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Sample records for sulfate starvation response

  1. The SULTR gene family in maize (Zea mays L.): Gene cloning and expression analyses under sulfate starvation and abiotic stress.

    Science.gov (United States)

    Huang, Qin; Wang, Meiping; Xia, Zongliang

    2018-01-01

    Sulfur is an essential macronutrient required for plant growth, development and stress responses. The family of sulfate transporters (SULTRs) mediates the uptake and translocation of sulfate in higher plants. However, basic knowledge of the SULTR gene family in maize (Zea mays L.) is scarce. In this study, a genome-wide bioinformatic analysis of SULTR genes in maize was conducted, and the developmental expression patterns of the genes and their responses to sulfate starvation and abiotic stress were further investigated. The ZmSULTR family includes eight putative members in the maize genome and is clustered into four groups in the phylogenetic tree. These genes displayed differential expression patterns in various organs of maize. For example, expression of ZmSULTR1;1 and ZmSULTR4;1 was high in roots, and transcript levels of ZmSULTR3;1 and ZmSULTR3;3 were high in shoots. Expression of ZmSULTR1;2, ZmSULTR2;1, ZmSULTR3;3, and ZmSULTR4;1 was high in flowers. Also, these eight genes showed differential responses to sulfate deprivation in roots and shoots of maize seedlings. Transcript levels of ZmSULTR1;1, ZmSULTR1;2, and ZmSULTR3;4 were significantly increased in roots during 12-day-sulfate starvation stress, while ZmSULTR3;3 and ZmSULTR3;5 only showed an early response pattern in shoots. In addition, dynamic transcriptional changes determined via qPCR revealed differential expression profiles of these eight ZmSULTR genes in response to environmental stresses such as salt, drought, and heat stresses. Notably, all the genes, except for ZmSULTR3;3, were induced by drought and heat stresses. However, a few genes were induced by salt stress. Physiological determination showed that two important thiol-containing compounds, cysteine and glutathione, increased significantly under these abiotic stresses. The results suggest that members of the SULTR family might function in adaptations to sulfur deficiency stress and adverse growing environments. This study will lay a

  2. Larval starvation improves metabolic response to adult starvation in honey bees (Apis mellifera L.).

    Science.gov (United States)

    Wang, Ying; Campbell, Jacob B; Kaftanoglu, Osman; Page, Robert E; Amdam, Gro V; Harrison, Jon F

    2016-04-01

    Environmental changes during development have long-term effects on adult phenotypes in diverse organisms. Some of the effects play important roles in helping organisms adapt to different environments, such as insect polymorphism. Others, especially those resulting from an adverse developmental environment, have a negative effect on adult health and fitness. However, recent studies have shown that those phenotypes influenced by early environmental adversity have adaptive value under certain (anticipatory) conditions that are similar to the developmental environment, though evidence is mostly from morphological and behavioral observations and it is still rare at physiological and molecular levels. In the companion study, we applied a short-term starvation treatment to fifth instar honey bee larvae and measured changes in adult morphology, starvation resistance, hormonal and metabolic physiology and gene expression. Our results suggest that honey bees can adaptively respond to the predicted nutritional stress. In the present study, we further hypothesized that developmental starvation specifically improves the metabolic response of adult bees to starvation instead of globally affecting metabolism under well-fed conditions. Here, we produced adult honey bees that had experienced a short-term larval starvation, then we starved them for 12 h and monitored metabolic rate, blood sugar concentrations and metabolic reserves. We found that the bees that experienced larval starvation were able to shift to other fuels faster and better maintain stable blood sugar levels during starvation. However, developmental nutritional stress did not change metabolic rates or blood sugar levels in adult bees under normal conditions. Overall, our study provides further evidence that early larval starvation specifically improves the metabolic responses to adult starvation in honey bees. © 2016. Published by The Company of Biologists Ltd.

  3. Regulation of phosphate starvation responses in higher plants.

    Science.gov (United States)

    Yang, Xiao Juan; Finnegan, Patrick M

    2010-04-01

    Phosphorus (P) is often a limiting mineral nutrient for plant growth. Many soils worldwide are deficient in soluble inorganic phosphate (P(i)), the form of P most readily absorbed and utilized by plants. A network of elaborate developmental and biochemical adaptations has evolved in plants to enhance P(i) acquisition and avoid starvation. Controlling the deployment of adaptations used by plants to avoid P(i) starvation requires a sophisticated sensing and regulatory system that can integrate external and internal information regarding P(i) availability. In this review, the current knowledge of the regulatory mechanisms that control P(i) starvation responses and the local and long-distance signals that may trigger P(i) starvation responses are discussed. Uncharacterized mutants that have P(i)-related phenotypes and their potential to give us additional insights into regulatory pathways and P(i) starvation-induced signalling are also highlighted and assessed. An impressive list of factors that regulate P(i) starvation responses is now available, as is a good deal of knowledge regarding the local and long-distance signals that allow a plant to sense and respond to P(i) availability. However, we are only beginning to understand how these factors and signals are integrated with one another in a regulatory web able to control the range of responses demonstrated by plants grown in low P(i) environments. Much more knowledge is needed in this agronomically important area before real gains can be made in improving P(i) acquisition in crop plants.

  4. Species-specific roles of sulfolipid metabolism in acclimation of photosynthetic microbes to sulfur-starvation stress.

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    Norihiro Sato

    Full Text Available Photosynthetic organisms utilize sulfate for the synthesis of sulfur-compounds including proteins and a sulfolipid, sulfoquinovosyl diacylglycerol. Upon ambient deficiency in sulfate, cells of a green alga, Chlamydomonas reinhardtii, degrade the chloroplast membrane sulfolipid to ensure an intracellular-sulfur source for necessary protein synthesis. Here, the effects of sulfate-starvation on the sulfolipid stability were investigated in another green alga, Chlorella kessleri, and two cyanobacteria, Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942. The results showed that sulfolipid degradation was induced only in C. kessleri, raising the possibility that this degradation ability was obtained not by cyanobacteria, but by eukaryotic algae during the evolution of photosynthetic organisms. Meanwhile, Synechococcus disruptants concerning sqdB and sqdX genes, which are involved in successive reactions in the sulfolipid synthesis pathway, were respectively characterized in cellular response to sulfate-starvation. Phycobilisome degradation intrinsic to Synechococcus, but not to Synechocystis, and cell growth under sulfate-starved conditions were repressed in the sqdB and sqdX disruptants, respectively, relative to in the wild type. Their distinct phenotypes, despite the common loss of the sulfolipid, inferred specific roles of sqdB and sqdX. This study demonstrated that sulfolipid metabolism might have been developed to enable species- or cyanobacterial-strain dependent processes for acclimation to sulfate-starvation.

  5. Somatic insulin signaling regulates a germline starvation response in Drosophila egg chambers

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    Burn, K. Mahala; Shimada, Yuko; Ayers, Kathleen; Lu, Feiyue; Hudson, Andrew M.; Cooley, Lynn

    2014-01-01

    Egg chambers from starved Drosophila females contain large aggregates of processing (P) bodies and cortically enriched microtubules. As this response to starvation is rapidly reversed upon re-feeding females or culturing egg chambers with exogenous bovine insulin, we examined the role of endogenous insulin signaling in mediating the starvation response. We found that systemic Drosophila insulin-like peptides (dILPs) activate the insulin pathway in follicle cells, which then regulate both microtubule and P body organization in the underlying germline cells. This organization is modulated by the motor proteins Dynein and Kinesin. Dynein activity is required for microtubule and P body organization during starvation, while Kinesin activity is required during nutrient-rich conditions. Blocking the ability of egg chambers to form P body aggregates in response to starvation correlated with reduced progeny survival. These data suggest a potential mechanism to maximize fecundity even during periods of poor nutrient availability, by mounting a protective response in immature egg chambers. PMID:25481758

  6. Transcriptome response to nitrogen starvation in rice

    Indian Academy of Sciences (India)

    N starvation induced or suppressed transcription of 3518 genes, representing 10.88% of the genome. These changes, mostly transient, affected various cellular metabolic pathways, including stress response, primary and secondary metabolism, molecular transport, regulatory process and organismal development. 462 or ...

  7. A central regulatory system largely controls transcriptional activation and repression responses to phosphate starvation in Arabidopsis.

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    Regla Bustos

    2010-09-01

    Full Text Available Plants respond to different stresses by inducing or repressing transcription of partially overlapping sets of genes. In Arabidopsis, the PHR1 transcription factor (TF has an important role in the control of phosphate (Pi starvation stress responses. Using transcriptomic analysis of Pi starvation in phr1, and phr1 phr1-like (phl1 mutants and in wild type plants, we show that PHR1 in conjunction with PHL1 controls most transcriptional activation and repression responses to phosphate starvation, regardless of the Pi starvation specificity of these responses. Induced genes are enriched in PHR1 binding sequences (P1BS in their promoters, whereas repressed genes do not show such enrichment, suggesting that PHR1(-like control of transcriptional repression responses is indirect. In agreement with this, transcriptomic analysis of a transgenic plant expressing PHR1 fused to the hormone ligand domain of the glucocorticoid receptor showed that PHR1 direct targets (i.e., displaying altered expression after GR:PHR1 activation by dexamethasone in the presence of cycloheximide corresponded largely to Pi starvation-induced genes that are highly enriched in P1BS. A minimal promoter containing a multimerised P1BS recapitulates Pi starvation-specific responsiveness. Likewise, mutation of P1BS in the promoter of two Pi starvation-responsive genes impaired their responsiveness to Pi starvation, but not to other stress types. Phylogenetic footprinting confirmed the importance of P1BS and PHR1 in Pi starvation responsiveness and indicated that P1BS acts in concert with other cis motifs. All together, our data show that PHR1 and PHL1 are partially redundant TF acting as central integrators of Pi starvation responses, both specific and generic. In addition, they indicate that transcriptional repression responses are an integral part of adaptive responses to stress.

  8. Multi-omics Analyses of Starvation Responses Reveal a Central Role for Lipoprotein Metabolism in Acute Starvation Survival in C. elegans

    DEFF Research Database (Denmark)

    Harvald, Eva Bang; Sprenger, Richard R; Dall, Kathrine Brændgaard

    2017-01-01

    Starvation causes comprehensive metabolic changes, which are still not fully understood. Here, we used quantitative proteomics and RNA sequencing to examine the temporal starvation responses in wild-type Caenorhabditis elegans and animals lacking the transcription factor HLH-30. Our findings show...

  9. The oogenic germline starvation response in C. elegans.

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    Hannah S Seidel

    Full Text Available Many animals alter their reproductive strategies in response to environmental stress. Here we have investigated how L4 hermaphrodites of Caenorhabditis elegans respond to starvation. To induce starvation, we removed food at 2 h intervals from very early- to very late-stage L4 animals. The starved L4s molted into adulthood, initiated oogenesis, and began producing embryos; however, all three processes were severely delayed, and embryo viability was reduced. Most animals died via 'bagging,' because egg-laying was inhibited, and embryos hatched in utero, consuming their parent hermaphrodites from within. Some animals, however, avoided bagging and survived long term. Long-term survival did not rely on embryonic arrest but instead upon the failure of some animals to produce viable progeny during starvation. Regardless of the bagging fate, starved animals showed two major changes in germline morphology: All oogenic germlines were dramatically reduced in size, and these germlines formed only a single oocyte at a time, separated from the remainder of the germline by a tight constriction. Both changes in germline morphology were reversible: Upon re-feeding, the shrunken germlines regenerated, and multiple oocytes formed concurrently. The capacity for germline regeneration upon re-feeding was not limited to the small subset of animals that normally survive starvation: When bagging was prevented ectopically by par-2 RNAi, virtually all germlines still regenerated. In addition, germline shrinkage strongly correlated with oogenesis, suggesting that during starvation, germline shrinkage may provide material for oocyte production. Finally, germline shrinkage and regeneration did not depend upon crowding. Our study confirms previous findings that starvation uncouples germ cell proliferation from germline stem cell maintenance. Our study also suggests that when nutrients are limited, hermaphrodites scavenge material from their germlines to reproduce. We discuss

  10. The response and recovery of the Arabidopsis thaliana transcriptome to phosphate starvation

    KAUST Repository

    Woo, Jongchan

    2012-05-03

    Background: Over application of phosphate fertilizers in modern agriculture contaminates waterways and disrupts natural ecosystems. Nevertheless, this is a common practice among farmers, especially in developing countries as abundant fertilizers are believed to boost crop yields. The study of plant phosphate metabolism and its underlying genetic pathways is key to discovering methods of efficient fertilizer usage. The work presented here describes a genome-wide resource on the molecular dynamics underpinning the response and recovery in roots and shoots of Arabidopsis thaliana to phosphate-starvation.Results: Genome-wide profiling by micro- and tiling-arrays (accessible from GEO: GSE34004) revealed minimal overlap between root and shoot transcriptomes suggesting two independent phosphate-starvation regulons. Novel gene expression patterns were detected for over 1000 candidates and were classified as either initial, persistent, or latent responders. Comparative analysis to AtGenExpress identified cohorts of genes co-regulated across multiple stimuli. The hormone ABA displayed a dominant role in regulating many phosphate-responsive candidates. Analysis of co-regulation enabled the determination of specific versus generic members of closely related gene families with respect to phosphate-starvation. Thus, among others, we showed that PHR1-regulated members of closely related phosphate-responsive families (PHT1;1, PHT1;7-9, SPX1-3, and PHO1;H1) display greater specificity to phosphate-starvation than their more generic counterparts. Conclusion: Our results uncover much larger, staged responses to phosphate-starvation than previously described. To our knowledge, this work describes the most complete genome-wide data on plant nutrient stress to-date. 2012 Woo et al.; licensee BioMed Central Ltd.

  11. Gene expression patterns of sulfur starvation in Synechocystis sp. PCC 6803

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    Pendse Ninad D

    2008-07-01

    Full Text Available Abstract Background The unicellular cyanobacterium Synechocystis sp. PCC 6803 is a model microbe for studying biochemistry, genetics and molecular biology of photobiological processes. Importance of this bacterium in basic and applied research calls for a systematic, genome-wide description of its transcriptional regulatory capacity. Characteristic transcriptional responses to changes in the growth environment are expected to provide a scaffold for describing the Synechocystis transcriptional regulatory network as well as efficient means for functional annotation of genes in the genome. Results We designed, validated and used Synechocystis genome-wide oligonucleotide (70-mer microarray (representing 96.7% of all chromosomal ORFs annotated at the time of the beginning of this project to study transcriptional activity of the cyanobacterial genome in response to sulfur (S starvation. The microarray data were verified by quantitative RT-PCR. We made five main observations: 1 Transcriptional changes upon sulfate starvation were relatively moderate, but significant and consistent with growth kinetics; 2 S acquisition genes encoding for a high-affinity sulfate transporter were significantly induced, while decreased transcription of genes for phycobilisome, photosystems I and II, cytochrome b6/f, and ATP synthase indicated reduced light-harvesting and photosynthetic activity; 3 S starvation elicited transcriptional responses associated with general growth arrest and stress; 4 A large number of genes regulated by S availability encode hypothetical proteins or proteins of unknown function; 5 Hydrogenase structural and maturation accessory genes were not identified as differentially expressed, even though increased hydrogen evolution was observed. Conclusion The expression profiles recorded by using this oligonucleotide-based microarray platform revealed that during transition from the condition of plentiful S to S starvation, Synechocystis undergoes

  12. The combination of energy-dependent internal adaptation mechanisms and external factors enables Listeria monocytogenes to express a strong starvation survival response during multiple-nutrient starvation.

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    Lungu, Bwalya; Saldivar, Joshua C; Story, Robert; Ricke, Steven C; Johnson, Michael G

    2010-05-01

    The goal of this study was to characterize the starvation survival response (SSR) of a wild-type Listeria monocytogenes 10403S and an isogenic DeltasigB mutant strain during multiple-nutrient starvation conditions over 28 days. This study examined the effects of inhibitors of protein synthesis, the proton motive force, substrate level phosphorylation, and oxidative phosphorylation on the SSR of L. monocytogenes 10403S and a DeltasigB mutant during multiple-nutrient starvation. The effects of starvation buffer changes on viability were also examined. During multiple-nutrient starvation, both strains expressed a strong SSR, suggesting that L. monocytogenes possesses SigB-independent mechanism(s) for survival during multiple-nutrient starvation. Neither strain was able to express an SSR following starvation buffer changes, indicating that the nutrients/factors present in the starvation buffer could be a source of energy for cell maintenance and survival. Neither the wild-type nor the DeltasigB mutant strain was able to elicit an SSR when exposed to the protein synthesis inhibitor chloramphenicol within the first 4 h of starvation. However, both strains expressed an SSR when exposed to chloramphenicol after 6 h or more of starvation, suggesting that the majority of proteins required to elicit an effective SSR in L. monocytogenes are likely produced somewhere between 4 and 6 h of starvation. The varying SSRs of both strains to the different metabolic inhibitors under aerobic or anaerobic conditions suggested that (1) energy derived from the proton motive force is important for an effective SSR, (2) L. monocytogenes utilizes an anaerobic electron transport during multiple-nutrient starvation conditions, and (3) the glycolytic pathway is an important energy source during multiple-nutrient starvation when oxygen is available, and less important under anaerobic conditions. Collectively, the data suggest that the combination of energy-dependent internal adaptation mechanisms

  13. Starvation and Imidacloprid Exposure Influence Immune Response by Anoplophora glabripennis (Coleoptera: Cerambycidae) to a Fungal Pathogen.

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    Fisher, Joanna J; Castrillo, Louela A; Donzelli, Bruno G G; Hajek, Ann E

    2017-08-01

    In several insect systems, fungal entomopathogens synergize with neonicotinoid insecticides which results in accelerated host death. Using the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), an invasive woodborer inadvertently introduced into North America and Europe, we investigated potential mechanisms in the synergy between the entomopathogenic fungus Metarhizium brunneum Petch and the insecticide imidacloprid. A potential mechanism underlying this synergy could be imidacloprid's ability to prevent feeding shortly after administration. We investigated whether starvation would have an impact similar to imidacloprid exposure on the mortality of fungal-inoculated beetles. Using real-time PCR to quantify fungal load in inoculated beetles, we determined how starvation and pesticide exposure impacted beetles' ability to tolerate or resist a fungal infection. The effect of starvation and pesticide exposure on the encapsulation and melanization immune responses of the beetles was also quantified. Starvation had a similar impact on the survival of M. brunneum-inoculated beetles compared to imidacloprid exposure. The synergy, however, was not completely due to starvation, as imidacloprid reduced the beetles' melanotic encapsulation response and capsule area, while starvation did not significantly reduce these immune responses. Our results suggest that there are multiple interacting mechanisms involved in the synergy between M. brunneum and imidacloprid. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Overexpression of GbWRKY1 positively regulates the Pi starvation response by alteration of auxin sensitivity in Arabidopsis.

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    Xu, Li; Jin, Li; Long, Lu; Liu, Linlin; He, Xin; Gao, Wei; Zhu, Longfu; Zhang, Xianlong

    2012-12-01

    Overexpression of a cotton defense-related gene GbWRKY1 in Arabidopsis resulted in modification of the root system by enhanced auxin sensitivity to positively regulate the Pi starvation response. GbWRKY1 was a cloned WRKY transcription factor from Gossypium barbadense, which was firstly identified as a defense-related gene and showed moderate similarity with AtWRKY75 from Arabidopsis thaliana. Overexpression of GbWRKY1 in Arabidopsis resulted in attenuated Pi starvation stress symptoms, including reduced accumulation of anthocyanin and impaired density of lateral roots (LR) in low Pi stress. The study also indicated that overexpression of GbWRKY1 caused plants constitutively exhibited Pi starvation response including increased development of LR, relatively high level of total P and Pi, high expression level of some high-affinity Pi transporters and phosphatases as well as enhanced accumulation of acid phosphatases activity during Pi-sufficient. It was speculated that GbWRKY1 may act as a positive regulator in the Pi starvation response as well as AtWRKY75. GbWRKY1 probably involves in the modulation of Pi homeostasis and participates in the Pi allocation and remobilization but do not accumulate more Pi in Pi-deficient condition, which was different from the fact that AtWRKY75 influenced the Pi status of the plant during Pi deprivation by increasing root surface area and accumulation of more Pi. Otherwise, further study suggested that the overexpression plants were more sensitive to auxin than wild-type and GbWRKY1 may partly influence the LPR1-dependent (low phosphate response 1) Pi starvation signaling pathway and was putatively independent of SUMO E3 ligase SIZ1 and PHR1 (phosphate starvation response 1) in response to Pi starvation.

  15. The carbon starvation response of Aspergillus niger during submerged cultivation: Insights from the transcriptome and secretome

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    Nitsche Benjamin M

    2012-08-01

    Full Text Available Abstract Background Filamentous fungi are confronted with changes and limitations of their carbon source during growth in their natural habitats and during industrial applications. To survive life-threatening starvation conditions, carbon from endogenous resources becomes mobilized to fuel maintenance and self-propagation. Key to understand the underlying cellular processes is the system-wide analysis of fungal starvation responses in a temporal and spatial resolution. The knowledge deduced is important for the development of optimized industrial production processes. Results This study describes the physiological, morphological and genome-wide transcriptional changes caused by prolonged carbon starvation during submerged batch cultivation of the filamentous fungus Aspergillus niger. Bioreactor cultivation supported highly reproducible growth conditions and monitoring of physiological parameters. Changes in hyphal growth and morphology were analyzed at distinct cultivation phases using automated image analysis. The Affymetrix GeneChip platform was used to establish genome-wide transcriptional profiles for three selected time points during prolonged carbon starvation. Compared to the exponential growth transcriptome, about 50% (7,292 of all genes displayed differential gene expression during at least one of the starvation time points. Enrichment analysis of Gene Ontology, Pfam domain and KEGG pathway annotations uncovered autophagy and asexual reproduction as major global transcriptional trends. Induced transcription of genes encoding hydrolytic enzymes was accompanied by increased secretion of hydrolases including chitinases, glucanases, proteases and phospholipases as identified by mass spectrometry. Conclusions This study is the first system-wide analysis of the carbon starvation response in a filamentous fungus. Morphological, transcriptomic and secretomic analyses identified key events important for fungal survival and their chronology. The

  16. FGF21 and the late adaptive response to starvation in humans.

    Science.gov (United States)

    Fazeli, Pouneh K; Lun, Mingyue; Kim, Soo M; Bredella, Miriam A; Wright, Spenser; Zhang, Yang; Lee, Hang; Catana, Ciprian; Klibanski, Anne; Patwari, Parth; Steinhauser, Matthew L

    2015-11-03

    In mice, FGF21 is rapidly induced by fasting, mediates critical aspects of the adaptive starvation response, and displays a number of positive metabolic properties when administered pharmacologically. In humans, however, fasting does not consistently increase FGF21, suggesting a possible evolutionary divergence in FGF21 function. Moreover, many key aspects of FGF21 function in mice have been identified in the context of transgenic overexpression or administration of supraphysiologic doses, rather than in a physiologic setting. Here, we explored the dynamics and function of FGF21 in human volunteers during a 10-day fast. Unlike mice, which show an increase in circulating FGF21 after only 6 hours, human subjects did not have a notable surge in FGF21 until 7 to 10 days of fasting. Moreover, we determined that FGF21 induction was associated with decreased thermogenesis and adiponectin, an observation that directly contrasts with previous reports based on supraphysiologic dosing. Additionally, FGF21 levels increased after ketone induction, demonstrating that endogenous FGF21 does not drive starvation-mediated ketogenesis in humans. Instead, a longitudinal analysis of biologically relevant variables identified serum transaminases--markers of tissue breakdown--as predictors of FGF21. These data establish FGF21 as a fasting-induced hormone in humans and indicate that FGF21 contributes to the late stages of adaptive starvation, when it may regulate the utilization of fuel derived from tissue breakdown.

  17. Antioxidative and immunological responses in the haemolymph of wolf spider Xerolycosa nemoralis (Lycosidae) exposed to starvation and dimethoate

    International Nuclear Information System (INIS)

    Stalmach, Monika; Wilczek, Grażyna; Homa, Joanna; Szulinska, Elżbieta

    2015-01-01

    The aim of this study was to assess the intensity of enzymatic antioxidative parameters [catalase (CAT), glutathione peroxidase (GSTPx), glutathione reductase (GR), total antioxidant capacity (TAC)] and percentage of high granularity cells as well as low to medium granularity cells in haemolymph of wolf spiders Xerolycosa nemoralis exposed to starvation and dimethoate under laboratory conditions. Only in starved males, haemolymph included a lower percentage of high granularity cells, accompanied by high activity of CAT and GSTPx, than in the control. Exposure of males to dimethoate increased CAT activity, after single application, and significantly enhanced GR activity, after five-time application. In females, five-time contact with dimethoate elevated the percentage of high granularity cells. As in comparison to females, male X. nemoralis were more sensitive to the applied stressing factors, it may be concluded that in natural conditions both food deficiency and chemical stress may diminish the immune response of their organisms. - Highlights: • Starvation of males diminishes their immunological potential. • Females, compared with males, are less sensitive to starvation and dimethoate. • Antioxidative responses are stronger in starvation than after dimethoate intoxication. - The level of antioxidative response and quantitative changes of haemocytes in the haemolymph of wolf spider Xerolycosa nemoralis (Lycosidae) depend on the stressor and gender.

  18. Genome-wide transcriptional responses to carbon starvation in nongrowing Lactococcus lactis

    NARCIS (Netherlands)

    Ercan, O.; Wels, M.; Smid, E.J.; Kleerebezem, M.

    2015-01-01

    This paper describes the transcriptional adaptations of nongrowing, retentostat cultures of Lactococcus lactis to starvation. Near-zero-growth cultures (µ = 0.0001 h-1) obtained by extended retentostat cultivation were exposed to starvation by termination of the medium supply for 24 h, followed by a

  19. Increase of chromium tolerance in Scenedesmus acutus after sulfur starvation: Chromium uptake and compartmentalization in two strains with different sensitivities to Cr(VI).

    Science.gov (United States)

    Marieschi, M; Gorbi, G; Zanni, C; Sardella, A; Torelli, A

    2015-10-01

    In photosynthetic organisms sulfate constitutes the main sulfur source for the biosynthesis of GSH and its precursor Cys. Hence, sulfur availability can modulate the capacity to cope with environmental stresses, a phenomenon known as SIR/SED (Sulfur Induced Resistance or Sulfur Enhanced Defence). Since chromate may compete for sulfate transport into the cells, in this study chromium accumulation and tolerance were investigated in relation to sulfur availability in two strains of the unicellular green alga Scenedesmus acutus with different Cr-sensitivities. Paradoxically, sulfur deprivation has been demonstrated to induce a transient increase of Cr-tolerance in both strains. Sulfur deprivation is known to enhance the sulfate uptake/assimilation pathway leading to important consequences on Cr-tolerance: (i) reduced chromate uptake due to the induction of high affinity sulfate transporters (ii) higher production of cysteine and GSH which can play a role both through the formation of unsoluble complexes and their sequestration in inert compartments. To investigate the role of the above mentioned mechanisms, Cr accumulation in total cells and in different cell compartments (cell wall, membranes, soluble and miscellaneous fractions) was analyzed in both sulfur-starved and unstarved cells. Both strains mainly accumulated chromium in the soluble fraction, but the uptake was higher in the wild-type. In this type a short period of sulfur starvation before Cr(VI) treatment lowered chromium accumulation to the level observed in the unstarved Cr-tolerant strain, in which Cr uptake seems instead less influenced by S-starvation, since no significant decrease was observed. The increase in Cr-tolerance following S-starvation seems thus to rely on different mechanisms in the two strains, suggesting the induction of a mechanism constitutively active in the Cr-tolerant strain, maybe a high affinity sulfate transporter also in the wild-type. Changes observed in the cell wall and

  20. Transcriptional and Proteomic Profiling of Aspergillus flavipes in Response to Sulfur Starvation.

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    El-Sayed, Ashraf S A; Yassin, Marwa A; Ali, Gul Shad

    2015-01-01

    Aspergillus flavipes has received considerable interest due to its potential to produce therapeutic enzymes involved in sulfur amino acid metabolism. In natural habitats, A. flavipes survives under sulfur limitations by mobilizing endogenous and exogenous sulfur to operate diverse cellular processes. Sulfur limitation affects virulence and pathogenicity, and modulates proteome of sulfur assimilating enzymes of several fungi. However, there are no previous reports aimed at exploring effects of sulfur limitation on the regulation of A. flavipes sulfur metabolism enzymes at the transcriptional, post-transcriptional and proteomic levels. In this report, we show that sulfur limitation affects morphological and physiological responses of A. flavipes. Transcription and enzymatic activities of several key sulfur metabolism genes, ATP-sulfurylase, sulfite reductase, methionine permease, cysteine synthase, cystathionine β- and γ-lyase, glutathione reductase and glutathione peroxidase were increased under sulfur starvation conditions. A 50 kDa protein band was strongly induced by sulfur starvation, and the proteomic analyses of this protein band using LC-MS/MS revealed similarity to many proteins involved in the sulfur metabolism pathway.

  1. Functional Disruption of a Chloroplast Pseudouridine Synthase Desensitizes Arabidopsis Plants to Phosphate Starvation

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    Shan Lu

    2017-08-01

    Full Text Available Phosphate (Pi deficiency is a common nutritional stress of plants in both agricultural and natural ecosystems. Plants respond to Pi starvation in the environment by triggering a suite of biochemical, physiological, and developmental changes that increase survival and growth. The key factors that determine plant sensitivity to Pi starvation, however, are unclear. In this research, we identified an Arabidopsis mutant, dps1, with greatly reduced sensitivity to Pi starvation. The dps1 phenotypes are caused by a mutation in the previously characterized SVR1 (SUPPRESSION OF VARIAGATION 1 gene, which encodes a chloroplast-localized pseudouridine synthase. The mutation of SVR1 results in defects in chloroplast rRNA biogenesis, which subsequently reduces chloroplast translation. Another mutant, rps5, which contains a mutation in the chloroplast ribosomal protein RPS5 and has reduced chloroplast translation, also displayed decreased sensitivity to Pi starvation. Furthermore, wild type plants treated with lincomycin, a chemical inhibitor of chloroplast translation, showed similar growth phenotypes and Pi starvation responses as dps1 and rps5. These results suggest that impaired chloroplast translation desensitizes plants to Pi starvation. Combined with previously published results showing that enhanced leaf photosynthesis augments plant responses to Pi starvation, we propose that the decrease in responses to Pi starvation in dps1, rps5, and lincomycin-treated plants is due to their reduced demand for Pi input from the environment.

  2. Transcriptome analysis of the sulfate deficiency response in the marine microalga Emiliania huxleyi.

    Science.gov (United States)

    Bochenek, Michal; Etherington, Graham J; Koprivova, Anna; Mugford, Sam T; Bell, Thomas G; Malin, Gill; Kopriva, Stanislav

    2013-08-01

    The response to sulfate deficiency of plants and freshwater green algae has been extensively analysed by system biology approaches. By contrast, seawater sulfate concentration is high and very little is known about the sulfur metabolism of marine organisms. Here, we used a combination of metabolite analysis and transcriptomics to analyse the response of the marine microalga Emiliania huxleyi as it acclimated to sulfate limitation. Lowering sulfate availability in artificial seawater from 25 to 5 mM resulted in significant reduction in growth and intracellular concentrations of dimethylsulfoniopropionate and glutathione. Sulfate-limited E. huxleyi cells showed increased sulfate uptake but sulfate reduction to sulfite did not seem to be regulated. Sulfate limitation in E. huxleyi affected expression of 1718 genes. The vast majority of these genes were upregulated, including genes involved in carbohydrate and lipid metabolism, and genes involved in the general stress response. The acclimation response of E. huxleyi to sulfate deficiency shows several similarities to the well-described responses of Arabidopsis and Chlamydomonas, but also has many unique features. This dataset shows that even though E. huxleyi is adapted to constitutively high sulfate concentration, it retains the ability to re-program its gene expression in response to reduced sulfate availability. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  3. Starvation-Survival in Haloarchaea.

    Science.gov (United States)

    Winters, Yaicha D; Lowenstein, Tim K; Timofeeff, Michael N

    2015-11-12

    Recent studies claiming to revive ancient microorganisms trapped in fluid inclusions in halite have warranted an investigation of long-term microbial persistence. While starvation-survival is widely reported for bacteria, it is less well known for halophilic archaea-microorganisms likely to be trapped in ancient salt crystals. To better understand microbial survival in fluid inclusions in ancient evaporites, laboratory experiments were designed to simulate growth of halophilic archaea under media-rich conditions, complete nutrient deprivation, and a controlled substrate condition (glycerol-rich) and record their responses. Haloarchaea used for this work included Hbt. salinarum and isolate DV582A-1 (genus Haloterrigena) sub-cultured from 34 kyear Death Valley salt. Hbt. salinarum and DV582A-1 reacted to nutrient limitation with morphological and population changes. Starved populations increased and most cells converted from rods to small cocci within 56 days of nutrient deprivation. The exact timing of starvation adaptations and the physical transformations differed between species, populations of the same species, and cells of the same population. This is the first study to report the timing of starvation strategies for Hbt. salinarum and DV582A-1. The morphological states in these experiments may allow differentiation between cells trapped with adequate nutrients (represented here by early stages in nutrient-rich media) from cells trapped without nutrients (represented here by experimental starvation) in ancient salt. The hypothesis that glycerol, leaked from Dunaliella, provides nutrients for the survival of haloarchaea trapped in fluid inclusions in ancient halite, is also tested. Hbt. salinarum and DV582A-1 were exposed to a mixture of lysed and intact Dunaliella for 56 days. The ability of these organisms to utilize glycerol from Dunaliella cells was assessed by documenting population growth, cell length, and cell morphology. Hbt. salinarum and DV582A-1

  4. Starvation-Survival in Haloarchaea

    Directory of Open Access Journals (Sweden)

    Yaicha D. Winters

    2015-11-01

    Full Text Available Recent studies claiming to revive ancient microorganisms trapped in fluid inclusions in halite have warranted an investigation of long-term microbial persistence. While starvation-survival is widely reported for bacteria, it is less well known for halophilic archaea—microorganisms likely to be trapped in ancient salt crystals. To better understand microbial survival in fluid inclusions in ancient evaporites, laboratory experiments were designed to simulate growth of halophilic archaea under media-rich conditions, complete nutrient deprivation, and a controlled substrate condition (glycerol-rich and record their responses. Haloarchaea used for this work included Hbt. salinarum and isolate DV582A-1 (genus Haloterrigena sub-cultured from 34 kyear Death Valley salt. Hbt. salinarum and DV582A-1 reacted to nutrient limitation with morphological and population changes. Starved populations increased and most cells converted from rods to small cocci within 56 days of nutrient deprivation. The exact timing of starvation adaptations and the physical transformations differed between species, populations of the same species, and cells of the same population. This is the first study to report the timing of starvation strategies for Hbt. salinarum and DV582A-1. The morphological states in these experiments may allow differentiation between cells trapped with adequate nutrients (represented here by early stages in nutrient-rich media from cells trapped without nutrients (represented here by experimental starvation in ancient salt. The hypothesis that glycerol, leaked from Dunaliella, provides nutrients for the survival of haloarchaea trapped in fluid inclusions in ancient halite, is also tested. Hbt. salinarum and DV582A-1 were exposed to a mixture of lysed and intact Dunaliella for 56 days. The ability of these organisms to utilize glycerol from Dunaliella cells was assessed by documenting population growth, cell length, and cell morphology. Hbt. salinarum

  5. A Conserved Two-Component Signal Transduction System Controls the Response to Phosphate Starvation in Bifidobacterium breve UCC2003.

    NARCIS (Netherlands)

    Alvarez-Martin, P.; Fernandez, M.; O'Connell-Motherway, M.; O'Connell, K.J.; Sauvageot, N.; Fitzgerald, G.F.; Macsharry, J.; Zomer, A.L.; Sinderen, D. van

    2012-01-01

    This work reports on the identification and molecular characterization of the two-component regulatory system (2CRS) PhoRP, which controls the response to inorganic phosphate (P(i)) starvation in Bifidobacterium breve UCC2003. The response regulator PhoP was shown to bind to the promoter region of

  6. Control of sulfate concentration by miR395-targeted APS genes in Arabidopsis thaliana

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    Qin Ai

    2016-04-01

    Full Text Available Sulfur nutrition is crucial for plant growth and development, as well as crop yield and quality. Inorganic sulfate in the soil is the major sulfur source for plants. After uptake, sulfate is activated by ATP sulfurylase, and then gets assimilated into sulfur-containing metabolites. However, the mechanism of regulation of sulfate levels by ATP sulfurylase is unclear. Here, we investigated the control of sulfate levels by miR395-mediated regulation of APS1/3/4. Sulfate was over-accumulated in the shoots of miR395 over-expression plants in which the expression of the APS1, APS3, and APS4 genes was suppressed. Accordingly, reduced expression of miR395 caused a decline of sulfate concentration. In agreement with these results, over-expression of the APS1, APS3, and APS4 genes led to the reduction of sulfate levels. Differential expression of these three APS genes in response to sulfate starvation implied that they have different functions. Further investigation revealed that the regulation of sulfate levels mediated by miR395 depends on the repression of its APS targets. Unlike the APS1, APS3, and APS4 genes, which encode plastid-localized ATP sulfurylases, the APS2 gene encodes a cytosolic version of ATP sulfurylase. Genetic analysis indicated that APS2 has no significant effect on sulfate levels. Our data suggest that miR395-targeted APS genes are key regulators of sulfate concentration in leaves.

  7. Starvation and recovery in the deep-sea methanotroph Methyloprofundus sedimenti.

    Science.gov (United States)

    Tavormina, Patricia L; Kellermann, Matthias Y; Antony, Chakkiath Paul; Tocheva, Elitza I; Dalleska, Nathan F; Jensen, Ashley J; Valentine, David L; Hinrichs, Kai-Uwe; Jensen, Grant J; Dubilier, Nicole; Orphan, Victoria J

    2017-01-01

    In the deep ocean, the conversion of methane into derived carbon and energy drives the establishment of diverse faunal communities. Yet specific biological mechanisms underlying the introduction of methane-derived carbon into the food web remain poorly described, due to a lack of cultured representative deep-sea methanotrophic prokaryotes. Here, the response of the deep-sea aerobic methanotroph Methyloprofundus sedimenti to methane starvation and recovery was characterized. By combining lipid analysis, RNA analysis, and electron cryotomography, it was shown that M. sedimenti undergoes discrete cellular shifts in response to methane starvation, including changes in headgroup-specific fatty acid saturation levels, and reductions in cytoplasmic storage granules. Methane starvation is associated with a significant increase in the abundance of gene transcripts pertinent to methane oxidation. Methane reintroduction to starved cells stimulates a rapid, transient extracellular accumulation of methanol, revealing a way in which methane-derived carbon may be routed to community members. This study provides new understanding of methanotrophic responses to methane starvation and recovery, and lays the initial groundwork to develop Methyloprofundus as a model chemosynthesizing bacterium from the deep sea. © 2016 John Wiley & Sons Ltd.

  8. Starvation, Together with the SOS Response, Mediates High Biofilm-Specific Tolerance to the Fluoroquinolone Ofloxacin

    Science.gov (United States)

    Bernier, Steve P.; Lebeaux, David; DeFrancesco, Alicia S.; Valomon, Amandine; Soubigou, Guillaume; Coppée, Jean-Yves; Ghigo, Jean-Marc; Beloin, Christophe

    2013-01-01

    High levels of antibiotic tolerance are a hallmark of bacterial biofilms. In contrast to well-characterized inherited antibiotic resistance, molecular mechanisms leading to reversible and transient antibiotic tolerance displayed by biofilm bacteria are still poorly understood. The physiological heterogeneity of biofilms influences the formation of transient specialized subpopulations that may be more tolerant to antibiotics. In this study, we used random transposon mutagenesis to identify biofilm-specific tolerant mutants normally exhibited by subpopulations located in specialized niches of heterogeneous biofilms. Using Escherichia coli as a model organism, we demonstrated, through identification of amino acid auxotroph mutants, that starved biofilms exhibited significantly greater tolerance towards fluoroquinolone ofloxacin than their planktonic counterparts. We demonstrated that the biofilm-associated tolerance to ofloxacin was fully dependent on a functional SOS response upon starvation to both amino acids and carbon source and partially dependent on the stringent response upon leucine starvation. However, the biofilm-specific ofloxacin increased tolerance did not involve any of the SOS-induced toxin–antitoxin systems previously associated with formation of highly tolerant persisters. We further demonstrated that ofloxacin tolerance was induced as a function of biofilm age, which was dependent on the SOS response. Our results therefore show that the SOS stress response induced in heterogeneous and nutrient-deprived biofilm microenvironments is a molecular mechanism leading to biofilm-specific high tolerance to the fluoroquinolone ofloxacin. PMID:23300476

  9. An optimal method of iron starvation of the obligate intracellular pathogen, Chlamydia trachomatis

    Directory of Open Access Journals (Sweden)

    Christopher C. Thompson

    2011-02-01

    Full Text Available Iron is an essential cofactor in a number of critical biochemical reactions, and as such, its acquisition, storage, and metabolism is highly regulated in most organisms. The obligate intracellular bacterium, Chlamydia trachomatis experiences a developmental arrest when iron within the host is depleted. The nature of the iron starvation response in Chlamydia is relatively uncharacterized because of the likely inefficient method of iron depletion, which currently relies on the compound deferoxamine mesylate (DFO. Inefficient induction of the iron starvation response precludes the identification of iron-regulated genes. This report evaluated DFO with another iron chelator, 2,2’-bipyridyl (Bpdl and presented a systematic comparison of the two across a range of criteria in a single-treatment time-of-infection regimen. We demonstrate that the membrane permeable Bpdl was superior to DFO in the inhibition of chlamydia development, the induction of aberrant morphology, and the induction of an iron starvation transcriptional response in both host and bacteria. Furthermore, iron starvation using Bpdl identified the periplasmic iron binding protein-encoding ytgA gene as iron- responsive. Overall, the data present a compelling argument for the use of Bpdl, rather than DFO, in future iron starvation studies of chlamydia and other intracellular bacteria.

  10. Starvation stress during larval development facilitates an adaptive response in adult worker honey bees (Apis mellifera L.).

    Science.gov (United States)

    Wang, Ying; Kaftanoglu, Osman; Brent, Colin S; Page, Robert E; Amdam, Gro V

    2016-04-01

    Most organisms are constantly faced with environmental changes and stressors. In diverse organisms, there is an anticipatory mechanism during development that can program adult phenotypes. The adult phenotype would be adapted to the predicted environment that occurred during organism maturation. However, whether this anticipatory mechanism is present in eusocial species is questionable because eusocial organisms are largely shielded from exogenous conditions by their stable nest environment. In this study, we tested whether food deprivation during development of the honey bee (Apis mellifera), a eusocial insect model, can shift adult phenotypes to better cope with nutritional stress. After subjecting fifth instar worker larvae to short-term starvation, we measured nutrition-related morphology, starvation resistance, physiology, endocrinology and behavior in the adults. We found that the larval starvation caused adult honey bees to become more resilient toward starvation. Moreover, the adult bees were characterized by reduced ovary size, elevated glycogen stores and juvenile hormone (JH) titers, and decreased sugar sensitivity. These changes, in general, can help adult insects survive and reproduce in food-poor environments. Overall, we found for the first time support for an anticipatory mechanism in a eusocial species, the honey bee. Our results suggest that this mechanism may play a role in honey bee queen-worker differentiation and worker division of labor, both of which are related to the responses to nutritional stress. © 2016. Published by The Company of Biologists Ltd.

  11. Ethylene signalling is involved in regulation of phosphate starvation-induced gene expression and production of acid phosphatases and anthocyanin in Arabidopsis

    KAUST Repository

    Lei, Mingguang

    2010-11-30

    With the exception of root hair development, the role of the phytohormone ethylene is not clear in other aspects of plant responses to inorganic phosphate (Pi) starvation. The induction of AtPT2 was used as a marker to find novel signalling components involved in plant responses to Pi starvation. Using genetic and chemical approaches, we examined the role of ethylene in the regulation of plant responses to Pi starvation. hps2, an Arabidopsis mutant with enhanced sensitivity to Pi starvation, was identified and found to be a new allele of CTR1 that is a key negative regulator of ethylene responses. 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, increases plant sensitivity to Pi starvation, whereas the ethylene perception inhibitor Ag+ suppresses this response. The Pi starvation-induced gene expression and acid phosphatase activity are also enhanced in the hps2 mutant, but suppressed in the ethylene-insensitive mutant ein2-5. By contrast, we found that ethylene signalling plays a negative role in Pi starvation-induced anthocyanin production. These findings extend the roles of ethylene in the regulation of plant responses to Pi starvation and will help us to gain a better understanding of the molecular mechanism underlying these responses. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust.

  12. Effects of starvation on the carbohydrate metabolism in Harmonia axyridis (Pallas

    Directory of Open Access Journals (Sweden)

    Zuo-Kun Shi

    2017-07-01

    Full Text Available Trehalose plays an important role in energy storage, metabolism, and protection from extreme environmental conditions in insects. Trehalose is the main blood sugar in insects, and it can be rapidly used as an energy source in times of need. To elucidate the mechanisms of the starvation response, we observed the effects of starvation on trehalose and glycogen, trehalase activity, and the relative gene expression of genes in the trehalose and glycogen metabolic pathways in the invasive beetle Harmonia axyridis. Our results show that trehalose levels and the activities of two types of trehalases decreased significantly in the first 8 h of starvation, while the relative expression of HaTreh1-1 increased. While trehalose remained nearly constant at a relatively high level from 8 to 24 h, glycogen levels decreased significantly from 8 h to 24 h of starvation. Likewise, glycogen phosphorylase (HaGP expression was significantly higher at 12 to 24 h starvation than the first 8 h, while the expression of glycogen synthase (HaGS was relatively stable. Furthermore, trehalose decreased significantly from 24 h starvation to 72 h starvation, while trehalase activities and the relative expression of some HaTreh genes generally increased toward the end of the starvation period. The expression of trehalose-6-phosphate synthase (HaTPS increased significantly, supporting the increase in trehalose synthesis. These results show that trehalose plays a key role in the energy provided during the starvation process through the molecular and biochemical regulation of trehalose and glycogen metabolism.

  13. An evolutionarily significant unicellular strategy in response to starvation stress in Dictyostelium social amoebae [v1; ref status: indexed, http://f1000r.es/3hg

    Directory of Open Access Journals (Sweden)

    Darja Dubravcic

    2014-06-01

    Full Text Available The social amoeba Dictyostelium discoideum is widely studied for its multicellular development program as a response to starvation and constitutes a model of choice in microbial cooperation studies. Aggregates of up to 106 cells form fruiting bodies containing two cell types: (i dormant spores (~80% that can persist for months in the absence of nutrients, and (ii dead stalk cells (~20% that promote the dispersion of the spores towards nutrient-rich areas. It is often overlooked that not all cells aggregate upon starvation. Using a new quantitative approach based on time-lapse fluorescence microscopy and a low ratio of reporting cells, we have quantified this fraction of non-aggregating cells. In realistic starvation conditions, up to 15% of cells do not aggregate, which makes this third cell fate a significant component of the population-level response of social amoebae to starvation. Non-aggregating cells have an advantage over cells in aggregates since they resume growth earlier upon arrival of new nutrients, but have a shorter lifespan under prolonged starvation. We find that phenotypic heterogeneities linked to cell nutritional state bias the representation of cells in the aggregating vs. non-aggregating fractions, and thus regulate population partitioning. Next, we report that the fraction of non-aggregating cells depends on genetic factors that regulate the timing of starvation, signal sensing efficiency and aggregation efficiency. In addition, interactions between clones in mixtures of non-isogenic cells affect the partitioning of each clone into both fractions. We further test the evolutionary significance of the non-aggregating cell fraction. The partitioning of cells into aggregating and non-aggregating fractions is optimal in fluctuating environments with an unpredictable duration of starvation periods. D. discoideum thus constitutes a model system lying at the intersection of microbial cooperation and bet hedging, defining a new

  14. A conserved two-component signal transduction system controls the response to phosphate starvation in Bifidobacterium breve UCC2003.

    Science.gov (United States)

    Alvarez-Martin, Pablo; Fernández, Matilde; O'Connell-Motherway, Mary; O'Connell, Kerry Joan; Sauvageot, Nicolas; Fitzgerald, Gerald F; MacSharry, John; Zomer, Aldert; van Sinderen, Douwe

    2012-08-01

    This work reports on the identification and molecular characterization of the two-component regulatory system (2CRS) PhoRP, which controls the response to inorganic phosphate (P(i)) starvation in Bifidobacterium breve UCC2003. The response regulator PhoP was shown to bind to the promoter region of pstSCAB, specifying a predicted P(i) transporter system, as well as that of phoU, which encodes a putative P(i)-responsive regulatory protein. This interaction is assumed to cause transcriptional modulation under conditions of P(i) limitation. Our data suggest that the phoRP genes are subject to positive autoregulation and, together with pstSCAB and presumably phoU, represent the complete regulon controlled by the phoRP-encoded 2CRS in B. breve UCC2003. Determination of the minimal PhoP binding region combined with bioinformatic analysis revealed the probable recognition sequence of PhoP, designated here as the PHO box, which together with phoRP is conserved among many high-GC-content Gram-positive bacteria. The importance of the phoRP 2CRS in the response of B. breve to P(i) starvation conditions was confirmed by analysis of a B. breve phoP insertion mutant which exhibited decreased growth under phosphate-limiting conditions compared to its parent strain UCC2003.

  15. Starvation increases insulin sensitivity and reduces juvenile hormone synthesis in mosquitoes.

    Directory of Open Access Journals (Sweden)

    Meritxell Perez-Hedo

    Full Text Available The interactions between the insulin signaling pathway (ISP and juvenile hormone (JH controlling reproductive trade-offs are well documented in insects. JH and insulin regulate reproductive output in mosquitoes; both hormones are involved in a complex regulatory network, in which they influence each other and in which the mosquito's nutritional status is a crucial determinant of the network's output. Previous studies reported that the insulin-TOR (target of rapamacyn signaling pathway is involved in the nutritional regulation of JH synthesis in female mosquitoes. The present studies further investigate the regulatory circuitry that controls both JH synthesis and reproductive output in response to nutrient availability.We used a combination of diet restriction, RNA interference (RNAi and insulin treatments to modify insulin signaling and study the cross-talk between insulin and JH in response to starvation. JH synthesis was analyzed using a newly developed assay utilizing fluorescent tags.Our results reveal that starvation decreased JH synthesis via a decrease in insulin signaling in the corpora allata (CA. Paradoxically, starvation-induced up regulation of insulin receptor transcripts and therefore "primed" the gland to respond rapidly to increases in insulin levels. During this response to starvation the synthetic potential of the CA remained unaffected, and the gland rapidly and efficiently responded to insulin stimulation by increasing JH synthesis to rates similar to those of CA from non-starved females.

  16. Characterization of the soybean GmALMT family genes and the function of GmALMT5 in response to phosphate starvation.

    Science.gov (United States)

    Peng, Wenting; Wu, Weiwei; Peng, Junchu; Li, Jiaojiao; Lin, Yan; Wang, Yanan; Tian, Jiang; Sun, Lili; Liang, Cuiyue; Liao, Hong

    2018-03-01

    A potential mechanism to enhance utilization of sparingly soluble forms of phosphorus (P) is the root secretion of malate, which is mainly mediated by the ALMT gene family in plants. In this study, a total of 34 GmALMT genes were identified in the soybean genome. Expression patterns diverged considerably among GmALMTs in response to phosphate (Pi) starvation in leaves, roots and flowers, with expression altered by P availability in 26 of the 34 GmALMTs. One root-specific GmALMT whose expression was significantly enhanced by Pi-starvation, GmALMT5, was studied in more detail to determine its possible role in soybean P nutrition. Analysis of GmALMT5 tissue expression patterns, subcellular localization, and malate exudation from transgenic soybean hairy roots overexpressing GmALMT5, demonstrated that GmALMT5 is a plasma membrane protein that mediates malate efflux from roots. Furthermore, both growth and P content of transgenic Arabidopsis overexpressing GmALMT5 were significantly increased when sparingly soluble Ca-P was used as the external P source. Taken together, these results indicate that members of the soybean GmALMT gene family exhibit diverse responses to Pi starvation. One member of this family, GmALMT5, might contribute to soybean P efficiency by enhancing utilization of sparingly soluble P sources under P limited conditions. © 2017 Institute of Botany, Chinese Academy of Sciences.

  17. Autophagy induction under carbon starvation conditions is negatively regulated by carbon catabolite repression.

    Science.gov (United States)

    Adachi, Atsuhiro; Koizumi, Michiko; Ohsumi, Yoshinori

    2017-12-01

    Autophagy is a conserved process in which cytoplasmic components are sequestered for degradation in the vacuole/lysosomes in eukaryotic cells. Autophagy is induced under a variety of starvation conditions, such as the depletion of nitrogen, carbon, phosphorus, zinc, and others. However, apart from nitrogen starvation, it remains unclear how these stimuli induce autophagy. In yeast, for example, it remains contentious whether autophagy is induced under carbon starvation conditions, with reports variously suggesting both induction and lack of induction upon depletion of carbon. We therefore undertook an analysis to account for these inconsistencies, concluding that autophagy is induced in response to abrupt carbon starvation when cells are grown with glycerol but not glucose as the carbon source. We found that autophagy under these conditions is mediated by nonselective degradation that is highly dependent on the autophagosome-associated scaffold proteins Atg11 and Atg17. We also found that the extent of carbon starvation-induced autophagy is positively correlated with cells' oxygen consumption rate, drawing a link between autophagy induction and respiratory metabolism. Further biochemical analyses indicated that maintenance of intracellular ATP levels is also required for carbon starvation-induced autophagy and that autophagy plays an important role in cell viability during prolonged carbon starvation. Our findings suggest that carbon starvation-induced autophagy is negatively regulated by carbon catabolite repression. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Evaluating death and activity decay of Anammox bacteria during anaerobic and aerobic starvation.

    Science.gov (United States)

    Wang, Qilin; Song, Kang; Hao, Xiaodi; Wei, Jing; Pijuan, Maite; van Loosdrecht, Mark C M; Zhao, Huijun

    2018-06-01

    The decreased activity (i.e. decay) of anaerobic ammonium oxidation (Anammox) bacteria during starvation can be attributed to death (i.e. decrease in the amount of viable bacteria) and activity decay (i.e. decrease in the specific activity of viable bacteria). Although they are crucial for the operation of the Anammox process, they have never been comprehensively investigated. This study for the first time experimentally assessed death and activity decay of the Anammox bacteria during 84 days' starvation stress based on ammonium removal rate, Live/Dead staining and fluorescence in-situ hybridization. The anaerobic and aerobic decay rates of Anammox bacteria were determined as 0.015 ± 0.001 d -1 and 0.028 ± 0.001 d -1 , respectively, indicating Anammox bacteria would lose their activity more quickly in the aerobic starvation than in the anaerobic starvation. The anaerobic and aerobic death rates of Anammox bacteria were measured at 0.011 ± 0.001 d -1 and 0.025 ± 0.001 d -1 , respectively, while their anaerobic and aerobic activity decay rates were determined at 0.004 ± 0.001 d -1 and 0.003 ± 0.001 d -1 , respectively. Further analysis revealed that death accounted for 73 ± 4% and 89 ± 5% of the decreased activity of Anammox bacteria during anaerobic and aerobic starvations, and activity decay was only responsible for 27 ± 4% and 11 ± 5% of the decreased Anammox activity, respectively, over the same starvation periods. These deeply shed light on the response of Anammox bacteria to the starvation stress, which would facilitate operation and optimization of the Anammox process. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. The effect of aerobic exercise and starvation on growth performance and postprandial metabolic response in juvenile southern catfish (Silurus meridionalis).

    Science.gov (United States)

    Li, Xiu-Ming; Liu, Li; Yuan, Jian-Ming; Xiao, Yuan-Yuan; Fu, Shi-Jian; Zhang, Yao-Guang

    2016-03-01

    To investigate the effects of aerobic exercise and starvation on growth performance, postprandial metabolic response and their interaction in a sedentary fish species, either satiation-fed or starved juvenile southern catfish (Silurus meridionalis) were exercised at 25 °C under three water velocities, i.e., nearly still water (control), 1 body length (bl) s(-1) and 2 bl s(-1), for eight weeks. Then, the feed intake (FI), food conversion efficiency (FCE), specific growth rate (SGR), morphological parameters, resting ṀO2 (ṀO2rest) and postprandial ṀO2 responses of the experimental fish were measured. Exercise at a low velocity (1 bl s(-1)) showed no effect on any growth performance parameter, whereas exercise at a high velocity (2 bl s(-1)) exhibited higher FI but similar SGR due to the extra energy expenditure from swimming and consequent decreased FCE. Starvation led to a significant body mass loss, whereas the effect intensified in both exercise groups. Exercise resulted in improved cardio-respiratory capacity, as indicated by increased gill and heart indexes, whereas it exhibited no effect on resting and postprandial metabolism in S. meridionalis. The starved fish displayed significantly larger heart, gill and digestive tract indexes compared with the feeding fish, suggesting selective maintenance of cardio-respiratory and digestive function in this fish species during starvation. However, starved fish still exhibited impaired digestive performance, as evidenced by the prolonged duration and low postprandial metabolic increase, and this effect was further exacerbated in both the 1 and 2 bl s(-1) exercise groups. These data suggest the following: (1) aerobic exercise produced no improvement in growth performance but may have led to the impairment of growth under insufficient food conditions; (2) the mass of different organs and tissues responded differently to aerobic exercise and starvation due to the different physiological roles they play; and (3

  20. Identification of Genes in Saccharomyces cerevisiae that Are Haploinsufficient for Overcoming Amino Acid Starvation

    Directory of Open Access Journals (Sweden)

    Nancy S. Bae

    2017-04-01

    Full Text Available The yeast Saccharomyces cerevisiae responds to amino acid deprivation by activating a pathway conserved in eukaryotes to overcome the starvation stress. We have screened the entire yeast heterozygous deletion collection to identify strains haploinsufficient for growth in the presence of sulfometuron methyl, which causes starvation for isoleucine and valine. We have discovered that cells devoid of MET15 are sensitive to sulfometuron methyl, and loss of heterozygosity at the MET15 locus can complicate screening the heterozygous deletion collection. We identified 138 cases of loss of heterozygosity in this screen. After eliminating the issues of the MET15 loss of heterozygosity, strains isolated from the collection were retested on sulfometuron methyl. To determine the general effect of the mutations for a starvation response, SMM-sensitive strains were tested for the ability to grow in the presence of canavanine, which induces arginine starvation, and strains that were MET15 were also tested for growth in the presence of ethionine, which causes methionine starvation. Many of the genes identified in our study were not previously identified as starvation-responsive genes, including a number of essential genes that are not easily screened in a systematic way. The genes identified span a broad range of biological functions, including many involved in some level of gene expression. Several unnamed proteins have also been identified, giving a clue as to possible functions of the encoded proteins.

  1. Previous Repeated Exposure to Food Limitation Enables Rats to Spare Lipid Stores during Prolonged Starvation.

    Science.gov (United States)

    McCue, Marshall D; Albach, Audrey; Salazar, Giovanni

    The risk of food limitation and, ultimately, starvation dates back to the dawn of heterotrophy in animals, yet starvation remains a major factor in the regulation of modern animal populations. Researchers studying starvation more than a century ago suggested that animals subjected to sublethal periods of food limitation are somehow more tolerant of subsequent starvation events. This possibility has received little attention over the past decades, yet it is highly relevant to modern science for two reasons. First, animals in natural populations are likely to be exposed to bouts of food limitation once or more before they face prolonged starvation, during which the risk of mortality becomes imminent. Second, our current approach to studying starvation physiology in the laboratory focuses on nourished animals with no previous exposure to nutritional stress. We examined the relationship between previous exposure to food limitation and potentially adaptive physiological responses to starvation in adult rats and found several significant differences. On two occasions, rats were fasted until they lost 20% of their body mass maintained lower body temperatures, and had presumably lower energy requirements when subjected to prolonged starvation than their naive cohort that never experienced food limitation. These rats that were trained in starvation also had lower plasma glucose set -points and reduced their reliance on endogenous lipid oxidation. These findings underscore (1) the need for biologists to revisit the classic hypothesis that animals can become habituated to starvation, using a modern set of research tools; and (2) the need to design controlled experiments of starvation physiology that more closely resemble the dynamic nature of food availability.

  2. Proteomic profiling of Mycobacterium tuberculosis identifies nutrient-starvation-responsive toxin-antitoxin systems

    DEFF Research Database (Denmark)

    Albrethsen, Jakob; Agner, Jeppe; Piersma, Sander R

    2013-01-01

    In order to successfully enter the latent stage, Mycobacterium tuberculosis must adapt to conditions such as nutrient limitation and hypoxia. In vitro models that mimic latent infection are valuable tools for describing the changes in metabolism that occur when the bacterium exists in a non......-growing form. We used two complementary proteomic approaches, label-free LC-MS/MS analysis and two-dimensional difference gel electrophoresis, to determine the proteome profile of extracellular proteins from M. tuberculosis cultured under nutrient starvation. Through the label-free LC-MS/MS analysis......, significant differences in the overall metabolism during nutrient starvation were detected. Notably, members of the toxin-antitoxin systems were present in larger quantities in nutrient-starved cultures, supporting a role for these global modules as M. tuberculosis switches its metabolism into dormancy...

  3. Carcass glycogen repletion on carbohydrate re-feeding after starvation.

    OpenAIRE

    Cox, D J; Palmer, T N

    1987-01-01

    In mice, the response of carcass glycogen to glucose re-feeding after starvation is biphasic. The initial repletive phase is followed by partial (greater than 50%) glycogen mobilization. This turnover of carcass glycogen in response to carbohydrate re-feeding may play an important role in the provision of C3 precursors for hepatic glycogen synthesis.

  4. OsWRKY74, a WRKY transcription factor, modulates tolerance to phosphate starvation in rice.

    Science.gov (United States)

    Dai, Xiaoyan; Wang, Yuanyuan; Zhang, Wen-Hao

    2016-02-01

    The WRKY transcription factor family has 109 members in the rice genome, and has been reported to be involved in the regulation of biotic and abiotic stress in plants. Here, we demonstrated that a rice OsWRKY74 belonging to group III of the WRKY transcription factor family was involved in tolerance to phosphate (Pi) starvation. OsWRKY74 was localized in the nucleus and mainly expressed in roots and leaves. Overexpression of OsWRKY74 significantly enhanced tolerance to Pi starvation, whereas transgenic lines with down-regulation of OsWRKY74 were sensitive to Pi starvation. Root and shoot biomass, and phosphorus (P) concentration in rice OsWRKY74-overexpressing plants were ~16% higher than those of wild-type (WT) plants in Pi-deficient hydroponic solution. In soil pot experiments, >24% increases in tiller number, grain weight and P concentration were observed in rice OsWRKY74-overexpressing plants compared to WT plants when grown in P-deficient medium. Furthermore, Pi starvation-induced changes in root system architecture were more profound in OsWRKY74-overexpressing plants than in WT plants. Expression patterns of a number of Pi-responsive genes were altered in the OsWRKY74-overexpressing and RNA interference lines. In addition, OsWRKY74 may also be involved in the response to deficiencies in iron (Fe) and nitrogen (N) as well as cold stress in rice. In Pi-deficient conditions, OsWRKY74-overexpressing plants exhibited greater accumulation of Fe and up-regulation of the cold-responsive genes than WT plants. These findings highlight the role of OsWRKY74 in modulation of Pi homeostasis and potential crosstalk between P starvation and Fe starvation, and cold stress in rice. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  5. Ionic and secretory response of pancreatic islet cells to minoxidil sulfate

    International Nuclear Information System (INIS)

    Antoine, M.H.; Hermann, M.; Herchuelz, A.; Lebrun, P.

    1991-01-01

    Minoxidil sulfate is an antihypertensive agent belonging to the new class of vasodilators, the K+ channel openers. The present study was undertaken to characterize the effects of minoxidil sulfate on ionic and secretory events in rat pancreatic islets. The drug unexpectedly provoked a concentration-dependent decrease in 86Rb outflow. This inhibitory effect was reduced in a concentration-dependent manner by glucose and tolbutamide. Minoxidil sulfate did not affect 45Ca outflow from islets perfused in the presence of extracellular Ca++ and absence or presence of glucose. However, in islets exposed to a medium deprived of extracellular Ca++, the drug provoked a rise in 45Ca outflow. Whether in the absence or presence of extracellular Ca++, minoxidil sulfate increased the cytosolic free Ca++ concentration of islet cells. Lastly, minoxidil sulfate increased the release of insulin from glucose-stimulated pancreatic islets. These results suggest that minoxidil sulfate reduces the activity of the ATP-sensitive K+ channels and promotes an intracellular translocation of Ca++. The latter change might account for the effect of the drug on the insulin-releasing process. However, the secretory response to minoxidil sulfate could also be mediated, at least in part, by a modest Ca++ entry

  6. The Role of Leptin in Maintaining Plasma Glucose During Starvation.

    Science.gov (United States)

    Perry, Rachel J; Shulman, Gerald I

    2018-03-01

    For 20 years it has been known that concentrations of leptin, a hormone produced by the white adipose tissue (WAT) largely in proportion to body fat, drops precipitously with starvation, particularly in lean humans and animals. The role of leptin to suppress the thyroid and reproductive axes during a prolonged fast has been well defined; however, the impact of leptin on metabolic regulation has been incompletely understood. However emerging evidence suggests that, in starvation, hypoleptinemia increases activity of the hypothalamic-pituitary-adrenal axis, promoting WAT lipolysis, increasing hepatic acetyl-CoA concentrations, and maintaining euglycemia. In addition, leptin may be largely responsible for mediating a shift from a reliance upon glucose metabolism (absorption and glycogenolysis) to fat metabolism (lipolysis increasing gluconeogenesis) which preserves substrates for the brain, heart, and other critical organs. In this way a leptin-mediated glucose-fatty acid cycle appears to maintain glycemia and permit survival in starvation.

  7. Starvation Based Differential Chemotherapy: A Novel Approach for Cancer Treatment

    Directory of Open Access Journals (Sweden)

    Sidra Naveed

    2014-11-01

    Full Text Available Cancer patients undergoing chemotherapy treatment are advised to increase food intake to overcome the therapy-induced side effects, and weight loss. Dietary restriction is known to slow down the aging process and hence reduce age-related diseases such as cancer. Fasting or short-term starvation is more effective than dietary restriction to prevent cancer growth since starved cells switch off signals for growth and reproduction and enter a protective mode, while cancer cells, being mutated, are not sensitized by any external growth signals and are not protected against any stress. This phenomenon is known as differential stress resistance (DSR. Nutrient signaling pathways involving growth hormone/insulin-like growth factor-1 axis and its downstream effectors, play a key role in DSR in response to starvation controlling the other cell maintenance systems, such as autophagy and apoptosis, that are related to the tumorigenesis. Yeast cells lacking these effectors are better protected against oxidative stress compared to normal cells. In the same way, starvation protects many cell lines and mice against high-dose chemotherapeutic drugs. According to a series of studies, fasting results in overall reduction in chemotherapy side effects in cancer patients. Data shows that starvation-dependent differential chemotherapy is safe, feasible and effective in cancer treatment, but the possible side effects of starvation limit its efficacy. However, further studies and clinical trials may result in its implementation in cancer treatment.

  8. Surviving starvation: essential role of the ghrelin-growth hormone axis.

    Science.gov (United States)

    Goldstein, J L; Zhao, T-j; Li, R L; Sherbet, D P; Liang, G; Brown, M S

    2011-01-01

    After brief starvation, vertebrates maintain blood glucose by releasing fatty acids from adipose tissue. The fatty acids provide energy for gluconeogenesis in liver and are taken up by muscle, sparing glucose. After prolonged starvation, fat stores are depleted, yet blood glucose can be maintained at levels sufficient to preserve life. Using a new mouse model, we demonstrate that survival after prolonged starvation requires ghrelin, an octanoylated peptide hormone that stimulates growth hormone (GH) secretion. We studied wild-type mice and mice lacking ghrelin as a result of knockout of GOAT, the enzyme that attaches octanoate to ghrelin. Mice were fed 40% of their normal intake for 7 d. Fat stores in both lines of mice became depleted after 4 d. On day 7, mice were fasted for 23 h. In wild-type mice, ghrelin and GH rose massively, and blood sugar was maintained at ~60 mg/dL. In Goat(-/-) mice, ghrelin was undetectable and GH failed to rise appropriately. Blood sugar declined to ~20 mg/dL, and the animals were moribund. Infusion of ghrelin or GH prevented hypoglycemia. Our results support the following sequence: (1) Starvation lowers blood glucose; (2) glucose-sensing neurons respond by activating sympathetic neurons; (3) norepinephrine, released in the stomach, stimulates ghrelin secretion; (4) ghrelin releases GH, which maintains blood glucose. Thus, ghrelin lies at the center of a hormonal response that permits mice to survive an acute fast superimposed on chronic starvation.

  9. Operation Starvation

    National Research Council Canada - National Science Library

    Mason, Gerald

    2002-01-01

    More than 1,250,000 tons of shipping was sunk or damaged in the last five months of World War II when Twenty-first Bomber Command executed an aerial mining campaign against Japan known as Operation STARVATION...

  10. Why does starvation make bones fat?

    Science.gov (United States)

    Devlin, Maureen J

    2011-01-01

    Body fat, or adipose tissue, is a crucial energetic buffer against starvation in humans and other mammals, and reserves of white adipose tissue (WAT) rise and fall in parallel with food intake. Much less is known about the function of bone marrow adipose tissue (BMAT), which are fat cells found in bone marrow. BMAT mass actually increases during starvation, even as other fat depots are being mobilized for energy. This review considers several possible reasons for this poorly understood phenomenon. Is BMAT a passive filler that occupies spaces left by dying bone cells, a pathological consequence of suppressed bone formation, or potentially an adaptation for surviving starvation? These possibilities are evaluated in terms of the effects of starvation on the body, particularly the skeleton, and the mechanisms involved in storing and metabolizing BMAT during negative energy balance. Copyright © 2011 Wiley-Liss, Inc.

  11. Eggs and hatchlings variations in desert locusts: phase related characteristics and starvation tolerance

    Directory of Open Access Journals (Sweden)

    Koutaro Ould Maeno

    2013-12-01

    Full Text Available Locusts are grasshopper species that express phase polyphenism: modifying their behavior, morphology, coloration, life history and physiology in response to crowding. Desert locusts, Schistocerca gregaria, epigenetically modify progeny quality and quantity in response to crowding. Gregarious (crowded females produce larger but fewer progeny than do solitarious (isolated ones. The variability of progeny quality within single egg pod and the reasons why gregarious progeny have a better survival than solitarious ones remains unclear. This study investigated 1 the effects of rearing density on the variation in egg size within single egg pods 2 the starvation tolerance of hatchlings from mothers with different phases and 3 the physiological differences in hatchling energy reserve. Isolated females produced smaller but more eggs than did crowded ones. The variation in egg size within egg pods was greater in the latter than in the former. A negative relationship between egg size and number of eggs per egg pod was observed for both groups. Under starvation conditions, gregarious hatchlings survived significantly longer than solitarious ones. Among the solitarious hatchlings, the survival time was longer as hatchling body size increased. However, small individuals survived as long as large ones among the gregarious hatchlings. The percentage of water content per fresh body weight was almost equal between the two phases, before and after starvation. In contrast, the percentage of lipid content per dry body weight was significantly higher in gregarious hatchlings than in solitarious ones before starvation, but became almost equal after starvation. These results demonstrated that female locusts not only trade-off to modify their progeny size and number, but also vary progenies’ energy reserves. We hypothesized that gregarious females enhance their fitness by producing progeny differently adapted to high environmental variability and particularly to

  12. Sex-specific starvation tolerance of copepods with different foraging strategies

    DEFF Research Database (Denmark)

    Holm, Mark Wejlemann; Torres, Rocio Rodriguez; van Someren Gréve, Hans

    2018-01-01

    in starvation tolerance are not due to dissimilarities in lipid reserves. Gender differences in starvation tolerance can be partially explained by body size differences between sexes. This indicates a minor influence of mate-seeking behaviour on male starvation tolerance, likely due to reduced mate......Planktonic copepods have sexual dimorphism that can lead to differences in starvation tolerance between genders. Additionally, mating may be energetically costly and thus reduce starvation tolerance. We investigated the influence of sexual dimorphism and mating on starvation tolerance of copepods...... with different feeding behaviours: Oithona nana (ambusher), Temora longicornis (feeding-current feeder) and Centropages typicus (cruiser). Males of C. typicus and O. nana had a starvation tolerance lower than females, whereas T. longicornis had a similar starvation tolerance between genders. Only O. nana males...

  13. Effects of repeated cycles of starvation and refeeding on lungs of growing rats.

    Science.gov (United States)

    Sahebjami, H; Domino, M

    1992-12-01

    Adult male rats were subjected to four cycles of mild starvation (2 wk) and refeeding (1 wk) and were compared with a fed group. Starvation was induced by giving rats one-third of their measured daily food consumption. During each starvation cycle, rats lost approximately 20% of their body weight. Despite catch-up growth and overall weight gain, starved rats had lower final body weight than fed rats. Lung dry weight and lung volumes were also reduced in the starved group. The mechanical properties of air- and saline-filled lungs did not change significantly with repeated cycles of starvation. Mean linear intercept was similar in the two groups, but alveolar surface area was reduced in the starved rats. Total content of crude connective tissue and concentration per lung dry weight of hydroxyproline and crude connective tissue were reduced in starved rats. We conclude that lung growth is retarded in growing rats subjected to repeated cycles of mild starvation and refeeding, as manifested by smaller lung volume and reduced alveolar surface area. Because alveolar size is unchanged, a reduced number of alveoli is most likely responsible for decreased lung volumes.

  14. Starvation-free mutual exclusion with semaphores

    NARCIS (Netherlands)

    Hesselink, Wim H.; IJbema, Mark

    The standard implementation of mutual exclusion by means of a semaphore allows starvation of processes. Between 1979 and 1986, three algorithms were proposed that preclude starvation. These algorithms use a special kind of semaphore. We model this so-called buffered semaphore rigorously and provide

  15. Arabidopsis roots and shoots show distinct temporal adaptation patterns toward nitrogen starvation.

    Science.gov (United States)

    Krapp, Anne; Berthomé, Richard; Orsel, Mathilde; Mercey-Boutet, Stéphanie; Yu, Agnes; Castaings, Loren; Elftieh, Samira; Major, Hilary; Renou, Jean-Pierre; Daniel-Vedele, Françoise

    2011-11-01

    Nitrogen (N) is an essential macronutrient for plants. N levels in soil vary widely, and plants have developed strategies to cope with N deficiency. However, the regulation of these adaptive responses and the coordinating signals that underlie them are still poorly understood. The aim of this study was to characterize N starvation in adult Arabidopsis (Arabidopsis thaliana) plants in a spatiotemporal manner by an integrative, multilevel global approach analyzing growth, metabolites, enzyme activities, and transcript levels. We determined that the remobilization of N and carbon compounds to the growing roots occurred long before the internal N stores became depleted. A global metabolite analysis by gas chromatography-mass spectrometry revealed organ-specific differences in the metabolic adaptation to complete N starvation, for example, for several tricarboxylic acid cycle intermediates, but also for carbohydrates, secondary products, and phosphate. The activities of central N metabolism enzymes and the capacity for nitrate uptake adapted to N starvation by favoring N remobilization and by increasing the high-affinity nitrate uptake capacity after long-term starvation. Changes in the transcriptome confirmed earlier studies and added a new dimension by revealing specific spatiotemporal patterns and several unknown N starvation-regulated genes, including new predicted small RNA genes. No global correlation between metabolites, enzyme activities, and transcripts was evident. However, this multilevel spatiotemporal global study revealed numerous new patterns of adaptation mechanisms to N starvation. In the context of a sustainable agriculture, this work will give new insight for the production of crops with increased N use efficiency.

  16. Management of starvation in a Role 1 setting.

    Science.gov (United States)

    Jeffery, S M T; Freshwater, D A

    2012-01-01

    Historical reports from war and natural disasters first identified the dangers of reintroducing food after a period of starvation or malnutrition. The development of advanced nutritional support for hospitalised patients gave rise to the concept of refeeding syndrome, further highlighting the problems and leading to the development of guidelines and protocols for managing malnutrition. In this paper we present a case of starvation in the maritime setting and review the pathophysiology of starvation and refeeding. We discuss the problems associated with managing acute starvation in a Role 1 setting without access to higher medical care, and present guidance for its management.

  17. Transaldolase inhibition impairs mitochondrial respiration and induces a starvation-like longevity response in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Christopher F Bennett

    2017-03-01

    Full Text Available Mitochondrial dysfunction can increase oxidative stress and extend lifespan in Caenorhabditis elegans. Homeostatic mechanisms exist to cope with disruptions to mitochondrial function that promote cellular health and organismal longevity. Previously, we determined that decreased expression of the cytosolic pentose phosphate pathway (PPP enzyme transaldolase activates the mitochondrial unfolded protein response (UPRmt and extends lifespan. Here we report that transaldolase (tald-1 deficiency impairs mitochondrial function in vivo, as evidenced by altered mitochondrial morphology, decreased respiration, and increased cellular H2O2 levels. Lifespan extension from knockdown of tald-1 is associated with an oxidative stress response involving p38 and c-Jun N-terminal kinase (JNK MAPKs and a starvation-like response regulated by the transcription factor EB (TFEB homolog HLH-30. The latter response promotes autophagy and increases expression of the flavin-containing monooxygenase 2 (fmo-2. We conclude that cytosolic redox established through the PPP is a key regulator of mitochondrial function and defines a new mechanism for mitochondrial regulation of longevity.

