulation of AVP secretion. 5-HTP had no additive effect on the osmoregulatory response to hyperosmotic loading. Peripherally injected 5-HTP had no effect on the renal function, being absent in AVP-deficient

  17. Effect of nitrogen nutrition on the response of tobacco to ozone in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Leone, I.A.; Brennan, E.; Daines, R.H.

    1966-04-01

    With Nicotiana rustica L., a noncommercial tobacco, plants receiving an optimum nitrogen supply were found to be more susceptible to ozone injury than those receiving deficient or luxury supplies. Furthermore, it was found on analyses of the third oldest tobacco leaf that, while these optimum plants showed little or no increase in respiration as a result of ozone in concentrations too low to produce visible injury, plants grown with deficient or excess nitrogen showed a significant increase in respiration under these same conditions. The increase in respiration was accompanied by a comparable and equally significant decrease in carbohydrate content in the latter plants which was not apparent in plants at the optimum nitrogen supply, as well as an increase in total nitrogen, protein-nitrogen, and amino-acid nitrogen. It is suggested that the carbohydrate reserve built up in plants grown with deficient nitrogen nutrition serves as protection against the oxidative potential of ozone. Likewise, a decrease in carbohydrate content below that of optimum plants provides protection in plants grown with an overabundance of nitrogen fertilization, though possibly by a more complex mechanism. 20 references, 7 figures, 2 tables.

  18. Overexpression of AtFRO6 in transgenic tobacco enhances ferric chelate reductase activity in leaves and increases tolerance to iron-deficiency chlorosis.

    Science.gov (United States)

    Li, Li-Ya; Cai, Qiu-Yi; Yu, Dian-Si; Guo, Chang-Hong

    2011-08-01

    The Arabidopsis gene FRO6(AtFRO6) encodes ferric chelate reductase and highly expressed in green tissues of plants. We have expressed the gene AtFRO6 under the control of a 35S promoter in transgenic tobacco plants. High-level expression of AtFRO6 in transgenic plants was confirmed by northern blot analysis. Ferric reductase activity in leaves of transgenic plants grown under iron-sufficient or iron-deficient conditions is 2.13 and 1.26 fold higher than in control plants respectively. The enhanced ferric reductase activity led to increased concentrations of ferrous iron and chlorophyll, and reduced the iron deficiency chlorosis in the transgenic plants, compared to the control plants. In roots, the concentration of ferrous iron and ferric reductase activity were not significantly different in the transgenic plants compared to the control plants. These results suggest that FRO6 functions as a ferric chelate reductase for iron uptake by leaf cells, and overexpression of AtFRO6 in transgenic plants can reduce iron deficiency chlorosis.

  19. Molecular Biology of Nitrogen Fixation

    Science.gov (United States)

    Shanmugam, K. T.; Valentine, Raymond C.

    1975-01-01

    Reports that as a result of our increasing knowledge of the molecular biology of nitrogen fixation it might eventually be possible to increase the biological production of nitrogenous fertilizer from atmospheric nitrogen. (GS)

  20. Increased duodenal DMT-1 expression and unchanged HFE mRNA levels in HFE-associated hereditary hemochromatosis and iron deficiency.

    Science.gov (United States)

    Byrnes, V; Barrett, S; Ryan, E; Kelleher, T; O'Keane, C; Coughlan, B; Crowe, J

    2002-01-01

    HFE-associated hereditary hemochromatosis is characterized by imbalances of iron homeostasis and alterations in intestinal iron absorption. The identification of the HFE gene and the apical iron transporter divalent metal transporter-1, DMT-1, provide a direct method to address the mechanisms of iron overload in this disease. The aim of this study was to evaluate the regulation of duodenal HFE and DMT-1 gene expression in HFE-associated hereditary hemochromatosis. Small bowel biopsies and serum iron indices were obtained from a total of 33 patients. The study population comprised 13 patients with hereditary hemochromatosis (C282Y homozygous), 10 patients with iron deficiency anemia, and 10 apparently healthy controls, all of whom were genotyped for the two common mutations in the HFE gene (C282Y and H63D). Total RNA was isolated from tissue and amplified via RT-PCR for HFE, DMT-1, and the internal control GAPDH. DMT-1 protein expression was additionally assessed by immunohistochemistry. Levels of HFE mRNA did not differ significantly between patient groups (P = 0.09), specifically between C282Y homozygotes and iron deficiency anemic patients, when compared to controls (P = 0.09, P = 0.9, respectively). In contrast, DMT-1 mRNA levels were at least twofold greater in patients with hereditary hemochromatosis and iron deficiency anemia when compared to controls (P = 0.02, P = 0.01, respectively). Heightened DMT-1 protein expression correlated with mRNA levels in all patients. Loss of HFE function in hereditary hemochromatosis is not derived from inhibition of its gene expression. DMT-1 expression in C282Y homozygote subjects is consistent with the hypothesis of a "paradoxical" duodenal iron deficiency in hereditary hemochromatosis. The observed twofold upregulation of the DMT-1 is consistent with the slow but steady increase in body iron stores observed in those presenting with clinical features of hereditary hemochromatosis.

  1. An Increase in Consuming Adequately Iodized Salt May Not Be Enough to Rectify Iodine Deficiency in Pregnancy in an Iodine-Sufficient Area of China

    Science.gov (United States)

    Wang, Zhifang; Zhu, Wenming; Mo, Zhe; Wang, Yuanyang; Mao, Guangming; Wang, Xiaofeng; Lou, Xiaoming

    2017-01-01

    Universal salt iodization (USI) has been implemented for two decades in China. It is crucial to periodically monitor iodine status in the most vulnerable population, such as pregnant women. A cross-sectional study was carried out in an evidence-proved iodine-sufficient province to evaluate iodine intake in pregnancy. According to the WHO/UNICEF/ICCIDD recommendation criteria of adequate iodine intake in pregnancy (150–249 µg/L), the median urinary iodine concentration (UIC) of the total 8159 recruited pregnant women was 147.5 µg/L, which indicated pregnant women had iodine deficiency at the province level. Overall, 51.0% of the total study participants had iodine deficiency with a UIC < 150 µg/L and only 32.9% of them had adequate iodine. Participants living in coastal areas had iodine deficiency with a median UIC of 130.1 µg/L, while those in inland areas had marginally adequate iodine intake with a median UIC of 158.1 µg/L (p < 0.001). Among the total study participants, 450 pregnant women consuming non-iodized salt had mild-moderate iodine deficiency with a median UIC of 99.6 µg/L; 7363 pregnant women consuming adequately iodized salt had a lightly statistically higher median UIC of 151.9 µg/L, compared with the recommended adequate level by the WHO/UNICEF/ICCIDD (p < 0.001). Consuming adequately iodized salt seemed to lightly increase the median UIC level, but it may not be enough to correct iodine nutrition status to an optimum level as recommended by the WHO/UNICEF/ICCIDD. We therefore suggest that, besides strengthening USI policy, additional interventive measure may be needed to improve iodine intake in pregnancy. PMID:28230748

  2. Acidification and Nitrogen Eutrophication of Austrian Forest Soils

    Directory of Open Access Journals (Sweden)

    Robert Jandl

    2012-01-01

    Full Text Available We evaluated the effect of acidic deposition and nitrogen on Austrian forests soils. Until thirty years ago air pollution had led to soil acidification, and concerns on the future productivity of forests were raised. Elevated rates of nitrogen deposition were believed to cause nitrate leaching and imbalanced forest nutrition. We used data from a soil monitoring network to evaluate the trends and current status of the pH and the C : N ratio of Austrian forest soils. Deposition measurements and nitrogen contents of Norway spruce needles and mosses were used to assess the nitrogen supply. The pH values of soils have increased because of decreasing proton depositions caused by reduction of emissions. The C : N ratio of Austrian forest soils is widening. Despite high nitrogen deposition rates the increase in forest stand density and productivity has increased the nitrogen demand. The Austrian Bioindicator Grid shows that forest ecosystems are still deficient in nitrogen. Soils retain nitrogen efficiently, and nitrate leaching into the groundwater is presently not a large-scale problem. The decline of soil acidity and the deposition of nitrogen together with climate change effects will further increase the productivity of the forests until a limiting factor such as water scarcity becomes effective.

  3. Fasting-induced increases in aquaporin 7 and adipose triglyceride lipase mRNA expression in adipose tissue are attenuated by peroxisome proliferator-activated receptor alpha deficiency.

    Science.gov (United States)

    Walker, C G; Holness, M J; Gibbons, G F; Sugden, M C

    2007-07-01

    To investigate the impact of peroxisome proliferator-activated receptor alpha deficiency on gene expression of adipose triglyceride lipase and the glycerol transporter aquaglyceroporin 7 in white adipose tissue in the fed and fasted states in relation to glycerol release by isolated adipocytes. Studies using wild-type and peroxisome proliferator-activated receptor alpha null mice. Hormone and metabolite concentrations, real-time polymerase chain reaction (PCR), basal and stimulated adipocyte lipolysis, estimated by glycerol release. Peroxisome proliferator-activated receptor alpha deficiency blocked the increase in aquaglyceroporin 7 transcript level and attenuated the increase in adipose triglyceride lipase transcript level in white adipose tissue elicited by fasting. Fasting glycerol levels were lower in peroxisome proliferator-activated receptor alpha null than wild-type mice, despite increased mobilization of adipocyte fat reserves in vivo as indicated by reduced adipose tissue masses (three distinct depots) and a significantly lower epididymal adipocyte diameter. Basal net glycerol release was unchanged but beta-adrenergic-stimulated net glycerol release was higher with isolated adipocytes from fasted peroxisome proliferator-activated receptor alpha null mice compared with those of fasted wild-type mice. Peroxisome proliferator-activated receptor alpha deficiency prevents effects of fasting to increase adipocyte aquaglyceroporin 7 gene expression, and influences the regulation of inter-tissue glycerol flux after fasting via lowered adipocyte aquaglyceroporin 7 expression. Lowered gene expression of adipose triglyceride lipase and aquaglyceroporin 7 in peroxisome proliferator-activated receptor alpha null mice is not limiting for adipose triglyceride breakdown in vivo during fasting.

  4. Both immanently high active iron contents and increased root ferrous uptake in response to low iron stress contribute to the iron deficiency tolerance in Malus xiaojinensis.

    Science.gov (United States)

    Zha, Qian; Wang, Yi; Zhang, Xin-Zhong; Han, Zhen-Hai

    2014-01-01

    To better understand the mechanism of low-iron stress tolerance in Malus xiaojinensis, the differences in physiological parameters and gene expression between an iron deficiency-sensitive species, Malus baccata, and an iron deficiency-tolerant species, M. xiaojinensis were investigated under low-iron (4 μM Fe) conditions. Under iron sufficient conditions, the expressions of iron uptake- and transport-related genes, i.e. FIT1, IRT1, CS1, FRD3 and NRMAP1, and the immanent leaf and root active iron contents were higher in M. xiaojinensis than those in M. baccata. However, on the first three days of low iron stress, the rhizospheric pH decreased and the root ferric chelate reductase (FCR) activity and the expression of ferrous uptake- and iron transport-related genes in the roots increased significantly only in M. xiaojinensis. Leaf chlorosis occurred on the 3rd and the 9th day after low-iron treatment in M. baccata and M. xiaojinensis, respectively. The expression of iron relocalization-related genes, such as NAS1, FRD3 and NRMAP3, increased after the 5th or 6th day of low iron stress in leaves of M. xiaojinensis, whereas the expression of NAS1, FRD3 and NRMAP3 in the leaves of M. baccata increased immediately after the onset of low iron treatment. Conclusively, the relative high active iron contents caused by the immanently active root ferrous uptake and the increased root ferrous uptake in response to low iron stress were the dominant mechanisms for the tolerance to iron deficiency in M. xiaojinensis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. Pannexin-1 Deficient Mice Have an Increased Susceptibility for Atrial Fibrillation and Show a QT-Prolongation Phenotype

    Directory of Open Access Journals (Sweden)

    Stella Petric

    2016-02-01

    Full Text Available Background/Aims: Pannexin-1 (Panx1 is an ATP release channel that is ubiquitously expressed and coupled to several ligand-gated receptors. In isolated cardiac myocytes, Panx1 forms large conductance channels that can be activated by Ca2+ release from the sarcoplasmic reticulum. Here we characterized the electrophysiological function of these channels in the heart in vivo, taking recourse to mice with Panx1 ablation. Methods: Cardiac phenotyping of Panx1 knock-out mice (Panx1-/- was performed by employing a molecular, cellular and functional approach, including echocardiography, surface and telemetric ECG recordings with QT analysis, physical stress testing and quantification of heart rate variability. In addition, an in vivo electrophysiological study entailed programmed electrical stimulation using an intracardiac octapolar catheter. Results: Panx1 deficiency results in a higher incidence of AV-block, delayed ventricular depolarisation, significant prolongation of QT- and rate corrected QT-interval and a higher incidence of atrial fibrillation after intraatrial burst stimulation. Conclusion: Panx1 seems to play an important role in murine cardiac electrophysiology and warrants further consideration in the context of hereditary forms of atrial fibrillation.

  6. Vitamin D3 deficiency increases DNA damage and modify the expression of genes associated with hypertension in normotensive and hypertensive rats

    Directory of Open Access Journals (Sweden)

    Carla Silva Machado

    2015-05-01

    Full Text Available Vitamin D3 is a lipophilic micronutrient obtained from the diet (salmon, sardines, mackerel and cod liver oil or by the conversion of 7-dehydrocholesterol on skin after exposure to UVB radiation. This vitamin participates in several cellular processes, contributes to the maintenance of calcium concentrations, acts on phosphorus absorption, and is also related to the development and progression of chronic diseases. In hypertension, it is known that vitamin D3 act on renin-angiotensin-aldosterone system, regulates the gene expression and can induce or attenuate oxidative DNA damage. Vitamin D3 deficiency is present in 30-50% of human population (Pilz et al., 2009, and has been associated with increase of chromosomal instability and DNA damage (Nair-Shalliker; Armstrong; Fenech, 2012. Since experimental and clinical studies have suggested a relationship between vitamin D3 and blood pressure, the aim of this study was to evaluate whether vitamin D3 deficiency or supplementation lead to an increase or decrease in DNA damage, regulates the expression of genes associated with hypertension and changes the systolic blood pressure. Spontaneously hypertensive rats (SHR, used as a model of human essential hypertension, and their normotensive controls (Wistar Kyoto – WKY were fed a control diet (vitamin D3 at 1.000 UI/kg, a deficient diet (vitamin D3 at 0 UI/kg or a supplemented diet (vitamin D3 at 10.000 UI/kg for 12 weeks. DNA damage was assessed by comet assay in cardiac muscle tissue and blood tissue, following the methodology proposed by Singh et al. (1988 and Tice et al. (2000; gene expression of 84 genes was assessed by RT2ProfilerTM PCR Array in cardiac muscle tissue; and systolic blood pressure was measured weekly by a noninvasive method using tail plethysmography. In SHR and WKY rats, vitamin D3 deficiency increased DNA damage in the blood tissue and did not change the DNA damage in cardiac muscle tissue; vitamin D3 supplementation maintained the

  7. Randomized Control Trial Assessing Impact of Increased Sunlight Exposure versus Vitamin D Supplementation on Lipid Profile in Indian Vitamin D Deficient Men.

