Purine biosynthesis de novo by lymphocytes in gout

International Nuclear Information System (INIS)

Kamoun, P.; Chanard, J.; Brami, M.; Funck-Brentano, J.L.

1978-01-01

A method of measurement in vitro of purine biosynthesis de novo in human circulating blood lymphocytes is proposed. The rate of early reactions of purine biosynthesis de novo was determined by the incorporation of [ 14 C]formate into N-formyl glycinamide ribonucleotide when the subsequent reactions of the metabolic pathway were completely inhibited by the antibiotic azaserine. Synthesis of 14 C-labelled N-formyl glycinamide ribonucleotide by lymphocytes was measured in healthy control subjects and patients with primary gout or hyperuricaemia secondary to renal failure, with or without allopurinol therapy. The average synthesis was higher in gouty patients without therapy than in control subjects, but the values contained overlap the normal range. In secondary hyperuricaemia the synthesis was at same value as in control subjects. These results are in agreement with the inconstant acceleration of purine biosynthesis de novo in gouty patients as seen by others with measurement of [ 14 C]glycine incorporation into urinary uric acid. (author)

Removal of oxygen free-radical-induced 5′,8-purine cyclodeoxynucleosides from DNA by the nucleotide excision-repair pathway in human cells

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Kuraoka, Isao; Bender, Christina; Romieu, Anthony; Cadet, Jean; Wood, Richard D.; Lindahl, Tomas

2000-01-01

Exposure of cellular DNA to reactive oxygen species generates several classes of base lesions, many of which are removed by the base excision-repair pathway. However, the lesions include purine cyclodeoxynucleoside formation by intramolecular crosslinking between the C-8 position of adenine or guanine and the 5′ position of 2-deoxyribose. This distorting form of DNA damage, in which the purine is attached by two covalent bonds to the sugar-phosphate backbone, occurs as distinct diastereoisomers. It was observed here that both diastereoisomers block primer extension by mammalian and microbial replicative DNA polymerases, using DNA with a site-specific purine cyclodeoxynucleoside residue as template, and consequently appear to be cytotoxic lesions. Plasmid DNA containing either the 5′R or 5′S form of 5′,8-cyclo-2-deoxyadenosine was a substrate for the human nucleotide excision-repair enzyme complex. The R diastereoisomer was more efficiently repaired than the S isomer. No correction of the lesion by direct damage reversal or base excision repair was detected. Dual incision around the lesion depended on the core nucleotide excision-repair protein XPA. In contrast to several other types of oxidative DNA damage, purine cyclodeoxynucleosides are chemically stable and would be expected to accumulate at a slow rate over many years in the DNA of nonregenerating cells from xeroderma pigmentosum patients. High levels of this form of DNA damage might explain the progressive neurodegeneration seen in XPA individuals. PMID:10759556

The Stringent Response Induced by Phosphate Limitation Promotes Purine Salvage in Agrobacterium fabrum.

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Sivapragasam, Smitha; Deochand, Dinesh K; Meariman, Jacob K; Grove, Anne

2017-10-31

Agrobacterium fabrum induces tumor growth in susceptible plant species. The upregulation of virulence genes that occurs when the bacterium senses plant-derived compounds is enhanced by acidic pH and limiting inorganic phosphate. Nutrient starvation may also trigger the stringent response, and purine salvage is among the pathways expected to be favored under such conditions. We show here that phosphate limitation induces the stringent response, as evidenced by production of (p)ppGpp, and that the xdhCSML operon encoding the purine salvage enzyme xanthine dehydrogenase is upregulated ∼15-fold. The xdhCSML operon is under control of the TetR family transcription factor XdhR; direct binding of ppGpp to XdhR attenuates DNA binding, and the enhanced xdhCSML expression correlates with increased cellular levels of (p)ppGpp. Xanthine dehydrogenase may also divert purines away from salvage pathways to form urate, the ligand for the transcription factor PecS, which in the plant pathogen Dickeya dadantii is a key regulator of virulence gene expression. However, urate levels remain low under conditions that produce increased levels of xdhCSML expression, and neither acidic pH nor limiting phosphate results in induction of genes under control of PecS. Instead, expression of such genes is induced only by externally supplemented urate. Taken together, our data indicate that purine salvage is favored during the stringent response induced by phosphate starvation, suggesting that control of this pathway may constitute a novel approach to modulating virulence. Because bacterial purine catabolism appears to be unaffected, as evidenced by the absence of urate accumulation, we further propose that the PecS regulon is induced by only host-derived urate.

Purine salvage in the apicomplexan Sarcocystis neurona, and generation of hypoxanthine-xanthine-guanine phosphoribosyltransferase-deficient clones for positive-negative selection of transgenic parasites.

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Dangoudoubiyam, Sriveny; Zhang, Zijing; Howe, Daniel K

2014-09-01

Sarcocystis neurona is an apicomplexan parasite that causes severe neurological disease in horses and marine mammals. The Apicomplexa are all obligate intracellular parasites that lack purine biosynthesis pathways and rely on the host cell for their purine requirements. Hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK) are key enzymes that function in two complementary purine salvage pathways in apicomplexans. Bioinformatic searches of the S. neurona genome revealed genes encoding HXGPRT, AK and all of the major purine salvage enzymes except purine nucleoside phosphorylase. Wild-type S. neurona were able to grow in the presence of mycophenolic acid (MPA) but were inhibited by 6-thioxanthine (6-TX), suggesting that the pathways involving either HXGPRT or AK are functional in this parasite. Prior work with Toxoplasma gondii demonstrated the utility of HXGPRT as a positive-negative selection marker. To enable the use of HXGPRT in S. neurona, the SnHXGPRT gene sequence was determined and a gene-targeting plasmid was transfected into S. neurona. SnHXGPRT-deficient mutants were selected with 6-TX, and single-cell clones were obtained. These Sn∆HXG parasites were susceptible to MPA and could be complemented using the heterologous T. gondii HXGPRT gene. In summary, S. neurona possesses both purine salvage pathways described in apicomplexans, thus allowing the use of HXGPRT as a positive-negative drug selection marker in this parasite.

Potassium recycling pathways in the human cochlea.

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Weber, P C; Cunningham, C D; Schulte, B A

2001-07-01

Potential pathways for recycling potassium (K+) used in the maintenance of inner ear electrochemical gradients have been elucidated in animal models. However, little is known about K+ transport in the human cochlea. This study was designed to characterize putative K+ recycling pathways in the human ear and to determine whether observations from animal models can be extrapolated to humans. A prospective laboratory study using an immunohistochemical approach to analyze the distribution of key ion transport mediators in the human cochlea. Human temporal bones were fixed in situ within 1 to 6 hours of death and subsequently harvested at autopsy. Decalcification was accomplished with the aid of microwaving. Immunohistochemical staining was then performed to define the presence and cell type-specific distribution of Na,K-ATPase, sodium-potassium-chloride cotransporter (NKCC), and carbonic anhydrase (CA) in the inner ear. Staining patterns visualized in the human cochlea closely paralleled those seen in other species. Anti-Na,K-ATPase stained strongly the basolateral plasma membrane of strial marginal cells and nerve endings underlying hair cells. This antibody also localized Na,K-ATPase to type II, type IV, and type V fibrocytes in the spiral ligament and in limbal fibrocytes. NKCC was present in the basolateral membrane of strial marginal cells as well as in type II, type V, and limbal fibrocytes. Immunoreactive carbonic anhydrase was present in type I and type III fibrocytes and in epithelial cells lining Reissner's membrane and the spiral prominence. The distribution of several major ion transport proteins in the human cochlea is similar but not identical to that described in various rodent models. These results support the presence of a complex system for recycling and regulating K+ homeostasis in the human cochlea, similar to that described in other mammalian species.

Purine content of some Philippine foods

International Nuclear Information System (INIS)

Lontoc, A.V.; Ladines, E.O.; Jalandoon, S.A.

1993-01-01

To facilitate dietary advice for prevention and management of hyperuricemia, the content of individual purines, namely: adenine, hypoxanthine, guanine and xanthine was determined in market samples of 161 legumes and dried beans, 41 organ meats, and 25 finfishes and shellfishes using Waters HPLC Model ALC/GPC 244. Analysis for moisture, protein and purines were conducted on the slurries or dried forms of the edible portions of the food samples. Food samples were subsequently classified into three categories adapted from Williams' dietary guide for purines, expressed in decreasing levels of total purines per 100 g serving. Category 1 foods are those that contain very large amount (150 to 1000 mg) of total purines; category 2 foods are those that contain a large amount (75-<150 mg) of total purines; and category 3 foods are those that contain a moderate amount (up to 75 mg) of total purines. (auth.). 17 refs.; 8 tabs

Recycling of epidermal growth factor-receptor complexes in A431 cells: Identification of dual pathways

International Nuclear Information System (INIS)

Sorkin, A.; Krolenko, S.; Kudrjavtceva, N.; Lazebnik, J.; Teslenko, L.; Soderquist, A.M.; Nikolsky, N.

1991-01-01

The intracellular sorting of EGF-receptor complexes (EGF-RC) has been studied in human epidermoid carcinoma A431 cells. Recycling of EGF was found to occur rapidly after internalization at 37 degrees C. The initial rate of EGF recycling was reduced at 18 degrees C. A significant pool of internalized EGF was incapable of recycling at 18 degrees C but began to recycle when cells were warmed to 37 degrees C. The relative rate of EGF outflow at 37 degrees C from cells exposed to an 18 degrees C temperature block was slower (t1/2 approximately 20 min) than the rate from cells not exposed to a temperature block (t1/2 approximately 5-7 min). These data suggest that there might be both short- and long-time cycles of EGF recycling in A431 cells. Examination of the intracellular EGF-RC dissociation and dynamics of short- and long-time recycling indicated that EGF recycled as EGF-RC. Moreover, EGF receptors that were covalently labeled with a photoactivatable derivative of 125 I-EGF recycled via the long-time pathway at a rate similar to that of 125 I-EGF. Since EGF-RC degradation was also blocked at 18 degrees C, we propose that sorting to the lysosomal and long-time recycling pathway may occur after a highly temperature-sensitive step, presumably in the late endosomes

Evolutionary convergence in the biosyntheses of the imidazole moieties of histidine and purines.

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Alberto Vázquez-Salazar

Full Text Available The imidazole group is an ubiquitous chemical motif present in several key types of biomolecules. It is a structural moiety of purines, and plays a central role in biological catalysis as part of the side-chain of histidine, the amino acid most frequently found in the catalytic site of enzymes. Histidine biosynthesis starts with both ATP and the pentose phosphoribosyl pyrophosphate (PRPP, which is also the precursor for the de novo synthesis of purines. These two anabolic pathways are also connected by the imidazole intermediate 5-aminoimidazole-4-carboxamide ribotide (AICAR, which is synthesized in both routes but used only in purine biosynthesis. Rather surprisingly, the imidazole moieties of histidine and purines are synthesized by different, non-homologous enzymes. As discussed here, this phenomenon can be understood as a case of functional molecular convergence.In this work, we analyze these polyphyletic processes and argue that the independent origin of the corresponding enzymes is best explained by the differences in the function of each of the molecules to which the imidazole moiety is attached. Since the imidazole present in histidine is a catalytic moiety, its chemical arrangement allows it to act as an acid or a base. On the contrary, the de novo biosynthesis of purines starts with an activated ribose and all the successive intermediates are ribotides, with the key β-glycosidic bondage joining the ribose and the imidazole moiety. This prevents purine ribonucleotides to exhibit any imidazole-dependent catalytic activity, and may have been the critical trait for the evolution of two separate imidazole-synthesizing-enzymes. We also suggest that, in evolutionary terms, the biosynthesis of purines predated that of histidine.As reviewed here, other biosynthetic routes for imidazole molecules are also found in extant metabolism, including the autocatalytic cyclization that occurs during the formation of creatinine from creatine phosphate

Gene set analysis of purine and pyrimidine antimetabolites cancer therapies.

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Fridley, Brooke L; Batzler, Anthony; Li, Liang; Li, Fang; Matimba, Alice; Jenkins, Gregory D; Ji, Yuan; Wang, Liewei; Weinshilboum, Richard M

2011-11-01

Responses to therapies, either with regard to toxicities or efficacy, are expected to involve complex relationships of gene products within the same molecular pathway or functional gene set. Therefore, pathways or gene sets, as opposed to single genes, may better reflect the true underlying biology and may be more appropriate units for analysis of pharmacogenomic studies. Application of such methods to pharmacogenomic studies may enable the detection of more subtle effects of multiple genes in the same pathway that may be missed by assessing each gene individually. A gene set analysis of 3821 gene sets is presented assessing the association between basal messenger RNA expression and drug cytotoxicity using ethnically defined human lymphoblastoid cell lines for two classes of drugs: pyrimidines [gemcitabine (dFdC) and arabinoside] and purines [6-thioguanine and 6-mercaptopurine]. The gene set nucleoside-diphosphatase activity was found to be significantly associated with both dFdC and arabinoside, whereas gene set γ-aminobutyric acid catabolic process was associated with dFdC and 6-thioguanine. These gene sets were significantly associated with the phenotype even after adjusting for multiple testing. In addition, five associated gene sets were found in common between the pyrimidines and two gene sets for the purines (3',5'-cyclic-AMP phosphodiesterase activity and γ-aminobutyric acid catabolic process) with a P value of less than 0.0001. Functional validation was attempted with four genes each in gene sets for thiopurine and pyrimidine antimetabolites. All four genes selected from the pyrimidine gene sets (PSME3, CANT1, ENTPD6, ADRM1) were validated, but only one (PDE4D) was validated for the thiopurine gene sets. In summary, results from the gene set analysis of pyrimidine and purine therapies, used often in the treatment of various cancers, provide novel insight into the relationship between genomic variation and drug response.

Two novel WD40 domain–containing proteins, Ere1 and Ere2, function in the retromer-mediated endosomal recycling pathway

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Shi, Yufeng; Stefan, Christopher J.; Rue, Sarah M.; Teis, David; Emr, Scott D.