  18. PfeIK1, a eukaryotic initiation factor 2α kinase of the human malaria parasite Plasmodium falciparum, regulates stress-response to amino-acid starvation

    Directory of Open Access Journals (Sweden)

    Ranford-Cartwright Lisa

    2009-05-01

    Full Text Available Abstract Background Post-transcriptional control of gene expression is suspected to play an important role in malaria parasites. In yeast and metazoans, part of the stress response is mediated through phosphorylation of eukaryotic translation initiation factor 2α (eIF2α, which results in the selective translation of mRNAs encoding stress-response proteins. Methods The impact of starvation on the phosphorylation state of PfeIF2α was examined. Bioinformatic methods were used to identify plasmodial eIF2α kinases. The activity of one of these, PfeIK1, was investigated using recombinant protein with non-physiological substrates and recombinant PfeIF2α. Reverse genetic techniques were used to disrupt the pfeik1 gene. Results The data demonstrate that the Plasmodium falciparum eIF2α orthologue is phosphorylated in response to starvation, and provide bioinformatic evidence for the presence of three eIF2α kinases in P. falciparum, only one of which (PfPK4 had been described previously. Evidence is provided that one of the novel eIF2α kinases, PfeIK1, is able to phosphorylate the P. falciparum eIF2α orthologue in vitro. PfeIK1 is not required for asexual or sexual development of the parasite, as shown by the ability of pfeik1- parasites to develop into sporozoites. However, eIF2α phosphorylation in response to starvation is abolished in pfeik1- asexual parasites Conclusion This study strongly suggests that a mechanism for versatile regulation of translation by several kinases with a similar catalytic domain but distinct regulatory domains, is conserved in P. falciparum.

  19. Starvation-induced activation of ATM/Chk2/p53 signaling sensitizes cancer cells to cisplatin

    Directory of Open Access Journals (Sweden)

    Shi Yandong

    2012-12-01

    Full Text Available Abstract Background Optimizing the safety and efficacy of standard chemotherapeutic agents such as cisplatin (CDDP is of clinical relevance. Serum starvation in vitro and short-term food starvation in vivo both stress cells by the sudden depletion of paracrine growth stimulation. Methods The effects of serum starvation on CDDP toxicity were investigated in normal and cancer cells by assessing proliferation, cell cycle distribution and activation of DNA-damage response and of AMPK, and were compared to effects observed in cells grown in serum-containing medium. The effects of short-term food starvation on CDDP chemotherapy were assessed in xenografts-bearing mice and were compared to effects on tumor growth and/or regression determined in mice with no diet alteration. Results We observed that serum starvation in vitro sensitizes cancer cells to CDDP while protecting normal cells. In detail, in normal cells, serum starvation resulted in a complete arrest of cellular proliferation, i.e. depletion of BrdU-incorporation during S-phase and accumulation of the cells in the G0/G1-phase of the cell cycle. Further analysis revealed that proliferation arrest in normal cells is due to p53/p21 activation, which is AMPK-dependent and ATM-independent. In cancer cells, serum starvation also decreased the fraction of S-phase cells but to a minor extent. In contrast to normal cells, serum starvation-induced p53 activation in cancer cells is both AMPK- and ATM-dependent. Combination of CDDP with serum starvation in vitro increased the activation of ATM/Chk2/p53 signaling pathway compared to either treatment alone resulting in an enhanced sensitization of cancer cells to CDDP. Finally, short-term food starvation dramatically increased the sensitivity of human tumor xenografts to cisplatin as indicated not only by a significant growth delay, but also by the induction of complete remission in 60% of the animals bearing mesothelioma xenografts, and in 40% of the

  20. Adaptive response to starvation in the fish pathogen Flavobacterium columnare: cell viability and ultrastructural changes

    Directory of Open Access Journals (Sweden)

    Arias Covadonga R

    2012-11-01

    Full Text Available Abstract Background The ecology of columnaris disease, caused by Flavobacterium columnare, is poorly understood despite the economic losses that this disease inflicts on aquaculture farms worldwide. Currently, the natural reservoir for this pathogen is unknown but limited data have shown its ability to survive in water for extended periods of time. The objective of this study was to describe the ultrastructural changes that F. columnare cells undergo under starvation conditions. Four genetically distinct strains of this pathogen were monitored for 14 days in media without nutrients. Culturability and cell viability was assessed throughout the study. In addition, cell morphology and ultrastructure was analyzed using light microscopy, scanning electron microscopy, and transmission electron microscopy. Revival of starved cells under different nutrient conditions and the virulence potential of the starved cells were also investigated. Results Starvation induced unique and consistent morphological changes in all strains studied. Cells maintained their length and did not transition into a shortened, coccus shape as observed in many other Gram negative bacteria. Flavobacterium columnare cells modified their shape by morphing into coiled forms that comprised more than 80% of all the cells after 2 weeks of starvation. Coiled cells remained culturable as determined by using a dilution to extinction strategy. Statistically significant differences in cell viability were found between strains although all were able to survive in absence of nutrients for at least 14 days. In later stages of starvation, an extracellular matrix was observed covering the coiled cells. A difference in growth curves between fresh and starved cultures was evident when cultures were 3-months old but not when cultures were starved for only 1 month. Revival of starved cultures under different nutrients revealed that cells return back to their original elongated rod shape upon

  1. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Science.gov (United States)

    Pittman, Joseph R.; Kline, La’Kesha C.; Kenyon, William J.

    2015-01-01

    The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation) is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance). To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C), low pH (pH 2.8), and oxidative stress (15 mM H2O2). In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth. PMID:27682115

  2. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Directory of Open Access Journals (Sweden)

    Joseph R. Pittman

    2015-10-01

    Full Text Available The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance. To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C, low pH (pH 2.8, and oxidative stress (15 mM H2O2. In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth.

  3. Evidence for the adverse effect of starvation on bone quality: a review of the literature.

    Science.gov (United States)

    Kueper, Janina; Beyth, Shaul; Liebergall, Meir; Kaplan, Leon; Schroeder, Josh E

    2015-01-01

    Malnutrition and starvation's possible adverse impacts on bone health and bone quality first came into the spotlight after the horrors of the Holocaust and the ghettos of World War II. Famine and food restrictions led to a mean caloric intake of 200-800 calories a day in the ghettos and concentration camps, resulting in catabolysis and starvation of the inhabitants and prisoners. Severely increased risks of fracture, poor bone mineral density, and decreased cortical strength were noted in several case series and descriptive reports addressing the medical issues of these individuals. A severe effect of severely diminished food intake and frequently concomitant calcium- and Vitamin D deficiencies was subsequently proven in both animal models and the most common cause of starvation in developed countries is anorexia nervosa. This review attempts to summarize the literature available on the impact of the metabolic response to Starvation on overall bone health and bone quality.

  4. Starvation stress affects the interplay among shrimp gut microbiota, digestion and immune activities.

    Science.gov (United States)

    Dai, Wen-Fang; Zhang, Jin-Jie; Qiu, Qiong-Fen; Chen, Jiong; Yang, Wen; Ni, Sui; Xiong, Jin-Bo

    2018-05-24

    Aquatic animals are frequently suffered from starvation due to restricted food availability or deprivation. It is currently known that gut microbiota assists host in nutrient acquisition. Thus, exploring the gut microbiota responses would improve our understanding on physiological adaptation to starvation. To achieve this, we investigated how the gut microbiota and shrimp digestion and immune activities were affected under starvation stress. The results showed that the measured digestion activities in starved shrimp were significantly lower than in normal cohorts; while the measured immune activities exhibited an opposite trend. A structural equation modeling (SEM) revealed that changes in the gut bacterial community were directly related to digestive and immune enzyme activities, which in turn markedly affected shrimp growth traits. Notably, several gut bacterial indicators that characterized the shrimp nutrient status were identified, with more abundant opportunistic pathogens in starved shrimp, although there were no statistical differences in the overall diversity and the structures of gut bacterial communities between starved and normal shrimp. Starved shrimp exhibited less connected and cooperative interspecies interaction as compared with normal cohorts. Additionally, the functional pathways involved in carbohydrate and protein digestion, glycan biosynthesis, lipid and enzyme metabolism remarkably decreased in starved shrimp. These attenuations could increase the susceptibility of starved shrimp to pathogens infection. In summary, this study provides novel insights into the interplay among shrimp digestion, immune activities and gut microbiota in response to starvation stress. Copyright © 2018. Published by Elsevier Ltd.

  5. Relative Importance of Sex, Pre-Starvation Body Mass and Structural Body Size in the Determination of Exceptional Starvation Resistance of Anchomenus dorsalis (Coleoptera: Carabidae.

    Directory of Open Access Journals (Sweden)

    Michal Knapp

    Full Text Available In nature, almost all animals have to cope with periods of food shortage during their lifetimes. Starvation risks are especially high for carnivorous predatory species, which often experience long intervals between stochastic prey capturing events. A laboratory experiment using the common predatory carabid beetle Anchomenus dorsalis revealed an exceptional level of starvation resistance in this species: males survived up to 137 days and females up to 218 days without food at 20°C. Individual starvation resistance was strongly positively affected by pre-starvation body mass but only slightly by beetle structural body size per se. Females outperformed males even when the effect of gender was corrected for the effects of structural body size and pre-starvation body mass. The better performance of females compared to males and of beetles with higher relative pre-starvation body mass could be linked to higher fat content and lean dry mass before starvation, followed by a greater decrease in both during starvation. There was also a difference between the sexes in the extent of body mass changes both during ad libitum feeding and following starvation; the body masses of females fluctuated more compared to males. This study stresses the need to distinguish between body mass and structural body size when investigating the ecological and evolutionary consequences of body size. Investigation of the net effects of body size and sex is necessary to disentangle the causes of differences in individual performances in studies of species with significant sexual size dimorphism.

  6. Characterization of starvation-induced dispersion in Pseudomonas putida biofilms

    DEFF Research Database (Denmark)

    Gjermansen, Morten; Ragas, Paula Cornelia; Sternberg, Claus

    2005-01-01

    The biofilm lifestyle, where microbial cells are aggregated because of expression of cell-to-cell interconnecting compounds, is believed to be of paramount importance to microbes in the environment. Because microbes must be able to alternate between sessile and planktonic states, it is anticipated...... that they must be able to regulate their ability to form biofilm and to dissolve biofilm. We present an investigation of a biofilm dissolution process occurring in flow-chamber-grown Pseudomonas putida biofilms. Local starvation-induced biofilm dissolution appears to be an integrated part of P. putida biofilm...... development that causes characteristic structural rearrangements. Rapid global dissolution of entire P. putida biofilms was shown to occur in response to carbon starvation. Genetic analysis suggested that the adjacent P. putida genes PP0164 and PP0165 play a role in P. putida biofilm formation and dissolution...

  7. Sulfate transporters in the plant’s response to drought and salinity: regulation and possible functions

    Directory of Open Access Journals (Sweden)

    Karine eGallardo

    2014-10-01

    Full Text Available Drought and salinity are two frequently combined abiotic stresses that affect plant growth, development, and crop productivity. Sulfate, and molecules derived from this anion such as glutathione, play important roles in the intrinsic responses of plants to such abiotic stresses. Therefore, understanding how plants facing environmental constraints re-equilibrate the flux of sulfate between and within different tissues might uncover perspectives for improving tolerance against abiotic stresses. In this review, we took advantage of genomics and post-genomics resources available in Arabidopsis thaliana and in the model legume species Medicago truncatula to highlight and compare the regulation of sulfate transporter genes under drought and salt stress. We also discuss their possible function in the plant’s response and adaptation to abiotic stresses and present prospects about the potential benefits of mycorrhizal associations, which by facilitating sulfate uptake may assist plants to cope with abiotic stresses. Several transporters are highlighted in this review that appear promising targets for improving sulfate transport capacities of crops under fluctuating environmental conditions.

  8. Nitrogen Starvation Acclimation in Synechococcus elongatus: Redox-Control and the Role of Nitrate Reduction as an Electron Sink

    Directory of Open Access Journals (Sweden)

    Alexander Klotz

    2015-03-01

    Full Text Available Nitrogen starvation acclimation in non-diazotrophic cyanobacteria is characterized by a process termed chlorosis, where the light harvesting pigments are degraded and the cells gradually tune down photosynthetic and metabolic activities. The chlorosis response is governed by a complex and poorly understood regulatory network, which converges at the expression of the nblA gene, the triggering factor for phycobiliprotein degradation. This study established a method that allows uncoupling metabolic and redox-signals involved in nitrogen-starvation acclimation. Inhibition of glutamine synthetase (GS by a precise dosage of l-methionine-sulfoximine (MSX mimics the metabolic situation of nitrogen starvation. Addition of nitrate to such MSX-inhibited cells eliminates the associated redox-stress by enabling electron flow towards nitrate/nitrite reduction and thereby, prevents the induction of nblA expression and the associated chlorosis response. This study demonstrates that nitrogen starvation is perceived not only through metabolic signals, but requires a redox signal indicating over-reduction of PSI-reduced electron acceptors. It further establishes a cryptic role of nitrate/nitrite reductases as electron sinks to balance conditions of over-reduction.

  9. Nitrogen Starvation Acclimation in Synechococcus elongatus: Redox-Control and the Role of Nitrate Reduction as an Electron Sink

    Science.gov (United States)

    Klotz, Alexander; Reinhold, Edgar; Doello, Sofía; Forchhammer, Karl

    2015-01-01

    Nitrogen starvation acclimation in non-diazotrophic cyanobacteria is characterized by a process termed chlorosis, where the light harvesting pigments are degraded and the cells gradually tune down photosynthetic and metabolic activities. The chlorosis response is governed by a complex and poorly understood regulatory network, which converges at the expression of the nblA gene, the triggering factor for phycobiliprotein degradation. This study established a method that allows uncoupling metabolic and redox-signals involved in nitrogen-starvation acclimation. Inhibition of glutamine synthetase (GS) by a precise dosage of l-methionine-sulfoximine (MSX) mimics the metabolic situation of nitrogen starvation. Addition of nitrate to such MSX-inhibited cells eliminates the associated redox-stress by enabling electron flow towards nitrate/nitrite reduction and thereby, prevents the induction of nblA expression and the associated chlorosis response. This study demonstrates that nitrogen starvation is perceived not only through metabolic signals, but requires a redox signal indicating over-reduction of PSI-reduced electron acceptors. It further establishes a cryptic role of nitrate/nitrite reductases as electron sinks to balance conditions of over-reduction. PMID:25780959

  10. Transcriptome profiling of sulfate deprivation responses in two agarophytes Gracilaria changii and Gracilaria salicornia (Rhodophyta).

    Science.gov (United States)

    Lee, Wei-Kang; Namasivayam, Parameswari; Ong Abdullah, Janna; Ho, Chai-Ling

    2017-04-24

    Seaweeds survive in marine waters with high sulfate concentration compared to those living at freshwater habitats. The cell wall polymer of Gracilaria spp. which supplies more than 50% of the world agar is heavily sulfated. Since sulfation reduces the agar quality, it is interesting to investigate the effects of sulfate deprivation on the sulfate contents of seaweed and agar, as well as the metabolic pathways of these seaweeds. In this study, two agarophytes G. changii and G. salicornia were treated under sulfate deprivation for 5 days. The sulfate contents in the seaweed/agar were generally lower in sulfate-deprivated samples compared to those in the controls, but the differences were only statistically significant for seaweed sample of G. changii and agar sample of G. salicornia. RNA sequencing (RNA-Seq) of sulfate-deprivated and untreated seaweed samples revealed 1,292 and 3,439 differentially expressed genes (DEGs; ≥1.5-fold) in sulfate-deprivated G. changii and G. salicornia, respectively, compared to their respective controls. Among the annotated DEGs were genes involved in putative agar biosynthesis, sulfur metabolism, metabolism of sulfur-containing amino acids, carbon metabolism and oxidative stress. These findings shed light on the sulfate deprivation responses in agarophytes and help to identify candidate genes involved in agar biosynthesis.

  11. Plasmodium falciparum responds to amino acid starvation by entering into a hibernatory state.

    Science.gov (United States)

    Babbitt, Shalon E; Altenhofen, Lindsey; Cobbold, Simon A; Istvan, Eva S; Fennell, Clare; Doerig, Christian; Llinás, Manuel; Goldberg, Daniel E

    2012-11-20

    The human malaria parasite Plasmodium falciparum is auxotrophic for most amino acids. Its amino acid needs are met largely through the degradation of host erythrocyte hemoglobin; however the parasite must acquire isoleucine exogenously, because this amino acid is not present in adult human hemoglobin. We report that when isoleucine is withdrawn from the culture medium of intraerythrocytic P. falciparum, the parasite slows its metabolism and progresses through its developmental cycle at a reduced rate. Isoleucine-starved parasites remain viable for 72 h and resume rapid growth upon resupplementation. Protein degradation during starvation is important for maintenance of this hibernatory state. Microarray analysis of starved parasites revealed a 60% decrease in the rate of progression through the normal transcriptional program but no other apparent stress response. Plasmodium parasites do not possess a TOR nutrient-sensing pathway and have only a rudimentary amino acid starvation-sensing eukaryotic initiation factor 2α (eIF2α) stress response. Isoleucine deprivation results in GCN2-mediated phosphorylation of eIF2α, but kinase-knockout clones still are able to hibernate and recover, indicating that this pathway does not directly promote survival during isoleucine starvation. We conclude that P. falciparum, in the absence of canonical eukaryotic nutrient stress-response pathways, can cope with an inconsistent bloodstream amino acid supply by hibernating and waiting for more nutrient to be provided.

  12. Global mapping of protein phosphorylation events identifies novel signalling hubs mediating fatty acid starvation responses in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Pultz, Dennis; Bennetzen, Martin; Rødkær, Steven Vestergaard

    2011-01-01

    Dietary restriction (DR) extends the life span of multiple species, ranging from single-celled organisms like yeast to mammals. This increase in longevity by dietary restriction is coupled to profound beneficial effects on age-related pathology. Despite the number of studies on DR...... and the physiological changes DR induces, only little is known about the genetics and signalling networks, which regulate the DR response. We have recently shown that inhibition of fatty acid synthesis in Saccharomyces cerevisiae induces autophagy mediated by TORC1 signalling and affects life span. In the present study...... in a temporal manner in response to inhibition of fatty acid synthesis by cerulenin. By in silico analysis of these phosphorylation events, we have identified the major downstream regulated processes and signalling networks mediating the cellular response to fatty acid starvation. The analysis further...

  13. Why does starvation make bones fat?

    OpenAIRE

    Devlin, Maureen J.

    2011-01-01

    Body fat, or adipose tissue, is a crucial energetic buffer against starvation in humans and other mammals, and reserves of white adipose tissue (WAT) rise and fall in parallel with food intake. Much less is known about the function of bone marrow adipose tissue (BMAT), which are fat cells found in bone marrow. BMAT mass actually increases during starvation, even as other fat depots are being mobilized for energy. Here I review the possible reasons for this poorly understood phenomenon. Is BMA...

  14. Starvation-survival of subsurface bacteria

    International Nuclear Information System (INIS)

    Magill, N.G.

    1988-01-01

    The ability of four subsurface isolates to survive starvation was examined and the results were compared to survival curves obtained for Escherichia coli B and Serratia marcescens. To examine the starvation-survival phenomenon further, several experimental parameters including nutritional history, initial cell density, growth phase, temperature of growth and starvation, and aeration. Nutritional history, initial cell density, and growth phases of the cells had some effect on the ability of these bacteria to survive whereas temperature and limited aeration had no effect under the conditions tested. No conditions were found where E. coli B or Serratia marcescens died rapidly or where less than 10% of the original cell number of viable cells remained. Because the apparent survival of these bacteria may be due to cryptic growth, cross-feeding experiments with 14 C-labeled cells and unlabeled cells were carried out with E. coli B and Pseudomonas Lula V. Leaked extracellular 14 C-compounds were not used for growth or maintenance energy, and were not taken up by either bacterium. Cryptic growth did not occur; the cells were truly starving under the experimental conditions used

  15. Facilitated recruitment of Pdc2p, a yeast transcriptional activator, in response to thiamin starvation.

    Science.gov (United States)

    Nosaka, Kazuto; Esaki, Hiroyoshi; Onozuka, Mari; Konno, Hiroyuki; Hattori, Yasunao; Akaji, Kenichi

    2012-05-01

    In Saccharomyces cerevisiae, genes involved in thiamin pyrophosphate (TPP) synthesis (THI genes) and the pyruvate decarboxylase structural gene PDC5 are transcriptionally induced in response to thiamin starvation. Three positive regulatory factors (Thi2p, Thi3p, and Pdc2p) are involved in the expression of THI genes, whereas only Pdc2p is required for the expression of PDC5. Thi2p and Pdc2p serve as transcriptional activators and each factor can interact with Thi3p. The target consensus DNA sequence of Thi2p has been deduced. When TPP is not bound to Thi3p, the interactions between the regulatory factors are increased and THI gene expression is upregulated. In this study, we demonstrated that Pdc2p interacts with the upstream region of THI genes and PDC5. The association of Pdc2p or Thi2p with THI gene promoters was enhanced by thiamin starvation, suggesting that Pdc2p and Thi2p assist each other in their recruitment to the THI promoters via interaction with Thi3p. It is highly likely that, under thiamin-deprived conditions, a ternary Thi2p/Thi3p/Pdc2p complex is formed and transactivates THI genes in yeast cells. On the other hand, the association of Pdc2p with PDC5 was unaffected by thiamin. We also identified a DNA element in the upstream region of PDC5, which can bind to Pdc2p and is required for the expression of PDC5. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  16. Cloud albedo changes in response to anthropogenic sulfate and non-sulfate aerosol forcings in CMIP5 models

    Directory of Open Access Journals (Sweden)

    L. Frey

    2017-07-01

    Full Text Available The effects of different aerosol types on cloud albedo are analysed using the linear relation between total albedo and cloud fraction found on a monthly mean scale in regions of subtropical marine stratocumulus clouds and the influence of simulated aerosol variations on this relation. Model experiments from the Coupled Model Intercomparison Project phase 5 (CMIP5 are used to separately study the responses to increases in sulfate, non-sulfate and all anthropogenic aerosols. A cloud brightening on the month-to-month scale due to variability in the background aerosol is found to dominate even in the cases where anthropogenic aerosols are added. The aerosol composition is of importance for this cloud brightening, that is thereby region dependent. There is indication that absorbing aerosols to some extent counteract the cloud brightening but scene darkening with increasing aerosol burden is generally not supported, even in regions where absorbing aerosols dominate. Month-to-month cloud albedo variability also confirms the importance of liquid water content for cloud albedo. Regional, monthly mean cloud albedo is found to increase with the addition of anthropogenic aerosols and more so with sulfate than non-sulfate. Changes in cloud albedo between experiments are related to changes in cloud water content as well as droplet size distribution changes, so that models with large increases in liquid water path and/or cloud droplet number show large cloud albedo increases with increasing aerosol. However, no clear relation between model sensitivities to aerosol variations on the month-to-month scale and changes in cloud albedo due to changed aerosol burden is found.

  17. Pioneer round of translation occurs during serum starvation

    International Nuclear Information System (INIS)

    Oh, Nara; Kim, Kyoung Mi; Cho, Hana; Choe, Junho; Kim, Yoon Ki

    2007-01-01

    The pioneer round of translation plays a role in translation initiation of newly spliced and exon junction complex (EJC)-bound mRNAs. Nuclear cap-binding protein complex CBP80/20 binds to those mRNAs at the 5'-end, recruiting translation initiation complex. As a consequence of the pioneer round of translation, the bound EJCs are dissociated from mRNAs and CBP80/20 is replaced by the cytoplasmic cap-binding protein eIF4E. Steady-state translation directed by eIF4E allows for an immediate and rapid response to changes in physiological conditions. Here, we show that nonsense-mediated mRNA decay (NMD), which restricts only to the pioneer round of translation but not to steady-state translation, efficiently occurs even during serum starvation, in which steady-state translation is drastically abolished. Accordingly, CBP80 remains in the nucleus and processing bodies are unaffected in their abundance and number in serum-starved conditions. These results suggest that mRNAs enter the pioneer round of translation during serum starvation and are targeted for NMD if they contain premature termination codons

  18. A role for auxin redistribution in the responses of the root system architecture to phosphate starvation in Arabidopsis.

    Science.gov (United States)

    Nacry, Philippe; Canivenc, Geneviève; Muller, Bertrand; Azmi, Abdelkrim; Van Onckelen, Harry; Rossignol, Michel; Doumas, Patrick

    2005-08-01

    The changes in root system architecture (RSA) triggered by phosphate (P) deprivation were studied in Arabidopsis (Arabidopsis thaliana) plants grown for 14 d on 1 mM or 3 microM P. Two different temporal phases were observed in the response of RSA to low P. First, lateral root (LR) development was promoted between days 7 and 11 after germination, but, after day 11, all root growth parameters were negatively affected, leading to a general reduction of primary root (PR) and LR lengths and of LR density. Low P availability had contrasting effects on various stages of LR development, with a marked inhibition of primordia initiation but a strong stimulation of activation of the initiated primordia. The involvement of auxin signaling in these morphological changes was investigated in wild-type plants treated with indole-3-acetic acid or 2,3,5-triiodobenzoic acid and in axr4-1, aux1-7, and eir1-1 mutants. Most effects of low P on RSA were dramatically modified in the mutants or hormone-treated wild-type plants. This shows that auxin plays a major role in the P starvation-induced changes of root development. From these data, we hypothesize that several aspects of the RSA response to low P are triggered by local modifications of auxin concentration. A model is proposed that postulates that P starvation results in (1) an overaccumulation of auxin in the apex of the PR and in young LRs, (2) an overaccumulation of auxin or a change in sensitivity to auxin in the lateral primordia, and (3) a decrease in auxin concentration in the lateral primordia initiation zone of the PR and in old laterals. Measurements of local changes in auxin concentrations induced by low P, either by direct quantification or by biosensor expression pattern (DR5::beta-glucuronidase reporter gene), are in line with these hypotheses. Furthermore, the observation that low P availability mimicked the action of auxin in promoting LR development in the alf3 mutant confirmed that P starvation stimulates

  19. Influence of starvation, triton WR-1339 and [131I]-human serum albumin on rat liver lysosomes

    International Nuclear Information System (INIS)

    Harikumar, P.; Ninjoor, V.

    1986-01-01

    The response of rat liver lysosomes to starvation and administration of lysosomotropic agents viz. Triton WR-1339 and [ 131 I]-human serum albumin, was assessed in terms of their distribution pattern after isopycnic sucrose density gradient centrifugation. Starvation induced changes in lysosomes appeared to be similar to that produced by the detergent uptake. Both the treatments caused a distinct decline in the equilibration densities of the organelles. On the other hand, injected labelled protein failed to comigrate with the lysosomal markers in starved as well as Triton treated rats and conspicuously remained in a region of high specific gravity in the gradient. These findings indicate retarded fusion between secondary lysosomes and [ 131 I]-human serum albumin containing phagosomes in the livers of rats subjected to starvation or detergent treatment. (author)

  20. Transforming Growth Factor β/Activin signaling in neurons increases susceptibility to starvation.

    Directory of Open Access Journals (Sweden)

    Wen-Bin Alfred Chng

    Full Text Available Animals rely on complex signaling network to mobilize its energy stores during starvation. We have previously shown that the sugar-responsive TGFβ/Activin pathway, activated through the TGFβ ligand Dawdle, plays a central role in shaping the post-prandial digestive competence in the Drosophila midgut. Nevertheless, little is known about the TGFβ/Activin signaling in sugar metabolism beyond the midgut. Here, we address the importance of Dawdle (Daw after carbohydrate ingestion. We found that Daw expression is coupled to dietary glucose through the evolutionarily conserved Mio-Mlx transcriptional complex. In addition, Daw activates the TGFβ/Activin signaling in neuronal populations to regulate triglyceride and glycogen catabolism and energy homeostasis. Loss of those neurons depleted metabolic reserves and rendered flies susceptible to starvation.

  1. Transforming Growth Factor β/Activin signaling in neurons increases susceptibility to starvation.

    Science.gov (United States)

    Chng, Wen-Bin Alfred; Koch, Rafael; Li, Xiaoxue; Kondo, Shu; Nagoshi, Emi; Lemaitre, Bruno

    2017-01-01

    Animals rely on complex signaling network to mobilize its energy stores during starvation. We have previously shown that the sugar-responsive TGFβ/Activin pathway, activated through the TGFβ ligand Dawdle, plays a central role in shaping the post-prandial digestive competence in the Drosophila midgut. Nevertheless, little is known about the TGFβ/Activin signaling in sugar metabolism beyond the midgut. Here, we address the importance of Dawdle (Daw) after carbohydrate ingestion. We found that Daw expression is coupled to dietary glucose through the evolutionarily conserved Mio-Mlx transcriptional complex. In addition, Daw activates the TGFβ/Activin signaling in neuronal populations to regulate triglyceride and glycogen catabolism and energy homeostasis. Loss of those neurons depleted metabolic reserves and rendered flies susceptible to starvation.

  2. Oxidative Stress-Induced Dysfunction of Muller Cells During Starvation

    DEFF Research Database (Denmark)

    Toft-Kehler, Anne Katrine; Gurubaran, Iswariyaraja Sridevi; Madsen, Claus Desler

    2016-01-01

    starvation for 24 hours. Effects of starvation and H2O2 on glutamate uptake and mitochondrial function were assessed by kinetic glutamate uptake assays and Seahorse assays, respectively. Cell survival was evaluated by cell viability assays. mRNA and protein expressions were assessed by quantitative PCR...

  3. The role of carbon starvation in the induction of enzymes that degrade plant-derived carbohydrates in Aspergillus niger.

    Science.gov (United States)

    van Munster, Jolanda M; Daly, Paul; Delmas, Stéphane; Pullan, Steven T; Blythe, Martin J; Malla, Sunir; Kokolski, Matthew; Noltorp, Emelie C M; Wennberg, Kristin; Fetherston, Richard; Beniston, Richard; Yu, Xiaolan; Dupree, Paul; Archer, David B

    2014-11-01

    Fungi are an important source of enzymes for saccharification of plant polysaccharides and production of biofuels. Understanding of the regulation and induction of expression of genes encoding these enzymes is still incomplete. To explore the induction mechanism, we analysed the response of the industrially important fungus Aspergillus niger to wheat straw, with a focus on events occurring shortly after exposure to the substrate. RNA sequencing showed that the transcriptional response after 6h of exposure to wheat straw was very different from the response at 24h of exposure to the same substrate. For example, less than half of the genes encoding carbohydrate active enzymes that were induced after 24h of exposure to wheat straw, were also induced after 6h exposure. Importantly, over a third of the genes induced after 6h of exposure to wheat straw were also induced during 6h of carbon starvation, indicating that carbon starvation is probably an important factor in the early response to wheat straw. The up-regulation of the expression of a high number of genes encoding CAZymes that are active on plant-derived carbohydrates during early carbon starvation suggests that these enzymes could be involved in a scouting role during starvation, releasing inducing sugars from complex plant polysaccharides. We show, using proteomics, that carbon-starved cultures indeed release CAZymes with predicted activity on plant polysaccharides. Analysis of the enzymatic activity and the reaction products, indicates that these proteins are enzymes that can degrade various plant polysaccharides to generate both known, as well as potentially new, inducers of CAZymes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Inhibition of CLIC4 enhances autophagy and triggers mitochondrial and ER stress-induced apoptosis in human glioma U251 cells under starvation.

    Directory of Open Access Journals (Sweden)

    Jiateng Zhong

    Full Text Available CLIC4/mtCLIC, a chloride intracellular channel protein, localizes to mitochondria, endoplasmic reticulum (ER, nucleus and cytoplasm, and participates in the apoptotic response to stress. Apoptosis and autophagy, the main types of the programmed cell death, seem interconnected under certain stress conditions. However, the role of CLIC4 in autophagy regulation has yet to be determined. In this study, we demonstrate upregulation and nuclear translocation of the CLIC4 protein following starvation in U251 cells. CLIC4 siRNA transfection enhanced autophagy with increased LC3-II protein and puncta accumulation in U251 cells under starvation conditions. In that condition, the interaction of the 14-3-3 epsilon isoform with CLIC4 was abolished and resulted in Beclin 1 overactivation, which further activated autophagy. Moreover, inhibiting the expression of CLIC4 triggered both mitochondrial apoptosis involved in Bax/Bcl-2 and cytochrome c release under starvation and endoplasmic reticulum stress-induced apoptosis with CHOP and caspase-4 upregulation. These results demonstrate that CLIC4 nuclear translocation is an integral part of the cellular response to starvation. Inhibiting the expression of CLIC4 enhances autophagy and contributes to mitochondrial and ER stress-induced apoptosis under starvation.

  5. Starvation and recovery in the deep-sea methanotroph Methyloprofundus sedimenti

    OpenAIRE

    Tavormina, Patricia L.; Kellermann, Matthias Y.; Antony, Chakkiath Paul; Tocheva, Elitza I.; Dalleska, Nathan F.; Jensen, Ashley J.; Valentine, David L.; Hinrichs, Kai-Uwe; Jensen, Grant J.; Dubilier, Nicole; Orphan, Victoria J.

    2017-01-01

    In the deep ocean, the conversion of methane into derived carbon and energy drives the establishment of diverse faunal communities. Yet specific biological mechanisms underlying the introduction of methane-derived carbon into the food web remain poorly described, due to a lack of cultured representative deep-sea methanotrophic prokaryotes. Here, the response of the deep-sea aerobic methanotroph Methyloprofundus sedimenti to methane starvation and recovery was characterized. By combining lipid...

  6. Growth and physiological response of tomato plants to different periods of nitrogen starvation and recovery

    NARCIS (Netherlands)

    Martinez, V.; Amor, del F.M.; Marcelis, L.F.M.

    2005-01-01

    Young, vegetative-state tomato plants, starved of N for 1, 3 or 7 d, followed, in each case, by a 7-d recovery period with nutrient solution containing N, were examined. Relative growth rate (RGR), leaf photosynthesis and leaf expansion were reduced after only 1 d of N starvation.Tissue N

  7. Evidence for the Adverse Effect of Starvation on Bone Quality: A Review of the Literature

    Directory of Open Access Journals (Sweden)

    Janina Kueper

    2015-01-01

    Full Text Available Malnutrition and starvation’s possible adverse impacts on bone health and bone quality first came into the spotlight after the horrors of the Holocaust and the ghettos of World War II. Famine and food restrictions led to a mean caloric intake of 200–800 calories a day in the ghettos and concentration camps, resulting in catabolysis and starvation of the inhabitants and prisoners. Severely increased risks of fracture, poor bone mineral density, and decreased cortical strength were noted in several case series and descriptive reports addressing the medical issues of these individuals. A severe effect of severely diminished food intake and frequently concomitant calcium- and Vitamin D deficiencies was subsequently proven in both animal models and the most common cause of starvation in developed countries is anorexia nervosa. This review attempts to summarize the literature available on the impact of the metabolic response to Starvation on overall bone health and bone quality.

  8. Tropical Drosophila ananassae of wet-dry seasons show cross resistance to heat, drought and starvation

    Directory of Open Access Journals (Sweden)

    Chanderkala Lambhod

    2017-11-01

    Full Text Available Plastic responses to multiple environmental stressors in wet or dry seasonal populations of tropical Drosophila species have received less attention. We tested plastic effects of heat hardening, acclimation to drought or starvation, and changes in trehalose, proline and body lipids in Drosophila ananassae flies reared under wet or dry season-specific conditions. Wet season flies revealed significant increase in heat knockdown, starvation resistance and body lipids after heat hardening. However, accumulation of proline was observed only after desiccation acclimation of dry season flies while wet season flies elicited no proline but trehalose only. Therefore, drought-induced proline can be a marker metabolite for dry-season flies. Further, partial utilization of proline and trehalose under heat hardening reflects their possible thermoprotective effects. Heat hardening elicited cross-protection to starvation stress. Stressor-specific accumulation or utilization as well as rates of metabolic change for each energy metabolite were significantly higher in wet-season flies than dry-season flies. Energy metabolite changes due to inter-related stressors (heat versus desiccation or starvation resulted in possible maintenance of energetic homeostasis in wet- or dry-season flies. Thus, low or high humidity-induced plastic changes in energy metabolites can provide cross-protection to seasonally varying climatic stressors.

  9. Adaptation of intestinal hydrolases to starvation in rats: effect of thyroid function

    DEFF Research Database (Denmark)

    Galluser, M; Belkhou, R; Freund, J N

    1991-01-01

    The effects of long-term starvation on the activities of sucrase, lactase, and aminopeptidase, and on their respective mRNA were determined in the small intestine of thyroidectomized and sham-operated adult rats. Thyroidectomy reduced the protein loss at the level of the intestinal brush border...... membranes during starvation. Prolonged fasting caused a significant decrease in sucrase activity, but thyroidectomy partly prevented this effect. However, the amount of the corresponding mRNA dropped during long term starvation without incidence of thyroidectomy. Lactase activity in the brush border...... membranes was increased by starvation, and thyroidectomy caused a further elevation of the enzyme activity. Simultaneously, lactase mRNA content rose only slightly compared to the enzyme activity. Aminopeptidase activity and mRNA content decreased during starvation and thyroidectomy did not prevent...

  10. Biofilm extracellular polysaccharides degradation during starvation and enamel demineralization.

    Directory of Open Access Journals (Sweden)

    Bárbara Emanoele Costa Oliveira

    Full Text Available This study was conducted to evaluate if extracellular polysaccharides (EPS are used by Streptococcus mutans (Sm biofilm during night starvation, contributing to enamel demineralization increasing occurred during daily sugar exposure. Sm biofilms were formed during 5 days on bovine enamel slabs of known surface hardness (SH. The biofilms were exposed to sucrose 10% or glucose + fructose 10.5% (carbohydrates that differ on EPS formation, 8x/day but were maintained in starvation during the night. Biofilm samples were harvested during two moments, on the end of the 4th day and in the morning of the 5th day, conditions of sugar abundance and starvation, respectively. The slabs were also collected to evaluate the percentage of surface hardness loss (%SHL. The biofilms were analyzed for EPS soluble and insoluble and intracellular polysaccharides (IPS, viable bacteria (CFU, biofilm architecture and biomass. pH, calcium and acid concentration were determined in the culture medium. The data were analyzed by two-way ANOVA followed by Tukey's test or Student's t-test. The effect of the factor carbohydrate treatment for polysaccharide analysis was significant (p 0.05. Larger amounts of soluble and insoluble EPS and IPS were formed in the sucrose group when compared to glucose + fructose group (p < 0.05, but they were not metabolized during starvation time (S-EPS, p = 0.93; I-EPS, p = 0.11; and IPS = 0.96. Greater enamel %SHL was also found for the sucrose group (p < 0.05 but the demineralization did not increase during starvation (p = 0.09. In conclusion, the findings suggest that EPS metabolization by S. mutans during night starvation do not contribute to increase enamel demineralization occurred during the daily abundance of sugar.

  11. Unravelling the cross-talk between iron starvation and oxidative stress responses highlights the key role of PerR (alr0957) in peroxide signalling in the cyanobacterium Nostoc PCC 7120.

    Science.gov (United States)

    Yingping, Fan; Lemeille, Sylvain; Talla, Emmanuel; Janicki, Annick; Denis, Yann; Zhang, Cheng-Cai; Latifi, Amel

    2014-10-01

    The cyanobacterial phylum includes oxygenic photosynthetic prokaryotes of a wide variety of morphologies, metabolisms and ecologies. Their adaptation to their various ecological niches is mainly achieved by sophisticated regulatory mechanisms and depends on a fine cross-talk between them. We assessed the global transcriptomic response of the filamentous cyanobacterium Nostoc PCC 7120 to iron starvation and oxidative stress. More than 20% of the differentially expressed genes in response to iron stress were also responsive to oxidative stress. These transcripts include antioxidant proteins-encoding genes that confirms that iron depletion leads to reactive oxygen accumulation. The activity of the Fe-superoxide dismutase was not significantly decreased under iron starvation, indicating that the oxidative stress generated under iron deficiency is not a consequence of (SOD) deficiency. The transcriptional data indicate that the adaptation of Nostoc to iron-depleted conditions displays important differences with what has been shown in unicellular cyanobacteria. While the FurA protein that regulates the response to iron deprivation has been well characterized in Nostoc, the regulators in charge of the oxidative stress response are unknown. Our study indicates that the alr0957 (perR) gene encodes the master regulator of the peroxide stress. PerR is a peroxide-sensor repressor that senses peroxide by metal-catalysed oxidation.

  12. Nitrogen excretion in rats on a protein-free diet and during starvation

    DEFF Research Database (Denmark)

    Chwalibog, André; Sawosz, Ewa; Niemiec, Tomasz

    2008-01-01

    Nitrogen balances (six days) were determined in male Wistar rats during feeding a diet with sufficient protein or a nearly protein-free diet (n = 2 x 24), and then during three days of starvation (n = 2 x 12). The objective was to evaluate the effect of protein withdrawal on minimum nitrogen...... excretion in urine (UN), corresponding to endogenous UN, during feeding and subsequent starvation periods. The rats fed the protein free-diet had almost the same excretion of urinary N during feeding and starvation (165 and 157 mg/kg W(0.75)), while it was 444 mg/kg W(0.75) in rats previously fed...... with protein, demonstrating a major influence of protein content in a diet on N excretion during starvation. Consequently, the impact of former protein supply on N losses during starvation ought to be considered when evaluating minimum N requirement necessary to sustain life....

  13. A Phosphate Starvation-Inducible Ribonuclease of Bacillus licheniformis.

    Science.gov (United States)

    Nguyen, Thanh Trung; Nguyen, Minh Hung; Nguyen, Huy Thuan; Nguyen, Hoang Anh; Le, Thi Hoi; Schweder, Thomas; Jürgen, Britta

    2016-08-28

    The BLi03719 protein of Bacillus licheniformis DSM13 belongs to the most abundant extracellular proteins under phosphate starvation conditions. In this study, the function of this phosphate starvation inducible protein was determined. An amino-acid sequence analysis of the BLi03719-encoding gene showed a high similarity with genes encoding the barnase of Bacillus amyloliquefaciens FZB42 and binase-like RNase of Bacillus pumilus SARF-032. The comparison of the control strain and a BLi03719-deficient strain revealed a strongly reduced extracellular ribonuclease activity of the mutant. Furthermore, this knockout mutant exhibited delayed growth with yeast RNA as an alternative phosphate and carbon source. These results suggest that BLi03719 is an extracellular ribonuclease expressed in B. licheniformis under phosphate starvation conditions. Finally, a BLi03719 mutant showed an advantageous effect on the overexpression of the heterologous amyE gene under phosphate-limited growth conditions.

  14. Changes in Hematological, Biochemical and Non-specific Immune Parameters of Olive Flounder, , Following Starvation

    Directory of Open Access Journals (Sweden)

    Jong-Hyun Kim

    2014-09-01

    Full Text Available Triplicate groups of fed and starved olive flounder, Paralichthys olivaceus (body weight: 119.8±17.46 g, were examined over 42 days for physiological changes using hematological, biochemical, and non-specific immune parameters. No significant differences in concentrations of blood hemoglobin and hematocrit and plasma levels of total cholesterol, aspartate aminotransferase, alanine aminotransferase, glucose, and cortisol were detected between fed and starved groups at any sampling time throughout the experiment. In contrast, plasma total protein concentrations were significantly lower in starved fish than in fed fish from day 7 onwards. Moreover, plasma lysozyme concentrations were significantly higher in starved flounder from day 21 onwards. This result confirms that the response of olive flounder to short-term (less than about 1.5 months starvation consists of a readjustment of metabolism rather than the activation of an alarm-stress response. The present results indicate that starvation does not significantly compromise the health status of fish despite food limitation.

  15. A comparison of the transcriptome of Drosophila melanogaster in response to entomopathogenic fungus, ionizing radiation, starvation and cold shock.

    Science.gov (United States)

    Moskalev, Alexey; Zhikrivetskaya, Svetlana; Krasnov, George; Shaposhnikov, Mikhail; Proshkina, Ekaterina; Borisoglebsky, Dmitry; Danilov, Anton; Peregudova, Darya; Sharapova, Irina; Dobrovolskaya, Eugenia; Solovev, Ilya; Zemskaya, Nadezhda; Shilova, Lyubov; Snezhkina, Anastasia; Kudryavtseva, Anna

    2015-01-01

    The molecular mechanisms that determine the organism's response to a variety of doses and modalities of stress factors are not well understood. We studied effects of ionizing radiation (144, 360 and 864 Gy), entomopathogenic fungus (10 and 100 CFU), starvation (16 h), and cold shock (+4, 0 and -4°C) on an organism's viability indicators (survival and locomotor activity) and transcriptome changes in the Drosophila melanogaster model. All stress factors but cold shock resulted in a decrease of lifespan proportional to the dose of treatment. However, stress-factors affected locomotor activity without correlation with lifespan. Our data revealed both significant similarities and differences in differential gene expression and the activity of biological processes under the influence of stress factors. Studied doses of stress treatments deleteriously affect the organism's viability and lead to different changes of both general and specific cellular stress response mechanisms.

  16. NblA1/A2-Dependent Homeostasis of Amino Acid Pools during Nitrogen Starvation in Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Kiyota, Hiroshi; Hirai, Masami Yokota; Ikeuchi, Masahiko

    2014-06-30

    Nutrient balance is important for photosynthetic growth and biomass production in microalgae. Here, we investigated and compared metabolic responses of amino acid pools to nitrogen and sulfur starvation in a unicellular model cyanobacterium, Synechocystis sp. PCC 6803, and its mutant nblA1/A2. It is known that NblA1/A2-dependent and -independent breakdown of abundant photosynthetic phycobiliproteins and other cellular proteins supply nutrients to the organism. However, the contribution of the NblA1/A2-dependent nutrient supply to amino acid pool homeostasis has not been studied. Our study demonstrates that changes in the pool size of many amino acids during nitrogen starvation can be categorized as NblA1/A2-dependent (Gln, Glu, glutathione, Gly, Ile, Leu, Met, Phe, Pro, Ser, Thr, Tyr and Val) and NblA1/A2-independent (Ala, Asn, Lys, and Trp). We also report unique changes in amino acid pool sizes during sulfur starvation in wild type and the mutant and found a generally marked increase in the Lys pool in cyanobacteria during nutrient starvation. In conclusion, the NblA1/A2-dependent protein turnover contributes to the maintenance of many amino acid pools during nitrogen starvation.

  17. NblA1/A2-Dependent Homeostasis of Amino Acid Pools during Nitrogen Starvation in Synechocystis sp. PCC 6803

    Directory of Open Access Journals (Sweden)

    Hiroshi Kiyota

    2014-06-01

    Full Text Available Nutrient balance is important for photosynthetic growth and biomass production in microalgae. Here, we investigated and compared metabolic responses of amino acid pools to nitrogen and sulfur starvation in a unicellular model cyanobacterium, Synechocystis sp. PCC 6803, and its mutant nblA1/A2. It is known that NblA1/A2-dependent and -independent breakdown of abundant photosynthetic phycobiliproteins and other cellular proteins supply nutrients to the organism. However, the contribution of the NblA1/A2-dependent nutrient supply to amino acid pool homeostasis has not been studied. Our study demonstrates that changes in the pool size of many amino acids during nitrogen starvation can be categorized as NblA1/A2-dependent (Gln, Glu, glutathione, Gly, Ile, Leu, Met, Phe, Pro, Ser, Thr, Tyr and Val and NblA1/A2-independent (Ala, Asn, Lys, and Trp. We also report unique changes in amino acid pool sizes during sulfur starvation in wild type and the mutant and found a generally marked increase in the Lys pool in cyanobacteria during nutrient starvation. In conclusion, the NblA1/A2-dependent protein turnover contributes to the maintenance of many amino acid pools during nitrogen starvation.

  18. Perception of Arabidopsis AtPep peptides, but not bacterial elicitors, accelerates starvation-induced senescence

    Directory of Open Access Journals (Sweden)

    Kay eGully

    2015-01-01

    Full Text Available Members of the AtPep group of Arabidopsis endogenous peptides have frequently been reported to induce pattern-triggered immunity and to increase resistance to diverse pathogens by amplifying the innate immune response. Here, we made the surprising observation that dark-induced leaf senescence was accelerated by the presence of Peps. Adult leaves as well as leaf discs of Col-0 wild type plants showed a Pep-triggered early onset of chlorophyll breakdown and leaf yellowing whereas pepr1 pepr2 double mutant plants were insensitive. In addition, this response was dependent on ethylene signaling and inhibited by the addition of cytokinins. Notably, addition of the bacterial elicitors flg22 or elf18, both potent inducers of pattern-triggered immunity, did not provoke an early onset of leaf senescence.Continuous darkness leads to energy deprivation and starvation and therewith promotes leaf senescence. We found that continuous darkness also strongly induced PROPEP3 transcription. Moreover, Pep-perception led to a rapid induction of PAO, APG7 and APG8a, genes indispensable for chlorophyll degradation as well as autophagy, respectively, and all three hallmarks of starvation and senescence. Notably, addition of sucrose as a source of energy inhibited the Pep-triggered early onset of senescence. In conclusion, we report that Pep-perception accelerates dark/starvation-induced senescence via an early induction of chlorophyll degradation and autophagy. This represents a novel and unique characteristic of PEPR signaling, unrelated to pattern-triggered immunity.

  19. Impact of starvation on survival, meat condition and metabolism of Chlamys farreri

    Science.gov (United States)

    Yang, Hong-Sheng; Wang, Jian; Zhou, Yi; Wang, Ping; He, Yi-Chao; Zhang, Fu-Sui

    2001-03-01

    The effects of 60-day starvation on survival rate, condition index (CI), changes of nutrient composition of different tissues, respiration and excretion of scallop Chlamys farreri were studied in laboratory from Oct. 17 to Dec. 15, 1997. Two groups (control and starvation with 200 individuals each) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 17°C. Starvation effects were measured after 10, 20, 40 and 60 days. There was no mass mortality of scallops of the two tanks and survival rates of the control and starvation groups were 93.5% and 92.0%, respectively. Starvation had strong effect on the meat condition of the scallops, especially after 10 days; when relative lipid percentage dropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption rate (OCR) and the ammonia-N excretion rate (AER) was obvious. The OCR increased rapidly after 10 days but decreased after 20 days. The AER increased after 10 days and 20 days, but decreased obviously from 20 to 40 days. The O∶N ratios varied to different degrees, and minimized after 20 days. The low O∶N ratios implied that the protein was the main material for the metabolism of C. farreri.

  20. Effects of intestinal bacteria-derived p-cresyl sulfate on Th1-type immune response in vivo and in vitro

    International Nuclear Information System (INIS)

    Shiba, Takahiro; Kawakami, Koji; Sasaki, Takashi; Makino, Ikuyo; Kato, Ikuo; Kobayashi, Toshihide; Uchida, Kazumi; Kaneko, Kimiyuki

    2014-01-01

    Protein fermentation by intestinal bacteria generates various compounds that are not synthesized by their hosts. An example is p-cresol, which is produced from tyrosine. Patients with chronic kidney disease (CKD) accumulate high concentrations of intestinal bacteria-derived p-cresyl sulfate (pCS), which is the major metabolite of p-cresol, in their blood, and this accumulation contributes to certain CKD-associated disorders. Immune dysfunction is a CKD-associated disorder that frequently contributes to infectious diseases among CKD patients. Although some studies imply pCS as an etiological factor, the relation between pCS and immune systems is poorly understood. In the present study, we investigated the immunological effects of pCS derived from intestinal bacteria in mice. For this purpose, we fed mice a tyrosine-rich diet that causes the accumulation of pCS in their blood. The mice were shown to exhibit decreased Th1-driven 2, 4-dinitrofluorobenzene-induced contact hypersensitivity response. The concentration of pCS in blood was negatively correlated with the degree of the contact hypersensitivity response. In contrast, the T cell-dependent antibody response was not influenced by the accumulated pCS. We also examined the in vitro cytokine responses by T cells in the presence of pCS. The production of IFN-γ was suppressed by pCS. Further, pCS decreased the percentage of IFN-γ-producing Th1 cells. Our results suggest that intestinal bacteria-derived pCS suppressesTh1-type cellular immune responses. - Highlights: • Mice fed a tyrosine-rich diet accumulated p-cresyl sulfate in their blood. • p-Cresyl sulfate negatively correlated with contact hypersensitivity response. • The in vitro production of IFN-γ was suppressed by p-cresyl sulfate. • p-Cresyl sulfate decreased the percentage of IFN-γ-producing Th1 cells in vitro

  1. Effects of intestinal bacteria-derived p-cresyl sulfate on Th1-type immune response in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Shiba, Takahiro, E-mail: takahiro-shiba@yakult.co.jp; Kawakami, Koji; Sasaki, Takashi; Makino, Ikuyo; Kato, Ikuo; Kobayashi, Toshihide; Uchida, Kazumi; Kaneko, Kimiyuki

    2014-01-15

    Protein fermentation by intestinal bacteria generates various compounds that are not synthesized by their hosts. An example is p-cresol, which is produced from tyrosine. Patients with chronic kidney disease (CKD) accumulate high concentrations of intestinal bacteria-derived p-cresyl sulfate (pCS), which is the major metabolite of p-cresol, in their blood, and this accumulation contributes to certain CKD-associated disorders. Immune dysfunction is a CKD-associated disorder that frequently contributes to infectious diseases among CKD patients. Although some studies imply pCS as an etiological factor, the relation between pCS and immune systems is poorly understood. In the present study, we investigated the immunological effects of pCS derived from intestinal bacteria in mice. For this purpose, we fed mice a tyrosine-rich diet that causes the accumulation of pCS in their blood. The mice were shown to exhibit decreased Th1-driven 2, 4-dinitrofluorobenzene-induced contact hypersensitivity response. The concentration of pCS in blood was negatively correlated with the degree of the contact hypersensitivity response. In contrast, the T cell-dependent antibody response was not influenced by the accumulated pCS. We also examined the in vitro cytokine responses by T cells in the presence of pCS. The production of IFN-γ was suppressed by pCS. Further, pCS decreased the percentage of IFN-γ-producing Th1 cells. Our results suggest that intestinal bacteria-derived pCS suppressesTh1-type cellular immune responses. - Highlights: • Mice fed a tyrosine-rich diet accumulated p-cresyl sulfate in their blood. • p-Cresyl sulfate negatively correlated with contact hypersensitivity response. • The in vitro production of IFN-γ was suppressed by p-cresyl sulfate. • p-Cresyl sulfate decreased the percentage of IFN-γ-producing Th1 cells in vitro.

  2. Effects of Starvation and Thermal Stress on the Thermal Tolerance of Silkworm, Bombyx mori: Existence of Trade-offs and Cross-Tolerances.

    Science.gov (United States)

    Mir, A H; Qamar, A

    2017-09-27

    Organisms, in nature, are often subjected to multiple stressors, both biotic and abiotic. Temperature and starvation are among the main stressors experienced by organisms in their developmental cycle and the responses to these stressors may share signaling pathways, which affects the way these responses are manifested. Temperature is a major factor governing the performance of ectothermic organisms in ecosystems worldwide and, therefore, the thermal tolerance is a central issue in the thermobiology of these organisms. Here, we investigated the effects of starvation as well as mild heat and cold shocks on the thermal tolerance of the larvae of silkworm, Bombyx mori (Linnaeus). Starvation acted as a meaningful or positive stressor as it improved cold tolerance, measured as chill coma recovery time (CCRT), but, at the same time, it acted as a negative stressor and impaired the heat tolerance, measured as heat knockdown time (HKT). In the case of heat tolerance, starvation negated the positive effects of both mild cold as well as mild heat shocks and thus indicated the existence of trade-off between these stressors. Both mild heat and cold shocks improved the thermal tolerance, but the effects were more prominent when the indices were measured in response to a stressor of same type, i.e., a mild cold shock improved the cold tolerance more than the heat tolerance and vice versa. This improvement in thermal tolerance by both mild heat as well as cold shocks indicated the possibility of cross-tolerance between these stressors.

  3. Growth performance and root transcriptome remodeling of Arabidopsis in response to Mars-like levels of magnesium sulfate.

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    Anne M Visscher

    Full Text Available BACKGROUND: Martian regolith (unconsolidated surface material is a potential medium for plant growth in bioregenerative life support systems during manned missions on Mars. However, hydrated magnesium sulfate mineral levels in the regolith of Mars can reach as high as 10 wt%, and would be expected to be highly inhibitory to plant growth. METHODOLOGY AND PRINCIPAL FINDINGS: Disabling ion transporters AtMRS2-10 and AtSULTR1;2, which are plasma membrane localized in peripheral root cells, is not an effective way to confer tolerance to magnesium sulfate soils. Arabidopsis mrs2-10 and sel1-10 knockout lines do not mitigate the growth inhibiting impacts of high MgSO(4.7H(2O concentrations observed with wildtype plants. A global approach was used to identify novel genes with potential to enhance tolerance to high MgSO(4.7H(2O (magnesium sulfate stress. The early Arabidopsis root transcriptome response to elevated concentrations of magnesium sulfate was characterized in Col-0, and also between Col-0 and the mutant line cax1-1, which was confirmed to be relatively tolerant of high levels of MgSO(4.7H(2O in soil solution. Differentially expressed genes in Col-0 treated for 45 min. encode enzymes primarily involved in hormone metabolism, transcription factors, calcium-binding proteins, kinases, cell wall related proteins and membrane-based transporters. Over 200 genes encoding transporters were differentially expressed in Col-0 up to 180 min. of exposure, and one of the first down-regulated genes was CAX1. The importance of this early response in wildtype Arabidopsis is exemplified in the fact that only four transcripts were differentially expressed between Col-0 and cax1-1 at 180 min. after initiation of treatment. CONCLUSIONS/SIGNIFICANCE: The results provide a solid basis for the understanding of the metabolic response of plants to elevated magnesium sulfate soils; it is the first transcriptome analysis of plants in this environment. The results foster

  4. Effects of starvation on intermolt development in Calanus finmarchicus copepodites: a comparison between theoretical models and field studies1

    Science.gov (United States)

    Crain, Jennifer A.; Miller, Charles B.

    Campbell et al . (Deep Sea Research II, 48 (2001) 531) have shown that there was a localized starvation event affecting Calanus finmarchicus on the southern flank of Georges Bank in April 1997. Growth and molting rates of this dominant copepod were reduced. We have used the morphology of tooth development in field-collected samples to show that this starvation affected animals living continuously in the field, as well as those in Campbell et al .'s experimental tanks. Assuming a point of reserve saturation (PRS) response of Calanus to food limitation, and correspondence between PRS and advance from the postmolt jaw facies, the proportion of individuals with postmolt jaws should increase in all copepodite stages under starvation. Individuals that have developed past PRS should molt to the next stage, acquiring postmolt facies. Thus, the fraction of postmolt jaws should increase, while the fraction of jaws in later phases should decrease. This was observed for a drifter-marked station over five days. Numerical simulations of jaw phase distributions expected under full nutrition, and both total and patchy starvation were generated from individual-based models of development. Proportions of copepodites in postmolt phase do not increase with full nutrition. A simulation of a total starvation event showed a marked increase in postmolts during food limitation, but the increase was more extreme than the field data. A modification of the starvation simulation, representing patchy feeding conditions, matched the level of increase of postmolt individuals in all stages that was observed in the field samples.

  5. Effects of heat stress and starvation on clonal odontoblast-like cells.

    Science.gov (United States)

    Morotomi, Takahiko; Kitamura, Chiaki; Toyono, Takashi; Okinaga, Toshinori; Washio, Ayako; Saito, Noriko; Nishihara, Tatsuji; Terashita, Masamichi; Anan, Hisashi

    2011-07-01

    Heat stress during restorative procedures, particularly under severe starvation conditions, can trigger damage to dental pulp. In the present study, we examined effects of heat stress on odontoblastic activity and inflammatory responses in an odontoblast-like cell line (KN-3) under serum-starved conditions. Viability, nuclear structures, and inflammatory responses of KN-3 cells were examined in culture medium containing 10% or 1% serum after exposure to heat stress at 43°C for 45 minutes. Gene expression of extracellular matrices, alkaline phosphatase activity, and detection of extracellular calcium deposition in cells exposed to heat stress were also examined. Reduced viability and apoptosis were transiently induced in KN-3 cells during the initial phases after heat stress; thereafter, cells recovered their viability. The cytotoxic effects of heat stress were enhanced under serum-starved conditions. Heat stress also strongly up-regulated expression of heat shock protein 25 as well as transient expression of tumor necrosis factor-alpha, interleukin-6, and cyclooxygenase-2 in KN-3 cells. In contrast, expression of type-1 collagen, runt-related transcription factor 2, and dentin sialophosphoprotein were not inhibited by heat stress although starvation suppressed ALP activity and delayed progression of calcification. Odontoblast-like cells showed thermoresistance with transient inflammatory responses and without loss of calcification activity, and their thermoresistance and calcification activity were influenced by nutritional status. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Thermophilic Sulfate-Reducing Bacteria in Cold Marine Sediment

    DEFF Research Database (Denmark)

    ISAKSEN, MF; BAK, F.; JØRGENSEN, BB

    1994-01-01

    sulfate-reducing bacteria was detected. Time course experiments showed constant sulfate reduction rates at 4 degrees C and 30 degrees C, whereas the activity at 60 degrees C increased exponentially after a lag period of one day. Thermophilic, endospore-forming sulfate-reducing bacteria, designated strain...... C to search for presence of psychrophilic, mesophilic and thermophilic sulfate-reducing bacteria. Detectable activity was initially only in the mesophilic range, but after a lag phase sulfate reduction by thermophilic sulfate-reducing bacteria were observed. No distinct activity of psychrophilic...... P60, were isolated and characterized as Desulfotomaculum kuznetsovii. The temperature response of growth and respiration of strain P60 agreed well with the measured sulfate reduction at 50 degrees-70 degrees C. Bacteria similar to strain P60 could thus be responsible for the measured thermophilic...

  7. Thermophilic Sulfate-Reducing Bacteria in Cold Marine Sediment

    DEFF Research Database (Denmark)

    ISAKSEN, MF; BAK, F.; JØRGENSEN, BB

    1994-01-01

    C to search for presence of psychrophilic, mesophilic and thermophilic sulfate-reducing bacteria. Detectable activity was initially only in the mesophilic range, but after a lag phase sulfate reduction by thermophilic sulfate-reducing bacteria were observed. No distinct activity of psychrophilic...... sulfate-reducing bacteria was detected. Time course experiments showed constant sulfate reduction rates at 4 degrees C and 30 degrees C, whereas the activity at 60 degrees C increased exponentially after a lag period of one day. Thermophilic, endospore-forming sulfate-reducing bacteria, designated strain...... P60, were isolated and characterized as Desulfotomaculum kuznetsovii. The temperature response of growth and respiration of strain P60 agreed well with the measured sulfate reduction at 50 degrees-70 degrees C. Bacteria similar to strain P60 could thus be responsible for the measured thermophilic...

  8. Gastrointestinal and microbial responses to sulfate-supplemented drinking water in mice.

    Science.gov (United States)

    Deplancke, Bart; Finster, Kai; Graham, W Vallen; Collier, Chad T; Thurmond, Joel E; Gaskins, H Rex

    2003-04-01

    There is increasing evidence that hydrogen sulfide (H2S), produced by intestinal sulfate-reducing bacteria (SRB), may be involved in the etiopathogenesis of chronic diseases such as ulcerative colitis and colorectal cancer. The activity of SRB, and thus H2S production, is likely determined by the availability of sulfur-containing compounds in the intestine. However, little is known about the impact of dietary or inorganic sulfate on intestinal sulfate and SRB-derived H2S concentrations. In this study, the effects of short-term (7 day) and long-term (1 year) inorganic sulfate supplementation of the drinking water on gastrointestinal (GI) sulfate and H2S concentrations (and thus activity of resident SRBs), and the density of large intestinal sulfomucin-containing goblet cells, were examined in C3H/HeJBir mice. Additionally, a PCR-denaturing gradient gel electrophoresis (DGGE)-based molecular ecology technique was used to examine the impact of sulfate-amended drinking water on microbial community structure throughout the GI tract. Average H2S concentrations ranged from 0.1 mM (stomach) to 1 mM (cecum). A sulfate reduction assay demonstrated in situ production of H2S throughout the GI tract, confirming the presence of SRB. However, H2S generation and concentrations were greatest in the cecum and colon. Sulfate supplementation of drinking water did not significantly increase intestinal sulfate or H2S concentrations, suggesting that inorganic sulfate is not an important modulator of intestinal H2S concentrations, although it altered the bacterial profiles of the stomach and distal colon of 1-year-old mice. This change in colonic bacterial profiles may reflect a corresponding increase in the density of sulfomucin-containing goblet cells in sulfate-supplemented compared with control mice.

  9. A maize gene encoding an NADPH binding enzyme highly homologous to isoflavone reductases is activated in response to sulfur starvation.

    Science.gov (United States)

    Petrucco, S; Bolchi, A; Foroni, C; Percudani, R; Rossi, G L; Ottonello, S

    1996-01-01

    we isolated a novel gene that is selectively induced both in roots and shoots in response to sulfur starvation. This gene encodes a cytosolic, monomeric protein of 33 kD that selectively binds NADPH. The predicted polypeptide is highly homologous ( > 70%) to leguminous isoflavone reductases (IFRs), but the maize protein (IRL for isoflavone reductase-like) belongs to a novel family of proteins present in a variety of plants. Anti-IRL antibodies specifically recognize IFR polypeptides, yet the maize protein is unable to use various isoflavonoids as substrates. IRL expression is correlated closely to glutathione availability: it is persistently induced in seedlings whose glutathione content is about fourfold lower than controls, and it is down-regulated rapidly when control levels of glutathione are restored. This glutathione-dependent regulation indicates that maize IRL may play a crucial role in the establishment of a thiol-independent response to oxidative stress under glutathione shortage conditions.

  10. Osteoporosis in survivors of early life starvation.

    Science.gov (United States)

    Weisz, George M; Albury, William R

    2013-01-01

    The objective of this study was to provide evidence for the association of early life nutritional deprivation and adult osteoporosis, in order to suggest that a history of such deprivation may be an indicator of increased risk of osteoporosis in later life. The 'fetal programming' of a range of metabolic and cardiovascular disorders in adults was first proposed in the 1990s and more recently extended to disorders of bone metabolism. Localised famines during World War II left populations in whom the long-term effects of maternal, fetal and infantile nutritional deprivation were studied. These studies supported the original concept of 'fetal programming' but did not consider bone metabolism. The present paper offers clinical data from another cohort of World War II famine survivors - those from the Holocaust. The data presented here, specifically addressing the issue of osteoporosis, report on 11 Holocaust survivors in Australia (five females, six males) who were exposed to starvation in early life. The cases show, in addition to other metabolic disorders associated with early life starvation, various levels of osteoporosis, often with premature onset. The cohort studied is too small to support firm conclusions, but the evidence suggests that the risk of adult osteoporosis in both males and females is increased by severe starvation early in life - not just in the period from gestation to infancy but also in childhood and young adulthood. It is recommended that epidemiological research on this issue be undertaken, to assist planning for the future health needs of immigrants to Australia coming from famine affected backgrounds. Pending such research, it would be prudent for primary care health workers to be alert to the prima facie association between early life starvation and adult osteoporosis, and to take this factor into account along with other indicators when assessing a patient's risk of osteoporosis in later life.

  11. A phosphate starvation-driven bidirectional promoter as a potential tool for crop improvement and in vitro plant biotechnology.

    Science.gov (United States)

    Araceli, Oropeza-Aburto; Alfredo, Cruz-Ramírez; Javier, Mora-Macías; Luis, Herrera-Estrella

    2017-05-01

    Phosphate (Pi)-deficient soils are a major limitant factor for crop production in many regions of the world. Despite that plants have innovated several developmental and biochemical strategies to deal with this stress, there are still massive extensions of land which combine several abiotic stresses, including phosphate starvation, that limit their use for plant growth and food production. In several plant species, a genetic programme underlies the biochemical and developmental responses of the organism to cope with low phosphate (Pi) availability. Both protein- and miRNA-coding genes involved in the adaptative response are transcriptionally activated upon Pi starvation. Several of the responsive genes have been identified as transcriptional targets of PHR1, a transcription factor that binds a conserved cis-element called PHR1-binding site (P1BS). Our group has previously described and characterized a minimal genetic arrangement that includes two P1BS elements, as a phosphate-responsive enhancer (EZ2). Here, we report the engineering and successful use of a phosphate-dependent bidirectional promoter, which has been designed and constructed based on the palindromic sequences of the two P1BS elements present in EZ2. This bidirectional promoter has a potential use in both plant in vitro approaches and in the generation of improved crops adapted to Pi starvation and other abiotic stresses. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  12. Developmental acclimation to low or high humidity conditions affect starvation and heat resistance of Drosophila melanogaster.

    Science.gov (United States)

    Parkash, Ravi; Ranga, Poonam; Aggarwal, Dau Dayal

    2014-09-01

    Several Drosophila species originating from tropical humid localities are more resistant to starvation and heat stress than populations from high latitudes but mechanistic bases of such physiological changes are largely unknown. In order to test whether humidity levels affect starvation and heat resistance, we investigated developmental acclimation effects of low to high humidity conditions on the storage and utilization of energy resources, body mass, starvation survival, heat knockdown and heat survival of D. melanogaster. Isofemale lines reared under higher humidity (85% RH) stored significantly higher level of lipids and showed greater starvation survival hours but smaller in body size. In contrast, lines reared at low humidity evidenced reduced levels of body lipids and starvation resistance. Starvation resistance and lipid storage level were higher in females than males. However, the rate of utilization of lipids under starvation stress was lower for lines reared under higher humidity. Adult flies of lines reared at 65% RH and acclimated under high or low humidity condition for 200 hours also showed changes in resistance to starvation and heat but such effects were significantly lower as compared with developmental acclimation. Isofemale lines reared under higher humidity showed greater heat knockdown time and heat-shock survival. These laboratory observations on developmental and adult acclimation effects of low versus high humidity conditions have helped in explaining seasonal changes in resistance to starvation and heat of the wild-caught flies of D. melanogaster. Thus, we may suggest that wet versus drier conditions significantly affect starvation and heat resistance of D. melanogaster. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Expression and activity of sulfate transporters and APS reductase in curly kale in response to sulfate deprivation and re-supply

    NARCIS (Netherlands)

    Koralewska, Aleksandra; Buchner, Peter; Stuiver, C. Elisabeth E.; Posthumus, Freek S.; Kopriva, Stanislav; Hawkesford, Malcolm J.; De Kok, Luit J.

    2009-01-01

    Both activity and expression of sulfate transporters and APS reductase in plants are modulated by the sulfur status of the plant. To examine the regulatory mechanisms in curly kale (Brossica olerracea L.), the sulfate supply was manipulated by the transfer of seedlings to sulfate-deprived

  14. [Starvation ketosis in a breastfeeding woman].

    Science.gov (United States)

    Monnier, D; Goulenok, T; Allary, J; Zarrouk, V; Fantin, B

    2015-12-01

    Bovine ketosis is a rare cause of metabolic acidosis. It is a starvation ketosis that appears in lactating woman. A 29-year-old woman had a previous gastric surgery one month ago while breastfeeding her 6-month child. She presented to emergency with dyspnea, fatigue, weight loss and anorexia. The explorations revealed a serious metabolic acidosis with a high anion gap, for which all other causes have been eliminated. A restrictive diet in lactating patients is a major risk of ketosis or bovine ketosis. Medico-surgical treatment of obesity during lactation seems unreasonable. Breastfeeding should be systematically sought before a medical and surgical management of obesity. With the spread of bariatric surgery, starvation ketosis is a cause of metabolic acidosis not to ignore. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  15. Global gene expression under nitrogen starvation in Xylella fastidiosa: contribution of the σ54 regulon

    Directory of Open Access Journals (Sweden)

    da Silva Neto José F

    2010-08-01

    Full Text Available Abstract Background Xylella fastidiosa, a Gram-negative fastidious bacterium, grows in the xylem of several plants causing diseases such as citrus variegated chlorosis. As the xylem sap contains low concentrations of amino acids and other compounds, X. fastidiosa needs to cope with nitrogen limitation in its natural habitat. Results In this work, we performed a whole-genome microarray analysis of the X. fastidiosa nitrogen starvation response. A time course experiment (2, 8 and 12 hours of cultures grown in defined medium under nitrogen starvation revealed many differentially expressed genes, such as those related to transport, nitrogen assimilation, amino acid biosynthesis, transcriptional regulation, and many genes encoding hypothetical proteins. In addition, a decrease in the expression levels of many genes involved in carbon metabolism and energy generation pathways was also observed. Comparison of gene expression profiles between the wild type strain and the rpoN null mutant allowed the identification of genes directly or indirectly induced by nitrogen starvation in a σ54-dependent manner. A more complete picture of the σ54 regulon was achieved by combining the transcriptome data with an in silico search for potential σ54-dependent promoters, using a position weight matrix approach. One of these σ54-predicted binding sites, located upstream of the glnA gene (encoding glutamine synthetase, was validated by primer extension assays, confirming that this gene has a σ54-dependent promoter. Conclusions Together, these results show that nitrogen starvation causes intense changes in the X. fastidiosa transcriptome and some of these differentially expressed genes belong to the σ54 regulon.

  16. ScFv anti-heparan sulfate antibodies unexpectedly activate endothelial and cancer cells through p38 MAPK: implications for antibody-based targeting of heparan sulfate proteoglycans in cancer.

    Directory of Open Access Journals (Sweden)

    Helena C Christianson

    Full Text Available Tumor development requires angiogenesis and anti-angiogenic therapies have been introduced in the treatment of cancer. In this context, heparan sulfate proteoglycans (HSPGs emerge as interesting targets, owing to their function as co-receptors of major, pro-angiogenic factors. Accordingly, previous studies have suggested anti-tumor effects of heparin, i.e. over-sulfated HS, and various heparin mimetics; however, a significant drawback is their unspecific mechanism of action and potentially serious side-effects related to their anticoagulant properties. Here, we have explored the use of human ScFv anti-HS antibodies (αHS as a more rational approach to target HSPG function in endothelial cells (ECs. αHS were initially selected for their recognition of HS epitopes localized preferentially to the vasculature of patient glioblastoma tumors, i.e. highly angiogenic brain tumors. Unexpectedly, we found that these αHS exhibited potent pro-angiogenic effects in primary human ECs. αHS were shown to stimulate EC differentiation, which was associated with increased EC tube formation and proliferation. Moreover, αHS supported EC survival under hypoxia and starvation, i.e. conditions typical of the tumor microenvironment. Importantly, αHS-mediated proliferation was efficiently counter-acted by heparin and was absent in HSPG-deficient mutant cells, confirming HS-specific effects. On a mechanistic level, binding of αHS to HSPGs of ECs as well as glioblastoma cells was found to trigger p38 MAPK-dependent signaling resulting in increased proliferation. We conclude that several αHS that recognize HS epitopes abundant in the tumor vasculature may elicit a pro-angiogenic response, which has implications for the development of antibody-based targeting of HSPGs in cancer.

  17. Sugar-starvation-induced changes of carbon metabolism in excised maize root tips

    International Nuclear Information System (INIS)

    Dieuaide-Noubhani, M.; Canioni, P.; Raymond, P.

    1997-01-01

    Excised maize (Zea mays L.) root tips were used to study the early metabolic effects of glucose (Glc) starvation. Root tips were prelabeled with [1-13C]Glc so that carbohydrates and metabolic intermediates were close to steady-state labeling, but lipids and proteins were scarcely labeled. They were then incubated in a sugar-deprived medium for carbon starvation. Changes in the level of soluble sugars, the respiratory quotient, and the 13C enrichment of intermediates, as measured by 13C and 1H nuclear magnetic resonance, were studied to detect changes in carbon fluxes through glycolysis and the tricarboxylic acid cycle. Labeling of glutamate carbons revealed two major changes in carbon input into the tricarboxylic acid cycle: (a) the phosphoenolpyruvate carboxylase flux stopped early after the start of Glc starvation, and (b) the contribution of glycolysis as the source of acetyl-coenzyme A for respiration decreased progressively, indicating an increasing contribution of the catabolism of protein amino acids, fatty acids, or both. The enrichment of glutamate carbons gave no evidence for proteolysis in the early steps of starvation, indicating that the catabolism of proteins was delayed compared with that of fatty acids. Labeling of carbohydrates showed that sucrose turnover continues during sugar starvation, but gave no indication for any significant flux through gluconeogenesis

  18. Resistance to starvation of first-stage juveniles of the Caribbean spiny lobster

    Directory of Open Access Journals (Sweden)

    Alí Espinosa-Magaña

    2017-01-01

    Full Text Available The non-feeding postlarva (puerulus of spiny lobsters actively swims from the open ocean to the coastal habitats where it settles and molts to the first-stage juvenile (JI. Because pueruli use much of their energy reserves swimming and preparing for the post-settlement molt, the survival of JIs presumably depends on resuming feeding as soon as possible. To test this hypothesis, the resistance to starvation of JIs of the Caribbean spiny lobster, Panulirus argus, was evaluated by measuring their point-of-no-return (PNR, minimum time of initial starvation preventing recovery after later feeding and point-of-reserve-saturation (PRS, minimum time of initial feeding allowing for food-independent development through the rest of the molting cycle in a warm and a cold season. Each experiment consisted of eight groups: a continuously fed control (FC group, a continuously starved control (SC group, and six groups subjected to differential periods of either initial starvation and subsequent feeding (PNR experiments or initial feeding and subsequent starvation (PSR experiments. No JIs molted under continuous absence of food (SC. In both PNR experiments (temperature in warm season: 29.79 ± 0.07°C, mean ± 95% CI; in cold season: 25.63 ± 0.12°C mortality increased sharply after 9 d of initial starvation and intermolt periods increased with period of initial starvation, but were longer in the cold season. The PNR50 was longer in the warm season (12.1 ± 1.2 d, mean ± 95% CI than in the cold season (9.5 ± 2.1 d. In PRS experiments (temperature in warm season: 29.54 ± 0.07 °C; in cold season: 26.20 ± 0.12 °C, JIs that molted did so near the end of the feeding period; all JIs initially fed for up to 6 d succumbed, and no JIs molted after 13 d of starvation despite having fed previously. The PRS50 did not differ between the cold (13.1 ± 0.7 d and warm seasons (12.1 ± 1.1 d. JIs of P. argus exhibit a remarkable resistance to

  19. Acute starvation ketoacidosis in pregnancy with severe hypertriglyceridemia: A case report.

    Science.gov (United States)

    Hui, Li; Shuying, Li

    2018-05-01

    Pregnant women are more prone to ketosis due to the relative insulin resistance, accelerated lipolysis and increased free fatty acids. We report a pregnant woman with hyperlipidemia, who experienced severe metabolic acidosis after a short period of starvation. Based on her clinical symptoms, exclusion diagnosis and therapeutic diagnosis, her condition was diagnosed as starvation ketoacidosis. An emergency caesarean section under general anesthesia was implemented 2 hours after her admission. The metabolic acidosis was treated with fluid resuscitation using compound sodium lactate, bicarbonate, and 5% dextrose together with insulin 6U. Both mother and baby were discharged clinically well. Starvation ketoacidosis may happen in special patient who was in pregnancy and with severe hypertriglyceridemia, after just one day fasting and vomiting.