    Science.gov (United States)

    Patwardhan, Vivek G; Mughal, Zulf M; Padidela, Raja; Chiplonkar, Shashi A; Khadilkar, Vaman V; Khadilkar, Anuradha V

    2017-01-01

    Despite abundance of sunshine in India, Vitamin D deficiency is common and therefore there is an increasing trend toward taking Vitamin D supplements either as prescription medicine or as a nutritional supplement. Studies have suggested that duration of sun exposure may influence serum lipid profile. To study the effect of increased sunlight exposure versus Vitamin D supplementation on Vitamin D status and lipid profile in individuals with Vitamin D deficiency (25-hydroxyvitamin-D [25OHD] 50 nmol/L, n = 50) and intervention (sunlight exposure group" (n = 50, received at least 20 min sunlight exposure to forearms and face between 11 a.m. and 3 p.m. over and above their current exposure) or "cholecalciferol supplement group" (n = 50, received oral cholecalciferol 1000 IU/day). Significant increase in 25OHD concentrations was seen in both intervention groups (P sunlight exposure (P sunlight exposure significantly reduced TC, LDL-C, and HDL-C concentrations, and cholecalciferol supplementation increased TC and HDL-C concentrations.

  8. Deletion of Galgt2 (B4Galnt2) Reduces Muscle Growth in Response to Acute Injury and Increases Muscle Inflammation and Pathology in Dystrophin-Deficient Mice

    Science.gov (United States)

    Xu, Rui; Singhal, Neha; Serinagaoglu, Yelda; Chandrasekharan, Kumaran; Joshi, Mandar; Bauer, John A.; Janssen, Paulus M.L.; Martin, Paul T.

    2016-01-01

    Transgenic overexpression of Galgt2 (official name B4Galnt2) in skeletal muscle stimulates the glycosylation of α dystroglycan (αDG) and the up-regulation of laminin α2 and dystrophin surrogates known to inhibit muscle pathology in mouse models of congenital muscular dystrophy 1A and Duchenne muscular dystrophy. Skeletal muscle Galgt2 gene expression is also normally increased in the mdx mouse model of Duchenne muscular dystrophy compared with the wild-type mice. To assess whether this increased endogenous Galgt2 expression could affect disease, we quantified muscular dystrophy measures in mdx mice deleted for Galgt2 (Galgt2−/−mdx). Galgt2−/− mdx mice had increased heart and skeletal muscle pathology and inflammation, and also worsened cardiac function, relative to age-matched mdx mice. Deletion of Galgt2 in wild-type mice also slowed skeletal muscle growth in response to acute muscle injury. In each instance where Galgt2 expression was elevated (developing muscle, regenerating muscle, and dystrophic muscle), Galgt2-dependent glycosylation of αDG was also increased. Overexpression of Galgt2 failed to inhibit skeletal muscle pathology in dystroglycan-deficient muscles, in contrast to previous studies in dystrophin-deficient mdx muscles. This study demonstrates that Galgt2 gene expression and glycosylation of αDG are dynamically regulated in muscle and that endogenous Galgt2 gene expression can ameliorate the extent of muscle pathology, inflammation, and dysfunction in mdx mice. PMID:26435413

  9. Increases in nitrogen uptake rather than nitrogen-use efficiency support higher rates of temperate forest productivity under elevated CO2

    NARCIS (Netherlands)

    Finzi, A.C.; Norby, R.J.; Calfapietra, C.; Gallet-Budynek, A.; Gielen, B.; Holmes, W.E.; Hoosbeek, M.R.; Iversen, C.M.; Jackson, R.B.; Kubiske, M.E.; Ledford, J.; Liberloo, M.; Oren, R.; Polle, A.; Pritchard, S.; Zak, D.R.; Schlesinger, W.H.; Ceulemans, R.

    2007-01-01

    Forest ecosystems are important sinks for rising concentrations of atmospheric CO2. In previous research, we showed that net primary production (NPP) increased by 23 ± 2% when four experimental forests were grown under atmospheric concentrations of CO2 predicted for the latter half of this century.

  10. Over-expression of a tobacco nitrate reductase gene in wheat (Triticum aestivum L. increases seed protein content and weight without augmenting nitrogen supplying.

    Directory of Open Access Journals (Sweden)

    Xiao-Qiang Zhao

    Full Text Available Heavy nitrogen (N application to gain higher yield of wheat (Triticum aestivum L. resulted in increased production cost and environment pollution. How to diminish the N supply without losing yield and/or quality remains a challenge. To meet the challenge, we integrated and expressed a tobacco nitrate reductase gene (NR in transgenic wheat. The 35S-NR gene was transferred into two winter cultivars, "Nongda146" and "Jimai6358", by Agrobacterium-mediation. Over-expression of the transgene remarkably enhanced T1 foliar NR activity and significantly augmented T2 seed protein content and 1000-grain weight in 63.8% and 68.1% of T1 offspring (total 67 individuals analyzed, respectively. Our results suggest that constitutive expression of foreign nitrate reductase gene(s in wheat might improve nitrogen use efficiency and thus make it possible to increase seed protein content and weight without augmenting N supplying.

  11. Altered inflammatory response and increased neurodegeneration in metallothionein I+II deficient mice during experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Penkowa, M; Espejo, C; Martínez-Cáceres, E M;

    2001-01-01

    was significantly decreased. In addition, the expression of the proinflammatory cytokines interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha elicited by EAE was further increased in the MTKO mice, and oxidative stress and apoptosis were also significantly increased in MTKO mice compared to normal...

  12. Influence of abscisic acid on growth, biomass and lipid yield of Scenedesmus quadricauda under nitrogen starved condition.

    Science.gov (United States)

    Sulochana, Sujitha Balakrishnan; Arumugam, Muthu

    2016-08-01

    Scenedesmus quadricauda, accumulated more lipid but with a drastic reduction in biomass yield during nitrogen starvation. Abscisic acid (ABA) being a stress responsible hormone, its effect on growth and biomass with sustainable lipid yield during nitrogen depletion was studied. The result revealed that the ABA level shoots up at 24h (27.21pmol/L) during the onset of nitrogen starvation followed by a sharp decline. The external supplemented ABA showed a positive effect on growth pattern (38×10(6)cells/ml) at a lower concentration. The dry biomass yield is also increasing up to 2.1 fold compared to nitrogen deficient S. quadricauda. The lipid content sustains in 1 and 2μM concentration of ABA under nitrogen-deficient condition. The fatty acid composition of ABA treated S. quadricauda cultures with respect to nitrogen-starved cells showed 11.17% increment in saturated fatty acid content, the desired lipid composition for biofuel application.

  13. Increased outer arm and core fucose residues on the N-glycans of mutated alpha-1 antitrypsin protein from alpha-1 antitrypsin deficient individuals.

    Science.gov (United States)

    McCarthy, Cormac; Saldova, Radka; O'Brien, M Emmet; Bergin, David A; Carroll, Tomás P; Keenan, Joanne; Meleady, Paula; Henry, Michael; Clynes, Martin; Rudd, Pauline M; Reeves, Emer P; McElvaney, Noel G

    2014-02-01

    Alpha-1 antitrypsin (AAT) is the major physiological inhibitor of a range of serine proteases, and in the lung, it maintains a protease-antiprotease balance. AAT deficiency (AATD) is an autosomal co-dominant condition with the Z mutation being the most common cause. Individuals homozygous for Z (PiZZ) have low levels of circulating mutant Z-AAT protein leading to premature emphysematous lung disease. Extensive glycoanalysis has been performed on normal AAT (M-AAT) from healthy individuals and the importance of glycosylation in affecting the immune modulatory roles of AAT is documented. However, no glycoanalysis has been carried out on Z-AAT from deficient individuals to date. In this study, we investigate whether the glycans present on Z-AAT differ to those found on M-AAT from healthy controls. Plasma AAT was purified from 10 individuals: 5 AATD donors with the PiZZ phenotype and 5 PiMM healthy controls. Glycoanalysis was performed employing N-glycan release, exoglycosidase digestion and UPLC analysis. No difference in branched glycans was identified between AATD and healthy controls. However, a significant increase in both outer arm (α1-3) (p = 0.04) and core (α1-6) fucosylated glycans (p < 0.0001) was found on Z-AAT compared to M-AAT. This study has identified increased fucosylation on N-glycans of Z-AAT indicative of ongoing inflammation in AATD individuals with implications for early therapeutic intervention.

  14. γ-Glutamyltransferases (GGT) in Colletotrichum graminicola: mRNA and enzyme activity, and evidence that CgGGT1 allows glutathione utilization during nitrogen deficiency.

    Science.gov (United States)

    Bello, Marco H; Morin, Dexter; Epstein, Lynn

    2013-02-01

    Gamma-glutamyltransferase (GGT, EC 2.3.2.2) cleaves the γ-glutamyl linkage in glutathione (GSH). Three GGTs in the hemibiotrophic plant pathogen Colletotrichum graminicola were identified in silico. GGT mRNA expression was monitored by quantitative reverse-transcriptase PCR. Expression of all three genes was detected in planta during the biotrophic and necrotrophic stages of infection. Of the three GGTs, CgGGT1 mRNA (from gene GLRG_09590) was the most highly expressed. All three GGT mRNAs were up-regulated in wild type nitrogen-starved germlings in comparison to non-starved germlings. CgGGT1 was insertionally mutagenized in C. graminicola, complemented with the wild type form of the gene, and over-expressed. Enzyme assays of two independent CgGGT1 knockouts and the wild type indicated that CgGGT1 is the major GGT and accounts for 86% and 68% of total GGT activity in conidia and mycelia, respectively. The over-expressing strain had 8-fold and 3-fold more enzyme activity in conidia and mycelia, respectively, than the wild type. In an analysis of the GGT knockout, complemented and over-expressing strains, GGT1 transcript levels are highly correlated (r=0.95) with levels of total GGT enzyme activity. CgGGT1 and CgGGT2 genes in strains that had ectopic copies of CgGGT1 were not up-regulated by nitrogen-starvation, in contrast to the wild type. Deletion or over-expression of CgGGT1 had no effect on mRNA expression of CgGGT2 and CgGGT3. In broth in which 3 and 6mM glutathione (GSH) was the nitrogen source, the CgGGT1 over-expressing strain produced significantly (P<0.0001) more biomass than the wild type and complemented strains, whereas the CgGGT1Δ strains produced significantly (P<0.0001) less biomass than the wild type strain. This suggests that CgGGT1 is involved in utilizing GSH as a nitrogen source. However, deletion and over-expression of CgGGT1 had no effect on either virulence in wounded corn leaf sheaths or GSH levels in conidia and mycelia. Thus, the

  15. Long-term combined chemical and manure fertilizations increase soil organic carbon and total nitrogen in aggregate fractions at three typical cropland soils in China.

    Science.gov (United States)

    He, Y T; Zhang, W J; Xu, M G; Tong, X G; Sun, F X; Wang, J Z; Huang, S M; Zhu, P; He, X H

    2015-11-01

    Soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC) and nitrogen (MBN) are important factors of soil fertility. However, effects of the combined chemical fertilizer and organic manure or straw on these factors and their relationships are less addressed under long-term fertilizations. This study addressed changes in SOC, TN, MBC and MBN at 0-20 cm soil depth under three 17 years (September 1990-September 2007) long-term fertilization croplands along a heat and water gradient in China. Four soil physical fractions (coarse free and fine free particulate organic C, cfPOC and ffPOC; intra-microaggregate POC, iPOC; and mineral associated organic C, MOC) were examined under five fertilizations: unfertilized control, chemical nitrogen (N), phosphorus (P) and potassium (K) (NPK), NPK plus straw (NPKS, hereafter straw return), and NPK plus manure (NPKM and 1.5NPKM, hereafter manure). Compared with Control, manure significantly increased all tested parameters. SOC and TN in fractions distributed as MOC > iPOC > cfPOC > ffPOC with the highest increase in cfPOC (329.3%) and cfPTN (431.1%), and the lowest in MOC (40.8%) and MTN (45.4%) under manure. SOC significantly positively correlated with MBC, cfPOC, ffPOC, iPOC and MOC (R(2) = 0.51-0.84, P fertilization for improving soil fertility while straw return should take into account climate factors in Chinese croplands.

  16. Lactobacillus-Deficient Cervicovaginal Bacterial Communities Are Associated with Increased HIV Acquisition in Young South African Women.

    Science.gov (United States)

    Gosmann, Christina; Anahtar, Melis N; Handley, Scott A; Farcasanu, Mara; Abu-Ali, Galeb; Bowman, Brittany A; Padavattan, Nikita; Desai, Chandni; Droit, Lindsay; Moodley, Amber; Dong, Mary; Chen, Yuezhou; Ismail, Nasreen; Ndung'u, Thumbi; Ghebremichael, Musie S; Wesemann, Duane R; Mitchell, Caroline; Dong, Krista L; Huttenhower, Curtis; Walker, Bruce D; Virgin, Herbert W; Kwon, Douglas S

    2017-01-17

    Elevated inflammation in the female genital tract is associated with increased HIV risk. Cervicovaginal bacteria modulate genital inflammation; however, their role in HIV susceptibility has not been elucidated. In a prospective cohort of young, healthy South African women, we found that individuals with diverse genital bacterial communities dominated by anaerobes other than Gardnerella were at over 4-fold higher risk of acquiring HIV and had increased numbers of activated mucosal CD4(+) T cells compared to those with Lactobacillus crispatus-dominant communities. We identified specific bacterial taxa linked with reduced (L. crispatus) or elevated (Prevotella, Sneathia, and other anaerobes) inflammation and HIV infection and found that high-risk bacteria increased numbers of activated genital CD4(+) T cells in a murine model. Our results suggest that highly prevalent genital bacteria increase HIV risk by inducing mucosal HIV target cells. These findings might be leveraged to reduce HIV acquisition in women living in sub-Saharan Africa.