2011-01-01

Regulated secretion, nutrient uptake, and responses to extracellular signals depend on cell-surface proteins that are internalized and recycled back to the plasma membrane. However, the underlying mechanisms that govern membrane protein recycling to the cell surface are not fully known. Using a chemical-genetic screen in yeast, we show that the arginine transporter Can1 is recycled back to the cell surface via two independent pathways mediated by the sorting nexins Snx4/41/42 and the retromer complex, respectively. In addition, we identify two novel WD40-domain endosomal recycling proteins, Ere1 and Ere2, that function in the retromer pathway. Ere1 is required for Can1 recycling via the retromer-mediated pathway, but it is not required for the transport of other retromer cargoes, such as Vps10 and Ftr1. Biochemical studies reveal that Ere1 physically interacts with internalized Can1. Ere2 is present in a complex containing Ere1 on endosomes and functions as a regulator of Ere1. Taken together, our results suggest that Snx4/41/42 and the retromer comprise two independent pathways for the recycling of internalized cell-surface proteins. Moreover, a complex containing the two novel proteins Ere1 and Ere2 mediates cargo-specific recognition by the retromer pathway. PMID:21880895

Structure, stability, and thermodynamics of a short intermolecular purine-purine-pyrimidine triple helix

International Nuclear Information System (INIS)

Pilch, D.S.; Shafer, R.H.; Levenson, C.

1991-01-01

The authors have investigated the structure and physical chemistry of the d(C 3 T 4 C 3 )·2[d(G 3 A 4 G 3 )] triple helix by polyacrylamide gel electrophoresis (PAGE), 1 H NMR, and ultraviolet (UV) absorption spectroscopy. The triplex was stabilized with MgCl 2 at neutral pH. PAGE studies verify the stoichiometry of the strands comprising the triplex and indicate that the orientation of the third strand in purine-purine-pyrimidine (pur-pur-pyr) triplexes is antiparallel with respect to the purine strand of the underlying duplex. Imino proton NMR spectra provide evidence for the existence of new purine-purine (pur·pur) hydrogen bonds, in addition to those of the Watson-Crick (W-C) base pairs, in the triplex structure. These new hydrogen bonds are likely to correspond to the interaction between third-strand guanine NH1 imino protons and the N7 atoms of guanine residues on the puring strand of the underlying duplex. Thermal denaturation of the triplex proceeds to single strands in one step, under the conditions used in this study. Binding of the third strand appears to enhance the thermal stability of the duplex by 1-3 C, depending on the DNA concentration. This marked enhancement in stability, coupled with the lack of an acidic pH requirement, suggests that pur-pur-pyr triplexes are appealing choices for use in applications involving oligonucleotide targeting of duplex DNA in vitro and in vivo

Bacillus subtilis guanine deaminase is encoded by the yknA gene and is induced during growth with purines as the nitrogen source

DEFF Research Database (Denmark)

Nygaard, P.; Bested, S. M.; Andersen, K. A. K.

2000-01-01

amino acid polypeptide and was preceded by a promoter sequence that is recognized by the A form of RNA polymerase. High levels of GDEase were found in cells grown with purines and intermediary compounds of the purine catabolic pathway as nitrogen sources. Allantoic acid, most likely, is a low molecular...

Involvement of the ribose operon repressor RbsR in regulation of purine nucleotide synthesis in Escherichia coli.

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Shimada, Tomohiro; Kori, Ayako; Ishihama, Akira

2013-07-01

Escherichia coli is able to utilize d-ribose as its sole carbon source. The genes for the transport and initial-step metabolism of d-ribose form a single rbsDACBK operon. RbsABC forms the ABC-type high-affinity d-ribose transporter, while RbsD and RbsK are involved in the conversion of d-ribose into d-ribose 5-phosphate. In the absence of inducer d-ribose, the ribose operon is repressed by a LacI-type transcription factor RbsR, which is encoded by a gene located downstream of this ribose operon. At present, the rbs operon is believed to be the only target of regulation by RbsR. After Genomic SELEX screening, however, we have identified that RbsR binds not only to the rbs promoter but also to the promoters of a set of genes involved in purine nucleotide metabolism. Northern blotting analysis indicated that RbsR represses the purHD operon for de novo synthesis of purine nucleotide but activates the add and udk genes involved in the salvage pathway of purine nucleotide synthesis. Taken together, we propose that RbsR is a global regulator for switch control between the de novo synthesis of purine nucleotides and its salvage pathway. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Informal E-waste recycling in developing countries: review of metal(loid)s pollution, environmental impacts and transport pathways.

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Ackah, Michael

2017-11-01

Crude or primitive recycling practices are often adopted in material resource recovery from E-waste in developing nations. Significant human health and environmental impacts may occur because of such practices. Literature on metal(loid)s pollution during E-waste processing is fragmented. Here, I review the health and environmental impacts of E-waste recycling operations and transport pathways of metal(loid)s, dispersed during operations. This paper is organised into five sections. Section 1 relates to the background of global E-waste generation and legal/illegal trade, citing specific cases from Ghana and other developing nations. Section 2 provides a brief information on sources of metal(loid)s in E-waste. Section 3 describes characteristics of informal E-waste recycling operations in developing nations. Section 4 examines the health and environmental impacts in E-waste recycling while section 5 evaluates major transport pathways of metal(loid)s contaminants.

Abiotic synthesis of purines and other heterocyclic compounds by the action of electrical discharges

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Yuasa, S.; Flory, D.; Basile, B.; Oro, J.

1984-01-01

The synthesis of purines and pyrimidines using Oparin-Urey-type primitive earth atmospheres has been demonstrated by reacting methane, ethane, and ammonia in electrical discharges. Adenine, guaine, 4-aminoimidazole-5-carboxamide (AICA), and isocytosine have been identified by UV spectrometry and paper chromatography as the products of the reaction. The total yields of the identified heterocyclic compounds are 0.0023 percent. It is concluded that adenine synthesis occurs at a much lower concentration of hydrogen cyanide than has been shown by earlier studies. Pathways for the synthesis of purines from hydrogen cyanide are discussed, and a comparison of the heterocyclic compounds that have been identified in meteorites and in prebiotic reactions is presented.

Simultaneous quantification by HPLC of purines in umami soup stock and evaluation of their effects on extracellular and intracellular purine metabolism.

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Fukuuchi, T; Iyama, N; Yamaoka, N; Kaneko, K

2018-04-13

Ribonucleotide flavor enhancers such as inosine monophosphate (IMP) and guanosine monophosphate (GMP) provide umami taste, similarly to glutamine. Japanese cuisine frequently uses soup stocks containing these nucleotides to enhance umami. We quantified 18 types of purines (nucleotides, nucleosides, and purine bases) in three soup stocks (chicken, consommé, and dried bonito soup). IMP was the most abundant purine in all umami soup stocks, followed by hypoxanthine, inosine, and GMP. The IMP content of dried bonito soup was the highest of the three soup stocks. We also evaluated the effects of these purines on extracellular and intracellular purine metabolism in HepG2 cells after adding each umami soup stock to the cells. An increase in inosine and hypoxanthine was evident 1 h and 4 h after soup stock addition, and a low amount of xanthine and guanosine was observed in the extracellular medium. The addition of chicken soup stock resulted in increased intracellular and extracellular levels of uric acid and guanosine. Purine metabolism may be affected by ingredients present in soups.

Alterations in tryptophan and purine metabolism in cocaine addiction: a metabolomic study.

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Patkar, Ashwin A; Rozen, Steve; Mannelli, Paolo; Matson, Wayne; Pae, Chi-Un; Krishnan, K Ranga; Kaddurah-Daouk, Rima

2009-10-01

Mapping metabolic "signatures" can provide new insights into addictive mechanisms and potentially identify biomarkers and therapeutic targets. We examined the differences in metabolites related to the tyrosine, tryptophan, purine, and oxidative stress pathways between cocaine-dependent subjects and healthy controls. Several of these metabolites serve as biological indices underlying the mechanisms of reinforcement, toxicity, and oxidative stress. Metabolomic analysis was performed in 18 DSM-IV-diagnosed cocaine-dependent individuals with at least 2 weeks of abstinence and ten drug-free controls. Plasma concentrations of 37 known metabolites were analyzed and compared using a liquid chromatography electrochemical array platform. Multivariate analyses were used to study the relationship between severity of drug use [Addiction Severity Index (ASI) scores] and biological measures. Cocaine subjects showed significantly higher levels of n-methylserotonin (p cocaine and control groups with no overlap. Alterations in the methylation processes in the serotonin pathways and purine metabolism seem to be associated with chronic exposure to cocaine. Given the preliminary nature and cross-sectional design of the study, the findings need to be confirmed in larger samples of cocaine-dependent subjects, preferably in a longitudinal design.

Recycling endosomes in human cytotoxic T lymphocytes constitute an auxiliary intracellular trafficking pathway for newly synthesized perforin

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Lesteberg, Kelsey E.; Orange, Jordan S.; Makedonas, George

2018-01-01

Background Although cytotoxic T lymphocytes (CTLs) store perforin within cytoplasmic secretory granules for immediate use, perforin is synthesized anew within hours of TCR stimulation. Previously, we observed new perforin protein at an immunologic synapse independent of secretory lysosomes; herein we aimed to determine how new perforin transits to the synapse if not via lytic granules. Results We analyzed antigen-specific human CTLs via imaging flow cytometry and high-resolution confocal microscopy, with attention to intracellular trafficking components and new perforin. The recycling endosome compartments identified by rab8, rab11a, rab4, and rab37 co-localized with new perforin, as well as the SNAREs vti1b and VAMP4. After ablating the function of the recycling endosome pathway, we observed a relative accumulation of new perforin in rab8 vesicles. Conclusions The recycling endosome pathway may serve as an auxiliary intracellular route for the delivery of new perforin to an immunologic synapse in order to perpetuate a cytotoxic response. PMID:28822075

Degradation of brown adipocyte purine nucleotides regulates uncoupling protein 1 activity

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Tobias Fromme

2018-02-01

Full Text Available Objective: Non-shivering thermogenesis in mammalian brown adipose tissue depends on thermogenic uncoupling protein 1. Its activity is triggered by free fatty acids while purine nucleotides mediate inhibition. During activation, it is thought that free fatty acids overcome purine-mediated inhibition. We measured the cellular concentration and the release of purine nucleotide metabolites to uncover a possible role of purine nucleotide degradation in uncoupling protein 1 activation. Methods: With mass spectrometry, purine nucleotide metabolites were quantified in cellular homogenates and supernatants of cultured primary brown adipocytes. We also determined oxygen consumption in response to a β-adrenergic agonist. Results: Upon adrenergic activation, brown adipocytes decreased the intracellular concentration of inhibitory nucleotides (ATP, ADP, GTP and GDP and released the respective degradation products. At the same time, an increase in cellular calcium occurred. None of these phenomena occurred in white adipocytes or myotubes. The brown adipocyte expression of enzymes implicated in purine metabolic remodeling is altered upon cold exposure. Pharmacological and genetic interference of purine metabolism altered uncoupling protein 1 mediated uncoupled respiration. Conclusion: Adrenergic stimulation of brown adipocytes lowers the intracellular concentration of purine nucleotides, thereby contributing to uncoupling protein 1 activation. Keywords: Purine nucleotides, Uncoupling protein 1, Brown adipose tissue, Non-shivering thermogenesis, HILIC-MS/MS, Guanosine monophosphate reductase

The purine-utilizing bacterium Clostridium acidurici 9a: a genome-guided metabolic reconsideration.

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Katrin Hartwich

Full Text Available Clostridium acidurici is an anaerobic, homoacetogenic bacterium, which is able to use purines such as uric acid as sole carbon, nitrogen, and energy source. Together with the two other known purinolytic clostridia C. cylindrosporum and C. purinilyticum, C. acidurici serves as a model organism for investigation of purine fermentation. Here, we present the first complete sequence and analysis of a genome derived from a purinolytic Clostridium. The genome of C. acidurici 9a consists of one chromosome (3,105,335 bp and one small circular plasmid (2,913 bp. The lack of candidate genes encoding glycine reductase indicates that C. acidurici 9a uses the energetically less favorable glycine-serine-pyruvate pathway for glycine degradation. In accordance with the specialized lifestyle and the corresponding narrow substrate spectrum of C. acidurici 9a, the number of genes involved in carbohydrate transport and metabolism is significantly lower than in other clostridia such as C. acetobutylicum, C. saccharolyticum, and C. beijerinckii. The only amino acid that can be degraded by C. acidurici is glycine but growth on glycine only occurs in the presence of a fermentable purine. Nevertheless, the addition of glycine resulted in increased transcription levels of genes encoding enzymes involved in the glycine-serine-pyruvate pathway such as serine hydroxymethyltransferase and acetate kinase, whereas the transcription levels of formate dehydrogenase-encoding genes decreased. Sugars could not be utilized by C. acidurici but the full genetic repertoire for glycolysis was detected. In addition, genes encoding enzymes that mediate resistance against several antimicrobials and metals were identified. High resistance of C. acidurici towards bacitracin, acriflavine and azaleucine was experimentally confirmed.

The purine-utilizing bacterium Clostridium acidurici 9a: a genome-guided metabolic reconsideration.

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Hartwich, Katrin; Poehlein, Anja; Daniel, Rolf

2012-01-01

Clostridium acidurici is an anaerobic, homoacetogenic bacterium, which is able to use purines such as uric acid as sole carbon, nitrogen, and energy source. Together with the two other known purinolytic clostridia C. cylindrosporum and C. purinilyticum, C. acidurici serves as a model organism for investigation of purine fermentation. Here, we present the first complete sequence and analysis of a genome derived from a purinolytic Clostridium. The genome of C. acidurici 9a consists of one chromosome (3,105,335 bp) and one small circular plasmid (2,913 bp). The lack of candidate genes encoding glycine reductase indicates that C. acidurici 9a uses the energetically less favorable glycine-serine-pyruvate pathway for glycine degradation. In accordance with the specialized lifestyle and the corresponding narrow substrate spectrum of C. acidurici 9a, the number of genes involved in carbohydrate transport and metabolism is significantly lower than in other clostridia such as C. acetobutylicum, C. saccharolyticum, and C. beijerinckii. The only amino acid that can be degraded by C. acidurici is glycine but growth on glycine only occurs in the presence of a fermentable purine. Nevertheless, the addition of glycine resulted in increased transcription levels of genes encoding enzymes involved in the glycine-serine-pyruvate pathway such as serine hydroxymethyltransferase and acetate kinase, whereas the transcription levels of formate dehydrogenase-encoding genes decreased. Sugars could not be utilized by C. acidurici but the full genetic repertoire for glycolysis was detected. In addition, genes encoding enzymes that mediate resistance against several antimicrobials and metals were identified. High resistance of C. acidurici towards bacitracin, acriflavine and azaleucine was experimentally confirmed.