  20. Phosphorus starvation induces membrane remodeling and recycling in Emiliania huxleyi.

    Science.gov (United States)

    Shemi, Adva; Schatz, Daniella; Fredricks, Helen F; Van Mooy, Benjamin A S; Porat, Ziv; Vardi, Assaf

    2016-08-01

    Nutrient availability is an important factor controlling phytoplankton productivity. Phytoplankton contribute c. 50% of the global photosynthesis and possess efficient acclimation mechanisms to cope with nutrient stress. We investigate the cellular response of the bloom-forming coccolithophore Emiliania huxleyi to phosphorus (P) scarcity, which is often a limiting factor in marine ecosystems. We combined mass spectrometry, fluorescence microscopy, transmission electron microscopy (TEM) and gene expression analyses in order to assess diverse cellular features in cells exposed to P limitation and recovery. Early starvation-induced substitution of phospholipids in the cells' membranes with galacto- and betaine lipids. Lipid remodeling was rapid and reversible upon P resupply. The PI3K inhibitor wortmannin reduced phospholipid substitution, suggesting a possible involvement of PI3K- signaling in this process. In addition, P limitation enhanced the formation and acidification of membrane vesicles in the cytoplasm. Intracellular vesicles may facilitate the recycling of cytoplasmic content, which is engulfed in the vesicles and delivered to the main vacuole. Long-term starvation was characterized by a profound increase in cell size and morphological alterations in cellular ultrastructure. This study provides cellular and molecular basis for future ecophysiological assessment of natural E. huxleyi populations in oligotrophic regions. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  1. A survey of the signal stability and radiation dose response of sulfates in the context of adapting optical dating for Mars

    International Nuclear Information System (INIS)

    O'Connor, V.A.; Lepper, K.; Morken, T.O.; Thorstad, D.J.; Podoll, A.; Giles, M.J.

    2011-01-01

    The Martian landscape is currently dominated by eolian processes, and eolian dunes are a direct geomorphic expression of the dynamic interaction between the atmosphere and the lithosphere of planets. The timing, frequency, and spatial extent of dune mobility directly reflects changing climatic conditions, therefore, sedimentary depositional ages are important for understanding the paleoclimatic and geomorphologic history of features and processes present on the surface of the Earth or Mars. Optical dating is an established terrestrial dosimetric dating technique that is being developed for this task on Mars. Gypsum and anhydrite are two of the most stable and abundant sulfate species found on the Earth, and they have been discovered in Martian sediments along with various magnesium sulfates and jarosite. In this study, the optical dating properties of various Ca-, Mg-, and Fe-bearing sulfates were documented to help evaluate the influence they may have on in-situ optical dating in eolian environments on Mars. Single-aliquot regenerative-dose (SAR) experimental procedures have been adapted to characterize the radiation dose response and signal stability of the Martian sulfate analogs. Jarosite was dosimetrically inert in our experiments. The radiation dose response of the Ca- and Mg-sulfates was monotonically increasing in all cases with characteristic doses ranging from ∼100 to ∼1000 Gy. Short-term signal fading also varied considerably in the Ca- and Mg-sulfates ranging from ∼0% to ∼40% per decade for these materials. These results suggest that the OSL properties of Ca- and Mg-sulfates will need to be considered when developing protocols for in-situ optical dating on Mars, but more enticingly, our results foreshadow the potential for gypsum to be developed as a geochronometer for Mars or the Earth. - Highlights: → The radiation dose response and OSL signal stability of Ca- and Mg-sulfates was highly variable. → OSL properties of Ca- and Mg-sulfates

  2. Heparan sulfate and cell division

    Directory of Open Access Journals (Sweden)

    Porcionatto M.A.

    1999-01-01

    Full Text Available Heparan sulfate is a component of vertebrate and invertebrate tissues which appears during the cytodifferentiation stage of embryonic development. Its structure varies according to the tissue and species of origin and is modified during neoplastic transformation. Several lines of experimental evidence suggest that heparan sulfate plays a role in cellular recognition, cellular adhesion and growth control. Heparan sulfate can participate in the process of cell division in two distinct ways, either as a positive or negative modulator of cellular proliferation, or as a response to a mitogenic stimulus.

  3. Starvation induces phenotypic diversification and convergent evolution in Vibrio vulnificus.

    Directory of Open Access Journals (Sweden)

    Hwajiun Chen

    Full Text Available Starvation is a common stress experienced by bacteria living in natural environments and the ability to adapt to and survive intense stress is of paramount importance for any bacterial population. A series of starvation experiments were conducted using V. vulnificus 93U204 in phosphate-buffered saline and seawater. The starved population entered the death phase during the first week and approximately 1% of cells survived. After that the population entered a long-term stationary phase, and could survive for years. Starvation-induced diversification (SID of phenotypes was observed in starved populations and phenotypic variants (PVs appeared in less than 8 days. The cell density, rather than the population size, had a major effect on the extent of SID. SID was also observed in strain YJ016, where it evolved at a faster pace. PVs appeared to emerge in a fixed order: PV with reduced motility, PV with reduced proteolytic activity, and PV with reduced hemolytic activity. All of the tested PVs had growth advantages in the stationary phase phenotypes and increased fitness compared with 93U204 cells in co-culture competition experiments, which indicates that they had adapted to starvation. We also found that SID occurred in natural seawater with a salinity of 1%-3%, so this mechanism may facilitate bacterial adaptation in natural environments.

  4. Free Amino Acids in the Blood Plasma of Pigs during Total Starvation

    Energy Technology Data Exchange (ETDEWEB)

    Cuperlovic, M.; Jovanovic, M.; Stosic, D. [Institute for the Application of Nuclear Energy in Agriculture, Veterinary Medicine and Forestry, Belgrade, Yugoslavia (Serbia)

    1968-07-01

    From the nutritional point of view it is interesting to establish whether the level of free amino acids in the blood plasma can be used as an indicator of protein anabolism and catabolism. Investigations to date have given no answer to this question. It is known that numerous exogenous and endogenous factors affect protein metabolism. These effects also vary with the level of protein intake and make the relationship between the quantitative and qualitative composition of the free amino acids pool and the total protein metabolism even more complicated. To reduce some of these factors, these investigations were done under the conditions of complete exclusion of exogenous nutrition. Piglets, aged 8-10 weeks, were subjected to total starvation in the course of 28 d. During this period, the body weight, serum protein content, plasma amino acid concentration and plasma urea concentration were followed. During the whole experimental period the body weight decreased, rapidly at the beginning and more slowly towards the end. The mean total body weight loss was 44.6 % of the first day's weight. The serum protein content increased slightly at the beginning of starvation and then, towards the end of the experiment, decreased, reaching a value that was only a little lower than the protein content determined before the onset of starvation. Changes of the quantitative composition.of the free amino acid pool did not follow the changes of the serum protein content. At the beginning of starvation, concentrations of a great number of amino acids increased in accordance with some earlier results. After long periods of starvation, however, differences between individual amino acids become more clear. Concentrations of some amino acids, e.g. lysine, increased continually during the whole period, while concentrations of most of the other amino acids remained for some time at high levels and only in the last week of starvation decreased to the values similar to those observed at the

  5. Starvation Promotes Autophagy-Associated Maturation of the Ovary in the Giant Freshwater Prawn, Macrobrachium rosenbergii

    Directory of Open Access Journals (Sweden)

    Wilairat Kankuan

    2017-05-01

    Full Text Available Limitation of food availability (starvation is known to influence the reproductive ability of animals. Autophagy is a lysosomal driven degradation process that protects the cell under metabolic stress conditions, such as during nutrient shortage. Whether, and how starvation-induced autophagy impacts on the maturation and function of reproductive organs in animals are still open questions. In this study, we have investigated the effects of starvation on histological and cellular changes that may be associated with autophagy in the ovary of the giant freshwater prawn, Macrobachium rosenbergii. To this end, the female prawns were daily fed (controls or unfed (starvation condition for up to 12 days, and the ovary tissue was analyzed at different time-points. Starvation triggered ovarian maturation, and concomitantly increased the expression of autophagy markers in vitellogenic oocytes. The immunoreactivities for autophagy markers, including Beclin1, LC3-II, and Lamp1, were enhanced in the late oocytes within the mature ovaries, especially at the vitellogenic stages. These markers co-localized with vitellin in the yolk granules within the oocytes, suggesting that autophagy induced by starvation could drive vitellin utilization, thus promoting ovarian maturation.

  6. Starvation beneficially influences the liver physiology and nutrient metabolism in Edwardsiella tarda infected red sea bream (Pagrus major).

    Science.gov (United States)

    Mohapatra, Sipra; Chakraborty, Tapas; Shimizu, Sonoko; Urasaki, Shintaro; Matsubara, Takahiro; Nagahama, Yoshitaka; Ohta, Kohei

    2015-11-01

    Dietary compromises, especially food restrictions, possess species-specific effects on the health status and infection control in several organisms, including fish. To understand the starvation-mediated physiological responses in Edwardsiella tarda infected red sea bream, especially in the liver, we performed a 20-day starvation experiment using 4 treatment (2 fed and 2 starved) groups, namely, fed-placebo, starved-placebo, fed-infected, and starved-infected, wherein bacterial exposure was done on the 11th day. In the present study, the starved groups showed reduced hepatosomatic index and drastic depletion in glycogen storage and vacuole formation. The fed-infected fish showed significant (Pred sea bream. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Effect of confinement and starvation on stress parameters in the American lobster (Homarus americanus

    Directory of Open Access Journals (Sweden)

    Edo D'Agaro

    2014-12-01

    Full Text Available The American lobster (Homarus americanus is one of the most important crustacean resources in North America. In Italy and Europe, this fishery product is available throughout the year and it has a high and increasing commercial demand. American lobsters are traditionally marketed live and stocked, without feed, in temperature controlled recirculating systems for several weeks before being sold in the market places. The current Italian legislation does not fix a maximum length of time for the crustacean confinement and specific welfare requirements. In the present research, a 4-week experiment was carried out using 42 adult H. americanus reared in 4 recirculating aquaculture tanks. After one month of confinement, mean glucose, protein and total haemocyte count levels in the hemolymph of H. americanus were stable and similar (P>0.05 to the values observed at the beginning of the experiment. Results of the proximate analysis of the abdominal muscles of H. americanus showed no significant differences in concentrations of crude protein, lipid and ash during the trial. At the end of the experiment, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analysis revealed a marked degradation of the muscle myofibrillar proteins. A number of fragments, possibly from myosin, were evident in the range between 50 and 220 kDa between time t0 and t28. Results of this study show that the main hemolymphatic variables and degradation analysis of the muscle myofibrillar proteins can be used as sensitive indicators of the crustacean stress response to confinement and starvation.

  8. A TRPV channel modulates C. elegans neurosecretion, larval starvation survival, and adult lifespan.

    Directory of Open Access Journals (Sweden)

    Brian H Lee

    2008-10-01

    Full Text Available For most organisms, food is only intermittently available; therefore, molecular mechanisms that couple sensation of nutrient availability to growth and development are critical for survival. These mechanisms, however, remain poorly defined. In the absence of nutrients, newly hatched first larval (L1 stage Caenorhabditis elegans halt development and survive in this state for several weeks. We isolated mutations in unc-31, encoding a calcium-activated regulator of neural dense-core vesicle release, which conferred enhanced starvation survival. This extended survival was reminiscent of that seen in daf-2 insulin-signaling deficient mutants and was ultimately dependent on daf-16, which encodes a FOXO transcription factor whose activity is inhibited by insulin signaling. While insulin signaling modulates metabolism, adult lifespan, and dauer formation, insulin-independent mechanisms that also regulate these processes did not promote starvation survival, indicating that regulation of starvation survival is a distinct program. Cell-specific rescue experiments identified a small subset of primary sensory neurons where unc-31 reconstitution modulated starvation survival, suggesting that these neurons mediate perception of food availability. We found that OCR-2, a transient receptor potential vanilloid (TRPV channel that localizes to the cilia of this subset of neurons, regulates peptide-hormone secretion and L1 starvation survival. Moreover, inactivation of ocr-2 caused a significant extension in adult lifespan. These findings indicate that TRPV channels, which mediate sensation of diverse noxious, thermal, osmotic, and mechanical stimuli, couple nutrient availability to larval starvation survival and adult lifespan through modulation of neural dense-core vesicle secretion.

  9. Holothurian Fucosylated Chondroitin Sulfate

    Directory of Open Access Journals (Sweden)

    Vitor H. Pomin

    2014-01-01

    Full Text Available Fucosylated chondroitin sulfate (FucCS is a structurally distinct glycosaminoglycan found in sea cucumber species. It has the same backbone composition of alternating 4-linked glucuronic acid and 3-linked N-acetyl galactosamine residues within disaccharide repeating units as regularly found in mammalian chondroitin sulfates. However, FucCS has also sulfated fucosyl branching units 3-O-linked to the acid residues. The sulfation patterns of these branches vary accordingly with holothurian species and account for different biological actions and responses. FucCSs may exhibit anticoagulant, antithrombotic, anti-inflammatory, anticancer, antiviral, and pro-angiogenic activities, besides its beneficial effects in hemodialysis, cellular growth modulation, fibrosis and hyperglycemia. Through an historical overview, this document covers most of the science regarding the holothurian FucCS. Both structural and medical properties of this unique GAG, investigated during the last 25 years, are systematically discussed herein.

  10. Sulfation of chondroitin. Specificity, degree of sulfation, and detergent effects with 4-sulfating and 6-sulfating microsomal systems

    International Nuclear Information System (INIS)

    Sugumaran, G.; Silbert, J.E.

    1988-01-01

    Microsomal preparations from chondroitin 6-sulfate-producing chick embryo epiphyseal cartilage, and from chondroitin 4-sulfate-producing mouse mastocytoma cells, were incubated with UDP-[14C]glucuronic acid and UDP-N-acetylgalactosamine to form non-sulfated proteo[14C]chondroitin. Aliquots of the incubations were then incubated with 3'-phosphoadenylylphosphosulfate (PAPS) in the presence or absence of various detergents. In the absence of detergents, there was good sulfation of this endogenous proteo[14C]chondroitin by the original microsomes from both sources. Detergents, with the exception of Triton X-100, markedly inhibited sulfation in the mast cell system but not in the chick cartilage system. These results indicate that sulfation and polymerization are closely linked on cell membranes and that in some cases this organization can be disrupted by detergents. When aliquots of the original incubation were heat inactivated, and then reincubated with new microsomes from chick cartilage and/or mouse mastocytoma cells plus PAPS, there was no significant sulfation of this exogenous proteo[14C] chondroitin with either system unless Triton X-100 was added. Sulfation of exogenous chondroitin and chondroitin hexasaccharide was compared with sulfation of endogenous and exogenous proteo[14C]chondroitin. Sulfate incorporation into hexasaccharide and chondroitin decreased as their concentrations (based on uronic acid) approached that of the proteo[14C]chondroitin. At the same time, the degree of sulfation in percent of substituted hexosamine increased. However, the degree of sulfation did not reach that of the endogenous proteo[14C]chondroitin. Hexasaccharide and chondroitin sulfation were stimulated by the presence of Triton X-100. However, in contrast to the exogenous proteo[14C]chondroitin, there was some sulfation of hexasaccharide and chondroitin in the absence of this detergent

  11. Investigation and optimization of the novel UASB-MFC integrated system for sulfate removal and bioelectricity generation using the response surface methodology (RSM).

    Science.gov (United States)

    Zhang, Baogang; Zhang, Jing; Yang, Qi; Feng, Chuanping; Zhu, Yuling; Ye, Zhengfang; Ni, Jinren

    2012-11-01

    COD/sulfate ratio and hydraulic residence time (HRT), both of which influence sulfate loadings jointly, are recognized as the most two important affecting factors for sulfate removal and bioelectricity generation in the novel up-flow anaerobic sludge blanket reactor-microbial fuel cell (UASB-MFC) integrated system. The response surface methodology (RSM) was employed for the optimization of this system and the optimum condition with COD/sulfate ratio of 2.3 and HRT of 54.3h was obtained with the target of maximizing the power output. In terms of maximizing the total sulfate removal efficiency, the obtained optimum condition was COD/sulfate ratio of 3.7 and HRT of 55.6h. Experimental results indicated the undistorted simulation and reliable optimized results. These demonstrated that RSM was effective to evaluate and optimize the UASB-MFC system for sulfate removal and energy recovery, providing a promising guide to further improvement of the system for potential applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors

    NARCIS (Netherlands)

    Villa Gomez, D.K.; Cassidy, J.; Keesman, K.J.; Sampaio, R.M.; Lens, P.N.L.

    2014-01-01

    Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4 2- ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing

  13. 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...

  14. Metabolic observations during the treatment of obese patients by periods of total starvation

    NARCIS (Netherlands)

    Riet, H.G. van; Schwarz, F.; Kinderen, P.J. der; Veeman, W.

    Ten very obese female patients were treated by periods of total starvation lasting 10 days each. In the interval between these starvation periods, a diet of 600 calories was given. Twenty-one periods were completed, 6 patients went through 3 periods each. The fasting was generally well tolerated;

  15. System-level analysis of genes and functions affecting survival during nutrient starvation in Saccharomyces cerevisiae.

    Science.gov (United States)

    Gresham, David; Boer, Viktor M; Caudy, Amy; Ziv, Naomi; Brandt, Nathan J; Storey, John D; Botstein, David

    2011-01-01

    An essential property of all cells is the ability to exit from active cell division and persist in a quiescent state. For single-celled microbes this primarily occurs in response to nutrient deprivation. We studied the genetic requirements for survival of Saccharomyces cerevisiae when starved for either of two nutrients: phosphate or leucine. We measured the survival of nearly all nonessential haploid null yeast mutants in mixed populations using a quantitative sequencing method that estimates the abundance of each mutant on the basis of frequency of unique molecular barcodes. Starvation for phosphate results in a population half-life of 337 hr whereas starvation for leucine results in a half-life of 27.7 hr. To measure survival of individual mutants in each population we developed a statistical framework that accounts for the multiple sources of experimental variation. From the identities of the genes in which mutations strongly affect survival, we identify genetic evidence for several cellular processes affecting survival during nutrient starvation, including autophagy, chromatin remodeling, mRNA processing, and cytoskeleton function. In addition, we found evidence that mitochondrial and peroxisome function is required for survival. Our experimental and analytical methods represent an efficient and quantitative approach to characterizing genetic functions and networks with unprecedented resolution and identified genotype-by-environment interactions that have important implications for interpretation of studies of aging and quiescence in yeast.

  16. Is chondroitin sulfate responsible for the biological effects attributed to the GC protein-derived Macrophage Activating Factor (GcMAF)?

    Science.gov (United States)

    Ruggiero, Marco; Reinwald, Heinz; Pacini, Stefania

    2016-09-01

    We hypothesize that a plasma glycosaminoglycan, chondroitin sulfate, may be responsible for the biological and clinical effects attributed to the Gc protein-derived Macrophage Activating Factor (GcMAF), a protein that is extracted from human blood. Thus, Gc protein binds chondroitin sulfate on the cell surface and such an interaction may occur also in blood, colostrum and milk. This interpretation would solve the inconsistencies encountered in explaining the effects of GcMAF in vitro and in vivo. According to our model, the Gc protein or the GcMAF bind to chondroitin sulfate both on the cell surface and in bodily fluids, and the resulting multimolecular complexes, under the form of oligomers trigger a transmembrane signal or, alternatively, are internalized and convey the signal directly to the nucleus thus eliciting the diverse biological effects observed for both GcMAF and chondroitin sulfate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Starvation Ketoacidosis: A Cause of Severe Anion Gap Metabolic Acidosis in Pregnancy

    Directory of Open Access Journals (Sweden)

    Nupur Sinha

    2014-01-01

    Full Text Available Pregnancy is a diabetogenic state characterized by relative insulin resistance, enhanced lipolysis, elevated free fatty acids and increased ketogenesis. In this setting, short period of starvation can precipitate ketoacidosis. This sequence of events is recognized as “accelerated starvation.” Metabolic acidosis during pregnancy may have adverse impact on fetal neural development including impaired intelligence and fetal demise. Short periods of starvation during pregnancy may present as severe anion gap metabolic acidosis (AGMA. We present a 41-year-old female in her 32nd week of pregnancy, admitted with severe AGMA with pH 7.16, anion gap 31, and bicarbonate of 5 mg/dL with normal lactate levels. She was intubated and accepted to medical intensive care unit. Urine and serum acetone were positive. Evaluation for all causes of AGMA was negative. The diagnosis of starvation ketoacidosis was established in absence of other causes of AGMA. Intravenous fluids, dextrose, thiamine, and folic acid were administered with resolution of acidosis, early extubation, and subsequent normal delivery of a healthy baby at full term. Rapid reversal of acidosis and favorable outcome are achieved with early administration of dextrose containing fluids.

  18. Degradation of protein translation machinery by amino acid starvation-induced macroautophagy

    DEFF Research Database (Denmark)

    Gretzmeier, Christine; Eiselein, Sven; Johnson, Gregory R.

    2017-01-01

    , unbiased approaches relying on quantitative mass spectrometry-based proteomics. Macroautophagy is induced by rapamycin treatment, and by amino acid and glucose starvation in differentially, metabolically labeled cells. Protein dynamics are linked to image-based models of autophagosome turnover. Depending...... on the inducing stimulus, protein as well as organelle turnover differ. Amino acid starvation-induced macroautophagy leads to selective degradation of proteins important for protein translation. Thus, protein dynamics reflect cellular conditions in the respective treatment indicating stimulus-specific pathways...

  19. Sulfate metabolism. I. Sulfate uptake and redistribution of acid rain sulfate by edible plants

    International Nuclear Information System (INIS)

    Dallam, R.D.

    1987-01-01

    Sulfur is the major component of polluted air in industrialized societies. Atmospheric sulfur is converted to sulfuric acid through a series of chemical reactions which can eventually reenter many ecosystems. When edible plants are grown in soils containing varying amounts of sulfate, the roots take up and transport inorganic sulfate to the stems and leaves. The sulfate taken up by the roots and the amount transported to the stem and leaves was found to be a function of the concentration of sulfate in the soil. Inorganic sulfate taken up by a corn plant seedling can be rapidly converted to organic sulfate by the root system. Nine days after one of a pair of pea plants was inoculated with artificial acid rain sulfate (dilute H 2 35 SO 4 ) it was found that the sulfate was translocated not only in the inoculated plant, but also to the uninoculated pea plant in the same container. Also, when the leaves of a mature potato plant were inoculated with artificial acid rain sulfate it was found that the sulfate was translocated into the edible potatoes. Fractionation of the potatoes showed that most of the sulfate was water soluble of which 30% was inorganic sulfate and 70% was in the form of organic sulfur. One third of the non-water soluble translocated acid rain sulfate was equally divided between lipid and non-lipid organic sulfur of the potato. 9 references, 2 figures, 5 tables

  20. [Effects of starvation on the consumption of energy sources and swimming performance in juvenile Gambusia affinis and Tanichthys albonubes].

    Science.gov (United States)

    Li, Jiang-tao; Lin, Xiao-tao; Zhou, Chen-hui; Zeng, Peng; Xu, Zhong-neng; Sun, Jun

    2016-01-01

    To explore the consumption of energy sources and swimming performance of juvenile Gambusia affinis and Tanichthys albonubes after starvation, contents of glycogen, lipid and protein, burst swimming speeds (Uburst), and critical swimming speeds (Ucrit) at different starvation times (0, 10, 20, 30 and 40 days) were evaluated. The results showed that, at 0 day, contents of glycogen and lipid were significantly lower in G. affinis than those in T. albonubes, whereas no significant difference in content of protein between two experimental fish was found. Swimming speeds in G. affinis were significantly lower than those in T. albonubes for all swimming performances. After different starvation scenarios, content of glycogen both in G. affinis and T. albonubes decreased significantly in power function trend with starvation time and were close to zero after starvation for 10 days, whereas the contents of lipid and protein were linearly significantly decreased. The slope of line regression equation between content of lipid and starvation time in G. affinis was significantly lower than that in T. albonubes, whereas there was a significantly higher slope of line equation between content of protein and starvation time in G. affinis. 40 days later, the consumption rate of glycogen both in G. affinis and T. albonubes were significantly higher than that of lipid, while the consumption rate of protein was the least. Consumption amounts of glycogen in all experimental fish were the least, G. affinis consumed more protein than lipid, and T. albonubes consumed more lipid than protein. Uburst and Ucrit decreased significantly linearly with starvation time for all experimental fish. Slope of linear equation between Uburst and starvation time was not significantly different between G. affinis and T. albonubes. However, the straight slope between Ucrit and starvation time was significantly lower in G. affinis than that in T. albonubes. These findings indicated that there was close

  1. Fuel starvation. Irreversible degradation mechanisms in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, Carmen M.; Silva, R.A.; Travassos, M.A.; Paiva, T.I.; Fernandes, V.R. [LNEG, National Laboratory for Energy and Geology, Lisboa (Portugal). UPCH Fuel Cells and Hydrogen Unit

    2010-07-01

    PEM fuel cell operates under very aggressive conditions in both anode and cathode. Failure modes and mechanism in PEM fuel cells include those related to thermal, chemical or mechanical issues that may constrain stability, power and lifetime. In this work, the case of fuel starvation is examined. The anode potential may rise to levels compatible with the oxidization of water. If water is not available, oxidation of the carbon support will accelerate catalyst sintering. Diagnostics methods used for in-situ and ex-situ analysis of PEM fuel cells are selected in order to better categorize irreversible changes of the cell. Electrochemical Impedance Spectroscopy (EIS) is found instrumental in the identification of fuel cell flooding conditions and membrane dehydration associated to mass transport limitations / reactant starvation and protonic conductivity decrease, respectively. Furthermore, it indicates that water electrolysis might happen at the anode. Cross sections of the membrane catalyst and gas diffusion layers examined by scanning electron microscopy indicate electrode thickness reduction as a result of reactions taking place during hydrogen starvation. Catalyst particles are found to migrate outwards and located on carbon backings. Membrane degradation in fuel cell environment is analyzed in terms of the mechanism for fluoride release which is considered an early predictor of membrane degradation. (orig.)

  2. Different Metabolomic Responses to Carbon Starvation between Light and Dark Conditions in the Purple Photosynthetic Bacterium, Rhodopseudomonas palustris.

    Science.gov (United States)

    Kanno, Nanako; Matsuura, Katsumi; Haruta, Shin

    2018-03-29

    Purple photosynthetic bacteria utilize light energy for growth. We previously demonstrated that light energy contributed to prolonging the survival of multiple purple bacteria under carbon-starved conditions. In order to clarify the effects of illumination on metabolic states under carbon-starved, non-growing conditions, we herein compared the metabolic profiles of starved cells in the light and dark using the purple bacterium, Rhodopseudomonas palustris. The metabolic profiles of starved cells in the light were markedly different from those in the dark. After starvation for 5 d in the light, cells showed increases in the amount of ATP and the NAD + /NADH ratio. Decreases in the amounts of most metabolites related to glycolysis and the TCA cycle in energy-rich starved cells suggest the active utilization of these metabolites for the modification of cellular components. Starvation in the dark induced the consumption of cellular compounds such as amino acids, indicating that the degradation of these cellular components produced ATP in order to maintain viability under energy-poor conditions. The present results suggest that intracellular energy levels alter survival strategies under carbon-starved conditions through metabolism.

  3. Regulation of autophagy by sphingosine kinase 1 and its role in cell survival during nutrient starvation.

    Science.gov (United States)

    Lavieu, Grégory; Scarlatti, Francesca; Sala, Giusy; Carpentier, Stéphane; Levade, Thierry; Ghidoni, Riccardo; Botti, Joëlle; Codogno, Patrice

    2006-03-31

    The sphingolipid ceramide induces macroautophagy (here called autophagy) and cell death with autophagic features in cancer cells. Here we show that overexpression of sphingosine kinase 1 (SK1), an enzyme responsible for the production of sphingosine 1-phosphate (S1P), in MCF-7 cells stimulates autophagy by increasing the formation of LC3-positive autophagosomes and the rate of proteolysis sensitive to the autophagy inhibitor 3-methyladenine. Autophagy was blocked in the presence of dimethylsphingosine, an inhibitor of SK activity, and in cells expressing a catalytically inactive form of SK1. In SK1(wt)-overexpressing cells, however, autophagy was not sensitive to fumonisin B1, an inhibitor of ceramide synthase. In contrast to ceramide-induced autophagy, SK1(S1P)-induced autophagy is characterized by (i) the inhibition of mammalian target of rapamycin signaling independently of the Akt/protein kinase B signaling arm and (ii) the lack of robust accumulation of the autophagy protein Beclin 1. In addition, nutrient starvation induced both the stimulation of autophagy and SK activity. Knocking down the expression of the autophagy protein Atg7 or that of SK1 by siRNA abolished starvation-induced autophagy and increased cell death with apoptotic hallmarks. In conclusion, these results show that SK1(S1P)-induced autophagy protects cells from death with apoptotic features during nutrient starvation.

  4. [Research of Embryonic Mortality Stages of Drosophila melanogaster Depending on Age and Starvation of an Imago].

    Science.gov (United States)

    Kostenko, V V; Kolot, N V; Vorobyova, L I

    2015-01-01

    Influence of age of parents and duration of starvation on egg production and demonstration of embryonic mortality at different stages of egg development has been studied. It is shown that, with increasing age of organisms, the overall egg production reduces and the percentage of embryonic mortality increases at 0-5.5 and 5.5-17 h of development. An increase in the duration of starvation also promotes a reduction in egg production in 3- and 10-day-old adult D. melanogaster compared with short-term starvation. A statistically significant effect of factors, such as the allelic state of the white locus, the genetic background, the age of the parents, and the duration of starvation, on all studied parameters was established.

  5. Ethylene signalling is involved in regulation of phosphate starvation-induced gene expression and production of acid phosphatases and anthocyanin in Arabidopsis

    KAUST Repository

    Lei, Mingguang; Zhu, Chuanmei; Liu, Yidan; Karthikeyan, Athikkattuvalasu S.; Bressan, Ray Anthony; Raghothama, Kashchandra G.; Liu, Dong

    2010-01-01

    With the exception of root hair development, the role of the phytohormone ethylene is not clear in other aspects of plant responses to inorganic phosphate (Pi) starvation. The induction of AtPT2 was used as a marker to find novel signalling

  6. Phosphoproteome of the cyanobacterium Synechocystis sp. PCC 6803 and its dynamics during nitrogen starvation.

    Directory of Open Access Journals (Sweden)

    Philipp eSpät

    2015-03-01

    Full Text Available Cyanobacteria have shaped the earth’s biosphere as the first oxygenic photoautotrophs and still play an important role in many ecosystems. The ability to adapt to changing environmental conditions is an essential characteristic in order to ensure survival. To this end, numerous studies have shown that bacteria use protein post-translational modifications such as Ser/Thr/Tyr phosphorylation in cell signalling, adaptation and regulation. Nevertheless, our knowledge of cyanobacterial phosphoproteomes and their dynamic response to environmental stimuli is relatively limited. In this study, we applied gel-free methods and high accuracy mass spectrometry towards the unbiased detection of Ser/Thr/Tyr phosphorylation events in the model cyanobacterium Synechocystis sp. PCC 6803. We could identify over 300 phosphorylation events in cultures grown on nitrate as exclusive nitrogen source. Chemical dimethylation labelling was applied to investigate proteome and phosphoproteome dynamics during nitrogen starvation. Our dataset describes the most comprehensive (phosphoproteome of Synechocystis to date, identifying 2,382 proteins and 183 phosphorylation events and quantifying 2,111 proteins and 148 phosphorylation events during nitrogen starvation. Global protein phosphorylation levels were increased in response to nitrogen depletion after 24 hours. Among the proteins with increased phosphorylation, the PII signalling protein showed the highest fold-change, serving as positive control. Other proteins with increased phosphorylation levels comprised functions in photosynthesis and in carbon and nitrogen metabolism. This study reveals dynamics of Synechocystis phosphoproteome in response to environmental stimuli and suggests an important role of protein Ser/Thr/Tyr phosphorylation in fundamental mechanisms of homeostatic control in cyanobacteria.

  7. Developmental and age-specific effects of selection on divergent virgin life span on fat content and starvation resistance in Drosophila melanogaster

    NARCIS (Netherlands)

    Vermeulen, Cornelis; Van de Zande, Louis; Bijlsma, R.

    Investigations into the genetic basis of longevity variation have shown life span to be positively correlated with starvation resistance and negatively with female fecundity, both of which rely on lipid content. To assess the firmness of this relation, we assayed correlated responses in age-specific

  8. The Challenge of Appropriate Identification and Treatment of Starvation, Sarcopenia, and Cachexia: A Survey of Australian Dietitians

    Directory of Open Access Journals (Sweden)

    Alison Yaxley

    2011-01-01

    Full Text Available Malnutrition is an umbrella term that includes starvation, sarcopenia, and cachexia; however, differentiating between these terms is infrequent in clinical practice. Given that the effectiveness of treatment depends on the aetiology of unintentional weight loss, it is important that clinicians are aware of the defining characteristics. The aim of this study was to determine whether Australian dietitians understand and use the terms starvation, sarcopenia, and cachexia and provide targeted treatment strategies accordingly. Members of the Dietitians Association of Australia were surveyed to gain information on practices and attitudes to diagnosis and treatment of adult malnutrition. In addition, three case studies were provided to examine understanding of starvation, sarcopenia, and cachexia. 221 dietitians accessed the survey. 81 respondents (43% indicated the use of at least one alternate term (starvation, sarcopenia, and/or cachexia. Muscle wasting was the most commonly used diagnostic criterion. High-energy high-protein diet was the most common therapy prescribed. Correct diagnoses for case studies were recorded by 6% of respondents for starvation, 46% for sarcopenia, and 21% for cachexia. There is a need for increased awareness of the existence of starvation, sarcopenia, and cachexia amongst Australian dietitians and research into appropriate methods of identification and treatment for each condition.

  9. Unsatisfactory knowledge and use of terminology regarding malnutrition, starvation, cachexia and sarcopenia among dietitians.

    Science.gov (United States)

    Ter Beek, Lies; Vanhauwaert, Erika; Slinde, Frode; Orrevall, Ylva; Henriksen, Christine; Johansson, Madelene; Vereecken, Carine; Rothenberg, Elisabet; Jager-Wittenaar, Harriët

    2016-12-01

    Clinical signs of malnutrition, starvation, cachexia and sarcopenia overlap, as they all imply muscle wasting to a various extent. However, the underlying mechanisms differ fundamentally and therefore distinction between these phenomena has therapeutic and prognostic implications. We aimed to determine whether dietitians in selected European countries have 'sufficient knowledge' regarding malnutrition, starvation, cachexia and sarcopenia, and use these terms in their daily clinical work. An anonymous online survey was performed among dietitians in Belgium, the Netherlands, Norway and Sweden. 'Sufficient knowledge' was defined as having mentioned at least two of the three common domains of malnutrition according to ESPEN definition of malnutrition (2011): 'nutritional balance', 'body composition' and 'functionality and clinical outcome', and a correct answer to three cases on starvation, cachexia and sarcopenia. Chi-square test was used to analyse differences in experience, work place and number of malnourished patients treated between dietitians with 'sufficient knowledge' vs. 'less sufficient knowledge'. 712/7186 responded to the questionnaire, of which data of 369 dietitians were included in the analysis (5%). The term 'malnutrition' is being used in clinical practice by 88% of the respondents. Starvation, cachexia and sarcopenia is being used by 3%, 30% and 12% respectively. The cases on starvation, cachexia and sarcopenia were correctly identified by 58%, 43% and 74% respectively. 13% of the respondents had 'sufficient knowledge'. 31% of the respondents identified all cases correctly. The proportion of respondents with 'sufficient knowledge' was significantly higher in those working in a hospital or in municipality (16%, P four European countries show that the percentage of dietitians with 'sufficient knowledge' regarding malnutrition, starvation, cachexia and sarcopenia is unsatisfactory (13%). The terms starvation, cachexia and sarcopenia are not often used

  10. Global expression pattern comparison between low phosphorus insensitive 4 and WT Arabidopsis reveals an important role of reactive oxygen species and jasmonic acid in the root tip response to phosphate starvation

    OpenAIRE

    Chacón-López, Alejandra; Ibarra-Laclette, Enrique; Sánchez-Calderón, Lenin; Gutiérrez-Alanís, Dolores; Herrera-Estrella, Luis

    2011-01-01

    Plants are exposed to several biotic and abiotic stresses. A common environmental stress that plants have to face both in natural and agricultural ecosystems that impacts both its growth and development is low phosphate (Pi) availability. There has been an important progress in the knowledge of the molecular mechanisms by which plants cope with Pi deficiency. However, the mechanisms that mediate alterations in the architecture of the Arabidopsis root system responses to Pi starvation are stil...

  11. Severe protein-calorie malnutrition in two brothers due to abuse by starvation

    Directory of Open Access Journals (Sweden)

    Marcela Montenegro Braga Barroso

    Full Text Available Abstract Objective: To describe the case of two siblings with severe protein-calorie malnutrition due to abuse by starvation. Cases description: The two patients were simultaneously referred to the Hospital Municipal, where they were admitted to the Pediatric Gastroenterology clinic of a university hospital for diagnostic investigation of the cause of severe malnutrition and screening tests for Celiac Disease, Cystic Fibrosis and Environmental enteropathy among others. The exams were all normal, and after detailed research on the interactions of this family, we reached the conclusion that the malnutrition was due to abuse by starvation. The children spent approximately two months in the hospital, receiving a high-protein and high-calorie diet, with significant nutritional recovery. Comments: Abuse by starvation, although rare, should always be considered of as one of the causes of child malnutrition and pediatrician should be aware of the child's development, as well as the family interactions, to prevent more severe nutritional and emotional consequences in the future.

  12. Severe protein-calorie malnutrition in two brothers due to abuse by starvation.

    Science.gov (United States)

    Barroso, Marcela Montenegro Braga; Salvador, Luiza Martins; Fagundes Neto, Ulysses

    2016-12-01

    To describe the case of two siblings with severe protein-calorie malnutrition due to abuse by starvation. The two patients were simultaneously referred from the Municipal Hospital, where they were admitted to the Pediatric Gastroenterology clinic of a university hospital for diagnostic investigation of the cause of severe malnutrition and screening tests for Celiac Disease, Cystic Fibrosis and Environmental enteropathy among others. The exams were all normal, and after detailed research on the interactions of this family, we reached the conclusion that the malnutrition was due to abuse by starvation. The children spent approximately two months in the hospital, receiving a high-protein and high-calorie diet, with significant nutritional recovery. Abuse by starvation, although rare, should always be considered of as one of the causes of child malnutrition and pediatrician should be aware of the child's development, as well as the family interactions, to prevent more severe nutritional and emotional consequences in the future. Copyright © 2016. Publicado por Elsevier Editora Ltda.

  13. Effect of Thymine Starvation on Messenger Ribonucleic Acid Synthesis in Escherichia coli

    Science.gov (United States)

    Luzzati, Denise

    1966-01-01

    Luzzati, Denise (Institut de Biologie Physico-Chimique, Paris, France). Effect of thymine starvation on messenger ribonucleic acid synthesis in Escherichia coli. J. Bacteriol. 92:1435–1446. 1966.—During the course of thymine starvation, the rate of synthesis of messenger ribonucleic acid (mRNA, the rapidly labeled fraction of the RNA which decays in the presence of dinitrophenol or which hybridizes with deoxyribonucleic acid) decreases exponentially, in parallel with the viability of the thymine-starved bacteria. The ability of cell-free extracts of starved bacteria to incorporate ribonucleoside triphosphates into RNA was determined; it was found to be inferior to that of extracts from control cells. The analysis of the properties of cell-free extracts of starved cells shows that their decreased RNA polymerase activity is the consequence of a modification of their deoxyribonucleic acid, the ability of which to serve as a template for RNA polymerase decreases during starvation. PMID:5332402

  14. Expression of N-Acetylgalactosamine 4-Sulfate 6-O-Sulfotransferase Involved in Chondroitin Sulfate Synthesis Is Responsible for Pulmonary Metastasis

    Directory of Open Access Journals (Sweden)

    Shuji Mizumoto

    2013-01-01

    Full Text Available Chondroitin sulfate (CS containing E-disaccharide units, glucuronic acid-N-acetylgalactosamine(4, 6-O-disulfate, at surfaces of tumor cells plays a key role in tumor metastasis. However, the molecular mechanism of the metastasis involving the CS chain-containing E-units is not fully understood. In this study, to clarify the role of E-units in the metastasis and to search for potential molecular targets for anticancer drugs, the isolation and characterization of Lewis lung carcinoma (LLC cells stably downregulated by the knockdown for the gene encoding N-acetylgalactosamine 4-O-sulfate 6-O-sulfotransferase (GalNAc4S-6ST, which is responsible for the formation of E-units in CS chains, were performed. Knockdown of GalNAc4S-6ST in LLC cells resulted in a reduction in the proportion of E-units, in adhesiveness to extracellular matrix adhesion molecules and in proliferation in vitro. Furthermore, the stable downregulation of GalNAc4S-6ST expression in LLC cells markedly inhibited the colonization of the lungs by inoculated LLC cells and invasive capacity of LLC cells. These results provide clear evidence that CS chain-containing E-units and/or GalNAc4S-6ST play a crucial role in pulmonary metastasis at least through the increased adhesion and the invasive capacity of LLC cells and also provides insights into future drug targets for anticancer treatment.

  15. Differential impact of amino acids on OXPHOS system activity following carbohydrate starvation in Arabidopsis cell suspensions.

    Science.gov (United States)

    Cavalcanti, João Henrique F; Quinhones, Carla G S; Schertl, Peter; Brito, Danielle S; Eubel, Holger; Hildebrandt, Tatjana; Nunes-Nesi, Adriano; Braun, Hans-Peter; Araújo, Wagner L

    2017-12-01

    Plant respiration mostly depends on the activity of glycolysis and the oxidation of organic acids in the tricarboxylic acid cycle to synthesize ATP. However, during stress situations plant cells also use amino acids as alternative substrates to donate electrons through the electron-transfer flavoprotein (ETF)/ETF:ubiquinone oxidoreductase (ETF/ETFQO) complex to the mitochondrial electron transport chain (mETC). Given this, we investigated changes of the oxidative phosphorylation (OXPHOS) system in Arabidopsis thaliana cell culture under carbohydrate starvation supplied with a range of amino acids. Induction of isovaleryl-CoA dehydrogenase (IVDH) activity was observed under carbohydrate starvation which was associated with increased amounts of IVDH protein detected by immunoblotting. Furthermore, activities of the protein complexes of the mETC were reduced under carbohydrate starvation. We also observed that OXPHOS system activity behavior is differently affected by different amino acids and that proteins associated with amino acids catabolism are upregulated in cells following carbohydrate starvation. Collectively, our results support the contention that ETF/ETFQO is an essential pathway to donate electrons to the mETC and that amino acids are alternative substrates to maintain respiration under carbohydrate starvation. © 2017 Scandinavian Plant Physiology Society.

  16. Identification of genes associated with resilience/vulnerability to sleep deprivation and starvation in Drosophila.

    Science.gov (United States)

    Thimgan, Matthew S; Seugnet, Laurent; Turk, John; Shaw, Paul J

    2015-05-01

    Flies mutant for the canonical clock protein cycle (cyc(01)) exhibit a sleep rebound that is ∼10 times larger than wild-type flies and die after only 10 h of sleep deprivation. Surprisingly, when starved, cyc(01) mutants can remain awake for 28 h without demonstrating negative outcomes. Thus, we hypothesized that identifying transcripts that are differentially regulated between waking induced by sleep deprivation and waking induced by starvation would identify genes that underlie the deleterious effects of sleep deprivation and/or protect flies from the negative consequences of waking. We used partial complementary DNA microarrays to identify transcripts that are differentially expressed between cyc(01) mutants that had been sleep deprived or starved for 7 h. We then used genetics to determine whether disrupting genes involved in lipid metabolism would exhibit alterations in their response to sleep deprivation. Laboratory. Drosophila melanogaster. Sleep deprivation and starvation. We identified 84 genes with transcript levels that were differentially modulated by 7 h of sleep deprivation and starvation in cyc(01) mutants and were confirmed in independent samples using quantitative polymerase chain reaction. Several of these genes were predicted to be lipid metabolism genes, including bubblegum, cueball, and CG4500, which based on our data we have renamed heimdall (hll). Using lipidomics we confirmed that knockdown of hll using RNA interference significantly decreased lipid stores. Importantly, genetically modifying bubblegum, cueball, or hll resulted in sleep rebound alterations following sleep deprivation compared to genetic background controls. We have identified a set of genes that may confer resilience/vulnerability to sleep deprivation and demonstrate that genes involved in lipid metabolism modulate sleep homeostasis. © 2015 Associated Professional Sleep Societies, LLC.

  17. Gluconeogenesis during starvation and refeeding phase is affected by previous dietary carbohydrates levels and a glucose stimuli during early life in Siberian sturgeon (Acipenser baerii

    Directory of Open Access Journals (Sweden)

    Xiaofang Liang

    2017-09-01

    Full Text Available Gluconeogenesis responses was assessed during a short starvation period and subsequent refeeding in Siberian sturgeon (Acipenser baerii previously fed different dietary carbohydrates levels and experienced to a glucose stimuli during early life. The sturgeon larvae were previously fed either a high glucose diet (G or a low glucose diet (F from the first feeding to yolk absorption (8 to 12 d post-hatching [dph]. Each group of fish was sub-divided into 2 treatments at 13 dph and was fed either a high-carbohydrate diet (H or a low carbohydrate diet (L until 20 wk. In the current study, the fish in 4 groups (GL, FL, GH and FH were experienced to starvation for 21 d following by re-feeding of their corresponding diets for 21 d. Fish were sampled at postprandial 6 and 24 h before starvation (P6h and P24h, starvation 7, 14 and 21 d (S7, S14 and S21 and 1, 7, 14 and 21 d during refeeding (R1, R7, R14 and R21. Plasma samples during refeeding were taken at P6h at each time point. Glycaemia levels, liver and muscle glycogen contents, activities and mRNA levels of hepatic gluconeogenic enzymes were examined. We found that both dietary carbohydrate levels and early glucose stimuli significantly affected the metabolic responses to starvation and refeeding in Siberian sturgeon (P < 0.05. During prolonged starvation, Siberian sturgeon firstly mobilized the liver glycogen and then improved gluconeogenesis when the dietary carbohydrates were abundant, whereas preserved the liver glycogen stores at a stable level and more effectively promoted gluconeogenesis when the dietary carbohydrates are absent to maintain glucose homoeostasis. During refeeding, as most teleostean, Siberian sturgeon failed controlling the activities and mRNA levels of phosphoenolpyruvate carboxykinase cytosolic forms (PEPCK-C, fructose-1,6-bisphosphatase (FBPase, but particularly controlled phosphoenolpyruvate carboxykinase mitochondrial forms (PEPCK-M activities and mRNA expression

  18. Starvation reveals the cause of infection-induced castration and gigantism.

    Science.gov (United States)

    Cressler, Clayton E; Nelson, William A; Day, Troy; McCauley, Edward

    2014-10-07

    Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna-Pasteuria ramosa host-parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems.

  19. Starvation reveals the cause of infection-induced castration and gigantism

    Science.gov (United States)

    Cressler, Clayton E.; Nelson, William A.; Day, Troy; McCauley, Edward

    2014-01-01

    Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna–Pasteuria ramosa host–parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems. PMID:25143034

  20. Sulfate Transporters in Dissimilatory Sulfate Reducing Microorganisms: A Comparative Genomics Analysis

    Directory of Open Access Journals (Sweden)

    Angeliki Marietou

    2018-03-01

    Full Text Available The first step in the sulfate reduction pathway is the transport of sulfate across the cell membrane. This uptake has a major effect on sulfate reduction rates. Much of the information available on sulfate transport was obtained by studies on assimilatory sulfate reduction, where sulfate transporters were identified among several types of protein families. Despite our growing knowledge on the physiology of dissimilatory sulfate-reducing microorganisms (SRM there are no studies identifying the proteins involved in sulfate uptake in members of this ecologically important group of anaerobes. We surveyed the complete genomes of 44 sulfate-reducing bacteria and archaea across six phyla and identified putative sulfate transporter encoding genes from four out of the five surveyed protein families based on homology. We did not find evidence that ABC-type transporters (SulT are involved in the uptake of sulfate in SRM. We speculate that members of the CysP sulfate transporters could play a key role in the uptake of sulfate in thermophilic SRM. Putative CysZ-type sulfate transporters were present in all genomes examined suggesting that this overlooked group of sulfate transporters might play a role in sulfate transport in dissimilatory sulfate reducers alongside SulP. Our in silico analysis highlights several targets for further molecular studies in order to understand this key step in the metabolism of SRMs.

  1. daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival

    OpenAIRE

    Hibshman, Jonathan D; Doan, Alexander E; Moore, Brad T; Kaplan, Rebecca EW; Hung, Anthony; Webster, Amy K; Bhatt, Dhaval P; Chitrakar, Rojin; Hirschey, Matthew D; Baugh, L Ryan

    2017-01-01

    eLife digest Most animals rarely have access to a constant supply of food, and so have evolved ways to cope with times of plenty and times of shortage. Insulin is a hormone that travels throughout the body to signal when an animal is well fed. Insulin signaling inhibits the activity of a protein called FoxO, which otherwise switches on and off hundreds of genes to control the starvation response. The roundworm, Caenorhabditis elegans, has been well studied in the laboratory, and often has to ...

  2. Participation of 3-O-sulfated heparan sulfates in the protection of macrophages by herpes simplex virus-1 glycoprotein D and cyclophilin B against apoptosis.

    Science.gov (United States)

    Delos, Maxime; Hellec, Charles; Foulquier, François; Carpentier, Mathieu; Allain, Fabrice; Denys, Agnès

    2017-02-01

    Heparan sulfates (HS) are involved in numerous biological processes, which rely on their ability to interact with a large panel of proteins. Although the reaction of 3-O-sulfation can be catalysed by the largest family of HS sulfotransferases, very few mechanisms have been associated with this modification and to date, only glycoprotein D (gD) of herpes simplex virus-1 (HSV-1 gD) and cyclophilin B (CyPB) have been well-described as ligands for 3- O -sulfated HS. Here, we hypothesized that both ligands could induce the same responses via a mechanism dependent on 3- O -sulfated HS. First, we checked that HSV-1 gD was as efficient as CyPB to induce the activation of the same signalling events in primary macrophages. We then demonstrated that both ligands efficiently reduced staurosporin-induced apoptosis and modulated the expression of apoptotic genes. In addition to 3- O -sulfated HS, HSV-1 gD was reported to interact with other receptors, including herpes virus entry mediator (HVEM), nectin-1 and -2. Thus, we decided to identify the contribution of each binding site in the responses triggered by HSV-1 gD and CyPB. We found that knock-down of 3- O -sulfotransferase 2, which is the main 3- O -sulfated HS-generating enzyme in macrophages, strongly reduced the responses induced by both ligands. Moreover, silencing the expression of HVEM rendered macrophages unresponsive to either HSV-1 gD and CyPB, thus indicating that both proteins induced the same responses by interacting with a complex formed by 3- O -sulfated HS and HVEM. Collectively, our results suggest that HSV-1 might hijack the binding sites for CyPB in order to protect macrophages against apoptosis for efficient infection.

  3. Enhanced sulfate reduction with acidogenic sulfate-reducing bacteria

    International Nuclear Information System (INIS)

    Wang Aijie; Ren Nanqi; Wang Xu; Lee Duujong

    2008-01-01

    Sulfate reduction in a continuous flow, acidogenic reactor using molasses wastewater as the carbon source was studied at varying chemical oxygen demand/sulfate (COD/SO 4 2- ) ratios. At a critical COD/SO 4 2- ratio of 2.7, neither COD nor sulfate were in excess for extra production of ethanol or acetate in the reactor. An acetic-type microbial metabolism was established with sulfate-reducing bacteria (SRB) significantly consuming hydrogen and volatile fatty acids produced by acidogenic bacteria and hydrogen producing acetogens in degrading COD, thereby yielding sulfate removal rate >94.6%. A low critical COD/SO 4 2- ratio of 1.6 was also observed with the enriched ASRB population in reactor which overcomes the barrier to the treatment capability of sulfate-laden wastewater treatment with limited COD supply

  4. Compensatory growth response of rainbow trout Oncorhynchus mykiss Walbaum following short starvation periods

    Science.gov (United States)

    Azodi, Maryam; Ebrahimi, Eisa; Farhadian, Omidvar; Mahboobi-Soofiani, Nasrollah; Morshedi, Vahid

    2015-07-01

    This sixty-day study was performed to determine the effects of short-term starvation and re-feeding cycles on growth, feeding performances and body composition of rainbow trout ( Oncorhynchus mykiss). Three hundred trout fingerlings with an average initial weight of 17.5±0.06 g were randomly distributed in 15 circular fiberglass tanks. The fish were exposed to 5 different feeding regimes; control: continuously fed twice daily to apparent satiation; T1: starved for 1 day and re-fed for 2 days; T2: starved for 1 day and re-fed for 4 days; T3: starved for 3 days and re-fed for 12 days; T4: starved for 4 days and re-fed for 16 days. At the end of the experiment, growth performance, feed utilization, whole body ash and moisture contents were not significantly ( P>0.05) different among the treatments. However, whole body protein content in T3 was significantly higher than other treatments ( Ptrout culture.

  5. Reduced sulfation of chondroitin sulfate but not heparan sulfate in kidneys of diabetic db/db mice.

    Science.gov (United States)

    Reine, Trine M; Grøndahl, Frøy; Jenssen, Trond G; Hadler-Olsen, Elin; Prydz, Kristian; Kolset, Svein O

    2013-08-01

    Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes.

  6. Starvation and refeeding in rats: effect on some parameters of energy metabolism and electrolytes and changes of hepatic tissue

    Directory of Open Access Journals (Sweden)

    Fatemeh Namazi

    Full Text Available Abstract: Regarding the importance of starvation and refeeding and the occurrence of refeeding syndrome in various conditions, the present study was conducted to investigate the effects of refeeding on some parameters of energy metabolism and electrolytes and changes of hepatic tissue in male Wistar rats. Fifty-seven rats were divided into six groups, having 6 to 11 rats. Food was provided ad-libitum until three months and then the first group was considered without starvation (day 0. Other rats were fasted for two weeks. Group 2 was applied to a group immediately after starvation (day 14. Groups 3 to 6 were refed in days 16 till 22, respectively. At the end of each period, blood and tissue samples were taken and histopathological and serum analysis, including serum electrolytes (calcium, phosphorus, sodium, potassium, the energy parameters (glucose, insulin, cortisol and the liver enzymes (ALT, AST, ALP were determined. Insulin decreased by starvation and then showed an increasing trend compared to starvation period, which the highest amount of this parameter was observed eight days post-refeeding. Serum glucose level showed the opposite pattern of insulin. Histopathological examination of the tissue sections revealed clear vacuoles after starvation and refeeding, in which the severity of lesions gradually decreased during refeeding. The cortisol level decreased by starvation and then increased during refeeding. Also, potassium and phosphorus concentrations declined by refeeding and the serum sodium and potassium levels were changed in the relatively opposite manner. The calcium level decreased by starvation and then increased during refeeding. These results could help recognize and remedy the refeeding syndrome.

  7. Semi-synthesis of chondroitin sulfate-E from chondroitin sulfate-A

    OpenAIRE

    Cai, Chao; Solakyildirim, Kemal; Yang, Bo; Beaudet, Julie M.; Weyer, Amanda; Linhardt, Robert J.; Zhang, Fuming

    2012-01-01

    Chondroitin sulfate-E (chondroitin-4, 6-disulfate) was prepared from chondroitin sulfate-A (chondroitin-4 - sulfate) by regioselective sulfonation, performed using trimethylamine sulfur trioxide in formamide under argon. The structure of semi-synthetic chondroitin sulfate-E was analyzed by PAGE, 1H NMR, 13C NMR, 2D NMR and disaccharide analysis and compared with natural chondroitin sulfate-E. Both semi-synthetic and natural chondroitin sulfate-E were each biotinylated and immobilized on BIAco...

  8. Genetic parameters of the piglet mortality traits stillborn, weak at birth, starvation, crushing, and miscellaneous in crossbred pigs

    DEFF Research Database (Denmark)

    Strange, T.; Ask, B.; Nielsen, B.

    2013-01-01

    This study aimed to estimate genetic parameters for the mortality causes stillborn, weak at birth, starvation, crushing, and miscellaneous in crossbred piglets produced by crossbred dams. Data were collected in a single Danish commercial herd from October 2006 to July 2008 and consisted of 34......,194 piglets (2,152 litters), which originated from 195 Danish Duroc sires and 955 crossbreds between Danish Landrace and Danish Yorkshire dams. Of the 34,194 piglets born, 11.5% were stillborn, 4.2% were crushed by the sow, 2.7% died due to starvation, 2.3% were weak at birth, and 2.2% died of miscellaneous...... traits based on the sire component ranged from -0.05 between stillborn and starvation to 0.35 between stillborn and weak at birth whereas genetic correlations based on the dam component ranged from -0.11 between weak at birth and starvation to 0.76 between crushing and starvation. There seemed...

  9. Combined effects of starvation and butyrate on autophagy-dependent gingival epithelial cell death.

    Science.gov (United States)

    Evans, M; Murofushi, T; Tsuda, H; Mikami, Y; Zhao, N; Ochiai, K; Kurita-Ochiai, T; Yamamoto, M; Otsuka, K; Suzuki, N

    2017-06-01

    Bacteria in the dental biofilm surrounding marginal gingival grooves cause periodontal diseases. Numerous bacteria within the biofilm consume nutrients from the gingival crevicular fluid. Furthermore, some gram-negative bacteria in mature dental biofilms produce butyrate. Thus, gingival epithelial cells in close proximity to mature dental biofilms are at risk of both starvation and exposure to butyrate. In the present study, we determined the combined effects of starvation and butyrate exposure on gingival epithelial cell death and the underlying mechanisms. The Ca9-22 cell line was used as an in vitro counterpart of gingival epithelial cells. Cell death was measured as the amount of total DNA in the dead cells using SYTOX Green dye, which penetrates through membranes of dead cells and emits fluorescence when it intercalates into double-stranded DNA. AMP-activated protein kinase (AMPK) activity, the amount of autophagy, and acetylation of histone H3 were determined using western blot. Gene expression levels of microtubule-associated protein 1 light chain 3b (lc3b) were determined using quantitative reverse transcription-polymerase chain reaction. Butyrate-induced cell death occurred in a dose-dependent manner whether cells were starved or fed. However, the induction of cell death was two to four times higher when cells were placed under starvation conditions compared to when they were fed. Moreover, both starvation and butyrate exposure induced AMPK activity and autophagy. While AMPK inactivation resulted in decreased autophagy and butyrate-induced cell death under conditions of starvation, AMPK activation resulted in butyrate-induced cell death when cells were fed. Combined with the results of our previous report, which demonstrated butyrate-induced autophagy-dependent cell death, the results of this study suggest that the combination of starvation and butyrate exposure activates AMPK inducing autophagy and subsequent cell death. Notably, this combination markedly

  10. Biochemical evaluation of aestivation and starvation in two snail ...

    African Journals Online (AJOL)

    hope&shola

    2010-11-08

    Nov 8, 2010 ... food uptake ceases, water loss occurs and the snails are not able to rid .... Fasting glucose decreased in both aestivating and starved B. rohlfsi snails ... significant muscle wastage during aestivation and starvation. It has been ...

  11. The impact of food type, temperature and starvation on larval development of Balanus amphitrite Darwin (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C.

    The impact of diatom food species (Chaetoceros calcitrans and Skeletonema costatum), temperature and starvation on the larval development of Balanus amphitrite was evaluated. Starvation threshold levels for different ages of larvae (0- to 5-day...

  12. Self-starvation in context: towards a culturally sensitive understanding of anorexia nervosa.

    Science.gov (United States)

    Lee, S

    1995-07-01

    Extreme forms of self-starvation can be traced across time and place, and may be construed using a variety of explanatory models. Curiously, the prevailing biomedical definition of anorexia nervosa has assigned primacy to the exclusive use of 'fat phobia' by the affected subjects to justify their diminished food intake. This paper assembles evidence to show that this culturally constructed version of fat phobic anorexia nervosa has neglected the full metaphorical significance of self-starvation and, when applied in a cross-cultural context, may constitute a category fallacy. By delegitimizing other rationales for non-eating and thereby barring subjective expressions, this regnant interpretive strategy may obscure clinicians' understanding of patients' lived experience, and even jeopardize their treatment. Nonetheless, it is a relatively simple task to attune the extant diagnostic criteria to a polythetic approach which will avert cultural parochialism in psychiatric theory and practice. As a corollary of the archival and ethnocultural study of extreme self-starvation, there is, contrary to epistemological assumptions embedded in the biomedical culture of contemporary psychiatry, no 'core psychopathology' of anorexia nervosa.

  13. Acidity-Reactivity Relationships in Catalytic Esterification over Ammonium Sulfate-Derived Sulfated Zirconia

    Directory of Open Access Journals (Sweden)

    Abdallah I. M. Rabee

    2017-07-01

    Full Text Available New insight was gained into the acidity-reactivity relationships of sulfated zirconia (SZ catalysts prepared via (NH42SO4 impregnation of Zr(OH4 for propanoic acid esterification with methanol. A family of systematically related SZs was characterized by bulk and surface analyses including XRD, XPS, TGA-MS, N2 porosimetry, temperature-programmed propylamine decomposition, and FTIR of adsorbed pyridine, as well as methylbutynol (MBOH as a reactive probe molecule. Increasing surface sulfation induces a transition from amphoteric character for the parent zirconia and low S loadings <1.7 wt %, evidenced by MBOH conversion to 3-hydroxy-3-methyl-2-butanone, methylbutyne and acetone, with higher S loadings resulting in strong Brønsted-Lewis acid pairs upon completion of the sulfate monolayer, which favored MBOH conversion to prenal. Catalytic activity for propanoic acid esterification directly correlated with acid strength determined from propylamine decomposition, coincident with the formation of Brønsted-Lewis acid pairs identified by MBOH reactive titration. Monodispersed bisulfate species are likely responsible for superacidity at intermediate sulfur loadings.

  14. Phospho-Rasputin Stabilization by Sec16 Is Required for Stress Granule Formation upon Amino Acid Starvation

    Directory of Open Access Journals (Sweden)

    Angelica Aguilera-Gomez

    2017-07-01

    Full Text Available Most cellular stresses induce protein translation inhibition and stress granule formation. Here, using Drosophila S2 cells, we investigate the role of G3BP/Rasputin in this process. In contrast to arsenite treatment, where dephosphorylated Ser142 Rasputin is recruited to stress granules, we find that, upon amino acid starvation, only the phosphorylated Ser142 form is recruited. Furthermore, we identify Sec16, a component of the endoplasmic reticulum exit site, as a Rasputin interactor and stabilizer. Sec16 depletion results in Rasputin degradation and inhibition of stress granule formation. However, in the absence of Sec16, pharmacological stabilization of Rasputin is not enough to rescue the assembly of stress granules. This is because Sec16 specifically interacts with phosphorylated Ser142 Rasputin, the form required for stress granule formation upon amino acid starvation. Taken together, these results demonstrate that stress granule formation is fine-tuned by specific signaling cues that are unique to each stress. These results also expand the role of Sec16 as a stress response protein.

  15. Probing Phosphorus Efficient Low Phytic Acid Content Soybean Genotypes with Phosphorus Starvation in Hydroponics Growth System.

    Science.gov (United States)

    Kumar, Varun; Singh, Tiratha Raj; Hada, Alkesh; Jolly, Monica; Ganapathi, Andy; Sachdev, Archana

    2015-10-01

    Phosphorus is an essential nutrient required for soybean growth but is bound in phytic acid which causes negative effects on both the environment as well as the animal nutrition. Lowering of phytic acid levels is associated with reduced agronomic characteristics, and relatively little information is available on the response of soybean plants to phosphorus (P) starvation. In this study, we evaluated the effects of different P starvation concentrations on the phytic acid content, growth, and yield of seven mutant genotypes along with the unirradiated control, JS-335, in a hydroponics growth system. The low phytic acid containing mutant genotypes, IR-JS-101, IR-DS-118, and IR-V-101, showed a relatively high growth rate in low P concentration containing nutrient solution (2 μM), whereas the high P concentration (50 μM) favored the growth of IR-DS-111 and IR-DS-115 mutant genotypes containing moderate phytate levels. The mutant genotypes with high phytic acid content, IR-DS-122, IR-DS-114, and JS-335, responded well under P starvation and did not have any significant effect on the growth and yield of plants. Moreover, the reduction of P concentration in nutrient solution from 50 to 2 μM also reduced the phytic acid content in the seeds of all the soybean genotypes under study. The desirable agronomic performance of low phytic acid containing mutant genotype IR-DS-118 reported in this study suggested it to be a P-efficient genotype which could be considered for agricultural practices under P limiting soils.

  16. Effects of serum starvation on radiosensitivity, proliferation and apoptosis in four human tumor cell lines with different p53 status

    International Nuclear Information System (INIS)

    Oya, N.; Zoelzer, F.; Werner, F.; Streffer, C.

    2003-01-01

    Purpose: The effects of serum starvation on radiation sensitivity, cell proliferation and apoptosis were investigated with particular consideration of the p53 status. Material and Methods: Four human tumor cell lines, Be11 (melanoma, p53 wild-type), MeWo (melanoma, p53 mutant), 4197 (squamous cell carcinoma, p53 wild-type) and 4451 (squamous cell carcinoma, p53 mutant), were used. After the cells had been incubated in starvation medium (0.5% FCS) for 1-6 days, changes in cell cycle distribution, induction of apoptosis and necrosis, and changes in radiation sensitivity were assessed by two-parameter flow cytometric measurements of DNA content/BrdU labeling, two-parameter flow cytometric measurements of DNA-dye-exclusion/Annexin V binding, and a conventional colony assay, respectively. Results: p53 wild-type cell lines showed a decrease in the BrdU labeling index and an increase in the apoptotic cell frequency in starvation medium. p53 mutant cell lines showed a decrease in the BrdU labeling index but no evidence of apoptosis. These cells went into necrosis instead. The radiation sensitivity was increased in 4451 and slightly decreased in Be11 and 4197 in starvation medium. Conclusion: These data suggest a functional involvement of p53 in starvation-induced G1-block and apoptosis in tumor cells. Altered radiosensitivity after culture in starvation medium seemed to be explained at least in part by the starvation-induced G1-block. The frequency of starvation-induced apoptosis or necrosis was not correlated with radiation sensitivity. (orig.)

  17. Body size mediated starvation resistance in an insect predator.

    NARCIS (Netherlands)

    Gergs, A.; Jager, T.

    2014-01-01

    Summary: Individual organisms have to endure transient periods of low-food supply with consequences for growth, reproduction and survival. To resist starvation, animals usually store resources in their bodies: the larger the animals are, the more resources they can carry, but the more energy they

  18. Metabolite Profiling of Low-P Tolerant and Low-P Sensitive Maize Genotypes under Phosphorus Starvation and Restoration Conditions.

    Directory of Open Access Journals (Sweden)

    Arshid Hussain Ganie

    Full Text Available Maize (Zea mays L. is one of the most widely cultivated crop plants. Unavoidable economic and environmental problems associated with the excessive use of phosphatic fertilizers demands its better management. The solution lies in improving the phosphorus (P use efficiency to sustain productivity even at low P levels. Untargeted metabolomic profiling of contrasting genotypes provides a snap shot of whole metabolome which differs under specific conditions. This information provides an understanding of the mechanisms underlying tolerance to P stress and the approach for increasing P-use-efficiency.A comparative metabolite-profiling approach based on gas chromatography-mass spectrometry (GC/MS was applied to investigate the effect of P starvation and its restoration in low-P sensitive (HM-4 and low-P tolerant (PEHM-2 maize genotypes. A comparison of the metabolite profiles of contrasting genotypes in response to P-deficiency revealed distinct differences among low-P sensitive and tolerant genotypes. Another set of these genotypes were grown under P-restoration condition and sampled at different time intervals (3, 5 and 10 days to investigate if the changes in metabolite profile under P-deficiency was restored. Significant variations in the metabolite pools of these genotypes were observed under P-deficiency which were genotype specific. Out of 180 distinct analytes, 91 were identified. Phosphorus-starvation resulted in accumulation of di- and trisaccharides and metabolites of ammonium metabolism, specifically in leaves, but decreased the levels of phosphate-containing metabolites and organic acids. A sharp increase in the concentrations of glutamine, asparagine, serine and glycine was observed in both shoots and roots under low-P condition.The new insights generated on the maize metabolome in response to P-starvation and restoration would be useful towards improvement of the P-use efficiency in maize.

  19. Setting constraints on the nature and origin of the two major hydrous sulfates on Mars: Monohydrated and polyhydrated sulfates

    Science.gov (United States)

    Wang, Alian; Jolliff, Bradley L.; Liu, Yang; Connor, Kathryn

    2016-04-01

    Monohydrated Mg sulfate (MgSO4·H2O) and polyhydrated sulfate are the most common and abundant hydrous sulfates observed thus far on Mars. They are widely distributed and coexist in many locations. On the basis of results from two new sets of experiments, in combination with past experimental studies and the subsurface salt mineralogy observed at a saline playa (Dalangtan, DLT) in a terrestrial analogue hyperarid region on the Tibet Plateau, we can now set new constraints on the nature and origin of these two major Martian sulfates. Starkeyite (MgSO4·4H2O) is the best candidate for polyhydrated sulfate. MgSO4·H2O in the form of "LH-1w," generated from dehydration of Mg sulfates with high degrees of hydration, is the most likely mineral form for the majority of Martian monohydrated Mg sulfate. Two critical properties of Mg sulfates are responsible for the coexistence of these two phases that have very different degrees of hydration: (1) the metastability of a substructural unit in starkeyite at relatively low temperatures, and (2) catalytic effects attributed to coprecipitated species (sulfates, chlorides, oxides, and hydroxides) from chemically complex brines that help overcome the metastability of starkeyite. The combination of these two properties controls the coexistence of the LH-1w layer and starkeyite layers at many locations on Mars, which sometimes occur in an interbedded stratigraphy. The structural H2O held by these two broadly distributed sulfates represents a large H2O reservoir at the surface and in the shallow subsurface on current Mars.

  20. Proteomic analysis of iron acquisition, metabolic and regulatory responses of Yersinia pestis to iron starvation

    Directory of Open Access Journals (Sweden)

    Fleischmann Robert D

    2010-01-01

    Full Text Available Abstract Background The Gram-negative bacterium Yersinia pestis is the causative agent of the bubonic plague. Efficient iron acquisition systems are critical to the ability of Y. pestis to infect, spread and grow in mammalian hosts, because iron is sequestered and is considered part of the innate host immune defence against invading pathogens. We used a proteomic approach to determine expression changes of iron uptake systems and intracellular consequences of iron deficiency in the Y. pestis strain KIM6+ at two physiologically relevant temperatures (26°C and 37°C. Results Differential protein display was performed for three Y. pestis subcellular fractions. Five characterized Y. pestis iron/siderophore acquisition systems (Ybt, Yfe, Yfu, Yiu and Hmu and a putative iron/chelate outer membrane receptor (Y0850 were increased in abundance in iron-starved cells. The iron-sulfur (Fe-S cluster assembly system Suf, adapted to oxidative stress and iron starvation in E. coli, was also more abundant, suggesting functional activity of Suf in Y. pestis under iron-limiting conditions. Metabolic and reactive oxygen-deactivating enzymes dependent on Fe-S clusters or other iron cofactors were decreased in abundance in iron-depleted cells. This data was consistent with lower activities of aconitase and catalase in iron-starved vs. iron-rich cells. In contrast, pyruvate oxidase B which metabolizes pyruvate via electron transfer to ubiquinone-8 for direct utilization in the respiratory chain was strongly increased in abundance and activity in iron-depleted cells. Conclusions Many protein abundance differences were indicative of the important regulatory role of the ferric uptake regulator Fur. Iron deficiency seems to result in a coordinated shift from iron-utilizing to iron-independent biochemical pathways in the cytoplasm of Y. pestis. With growth temperature as an additional variable in proteomic comparisons of the Y. pestis fractions (26°C and 37°C, there was

  1. Pavement mechanic response of sulfate saline soil subgrade section based on fluid–structure interaction model

    OpenAIRE

    Xueying Zhao; Aiqin Shen; Yinchuang Guo; Peng Li; Zhenhua Lv

    2017-01-01

    It is a consensus that salt heaving and frost heaving are urgent and typical distress in the sulfate saline soil area. To further investigate the microscopic performance of pavement structure in this special area, Jinan-Dongying Freeway in Shandong Province is selected as a case study engineering and the mechanic responses under salt heaving, frost heaving and traffic loads were analyzed through the finite element (FE) Program (ANSYS). In this paper, the process of salt heaving and frost heav...

  2. Nitrogen Starvation and TorC1 Inhibition Differentially Affect Nuclear Localization of the Gln3 and Gat1 Transcription Factors Through the Rare Glutamine tRNACUG in Saccharomyces cerevisiae

    Science.gov (United States)

    Tate, Jennifer J.; Rai, Rajendra; Cooper, Terrance G.

    2015-01-01

    A leucine, leucyl-tRNA synthetase–dependent pathway activates TorC1 kinase and its downstream stimulation of protein synthesis, a major nitrogen consumer. We previously demonstrated, however, that control of Gln3, a transcription activator of catabolic genes whose products generate the nitrogenous precursors for protein synthesis, is not subject to leucine-dependent TorC1 activation. This led us to conclude that excess nitrogen-dependent down-regulation of Gln3 occurs via a second mechanism that is independent of leucine-dependent TorC1 activation. A major site of Gln3 and Gat1 (another GATA-binding transcription activator) control occurs at their access to the nucleus. In excess nitrogen, Gln3 and Gat1 are sequestered in the cytoplasm in a Ure2-dependent manner. They become nuclear and activate transcription when nitrogen becomes limiting. Long-term nitrogen starvation and treatment of cells with the glutamine synthetase inhibitor methionine sulfoximine (Msx) also elicit nuclear Gln3 localization. The sensitivity of Gln3 localization to glutamine and inhibition of glutamine synthesis prompted us to investigate the effects of a glutamine tRNA mutation (sup70-65) on nitrogen-responsive control of Gln3 and Gat1. We found that nuclear Gln3 localization elicited by short- and long-term nitrogen starvation; growth in a poor, derepressive medium; Msx or rapamycin treatment; or ure2Δ mutation is abolished in a sup70-65 mutant. However, nuclear Gat1 localization, which also exhibits a glutamine tRNACUG requirement for its response to short-term nitrogen starvation or growth in proline medium or a ure2Δ mutation, does not require tRNACUG for its response to rapamycin. Also, in contrast with Gln3, Gat1 localization does not respond to long-term nitrogen starvation. These observations demonstrate the existence of a specific nitrogen-responsive component participating in the control of Gln3 and Gat1 localization and their downstream production of nitrogenous precursors

  3. Pavement mechanic response of sulfate saline soil subgrade section based on fluid–structure interaction model

    Directory of Open Access Journals (Sweden)

    Xueying Zhao

    2017-11-01

    Full Text Available It is a consensus that salt heaving and frost heaving are urgent and typical distress in the sulfate saline soil area. To further investigate the microscopic performance of pavement structure in this special area, Jinan-Dongying Freeway in Shandong Province is selected as a case study engineering and the mechanic responses under salt heaving, frost heaving and traffic loads were analyzed through the finite element (FE Program (ANSYS. In this paper, the process of salt heaving and frost heaving was divided into 3 stages and FE models were established based on fluid–structure interaction (FSI model. It is shown that under both effects of salt heaving and frost heaving, the tensile stress of asphalt surface course could be up to 96.75% of its tensile strength, which means its tensile strength was seriously inadequate; however, traffic loads could help to dramatically counteract effects of salt heaving and frost heaving, which could decrease 40–80% of the tensile stress in asphalt surface course. It is also shown that in Jinan-Dongying Freeway effects of salt heaving had slightly larger effects on pavement compared with that of frost heaving, probably because salt heaving occurred from the top to the bottom of subgrade. However, as a whole, in sulfate saline soil area, compared with general area, crack resistance of asphalt courses and foundation treatment should always be strengthened. Keywords: Sulfate saline soil subgrade, Asphalt pavement, Pavement mechanic, FEM, FSI, Cracks and bulging

  4. The intestinal microbiome of fish under starvation

    OpenAIRE

    Xia, Jun Hong; Lin, Grace; Fu, Gui Hong; Wan, Zi Yi; Lee, May; Wang, Le; Liu, Xiao Jun; Yue, Gen Hua

    2014-01-01

    Background Starvation not only affects the nutritional and health status of the animals, but also the microbial composition in the host’s intestine. Next-generation sequencing provides a unique opportunity to explore gut microbial communities and their interactions with hosts. However, studies on gut microbiomes have been conducted predominantly in humans and land animals. Not much is known on gut microbiomes of aquatic animals and their changes under changing environmental conditions. To add...