  17. Sensory defects in Necdin deficient mice result from a loss of sensory neurons correlated within an increase of developmental programmed cell death

    Directory of Open Access Journals (Sweden)

    Fernandez Pierre-Alain

    2006-11-01

    Full Text Available Abstract Background The human NECDIN gene is involved in a neurodevelopmental disorder, Prader-Willi syndrome (PWS. Previously we reported a mouse Necdin knock-out model with similar defects to PWS patients. Despite the putative roles attributed to Necdin, mainly from in vitro studies, its in vivo function remains unclear. In this study, we investigate sensory-motor behaviour in Necdin deficient mice. We reveal cellular defects and analyse their cause. Results We report sensory differences in Necdin deficient mice compared to wild type animals. These differences led us to investigate sensory neuron development in Necdin deficient mouse embryos. First, we describe the expression pattern of Necdin in developing DRGs and report a reduction of one-third in specified sensory neurons in dorsal roots ganglia and show that this neuronal loss is achieved by E13.5, when DRGs sensory neurons are specified. In parallel, we observed an increase of 41% in neuronal apoptosis during the wave of naturally occurring cell death at E12.5. Since it is assumed that Necdin is a P75NTR interactor, we looked at the P75NTR-expressing cell population in Necdin knock-out embryos. Unexpectedly, Necdin loss of function has no effect on p75NTR expressing neurons suggesting no direct genetic interaction between Necdin and P75NTR in this context. Although we exclude a role of Necdin in axonal outgrowth from spinal sensory neurons in early developmental stages; such a role could occur later in neuronal differentiation. Finally we also exclude an anti-proliferative role of Necdin in developing sensory neurons. Conclusion Overall, our data show clearly that, in early development of the nervous system, Necdin is an anti-apoptotic or survival factor.

  18. The winter-red-leaf syndrome in Pistacia lentiscus: evidence that the anthocyanic phenotype suffers from nitrogen deficiency, low carboxylation efficiency and high risk of photoinhibition.

    Science.gov (United States)

    Nikiforou, Constantinos; Nikolopoulos, Dimosthenis; Manetas, Yiannis

    2011-12-15

    Recent evidence indicates that winter-red leaf phenotypes in the mastic tree (Pistacia lentiscus) are more vulnerable to chronic photoinhibition during the cold season relative to winter-green phenotypes occurring in the same high light environment. This was judged by limitations in the maximum quantum yield of photosystem II (PSII), found in previous studies. In this investigation, we asked whether corresponding limitations in leaf gas exchange and carboxylation reactions could also be manifested. During the cold ("red") season, net CO₂ assimilation rates (A) and stomatal conductances (g(s)) in the red phenotype were considerably lower than in the green phenotype, while leaf internal CO₂ concentration (Ci) was higher. The differences were abolished in the "green" period of the year, the dry summer included. Analysis of A versus Ci curves indicated that CO₂ assimilation during winter in the red phenotype was limited by Rubisco content and/or activity rather than stomatal conductance. Leaf nitrogen levels in the red phenotype were considerably lower during the red-leaf period. Consequently, we suggest that the inherently low leaf nitrogen levels are linked to the low net photosynthetic rates of the red plants through a decrease in Rubisco content. Accordingly, the reduced capacity of the carboxylation reactions to act as photosynthetic electron sinks may explain the corresponding loss of PSII photon trapping efficiency, which cannot be fully alleviated by the screening effect of the accumulated anthocyanins.

  19. Raffinate waste as a nitrogen replacement to increase the sustainable use of marine microalgae for biofuel production

    Science.gov (United States)

    Swink, C.; Palenik, B.

    2016-02-01

    High lipid content and the ability to be grown on areal non-agricultural land make microalgae one of the few viable candidates for long-term sustainable biofuel production. However, many challenges arise when attempting to scale-up production of algae biofuels at a successful industrial level. A series of growth experiments and toxicity tests were conducted to test the adaptability of 10 different strains of microalgae to grow in cultures containing two types of "raffinate" waste product as a nitrogen replacement. The results of these tests revealed that all strains of microalgae could successfully grow in cultures containing raffinate produced by means of hydrothermal liquefaction, even in bag culture, but not in cultures containing raffinate produced by a lipid trap extraction method. The application of these results is a method of reducing the costs of producing biofuel from marine and freshwater microalgae by creating a more self-sustaining recycling of nutrients from high temperature liquefaction waste.

  20. [The method of tonifying kidneys and activating blood circulation increases testosterone secretion index in late-onset hypogonadism males with kidney deficiency].

    Science.gov (United States)

    Zhou, Shao-Hu; Weng, Zhi-Wei; Li, Tang-Lin

    2013-07-01

    To investigate the effect of the method of tonifying the kidney and activating blood circulation on the testosterone secretion index (TSI) in late-onset hypogonadism (LOH) male patients with kidney deficiency and its possible mechanisms. We screened 60 LOH male patients with kidney deficiency based on the scores on Partial Androgen Deficiency in Aging Males (PADAM), the levels of serum total testosterone (TT) and luteinizing hormone (LH), and TSI (TT/LH). We randomly divided the patients into a Nan Geng Ning (NGN) group (n = 40, aged 55.02 +/- 11.37 years) and a control group (n = 20, aged 54.56 +/- 12.12 years) to be treated orally with NGN decoction and testosterone undecanoate capsules, respectively, both for 12 consecutive weeks. We obtained the scores on psychological status, physical status and sexual function and observed the changes in serum TT, LH and TSI after 4, 8 and 12 weeks of treatment. Compared with the baseline, both the NGN and control groups showed a significant reduction after 12 weeks of medication in the LH level ([5.32 +/- 2.08] vs [4.89 +/- 1.46] IU/L and [5.36 +/- 2.07] vs [4.81 +/- 1.75] IU/L, P 1.5, P TSI ([2.14 +/- 0.65] vs [2.99 +/- 0.72] nmol/IU and ([2.05 +/- 0.73] vs [3.11 +/- 0.65] nmol/IU, P 0.05), TT ([14.55 +/- 0.75] vs [14.74 +/- 0.83] nmol/L, P > 0.05), TSI ([2.99 +/- 0.72] vs [3.11 +/- 0.65] nmol/IU, P > 0.05), psychological status score (2.7 +/- 1.4 vs 2.9 +/- 1.2, P > 0.05), physi- cal status score (2.9 +/- 1.6 vs 3.1 +/- 1.5, P > 0.05) and sexual function score (4.5 +/- 2.9 vs 4.8 +/- 3.0, P > 0.05). There were no adverse events in either of the two groups throughout the whole experiment. The method of tonifying the kidney and activating blood circulation could significantly improve the clinical symptoms of LOH with kidney deficiency and increase the patient's serum TT level and TSI. NGN decoction works on LOH by acting on the hypothalamic-pituitary-gonad axis.

  1. Non-B DNA-forming sequences and WRN deficiency independently increase the frequency of base substitution in human cells

    DEFF Research Database (Denmark)

    Bacolla, Albino; Wang, Guliang; Jain, Aklank

    2011-01-01

    determined non-B DNA-induced mutation frequencies and spectra in human U2OS osteosarcoma cells and assessed the role of WRN in isogenic knockdown (WRN-KD) cells using a supF gene mutation reporter system flanked by triplex- or Z-DNA-forming sequences. Although both non-B DNA and WRN-KD served to increase...

  2. Impaired inflammatory response and increased oxidative stress and neurodegeneration after brain injury in interleukin-6-deficient mice

    DEFF Research Database (Denmark)

    Penkowa, M; Giralt, M; Carrasco, J;

    2000-01-01

    showed higher levels of MDA, NITT, and iNOS than did normal mice. Concomitantly, in IL-6KO mice the number of apoptotic neurons was significantly increased as judged by TUNEL staining, and regeneration of the tissue was delayed relative to normal mice. The changes in neuronal tissue damage and in brain...

  3. Deficiency of the DNA repair protein nibrin increases the basal but not the radiation induced mutation frequency in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wessendorf, Petra [Institute of Medical and Human Genetics, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany); Vijg, Jan [Albert Einstein College of Medicine, Michael F. Price Center, 1301 Morris Park Avenue, Bronx, NY 10461 (United States); Nussenzweig, André [Laboratory of Genome Integrity, National Cancer Institute, National Institute of Health, 37 Convent Drive, Room 1106, Bethesda, MD 20892 (United States); Digweed, Martin, E-mail: martin.digweed@charite.de [Institute of Medical and Human Genetics, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany)

    2014-11-15

    Highlights: • lacZ mutant frequencies measured in vivo in mouse models of radiosensitive Nijmegen Breakage Syndrome. • Spontaneous mutation frequencies are increased in lymphatic tissue due to Nbn mutation. • Single base transitions, not deletions, dominate the mutation spectrum. • Radiation induced mutation frequencies are not increased due to Nbn mutation. - Abstract: Nibrin (NBN) is a member of a DNA repair complex together with MRE11 and RAD50. The complex is associated particularly with the repair of DNA double strand breaks and with the regulation of cell cycle check points. Hypomorphic mutation of components of the complex leads to human disorders characterised by radiosensitivity and increased tumour occurrence, particularly of the lymphatic system. We have examined here the relationship between DNA damage, mutation frequency and mutation spectrum in vitro and in vivo in mouse models carrying NBN mutations and a lacZ reporter plasmid. We find that NBN mutation leads to increased spontaneous DNA damage in fibroblasts in vitro and high basal mutation rates in lymphatic tissue of mice in vivo. The characteristic mutation spectrum is dominated by single base transitions rather than the deletions and complex rearrangements expected after abortive repair of DNA double strand breaks. We conclude that in the absence of wild type nibrin, the repair of spontaneous errors, presumably arising during DNA replication, makes a major contribution to the basal mutation rate. This applies also to cells heterozygous for an NBN null mutation. Mutation frequencies after irradiation in vivo were not increased in mice with nibrin mutations as might have been expected considering the radiosensitivity of NBS patient cells in vitro. Evidently apoptosis is efficient, even in the absence of wild type nibrin.

  4. The effects of supplementing a low-protein threonine-deficient diet with different sources of non-essential amino acids on nitrogen retention and gut structure in young pigs.

    Science.gov (United States)

    Swiech, Ewa; Buraczewska, Lucyna; Tuśnio, Anna; Taciak, Marcin

    2010-02-01

    A threonine-adequate control diet and four Thr-deficient (80% of requirement) diets were formulated to contain similar amounts of digestible lysine and the recommended pattern of other standardised ileal digestible essential amino acids (except Thr). Threonine-deficient diets were supplemented with different amounts and sources of non-essential amino acids, namely 0, 20, and 40 g wheat gluten (WG) protein per kg diet or 17.6 g monosodium glutamate (MSG) per kg diet. Each diet was fed for 28 days to six piglets (initial BW 15 kg). Supplementation of the Thr-deficient diet with WG or MSG had a positive effect on N retention (5.9-8.5%) in younger, but not in older, pigs. Furthermore, it reduced the plasma Thr level and increased threonine dehydrogenase activity in the liver and pancreas. The treatment effects on intestinal morphology differed according to the histological criteria used. It may be concluded that non-essential amino acids added to the low-protein diet deficient in Thr seem to improve utilisation of these amino acids for protein deposition in very young pigs, whereas their effects on the structure of the small intestine are equivocal.

  5. Iron and Vitamin C Co-Supplementation Increased Serum Vitamin C Without Adverse Effect on Zinc Level in Iron Deficient Female Youth

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Khoshfetrat

    2014-01-01

    Full Text Available Background: Iron supplementation can decrease the absorption of zinc and influence other antioxidants levels such as vitamin C. This study aimed to investigate the effect of iron supplements alone and in combination with vitamin C on zinc and vitamin C status in iron deficient female students. Methods: In a double-blind randomized clinical trail, 60 iron deficient students were selected from 289 volunteers residing in dormitory. After matching, subjects were randomly assigned into two groups: Group I (50 mg elemental iron supplements and Group II (50 mg elemental iron + 500 mg ascorbic acid. Serum ferritin, iron, serum zinc, and plasma vitamin C concentrations were measured by using enzyme-linked immunosorbent assay, spectrophotometer, atomic absorption spectrometer, and colorimeter, respectively after 6 and 12 weeks supplementation. Student′s t-test and repeated measures analysis of variance were applied to analyze the data using SPSS software. Results: Serum zinc levels had no significant differences between 2 groups at the baseline; however, its concentration decreased from 80.9 ± 4.2-68.9 ± 2.7 μg/dl to 81.2 ± 4.5-66.1 ± 2.9 μg/dl (P < 0.001 in Groups I and II, respectively after 6 weeks of supplementation. Continuous supplementation increased serum zinc concentration to baseline levels (79.0 ± 2.9 μg/dl; P < 0.01 in Group I and 70.5 ± 3.1 μg/dl in Group II following 12 weeks of supplementation. Plasma vitamin C increased from 3 ± 0/1-3.3 ± 0.2 mg/dl to 2.7 ± 0. 1-4.2 ± 0.2 mg/dl (P < 0.01 in Groups I and II, respectively. At the end of study, plasma vitamin C significantly increased from 3.3 ± 0.3-4.7 ± 0.3 (P < 0.01 to 4.2 ± 0.2-7.1 ± 0.2 (P < 0.001 in Groups I and II, respectively. Conclusions: Iron supplementation with and without vitamin C led to reduction in serum Zn in iron-deficient female students after 6 weeks. However, the decreasing trend stops after repletion of iron stores and Zn levels returned to the

  6. Hepcidin levels are low during pregnancy and increase around delivery in women without iron deficiency - a prospective cohort study

    DEFF Research Database (Denmark)

    Hedengran, Katrine K; Nelson, Dick; Andersen, Malene R;

    2015-01-01

    OBJECTIVE: To investigate hepcidin during pregnancy, delivery and postpartum in women with sufficient iron supplementation. METHODS: Hepcidin was measured using LC-MS spectroscopy in 37 women during pregnancy, delivery and postpartum period in this longitudinal study. RESULTS: Hepcidin was low...... during pregnancy and increased at delivery and postpartum. No correlations with inflammatory markers or iron metabolism were observed during pregnancy; at delivery a correlation with inflammatory markers was observed. CONCLUSION: During pregnancy, in women with sufficient iron supplementation, hepcidin...... is low and does not reflect iron status. During delivery and the postpartum period, hepcidin functions as a marker of inflammation....