Using purine skews to predict genes in AT-rich poxviruses

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Upton Chris

2005-02-01

Full Text Available Abstract Background Clusters or runs of purines on the mRNA synonymous strand have been found in many different organisms including orthopoxviruses. The purine bias that is exhibited by these clusters can be observed using a purine skew and in the case of poxviruses, these skews can be used to help determine the coding strand of a particular segment of the genome. Combined with previous findings that minor ORFs have lower than average aspartate and glutamate composition and higher than average serine composition, purine content can be used to predict the likelihood of a poxvirus ORF being a "real gene". Results Using purine skews and a "quality" measure designed to incorporate previous findings about minor ORFs, we have found that in our training case (vaccinia virus strain Copenhagen, 59 of 65 minor (small and unlikely to be a real genes ORFs were correctly classified as being minor. Of the 201 major (large and likely to be real genes vaccinia ORFs, 192 were correctly classified as being major. Performing a similar analysis with the entomopoxvirus amsacta moorei (AMEV, it was found that 4 major ORFs were incorrectly classified as minor and 9 minor ORFs were incorrectly classified as major. The purine abundance observed for major ORFs in vaccinia virus was found to stem primarily from the first codon position with both the second and third codon positions containing roughly equal amounts of purines and pyrimidines. Conclusion Purine skews and a "quality" measure can be used to predict functional ORFs and purine skews in particular can be used to determine which of two overlapping ORFs is most likely to be the real gene if neither of the two ORFs has orthologs in other poxviruses.

Catalase increases ethanol oxidation through the purine catabolism in rat liver.

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Villalobos-García, Daniel; Hernández-Muñoz, Rolando

2017-08-01

Hepatic ethanol oxidation increases according to its concentration and is raised to near-saturation levels of alcohol dehydrogenase (ADH); therefore, re-oxidation of NADH becomes rate limiting in ethanol metabolism by the liver. Adenosine is able to increase liver ethanol oxidation in both in vivo and in vitro conditions; the enhancement being related with the capacity of the nucleoside to accelerate the transport of cytoplasmic reducing equivalents to mitochondria, by modifying the subcellular distribution of the malate-aspartate shuttle components. In the present study, we explored the putative effects of adenosine and other purines on liver ethanol oxidation mediated by non-ADH pathways. Using the model of high precision-cut rat liver slices, a pronounced increase of ethanol oxidation was found in liver slices incubated with various intermediates of the purine degradation pathway, from adenosine to uric acid (175-230%, over controls). Of these, urate had the strongest (230%), whereas xanthine had the less pronounced effect (178% over controls). The enhancement was not abolished by 4-methylpyrazole, indicating that the effect was independent of alcohol dehydrogenase. Conversely, aminotriazole, a catalase inhibitor, completely abolished the effect, pointing out that this enhanced ethanol oxidation is mediated by catalase activity. It is concluded that the H 2 O 2 needed for catalase activity is derived from the oxidation of (hypo)xanthine by xanthine oxidase and the oxidation of urate by uricase. The present and previous data led us to propose that, depending on the metabolic conditions, adenosine might be able to stimulate the metabolism of ethanol through different pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

α-Taxilin interacts with sorting nexin 4 and participates in the recycling pathway of transferrin receptor.

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Hiroshi Sakane

Full Text Available Membrane traffic plays a crucial role in delivering proteins and lipids to their intracellular destinations. We previously identified α-taxilin as a binding partner of the syntaxin family, which is involved in intracellular vesicle traffic. α-Taxilin is overexpressed in tumor tissues and interacts with polymerized tubulin, but the precise function of α-taxilin remains unclear. Receptor proteins on the plasma membrane are internalized, delivered to early endosomes and then either sorted to the lysosome for degradation or recycled back to the plasma membrane. In this study, we found that knockdown of α-taxilin induced the lysosomal degradation of transferrin receptor (TfnR, a well-known receptor which is generally recycled back to the plasma membrane after internalization, and impeded the recycling of transferrin. α-Taxilin was immunoprecipitated with sorting nexin 4 (SNX4, which is involved in the recycling of TfnR. Furthermore, knockdown of α-taxilin decreased the number and length of SNX4-positive tubular structures. We report for the first time that α-taxilin interacts with SNX4 and plays a role in the recycling pathway of TfnR.

Glucagon infusion increases rate of purine synthesis de novo in rat liver

International Nuclear Information System (INIS)

Itakura, Mitsuo; Maeda, Noriaki; Tsuchiya, Masami; Yamashita, Kamejiro

1987-01-01

Based on the parallel increases of glucagon, the second peak of hepatic cAMP, and the rate of purine synthesis de novo in the prereplicative period in regenerating rate liver after a 70% hepatectomy, it was hypothesized that glucagon is responsible for the increased rate of purine synthesis de novo. To test this hypothesis, the effect of glucagon or dibutyryl cAMP infusion on the rate of purine synthesis de novo in rat liver was studied. Glucagon infusion but not insulin or glucose infusion increased the rate of purine synthesis de novo, which was assayed by [ 14 C]glycine or [ 14 C]formate incorporation, by 2.7- to 4.3-fold. Glucagon infusion increased cAMP concentrations by 4.9-fold and 5-phosphoribosyl-1-pyrophosphate concentrations by 1.5-fold in liver but did not change the specific activity of amidophosphoribosyltransferase or purine ribonucleotide concentrations. Dibutyryl cAMP infusion also increased the rate of purine synthesis de novo by 2.2- to 4.0-fold. Because glucagon infusion increased the rate of purine synthesis de novo in the presence of unchanged purine ribonucleotide concentrations, it is concluded that glucagon after infusion or in animals after a 70% hepatectomy is playing an anabolic role to increase the rate of purine synthesis de novo by increasing cAMP and 5-phosphoribosyl-1-pyrophosphate concentrations

Stretches of alternating pyrimidine/purines and purines are respectively linked with pathogenicity and growth temperature in prokaryotes

DEFF Research Database (Denmark)

Ussery, David; Bohlin, J; Hardy, SP

2009-01-01

BACKGROUND: The genomic fractions of purine (RR) and alternating pyrimidine/purine (YR) stretches of 10 base pairs or more, have been linked to genomic AT content, the formation of different DNA helices, strand-biased gene distribution, DNA structure, and more. Although some of these factors are ...... phyla. RR stretches are overrepresented in all phyla except for the Actinobacteria and beta-Proteobacteria. In contrast, YR tracts are underrepresented in all phyla except for the beta-Proteobacterial group. YR-stretches are associated with phylum, pathogenicity and habitat, whilst RR...

Heterosis and heritability estimates of purine alkaloids and ...

African Journals Online (AJOL)

Dry cocoa beans displayed high content of purine alkaloids (2.1 and 8.8 mg g-1 for caffein and theobromine, respectively), and polyphenols (25 and 2978 μg g-1 for catechin and epicatechin, respectively). Among the five cocoa clones, SNK16 was the highest in purine alkaloid (caffein and theobromin) and flavanol ...

Bias of purine stretches in sequenced chromosomes

DEFF Research Database (Denmark)

Ussery, David; Soumpasis, Dikeos Mario; Brunak, Søren

2002-01-01

/pur tracts was slightly less than expected, with an average of 0.8%. One of the most surprising findings is a clear difference in the length distributions of the regions studied between prokaryotes and eukaryotes. Whereas short-range correlations can explain the length distributions in prokaryotes......, in eukaryotes there is an abundance of long stretches of purines or alternating purine/pyrimidine tracts, which cannot be explained in this way; these sequences are likely to play an important role in eukaryotic chromosome organisation....

Isotopically labelled pyrimidines and purines

International Nuclear Information System (INIS)

Balaban, A.T.; Bally, I.

1987-01-01

Among the three diazines, pyrimidine is by far the most important one because its derivatives uracil, thymine and cytosine are constituents of the ubiquitous deoxynucleic acids (DNA) and ribonucleic acids (RNA). Other derivatives of pyrimidine without condensed rings include barbiturates, alloxan, orotic acid and thiamine or vitamin B 1 . From the polycyclic derivatives of pyrimidine such as pteridine, alloxazine, and purine, the latter, through its derivatives adenine and guanine complete the list of bases which occur in DNA and RNA: in addition, other purine derivatives such as hypoxanthine, xanthine, theobromine, theophylline, caffeine and uric acid are important natural products with biological activity. The paper presents methods for preparing isotopically labeled pyrimidines as well as purine derivatives. For convenience, the authors describe separately carbon-labeled with radioisotopes 11 C (T 1/2 = 20.3 min) and 14 C (T 1/2 = 5736 years) or the stable isotope 13 C (natural abundance 1.1%) and then hydrogen-labeled systems with the radioisotope 3 H ≡ T (T 1/2 = 12.346 years) or with the stable isotope 2 H ≡ D (natural abundance 0.015%). We do not separate stable from radioactive isotopes because the synthetic methods are identical for the same element; however, the introduction of hydrogen isotopes into organic molecules is often performed by reactions such as isotope exchange which cannot take place in the case of carbon isotopes

T.C.G triplet in an antiparallel purine.purine.pyrimidine DNA triplex. Conformational studies by NMR.

Science.gov (United States)

Dittrich, K; Gu, J; Tinder, R; Hogan, M; Gao, X

1994-04-12

The antiparallel purine.purine.pyrimidine DNA triplex, RRY6, which contains a T.C.G inverted triplet in the center of the sequence, was examined by proton and phosphorous two-dimensional NMR spectroscopy. The local conformation of the T.C.G triplet (T4.C11.G18) and the effect of this triplet on the global helical structure were analyzed in detail. The formation of the T.C.G triplet is confirmed by a set of cross-strand NOEs, including unusual cross-strand NOEs between the third strand and the pyrimidine strand as opposed to the purine strand of the duplex. NMR data suggest that the T.C.G triplet may be present in an equilibrium between a non-hydrogen-bonded form and a T(O4)-C(NH2) hydrogen-bonded form and that there is a distortion of the in-plane alignment of the three bases. The flanking G.G.C base triplets are well-defined on the 5'-side of T4, but somewhat interrupted on the 3'-side of T4. The effect of the third strand binding on the Watson-Crick duplex was probed by an NMR study of the free duplex RY6. NMR parameters are affected mostly around the T.C.G inversion site. The perturbations extend to at least two adjacent base triplets on either side. The binding of the third purine strand and the accommodation of a central T.C.G inversion in RRY6 does not require a readjustment in sugar pucker, which remains in the range of C2'-endo. 31P resonances of RRY6 distribute over a range of 2.2 ppm. The H-P coupling patterns of the third strand differ from those of the duplex. General spectral patterns defined by the marker protons of the RRY and YRY triplexes are compared.

Genetic Screen Reveals the Role of Purine Metabolism in Staphylococcus aureus Persistence to Rifampicin

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Rebecca Yee

2015-12-01

Full Text Available Chronic infections with Staphylococcus aureus such as septicemia, osteomyelitis, endocarditis, and biofilm infections are difficult to treat because of persisters. Despite many efforts in understanding bacterial persistence, the mechanisms of persister formation in S. aureus remain elusive. Here, we performed a genome-wide screen of a transposon mutant library to study the molecular mechanisms involved in persistence of community-acquired S. aureus. Screening of the library for mutants defective in persistence or tolerance to rifampicin revealed many genes involved in metabolic pathways that are important for antibiotic persistence. In particular, the identified mutants belonged to metabolic pathways involved in carbohydrate, amino acid, lipid, vitamin and purine biosynthesis. Five mutants played a role in purine biosynthesis and two mutants, purB, an adenylosuccinate lyase, and purM, a phosphoribosylaminoimidazole synthetase, were selected for further confirmation. Mutants purB and purM showed defective persistence compared to the parental strain USA300 in multiple stress conditions including various antibiotics, low pH, and heat stress. The defect in persistence was restored by complementation with the wildtype purB and purM gene in the respective mutants. These findings provide new insights into the mechanisms of persistence in S. aureus and provide novel therapeutic targets for developing more effective treatment for persistent infections due to S. aureus.

Estimation of rumen microbial-nitrogen of sheep using urinary excretion of purine derivatives

International Nuclear Information System (INIS)

Liu Dasen; Shan Anshan

2004-01-01

Determination of rumen microbial-nitrogen of sheep using urinary excretion of purine derivative was studied. Uric acid and xanthine + hypoxanthine were not affected by diets, but total purine derivatives for 1 mg borax/kg diet was higher than other diets (p<0.05). Microbial-nitrogen estimated from allantoin was not affected by diets, but that of 1 mg borax/kg diet estimated from total purine derivatives was higher than other diets (p<0.05). Microbial-nitrogen estimated from total purine derivatives was higher than that from allantoin

Effect of purines on calcium-independent acetylcholine release at the mouse neuromuscular junction.