  5. Opiate-like excitatory effects of steroid sulfates and calcium-complexing agents given cerebroventricularly.

    Science.gov (United States)

    LaBella, F S; Havlicek, V; Pinsky, C

    1979-01-12

    Intracerebroventricular administration of 10--20 microgram of steroid-O-sulfates induced hypermotility, agitation, salivation, EEG abnormalities, stereotypies, wet dog shakes and seizures. Equivalent effects resulted from 30--200 microgram morphine sulfate (H2SO4 salt), 50 microgram EGTA or 300--400 microgram of sodium sulfate or phosphate, but not chloride, nitrate or acetate. Non-steroid sulfates, steroid glucuronides and steroid phosphates were inactive. Naloxone, previously found to antagonize the excitatory effects of androsterone sulfate, failed to antagonize those of cortisol sulfate, sodium sulfate or EGTA. These findings suggest a role for extracellular calcium ions and for sulfate derived from circulating steroids in central responses to opiates.

  6. It is not all about regeneration: Planarians striking power to stand starvation.

    Science.gov (United States)

    Felix, Daniel A; Gutiérrez-Gutiérrez, Óscar; Espada, Lilia; Thems, Anne; González-Estévez, Cristina

    2018-05-02

    All living forms, prokaryotes as eukaryotes, have some means of adaptation to food scarcity, which extends the survival chances under extreme environmental conditions. Nowadays we know that dietary interventions, including fasting, extends lifespan of many organisms and can also protect against age-related diseases including in humans. Therefore, the capacity of adapting to periods of food scarcity may have evolved billions of years ago not only to allow immediate organismal survival but also to be able to extend organismal lifespan or at least to lead to a healthier remaining lifespan. Planarians have been the center of attention since more than two centuries because of their astonishing power of full body regeneration that relies on a large amount of adult stem cells or neoblasts. However, they also present an often-overlooked characteristic. They are able to stand long time starvation. Planarians have adapted to periods of fasting by shrinking or degrowing. Here we will review the published data about starvation in planarians and conclude with the possibility of starvation being one of the processes that rejuvenate the planarian, thus explaining the historical notion of non-ageing planarians. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Tumor necrosis factor-α attenuates starvation-induced apoptosis through upregulation of ferritin heavy chain in hepatocellular carcinoma cells

    International Nuclear Information System (INIS)

    Kou, Xingrui; Zhao, Qiudong; Zhao, Xue; Li, Rong; Wei, Lixin; Wu, Mengchao; Jing, Yingying; Deng, Weijie; Sun, Kai; Han, Zhipeng; Ye, Fei; Yu, Guofeng; Fan, Qingmin; Gao, Lu

    2013-01-01

    Tumor microenviroment is characteristic of inflammation, ischemia and starvation of nutrient. TNF-α, which is an extraordinarily pleiotropic cytokine, could be an endogenous tumor promoter in some tumor types. The basic objective of this study was to investigate the effects of TNF-α on the cell viability and apoptosis of hepatocellular carcinoma cells under serum starvation, and to identify the molecular mechanisms involved. For this purpose, five different concentrations of TNF-α and two different serum settings (serum-cultured and serum-deprived) were used to investigate the effects of TNF-α on the cell viability and apoptosis of Hep3B and SMMC-7721 cells. TNF-α (10 ng/ml) attenuated serum starvation-induced apoptosis of hepatocellular carcinoma cells, and autophagy conferred this process. BAY11-7082, a specific inhibitor of NF-κB, reversed the suppression of serum starvation-induced apoptosis by TNF-α. Moreover, TNF-α-induced NF-κB transactivation was suppressed by autophagy inhibitor 3-MA. In addition, TNF-α up-regulated Ferritin heavy chain (FHC) transiently by NF-κB activation and FHC levels were correlated with the TNF-α-induced protection against serum starvation-mediated apoptosis of hepatocellular carcinoma cells. Furthermore, FHC-mediated inhibition of apoptosis depended on suppressing ROS accumulation. Our findings suggested that autophagy conferred the TNF-α protection against serum starvation-mediated apoptosis of hepatocellular carcinoma cells, the mechanism involved with the activation of the TNF-α/ NF-κB /FHC signaling pathway

  8. The effect of starvation on the larval behavior of two forensically important species of blow flies (Diptera: Calliphoridae).

    Science.gov (United States)

    Singh, Devinder; Bala, Madhu

    2009-12-15

    The postfeeding larval stage in blow flies is generally an irreversible condition when the fully grown third instar larvae stop feeding and give no response towards food. The larvae of most species then disperse away from their feeding medium and pupariate. There are several cases reported about the use of postfeeding larvae as forensic evidence. It is a matter of common observation that the postfeeding stage can be reached earlier than the expected time if food becomes unavailable. However, no information is available on whether postfeeding stage induced by scarcity of food is also irreversible. Similarly, the minimum period of development required by the larvae of different blow flies species to enable their survival as postfeeding larvae and pupariation in the absence of food is unknown. It was observed during the present studies that the larvae of two Chrysomya species must feed for at least 35 h at 28 degrees C in order to be capable of reaching the postfeeding stage and subsequent pupariation. Duration of the starvation period required to induce postfeeding behavior decreases with increasing age of larvae. In the case of Chrysomya megacephala, 35, 45, 55 and 65 h old larvae attained irreversible postfeeding stage after 30, 20, 12 and 2 h of starvation, respectively. Similarly, larvae of Chrysomya rufifacies that were 35, 45, 55 and 60 h old attained irreversible postfeeding stage after 25, 16, 6 and 2 h of starvation, respectively.

  9. Phosphate transporter mediated lipid accumulation in Saccharomyces cerevisiae under phosphate starvation conditions.

    Science.gov (United States)

    James, Antoni W; Nachiappan, Vasanthi

    2014-01-01

    In the current study, when phosphate transporters pho88 and pho86 were knocked out they resulted in significant accumulation (84% and 43%) of triacylglycerol (TAG) during phosphate starvation. However in the presence of phosphate, TAG accumulation was only around 45% in both pho88 and pho86 mutant cells. These observations were confirmed by radio-labeling, fluorescent microscope and RT-PCR studies. The TAG synthesizing genes encoding for acyltransferases namely LRO1 and DGA1 were up regulated. This is the first report for accumulation of TAG in pho88Δ and pho86Δ cells under phosphate starvation conditions. Copyright © 2013. Published by Elsevier Ltd.

  10. Proteomic analysis of lactose-starved Lactobacillus casei during stationary growth phase.

    Science.gov (United States)

    Hussain, M A; Knight, M I; Britz, M L

    2009-03-01

    Starvation stress is a condition that nonstarter lactic acid bacteria (NSLAB) normally encounter. This study was aimed to investigate starvation-induced proteins in Lactobacillus casei during stationary growth phase. The impact of carbohydrate starvation on L. casei GCRL163 was investigated using two different media (a modified de Man, Rogosa and Sharpe broth and a semi-defined medium). Cells were grown in the presence of excess lactose (1%) or starvation (0%) and differences in the patterns of one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis of the cytosolic protein fractions were investigated. Differentially regulated proteins were identified by MALDI-TOF/TOF mass spectrometry. Many differentially regulated proteins were enzymes of various metabolic pathways involved in carbohydrate metabolism to yield energy. Differences in protein expression were also observed in the two culture conditions tested in this experiment. Numerous glycolytic enzymes were differentially regulated under lactose starvation. The differential expression of these glycolytic enzymes suggests a potential survival strategy under harsh growth conditions (i.e. lactose starvation). This paper reports improved understanding of stress responses and survival mechanism of NSLAB under lactose-depleted cheese-ripening condition. This knowledge of how NSLAB bacteria adapt to lactose starvation could be applied to predict the performances of bacteria in other industrial applications.

  11. Mitochondrial ribosomal protein L41 mediates serum starvation-induced cell-cycle arrest through an increase of p21WAF1/CIP1

    International Nuclear Information System (INIS)

    Kim, Mi Jin; Yoo, Young A.; Kim, Hyung Jung; Kang, Seongman; Kim, Yong Geon; Kim, Jun Suk; Yoo, Young Do

    2005-01-01

    Ribosomal proteins not only act as components of the translation apparatus but also regulate cell proliferation and apoptosis. A previous study reported that MRPL41 plays an important role in p53-dependent apoptosis. It also showed that MRPL41 arrests the cell cycle by stabilizing p27 Kip1 in the absence of p53. This study found that MRPL41 mediates the p21 WAF1/CIP1 -mediated G1 arrest in response to serum starvation. The cells were released from serum starvation-induced G1 arrest via the siRNA-mediated blocking of MRPL41 expression. Overall, these results suggest that MRPL41 arrests the cell cycle by increasing the p21 WAF1/CIP1 and p27 Kip1 levels under the growth inhibitory conditions

  12. Phosphate Starvation Inducible Metabolism in Lycopersicon esculentum1

    Science.gov (United States)

    Goldstein, Alan H.; Baertlein, Dawn A.; McDaniel, Robert G.

    1988-01-01

    Both tomato (Lycopersicon esculentum cv VF 36) plants and suspension cultured cells show phosphate starvation inducible (psi) excretion of acid phosphatase (Apase). Apase excretion in vitro was proportional to the level of exogenous orthophosphate (Pi). Intracellular Apase activity remained the same in both Pi-starved and sufficient cells, while Apase excreted by the starved cells increased by as much as six times over unstressed control cells on a dry weight basis. At peak induction, 50% of total Apase was excreted. Ten day old tomato seedlings grown without Pi showed slight growth reduction versus unstressed control plants. The Pi-depleted roots showed psi enhancement of Apase activity. Severely starved seedlings (17 days) reached only one-third of the biomass of unstressed control plants but, because of a combination of psi Apase excretion by roots and a shift in biomass to this organ, they excreted 5.5 times the Apase activity of the unstressed control. Observed psi Apase excretion may be part of a phosphate starvation rescue system in plants. The utility of the visible indicator dye 5-bromo-4-chloro-3-indolyl-phosphate-p-toluidine as a phenotypic marker for plant Apase excretion is demonstrated. Images Fig. 5 PMID:16666212

  13. The Pkn22 Ser/Thr kinase in Nostoc PCC 7120: role of FurA and NtcA regulators and transcript profiling under nitrogen starvation and oxidative stress.

    Science.gov (United States)

    Yingping, Fan; Lemeille, Sylvain; González, Andrés; Risoul, Véronique; Denis, Yann; Richaud, Pierre; Lamrabet, Otmane; Fillat, Maria F; Zhang, Cheng-Cai; Latifi, Amel

    2015-07-29

    The filamentous cyanobacterium Nostoc sp. strain PCC 7120 can fix N2 when combined nitrogen is not available. Furthermore, it has to cope with reactive oxygen species generated as byproducts of photosynthesis and respiration. We have previously demonstrated the synthesis of Ser/Thr kinase Pkn22 as an important survival response of Nostoc to oxidative damage. In this study we wished to investigate the possible involvement of this kinase in signalling peroxide stress and nitrogen deprivation. Quantitative RT-PCR experiments revealed that the pkn22 gene is induced in response to peroxide stress and to combined nitrogen starvation. Electrophoretic motility assays indicated that the pkn22 promoter is recognized by the global transcriptional regulators FurA and NtcA. Transcriptomic analysis comparing a pkn22-insertion mutant and the wild type strain indicated that this kinase regulates genes involved in important cellular functions such as photosynthesis, carbon metabolism and iron acquisition. Since metabolic changes may lead to oxidative stress, we investigated whether this is the case with nitrogen starvation. Our results rather invalidate this hypothesis thereby suggesting that the function of Pkn22 under nitrogen starvation is independent of its role in response to peroxide stress. Our analyses have permitted a more complete functional description of Ser/Thr kinase in Nostoc. We have decrypted the transcriptional regulation of the pkn22 gene, and analysed the whole set of genes under the control of this kinase in response to the two environmental changes often encountered by cyanobacteria in their natural habitat: oxidative stress and nitrogen deprivation.

  14. Proteomic analysis of rainbow trout (Oncorhynchus mykiss) intestinal epithelia: physiological acclimation to short-term starvation.

    Science.gov (United States)

    Baumgarner, Bradley L; Bharadwaj, Anant S; Inerowicz, Dorota; Goodman, Angela S; Brown, Paul B

    2013-03-01

    The intestinal epithelia form the first line of defense against harmful agents in the gut lumen of most monogastric vertebrates, including teleost fishes. Previous investigations into the effect of starvation on the intestinal epithelia of teleost fishes have focused primarily on changes in morphological characteristics and targeted molecular analysis of specific enzymes. The goal of this study was to use a comprehensive approach to help reveal how the intestinal epithelia of carnivorous teleost fishes acclimate to short-term nutrient deprivation. We utilized two-dimensional gel electrophoresis (2-DE) to conduct the proteomic analysis of the mucosal and epithelial layer of the anterior gut intestinal tract (GIT) from satiation fed vs. 4 week starved rainbow trout (Oncorhynchus mykiss). A total of 40 proteins were determined to be differentially expressed and were subsequently picked for in-gel trypsin digestion. Peptide mass fingerprint analysis was conducted using matrix assisted laser desorption time-of-flight/time-of-flight. Nine of the 11 positively identified proteins were directly related to innate immunity. The expression of α-1 proteinase inhibitor decreased in starved vs. fed fish. Also, the concentration of one leukocyte elastase inhibitor (LEI) isomer decreased in starved fish, though the concentration of another LEI isomer increased in due to starvation. In addition, starvation promoted an increased concentration of the important xenobiotic-transporter p-glycoprotein. Finally, starvation resulted in a significant increase in type II keratin E2. Overall, our results indicate that starvation promoted a reduced capacity to inhibit enzymatic stress but increased xenobiotic resistance and paracellular permeability of epithelial cells in the anterior intestine of rainbow trout. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival.

    Science.gov (United States)

    Hibshman, Jonathan D; Doan, Alexander E; Moore, Brad T; Kaplan, Rebecca Ew; Hung, Anthony; Webster, Amy K; Bhatt, Dhaval P; Chitrakar, Rojin; Hirschey, Matthew D; Baugh, L Ryan

    2017-10-24

    daf-16 /FoxO is required to survive starvation in Caenorhabditis elegans , but how daf-16I FoxO promotes starvation resistance is unclear. We show that daf-16 /FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16 /FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant.

  16. daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival

    Science.gov (United States)

    Hibshman, Jonathan D; Doan, Alexander E; Moore, Brad T; Kaplan, Rebecca EW; Hung, Anthony; Webster, Amy K; Bhatt, Dhaval P; Chitrakar, Rojin; Hirschey, Matthew D

    2017-01-01

    daf-16/FoxO is required to survive starvation in Caenorhabditis elegans, but how daf-16IFoxO promotes starvation resistance is unclear. We show that daf-16/FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16/FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant. PMID:29063832

  17. Protein Kinase A Activation Promotes Cancer Cell Resistance to Glucose Starvation and Anoikis.

    Directory of Open Access Journals (Sweden)

    Roberta Palorini

    2016-03-01

    Full Text Available Cancer cells often rely on glycolysis to obtain energy and support anabolic growth. Several studies showed that glycolytic cells are susceptible to cell death when subjected to low glucose availability or to lack of glucose. However, some cancer cells, including glycolytic ones, can efficiently acquire higher tolerance to glucose depletion, leading to their survival and aggressiveness. Although increased resistance to glucose starvation has been shown to be a consequence of signaling pathways and compensatory metabolic routes activation, the full repertoire of the underlying molecular alterations remain elusive. Using omics and computational analyses, we found that cyclic adenosine monophosphate-Protein Kinase A (cAMP-PKA axis activation is fundamental for cancer cell resistance to glucose starvation and anoikis. Notably, here we show that such a PKA-dependent survival is mediated by parallel activation of autophagy and glutamine utilization that in concert concur to attenuate the endoplasmic reticulum (ER stress and to sustain cell anabolism. Indeed, the inhibition of PKA-mediated autophagy or glutamine metabolism increased the level of cell death, suggesting that the induction of autophagy and metabolic rewiring by PKA is important for cancer cellular survival under glucose starvation. Importantly, both processes actively participate to cancer cell survival mediated by suspension-activated PKA as well. In addition we identify also a PKA/Src mechanism capable to protect cancer cells from anoikis. Our results reveal for the first time the role of the versatile PKA in cancer cells survival under chronic glucose starvation and anoikis and may be a novel potential target for cancer treatment.

  18. Sulfate adsorption on goethite

    Energy Technology Data Exchange (ETDEWEB)

    Rietra, R P.J.J.; Hiemstra, T; Riemsdijk, W.H. van

    1999-10-15

    Recent spectroscopic work has suggested that only one surface species of sulfate is dominant on hematite. Sulfate is therefore a very suitable anion to test and develop adsorption models for variable charge minerals. The authors have studied sulfate adsorption on goethite covering a large range of sulfate concentrations, surface coverages, pH values, and electrolyte concentrations. Four different techniques were used to cover the entire range of conditions. For characterization at low sulfate concentrations, below the detection limit of sulfate with ICP-AES, the authors used proton-sulfate titrations at constant pH. Adsorption isotherms were studied for the intermediate sulfate concentration range. Acid-base titrations in sodium sulfate and electromobility were used for high sulfate concentrations. All the data can be modeled with one adsorbed species if it is assumed that the charge of adsorbed sulfate is spatially distributed in the interface. The charge distribution of sulfate follows directly from modeling the proton-sulfate adsorption stoichoimemtry sine this stoichiometry is independent of the intrinsic affinity constant of sulfate. The charge distribution can be related to the structure of the surface complex by use of the Pauling bond valence concept and is in accordance with the microscopic structure found by spectroscopy. The intrinsic affinity constant follows from the other measurements. Modeling of the proton-ion stoichoimetry with the commonly used 2-pK models, where adsorbed ions are treated as point charges, is possible only if at least two surface species for sulfate are used.

  19. Heparan sulfate regulates fibrillin-1 N- and C-terminal interactions

    DEFF Research Database (Denmark)

    Cain, Stuart A; Baldwin, Andrew K; Mahalingam, Yashithra

    2008-01-01

    Fibrillin-1 N- and C-terminal heparin binding sites have been characterized. An unprocessed monomeric N-terminal fragment (PF1) induced a very high heparin binding response, indicating heparin-mediated multimerization. Using PF1 deletion and short fragments, a heparin binding site was localized w......-terminal interactions with heparin/heparan sulfate directly influence cell behavior, whereas C-terminal interactions with heparin/heparan sulfate regulate elastin deposition. These data highlight how heparin/heparan sulfate controls fibrillin-1 interactions....

  20. Impact of lactose starvation on the physiology of Lactobacillus casei GCRL163 in the presence or absence of tween 80.

    Science.gov (United States)

    Al-Naseri, Ali; Bowman, John P; Wilson, Richard; Nilsson, Rolf E; Britz, Margaret L

    2013-11-01

    The global proteomic response of the nonstarter lactic acid bacteria Lactobacillus casei strain GCRL163 under carbohydrate depletion was investigated to understand aspects of its survival following cessation of fermentation. The proteome of L. casei GCRL163 was analyzed quantitatively after growth in modified MRS (with and without Tween 80) with different levels of lactose (0% lactose, starvation; 0.2% lactose, growth limiting; 1% lactose, non-growth-limited control) using gel-free proteomics. Results revealed that carbohydrate starvation lead to suppression of lactose and galactose catabolic pathways as well as pathways for nucleotide and protein synthesis. Enzymes of the glycolysis/gluconeogenesis pathway, amino acid synthesis, and pyruvate and citrate metabolism become more abundant as well as other carbohydrate catabolic pathways, suggesting increased optimization of intermediary metabolism and scavenging. Tween 80 did not affect growth yield; however, proteins related to fatty acid biosynthesis were repressed in the presence of Tween 80. The data suggest that L. casei adeptly switches to a scavenging mode, using both citrate and Tween 80, and efficiently adjusts energetic requirements when carbohydrate starved and thus can sustain survival for weeks to months. Explaining the adaptation of L. casei during lactose starvation will assist efforts to maintain viability of L. casei and extend its utility as a beneficial dietary adjunct and fermentation processing aid.

  1. Investigating temporal changes in the yeast phosphoproteome upon fatty acid starvation

    DEFF Research Database (Denmark)

    Pultz, Dennis; Bennetzen, Martin; Andersen, Jens S.

    2011-01-01

    under nutrition but not malnutrition extends the life span of multiple species, ranging from single-celled organisms like yeast to mammals. This increase in longevity by dietary restriction (DR) is coupled to profound beneficial effects on age-related pathology. Despite the number of studies on DR......Investigating stemporal changes in the yeast phosphoproteome upon fatty acid starvation Dennis Pultz*, Martin Bennetzen*, Jens S. Andersen and Nils J.Færgeman. Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark, 5230 Reducing food intake to induce...... and the physiological changes DR induces, only little is known about the genetics and signalling networks which regulate the DR response. We have recently shown that inhibition of fatty acid synthesis in Saccharomyces cerevisiae results in a dependency on autophagy in maintaining normal life span. We further believe...

  2. Knockdown of AMPKα decreases ATM expression and increases radiosensitivity under hypoxia and nutrient starvation in an SV40-transformed human fibroblast cell line, LM217.

    Science.gov (United States)

    Murata, Yasuhiko; Hashimoto, Takuma; Urushihara, Yusuke; Shiga, Soichiro; Takeda, Kazuya; Jingu, Keiichi; Hosoi, Yoshio

    2018-01-22

    Presence of unperfused regions containing cells under hypoxia and nutrient starvation contributes to radioresistance in solid human tumors. It is well known that hypoxia causes cellular radioresistance, but little is known about the effects of nutrient starvation on radiosensitivity. We have reported that nutrient starvation induced decrease of mTORC1 activity and decrease of radiosensitivity in an SV40-transformed human fibroblast cell line, LM217, and that nutrient starvation induced increase of mTORC1 activity and increase of radiosensitivity in human liver cancer cell lines, HepG2 and HuH6 (Murata et al., BBRC 2015). Knockdown of mTOR using small interfering RNA (siRNA) for mTOR suppressed radiosensitivity under nutrient starvation alone in HepG2 cells, which suggests that mTORC1 pathway regulates radiosensitivity under nutrient starvation alone. In the present study, effects of hypoxia and nutrient starvation on radiosensitivity were investigated using the same cell lines. LM217 and HepG2 cells were used to examine the effects of hypoxia and nutrient starvation on cellular radiosensitivity, mTORC1 pathway including AMPK, ATM, and HIF-1α, which are known as regulators of mTORC1 activity, and glycogen storage, which is induced by HIF-1 and HIF-2 under hypoxia and promotes cell survival. Under hypoxia and nutrient starvation, AMPK activity and ATM expression were increased in LM217 cells and decreased in HepG2 cells compared with AMPK activity under nutrient starvation alone or ATM expression under hypoxia alone. Under hypoxia and nutrient starvation, radiosensitivity was decreased in LM217 cells and increased in HepG2 cells compared with radiosensitivity under hypoxia alone. Under hypoxia and nutrient starvation, knockdown of AMPK decreased ATM activity and increased radiation sensitivity in LM217 cells. In both cell lines, mTORC1 activity was decreased under hypoxia and nutrient starvation. Under hypoxia alone, knockdown of mTOR slightly increased ATM

  3. Phospho-Rasputin Stabilization by Sec16 Is Required for Stress Granule Formation upon Amino Acid Starvation.

    Science.gov (United States)

    Aguilera-Gomez, Angelica; Zacharogianni, Margarita; van Oorschot, Marinke M; Genau, Heide; Grond, Rianne; Veenendaal, Tineke; Sinsimer, Kristina S; Gavis, Elizabeth R; Behrends, Christian; Rabouille, Catherine

    2017-07-25

    Most cellular stresses induce protein translation inhibition and stress granule formation. Here, using Drosophila S2 cells, we investigate the role of G3BP/Rasputin in this process. In contrast to arsenite treatment, where dephosphorylated Ser142 Rasputin is recruited to stress granules, we find that, upon amino acid starvation, only the phosphorylated Ser142 form is recruited. Furthermore, we identify Sec16, a component of the endoplasmic reticulum exit site, as a Rasputin interactor and stabilizer. Sec16 depletion results in Rasputin degradation and inhibition of stress granule formation. However, in the absence of Sec16, pharmacological stabilization of Rasputin is not enough to rescue the assembly of stress granules. This is because Sec16 specifically interacts with phosphorylated Ser142 Rasputin, the form required for stress granule formation upon amino acid starvation. Taken together, these results demonstrate that stress granule formation is fine-tuned by specific signaling cues that are unique to each stress. These results also expand the role of Sec16 as a stress response protein. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate.

    Science.gov (United States)

    De Jongh, Cindy M; Verberk, Maarten M; Withagen, Carien E T; Jacobs, John J L; Rustemeyer, Thomas; Kezic, Sanja

    2006-06-01

    Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

  5. Overexpression of the autophagy-related gene SiATG8a from foxtail millet (Setaria italica L.) confers tolerance to both nitrogen starvation and drought stress in Arabidopsis.

    Science.gov (United States)

    Li, Wei-wei; Chen, Ming; Zhong, Li; Liu, Jia-ming; Xu, Zhao-shi; Li, Lian-cheng; Zhou, Yong-Bin; Guo, Chang-Hong; Ma, You-Zhi

    2015-12-25

    Autophagy is an evolutionarily conserved biological process in all eukaryotes for the degradation of intracellular components for nutrient recycling. Autophagy is known to be involved in responses to low nitrogen stress in Arabidopsis. Foxtail millet has strong abiotic stress resistance to both low nutrient and drought stress. However, to date, there have only been a few genes reported to be related with abiotic stress resistance in foxtail millet. In this study, we identified an autophagy-related gene, SiATG8a, from foxtail millet. SiATG8a is mainly expressed in stems and its expression was dramatically induced by drought stress and nitrogen starvation treatments. SiATG8a was localized in the membrane and cytoplasm of foxtail millet. Overexpression of SiATG8a in Arabidopsis conferred tolerance to both nitrogen starvation and to drought stress. Under nitrogen starvation conditions, the SiATG8a transgenic plants had larger root and leaf areas and accumulated more total nitrogen than wild-type plants. The transgenic plants had lower total protein concentrations than did the WT plants. Under drought stress, the SiATG8a transgenic plants had higher survival rates, chlorophyll content, and proline content, but had lower MDA content than wild type plants. Taken together, our results represent the first identified case where overexpression of autophagy related gene can simultaneously improve plant resistance to low nitrogen and drought stresses. These findings implicate plant autophagy in plant stress responses to low nitrogen and drought and should be helpful in efforts to improve stresses resistance to nitrogen starvation and drought of crops by genetic transformation. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Impact of elevated nitrate on sulfate-reducing bacteria: A comparative study of Desulfovibrio vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    He, Q.; He, Z.; Joyner, D.C.; Joachimiak, M.; Price, M.N.; Yang, Z.K.; Yen, H.-C. B.; Hemme, C. L.; Chen, W.; Fields, M.; Stahl, D. A.; Keasling, J. D.; Keller, M.; Arkin, A. P.; Hazen, T. C.; Wall, J. D.; Zhou, J.

    2010-07-15

    Sulfate-reducing bacteria have been extensively studied for their potential in heavy-metal bioremediation. However, the occurrence of elevated nitrate in contaminated environments has been shown to inhibit sulfate reduction activity. Although the inhibition has been suggested to result from the competition with nitrate-reducing bacteria, the possibility of direct inhibition of sulfate reducers by elevated nitrate needs to be explored. Using Desulfovibrio vulgaris as a model sulfate-reducing bacterium, functional genomics analysis reveals that osmotic stress contributed to growth inhibition by nitrate as shown by the upregulation of the glycine/betaine transporter genes and the relief of nitrate inhibition by osmoprotectants. The observation that significant growth inhibition was effected by 70 mM NaNO{sub 3} but not by 70 mM NaCl suggests the presence of inhibitory mechanisms in addition to osmotic stress. The differential expression of genes characteristic of nitrite stress responses, such as the hybrid cluster protein gene, under nitrate stress condition further indicates that nitrate stress response by D. vulgaris was linked to components of both osmotic and nitrite stress responses. The involvement of the oxidative stress response pathway, however, might be the result of a more general stress response. Given the low similarities between the response profiles to nitrate and other stresses, less-defined stress response pathways could also be important in nitrate stress, which might involve the shift in energy metabolism. The involvement of nitrite stress response upon exposure to nitrate may provide detoxification mechanisms for nitrite, which is inhibitory to sulfate-reducing bacteria, produced by microbial nitrate reduction as a metabolic intermediate and may enhance the survival of sulfate-reducing bacteria in environments with elevated nitrate level.

  7. Effect of Different Starvation Levels on Cognitive Ability in Mice

    Science.gov (United States)

    Li, Xiaobing; Zhi, Guoguo; Yu, Yi; Cai, Lingyu; Li, Peng; Zhang, Danhua; Bao, Shuting; Hu, Wenlong; Shen, Haiyan; Song, Fujuan

    2018-01-01

    Objective: To study the effect of different starvation levels on cognitive ability in mice. Method: Mice were randomly divided into four groups: normal group, dieting group A, dieting group B, dieting group C. The mice of normal group were given normal feeding amount, the rest of groups were given 3/4 of normal feeding amount, 2/4 of normal feeding amount and 1/4 of normal feeding amount. After feeding mice four days, the weight was observed and T-maze experiment, Morris water maze test, open field test and Serum Catalase activity were detected. Result: Compared with the normal group, the correct rate of the intervention group in the T-maze experiment was decreased and dieting group A> dieting group B> dieting group C. In the Morris water maze test, Compared with the normal group, the correct rate of the intervention group was increased. Among these three intervention groups, dieting group A had the highest correct rate and the difference of dieting group B and dieting group C were similar. In the open field test, Compared with the normal group, the exploration rate of the surrounding environment in the intervention group was increased. In the Serum Catalase test, Compared with the normal group, the activities of serum peroxidase in the intervention groups were decreased and dieting group A> dieting group B> dieting group C. Conclusion: A certain level of starvation could affect the cognitive ability of mice. In a certain range, the level of starvation is inversely proportional to cognitive ability in mice.

  8. Damage modelling in concrete subject to sulfate attack

    Directory of Open Access Journals (Sweden)

    N. Cefis

    2014-07-01

    Full Text Available In this paper, we consider the mechanical effect of the sulfate attack on concrete. The durability analysis of concrete structures in contact to external sulfate solutions requires the definition of a proper diffusion-reaction model, for the computation of the varying sulfate concentration and of the consequent ettringite formation, coupled to a mechanical model for the prediction of swelling and material degradation. In this work, we make use of a two-ions formulation of the reactive-diffusion problem and we propose a bi-phase chemo-elastic damage model aimed to simulate the mechanical response of concrete and apt to be used in structural analyses.

  9. Biological functions of iduronic acid in chondroitin/dermatan sulfate.

    Science.gov (United States)

    Thelin, Martin A; Bartolini, Barbara; Axelsson, Jakob; Gustafsson, Renata; Tykesson, Emil; Pera, Edgar; Oldberg, Åke; Maccarana, Marco; Malmstrom, Anders

    2013-05-01

    The presence of iduronic acid in chondroitin/dermatan sulfate changes the properties of the polysaccharides because it generates a more flexible chain with increased binding potentials. Iduronic acid in chondroitin/dermatan sulfate influences multiple cellular properties, such as migration, proliferation, differentiation, angiogenesis and the regulation of cytokine/growth factor activities. Under pathological conditions such as wound healing, inflammation and cancer, iduronic acid has diverse regulatory functions. Iduronic acid is formed by two epimerases (i.e. dermatan sulfate epimerase 1 and 2) that have different tissue distribution and properties. The role of iduronic acid in chondroitin/dermatan sulfate is highlighted by the vast changes in connective tissue features in patients with a new type of Ehler-Danlos syndrome: adducted thumb-clubfoot syndrome. Future research aims to understand the roles of the two epimerases and their interplay with the sulfotransferases involved in chondroitin sulfate/dermatan sulfate biosynthesis. Furthermore, a better definition of chondroitin/dermatan sulfate functions using different knockout models is needed. In this review, we focus on the two enzymes responsible for iduronic acid formation, as well as the role of iduronic acid in health and disease. © 2013 The Authors Journal compilation © 2013 FEBS.

  10. Phosphate-dependent root system architecture responses to salt stress

    KAUST Repository

    Kawa, Dorota; Julkowska, Magdalena; Montero Sommerfeld, Hector; Horst, Anneliek ter; Haring, Michel A; Testerink, Christa

    2016-01-01

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  11. Phosphate-dependent root system architecture responses to salt stress

    KAUST Repository

    Kawa, Dorota

    2016-05-20

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  12. Periodate Oxidation for Sulfated Glycosaminoglycans, with Special Reference to the Position of Extra Sulfate Groups in Chondroitin Polysulfates, Chondroitin Sulfate D and Chondroitin Sulfate K

    OpenAIRE

    Seno, Nobuko; Murakami, Keiko; Shibusawa, Haru

    1981-01-01

    The optimum conditions for periodate oxidation of sulfated disaccharides were investigated to determine the position of extra sulfate groups on the saturated disulfated disaccharides obtained from chondroitin polysulfates, chondroitin sulfates D and K. Under the conditions: 2mM saturated disulfated disaccharide with 20mM sodium periodate at 37°in the dark, the uronic acid residue in the disulfated disaccharide from chondroitin sulfate D was rapidly and completely destroyed, whereas that in th...

  13. Analysis of accelerated degradation of a HT-PEM fuel cell caused by cell reversal in fuel starvation condition

    DEFF Research Database (Denmark)

    Zhou, Fan; Andreasen, Søren Juhl; Kær, Søren Knudsen

    2015-01-01

    This paper reports an accelerated degradation test of a high temperature PEM fuel cell under repeated H2 starvation condition. The H2 stoichiometry is cycled between 3.0 and 0.8 every 2 min during the test. The experimental results show that the polarity of the fuel cell is reversed under H2......, there is only a slight decrease in open circuit voltage of the fuel cell which implies the membrane is not affected by the test. The electrochemical impedance spectrum measurement shows that the H2 starvation can cause significant increase in the ohmic resistance and charge transfer resistance. By looking...... starvation condition, and the cell performance indicated by cell voltage at H2 stoichiometry of 3.0 declines from 0.59 V to 0.41 V in 19 cycles. Since CO2 is detected in anode exhaust under H2 starvation condition, carbon corrosion is believed to be the reason for the degradation in this test. After the test...

  14. Evidence for the Adverse Effect of Starvation on Bone Quality: A Review of the Literature

    OpenAIRE

    Kueper, Janina; Beyth, Shaul; Liebergall, Meir; Kaplan, Leon; Schroeder, Josh E.

    2015-01-01

    Malnutrition and starvation's possible adverse impacts on bone health and bone quality first came into the spotlight after the horrors of the Holocaust and the ghettos of World War II. Famine and food restrictions led to a mean caloric intake of 200?800 calories a day in the ghettos and concentration camps, resulting in catabolysis and starvation of the inhabitants and prisoners. Severely increased risks of fracture, poor bone mineral density, and decreased cortical strength were noted in sev...

  15. Fed-batch cultivation of baker's yeast followed by nitrogen or carbon starvation: effects on fermentative capacity and content of trehalose and glycogen

    DEFF Research Database (Denmark)

    Jørgensen, Henning; Olsson, Lisbeth; Rønnow, B.

    2002-01-01

    , trehalose and glycogen. Nitrogen starvation triggered the accumulation of trehalose and glycogen. After 8 h of starvation, the content of trehalose and glycogen was increased 4-fold and 2-fold, respectively. Carbon starvation resulted in a partial conversion of glycogen into trehalose. The trehalose content...... increased from 45 to 64 mg (g dry-weight)(-1), whereas the glycogen content in the same period was reduced from 55 to 5 mg (g dry-weight)(-1). Glycogen was consumed faster than trehalose during storage of the starved yeast for 1 month. Nitrogen starvation resulted in a decrease in the protein content...

  16. Delivery of vincristine sulfate-conjugated gold nanoparticles using liposomes: a light-responsive nanocarrier with enhanced antitumor efficiency

    Directory of Open Access Journals (Sweden)

    Liu Y

    2015-04-01

    Full Text Available Ying Liu,1,* Man He,1,* Mengmeng Niu,1 Yiqing Zhao,1 Yuanzhang Zhu,1 Zhenhua Li,2 Nianping Feng1 1Department of Pharmaceutical Sciences, School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China; 2Cedars-Sinai Medical Center, Los Angeles, CA, USA *These authors contributed equally to this work Abstract: Rapid drug release at the specific site of action is still a challenge for antitumor therapy. Development of stimuli-responsive hybrid nanocarriers provides a promising strategy to enhance therapeutic effects by combining the unique features of each component. The present study explored the use of drug–gold nanoparticle conjugates incorporated into liposomes to enhance antitumor efficiency. A model drug, vincristine sulfate, was physically conjugated with gold nanoparticles and verified by UV-visible and fourier transform infrared spectroscopy, and differential scanning calorimetry. The conjugates were incorporated into liposomes by film dispersion to yield nanoparticles (113.4 nm with light-responsive release properties, as shown by in vitro release studies. Intracellular uptake and distribution was studied in HeLa cells using transmission electron microscopy and confocal laser scanning microscopy. This demonstrated liposome internalization and localization in endosomal–lysosomal vesicles. Fluorescence intensity increased in cells exposed to UV light, indicating that this stimulated intracellular drug release; this finding was confirmed by quantitative analyses using flow cytometry. Antitumor efficacy was evaluated in HeLa cells, both in culture and in implants in vivo in nude mice. HeLa cell viability assays showed that light exposure enhanced liposome cytotoxicity and induction of apoptosis. Furthermore, treatment with the prepared liposomes coupled with UV light exposure produced greater antitumor effects in nude mice and reduced side effects, as compared with free vincristine sulfate

  17. A phosphate-starvation-inducible outermembrane protein of Pseudomonas fluorescens Ag1 as an immunological phosphate-starvation marker

    DEFF Research Database (Denmark)

    Leopold, Kristine; Jacobsen, Susanne; Nybroe, Ole

    1997-01-01

    A phosphate-starvation-inducible outer-membrane protein of Pseudomonas fluorescens Ag1, expressed at phosphate concentrations below0.08-0.13 mM, was purified and characterized. The purification method involved separation of outer-membrane proteins by SDS-PAGE andextraction of the protein from...... nitrocellulose or PVDF membranes after electrotransfer of proteins to the membranes. The N-terminal amino acidsequence of the purified protein, called Psi1, did not show homology to any known proteins, and in contrast to the phosphate-specific porin OprP ofP. aeruginosa its mobility in SDS-PAGE was not affected...

  18. The heparin/heparan sulfate sequence that interacts with cyclophilin B contains a 3-O-sulfated N-unsubstituted glucosamine residue.

    Science.gov (United States)

    Vanpouille, Christophe; Deligny, Audrey; Delehedde, Maryse; Denys, Agnès; Melchior, Aurélie; Liénard, Xavier; Lyon, Malcolm; Mazurier, Joël; Fernig, David G; Allain, Fabrice

    2007-08-17

    Many of the biological functions of heparan sulfate (HS) proteoglycans can be attributed to specialized structures within HS moieties, which are thought to modulate binding and function of various effector proteins. Cyclophilin B (CyPB), which was initially identified as a cyclosporin A-binding protein, triggers migration and integrin-mediated adhesion of peripheral blood T lymphocytes by a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsible for the specific binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that binding of CyPB was dependent on the presence of N-unsubstituted glucosamine residues (GlcNH2), which have been reported to be precursors for sulfation by 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to be the main 3-OST isoenzyme expressed in peripheral blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 by RNA interference potently reduced CyPB binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could be a key modification that provides specialized HS structures for CyPB binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS by 3-OST-3 also provides binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage between the HS sequences involved in CyPB binding and viral infection.

  19. Silicon Promotes Growth of Brassica napus L. and Delays Leaf Senescence Induced by Nitrogen Starvation

    Directory of Open Access Journals (Sweden)

    Cylia Haddad

    2018-04-01

    Full Text Available Silicon (Si is the second most abundant element in soil and has several beneficial effects, especially in plants subjected to stress conditions. However, the effect of Si in preventing nitrogen (N starvation in plants is poorly documented. The aim of this work was to study the effect of a short Si supply duration (7 days on growth, N uptake, photosynthetic activity, and leaf senescence progression in rapeseed subjected (or not to N starvation. Our results showed that after 1 week of Si supply, Si improves biomass and increases N uptake and root expression of a nitrate transporter gene. After 12 days of N starvation, compared to -Si plants, mature leaf from +Si plants showed a high chlorophyll content, a maintain of net photosynthetic activity, a decrease of oxidative stress markers [hydrogen peroxide (H2O2 and malondialdehyde (MDA] and a significant delay in senescence. When N-deprived plants were resupplied with N, a greening again associated with an increase of photosynthetic activity was observed in mature leaves of plants pretreated with Si. Moreover, during the duration of N resupply, an increase of N uptake and nitrate transporter gene expression were observed in plants pretreated with Si. In conclusion, this study has shown a beneficial role of Si to alleviate damage associated with N starvation and more especially its role in delaying of leaf senescence.

  20. Chondroitin 4-O-Sulfotransferase Is Indispensable for Sulfation of Chondroitin and Plays an Important Role in Maintaining Normal Life Span and Oxidative Stress Responses in Nematodes*

    Science.gov (United States)

    Izumikawa, Tomomi; Dejima, Katsufumi; Watamoto, Yukiko; Nomura, Kazuko H.; Kanaki, Nanako; Rikitake, Marika; Tou, Mai; Murata, Daisuke; Yanagita, Eri; Kano, Ai; Mitani, Shohei; Nomura, Kazuya; Kitagawa, Hiroshi

    2016-01-01

    Chondroitin sulfate (CS)/chondroitin (Chn) chains are indispensable for embryonic cell division and cytokinesis in the early developmental stages in Caenorhabditis elegans and mice, whereas heparan sulfate (HS) is essential for axon guidance during nervous system development. These data indicate that the fundamental functions of CS and HS are conserved from worms to mammals and that the function of CS/Chn differs from that of HS. Although previous studies have shown that C. elegans produces HS and non-sulfated Chn, whether the organism produces CS remains unclear. Here, we demonstrate that C. elegans produces a small amount of 4-O-sulfated Chn and report the identification of C41C4.1, an orthologue of the human chondroitin 4-O-sulfotransferase gene. Loss of C41C4.1 in C. elegans resulted in a decline in 4-O-sulfation of CS and an increase in the number of sulfated units in HS. C41C4.1 deletion mutants exhibited reduced survival rates after synchronization with sodium hypochlorite. Collectively, these results show for the first time that CS glycans are present in C. elegans and that the Chn 4-O-sulfotransferase responsible for the sulfation plays an important role in protecting nematodes from oxidative stress. PMID:27645998

  1. Effect of starvation, diabetes and insulin on the casein kinase 2 from rat liver cytosol.

    OpenAIRE

    Martos, C; Plana, M; Guasch, M D; Itarte, E

    1985-01-01

    Starvation, diabetes and insulin did not alter the concentration of casein kinases in rat liver cytosol. However, the Km for casein of casein kinase 2 from diabetic rats was about 2-fold lower than that from control animals. Administration of insulin to control rats did not alter this parameter, but increased the Km for casein of casein kinase 2 in diabetic rats. Starvation did not affect the kinetic constants of casein kinases. The effect of diabetes on casein kinase 2 persisted after partia...

  2. Influence of thymine starvation on UV mutability of Escherichia coli B/r Hcr/sup +/ thy/sup -/ trp/sup -/

    Energy Technology Data Exchange (ETDEWEB)

    Balgavy, P; Turek, R [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Vyskumny Ustav Onkologicky

    1976-01-01

    Escherichia coli B/r Hcr/sup +/ thy/sup -/ trp/sup -/ cells were cultivated in a synthetic glucose medium supplemented with 2 ..mu..g/ml thymine and 14 ..mu..g/ml tryptophan until the beginning of the exponential growth phase. After filtration and washing the cells were thymine starved for different periods of time. During short-term starvation (about 40 minutes) the cells did not die and the frequency of Trp/sup +/ revertants as determined on the synthetic glucose medium supplemented with 2 ..mu..g/ml thymine and 0.75 ..mu..g/ml tryptophan solidified with agar did not increase. From the 45th min of starvation cells died exponentially and at the same time the fraction of Trp/sup +/ revertants in the population increased. During short-term starvation the sensitivity of cells to ultraviolet radiation become enhanced, at the same time one could see an increase of frequency of ''mutation-frequency-decline''-stable ultraviolet induced Trp/sup +/ revertants. Is is supposed that short-term thymine starvation affects the coordination of the rec/sup +/ and polAl/sup +/ systems participating in the uvr/sup +/ dependent DNA repair synthesis in favour of the rec/sup +/ system, incidentally starvation may affect the error-free postreplication repair in which the products of the uvr/sup +/ and rec/sup +/ genes participate.

  3. The implications of starvation induced psychological changes for the ethical treatment of hunger strikers.

    Science.gov (United States)

    Fessler, D M T

    2003-08-01

    To evaluate existing ethical guidelines for the treatment of hunger strikers in light of findings on psychological changes that accompany the cessation of food intake. Electronic databases were searched for (a) editorials and ethical proclamations on hunger strikers and their treatment; (b) studies of voluntary and involuntary starvation, and (c) legal cases pertaining to hunger striking. Additional studies were gathered in a snowball fashion from the published material cited in these databases. Material was included if it (a) provided ethical or legal guidelines; (b) shed light on psychological changes accompanying starvation, or (c) illustrated the practice of hunger striking. Authors' observations, opinions, and conclusions were noted. Although the heterogeneous nature of the sources precluded statistical analysis, starvation appears to be accompanied by marked psychological changes. Some changes clearly impair competence, in which case physicians are advised to follow advance directives obtained early in the hunger strike. More problematic are increases in impulsivity and aggressivity, changes which, while not impairing competence, enhance the likelihood that patients will starve themselves to death.

  4. Effect of starvation and refeeding on digestive enzyme activities in sturgeon (Acipenser naccarii) and trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Furné, Miriam; García-Gallego, Manuel; Hidalgo, M Carmen; Morales, Amalia E; Domezain, Alberto; Domezain, Julio; Sanz, Ana

    2008-04-01

    The digestive enzyme activities were determined in Adriatic sturgeon and rainbow trout during starvation and refeeding period. Overall, the digestive enzyme activities are affected in the same sense in both species. The protease and lipase activities were decreased later than amylase activity. Even after 1 month of starvation, both species would be prepared to digest protein and lipids in an effective way. After 72 days of starvation, the digestive machinery of the sturgeon and of the trout shows an altered capacity to digest macronutrients. The capacity to digest proteins and lipids, after 60 days of refeeding, begins to become re-established in sturgeon and trout. In contrast, in this period, the capacity to digest carbohydrates remains depressed in both species.

  5. Significant role of organic sulfur in supporting sedimentary sulfate reduction in low-sulfate environments

    Science.gov (United States)

    Fakhraee, Mojtaba; Li, Jiying; Katsev, Sergei

    2017-09-01

    Dissimilatory sulfate reduction (DSR) is a major carbon mineralization pathway in aquatic sediments, soils, and groundwater, which regulates the production of hydrogen sulfide and the mobilization rates of biologically important elements such as phosphorus and mercury. It has been widely assumed that water-column sulfate is the main sulfur source to fuel this reaction in sediments. While this assumption may be justified in high-sulfate environments such as modern seawater, we argue that in low-sulfate environments mineralization of organic sulfur compounds can be an important source of sulfate. Using a reaction-transport model, we investigate the production of sulfate from sulfur-containing organic matter for a range of environments. The results show that in low sulfate environments (50%) of sulfate reduction. In well-oxygenated systems, porewater sulfate profiles often exhibit sub-interface peaks so that sulfate fluxes are directed out of the sediment. Our measurements in Lake Superior, the world's largest lake, corroborate this conclusion: offshore sediments act as sources rather than sinks of sulfate for the water column, and sediment DSR is supported entirely by the in-sediment production of sulfate. Sulfate reduction rates are correlated to the depth of oxygen penetration and strongly regulated by the supply of reactive organic matter; rate co-regulation by sulfate availability becomes appreciable below 500 μM level. The results indicate the need to consider the mineralization of organic sulfur in the biogeochemical cycling in low-sulfate environments, including several of the world's largest freshwater bodies, deep subsurface, and possibly the sulfate-poor oceans of the Early Earth.

  6. Seedling Establishment of Tall Fescue Exposed to Long-Term Starvation Stress

    Czech Academy of Sciences Publication Activity Database

    Pompeiano, Antonio; Damiani, C. R.; Stefanini, S.; Vernieri, S.; Reyes, T. H.; Volterrani, M.; Guglielminetti, L.

    2016-01-01

    Roč. 11, č. 11 (2016), č. článku e0166131. E-ISSN 1932-6203 Institutional support: RVO:67179843 Keywords : seedling * Tall fescue * Tall fescue exposed * starvation Subject RIV: EH - Ecology, Behaviour Impact factor: 2.806, year: 2016

  7. Proteomic analysis of acute responses to copper sulfate stress in larvae of the brine shrimp, Artemia sinica

    Science.gov (United States)

    Zhou, Qian; Wu, Changgong; Dong, Bo; Li, Fuhua; Liu, Fengqi; Xiang, Jianhai

    2010-03-01

    Proteomics was used to reveal the differential protein expression profiles of acute responses to copper sulfate exposure in larvae of Artemia sinica. Fourteen differentially displayed protein spots were detected and seven of them were identified. Three spots were up-expressed and identified: actin, heat shock protein 70, and chaperone subunit 1; three down-regulated proteins were identified: arginine kinase, elongation factor-2, and glycine-rich protein; and a newly expressed protein was identified as peroxiredoxin. The study indicates the involvement of all the differentially expressed proteins in the early responses of protein expression, and in the survival of A. sinica in the presence of copper and other heavy metals; the findings improve understanding of the organism’s adaptive responses and resistance.

  8. Regional asymmetry of metabolic and antioxidant profile in the sciaenid fish shi drum (Umbrina cirrosa white muscle. Response to starvation and refeeding

    Directory of Open Access Journals (Sweden)

    M. Carmen Hidalgo

    2017-04-01

    Full Text Available The objective of the present study is to characterize the metabolic and antioxidant profile of white muscle of shi drum in two sites of the body, anterior dorsal (AM and posterior dorsal (PM portions. In addition, it will be analyzed the possible effect of starvation and a subsequent refeeding, with two different protocols, pair feeding and ad libitum. Activities of key enzymes of intermediary metabolism and of antioxidant enzymes, as well as lipid peroxidation, as an index of oxidative stress, were evaluated. The results indicate the existence of a regional asymmetry of the metabolic capacities of the white muscle of shi drum, which is likely related to the different contribution to swimming of the body regions examined. Starvation induces a metabolic depression that is more marked in those activities that support burst swimming in PM, while those activities supporting maintenance requirements are conserved. The greatest energy demands during starvation appear to lie in AM, which showed the highest oxidative metabolism rate. The increased use of fatty acids as energy source for AM leads to oxidative stress. A period of more than four weeks of refeeding for full restoration of metabolic capacities in AM is needed, probably related to the higher muscle mass located in this region. On the contrary, all enzyme activities in PM returned to control levels in both refeeding protocols, but pair feeding seems to be advantageous since compensatory growth has been taking place without signs of oxidative stress. This work was addressed to gain knowledge on the physiology of a promising fish species in aquaculture like shi drum. The results displayed here show how the starving and further re-feeding events could generate oxidative stress situations characterized by high lipid peroxidation levels which may influence negatively on the quality of the edible part of the fish. This study opens an interesting field on this fish species which deserves being

  9. EGFR is not a major driver for osteosarcoma cell growth in vitro but contributes to starvation and chemotherapy resistance.

    Science.gov (United States)

    Sevelda, Florian; Mayr, Lisa; Kubista, Bernd; Lötsch, Daniela; van Schoonhoven, Sushilla; Windhager, Reinhard; Pirker, Christine; Micksche, Michael; Berger, Walter

    2015-11-02

    Enhanced signalling via the epidermal growth factor receptor (EGFR) is a hallmark of multiple human carcinomas. However, in recent years data have accumulated that EGFR might also be hyperactivated in human sarcomas. Aim of this study was to investigate the influence of EGFR inhibition on cell viability and its interaction with chemotherapy response in osteosarcoma cell lines. We have investigated a panel of human osteosarcoma cell lines regarding EGFR expression and downstream signalling. To test its potential applicability as therapeutic target, inhibition of EGFR by gefitinib was combined with osteosarcoma chemotherapeutics and cell viability, migration, and cell death assays were performed. Osteosarcoma cells expressed distinctly differing levels of functional EGFR reaching in some cases high amounts. Functionality of EGFR in osteosarcoma cells was proven by EGF-mediated activation of both MAPK and PI3K/AKT pathway (determined by phosphorylation of ERK1/2, AKT, S6, and GSK3β). The EGFR-specific inhibitor gefitinib blocked EGF-mediated downstream signal activation. At standard in vitro culture conditions, clinically achievable gefitinib doses demonstrated only limited cytotoxic activity, however, significantly reduced long-term colony formation and cell migration. In contrast, under serum-starvation conditions active gefitinib doses were distinctly reduced while EGF promoted starvation survival. Importantly, gefitinib significantly supported the anti-osteosarcoma activities of doxorubicin and methotrexate regarding cell survival and migratory potential. Our data suggest that EGFR is not a major driver for osteosarcoma cell growth but contributes to starvation- and chemotherapy-induced stress survival. Consequently, combination approaches including EGFR inhibitors should be evaluated for treatment of high-grade osteosarcoma patients.

  10. Chondroitin 4-O-Sulfotransferase Is Indispensable for Sulfation of Chondroitin and Plays an Important Role in Maintaining Normal Life Span and Oxidative Stress Responses in Nematodes.

    Science.gov (United States)

    Izumikawa, Tomomi; Dejima, Katsufumi; Watamoto, Yukiko; Nomura, Kazuko H; Kanaki, Nanako; Rikitake, Marika; Tou, Mai; Murata, Daisuke; Yanagita, Eri; Kano, Ai; Mitani, Shohei; Nomura, Kazuya; Kitagawa, Hiroshi

    2016-10-28

    Chondroitin sulfate (CS)/chondroitin (Chn) chains are indispensable for embryonic cell division and cytokinesis in the early developmental stages in Caenorhabditis elegans and mice, whereas heparan sulfate (HS) is essential for axon guidance during nervous system development. These data indicate that the fundamental functions of CS and HS are conserved from worms to mammals and that the function of CS/Chn differs from that of HS. Although previous studies have shown that C. elegans produces HS and non-sulfated Chn, whether the organism produces CS remains unclear. Here, we demonstrate that C. elegans produces a small amount of 4-O-sulfated Chn and report the identification of C41C4.1, an orthologue of the human chondroitin 4-O-sulfotransferase gene. Loss of C41C4.1 in C. elegans resulted in a decline in 4-O-sulfation of CS and an increase in the number of sulfated units in HS. C41C4.1 deletion mutants exhibited reduced survival rates after synchronization with sodium hypochlorite. Collectively, these results show for the first time that CS glycans are present in C. elegans and that the Chn 4-O-sulfotransferase responsible for the sulfation plays an important role in protecting nematodes from oxidative stress. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Brittlestars contain highly sulfated chondroitin sulfates/dermatan sulfates that promote fibroblast growth factor 2-induced cell signaling.

    Science.gov (United States)

    Ramachandra, Rashmi; Namburi, Ramesh B; Ortega-Martinez, Olga; Shi, Xiaofeng; Zaia, Joseph; Dupont, Sam T; Thorndyke, Michael C; Lindahl, Ulf; Spillmann, Dorothe

    2014-02-01

    Glycosaminoglycans (GAGs) isolated from brittlestars, Echinodermata class Ophiuroidea, were characterized, as part of attempts to understand the evolutionary development of these polysaccharides. A population of chondroitin sulfate/dermatan sulfate (CS/DS) chains with a high overall degree of sulfation and hexuronate epimerization was the major GAG found, whereas heparan sulfate (HS) was below detection level. Enzymatic digestion with different chondroitin lyases revealed exceptionally high proportions of di- and trisulfated CS/DS disaccharides. The latter unit appears much more abundant in one of four individual species of brittlestars, Amphiura filiformis, than reported earlier in other marine invertebrates. The brittlestar CS/DS was further shown to bind to growth factors such as fibroblast growth factor 2 and to promote FGF-stimulated cell signaling in GAG-deficient cell lines in a manner similar to that of heparin. These findings point to a potential biological role for the highly sulfated invertebrate GAGs, similar to those ascribed to HS in vertebrates.

  12. The Challenge of Appropriate Identification and Treatment of Starvation, Sarcopenia, and Cachexia: A Survey of Australian Dietitians

    OpenAIRE

    Yaxley, Alison; Miller, Michelle D.

    2011-01-01

    Malnutrition is an umbrella term that includes starvation, sarcopenia, and cachexia; however, differentiating between these terms is infrequent in clinical practice. Given that the effectiveness of treatment depends on the aetiology of unintentional weight loss, it is important that clinicians are aware of the defining characteristics. The aim of this study was to determine whether Australian dietitians understand and use the terms starvation, sarcopenia, and cachexia and provide targeted tre...

  13. Discovery of a Heparan sulfate 3- o -sulfation specific peeling reaction

    NARCIS (Netherlands)

    Huang, Yu; Mao, Yang; Zong, Chengli; Lin, Cheng; Boons, Geert Jan|info:eu-repo/dai/nl/088245489; Zaia, Joseph

    2015-01-01

    Heparan sulfate (HS) 3-O-sulfation determines the binding specificity of HS/heparin for antithrombin III and plays a key role in herpes simplex virus (HSV) infection. However, the low natural abundance of HS 3-O-sulfation poses a serious challenge for functional studies other than the two cases

  14. Effects of starvation on moult cycle and hepatopancreas of Stage I lobster (Homarus americanus) larvae

    Science.gov (United States)

    Anger, K.; Storch, V.; Anger, V.; Capuzzo, J. M.

    1985-06-01

    Effects of feeding and starvation on the moult cycle and on the ultrastructure of hepatopancreas cells were studied in Stage I lobster larvae ( Homarus americanus Milne-Edwards). The relative significance of yolk and first food was quite different in larvae originating from two females. This difference was evident also in the amounts of stored lipid in the R-cells of the larval hepatopancreas. Most larvae from one hatch were, in principle, able to develop exclusively with yolk reserves (without food) to the second instar. The larvae from the second hatch showed lecithotrophic development only to the transition between late intermoult and early premoult (Stages C/D0 of Drachs's moult cycle) of the first larval instar. When initial starvation in this group lasted for 3 days or more, the point of no return (PNR) was exceeded. After the PNR, consumption of food was still possible, but development ceased in the transition C/D0 or in late premoult (D3 4). It is suggested that these stages of the moult cycle are critical points were cessation of development and increased mortality are particularly likely in early larval lobsters under nutritional stress. Examination of hepatopancreas R-cells suggested that the PNR is caused by an irreversible loss of the ability to restore lipid reserves depleted during initial starvation. Initial periods of starvation ending before the PNR prolonged mainly Stage D0 of the same instar (I). During this delay, structural changes in the R-cells caused by the preceding period of starvation were reversed: reduced lipid inclusions, swollen mitochondria, an increased number of residual bodies indicating autolysis, and a reduction of the microvillous processes. Continually starved larvae which showed lecithotrophic development throughout the first instar and were then re-fed after moulting successfully, had later a prolonged intermoult (Stage C) period in the second instar. This shows that, despite occasional lecithotrophy, food is an important

  15. p-Cresyl sulfate and indoxyl sulfate in pediatric patients on chronic dialysis

    Directory of Open Access Journals (Sweden)

    Hye Sun Hyun

    2013-04-01

    Full Text Available &lt;b&gt;Purpose:&lt;/b&gt; Indoxyl sulfate and p- cresyl sulfate are important protein-bound uremic retention solutes whose levels can be partially reduced by renal replacement therapy. These solutes originate from intestinal bacterial protein fermentation and are associated with cardiovascular outcomes and chronic kidney disease progression. The aims of this study were to investigate the levels of indoxyl sulfate and p- cresyl sulfate as well as the effect of probiotics on reducing the levels of uremic toxins in pediatric patients on dialysis. &lt;b&gt;Methods:&lt;/b&gt; We enrolled 20 pediatric patients undergoing chronic dialysis; 16 patients completed the study. The patients underwent a 12-week regimen of VSL#3, a high-concentration probiotic preparation, and the serum levels of indoxyl sulfate and p- cresyl sulfate were measured before treatment and at 4, 8, and 12 weeks after the regimen by using fluorescence liquid chromatography. To assess the normal range of indoxyl sulfate and p- cresyl sulfate we enrolled the 16 children with normal glomerular filtration rate who had visited an outpatient clinic for asymptomatic microscopic hematuria that had been detected by a school screening in August 2011. &lt;b&gt;Results:&lt;/b&gt; The baseline serum levels of indoxyl sulfate and p- cresyl sulfate in the patients on chronic dialysis were significantly higher than those in the children with microscopic hematuria. The baseline serum levels of p- cresyl sulfate in the peritoneal dialysis group were significantly higher than those in the hemodialysis group. There were no significant changes in the levels of these uremic solutes after 12-week VSL#3 treatment in the patients on chronic dialysis. &lt;b&gt;Conclusion:&lt;/b&gt; The levels of the uremic toxins p- cresyl sulfate and indoxyl sulfate are highly elevated in pediatric patients on dialysis, but there was no significant effect by

  16. Identification of putative QTLs for seedling stage phosphorus starvation response in finger millet (Eleusine coracana L. Gaertn. by association mapping and cross species synteny analysis.

    Directory of Open Access Journals (Sweden)

    M Ramakrishnan

    Full Text Available A germplasm assembly of 128 finger millet genotypes from 18 countries was evaluated for seedling-stage phosphorus (P responses by growing them in P sufficient (Psuf and P deficient (Pdef treatments. Majority of the genotypes showed adaptive responses to low P condition. Based on phenotype behaviour using the best linear unbiased predictors for each trait, genotypes were classified into, P responsive, low P tolerant and P non-responsive types. Based on the overall phenotype performance under Pdef, 10 genotypes were identified as low P tolerants. The low P tolerant genotypes were characterised by increased shoot and root length and increased root hair induction with longer root hairs under Pdef, than under Psuf. Association mapping of P response traits using mixed linear models revealed four quantitative trait loci (QTLs. Two QTLs (qLRDW.1 and qLRDW.2 for low P response affecting root dry weight explained over 10% phenotypic variation. In silico synteny analysis across grass genomes for these QTLs identified putative candidate genes such as Ser-Thr kinase and transcription factors such as WRKY and basic helix-loop-helix (bHLH. The QTLs for response under Psuf were mapped for traits such as shoot dry weight (qHSDW.1 and root length (qHRL.1. Putative associations of these QTLs over the syntenous regions on the grass genomes revealed proximity to cytochrome P450, phosphate transporter and pectin methylesterase inhibitor (PMEI genes. This is the first report of the extent of phenotypic variability for P response in finger millet genotypes during seedling-stage, along with the QTLs and putative candidate genes associated with P starvation tolerance.

  17. Identification of putative QTLs for seedling stage phosphorus starvation response in finger millet (Eleusine coracana L. Gaertn.) by association mapping and cross species synteny analysis.

    Science.gov (United States)

    Ramakrishnan, M; Ceasar, S Antony; Vinod, K K; Duraipandiyan, V; Ajeesh Krishna, T P; Upadhyaya, Hari D; Al-Dhabi, N A; Ignacimuthu, S

    2017-01-01

    A germplasm assembly of 128 finger millet genotypes from 18 countries was evaluated for seedling-stage phosphorus (P) responses by growing them in P sufficient (Psuf) and P deficient (Pdef) treatments. Majority of the genotypes showed adaptive responses to low P condition. Based on phenotype behaviour using the best linear unbiased predictors for each trait, genotypes were classified into, P responsive, low P tolerant and P non-responsive types. Based on the overall phenotype performance under Pdef, 10 genotypes were identified as low P tolerants. The low P tolerant genotypes were characterised by increased shoot and root length and increased root hair induction with longer root hairs under Pdef, than under Psuf. Association mapping of P response traits using mixed linear models revealed four quantitative trait loci (QTLs). Two QTLs (qLRDW.1 and qLRDW.2) for low P response affecting root dry weight explained over 10% phenotypic variation. In silico synteny analysis across grass genomes for these QTLs identified putative candidate genes such as Ser-Thr kinase and transcription factors such as WRKY and basic helix-loop-helix (bHLH). The QTLs for response under Psuf were mapped for traits such as shoot dry weight (qHSDW.1) and root length (qHRL.1). Putative associations of these QTLs over the syntenous regions on the grass genomes revealed proximity to cytochrome P450, phosphate transporter and pectin methylesterase inhibitor (PMEI) genes. This is the first report of the extent of phenotypic variability for P response in finger millet genotypes during seedling-stage, along with the QTLs and putative candidate genes associated with P starvation tolerance.

  18. Co-existence of Methanogenesis and Sulfate Reduction with Common Substrates in Sulfate-Rich Estuarine Sediments

    Directory of Open Access Journals (Sweden)

    Michal Sela-Adler

    2017-05-01

    Full Text Available The competition between sulfate reducing bacteria and methanogens over common substrates has been proposed as a critical control for methane production. In this study, we examined the co-existence of methanogenesis and sulfate reduction with shared substrates over a large range of sulfate concentrations and rates of sulfate reduction in estuarine systems, where these processes are the key terminal sink for organic carbon. Incubation experiments were carried out with sediment samples from the sulfate-methane transition zone of the Yarqon (Israel estuary with different substrates and inhibitors along a sulfate concentrations gradient from 1 to 10 mM. The results show that methanogenesis and sulfate reduction can co-exist while the microbes share substrates over the tested range of sulfate concentrations and at sulfate reduction rates up to 680 μmol L-1 day-1. Rates of methanogenesis were two orders of magnitude lower than rates of sulfate reduction in incubations with acetate and lactate, suggesting a higher affinity of sulfate reducing bacteria for the available substrates. The co-existence of both processes was also confirmed by the isotopic signatures of δ34S in the residual sulfate and that of δ13C of methane and dissolved inorganic carbon. Copy numbers of dsrA and mcrA genes supported the dominance of sulfate reduction over methanogenesis, while showing also the ability of methanogens to grow under high sulfate concentration and in the presence of active sulfate reduction.

  19. Final report on the safety assessment of sodium cetearyl sulfate and related alkyl sulfates as used in cosmetics.

    Science.gov (United States)

    Fiume, Monice; Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F

    2010-05-01

    Sodium cetearyl sulfate is the sodium salt of a mixture of cetyl and stearyl sulfate. The other ingredients in this safety assessment are also alkyl salts, including ammonium coco-sulfate, ammonium myristyl sulfate, magnesium coco-sulfate, sodium cetyl sulfate, sodium coco/hydrogenated tallow sulfate, sodium coco-sulfate, sodium decyl sulfate, sodium ethylhexyl sulfate, sodium myristyl sulfate, sodium oleyl sulfate, sodium stearyl sulfate, sodium tallow sulfate, sodium tridecyl sulfate, and zinc coco-sulfate. These ingredients are surfactants used at concentrations from 0.1% to 29%, primarily in soaps and shampoos. Many of these ingredients are not in current use. The Cosmetic Ingredient Review (CIR) Expert Panel previously completed a safety assessment of sodium and ammonium lauryl sulfate. The data available for sodium lauryl sulfate and ammonium lauryl sulfate provide sufficient basis for concluding that sodium cetearyl sulfate and related alkyl sulfates are safe in the practices of use and concentration described in the safety assessment.

  20. Rare earth sulfates

    International Nuclear Information System (INIS)

    Komissarova, L.N.; Shatskij, V.M.; Pokrovskij, A.N.; Chizhov, S.M.; Bal'kina, T.I.; Suponitskij, Yu.L.

    1986-01-01

    Results of experimental works on the study of synthesis conditions, structure and physico-chemical properties of rare earth, scandium and yttrium sulfates, have been generalized. Phase diagrams of solubility and fusibility, thermodynamic and crystallochemical characteristics, thermal stability of hydrates and anhydrous sulfates of rare earths, including normal, double (with cations of alkali and alkaline-earth metals), ternary and anion-mixed sulfates of rare earths, as well as their adducts, are considered. The state of ions of rare earths, scandium and yttrium in aqueous sulfuric acid solutions is discussed. Data on the use of rare earth sulfates are given

  1. Experimental Comparison of the Behavior between Base Oil and Grease Starvation Based on Inlet Film Thickness

    Directory of Open Access Journals (Sweden)

    D. Kostal

    2017-03-01

    Full Text Available This paper deals with the experimental study of an elastohydrodynamic contact under conditions of insufficient lubricant supply. Starvation level of this type of the contact may be experimentally determined based on the position of the meniscus, but this way can't determine all levels of starvation. Consequent development in the field of tribology achieved theoretical model that can determine all levels of starvation by dependency on the thickness of the lubricant film entering the contact, but it is difficult for experimental verification. The main goal of this work is an experimental study and description of the behavior of the elastohydrodynamic contact with controlled thickness of the lubricant film at the contact input. Contact was lubricated by the base oil and the grease and compared. Results were surprising because the only differences between oil and grease were observed for more viscous lubricants at thicker film layer entering to the contact.

  2. The Hunger Games: p53 regulates metabolism upon serine starvation.

    Science.gov (United States)

    Tavana, Omid; Gu, Wei

    2013-02-05

    Cancer cells reprogram their metabolism to support a high proliferative rate. A new study shows that, upon serine starvation, the tumor suppressor p53 activates p21 to shift metabolic flux from purine biosynthesis to glutathione production, which enhances cellular proliferation and viability by combating ROS (Maddocks et al., 2013). Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Transcriptome analysis of the Populus trichocarpa-Rhizophagus irregularis Mycorrhizal Symbiosis: Regulation of Plant and Fungal Transportomes under Nitrogen Starvation.

    Science.gov (United States)

    Calabrese, Silvia; Kohler, Annegret; Niehl, Annette; Veneault-Fourrey, Claire; Boller, Thomas; Courty, Pierre-Emmanuel

    2017-06-01

    Nutrient transfer is a key feature of the arbuscular mycorrhizal (AM) symbiosis. Valuable mineral nutrients are transferred from the AM fungus to the plant, increasing its fitness and productivity, and, in exchange, the AM fungus receives carbohydrates as an energy source from the plant. Here, we analyzed the transcriptome of the Populus trichocarpa-Rhizophagus irregularis symbiosis using RNA-sequencing of non-mycorrhizal or mycorrhizal fine roots, with a focus on the effect of nitrogen (N) starvation. In R. irregularis, we identified 1,015 differentially expressed genes, whereby N starvation led to a general induction of gene expression. Genes of the functional classes of cell growth, membrane biogenesis and cell structural components were highly abundant. Interestingly, N starvation also led to a general induction of fungal transporters, indicating increased nutrient demand upon N starvation. In non-mycorrhizal P. trichocarpa roots, 1,341 genes were differentially expressed under N starvation. Among the 953 down-regulated genes in N starvation, most were involved in metabolic processes including amino acids, carbohydrate and inorganic ion transport, while the 342 up-regulated genes included many defense-related genes. Mycorrhization led to the up-regulation of 549 genes mainly involved in secondary metabolite biosynthesis and transport; only 24 genes were down-regulated. Mycorrhization specifically induced expression of three ammonium transporters and one phosphate transporter, independently of the N conditions, corroborating the hypothesis that these transporters are important for symbiotic nutrient exchange. In conclusion, our data establish a framework of gene expression in the two symbiotic partners under high-N and low-N conditions. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. Heparan sulfate biosynthesis

    DEFF Research Database (Denmark)

    Multhaupt, Hinke A B; Couchman, John R

    2012-01-01

    Heparan sulfate is perhaps the most complex polysaccharide known from animals. The basic repeating disaccharide is extensively modified by sulfation and uronic acid epimerization. Despite this, the fine structure of heparan sulfate is remarkably consistent with a particular cell type. This suggests...... that the synthesis of heparan sulfate is tightly controlled. Although genomics has identified the enzymes involved in glycosaminoglycan synthesis in a number of vertebrates and invertebrates, the regulation of the process is not understood. Moreover, the localization of the various enzymes in the Golgi apparatus has......-quality resolution of the distribution of enzymes. The EXT2 protein, which when combined as heterodimers with EXT1 comprises the major polymerase in heparan sulfate synthesis, has been studied in depth. All the data are consistent with a cis-Golgi distribution and provide a starting point to establish whether all...

  5. Usage of energy reserves in crustaceans during starvation: status and future directions.

    Science.gov (United States)

    Sánchez-Paz, Arturo; García-Carreño, Fernando; Muhlia-Almazán, Adriana; Peregrino-Uriarte, Alma B; Hernández-López, Jorge; Yepiz-Plascencia, Gloria

    2006-04-01

    In this paper, we review the current knowledge about the usage of carbohydrates, lipids and proteins as energy source by marine crustaceans during starvation. Crustaceans are a large and diverse group including some economically important species. The efforts to culture them for human consumption has prompted the interest to understand the preferences of energy sources to be applied for feed formulation and cost reduction. Important differences have been found among species and appear to be related not only to the biochemistry and physiology of nutrition, but also to the living environment of the crustaceans. Furthermore, crustaceans undergo morphological, physiological and behavioral changes due to their natural growing process that affect their feeding habits, an aspect that should be carefully considered. We discuss the current information on marine crustaceans about energy usage and describe areas of future research, where starvation studies render important insights.

  6. Durability test with fuel starvation using a Pt/CNF catalyst in PEMFC.

    Science.gov (United States)

    Jung, Juhae; Park, Byungil; Kim, Junbom

    2012-01-05

    In this study, a catalyst was synthesized on carbon nanofibers [CNFs] with a herringbone-type morphology. The Pt/CNF catalyst exhibited low hydrophilicity, low surface area, high dispersion, and high graphitic behavior on physical analysis. Electrodes (5 cm2) were prepared by a spray method, and the durability of the Pt/CNF was evaluated by fuel starvation. The performance was compared with a commercial catalyst before and after accelerated tests. The fuel starvation caused carbon corrosion with a reverse voltage drop. The polarization curve, EIS, and cyclic voltammetry were analyzed in order to characterize the electrochemical properties of the Pt/CNF. The performance of a membrane electrode assembly fabricated from the Pt/CNF was maintained, and the electrochemical surface area and cell resistance showed the same trend. Therefore, CNFs are expected to be a good support in polymer electrolyte membrane fuel cells.

  7. Dynamic metabolomics differentiates between carbon and energy starvation in recombinant Saccharomyces cerevisiae fermenting xylose

    Directory of Open Access Journals (Sweden)

    Bergdahl Basti

    2012-05-01

    , a reduced GTP/GDP ratio and accumulation of PEP and aromatic amino acids. These changes are strong indicators of carbon starvation. The XR/XDH-strain displayed few such traits. The coexistence of these traits and a stable adenylate charge indicates that xylose supplies energy to the cells but does not suppress a response similar to carbon starvation. Particular signals may play a role in the latter, of which the GTP/GMP ratio could be a candidate as it decreased significantly in both strains.

  8. Modeling of ferric sulfate decomposition and sulfation of potassium chloride during grate‐firing of biomass

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Jappe Frandsen, Flemming

    2013-01-01

    Ferric sulfate is used as an additive in biomass combustion to convert the released potassium chloride to the less harmful potassium sulfate. The decomposition of ferric sulfate is studied in a fast heating rate thermogravimetric analyzer and a volumetric reaction model is proposed to describe...... the process. The yields of sulfur oxides from ferric sulfate decomposition under boiler conditions are investigated experimentally, revealing a distribution of approximately 40% SO3 and 60% SO2. The ferric sulfate decomposition model is combined with a detailed kinetic model of gas‐phase KCl sulfation...... and a model of K2SO4 condensation to simulate the sulfation of KCl by ferric sulfate addition. The simulation results show good agreements with experiments conducted in a biomass grate‐firing reactor. The results indicate that the SO3 released from ferric sulfate decomposition is the main contributor to KCl...