  7. Macrophage ABCA5 deficiency influences cellular cholesterol efflux and increases susceptibility to atherosclerosis in female LDLr knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Dan, E-mail: y.dan@lacdr.leidenuniv.nl [Division of Biopharmaceutics, LACDR, Leiden University (Netherlands); Meurs, Illiana [Division of Biopharmaceutics, LACDR, Leiden University (Netherlands); Ohigashi, Megumi [Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University (Japan); Calpe-Berdiel, Laura; Habets, Kim L.L.; Zhao, Ying [Division of Biopharmaceutics, LACDR, Leiden University (Netherlands); Kubo, Yoshiyuki [Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University (Japan); Yamaguchi, Akihito [Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University (Japan); Van Berkel, Theo J.C. [Division of Biopharmaceutics, LACDR, Leiden University (Netherlands); Nishi, Tsuyoshi [Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University (Japan); Van Eck, Miranda [Division of Biopharmaceutics, LACDR, Leiden University (Netherlands)

    2010-05-07

    Objectives: To determine the role of macrophage ATP-binding cassette transporter A5 (ABCA5) in cellular cholesterol homeostasis and atherosclerotic lesion development. Methods and results: Chimeras with dysfunctional macrophage ABCA5 (ABCA5{sup -M/-M}) were generated by transplantation of bone marrow from ABCA5 knockout (ABCA5{sup -/-}) mice into irradiated LDLr{sup -/-} mice. In vitro, bone marrow-derived macrophages from ABCA5{sup -M/-M} chimeras exhibited a 29% (P < 0.001) decrease in cholesterol efflux to HDL, whereas a 21% (P = 0.07) increase in cholesterol efflux to apoA-I was observed. Interestingly, expression of ABCA1, but not ABCG1, was up-regulated in absence of functional ABCA5 in macrophages. To induce atherosclerosis, the transplanted LDLr{sup -/-} mice were fed a high-cholesterol Western-type diet (WTD) for 6, 10, or 18 weeks, allowing analysis of effects on initial as well as advanced lesion development. Atherosclerosis development was not affected in male ABCA5{sup -M/-M} chimeras after 6, 10, and 18 weeks WTD feeding. However, female ABCA5{sup -M/-M} chimeras did develop significantly (P < 0.05) larger aortic root lesions as compared with female controls after 6 and 10 weeks WTD feeding. Conclusions: ABCA5 influences macrophage cholesterol efflux, and selective disruption of ABCA5 in macrophages leads to increased atherosclerotic lesion development in female LDLr{sup -/-} mice.

  8. In pulmonary paracoccidioidomycosis IL-10 deficiency leads to increased immunity and regressive infection without enhancing tissue pathology.

    Directory of Open Access Journals (Sweden)

    Tânia A Costa

    Full Text Available BACKGROUND: Cellular immunity is the main defense mechanism in paracoccidioidomycosis (PCM, the most important systemic mycosis in Latin America. Th1 immunity and IFN-γ activated macrophages are fundamental to immunoprotection that is antagonized by IL-10, an anti-inflammatory cytokine. Both in human and experimental PCM, several evidences indicate that the suppressive effect of IL-10 causes detrimental effects to infected hosts. Because direct studies have not been performed, this study was aimed to characterize the function of IL-10 in pulmonary PCM. METHODOLOGY/PRINCIPAL FINDINGS: Wild type (WT and IL-10(-/- C57BL/6 mice were used to characterize the role of IL-10 in the innate and adaptive immunity against Paracoccidioides brasiliensis (Pb infection. We verified that Pb-infected peritoneal macrophages from IL-10(-/- mice presented higher phagocytic and fungicidal activities than WT macrophages, and these activities were associated with elevated production of IFN-γ, TNF-α, nitric oxide (NO and MCP-1. For in vivo studies, IL-10(-/- and WT mice were i.t. infected with 1×10(6 Pb yeasts and studied at several post-infection periods. Compared to WT mice, IL-10(-/- mice showed increased resistance to P. brasiliensis infection as determined by the progressive control of pulmonary fungal loads and total clearance of fungal cells from dissemination organs. This behavior was accompanied by enhanced delayed-type hypersensitivity reactions, precocious humoral immunity and controlled tissue pathology resulting in increased survival times. In addition, IL-10(-/- mice developed precocious T cell immunity mediated by increased numbers of lung infiltrating effector/memory CD4(+ and CD8(+ T cells. The inflammatory reactions and the production of Th1/Th2/Th17 cytokines were reduced at late phases of infection, paralleling the regressive infection of IL-10(-/- mice. CONCLUSIONS/SIGNIFICANCE: Our work demonstrates for the first time that IL-10 plays a

  9. In pulmonary paracoccidioidomycosis IL-10 deficiency leads to increased immunity and regressive infection without enhancing tissue pathology.

    Directory of Open Access Journals (Sweden)

    Tânia A Costa

    Full Text Available BACKGROUND: Cellular immunity is the main defense mechanism in paracoccidioidomycosis (PCM, the most important systemic mycosis in Latin America. Th1 immunity and IFN-γ activated macrophages are fundamental to immunoprotection that is antagonized by IL-10, an anti-inflammatory cytokine. Both in human and experimental PCM, several evidences indicate that the suppressive effect of IL-10 causes detrimental effects to infected hosts. Because direct studies have not been performed, this study was aimed to characterize the function of IL-10 in pulmonary PCM. METHODOLOGY/PRINCIPAL FINDINGS: Wild type (WT and IL-10(-/- C57BL/6 mice were used to characterize the role of IL-10 in the innate and adaptive immunity against Paracoccidioides brasiliensis (Pb infection. We verified that Pb-infected peritoneal macrophages from IL-10(-/- mice presented higher phagocytic and fungicidal activities than WT macrophages, and these activities were associated with elevated production of IFN-γ, TNF-α, nitric oxide (NO and MCP-1. For in vivo studies, IL-10(-/- and WT mice were i.t. infected with 1×10(6 Pb yeasts and studied at several post-infection periods. Compared to WT mice, IL-10(-/- mice showed increased resistance to P. brasiliensis infection as determined by the progressive control of pulmonary fungal loads and total clearance of fungal cells from dissemination organs. This behavior was accompanied by enhanced delayed-type hypersensitivity reactions, precocious humoral immunity and controlled tissue pathology resulting in increased survival times. In addition, IL-10(-/- mice developed precocious T cell immunity mediated by increased numbers of lung infiltrating effector/memory CD4(+ and CD8(+ T cells. The inflammatory reactions and the production of Th1/Th2/Th17 cytokines were reduced at late phases of infection, paralleling the regressive infection of IL-10(-/- mice. CONCLUSIONS/SIGNIFICANCE: Our work demonstrates for the first time that IL-10 plays a

  10. Interleukin-6 deficiency reduces the brain inflammatory response and increases oxidative stress and neurodegeneration after kainic acid-induced seizures

    DEFF Research Database (Denmark)

    Penkowa, M; Molinero, A; Carrasco, J

    2001-01-01

    , the immunoreactivity for inducible nitric oxide synthase, peroxynitrite-induced nitration of proteins and byproducts of fatty acid peroxidation were dramatically increased, as was that for metallothionein I+II, Mn-superoxide dismutase and Cu/Zn-superoxide dismutase. In accordance, a significant neuronal apoptosis...... was caused by kainic acid, as revealed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling and interleukin-1beta converting enzyme/Caspase-1 stainings. In kainic acid-injected interleukin-6 null mice, reactive astrogliosis and microgliosis were reduced, while......The role of interleukin-6 in hippocampal tissue damage after injection with kainic acid, a rigid glutamate analogue inducing epileptic seizures, has been studied by means of interleukin-6 null mice. At 35mg/kg, kainic acid induced convulsions in both control (75%) and interleukin-6 null (100%) mice...

  11. Increased mitochondrial function downstream from KDM5A histone demethylase rescues differentiation in pRB-deficient cells.

    Science.gov (United States)

    Váraljai, Renáta; Islam, Abul B M M K; Beshiri, Michael L; Rehman, Jalees; Lopez-Bigas, Nuria; Benevolenskaya, Elizaveta V

    2015-09-01

    The retinoblastoma tumor suppressor protein pRb restricts cell growth through inhibition of cell cycle progression. Increasing evidence suggests that pRb also promotes differentiation, but the mechanisms are poorly understood, and the key question remains as to how differentiation in tumor cells can be enhanced in order to diminish their aggressive potential. Previously, we identified the histone demethylase KDM5A (lysine [K]-specific demethylase 5A), which demethylates histone H3 on Lys4 (H3K4), as a pRB-interacting protein counteracting pRB's role in promoting differentiation. Here we show that loss of Kdm5a restores differentiation through increasing mitochondrial respiration. This metabolic effect is both necessary and sufficient to induce the expression of a network of cell type-specific signaling and structural genes. Importantly, the regulatory functions of pRB in the cell cycle and differentiation are distinct because although restoring differentiation requires intact mitochondrial function, it does not necessitate cell cycle exit. Cells lacking Rb1 exhibit defective mitochondria and decreased oxygen consumption. Kdm5a is a direct repressor of metabolic regulatory genes, thus explaining the compensatory role of Kdm5a deletion in restoring mitochondrial function and differentiation. Significantly, activation of mitochondrial function by the mitochondrial biogenesis regulator Pgc-1α (peroxisome proliferator-activated receptor γ-coactivator 1α; also called PPARGC1A) a coactivator of the Kdm5a target genes, is sufficient to override the differentiation block. Overexpression of Pgc-1α, like KDM5A deletion, inhibits cell growth in RB-negative human cancer cell lines. The rescue of differentiation by loss of KDM5A or by activation of mitochondrial biogenesis reveals the switch to oxidative phosphorylation as an essential step in restoring differentiation and a less aggressive cancer phenotype.

  12. Increased densities of binding sites for the peripheral-type benzodiazepine receptor ligand [3H]PK 11195 in congenital ornithine transcarbamylase-deficient sparse fur mouse.

    Science.gov (United States)

    Rao, V L; Qureshi, I A; Butterworth, R F

    1993-12-01

    Peripheral-type (mitochondrial) benzodiazepine receptors (PTBR) were studied in the brain and peripheral organs (kidney, liver, and testis) of normal male mice (CD-1/Y) and the congenitally hyperammonemic sparse fur (spf/Y) mouse. Radioligand binding assays were performed with [3H]PK 11195, a ligand with high selectivity and affinity for PTBR. Densities (maximal number of binding sites) of [3H]PK 11195 binding sites were greatest in kidney, followed by liver, testis, and brain. Densities of [3H]PK 11195 binding sites were significantly increased in all tissues of spf mice compared with control animals. In view of the localization of PTBR on the outer mitochondrial membrane, changes in PTBR in spf mouse tissues may modulate the altered mitochondrial function and oxidative metabolism, in brain and peripheral tissues, in congenital OTC deficiency. The positron emission tomography ligand 11C-PK 11195 could find an application in the assessment of end organ dysfunction in this disorder.

  13. Gamma-H2AX upregulation caused by Wip1 deficiency increases depression-related cellular senescence in hippocampus

    Science.gov (United States)

    He, Zhi-Yong; Wang, Wen-Yue; Hu, Wei-Yan; Yang, Lu; Li, Yan; Zhang, Wei-Yuan; Yang, Ya-Shu; Liu, Si-Cheng; Zhang, Feng-Lan; Mei, Rong; Xing, Da; Xiao, Zhi-Cheng; Zhang, Ming

    2016-01-01

    The PP2C family member Wild-type p53-induced phosphatase 1 (Wip1) critically regulates DNA damage response (DDR) under stressful situations. In the present study, we investigated whether Wip1 expression was involved in the regulation of DDR-induced and depression-related cellular senescence in mouse hippocampus. We found that Wip1 gene knockout (KO) mice showed aberrant elevation of hippocampal cellular senescence and of γ-H2AX activity, which is known as a biomarker of DDR and cellular senescence, indicating that the lack of Wip1-mediated γ-H2AX dephosphorylation facilitates cellular senescence in hippocampus. Administration of the antidepressant fluoxetine had no significant effects on the increased depression-like behaviors, enriched cellular senescence, and aberrantly upregulated hippocampal γ-H2AX activity in Wip1 KO mice. After wildtype C57BL/6 mice were exposed to the procedure of chronic unpredictable mild stress (CUMS), cellular senescence and γ-H2AX activity in hippocampus were also elevated, accompanied by the suppression of Wip1 expression in hippocampus when compared to the control group without CUMS experience. These CUMS-induced symptoms were effectively prevented following fluoxetine administration in wildtype C57BL/6 mice, with the normalization of depression-like behaviors. Our data demonstrate that Wip1-mediated γ-H2AX dephosphorylation may play an important role in the occurrence of depression-related cellular senescence. PMID:27686532

  14. Prep1 deficiency induces protection from diabetes and increased insulin sensitivity through a p160-mediated mechanism.

    Science.gov (United States)

    Oriente, Francesco; Fernandez Diaz, Luis Cesar; Miele, Claudia; Iovino, Salvatore; Mori, Silvia; Diaz, Victor Manuel; Troncone, Giancarlo; Cassese, Angela; Formisano, Pietro; Blasi, Francesco; Beguinot, Francesco

    2008-09-01

    We have examined glucose homeostasis in mice hypomorphic for the homeotic transcription factor gene Prep1. Prep1-hypomorphic (Prep1(i/i)) mice exhibit an absolute reduction in circulating insulin levels but normal glucose tolerance. In addition, these mice exhibit protection from streptozotocin-induced diabetes and enhanced insulin sensitivity with improved glucose uptake and insulin-dependent glucose disposal by skeletal muscle. This muscle phenotype does not depend on reduced expression of the known Prep1 transcription partner, Pbx1. Instead, in Prep1(i/i) muscle, we find normal Pbx1 but reduced levels of the recently identified novel Prep1 interactor p160. Consistent with this reduction, we find a muscle-selective increase in mRNA and protein levels of PGC-1alpha, accompanied by enhanced expression of the GLUT4 transporter, responsible for insulin-stimulated glucose uptake in muscle. Indeed, using L6 skeletal muscle cells, we induced the opposite effects by overexpressing Prep1 or p160, but not Pbx1. In vivo skeletal muscle delivery of p160 cDNA in Prep1(i/i) mice also reverses the molecular phenotype. Finally, we show that Prep1 controls the stability of the p160 protein. We conclude that Prep1 controls insulin sensitivity through the p160-GLUT4 pathway.

  15. Nucleotide excision repair deficiency increases levels of acrolein-derived cyclic DNA adduct and sensitizes cells to apoptosis induced by docosahexaenoic acid and acrolein.