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Veggetti, M; Muchnik, S; Losavio, A

2008-07-17

At the mouse neuromuscular junction, activation of adenosine A(1) and P2Y receptors inhibits acetylcholine release by an effect on voltage dependent calcium channels related to spontaneous and evoked secretion. However, an effect of purines upon the neurotransmitter-releasing machinery downstream of Ca(2+) influx cannot be ruled out. An excellent tool to study neurotransmitter exocytosis in a Ca(2+)-independent step is the hypertonic response. Intracellular recordings were performed on diaphragm fibers of CF1 mice to determine the action of the specific adenosine A(1) receptor agonist 2-chloro-N(6)-cyclopentyl-adenosine (CCPA) and the P2Y(12-13) agonist 2-methylthio-adenosine 5'-diphosphate (2-MeSADP) on the hypertonic response. Both purines significantly decreased such response (peak and area under the curve), and their effect was prevented by specific antagonists of A(1) and P2Y(12-13) receptors, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) and N-[2-(methylthioethyl)]-2-[3,3,3-trifluoropropyl]thio-5'-adenylic acid, monoanhydride with dichloromethylenebiphosphonic acid, tetrasodium salt (AR-C69931MX), respectively. Moreover, incubation of preparations only with the antagonists induced a higher response compared with controls, suggesting that endogenous ATP/ADP and adenosine are able to modulate the hypertonic response by activating their specific receptors. To search for the intracellular pathways involved in this effect, we studied the action of CCPA and 2-MeSADP in hypertonicity in the presence of inhibitors of several pathways. We found that the effect of CPPA was prevented by the calmodulin antagonist N-(6-aminohexil)-5-chloro-1-naphthalenesulfonamide hydrochloride (W-7) while that of 2-MeSADP was occluded by the protein kinase C antagonist chelerythrine and W-7. On the other hand, the inhibitors of protein kinase A (N-(2[pbromocinnamylamino]-ethyl)-5-isoquinolinesulfonamide, H-89) and phosphoinositide-3 kinase (PI3K) (2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran

Purine derivate content and amino acid profile in larval stages of three edible insects.

Science.gov (United States)

Bednářová, Martina; Borkovcová, Marie; Komprda, Tomáš

2014-01-15

Considering their high content of protein, insects are a valuable alternative protein source. However, no evaluation of their purine content has so far been done. High content of purine derivates may lead to the exclusion of such food from the diet of people with specific diseases. The aim of this study was to analyse the content of selected purine derivates and amino acid profile in the three insect species most often used for entomophagy in Europe and compare them with the purine content in egg white and chicken breast. The content of individual purine derivates and their total content were significantly dependent on insect species. The purine content in all three species was significantly higher (P < 0.05) than in egg white, but some values were significantly lower (P < 0.05) than in chicken breast. The total protein content was 548.9 g kg(-1) dry matter (DM) in mealworm (Tenebrio molitor), 551.6 g kg(-1) DM in superworm (Zophobas atratus) and 564.9 g kg(-1) DM in cricket (Gryllus assimilis). Larvae of mealworm and superworm are protein-rich and purine-low meat alternatives. In contrast, cricket nymphs are protein-rich and purine-rich and cannot be recommended for people with hyperuricemia or gout. © 2013 Society of Chemical Industry.

Biological treatment in clarificated purines pilot plant; Depuracion biologica en plant piloto del clarificado de los purines

Energy Technology Data Exchange (ETDEWEB)

Bosque Hernandez, J. L. del; Martin Sanchez, J. L. [Universidad de Salamanca (Spain)

2004-07-01

With the purpose of eliminating the environmental problem that suppose the residuals, denominated. Purines, it is necessary to treat them so that they can take advantage. for it, in the part I of the work, the treatment that facilitates the operation of separation of the solid in suspension of the raw purin that allows to decrease the matter organic present in the liquid phase, settled down as well as, the increase of the power fertilizer in the solid phase. The part II of this investigation have as purpose the treatment of the phase it liquidates obtained previously to adapt it for their use like water of industrial type and the solid phase as fertilizer. (Author) 5 refs.

Purine Restriction Induces Pronounced Translational Upregulation of the NT1 Adenosine/Pyrimidine Nucleoside Transporter in Leishmania major

OpenAIRE

Ortiz, Diana; Valdés, Raquel; Sanchez, Marco A.; Hayenga, Johanna; Elya, Carolyn; Detke, Siegfried; Landfear, Scott M.

2010-01-01

Leishmania and other parasitic protozoa are unable to synthesize purines de novo and are reliant upon purine nucleoside and nucleobase transporters to import preformed purines from their hosts. To study the roles of the four purine permeases NT1-NT4 in Leishmania major, null mutants in each transporter gene were prepared and the effect of each gene deletion on purine uptake was monitored. Deletion of the NT3 purine nucleobase transporter gene or both NT3 and the NT2 nucleoside transporter gen...

Distinct Purine Distribution in Carbonaceous Chondrites

Science.gov (United States)

Callahan, Michael P.; Smith, Karen E.; Cleaves, Henderson J.; Ruzicka, Josef; Stern, Jennifer C.; Glavin, Daniel P.; House, Christopher H.; Dworkin, Jason P.

2011-01-01

Carbonaceous chondrite meteorites are known to contain a diverse suite of organic compounds, many of which are essential components of biochemistry. Amino acids, which are the monomers of proteins, have been extensively studied in such meteorites (e.g. Botta and Bada 2002; Pizzarello et aI., 2006). The origin of amino acids in meteorites has been firmly established as extraterrestrial based on their detection typically as racemic mixtures of amino acids, the presence of many non-protein amino acids, and non-terrestrial values for compound-specific deuterium, carbon, and nitrogen isotopic measurements. In contrast to amino acids, nucleobases in meteorites have been far less studied. Nucleobases are substituted one-ring (pyrimidine) or two-ring (purine) nitrogen heterocyclic compounds and serve as the information carriers of nucleic acids and in numerous coenzymes. All of the purines (adenine, guanine, hypoxanthine, and xanthine) and pyrimidines (uracil) previously reported in meteorites are biologically common and could be interpreted as the result of terrestrial contamination (e.g. van del' Velden and Schwartz, 1974.) Unlike other meteoritic organics, there have been no observations of stochastic molecular diversity of purines and pyrimidines in meteorites, which has been a criterion for establishing extraterrestrial origin. Maltins et al. (2008) performed compound-specific stable carbon isotope measurements for uracil and xanthine in the Murchison meteorite. They assigned a non-terrestrial origin for these nucleobases; however, the possibility that interfering indigenous molecules (e.g. carboxylic acids) contributed to the 13C-enriched isotope values for these nucleobases cannot be completely ruled out. Thus, the origin of these meteoritic nucleobases has never been established unequivocally. Here we report on our investigation of extracts of II different carbonaceous chondrites covering various petrographic types (Cl, CM, and CR) and degrees of aqueous alteration

The crystal structure of the hexameric purine nucleoside phosphorylase from Bacillus subtilis in complex with adenosine

Energy Technology Data Exchange (ETDEWEB)

Giuseppe, P.O.; Meza, A.N.; Martins, N.H.; Santos, C.R.; Murakami, M.T. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil)

2012-07-01

Full text: Purine nucleoside phosphorylases (PNPs) play a key role in the purine-salvage pathway in both prokaryotes and eukaryotes. Its ribosyltransferase activity is of great biotechnological interest due to potential application in the synthesis of nucleoside analogues used in the treatment of antiviral infections and in anticancer chemotherapy. Trimeric PNPs are found mainly in vertebrates and are specific for 6-oxo-purines whereas hexameric PNPs are prevalent in prokaryotes and exhibit a broad range of substrates including 6-oxo and 6-amino purines. BsPNP233, the hexameric PNP from B. subtilis, is able to catalyze the bioconversion of ribavirin, an anti-viral drug, and is relatively thermostable, being a good target for industrial use. Here we report the crystal structures of BsPNP233 in the apo form and in complex with adenosine solved at 2.65 and 1.91 resolution, respectively. The apo and ligand-bound BsPNP233 subunits superposed with an overall r.m.s. deviation of 0.31 for all C{alpha} atoms, which suggests that no major conformational changes occur upon substrate binding. Based on the crystal structure of BsPNP233 in complex with adenosine we have defined the active site residues implicated in binding the ribose (H4{sup *}, R43{sup *}, M64, R87, E178, M179, E180) and the nitrogenous base (S90, C91, G92, S202, V177, F159). These residues are highly conserved among the bacterial hexameric PNPs, suggesting they share the same mode of interaction with the substrates. This work will probably contribute to a better understanding of the molecular basis for the broad substrate specificity of hexameric PNPs and to projects aiming the rational design of PNPs for industrial purposes. (author)

Experimental and theoretical dipole moments of purines in their ground and lowest excited singlet states

Science.gov (United States)

Aaron, Jean-Jacques; Diabou Gaye, Mame; Párkányi, Cyril; Cho, Nam Sook; Von Szentpály, László

1987-01-01

The ground-state dipole moments of seven biologically important purines (purine, 6-chloropurine, 6-mercaptopurine, hypoxanthine, theobromine, theophylline and caffeine) were determined at 25°C in acetic acid (all the above compounds with the exception of purine) and in ethyl acetate (purine, theophylline and caffeine). Because of its low solubility, it was not possible to measure the dipole moment of uric acid. The first excited singlet-state dipole moments were obtained on the basis of the Bakhshiev and Chamma—Viallet equations using the variation of the Stokes shift with the solvent dielectric constant-refractive index term. The theoretical dipole moments for all the purines listed above and including uric acid were calculated by combining the use of the PPP (π-LCI-SCF-MO) method for the π-contribution to the overall dipole moment with the σ-contribution obtained as a vector sum of the σbond moments and group moments. The experimental and theoretical values were compared with the data available in the literature for some of the purines under study. For several purines, the calculations were carried out for different tautomeric forms. Excited singlet-state dipole moments are smaller than the ground-state values by 0.8 to 2.2 Debye units for all purines under study with the exception of 6-chloropurine. The effects of the structure upon the ground- and excited-state dipole moments of the purines are discussed.

Anopheles gambiae Purine Nucleoside Phosphorylase: Catalysis, Structure, and Inhibition

Energy Technology Data Exchange (ETDEWEB)

Taylor,E.; Rinaldo-Matthis, A.; Li, L.; Ghanem, M.; Hazleton, K.; Cassera, M.; Almo, S.; Schramm, V.

2007-01-01

The purine salvage pathway of Anopheles gambiae, a mosquito that transmits malaria, has been identified in genome searches on the basis of sequence homology with characterized enzymes. Purine nucleoside phosphorylase (PNP) is a target for the development of therapeutic agents in humans and purine auxotrophs, including malarial parasites. The PNP from Anopheles gambiae (AgPNP) was expressed in Escherichia coli and compared to the PNPs from Homo sapiens (HsPNP) and Plasmodium falciparum (PfPNP). AgPNP has kcat values of 54 and 41 s-1 for 2'-deoxyinosine and inosine, its preferred substrates, and 1.0 s-1 for guanosine. However, the chemical step is fast for AgPNP at 226 s-1 for guanosine in pre-steady-state studies. 5'-Deaza-1'-aza-2'-deoxy-1'-(9-methylene)-Immucillin-H (DADMe-ImmH) is a transition-state mimic for a 2'-deoxyinosine ribocation with a fully dissociated N-ribosidic bond and is a slow-onset, tight-binding inhibitor with a dissociation constant of 3.5 pM. This is the tightest-binding inhibitor known for any PNP, with a remarkable Km/Ki* of 5.4 x 107, and is consistent with enzymatic transition state predictions of enhanced transition-state analogue binding in enzymes with enhanced catalytic efficiency. Deoxyguanosine is a weaker substrate than deoxyinosine, and DADMe-Immucillin-G is less tightly bound than DADMe-ImmH, with a dissociation constant of 23 pM for AgPNP as compared to 7 pM for HsPNP. The crystal structure of AgPNP was determined in complex with DADMe-ImmH and phosphate to a resolution of 2.2 Angstroms to reveal the differences in substrate and inhibitor specificity. The distance from the N1' cation to the phosphate O4 anion is shorter in the AgPNP{center_dot}DADMe-ImmH{center_dot}PO4 complex than in HsPNP{center_dot}DADMe-ImmH{center_dot}SO4, offering one explanation for the stronger inhibitory effect of DADMe-ImmH for AgPNP.

Versatile synthesis and biological evaluation of novel 3’-fluorinated purine nucleosides

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Hang Ren

2015-12-01

Full Text Available A unified synthetic strategy accessing novel 3'-fluorinated purine nucleoside derivatives and their biological evaluation were achieved. Novel 3’-fluorinated analogues were constructed from a common 3’-deoxy-3’-fluororibofuranose intermediate. Employing Suzuki and Stille cross-coupling reactions, fifteen 3’-fluororibose purine nucleosides 1–15 and eight 3’-fluororibose 2-chloro/2-aminopurine nucleosides 16–23 with various substituents at position 6 of the purine ring were efficiently synthesized. Furthermore, 3’-fluorine analogs of natural products nebularine and 6-methylpurine riboside were constructed via our convergent synthetic strategy. Synthesized nucleosides were tested against HT116 (colon cancer and 143B (osteosarcoma cancer tumor cell lines. We have demonstrated 3’-fluorine purine nucleoside analogues display potent tumor cell growth inhibition activity at sub- or low micromolar concentration.

Mechanical and chemical recycling of solid plastic waste.

Science.gov (United States)

Ragaert, Kim; Delva, Laurens; Van Geem, Kevin

2017-11-01

This review presents a comprehensive description of the current pathways for recycling of polymers, via both mechanical and chemical recycling. The principles of these recycling pathways are framed against current-day industrial reality, by discussing predominant industrial technologies, design strategies and recycling examples of specific waste streams. Starting with an overview on types of solid plastic waste (SPW) and their origins, the manuscript continues with a discussion on the different valorisation options for SPW. The section on mechanical recycling contains an overview of current sorting technologies, specific challenges for mechanical recycling such as thermo-mechanical or lifetime degradation and the immiscibility of polymer blends. It also includes some industrial examples such as polyethylene terephthalate (PET) recycling, and SPW from post-consumer packaging, end-of-life vehicles or electr(on)ic devices. A separate section is dedicated to the relationship between design and recycling, emphasizing the role of concepts such as Design from Recycling. The section on chemical recycling collects a state-of-the-art on techniques such as chemolysis, pyrolysis, fluid catalytic cracking, hydrogen techniques and gasification. Additionally, this review discusses the main challenges (and some potential remedies) to these recycling strategies and ground them in the relevant polymer science, thus providing an academic angle as well as an applied one. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enhanced activity of the purine nucleotide cycle of the exercising muscle in patients with hyperthyroidism.