  9. CD147 is increased in HCC cells under starvation and reduces cell death through upregulating p-mTOR in vitro.

    Science.gov (United States)

    Gou, Xingchun; Tang, Xu; Kong, Derek Kai; He, Xinying; Gao, Xingchun; Guo, Na; Hu, Zhifang; Zhao, Zhaohua; Chen, Yanke

    2016-01-01

    Transarterial chemoembolization (TACE) is the standard of care for treatment of intermediate hepatocellular carcinoma (HCC), however, key molecules involved in HCC cell survival and tumor metastasis post-TACE remain unclear. CD147 is a member of the immunoglobulin superfamily that is overexpressed on the surface of HCC cells and is associated with malignant potential and poor prognosis in HCC patients. In this study, using an Earle's Balanced Salt Solution medium culture model that mimics nutrient deprivation induced by TACE, we investigated the regulation of CD147 expression on HCC cells under starvation conditions and its functional effects on HCC cell death. During early stages of starvation, the expression of CD147 was considerably upregulated in SMMC7721, HepG2 and HCC9204 hepatoma cell lines at the protein levels. Downregulation of CD147 by specific small interfering RNA (siRNA) significantly promoted starvation-induced cell death. In addition, CD147 siRNA-transfected SMMC7721 cells demonstrated significantly increased levels of both apoptosis and autophagy as compared to cells transfected with control siRNA under starvation conditions, whereas no difference was observed between the two treatment groups under normal culture conditions. Furthermore, silencing of CD147 resulted in a remarkable downregulation of phosphorylated mammalian target of rapamycin (p-mTOR) in starved SMMC7721 cells. Finally, the combined treatment of starvation and anti-CD147 monoclonal antibody exhibited a synergistic HCC cell killing effect. Our study suggests that upregulation of CD147 under starvation may reduce hepatoma cell death by modulating both apoptosis and autophagy through mTOR signaling, and that CD147 may be a novel potential molecular target to improve the efficacy of TACE.

  10. Desulfobacter psychrotolerans sp. nov., a new psychrotolerant sulfate-reducing bacterium and descriptions of its physiological response to temperature changes.

    Science.gov (United States)

    Tarpgaard, Irene H; Boetius, Antje; Finster, Kai

    2006-01-01

    A psychrotrolerant acetate-oxidizing sulfate-reducing bacterium (strain akvb(T)) was isolated from sediment from the northern part of The North Sea with annual temperature fluctuations between 8 and 14 degrees C. Of the various substrates tested, strain akvb(T) grew exclusively by the oxidation of acetate coupled to the reduction of sulfate. The cells were motile, thick rods with round ends and grew in dense aggregates. Strain akvb(T) grew at temperatures ranging from -3.6 to 26.3 degrees C. Optimal growth was observed at 20 degrees C. The highest cell specific sulfate reduction rate of 6.2 fmol cell(-1) d(-1) determined by the (35)SO(2-)(40) method was measured at 26 degrees C. The temperature range of short-term sulfate reduction rates exceeded the temperature range of growth by 5 degrees C. The Arrhenius relationship for the temperature dependence of growth and sulfate reduction was linear, with two distinct slopes below the optimum temperatures of both processes. The critical temperature was 6.4 degrees C. The highest growth yield (4.3-4.5 g dry weight mol(-1) acetate) was determined at temperatures between 5 and 15 degrees C. The cellular fatty acid composition was determined with cultures grown at 4 and 20 degrees C, respectively. The relative proportion of cellular unsaturated fatty acids (e.g. 16:1omega7c) was higher in cells grown at 4 degrees C than in cells grown at 20 degrees C. The physiological responses to temperature changes showed that strain akvb(T) was well adapted to the temperature regime of the environment from which it was isolated. Phylogenetic analysis showed that strain akvb(T) is closest related to Desulfobacter hydrogenophilus, with a 16S rRNA gene sequence similarity of 98.6%. DNA-DNA-hybridization showed a similarity of 32% between D. hydrogenophilus and strain akvb(T). Based on phenotypic and DNA-based characteristics we propose that strain akvb(T) is a member of a new species, Desulfobacter psychrotolerans sp. nov.

  11. Correction: Dermatan sulfate in tunicate phylogeny: Order-specific sulfation pattern and the effect of [→4IdoA(2-Sulfateβ-1→3GalNAc(4-Sulfateβ-1→] motifs in dermatan sulfate on heparin cofactor II activity

    Directory of Open Access Journals (Sweden)

    Sugahara Kazuyuki

    2011-07-01

    Full Text Available Abstract After the publication of the work entitled "Dermatan sulfate in tunicate phylogeny: Order-specific sulfation pattern and the effect of [→4IdoA(2-Sulfateβ-1→3GalNAc(4-Sulfateβ-1→] motifs in dermatan sulfate on heparin cofactor II activity", by Kozlowski et al., BMC Biochemistry 2011, 12:29, we found that the legends to Figures 2 to 5 contain serious mistakes that compromise the comprehension of the work. This correction article contains the correct text of the legends to Figures 2 to 5.

  12. Candida albicans survival and biofilm formation under starvation conditions.

    Science.gov (United States)

    Ning, Y; Hu, X; Ling, J; Du, Y; Liu, J; Liu, H; Peng, Z

    2013-01-01

    To investigate the survival and biofilm formation capacity of Candida albicans in starvation and under anaerobic conditions. Candida albicans growth and survival were monitored in vitro for up to 8 months. Fungal suspensions from late exponential, stationary and starvation phases were incubated on human dentine, polystyrene and glass slides. Scanning electron microscopy (SEM) was used to observe the process of biofilm formation. 2,3-bis(2-Methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxyanilide inner salt (XTT) reduction assay was performed to quantify the biofilm formation capability, and confocal laser scanning microscopy (CLSM) was used to study and make semi-quantitative comparisons of the ultrastructure of biofilms formed on human dentine. 'XTT bioactivity' and 'COMSTAT results' were analysed by two-way analysis of variance (ANOVA) and one-way ANOVA, respectively. Candida albicans survived for over six months. SEM demonstrated that starving C. albicans produced mature biofilms on different substrata. C. albicans of the same growth phase incubated on human dentine displayed significantly higher biofilm formation capability than on polystyrene or glass slides (P roughness coefficient and surface/volume ratio (P < 0.05). Candida albicans cells can survive and form biofilms in anaerobic and nutrient-limited conditions and may pose a treatment challenge. © 2012 International Endodontic Journal.

  13. On the sulfation of O-desmethyltramadol by human cytosolic sulfotransferases.

    Science.gov (United States)

    Rasool, Mohammed I; Bairam, Ahsan F; Kurogi, Katsuhisa; Liu, Ming-Cheh

    2017-10-01

    Previous studies have demonstrated that sulfate conjugation is involved in the metabolism of the active metabolite of tramadol, O-desmethyltramadol (O-DMT). The current study aimed to systematically identify the human cytosolic sulfotransferases (SULTs) that are capable of mediating the sulfation of O-DMT. The sulfation of O-DMT under metabolic conditions was demonstrated using HepG2 hepatoma cells and Caco-2 human colon carcinoma cells. O-DMT-sulfating activity of thirteen known human SULTs and four human organ specimens was examined using an established sulfotransferase assay. pH-Dependency and kinetic parameters were also analyzed using, respectively, buffers at different pHs and varying O-DMT concentrations in the assays. Of the thirteen human SULTs tested, only SULT1A3 and SULT1C4 were found to display O-DMT-sulfating activity, with different pH-dependency profiles. Kinetic analysis revealed that SULT1C4 was 60 times more catalytically efficient in mediating the sulfation of O-DMT than SULT1A3 at respective optimal pH. Of the four human organ specimens tested, the cytosol prepared from the small intestine showed much higher O-DMT-sulfating activity than cytosols prepared from liver, lung, and kidney. Both cultured HepG2 and Caco-2 cells were shown to be capable of sulfating O-DMT and releasing sulfated O-DMT into cultured media. SULT1A3 and SULT1C4 were the major SULTs responsible for the sulfation of O-DMT. Collectively, the results obtained provided a molecular basis underlying the sulfation of O-DMT and contributed to a better understanding about the pharmacokinetics and pharmacodynamics of tramadol in humans. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  14. Behaviour of cementitious materials: sulfates and temperature actions

    International Nuclear Information System (INIS)

    Barbarulo, Remi

    2002-09-01

    The research work presented in this Ph.D. thesis is related to the nuclear waste underground repository concept. Concrete could be used in such a repository, and would be subjected to variations of temperature in presence of sulfate, a situation that could induce expansion of concrete. The research was lead in three parts: an experimental study of the possibility of an internal sulfate attack on mortars; an experimental study and modeling of the chemical equilibriums of the CaO-SiO 2 -Al 2 O 3 -SO 3 -H 2 O system; and a modeling of the mechanisms of internal and external sulfate attacks, and the effect of temperature. The results show that mortars can develop expansions after a steam-cure during hydration, but also when a long steam-cure is applied to one-year-old mortars, which is a new point. Ettringite precipitation can be considered as responsible for these expansions. The experimental study of the CaO-SiO 2 -Al 2 O 3 -SO 3 -H 2 O system clarified the role of Calcium Silicate Hydrates (C-S-H) on chemical equilibriums of cementitious materials. Sulfate sorption on C-S-H has been studied in detail. The quantity of sulfate bound to the C-S-H mainly depends on the sulfate concentration in solution, on the Ca/Si ratio of the C-S-H and is not significantly influenced by temperature. Aluminium inclusion in the C-S-H seems to be a significant phenomenon. Temperature increases the calcium sulfo-aluminate solubilities and thus increases sulfates concentration in solution. A modeling of the chemical system is proposed. Simulations of external sulfate attack (15 mmol/L of Na 2 SO 4 ) predict ettringite precipitation at 20 and 85±C. Simulation of internal sulfate attack was performed at a local scale (a hydrated cement grain). An initial inhomogeneity can lead, after a thermal curing at 85±C, to ettringite precipitation in zones originally free from ettringite. This new-formed ettringite could be the origin of the expansions. (author) [fr

  15. The effect of divalent salt in chondroitin sulfate solutions

    Energy Technology Data Exchange (ETDEWEB)

    Aranghel, D., E-mail: daranghe@nipne.ro [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); Extreme Light Intrastructure Nuclear Physics (ELI-NP), Reactorului 30,RO-077125, POB-MG6, Magurele-Bucharest (Romania); Badita, C. R. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); University of Bucharest, Faculty of Physics, Atomiştilor 405, CP MG - 11, RO – 077125, Bucharest-Magurele (Romania); Radulescu, A. [Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science, 85747 Garching (Germany); Moldovan, L.; Craciunescu, O. [National Institute R& D for Biological Sciences, Splaiul Independenţei 296, sector 6, cod 060031, C.P. 17-16, Bucharest (Romania); Balasoiu, M. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Reactorului 30, RO-077125, POB-MG6, Magurele-Bucharest, Romania, daranghe@nipne.ro (Romania); Joint Institute for Nuclear Research, 141980 Dubna, Moscow region (Russian Federation)

    2016-03-25

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca{sup 2+} cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca{sup 2+} by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl{sub 2}) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  16. The effect of divalent salt in chondroitin sulfate solutions

    Science.gov (United States)

    Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

    2016-03-01

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca2+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca2+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  17. The effect of divalent salt in chondroitin sulfate solutions

    International Nuclear Information System (INIS)

    Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

    2016-01-01

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca"2"+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca"2"+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl_2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  18. The significance of translation regulation in the stress response

    Science.gov (United States)

    2013-01-01

    Background The stress response in bacteria involves the multistage control of gene expression but is not entirely understood. To identify the translational response of bacteria in stress conditions and assess its contribution to the regulation of gene expression, the translational states of all mRNAs were compared under optimal growth condition and during nutrient (isoleucine) starvation. Results A genome-scale study of the translational response to nutritional limitation was performed in the model bacterium Lactococcus lactis. Two measures were used to assess the translational status of each individual mRNA: the fraction engaged in translation (ribosome occupancy) and ribosome density (number of ribosomes per 100 nucleotides). Under isoleucine starvation, half of the mRNAs considered were translationally down-regulated mainly due to decreased ribosome density. This pattern concerned genes involved in growth-related functions such as translation, transcription, and the metabolism of fatty acids, phospholipids and bases, contributing to the slowdown of growth. Only 4% of the mRNAs were translationally up-regulated, mostly related to prophagic expression in response to stress. The remaining genes exhibited antagonistic regulations of the two markers of translation. Ribosome occupancy increased significantly for all the genes involved in the biosynthesis of isoleucine, although their ribosome density had decreased. The results revealed complex translational regulation of this pathway, essential to cope with isoleucine starvation. To elucidate the regulation of global gene expression more generally, translational regulation was compared to transcriptional regulation under isoleucine starvation and to other post-transcriptional regulations related to mRNA degradation and mRNA dilution by growth. Translational regulation appeared to accentuate the effects of transcriptional changes for down-regulated growth-related functions under isoleucine starvation although m

  19. Metabolism of Seriola lalandi during Starvation as Revealed by Fatty Acid Analysis and Compound-Specific Analysis of Stable Isotopes within Amino Acids.

    Directory of Open Access Journals (Sweden)

    Fernando Barreto-Curiel

    Full Text Available Fish starvation is defined as food deprivation for a long period of time, such that physiological processes become confined to basal metabolism. Starvation provides insights in physiological processes without interference from unknown factors in digestion and nutrient absorption occurring in fed state. Juveniles of amberjack Seriola lalandi were isotopically equilibrated to a formulated diet for 60 days. One treatment consisted of fish that continued to be fed and fish in the other treatment were not fed for 35 days. The isotopic signatures prior to the beginning of and after the starvation period, for fish in the starvation and control treatments, were analysed for lipid content, fatty acid composition and isotopic analysis of bulk (EA-IRMS and of amino acids (compound specific isotope analysis, CSIA. There were three replicates for the starvation group. Fatty acid content in muscle and liver tissue before and after starvation was determined to calculate percent change. Results showed that crude lipid was the most used source of energy in most cases; the PUFAs and LC-PUFAs were highly conserved. According to the protein signature in bulk (δ15N and per amino acid (δ13C and δ15N, in muscle tissue, protein synthesis did not appear to occur substantially during starvation, whereas in liver, increases in δ13C and δ15N indicate that protein turnover occurred, probably for metabolic routing to energy-yielding processes. As a result, isotopic values of δ15N in muscle tissue do not change, whereas CSIA net change occurred in the liver tissue. During the study period of 35 days, muscle protein was largely conserved, being neither replenished from amino acid pools in the plasma and liver nor catabolized.

  20. BAG3 promoted starvation-induced apoptosis of thyroid cancer cells via attenuation of autophagy.

    Science.gov (United States)

    Li, Si; Zhang, Hai-Yan; Wang, Tian; Meng, Xin; Zong, Zhi-Hong; Kong, De-Hui; Wang, Hua-Qin; Du, Zhen-Xian

    2014-11-01

    BAG3 plays a regulatory role in a number of cellular processes. Recent studies have attracted much attention on its role in activation of selective autophagy. In addition, we have very recently reported that BAG3 is implicated in a BECN1-independent autophagy, namely noncanonical autophagy. The current study aimed to investigate the potential involvement of BAG3 in canonical autophagy triggered by Earle's Balanced Salt Solution (EBSS) starvation. Replacement of complete medium with EBSS was used to trigger canonical autophagy. BAG3 expression was measured using real-time RT-PCR and Western blot. Autophagy was monitored using LC3-II transition and p62/SQSTM1 accumulation by Western blot, as well as punctate distribution of LC3 by immunofluorescence staining. Cell growth and apoptotic cell death was investigated using real-time cell analyzer and flowcytometry, respectively. BAG3 expression was potently reduced by EBSS starvation. Forced expression of BAG3 suppressed autophagy and promoted apoptotic cell death of thyroid cancer cells elicited by starvation. In addition, in the presence of autophagy inhibitor, the enhancing effect of BAG3 on apoptotic cell death was attenuated. These results suggest that BAG3 promotes apoptotic cell death in starved thyroid cancer cells, at least in part by autophagy attenuation.

  1. The Politics of Starvation Deaths in West Bengal

    DEFF Research Database (Denmark)

    Rubin, Olivier

    2011-01-01

    This article examines the local socio-political causes behind a sudden wave of starvation deaths that swept across the West Bengali village of Amlashol during the summer of 2004. Following the new paradigm of famine analysis where focus is placed on political failures, the article addresses three...... of chronic food insecurity into an acute hunger crisis, which was not mitigated by effective public policies at the local level due to extensive political patronage and a politicisation of the bureaucracy. Amlashol suffered disproportionally from this due to the village’s affiliation with a weak...

  2. Phosphate starvation triggers production and secretion of an extracellular lipoprotein in Caulobacter crescentus.

    Directory of Open Access Journals (Sweden)

    Sophie Le Blastier

    Full Text Available Life in oligotrophic environments necessitates quick adaptive responses to a sudden lack of nutrients. Secretion of specific degradative enzymes into the extracellular medium is a means to mobilize the required nutrient from nearby sources. The aquatic bacterium Caulobacter crescentus must often face changes in its environment such as phosphate limitation. Evidence reported in this paper indicates that under phosphate starvation, C. crescentus produces a membrane surface-anchored lipoprotein named ElpS subsequently released into the extracellular medium. A complete set of 12 genes encoding a type II secretion system (T2SS is located adjacent to the elpS locus in the C. crescentus genome. Deletion of this T2SS impairs release of ElpS in the environment, which surprisingly remains present at the cell surface, indicating that the T2SS is not involved in the translocation of ElpS to the outer membrane but rather in its release. Accordingly, treatment with protease inhibitors prevents release of ElpS in the extracellular medium suggesting that ElpS secretion relies on a T2SS-secreted protease. Finally, secretion of ElpS is associated with an increase in alkaline phosphatase activity in culture supernatants, suggesting a role of the secreted protein in inorganic phosphate mobilization. In conclusion, we have shown that upon phosphate starvation, C. crescentus produces an outer membrane bound lipoprotein, ElpS, which is further cleaved and released in the extracellular medium in a T2SS-dependent manner. Our data suggest that ElpS is associated with an alkaline phosphatase activity, thereby allowing the bacterium to gather inorganic phosphates from a poor environment.

  3. Direct Sulfation of Limestone

    DEFF Research Database (Denmark)

    Hu, Guilin; Dam-Johansen, Kim; Wedel, Stig

    2007-01-01

    The direct sulfation of limestone was studied in a laboratory fixed-bed reactor. It is found that the direct sulfation of limestone involves nucleation and crystal grain growth of the solid product (anhydrite). At 823 K and at low-conversions (less than about 0.5 %), the influences of SO2, O-2...... and CO2 on the direct sulfation of limestone corresponds to apparent reaction orders of about 0.2, 0.2 and -0.5, respectively. Water is observed to promote the sulfation reaction and increase the apparent reaction orders of SO2 and O-2. The influence of O-2 at high O-2 concentrations (> about 15...... %) becomes negligible. In the temperature interval from 723 K to 973 K, an apparent activation energy of about 104 kJ/mol is observed for the direct sulfation of limestone. At low temperatures and low conversions, the sulfation process is most likely under mixed control by chemical reaction and solid...

  4. Simulated responses of terrestrial aridity to black carbon and sulfate aerosols

    Science.gov (United States)

    Lin, L.; Gettelman, A.; Xu, Y.; Fu, Q.

    2016-01-01

    Aridity index (AI), defined as the ratio of precipitation to potential evapotranspiration (PET), is a measure of the dryness of terrestrial climate. Global climate models generally project future decreases of AI (drying) associated with global warming scenarios driven by increasing greenhouse gas and declining aerosols. Given their different effects in the climate system, scattering and absorbing aerosols may affect AI differently. Here we explore the terrestrial aridity responses to anthropogenic black carbon (BC) and sulfate (SO4) aerosols with Community Earth System Model simulations. Positive BC radiative forcing decreases precipitation averaged over global land at a rate of 0.9%/°C of global mean surface temperature increase (moderate drying), while BC radiative forcing increases PET by 1.0%/°C (also drying). BC leads to a global decrease of 1.9%/°C in AI (drying). SO4 forcing is negative and causes precipitation a decrease at a rate of 6.7%/°C cooling (strong drying). PET also decreases in response to SO4 aerosol cooling by 6.3%/°C cooling (contributing to moistening). Thus, SO4 cooling leads to a small decrease in AI (drying) by 0.4%/°C cooling. Despite the opposite effects on global mean temperature, BC and SO4 both contribute to the twentieth century drying (AI decrease). Sensitivity test indicates that surface temperature and surface available energy changes dominate BC- and SO4-induced PET changes.

  5. Monitoring protein turnover during phosphate starvation-dependent autophagic degradation using a photoconvertible fluorescent protein aggregate in tobacco BY-2 cells.

    Science.gov (United States)

    Tasaki, Maiko; Asatsuma, Satoru; Matsuoka, Ken

    2014-01-01

    We have developed a system for quantitative monitoring of autophagic degradation in transformed tobacco BY-2 cells using an aggregate-prone protein comprised of cytochrome b5 (Cyt b5) and a tetrameric red fluorescent protein (RFP). Unfortunately, this system is of limited use for monitoring the kinetics of autophagic degradation because the proteins synthesized before and after induction of autophagy cannot be distinguished. To overcome this problem, we developed a system using kikume green-red (KikGR), a photoconvertible and tetrameric fluorescent protein that changes its fluorescence from green to red upon irradiation with purple light. Using the fusion protein of Cyt b5 and KikGR together with a method for the bulk conversion of KikGR, which we had previously used to convert the Golgi-localized monomeric KikGR fusion protein, we were able to monitor both the growth and de novo formation of aggregates. Using this system, we found that tobacco cells do not cease protein synthesis under conditions of phosphate (Pi)-starvation. Induction of autophagy under Pi-starvation, but not under sugar- or nitrogen-starvation, was specifically inhibited by phosphite, which is an analog of Pi with a different oxidation number. Therefore, the mechanism by which BY-2 cells can sense Pi-starvation and induce autophagy does not involve sensing a general decrease in energy supply and a specific Pi sensor might be involved in the induction of autophagy under Pi-starvation.

  6. Measurement of chemical leaching potential of sulfate from landfill disposed sulfate containing wastes.

    Science.gov (United States)

    Sun, Wenjie; Barlaz, Morton A

    2015-02-01

    A number of sulfate-containing wastes are disposed in municipal solid wastes (MSW) landfills including residues from coal, wood, and MSW combustion, and construction and demolition (C&D) waste. Under anaerobic conditions that dominate landfills, the sulfate can be reduced to hydrogen sulfide which is problematic for several reasons including its low odor threshold, toxicity, and corrosive nature. The overall objective of this study was to evaluate existing protocols for the quantification of total leachable sulfate from solid samples and to compare their effectiveness and efficiency with a new protocol described in this study. Methods compared include two existing acid extraction protocols commonly used in the U.S., a pH neutral protocol that requires multiple changes of the leaching solution, and a new acid extraction method. The new acid extraction method was shown to be simple and effective to measure the leaching potential of sulfate from a range of landfill disposed sulfate-containing wastes. However, the acid extraction methods do not distinguish between sulfate and other forms of sulfur and are thus most useful when sulfate is the only form of sulfur present. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Genome-wide analysis of autophagy-associated genes in foxtail millet (Setaria italica L.) and characterization of the function of SiATG8a in conferring tolerance to nitrogen starvation in rice.

    Science.gov (United States)

    Li, Weiwei; Chen, Ming; Wang, Erhui; Hu, Liqin; Hawkesford, Malcolm J; Zhong, Li; Chen, Zhu; Xu, Zhaoshi; Li, Liancheng; Zhou, Yongbin; Guo, Changhong; Ma, Youzhi

    2016-10-12

    Autophagy is a cellular degradation process that is highly evolutionarily-conserved in yeast, plants, and animals. In plants, autophagy plays important roles in regulating intracellular degradation and recycling of amino acids in response to nutrient starvation, senescence, and other environmental stresses. Foxtail millet (Setaria italica) has strong resistance to stresses and has been proposed as an ideal material for use in the study of the physiological mechanisms of abiotic stress tolerance in plants. Although the genome sequence of foxtail millet (Setaria italica) is available, the characteristics and functions of abiotic stress-related genes remain largely unknown for this species. A total of 37 putative ATG (autophagy-associated genes) genes in the foxtail millet genome were identified. Gene duplication analysis revealed that both segmental and tandem duplication events have played significant roles in the expansion of the ATG gene family in foxtail millet. Comparative synteny mapping between the genomes of foxtail millet and rice suggested that the ATG genes in both species have common ancestors, as their ATG genes were primarily located in similar syntenic regions. Gene expression analysis revealed the induced expression of 31 SiATG genes by one or more phytohormone treatments, 26 SiATG genes by drought, salt and cold, 24 SiATG genes by darkness and 25 SiATG genes by nitrogen starvation. Results of qRT-PCR showing that among 37 SiATG genes, the expression level of SiATG8a was the highest after nitrogen starvation treatment 24 h, suggesting its potential role in tolerance to nutrient starvation. Moreover, the heterologous expression of SiATG8a in rice improved nitrogen starvation tolerance. Compared to wild type rice, the transgenic rice performed better and had higher aboveground total nitrogen content when the plants were grown under nitrogen starvation conditions. Our results deepen understanding about the characteristics and functions of ATG genes in

  8. The corticotropin-releasing factor-like diuretic hormone 44 (DH44) and kinin neuropeptides modulate desiccation and starvation tolerance in Drosophila melanogaster.

    Science.gov (United States)

    Cannell, Elizabeth; Dornan, Anthony J; Halberg, Kenneth A; Terhzaz, Selim; Dow, Julian A T; Davies, Shireen-A

    2016-06-01

    Malpighian tubules are critical organs for epithelial fluid transport and stress tolerance in insects, and are under neuroendocrine control by multiple neuropeptides secreted by identified neurons. Here, we demonstrate roles for CRF-like diuretic hormone 44 (DH44) and Drosophila melanogaster kinin (Drome-kinin, DK) in desiccation and starvation tolerance. Gene expression and labelled DH44 ligand binding data, as well as highly selective knockdowns and/or neuronal ablations of DH44 in neurons of the pars intercerebralis and DH44 receptor (DH44-R2) in Malpighian tubule principal cells, indicate that suppression of DH44 signalling improves desiccation tolerance of the intact fly. Drome-kinin receptor, encoded by the leucokinin receptor gene, LKR, is expressed in DH44 neurons as well as in stellate cells of the Malpighian tubules. LKR knockdown in DH44-expressing neurons reduces Malpighian tubule-specific LKR, suggesting interactions between DH44 and LK signalling pathways. Finally, although a role for DK in desiccation tolerance was not defined, we demonstrate a novel role for Malpighian tubule cell-specific LKR in starvation tolerance. Starvation increases gene expression of epithelial LKR. Also, Malpighian tubule stellate cell-specific knockdown of LKR significantly reduced starvation tolerance, demonstrating a role for neuropeptide signalling during starvation stress. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Prognostic significance of highly sulfated chondroitin sulfates in ovarian cancer defined by the single chain antibody GD3A11.

    Science.gov (United States)

    van der Steen, Sophieke C H A; van Tilborg, Angela A G; Vallen, Myrtille J E; Bulten, Johan; van Kuppevelt, Toin H; Massuger, Leon F A G

    2016-03-01

    The extracellular matrix (ECM) of ovarian cancer may provide a number of potential biomarkers. Chondroitin sulfate (CS), a class of sulfated polysaccharides, is abundantly present in the ECM of ovarian cancer. Structural alterations of CS chains (i.e. sulfation pattern) have been demonstrated to play a role in cancer development and progression. In this study we investigate the potential of highly sulfated CS as a biomarker in ovarian cancer using the single chain antibody GD3A11 selected by the phage display technology. The specificity of the antibody was determined by an indirect ELISA. GD3A11 epitope expression was assessed by immunohistochemistry in healthy organs, benign and malignant ovarian tumors (N=359) and correlated to clinical parameters. The CHST15 gene, responsible for the biosynthesis of highly sulfated CS was evaluated for mutation and methylation status. The GD3A11 epitope was minimally expressed in normal organs. Intense expression was observed in the ECM of different ovarian cancer subtypes, in contrast to benign ovarian tumors. Expression was independent of tumor grade, FIGO stage, and the use chemotherapy. For the aggressive ovarian cancer phenotype, intense expression was identified as an independent predictor for poor prognosis. CHST15 gene analysis showed no mutations nor an altered methylation status. Specific highly sulfated CS motifs expressed in the tumoral ECM hold biomarker potential in ovarian cancer patients. These matrix motifs constitute a novel class of biomarkers with prognostic significance and may be instrumental for innovative diagnostic and therapeutic applications (e.g. targeted therapy) in management of ovarian cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Inhibition of synthesis of heparan sulfate by selenate: Possible dependence on sulfation for chain polymerization

    International Nuclear Information System (INIS)

    Dietrich, C.P.; Nader, H.B.; Buonassisi, V.; Colburn, P.

    1988-01-01

    Selenate, a sulfation inhibitor, blocks the synthesis of heparan sulfate and chondroitin sulfate by cultured endothelial cells. In contrast, selenate does not affect the production of hyaluronic acid, a nonsulfated glycosaminoglycan. No differences in molecular weight, [ 3 H]glucosamine/[ 35 S]sulfuric acid ratios, or disaccharide composition were observed when the heparan sulfate synthesized by selenate-treated cells was compared with that of control cells. The absence of undersulfated chains in preparations from cultures exposed to selenate supports the concept that, in the intact cell, the polymerization of heparan sulfate might be dependent on the sulfation of the saccharide units added to the growing glycosaminoglycan chain

  11. Growth and sedimentation of fine particles produced in aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation

    International Nuclear Information System (INIS)

    Hatada, Motoyoshi; Jonah, C.D.

    1994-10-01

    It is known that palladium and palladium-silver fine particles were formed from deaerated aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation. Changes in particle size and with amount of particles in the solution with time during and after irradiation were studied using dynamic light scattering technique and UV spectrophotometer. The particles formed from palladium sulfate solution are found to be water-filled bulky particles of diameter of 200 nm, which grow by mutual coagulation even after irradiation was terminated. Average density depends on concentration of palladium ion in the solution and dose, and the lowest density was about 2 g/cm 3 for particles of 200 nm obtained from 0.06 mM solution by 2.4 kGy irradiation. The average density of the particles obtained from palladium sulfate-silver sulfate solutions was smaller than those obtained for the corresponding palladium sulfate solutions. Supersonic agitation destroyed coagulated precipitates to form fine particles, but did not form clusters of a few atoms. (author)

  12. High rates of sulfate reduction in a low-sulfate hot spring microbial mat are driven by a low level of diversity of sulfate-respiring microorganisms

    DEFF Research Database (Denmark)

    Dillon, Jesse G; Fishbain, Susan; Miller, Scott R

    2007-01-01

    The importance of sulfate respiration in the microbial mat found in the low-sulfate thermal outflow of Mushroom Spring in Yellowstone National Park was evaluated using a combination of molecular, microelectrode, and radiotracer studies. Despite very low sulfate concentrations, this mat community...... was shown to sustain a highly active sulfur cycle. The highest rates of sulfate respiration were measured close to the surface of the mat late in the day when photosynthetic oxygen production ceased and were associated with a Thermodesulfovibrio-like population. Reduced activity at greater depths...... was correlated with novel populations of sulfate-reducing microorganisms, unrelated to characterized species, and most likely due to both sulfate and carbon limitation....

  13. Phloem small RNAs, nutrient stress responses, and systemic mobility

    Directory of Open Access Journals (Sweden)

    Kehr Julia

    2010-04-01

    Full Text Available Abstract Background Nutrient availabilities and needs have to be tightly coordinated between organs to ensure a balance between uptake and consumption for metabolism, growth, and defense reactions. Since plants often have to grow in environments with sub-optimal nutrient availability, a fine tuning is vital. To achieve this, information has to flow cell-to-cell and over long-distance via xylem and phloem. Recently, specific miRNAs emerged as a new type of regulating molecules during stress and nutrient deficiency responses, and miR399 was suggested to be a phloem-mobile long-distance signal involved in the phosphate starvation response. Results We used miRNA microarrays containing all known plant miRNAs and a set of unknown small (s RNAs earlier cloned from Brassica phloem sap 1, to comprehensively analyze the phloem response to nutrient deficiency by removing sulfate, copper or iron, respectively, from the growth medium. We show that phloem sap contains a specific set of sRNAs that is distinct from leaves and roots, and that the phloem also responds specifically to stress. Upon S and Cu deficiencies phloem sap reacts with an increase of the same miRNAs that were earlier characterized in other tissues, while no clear positive response to -Fe was observed. However, -Fe led to a reduction of Cu- and P-responsive miRNAs. We further demonstrate that under nutrient starvation miR399 and miR395 can be translocated through graft unions from wild type scions to rootstocks of the miRNA processing hen1-1 mutant. In contrast, miR171 was not transported. Translocation of miR395 led to a down-regulation of one of its targets in rootstocks, suggesting that this transport is of functional relevance, and that miR395, in addition to the well characterized miR399, could potentially act as a long-distance information transmitter. Conclusions Phloem sap contains a specific set of sRNAs, of which some specifically accumulate in response to nutrient deprivation. From

  14. Sulfation of corrosive alkali chlorides by ammonium sulfate in a biomass fired CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Brostroem, Markus; Backman, Rainer; Nordin, Anders [Energy Technology and Thermal Process Chemistry, Umeaa University, SE-901 87 Umeaa (Sweden); Kassman, Haakan [Vattenfall Power Consultant AB, Box 1046, SE-611 29 Nykoeping (Sweden); Helgesson, Anna; Berg, Magnus; Andersson, Christer [Vattenfall Research and Development AB, SE-814 26 Aelvkarleby (Sweden)

    2007-12-15

    Biomass and waste derived fuels contain relatively high amounts of alkali and chlorine, but contain very little sulfur. Combustion of such fuels can result in increased deposit formation and superheater corrosion. These problems can be reduced by using a sulfur containing additive, such as ammonium sulfate, which reacts with the alkali chlorides and forms less corrosive sulfates. Ammonium sulfate injection together with a so-called in situ alkali chloride monitor (IACM) is patented and known as ''ChlorOut''. IACM measures the concentrations of alkali chlorides (mainly KCl in biomass combustion) at superheater temperatures. Tests with and without spraying ammonium sulfate into the flue gases have been performed in a 96MW{sub th}/25MW{sub e} circulating fluidized bed (CFB) boiler. The boiler was fired mainly with bark and a chlorine containing waste. KCl concentration was reduced from more than 15 ppm to approximately 2 ppm during injection of ammonium sulfate. Corrosion probe measurements indicated that both deposit formation and material loss due to corrosion were decreased using the additive. Analysis of the deposits showed significantly higher concentration of sulfur and almost no chlorine in the case with ammonium sulfate. Results from impactor measurements supported that KCl was sulfated to potassium sulfate by the additive. (author)

  15. Synthesis of heparan sulfate with cyclophilin B-binding properties is determined by cell type-specific expression of sulfotransferases.

    NARCIS (Netherlands)

    Deligny, A.; Denys, A.; Marcant, A.; Melchior, A.; Mazurier, J.; Kuppevelt, A.H.M.S.M. van; Allain, F.

    2010-01-01

    Cyclophilin B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsible for N-sulfation, which

  16. Nondiabetic ketoacidosis in a pregnant woman due to acute starvation with concomitant influenza A (H1N1) and respiratory failure.

    Science.gov (United States)

    Skalley, G; Rodríguez-Villar, S

    2018-02-28

    Threatening refractory metabolic acidosis due to short-term starvation nondiabetic ketoacidosis is rarely reported. Severe ketoacidosis due to starvation itself is a rare occurrence, and more so in pregnancy with a concomitant stressful clinical situation. This case report presents a nondiabetic woman admitted in intensive care for respiratory failure type 1 during the third trimester of pregnancy with a severe metabolic acidosis refractory to medical treatment. We diagnosed the patient with acute starvation ketoacidosis based on her history and the absence of other causes of high anion gap metabolic acidosis after doing a rigorous analysis of her acid-base disorder. Crown Copyright © 2018. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Chondroitin sulfate/dermatan sulfate sulfatases from mammals and bacteria.

    Science.gov (United States)

    Wang, Shumin; Sugahara, Kazuyuki; Li, Fuchuan

    2016-12-01

    Sulfatases that specifically catalyze the hydrolysis of the sulfate groups on chondroitin sulfate (CS)/dermatan sulfate (DS) poly- and oligosaccharides belong to the formylglycine-dependent family of sulfatases and have been widely found in various mammalian and bacterial organisms. However, only a few types of CS/DS sulfatase have been identified so far. Recently, several novel CS/DS sulfatases have been cloned and characterized. Advanced studies have provided significant insight into the biological function and mechanism of action of CS/DS sulfatases. Moreover, further studies will provide powerful tools for structural and functional studies of CS/DS as well as related applications. This article reviews the recent progress in CS/DS sulfatase research and is expected to initiate further research in this field.

  18. Novel processes for anaerobic sulfate production from elemental sulfur by sulfate-reducing bacteria

    Science.gov (United States)

    Lovley, D.R.; Phillips, E.J.P.

    1994-01-01

    Sulfate reducers and related organisms which had previously been found to reduce Fe(III) with H2 or organic electron donors oxidized S0 to sulfate when Mn(IV) was provided as an electron acceptor. Organisms catalyzing this reaction in washed cell suspensions included Desulfovibrio desulfuricans, Desulfomicrobium baculatum. Desulfobacterium autotrophicum, Desulfuromonas acetoxidans, and Geobacter metallireducens. These organisms produced little or no sulfate from S0 with Fe(III) as a potential electron acceptor or in the absence of an electron acceptor. In detailed studies with Desulfovibrio desulfuricans, the stoichiometry of sulfate and Mn(II) production was consistent with the reaction S0 + 3 MnO2 + 4H+ ???SO42- + 3Mn(II) + 2H2O. None of the organisms evaluated could be grown with S0 as the sole electron donor and Mn(IV) as the electron acceptor. In contrast to the other sulfate reducers evaluated, Desulfobulbus propionicus produced sulfate from S0 in the absence of an electron acceptor and Fe(III) oxide stimulated sulfate production. Sulfide also accumulated in the absence of Mn(IV) or Fe(III). The stoichiometry of sulfate and sulfide production indicated that Desulfobulbus propionicus disproportionates S0 as follows: 4S0 + 4H2O???SO42- + 3HS- + 5 H+. Growth of Desulfobulbus propionicus with S0 as the electron donor and Fe(III) as a sulfide sink and/or electron acceptor was very slow. The S0 oxidation coupled to Mn(IV) reduction described here provides a potential explanation for the Mn(IV)-dependent sulfate production that previous studies have observed in anoxic marine sediments. Desulfobulbus propionicus is the first example of a pure culture known to disproportionate S0.

  19. Heparan sulfate-chondroitin sulfate hybrid proteoglycan of the cell surface and basement membrane of mouse mammary epithelial cells

    International Nuclear Information System (INIS)

    David, G.; Van den Berghe, H.

    1985-01-01

    Chondroitin sulfate represents approximately 15% of the 35 SO 4 -labeled glycosaminoglycans carried by the proteoglycans of the cell surface and of the basolateral secretions of normal mouse mammary epithelial cells in culture. Evidence is provided that these chondroitin sulfate-carrying proteoglycans are hybrid proteoglycans, carrying both chondroitin sulfate and heparan sulfate chains. Complete N-desulfation but limited O-desulfation, by treatment with dimethyl sulfoxide, of the proteoglycans decreased the anionic charge of the chondroitin sulfate-carrying proteoglycans to a greater extent than it decreased the charge of their constituent chondroitin sulfate chains. Partial depolymerization of the heparan sulfate residues of the proteoglycans with nitrous acid or with heparin lyase also reduced the effective molecular radius of the chondroitin sulfate-carrying proteoglycans. The effect of heparin lyase on the chondroitin sulfate-carrying proteoglycans was prevented by treating the proteoglycan fractions with dimethyl sulfoxide, while the effect of nitrous acid on the dimethyl sulfoxide-treated proteoglycans was prevented by acetylation. This occurrence of heparan sulfate-chondroitin sulfate hybrid proteoglycans suggests that the substitution of core proteins by heparan sulfate or chondroitin sulfate chains may not solely be determined by the specific routing of these proteins through distinct chondroitin sulfate and heparan sulfate synthesizing mechanisms. Moreover, regional and temporal changes in pericellular glycosaminoglycan compositions might be due to variable postsynthetic modification of a single gene product

  20. Everyday life in wartime Arkhangelsk: The problem of starvation and death during the Second World War (1939–1945)

    OpenAIRE

    Khatanzeiskaya, Elizaveta

    2015-01-01

    The article «Everyday Life in Wartime Arkhangelsk: The Problem of Starvation and Death during the Second World War (1939–1945)» is based on primary sources: interviews with eyewitnesses, memoirs, materials of press, diaries and archival documents. During the Second World War more than 40 thousand civilians died in Arkhangelsk (one fourth of its prewar population) because of starvation. This paper is an attempt to explain this phenomenon. 

  1. Response And Recovery Of Sulfate-Reducing Biochemical Reactors From Aerobic Stress Events

    Science.gov (United States)

    Microbially-mediated treatment of mining-influenced water (MIW) through the implementation of sulfate-reducing biochemical reactors (BCRs) is an attractive option for passive, in situ remediation with low operating costs and reduced maintenance requirements. However, BCRs can be...

  2. Sulfates on Mars: A systematic Raman spectroscopic study of hydration states of magnesium sulfates

    Science.gov (United States)

    Wang, A.; Freeman, J.J.; Jolliff, B.L.; Chou, I.-Ming

    2006-01-01

    The martian orbital and landed surface missions, OMEGA on Mar Express and the two Mars Explorations Rovers, respectively, have yielded evidence pointing to the presence of magnesium sulfates on the martian surface. In situ identification of the hydration states of magnesium sulfates, as well as the hydration states of other Ca- and Fe- sulfates, will be crucial in future landed missions on Mars in order to advance our knowledge of the hydrologic history of Mars as well as the potential for hosting life on Mars. Raman spectroscopy is a technique well-suited for landed missions on the martian surface. In this paper, we report a systematic study of the Raman spectra of the hydrates of magnesium sulfate. Characteristic and distinct Raman spectral patterns were observed for each of the 11 distinct hydrates of magnesium sulfates, crystalline and non-crystalline. The unique Raman spectral features along with the general tendency of the shift of the position of the sulfate ??1 band towards higher wavenumbers with a decrease in the degree of hydration allow in situ identification of these hydrated magnesium sulfates from the raw Raman spectra of mixtures. Using these Raman spectral features, we have started the study of the stability field of hydrated magnesium sulfates and the pathways of their transformations at various temperature and relative humidity conditions. In particular we report on the Raman spectrum of an amorphous hydrate of magnesium sulfate (MgSO4??2H2O) that may have specific relevance for the martian surface. ?? 2006 Elsevier Inc. All rights reserved.

  3. Sulfur isotopic and proteomic profiles of sulfate reducers grown under differential steady-states

    Science.gov (United States)

    Leavitt, W.; Venceslau, S.; Waldbauer, J.; Smith, D. A.; Boidi, F. J.; Bradley, A. S.

    2016-12-01

    Microbial sulfate reducers (MSR) drive the Earth's biogeochemical sulfur cycle. At the heart of this energy metabolism is a cascade of redox transformations coupling organic carbon and/or hydrogen oxidation to the dissimilatory reduction of sulfate to sulfide. The product sulfide is depleted in the heavier isotopes of sulfur, relative to the reactant sulfate, consistent with a normal kinetic isotope effect. However, the magnitude of the net fractionation during MSR can range over a range of 70 permil, consistent with a multi-step set of reactions. This range in MSR fractionation has been shown to mainly depend on: i) the cell-specific sulfate reduction rate (csSRR), and ii) the ambient sulfate concentration. However, the fractionation under identical conditions differs among strains (Bradley et al. 2016. Geobio), and so must also be mediated by strain-specific processes, such as the nature and quantity of individual proteins involved in sulfate reduction, electron transport, and growth. In recent work we have examined the influence of electron donor, electron acceptor, and co-limitation under controlled steady-state culture conditions in order better inform models of MSR isotope fractionation, and the physiological and isotopic response to differential environmental forcings (e.g. Leavitt et al. (2013) PNAS). Recent models of the fractionation response to MSR rate (c.f. Bradley 2016; Wing & Halevy, 2016) make specific predictions for the responses of the cellular metabolome and proteome. Here we compare the steady-state S-isotopic fractionation and proteome of `fast' versus `slow' grown D. vulgaris, using replicate chemostats under electron donor limitation. We observe clear and statistically robust changes in some key central MSR and C-metabolism enzymes, though a host of the critical energy-transfer enzymes show no statistically discernable change. We discuss these results in light of recent theoretical advances and their relevance to modern and ancient

  4. Neomercazole protection against radiation-induced changes in bioamines and testicular metabolism of rats during starvation stress

    International Nuclear Information System (INIS)

    Hasan, S.S.; Kushwaha, A.K.S.

    1987-01-01

    Effect of X rays was studied on normally fed and starved rats vis-a-vis neomercazole, a sulfur containing carbimazone as a chemical radioprotector. Levels of 5-hydroxyindoleacetic acid and vinylmandelic acid which were found rising following exposure to X-rays, were significantly curtailed by the treatment with radioprotector in the protected-cum-irradiated rats. Administration of neomercazole offered protection to the testes against radiation injury by increasing alkaline phophatase and cholesterol contents in the testes of drug-treated-cum-irradiated animals. Pretreatment of neomercazole reduced the rate of mortality in the starvation-cum-irradiated animals as compared to the nontreated starvation-cum-irradiated animals. (author)

  5. Analysis of tyrosine-O-sulfation

    DEFF Research Database (Denmark)

    Bundgaard, J.R.; Sen, J.W.; Johnsen, A.H.

    2008-01-01

    Tyrosine O-sulfation was first described about 50 years ago as a post-translational modification of fibrinogen. In the following 30 years it was considered to be a rare modification affecting only a few proteins and peptides. However, in the beginning of the 1980s tyrosine (Tyr) sulfation was shown...... to be a common modification and since then an increasing number of proteins have been identified as sulfated. The target proteins belong to the classes of secretory, plasma membrane, and lysosomal proteins, which reflects the intracellular localization of the enzymes catalyzing Tyr sulfation, the tyrosylprotein...... sulfotransferases (TPSTs).Traditionally, Tyr sulfation has been analyzed by incorporation of radiolabeled sulfate into target cells followed by purification of the target protein. Subsequently, the protein is degraded enzymatically or by alkaline hydrolysis followed by thin-layer electrophoresis to demonstrate...

  6. Varying response of the concentration and content of soybean seed mineral elements, carbohydrates, organic acids, amino acids, protein, and oil to phosphorus starvation and CO2 enrichment

    Science.gov (United States)

    A detailed investigation of the concentration (g-1 seed weight) and content (g plant-1) of seed mineral elements and metabolic profile under phosphorus (P) starvation at ambient (aCO2) and elevated carbon dioxide (eCO2) in soybean is limited. Soybean plants were grown in a controlled environment at ...

  7. Immunohistochemical localization of chondroitin sulfate, chondroitin sulfate proteoglycan, heparan sulfate proteoglycan, entactin, and laminin in basement membranes of postnatal developing and adult rat lungs

    DEFF Research Database (Denmark)

    Sannes, P L; Burch, K K; Khosla, J

    1993-01-01

    Histologic preparations of lungs from 1-, 5-, 10-, 18-, and 25-day-old postnatal and adult rats were examined immunohistochemically with antibodies specific against chondroitin sulfate (CS), basement membrane chondroitin sulfate proteoglycan (BM-CSPG), heparan sulfate proteoglycan (HSPG), entactin...

  8. Real-time metabolome profiling of the metabolic switch between starvation and growth.

    Science.gov (United States)

    Link, Hannes; Fuhrer, Tobias; Gerosa, Luca; Zamboni, Nicola; Sauer, Uwe

    2015-11-01

    Metabolic systems are often the first networks to respond to environmental changes, and the ability to monitor metabolite dynamics is key for understanding these cellular responses. Because monitoring metabolome changes is experimentally tedious and demanding, dynamic data on time scales from seconds to hours are scarce. Here we describe real-time metabolome profiling by direct injection of living bacteria, yeast or mammalian cells into a high-resolution mass spectrometer, which enables automated monitoring of about 300 compounds in 15-30-s cycles over several hours. We observed accumulation of energetically costly biomass metabolites in Escherichia coli in carbon starvation-induced stationary phase, as well as the rapid use of these metabolites upon growth resumption. By combining real-time metabolome profiling with modeling and inhibitor experiments, we obtained evidence for switch-like feedback inhibition in amino acid biosynthesis and for control of substrate availability through the preferential use of the metabolically cheaper one-step salvaging pathway over costly ten-step de novo purine biosynthesis during growth resumption.

  9. Nitrogen starvation of cyanobacteria results in the production of β-N-methylamino-L-alanine.

    Science.gov (United States)

    Downing, S; Banack, S A; Metcalf, J S; Cox, P A; Downing, T G

    2011-08-01

    β-N-Methylamino-L-alanine, an unusual amino acid implicated in neurodegenerative disease, has been detected in cultures of nearly all genera of environmentally ubiquitous cyanobacteria tested. The compound is present within cyanobacterial cells in free and protein-associated forms, with large variations occurring in the concentration of these pools between species as well as within single strains. With a lack of knowledge and supporting data on the regulation of BMAA production and the role of this compound in cyanobacteria, the association between BMAA and cyanobacteria is still subject to debate. In this study we investigated the biosynthesis of BMAA in axenic non-diazotrophic cyanobacterial cultures using the stable isotope ¹⁵N. Nitrogen starvation of nutritionally replete cells resulted in an increase in free cellular ¹⁵N BMAA suggesting that BMAA may be the result of catabolism to provide nitrogen or that BMAA is synthesised to serve a functional role in the cell in response to nitrogen deprivation. The addition of NO₃⁻ and NH₄⁺ to the culture medium following starvation resulted in a decrease of free cellular BMAA without a corresponding increase in the protein-associated fraction. The use of ammonia as a nitrogen source resulted in a more rapid reduction of BMAA when compared to nitrate. This study provides the first data regarding the regulation of intracellular BMAA concentrations in cyanobacteria with results conclusively showing the production of ¹⁵N BMAA by an axenic cyanobacterial culture. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. A multi-pronged investigation into the effect of glucose starvation and culture duration on fed-batch CHO cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    to the interplay between the dilution effect associated with change in specific productivity of mAbs and the changed nucleotide sugar metabolism. Herein, we also show and discuss that increased cell culture duration negatively affect the maturation of glycans. In addition, comparative proteomics analysis of cells......In this study, omics-based analysis tools were used to explore the effect of glucose starvation and culture duration on monoclonal antibody (mAb) production in fed-batch CHO cell culture to gain better insight into how these parameters can be controlled to ensure optimal mAb productivity...... and quality. Titer and N-glycosylation of mAbs, as well as proteomic signature and metabolic status of the production cells in the culture were assessed. We found that the impact of glucose starvation on the titer and N-glycosylation of mAbs was dependent on the degree of starvation during early stationary...

  11. Tomato strigolactones are derived from carotenoids and their biosynthesis is promoted by phosphate starvation

    NARCIS (Netherlands)

    Lopez Raez, J.A.; Charnikhova, T.; Gomez-Roldan, M.V.; Matusova, R.; Kohlen, W.; Vos, de C.H.; Verstappen, F.W.A.; Puech-Pages, V.; Becard, G.; Mulder, P.P.J.; Bouwmeester, H.J.

    2008-01-01

    Strigolactones are rhizosphere signalling compounds that mediate host location in arbuscular mycorrhizal (AM) fungi and parasitic plants. Here, the regulation of the biosynthesis of strigolactones is studied in tomato (Solanum lycopersicum). Strigolactone production under phosphate starvation, in

  12. Macrophage secretory products selectively stimulate dermatan sulfate proteoglycan production in cultured arterial smooth muscle cells

    International Nuclear Information System (INIS)

    Edwards, I.J.; Wagner, W.D.; Owens, R.T.

    1990-01-01

    Arterial dermatan sulfate proteoglycan has been shown to increase with atherosclerosis progression, but factors responsible for this increase are unknown. To test the hypothesis that smooth muscle cell proteoglycan synthesis may be modified by macrophage products, pigeon arterial smooth muscle cells were exposed to the media of either cholesteryl ester-loaded pigeon peritoneal macrophages or a macrophage cell line P388D1. Proteoglycans radiolabeled with [35S]sulfate and [3H]serine were isolated from culture media and smooth muscle cells and purified following precipitation with 1-hexadecylpyridinium chloride and chromatography. Increasing concentrations of macrophage-conditioned media were associated with a dose-response increase in [35S]sulfate incorporation into secreted proteoglycans, but there was no change in cell-associated proteoglycans. Incorporation of [3H]serine into total proteoglycan core proteins was not significantly different (5.2 X 10(5) dpm and 5.5 X 10(5) disintegrations per minute (dpm) in control and conditioned media-treated cultures, respectively), but selective effects were observed on individual proteoglycan types. Twofold increases in dermatan sulfate proteoglycan and limited degradation of chondroitin sulfate proteoglycan were apparent based on core proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Immunoinhibition studies indicated that interleukin-1 was involved in the modulation of proteoglycan synthesis by macrophage-conditioned media. These data provide support for the role of macrophages in alteration of the matrix proteoglycans synthesized by smooth muscle cells and provide a mechanism to account for the reported increased dermatan sulfate/chondroitin sulfate ratios in the developing atherosclerotic lesion

  13. SU-E-I-92: Is Photon Starvation Preventing Metal Artifact Reduction Algorithm From Working in KVCT?

    Energy Technology Data Exchange (ETDEWEB)

    Paudel, M [University of Alberta, Cross Cancer Institute, Edmonton, AB (Canada); currently at University of Toronto, Sunnybrook Health Sciences Center, Toronto, ON (Canada); MacKenzie, M; Fallone, B; Rathee, S [University of Alberta, Cross Cancer Institute, Edmonton, AB (Canada)

    2014-06-01

    Purpose: High density/high atomic number metallic objects create shading and streaking metal artifacts in the CT image that can cause inaccurate delineation of anatomical structures or inaccurate radiation dose calculation. A modified iterative maximum-likelihood polychromatic algorithm for CT (mIMPACT) that models the energy response of detectors, photon interaction processes and beam polychromaticity has successfully reduced metal artifacts in MVCT. Our extension of mIMPACT in kVCT did not significantly reduce metal artifacts for high density metal like steel. We hypothesize that photon starvation may result in the measured data in a commercial kVCT imaging beam. Methods: We measured attenuation of a range of steel plate thicknesses, sandwiched between two 12cm thick solid water blocks, using a Phillips Big Bore CTTM scanner in scout acquisition mode with 120kVp and 200mAs. The transmitted signal (y) was normalized to the air scan signal (y{sub 0}) to get attenuation [i.e., ln(y/y{sub 0})] data for a detector. Results: Below steel plate thickness of 13.4mm, the variations in measured attenuation as a function of view number are characterized by a quantum noise and show increased attenuation with metal thickness. On or above this thickness the attenuation shows discrete levels in addition to the quantum noise. Some views have saturated attenuation value. The histograms of the measured attenuation for up to 36.7mm of steel show this trend. The detector signal is so small that the quantization levels in the analog to digital (A-to-D) converter are visible, a clear indication of photon starvation. Conclusion: Photons reaching the kVCT detector after passing through a thick metal plate are either so low in number that the signal measured has large quantum noise, or are completely absorbed inside the plate creating photon starvation. This is un-interpretable by the mIMPACT algorithm and cannot reduce metal artifacts in kVCT for certain realistic thicknesses of steel

  14. Regional brain glucose use in unstressed rats after two days of starvation

    International Nuclear Information System (INIS)

    Mans, A.M.; Davis, D.W.; Hawkins, R.A.

    1987-01-01

    Regional brain glucose use was measured in conscious, unrestrained, fed rats and after 2 days of starvation, using quantitative autoradiography and [6- 14 C]glucose. Plasma glucose, lactate, and ketone body concentrations and brain glucose and lactate content were measured in separate groups of rats. Glucose concentrations were lower in starved rats in both plasma and brain; plasma ketone body concentrations were elevated. Glucose use was found to be lower throughout the brain by about 12%. While some areas seemed to be affected more than others, statistical analysis showed that none were exceptionally different. The results could not be explained by increased loss of 14 C as lactate or pyruvate during the experimental period, because the arteriovenous differences of these species were insignificant. The calculated contribution by ketone bodies to the total energy consumption was between 3 and 9% for the brain as a whole in the starved rats and could, therefore, partially account for the depression seen in glucose use. It was concluded that glucose oxidation is slightly depressed throughout the brain after 2 days of starvation

  15. Impact of leachable sulfate on the quality of groundwater in the Pocatello aquifer

    International Nuclear Information System (INIS)

    Meehan, C.; Welhan, J.

    1994-01-01

    During the summer of 1993, groundwaters and surface waters were found to have anomalous sulfate concentrations in the Southern Pocatello municipal aquifer in an area known as the Highway Ponds. Leach tests performed on a large pile of road aggregate stockpiled near the Highway Ponds have been identified as the most likely source for the sulfate. Correlating trends of sulfate and chloride concentrations can be found both in the main Pocatello aquifer and in Pocatello Creek groundwaters. The chloride contamination at Pocatello Creek has previously been suggested to be derived from road salt. It is hypothesized that aggregate used in roadbed construction may be responsible for elevated sulfate in the areas groundwater. Chemical modeling has eliminated carbonate precipitation/dissolution reactions in buffering the chemistry of sulfate-impacted groundwater. Ion-exchange with clays is hypothesized to be a more significant process and is being investigated further. 12 refs., 3 figs

  16. Charging Levels of Four tRNA Species in Escherichia coli Rel+ and REL- Strains during Amino Acid Starvation: A Simple Model for the Effect of ppGpp on Translational Accuracy

    DEFF Research Database (Denmark)

    Sørensen, M.A.

    2001-01-01

    Escherichia coli strains mutated in the relA gene lack the ability to produce ppGpp during amino acid starvation. One consequence of this deficiency is a tenfold increase in misincorporation at starved codons compared to the wild-type. Previous work had shown that the charging levels of tRNAs were...... the same in Rel+ and Rel- strains and reduced, at most, two- to fivefold in both strains during starvation. The present reinvestigation of the charging levels of tRNA2Arg, tRNA1Thr, tRNA1Leu and tRNAHis during starvation of isogenic Rel+ and Rel- strains showed that starvation reduced charging levels...... tenfold to 40-fold. This reduction corresponds much better with the decreased rate of protein synthesis during starvation than that reported earlier. The determination of the charging levels of tRNA2Arg and tRNA1Thr during starvation were accurate enough to demonstrate that charging levels were at least...

  17. Unsatisfactory knowledge and use of terminology regarding malnutrition, starvation, cachexia and sarcopenia among dietitians

    NARCIS (Netherlands)

    ter Beek, Lies; Vanhauwaert, Erika; Slinde, Frode; Orrevall, Ylva; Henriksen, Christine; Johansson, Madelene; Vereecken, Carine; Rothenberg, Elisabet; Jager-Wittenaar, Harriët

    2016-01-01

    Clinical signs of malnutrition, starvation, cachexia and sarcopenia overlap, as they all imply muscle wasting to a various extent. However, the underlying mechanisms differ fundamentally and therefore distinction between these phenomena has therapeutic and prognostic implications. We aimed to

  18. Excess Vitamin Intake before Starvation does not Affect Body Mass, Organ Mass, or Blood Variables but Affects Urinary Excretion of Riboflavin in Starving Rats.

    Science.gov (United States)

    Moriya, Aya; Fukuwatari, Tsutomu; Shibata, Katsumi

    2013-01-01

    B-vitamins are important for producing energy from amino acids, fatty acids, and glucose. The aim of this study was to elucidate the effects of excess vitamin intake before starvation on body mass, organ mass, blood, and biological variables as well as on urinary excretion of riboflavin in rats. Adult rats were fed two types of diets, one with a low vitamin content (minimum vitamin diet for optimum growth) and one with a sufficient amount of vitamins (excess vitamin diet). Body mass, organ mass, and blood variables were not affected by excess vitamin intake before starvation. Interestingly, urinary riboflavin excretion showed a different pattern. Urine riboflavin in the excess vitamin intake group declined gradually during starvation, whereas it increased in the low vitamin intake group. Excess vitamin intake before starvation does not affect body mass, organ mass, or blood variables but does affect the urinary excretion of riboflavin in starving rats.

  19. Acute Exacerbations of COPD Are Associated With Increased Expression of Heparan Sulfate and Chondroitin Sulfate in BAL.

    Science.gov (United States)

    Papakonstantinou, Eleni; Klagas, Ioannis; Roth, Michael; Tamm, Michael; Stolz, Daiana

    2016-03-01

    Acute exacerbations of COPD (AECOPDs) are associated with accelerated aggravation of clinical symptoms and deterioration of pulmonary function. The mechanisms by which exacerbations may contribute to airway remodeling and declined lung function are poorly understood. We investigated whether AECOPDs are associated with differential expression of glycosaminoglycans in BAL in a cohort of 97 patients with COPD. Patients with COPD with either stable disease (n = 53) or AECOPD (n = 44) and undergoing diagnostic bronchoscopy were matched for demographics and lung function parameters. Levels of heparan sulfate, chondroitin sulfate, dermatan sulfate, and matrix metalloproteinases (MMPs) in BAL were measured by enzyme-linked immunosorbent assay. Heparan sulfate and chondroitin sulfate were significantly increased in BAL of patients during exacerbations. Levels of heparan sulfate were higher in the BAL of patients with microbial infections. Chondroitin sulfate was negatively correlated with FEV1 % predicted but not with diffusing capacity of lung for carbon monoxide % predicted, indicating that chondroitin sulfate is associated with airway remodeling, leading to obstruction rather than to emphysema. Furthermore, heparan sulfate and chondroitin sulfate were significantly correlated with MMP-9, MMP-2, and MMP-12 in BAL, indicating that they were cleaved from their respective proteoglycans by MMPs and subsequently washed out in BAL. During AECOPD, there is increased expression of heparan sulfate and chondroitin sulfate in BAL. These molecules are significantly correlated with MMPs in BAL, indicating that they may be associated with airway remodeling and may lead to lung function decline during exacerbations of COPD. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  20. Chondroitin Sulfate Perlecan Enhances Collagen Fibril Formation

    DEFF Research Database (Denmark)

    Kvist, A. J.; Johnson, A. E.; Mörgelin, M.

    2006-01-01

    in collagen type II fibril assembly by perlecan-null chondrocytes. Cartilage perlecan is a heparin sulfate or a mixed heparan sulfate/chondroitin sulfate proteoglycan. The latter form binds collagen and accelerates fibril formation in vitro, with more defined fibril morphology and increased fibril diameters...... produced in the presence of perlecan. Interestingly, the enhancement of collagen fibril formation is independent on the core protein and is mimicked by chondroitin sulfate E but neither by chondroitin sulfate D nor dextran sulfate. Furthermore, perlecan chondroitin sulfate contains the 4,6-disulfated...... disaccharides typical for chondroitin sulfate E. Indeed, purified glycosaminoglycans from perlecan-enriched fractions of cartilage extracts contain elevated levels of 4,6-disulfated chondroitin sulfate disaccharides and enhance collagen fibril formation. The effect on collagen assembly is proportional...

  1. Doxycyclin ameliorates a starvation-induced germline tumor in C. elegans daf-18/PTEN mutant background.

    Science.gov (United States)

    Wolf, Tim; Qi, Wenjing; Schindler, Verena; Runkel, Eva Diana; Baumeister, Ralf

    2014-08-01

    Managing available resources is a key necessity of each organism to cope with the environment. The nematode C. elegans responds to nutritional deprivation or harsh environmental conditions with a multitude of developmental adaptations, among them a starvation-induced quiescence at early larval development (L1). daf-18, the C. elegans homolog of the human tumor suppressor gene PTEN, is essential for the maintenance of survival and germline stem cell arrest during the L1 diapause. We show here that daf-18 mutants, independently to their failure to maintain G2 arrest of the primordial germ cells, develop a gonad phenotype after refeeding. This highly penetrant gonadal phenotype is further enhanced by a mutation in shc-1, encoding a protein homologous to the human adaptor ShcA. Features of this phenotype are a tumor-like phenotype encompassing hyper-proliferation of germ cell nuclei and disruption/invasion of the basement membrane surrounding the gonad. The penetrance of this phenotype is reduced by decreasing starvation temperature. In addition, it is also ameliorated in a dose-dependent way by exposure to the antibiotic doxycyclin either during starvation or during subsequent refeeding. Since, in eukaryotic cells, doxycyclin specifically blocks mitochondrial translation, our results suggest that daf-18 and shc-1;daf-18 mutants fail to adapt mitochondrial activity to reduced nutritional availability during early larval developing. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Activation and transfer of sulfate in biological systems (1960); Activation biologique du sulfate et son transfert (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Chapeville, F [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    It examines in this review the successive stages of active sulfate formation and its role in biological synthesis of sulfuric esters. The possible role of active sulfate as intermediary in sulfate reduction is also discussed. (author) [French] On examine dans cette etude les stades successifs de la mise en evidence du sulfate actif, son role dans la formation des esters sulfuriques de natures diverses, ainsi que sa participation eventuelle comme intermediaire au cours de la reduction du sulfate. On decrit aussi un procede de preparation du systeme biologique, generateur du sulfate actif et une methode de synthese chimique. (auteur)

  3. Streptococcus phocae infections associated with starvation in Cape fur seals : case report

    Directory of Open Access Journals (Sweden)

    M.M. Henton

    1999-07-01

    Full Text Available Mortalities and abortions associated with starvation occurred at Cape Cross, Namibia, in Cape fur seals (Arctocephalus pusillus pusillus. Affected seals showed lethargy and emaciation, and the most common pathological signs were those of a respiratory infection, both in adults and offspring. Streptococcus phocae was isolated from adult seals, a cub and aborted foetuses.

  4. Quantitative analysis of glycosaminoglycans, chondroitin/dermatan sulfate, hyaluronic acid, heparan sulfate, and keratan sulfate by liquid chromatography-electrospray ionization-tandem mass spectrometry.

    Science.gov (United States)

    Osago, Harumi; Shibata, Tomoko; Hara, Nobumasa; Kuwata, Suguru; Kono, Michihaya; Uchio, Yuji; Tsuchiya, Mikako

    2014-12-15

    We developed a method using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode for simultaneous quantitative analysis of glycosaminoglycans (GAGs). Using one-shot analysis with our MS/MS method, we demonstrated the simultaneous quantification of a total of 23 variously sulfated disaccharides of four GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 12 heparan sulfates, and 2 keratan sulfates) with a sensitivity of less than 0.5 pmol within 20 min. We showed the differences in the composition of GAG classes and the sulfation patterns between porcine articular cartilage and yellow ligament. In addition to the internal disaccharides described above, some saccharides derived from the nonreducing terminal were detected simultaneously. The simultaneous quantification of both internal and nonreducing terminal saccharides could be useful to estimate the chain length of GAGs. This method would help to establish comprehensive "GAGomic" analysis of biological tissues. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Substrate metabolism in the metabolic response to injury

    NARCIS (Netherlands)

    Romijn, J. A.

    2000-01-01

    In healthy subjects the metabolic response to starvation invokes regulatory mechanisms aimed at conservation of protein mass. This response is characterized by a decrease in energy expenditure and a progressive decrease in urinary N excretion. Many non-endocrine diseases induce anorexia and a

  6. Constraining Δ33S signatures of Archean seawater sulfate with carbonate-associated sulfate

    Science.gov (United States)

    Peng, Y.; Bao, H.; Bekker, A.; Hofmann, A.

    2017-12-01

    Non-mass dependent sulfur isotope deviation of S-bearing phases in Archean sedimentary strata, and expressed as Δ33S, has a consistent pattern, i.e., sulfide (pyrite) predominantly bear positive Δ33S values, while Paleoarchean sulfate (barite) has negative Δ33S values. This pattern was later corroborated by observations of negative Δ33S values in Archean volcanogenic massive sulfide deposits and negative Δ33S values in early diagenetic nodular pyrite with a wide range of δ34S values, which is thought to be due to microbial sulfate reduction. These signatures have provided a set of initial conditions for a mechanistic interpretation at physical chemistry level. Unlike the younger geological times when large bodies of seawater evaporite deposits are common, to expand seawater sulfate records, carbonate-associated sulfate (CAS) was utilized as a proxy for ancient seawater sulfate. CAS extracted from the Archean carbonates carries positive Δ33S values. However, CAS could be derived from pyrite oxidation following exposure to modern oxidizing conditions and/or during laboratory extraction procedures. It is, therefore, important for us understanding context of the overall early earth atmospheric condition to empirically confirm whether Archean seawater sulfate was generally characterized by negative Δ33S signatures. Combined δ18O, Δ17O, δ34S, and Δ33S analyses of sequentially extracted water-leachable sulfate (WLS) and acid-leachable sulfate (ALS = CAS) and δ34S and Δ33S analyses of pyrite can help to identify the source of extracted sulfate. We studied drill-core samples of Archean carbonates from the 2.55 Ga Malmani and Campell Rand supgroups, South Africa. Our preliminary results show that 1) neither WLS nor ALS were extracted from samples with extremely low pyrite contents (less than 0.05 wt.%); 2) extractable WLS and ALS is present in samples with relatively high pyrite contents (more than 1 wt.%), and that δ34S and Δ33S values of WLS, ALS, and

  7. Protein synthesis and degradation during starvation-induced cardiac atrophy in rabbits

    International Nuclear Information System (INIS)

    Samarel, A.M.; Parmacek, M.S.; Magid, N.M.; Decker, R.S.; Lesch, M.

    1987-01-01

    To determine the relative importance of protein degradation in the development of starvation-induced cardiac atrophy, in vivo fractional synthetic rates of total cardiac protein, myosin heavy chain, actin, light chain 1, and light chain 2 were measured in fed and fasted rabbits by continuous infusion of [ 3 H] leucine. In addition, the rate of left ventricular protein accumulation and loss were assessed in weight-matched control and fasted rabbits. Rates of total cardiac protein degradation were then estimated as the difference between rates of synthesis and growth. Fasting produced left ventricular atrophy by decreasing the rate of left ventricular protein synthesis (34.8 +/- 1.4, 27.3 +/- 3.0, and 19.3 +/- 1.2 mg/day of left ventricular protein synthesized for 0-, 3-, and 7-day fasted rabbits, respectively). Inhibition of contractile protein synthesis was evident by significant reductions in the fractional synthetic rates of all myofibrillar protein subunits. Although fractional rates of protein degradation increased significantly within 7 days of fasting, actual amounts of left ventricular protein degraded per day were unaffected. Thus, prolonged fasting profoundly inhibits the synthesis of new cardiac protein, including the major protein constituents of the myofibril. Both this inhibition in new protein synthesis as well as a smaller but significant reduction in the average half-lives of cardiac proteins are responsible for atrophy of the heart in response to fasting

  8. Effects of sulfate deprivation on the production of chondroitin/dermatan sulfate by cultures of skin fibroblasts from normal and diabetic individuals

    International Nuclear Information System (INIS)

    Silbert, C.K.; Humphries, D.E.; Palmer, M.E.; Silbert, J.E.

    1991-01-01

    Human skin fibroblast monolayer cultures from two normal men, three Type I diabetic men, and one Type I diabetic woman were incubated with [3H]glucosamine in the presence of diminished concentrations of sulfate. Although total synthesis of [3H]chondroitin/dermatan glycosaminoglycans varied somewhat between cell lines, glycosaminoglycan production was not affected within any line when sulfate levels were decreased from 0.3 mM to 0.06 mM to 0.01 mM to 0 added sulfate. Lowering of sulfate concentrations resulted in diminished sulfation of chondroitin/dermatan in a progressive manner, so that overall sulfation dropped to as low as 19% for one of the lines. Sulfation of chondroitin to form chondroitin 4-sulfate and chondroitin 6-sulfate was progressively and equally affected by decreasing the sulfate concentration in the culture medium. However, sulfation to form dermatan sulfate was preserved to a greater degree, so that the relative proportion of dermatan sulfate to chondroitin sulfate increased. Essentially all the nonsulfated residues were susceptible to chondroitin AC lyase, indicating that little epimerization of glucuronic acid residues to iduronic acid had occurred in the absence of sulfation. These results confirm the previously described dependency of glucuronic/iduronic epimerization on sulfation, and indicate that sulfation of the iduronic acid-containing disaccharide residues of dermatan can take place with sulfate concentrations lower than those needed for 6-sulfation and 4-sulfation of the glucuronic acid-containing disaccharide residues of chondroitin. There were considerable differences among the six fibroblast lines in susceptibility to low sulfate medium and in the proportion of chondroitin 6-sulfate, chondroitin 4-sulfate, and dermatan sulfate. However, there was no pattern of differences between normals and diabetics

  9. INTRACELLULAR SYNTHESIS OF CHONDROITIN SULFATE

    Science.gov (United States)

    Dziewiatkowski, Dominic D.

    1962-01-01

    In autoradiograms of slices of costal cartilage, incubated for 4 hours in a salt solution containing S35-sulfate and then washed extensively and dehydrated, about 85 per cent of the radioactivity was assignable to the chondrocytes. From alkaline extracts of similarly prepared slices of cartilage, 64 to 83 per cent of the total sulfur-35 in the slices was isolated as chondroitin sulfate by chromatography on an anion-exchange resin. In view of the estimate that only about 15 per cent of the radioactivity was in the matrix, the isolation of 64 to 83 per cent of the total sulfur-35 as chondroitin sulfate is a strong argument that the chondrocytes are the loci in which chondroitin sulfate(s) is synthesized. PMID:13888910

  10. Synthesis of N-oleyl O-sulfate chitosan from methyl oleate with O-sulfate chitosan as edible film material

    Science.gov (United States)

    Daniel; Sihaloho, O.; Saleh, C.; Magdaleni, A. R.

    2018-04-01

    The research on the synthesis of N-oleyl O-sulfate chitosan through sulfonation reaction on chitosan with ammonium sulfate and followed by amidation reaction using methyl oleate has been done. In this study, chitosan was chemically modified into N-oleyl O-sulfatechitosan as an edible film making material. N-oleyl O-sulfate chitosan was synthesized by reaction between methyl oleate and O-sulfate chitosan. Wherein the depleted chitosan of O-sulfate chitosan into O-sulfate chitosan was obtained by reaction of sulfonation between ammonium sulfate and chitosan aldimine. While chitosan aldimine was obtained through reaction between chitosan with acetaldehyde. The structure of N-oleyl O-sulfate chitosan was characterized by FT-IR analysis which showed vibration uptake of C-H sp3 group, S=O group, and carbonyl group C=O of the ester. The resulting of N-oleyl O-sulfate chitosan yielded a percentage of 93.52%. Hydrophilic-Lipophilic Balance (HLB) test results gave a value of 6.68. In the toxicity test results of N-oleyl O-sulfate chitosan obtained LC50 value of 3738.4732 ppm. In WVTR (Water Vapor Transmission Rate) test results for chitosan film was 407.625 gram/m2/24 hours and N-oleylO-sulfate chitosan film was 201.125 gram/m2/24 hours.

  11. Octopamine and Tyramine Contribute Separately to the Counter-Regulatory Response to Sugar Deficit in Drosophila

    Directory of Open Access Journals (Sweden)

    Christine Damrau

    2018-01-01

    Full Text Available All animals constantly negotiate external with internal demands before and during action selection. Energy homeostasis is a major internal factor biasing action selection. For instance, in addition to physiologically regulating carbohydrate mobilization, starvation-induced sugar shortage also biases action selection toward food-seeking and food consumption behaviors (the counter-regulatory response. Biogenic amines are often involved when such widespread behavioral biases need to be orchestrated. In mammals, norepinephrine (noradrenalin is involved in the counterregulatory response to starvation-induced drops in glucose levels. The invertebrate homolog of noradrenalin, octopamine (OA and its precursor tyramine (TA are neuromodulators operating in many different neuronal and physiological processes. Tyrosine-ß-hydroxylase (tßh mutants are unable to convert TA into OA. We hypothesized that tßh mutant flies may be aberrant in some or all of the counter-regulatory responses to starvation and that techniques restoring gene function or amine signaling may elucidate potential mechanisms and sites of action. Corroborating our hypothesis, starved mutants show a reduced sugar response and their hemolymph sugar concentration is elevated compared to control flies. When starved, they survive longer. Temporally controlled rescue experiments revealed an action of the OA/TA-system during the sugar response, while spatially controlled rescue experiments suggest actions also outside of the nervous system. Additionally, the analysis of two OA- and four TA-receptor mutants suggests an involvement of both receptor types in the animals' physiological and neuronal response to starvation. These results complement the investigations in Apis mellifera described in our companion paper (Buckemüller et al., 2017.

  12. Excess Vitamin Intake before Starvation does not Affect Body Mass, Organ Mass, or Blood Variables but Affects Urinary Excretion of Riboflavin in Starving Rats

    Directory of Open Access Journals (Sweden)

    Aya Moriya

    2013-01-01

    Full Text Available B-vitamins are important for producing energy from amino acids, fatty acids, and glucose. The aim of this study was to elucidate the effects of excess vitamin intake before starvation on body mass, organ mass, blood, and biological variables as well as on urinary excretion of riboflavin in rats. Adult rats were fed two types of diets, one with a low vitamin content (minimum vitamin diet for optimum growth and one with a sufficient amount of vitamins (excess vitamin diet. Body mass, organ mass, and blood variables were not affected by excess vitamin intake before starvation. Interestingly, urinary riboflavin excretion showed a different pattern. Urine riboflavin in the excess vitamin intake group declined gradually during starvation, whereas it increased in the low vitamin intake group. Excess vitamin intake before starvation does not affect body mass, organ mass, or blood variables but does affect the urinary excretion of riboflavin in starving rats.

  13. Biotin starvation causes mitochondrial protein hyperacetylation and partial rescue by the SIRT3-like deacetylase Hst4p

    DEFF Research Database (Denmark)

    Madsen, Christian Toft; Sylvestersen, Kathrine Beck; Young, Clifford

    2015-01-01

    deficiency. Upregulated mitochondrial acetylation sites correlate with the cellular deficiency of the Hst4p deacetylase, and a biotin-starvation-induced accumulation of Hst4p in mitochondria supports a role for Hst4p in lowering mitochondrial acetylation. We show that biotin starvation and knockout of Hst4p...... cause alterations in cellular respiration and an increase in reactive oxygen species (ROS). These results suggest that Hst4p plays a pivotal role in biotin metabolism and cellular energy homeostasis, and supports that Hst4p is a functional yeast homologue of the sirtuin deacetylase SIRT3. With biotin...