    Science.gov (United States)

    Pan, Jishen; Sinclair, Elizabeth; Xuan, Zhuoli; Dyba, Marcin; Fu, Ying; Sen, Supti; Berry, Deborah; Creswell, Karen; Hu, Jiaxi; Roy, Rabindra; Chung, Fung-Lung

    2016-07-01

    The acrolein derived cyclic 1,N(2)-propanodeoxyguanosine adduct (Acr-dG), formed primarily from ω-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) under oxidative conditions, while proven to be mutagenic, is potentially involved in DHA-induced apoptosis. The latter may contribute to the chemopreventive effects of DHA. Previous studies have shown that the levels of Acr-dG are correlated with apoptosis induction in HT29 cells treated with DHA. Because Acr-dG is shown to be repaired by the nucleotide excision repair (NER) pathway, to further investigate the role of Acr-dG in apoptosis, in this study, NER-deficient XPA and its isogenic NER-proficient XAN1 cells were treated with DHA. The Acr-dG levels and apoptosis were sharply increased in XPA cells, but not in XAN1 cells when treated with 125μM of DHA. Because DHA can induce formation of various DNA damage, to specifically investigate the role of Acr-dG in apoptosis induction, we treated XPA knockdown HCT116+ch3 cells with acrolein. The levels of both Acr-dG and apoptosis induction increased significantly in the XPA knockdown cells. These results clearly demonstrate that NER deficiency induces higher levels of Acr-dG in cells treated with DHA or acrolein and sensitizes cells to undergo apoptosis in a correlative manner. Collectively, these results support that Acr-dG, a ubiquitously formed mutagenic oxidative DNA adduct, plays a role in DHA-induced apoptosis and suggest that it could serve as a biomarker for the cancer preventive effects of DHA.

  16. Vitamin C deficiency in the brain impairs cognition, increases amyloid accumulation and deposition, and oxidative stress in APP/PSEN1 and normally aging mice.

    Science.gov (United States)

    Dixit, Shilpy; Bernardo, Alexandra; Walker, Jennifer Michelle; Kennard, John Andrew; Kim, Grace Youngeun; Kessler, Eric Sean; Harrison, Fiona Edith

    2015-04-15

    Subclinical vitamin C deficiency is widespread in many populations, but its role in both Alzheimer's disease and normal aging is understudied. In the present study, we decreased brain vitamin C in the APPSWE/PSEN1deltaE9 mouse model of Alzheimer's disease by crossing APP/PSEN1(+) bigenic mice with SVCT2(+/-) heterozygous knockout mice, which have lower numbers of the sodium-dependent vitamin C transporter required for neuronal vitamin C transport. SVCT2(+/-) mice performed less well on the rotarod task at both 5 and 12 months of age compared to littermates. SVCT2(+/-) and APP/PSEN1(+) mice and the combination genotype SVCT2(+/-)APP/PSEN1(+) were also impaired on multiple tests of cognitive ability (olfactory memory task, Y-maze alternation, conditioned fear, Morris water maze). In younger mice, both low vitamin C (SVCT2(+/-)) and APP/PSEN1 mutations increased brain cortex oxidative stress (malondialdehyde, protein carbonyls, F2-isoprostanes) and decreased total glutathione compared to wild-type controls. SVCT2(+/-) mice also had increased amounts of both soluble and insoluble Aβ1-42 and a higher Aβ1-42/1-40 ratio. By 14 months of age, oxidative stress levels were similar among groups, but there were more amyloid-β plaque deposits in both hippocampus and cortex of SVCT2(+/-)APP/PSEN1(+) mice compared to APP/PSEN1(+) mice with normal brain vitamin C. These data suggest that even moderate intracellular vitamin C deficiency plays an important role in accelerating amyloid pathogenesis, particularly during early stages of disease development, and that these effects are likely modulated by oxidative stress pathways.

  17. Terrestrial nitrogen cycles: Some unanswered questions

    Science.gov (United States)

    Vitousek, P.

    1984-01-01

    Nitrogen is generally considered to be the element which most often limits the growth of plants in both natural and agricultural ecosystems. It regulates plant growth because photosynthetic rates are strongly dependent on the concentration of nitrogen in leaves, and because relatively large mounts of protein are required for cell division and growth. Yet nitrogen is abundant in the biosphere - the well-mixed pool in the atmosphere is considered inexhaustible compared to biotic demand, and the amount of already fixed organic nitrogen in soils far exceeds annual plant uptake in terrestrial ecosystems. In regions where natural vegetation is not nitrogen limited, continuous cultivation induces nitrogen deficiency. Nitrogen loss from cultivated lands is more rapid than that of other elements, and nitrogen fertilization is generally required to maintain crop yield under any continuous system. The pervasiveness of nitrogen deficiency in many natural and most managed sites is discussed.

  18. Adult mortality or morbidity is not increased in childhood-onset growth hormone deficient patients who received pediatric GH treatment: an analysis of the Hypopituitary Control and Complications Study (HypoCCS)

    OpenAIRE

    Mo, Daojun; Hardin, Dana Sue; Erfurth, Eva Marie; Melmed, Shlomo

    2013-01-01

    Background The French Safety and Appropriateness of Growth Hormone treatments in Europe (SAGhE) cohort has raised concern of increased mortality risk during follow-up into adulthood in certain patients who had received growth hormone (GH) treatment during childhood. The Hypopituitary Control and Complications Study monitored mortality and morbidity of adult GH-deficient patients including those with childhood-onset GH deficiency (COGHD) who received GH treatment as children. Purpose Evaluate ...

  19. Responses of CH(4), CO(2) and N(2)O fluxes to increasing nitrogen deposition in alpine grassland of the Tianshan Mountains.

    Science.gov (United States)

    Li, Kaihui; Gong, Yanming; Song, Wei; He, Guixiang; Hu, Yukun; Tian, Changyan; Liu, Xuejun

    2012-06-01

    To assess the effects of nitrogen (N) deposition on greenhouse gas (GHG) fluxes in alpine grassland of the Tianshan Mountains in central Asia, CH(4), CO(2) and N(2)O fluxes were measured from June 2010 to May 2011. Nitrogen deposition tended to significantly increase CH(4) uptake, CO(2) and N(2)O emissions at sites receiving N addition compared with those at site without N addition during the growing season, but no significant differences were found for all sites outside the growing season. Air temperature, soil temperature and water content were the important factors that influence CO(2) and N(2)O emissions at year-round scale, indicating that increased temperature and precipitation in the future will exert greater impacts on CO(2) and N(2)O emissions in the alpine grassland. In addition, plant coverage in July was also positively correlated with CO(2) and N(2)O emissions under elevated N deposition rates. The present study will deepen our understanding of N deposition impacts on GHG balance in the alpine grassland ecosystem, and help us assess the global N effects, parameterize Earth System models and inform decision makers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Use of laboratory anaerobic digesters to simulate the increase of treatment rate in full-scale high nitrogen content sewage sludge and co-digestion biogas plants.

    Science.gov (United States)

    Tampio, Elina; Ervasti, Satu; Paavola, Teija; Rintala, Jukka

    2016-11-01

    The aim of this study was to assess the effect of increasing feedstock treatment rate on the performance of full-scale anaerobic digestion using laboratory-scale reactors with digestate and feedstock from full-scale digesters. The studied nitrogen-containing feedstocks were i) a mixture of industrial by-products and pig slurry, and ii) municipal sewage sludge, which digestion was studied at 41 and 52°C, respectively. This study showed the successful reduction of hydraulic retention times from 25 and 20days to around 15days, which increased organic loading rates from 2 to 3.5kg volatile solids (VS)/m(3)d and 4 to 6kgVS/m(3)d. As a result, the optimum retention time in terms of methane production and VS removal was 10-15% lower than the initial in the full-scale digesters. Accumulation of acids during start-up of the co-digestion reactor was suggested to be connected to the high ammonium nitrogen concentration and intermediate temperature of 41°C.

  1. Increased Salinity Tolerance of Cowpea Plants by Dual Inoculation of an Arbuscular Mycorrhizal Fungus Glomus clarum and a Nitrogen-fixer Azospirillum brasilense.

    Science.gov (United States)

    Rabie, G H; Aboul-Nasr, M B; Al-Humiany, A

    2005-03-01

    Pot greenhouse experiments were carried out to attempt to increase the salinity tolerance of one of the most popular legume of the world; cowpea; by using dual inoculation of an Am fungus Glomus clarum and a nitrogen-fixer Azospirillum brasilense. The effect of these beneficial microbes, as single- or dual inoculation-treatments, was assessed in sterilized loamy sand soil at five NaCl levels (0.0~7.2 ds/m) in irrigating water. The results of this study revealed that percentage of mycorrhizal infection, plant height, dry weight, nodule number, protein content, nitrogenase and phosphatase activities, as well as nutrient elements N, P, K, Ca, Mg were significantly decreased by increasing salinity level in non-mycorrhized plants in absence of NFB. Plants inoculated with NFB showed higher nodule numbers, protein content, nitrogen concentration and nitrogenase activities than those of non-inoculated at all salinity levels. Mycorrhized plants exhibited better improvement in all measurements than that of non-mycorrhized ones at all salinity levels, especially, in the presence of NFB. The concentration of Na(+) was significantly accumulated in cowpea plants by rising salinity except in shoots of mycorrhizal plants which had K(+)/Na(+) ratios higher than other treatments. This study indicated that dual inoculation with Am fungi and N-fixer Azospirillum can support both needs for N and P, excess of NaCl and will be useful in terms of soil recovery in saline area.

  2. Dark septate root endophytic fungi increase growth of Scots pine seedlings under elevated CO2 through enhanced nitrogen use efficiency.

    NARCIS (Netherlands)

    Alberton, O.; Kuyper, T.W.; Summerbell, R.C.

    2010-01-01

    Although increasing concentrations of atmospheric CO2 are predicted to have substantial impacts on plant growth and functioning of ecosystems, there is insufficient understanding of the responses of belowground processes to such increases. We investigated the effects of different dark septate root e

  3. Iodine Deficiency

    Science.gov (United States)

    ... 2017 By ATA | Featured , Iodine Deficiency , News Releases , Potassium Iodide (KI) | No Comments IDD NEWSLETTER – February 2017 VOLUME ... 2016 By ATA | Featured , Iodine Deficiency , News Releases , Potassium Iodide (KI) | No Comments IDD NEWSLETTER – November 2015 (PDF ...

  4. Modelling changes in nitrogen cycling to sustain increases in forest productivity under elevated atmospheric CO2 and contrasting site conditions

    Science.gov (United States)

    Grant, R. F.

    2013-11-01

    If increases in net primary productivity (NPP) caused by rising concentrations of atmospheric CO2 (Ca) are to be sustained, key N processes such as soil mineralization, biological fixation, root uptake and nutrient conservation must also be increased. Simulating the response of these processes to elevated Ca is therefore vital for models used to project the effects of rising Ca on NPP. In this modelling study, hypotheses are proposed for changes in soil mineralization, biological fixation, root nutrient uptake and plant nutrient conservation with changes in Ca. Algorithms developed from these hypotheses were tested in the ecosystem model ecosys against changes in N and C cycling measured over several years under ambient vs. elevated Ca in Free Air CO2 Enrichment (FACE) experiments in the USA at the Duke Forest in North Carolina, the Oak Ridge National Laboratory forest in Tennessee, and the USDA research forest in Wisconsin. More rapid soil N mineralization was found to be vital for simulating sustained increases in NPP measured under elevated vs. ambient Ca at all three FACE sites. This simulation was accomplished by priming decomposition of N-rich humus from increases in microbial biomass generated by increased litterfall modelled under elevated Ca. Greater nonsymbiotic N2 fixation from increased litterfall, root N uptake from increased root growth, and plant N conservation from increased translocation under elevated Ca were found to make smaller contributions to simulated increases in NPP. However greater nutrient conservation enabled larger increases in NPP with Ca to be modelled with coniferous vs. deciduous plant functional types. The effects of these processes on productivity now need to be examined over longer periods under transient rises in Ca and a greater range of site conditions.

  5. Combined Increases in Mitochondrial Cooperation and Oxygen Photoreduction Compensate for Deficiency in Cyclic Electron Flow in Chlamydomonas reinhardtii[W][OPEN

    Science.gov (United States)

    Dang, Kieu-Van; Plet, Julie; Tolleter, Dimitri; Jokel, Martina; Cuiné, Stéphan; Carrier, Patrick; Auroy, Pascaline; Richaud, Pierre; Johnson, Xenie; Alric, Jean; Allahverdiyeva, Yagut; Peltier, Gilles

    2014-01-01

    During oxygenic photosynthesis, metabolic reactions of CO2 fixation require more ATP than is supplied by the linear electron flow operating from photosystem II to photosystem I (PSI). Different mechanisms, such as cyclic electron flow (CEF) around PSI, have been proposed to participate in reequilibrating the ATP/NADPH balance. To determine the contribution of CEF to microalgal biomass productivity, here, we studied photosynthesis and growth performances of a knockout Chlamydomonas reinhardtii mutant (pgrl1) deficient in PROTON GRADIENT REGULATION LIKE1 (PGRL1)–mediated CEF. Steady state biomass productivity of the pgrl1 mutant, measured in photobioreactors operated as turbidostats, was similar to its wild-type progenitor under a wide range of illumination and CO2 concentrations. Several changes were observed in pgrl1, including higher sensitivity of photosynthesis to mitochondrial inhibitors, increased light-dependent O2 uptake, and increased amounts of flavodiiron (FLV) proteins. We conclude that a combination of mitochondrial cooperation and oxygen photoreduction downstream of PSI (Mehler reactions) supplies extra ATP for photosynthesis in the pgrl1 mutant, resulting in normal biomass productivity under steady state conditions. The lower biomass productivity observed in the pgrl1 mutant in fluctuating light is attributed to an inability of compensation mechanisms to respond to a rapid increase in ATP demand. PMID:24989042

  6. Mild riboflavin deficiency is highly prevalent in school-age children but does not increase risk for anaemia in Cote d'Ivoire

    NARCIS (Netherlands)

    Rohner, F.; Zimmermann, M.B.; Wegmueller, R.; Tschannen, A.B.; Hurrell, R.F.

    2007-01-01

    There are few data on the prevalence of riboflavin deficiency in sub-Saharan Africa, and it remains unclear whether riboflavin status influences the risk for anaemia. The aims of this study were to: (1) measure the prevalence of riboflavin deficiency in children in south-central Côte d'Ivoire; (2) e

  7. Mild riboflavin deficiency is highly prevalent in school-age children but does not increase risk for anaemia in Cote d'Ivoire

    NARCIS (Netherlands)

    Rohner, F.; Zimmermann, M.B.; Wegmueller, R.; Tschannen, A.B.; Hurrell, R.F.