Science.gov (United States)

Fukui, H; Taniguchi , S; Ueta, Y; Yoshida, A; Ohtahara, A; Hisatome, I; Shigemasa, C

2001-05-01

Myopathy frequently develops in patients with hyperthyroidism, but its precise mechanism is not clearly understood. In this study we focused on the purine nucleotide cycle, which contributes to ATP balance in skeletal muscles. To investigate purine metabolism in muscles, we measured metabolites related to the purine nucleotide cycle using the semiischemic forearm test. We examined the following four groups: patients with untreated thyrotoxic Graves' disease (untreated group), patients with Graves' disease treated with methimazole (treated group), patients in remission (remission group), and healthy volunteers (control group). To trace the glycolytic process, we measured glycolytic metabolites (lactate and pyruvate) as well as purine metabolites (ammonia and hypoxanthine). In the untreated group, the levels of lactate, pyruvate, and ammonia released were remarkably higher than those in the control group. Hypoxanthine release also increased in the untreated group, but the difference among the patient groups was not statistically significant. The accelerated purine catabolism did not improve after 3 months of treatment with methimazole, but it was completely normalized in the remission group. This indicated that long-term maintenance of thyroid function was necessary for purine catabolism to recover. We presume that an unbalanced ATP supply or conversion of muscle fiber type may account for the acceleration of the purine nucleotide cycle under thyrotoxicosis. Such acceleration of the purine nucleotide cycle is thought to be in part a protective mechanism against a rapid collapse of the ATP energy balance in exercising muscles of patients with hyperthyroidism.

Purine Bases in Blood Plasma of Patients with Chronic Pulmonary Diseases

Directory of Open Access Journals (Sweden)

Larissa E. Muravluyova

2012-09-01

Full Text Available The article is focused on the study of purine bases and intermediates of purine catabolism in plasma of patients with chronic obstructive bronchitis and idiopathic interstitial pneumonia. Decrease of adenine and hypoxantine in plasma of patients with idiopathic interstitial pneumonia was registered. Increase of guanine in plasma of patients with chronic obstructive pulmonary disease was established.

Purines and Neuronal Excitability: Links to the Ketogenic Diet

Science.gov (United States)

Masino, SA; Kawamura, M; Ruskin, DN; Geiger, JD; Boison, D

2011-01-01

ATP and adenosine are purines that play dual roles in cell metabolism and neuronal signaling. Acting at the A1 receptor (A1R) subtype, adenosine acts directly on neurons to inhibit excitability and is a powerful endogenous neuroprotective and anticonvulsant molecule. Previous research showed an increase in ATP and other cell energy parameters when an animal is administered a ketogenic diet, an established metabolic therapy to reduce epileptic seizures, but the relationship among purines, neuronal excitability and the ketogenic diet was unclear. Recent work in vivo and in vitro tested the specific hypothesis that adenosine acting at A1Rs is a key mechanism underlying the success of ketogenic diet therapy and yielded direct evidence linking A1Rs to the antiepileptic effects of a ketogenic diet. Specifically, an in vitro mimic of a ketogenic diet revealed an A1R-dependent metabolic autocrine hyperpolarization of hippocampal neurons. In parallel, applying the ketogenic diet in vivo to transgenic mouse models with spontaneous electrographic seizures revealed that intact A1Rs are necessary for the seizure-suppressing effects of the diet. This is the first direct in vivo evidence linking A1Rs to the antiepileptic effects of a ketogenic diet. Other predictions of the relationship between purines and the ketogenic diet are discussed. Taken together, recent research on the role of purines may offer new opportunities for metabolic therapy and insight into its underlying mechanisms. PMID:21880467

Direct N9-arylation of purines with aryl halides

DEFF Research Database (Denmark)

Larsen, Anders Foller; Ulven, Trond

2014-01-01

An efficient method for N-arylation of purines is reported. The N-arylation is catalysed by Cu(i) and 4,7-bis(2-hydroxyethylamino)-1,10-phenanthroline (BHPhen) in aqueous DMF or ethanol. The reaction generally proceeds with high selectivity for the N(9)-position.......An efficient method for N-arylation of purines is reported. The N-arylation is catalysed by Cu(i) and 4,7-bis(2-hydroxyethylamino)-1,10-phenanthroline (BHPhen) in aqueous DMF or ethanol. The reaction generally proceeds with high selectivity for the N(9)-position....

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

Science.gov (United States)

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

2007-05-01

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

Purines and Carotid Body: New Roles in Pathological Conditions

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Silvia V. Conde

2017-12-01

Full Text Available It is known that adenosine and adenosine-5′-triphosphate (ATP are excitatory mediators involved in carotid body (CB hypoxic signaling. The CBs are peripheral chemoreceptors classically defined by O2, CO2, and pH sensors. When hypoxia activates the CB, it induces the release of neurotransmitters from chemoreceptor cells leading to an increase in the action potentials frequency at the carotid sinus nerve (CSN. This increase in the firing frequency of the CSN is integrated in the brainstem to induce cardiorespiratory compensatory responses. In the last decade several pathologies, as, hypertension, diabetes, obstructive sleep apnea and heart failure have been associated with CB overactivation. In the first section of the present manuscript we review in a concise manner fundamental aspects of purine metabolism. The second section is devoted to the role of purines on the hypoxic response of the CB, providing the state-of-the art for the presence of adenosine and ATP receptors in the CB; for the role of purines at presynaptic level in CB chemoreceptor cells, as well as, its metabolism and regulation; at postsynaptic level in the CSN activity; and on the ventilatory responses to hypoxia. Recently, we have showed that adenosine is involved in CB hypersensitization during chronic intermittent hypoxia (CIH, which mimics obstructive sleep apnea, since caffeine, a non-selective adenosine receptor antagonist that inhibits A2A and A2B adenosine receptors, decreased CSN chemosensory activity in animals subjected to CIH. Apart from this involvement of adenosine in CB sensitization in sleep apnea, it was recently found that P2X3 ATP receptor in the CB contributes to increased chemoreflex hypersensitivity and hypertension in spontaneously hypertension rats. Therefore the last section of this manuscript is devoted to review the recent findings on the role of purines in CB-mediated pathologies as hypertension, diabetes and sleep apnea emphasizing the potential

The GPRC6A Receptor displays Constitutive Internalization and Sorting to the Slow Recycling Pathway

DEFF Research Database (Denmark)

Jacobsen, Stine Engesgaard; Ammendrup-Johnsen, Ina; Jansen, Anna Mai

2017-01-01

The class C G protein-coupled receptor GPRC6A is a putative nutrient sensing receptor and represents a possible new drug target in metabolic disorders. However, the specific physiological role of this receptor has yet to be identified, and the mechanisms regulating its activity and cell surface...... availability also remain enigmatic. In the present study, we investigated the trafficking properties of GPRC6A by use of both a classical antibody feeding internalization assay in which cells were visualized using confocal microscopy and a novel internalization assay that is based on real-time measurements...... slow recycling pathway, which may be responsible for ensuring a persistent pool of GPRC6A receptors at the cell surface despite chronic agonist exposure. Distinct trafficking pathways have been reported for several of the class C receptors, and our results thus substantiate that non...

Enhancement of Nucleoside Production in Hirsutella sinensis Based on Biosynthetic Pathway Analysis

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Liu, Zhi-Qiang; Zhang, Bo; Lin, Shan; Baker, Peter James; Chen, Mao-Sheng; Xue, Ya-Ping; Wu, Hui; Xu, Feng; Yuan, Shui-Jin; Teng, Yi; Wu, Ling-Fang

2017-01-01

To enhance nucleoside production in Hirsutella sinensis, the biosynthetic pathways of purine and pyrimidine nucleosides were constructed and verified. The differential expression analysis showed that purine nucleoside phosphorylase, inosine monophosphate dehydrogenase, and guanosine monophosphate synthase genes involved in purine nucleotide biosynthesis were significantly upregulated 16.56-fold, 8-fold, and 5.43-fold, respectively. Moreover, dihydroorotate dehydrogenase, uridine nucleosidase, uridine/cytidine monophosphate kinase, and inosine triphosphate pyrophosphatase genes participating in pyrimidine nucleoside biosynthesis were upregulated 4.53-fold, 10.63-fold, 4.26-fold, and 5.98-fold, respectively. To enhance the nucleoside production, precursors for synthesis of nucleosides were added based on the analysis of biosynthetic pathways. Uridine and cytidine contents, respectively, reached 5.04 mg/g and 3.54 mg/g when adding 2 mg/mL of ribose, resulting in an increase of 28.6% and 296% compared with the control, respectively. Meanwhile, uridine and cytidine contents, respectively, reached 10.83 mg/g 2.12 mg/g when adding 0.3 mg/mL of uracil, leading to an increase of 176.3% and 137.1%, respectively. This report indicated that fermentation regulation was an effective way to enhance the nucleoside production in H. sinensis based on biosynthetic pathway analysis. PMID:29333435

Purine restriction induces pronounced translational upregulation of the NT1 adenosine/pyrimidine nucleoside transporter in Leishmania major.

Science.gov (United States)

Ortiz, Diana; Valdés, Raquel; Sanchez, Marco A; Hayenga, Johanna; Elya, Carolyn; Detke, Siegfried; Landfear, Scott M

2010-10-01

Leishmania and other parasitic protozoa are unable to synthesize purines de novo and are reliant upon purine nucleoside and nucleobase transporters to import preformed purines from their hosts. To study the roles of the four purine permeases NT1-NT4 in Leishmania major, null mutants in each transporter gene were prepared and the effect of each gene deletion on purine uptake was monitored. Deletion of the NT3 purine nucleobase transporter gene or both NT3 and the NT2 nucleoside transporter gene resulted in pronounced upregulation of adenosine and uridine uptake mediated by the NT1 permease and also induced up to a 200-fold enhancement in the level of the NT1 protein but not mRNA. A similar level of upregulation of NT1 was achieved in wild-type promastigotes that were transferred to medium deficient in purines. Pulse labelling and treatment of cells with the translation inhibitor cycloheximide revealed that control of NT1 expression occurs primarily at the level of translation and not protein turnover. These observations imply the existence of a translational control mechanism that enhances the ability of Leishmania parasites to import essential purines when they are present at limiting concentrations. © 2010 Blackwell Publishing Ltd.

Heterogeneity and dynamics of the ligand recognition mode in purine-sensing riboswitches.

Science.gov (United States)

Jain, Niyati; Zhao, Liang; Liu, John D; Xia, Tianbing

2010-05-04

High-resolution crystal structures and biophysical analyses of purine-sensing riboswitches have revealed that a network of hydrogen bonding interactions appear to be largey responsible for discrimination of cognate ligands against structurally related compounds. Here we report that by using femtosecond time-resolved fluorescence spectroscopy to capture the ultrafast decay dynamics of the 2-aminopurine base as the ligand, we have detected the presence of multiple conformations of the ligand within the binding pockets of one guanine-sensing and two adenine-sensing riboswitches. All three riboswitches have similar conformational distributions of the ligand-bound state. The known crystal structures represent the global minimum that accounts for 50-60% of the population, where there is no significant stacking interaction between the ligand and bases of the binding pocket, but the hydrogen-bonding cage collectively provides an electronic environment that promotes an ultrafast ( approximately 1 ps) charge transfer pathway. The ligand also samples multiple conformations in which it significantly stacks with either the adenine or the uracil bases of the A21-U75 and A52-U22 base pairs that form the ceiling and floor of the binding pocket, respectively, but favors the larger adenine bases. These alternative conformations with well-defined base stacking interactions are approximately 1-1.5 kcal/mol higher in DeltaG degrees than the global minimum and have distinct charge transfer dynamics within the picosecond to nanosecond time regime. Inside the pocket, the purine ligand undergoes dynamic motion on the low nanosecond time scale, sampling the multiple conformations based on time-resolved anisotropy decay dynamics. These results allowed a description of the energy landscape of the bound ligand with intricate details and demonstrated the elastic nature of the ligand recognition mode by the purine-sensing riboswitches, where there is a dynamic balance between hydrogen bonding

Trisubstituted purine inhibitors of PDGFRα and their antileukemic activity in the human eosinophilic cell line EOL-1.

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Malínková, Veronika; Řezníčková, Eva; Jorda, Radek; Gucký, Tomáš; Kryštof, Vladimír

2017-12-15

Inhibition of protein kinases is a validated concept for pharmacological intervention in cancers. Many kinase inhibitors have been approved for clinical use, but their practical application is often limited. Here, we describe a collection of 23 novel 2,6,9-trisubstituted purine derivatives with nanomolar inhibitory activities against PDGFRα, a receptor tyrosine kinase often found constitutively activated in various tumours. The compounds demonstrated strong and selective cytotoxicity in the human eosinophilic leukemia cell line EOL-1, whereas several other cell lines were substantially less sensitive. The cytotoxicity in EOL-1, which is known to express the FIP1L1-PDGFRA fusion gene encoding an oncogenic kinase, correlated significantly with PDGFRα inhibition. EOL-1 cells treated with the compounds also exhibited dose-dependent inhibition of PDGFRα autophosphorylation and suppression of its downstream signaling pathways with concomitant G 1 phase arrest, confirming the proposed mechanism of action. Our results show that substituted purines can be used as platforms for preparing tyrosine kinase inhibitors with specific activity towards eosinophilic leukemia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Functionalized Solid Electrodes for Electrochemical Biosensing of Purine Nucleobases and Their Analogues: A Review

Czech Academy of Sciences Publication Activity Database

Sharma, V.K.; Jelen, František; Trnková, L.

2015-01-01

Roč. 15, č. 1 (2015), s. 1564-1600 ISSN 1424-8220 Institutional support: RVO:68081707 Keywords : purine derivatives * electrochemistry of purines * carbon electrode Subject RIV: BO - Biophysics Impact factor: 2.033, year: 2015

Genetics Home Reference: purine nucleoside phosphorylase deficiency

Science.gov (United States)

... the expand/collapse boxes. Description Purine nucleoside phosphorylase deficiency is one of several disorders that damage the immune system and cause severe combined immunodeficiency (SCID). People with SCID lack virtually all immune protection from foreign invaders such as bacteria, viruses, and ...