  14. Effect of acute maternal starvation on tyrosine metabolism and protein synthesis in fetal sheep

    International Nuclear Information System (INIS)

    Krishnamurti, C.R.; Schaefer, A.L.

    1984-01-01

    To determine the effects of acute maternal starvation on intrauterine growth, tyrosine concentration and specific activity values in plasma, intracellular free and protein bound pools were determined in catheterized ovine fetuses following an 8 h continuous infusion of L-[2,3,5,6 3 H] or L-[U- 14 C] tyrosine into the ewe and fetus respectively at 115-125 days of gestation. From the kinetic data the rates of whole body and tissue fractional protein synthesis were calculated. Although placental protein synthesis was not significantly changed as a result of acute maternal starvation, fetal whole body protein synthesis was reduced from 63 g/d/kg in the fed to 25 g/d/kg in the starved condition. There was also a 10 fold reduction in the net placental transfer of tyrosine to the fetus in the starved ewes. In addition, a three fold increase was observed in the quantity of tyrosine used for oxidation by the fetuses of starved ewes, changing from 5.2% of tyrosine net utilization in the fed to 13.7% in the starved condition. Significant reductions in tissue fractional protein synthesis rates were also seen in the liver, brain, lung kidney and GIT tissues from 78, 37, 65, 45 and 71%/d respectively in the fed to 12, 10, 23, 22 and 35%/d in the fetuses of starved ewes. The data indicate that during acute maternal starvation the sheep fetus utilizes more tyrosine for oxidation and less for anabolic purposes which is reflected in a decrease both in whole body and tissue fractional rates of protein synthesis

  15. 21 CFR 184.1261 - Copper sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Copper sulfate. 184.1261 Section 184.1261 Food and... Substances Affirmed as GRAS § 184.1261 Copper sulfate. (a) Copper sulfate (cupric sulfate, CuSO4·5H2O, CAS... the reaction of sulfuric acid with cupric oxide or with copper metal. (b) The ingredient must be of a...

  16. Heritability and clinical determinants of serum indoxyl sulfate and p-cresyl sulfate, candidate biomarkers of the human microbiome enterotype.

    Directory of Open Access Journals (Sweden)

    Liesbeth Viaene

    Full Text Available BACKGROUND: Indoxyl sulfate and p-cresyl sulfate are unique microbial co-metabolites. Both co-metabolites have been involved in the pathogenesis of accelerated cardiovascular disease and renal disease progression. Available evidence suggests that indoxyl sulfate and p-cresyl sulfate may be considered candidate biomarkers of the human enterotype and may help to explain the link between diet and cardiovascular disease burden. OBJECTIVE AND DESIGN: Information on clinical determinants and heritability of indoxyl sulfate and p-cresyl sulfate serum is non-existing. To clarify this issue, the authors determined serum levels of indoxyl sulfate and p-cresyl sulfate in 773 individuals, recruited in the frame of the Flemish Study on Environment, Genes and Health Outcomes (FLEMENGHO study. RESULTS: Serum levels of indoxyl sulfate and p-cresyl sulfate amounted to 3.1 (2.4-4.3 and 13.0 (7.4-21.5 μM, respectively. Regression analysis identified renal function, age and sex as independent determinants of both co-metabolites. Both serum indoxyl sulfate (h2 = 0.17 and p-cresyl sulfate (h2 = 0.18 concentrations showed moderate but significant heritability after adjustment for covariables, with significant genetic and environmental correlations for both co-metabolites. LIMITATIONS: Family studies cannot provide conclusive evidence for a genetic contribution, as confounding by shared environmental effects can never be excluded. CONCLUSIONS: The heritability of indoxyl sulfate and p-cresyl sulfate is moderate. Besides genetic host factors and environmental factors, also renal function, sex and age influence the serum levels of these co-metabolites.

  17. Quantification and isotopic analysis of intracellular sulfur metabolites in the dissimilatory sulfate reduction pathway

    Science.gov (United States)

    Sim, Min Sub; Paris, Guillaume; Adkins, Jess F.; Orphan, Victoria J.; Sessions, Alex L.

    2017-06-01

    Microbial sulfate reduction exhibits a normal isotope effect, leaving unreacted sulfate enriched in 34S and producing sulfide that is depleted in 34S. However, the magnitude of sulfur isotope fractionation is quite variable. The resulting changes in sulfur isotope abundance have been used to trace microbial sulfate reduction in modern and ancient ecosystems, but the intracellular mechanism(s) underlying the wide range of fractionations remains unclear. Here we report the concentrations and isotopic ratios of sulfur metabolites in the dissimilatory sulfate reduction pathway of Desulfovibrio alaskensis. Intracellular sulfate and APS levels change depending on the growth phase, peaking at the end of exponential phase, while sulfite accumulates in the cell during stationary phase. During exponential growth, intracellular sulfate and APS are strongly enriched in 34S. The fractionation between internal and external sulfate is up to 49‰, while at the same time that between external sulfate and sulfide is just a few permil. We interpret this pattern to indicate that enzymatic fractionations remain large but the net fractionation between sulfate and sulfide is muted by the closed-system limitation of intracellular sulfate. This 'reservoir effect' diminishes upon cessation of exponential phase growth, allowing the expression of larger net sulfur isotope fractionations. Thus, the relative rates of sulfate exchange across the membrane versus intracellular sulfate reduction should govern the overall (net) fractionation that is expressed. A strong reservoir effect due to vigorous sulfate reduction might be responsible for the well-established inverse correlation between sulfur isotope fractionation and the cell-specific rate of sulfate reduction, while at the same time intraspecies differences in sulfate uptake and/or exchange rates could account for the significant scatter in this relationship. Our approach, together with ongoing investigations of the kinetic isotope

  18. Antimicrobial efficacy of chlorine dioxide against Candida albicans in stationary and starvation phases in human root canal: An in-vitro study

    Directory of Open Access Journals (Sweden)

    Shirur Krishnaraj Somayaji

    2014-01-01

    Full Text Available Introduction: Candida albicans (C. albicans is the most commonly isolated fungal pathogen from dental root canal. C. albicans forms biofilm and develops resistance against root canal irrigants . This study determines the fungicidal efficacy of 13.8% chlorine dioxide in extracted human teeth at stationary and starvation phases of C. albicans. Materials and Methods: Teeth were decoronated and coronal portion of the roots were prepared into blocks, which were incubated at 37°C with C. albicans for five days. The samples were treated with chlorine dioxide for 12 and 20 minutes. Total of fifty blocks were taken in the study. Colony-forming units were counted in Sabourauds dextrose agar and scanning electron microscopic observation was done. Data were analyzed by one-way ANOVA and Bonferoni′s post hoc test. Results: Teeth at stationary phase (12 min showed mean colony count of 28,000 ± 1814 which is significantly (P < 0.001 less than control group. Teeth at starvation phase (12 min showed colony count of 65,600 ± 1912 which is also significantly (P < 0.001 less than control group. Teeth irrigated at stationary phase (20 min showed mean colony count of 23,400 ± 1776 (P < 0.001. Teeth irrigated at starvation phase (20 min showed mean colony count of 48,100 ± 1663 which is also significantly (P < 0.001 less than that of control group. Conclusion: Treatment of chlorine dioxide reduces the C. albicans count in root canals of extracted human teeth at stationary and starvation phases. Efficacy of chlorine dioxide against C. albicans is relatively higher in stationary phase than that of starvation phase.

  19. The electrical and thermal properties of sodium sulfate mixed with lithium sulfate, yttrium sulfate, and silicon dioxide

    International Nuclear Information System (INIS)

    Imanaka, N.; Yamaguchi, Y.; Adachi, G.; Shiokawa, J.

    1986-01-01

    Sodium sulfate mixed with lithium sulfate, yttrium sulfate, and silicon dioxide was prepared. The thermal and electrical properties of its phases were investigated. The Na 2 SO 4 -Li 2 SO 4 -Y 2 (SO 4 ) 3 SiO 2 samples are similar to the Na 2 SO 4 -I phase (a high temperature phase), which is appreciably effective for Na + ionic conduction. Phase transformation was considerably suppressed by mixing. Electromotive force (EMF) was measured, using Na 2 SO 4 -Li 2 SO 4 -Y 2 (SO 4 ) 3 -SiO 2 as a solid electrolyte, by constructing an SO 2 gas concentration cell. The measured EMF's at 823 and 773 K were in fairly good accordance with the calculated EMF's for inlet SO 2 gas concentration between 30 ppm and 1%, and 500 ppm and 0.5% respectively

  20. 21 CFR 172.822 - Sodium lauryl sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium lauryl sulfate. 172.822 Section 172.822 Food... Multipurpose Additives § 172.822 Sodium lauryl sulfate. The food additive sodium lauryl sulfate may be safely... specifications: (1) It is a mixture of sodium alkyl sulfates consisting chiefly of sodium lauryl sulfate [CH2(CH2...

  1. Insertion-Sequence-Mediated Mutations Isolated During Adaptation to Growth and Starvation in Lactococcus lactis.

    NARCIS (Netherlands)

    Visser, de J.A.G.M.; Akkermans, A.D.L.; Hoekstra, R.F.; Vos, de W.M.

    2004-01-01

    We studied the activity of three multicopy insertion sequence (IS) elements in 12 populations of Lactococcus lactis IL1403 that evolved in the laboratory for 1000 generations under various environmental conditions (growth or starvation and shaken or stationary). Using RFLP analysis of single-clone

  2. Purification and sequence characterization of chondroitin sulfate and dermatan sulfate from fishes.

    Science.gov (United States)

    Lin, Na; Mo, Xiaoli; Yang, Yang; Zhang, Hong

    2017-04-01

    Chondroitin sulfate (CS) and dermatan sulfate (DS) were extracted and purified from skins or bones of salmon (Salmo salar), snakehead (Channa argus), monkfish (Lophius litulon) and skipjack tuna (Katsuwonus pelamis). Size, structural sequences and sulfate groups of oligosaccharides in the purified CS and DS could be characterized and identified using high performance liquid chromatography (HPLC) combined with Orbitrap mass spectrometry. CS and DS chain structure varies depending on origin, but motif structure appears consistent. Structures of CS and DS oligosaccharides with different size and sulfate groups were compared between fishes and other animals, and results showed that some minor differences of special structures could be identified by hydrophilic interaction chromatography-liquid chromatography-fourier transform-mass/mass spectrometry (HILIC-LC-FT-MS/MS). For example, data showed that salmon and skipjack CS had a higher percentage content of high-level sulfated oligosaccharides than that porcine CS. In addition, structural information of different origins of CS and DS was analyzed by principal component analysis (PCA) and results showed that CS and DS samples could be differentiated according to their molecular conformation and oligosaccharide fragments information. Understanding CS and DS structure derived from different origins may lead to the production of CS or DS with unique disaccharides or oligosaccharides sequence composition and biological functions.

  3. Treatment and electricity harvesting from sulfate/sulfide-containing wastewaters using microbial fuel cell with enriched sulfate-reducing mixed culture

    International Nuclear Information System (INIS)

    Lee, Duu-Jong; Lee, Chin-Yu; Chang, Jo-Shu

    2012-01-01

    Highlights: ► We started up microbial fuel cell (MFC) using enriched sulfate-reducing mixed culture. ► Sulfate-reducing bacteria and anode-respiring bacteria were enriched in anodic biofilms. ► The MFC effectively remove sulfate to elementary sulfur in the presence of lactate. ► The present device can treat sulfate laden wastewaters with electricity harvesting. - Abstract: Anaerobic treatment of sulfate-laden wastewaters can produce excess sulfide, which is corrosive to pipelines and is toxic to incorporated microorganisms. This work started up microbial fuel cell (MFC) using enriched sulfate-reducing mixed culture as anodic biofilms and applied the so yielded MFC for treating sulfate or sulfide-laden wastewaters. The sulfate-reducing bacteria in anodic biofilm effectively reduced sulfate to sulfide, which was then used by neighboring anode respiring bacteria (ARB) as electron donor for electricity production. The presence of organic carbons enhanced MFC performance since the biofilm ARB were mixotrophs that need organic carbon to grow. The present device introduces a route for treating sulfate laden wastewaters with electricity harvesting.

  4. Treatment and electricity harvesting from sulfate/sulfide-containing wastewaters using microbial fuel cell with enriched sulfate-reducing mixed culture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Duu-Jong, E-mail: cedean@mail.ntust.edu.tw [Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan (China); Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan (China); Lee, Chin-Yu [Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan (China); Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan (China); Center for Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan (China); Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan, Taiwan (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer We started up microbial fuel cell (MFC) using enriched sulfate-reducing mixed culture. Black-Right-Pointing-Pointer Sulfate-reducing bacteria and anode-respiring bacteria were enriched in anodic biofilms. Black-Right-Pointing-Pointer The MFC effectively remove sulfate to elementary sulfur in the presence of lactate. Black-Right-Pointing-Pointer The present device can treat sulfate laden wastewaters with electricity harvesting. - Abstract: Anaerobic treatment of sulfate-laden wastewaters can produce excess sulfide, which is corrosive to pipelines and is toxic to incorporated microorganisms. This work started up microbial fuel cell (MFC) using enriched sulfate-reducing mixed culture as anodic biofilms and applied the so yielded MFC for treating sulfate or sulfide-laden wastewaters. The sulfate-reducing bacteria in anodic biofilm effectively reduced sulfate to sulfide, which was then used by neighboring anode respiring bacteria (ARB) as electron donor for electricity production. The presence of organic carbons enhanced MFC performance since the biofilm ARB were mixotrophs that need organic carbon to grow. The present device introduces a route for treating sulfate laden wastewaters with electricity harvesting.

  5. Response And Recovery Of Sulfate-Reducing Biochemical Reactors From Aerobic Stress Events (Presentation)

    Science.gov (United States)

    Microbially-mediated treatment of mining-influenced water (MIW) through the implementation of sulfate-reducing biochemical reactors (BCR) is an attractive option for passive, in situ remediation with low operating costs and reduced maintenance requirements. However, BCRs can be ...

  6. Mercury and lead tolerance in hypersaline sulfate-reducing bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Harithsa, S.; Kerkar, S.; LokaBharathi, P.A.

    -sporulating, non-motile rods lacking in desulfoviridin and cytochromes. Examination of these isolates for heavy metal tolerance and response studies in terms of growth and sulfate-reducing activity (SRA) were carried out using HgCl sub(2) and Pb(NO sub(3)) sub(2...

  7. Leptin suppresses semi-starvation induced hyperactivity in rats: implications for anorexia nervosa.

    Science.gov (United States)

    Exner, C; Hebebrand, J; Remschmidt, H; Wewetzer, C; Ziegler, A; Herpertz, S; Schweiger, U; Blum, W F; Preibisch, G; Heldmaier, G; Klingenspor, M

    2000-09-01

    Semi-starvation induced hyperactivity (SIH) occurs in rodents upon caloric restriction. We hypothesized that SIH is triggered by the decline in leptin secretion associated with food restriction. To test this hypothesis, rats, which had established a stable level of activity, were treated with leptin or vehicle via implanted minipumps concomitantly to initiation of food restriction for 7 days. In a second experiment treatment was initiated after SIH had already set in. In contrast to the vehicle-treated rats, which increased their baseline activity level by 300%, the development of SIH was suppressed by leptin. Furthermore, leptin was able to stop SIH, after it had set in. These results underscore the assumed major role of leptin in the adaptation to semi-starvation. Because SIH has been viewed as a model for anorexia nervosa, we also assessed subjective ratings of motor restlessness in 30 patients with this eating disorder in the emaciated state associated with hypoleptinemia and after increments in leptin secretion brought upon by therapeutically induced weight gain. Hypoleptinemic patients ranked their motor restlessness higher than upon attainment of their maximal leptin level during inpatient treatment. Thus, hypoleptinemia might also contribute to the hyperactivity frequently associated with anorexia nervosa.

  8. Biosynthesis and function of chondroitin sulfate.

    Science.gov (United States)

    Mikami, Tadahisa; Kitagawa, Hiroshi

    2013-10-01

    Chondroitin sulfate proteoglycans (CSPGs) are principal pericellular and extracellular components that form regulatory milieu involving numerous biological and pathophysiological phenomena. Diverse functions of CSPGs can be mainly attributed to structural variability of their polysaccharide moieties, chondroitin sulfate glycosaminoglycans (CS-GAG). Comprehensive understanding of the regulatory mechanisms for CS biosynthesis and its catabolic processes is required in order to understand those functions. Here, we focus on recent advances in the study of enzymatic regulatory pathways for CS biosynthesis including successive modification/degradation, distinct CS functions, and disease phenotypes that have been revealed by perturbation of the respective enzymes in vitro and in vivo. Fine-tuned machineries for CS production/degradation are crucial for the functional expression of CS chains in developmental and pathophysiological processes. Control of enzymes responsible for CS biosynthesis/catabolism is a potential target for therapeutic intervention for the CS-associated disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Isolation of a sulfate reducing bacterium and its application in sulfate ...

    African Journals Online (AJOL)

    The results show that the effect of C. freundii in removing sulfate was best when the temperature was 32°C, pH was 7.0, COD/SO42- was 5.0 and the initial SO42- concentration was 1500 mg/L. Also, the SRB was inoculated onto an up-flow anaerobic sludge bed (UASB) to remove sulfate in actual tannery wastewater.

  10. Starvation and diet according to the Vinzenz Priessnitz family water book of 1847.

    Science.gov (United States)

    Rohde, Jürgen

    2007-02-01

    Vinzenz Priessnitz (1799-1851) did not only carry out water treatments within the scope of his cure, but also movement therapy, aerial and solar baths, natural lifestyle and, above all, diet therapy. According to the literature Priessnitz only seldom allowed starvation within his cure because this would break his preferred principle of restoration. Nevertheless, the widely unknown 'Vinzenz Priessnitz family water book' which he dictated to his daughter Sophie in 1847, includes 13 orders of starvation for a series of indications (breast inflammations, pneumonia, pulmonary embolism, cholera, intestines inflammation, tapeworm) and symptoms (diarrhoea and vomiting, heart cramp, head woe, faint, stone pains, feeling of sickness). Furthermore, it comprises diet recommendations on cold water drinking, milk and cold confection of pastry, compote and buttermilk, vegetables, fruit and strawberries, fruit and frozen food, no meat, little meat and cold food. In the view of the literature, these diet principles and means as well as their applications then and now are discussed. As for those days the Priessnitz diet was quite modern, manifold, logic and 'natural'.

  11. [Effect of starvation on blood protein levels in the population of Dobrinja (1992-1995)].

    Science.gov (United States)

    Hasković, E

    2000-01-01

    In nutritional protein deficiency, numerous studies verified utilization of amino acids generated from tissue degradation in intensive protein synthesis. Unlike liver, muscle protein synthesis is extremely dependent on external supplies of essential amino acids. Prolonged nutritional protein deficiency results in decrease of body weight as well as total protein concentration, in particular in early days of starvation. In prolonged starvation during the war, significant decrease of body weight was registered in 70 subjects while their total protein concentration remained within the expected range and did not significantly differ the values recorded in the control group. Concentration of serum albumines in the control group was lower than the concentration recorded in the tested group, while the serum globulins concentration was higher in the control group. Although the difference in body weight between the tested and the control group was statistically significant, no significant difference in the concentration of total proteins, albumines and globulines was recorded.

  12. Divergent Synthesis of Chondroitin Sulfate Disaccharides and Identification of Sulfate Motifs that Inhibit Triple Negative Breast Cancer

    Science.gov (United States)

    Wei Poh, Zhong; Heng Gan, Chin; Lee, Eric J.; Guo, Suxian; Yip, George W.; Lam, Yulin

    2015-09-01

    Glycosaminoglycans (GAGs) regulate many important physiological processes. A pertinent issue to address is whether GAGs encode important functional information via introduction of position specific sulfate groups in the GAG structure. However, procurement of pure, homogenous GAG motifs to probe the “sulfation code” is a challenging task due to isolation difficulty and structural complexity. To this end, we devised a versatile synthetic strategy to obtain all the 16 theoretically possible sulfation patterns in the chondroitin sulfate (CS) repeating unit; these include rare but potentially important sulfated motifs which have not been isolated earlier. Biological evaluation indicated that CS sulfation patterns had differing effects for different breast cancer cell types, and the greatest inhibitory effect was observed for the most aggressive, triple negative breast cancer cell line MDA-MB-231.

  13. Short-term starvation with a near-fatal asthma attack induced ketoacidosis in a nondiabetic pregnant woman: A case report.

    Science.gov (United States)

    Wei, Kuang-Yu; Chang, Shan-Yueh; Wang, Sheng-Huei; Su, Her-Young; Tsai, Chen-Liang

    2016-06-01

    Life-threatening refractory metabolic acidosis due to starvation ketoacidosis is rarely reported, even among nondiabetic pregnant women, and may be overlooked. Furthermore, stressful situations may increase the acidosis severity.In the present case, a nondiabetic multiparous woman was admitted for a near-fatal asthma attack and vomiting during the third trimester of pregnancy. She was intubated and rapidly developed high anion gap metabolic acidosis. We diagnosed the patient with starvation ketoacidosis based on vomiting with concomitant periods of stress during pregnancy and the absence of other causes of high anion gap metabolic acidosis. She responded poorly to standard treatment, although the ketoacidosis and asthma promptly resolved after an emergency caesarean section. The patient and her baby were safely discharged.Short-term starvation, if it occurs during periods of stress and medication, can result in life-threatening ketoacidosis, even among nondiabetic women during the third trimester of pregnancy. Awareness of this condition may facilitate prompt recognition and proactive treatment for dietary and stress control, and emergent interventions may also improve outcomes.

  14. Sulfate-reducing bacteria mediate thionation of diphenylarsinic acid under anaerobic conditions.

    Science.gov (United States)

    Guan, Ling; Shiiya, Ayaka; Hisatomi, Shihoko; Fujii, Kunihiko; Nonaka, Masanori; Harada, Naoki

    2015-02-01

    Diphenylarsinic acid (DPAA) is often found as a toxic intermediate metabolite of diphenylchloroarsine or diphenylcyanoarsine that were produced as chemical warfare agents and were buried in soil after the World Wars. In our previous study Guan et al. (J Hazard Mater 241-242:355-362, 2012), after application of sulfate and carbon sources, anaerobic transformation of DPAA in soil was enhanced with the production of diphenylthioarsinic acid (DPTAA) as a main metabolite. This study aimed to isolate and characterize anaerobic soil microorganisms responsible for the metabolism of DPAA. First, we obtained four microbial consortia capable of transforming DPAA to DPTAA at a high transformation rate of more than 80% after 4 weeks of incubation. Sequencing for the bacterial 16S rRNA gene clone libraries constructed from the consortia revealed that all the positive consortia contained Desulfotomaculum acetoxidans species. In contrast, the absence of dissimilatory sulfite reductase gene (dsrAB) which is unique to sulfate-reducing bacteria was confirmed in the negative consortia showing no DPAA reduction. Finally, strain DEA14 showing transformation of DPAA to DPTAA was isolated from one of the positive consortia. The isolate was assigned to D. acetoxidans based on the partial 16S rDNA sequence analysis. Thionation of DPAA was also carried out in a pure culture of a known sulfate-reducing bacterial strain, Desulfovibrio aerotolerans JCM 12613(T). These facts indicate that sulfate-reducing bacteria are microorganisms responsible for the transformation of DPAA to DPTAA under anaerobic conditions.

  15. Quantitative proteomics reveals altered expression of extracellular matrix related proteins of human primary dermal fibroblasts in response to sulfated hyaluronan and collagen applied as artificial extracellular matrix.

    Science.gov (United States)

    Müller, Stephan A; van der Smissen, Anja; von Feilitzsch, Margarete; Anderegg, Ulf; Kalkhof, Stefan; von Bergen, Martin

    2012-12-01

    Fibroblasts are the main matrix producing cells of the dermis and are also strongly regulated by their matrix environment which can be used to improve and guide skin wound healing processes. Here, we systematically investigated the molecular effects on primary dermal fibroblasts in response to high-sulfated hyaluronan [HA] (hsHA) by quantitative proteomics. The comparison of non- and high-sulfated HA revealed regulation of 84 of more than 1,200 quantified proteins. Based on gene enrichment we found that sulfation of HA alters extracellular matrix remodeling. The collagen degrading enzymes cathepsin K, matrix metalloproteinases-2 and -14 were found to be down-regulated on hsHA. Additionally protein expression of thrombospondin-1, decorin, collagen types I and XII were reduced, whereas the expression of trophoblast glycoprotein and collagen type VI were slightly increased. This study demonstrates that global proteomics provides a valuable tool for revealing proteins involved in molecular effects of growth substrates for further material optimization.

  16. Metabolic Flexibility of Sulfate Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Caroline M. Plugge

    2011-05-01

    Full Text Available Dissimilatory sulfate-reducing prokaryotes (SRB are a very diverse group of anaerobic bacteria that are omnipresent in nature and play an imperative role in the global cycling of carbon and sulfur. In anoxic marine sediments sulfate reduction accounts for up to 50% of the entire organic mineralization in coastal and shelf ecosystems where sulfate diffuses several meters deep into the sediment. As a consequence, SRB would be expected in the sulfate-containing upper sediment layers, whereas methanogenic Archaea would be expected to succeed in the deeper sulfate-depleted layers of the sediment. Where sediments are high in organic matter, sulfate is depleted at shallow sediment depths, and biogenic methane production will occur. In the absence of sulfate, many SRB ferment organic acids and alcohols, producing hydrogen, acetate, and carbon dioxide, and may even rely on hydrogen- and acetate-scavenging methanogens to convert organic compounds to methane. SRB can establish two different life styles, and these can be termed as sulfidogenic and acetogenic, hydrogenogenic metabolism. The advantage of having different metabolic capabilities is that it raises the chance of survival in environments when electron acceptors become depleted. In marine sediments, SRB and methanogens do not compete but rather complement each other in the degradation of organic matter.Also in freshwater ecosystems with sulfate concentrations of only 10-200 μM, sulfate is consumed efficiently within the top several cm of the sediments. Here, many of the δ-Proteobacteria present have the genetic machinery to perform dissimilatory sulfate reduction, yet they have an acetogenic, hydrogenogenic way of life.In this review we evaluate the physiology and metabolic mode of SRB in relation with their environment.

  17. Chemical Synthesis of Sulfated Yeast (Saccharomyces cerevisiae) Glucans and Their In Vivo Antioxidant Activity.

    Science.gov (United States)

    Zhang, Hua; Zhang, Jing; Fan, Ziluan; Zhou, Xintao; Geng, Lin; Wang, Zhenyu; Regenstein, Joe M; Xia, Zhiqiang

    2017-07-28

    The effects of sulfation of yeast glucans was optimized using response surface methodology. The degree of sulfation was evaluated from 0.11 to 0.75 using ion-chromatography. The structural characteristics of SYG (sulfation of yeast glucans) with a DS = 0.75 were determined using high-performance liquid chromatography/gel-permeation chromatography and finally by Fourier transform infrared spectrometry. The SYG had lower viscosity and greater solubility than the native yeast glucans, suggesting that the conformation of the SYG had significantly changed. The results also showed that SYG had a significantly greater antioxidant activity in vivo compared to native yeast glucans.

  18. 2-Amino-4-hydroxyethylaminoanisole sulfate

    DEFF Research Database (Denmark)

    Madsen, Jakob T; Andersen, Klaus E

    2016-01-01

    positive patch test reactions to the coupler 2-amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014. METHODS: Patch test results from the Allergen Bank database for eczema patients patch tested with 2-amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014 were reviewed. RESULTS......: A total of 902 dermatitis patients (154 from the dermatology department and 748 from 65 practices) were patch tested with amino-4-hydroxyethylaminoanisole sulfate 2% pet. from 2005 to 2014. Thirteen (1.4%) patients had a positive patch test reaction. Our results do not indicate irritant reactions....... CONCLUSIONS: 2-Amino-4-hydroxyethylaminoanisole sulfate is a new but rare contact allergen....

  19. Proteomic Profiling of De Novo Protein Synthesis in Starvation-Induced Autophagy Using Bioorthogonal Noncanonical Amino Acid Tagging.

    Science.gov (United States)

    Zhang, J; Wang, J; Lee, Y-M; Lim, T-K; Lin, Q; Shen, H-M

    2017-01-01

    Autophagy is an intracellular degradation process activated by stress factors such as nutrient starvation to maintain cellular homeostasis. There is emerging evidence demonstrating that de novo protein synthesis is involved in the autophagic process. However, up-to-date characterizing of these de novo proteins is technically difficult. In this chapter, we describe a novel method to identify newly synthesized proteins during starvation-mediated autophagy by bioorthogonal noncanonical amino acid tagging (BONCAT), in conjunction with isobaric tagging for relative and absolute quantification (iTRAQ)-based quantitative proteomics. l-azidohomoalanine (AHA) is an analog of methionine, and it can be readily incorporated into the newly synthesized proteins. The AHA-containing proteins can be enriched with avidin beads after a "click" reaction between alkyne-bearing biotin and the azide moiety of AHA. The enriched proteins are then subjected to iTRAQ™ labeling for protein identification and quantification using liquid chromatography-tandem mass spectrometry (LC-MS/MS). By using this technique, we have successfully profiled more than 700 proteins that are synthesized during starvation-induced autophagy. We believe that this approach is effective in identification of newly synthesized proteins in the process of autophagy and provides useful insights to the molecular mechanisms and biological functions of autophagy. © 2017 Elsevier Inc. All rights reserved.

  20. Dying piece by piece: carbohydrate dynamics in aspen seedlings under severe carbon stress and starvation

    Science.gov (United States)

    Wiley, Erin; Chow, Pak; Landhäusser, Simon

    2016-04-01

    Carbon stress and starvation remain poorly understood in trees, despite their potential role in mortality from a variety of agents. To explore the effects of carbon stress on nonstructural carbohydrate (NSC) dynamics and recovery potential and to examine the process of starvation, we grew aspen seedlings under one of three levels of shade: 40% (light shade), 8% (medium shade), and 4% (dark shade) of full sunlight. We then exposed seedlings to 24 hours darkness at either 20° or 28° C until trees had died. Periodically, seedlings were harvested for NSC analysis and to measure stem and root respiration. In addition, some seedlings were moved back into the light to determine if recovery was possible at certain points during starvation. Specifically, we sought to address the following questions: 1) Do NSC concentrations or mass influence tree survival under carbon stress? 2) At what carbohydrate levels do trees fail to recover and starve? 3) Does temperature affect the NSC level at which trees starve? Increasing shade reduced growth, but surprisingly did not reduce NSC levels, except in a portion of deep shade seedlings that experienced dieback. Once in darkness, leaves died first, with final NSC levels ranging from ~4% (Medium shade, 28 degrees) to 7.5% (Light shade). Stem death generally occurred gradually down the stem. Stem tissues retained ~1-2% NSC when dead. Recovery was still possible when only the upper half of the stem had died; at this point, seedlings had relatively high root NSC levels in their remaining roots (7-10%), with 1-3% starch. No trees recovered after the whole stem had died, at which point, some trees root systems were completely dead. However, most retained substantial amounts of live roots, averaging 5-6% NSC, with 0.25-1.5% starch. Despite the initially similar NSC concentrations, light shade seedlings took longer to reach half stem and whole stem death than seedlings from medium and dark shade. Longer survival times were associated with

  1. HSV-1 interaction to 3-O-sulfated heparan sulfate in mouse-derived DRG explant and profiles of inflammatory markers during virus infection.

    Science.gov (United States)

    Sharthiya, Harsh; Seng, Chanmoly; Van Kuppevelt, T H; Tiwari, Vaibhav; Fornaro, Michele

    2017-06-01

    The molecular mechanism of herpes simplex virus (HSV) entry and the associated inflammatory response in the nervous system remain poorly understood. Using mouse-derived ex vivo dorsal root ganglia (DRG) explant model and single cell neurons (SCNs), in this study, we provided a visual evidence for the expression of heparan sulfate (HS) and 3-O-sulfated heparan sulfate (3-OS HS) followed by their interactions with HSV-1 glycoprotein B (gB) and glycoprotein D (gD) during cell entry. Upon heparanase treatment of DRG-derived SCN, a significant inhibition of HSV-1 entry was observed suggesting the involvement of HS role during viral entry. Finally, a cytokine array profile generated during HSV-1 infection in DRG explant indicated an enhanced expression of chemokines (LIX, TIMP-2, and M-CSF)-known regulators of HS. Taken together, these results highlight the significance of HS during HSV-1 entry in DRG explant. Further investigation is needed to understand which isoforms of 3-O-sulfotransferase (3-OST)-generated HS contributed during HSV-1 infection and associated cell damage.

  2. [Screening serum response special antibodies of U251 cell line from surface display phage antibody library].

    Science.gov (United States)

    Yu, Min; Tan, De-Yong; Qian, Wei; Lai, Jian-Hua; Sun, Gui-Lin

    2004-05-01

    U251 cell is a sensitive cell line to serum, which stops at G0 phase of cell cycle in no-serum medium, and recovers growth when the serum is added into no-serum medium. The cell can express corresponding proteins in different phase of cell cycle. Therefore it is very signification for the study of cell cycle regulation mechanism that explores these proteins. In this paper, the mouse antibody phage display library was added into the bottle in which the serum starvation U251 cells had been cultured, and the special antibody phages were absorbed. Then the absorbed antibody phages were amplified by adding E. coli TG1 and helper phage M13K07. Amplified antibody phages were added into bottle in which the serum cultured cell after serum starvation (follow named as serum recovered cells) were incubated, so that the cell absorbed the no-special antibody phages for the serum starvation cell and the special antibody phages were in supernatant. The remaining no-special antibody phages in the supernatant were discarded by repeating above program 3-4 times. The pure special antibody phages were gotten, and amplified by adding the host cell E. coli TG1 and helper phage M13K07. Then the host bacterium infected special antibody phage was spread on the plate medium with ampicillin, and the monoclonal antibody phages were gotten. Using same as above program, the monoclonal antibody phages absorbed specially for serum recovered U251 cells were obtained when the serum recovered cells instead of serum starvation cells and serum starvation cells instead of serum recovered cells. In this study, ninety-six positive monoclonal antibody phages that absorbed specially the serum starvation cells and eighty-two positive monoclonal antibody phages that absorbed specially the serum recovered cells were obtained. By using cell immunochemistry assay, two special signification antibodies were obtained. one (No.11) was the strong response in serum starvation cells, the other (No.2) was the strong

  3. A multi-analytical approach to better assess the keratan sulfate contamination in animal origin chondroitin sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Restaino, Odile Francesca, E-mail: odilefrancesca.restaino@unina2.it [Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania-L.Vanvitelli, ex Second University of Naples, Via De Crecchio 7, 80138, Naples (Italy); Finamore, Rosario, E-mail: rosario.finamore@unina2.it [Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania-L.Vanvitelli, ex Second University of Naples, Via De Crecchio 7, 80138, Naples (Italy); Diana, Paola, E-mail: paola.diana@unina2.it [Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania-L.Vanvitelli, ex Second University of Naples, Via De Crecchio 7, 80138, Naples (Italy); Marseglia, Mariacarmela, E-mail: marimars84@hotmail.it [Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania-L.Vanvitelli, ex Second University of Naples, Via De Crecchio 7, 80138, Naples (Italy); Vitiello, Mario, E-mail: mariovitiello.ita@gmail.com [Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania-L.Vanvitelli, ex Second University of Naples, Via De Crecchio 7, 80138, Naples (Italy); Casillo, Angela, E-mail: angela.casillo@unina.it [Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Naples (Italy); Bedini, Emiliano, E-mail: emiliano.bedini@unina.it [Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Naples (Italy); Parrilli, Michelangelo, E-mail: michelangelo.parrilli@unina.it [Department of Biology, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Naples (Italy); and others

    2017-03-15

    Chondroitin sulfate is a glycosaminoglycan widely used as active principle of anti-osteoarthritis drugs and nutraceuticals, manufactured by extraction from animal cartilaginous tissues. During the manufacturing procedures, another glycosaminoglycan, the keratan sulfate, might be contemporarily withdrawn, thus eventually constituting a contaminant difficult to be determined because of its structural similarity. Considering the strict regulatory rules on the pureness of pharmaceutical grade chondrotin sulfate there is an urgent need and interest to determine the residual keratan sulfate with specific, sensitive and reliable methods. To pursue this aim, in this paper, for the first time, we set up a multi-analytical and preparative approach based on: i) a newly developed method by high performance anion-exchange chromatography with pulsed amperometric detection, ii) gas chromatography-mass spectrometry analyses, iii) size exclusion chromatography analyses coupled with triple detector array module and on iv) strong anion exchange chromatography separation. Varied KS percentages, in the range from 0.1 to 19.0% (w/w), were determined in seven pharmacopeia and commercial standards and nine commercial samples of different animal origin and manufacturers. Strong anion exchange chromatography profiles of the samples showed three or four different peaks. These peaks analyzed by high performance anion-exchange with pulsed amperometric detection and size exclusion chromatography with triple detector array, ion chromatography and by mono- or two-dimensional nuclear magnetic resonance revealed a heterogeneous composition of both glycosaminoglycans in terms of sulfation grade and molecular weight. High molecular weight species (>100 KDa) were also present in the samples that counted for chains still partially linked to a proteoglycan core. - Highlights: • A multi-analytical approach was set up, for the first time, for the determination of the residual keratan sulfate

  4. A multi-analytical approach to better assess the keratan sulfate contamination in animal origin chondroitin sulfate

    International Nuclear Information System (INIS)

    Restaino, Odile Francesca; Finamore, Rosario; Diana, Paola; Marseglia, Mariacarmela; Vitiello, Mario; Casillo, Angela; Bedini, Emiliano; Parrilli, Michelangelo

    2017-01-01

    Chondroitin sulfate is a glycosaminoglycan widely used as active principle of anti-osteoarthritis drugs and nutraceuticals, manufactured by extraction from animal cartilaginous tissues. During the manufacturing procedures, another glycosaminoglycan, the keratan sulfate, might be contemporarily withdrawn, thus eventually constituting a contaminant difficult to be determined because of its structural similarity. Considering the strict regulatory rules on the pureness of pharmaceutical grade chondrotin sulfate there is an urgent need and interest to determine the residual keratan sulfate with specific, sensitive and reliable methods. To pursue this aim, in this paper, for the first time, we set up a multi-analytical and preparative approach based on: i) a newly developed method by high performance anion-exchange chromatography with pulsed amperometric detection, ii) gas chromatography-mass spectrometry analyses, iii) size exclusion chromatography analyses coupled with triple detector array module and on iv) strong anion exchange chromatography separation. Varied KS percentages, in the range from 0.1 to 19.0% (w/w), were determined in seven pharmacopeia and commercial standards and nine commercial samples of different animal origin and manufacturers. Strong anion exchange chromatography profiles of the samples showed three or four different peaks. These peaks analyzed by high performance anion-exchange with pulsed amperometric detection and size exclusion chromatography with triple detector array, ion chromatography and by mono- or two-dimensional nuclear magnetic resonance revealed a heterogeneous composition of both glycosaminoglycans in terms of sulfation grade and molecular weight. High molecular weight species (>100 KDa) were also present in the samples that counted for chains still partially linked to a proteoglycan core. - Highlights: • A multi-analytical approach was set up, for the first time, for the determination of the residual keratan sulfate

  5. Regulation of neuronal APL-1 expression by cholesterol starvation.

    Directory of Open Access Journals (Sweden)

    Mary Wiese

    Full Text Available BACKGROUND: Alzheimer's disease (AD is a neurodegenerative disorder characterized by the deposition of β-amyloid plaques composed primarily of the amyloid-β peptide, a cleavage product of amyloid precursor protein (APP. While mutations in APP lead to the development of Familial Alzheimer's Disease (FAD, sporadic AD has only one clear genetic modifier: the ε4 allele of the apolipoprotein E (ApoE gene. Cholesterol starvation in Caenorhabditis elegans leads to molting and arrest phenotypes similar to loss-of-function mutants of the APP ortholog, apl-1 (amyloid precursor-like protein 1, and lrp-1 (lipoprotein receptor-related protein 1, suggesting a potential interaction between apl-1 and cholesterol metabolism. METHODOLOGY/PRINCIPAL FINDINGS: Previously, we found that RNAi knock-down of apl-1 leads to aldicarb hypersensitivity, indicating a defect in synaptic function. Here we find the same defect is recapitulated during lrp-1 knock-down and by cholesterol starvation. A cholesterol-free diet or loss of lrp-1 directly affects APL-1 levels as both lead to loss of APL-1::GFP fluorescence in neurons. However, loss of cholesterol does not affect global transcription or protein levels as seen by qPCR and Western blot. CONCLUSIONS: Our results show that cholesterol and lrp-1 are involved in the regulation of synaptic transmission, similar to apl-1. Both are able to modulate APL-1 protein levels in neurons, however cholesterol changes do not affect global apl-1 transcription or APL-1 protein indicating the changes are specific to neurons. Thus, regulation of synaptic transmission and molting by LRP-1 and cholesterol may be mediated by their ability to control APL-1 neuronal protein expression.

  6. Metabolic niche of a prominent sulfate-reducing human gut bacterium.

    Science.gov (United States)

    Rey, Federico E; Gonzalez, Mark D; Cheng, Jiye; Wu, Meng; Ahern, Philip P; Gordon, Jeffrey I

    2013-08-13

    Sulfate-reducing bacteria (SRB) colonize the guts of ∼50% of humans. We used genome-wide transposon mutagenesis and insertion-site sequencing, RNA-Seq, plus mass spectrometry to characterize genetic and environmental factors that impact the niche of Desulfovibrio piger, the most common SRB in a surveyed cohort of healthy US adults. Gnotobiotic mice were colonized with an assemblage of sequenced human gut bacterial species with or without D. piger and fed diets with different levels and types of carbohydrates and sulfur sources. Diet was a major determinant of functions expressed by this artificial nine-member community and of the genes that impact D. piger fitness; the latter includes high- and low-affinity systems for using ammonia, a limiting resource for D. piger in mice consuming a polysaccharide-rich diet. Although genes involved in hydrogen consumption and sulfate reduction are necessary for its colonization, varying dietary-free sulfate levels did not significantly alter levels of D. piger, which can obtain sulfate from the host in part via cross-feeding mediated by Bacteroides-encoded sulfatases. Chondroitin sulfate, a common dietary supplement, increased D. piger and H2S levels without compromising gut barrier integrity. A chondroitin sulfate-supplemented diet together with D. piger impacted the assemblage's substrate utilization preferences, allowing consumption of more reduced carbon sources and increasing the abundance of the H2-producing Actinobacterium, Collinsella aerofaciens. Our findings provide genetic and metabolic details of how this H2-consuming SRB shapes the responses of a microbiota to diet ingredients and a framework for examining how individuals lacking D. piger differ from those who harbor it.

  7. Comparison of magnesium sulfate and sodium sulfate for removal of water from pesticide extracts of foods.

    Science.gov (United States)

    Schenck, Frank J; Callery, Patrick; Gannett, Peter M; Daft, Jonathan R; Lehotay, Steven J

    2002-01-01

    Water-miscible solvents, such as acetone and acetonitrile, effectively extract both polar and nonpolar pesticide residues from nonfatty foods. The addition of sodium chloride to the resulting acetonitrile-water or acetone-water extract (salting out) results in the separation of the water from the organic solvent. However, the organic solvent layer (pesticide extract) still contains some residual water, which can adversely affect separation procedures that follow, such as solid-phase extraction and/or gas chromatography. Drying agents, such as sodium sulfate or magnesium sulfate, are used to remove the water from the organic extracts. In the present study, we used nuclear magnetic resonance spectroscopy to study the composition of the phases resulting from salting out and to compare the effectiveness of sodium sulfate and magnesium sulfate as drying agents. The study showed that considerable amounts of water remained in the organic phase after phase separation. Sodium sulfate was a relatively ineffective drying agent, removing little or no residual water from the organic solvent. Magnesium sulfate proved to be a much more effective drying agent.

  8. Sulfate-driven elemental sparing is regulated at the transcriptional and posttranscriptional levels in a filamentous cyanobacterium.

    Science.gov (United States)

    Gutu, Andrian; Alvey, Richard M; Bashour, Sami; Zingg, Daniel; Kehoe, David M

    2011-03-01

    Sulfur is an essential nutrient that can exist at growth-limiting concentrations in freshwater environments. The freshwater cyanobacterium Fremyella diplosiphon (also known as Tolypothrix sp. PCC 7601) is capable of remodeling the composition of its light-harvesting antennae, or phycobilisomes, in response to changes in the sulfur levels in its environment. Depletion of sulfur causes these cells to cease the accumulation of two forms of a major phycobilisome protein called phycocyanin and initiate the production of a third form of phycocyanin, which possesses a minimal number of sulfur-containing amino acids. Since phycobilisomes make up approximately 50% of the total protein in these cells, this elemental sparing response has the potential to significantly influence the fitness of this species under low-sulfur conditions. This response is specific for sulfate and occurs over the physiological range of sulfate concentrations likely to be encountered by this organism in its natural environment. F. diplosiphon has two separate sulfur deprivation responses, with low sulfate levels activating the phycobilisome remodeling response and low sulfur levels activating the chlorosis or bleaching response. The phycobilisome remodeling response results from changes in RNA abundance that are regulated at both the transcriptional and posttranscriptional levels. The potential of this response, and the more general bleaching response of cyanobacteria, to provide sulfur-containing amino acids during periods of sulfur deprivation is examined.

  9. Modeling of sulfation of potassium chloride by ferric sulfate addition during grate-firing of biomass

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Aho, Martti

    2013-01-01

    Potassium chloride, KCl, formed from critical ash-forming elements released during combustion may lead to severe ash deposition and corrosion problems in biomass-fired boilers. Ferric sulfate, Fe2(SO4)3 is an effective additive, which produces sulfur oxides (SO2 and SO3) to convert KCl to the less...... harmful K2SO4. In the present study the decomposition of ferric sulfate is studied in a fast-heating rate thermogravimetric analyzer (TGA), and a kinetic model is proposed to describe the decomposition process. The yields of SO2 and SO3 from ferric sulfate decomposition are investigated in a laboratory......-scale tube reactor. It is revealed that approximately 40% of the sulfur is released as SO3, the remaining fraction being released as SO2. The proposed decomposition model of ferric sulfate is combined with a detailed gas phase kinetic model of KCl sulfation, and a simplified model of K2SO4 condensation...

  10. Adaptive Roles of SSY1 and SIR3 During Cycles of Growth and Starvation in Saccharomyces cerevisiae Populations Enriched for Quiescent or Nonquiescent Cells.

    Science.gov (United States)

    Wloch-Salamon, Dominika M; Tomala, Katarzyna; Aggeli, Dimitra; Dunn, Barbara

    2017-06-07

    Over its evolutionary history, Saccharomyces cerevisiae has evolved to be well-adapted to fluctuating nutrient availability. In the presence of sufficient nutrients, yeast cells continue to proliferate, but upon starvation haploid yeast cells enter stationary phase and differentiate into nonquiescent (NQ) and quiescent (Q) cells. Q cells survive stress better than NQ cells and show greater viability when nutrient-rich conditions are restored. To investigate the genes that may be involved in the differentiation of Q and NQ cells, we serially propagated yeast populations that were enriched for either only Q or only NQ cell types over many repeated growth-starvation cycles. After 30 cycles (equivalent to 300 generations), each enriched population produced a higher proportion of the enriched cell type compared to the starting population, suggestive of adaptive change. We also observed differences in each population's fitness suggesting possible tradeoffs: clones from NQ lines were better adapted to logarithmic growth, while clones from Q lines were better adapted to starvation. Whole-genome sequencing of clones from Q- and NQ-enriched lines revealed mutations in genes involved in the stress response and survival in limiting nutrients ( ECM21 , RSP5 , MSN1 , SIR4 , and IRA2 ) in both Q and NQ lines, but also differences between the two lines: NQ line clones had recurrent independent mutations affecting the Ssy1p-Ptr3p-Ssy5p (SPS) amino acid sensing pathway, while Q line clones had recurrent, independent mutations in SIR3 and FAS1 Our results suggest that both sets of enriched-cell type lines responded to common, as well as distinct, selective pressures. Copyright © 2017 Wloch-Salamon et al.

  11. Vaginal Heparan Sulfate Linked to Neutrophil Dysfunction in the Acute Inflammatory Response Associated with Experimental Vulvovaginal Candidiasis.

    Science.gov (United States)

    Yano, Junko; Noverr, Mairi C; Fidel, Paul L

    2017-03-14

    worldwide. Despite an acute inflammatory response by neutrophils during infection, the response fails to reduce the organism. Instead, the response is considered a key process underlying the symptoms of vaginitis. Therefore, it is important to determine the mechanism(s) associated with the lack of vaginal neutrophil antifungal activity. The established mouse model of Candida vaginitis was used to uncover the mechanism of neutrophil dysfunction. Results revealed that heparan sulfate present in the vagina of mice susceptible to chronic vaginitis served as a competitive ligand for the receptor (Mac-1) necessary for fungal recognition and neutrophil-mediated killing. This inhibitory function of heparan sulfate, confirmed through several approaches, provides the first evidence to explain the lack of antifungal immune reactivity during vaginal candidiasis. This finding paves the way for design of therapeutic strategies to reduce/eliminate symptomatic vaginal candidiasis and restore quality of life to those affected. Copyright © 2017 Yano et al.

  12. Bactericide for sulfate-reducing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Shklyar, T F; Anoshina, G M; Blokhin, V Ye; Kisarrev, Ye L; Novikovsa, G M

    1981-01-01

    The aim of the invention is to find a bactericide for sulfate-reducing bacteria of oil fields in Western Siberia in order to suppress the biocorrosive activity on oil industry equipment. This goal is achieved by using M-nitroacetanylide as the bactericide of sulfate-reducing bacteria. This agent suppresses the activity of a stored culture of sulfate-reducing bacteria that comes from industrial waste waters injection wells of the Smotlor oil field.

  13. Adsorption of water, sulfates and chloride on arsenopyrite surface

    Science.gov (United States)

    Silva, Juliana C. M.; dos Santos, Egon C.; de Oliveira, Aline; Heine, Thomas; De Abreu, Heitor A.; Duarte, Hélio A.

    2018-03-01

    Arsenopyrite is one of the sulfide minerals responsible for acid rock drainage (ARD) and is one of the most hazardous in regions affected by mining activities. This phenomenon involves complex reaction mechanism. Although it is intensely investigated, there is a lack of consensus concerning the reaction mechanisms and more information is still necessary. In this work, the adsorption of water, hydrochloric acid, and sulfuric acid on arsenopyrite (001) surface was investigated by means of Density Functional calculations and the results compared to other sulfides aiming to understand the mineral/water interface. The interaction of the chemical species with the (001) FeAsS surface is the first step to understand the intricate oxidation mechanism of arsenopyrite. Molecular water adsorption on (001) FeAsS is more favored than the adsorption of sulfate favoring the dissolution of sulfates and enhancing its oxidation. The estimated adsorption energies of water, sulfates and chloride on other sulfide minerals are compared with the estimated values for arsenopyrite and the chemical reactivity differences discussed in detail.

  14. Inter vs. intraglycosidic acetal linkages control sulfation pattern in semi-synthetic chondroitin sulfate.

    Science.gov (United States)

    Laezza, Antonio; De Castro, Cristina; Parrilli, Michelangelo; Bedini, Emiliano

    2014-11-04

    Microbial-sourced unsulfated chondroitin could be converted into chondroitin sulfate (CS) polysaccharide by a multi-step strategy relying upon benzylidenation and acetylation reactions as key-steps for its regioselective protection. By conducting the two reactions one- or two-pots, CSs with different sulfation patterns could be obtained at the end of the semi-synthesis. In particular, a CS polysaccharide possessing sulfate groups randomly distributed between positions 4 and 6 of N-acetyl-galactosamine (GalNAc) units could be obtained through the two-pots route, whereas the one-pot pathway allowed an additional sulfation at position 3 of some glucuronic acid (GlcA) units. This difference was ascribed to the stabilization of a labile interglycosidic benzylidene acetal involving positions O-3 and O-6 of some GlcA and GalNAc, respectively, when the benzylidene-acetylation reactions were conducted in a one-pot fashion. Isolation and characterization of a polysaccharide intermediate showing interglycosidic acetal moieties was accomplished. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Studies on insulin receptor, 2. Studies on the influence of starvation and high fat diet on insulin receptor

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Y [Hiroshima Univ. (Japan). School of Medicine

    1979-08-01

    The present study is to investigate an influence of starvation and high fat diet on insulin receptor of the plasma membrane by means of radioreceptor assay using /sup 125/I-labelled insulin. Male guinea pigs of Hartley strain were employed for the starvation study, and /sup 125/I-insulin binding capacity on the plasma membrane of the liver and kidney was determined at 24, 48 and 72 hours of the fast after the last meal. Male rats of Wistar strain were employed for the high fat study where the diet containing 35% of butter was fed ad libitum for 38 or 68 days. The animals were killed at the fast of 12 hours, and /sup 125/I-insulin binding capacity on the plasma membrane of the liver was determined. The results obtained are summarized as follows: 1) An increase in /sup 125/I-insulin binding capacity on the plasma membrane of the liver and kidney was observed by the starvation for 24 to 72 hours. 2) The mechanism of the increase by starvation was considered to be different by the organs; it was due to an increase in number of insulin receptor in the liver, and due to an increase in affinity of insulin receptor in the kidney. 3) In non-obese rats fed with high fat diet, the number of insulin receptor on the liver plasma membrane showed a decrease, and this observation clearly indicated that the decrease in number of the receptor did not depend on the obesity. 4) Obese rats also fed with high fat diet presented a decrease in number of insulin receptor without an elevation of insulin levels in the circulating blood. This indicated that at least in the obese rats fed with high fat diet, the decrease in number of the receptor was not due to hyperinsulinemia.

  16. 21 CFR 582.5443 - Magnesium sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium sulfate. 582.5443 Section 582.5443 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5443 Magnesium sulfate. (a) Product. Magnesium sulfate. (b) Conditions of use. This...

  17. 21 CFR 582.5230 - Calcium sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium sulfate. 582.5230 Section 582.5230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5230 Calcium sulfate. (a) Product. Calcium sulfate. (b) Conditions of use. This substance...

  18. 21 CFR 582.1125 - Aluminum sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Aluminum sulfate. 582.1125 Section 582.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1125 Aluminum sulfate. (a) Product. Aluminum sulfate. (b) Conditions of use. This substance...

  19. 21 CFR 182.1125 - Aluminum sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Aluminum sulfate. 182.1125 Section 182.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1125 Aluminum sulfate. (a) Product. Aluminum sulfate. (b) Conditions of use. This substance...

  20. Sulfation pattern of fucose branches affects the anti-hyperlipidemic activities of fucosylated chondroitin sulfate.

    Science.gov (United States)

    Wu, Nian; Zhang, Yu; Ye, Xingqian; Hu, Yaqin; Ding, Tian; Chen, Shiguo

    2016-08-20

    Fucosylated chondroitin sulfates (fCSs) are glycosaminoglycans extracted from sea cucumbers, consisting of chondroitin sulfate E (CSE) backbones and sulfated fucose branches. The biological properties of fCSs could be affected by the sulfation pattern of their fucose branches. In the present study, two fCSs were isolated from sea cucumbers Isostichopus badionotus (fCS-Ib) and Pearsonothuria graeffei (fCS-Pg). Their monosaccharide compositions of glucuronic acid (GlcA), N-acetylgalactosamine (GalNAc), fucose (Fuc) and sulfate were at similar molar ratio with 1.0/0.7/0.9/3.1 for fCS-Ib and 1.0/0.8/1.5/2.6 for fCS-Pg. The two fCSs have different sulfation patterns on their fucose branches, fCS-Pg with 3,4-O-disulfation while fCS-Ib with 2,4-O-disulfation. Their antihyperlipidemic effects were compared using a high-fat high-fructose diet (HFFD)-fed C57BL/6J mice model. Both fCS-Ib and fCS-Pg had significant effects on lipid profile improvement, liver protection, blood glucose diminution and hepatic glycogen synthesis. Specifically, fCS-Pg with 3,4-O-disulfation fucose branches was more effective in reduction of blood cholesterol (TC), low density lipoprotein (LDL) and atherogenic index (AI). Our results indicate that both fCSs, especially fCS-Pg, could be used as a potential anti-hyperlipidemic drug. Copyright © 2016. Published by Elsevier Ltd.

  1. Progesterone production requires activation of caspase-3 in preovulatory granulosa cells in a serum starvation model.

    Science.gov (United States)

    An, Li-Sha; Yuan, Xiao-Hua; Hu, Ying; Shi, Zi-Yun; Liu, Xiao-Qin; Qin, Li; Wu, Gui-Qing; Han, Wei; Wang, Ya-Qin; Ma, Xu

    2012-11-01

    Granulosa cells proliferate, differentiate, and undergo apoptosis throughout follicular development. Previous studies have demonstrated that stimulation of progesterone production is accompanied by caspase-3 activation. Moreover, we previously reported that arsenic enhanced caspase-3 activity coupled with progesterone production. Inhibition of caspase-3 activity can significantly inhibit progesterone production induced by arsenic or follicle-stimulating hormone (FSH). Here, we report that serum starvation induces caspase-3 activation coupled with augmentation of progesterone production. Serum starvation also increased the levels of cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) and steroidogenic acute regulatory (StAR) protein, both of which may contribute to progesterone synthesis in preovulatory granulosa cells. Inhibition of caspase-3 activity resulted in a decrease in progesterone production. Deactivation of caspase-3 activity by caspase-3 specific inhibitor also resulted in decreases in P450scc and StAR expression, which may partly contribute to the observed decrease in progesterone production. Our study demonstrates for the first time that progesterone production in preovulatory granulosa cells is required for caspase-3 activation in a serum starvation model. Inhibition of caspase-3 activity can result in decreased expression of the steroidogenic proteins P450scc and StAR. Our work provides further details on the relationship between caspase-3 activation and steroidogenesis and indicates that caspase-3 plays a critical role in progesterone production by granulosa cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Effect of Nitrogen Starvation on Desiccation Tolerance of Arctic Microcoleus Strains (Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Daria eTashyreva

    2015-04-01

    Full Text Available Although desiccation tolerance of Microcoleus species is a well-known phenomenon, there is very little information about their limits of desiccation tolerance in terms of cellular water content, the survival rate of their cells, and the environmental factors inducing their resistance to drying. We have discovered that three Microcoleus strains, isolated from terrestrial habitats of the High Arctic, survived extensive dehydration (to 0.23 g water g-1 dry mass, but did not tolerate complete desiccation (to 0.03 g water g-1 dry mass regardless of pre-desiccation treatments. However, these treatments were critical for the survival of incomplete desiccation: cultures grown under optimal conditions failed to survive even incomplete desiccation; a low temperature enabled only 0 to 15% of cells to survive, while 39.8 to 65.9% of cells remained alive and intact after nitrogen starvation. Unlike Nostoc, which co-exists with Microcoleus in Arctic terrestrial habitats, Microcoleus strains are not truly anhydrobiotic and do not possess constitutive desiccation tolerance. Instead, it seems that the survival strategy of Microcoleus in periodically dry habitats involves avoidance of complete desiccation, but tolerance to milder desiccation stress, which is induced by suboptimal conditions (e.g. nitrogen starvation.

  3. Transcriptome Analysis of Two Rice Varieties Contrasting for Nitrogen Use Efficiency under Chronic N Starvation Reveals Differences in Chloroplast and Starch Metabolism-Related Genes

    Directory of Open Access Journals (Sweden)

    Subodh Kumar Sinha

    2018-04-01

    Full Text Available The nitrogen use efficiency (NUE of crop plants is limited and enhancing it in rice, a major cereal crop, would be beneficial for farmers and the environment alike. Here we report the genome-wide transcriptome analysis of two rice genotypes, IR 64 (IR64 and Nagina 22 (N22 under optimal (+N and chronic starvation (-N of nitrogen (N from 15-day-old root and shoot tissues. The two genotypes were found to be contrasting in their response to -N; IR64 root architecture and root dry weight remained almost equivalent to that under +N conditions, while N22 showed high foraging ability but a substantial reduction in biomass under -N. Similarly, the photosynthetic pigments showed a drastic reduction in N22 under low N, while IR64 was more resilient. Nitrate reductase showed significantly low specific activity under -N in both genotypes. Glutamate synthase (GOGAT and citrate synthase CS activity were highly reduced in N22 but not in IR64. Transcriptome analysis of these genotypes revealed nearly double the number of genes to be differentially expressed (DEGs in roots (1016 compared to shoots (571. The response of the two genotypes to N starvation was distinctly different reflecting their morphological/biochemical response with just two and eight common DEGs in the root and shoot tissues. There were a total of 385 nitrogen-responsive DEGs (106 in shoots and 279 in roots between the two genotypes. Fifty-two of the 89 DEGs identified as specific to N22 root tissues were also found to be differentially expressed between the two genotypes under -N. Most of these DEGs belonged to starch and chloroplast metabolism, followed by membrane and signaling proteins. Physical mapping of DEGs revealed 95 DEGs in roots and 76 in shoots to be present in quantitative trait loci (QTL known for NUE.

  4. Key factors influencing rates of heterotrophic sulfate reduction in active seafloor hydrothermal massive sulfide deposits

    Directory of Open Access Journals (Sweden)

    Kiana Laieikawai Frank

    2015-12-01

    Full Text Available Hydrothermal vents are thermally and geochemically dynamic habitats, and the organisms therein are subject to steep gradients in temperature and chemistry. To date, the influence of these environmental dynamics on microbial sulfate reduction has not been well constrained. Here, via multivariate experiments, we evaluate the effects of key environmental variables (temperature, pH, H2S, SO42-, DOC on sulfate reduction rates and metabolic energy yields in material recovered from a hydrothermal flange from the Grotto edifice in the Main Endeavor Field, Juan de Fuca Ridge. Sulfate reduction was measured in batch reactions across a range of physico-chemical conditions. Temperature and pH were the strongest stimuli, and maximum sulfate reduction rates were observed at 50 °C and pH 6, suggesting that the in situ community of sulfate-reducing organisms in Grotto flanges may be most active in a slightly acidic and moderate thermal/chemical regime. At pH 4, sulfate reduction rates increased with sulfide concentrations most likely due to the mitigation of metal toxicity. While substrate concentrations also influenced sulfate reduction rates, energy-rich conditions muted the effect of metabolic energetics on sulfate reduction rates. We posit that variability in sulfate reduction rates reflect the response of the active microbial consortia to environmental constraints on in situ microbial physiology, toxicity, and the type and extent of energy limitation. These experiments help to constrain models of the spatial contribution of heterotrophic sulfate reduction within the complex gradients inherent to seafloor hydrothermal deposits.

  5. 21 CFR 524.1484e - Neomycin sulfate and polymyxin B sulfate ophthalmic solution.

    Science.gov (United States)

    2010-04-01

    ... ophthalmic solution. 524.1484e Section 524.1484e Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.1484e Neomycin sulfate and polymyxin B sulfate ophthalmic solution. (a...

  6. Reduction of metal artifacts: beam hardening and photon starvation effects

    Science.gov (United States)

    Yadava, Girijesh K.; Pal, Debashish; Hsieh, Jiang

    2014-03-01

    The presence of metal-artifacts in CT imaging can obscure relevant anatomy and interfere with disease diagnosis. The cause and occurrence of metal-artifacts are primarily due to beam hardening, scatter, partial volume and photon starvation; however, the contribution to the artifacts from each of them depends on the type of hardware. A comparison of CT images obtained with different metallic hardware in various applications, along with acquisition and reconstruction parameters, helps understand methods for reducing or overcoming such artifacts. In this work, a metal beam hardening correction (BHC) and a projection-completion based metal artifact reduction (MAR) algorithms were developed, and applied on phantom and clinical CT scans with various metallic implants. Stainless-steel and Titanium were used to model and correct for metal beam hardening effect. In the MAR algorithm, the corrupted projection samples are replaced by the combination of original projections and in-painted data obtained by forward projecting a prior image. The data included spine fixation screws, hip-implants, dental-filling, and body extremity fixations, covering range of clinically used metal implants. Comparison of BHC and MAR on different metallic implants was used to characterize dominant source of the artifacts, and conceivable methods to overcome those. Results of the study indicate that beam hardening could be a dominant source of artifact in many spine and extremity fixations, whereas dental and hip implants could be dominant source of photon starvation. The BHC algorithm could significantly improve image quality in CT scans with metallic screws, whereas MAR algorithm could alleviate artifacts in hip-implants and dentalfillings.

  7. Galactose 6-sulfate sulfatase activity in Morquio syndrome

    International Nuclear Information System (INIS)

    Yutaka, T.; Okada, S.; Kato, T.; Inui, K.; Yabuuhi, H.

    1982-01-01

    The authors have prepared a new substrate, o-β-D-sulfo-galactosyl-(1-4)-β-D-6-sulfo-2-acetamido-2-deoxyglucosyl-(1-4)-D-[1- 3 H]galactitol, from shark cartilage keratan sulfate, for the assay of galactose 6-sulfate sulfatase activity. Using this substrate, they found there was a striking deficiency of galactose 6-sulfate sulfatase activity, in addition to the known deficiency of N-acetylgalactosamine 6-sulfate sulfatase, in the cultured skin fibroblasts of patients with Morquio syndrome. Their results could be explained by the hypothesis that accumulation of keratan sulfate and chondroitin 6-sulfate in Morquio syndrome is due to a deficiency of galactose 6-sulfate sulfatase and N-acetylgalactosamine 6-sulfate sulfatase activity, which are necessary for the degradation of these two mucopolysaccharides. (Auth.)

  8. Galactose 6-sulfate sulfatase activity in Morquio syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Yutaka, T.; Okada, S.; Kato, T.; Inui, K.; Yabuuhi, H. (Osaka Univ. (Japan). Faculty of Medicine)

    1982-07-01

    The authors have prepared a new substrate, o-..beta..-D-sulfo-galactosyl-(1-4)-..beta..-D-6-sulfo-2-acetamido-2-deoxyglucosyl-(1-4)-D-(1-/sup 3/H)galactitol, from shark cartilage keratan sulfate, for the assay of galactose 6-sulfate sulfatase activity. Using this substrate, they found there was a striking deficiency of galactose 6-sulfate sulfatase activity, in addition to the known deficiency of N-acetylgalactosamine 6-sulfate sulfatase, in the cultured skin fibroblasts of patients with Morquio syndrome. Their results could be explained by the hypothesis that accumulation of keratan sulfate and chondroitin 6-sulfate in Morquio syndrome is due to a deficiency of galactose 6-sulfate sulfatase and N-acetylgalactosamine 6-sulfate sulfatase activity, which are necessary for the degradation of these two mucopolysaccharides.

  9. The neurosteroid pregnenolone sulfate neutralized the learning impairment induced by intrahippocampal nicotine in alcohol-drinking rats.

    Science.gov (United States)

    Martín-García, E; Pallarès, M

    2005-01-01

    The effects of intrahippocampal administration of nicotine and the neurosteroids pregnenolone sulfate and allopregnanolone on acquiring the lever-press response and extinction in a Skinner box were examined using voluntary alcohol-drinking rats. A free-choice drinking procedure that implies early availability of the alcoholic solution (10% ethanol v/v+3% glucose w/v in distilled water) was used. Alcohol and control rats were deprived of food and assigned at random to six groups. Each group received two consecutive intrahippocampal (dorsal CA1) injections immediately after 1-h of drinking ethanol and before the free lever-press response shaping and extinction session. The groups were: saline-saline; saline-pregnenolone sulfate (5 ng, 24 microM); saline-allopregnanolone (0.2 microg, 1.26 microM); nicotine (4.6 microg, 20 mM)-saline; nicotine-pregnenolone sulfate; nicotine-allopregnanolone. Blood alcohol concentrations were assessed the day before conditioning. The combination of the oral self-administration of ethanol and the intrahippocampal injection of nicotine deteriorated the ability to acquire the lever-press response. This effect was neutralized by intrahippocampal pregnenolone sulfate (negative modulator of the GABA(A) receptor complex), and it was not affected by intrahippocampal allopregnanolone (positive GABA receptor complex A modulator). Pregnenolone sulfate and allopregnanolone had no effects per se on lever-press acquisition, neither in alcohol-drinking rats nor in controls. Alcohol consumption facilitated operant extinction just as anxiolytics that act as positive modulators of the GABA receptor complex A receptors do, possibly reducing the anxiety or aversion related to non-reinforcement. This effect was increased by intrahippocampal nicotine.

  10. 21 CFR 184.1643 - Potassium sulfate.

    Science.gov (United States)

    2010-04-01

    ... hydroxide or potassium carbonate. (b) The ingredient meets the specifications of the “Food Chemicals Codex... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium sulfate. 184.1643 Section 184.1643 Food... Specific Substances Affirmed as GRAS § 184.1643 Potassium sulfate. (a) Potassium sulfate (K2SO4, CAS Reg...

  11. Hydrometallurgical process for recovering iron sulfate and zinc sulfate from baghouse dust

    Science.gov (United States)

    Zaromb, Solomon; Lawson, Daniel B.

    1994-01-01

    A process for recovering zinc/rich and iron-rich fractions from the baghouse dust that is generated in various metallurgical operations, especially in steel-making and other iron-making plants, comprises the steps of leaching the dust by hot concentrated sulfuric acid so as to generate dissolved zinc sulfate and a precipitate of iron sulfate, separating the precipitate from the acid by filtration and washing with a volatile liquid, such as methanol or acetone, and collecting the filtered acid and the washings into a filtrate fraction. The volatile liquid may be recovered distillation, and the zinc may be removed from the filtrate by alternative methods, one of which involves addition of a sufficient amount of water to precipitate hydrated zinc sulfate at 10.degree. C., separation of the precipitate from sulfuric acid by filtration, and evaporation of water to regenerate concentrated sulfuric acid. The recovery of iron may also be effected in alternative ways, one of which involves roasting the ferric sulfate to yield ferric oxide and sulfur trioxide, which can be reconverted to concentrated sulfuric acid by hydration. The overall process should not generate any significant waste stream.

  12. The ceric sulfate dosimeter

    DEFF Research Database (Denmark)

    Bjergbakke, Erling

    1970-01-01

    The process employed for the determination of absorbed dose is the reduction of ceric ions to cerous ions in a solution of ceric sulfate and cerous sulfate in 0.8N sulfuric acid: Ce4+→Ce 3+ The absorbed dose is derived from the difference in ceric ion concentration before and after irradiation...

  13. Distinctive Oxidative Stress Responses to Hydrogen Peroxide in Sulfate Reducing Bacteria Desulfovibrio vulgaris Hildenborough

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Aifen; He, Zhili; Redding, A.M.; Mukhopadhyay, Aindrila; Hemme, Christopher L.; Joachimiak, Marcin P.; Bender, Kelly S.; Keasling, Jay D.; Stahl, David A.; Fields, Matthew W.; Hazen, Terry C.; Arkin, Adam P.; Wall, Judy D.; Zhou, Jizhong

    2009-01-01

    Response of Desulfovibrio vulgaris Hildenborough to hydrogen peroxide (H2O2, 1 mM) was investigated with transcriptomic, proteomic and genetic approaches. Microarray data demonstrated that gene expression was extensively affected by H2O2 with the response peaking at 120 min after H2O2 treatment. Genes affected include those involved with energy production, sulfate reduction, ribosomal structure and translation, H2O2 scavenging, posttranslational modification and DNA repair as evidenced by gene coexpression networks generated via a random matrix-theory based approach. Data from this study support the hypothesis that both PerR and Fur play important roles in H2O2-induced oxidative stress response. First, both PerR and Fur regulon genes were significantly up-regulated. Second, predicted PerR regulon genes ahpC and rbr2 were derepressedin Delta PerR and Delta Fur mutants and induction of neither gene was observed in both Delta PerR and Delta Fur when challenged with peroxide, suggesting possible overlap of these regulons. Third, both Delta PerR and Delta Fur appeared to be more tolerant of H2O2 as measured by optical density. Forth, proteomics data suggested de-repression of Fur during the oxidative stress response. In terms of the intracellular enzymatic H2O2 scavenging, gene expression data suggested that Rdl and Rbr2 may play major roles in the detoxification of H2O2. In addition, induction of thioredoxin reductase and thioredoxin appeared to be independent of PerR and Fur. Considering all data together, D. vulgaris employed a distinctive stress resistance mechanism to defend against increased cellular H2O2, and the temporal gene expression changes were consistent with the slowdown of cell growth at the onset of oxidative stress.

  14. Long-term experience with sodium chondroitin sulfate in patients with painful bladder syndrome.

    Science.gov (United States)

    Tornero, J I; Olarte, H; Escudero, F; Gómez, G

    2013-09-01

    To assess the response of patients diagnosed with painful bladder syndrome to treatment with instillations of sodium chondroitin sulfate. We present a series of cases of patients with painful bladder syndrome who followed a bladder instillation protocol with sodium chondroitin sulfate, according to our centre's regimen. The response to treatment was assessed with respect to pain, according to the Downie scale; urinary frequency, according to the voiding diary; and subjective improvement, according to the Patient Global Impression of Improvement (PGI-I) scale. A total of 28 patients with a median age of 59 years (range 22-90) followed this protocol. From the medical histories, 19.4% had suffered an infection of the urinary tract, 3.8% had suffered urinary tuberculosis, 7.6% received pelvic radiation therapy and 26.9% had taken anticholinergic drugs for overactive bladder syndrome. We evaluated the response to treatment at 0, 3, 6 and 12 months and found that at the end of treatment 72.3% of the patients had improved bladder pain and 75% were significantly better. Treatment with sodium chondroitin sulfate through endovesical instillation in painful bladder syndrome improves pain, voiding frequency and quality of life in the long term. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

  15. Resistance to starvation of Rhodnius neivai Lent, 1953 (Hemiptera: Reduviidae: Triatominae under experimental conditions

    Directory of Open Access Journals (Sweden)

    Daniel R Cabello

    2001-05-01

    Full Text Available The period of resistance to starvation and the loss of weight until death of Rhodnius neivai in all stages of development were studied. Work was based on experiments conducted under controlled laboratory conditions. One hundred specimens of each nymphal instar were observed: 50 were fed on chicken and 50 on rabbit. Adult females and males were kept together and fed on each host. All bugs were weighed weekly until death. Laid eggs were collected weekly and observed during five weeks to obtain hatchability. Resistance to starvation was similar with both hosts and increased with the evolutionary stage, excepting the 5th nymphal instar and adults. With both hosts, loss of weight was abrupt in the first week and steady in the following weeks. In adults, on the first weeks after eating, there was little or no mortality, after which mortality increased rapidly with the starving time. Reproductive output was higher in the bugs fed on rabbit. R. neivai is among the least resistant triatomine species.

  16. 21 CFR 184.1443 - Magnesium sulfate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium sulfate. 184.1443 Section 184.1443 Food... Specific Substances Affirmed as GRAS § 184.1443 Magnesium sulfate. (a) Magnesium sulfate (MgSO4·7H2O, CAS... magnesium oxide, hydroxide, or carbonate with sulfuric acid and evaporating the solution to crystallization...

  17. Magnesium sulfate differentially modulates fetal membrane inflammation in a time-dependent manner.

    Science.gov (United States)

    Cross, Sarah N; Nelson, Rachel A; Potter, Julie A; Norwitz, Errol R; Abrahams, Vikki M

    2018-04-30

    Chorioamnionitis and infection-associated inflammation are major causes of preterm birth. Magnesium sulfate (MgSO 4 ) is widely used in obstetrics as a tocolytic; however, its mechanism of action is unclear. This study sought to investigate how MgSO 4 modulates infection-associated inflammation in fetal membranes (FMs), and whether the response was time dependent. Human FM explants were treated with or without bacterial lipopolysaccharide (LPS); with or without MgSO 4 added either: 1 hour before LPS; at the same time as LPS; 1 hour post-LPS; or 2 hours post-LPS. Explants were also treated with or without viral dsRNA and LPS, alone or in combination; and MgSO 4 added 1 hour post-LPS After 24 hours, supernatants were measured for cytokines/chemokines; and tissue lysates measured for caspase-1 activity. Lipopolysaccharide-induced FM inflammation by upregulating the secretion of a number of inflammatory cytokines/chemokines. Magnesium sulfate administered 1-hour post-LPS inhibited FM secretion of IL-1β, IL-6, G-CSF, RANTES, and TNFα. Magnesium sulfate administered 2 hours post-LPS augmented FM secretion of these factors as well as IL-8, IFNγ, VEGF, GROα and IP-10. Magnesium sulfate delivered 1- hour post-LPS inhibited LPS-induced caspase-1 activity, and inhibited the augmented IL-1β response triggered by combination viral dsRNA and LPS. Magnesium sulfate differentially modulates LPS-induced FM inflammation in a time-dependent manner, in part through its modulation of caspase-1 activity. Thus, the timing of MgSO 4 administration may be critical in optimizing its anti-inflammatory effects in the clinical setting. MgSO 4 might also be useful at preventing FM inflammation triggered by a polymicrobial viral-bacterial infection. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Regeneration of sulfated metal oxides and carbonates

    Science.gov (United States)

    Hubble, Bill R.; Siegel, Stanley; Cunningham, Paul T.