    2007-01-01

    There are few data on the prevalence of riboflavin deficiency in sub-Saharan Africa, and it remains unclear whether riboflavin status influences the risk for anaemia. The aims of this study were to: (1) measure the prevalence of riboflavin deficiency in children in south-central Côte d'Ivoire; (2)

  8. Hydrogen peroxide alleviates nickel-inhibited photosynthetic responses through increase in use-efficiency of nitrogen and sulfur, and glutathione production in mustard

    Directory of Open Access Journals (Sweden)

    M Iqbal R Khan

    2016-02-01

    Full Text Available The response of two mustard (Brassica juncea L. cultivars differing in photosynthetic capacity to different concentrations of hydrogen peroxide (H2O2 or nickel (Ni was evaluated. Further, the effect of H2O2 on photosynthetic responses of the mustard cultivars grown with or without Ni stress was studied. Application of 50 µM H2O2 increased photosynthesis and growth more prominently in high photosynthetic capacity cultivar (Varuna than low photosynthetic capacity cultivar (RH30 grown without Ni stress. The H2O2 application also resulted in alleviation of photosynthetic inhibition induced by 200 mg Ni kg-1 soil through increased photosynthetic nitrogen-use efficiency (NUE, sulfur-use efficiency (SUE, and glutathione (GSH reduced production together with decreased lipid peroxidation and electrolyte leakage in both the cultivars. However, the effect of H2O2 was more pronounced in Varuna than RH30. The greater increase in photosynthetic-NUE and SUE and GSH production with H2O2 in Varuna resulted from higher increase in activity of nitrogen (N and sulfur (S assimilation enzymes, nitrate reductase and ATP-sulfurylase, respectively resulting in enhanced N and S assimilation. The increased N and S content contributed to the higher activity of ribulose-1,5-bisphosphate carboxylase (Rubisco under Ni stress. Application of H2O2 also regulated PS II activity and stomatal movement under Ni stress for maintaining higher photosynthetic potential in Varuna. Thus, H2O2 may be considered as a potential signaling molecule for augmenting photosynthetic potential of mustard plants under optimal and Ni stress conditions. It alleviates Ni stress through the regulation of stomatal and non-stomotal limitations, and photosynthetic-NUE and -SUE and GSH production.

  9. SLAP deficiency increases TCR avidity leading to altered repertoire and negative selection of cognate antigen-specific CD8+ T cells.

    Science.gov (United States)

    Friend, Samantha F; Peterson, Lisa K; Kedl, Ross M; Dragone, Leonard L

    2013-03-01

    How T cell receptor (TCR) avidity influences CD8(+) T cell development and repertoire selection is not yet fully understood. To fill this gap, we utilized Src-like adaptor protein (SLAP)-deficient mice as a tool to increase TCR avidity on double positive (DP) thymocytes. We generated SLAP(-/-) mice with the transgenic MHC class I-restricted TCR (OT-1) and SLAP(-/-) Vβ5 mice, expressing only the β-chain of the TCR OT-1 transgene, to examine the effects of increased TCR surface levels on CD8(+) T cell development and repertoire selection. In comparing SLAP(-/-) OT-1 and Vβ5 mice with wild-type controls, we performed compositional analysis and assessed thymocyte signaling by measuring CD5 levels. In addition, we performed tetramer and compositional staining to measure affinity for the cognate antigen, ovalbumin (OVA) peptide, presented by MHC. Furthermore, we quantified differences in α-chain repertoire in SLAP(-/-) Vβ5 mice. We have found that SLAP(-/-) OT-1 mice have fewer CD8(+) thymocytes but have increased CD5 expression. SLAP(-/-) OT-1 mice have fewer DP thymocytes expressing Vα2, signifying increased endogenous α-chain rearrangement, and more non-OVA-specific CD8(+) splenocytes upon tetramer staining. Our data demonstrate that SLAP(-/-) Vβ5 mice also have fewer OVA-specific cells and increased Vα2 usage in the peripheral Vβ5 CD8(+) T cells that were non-OVA-specific, demonstrating differences in α-chain repertoire. These studies provide direct evidence that increased TCR avidity in DP thymocytes enhances CD8(+) T cell negative selection deleting thymocytes with specificity for cognate antigen, an antigen the mature T cells may never encounter. Collectively, these studies provide new insights into how TCR avidity during CD8(+) T cell development influences repertoire selection.

  10. Comparison of Nitrogen Depletion and Repletion on Lipid Production in Yeast and Fungal Species

    Directory of Open Access Journals (Sweden)

    Shihui Yang

    2016-08-01

    Full Text Available Although it is well known that low nitrogen stimulates lipid accumulation, especially for algae and some oleaginous yeast, few studies have been conducted in fungal species, especially on the impact of different nitrogen deficiency strategies. In this study, we use two promising consolidated bioprocessing (CBP candidates to examine the impact of two nitrogen deficiency strategies on lipid production, which are the extensively investigated oleaginous yeast Yarrowia lipolytica, and the commercial cellulase producer Trichoderma reesei. We first utilized bioinformatics approaches to reconstruct the fatty acid metabolic pathway and demonstrated the presence of a triacylglycerol (TAG biosynthesis pathway in Trichoderma reesei. We then examined the lipid production of Trichoderma reesei and Y. lipomyces in different media using two nitrogen deficiency strategies of nitrogen natural repletion and nitrogen depletion through centrifugation. Our results demonstrated that nitrogen depletion was better than nitrogen repletion with about 30% lipid increase for Trichoderma reesei and Y. lipomyces, and could be an option to improve lipid production in both oleaginous yeast and filamentous fungal species. The resulting distinctive lipid composition profiles indicated that the impacts of nitrogen depletion on yeast were different from those for fungal species. Under three types of C/N ratio conditions, C16 and C18 fatty acids were the predominant forms of lipids for both Trichoderma reesei and Y. lipolytica. While the overall fatty acid methyl ester (FAME profiles of Trichoderma reesei were similar, the overall FAME profiles of Y. lipolytica observed a shift. The fatty acid metabolic pathway reconstructed in this work supports previous reports of lipid production in T. reesei, and provides a pathway for future omics studies and metabolic engineering efforts. Further investigation to identify the genetic targets responsible for the effect of nitrogen depletion on

  11. MTHFR deficiency or reduced intake of folate or choline in pregnant mice results in impaired short-term memory and increased apoptosis in the hippocampus of wild-type offspring.

    Science.gov (United States)

    Jadavji, N M; Deng, L; Malysheva, O; Caudill, M A; Rozen, R

    2015-08-06

    Genetic or nutritional disturbances in one-carbon metabolism, with associated hyperhomocysteinemia, can result in complex disorders including pregnancy complications and neuropsychiatric diseases. In earlier work, we showed that mice with a complete deficiency of methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate and homocysteine metabolism, had cognitive impairment with disturbances in choline metabolism. Maternal demands for folate and choline are increased during pregnancy and deficiencies of these nutrients result in several negative outcomes including increased resorption and delayed development. The goal of this study was to investigate the behavioral and neurobiological impact of a maternal genetic deficiency in MTHFR or maternal nutritional deficiency of folate or choline during pregnancy on 3-week-old Mthfr(+/+) offspring. Mthfr(+/+) and Mthfr(+/-) females were placed on control diets (CD); and Mthfr(+/+) females were placed on folate-deficient diets (FD) or choline-deficient diets (ChDD) throughout pregnancy and lactation until their offspring were 3weeks of age. Short-term memory was assessed in offspring, and hippocampal tissue was evaluated for morphological changes, apoptosis, proliferation and choline metabolism. Maternal MTHFR deficiency resulted in short-term memory impairment in offspring. These dams had elevated levels of plasma homocysteine when compared with wild-type dams. There were no differences in plasma homocysteine in offspring. Increased apoptosis and proliferation was observed in the hippocampus of offspring from Mthfr(+/-) mothers. In the maternal FD and ChDD study, offspring also showed short-term memory impairment with increased apoptosis in the hippocampus; increased neurogenesis was observed in ChDD offspring. Choline acetyltransferase protein was increased in the offspring hippocampus of both dietary groups and betaine was decreased in the hippocampus of FD offspring. Our results reveal short-term memory

  12. Effects of Increased Nitrogen Availability on C and N Cycles in Tropical Forests: A Meta-Analysis.

    Science.gov (United States)

    Bejarano-Castillo, Marylin; Campo, Julio; Roa-Fuentes, Lilia L

    2015-01-01

    Atmospheric N deposition is predicted to increase four times over its current status in tropical forests by 2030. Our ability to understand the effects of N enrichment on C and N cycles is being challenged by the large heterogeneity of the tropical forest biome. The specific response will depend on the forest's nutrient status; however, few studies of N addition appear to incorporate the nutrient status in tropical forests, possibly due to difficulties in explaining how this status is maintained. We used a meta-analysis to explore the consequences of the N enrichment on C and N cycles in tropical montane and lowland forests. We tracked changes in aboveground and belowground plant C and N and in mineral soil in response to N addition. We found an increasing trend of plant biomass in montane forests, but not in lowland forests, as well as a greater increase in NO emission in montane forest compared with lowland forest. The N2O and NO emission increase in both forest; however, the N2O increase in lowland forest was significantly even at first time N addition. The NO emission increase showed be greater at first term compared with long term N addition. Moreover, the increase in total soil N, ammonium, microbial N, and dissolved N concentration under N enrichment indicates a rich N status of lowland forests. The available evidence of N addition experiments shows that the lowland forest is richer in N than montane forests. Finally, the greater increase in N leaching and N gas emission highlights the importance of study the N deposition effect on the global climate change.

  13. Modelling changes in nitrogen cycling to sustain increases in forest productivity under elevated atmospheric CO2 and contrasting site conditions

    Directory of Open Access Journals (Sweden)

    R. F. Grant

    2013-04-01

    Full Text Available If increases in net primary productivity (NPP caused by rising concentrations of atmospheric CO2 (Ca are to be sustained, key N processes such as soil mineralization, biological fixation, root uptake and plant translocation must be hastened. Simulating the response of these processes to elevated Ca is therefore vital for models used to project the effects of rising Ca on NPP. In this modelling study, hypotheses are proposed for changes in soil mineralization, biological fixation, root uptake and plant translocation with changes in Ca. Algorithms developed from these hypotheses were tested in the ecosystem model ecosys against changes in N and C cycling measured over several years under ambient vs. elevatedCa in Free Air CO2 Enrichment (FACE experiments at the Duke Forest in North Carolina, the Oak Ridge National Laboratory forest in Tennessee, and the USDA research forest in Wisconsin, USA. Simulating more rapid soil N mineralization was found to be vital for modelling sustained increases in NPP measured under elevated vs. ambient Ca at all three FACE sites. This simulation was accomplished by priming decomposition of N-rich humus from increases in microbial biomass generated by increased litterfall modelled under elevated Ca. Simulating more rapid nonsymbiotic N2 fixation, root N uptake and plant N translocation under elevated Ca was found to make much smaller contributions to modelled increases in NPP, although such contributions might be greater over longer periods and under more N-limited conditions than those simulated here. Greater increases in NPP with Ca were also modelled with increased temperature and water stress, and with coniferous vs. deciduous plant functional types. These increases were also associated with changes in N cycling.

  14. Growth hormone (GH) treatment increases serum insulin-like growth factor binding protein-3, bone isoenzyme alkaline phosphatase and forearm bone mineral content in young adults with GH deficiency of childhood onset

    DEFF Research Database (Denmark)

    Juul, A; Pedersen, S A; Sørensen, S

    1994-01-01

    Recent studies have demonstrated that growth hormone (GH)-deficient adults have a markedly decreased bone mineral content compared to healthy adults. However, there are conflicting results regarding the effects of GH treatment on bone mineral content in GH-deficient adults. Therefore, we evaluated...... the effect of GH treatment on a marker of bone formation (bone alkaline phosphatase), hepatic excretory function and distal forearm bone mineral content in GH-deficient adults. Growth hormone was administered subcutaneously in 21 adults (13 males and 8 females) with GH deficiency of childhood onset for 4...... months in a double-blind, placebo-controlled GH trial, while 13 of the patients then received further GH for an additional 14 months. Serum insulin-like growth factor I (IGF-I) increased significantly from 100 to 279 micrograms/l and IGF binding protein-3 (IGFBP-3) from 1930 to 3355 micrograms/l after 4...

  15. Obesity development in neuron-specific lipoprotein lipase deficient mice is not responsive to increased dietary fat content or change in fat composition.

    Science.gov (United States)

    Wang, Hong; Taussig, Matthew D; DiPatrizio, Nicholas V; Bruce, Kimberley; Piomelli, Daniele; Eckel, Robert H

    2016-07-01

    We have previously reported that mice with neuron-specific LPL deficiency (NEXLPL-/-) become obese by 16weeks of age on chow. Moreover, these mice had reduced uptake of triglyceride (TG)-rich lipoprotein-derived fatty acids and lower levels of n-3 long chain polyunsaturated fatty acids (n-3 PUFAs) in the hypothalamus. Here, we asked whether increased dietary fat content or altered dietary composition could modulate obesity development in NEXLPL-/- mice. Male NEXLPL-/- mice and littermate controls (WT) were randomly assigned one of three synthetic diets; a high carbohydrate diet (HC, 10% fat), a high-fat diet (HF, 45% fat), or a HC diet supplemented with n-3 PUFAs (HCn-3, 10% fat, Lovaza, GSK®). After 42weeks of HC feeding, body weight and fat mass were increased in the NEXLPL-/- mice compared to WT. WT mice fed a HF diet displayed typical diet-induced obesity, but weight gain was only marginal in HF-fed NEXLPL-/- mice, with no significant difference in body composition. Dietary n-3 PUFA supplementation did not prevent obesity in NEXLPL-/- mice, but was associated with differential modifications in hypothalamic gene expression and PUFA concentration compared to WT mice. Our findings suggest that neuronal LPL is involved in the regulation of body weight and composition in response to either the change in quantity (HF feeding) or quality (n-3 PUFA-enriched) of dietary fat. The precise role of LPL in lipid sensing in the brain requires further investigation.

  16. CD4+ T-cell deficiency in HIV patients responding to antiretroviral therapy is associated with increased expression of interferon-stimulated genes in CD4+ T cells.