Genome-wide screening for genes whose deletions confer sensitivity to mutagenic purine base analogs in yeast

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Kozmin Stanislav G

2005-06-01

Full Text Available Abstract Background N-hydroxylated base analogs, such as 6-hydroxylaminopurine (HAP and 2-amino-6-hydroxylaminopurine (AHA, are strong mutagens in various organisms due to their ambiguous base-pairing properties. The systems protecting cells from HAP and related noncanonical purines in Escherichia coli include specialized deoxyribonucleoside triphosphatase RdgB, DNA repair endonuclease V, and a molybdenum cofactor-dependent system. Fewer HAP-detoxification systems have been identified in yeast Saccharomyces cerevisiae and other eukaryotes. Cellular systems protecting from AHA are unknown. In the present study, we performed a genome-wide search for genes whose deletions confer sensitivity to HAP and AHA in yeast. Results We screened the library of yeast deletion mutants for sensitivity to the toxic and mutagenic action of HAP and AHA. We identified novel genes involved in the genetic control of base analogs sensitivity, including genes controlling purine metabolism, cytoskeleton organization, and amino acid metabolism. Conclusion We developed a method for screening the yeast deletion library for sensitivity to the mutagenic and toxic action of base analogs and identified 16 novel genes controlling pathways of protection from HAP. Three of them also protect from AHA.

(13)C metabolic flux analysis in neurons utilizing a model that accounts for hexose phosphate recycling within the pentose phosphate pathway.

Science.gov (United States)

Gebril, Hoda M; Avula, Bharathi; Wang, Yan-Hong; Khan, Ikhlas A; Jekabsons, Mika B

2016-02-01

Glycolysis, mitochondrial substrate oxidation, and the pentose phosphate pathway (PPP) are critical for neuronal bioenergetics and oxidation-reduction homeostasis, but quantitating their fluxes remains challenging, especially when processes such as hexose phosphate (i.e., glucose/fructose-6-phosphate) recycling in the PPP are considered. A hexose phosphate recycling model was developed which exploited the rates of glucose consumption, lactate production, and mitochondrial respiration to infer fluxes through the major glucose consuming pathways of adherent cerebellar granule neurons by replicating [(13)C]lactate labeling from metabolism of [1,2-(13)C2]glucose. Flux calculations were predicated on a steady-state system with reactions having known stoichiometries and carbon atom transitions. Non-oxidative PPP activity and consequent hexose phosphate recycling, as well as pyruvate production by cytoplasmic malic enzyme, were optimized by the model and found to account for 28 ± 2% and 7.7 ± 0.2% of hexose phosphate and pyruvate labeling, respectively. From the resulting fluxes, 52 ± 6% of glucose was metabolized by glycolysis, compared to 19 ± 2% by the combined oxidative/non-oxidative pentose cycle that allows for hexose phosphate recycling, and 29 ± 8% by the combined oxidative PPP/de novo nucleotide synthesis reactions. By extension, 62 ± 6% of glucose was converted to pyruvate, the metabolism of which resulted in 16 ± 1% of glucose oxidized by mitochondria and 46 ± 6% exported as lactate. The results indicate a surprisingly high proportion of glucose utilized by the pentose cycle and the reactions synthesizing nucleotides, and exported as lactate. While the in vitro conditions to which the neurons were exposed (high glucose, no lactate or other exogenous substrates) limit extrapolating these results to the in vivo state, the approach provides a means of assessing a number of metabolic fluxes within the context of hexose phosphate recycling in the PPP from a

The metabolism of histamine in the Drosophila optic lobe involves an ommatidial pathway: β-alanine recycles through the retina

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Borycz, Janusz; Borycz, Jolanta A.; Edwards, Tara N.; Boulianne, Gabrielle L.; Meinertzhagen, Ian A.

2012-01-01

SUMMARY Flies recycle the photoreceptor neurotransmitter histamine by conjugating it to β-alanine to form β-alanyl-histamine (carcinine). The conjugation is regulated by Ebony, while Tan hydrolyses carcinine, releasing histamine and β-alanine. In Drosophila, β-alanine synthesis occurs either from uracil or from the decarboxylation of aspartate but detailed roles for the enzymes responsible remain unclear. Immunohistochemically detected β-alanine is present throughout the fly’s entire brain, and is enhanced in the retina especially in the pseudocone, pigment and photoreceptor cells of the ommatidia. HPLC determinations reveal 10.7 ng of β-alanine in the wild-type head, roughly five times more than histamine. When wild-type flies drink uracil their head β-alanine increases more than after drinking l-aspartic acid, indicating the effectiveness of the uracil pathway. Mutants of black, which lack aspartate decarboxylase, cannot synthesize β-alanine from l-aspartate but can still synthesize it efficiently from uracil. Our findings demonstrate a novel function for pigment cells, which not only screen ommatidia from stray light but also store and transport β-alanine and carcinine. This role is consistent with a β-alanine-dependent histamine recycling pathway occurring not only in the photoreceptor terminals in the lamina neuropile, where carcinine occurs in marginal glia, but vertically via a long pathway that involves the retina. The lamina’s marginal glia are also a hub involved in the storage and/or disposal of carcinine and β-alanine. PMID:22442379

Research on urinary excretion of purine derivatives in ruminants: Past, present and future

International Nuclear Information System (INIS)

Chen, X.B.; Orskov, E.R.

2004-01-01

Research on urinary excretion of purine derivatives (PD), namely allantoin, uric acid, xanthine and hypoxanthine, in ruminants have been carried out with an objective to use the excretion of these purine metabolites as a parameter to estimate the intestinal flow of microbial protein. This paper reviews the published literature, from the first paper in 1931 to the current date. The current status of understanding in some key topics is discussed. The topics include: endogenous excretion, modelling the response of PD excretion to purine absorption, calculation of microbial N supply from PD excretion, use of spot urine measurement, possible use of plasma or milk PD as an alterative index, and applications in ruminant nutrition research. This review also covers the current understanding of PD excretion in different animal species, including sheep, cattle, goats, buffaloes, llamas, camels, yak and deer. Progress in analytical methods for the determination of purine derivatives is also discussed. Finally, areas of future research are highlighted. The paper stresses the need for more studies on metabolism of PD in the tissue, the kinetics of PD in the blood and physiological processes of renal excretion, so as to understand better the mechanism that accounts for the between-species and within species variation in PD excretion. Development of simpler and more rapid methods for defining the endogenous excretion and purine input-output relationship is also an area for future work. (author)

Partition coefficients of some purine derivatives and its application to pharmacokinetics.

Science.gov (United States)

Chrzanowska, M; Sobiak, J; Kuehn, M; Dorawa, E; Hermann, T

2009-12-01

Metazathioprine (MAZA), a methylated derivative of azathioprine (AZA), demonstrated the greatest values of apparent and specific partition coefficients in n-octanol/phosphate buffer at pH 5.7 and pH 7.4 among purine derivatives such as 6-mercaptopurine (6-MP), 6-thioguanine (6-TG) and AZA. Introduction of a methyl group into the imidazole ring of AZA increases lipophilic properties of MAZA compared to AZA. Mass balance of purine derivatives in n-octanol and in phosphate buffer indicated their chemical stability in those media.

1,3,5-Triazine-based analogues of purine: from isosteres to privileged scaffolds in medicinal chemistry.

Science.gov (United States)

Lim, Felicia Phei Lin; Dolzhenko, Anton V

2014-10-06

Purines can be considered as the most ubiquitous and functional N-heterocyclic compounds in nature. Structural modifications of natural purines, particularly using isosteric ring systems, have been in the focus of many drug discovery programs. Fusion of 1,3,5-triazine ring with pyrrole, pyrazole, imidazole, 1,2,3-triazole or 1,2,4-triazole results in seven bicyclic heterocyclic systems isosteric to purine. Application of the isosterism concept for the development of new compounds with therapeutic potential in areas involving purinergic regulation or purine metabolism led to significant advances in medicinal chemistry of the azolo[1,3,5]triazines. These 1,3,5-triazine-based purine-like scaffolds significantly increase level of molecular diversity and allow covering chemical space in the important areas of medicinal chemistry. Some of these azolo[1,3,5]triazine systems have become privileged scaffolds in the development of inhibitors of various kinases, phosphodiesterase, xanthine oxidase, and thymidine phosphorylase, antagonists of adenosine and corticotropin-releasing hormone receptors, anticancer and antiviral agents. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Mechanism of recycling of post-termination ribosomal complexes in ...

Indian Academy of Sciences (India)

Madhu

all pathway of ribosome recycling in eubacteria with especial reference to the important role of the initiation factor ... [Seshadri A and Varshney U 2006 Mechanism of recycling of post-termination ribosomal complexes in eubacteria: a new role of initiation factor 3 .... RRF binding results in a remarkable conformational change.

Two purine nucleoside phosphorylases in Bacillus subtilis. Purification and some properties of the adenosine-specific phosphorylase

DEFF Research Database (Denmark)

Jensen, Kaj Frank

1978-01-01

Two purine nucleoside phosphorylases (purine-nucleoside:orthophosphate ribosyltransferase, EC 2.4.2.1) were purified from vegetative Bacillus subtilis cells. One enzyme, inosine-guanosine phosphorylase, showed great similarity to the homologous enzyme of Bacillus cereus. It appeared...

Unconventional secretion of tissue transglutaminase involves phospholipid-dependent delivery into recycling endosomes.

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Evgeny A Zemskov

2011-04-01

Full Text Available Although endosomal compartments have been suggested to play a role in unconventional protein secretion, there is scarce experimental evidence for such involvement. Here we report that recycling endosomes are essential for externalization of cytoplasmic secretory protein tissue transglutaminase (tTG. The de novo synthesized cytoplasmic tTG does not follow the classical ER/Golgi-dependent secretion pathway, but is targeted to perinuclear recycling endosomes, and is delivered inside these vesicles prior to externalization. On its route to the cell surface tTG interacts with internalized β1 integrins inside the recycling endosomes and is secreted as a complex with recycled β1 integrins. Inactivation of recycling endosomes, blocking endosome fusion with the plasma membrane, or downregulation of Rab11 GTPase that controls outbound trafficking of perinuclear recycling endosomes, all abrogate tTG secretion. The initial recruitment of cytoplasmic tTG to recycling endosomes and subsequent externalization depend on its binding to phosphoinositides on endosomal membranes. These findings begin to unravel the unconventional mechanism of tTG secretion which utilizes the long loop of endosomal recycling pathway and indicate involvement of endosomal trafficking in non-classical protein secretion.

The radiation chemistry of the purine bases within DNA and related model compounds

International Nuclear Information System (INIS)

Cadet, J.; Berger, M.; Shaw, A.

1986-01-01

Both the direct and indirect effects of ionizing radiations are believed to contribute to the chemical changes induced in cellular DNA. Relevant information on the possible degradation pathways has been provided by studies using DNA model compounds, the major proportion of which have focused on pyrimidine components and sugar derivatives. With the development of powerful analytical tools such as high performance liquid chromatography and soft ionization mass spectrometry techniques, progress has recently been made in the elucidation of the nature of the radiation-induced chemical modifications of purine bases in DNA and related nucleosides and nucleotides. This short review details recent aspects of the radiation-induced degradation of adenine and guanine bases in DNA and its model compounds as the result of both direct and indirect effects. 11 refs., 2 figs., 1 tab

Identification of genes containing expanded purine repeats in the human genome and their apparent protective role against cancer.

Science.gov (United States)

Singh, Himanshu Narayan; Rajeswari, Moganty R

2016-01-01

Purine repeat sequences present in a gene are unique as they have high propensity to form unusual DNA-triple helix structures. Friedreich's ataxia is the only human disease that is well known to be associated with DNA-triplexes formed by purine repeats. The purpose of this study was to recognize the expanded purine repeats (EPRs) in human genome and find their correlation with cancer pathogenesis. We developed "PuRepeatFinder.pl" algorithm to identify non-overlapping EPRs without pyrimidine interruptions in the human genome and customized for searching repeat lengths, n ≥ 200. A total of 1158 EPRs were identified in the genome which followed Wakeby distribution. Two hundred and ninety-six EPRs were found in geneic regions of 282 genes (EPR-genes). Gene clustering of EPR-genes was done based on their cellular function and a large number of EPR-genes were found to be enzymes/enzyme modulators. Meta-analysis of 282 EPR-genes identified only 63 EPR-genes in association with cancer, mostly in breast, lung, and blood cancers. Protein-protein interaction network analysis of all 282 EPR-genes identified proteins including those in cadherins and VEGF. The two observations, that EPRs can induce mutations under malignant conditions and that identification of some EPR-gene products in vital cell signaling-mediated pathways, together suggest the crucial role of EPRs in carcinogenesis. The new link between EPR-genes and their functionally interacting proteins throws a new dimension in the present understanding of cancer pathogenesis and can help in planning therapeutic strategies. Validation of present results using techniques like NGS is required to establish the role of the EPR genes in cancer pathology.

The immediate nucleotide precursor, guanosine triphosphate, in the riboflavin biosynthetic pathway

International Nuclear Information System (INIS)

Mitsuda, Hisateru; Nakajima, Kenji; Nadamoto, Tomonori

1977-01-01

In the present paper, the nucleotide precursor of riboflavin was investigated by experiments with labeled purines using non-growing cells of Eremothecium ashbyii. The added purines, at 10 -4 M, were effectively incorporated into riboflavin at an early stage of riboflavin biosynthesis under the experimental conditions. In particular, both labeled xanthine and labeled guanine were specifically transported to guanosine nucleotides, GMP, GDP, GDP-Mannose and GTP, in the course of the riboflavin biosynthesis. A comparison of specific activities of labeled guanosine nucleotides and labeled riboflavin indicated that the nucleotide precursor of riboflavin is guanosine triphosphate. From the results obtained, a biosynthetic pathway of riboflavin is proposed. (auth.)