    1978-03-28

    Alkali metal or alkaline earth metal carbonates such as calcium carbonate and magnesium carbonate found in dolomite or limestone are employed for removal of sulfur dioxide from combustion exhaust gases. The sulfated carbonates are regenerated to oxides through use of a solid-solid reaction, particularly calcium sulfide with calcium sulfate to form calcium oxide and sulfur dioxide gas. The regeneration is performed by contacting the sulfated material with a reductant gas such as hydrogen within an inert diluent to produce calcium sulfide in mixture with the sulfate under process conditions selected to permit the sulfide-sulfate, solid-state reaction to occur.

  19. Chondroitin 6-O-sulfate ameliorates experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Miyamoto, Katsuichi; Tanaka, Noriko; Moriguchi, Kota; Ueno, Rino; Kadomatsu, Kenji; Kitagawa, Hiroshi; Kusunoki, Susumu

    2014-05-01

    Chondroitin sulfate proteoglycans (CSPGs) are the main component of the extracellular matrix in the central nervous system (CNS) and influence neuroplasticity. Although CSPG is considered an inhibitory factor for nerve repair in spinal cord injury, it is unclear whether CSPG influences the pathogenetic mechanisms of neuroimmunological diseases. We induced experimental autoimmune encephalomyelitis (EAE) in chondroitin 6-O-sulfate transferase 1-deficient (C6st1(-/-)) mice. C6ST1 is the enzyme that transfers sulfate residues to position 6 of N-acetylgalactosamine in the sugar chain of CSPG. The phenotypes of EAE in C6st1(-/-) mice were more severe than those in wild-type (WT) mice were. In adoptive-transfer EAE, in which antigen-reactive T cells from WT mice were transferred to C6st1(-/-) and WT mice, phenotypes were significantly more severe in C6st1(-/-) than in WT mice. The recall response of antigen-reactive T cells was not significantly different among the groups. Furthermore, the number of pathogenic T cells within the CNS was also not considerably different. When EAE was induced in C6ST1 transgenic mice with C6ST1 overexpression, the mice showed considerably milder symptoms compared with those in WT mice. In conclusion, the presence of sulfate at position 6 of N-acetylgalactosamine of CSPG may influence the effecter phase of EAE to prevent the progression of pathogenesis. Thus, modification of the carbohydrate residue of CSPG may be a novel therapeutic strategy for neuroimmunological diseases such as multiple sclerosis.

  20. Methanogenic archaea and sulfate reducing bacteria co-cultured on acetate: teamwork or coexistence?

    Science.gov (United States)

    Ozuolmez, Derya; Na, Hyunsoo; Lever, Mark A; Kjeldsen, Kasper U; Jørgensen, Bo B; Plugge, Caroline M

    2015-01-01

    Acetate is a major product of fermentation processes and an important substrate for sulfate reducing bacteria and methanogenic archaea. Most studies on acetate catabolism by sulfate reducers and methanogens have used pure cultures. Less is known about acetate conversion by mixed pure cultures and the interactions between both groups. We tested interspecies hydrogen transfer and coexistence between marine methanogens and sulfate reducers using mixed pure cultures of two types of microorganisms. First, Desulfovibrio vulgaris subsp. vulgaris (DSM 1744), a hydrogenotrophic sulfate reducer, was cocultured together with the obligate aceticlastic methanogen Methanosaeta concilii using acetate as carbon and energy source. Next, Methanococcus maripaludis S2, an obligate H2- and formate-utilizing methanogen, was used as a partner organism to M. concilii in the presence of acetate. Finally, we performed a coexistence experiment between M. concilii and an acetotrophic sulfate reducer Desulfobacter latus AcSR2. Our results showed that D. vulgaris was able to reduce sulfate and grow from hydrogen leaked by M. concilii. In the other coculture, M. maripaludis was sustained by hydrogen leaked by M. concilii as revealed by qPCR. The growth of the two aceticlastic microbes indicated co-existence rather than competition. Altogether, our results indicate that H2 leaking from M. concilii could be used by efficient H2-scavengers. This metabolic trait, revealed from coculture studies, brings new insight to the metabolic flexibility of methanogens and sulfate reducers residing in marine environments in response to changing environmental conditions and community compositions. Using dedicated physiological studies we were able to unravel the occurrence of less obvious interactions between marine methanogens and sulfate-reducing bacteria.

  1. Methanogenic archaea and sulfate reducing bacteria co-cultured on acetate: teamwork or coexistence?

    Directory of Open Access Journals (Sweden)

    Derya eOzuolmez

    2015-05-01

    Full Text Available Acetate is a major product of fermentation processes and an important substrate for sulfate reducing bacteria and methanogenic archaea. Most studies on acetate catabolism by sulfate reducers and methanogens have used pure cultures. Less is known about acetate conversion by mixed pure cultures and the interactions between both groups. We tested interspecies hydrogen transfer and coexistence between marine methanogens and sulfate reducers using mixed pure cultures of two types of microorganisms. First, Desulfovibrio vulgaris subsp. vulgaris (DSM 1744, a hydrogenotrophic sulfate reducer, was cocultured together with the obligate aceticlastic methanogen Methanosaeta concilii using acetate as carbon and energy source. Next, Methanococcus maripaludis S2, an obligate H2- and formate-utilizing methanogen, was used as a partner organism to M. concilii in the presence of acetate. Finally, we performed a coexistence experiment between M. concilii and an acetotrophic sulfate reducer Desulfobacter latus AcSR2. Our results showed that D. vulgaris was able to reduce sulfate and grow from hydrogen leaked by M. concilii. In the other coculture, M. maripaludis was sustained by hydrogen leaked by M. concilii as revealed by qPCR. The growth of the two aceticlastic microbes indicated co-existence rather than competition. Altogether, our results indicate that H2 leaking from M. concilii could be used by efficient H2-scavengers. This metabolic trait, revealed from coculture studies, brings new insight to the metabolic flexibility of methanogens and sulfate reducers residing in marine environments in response to changing environmental conditions and community compositions. Using dedicated physiological studies we were able to unravel the occurrence of less obvious interactions between marine methanogens and sulfate-reducing bacteria.

  2. Involvement of AMP-activated protein kinase in control of adipocyte metabolism during starvation

    Czech Academy of Sciences Publication Activity Database

    Kopecký, Jan; Šponarová, Jana; Mustard, K. J.; Flachs, Pavel; Horáková, Olga; Rossmeisl, Martin; Bardová, Kristina; Thomason-Hughes, M.; Braunerová, Radka; Hardie, D. G.

    2005-01-01

    Roč. 6, č. S1 (2005), s. 52-52 ISSN 1467-7881. [European Congress on Obesity /14./. 01.06.2005-04.06.2005, Athens] R&D Projects: GA MŠk(CZ) 1M0520; GA ČR GA303/05/2580 Institutional research plan: CEZ:AV0Z50110509 Keywords : AMPK * adipocyte * starvation * fatty acid oxidation Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition

  3. Sulfate-Driven Elemental Sparing Is Regulated at the Transcriptional and Posttranscriptional Levels in a Filamentous Cyanobacterium▿ †

    Science.gov (United States)

    Gutu, Andrian; Alvey, Richard M.; Bashour, Sami; Zingg, Daniel; Kehoe, David M.

    2011-01-01

    Sulfur is an essential nutrient that can exist at growth-limiting concentrations in freshwater environments. The freshwater cyanobacterium Fremyella diplosiphon (also known as Tolypothrix sp. PCC 7601) is capable of remodeling the composition of its light-harvesting antennae, or phycobilisomes, in response to changes in the sulfur levels in its environment. Depletion of sulfur causes these cells to cease the accumulation of two forms of a major phycobilisome protein called phycocyanin and initiate the production of a third form of phycocyanin, which possesses a minimal number of sulfur-containing amino acids. Since phycobilisomes make up approximately 50% of the total protein in these cells, this elemental sparing response has the potential to significantly influence the fitness of this species under low-sulfur conditions. This response is specific for sulfate and occurs over the physiological range of sulfate concentrations likely to be encountered by this organism in its natural environment. F. diplosiphon has two separate sulfur deprivation responses, with low sulfate levels activating the phycobilisome remodeling response and low sulfur levels activating the chlorosis or bleaching response. The phycobilisome remodeling response results from changes in RNA abundance that are regulated at both the transcriptional and posttranscriptional levels. The potential of this response, and the more general bleaching response of cyanobacteria, to provide sulfur-containing amino acids during periods of sulfur deprivation is examined. PMID:21239582

  4. The confused world of sulfate attack on concrete

    International Nuclear Information System (INIS)

    Neville, Adam

    2004-01-01

    External sulfate attack is not completely understood. Part I identifies the issues involved, pointing out disagreements, and distinguishes between the mere occurrence of chemical reactions of sulfates with hydrated cement paste and the damage or deterioration of concrete; only the latter are taken to represent sulfate attack. Furthermore, sulfate attack is defined as deleterious action involving sulfate ions; if the reaction is physical, then, it is physical sulfate attack that takes place. The discussion of the two forms of sulfate attack leads to a recommendation for distinct nomenclature. Sulfate attack on concrete structures in service is not widespread, and the amount of laboratory-based research seems to be disproportionately large. The mechanisms of attack by different sulfates--sodium, calcium, and magnesium--are discussed, including the issue of topochemical and through-solution reactions. The specific aspects of the action of magnesium sulfate are discussed, and the differences between laboratory conditions and field exposure are pointed out. Part II discusses the progress of sulfate attack and its manifestations. This is followed by a discussion of making sulfate-resisting concrete. One of the measures is to use Type V cement, and this topic is extensively discussed. Likewise, the influence of w/c on sulfate resistance is considered. The two parameters are not independent of one another. Moreover, the cation in the sulfate salt has a strong bearing on the efficiency of the Type V cement. Recent interpretations of the Bureau of Reclamation tests, both long term and accelerated, are evaluated, and it appears that they need reworking. Part III reviews the standards and guides for the classification of the severity of exposure of structures to sulfates and points out the lack of calibration of the various classes of exposure. A particular problem is the classification of soils because much depends on the extraction ratio of sulfate in the soil: there is a

  5. Sulfation in lead-acid batteries

    Science.gov (United States)

    Catherino, Henry A.; Feres, Fred F.; Trinidad, Francisco

    Virtually, all military land vehicle systems use a lead-acid battery to initiate an engine start. The maintainability of these batteries and as a consequence, system readiness, has suffered from a lack of understanding of the reasons for battery failure. Often, the term most commonly heard for explaining the performance degradation of lead-acid batteries is the word, sulfation. Sulfation is a residual term that came into existence during the early days of lead-acid battery development. The usage is part of the legend that persists as a means for interpreting and justifying the eventual performance deterioration and failure of lead-acid batteries. The usage of this term is confined to the greater user community and, over time, has encouraged a myriad of remedies for solving sulfation problems. One can avoid the connotations associated with the all-inclusive word, sulfation by visualizing the general "sulfation" effect in terms of specific mechanistic models. Also, the mechanistic models are essential for properly understanding the operation and making proper use this battery system. It is evident that the better the model, the better the level of understanding.

  6. Sulfate and dissolved sulfide variation under low COD/Sulfate ratio in Up-flow Anaerobic Sludge Blanket (UASB treating domestic wastewater

    Directory of Open Access Journals (Sweden)

    Sérvio Túlio Alves Cassini

    2012-04-01

    Full Text Available In this study, the dynamics of sulfate reduction and dissolved sulfide generation (S2-, HS-, H2Saq in liquid phase was evaluated in an UASB reactor treating domestic wastewater with low COD/Sulfate content. The evaluation in the UASB reactor was performed at three sludge heights (0.25, 1.25, 2.25 taps and effluent of the reactor. Sulfate reduction was verified in the reactor, with an average reduction of 24 % throughout the experiment period. However, the dissolved sulfide concentration in the reactor was not higher than 5.0 mg Sdiss/L. The kinetic model of first order showed good fit to describe the sulfate reduction under different COD/sulfate ratio, with K1app between 2.94x10-5 s-1 and 1.17x10-5 s-1 with correlation coefficients for data over 91%. The maximum rate to sulfate reduction was 18.0 mg SO42-/L.h-1 and small variation in COD/sulfate ratio promotes a significant change both in sulfate and sulfide concentrations.

  7. The changes in the biochemical compositions and enzymatic activities of rotifer (Brachionus plicatilis, Müller) and Artemia during the enrichment and starvation periods.

    Science.gov (United States)

    Naz, Mehmet

    2008-12-01

    The changes in the biochemical compositions and enzymatic activities of rotifer (Brachionus plicatilis) and Artemia, enriched and stored at 4 degrees C temperature, were determined. The total starvation period was 16 h and samples were taken at the end of the 8th and 16th hours. In present study, the rotifer and nauplii catabolized a large proportion of the protein during the enrichment period. Lipid contents of both live preys increased during the enrichment period and decreased in nauplii and metanauplii throughout the starvation period but lipid content of the rotifer remained relatively constant during the starvation period. The changes observed in the amino acid compositions of Artemia and the rotifer were statistically significant (P < 0.05). The conspicuous decline the essential amino acid (EAA) and nonessential amino acid (NEAA) content of the rotifer was observed during the enrichment period. However, the essential amino acid (EAA) and nonessential amino acid (NEAA) contents of Artemia nauplii increased during the enrichment period. The unenriched and enriched rotifers contained more monounsaturated fatty acid (MUFAs) than polyunsaturated fatty acid (PUFAs) and saturated fatty acids (SFA). However, Artemia contained more PUFAs than MUFAs and SFA during the experimental period. A sharp increase in the amounts of docosahexaenoic acid (DHA) during the enrichment of the rotifer and Artemia nauplii was observed. However, the amount of DHA throughout the starvation period decreased in Artemia metanauplii but not in Artemia nauplii. Significant differences in tryptic, leucine aminopeptidase N (LAP), and alkaline phosphatase (AP) enzyme activities of Artemia and rotifer were observed during the enrichment and starvation period (P < 0.05). The digestive enzymes derived from live food to fish larvae provided the highest contribution at the end of the enrichment period. In conclusion, the results of the study provide important contributions to determine the most

  8. Complete and Voluntary Starvation of 50 Days

    Directory of Open Access Journals (Sweden)

    Bradley Elliott

    2016-09-01

    Full Text Available A 34-year-old obese male (96.8 kg; BMI, 30.2 kg m −1 volitionally undertook a 50-day fast with the stated goal of losing body mass. During this time, only tea, coffee, water, and a daily multivitamin were consumed. Severe and linear loss of body mass is recorded during these 50 days (final 75.4 kg; BMI, 23.5 kg mT 1 . A surprising resilience to effects of fasting on activity levels and physical function is noted. Plasma samples are suggestive of early impairment of liver function, and perturbations to cardiovascular dynamics are also noted. One month following resumption of feeding behavior, body weight was maintained (75.0 kg; BMI, 23.4 kg m −1 . Evidence-based decision-making with the fasting or hunger striking patient is limited by a lack of evidence. This case report suggests that total body mass, not mass lost, may be a key observation in clinical decision-making during fasting and starvation.

  9. Sulfate reduction in freshwater peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Oequist, M.

    1996-12-31

    This text consist of two parts: Part A is a literature review on microbial sulfate reduction with emphasis on freshwater peatlands, and part B presents the results from a study of the relative importance of sulfate reduction and methane formation for the anaerobic decomposition in a boreal peatland. The relative importance of sulfate reduction and methane production for the anaerobic decomposition was studied in a small raised bog situated in the boreal zone of southern Sweden. Depth distribution of sulfate reduction- and methane production rates were measured in peat sampled from three sites (A, B, and C) forming an minerotrophic-ombrotrophic gradient. SO{sub 4}{sup 2-} concentrations in the three profiles were of equal magnitude and ranged from 50 to 150 {mu}M. In contrast, rates of sulfate reduction were vastly different: Maximum rates in the three profiles were obtained at a depth of ca. 20 cm below the water table. In A it was 8 {mu}M h{sup -1} while in B and C they were 1 and 0.05 {mu}M h{sup -1}, respectively. Methane production rates, however, were more uniform across the three nutrient regimes. Maximum rates in A (ca. 1.5 {mu}g d{sup -1} g{sup -1}) were found 10 cm below the water table, in B (ca. 1.0 {mu}g d{sup -1} g{sup -1}) in the vicinity of the water table, and in C (0.75 {mu}g d{sup -1} g{sup -1}) 20 cm below the water table. In all profiles both sulfate reduction and methane production rates were negligible above the water table. The areal estimates of methane production for the profiles were 22.4, 9.0 and 6.4 mmol m{sup -2} d{sup -1}, while the estimates for sulfate reduction were 26.4, 2.5, and 0.1 mmol m{sup -2} d{sup -1}, respectively. The calculated turnover times at the sites were 1.2, 14.2, and 198.7 days, respectively. The study shows that sulfate reducing bacteria are important for the anaerobic degradation in the studied peatland, especially in the minerotrophic sites, while methanogenic bacteria dominate in ombrotrophic sites Examination

  10. Sulfate reduction in freshwater peatlands

    International Nuclear Information System (INIS)

    Oequist, M.

    1996-01-01

    This text consist of two parts: Part A is a literature review on microbial sulfate reduction with emphasis on freshwater peatlands, and part B presents the results from a study of the relative importance of sulfate reduction and methane formation for the anaerobic decomposition in a boreal peatland. The relative importance of sulfate reduction and methane production for the anaerobic decomposition was studied in a small raised bog situated in the boreal zone of southern Sweden. Depth distribution of sulfate reduction- and methane production rates were measured in peat sampled from three sites (A, B, and C) forming an minerotrophic-ombrotrophic gradient. SO 4 2- concentrations in the three profiles were of equal magnitude and ranged from 50 to 150 μM. In contrast, rates of sulfate reduction were vastly different: Maximum rates in the three profiles were obtained at a depth of ca. 20 cm below the water table. In A it was 8 μM h -1 while in B and C they were 1 and 0.05 μM h -1 , respectively. Methane production rates, however, were more uniform across the three nutrient regimes. Maximum rates in A (ca. 1.5 μg d -1 g -1 ) were found 10 cm below the water table, in B (ca. 1.0 μg d -1 g -1 ) in the vicinity of the water table, and in C (0.75 μg d -1 g -1 ) 20 cm below the water table. In all profiles both sulfate reduction and methane production rates were negligible above the water table. The areal estimates of methane production for the profiles were 22.4, 9.0 and 6.4 mmol m -2 d -1 , while the estimates for sulfate reduction were 26.4, 2.5, and 0.1 mmol m -2 d -1 , respectively. The calculated turnover times at the sites were 1.2, 14.2, and 198.7 days, respectively. The study shows that sulfate reducing bacteria are important for the anaerobic degradation in the studied peatland, especially in the minerotrophic sites, while methanogenic bacteria dominate in ombrotrophic sites Examination paper. 67 refs, 6 figs, 3 tabs

  11. Sulfate reduction and carbon removal during kraft char burning

    Energy Technology Data Exchange (ETDEWEB)

    Waag, K.J.; Frederick, W.J.; Sricharoenchaikul, V [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemical Engineering; Grace, T.M. [T.M. Grace Company, Appleton, WI (United States); Kymalainen, M. [Tampella Power, Tampere (Finland)

    1995-12-31

    An improved mathematical model of char burning during black liquor combustion was described. Enhancements include a proper treatment of CO{sub 2} and H{sub 2}O gasification, reactions between oxygen and combustibles in the boundary layer, and integration of sulfate reduction and sulfide reoxidation into the char burning process. Gasification of char carbon by reaction with H{sub 2}O and CO{sub 2} proved to be the most important means of carbon release under typical recovery furnace conditions. Sulfate reduction was shown to be responsible for only a minor part of the carbon release. Simulations showed that for typical recovery boiler conditions, char burning behavior is independent of oxygen concentration up to the point of carbon depletion. After carbon depletion, sulfide reoxidation occurs at a rate determined by oxygen mass transfer. Process variables that had the biggest effect on char burning behavior were initial black liquor drop diameter and temperature; also there was a direct link between char burnout times and the amount of sulfate reduction. At a given temperature, any variable that shortened the char burnout time resulted in proportionately less reduction. 22 refs., 10 figs., 2 tabs.

  12. Uniform Variation in Genetic-Traits of a Marine Bivalve Related to Starvation, Pollution and Geographic Clines

    NARCIS (Netherlands)

    Hummel, H.; Bogaards, R.H.; Amiard-Triquet, C.; Bachelet, G.; Desprez, M.; Marchand, J.; Rybarczyk, H.; Sylvand, B.; De Wit, Y.; De Wolf, L.

    1995-01-01

    Consistent patterns of genetic variation in the marine bivalve Macoma balthica (L.) were found after exposure to low levels of copper, starvation, and along geographic dines. The geographic dines were related to temperature and salinity. Genetic differences were primarily found in the LAP (Leucine

  13. Sulfation and cation effects on the conformational properties of the glycan backbone of chondroitin sulfate disaccharides.

    Science.gov (United States)

    Faller, Christina E; Guvench, Olgun

    2015-05-21

    Chondroitin sulfate (CS) is one of several glycosaminoglycans that are major components of proteoglycans. A linear polymer consisting of repeats of the disaccharide -4GlcAβ1-3GalNAcβ1-, CS undergoes differential sulfation resulting in five unique sulfation patterns. Because of the dimer repeat, the CS glycosidic "backbone" has two distinct sets of conformational degrees of freedom defined by pairs of dihedral angles: (ϕ1, ψ1) about the β1-3 glycosidic linkage and (ϕ2, ψ2) about the β1-4 glycosidic linkage. Differential sulfation and the possibility of cation binding, combined with the conformational flexibility and biological diversity of CS, complicate experimental efforts to understand CS three-dimensional structures at atomic resolution. Therefore, all-atom explicit-solvent molecular dynamics simulations with Adaptive Biasing Force sampling of the CS backbone were applied to obtain high-resolution, high-precision free energies of CS disaccharides as a function of all possible backbone geometries. All 10 disaccharides (β1-3 vs β1-4 linkage × five different sulfation patterns) were studied; additionally, ion effects were investigated by considering each disaccharide in the presence of either neutralizing sodium or calcium cations. GlcAβ1-3GalNAc disaccharides have a single, broad, thermodynamically important free-energy minimum, whereas GalNAcβ1-4GlcA disaccharides have two such minima. Calcium cations but not sodium cations bind to the disaccharides, and binding is primarily to the GlcA -COO(-) moiety as opposed to sulfate groups. This binding alters the glycan backbone thermodynamics in instances where a calcium cation bound to -COO(-) can act to bridge and stabilize an interaction with an adjacent sulfate group, whereas, in the absence of this cation, the proximity of a sulfate group to -COO(-) results in two like charges being both desolvated and placed adjacent to each other and is found to be destabilizing. In addition to providing information

  14. Development and validation of an alternative titration method for the determination of sulfate ion in indinavir sulfate

    Directory of Open Access Journals (Sweden)

    Breno de Carvalho e Silva

    2005-02-01

    Full Text Available A simple and rapid precipitation titration method was developed and validated to determine sulfate ion content in indinavir sulfate raw material. 0.1 mol L-1 lead nitrate volumetric solution was used as titrant employing potentiometric endpoint determination using a lead-specific electrode. The United States Pharmacopoeia Forum indicates a potentiometric method for sulfate ion quantitation using 0.1 mol L-1 lead perchlorate as titrant. Both methods were validated concerning linearity, precision and accuracy, yielding good results. The sulfate ion content found by the two validated methods was compared by the statistical t-student test, indicating that there was no statistically significant difference between the methods.

  15. Plant peroxisomes are degraded by starvation-induced and constitutive autophagy in tobacco BY-2 suspension-cultured cells.

    Science.gov (United States)

    Voitsekhovskaja, Olga V; Schiermeyer, Andreas; Reumann, Sigrun

    2014-01-01

    Very recently, autophagy has been recognized as an important degradation pathway for quality control of peroxisomes in Arabidopsis plants. To further characterize the role of autophagy in plant peroxisome degradation, we generated stable transgenic suspension-cultured cell lines of heterotrophic Nicotiana tabacum L. cv. Bright Yellow 2 expressing a peroxisome-targeted version of enhanced yellow fluorescent protein. Indeed, this cell line model system proved advantageous for detailed cytological analyses of autophagy stages and for quantification of cellular peroxisome pools under different culturing conditions and upon inhibitor applications. Complementary biochemical, cytological, and pharmacological analyses provided convincing evidence for peroxisome degradation by bulk autophagy during carbohydrate starvation. This degradation was slowed down by the inhibitor of autophagy, 3-methyladenine (3-MA), but the 3-MA effect ceased at advanced stages of starvation, indicating that another degradation mechanism for peroxisomes might have taken over. 3-MA also caused an increase particularly in peroxisomal proteins and cellular peroxisome numbers when applied under nutrient-rich conditions in the logarithmic growth phase, suggesting a high turnover rate for peroxisomes by basal autophagy under non-stress conditions. Together, our data demonstrate that a great fraction of the peroxisome pool is subject to extensive autophagy-mediated turnover under both nutrient starvation and optimal growth conditions. Our analyses of the cellular pool size of peroxisomes provide a new tool for quantitative investigations of the role of plant peroxisomes in reactive oxygen species metabolism.

  16. Transient exposure to oxygen or nitrate reveals ecophysiology of fermentative and sulfate-reducing benthic microbial populations.

    Science.gov (United States)

    Saad, Sainab; Bhatnagar, Srijak; Tegetmeyer, Halina E; Geelhoed, Jeanine S; Strous, Marc; Ruff, S Emil

    2017-12-01

    For the anaerobic remineralization of organic matter in marine sediments, sulfate reduction coupled to fermentation plays a key role. Here, we enriched sulfate-reducing/fermentative communities from intertidal sediments under defined conditions in continuous culture. We transiently exposed the cultures to oxygen or nitrate twice daily and investigated the community response. Chemical measurements, provisional genomes and transcriptomic profiles revealed trophic networks of microbial populations. Sulfate reducers coexisted with facultative nitrate reducers or aerobes enabling the community to adjust to nitrate or oxygen pulses. Exposure to oxygen and nitrate impacted the community structure, but did not suppress fermentation or sulfate reduction as community functions, highlighting their stability under dynamic conditions. The most abundant sulfate reducer in all cultures, related to Desulfotignum balticum, appeared to have coupled both acetate- and hydrogen oxidation to sulfate reduction. We describe a novel representative of the widespread uncultured candidate phylum Fermentibacteria (formerly candidate division Hyd24-12). For this strictly anaerobic, obligate fermentative bacterium, we propose the name ' U Sabulitectum silens' and identify it as a partner of sulfate reducers in marine sediments. Overall, we provide insights into the function of fermentative, as well as sulfate-reducing microbial communities and their adaptation to a dynamic environment. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  17. DNA microarray analysis of the cyanotroph Pseudomonas pseudoalcaligenes CECT5344 in response to nitrogen starvation, cyanide and a jewelry wastewater.

    Science.gov (United States)

    Luque-Almagro, V M; Escribano, M P; Manso, I; Sáez, L P; Cabello, P; Moreno-Vivián, C; Roldán, M D

    2015-11-20

    Pseudomonas pseudoalcaligenes CECT5344 is an alkaliphilic bacterium that can use cyanide as nitrogen source for growth, becoming a suitable candidate to be applied in biological treatment of cyanide-containing wastewaters. The assessment of the whole genome sequence of the strain CECT5344 has allowed the generation of DNA microarrays to analyze the response to different nitrogen sources. The mRNA of P. pseudoalcaligenes CECT5344 cells grown under nitrogen limiting conditions showed considerable changes when compared against the transcripts from cells grown with ammonium; up-regulated genes were, among others, the glnK gene encoding the nitrogen regulatory protein PII, the two-component ntrBC system involved in global nitrogen regulation, and the ammonium transporter-encoding amtB gene. The protein coding transcripts of P. pseudoalcaligenes CECT5344 cells grown with sodium cyanide or an industrial jewelry wastewater that contains high concentration of cyanide and metals like iron, copper and zinc, were also compared against the transcripts of cells grown with ammonium as nitrogen source. This analysis revealed the induction by cyanide and the cyanide-rich wastewater of four nitrilase-encoding genes, including the nitC gene that is essential for cyanide assimilation, the cyanase cynS gene involved in cyanate assimilation, the cioAB genes required for the cyanide-insensitive respiration, and the ahpC gene coding for an alkyl-hydroperoxide reductase that could be related with iron homeostasis and oxidative stress. The nitC and cynS genes were also induced in cells grown under nitrogen starvation conditions. In cells grown with the jewelry wastewater, a malate quinone:oxidoreductase mqoB gene and several genes coding for metal extrusion systems were specifically induced. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Adaptation of psychrophilic and psychrotrophic sulfate-reducing bacteria to permanently cold marine environments

    DEFF Research Database (Denmark)

    Isaksen, MF; Jørgensen, BB

    1996-01-01

    degrees C. The rates of sulfate reduction were measured by the (SO42-)-S-35 tracer technique at different experimental temperatures in sediment slurries, In sediment slurries from Mariager Fjord, sulfate reduction showed a mesophilic temperature response which was comparable to that of other temperate...... environments, In sediment slurries from Antarctica, the metabolic activity of psychrotrophic bacteria was observed with a respiration optimum at 18 to 19 degrees C during short-term incubations, However, over a 1-week incubation, the highest respiration rate was observed at 12.5 degrees C. Growth......The potential for sulfate reduction at low temperatures was examined in two different cold marine sediments, Mariager Fjord (Denmark), which is permanently cold (3 to 6 degrees C) but surrounded by seasonally warmer environments, and the Weddell Sea (Antarctica), which is permanently below 0...

  19. The combined therapy with chondroitin sulfate plus glucosamine sulfate or chondroitin sulfate plus glucosamine hydrochloride does not improve joint damage in an experimental model of knee osteoarthritis in rabbits.

    Science.gov (United States)

    Roman-Blas, Jorge A; Mediero, Aránzazu; Tardío, Lidia; Portal-Nuñez, Sergio; Gratal, Paula; Herrero-Beaumont, Gabriel; Largo, Raquel

    2017-01-05

    Osteoarthritis is the most common chronic joint disorder especially during aging. Although with controversies, glucosamine, both in its forms of sulfate and hydrochloride, and chondroitin sulfate are commonly employed to treat osteoarthritis. Due to the modest improve in the symptoms observed in patients treated with these drugs alone, a formulation combining both agents has been considered. The discrepant results achieved for pain control or structural improvement in osteoarthritis patients has been attributed to the quality of chemical formulations or different bias in clinical studies. The current study has been designed to test the effects of two different combined formulations with adequate pharmaceutical grade of these drugs in osteoarthritic joints, and to explore the underlying mechanisms modulated by both formulations in different osteoarthritis target tissues. Knee osteoarthritis was surgically induced in experimental rabbits. Some animals received the combined therapy (CT)1, (chondroitin sulfate 1200mg/day + glucosamine sulfate 1500mg/day), or the CT2 ((chondroitin sulfate 1200mg/day + glucosamine hydrochloride 1500mg/day). Neither CT1 nor CT2 significantly modified the cartilage damage or the synovial inflammation observed in osteoarthritic animals. Treatments were also unable to modify the presence of pro-inflammatory mediators, and the synthesis of metalloproteinases in the cartilage or in the synovium of osteoarthritic animals. Combined therapies did not modify the decrease in the subchondral bone mineral density observed in osteoarthritic rabbits. Therapies of chondroitin sulfate plus glucosamine sulfate or chondroitin sulfate plus glucosamine hydrochloride failed to improve structural damage or to ameliorate the inflammatory profile of joint tissues during experimental osteoarthritis. Published by Elsevier B.V.

  20. Highly sulfated hexasaccharide sequences isolated from chondroitin sulfate of shark fin cartilage: insights into the sugar sequences with bioactivities.

    Science.gov (United States)

    Mizumoto, Shuji; Murakoshi, Saori; Kalayanamitra, Kittiwan; Deepa, Sarama Sathyaseelan; Fukui, Shigeyuki; Kongtawelert, Prachya; Yamada, Shuhei; Sugahara, Kazuyuki

    2013-02-01

    Chondroitin sulfate (CS) chains regulate the development of the central nervous system in vertebrates and are linear polysaccharides consisting of variously sulfated repeating disaccharides, [-4GlcUAβ1-3GalNAcβ1-](n), where GlcUA and GalNAc represent D-glucuronic acid and N-acetyl-D-galactosamine, respectively. CS chains containing D-disaccharide units [GlcUA(2-O-sulfate)-GalNAc(6-O-sulfate)] are involved in the development of cerebellar Purkinje cells and neurite outgrowth-promoting activity through interaction with a neurotrophic factor, pleiotrophin, resulting in the regulation of signaling. In this study, to obtain further structural information on the CS chains containing d-disaccharide units involved in brain development, oligosaccharides containing D-units were isolated from a shark fin cartilage. Seven novel hexasaccharide sequences, ΔO-D-D, ΔA-D-D, ΔC-D-D, ΔE-A-D, ΔD-D-C, ΔE-D-D and ΔA-B-D, in addition to three previously reported sequences, ΔC-A-D, ΔC-D-C and ΔA-D-A, were isolated from a CS preparation of shark fin cartilage after exhaustive digestion with chondroitinase AC-I, which cannot act on the galactosaminidic linkages bound to D-units. The symbol Δ stands for a 4,5-unsaturated bond of uronic acids, whereas A, B, C, D, E and O represent [GlcUA-GalNAc(4-O-sulfate)], [GlcUA(2-O-sulfate)-GalNAc(4-O-sulfate)], [GlcUA-GalNAc(6-O-sulfate)], [GlcUA(2-O-sulfate)-GalNAc(6-O-sulfate)], [GlcUA-GalNAc(4-O-, 6-O-sulfate)] and [GlcUA-GalNAc], respectively. In binding studies using an anti-CS monoclonal antibody, MO-225, the epitopes of which are involved in cerebellar development in mammals, novel epitope structures, ΔA-D-A, ΔA-D-D and ΔA-B-D, were revealed. Hexasaccharides containing two consecutive D-units or a B-unit will be useful for the structural and functional analyses of CS chains particularly in the neuroglycobiological fields.

  1. Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate.

    Science.gov (United States)

    Irie, Fumitoshi; Badie-Mahdavi, Hedieh; Yamaguchi, Yu

    2012-03-27

    Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism.

  2. Starvation marrow – gelatinous transformation of bone marrow

    Directory of Open Access Journals (Sweden)

    Eric Osgood

    2014-09-01

    Full Text Available Gelatinous bone marrow transformation (GMT, also known as starvation marrow, represents a rare pathological entity of unclear etiology, in which bone marrow histopathology demonstrates hypoplasia, fat atrophy, and gelatinous infiltration. The finding of gelatinous marrow transformation lacks disease specificity; rather, it is an indicator of severe illness and a marker of poor nutritional status, found in patients with eating disorders, acute febrile illnesses, acquired immunodeficiency syndrome, alcoholism, malignancies, and congestive heart failure. We present a middle-aged woman with a history of alcoholism, depression, and anorexia nervosa who presented with failure to thrive and macrocytic anemia, with bone marrow examination demonstrative of gelatinous transformation, all of which resolved with appropriate treatment. To our knowledge, there are very few cases of GMT which have been successfully treated; thus, our case highlights the importance of proper supportive management.

  3. Effect of metakaolin on external sulfate attack

    Energy Technology Data Exchange (ETDEWEB)

    Ramlochan, T.; Thomas, M. [Toronto Univ., Dept. of Civil Engineering, ON (Canada)

    2000-07-01

    The effect of high reactivity metakaolin (HRM) on the sulfate resistance of mortars was studied. Mortar bars with three cements of varying C{sub 3}A content were used for the experiment. After a six month exposure to a 5 per cent solution of sodium sulfate, mortar bars incorporating any level of HRM as a partial replacement for a high-C{sub 3}A was considered 'moderately sulfate resistant'; mortar bars with HRM and a moderate or low C{sub 3}A content as 'high sulfate resistant'. It was also determined that for long term sulfate resistance 15 per cent HRM or more may be required, depending on the C{sub 3}A content. The performance of HRM was found to be significantly influenced by the water-cementitious material ratio, and in turn, by permeability, suggesting that HRM might increase sulfate resistance more by lowering the permeability of the concrete than by any chemical action. 7 refs., 4 tabs., 7 figs.

  4. Thermoluminescence of sulfated zircon exposed to gamma radiation

    International Nuclear Information System (INIS)

    Rubio, E.; Castano, V.M.; Mendoza A, E.; Gonzalez, P.R.

    2003-01-01

    In this work, the thermoluminescent (Tl) signal induced by gamma radiation in zirconia and sulfated zirconia samples embedded in Ptfe pellets is reported and discussed. In this case, samples were obtained through sol-gel method using zirconium n-propoxide and H 2 SO 4 as precursors, and later were subjected to thermal treatment at 600 C to obtain, the tetragonal phase accordingly to X-ray diffraction analysis. Experimental results show that the thermoluminescent glow peak depends on both, the crystalline structure and sulfate concentration. Two maximum peaks were observed located at 147 C and 274 C arising from the electronic transitions. Tl response as a function of the absorbed dose shows a linear increase for a wide of range exposure as well as good stability in time. The high sensitivity, dose linearity and signal stability of this material open the potential possibility to be used for the dosimetry applications. (Author)

  5. Process for removing sulfate anions from waste water

    Science.gov (United States)

    Nilsen, David N.; Galvan, Gloria J.; Hundley, Gary L.; Wright, John B.

    1997-01-01

    A liquid emulsion membrane process for removing sulfate anions from waste water is disclosed. The liquid emulsion membrane process includes the steps of: (a) providing a liquid emulsion formed from an aqueous strip solution and an organic phase that contains an extractant capable of removing sulfate anions from waste water; (b) dispersing the liquid emulsion in globule form into a quantity of waste water containing sulfate anions to allow the organic phase in each globule of the emulsion to extract and absorb sulfate anions from the waste water and (c) separating the emulsion including its organic phase and absorbed sulfate anions from the waste water to provide waste water containing substantially no sulfate anions.

  6. Nitrogen starvation affects bacterial adhesion to soil Adesão de bactérias desnutridas por nitrogênio a solo

    Directory of Open Access Journals (Sweden)

    Maria Tereza Borges

    2008-09-01

    Full Text Available One of the main factors limiting the bioremediation of subsoil environments based on bioaugmentation is the transport of selected microorganisms to the contaminated zones. The characterization of the physiological responses of the inoculated microorganisms to starvation, especially the evaluation of characteristics that affect the adhesion of the cells to soil particles, is fundamental to anticipate the success or failure of bioaugmentation. The objective of this study was to investigate the effect of nitrogen starvation on cell surface hydrophobicity and cell adhesion to soil particles by bacterial strains previously characterized as able to use benzene, toluene or xilenes as carbon and energy sources. The strains LBBMA 18-T (non-identified, Arthrobacter aurescens LBBMA 98, Arthrobacter oxydans LBBMA 201, and Klebsiella sp. LBBMA 204-1 were used in the experiments. Cultivation of the cells in nitrogen-deficient medium caused a significant reduction of the adhesion to soil particles by all the four strains. Nitrogen starvation also reduced significantly the strength of cell adhesion to the soil particles, except for Klebsiella sp. LBBMA 204-1. Two of the four strains showed significant reduction in cell surface hydrophobicity. It is inferred that the efficiency of bacterial transport through soils might be potentially increased by nitrogen starvation.Um dos principais fatores limitantes da biorremediação in situ de solos subterrâneos, baseada na bioaumentação, é o transporte dos microrganismos selecionados até o local contaminado. A caracterização das respostas fisiológicas dos microrganismos introduzidos no subsolo a condições de escassez nutricional, notadamente a avaliação de características que afetam a adesão celular ao solo, é fundamental para se prever o sucesso da bioaumentação. O objetivo deste trabalho foi determinar o efeito da desnutrição em meio com escassez de nitrogênio sobre a hidrofobicidade celular e a

  7. A potential role for chondroitin sulfate/dermatan sulfate in arm regeneration in Amphiura filiformis.

    Science.gov (United States)

    Ramachandra, Rashmi; Namburi, Ramesh B; Dupont, Sam T; Ortega-Martinez, Olga; van Kuppevelt, Toin H; Lindahl, Ulf; Spillmann, Dorothe

    2017-05-01

    Glycosaminoglycans (GAGs), such as chondroitin sulfate (CS) and dermatan sulfate (DS) from various vertebrate and invertebrate sources are known to be involved in diverse cellular mechanisms during repair and regenerative processes. Recently, we have identified CS/DS as the major GAG in the brittlestar Amphiura filiformis, with high proportions of di- and tri-O-sulfated disaccharide units. As this echinoderm is known for its exceptional regeneration capacity, we aimed to explore the role of these GAG chains during A. filiformis arm regeneration. Analysis of CS/DS chains during the regeneration process revealed an increase in the proportion of the tri-O-sulfated disaccharides. Conversely, treatment of A. filiformis with sodium chlorate, a potent inhibitor of sulfation reactions in GAG biosynthesis, resulted in a significant reduction in arm growth rates with total inhibition at concentrations higher than 5 mM. Differentiation was less impacted by sodium chlorate exposure or even slightly increased at 1-2 mM. Based on the structural changes observed during arm regeneration we identified chondroitin synthase, chondroitin-4-O-sulfotransferase 2 and dermatan-4-O-sulfotransferase as candidate genes and sought to correlate their expression with the expression of the A. filiformis orthologue of bone morphogenetic factors, AfBMP2/4. Quantitative amplification by real-time PCR indicated increased expression of chondroitin synthase and chondroitin-4-O-sulfotransferase 2, with a corresponding increase in AfBMP2/4 during regeneration relative to nonregenerating controls. Our findings suggest that proper sulfation of GAGs is important for A. filiformis arm regeneration and that these molecules may participate in mechanisms controlling cell proliferation. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Sulfate transport in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Simonsen, K

    1988-01-01

    1. In short-circuited toad skin preparations exposed bilaterally to NaCl-Ringer's containing 1 mM SO2(-4), influx of sulfate was larger than efflux showing that the skin is capable of transporting sulfate actively in an inward direction. 2. This active transport was not abolished by substituting...... apical Na+ for K+. 3. Following voltage activation of the passive Cl- permeability of the mitochondria-rich (m.r.) cells sulfate flux-ratio increased to a value predicted from the Ussing flux-ratio equation for a monovalent anion. 4. In such skins, which were shown to exhibit vanishingly small leakage...... conductances, the variation of the rate coefficient for sulfate influx (y) was positively correlated with the rate coefficient for Cl- influx (x), y = 0.035 x - 0.0077 cm/sec (r = 0.9935, n = 15). 5. Addition of the phosphodiesterase inhibitor, 3-isobutyl-1-methyl-xanthine to the serosal bath of short...

  9. N-sulfation of heparan sulfate is critical for syndecan-4-mediated podocyte cell-matrix interactions

    NARCIS (Netherlands)

    Sugar, T.; Wassenhove-McCarthy, D.J.; Orr, A.W.; Green, J.; Kuppevelt, T.H. van; McCarthy, K.J.

    2016-01-01

    Previous research has shown that podocytes unable to assemble heparan sulfate on cell surface proteoglycan core proteins have compromised cell-matrix interactions. This report further explores the role of N-sulfation of intact heparan chains in podocyte-matrix interactions. For the purposes of this

  10. Resistance to Starvation of Triatoma rubrofasciata (De Geer, 1773 under Laboratory Conditions (Hemiptera: Reduviidae: Triatominae

    Directory of Open Access Journals (Sweden)

    Rojas Cortéz Mirko G

    1998-01-01

    Full Text Available The present work aims at learning the period of resistance to starvation (molting/death of Triatoma rubrofasciata in different stages of development and the respective loss of weight until death. Eggs of specimens from the greater area of the city of São Luis in the State of Maranhão, Brazil, yielded approximately 300 nymphs. These nymphs were placed in labelled Borrel glasses, in which they were weekly fed on rats (Rattus norvegicus, until reaching the stage to be observed. The experiments were conducted in a climatic chamber regulated at 29 ± 1° C, 70% relative humidity and 12 hr photoperiod. The resistance to starvation increased according to the stage of development, except for adult bugs, whose results were similar to the 3rd stage nymphs. In all these development stages there was an abrupt loss of weight in the first week, followed by a gradual loss until death. Comparing this work with those of other authors, it was observed that T. rubrofasciata is among the less resistant triatomine species.

  11. Multi-model comparison of the volcanic sulfate deposition from the 1815 eruption of Mt. Tambora

    Directory of Open Access Journals (Sweden)

    L. Marshall

    2018-02-01

    Full Text Available The eruption of Mt. Tambora in 1815 was the largest volcanic eruption of the past 500 years. The eruption had significant climatic impacts, leading to the 1816 year without a summer, and remains a valuable event from which to understand the climatic effects of large stratospheric volcanic sulfur dioxide injections. The eruption also resulted in one of the strongest and most easily identifiable volcanic sulfate signals in polar ice cores, which are widely used to reconstruct the timing and atmospheric sulfate loading of past eruptions. As part of the Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP, five state-of-the-art global aerosol models simulated this eruption. We analyse both simulated background (no Tambora and volcanic (with Tambora sulfate deposition to polar regions and compare to ice core records. The models simulate overall similar patterns of background sulfate deposition, although there are differences in regional details and magnitude. However, the volcanic sulfate deposition varies considerably between the models with differences in timing, spatial pattern and magnitude. Mean simulated deposited sulfate on Antarctica ranges from 19 to 264 kg km−2 and on Greenland from 31 to 194 kg km−2, as compared to the mean ice-core-derived estimates of roughly 50 kg km−2 for both Greenland and Antarctica. The ratio of the hemispheric atmospheric sulfate aerosol burden after the eruption to the average ice sheet deposited sulfate varies between models by up to a factor of 15. Sources of this inter-model variability include differences in both the formation and the transport of sulfate aerosol. Our results suggest that deriving relationships between sulfate deposited on ice sheets and atmospheric sulfate burdens from model simulations may be associated with greater uncertainties than previously thought.

  12. Immobilization of calcium sulfate contained in demolition waste

    International Nuclear Information System (INIS)

    Ambroise, J.; Pera, J.

    2008-01-01

    This paper presents the results of a laboratory study undertaken to examine the treatment of demolition waste containing calcium sulfate by means of calcium sulfoaluminate clinker (CSA). The quantity of CSA necessary to entirely consume calcium sulfate was determined. Using infrared spectrometry analysis and X-ray diffraction, it was shown that calcium sulfate was entirely consumed when the ratio between CSA and calcium sulfate was 4. Standard sand was polluted by 4% calcium sulfate. Two solutions were investigated: ·either global treatment of sand by CSA, ·or immobilization of calcium sulfate by CSA, followed by the introduction of this milled mixture in standard sand. Regardless of the type of treatment, swelling was almost stabilized after 28 days of immersion in water

  13. Acid Sulfate Alteration on Mars

    Science.gov (United States)

    Ming, D. W.; Morris, R. V.

    2016-01-01

    A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Acid sulfate alteration has been identified at all three landing sites visited by NASA rover missions (Spirit, Opportunity, and Curiosity). Spirit landed in Gusev crater in 2004 and discovered Fe-sulfates and materials that have been extensively leached by acid sulfate solutions. Opportunity landing on the plains of Meridiani Planum also in 2004 where the rover encountered large abundances of jarosite and hematite in sedimentary rocks. Curiosity landed in Gale crater in 2012 and has characterized fluvial, deltaic, and lacustrine sediments. Jarosite and hematite were discovered in some of the lacustrine sediments. The high elemental abundance of sulfur in surface materials is obvious evidence that sulfate has played a major role in aqueous processes at all landing sites on Mars. The sulfate-rich outcrop at Meridiani Planum has an SO3 content of up to 25 wt.%. The interiors of rocks and outcrops on the Columbia Hills within Gusev crater have up to 8 wt.% SO3. Soils at both sites generally have between 5 to 14 wt.% SO3, and several soils in Gusev crater contain around 30 wt.% SO3. After normalization of major element compositions to a SO3-free basis, the bulk compositions of these materials are basaltic, with a few exceptions in Gusev crater and in lacustrine mudstones in Gale crater. These observations suggest that materials encountered by the rovers were derived from basaltic precursors by acid sulfate alteration under nearly isochemical conditions (i.e., minimal leaching). There are several cases, however, where acid sulfate alteration minerals (jarosite and hematite) formed in open hydrologic systems, e.g., in Gale crater lacustrine mudstones. Several hypotheses have been suggested for the

  14. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

    Science.gov (United States)

    McCue, Marshall D; Guzman, R Marena; Passement, Celeste A; Davidowitz, Goggy

    2015-01-01

    Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.

  15. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

    Directory of Open Access Journals (Sweden)

    Marshall D McCue

    Full Text Available Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae were still relying extensively on lipids at the time of death, other species (crickets and moth larvae allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.

  16. Tomato strigolactones are derived from carotenoids and their biosynthesis is promoted by phosphate starvation

    OpenAIRE

    López-Ráez, Juan A.; Charnikhova, Tatsiana;; Gómez-Roldán,Victoria;; Matusova, Radoslava;; Kohlen, Wouter;; De Vos, Ric;; Verstappe, Francel;; Puech-Pages, Virginie;; Bécard, Guillaume;; Mulder, Patrick;; Bouwmeester, Harro;

    2008-01-01

    Strigolactones are rhizosphere signalling compounds that mediate host location in arbuscular mycorrhizal (AM) fungi and parasitic plants. Here, the regulation of the biosynthesis of strigolactones is studied in tomato (Solanum lycopersicum). * Strigolactone production under phosphate starvation, in the presence of the carotenoid biosynthesis inhibitor fluridone and in the abscisic acid (ABA) mutant notabilis were assessed using a germination bioassay with seeds of Orobanche ramosa; a hyphal b...

  17. STARVATION RESISTANCE IN DROSOPHILA-MELANOGASTER IN RELATION TO THE POLYMORPHISMS AT THE ADH AND ALPHA-GPDH LOCI

    NARCIS (Netherlands)

    OUDMAN, L; VANDELDEN, W; KAMPING, A; BIJLSMA, R

    In view of the world-wide latitudinal cline of the Adh and alpha Gpdh allozyme frequencies of Drosophila melanogaster and the interactions between these loci, experiments were performed to study the phenotypic effects of these loci. Starvation resistance, oxygen consumption, body weight, protein

  18. Mencegah Pembentukan Kalsium Sulfat pada Desalinasi Air Laut

    Directory of Open Access Journals (Sweden)

    Mirna Rahmah Lubis

    2007-06-01

    Full Text Available Resin penukar-anion, Relite MG 1/P, dapat digunakan untuk memisahkan sulfat dalam air laut guna mencegah pembentukan kerak kalsium sulfat pada heat exchanger. Resin tersebut menunjukkan selektivitas sulfat yang tinggi dalam air laut sintetis. Resin yang telah dipakai dapat diregenerasi menggunakan air asin yang dipekatkan dengan asam hingga mencapai pH 4. Untuk waktu pemakaian dan regenerasi yang sama, faktor konsentrasi desalinasi (misalnya 2 hingga 4 menaikkan konsentrasi klorida dalam air asin yang diblowdown. Dengan faktor konsentrasi yang tetap, kenaikan laju alir (pengurangan waktu pemakaian dan regenerasi memperendah efisiensi regenerasi dan menaikkan pemisahan sulfat. Akibat kelarutan kalsium sulfat yang bersifat terbalik tersebut, temperatur air asin yang tinggi memerlukan pemisahan sulfat yang lebih banyak, yang dapat dicapai dengan mengurangi laju alir air laut. Pengurangan laju alir tersebut membutuhkan peralatan yang lebih besar dan resin yang lebih banyak, sehingga biaya modal bertambah. Untuk pabrik desalinasi dengan kapasitas produksi 1 juta gallon per hari dan faktor konsentrasi sebesar 2, biaya pemisahan sulfat meliputi biaya resin dan biaya peralatan. Biaya tersebut bervariasi dari $0.246 hingga $0.356/kgalon (per ribu galon air yang diproduksi karena temperatur maksimum air asin berubah dari 140°C menjadi 180°C. Keywords: desalinasi air laut, ion exchange, kalsium sulfat, kerak; mechanical vapor compression (MVC, pemisahan sulfat, resin penukar-anion basa lemah

  19. Some effects of temperature and starvation on the bivalve @iDonax vittatus@@ (da Costa) in experimental laboratory populations

    Digital Repository Service at National Institute of Oceanography (India)

    Ansell, A.D.; Sivadas, P.

    The effect of temperature on the body weight and composition, and on respiration, filtration and NH, excretion of the bivalve Donax uittatus (da Costa) has been investigated in laboratory-maintained populations under conditions of starvation In all...

  20. Streptomyces lunalinharesii 235 prevents the formation of a sulfate-reducing bacterial biofilm

    Directory of Open Access Journals (Sweden)

    Juliana Pacheco da Rosa

    Full Text Available ABSTRACT Streptomyces lunalinharesii strain 235 produces an antimicrobial substance that is active against sulfate reducing bacteria, the major bacterial group responsible for biofilm formation and biocorrosion in petroleum reservoirs. The use of this antimicrobial substance for sulfate reducing bacteria control is therefore a promising alternative to chemical biocides. In this study the antimicrobial substance did not interfere with the biofilm stability, but the sulfate reducing bacteria biofilm formation was six-fold smaller in carbon steel coupons treated with the antimicrobial substance when compared to the untreated control. A reduction in the most probable number counts of planktonic cells of sulfate reducing bacteria was observed after treatments with the sub-minimal inhibitory concentration, minimal inhibitory concentration, and supra-minimal inhibitory concentration of the antimicrobial substance. Additionally, when the treated coupons were analyzed by scanning electron microscopy, the biofilm formation was found to be substantially reduced when the supra-minimal inhibitory concentration of the antimicrobial substance was used. The coupons used for the biofilm formation had a small weight loss after antimicrobial substance treatment, but corrosion damage was not observed by scanning electron microscopy. The absence of the dsrA gene fragment in the scraped cell suspension after treatment with the supra-minimal inhibitory concentration of the antimicrobial substance suggests that Desulfovibrio alaskensis was not able to adhere to the coupons. This is the first report on an antimicrobial substance produced by Streptomyces active against sulfate reducing bacteria biofilm formation. The application of antimicrobial substance as a potential biocide for sulfate reducing bacteria growth control could be of great interest to the petroleum industry.

  1. EFFECT OF MAGNESIUM SULFATE (A LAXATIVE) ON ...

    African Journals Online (AJOL)

    use with little success . Magnesium sulfate also known as Epsom salt or bitter salt is a hydrate salt with a chemical name of magnesium sulfate heptahydrate . Chemical formula is MgSO. 7HO and trade name is. Andrews liver salt. Dried magnesium sulfate is an osmotic laxative or a saline laxative that acts by increasing the.

  2. Are phloem-derived amino acids the origin of the elevated malate concentration in the xylem sap following mineral N starvation in soybean?

    Science.gov (United States)

    Vitor, Simone C; do Amarante, Luciano; Sodek, Ladaslav

    2018-05-16

    A substantial increase in malate in the xylem sap of soybean subjected to mineral N starvation originates mainly from aspartate, a prominent amino acid of the phloem. A substantial increase in xylem malate was found when non-nodulated soybean plants were transferred to a N-free medium. Nodulated plants growing in the absence of mineral N and, therefore, dependent on symbiotic N 2 fixation also contained elevated concentrations of malate in the xylem sap. When either nitrate or ammonium was supplied, malate concentrations in the xylem sap were low, both for nodulated and non-nodulated plants. Evidence was obtained that the elevated malate concentration of the xylem was derived from amino acids supplied by the phloem. Aspartate was a prominent component of the phloem sap amino acids and, therefore, a potential source of malate. Supplying the roots of intact plants with 13 C-aspartate revealed that malate of the xylem sap was readily labelled under N starvation. A hypothetical scheme is proposed whereby aspartate supplied by the phloem is metabolised in the roots and the products of this metabolism cycled back to the shoot. Under N starvation, aspartate metabolism is diverted from asparagine synthesis to supply N for the synthesis of other amino acids via transaminase activity. The by-product of aspartate transaminase activity, oxaloacetate, is transformed to malate and its export accounts for much of the elevated concentration of malate found in the xylem sap. This mechanism represents a new additional role for malate during mineral N starvation of soybean, beyond that of charge balance.

  3. Extraction of beryllium sulfate by a long chain amine; Extraction du sulfate de beryllium par une amine a longue chaine

    Energy Technology Data Exchange (ETDEWEB)

    Etaix, E.S. [Commissariat a l' Energie Atomique, Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-06-01

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author) [French] L'etude de l'extraction de l'acide sulfurique en solution aqueuse par une amine primaire en solution dans le benzene, le diethyl-3,9 amino-6 tridecane (D.E.T.) - autre nom americain 1-3 (ethylpentyl) - 4-ethyloctylamine (E.P.O.) a permis de calculer les constantes de formation du sulfate et de l'hydrogenosulfate d'alkyl-ammonium. La formule du complexe de sulfate de beryllium et d'alkyl-ammonium forme en solution benzenique a ete ensuite determinee pour diverses acidites initiales de la solution aqueuse. Enfin, l'influence de la concentration des ions sulfate de la phase aqueuse sur l'extraction du beryllium a mis en evidence la formation en solution aqueuse de complexes anioniques de sulfate et de beryllium dont la constante de formation a ete evaluee. (auteur)

  4. Extraction of beryllium sulfate by a long chain amine; Extraction du sulfate de beryllium par une amine a longue chaine

    Energy Technology Data Exchange (ETDEWEB)

    Etaix, E S [Commissariat a l' Energie Atomique, Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-06-01

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author) [French] L'etude de l'extraction de l'acide sulfurique en solution aqueuse par une amine primaire en solution dans le benzene, le diethyl-3,9 amino-6 tridecane (D.E.T.) - autre nom americain 1-3 (ethylpentyl) - 4-ethyloctylamine (E.P.O.) a permis de calculer les constantes de formation du sulfate et de l'hydrogenosulfate d'alkyl-ammonium. La formule du complexe de sulfate de beryllium et d'alkyl-ammonium forme en solution benzenique a ete ensuite determinee pour diverses acidites initiales de la solution aqueuse. Enfin, l'influence de la concentration des ions sulfate de la phase aqueuse sur l'extraction du beryllium a mis en evidence la formation en solution aqueuse de complexes anioniques de sulfate et de beryllium dont la constante de formation a ete evaluee. (auteur)

  5. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario, E-mail: mariodiaz@uniovi.es

    2014-02-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h{sup −1} and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y{sub X/S} of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m{sup 2}.

  6. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    International Nuclear Information System (INIS)

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario

    2014-01-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h −1 and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y X/S of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m 2

  7. Physico-chemical studies for strontium sulfate radiation dosimeter

    Directory of Open Access Journals (Sweden)

    M.A.H. Rushdi

    2015-04-01

    Full Text Available Anhydrous strontium sulfate (SrSO4 has shown a promise candidate as a dosimeter for low dose applications producing unique EPR signals with γ-rays which it has a linear response relationship (r2 = 0.999 in the range of 1–100 Gy. The present study extended to evaluate the properties of strontium sulfate dosimeter in intermediate dose range of technology applications. It was observed that the intensity of the EPR signal at g = 2.01081 increases with a 3rd polynomial function in the range of 0.10–15 kGy. In addition, the radical (SO4− provides a stable signal with a good reproducibility (0.107%. Other physics characteristic including the collision of mass stopping power dependence of the system and the effect of atomic number in different energy regions were investigated. The uncertainty budget for high doses has obtained from the measurement with value of 3.57% at 2σ confidence level.

  8. Chondroitin-6-sulfate attenuates inflammatory responses in murine macrophages via suppression of NF-κB nuclear translocation.

    Science.gov (United States)

    Tan, Guak-Kim; Tabata, Yasuhiko

    2014-06-01

    Inflammation is a host protective response to noxious stimuli, and excessive production of pro-inflammatory mediators by macrophages (mφ) can lead to numerous pathological conditions. In this study, immunomodulatory effects of immobilized and soluble glycosaminoglycans (GAGs) on mouse-bone-marrow-derived mφ were compared by measuring nitric oxide (NO). We demonstrate here that all GAGs studied except for heparin were able to modulate interferon-γ/lipopolysaccharide (IFN-γ/LPS)-induced NO release by mφ to varying extents after 24h of incubation. In particular, the modulatory activities of soluble chondroitin-6-sulfate (C6S), hyaluronic acid and heparan sulfate altered markedly after covalent immobilization. Of these, soluble C6S exhibited the strongest NO inhibitory activity, and the inhibition was dose- and time-dependent. Moreover, C6S significantly reduced pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α production by IFN-γ/LPS- or LPS-activated mφ. Specifically, the C6S-mediated suppression of mφ pro-inflammatory phenotype was accompanied by an increase in the IL-10 level, suggesting a possible switch towards anti-inflammatory/wound healing M2 state. In addition, the highest magnitude of inhibitory effects was obtained when cells were pre-treated with C6S prior to IFN-γ/LPS or LPS challenge, suggesting an additional role for C6S in protection against microbial infection. Further investigations reveal that the anti-inflammatory effects of C6S on activated mφ may be ascribed at least in part to suppression of NF-κB nuclear translocation. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. The effect of starvation and re-feeding on mitochondrial potential in the midgut of Neocaridina davidi (Crustacea, Malacostraca.

    Directory of Open Access Journals (Sweden)

    Agnieszka Włodarczyk

    Full Text Available The midgut in the freshwater shrimp Neocaridina davidi (previously named N. heteropoda (Crustacea, Malacostraca is composed of a tube-shaped intestine and a large hepatopancreas that is formed by numerous blind-ended tubules. The precise structure and ultrastructure of these regions were presented in our previous papers, while here we focused on the ultrastructural changes that occurred in the midgut epithelial cells (D-cells in the intestine, B- and F- cells in the hepatopancreas after long-term starvation and re-feeding. We used transmission electron microscopy, light and confocal microscopes and flow cytometry to describe all of the changes that occurred due to the stressor with special emphasis on mitochondrial alterations. A quantitative assessment of cells with depolarized mitochondria helped us to establish whether there is a relationship between starvation, re-feeding and the inactivation/activation of mitochondria. The results of our studies showed that in the freshwater shrimp N. davidi that were analyzed, long-term starvation activates the degeneration of epithelial cells at the ultrastructural level and causes an increase of cells with depolarized (non-active mitochondria. The process of re-feeding leads to the gradual regeneration of the cytoplasm of the midgut epithelial cells; however, these changes were observed at the ultrastructural level. Additionally, re-feeding causes the regeneration of mitochondrial ultrastructure. Therefore, we can state that the increase in the number of cells with polarized mitochondria occurs slowly and does not depend on ultrastructural alterations.

  10. The effect of starvation and re-feeding on mitochondrial potential in the midgut of Neocaridina davidi (Crustacea, Malacostraca).

    Science.gov (United States)

    Włodarczyk, Agnieszka; Sonakowska, Lidia; Kamińska, Karolina; Marchewka, Angelika; Wilczek, Grażyna; Wilczek, Piotr; Student, Sebastian; Rost-Roszkowska, Magdalena

    2017-01-01

    The midgut in the freshwater shrimp Neocaridina davidi (previously named N. heteropoda) (Crustacea, Malacostraca) is composed of a tube-shaped intestine and a large hepatopancreas that is formed by numerous blind-ended tubules. The precise structure and ultrastructure of these regions were presented in our previous papers, while here we focused on the ultrastructural changes that occurred in the midgut epithelial cells (D-cells in the intestine, B- and F- cells in the hepatopancreas) after long-term starvation and re-feeding. We used transmission electron microscopy, light and confocal microscopes and flow cytometry to describe all of the changes that occurred due to the stressor with special emphasis on mitochondrial alterations. A quantitative assessment of cells with depolarized mitochondria helped us to establish whether there is a relationship between starvation, re-feeding and the inactivation/activation of mitochondria. The results of our studies showed that in the freshwater shrimp N. davidi that were analyzed, long-term starvation activates the degeneration of epithelial cells at the ultrastructural level and causes an increase of cells with depolarized (non-active) mitochondria. The process of re-feeding leads to the gradual regeneration of the cytoplasm of the midgut epithelial cells; however, these changes were observed at the ultrastructural level. Additionally, re-feeding causes the regeneration of mitochondrial ultrastructure. Therefore, we can state that the increase in the number of cells with polarized mitochondria occurs slowly and does not depend on ultrastructural alterations.

  11. Low light intensity and nitrogen starvation modulate the chlorophyll content of Scenedesmus dimorphus.

    Science.gov (United States)

    Ferreira, V S; Pinto, R F; Sant'Anna, C

    2016-03-01

    Chlorophyll is a photosynthetic pigment found in plants and algal organisms and is a bioproduct with human health benefits and a great potential for use in the food industry. The chlorophyll content in microalgae strains varies in response to environmental factors. In this work, we assessed the effect of nitrogen depletion and low light intensity on the chlorophyll content of the Scenedesmus dimorphus microalga. The growth of S. dimorphus under low light intensity led to a reduction in cell growth and volume as well as increased cellular chlorophyll content. Nitrogen starvation led to a reduction in cell growth and the chlorophyll content, changes in the yield and productivity of chlorophylls a and b. Transmission electron microscopy was used to investigate the ultrastructural changes in the S. dimorphus exposed to nitrogen and light deficiency. In contrast to nitrogen depletion, low light availability was an effective mean for increasing the total chlorophyll content of green microalga S. dimorphus. The findings acquired in this work are of great biotechnological importance to extend knowledge of choosing the right culture condition to stimulate the effectiveness of microalgae strains for chlorophyll production purposes. © 2015 The Society for Applied Microbiology.

  12. Effects of starvation on protein synthesis and nucleic acid metabolism in the muscle of the barred sand bass Paralabrax nebulifer

    Energy Technology Data Exchange (ETDEWEB)

    Lowery, M.S.

    1987-01-01

    Starvation induced different protein synthesis responses in red and white muscle of the barred sand bass Paralabrax nebulifer. Red muscle had /sup 14/C-leucine incorporation rates into total protein which were several times higher than white muscle in both the fed and starved states. Muscle was separated into a myofibrillar fraction consisting of the structural proteins and a sarcoplasmic fraction consisting of soluble proteins. Synthesis of the myofibrillar fraction of white muscle decreased by 90%, while red muscle myofibrillar synthesis remained essentially unchanged. Changes in the labeling of several enzymes purified from the sarcoplasmic fraction were different even though the overall loss of enzyme activity was similar, suggesting that changes in synthesis rates were important in maintaining appropriate relative enzyme concentrations.

  13. Kibra and aPKC regulate starvation-induced autophagy in Drosophila

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Ahrum [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Neufeld, Thomas P. [Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455 (United States); Choe, Joonho, E-mail: jchoe@kaist.ac.kr [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of)

    2015-12-04

    Autophagy is a bulk degradation system that functions in response to cellular stresses such as metabolic stress, endoplasmic reticulum stress, oxidative stress, and developmental processes. During autophagy, cytoplasmic components are captured in double-membrane vesicles called autophagosomes. The autophagosome fuses with the lysosome, producing a vacuole known as an autolysosome. The cellular components are degraded by lysosomal proteases and recycled. Autophagy is important for maintaining cellular homeostasis, and the process is evolutionarily conserved. Kibra is an upstream regulator of the hippo signaling pathway, which controls organ size by affecting cell growth, proliferation, and apoptosis. Kibra is mainly localized in the apical membrane domain of epithelial cells and acts as a scaffold protein. We found that Kibra is required for autophagy to function properly. The absence of Kibra caused defects in the formation of autophagic vesicles and autophagic degradation. We also found that the well-known cell polarity protein aPKC interacts with Kibra, and its activity affects autophagy upstream of Kibra. Constitutively active aPKC decreased autophagic vesicle formation and autophagic degradation. We confirmed the interaction between aPKC and Kibra in S2 cells and Drosophila larva. Taken together, our data suggest that Kibra and aPKC are essential for regulating starvation-induced autophagy. - Highlights: • Loss of Kibra causes defects in autophagosome formation and autophagic degradation. • Constitutively-active aPKCs negatively regulate autophagy. • Kibra interacts with aPKC in vitro and in vivo. • Kibra regulates autophagy downstream of aPKC.

  14. Modeling and minimization of barium sulfate scale

    Science.gov (United States)

    Alan W. Rudie; Peter W. Hart

    2006-01-01

    The majority of the barium present in the pulping process exits the digester as barium carbonate. Barium carbonate dissolves in the bleach plant when the pH drops below 7 and, if barium and sulfate concentrations are too high, begins to precipitate as barium sulfate. Barium is difficult to control because a mill cannot avoid this carbonate-to-sulfate transition using...

  15. Separation of hydroxynorketamine stereoisomers using capillary electrophoresis with sulfated β-cyclodextrin and highly sulfated γ-cyclodextrin.

    Science.gov (United States)

    Sandbaumhüter, Friederike A; Theurillat, Regula; Thormann, Wolfgang

    2017-08-01

    The racemic N-methyl-d-aspartate receptor antagonist ketamine is used in anesthesia, analgesia and the treatment of depressive disorders. It is known that interactions of hydroxylated norketamine metabolites and 5,6-dehydronorketamine (DHNK) with the α 7 -nicotinic acetylcholine receptor and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor are responsible for the antidepressive effects. Ketamine and its first metabolite norketamine are not active on these receptors. As stereoselectivity plays a role in ketamine metabolism, a cationic capillary electrophoresis based method capable of resolving and analyzing the stereoisomers of four hydroxylated norketamine metabolites, norketamine and DHNK was developed. The assay is based on liquid/liquid extraction of the analytes from the biological matrix, electrokinetic sample injection across a buffer plug and analysis of the stereoisomers in a phosphate background electrolyte (BGE) at pH 3 comprising a mixture of sulfated β-cyclodextrin (5 mg/mL) and highly sulfated γ-cyclodextrin (0.1%). The method was used to analyze samples of an in vitro study in which ketamine was incubated with equine liver microsomes and in plasma samples of dogs and horses that were collected after an i.v. bolus injection of racemic ketamine. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Sulfate resistance of nanosilica contained Portland cement mortars

    Science.gov (United States)

    Batilov, Iani B.

    Soils, sea water and ground water high in sulfates are commonly encountered hostile environments that can attack the structure of concrete via chemical and physical mechanisms which can lead to costly repairs or replacement. Sulfate attack is a slow acting deteriorative phenomenon that can result in cracking, spalling, expansion, increased permeability, paste-to-aggregate bond loss, paste softening, strength loss, and ultimately, progressive failure of concrete. In the presented research study, Portland cement (PC) mortars containing 1.5% to 6.0% nanosilica (nS) cement replacement by weight were tested for sulfate resistance through full submersion in sodium sulfate to simulate external sulfate attack. Mortars with comparable levels of cement replacement were also prepared with microsilica (mS). Three cement types were chosen to explore nS' effectiveness to reduce sulfate expansion, when paired with cements of varying tricalcium aluminate (C3A) content and Blaine fineness, and compare it to that of mS. Mortars were also made with combined cement replacement of equal parts nS and mS to identify if they were mutually compatible and beneficial towards sulfate resistance. Besides sulfate attack expansion of mortar bars, the testing program included investigations into transport and microstructure properties via water absorption, sulfate ion permeability, porosimetry, SEM with EDS, laser diffraction, compressive strength, and heat of hydration. Expansion measurements indicated that mS replacement mortars outperformed both powder form nS, and nS/mS combined replacement mixtures. A negative effect of the dry nS powder replacement attributed to agglomeration of its nanoparticles during mixing negated the expected superior filler, paste densification, and pozzolanic activity of the nanomaterial. Agglomerated nS was identified as the root cause behind poor performance of nS in comparison to mS for all cement types, and the control when paired with a low C3A sulfate resistant

  17. Integrated approach for investigating the durability of self-consolidating concrete to sulfate attack

    Science.gov (United States)

    Bassuoni, Mohamed Tamer F.

    The growing use of self-consolidating concrete (SCC) in various infrastructure applications exposed to sulfate-rich environments necessitates conducting comprehensive research to evaluate its durability to external sulfate attack. Since the reliability and adequacy of standard sulfate immersion tests have been questioned, the current thesis introduced an integrated testing approach for assessing the durability of a wide scope of SCC mixtures to external sulfate attack. This testing approach involved progressive levels of complexity from single to multiple damage processes. A new series of sulfate attack tests involving multiple field-like parameters and combined damage mechanisms (various cations, controlled pH, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading) were designed to evaluate the performance (suitability) of the SCC mixtures under various sulfate attack exposure scenarios. The main mixture design variables of SCC included the type of binder (single, binary, ternary and quaternary), air-entrainment, sand-to-aggregate mass ratio and hybrid fibre reinforcement. The comprehensive database and knowledge obtained from this research were used to develop smart models (fuzzy and neuro-fuzzy inference systems) based on artificial-intelligence to evaluate and predict the performance of the SCC mixtures under various sulfate attack exposure regimes implemented in this study. In full immersion tests involving high concentration sodium and magnesium sulfate solutions with controlled pH, the low penetrability of SCC was responsible for the high durability of specimens. Ternary and quaternary cementitious systems with or without limestone materials provided a passivating layer, with or without acid neutralization capacity, which protected SCC from severe damage in the aggressive sulfuric acid and ammonium sulfate solutions. In contrast to conclusions drawn from the sodium sulfate immersion

  18. AI-2 quorum-sensing inhibitors affect the starvation response and reduce virulence in several Vibrio species, most likely by interfering with LuxPQ.

    Science.gov (United States)

    Brackman, Gilles; Celen, Shari; Baruah, Kartik; Bossier, Peter; Van Calenbergh, Serge; Nelis, Hans J; Coenye, Tom

    2009-12-01

    The increase of disease outbreaks caused by Vibrio species in aquatic organisms as well as in humans, together with the emergence of antibiotic resistance in Vibrio species, has led to a growing interest in alternative disease control measures. Quorum sensing (QS) is a mechanism for regulating microbial gene expression in a cell density-dependent way. While there is good evidence for the involvement of auto-inducer 2 (AI-2)-based interspecies QS in the control of virulence in multiple Vibrio species, only few inhibitors of this system are known. From the screening of a small panel of nucleoside analogues for their ability to disturb AI-2-based QS, an adenosine derivative with a p-methoxyphenylpropionamide moiety at C-3' emerged as a promising hit. Its mechanism of inhibition was elucidated by measuring the effect on bioluminescence in a series of Vibrio harveyi AI-2 QS mutants. Our results indicate that this compound, as well as a truncated analogue lacking the adenine base, block AI-2-based QS without interfering with bacterial growth. The active compounds affected neither the bioluminescence system as such nor the production of AI-2, but most likely interfered with the signal transduction pathway at the level of LuxPQ in V. harveyi. The most active nucleoside analogue (designated LMC-21) was found to reduce the Vibrio species starvation response, to affect biofilm formation in Vibrio anguillarum, Vibrio vulnificus and Vibrio cholerae, to reduce pigment and protease production in V. anguillarum, and to protect gnotobiotic Artemia from V. harveyi-induced mortality.

  19. Chondroitin / dermatan sulfate modification enzymes in zebrafish development.

    Directory of Open Access Journals (Sweden)

    Judith Habicher

    Full Text Available Chondroitin/dermatan sulfate (CS/DS proteoglycans consist of unbranched sulfated polysaccharide chains of repeating GalNAc-GlcA/IdoA disaccharide units, attached to serine residues on specific proteins. The CS/DS proteoglycans are abundant in the extracellular matrix where they have essential functions in tissue development and homeostasis. In this report a phylogenetic analysis of vertebrate genes coding for the enzymes that modify CS/DS is presented. We identify single orthologous genes in the zebrafish genome for the sulfotransferases chst7, chst11, chst13, chst14, chst15 and ust and the epimerase dse. In contrast, two copies were found for mammalian sulfotransferases CHST3 and CHST12 and the epimerase DSEL, named chst3a and chst3b, chst12a and chst12b, dsela and dselb, respectively. Expression of CS/DS modification enzymes is spatially and temporally regulated with a large variation between different genes. We found that CS/DS 4-O-sulfotransferases and 6-O-sulfotransferases as well as CS/DS epimerases show a strong and partly overlapping expression, whereas the expression is restricted for enzymes with ability to synthesize di-sulfated disaccharides. A structural analysis further showed that CS/DS sulfation increases during embryonic development mainly due to synthesis of 4-O-sulfated GalNAc while the proportion of 6-O-sulfated GalNAc increases in later developmental stages. Di-sulfated GalNAc synthesized by Chst15 and 2-O-sulfated GlcA/IdoA synthesized by Ust are rare, in accordance with the restricted expression of these enzymes. We also compared CS/DS composition with that of heparan sulfate (HS. Notably, CS/DS biosynthesis in early zebrafish development is more dynamic than HS biosynthesis. Furthermore, HS contains disaccharides with more than one sulfate group, which are virtually absent in CS/DS.

  20. Effects of sulfate chitosan derivatives on nonalcoholic fatty liver disease

    Science.gov (United States)

    Yu, Mingming; Wang, Yuanhong; Jiang, Tingfu; Lv, Zhihua

    2014-06-01

    Sulfate chitosan derivatives have good solubility and therapeutic effect on the cell model of NAFLD. The aim of this study was to examine the therapeutic effect of sulfate chitosan derivatives on NAFLD. The male Wistar rats were orally fed high fat emulsion and received sulfate chitosan derivatives for 5 weeks to determine the pre-treatment effect of sulfate chitosan derivatives on NAFLD. To evaluate the therapeutic effect of sulfate chitosan derivatives on NAFLD, the rats were orally fed with high concentration emulsion for 5 weeks, followed by sulfate chitosan derivatives for 3 weeks. Histological analysis and biomedical assays showed that sulfate chitosan derivatives can dramatically prevent the development of hepatic steatosis in hepatocyte cells. In animal studies, pre-treatment and treatment with sulfate chitosan derivatives significantly protected against hepatic steatohepatitis induced by high fat diet according to histological analysis. Furthermore, increased TC, ALT, MDA, and LEP in NAFLD were significantly ameliorated by pre-treatment and treatment with sulfate chitosan derivatives. Furthermore, increased TG, AST, and TNF-α in NAFLD were significantly ameliorated by treatment with sulfate chitosan derivatives. Sulfate chitosan derivatives have good pre-treatment and therapeutic effect on NAFLD.