    Science.gov (United States)

    Fernandez, Sonia; Tanaskovic, Sara; Helbig, Karla; Rajasuriar, Reena; Kramski, Marit; Murray, John M; Beard, Michael; Purcell, Damian; Lewin, Sharon R; Price, Patricia; French, Martyn A

    2011-12-15

    Most patients with human immunodeficiency virus (HIV) who remain CD4(+) T-cell deficient on antiretroviral therapy (ART) exhibit marked immune activation. As CD4(+) T-cell activation may be mediated by microbial translocation or interferon-alpha (IFN-α), we examined these factors in HIV patients with good or poor CD4(+) T-cell recovery on long-term ART. Messenger RNA levels for 3 interferon-stimulated genes were increased in CD4(+) T cells of patients with poor CD4(+) T-cell recovery, whereas levels in patients with good recovery did not differ from those in healthy controls. Poor CD4(+) T-cell recovery was also associated with CD4(+) T-cell expression of markers of activation, senescence, and apoptosis, and with increased serum levels of the lipopolysaccharide receptor and soluble CD14, but these were not significantly correlated with expression of the interferon-stimulated genes. Therefore, CD4(+) T-cell recovery may be adversely affected by the effects of IFN-α, which may be amenable to therapeutic intervention.

  17. Ceruloplasmin deficiency reduces levels of iron and BDNF in the cortex and striatum of young mice and increases their vulnerability to stroke.

    Directory of Open Access Journals (Sweden)

    Sarah J Texel

    Full Text Available Ceruloplasmin (Cp is an essential ferroxidase that plays important roles in cellular iron trafficking. Previous findings suggest that the proper regulation and subcellular localization of iron are very important in brain cell function and viability. Brain iron dyshomeostasis is observed during normal aging, as well as in several neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases, coincident with areas more susceptible to insults. Because of their high metabolic demand and electrical excitability, neurons are particularly vulnerable to ischemic injury and death. We therefore set out to look for abnormalities in the brain of young adult mice that lack Cp. We found that iron levels in the striatum and cerebral cortex of these young animals are significantly lower than wild-type (WT controls. Also mRNA levels of the neurotrophin brain derived neurotrophic factor (BDNF, known for its role in maintenance of cell viability, were decreased in these brain areas. Chelator-mediated depletion of iron in cultured neural cells resulted in reduced BDNF expression by a posttranscriptional mechanism, suggesting a causal link between low brain iron levels and reduced BDNF expression. When the mice were subjected to middle cerebral artery occlusion, a model of focal ischemic stroke, we found increased brain damage in Cp-deficient mice compared to WT controls. Our data indicate that lack of Cp increases neuronal susceptibility to ischemic injury by a mechanism that may involve reduced levels of iron and BDNF.

  18. Iron induced nickel deficiency

    Science.gov (United States)

    It is increasingly apparent that economic loss due to nickel (Ni) deficiency likely occurs in horticultural and agronomic crops. While most soils contain sufficient Ni to meet crop requirements, situations of Ni deficiency can arise due to antagonistic interactions with other metals. This study asse...

  19. 5-HTT deficiency affects neuroplasticity and increases stress sensitivity resulting in altered spatial learning performance in the Morris water maze but not in the Barnes maze.

    Directory of Open Access Journals (Sweden)

    Margherita M Karabeg

    Full Text Available The purpose of this study was to evaluate whether spatial hippocampus-dependent learning is affected by the serotonergic system and stress. Therefore, 5-HTT knockout (-/-, heterozygous (+/- and wildtype (+/+ mice were subjected to the Barnes maze (BM and the Morris water maze (WM, the latter being discussed as more aversive. Additionally, immediate early gene (IEG expression, hippocampal adult neurogenesis (aN, and blood plasma corticosterone were analyzed. While the performance of 5-HTT-/- mice in the BM was undistinguishable from both other genotypes, they performed worse in the WM. However, in the course of the repeated WM trials 5-HTT-/- mice advanced to wildtype level. The experience of a single trial of either the WM or the BM resulted in increased plasma corticosterone levels in all genotypes. After several trials 5-HTT-/- mice exhibited higher corticosterone concentrations compared with both other genotypes in both tests. Corticosterone levels were highest in 5-HTT-/- mice tested in the WM indicating greater aversiveness of the WM and a greater stress sensitivity of 5-HTT deficient mice. Quantitative immunohistochemistry in the hippocampus revealed increased cell counts positive for the IEG products cFos and Arc as well as for proliferation marker Ki67 and immature neuron marker NeuroD in 5-HTT-/- mice compared to 5-HTT+/+ mice, irrespective of the test. Most differences were found in the suprapyramidal blade of the dentate gyrus of the septal hippocampus. Ki67-immunohistochemistry revealed a genotype x environment interaction with 5-HTT genotype differences in naïve controls and WM experience exclusively yielding more Ki67-positive cells in 5-HTT+/+ mice. Moreover, in 5-HTT-/- mice we demonstrate that learning performance correlates with the extent of aN. Overall, higher baseline IEG expression and increased an in the hippocampus of 5-HTT-/- mice together with increased stress sensitivity may constitute the neurobiological correlate of

  20. 5-HTT deficiency affects neuroplasticity and increases stress sensitivity resulting in altered spatial learning performance in the Morris water maze but not in the Barnes maze.

    Science.gov (United States)

    Karabeg, Margherita M; Grauthoff, Sandra; Kollert, Sina Y; Weidner, Magdalena; Heiming, Rebecca S; Jansen, Friederike; Popp, Sandy; Kaiser, Sylvia; Lesch, Klaus-Peter; Sachser, Norbert; Schmitt, Angelika G; Lewejohann, Lars

    2013-01-01

    The purpose of this study was to evaluate whether spatial hippocampus-dependent learning is affected by the serotonergic system and stress. Therefore, 5-HTT knockout (-/-), heterozygous (+/-) and wildtype (+/+) mice were subjected to the Barnes maze (BM) and the Morris water maze (WM), the latter being discussed as more aversive. Additionally, immediate early gene (IEG) expression, hippocampal adult neurogenesis (aN), and blood plasma corticosterone were analyzed. While the performance of 5-HTT-/- mice in the BM was undistinguishable from both other genotypes, they performed worse in the WM. However, in the course of the repeated WM trials 5-HTT-/- mice advanced to wildtype level. The experience of a single trial of either the WM or the BM resulted in increased plasma corticosterone levels in all genotypes. After several trials 5-HTT-/- mice exhibited higher corticosterone concentrations compared with both other genotypes in both tests. Corticosterone levels were highest in 5-HTT-/- mice tested in the WM indicating greater aversiveness of the WM and a greater stress sensitivity of 5-HTT deficient mice. Quantitative immunohistochemistry in the hippocampus revealed increased cell counts positive for the IEG products cFos and Arc as well as for proliferation marker Ki67 and immature neuron marker NeuroD in 5-HTT-/- mice compared to 5-HTT+/+ mice, irrespective of the test. Most differences were found in the suprapyramidal blade of the dentate gyrus of the septal hippocampus. Ki67-immunohistochemistry revealed a genotype x environment interaction with 5-HTT genotype differences in naïve controls and WM experience exclusively yielding more Ki67-positive cells in 5-HTT+/+ mice. Moreover, in 5-HTT-/- mice we demonstrate that learning performance correlates with the extent of aN. Overall, higher baseline IEG expression and increased an in the hippocampus of 5-HTT-/- mice together with increased stress sensitivity may constitute the neurobiological correlate of raised

  1. Deficiency of ACE2 in Bone-Marrow-Derived Cells Increases Expression of TNF-α in Adipose Stromal Cells and Augments Glucose Intolerance in Obese C57BL/6 Mice

    Directory of Open Access Journals (Sweden)

    Sean E. Thatcher

    2012-01-01

    Full Text Available Deficiency of ACE2 in macrophages has been suggested to promote the development of an inflammatory M1 macrophage phenotype. We evaluated effects of ACE2 deficiency in bone-marrow-derived stem cells on adipose inflammation and glucose tolerance in C57BL/6 mice fed a high fat (HF diet. ACE2 activity was increased in the stromal vascular fraction (SVF isolated from visceral, but not subcutaneous adipose tissue of HF-fed mice. Deficiency of ACE2 in bone marrow cells significantly increased mRNA abundance of F4/80 and TNF-α in the SVF isolated from visceral adipose tissue of HF-fed chimeric mice, supporting increased presence of inflammatory macrophages in adipose tissue. Moreover, deficiency of ACE2 in bone marrow cells modestly augmented glucose intolerance in HF-fed chimeric mice and increased blood levels of glycosylated hemoglobin. In summary, ACE2 deficiency in bone marrow cells promotes inflammation in adipose tissue and augments obesity-induced glucose intolerance.

  2. Simulation with models of increasing complexity of CO2 emissions and nitrogen mineralisation, after soil application of labelled pig slurry and maize stalks

    Science.gov (United States)

    Bechini, Luca; Marino Gallina, Pietro; Geromel, Gabriele; Corti, Martina; Cavalli, Daniele

    2015-04-01

    High amounts of nitrogen are available per unit area in regions with intensive livestock operations. In swine farms, pig slurries are frequently incorporated in the soil together with maize stalks. Simulation models may help to understand nitrogen dynamics associated with animal manure and crop residue decomposition in the soil, and to support the definition of best management practices. The objective of this work was to test the ability of different models to simulate CO2 emissions and nitrogen mineralisation during a laboratory incubation (under optimal soil water content and constant temperature) of maize stalks (ST) and pig slurry (PS). A loam soil was amended with labelled (15N) or unlabelled maize stalks and pig slurries, in the presence of ammonium sulphate (AS). These treatments were established: unfertilised soil; ST15 + AS + PS; ST + AS15 + PS; and ST + AS + PS15. During 180 days, we measured CO2 emissions; microbial biomass C, N, and 15N; and soil mineral N (SMN and SM-15N). Three models of increasing complexity were calibrated using measured data. The models were two modifications of ICBM 2B/N (Kätterer and Andrén, 2001) and CN-SIM (Petersen et al., 2005). The three models simulated rather accurately the emissions of CO2 throughout the incubation period (Relative Root Mean Squared Error, RRMSE = 8-25). The simplest model (with one pool for ST and one for PS) strongly overestimated SMN immobilisation from day 3 to day 21, both in the treatments with AS15 and PS15 (RRMSE = 27-30%). The other two models represented rather well the dynamics of SMN in the soil (RRMSE = 21-25%), simulating a fast increase of nitrate concentration in the first days, and slower rates of nitrification thereafter. Worse performances were obtained with all models for the simulation of SM-15N in the treatment with ST15 (RRMSE = 64-104%): experimental data showed positive mineralization of stalk-derived N from the beginning of the incubation, while models strongly underestimated

  3. Short branched-chain C6 carboxylic acids result in increased growth, novel 'unnatural' fatty acids and increased membrane fluidity in a Listeria monocytogenes branched-chain fatty acid-deficient mutant.

    Science.gov (United States)

    Sen, Suranjana; Sirobhushanam, Sirisha; Hantak, Michael P; Lawrence, Peter; Brenna, J Thomas; Gatto, Craig; Wilkinson, Brian J

    2015-10-01

    Listeria monocytogenes is a psychrotolerant food borne pathogen, responsible for the high fatality disease listeriosis, and expensive food product recalls. Branched-chain fatty acids (BCFAs) of the membrane play a critical role in providing appropriate membrane fluidity and optimum membrane biophysics. The fatty acid composition of a BCFA-deficient mutant is characterized by high amounts of straight-chain fatty acids and even-numbered iso fatty acids, in contrast to the parent strain where odd-numbered anteiso fatty acids predominate. The presence of 2-methylbutyrate (C5) stimulated growth of the mutant at 37°C and restored growth at 10°C along with the content of odd-numbered anteiso fatty acids. The C6 branched-chain carboxylic acids 2-ethylbutyrate and 2-methylpentanoate also stimulated growth to a similar extent as 2-methylbutyrate. However, 3-methylpentanoate was ineffective in rescuing growth. 2-Ethylbutyrate and 2-methylpentanoate led to novel major fatty acids in the lipid profile of the membrane that were identified as 12-ethyltetradecanoic acid and 12-methylpentadecanoic acid respectively. Membrane anisotropy studies indicated that growth of strain MOR401 in the presence of these precursors increased its membrane fluidity to levels of the wild type. Cells supplemented with 2-methylpentanoate or 2-ethylbutyrate at 10°C shortened the chain length of novel fatty acids, thus showing homeoviscous adaptation. These experiments use the mutant as a tool to modulate the membrane fatty acid compositions through synthetic precursor supplementation, and show how existing enzymes in L. monocytogenes adapt to exhibit non-native activity yielding unique 'unnatural' fatty acid molecules, which nevertheless possess the correct biophysical properties for proper membrane function in the BCFA-deficient mutant.

  4. Planting increases the abundance and structure complexity of soil core functional genes relevant to carbon and nitrogen cycling.

    Science.gov (United States)

    Wang, Feng; Liang, Yuting; Jiang, Yuji; Yang, Yunfeng; Xue, Kai; Xiong, Jinbo; Zhou, Jizhong; Sun, Bo

    2015-09-23

    Plants have an important impact on soil microbial communities and their functions. However, how plants determine the microbial composition and network interactions is still poorly understood. During a four-year field experiment, we investigated the functional gene composition of three types of soils (Phaeozem, Cambisols and Acrisol) under maize planting and bare fallow regimes located in cold temperate, warm temperate and subtropical regions, respectively. The core genes were identified using high-throughput functional gene microarray (GeoChip 3.0), and functional molecular ecological networks (fMENs) were subsequently developed with the random matrix theory (RMT)-based conceptual framework. Our results demonstrated that planting significantly (P soils and 83.5% of microbial alpha-diversity can be explained by the plant factor. Moreover, planting had significant impacts on the microbial community structure and the network interactions of the microbial communities. The calculated network complexity was higher under maize planting than under bare fallow regimes. The increase of the functional genes led to an increase in both soil respiration and nitrification potential with maize planting, indicating that changes in the soil microbial communities and network interactions influenced ecological functioning.

  5. Nitrogen trading tool

    Science.gov (United States)

    The nitrogen cycle is impacted by human activities, including those that increase the use of nitrogen in agricultural systems, and this impact can be seen in effects such as increased nitrate (NO3) levels in groundwater or surface water resources, increased concentration of nitrous oxide (N2O) in th...

  6. Increased [omega]6-Containing Phospholipids and Primary [omega]6 Oxidation Products in the Brain Tissue of Rats on an [omega]3-Deficient Diet

    National Research Council Canada - National Science Library

    Paul H Axelsen; Robert C Murphy; Miki Igarashi; Stanley I Rapoport

    2016-01-01

      Polyunsaturated fatty acyl (PUFA) chains in both the [omega]3 and [omega]6 series are essential for normal animal brain development, and cannot be interconverted to compensate for a dietary deficiency of one or the other...