Inhibition and Structure of Trichomonas vaginalis Purine Nucleoside Phosphorylase with Picomolar Transition State Analogues

Energy Technology Data Exchange (ETDEWEB)

Rinaldo-Matthis,A.; Wing, C.; Ghanem, M.; Deng, H.; Wu, P.; Gupta, A.; Tyler, P.; Evans, G.; Furneaux, R.; et al.

2007-01-01

Trichomonas vaginalis is a parasitic protozoan purine auxotroph possessing a unique purine salvage pathway consisting of a bacterial type purine nucleoside phosphorylase (PNP) and a purine nucleoside kinase. Thus, T. vaginalis PNP (TvPNP) functions in the reverse direction relative to the PNPs in other organisms. Immucillin-A (ImmA) and DADMe-Immucillin-A (DADMe-ImmA) are transition stte mimics of adenosine with geometric and electrostatic features that resemble early and late transition states of adenosine at the transition state stabilized by TvPNP. ImmA demonstrates slow-onset tight-binding inhibition with TvPNP, to give an equilibrium dissociation constant of 87 pM, an inhibitor release half-time of 17.2 min, and a K{sub m}/K{sub d} ratio of 70,100. DADMe-ImmA resembles a late ribooxacarbenium ion transition state for TvPNP to give a dissociation constant of 30 pM, an inhibitor release half-time of 64 min, and a K{sub m}/K{sub d} ratio of 203,300. The tight binding of DADMe-ImmA supports a late S{sub N}1 transition state. Despite their tight binding to TvPNP, ImmA and DADMe-ImmA are weak inhibitors of human and P. falciparum PNPs. The crystal structures of the TvPNP-ImmA{center_dot}PO{sub 4} and TvPNP{center_dot}DADMe-ImmA{center_dot}PO{sub 4} ternary complexes differ from previous structures with substrate anologues. The tight binding with DADMe-ImmA is in part due to a 2.7 {angstrom} ionic interaction between a PO{sub 4} oxygen and the N1 cation of the hydroxypyrrolidine and is weaker in the TvPNP{center_dot}ImmA{center_dot}PO{sub 4} structure at 3.5 {angstrom}. However, the TvPNP{center_dot}ImmA{center_dot}PO{sub 4} structure includes hydrogen bonds between the 2'-hydroxyl and the protein that are not present in TvPNP{center_dot}DADMe-ImmA{center_dot}PO{sub 4}. These structures explain why DADMe-ImmA binds tighter than ImmA. Immucillin-H is a 12 nM inhibitor of TvPNP but a 56 pM inhibitor of human PNP. And this difference is explained by isotope

Functionalized Solid Electrodes for Electrochemical Biosensing of Purine Nucleobases and Their Analogues: A Review

Science.gov (United States)

Sharma, Vimal Kumar; Jelen, Frantisek; Trnkova, Libuse

2015-01-01

Interest in electrochemical analysis of purine nucleobases and few other important purine derivatives has been growing rapidly. Over the period of the past decade, the design of electrochemical biosensors has been focused on achieving high sensitivity and efficiency. The range of existing electrochemical methods with carbon electrode displays the highest rate in the development of biosensors. Moreover, modification of electrode surfaces based on nanomaterials is frequently used due to their extraordinary conductivity and surface to volume ratio. Different strategies for modifying electrode surfaces facilitate electron transport between the electrode surface and biomolecules, including DNA, oligonucleotides and their components. This review aims to summarize recent developments in the electrochemical analysis of purine derivatives, as well as discuss different applications. PMID:25594595

Functionalized Solid Electrodes for Electrochemical Biosensing of Purine Nucleobases and Their Analogues: A Review

Directory of Open Access Journals (Sweden)

Vimal Kumar Sharma

2015-01-01

Full Text Available Interest in electrochemical analysis of purine nucleobases and few other important purine derivatives has been growing rapidly. Over the period of the past decade, the design of electrochemical biosensors has been focused on achieving high sensitivity and efficiency. The range of existing electrochemical methods with carbon electrode displays the highest rate in the development of biosensors. Moreover, modification of electrode surfaces based on nanomaterials is frequently used due to their extraordinary conductivity and surface to volume ratio. Different strategies for modifying electrode surfaces facilitate electron transport between the electrode surface and biomolecules, including DNA, oligonucleotides and their components. This review aims to summarize recent developments in the electrochemical analysis of purine derivatives, as well as discuss different applications.

An Expanding Role For Purine Uptake Permease (PUP -like Transporters In Plant Secondary Metabolism.

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John G. Jelesko

2012-05-01

Full Text Available For the past decade, our understanding of the plant purine uptake permease (PUP transporter family of was primarily oriented on purine nucleobase substrates and their tissue-specific expression patterns in Arabidopsis. However, a tobacco PUP-like homolog demonstrating nicotine uptake permease (NUP activity was recently shown to affect both nicotine metabolism and root cell growth. These new findings expand the physiological role for PUP-like transporters to include plant secondary metabolism. Molecular evolution analyses of PUP-like transporters indicate they are distinct group within an ancient super family of drug and metabolite transporters (DMTs. The PUP-like family originated during terrestrial plant evolution sometime between the bryophytes and the lycophytes. A phylogenetic analysis indicates that the PUP-like transporters were likely were derived from a pre-existing nucleotide sugar transporter family within the DMT super family. Within the lycophyte Selaginella, there are three paralogous groups of PUP-like transporters. One of the three PUP-like paralogous groups showed an extensive pattern of gene duplication and diversification within the angiosperm lineage, whereas the other two more ancestral PUP-like paralogous groups did not. Biochemical characterization of four closely-related PUP-like paralogs together with model-based phylogenetic analyses indicate both subfunctionalization and neofunctionalization during the molecular evolution of angiosperm PUP-like transporters. These findings suggest that members of the PUP-like family of DMT transporters are likely involved in diverse primary and secondary plant metabolic pathways.

The Purine-Utilizing Bacterium Clostridium acidurici 9a: A Genome-Guided Metabolic Reconsideration

OpenAIRE

Hartwich, Katrin; Poehlein, Anja; Daniel, Rolf

2012-01-01

Clostridium acidurici is an anaerobic, homoacetogenic bacterium, which is able to use purines such as uric acid as sole carbon, nitrogen, and energy source. Together with the two other known purinolytic clostridia C. cylindrosporum and C. purinilyticum, C. acidurici serves as a model organism for investigation of purine fermentation. Here, we present the first complete sequence and analysis of a genome derived from a purinolytic Clostridium. The genome of C. acidurici 9a consists ...

Plasma Membrane-Located Purine Nucleotide Transport Proteins Are Key Components for Host Exploitation by Microsporidian Intracellular Parasites

Science.gov (United States)

Heinz, Eva; Hacker, Christian; Dean, Paul; Mifsud, John; Goldberg, Alina V.; Williams, Tom A.; Nakjang, Sirintra; Gregory, Alison; Hirt, Robert P.; Lucocq, John M.; Kunji, Edmund R. S.; Embley, T. Martin

2014-01-01

Microsporidia are obligate intracellular parasites of most animal groups including humans, but despite their significant economic and medical importance there are major gaps in our understanding of how they exploit infected host cells. We have investigated the evolution, cellular locations and substrate specificities of a family of nucleotide transport (NTT) proteins from Trachipleistophora hominis, a microsporidian isolated from an HIV/AIDS patient. Transport proteins are critical to microsporidian success because they compensate for the dramatic loss of metabolic pathways that is a hallmark of the group. Our data demonstrate that the use of plasma membrane-located nucleotide transport proteins (NTT) is a key strategy adopted by microsporidians to exploit host cells. Acquisition of an ancestral transporter gene at the base of the microsporidian radiation was followed by lineage-specific events of gene duplication, which in the case of T. hominis has generated four paralogous NTT transporters. All four T. hominis NTT proteins are located predominantly to the plasma membrane of replicating intracellular cells where they can mediate transport at the host-parasite interface. In contrast to published data for Encephalitozoon cuniculi, we found no evidence for the location for any of the T. hominis NTT transporters to its minimal mitochondria (mitosomes), consistent with lineage-specific differences in transporter and mitosome evolution. All of the T. hominis NTTs transported radiolabelled purine nucleotides (ATP, ADP, GTP and GDP) when expressed in Escherichia coli, but did not transport radiolabelled pyrimidine nucleotides. Genome analysis suggests that imported purine nucleotides could be used by T. hominis to make all of the critical purine-based building-blocks for DNA and RNA biosynthesis during parasite intracellular replication, as well as providing essential energy for parasite cellular metabolism and protein synthesis. PMID:25474405

Plasma membrane-located purine nucleotide transport proteins are key components for host exploitation by microsporidian intracellular parasites.

Directory of Open Access Journals (Sweden)

Eva Heinz

2014-12-01

Full Text Available Microsporidia are obligate intracellular parasites of most animal groups including humans, but despite their significant economic and medical importance there are major gaps in our understanding of how they exploit infected host cells. We have investigated the evolution, cellular locations and substrate specificities of a family of nucleotide transport (NTT proteins from Trachipleistophora hominis, a microsporidian isolated from an HIV/AIDS patient. Transport proteins are critical to microsporidian success because they compensate for the dramatic loss of metabolic pathways that is a hallmark of the group. Our data demonstrate that the use of plasma membrane-located nucleotide transport proteins (NTT is a key strategy adopted by microsporidians to exploit host cells. Acquisition of an ancestral transporter gene at the base of the microsporidian radiation was followed by lineage-specific events of gene duplication, which in the case of T. hominis has generated four paralogous NTT transporters. All four T. hominis NTT proteins are located predominantly to the plasma membrane of replicating intracellular cells where they can mediate transport at the host-parasite interface. In contrast to published data for Encephalitozoon cuniculi, we found no evidence for the location for any of the T. hominis NTT transporters to its minimal mitochondria (mitosomes, consistent with lineage-specific differences in transporter and mitosome evolution. All of the T. hominis NTTs transported radiolabelled purine nucleotides (ATP, ADP, GTP and GDP when expressed in Escherichia coli, but did not transport radiolabelled pyrimidine nucleotides. Genome analysis suggests that imported purine nucleotides could be used by T. hominis to make all of the critical purine-based building-blocks for DNA and RNA biosynthesis during parasite intracellular replication, as well as providing essential energy for parasite cellular metabolism and protein synthesis.

Contents and retentions of free and total purine bases in lamb meat cooked by several household methods

Directory of Open Access Journals (Sweden)

P. Anfossi

2011-03-01

Full Text Available Concerns about the content of total and free purine bases in muscle foods and their retentions upon cooking have been since long established (Brulé et al., 1988. Recently, though, an important rôle has been acknowledged to dietary sources of preformed purines for the growth of tissues with a rapid turnover and for optimal function of the cellular immune response, up to the point that the positive features of these nutrients seem to outweigh by far the negative ones (ILSI, 1998. Scanty information exists about the total purine content of raw ovine meat, the only available sources of data being a survey by Herbel and Montag (1987 on purine and pyrimidine contents of protein-rich foods and the comprehensive collection of food composition tables compiled by Scherz and Senser (1994...

TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine] ameliorates diet induced obesity and insulin resistance via inhibition of the IP6K1 pathway.

Science.gov (United States)

Ghoshal, Sarbani; Zhu, Qingzhang; Asteian, Alice; Lin, Hua; Xu, Haifei; Ernst, Glen; Barrow, James C; Xu, Baoji; Cameron, Michael D; Kamenecka, Theodore M; Chakraborty, Anutosh

2016-10-01

Obesity and type 2 diabetes (T2D) lead to various life-threatening diseases such as coronary heart disease, stroke, osteoarthritis, asthma, and neurodegeneration. Therefore, extensive research is ongoing to identify novel pathways that can be targeted in obesity/T2D. Deletion of the inositol pyrophosphate (5-IP7) biosynthetic enzyme, inositol hexakisphosphate kinase-1 (IP6K1), protects mice from high fat diet (HFD) induced obesity (DIO) and insulin resistance. Yet, whether this pathway is a valid pharmacologic target in obesity/T2D is not known. Here, we demonstrate that TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine], a pan-IP6K inhibitor, has strong anti-obesity and anti-diabetic effects in DIO mice. Q-NMR, GTT, ITT, food intake, energy expenditure, QRT-PCR, ELISA, histology, and immunoblot studies were conducted in short (2.5-week)- and long (10-week)-term TNP treated DIO C57/BL6 WT and IP6K1-KO mice, under various diet and temperature conditions. TNP, when injected at the onset of HFD-feeding, decelerates initiation of DIO and insulin resistance. Moreover, TNP facilitates weight loss and restores metabolic parameters, when given to DIO mice. However, TNP does not reduce weight gain in HFD-fed IP6K1-KO mice. TNP specifically enhances insulin sensitivity in DIO mice via Akt activation. TNP decelerates weight gain primarily by enhancing thermogenic energy expenditure in the adipose tissue. Accordingly, TNP's effect on body weight is partly abolished whereas its impact on glucose homeostasis is preserved at thermoneutral temperature. Pharmacologic inhibition of the inositol pyrophosphate pathway has strong therapeutic potential in obesity, T2D, and other metabolic diseases.

One-electron oxidation reactions of purine and pyrimidine bases in cellular DNA.

Science.gov (United States)

Cadet, Jean; Wagner, J Richard; Shafirovich, Vladimir; Geacintov, Nicholas E

2014-06-01

The aim of this survey is to critically review the available information on one-electron oxidation reactions of nucleobases in cellular DNA with emphasis on damage induced through the transient generation of purine and pyrimidine radical cations. Since the indirect effect of ionizing radiation mediated by hydroxyl radical is predominant in cells, efforts have been made to selectively ionize bases using suitable one-electron oxidants that consist among others of high intensity UVC laser pulses. Thus, the main oxidation product in cellular DNA was found to be 8-oxo-7,8-dihydroguanine as a result of direct bi-photonic ionization of guanine bases and indirect formation of guanine radical cations through hole transfer reactions from other base radical cations. The formation of 8-oxo-7,8-dihydroguanine and other purine and pyrimidine degradation products was rationalized in terms of the initial generation of related radical cations followed by either hydration or deprotonation reactions in agreement with mechanistic pathways inferred from detailed mechanistic studies. The guanine radical cation has been shown to be implicated in three other nucleophilic additions that give rise to DNA-protein and DNA-DNA cross-links in model systems. Evidence was recently provided for the occurrence of these three reactions in cellular DNA. There is growing evidence that one-electron oxidation reactions of nucleobases whose mechanisms have been characterized in model studies involving aqueous solutions take place in a similar way in cells. It may also be pointed out that the above cross-linked lesions are only produced from the guanine radical cation and may be considered as diagnostic products of the direct effect of ionizing radiation.