  1. Importance of sulfate radical anion formation and chemistry in heterogeneous OH oxidation of sodium methyl sulfate, the smallest organosulfate

    Science.gov (United States)

    Chung Kwong, Kai; Chim, Man Mei; Davies, James F.; Wilson, Kevin R.; Nin Chan, Man

    2018-02-01

    Organosulfates are important organosulfur compounds present in atmospheric particles. While the abundance, composition, and formation mechanisms of organosulfates have been extensively investigated, it remains unclear how they transform and evolve throughout their atmospheric lifetime. To acquire a fundamental understanding of how organosulfates chemically transform in the atmosphere, this work investigates the heterogeneous OH radical-initiated oxidation of sodium methyl sulfate (CH3SO4Na) droplets, the smallest organosulfate detected in atmospheric particles, using an aerosol flow tube reactor at a high relative humidity (RH) of 85 %. Aerosol mass spectra measured by a soft atmospheric pressure ionization source (direct analysis in real time, DART) coupled with a high-resolution mass spectrometer showed that neither functionalization nor fragmentation products are detected. Instead, the ion signal intensity of the bisulfate ion (HSO4-) has been found to increase significantly after OH oxidation. We postulate that sodium methyl sulfate tends to fragment into a formaldehyde (CH2O) and a sulfate radical anion (SO4 ṡ -) upon OH oxidation. The formaldehyde is likely partitioned back to the gas phase due to its high volatility. The sulfate radical anion, similar to OH radical, can abstract a hydrogen atom from neighboring sodium methyl sulfate to form the bisulfate ion, contributing to the secondary chemistry. Kinetic measurements show that the heterogeneous OH reaction rate constant, k, is (3.79 ± 0.19) × 10-13 cm3 molecule-1 s-1 with an effective OH uptake coefficient, γeff, of 0.17 ± 0.03. While about 40 % of sodium methyl sulfate is being oxidized at the maximum OH exposure (1.27 × 1012 molecule cm-3 s), only a 3 % decrease in particle diameter is observed. This can be attributed to a small fraction of particle mass lost via the formation and volatilization of formaldehyde. Overall, we firstly demonstrate that the heterogeneous OH oxidation of an

  2. Mechanisms of direct inhibition of the respiratory sulfate-reduction pathway by (per)chlorate and nitrate.

    Science.gov (United States)

    Carlson, Hans K; Kuehl, Jennifer V; Hazra, Amrita B; Justice, Nicholas B; Stoeva, Magdalena K; Sczesnak, Andrew; Mullan, Mark R; Iavarone, Anthony T; Engelbrektson, Anna; Price, Morgan N; Deutschbauer, Adam M; Arkin, Adam P; Coates, John D

    2015-06-01

    We investigated perchlorate (ClO(4)(-)) and chlorate (ClO(3)(-)) (collectively (per)chlorate) in comparison with nitrate as potential inhibitors of sulfide (H(2)S) production by mesophilic sulfate-reducing microorganisms (SRMs). We demonstrate the specificity and potency of (per)chlorate as direct SRM inhibitors in both pure cultures and undefined sulfidogenic communities. We demonstrate that (per)chlorate and nitrate are antagonistic inhibitors and resistance is cross-inducible implying that these compounds share at least one common mechanism of resistance. Using tagged-transposon pools we identified genes responsible for sensitivity and resistance in Desulfovibrio alaskensis G20. We found that mutants in Dde_2702 (Rex), a repressor of the central sulfate-reduction pathway were resistant to both (per)chlorate and nitrate. In general, Rex derepresses its regulon in response to increasing intracellular NADH:NAD(+) ratios. In cells in which respiratory sulfate reduction is inhibited, NADH:NAD(+) ratios should increase leading to derepression of the sulfate-reduction pathway. In support of this, in (per)chlorate or nitrate-stressed wild-type G20 we observed higher NADH:NAD(+) ratios, increased transcripts and increased peptide counts for genes in the core Rex regulon. We conclude that one mode of (per)chlorate and nitrate toxicity is as direct inhibitors of the central sulfate-reduction pathway. Our results demonstrate that (per)chlorate are more potent inhibitors than nitrate in both pure cultures and communities, implying that they represent an attractive alternative for controlling sulfidogenesis in industrial ecosystems. Of these, perchlorate offers better application logistics because of its inhibitory potency, solubility, relative chemical stability, low affinity for mineral cations and high mobility in environmental systems.

  3. Chondroitin-4-sulfation negatively regulates axonal guidance and growth

    Science.gov (United States)

    Wang, Hang; Katagiri, Yasuhiro; McCann, Thomas E.; Unsworth, Edward; Goldsmith, Paul; Yu, Zu-Xi; Tan, Fei; Santiago, Lizzie; Mills, Edward M.; Wang, Yu; Symes, Aviva J.; Geller, Herbert M.

    2008-01-01

    Summary Glycosaminoglycan (GAG) side chains endow extracellular matrix proteoglycans with diversity and complexity based upon the length, composition, and charge distribution of the polysaccharide chain. Using cultured primary neurons, we show that specific sulfation in the GAG chains of chondroitin sulfate (CS) mediates neuronal guidance cues and axonal growth inhibition. Chondroitin-4-sulfate (CS-A), but not chondroitin-6-sulfate (CS-C), exhibits a strong negative guidance cue to mouse cerebellar granule neurons. Enzymatic and gene-based manipulations of 4-sulfation in the GAG side chains alter their ability to direct growing axons. Furthermore, 4-sulfated CS GAG chains are rapidly and significantly increased in regions that do not support axonal regeneration proximal to spinal cord lesions in mice. Thus, our findings provide the evidence showing that specific sulfation along the carbohydrate backbone carries instructions to regulate neuronal function. PMID:18768934

  4. Immunotoxicity of copper nanoparticle and copper sulfate in a common Indian earthworm.

    Science.gov (United States)

    Gautam, Arunodaya; Ray, Abhishek; Mukherjee, Soumalya; Das, Santanu; Pal, Kunal; Das, Subhadeep; Karmakar, Parimal; Ray, Mitali; Ray, Sajal

    2018-02-01

    Copper oxide nanoparticles and copper sulfate are established contaminants of water and soil. Metaphire posthuma is a common variety of earthworm distributed in moist soil of Indian subcontinent. Comparative toxicity of copper nanoparticles and copper sulfate were investigated with reference to selected immune associated parameters of earthworm. Total count, phagocytic response, generation of cytotoxic molecules (superoxide anion, nitric oxide), activities of enzymes like phenoloxidase, superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase and total protein of coelomocytes were estimated under the exposures of 100, 500, 1000mg of copper oxide nanoparticles and copper sulfate per kg of soil for 7 and 14 d. A significant decrease in the total coelomocyte count were recorded with maximum depletion as 15.45 ± 2.2 and 12.5 ± 2 × 10 4 cells/ml under the treatment of 1000mg/kg of copper nanoparticles and copper sulfate for 14 d respectively. A significant decrease in generation of nitric oxide and activity of phenoloxidase were recorded upon exposure of both toxins for 7 and 14 d indicating possible decline in cytotoxic status of the organism. A maximum inhibition of superoxide dismutase activity was recorded as 0.083 ± 0.0039 and 0.055 ± 0.0057 unit/mg protein/minute against 1000mg/kg of copper nanoparticles and copper sulfate treatment for 14 d respectively. Activities of catalase and alkaline phosphatase were inhibited by all experimental concentrations of both toxins in the coelomocytes of earthworm. These toxins were recorded to be modifiers of the major immune associated parameters of M. posthuma. Unrestricted contamination of soil by sulfate and oxide nanoparticles of copper may lead to an undesirable shift in the innate immunological status of earthworm leading to a condition of immune compromisation and shrinkage in population density of this species in its natural habitat. This article is the first time report of immunological toxicity of

  5. A thermo-responsive and photo-polymerizable chondroitin sulfate-based hydrogel for 3D printing applications

    NARCIS (Netherlands)

    Abbadessa, A.; Blokzijl, M. M.; Mouser, V. H. M.; Marica, P.; Malda, J.; Hennink, W. E.; Vermonden, T.

    2016-01-01

    The aim ofthis study was to design a hydrogel system based on methacrylated chondroitin sulfate (CSMA) and a thermo-sensitive poly(N-(2-hydroxypropyl) methacrylamide-mono/dilactate)-polyethylene glycol triblock copolymer (M15P10) as a suitable material for additive manufacturing of scaffolds. CSMA

  6. Starvation-associated genome restructuring can lead to reproductive isolation in yeast.

    Directory of Open Access Journals (Sweden)

    Evgueny Kroll

    Full Text Available Knowledge of the mechanisms that lead to reproductive isolation is essential for understanding population structure and speciation. While several models have been advanced to explain post-mating reproductive isolation, experimental data supporting most are indirect. Laboratory investigations of this phenomenon are typically carried out under benign conditions, which result in low rates of genetic change unlikely to initiate reproductive isolation. Previously, we described an experimental system using the yeast Saccharomyces cerevisiae where starvation served as a proxy to any stress that decreases reproduction and/or survivorship. We showed that novel lineages with restructured genomes quickly emerged in starved populations, and that these survivors were more fit than their ancestors when re-starved. Here we show that certain yeast lineages that survive starvation have become reproductively isolated from their ancestor. We further demonstrate that reproductive isolation arises from genomic rearrangements, whose frequency in starving yeast is several orders of magnitude greater than an unstarved control. By contrast, the frequency of point mutations is less than 2-fold greater. In a particular case, we observe that a starved lineage becomes reproductively isolated as a direct result of the stress-related accumulation of a single chromosome. We recapitulate this result by demonstrating that introducing an extra copy of one or several chromosomes into naïve, i.e. unstarved, yeast significantly diminishes their fertility. This type of reproductive barrier, whether arising spontaneously or via genetic manipulation, can be removed by making a lineage euploid for the altered chromosomes. Our model provides direct genetic evidence that reproductive isolation can arise frequently in stressed populations via genome restructuring without the precondition of geographic isolation.

  7. Starvation dynamics of a greedy forager

    Science.gov (United States)

    Bhat, U.; Redner, S.; Bénichou, O.

    2017-07-01

    We investigate the dynamics of a greedy forager that moves by random walking in an environment where each site initially contains one unit of food. Upon encountering a food-containing site, the forager eats all the food there and can subsequently hop an additional S steps without food before starving to death. Upon encountering an empty site, the forager goes hungry and comes one time unit closer to starvation. We investigate the new feature of forager greed; if the forager has a choice between hopping to an empty site or to a food-containing site in its nearest neighborhood, it hops preferentially towards food. If the neighboring sites all contain food or are all empty, the forager hops equiprobably to one of these neighbors. Paradoxically, the lifetime of the forager can depend non-monotonically on greed, and the sense of the non-monotonicity is opposite in one and two dimensions. Even more unexpectedly, the forager lifetime in one dimension is substantially enhanced when the greed is negative; here the forager tends to avoid food in its local neighborhood. We also determine the average amount of food consumed at the instant when the forager starves. We present analytic, heuristic, and numerical results to elucidate these intriguing phenomena.

  8. Tomato strigolactones are derived from carotenoids and their biosynthesis is promoted by phosphate starvation.

    Science.gov (United States)

    López-Ráez, Juan Antonio; Charnikhova, Tatsiana; Gómez-Roldán, Victoria; Matusova, Radoslava; Kohlen, Wouter; De Vos, Ric; Verstappen, Francel; Puech-Pages, Virginie; Bécard, Guillaume; Mulder, Patrick; Bouwmeester, Harro

    2008-01-01

    * Strigolactones are rhizosphere signalling compounds that mediate host location in arbuscular mycorrhizal (AM) fungi and parasitic plants. Here, the regulation of the biosynthesis of strigolactones is studied in tomato (Solanum lycopersicum). * Strigolactone production under phosphate starvation, in the presence of the carotenoid biosynthesis inhibitor fluridone and in the abscisic acid (ABA) mutant notabilis were assessed using a germination bioassay with seeds of Orobanche ramosa; a hyphal branching assay with Gigaspora spp; and by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis. * The root exudates of tomato cv. MoneyMaker induced O. ramosa seed germination and hyphal branching in AM fungi. Phosphate starvation markedly increased, and fluridone strongly decreased, this activity. Exudates of notabilis induced approx. 40% less germination than the wild-type. The LC-MS/MS analysis confirmed that the biological activity and changes therein were due to the presence of several strigolactones; orobanchol, solanacol and two or three didehydro-orobanchol isomers. * These results show that the AM branching factors and parasitic plant germination stimulants in tomato root exudate are strigolactones and that they are biosynthetically derived from carotenoids. The dual activity of these signalling compounds in attracting beneficial AM fungi and detrimental parasitic plants is further strengthened by environmental conditions such as phosphate availability.

  9. Nutrient starvation leading to triglyceride accumulation activates the Entner Doudoroff pathway in Rhodococcus jostii RHA1.

    Science.gov (United States)

    Juarez, Antonio; Villa, Juan A; Lanza, Val F; Lázaro, Beatriz; de la Cruz, Fernando; Alvarez, Héctor M; Moncalián, Gabriel

    2017-02-27

    Rhodococcus jostii RHA1 and other actinobacteria accumulate triglycerides (TAG) under nutrient starvation. This property has an important biotechnological potential in the production of sustainable oils. To gain insight into the metabolic pathways involved in TAG accumulation, we analysed the transcriptome of R jostii RHA1 under nutrient-limiting conditions. We correlate these physiological conditions with significant changes in cell physiology. The main consequence was a global switch from catabolic to anabolic pathways. Interestingly, the Entner-Doudoroff (ED) pathway was upregulated in detriment of the glycolysis or pentose phosphate pathways. ED induction was independent of the carbon source (either gluconate or glucose). Some of the diacylglycerol acyltransferase genes involved in the last step of the Kennedy pathway were also upregulated. A common feature of the promoter region of most upregulated genes was the presence of a consensus binding sequence for the cAMP-dependent CRP regulator. This is the first experimental observation of an ED shift under nutrient starvation conditions. Knowledge of this switch could help in the design of metabolomic approaches to optimize carbon derivation for single cell oil production.

  10. Barium Sulfate

    Science.gov (United States)

    ... uses a computer to put together x-ray images to create cross-sectional or three dimensional pictures of the inside of the body). Barium sulfate is in a class of medications called radiopaque contrast media. It works by coating the esophagus, stomach, or ...

  11. dbl-1/TGF-β and daf-12/NHR Signaling Mediate Cell-Nonautonomous Effects of daf-16/FOXO on Starvation-Induced Developmental Arrest.

    Directory of Open Access Journals (Sweden)

    Rebecca E W Kaplan

    2015-12-01

    Full Text Available Nutrient availability has profound influence on development. In the nematode C. elegans, nutrient availability governs post-embryonic development. L1-stage larvae remain in a state of developmental arrest after hatching until they feed. This "L1 arrest" (or "L1 diapause" is associated with increased stress resistance, supporting starvation survival. Loss of the transcription factor daf-16/FOXO, an effector of insulin/IGF signaling, results in arrest-defective and starvation-sensitive phenotypes. We show that daf-16/FOXO regulates L1 arrest cell-nonautonomously, suggesting that insulin/IGF signaling regulates at least one additional signaling pathway. We used mRNA-seq to identify candidate signaling molecules affected by daf-16/FOXO during L1 arrest. dbl-1/TGF-β, a ligand for the Sma/Mab pathway, daf-12/NHR and daf-36/oxygenase, an upstream component of the daf-12 steroid hormone signaling pathway, were up-regulated during L1 arrest in a daf-16/FOXO mutant. Using genetic epistasis analysis, we show that dbl-1/TGF-β and daf-12/NHR steroid hormone signaling pathways are required for the daf-16/FOXO arrest-defective phenotype, suggesting that daf-16/FOXO represses dbl-1/TGF-β, daf-12/NHR and daf-36/oxygenase. The dbl-1/TGF-β and daf-12/NHR pathways have not previously been shown to affect L1 development, but we found that disruption of these pathways delayed L1 development in fed larvae, consistent with these pathways promoting development in starved daf-16/FOXO mutants. Though the dbl-1/TGF-β and daf-12/NHR pathways are epistatic to daf-16/FOXO for the arrest-defective phenotype, disruption of these pathways does not suppress starvation sensitivity of daf-16/FOXO mutants. This observation uncouples starvation survival from developmental arrest, indicating that DAF-16/FOXO targets distinct effectors for each phenotype and revealing that inappropriate development during starvation does not cause the early demise of daf-16/FOXO mutants. Overall

  12. dbl-1/TGF-β and daf-12/NHR Signaling Mediate Cell-Nonautonomous Effects of daf-16/FOXO on Starvation-Induced Developmental Arrest.

    Science.gov (United States)

    Kaplan, Rebecca E W; Chen, Yutao; Moore, Brad T; Jordan, James M; Maxwell, Colin S; Schindler, Adam J; Baugh, L Ryan

    2015-12-01

    Nutrient availability has profound influence on development. In the nematode C. elegans, nutrient availability governs post-embryonic development. L1-stage larvae remain in a state of developmental arrest after hatching until they feed. This "L1 arrest" (or "L1 diapause") is associated with increased stress resistance, supporting starvation survival. Loss of the transcription factor daf-16/FOXO, an effector of insulin/IGF signaling, results in arrest-defective and starvation-sensitive phenotypes. We show that daf-16/FOXO regulates L1 arrest cell-nonautonomously, suggesting that insulin/IGF signaling regulates at least one additional signaling pathway. We used mRNA-seq to identify candidate signaling molecules affected by daf-16/FOXO during L1 arrest. dbl-1/TGF-β, a ligand for the Sma/Mab pathway, daf-12/NHR and daf-36/oxygenase, an upstream component of the daf-12 steroid hormone signaling pathway, were up-regulated during L1 arrest in a daf-16/FOXO mutant. Using genetic epistasis analysis, we show that dbl-1/TGF-β and daf-12/NHR steroid hormone signaling pathways are required for the daf-16/FOXO arrest-defective phenotype, suggesting that daf-16/FOXO represses dbl-1/TGF-β, daf-12/NHR and daf-36/oxygenase. The dbl-1/TGF-β and daf-12/NHR pathways have not previously been shown to affect L1 development, but we found that disruption of these pathways delayed L1 development in fed larvae, consistent with these pathways promoting development in starved daf-16/FOXO mutants. Though the dbl-1/TGF-β and daf-12/NHR pathways are epistatic to daf-16/FOXO for the arrest-defective phenotype, disruption of these pathways does not suppress starvation sensitivity of daf-16/FOXO mutants. This observation uncouples starvation survival from developmental arrest, indicating that DAF-16/FOXO targets distinct effectors for each phenotype and revealing that inappropriate development during starvation does not cause the early demise of daf-16/FOXO mutants. Overall, this study shows

  13. Conformational Flexibility Enables the Function of a BECN1 Region Essential for Starvation-Mediated Autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Yang; Ramanathan, Arvind; Glover, Karen; Stanley, Christopher; Sanishvili, Ruslan; Chakravarthy, Srinivas; Yang, Zhongyu; Colbert, Christopher L.; Sinha, Sangita C.

    2016-04-05

    BECN1 is essential for autophagy, a critical eukaryotic cellular homeostasis pathway. Here we delineate a highly conserved BECN1 domain located between previously characterized BH3 and coiled-coil domains and elucidate its structure and role in autophagy. The 2.0 angstrom sulfur-single-wavelength anomalous dispersion X-ray crystal structure of this domain demonstrates that its N-terminal half is unstructured while its C-terminal half is helical; hence, we name it the flexible helical domain (FHD). Circular dichroism spectroscopy, double electron electron resonance electron paramagnetic resonance, and small-angle X-ray scattering (SAXS) analyses confirm that the FHD is partially disordered, even in the context of adjacent BECN1 domains. Molecular dynamic simulations fitted to SAXS data indicate that the FHD transiently samples more helical conformations. FHD helicity increases in 2,2,2-trifluoroethanol, suggesting it may become more helical upon binding. Lastly, cellular studies show that conserved FHD residues are required for starvation-induced autophagy. Thus, the FHD likely undergoes a binding-associated disorder to-helix transition, and conserved residues critical for this interaction are essential for starvation-induced autophagy.

  14. Cotard’s Syndrome: Two Cases of Self-Starvation

    Directory of Open Access Journals (Sweden)

    Bruno Gonçalves Teixeira

    2015-11-01

    Full Text Available Background: Cotard´s syndrome is a relatively rare condition characterized by various degrees of nihilist delusions, often in the form of self-negation. Aims: To report two cases of Cotard’s syndrome associated with self-starvation and to review the concept and clinical features of the condition. Methods: Two clinical cases of the syndrome were obtained and a literature review of the theme was shortly surveyed. Results and Conclusions: The first case is about a woman who believed that her esophagus and stomach were glued. She was treated with sertraline, mirtazapine and risperidone with good results. The second case describes a man who believed his throat was burnt and he had no internal organs. He was treated with clomipramine and risperidone showing great improvement. This syndrome is a nosological and clinical entity that should not be forgotten. It is essential to provide an urgent and adequate therapeutic approach to these patients.

  15. Metabolic interactions in methanogenic and sulfate-reducing bioreactors.

    Science.gov (United States)

    Stams, A J M; Plugge, C M; de Bok, F A M; van Houten, B H G W; Lens, P; Dijkman, H; Weijma, J

    2005-01-01

    In environments where the amount of electron acceptors is insufficient for complete breakdown of organic matter, methane is formed as the major reduced end product. In such methanogenic environments organic acids are degraded by syntrophic consortia of acetogenic bacteria and methanogenic archaea. Hydrogen consumption by methanogens is essential for acetogenic bacteria to convert organic acids to acetate and hydrogen. Several syntrophic cocultures growing on propionate and butyrate have been described. These syntrophic fatty acid-degrading consortia are affected by the presence of sulfate. When sulfate is present sulfate-reducing bacteria compete with methanogenic archaea for hydrogen and acetate, and with acetogenic bacteria for propionate and butyrate. Sulfate-reducing bacteria easily outcompete methanogens for hydrogen, but the presence of acetate as carbon source may influence the outcome of the competition. By contrast, acetoclastic methanogens can compete reasonably well with acetate-degrading sulfate reducers. Sulfate-reducing bacteria grow much faster on propionate and butyrate than syntrophic consortia.

  16. Sulfated cellulose thin films with antithrombin affinity

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available Cellulose thin films were chemically modified by in situ sulfation to produce surfaces with anticoagulant characteristics. Two celluloses differing in their degree of polymerization (DP: CEL I (DP 215–240 and CEL II (DP 1300–1400 were tethered to maleic anhydride copolymer (MA layers and subsequently exposed to SO3•NMe3 solutions at elevated temperature. The impact of the resulting sulfation on the physicochemical properties of the cellulose films was investigated with respect to film thickness, atomic composition, wettability and roughness. The sulfation was optimized to gain a maximal surface concentration of sulfate groups. The scavenging of antithrombin (AT by the surfaces was determined to conclude on their potential anticoagulant properties.

  17. Direct sulfation of limestone based on oxy-fuel combustion technology

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.M.; Zhao, C.S.; Liu, S.T.; Wang, C.B. [North China Electric Power University, Baoding (China)

    2009-10-15

    With limestone as the sorbent, the sulfation reaction can proceed via two different routes depending on whether calcination of the limestone takes place under the given reaction conditions. The direct sulfation reaction is defined as the sulfation reaction between sulfur dioxide (SO{sub 2}) and limestone in an uncalcined state. This reaction, based on oxyfuel combustion technology, was studied by thermogravimetric analysis. Surface morphologies of the limestone particles after sulfation were examined by a scanning electron microscope. Results show that there are more pores or gaps in the product layer formed by direct sulfation of limestone than by indirect sulfation, which can be attributed to the generation of carbon dioxide (CO{sub 2}) at a reaction interface. Compared with indirect sulfation, direct sulfation of limestone can yield much higher conversion and has a much higher reaction rate. For direct sulfation, the greater porosity in the product layer greatly reduces the solid-state ion diffusion distance, resulting in a higher reaction rate and higher conversion.

  18. The significance of translation regulation in the stress response

    OpenAIRE

    Picard, Flora; Loubière, Pascal; Girbal, Laurence; Bousquet, Muriel

    2013-01-01

    Background: The stress response in bacteria involves the multistage control of gene expression but is not entirely understood. To identify the translational response of bacteria in stress conditions and assess its contribution to the regulation of gene expression, the translational states of all mRNAs were compared under optimal growth condition and during nutrient (isoleucine) starvation. Results: A genome-scale study of the translational response to nutritional limitation was performed in t...

  19. Chinese hamster ovary cell mutants defective in heparan sulfate biosynthesis

    International Nuclear Information System (INIS)

    Bame, K.J.; Kiser, C.S.; Esko, J.D.

    1987-01-01

    The authors have isolated Chinese hamster ovary cell mutants defective in proteoglycan synthesis by radiographic screening for cells unable to incorporate 35 SO 4 into acid-precipitable material. Some mutants did not incorporate 35 SO 4 into acid-precipitable material, whereas others incorporated about 3-fold less radioactivity. HPLC anion exchange chromatographic analysis of radiolabelled glycosaminoglycans isolated from these mutants revealed many are defective in heparan sulfate biosynthesis. Mutants 803 and 677 do not synthesize heparan sulfate, although they produce chondroitin sulfate: strain 803 makes chondroitin sulfate normally, whereas 677 overaccumulates chondroitin sulfate by a factor of three. These mutants fall into the same complementation group, suggesting that the mutations are allelic. A second group of heparan sulfate biosynthetic mutants, consisting of cell lines 625, 668 and 679, produce undersulfated heparan sulfate and normal chondroitin sulfate. Treatment of the chains with nitrous acid should determine the position of the sulfate groups along the chain. These mutants may define a complementation group that is defective in the enzymes which modify the heparan sulfate chain. To increase the authors repertoire of heparan sulfate mutants, they are presently developing an in situ enzyme assay to screen colonies replica plated on filter discs for sulfotransferase defects

  20. A thermo-responsive and photo-polymerizable chondroitin sulfate-based hydrogel for 3D printing applications

    NARCIS (Netherlands)

    Abbadessa, A|info:eu-repo/dai/nl/369480376; Blokzijl, M M; Mouser, V H M; Marica, P; Malda, J|info:eu-repo/dai/nl/412461099; Hennink, W E|info:eu-repo/dai/nl/070880409; Vermonden, T|info:eu-repo/dai/nl/275124517

    2016-01-01

    The aim of this study was to design a hydrogel system based on methacrylated chondroitin sulfate (CSMA) and a thermo-sensitive poly(N-(2-hydroxypropyl) methacrylamide-mono/dilactate)-polyethylene glycol triblock copolymer (M15P10) as a suitable material for additive manufacturing of scaffolds. CSMA

  1. Effects of prolonged drought on stem non-structural carbohydrates content and post-drought hydraulic recovery in Laurus nobilis L.: The possible link between carbon starvation and hydraulic failure.

    Science.gov (United States)

    Trifilò, Patrizia; Casolo, Valentino; Raimondo, Fabio; Petrussa, Elisa; Boscutti, Francesco; Lo Gullo, Maria Assunta; Nardini, Andrea

    2017-11-01

    Drought-induced tree decline is a complex event, and recent hypotheses suggest that hydraulic failure and carbon starvation are co-responsible for this process. We tested the possible role of non-structural carbohydrates (NSC) content on post-drought hydraulic recovery, to verify the hypothesis that embolism reversal represents a mechanistic link between carbon starvation and stem hydraulics. Measurements were performed in laurel plants subjected to similar water stress levels either over short or long term, to induce comparable embolism levels. Plants subjected to mild and prolonged water shortage (S) showed reduced growth, adjustment of turgor loss point driven by changes in both osmotic potential at full turgor and bulk modulus of elasticity, a lower content of soluble NSC and a higher content of starch with respect to control (C) plants. Moreover, S plants showed a lower ability to recover from xylem embolism than C plants, even after irrigation. Our data suggest that plant carbon status might indirectly influence plant performance during and after drought via effects on xylem hydraulic functioning, supporting the view of a possible mechanistic link between the two processes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. Phage adsorption and lytic propagation in Lactobacillus plantarum: Could host cell starvation affect them?

    OpenAIRE

    Briggiler Marc?, Mari?ngeles; Reinheimer, Jorge; Quiberoni, Andrea

    2015-01-01

    Background Bacteriophages constitute a great threat to the activity of lactic acid bacteria used in industrial processes. Several factors can influence the infection cycle of bacteriophages. That is the case of the physiological state of host cells, which could produce inhibition or delay of the phage infection process. In the present work, the influence of Lactobacillus plantarum host cell starvation on phage B1 adsorption and propagation was investigated. Result First, cell growth kinetics ...

  3. Global source attribution of sulfate aerosol and its radiative forcing

    Science.gov (United States)

    Yang, Y.; Wang, H.; Smith, S.; Easter, R. C.; Ma, P. L.; Qian, Y.; Li, C.; Yu, H.; Rasch, P. J.

    2017-12-01

    Sulfate is an important aerosol that poses health risks and influences climate. Due to long-range atmospheric transport, local sulfate pollution could result from intercontinental influences, making domestic efforts of improving air quality inefficient. Accurate understanding of source attribution of sulfate and its radiative forcing is important for both regional air quality improvement and global climate mitigation. In this study, for the first time, a sulfur source-tagging capability is implemented in the Community Atmosphere Model (CAM5) to quantify the global source-receptor relationships of sulfate and its direct and indirect radiative forcing (DRF and IRF). Near-surface sulfate concentrations are mostly contributed by local emissions in regions with high emissions, while over regions with relatively low SO2 emissions, the near-surface sulfate is primarily attributed to non-local sources from long-range transport. The export of SO2 and sulfate from Europe contributes 20% of sulfate concentrations over North Africa, Russia and Central Asia. Sources from the Middle East account for 20% of sulfate over North Africa, Southern Africa and Central Asia in winter and autumn, and 20% over South Asia in spring. East Asia accounts for about 50% of sulfate over Southeast Asia in winter and autumn, 15% over Russia in summer, and 10% over North America in spring. South Asia contributes to 25% of sulfate over Southeast Asia in spring. Lifetime of aerosols, together with regional export, is found to determine regional air quality. The simulated global total sulfate DRF is -0.42 W m-2, with 75% contributed by anthropogenic sulfate and 25% contributed by natural sulfate. In the Southern Hemisphere tropics, dimethyl sulfide (DMS) contributes the most to the total DRF. East Asia has the largest contribution of 20-30% over the Northern Hemisphere mid- and high-latitudes. A 20% perturbation of sulfate and its precursor emissions gives a sulfate IRF of -0.44 W m-2. DMS has the

  4. Incorporation of 35S-sulfate and 3H-glucosamine into heparan and chondroitin sulfates during the cell cycle of B16-F10 cells

    International Nuclear Information System (INIS)

    Blair, O.C.; Sartorelli, A.C.

    1984-01-01

    Changes in glycosaminoglycan composition occurring during the cell cycle were determined in B16-F10 cells sorted flow cytometrically with respect to DNA content. Incorporation of 35 S-sulfate into heparan sulfate and chondroitin sulfate of unsorted and G1,S, and G2 +M sorted cells was determined following chondroitinase ABC or nitrous acid treatment; the incorporation into surface material was measured as the difference between the radioactivity of control and trypsin-treated cells. Incorporation of 35 S-sulfate and 3 H-glucosamine into cetyl pyridinium chloride (CPC)-precipitable material was characterized before and after chondroitinase or nitrous acid treatment by Sephadex G50 chromatography. Long-term (48 h) and short-term (1 h) labeling studies demonstrate that (a) the amount of total cellular chondroitin sulfate is greater than that of heparan sulfate, with larger amounts of unsulfated heparan than chondroitin being present; (b) the rate of turnover of heparan sulfate is greater than that of chondroitin sulfate; (c) greatest short-term incorporation of 3H-glucosamine into CPC-precipitable material occurs during S phase; and (d) the rate of turnover of both heparan sulfate and chondroitin sulfate is decreased in S phase relative to G1 and G2 + M

  5. Purification, structural characterization and antiproliferative properties of chondroitin sulfate/dermatan sulfate from tunisian fish skins.

    Science.gov (United States)

    Krichen, Fatma; Volpi, Nicola; Sila, Assaâd; Maccari, Francesca; Mantovani, Veronica; Galeotti, Fabio; Ellouz-Chaabouni, Semia; Bougatef, Ali

    2017-02-01

    Chondroitin sulfate/dermatan sulfate GAGs were extracted and purified from the skins of grey triggerfish (GTSG) and smooth hound (SHSG). The disaccharide composition produced by chondroitinase ABC treatment showed the presence of nonsulfated disaccharide, monosulfated disaccharides ΔDi6S and ΔDi4S, and disulfated disaccharides in different percentages. In particular, the nonsulfated disaccharide ΔDi0S of GTSG and SHSG were 3.5% and 5.5%, respectively, while monosulfated disaccharides ΔDi6S and ΔDi4S were evaluated to be 18.2%, 59% and 14.6%, 47.0%, respectively. Capillary elecrophoresis analysis of GTSG and SHSG contained 99.2% and 95.4% of chondroitin sulfate/dermatan sulfate, respectively. PAGE analysis showed a GTSG and SHSG having molecular masses with average values of 41.72KDa and 23.8KDa, respectively. HCT116 cell proliferation was inhibited (p<0.05) by 70.6% and 72.65% at 200μg/mL of GTSG and SHSG respectively. Both GTSG and SHSG demonstrated promising antiproliferative potential, which may be used as a novel, effective agent. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Importance of sulfate radical anion formation and chemistry in heterogeneous OH oxidation of sodium methyl sulfate, the smallest organosulfate

    Directory of Open Access Journals (Sweden)

    K. C. Kwong

    2018-02-01

    Full Text Available Organosulfates are important organosulfur compounds present in atmospheric particles. While the abundance, composition, and formation mechanisms of organosulfates have been extensively investigated, it remains unclear how they transform and evolve throughout their atmospheric lifetime. To acquire a fundamental understanding of how organosulfates chemically transform in the atmosphere, this work investigates the heterogeneous OH radical-initiated oxidation of sodium methyl sulfate (CH3SO4Na droplets, the smallest organosulfate detected in atmospheric particles, using an aerosol flow tube reactor at a high relative humidity (RH of 85 %. Aerosol mass spectra measured by a soft atmospheric pressure ionization source (direct analysis in real time, DART coupled with a high-resolution mass spectrometer showed that neither functionalization nor fragmentation products are detected. Instead, the ion signal intensity of the bisulfate ion (HSO4− has been found to increase significantly after OH oxidation. We postulate that sodium methyl sulfate tends to fragment into a formaldehyde (CH2O and a sulfate radical anion (SO4 ⋅ − upon OH oxidation. The formaldehyde is likely partitioned back to the gas phase due to its high volatility. The sulfate radical anion, similar to OH radical, can abstract a hydrogen atom from neighboring sodium methyl sulfate to form the bisulfate ion, contributing to the secondary chemistry. Kinetic measurements show that the heterogeneous OH reaction rate constant, k, is (3.79 ± 0.19  ×  10−13 cm3 molecule−1 s−1 with an effective OH uptake coefficient, γeff, of 0.17 ± 0.03. While about 40 % of sodium methyl sulfate is being oxidized at the maximum OH exposure (1.27  ×  1012 molecule cm−3 s, only a 3 % decrease in particle diameter is observed. This can be attributed to a small fraction of particle mass lost via the formation and volatilization of formaldehyde. Overall, we

  7. Experimental study of cell reversal of a high temperature polymer electrolyte membrane fuel cell caused by H2 starvation

    DEFF Research Database (Denmark)

    Zhou, Fan; Andreasen, Søren Juhl; Kær, Søren Knudsen

    2015-01-01

    Operation under fuel starvation has been proved to be harmful to the fuel cell by causing severe and irreversible degradation. To characterize the behaviors of the high temperature PEM fuel cell under fuel starvation conditions, the cell voltage and local current density is measured simultaneously...... under different H2 stoichiometries below 1.0 and at different current loads. The experimental results show that the cell voltage decreases promptly when the H2 stoichiometry decreases to below 1.0. Negative cell voltage can be observed which indicates cell reversal. The local current density starts...... to diverge when the cell voltage decreases. In the H2 upstream regions the current densities show an increasing trend, while those in the H2 downstream regions show a decreasing trend. Consequently, the current density distribution becomes very uneven. The current density is the highest in the upstream...

  8. Transcriptional responses of Medicago truncatula upon sulfur deficiency stress and arbuscular mycorrhizal symbios

    Directory of Open Access Journals (Sweden)

    Daniel eWipf

    2014-12-01

    Full Text Available Sulfur plays an essential role in plants’ growth and development and in their response to various abiotic and biotic stresses despite its leachability and its very low abundance in the only form that plant roots can uptake (sulfate. It is part of amino acids, glutathione (GSH, thiols of proteins and peptides, membrane sulfolipids, cell walls and secondary products, so reduced availability can drastically alter plant growth and development. The nutritional benefits of symbiotic interactions can help the plant in case of S deficiency. In particular the arbuscular mycorrhizal (AM interaction improves N, P and S plant nutrition, but the mechanisms behind these exchanges are not fully known yet. Although the transcriptional changes in the leguminous model plant Medicago truncatula have been already assessed in several biotic and/or abiotic conditions, S deficiency has not been considered so far. The aim of this work is to get a first overview on S-deficiency responses in the leaf and root tissues of plants interacting with the AM fungus Rhizophagus irregularis.Several hundred genes displayed significantly different transcript accumulation levels. Annotation and GO ID association were used to identify biological processes and molecular functions affected by sulfur starvation. Beside the beneficial effects of AM interaction, plants were greatly affected by the nutritional status, showing various differences in their transcriptomic footprints. Several pathways in which S plays an important role appeared to be differentially affected according to mycorrhizal status, with a generally reduced responsiveness to S deficiency in mycorrhized plants.

  9. Low levels of H2S may replace sulfate as sulfur source in sulfate-deprived onion

    NARCIS (Netherlands)

    Durenkamp, Mark; De Kok, LJ

    2005-01-01

    Onion (Allium cepa L.) was exposed to low levels of H2S in order to investigate to what extent H2S could be used as a sulfur source for growth under sulfate-deprived conditions. Sulfate deprivation for a two-week period resulted in a decreased biomass production of the shoot, a subsequently

  10. Sulfates on Mars: TES Observations and Thermal Inertia Data

    Science.gov (United States)

    Cooper, C. D.; Mustard, J. F.

    2001-05-01

    The high resolution thermal emission spectra returned by the TES spectrometer on the MGS spacecraft have allowed the mapping of a variety of minerals and rock types by different sets of researchers. Recently, we have used a linear deconvolution approach to compare sulfate-palagonite soil mixtures created in the laboratory with Martian surface spectra. This approach showed that a number of areas on Mars have spectral properties that match those of sulfate-cemented soils (but neither loose powder mixtures of sulfates and soils nor sand-sized grains of disaggregated crusted soils). These features do not appear to be caused by atmospheric or instrumental effects and are thus believed to be related to surface composition and texture. The distribution and physical state of sulfate are important pieces of information for interpreting surface processes on Mars. A number of different mechanisms could have deposited sulfate in surface layers. Some of these include evaporation of standing bodies of water, aerosol deposition of volcanic gases, hydrothermal alteration from groundwater, and in situ interaction between the atmosphere and soil. The areas on Mars with cemented sulfate signatures are spread across a wide range of elevations and are generally large in spatial scale. Some of the areas are associated with volcanic regions, but many are in dark red plains that have previously been interpreted as duricrust deposits. Our current work compares the distribution of sulfate-cemented soils as mapped by the spectral deconvolution approach with thermal inertia maps produced from both Viking and MGS-TES. Duricrust regions, interpreted from intermediate thermal inertia values, are large regions thought to be sulfate-cemented soils similar to coherent, sulfate-rich materials seen at the Viking lander sites. Our observations of apparent regions of cemented sulfate are also large in spatial extent. This scale information is important for evaluating formation mechanisms for the

  11. Development of affinity-based delivery of NGF from a chondroitin sulfate biomaterial.

    Science.gov (United States)

    Butterfield, Karen Chao; Conovaloff, Aaron W; Panitch, Alyssa

    2011-01-01

    Chondroitin sulfate is a major component of the extracellular matrix in both the central and peripheral nervous systems. Chondroitin sulfate is upregulated at injury, thus methods to promote neurite extension through chondroitin sulfate-rich matrices and synthetic scaffolds are needed. We describe the use of both chondroitin sulfate and a novel chondroitin sulfate-binding peptide to control the release of nerve growth factor. Interestingly, the novel chondroitin sulfate-binding peptide enhances the controlled release properties of the chondroitin sulfate gels. While introduction of chondroitin sulfate into a scaffold inhibits primary cortical outgrowth, the combination of chondroitin sulfate, chondroitin sulfate-binding peptide and nerve growth factor promotes primary cortical neurite outgrowth in chondroitin sulfate gels.

  12. Removal of Sulfate Ion From AN-107 by Evaporation

    International Nuclear Information System (INIS)

    GJ Lumetta; GS Klinger; DE Kurath; RL Sell; LP Darnell; LR Greenwood; CZ Soderquist; MJ Steele; MW Urie; JJ Wagner

    2000-01-01

    Hanford low-activity waste solutions contain sulfate, which can cause accelerated corrosion of the vitrification melter and unacceptable operating conditions. A method is needed to selectively separate sulfate from the waste. An experiment was conducted to evaluate evaporation for removing sulfate ion from Tank AN-107 low-activity waste. Two evaporation steps were performed. In the first step, the volume was reduced by 55% while in the second step, the liquid volume was reduced another 22%. Analysis of the solids precipitated during these evaporations revealed that large amounts of sodium nitrate and nitrite co-precipitated with sodium sulfate. Many other waste components precipitated as well. It can be concluded that sulfate removal by precipitation is not selective, and thus, evaporation is not a viable option for removing sulfate from the AN-107 liquid

  13. Xyloside-primed Chondroitin Sulfate/Dermatan Sulfate from Breast Carcinoma Cells with a Defined Disaccharide Composition Has Cytotoxic Effects in Vitro.

    Science.gov (United States)

    Persson, Andrea; Tykesson, Emil; Westergren-Thorsson, Gunilla; Malmström, Anders; Ellervik, Ulf; Mani, Katrin

    2016-07-08

    We previously reported that the xyloside 2-(6-hydroxynaphthyl) β-d-xylopyranoside (XylNapOH), in contrast to 2-naphthyl β-d-xylopyranoside (XylNap), specifically reduces tumor growth both in vitro and in vivo Although there are indications that this could be mediated by the xyloside-primed glycosaminoglycans (GAGs) and that these differ in composition depending on xyloside and cell type, detailed knowledge regarding a structure-function relationship is lacking. In this study we isolated XylNapOH- and XylNap-primed GAGs from a breast carcinoma cell line, HCC70, and a breast fibroblast cell line, CCD-1095Sk, and demonstrated that both XylNapOH- and XylNap-primed chondroitin sulfate/dermatan sulfate GAGs derived from HCC70 cells had a cytotoxic effect on HCC70 cells and CCD-1095Sk cells. The cytotoxic effect appeared to be mediated by induction of apoptosis and was inhibited in a concentration-dependent manner by the XylNap-primed heparan sulfate GAGs. In contrast, neither the chondroitin sulfate/dermatan sulfate nor the heparan sulfate derived from CCD-1095Sk cells primed on XylNapOH or XylNap had any effect on the growth of HCC70 cells or CCD-105Sk cells. These observations were related to the disaccharide composition of the XylNapOH- and XylNap-primed GAGs, which differed between the two cell lines but was similar when the GAGs were derived from the same cell line. To our knowledge this is the first report on cytotoxic effects mediated by chondroitin sulfate/dermatan sulfate. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Formation of the natural sulfate aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Kerminen, V M; Hillamo, R; Maekinen, M; Virkkula, A; Maekelae, T; Pakkanen, T [Helsinki Univ. (Finland). Dept. of Physics

    1997-12-31

    Anthropogenic sulfate aerosol, together with particles from biomass burning, may significantly reduce the climatic warming due to man-made greenhouse gases. The radiative forcing of aerosol particles is based on their ability to scatter and absorb solar radiation (direct effect), and on their influences on cloud albedos and lifetimes (indirect effect). The direct aerosol effect depends strongly on the size, number and chemical composition of particles, being greatest for particles of 0.1-1 {mu}m in diameter. The indirect aerosol effect is dictated by the number of particles being able to act as cloud condensation nuclei (CCN). For sulfate particles, the minimum CCN size in tropospheric clouds is of the order of 0.05-0.2 {mu}m. To improve aerosol parameterizations in future climate models, it is required that (1) both primary and secondary sources of various particle types will be characterized at a greater accuracy, and (2) the influences of various atmospheric processes on the spatial and temporal distribution of these particles and their physico-chemical properties are known much better than at the present. In estimating the climatic forcing due to the sulfate particles, one of the major problems is to distinguish between sulfur from anthropogenic sources and that of natural origin. Global emissions of biogenic and anthropogenic sulfate pre-cursors are comparable in magnitude, but over regional scales either of these two source types may dominate. The current presentation is devoted to discussing the natural sulfate aerosol, including the formation of sulfur-derived particles in the marine environment, and the use of particulate methanesulfonic acid (MSA) as a tracer for the natural sulfate

  15. Formation of the natural sulfate aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Kerminen, V.M.; Hillamo, R.; Maekinen, M.; Virkkula, A.; Maekelae, T.; Pakkanen, T. [Helsinki Univ. (Finland). Dept. of Physics

    1996-12-31

    Anthropogenic sulfate aerosol, together with particles from biomass burning, may significantly reduce the climatic warming due to man-made greenhouse gases. The radiative forcing of aerosol particles is based on their ability to scatter and absorb solar radiation (direct effect), and on their influences on cloud albedos and lifetimes (indirect effect). The direct aerosol effect depends strongly on the size, number and chemical composition of particles, being greatest for particles of 0.1-1 {mu}m in diameter. The indirect aerosol effect is dictated by the number of particles being able to act as cloud condensation nuclei (CCN). For sulfate particles, the minimum CCN size in tropospheric clouds is of the order of 0.05-0.2 {mu}m. To improve aerosol parameterizations in future climate models, it is required that (1) both primary and secondary sources of various particle types will be characterized at a greater accuracy, and (2) the influences of various atmospheric processes on the spatial and temporal distribution of these particles and their physico-chemical properties are known much better than at the present. In estimating the climatic forcing due to the sulfate particles, one of the major problems is to distinguish between sulfur from anthropogenic sources and that of natural origin. Global emissions of biogenic and anthropogenic sulfate pre-cursors are comparable in magnitude, but over regional scales either of these two source types may dominate. The current presentation is devoted to discussing the natural sulfate aerosol, including the formation of sulfur-derived particles in the marine environment, and the use of particulate methanesulfonic acid (MSA) as a tracer for the natural sulfate

  16. Survival of pathogenic bacteria under nutrient starvation conditions. [aboard orbiting space stations

    Science.gov (United States)

    Boyle, Michael; Ford, Tim; Mitchell, Ralph; Maki, James

    1990-01-01

    The survival of opportunistic pathogenic microorganisms in water, under nutrient-limiting conditions, has been investigated in order to ascertain whether human pathogens can survive within a water-distribution system of the kind proposed for the NASA Space Station. Cultures of a strain of pseudomonas aeruginosa and two strains of staphylococcus aureus were incubated at 10, 25, or 37 C, and samples at 1 day, 1 week, 1 month, and six weeks. While neither of the staphylococcus strains tested were detected after 1 week of starvation, the pseudomonas strain can survive in deionized water at all three temperatures.

  17. Performance of CSTR-EGSB-SBR system for treating sulfate-rich cellulosic ethanol wastewater and microbial community analysis.

    Science.gov (United States)

    Shan, Lili; Zhang, Zhaohan; Yu, Yanling; Ambuchi, John Justo; Feng, Yujie

    2017-06-01

    Performance and microbial community composition were evaluated in a two-phase anaerobic and aerobic system treating sulfate-rich cellulosic ethanol wastewater (CEW). The system was operated at five different chemical oxygen demand (COD)/SO 4 2- ratios (63.8, 26.3, 17.8, 13.7, and 10.7). Stable performance was obtained for total COD removal efficiency (94.5%), sulfate removal (89.3%), and methane production rate (11.5 L/day) at an organic loading rate of 32.4 kg COD/(m 3 ·day). The acidogenic reactor made a positive contribution to net VFAs production (2318.1 mg/L) and sulfate removal (60.9%). Acidogenic bacteria (Megasphaera, Parabacteroides, unclassified Ruminococcaceae spp., and Prevotella) and sulfate-reducing bacteria (Butyrivibrio, Megasphaera) were rich in the acidogenic reactor. In the methanogenic reactor, high diversity of microorganisms corresponded with a COD removal contribution of 83.2%. Moreover, methanogens (Methanosaeta) were predominant, suggesting that these organisms played an important role in the acetotrophic methanogenesis pathway. The dominant aerobic bacteria (Truepera) appeared to have been responsible for the COD removal of the SBR. These results indicate that dividing the sulfate reduction process could effectively minimize sulfide toxicity, which is important for the successful operation of system treating sulfate-rich CEW.

  18. ROLE OF TYROSINE-SULFATED PROTEINS IN RETINAL STRUCTURE AND FUNCTION

    Science.gov (United States)

    Kanan, Y.; Al-Ubaidi, M.R.

    2014-01-01

    The extracellular matrix (ECM) plays a significant role in cellular and retinal health. The study of retinal tyrosine-sulfated proteins is an important first step toward understanding the role of ECM in retinal health and diseases. These secreted proteins are members of the retinal ECM. Tyrosine sulfation was shown to be necessary for the development of proper retinal structure and function. The importance of tyrosine sulfation is further demonstrated by the evolutionary presence of tyrosylprotein sulfotransferases, enzymes that catalyze proteins’ tyrosine sulfation, and the compensatory abilities of these enzymes. Research has identified four tyrosine-sulfated retinal proteins: fibulin 2, vitronectin, complement factor H (CFH), and opticin. Vitronectin and CFH regulate the activation of the complement system and are involved in the etiology of some cases of age-related macular degeneration. Analysis of the role of tyrosine sulfation in fibulin function showed that sulfation influences the protein's ability to regulate growth and migration. Although opticin was recently shown to exhibit anti-angiogenic properties, it is not yet determined what role sulfation plays in that function. Future studies focusing on identifying all of the tyrosine-sulfated retinal proteins would be instrumental in determining the impact of sulfation on retinal protein function in retinal homeostasis and diseases. PMID:25819460

  19. A novel chondroitin sulfate hydrogel for nerve repair

    Science.gov (United States)

    Conovaloff, Aaron William

    Brachial plexus injuries affect numerous patients every year, with very debilitating results. The majority of these cases are very severe, and involve damage to the nerve roots. To date, repair strategies for these injuries address only gross tissue damage, but do not supply cells with adequate regeneration signals. As a result, functional recovery is often severely lacking. Therefore, a chondroitin sulfate hydrogel that delivers neurotrophic signals to damaged neurons is proposed as a scaffold to support nerve root regeneration. Capillary electrophoresis studies revealed that chondroitin sulfate can physically bind with a variety of neurotrophic factors, and cultures of chick dorsal root ganglia demonstrated robust neurite outgrowth in chondroitin sulfate hydrogels. Outgrowth in chondroitin sulfate gels was greater than that observed in control gels of hyaluronic acid. Furthermore, the chondroitin sulfate hydrogel's binding activity with nerve growth factor could be enhanced by incorporation of a synthetic bioactive peptide, as revealed by fluorescence recovery after photobleaching. This enhanced binding was observed only in chondroitin sulfate gels, and not in hyaluronic acid control gels. This enhanced binding activity resulted in enhanced dorsal root ganglion neurite outgrowth in chondroitin sulfate gels. Finally, the growth of regenerating dorsal root ganglia in these gels was imaged using label-free coherent anti-Stokes scattering microscopy. This technique generated detailed, high-quality images of live dorsal root ganglion neurites, which were comparable to fixed, F-actin-stained samples. Taken together, these results demonstrate the viability of this chondroitin sulfate hydrogel to serve as an effective implantable scaffold to aid in nerve root regeneration.

  20. Seasonal latitudinal and secular variations in temperature trend - evidence for influence of anthropogenic sulfate

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, D E; Schwartz, S E; Wagener, R; Benkovitz, C M [University of California at San Diego, La Jolla, CA (United States). Scripps Institute of Oceanography

    1993-11-19

    Tropospheric aerosols increase the shortwave reflectivity of the Earth-atmosphere system both by scattering light directly, in the absence of clouds, and by enhancing cloud reflectivity. The radiative forcing of climate exerted by anthropogenic sulfate aerosols, derived mainly from SO[sub 2] emitted from fossil fuel combustion, is opposite that due to anthropogenic greenhouse gases and is estimated to be of comparable average magnitude in Northern Hemisphere midlatitudes. However, persuasive evidence of climate response to this forcing has thus far been lacking. Here we examine patterns of seasonal and latitudinal variations in temperature anomaly trend for evidence of such a response. Pronounced minima in the rate of temperature increase in summer months in Northern Hemisphere midlatitudes are consistent with the latitudinal distribution of anthropogenic sulfate and changes in the rate of SO[sub 2] emissions over the industrial era.

  1. Oxygen isotopic fractionation during bacterial sulfate reduction

    Science.gov (United States)

    Balci, N.; Turchyn, A. V.; Lyons, T.; Bruchert, V.; Schrag, D. P.; Wall, J.

    2006-12-01

    Sulfur isotope fractionation during bacterial sulfate reduction (BSR) is understood to depend on a variety of environmental parameters, such as sulfate concentration, temperature, cell specific sulfate reduction rates, and the carbon substrate. What controls oxygen isotope fractionation during BSR is less well understood. Some studies have suggested that carbon substrate is important, whereas others concluded that there is a stoichiometric relationship between the fractionations of sulfur and oxygen during BSR. Studies of oxygen fractionation are complicated by isotopic equilibration between sulfur intermediates, particularly sulfite, and water. This process can modify the isotopic composition of the extracellular sulfate pool (δ18OSO4 ). Given this, the challenge is to distinguish between this isotopic equilibration and fractionations linked to the kinetic effects of the intercellular enzymes and the incorporation of sulfate into the bacterial cell. The δ18OSO4 , in concert with the sulfur isotope composition of sulfate (δ34SSO4), could be a powerful tool for understanding the pathways and environmental controls of BSR in natural systems. We will present δ18OSO4 data measured from batch culture growth of 14 different species of sulfate reducing bacteria for which sulfur isotope data were previously published. A general observation is that δ18OSO4 shows little isotopic change (kinetic effect during BSR and/or equilibration between sulfur intermediates and the isotopically light water (~-5‰) of the growth medium. Our present batch culture data do not allow us to convincingly isolate the magnitude and the controlling parameters of the kinetic isotope effect for oxygen. However, ongoing growth of mutant bacteria missing enzymes critical in the different steps of BSR may assist in this mission.

  2. Prevention of cognitive impairment in diabetic rats with oral magnesium sulfate

    Directory of Open Access Journals (Sweden)

    Gharibzadeh Sh

    2007-11-01

    Full Text Available Background: Diabetes mellitus is a common metabolic disorder accompanied with structural and functional changes in central and peripheral nervous system. Researches showed, memory disturbance were occurred in the course of diabetes. On the other hand, magnesium deficit has been described in diabetic patients. Some researches were showed that, appropriate magnesium supplementation can play a positive role in diabetic control.Methods: Locally produced male rats were used. Diabetes was induced with intravenous injection of 40 mg/kg streptozotosin. In treatment groups, the animals were received magnesium sulfate via drinking water (10 g/l. Eight weeks after diabetes confirmation, the animals were assessed on Morris Water Maze.Results: A significant decrease in time of platform finding (latency and distance of swimming in all four experimental days were seen in all groups. Mean latency in diabetic group was significantly higher than the other. This weak response was almost completely prevented by magnesium sulfate administration.Conclusion: It seems that after eight weeks magnesium sulfate administration (10g/l, spatial memory of the animals was improved in comparison to diabetic group that can suggest role of magnesium in recovery of diabetic animal memory.

  3. Bone sialoprotein II synthesized by cultured osteoblasts contains tyrosine sulfate

    International Nuclear Information System (INIS)

    Ecarot-Charrier, B.; Bouchard, F.; Delloye, C.

    1989-01-01

    Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with [35S] sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I

  4. Biotin starvation causes mitochondrial protein hyperacetylation and partial rescue by the SIRT3-like deacetylase Hst4p

    Science.gov (United States)

    Madsen, Christian T.; Sylvestersen, Kathrine B.; Young, Clifford; Larsen, Sara C.; Poulsen, Jon W.; Andersen, Marianne A.; Palmqvist, Eva A.; Hey-Mogensen, Martin; Jensen, Per B.; Treebak, Jonas T.; Lisby, Michael; Nielsen, Michael L.

    2015-01-01

    The essential vitamin biotin is a covalent and tenaciously attached prosthetic group in several carboxylases that play important roles in the regulation of energy metabolism. Here we describe increased acetyl-CoA levels and mitochondrial hyperacetylation as downstream metabolic effects of biotin deficiency. Upregulated mitochondrial acetylation sites correlate with the cellular deficiency of the Hst4p deacetylase, and a biotin-starvation-induced accumulation of Hst4p in mitochondria supports a role for Hst4p in lowering mitochondrial acetylation. We show that biotin starvation and knockout of Hst4p cause alterations in cellular respiration and an increase in reactive oxygen species (ROS). These results suggest that Hst4p plays a pivotal role in biotin metabolism and cellular energy homeostasis, and supports that Hst4p is a functional yeast homologue of the sirtuin deacetylase SIRT3. With biotin deficiency being involved in various metabolic disorders, this study provides valuable insight into the metabolic effects biotin exerts on eukaryotic cells. PMID:26158509

  5. Pectin of Prunus domestica L. alters sulfated structure of cell-surface heparan sulfate in differentiated Caco-2 cells through stimulation of heparan sulfate 6-O-endosulfatase-2.

    Science.gov (United States)

    Nishida, Mitsutaka; Murata, Kazuma; Kanamaru, Yoshihiro; Yabe, Tomio

    2014-01-01

    Although previous reports have suggested that pectin induces morphological changes of the small intestine in vivo, the molecular mechanisms have not been elucidated. As heparan sulfate plays important roles in development of the small intestine, to verify the involvement of heparan sulfate (HS) in the pectin-induced morphological changes of the small intestine, the effects of pectin from Prunus domestica L. on cell-surface HS were investigated using differentiated Caco-2 cells. Disaccharide compositional analysis revealed that sulfated structures of HS were markedly changed by pectin administration. Real-time RT-PCR showed that pectin upregulated human HS 6-O-endosulfatase-2 (HSulf-2) expression and markedly inhibited HSulf-1 expression. Furthermore, inhibition analysis suggested that pretreatment with fibronectin III1C fragment, RGD peptide, and ERK1/2 inhibitor suppressed pectin-induced HSulf-2 expression. These observations indicate that pectin induced the expression of HSulf-2 through the interaction with fibronectin, α5β1 integrin, and ERK1/2, thereby regulating the sulfated structure of HS on differentiated Caco-2 cells.

  6. Starvation of children in Syria--sanctions and the politics of revenge.

    Science.gov (United States)

    Sen, Kasturi

    2014-01-01

    As Syria completes two years of western sanctions (2011-13), their dramatic effects on health are being highlighted with first reports of starvation deaths among children in the suburbs of Damascus. Although heavy fighting has taken place in this area, experts had predicted for some time the unworkability of sanctions for regime change, arguing that only civilians would pay the price in a country (Syria in this case) which was once well on the way to meeting the Millennium Development Goals 4 targets on reducing child mortality. In this, as in the case of other "sanctioned" countries, it is not just "civilians" but the most vulnerable among them--children, who are experiencing the tragic consequences of sanctions.

  7. Heparan Sulfate and Chondroitin Sulfate Glycosaminoglycans Are Targeted by Bleomycin in Cancer Cells.

    Science.gov (United States)

    Li, Xiulian; Lan, Ying; He, Yanli; Liu, Yong; Luo, Heng; Yu, Haibo; Song, Ni; Ren, Sumei; Liu, Tianwei; Hao, Cui; Guo, Yunliang; Zhang, Lijuan

    2017-01-01

    Bleomycin is a clinically used anti-cancer drug that produces DNA breaks once inside of cells. However, bleomycin is a positively charged molecule and cannot get inside of cells by free diffusion. We previously reported that the cell surface negatively charged glycosaminoglycans (GAGs) may be involved in the cellular uptake of bleomycin. We also observed that a class of positively charged small molecules has Golgi localization once inside of the cells. We therefore hypothesized that bleomycin might perturb Golgi-operated GAG biosynthesis. We used stable isotope labeling coupled with LC/MS analysis of GAG disaccharides simultaneously from bleomycin-treated and non-treated cancer cells. To further understand the cytotoxicity of bleomycin and its relationship to GAGs, we used sodium chlorate to inhibit GAG sulfation and commercially available GAGs to compete for cell surface GAG/bleomycin interactions in seven cell lines including CHO745 defective in both heparan sulfate and chondroitin sulfate biosynthesis. we discovered that heparan sulfate GAG was significantly undersulfated and the quantity and disaccharide compositions of GAGs were changed in bleomycin-treated cells in a concentration- and time-dependent manner. We revealed that bleomycin-induced cytotoxicity was directly related to cell surface GAGs. GAGs were targeted by bleomycin both at cell surface and at Golgi. Thus, GAGs might be the biological relevant molecules that might be related to the bleomycin-induced fibrosis in certain cancer patients, a severe side effect with largely unknown molecular mechanism. © 2017 The Author(s). Published by S. Karger AG, Basel.

  8. The impact of temperature change on the activity and community composition of sulfate-reducing bacteria in arctic versus temperate marine sediments

    DEFF Research Database (Denmark)

    Robador, Alberto; Brüchert, Volker; Jørgensen, Bo Barker

    2009-01-01

    Arctic regions may be particularly sensitive to climate warming and, consequently, rates of carbon mineralization in warming marine sediment may also be affected. Using long-term (24 months) incubation experiments at 0°C, 10°C and 20°C, the temperature response of metabolic activity and community...... composition of sulfate-reducing bacteria were studied in the permanently cold sediment of north-western Svalbard (Arctic Ocean) and compared with a temperate habitat with seasonally varying temperature (German Bight, North Sea). Short-term 35S-sulfate tracer incubations in a temperature-gradient block...... (between -3.5°C and +40°C) were used to assess variations in sulfate reduction rates during the course of the experiment. Warming of arctic sediment resulted in a gradual increase of the temperature optima (Topt) for sulfate reduction suggesting a positive selection of psychrotolerant/mesophilic sulfate...

  9. Ferric sulfates on Mars: Surface Explorations and Laboratory Experiments

    Science.gov (United States)

    Wang, A.; Ling, Z.; Freeman, J. J.

    2008-12-01

    Recent results from missions to Mars have reinforced the importance of sulfates for Mars science. They are the hosts of water, the sinks of acidity, and maybe the most active species in the past and current surface/near-surface processes on Mars. Fe-sulfate was found frequently by Spirit and Opportunity rovers: jarosite in Meridiani Planum outcrops and a less specific "ferric sulfate" in the salty soils excavated by Spirit at Gusev Crater. Pancam spectral analysis suggests a variety of ferric sulfates in these soils, i.e. ferricopiapite, jarosite, fibroferrite, and rhomboclase. A change in the Pancam spectral features occurred in Tyrone soils after ~ 190 sols of exposure to surface conditions. Dehydration of ferric sulfate is a possible cause. We synthesized eight ferric sulfates and conducted a series of hydration/dehydration experiments. Our goal was to establish the stability fields and phase transition pathways of these ferric sulfates. In our experiments, water activity, temperature, and starting structure are the variables. No redox state change was observed. Acidic, neutral, and basic salts were used. Ferric sulfate sample containers were placed into relative humidity buffer solutions that maintain static relative humidity levels at three temperatures. The five starting phases were ferricopiapite (Fe4.67(SO4)6(OH)2.20H2O), kornelite (Fe2(SO4)3.7H2O), rhomboclase (FeH(SO4)2.4H2O), pentahydrite (Fe2(SO4)3.5H2O), and an amorphous phase (Fe2(SO4)3.5H2O). A total of one hundred fifty experiments have been running for nearly ten months. Thousands of coupled Raman and gravimetric measurements were made at intermediate steps to monitor the phase transitions. The first order discovery from these experiments is the extremely large stability field of ferricopiapite. Ferricopiapite is the major ferric sulfate to precipitate from a Fe3+-S-rich aqueous solution at mid-low temperature, and it has the highest H2O/Fe ratio (~ 4.3). However, unlike the Mg-sulfate with highest

  10. Ferrous Sulfate (Iron)

    Science.gov (United States)

    ... are allergic to ferrous sulfate, any other medications tartrazine (a yellow dye in some processed foods and ... in, tightly closed, and out of reach of children. Store it at room temperature and away from ...

  11. DEPENDENCY OF SULFATE SOLUBILITY ON MELT COMPOSITION AND MELT POLYMERIZATION

    International Nuclear Information System (INIS)

    JANTZEN, CAROL M.

    2004-01-01

    Sulfate and sulfate salts are not very soluble in borosilicate waste glass. When sulfate is present in excess it can form water soluble secondary phases and/or a molten salt layer (gall) on the melt pool surface which is purported to cause steam explosions in slurry fed melters. Therefore, sulfate can impact glass durability while formation of a molten salt layer on the melt pool can impact processing. Sulfate solubility has been shown to be compositionally dependent in various studies, (e.g. , B2O3, Li2O, CaO, MgO, Na2O, and Fe2O3 were shown to increase sulfate solubility while Al2O3 and SiO2 decreased sulfate solubility). This compositional dependency is shown to be related to the calculated melt viscosity at various temperatures and hence the melt polymerization

  12. Sulfated glycosaminoglycans in human vocal fold lamina propria

    Directory of Open Access Journals (Sweden)

    Sung Woo Park

    Full Text Available Abstract Introduction: The distribution, concentration and function of glycosaminoglycans in the various vocal fold tissues are still unclear. Objective: To evaluate the distribution and concentration of sulfated glycosaminoglycans in different layers of the human vocal fold according to gender and age. Methods: We used 11 vocal folds obtained from cadavers (7 men and 4 women with no laryngeal lesion, less than 12 h after death, and aged between 35 and 98 years. The folds underwent glycosaminoglycans extraction from the cover and ligament, and post-electrophoresis analysis. Data were compared according to the layer, age and gender. Results: The concentration of dermatan sulfate was significantly higher in all layers. No differences were observed in the total concentrations of glycosaminoglycans in layers studied according to gender. It is significantly lower in the cover of individuals aged below 60 years. Conclusion: Dermatan sulfate, chondroitin sulfate, and heparan sulfate were observed in the human vocal folds cover and ligament of both genders, with the concentration of dermatan sulfate being significantly higher in all layers. Glycosaminoglycans concentration on the cover is significantly lower in individuals below 60 years compared with elderly.

  13. Triatoma rubrovaria (Blanchard, 1843 (Hemiptera-Reduviidae-Triatominae III: patterns of feeding, defecation and resistance to starvation

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Almeida

    2003-04-01

    Full Text Available Data from the Chagas Disease Control Program indicate a growing domiciliary and peridomiciliary invasion of Triatoma rubrovaria in the State of Rio Grande do Sul, where it has become the most frequent triatomine species captured there since the control of T. infestans. Bionomic characteristics that could influence the vectorial capacity of T. rubrovaria as vector of Trypanosoma cruzi were evaluated: patterns of (i feeding, (ii defecation, and (iii resistance to starvation, using insects fed on mice. Fifty three percent of the females showed a defecation pattern conducive to chagasic transmission, defecating either on or near the bite site. The averages of the resistance to starvation varied from 48.1 to 179 days, for the first and fifth nymphal stages, respectively. Our study shows that with respect to the patterns of feeding, defecation and resistance to fasting, T. rubrovaria presented similar rates to the ones observed for other effective vector species, such as T. infestans. Thus, based on our studies we conclude that T. rubrovaria has biological characteristics that can positively influence its capacity to become infected and transmit T. cruzi, and also to keep residual populations after chemical control interventions.

  14. Tetrathionate and Elemental Sulfur Shape the Isotope Composition of Sulfate in Acid Mine Drainage

    Directory of Open Access Journals (Sweden)

    Nurgul Balci

    2017-08-01

    , acid production, and mixed valence state sulfur species generated by the oxidation of the two different substrates suggests a metabolic flexibility in response to sulfur substrate availability. Our results demonstrate that microbial processing of mixed-valence-state sulfur species generates a significant sulfur isotope fractionation in acidic environments and oxidation of mixed-valence state sulfur species may produce sulfate with characteristic sulfur and oxygen isotope signatures. Elemental sulfur and tetrathionate are not only intermediate-valence state sulfur compounds that play a central role in sulfur oxidation pathways, but also key factors in shaping these isotope patterns.

  15. DHEA-sulfate test

    Science.gov (United States)

    ... DHEA sulfate may be due to: Adrenal gland disorders that produce lower than normal amounts of adrenal hormones, including adrenal insufficiency and Addison disease The pituitary gland not producing normal amounts of its hormones ( hypopituitarism ) ...

  16. How sulfate-rich mine drainage affected aquatic ecosystem degradation in northeastern China, and potential ecological risk.

    Science.gov (United States)

    Zhao, Qian; Guo, Fen; Zhang, Yuan; Ma, Shuqin; Jia, Xiaobo; Meng, Wei

    2017-12-31

    Mining activity is an increasingly important stressor for freshwater ecosystems. However, the mechanism on how sulfate-rich mine drainage affects freshwater ecosystems is largely unknown, and its potential ecological risk has not been assessed so far. During 2009-2016, water and macroinvertebrate samples from 405 sample sites were collected along the mine drainage gradient from circum-neutral to alkaline waters in Hun-Tai River, Northeastern China. Results of linear regressions showed that sulfate-rich mine drainage was significantly positively correlated with the constituents typically derived from rock weathering (Ca 2+ , Mg 2+ and HCO 3 - +CO 3 2- ); the diversity of intolerant stream macroinvertebrates exhibited a steep decline along the gradient of sulfate-rich mine drainage. Meanwhile, stressor-response relationships between sulfate-rich mine drainage and macroinvertebrate communities were explored by two complementary statistical approaches in tandem (Threshold Indicator Taxa Analysis and the field-based method developed by USEPA). Results revealed that once stream sulfate concentrations in mine drainage exceeded 35mg/L, significant decline in the abundance of intolerant macroinvertebrate taxa occurred. An assessment of ecological risk posed by sulfate-rich mine drainage was conducted based on a tiered approach consisting of simple deterministic method (Hazard Quotient, HQ) to probabilistic method (Joint Probability Curve, JPC). Results indicated that sulfate-rich mine drainage posed a potential risk, and 64.62-84.88% of surface waters in Hun-Tai River exist serious risk while 5% threshold (HC 05 ) and 1% threshold (HC 01 ) were set up to protect macroinvertebrates, respectively. This study provided us a better understanding on the impacts of sulfate-rich mine drainage on freshwater ecosystems, and it would be helpful for future catchment management to protect streams from mining activity. Copyright © 2017. Published by Elsevier B.V.

  17. Evaluation of plant species for use in the control of acid sulfated soils in Paipa, Boyacá

    Directory of Open Access Journals (Sweden)

    Andrea Angélica Bernal Figueroa

    2014-07-01

    Full Text Available Acid sulfated soils are characterized by high amounts of iron and sulfur, which in presence of air are oxidized and form sulfuric horizons extremely acidic, generating environmental changes ranging from water pollution to problems associated with fertility and crop production, among others. This research was conducted in order to identify suitable plant species to control the acidity of these soils in the town of Paipa, Boyacá, Colombia. A completely randomized experimental design with 6 treatments and 3 replications was implemented in potting shed; there, the response of Beta vulgaris L. (forage beet, Brassica rapa L. (forage turnip and Raphanus sativus L. (forage radish on the acidity of sulfated acid soil, contrasted with a non-sulfated soil, was evaluated, after correction with liming. To assess the effects, pH and exchangeable acidity (H+ + Al+3 cmolc/kg were measured in the two types of soil before and after seeding ; the agronomic response of plants in each treatment was determined at the end of the growing season (120 days after seeding . On acid sulfated soils, species B. rapa, R. sativus and B. vulgaris along with the complementary use of liming as corrective induced a reduction in exchangeable acidity; B. rapa and R. sativus showed better growth potential and resistance, while B. vulgaris was affected in height and root diameter.

  18. Selenium inhibits sulfate-mediated methylmercury production in rice paddy soil.

    Science.gov (United States)

    Wang, Yong-Jie; Dang, Fei; Zhao, Jia-Ting; Zhong, Huan

    2016-06-01

    There is increasing interest in understanding factors controlling methylmercury (MeHg) production in mercury-contaminated rice paddy soil. Sulfate has been reported to affect MeHg biogeochemistry under anoxic conditions, and recent studies revealed that selenium (Se) could evidently reduce MeHg production in paddy soil. However, the controls of sulfate and Se on net MeHg production in paddy soil under fluctuating redox conditions remain largely unknown. Microcosm experiments were conducted to explore the effects of sulfate and Se on net MeHg production in rice paddy soil. Soil was added with 0-960 mg/kg sulfate, in the presence or absence of 3.0 mg/kg selenium (selenite or selenate), and incubated under anoxic (40 days) or suboxic conditions (5 days), simulating fluctuating redox conditions in rice paddy field. Sulfate addition moderately affected soil MeHg concentrations under anoxic conditions, while reoxidation resulted in evidently higher (18-40%) MeHg levels in sulfate amended soils than the control. The observed changes in net MeHg production were related to dynamics of sulfate and iron. However, Se could inhibit sulfate-mediated MeHg production in the soils: Se addition largely reduced net MeHg production in the soils (23-86%, compared to the control), despite of sulfate addition. Similarly, results of the pot experiments (i.e., rice cultivation in amended soils) indicated that soil MeHg levels were rather comparable in Se-amended soils during rice growth period, irrespective of added sulfate doses. The more important role of Se than sulfate in controlling MeHg production was explained by the formation of HgSe nanoparticles irrespective of the presence of sulfate, confirmed by TEM-EDX and XANES analysis. Our findings regarding the effects of sulfate and Se on net MeHg production in rice paddy soil together with the mechanistic explanation of the processes advance our understanding of MeHg dynamics and risk in soil-rice systems. Copyright © 2016 Elsevier

  19. Performance evaluation and microbial community analysis of the function and fate of ammonia in a sulfate-reducing EGSB reactor.

    Science.gov (United States)

    Wang, Depeng; Liu, Bo; Ding, Xinchun; Sun, Xinbo; Liang, Zi; Sheng, Shixiong; Du, Lingfeng

    2017-10-01

    Ammonia is widely distributed in sulfate-reducing bioreactor dealing with sulfate wastewater, which shows potential effect on the metabolic pathway of sulfate and ammonia. This study investigates the sulfate-reducing efficiency and microbial community composition in the sulfate-reducing EGSB reactor with the increasing ammonia loading. Results indicated that, compared with low ammonia loading (166-666 mg/L), the sulfate and organic matter removal efficiencies were improved gradually with the appropriate ammonia loading (1000-2000 mg/L), which increased from 63.58 ± 3.81 to 71.08 ± 1.36% and from 66.24 ± 1.32 to 81.88 ± 1.83%, respectively. Meanwhile, with the appropriate ratio of ammonia and sulfate (1.5-3.0) and hydraulic retention time (21 h), the sulfate-reducing anaerobic ammonia oxidation (SRAO) process was occurred efficiently, inducing the accumulation of S 0 (270 mg/L) and the simultaneous ammonia removal (70.83%) in EGSB reactor. Moreover, the key sulfate-reducing bacteria (SRB) (Desulfovibrio) and denitrification bacteria (Pseudomonas and Alcaligenes) were responsible for the sulfate and nitrogen removal in these phases, which accounted for 3.66-5.54 and 3.85-9.13%, respectively. However, as the ammonia loading higher than 3000 mg/L (phases 9 and 10), the sulfate-reducing efficiency was decreased to only 28.3 ± 1.26% with the ammonia removal rate of 18.4 ± 3.37% in the EGSB reactor. Meanwhile, the predominant SRB in phases 9 and 10 were Desulfomicrobium (1.22-1.99%) and Desulfocurvus (4.0-5.46%), and the denitrification bacteria accounted for only 0.88% (phase 10), indicating the low nitrogen removal rate.

  20. Growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus Selenka during periods of inactivity

    Science.gov (United States)

    Du, Rongbin; Zang, Yuanqi; Tian, Xiangli; Dong, Shuanglin

    2013-03-01

    The growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus, were investigated during periods of inactivity. The body weight, oxygen consumption rate (OCR), activities of acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD), and content of heat shock protein 70 (Hsp70) in the body wall and coelomic fluid of A. japonicus were measured during starvation, experimental aestivation and aestivation. The results showed that the body weight of sea cucumber in the three treatments decreased significantly during the experimental period ( P sea cucumber reduced in starvation and experimental aestivation treatments, but increased gradually in natural aestivation treatment. The activities of ACP and AKP of sea cucumber decreased gradually in all treatments, whereas those of SOD and CAT as well as Hsp70 content decreased in the starvation and experimental aestivation treatments and increased in natural aestivation treatment. The sea cucumber entered a state of aestivation at 24°C. To some extent, the animals in experimental aestivation were different from those in natural aestivation in metabolism and physiological response. These findings suggested that the aestivation mechanism of A. japonicus is complex and may not be attributed to the elevated temperature only.