  7. Activation and increase of radio-sensitive CD11b+ recruited Kupffer cells/macrophages in diet-induced steatohepatitis in FGF5 deficient mice

    Science.gov (United States)

    Nakashima, Hiroyuki; Nakashima, Masahiro; Kinoshita, Manabu; Ikarashi, Masami; Miyazaki, Hiromi; Hanaka, Hiromi; Imaki, Junko; Seki, Shuhji

    2016-01-01

    We have recently reported that Kupffer cells consist of two subsets, radio-resistant resident CD68+ Kupffer cells and radio-sensitive recruited CD11b+ Kupffer cells/macrophages (Mφs). Non-alcoholic steatohepatitis (NASH) is characterized not only by hepatic steatosis but also chronic inflammation and fibrosis. In the present study, we investigated the immunological mechanism of diet-induced steatohepatitis in fibroblast growth factor 5 (FGF5) deficient mice. After consumption of a high fat diet (HFD) for 8 weeks, FGF5 null mice developed severe steatohepatitis and fibrosis resembling human NASH. F4/80+ Mφs which were both CD11b and CD68 positive accumulated in the liver. The production of TNF and FasL indicated that they are the pivotal effectors in this hepatitis. The weak phagocytic activity and lack of CRIg mRNA suggested that they were recruited Mφs. Intermittent exposure to 1 Gy irradiation markedly decreased these Mφs and dramatically inhibited liver inflammation without attenuating steatosis. However, depletion of the resident subset by clodronate liposome (c-lipo) treatment increased the Mφs and tended to exacerbate disease progression. Recruited CD11b+ CD68+ Kupffer cells/Mφs may play an essential role in steatohepatitis and fibrosis in FGF5 null mice fed with a HFD. Recruitment and activation of bone marrow derived Mφs is the key factor to develop steatohepatitis from simple steatosis. PMID:27708340

  8. Iron deficiency anemia at admission for labor and delivery is associated with an increased risk for Cesarean section and adverse maternal and neonatal outcomes.

    Science.gov (United States)

    Drukker, Lior; Hants, Yael; Farkash, Rivka; Ruchlemer, Rosa; Samueloff, Arnon; Grisaru-Granovsky, Sorina

    2015-12-01

    Maternal iron deficiency anemia (IDA) impacts placenta and fetus. We evaluated effects of IDA at admission for delivery on cesarean rates, and adverse maternal and neonatal outcomes. Medical records from Jerusalem (2005-2012) identified women with a live-birth singleton fetus in cephalic presentation of any gestational age and excluded planned cesarean, chronic/gestational diseases identified with anemia. Study population was divided into anemic and non-anemic women using WHO criteria. cesarean rate, and adverse outcomes (maternal: packed cells transfusion, early post-partum hemorrhage, preterm delivery; and neonatal: 5' Apgar Neonatal Intensive Care Unit [NICU] admission, extreme birthweights). Continuous variable analysis and multivariate backward step-wise logistic regression models were prepared with Odds Ratios (OR) and 95% confidence intervals (CI). In all, 96,066 deliveries were registered, of which 75,660 (78.8%) were included. IDA was present in 7,977 women (10.5%). Anemia at birth was significantly associated with cesarean section (OR 1.30; 95%CI, 1.13-1.49, p anemia at delivery is associated with an increased risk for cesarean section and adverse maternal and neonatal outcomes in otherwise healthy women. Monitoring/correction of hemoglobin concentrations even in late pregnancy may prevent these adverse events. © 2015 AABB.

  9. Dietary sodium and iodine in remote Indigenous Australian communities: will salt-reduction strategies increase risk of iodine deficiency? A cross-sectional analysis and simulation study.

    Science.gov (United States)

    McMahon, Emma; Webster, Jacqui; O'Dea, Kerin; Brimblecombe, Julie

    2015-12-30

    Excess salt intake is a global issue. Effective salt-reduction strategies are needed, however, as salt is a vehicle for iodine fortification, these strategies may also reduce iodine intake. This study examines the case of the remote Indigenous Australian population; we employed an innovative, objective method to assess sodium and iodine intakes against requirements and modelled the potential effects of salt-reduction strategies on estimated sodium and iodine intakes. Store-sales data were collected from 20 remote Indigenous community stores in 2012-14 representing the main source of food for 2 years for ~8300 individuals. Estimated average sodium and iodine intakes were compared against recommendations (nutrient reference values weighted to age and gender distribution). Linear programming was employed to simulate potential effects of salt-reduction strategies on estimated sodium and iodine intakes. Estimated average sodium intake was 2770 (range within communities 2410-3450) mg/day, far exceeding the population-weighted upper limit (2060 mg/day). Discretionary (added) salt, bread and processed meat were the biggest contributors providing 46% of all sodium. Estimated average iodine intake was within recommendations at 206 (186-246) μg/day. The following scenarios enabled modelling of estimated average salt intake to within recommendations: 1) 67% reduction in sodium content of bread and discretionary salt intake, 2) 38% reduction in sodium content of all processed foods, 3) 30% reduction in sodium content of all processed foods and discretionary salt intake. In all scenarios, simulated average iodine intakes remained within recommendations. Salt intakes of the remote Indigenous Australian population are far above recommendations, likely contributing to the high prevalence of hypertension and cardiovascular mortality experienced by this population. Salt-reduction strategies could considerably reduce salt intake in this population without increasing risk of iodine

  10. [Effects of increased planting density with reduced nitrogen fertilizer application on rice yield, N use efficiency and greenhouse gas emission in Northeast China].

    Science.gov (United States)

    Zhu, Xiang-cheng; Zhang, Zhen-ping; Zhang, Jun; Deng, Ai-xing; Zhang, Wei-jian

    2016-02-01

    The traditional rice growing practice has to change to save resource and protect environment, and it' s necessary to develop new technology in rice cultivation. Therefore, a two-year field experiment of Japonica rice (Liaoxing 1) was conducted in Northeast China in 2012 and 2013 to investigate the integrated effects of dense planting with less basal nitrogen (N) and unchanged top-dressing N (IR) on rice yield, N use efficiency (NUE) and greenhouse gas emissions. Compared with traditional practice (CK), we increased the rice seedling density by 33.3% and reduced the basal N rate by 20%. The results showed that the average N agronomy efficiency and partial factor productivity were improved by 49.6% (Pefficiency. Generally, proper dense planting with less basal N applicatior could be a good approach for the trade-off between rice yield, NUE and greenhouse gas emission.

  11. THE INCREASE OF SWEET CORN COBS YIELD DUE TO NITROGEN FERTILIZERS AND STRAW MULCHING OF ROW SPACING

    Directory of Open Access Journals (Sweden)

    Sidorenko S. E.

    2015-04-01

    Full Text Available The research about effectiveness of ammonium nitrate with sowing and in phase of corn 5-6 leaves and row spacing cultivation before straw mulching was done in 2011-2013. The scheme of trial included the variants with straw mulching and without it. The variants without fertilizers and with small doses of them on background without mulching gave higher yield of cobs milk maturity then with mulching. But variants with maximum fertilizers (with sowing N30 and in phase of corn 5-6 leaves N30 gave maximum yield of cobs milk maturity 16,4 t/ha that is higher then similar variant without mulching for 1,7 t/ha. These results were confirmed by analysis of characters of growth and development of corn plants, productivity, and economic effectiveness. Therefore, net profit on variant with fertilizers with sowing N30 and additional fertilizing N30 on background of straw mulching increased for 75490 rubles for 1 ha in comparison with similar variant without mulching. The profitability on the best variant was 335 %

  12. Association between an increase in blood urea nitrogen at 24 hours and worse outcomes in acute nonvariceal upper GI bleeding.

    Science.gov (United States)

    Kumar, Navin L; Claggett, Brian L; Cohen, Aaron J; Nayor, Jennifer; Saltzman, John R

    2017-04-02

    An increase in blood urea nitrogen (BUN) at 24 hours is a solitary and significant predictor of mortality in patients with acute pancreatitis, which may predict worse outcomes in the similarly resuscitation-requiring condition of acute nonvariceal upper GI bleeding (UGIB). The aim of our study was to assess whether an increase in BUN at 24 hours is predictive of worse clinical outcomes in acute nonvariceal UGIB. A retrospective cohort study including patients admitted to an academic hospital from 2004 to 2014 was conducted. An increase in BUN was defined as an increase in BUN at 24 hours of hospitalization compared with BUN at presentation. The primary outcome was a composite of inpatient death, inpatient rebleeding, need for surgical or radiologic intervention, or endoscopic reintervention. Associations between BUN change and outcomes were assessed via the Pearson χ(2) test and the Fisher exact test and via logistic regression for adjusted analyses. There were 357 patients included in the analysis with a mean age of 64 years; 54% were men. The mean change in BUN was -10.1 mg/dL (standard deviation, 12.7 mg/dL). Patients with an increased BUN (n = 37 [10%]) were significantly more likely to experience the composite outcome (22% vs 9%, P = .014), including an increased risk of inpatient death (8% vs 1%, P = .004), compared with patients with a decreased or unchanged BUN (n = 320 [90%]). In a logistic regression model adjusting for the AIMS65 score, an increase in BUN was independently associated with an increased risk for the composite outcome (odds ratio, 2.75; P = .026). Increasing BUN at 24 hours likely reflects under resuscitation and is a predictor of worse outcomes in patients with acute nonvariceal UGIB. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  13. Disaccharidase deficiency.

    Science.gov (United States)

    Bayless, T M; Christopher, N L

    1969-02-01

    This review of the literature and current knowledge concerning a nutritional disorder of disaccharidase deficiency discusses the following topics: 1) a description of disorders of disaccharide digestion; 2) some historical perspective on the laboratory and bedside advances in the past 10 years that have helped define a group of these digestive disorders; 3) a classification of conditions causing disaccharide intolerance; and 4) a discussion of some of the specific clinical syndromes emphasizing nutritional consequences of these syndromes. The syndromes described include congenital lactase deficiency, acquired lactase deficiency in teenagers and adults, acquired generalized disaccharidase deficiency secondary to diffuse mucosal damage, acquired lactose intolerance secondary to alterations in the intestinal transit, sucrase-isomaltase deficiencies, and other disease associations connected with lactase deficiency such as colitis.

  14. Deficiency in TNFRSF13B (TACI) expands T-follicular helper and germinal center B cells via increased ICOS-ligand expression but impairs plasma cell survival.

    Science.gov (United States)

    Ou, Xijun; Xu, Shengli; Lam, Kong-Peng

    2012-09-18

    Mutations in TNFRSF13B, better known as transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), contribute to common variable immunodeficiency and autoimmunity in humans. How TACI regulates these two opposing conditions is unclear, however. TACI binds the cytokines BAFF and APRIL, and previous studies using gene KO mice indicated that loss of TACI affected only T-cell-independent antibody responses. Here we demonstrate that Taci(-/-) mice have expanded populations of T follicular helper (T(fh)) and germinal center (GC) B cells in their spleens when immunized with T-cell-dependent antigen. The increased numbers of T(fh) and GC B cells in Taci(-/-) mice are largely a result of up-regulation of inducible costimulator (ICOS) ligand on TACI-deficient B cells, given that ablation of one copy of the Icosl allele restores normal levels of T(fh) and GC B cells in Taci(-/-) mice. Interestingly, despite the presence of increased T(fh) and antigen-specific B cells, immunized Taci(-/-) mice demonstrate defective antigen-specific antibody responses resulting from significantly reduced numbers of antibody-secreting cells (ASCs). This effect is attributed to the failure to down-regulate the proapoptotic molecule BIM in Taci(-/-) plasma cells. Ablation of BIM could rescue ASC formation in Taci(-/-) mice, suggesting that TACI is more important for the survival of plasma cells than for the differentiation of these cells. Thus, our data reveal dual roles for TACI in B-cell terminal differentiation. On one hand, TACI modulates ICOS ligand expression and thereby limits the size of T(fh) and GC B-cell compartments and prevents autoimmunity. On the other hand, it regulates the survival of ASCs and plays an important role in humoral immunity.

  15. Impaired glucose metabolism is a risk factor for increased thyroid volume and nodule prevalence in a mild-to-moderate iodine deficient area.

    Science.gov (United States)

    Anil, Cuneyd; Akkurt, Aysen; Ayturk, Semra; Kut, Altug; Gursoy, Alptekin

    2013-07-01

    Insulin resistance (IR) is a key factor involved in the pathogenesis of impaired glucose metabolism. IR is associated with increased thyroid volume and nodule prevalence in patients with metabolic syndrome. Data on the association of thyroid morphology and abnormal glucose metabolism are limited. This prospective study was carried out to evaluate thyroid volume and nodule prevalence in patients with pre-diabetes and type 2 diabetes mellitus (DM) in a mild-to-moderate iodine deficient area. Data were gathered on all newly diagnosed patients with pre-diabetes and type 2 diabetes mellitus between May 2008 and February 2010. 156 patients with pre-diabetes and 123 patients with type 2 DM were randomly matched for age, gender, and smoking habits with 114 subjects with normal glucose metabolism. Serum thyroid-stimulating hormone (TSH) and thyroid ultrasonography was performed in all participants. Mean TSH level in the diabetes group (1.9±0.9 mIU/L) was higher than in the control group (1.4±0.8 mIU/L) and the pre-diabetes group (1.5±0.8 mIU/L) (P<0.0001 for both). Mean thyroid volume was higher in the pre-diabetes (18.2±9.2mL) and diabetes (20.0±8.2mL) groups than in controls (11.4±3.8mL) (P<0.0001 for both). Percentage of patients with thyroid nodules was also higher in the pre-diabetes (51.3%) and diabetes groups (61.8%) than in controls (23.7%) (P<0.0001 for both). The results suggest that patients with impaired glucose metabolism have significantly increased thyroid volume and nodule prevalence. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Increased gamma- and decreased delta-oscillations in a mouse deficient for a potassium channel expressed in fast-spiking interneurons.

    Science.gov (United States)

    Joho, R H; Ho, C S; Marks, G A

    1999-10-01

    Kv3.1 is a voltage-gated, fast activating/deactivating potassium (K(+)) channel with a high-threshold of activation and a large unit conductance. Kv3.1 K(+) channels are expressed in fast-spiking, parvalbumin-containing interneurons in cortex, hippocampus, striatum, the thalamic reticular nucleus (TRN), and in several nuclei of the brain stem. A high density of Kv3.1 channels contributes to short-duration action potentials, fast afterhyperpolarizations, and brief refractory periods enhancing the capability in these neurons for high-frequency firing. Kv3