Measurement and application of purine derivatives: Creatinine ratio in spot urine samples of ruminants

International Nuclear Information System (INIS)

Chen, X.B.; Jayasuriya, M.C.N.; Makkar, H.P.S.

2004-01-01

The daily excretion of purine derivatives in urine has been used to estimate the supply of microbial protein to ruminant animals. The method provides a simple and non-invasive tool to indicate the nutritional status of farm animals. However due to the need for complete collection of urine the potential application at farm level is restricted. Research conducted under the FAO/IAEA Co-ordinated Research Project has indicated that it is possible to use the purine derivatives:creatinine ratio measured in several spot urine samples collected within a day, as an index of microbial protein supply in a banding system for farm application. Some theoretical and experimental aspects in the measurement of purine derivatives:creatinine ratio in spot urine samples and the possible application of the banding system at the farm level are discussed. (author)

Characterization of a depurinated-DNA purine-base-insertion activity from Drosophila.

Science.gov (United States)

Deutsch, W A; Spiering, A L

1985-01-01

An activity that binds preferentially to depurinated DNA and inserts purines into those sites was partially purified from Drosophila melanogaster embryos. The protein has a sedimentation coefficient of 4.9 S and is devoid of AP (apurinic/apyrimidinic) endonuclease activity. Upon incorporation of purines into apurinic DNA, the number of alkali-labile sites decreases, thus establishing the conversion of depurinated sites into normal nucleotides. The activity requires K+, and is totally inhibited by caffeine or EDTA. Guanine is specifically incorporated into partially depurinated poly(dG-dC) and adenine is specifically incorporated into poly(dA-dT), thus demonstrating the apparent template specificity of the enzyme. PMID:2417589

Effects of caffeine on purine metabolism and ultraviolet light-induced lethality in cultured mammalian cells

International Nuclear Information System (INIS)

Waldren, C.A.; Patterson, D.

1979-01-01

Caffeine, at doses which enhance the killing action of ultraviolet light, inhibits both de novo synthesis and the utilization of exogenous purines in cultured CHO-K1, a Chinese hamster ovary cell line. The effect is dose dependent, with a caffeine concentration of 7.5 mM producing a 90% reduction in 15 min. Interference with utilization of exogenous purines was seen as a substantial decrease in the conversion of [14C]hypoxanthine, [14C]adenine, or [14C]guanine into their respective di- and triphosphates in the presence of caffeine. Thus, one of the ways by which antimetabolites and caffeine act to enhance ultraviolet light killing may be by interference with the supply of purine nucleotides needed for repair

Synthesis of (purin-6-yl)acetates and 6-(2-hydroxyethyl)purines via cross-couplings of 6-chloropurines with the Reformatsky reagent

Czech Academy of Sciences Publication Activity Database

Hasník, Zbyněk; Šilhár, Peter; Hocek, Michal

2007-01-01

Roč. 48, č. 32 (2007), s. 5589-5592 ISSN 0040-4039 R&D Projects: GA MŠk 1M0508; GA AV ČR 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * nucleosides * cross-coupling reactions Subject RIV: CC - Organic Chemistry Impact factor: 2.615, year: 2007

Effects of pH, temperature, and chemical structure on the stability of S-(purin-6-yl)-L-cysteine: evidence for a novel molecular rearrangement mechanism to yield N-(purin-6-yl)-L-cysteine.

Science.gov (United States)

Elfarra, A A; Hwang, I Y

1996-01-01

The stability of S-(purin-6-yl)-L-cysteine (SPC), a kidney-selective prodrug of 6-mercaptopurine and a putative metabolite of 6-chloropurine, was investigated under various pH and temperature conditions. At room temperature, the half-life (t 1/2) of SPC at either highly acidic (pH 3.6) or basic conditions (pH 9.6) was longer than at neutral or slightly acidic or basic conditions (pH 5.7-8.75). The primary degradation product, N-(purin-6-yl)-L-cysteine (NPC), was isolated using Sephadex LH-20 chromatography and characterized by 1H NMR and FAB/MS after derivatization with 2-iodoacetic acid. These results reveal novel stability requirements and implicate the cysteinyl amino group and the purinyl N-1 nitrogen in the mechanism of SPC rearrangement to NPC. Further evidence for this hypothesis was provided by the findings that the stability of SPC in phosphate buffer (pH 7.4) at 37 degrees C was similar to that of S-(guanin-6-yl)-L-cysteine, whereas S-(purin-6-yl)-N-acetyl-L-cysteine and S-(purin-6-yl)glutathione which have their cysteine amino groups blocked were much more stable than SPC. S-(Purin-6-yl)-L-homocysteine (SPHC) was also more stable than SPC, possibly because the formation of a 6-membered ring transition state as would be expected with SPHC is kinetically less favored than the formation of a 5-membered ring transition state as would be expected with SPC. These results may explain previous in vivo metabolism results of SPC and its analogs and may contribute to a better understanding of stability of structurally related cysteine S-conjugates.

National plan for the radioactive and recyclable wastes management of the national inventory of the radioactive and recyclable wastes to an account and a prospective outlook of the pathways of long dated management of radioactive wastes in France

International Nuclear Information System (INIS)

2005-07-01

The introduction recalls the context of the development of the national plan of radioactive and recyclable wastes management (PNGDR-MV), its objectives and its position in the today studies on radioactive wastes. The first part is devoted to the description of existing radioactive wastes management solutions, or engaged by today activities. The second part concerns the radioactive materials of the nuclear industry, which are not considered as wastes, but which can be recyclable because of their high energy potential as fuels for reactors of the future. The third part examines the pathways coherence. The last part is a synthesis of the evaluation, with more attention on the identifies problems. (A.L.B.)

Myo1c regulates lipid raft recycling to control cell spreading, migration and Salmonella invasion.

Science.gov (United States)

Brandstaetter, Hemma; Kendrick-Jones, John; Buss, Folma

2012-04-15

A balance between endocytosis and membrane recycling regulates the composition and dynamics of the plasma membrane. Internalization and recycling of cholesterol- and sphingolipid-enriched lipid rafts is an actin-dependent process that is mediated by a specialized Arf6-dependent recycling pathway. Here, we identify myosin1c (Myo1c) as the first motor protein that drives the formation of recycling tubules emanating from the perinuclear recycling compartment. We demonstrate that the single-headed Myo1c is a lipid-raft-associated motor protein that is specifically involved in recycling of lipid-raft-associated glycosylphosphatidylinositol (GPI)-linked cargo proteins and their delivery to the cell surface. Whereas Myo1c overexpression increases the levels of these raft proteins at the cell surface, in cells depleted of Myo1c function through RNA interference or overexpression of a dominant-negative mutant, these tubular transport carriers of the recycling pathway are lost and GPI-linked raft markers are trapped in the perinuclear recycling compartment. Intriguingly, Myo1c only selectively promotes delivery of lipid raft membranes back to the cell surface and is not required for recycling of cargo, such as the transferrin receptor, which is mediated by parallel pathways. The profound defect in lipid raft trafficking in Myo1c-knockdown cells has a dramatic impact on cell spreading, cell migration and cholesterol-dependent Salmonella invasion; processes that require lipid raft transport to the cell surface to deliver signaling components and the extra membrane essential for cell surface expansion and remodeling. Thus, Myo1c plays a crucial role in the recycling of lipid raft membrane and proteins that regulate plasma membrane plasticity, cell motility and pathogen entry.

Recycling retention functions

International Nuclear Information System (INIS)

Skrable, K.W.; Chabot, G.E.; Johnson, M.H.

1981-01-01

Beginning with the concept of any number of physiologically meaningful compartments that recycle material with a central extracellular fluid compartment and considering various excretion pathways, we solve the differential equations describing the kinetics by the method of Laplace to obtain concise algebraic expressions for the retentions. These expressions contain both fundamental and eigenvalue rate constants; the eigenvalue rate constants are obtained from the solution of a polynomial incorporating the fundamental rate constants. Mathematically exact expressions that predict the biodistribution resulting from continuous uptakes are used to obtain very simple mathematically exact steady state expressions as well as approximate expressions applicable to any time. These steady state and approximate expressions contain only the fundamental rate constants; also, they include a recycling factor that describes the increase in the biodistributions because of recycling. To obtain the values of the fundamental rate constants, short term kinetics studies along with data on the long term distributions are suggested. Retention functions obtained in this way predict both the short term and long term distributions; they therefore are useful in the interpretation of bioassay data and in the estimation of internal doses

Synthesis of (Purin-6-yl)methylphosphonate Bases and Nucleosides

Czech Academy of Sciences Publication Activity Database

Hasník, Zbyněk; Pohl, Radek; Hocek, Michal

2010-01-01

Roč. 51, č. 18 (2010), s. 2464-2466 ISSN 0040-4039 R&D Projects: GA MŠk 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * nucleosides * phosphonates * cross-coupling Subject RIV: CC - Organic Chemistry Impact factor: 2.618, year: 2010

Efecto Antagónico in vitro de Actinomicetos Aislados de Purines de Chipaca (Bidens pilosa L. Frente a Phytophthora infestans (Mont de Bary In vitro Antagonistic Effect of Actinomycetes Isolated from Chipaca (Bidens pilosa L. Purins Against Phytophthora infestans (Mont de Bary

Directory of Open Access Journals (Sweden)

Yudy Astrid Fonseca Ardila

2011-12-01

Full Text Available Se estudió el efecto inhibidor de los actinomicetos presentes en purines o extractos fermentados de plantas de chipaca (Bidens pilosa L., sobre el crecimiento de Phytophthora infestans (Mont de Bary, causante del tizón tardío de la papa. Se elaboraron cuatro purines de flores, raíces, hojas-tallos y su mezcla. De estos purines se obtuvieron 25 aislamientos de actinomicetos, cada uno de los cuales se enfrentó con P. infestans en placas de medio de cultivo, utilizando la técnica de anillos de Gauze y estableciendo las concentraciones iniciales de esporas mediante conteos microscópicos en cámara de Neubauer. Los actinomicetos no crecieron en el purin de flores debido, posiblemente, a que en él no se utiliza suelo rizosférico o porque su pH (9 es mayor que el rango normal de crecimiento de estos microorganismos ( pH 6 -; 8. Se evidenció inhibición del crecimiento del oomycete por parte de 8 aislamientos de actinomicetos con porcentajes de inhibición entre 33,3 - 77,8%, provenientes de los purines de raíces, tallos-hojas y mezcla de partes de la planta. La mayor inhibición se obtuvo en los aislamientos AC001, AC010, AC011 y AC025 con conteos de 0,4, 6,0, 3,0, y 3,6 x10(5 esporas mL-1.Purins or liquid fermented extracts of chipaca (Bidens pilosa L. were prepared to establish the inhibitory effect of the actinomycetes found in such biopharmaceutical preparations on the growth of Phytophthora infestans (Mont de Bary, the causative of potato late blight disease. Four purins made from flowers, roots, leaf-steams and a mixture of them were prepared; 25 actinomycete isolates were obtained from these purins and their ability to resist challenge by P. infestans was ascertained in medium plates using the ring Gauze technique and establishing initial concentrations of spores by microscopic counting in Neubauer chamber. Actinomycetes did not grow in flower purin as rhizosphere soil was not used in its preparation or because this particular pH (9

Synthesis and Cytotoxic Activity of Some New 2,6-Substituted Purines

Directory of Open Access Journals (Sweden)

Nageswara Rao Kode

2011-07-01

Full Text Available A seriesof twenty four acyclic unsaturated 2,6-substututed purines 5a-20b were synthesized. These compounds were evaluated for cytotoxic activity against NCI-60 DTP human tumor cell line screen at 10µMconcentration. N9-[(Z-4'-chloro-2'-butenyl-1'-yl]-2,6-dichloropurine(5a, N9-[4'-chloro-2'-butynyl-1'-yl]-2,6-dichloropurine(10a, N9-[(E-2',3'-dibromo-4'-chloro-2'-butenyl-1'-yl]-6-methoxypurine(14and N9-[4'-chloro-2'-butynyl-1'-yl]-6-(4-methoxyphenyl-purine(19exhibited highly potent cytotoxic activity with GI50 values in the 1–5 µM range for most human tumor cell lines. Other compounds exhibited moderate activity.

Three-dimensional structure of E. Coli purine nucleoside phosphorylase at 0.99 Å resolution

Energy Technology Data Exchange (ETDEWEB)

Timofeev, V. I., E-mail: tostars@mail.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Abramchik, Yu. A., E-mail: ugama@yandex.ru [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Zhukhlistova, N. E., E-mail: inna@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Muravieva, T. I.; Esipov, R. S. [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2016-03-15

Purine nucleoside phosphorylases (PNPs) catalyze the reversible phosphorolysis of nucleosides and are key enzymes involved in nucleotide metabolism. They are essential for normal cell function and can catalyze the transglycosylation. Crystals of E. coli PNP were grown in microgravity by the capillary counterdiffusion method through a gel layer. The three-dimensional structure of the enzyme was determined by the molecular-replacement method at 0.99 Å resolution. The structural features are considered, and the structure of E. coli PNP is compared with the structures of the free enzyme and its complexes with purine base derivatives established earlier. A comparison of the environment of the purine base in the complex of PNP with formycin A and of the pyrimidine base in the complex of uridine phosphorylase with thymidine revealed the main structural features of the base-binding sites. Coordinates of the atomic model determined with high accuracy were deposited in the Protein Data Bank (PDB-ID: 4RJ2).

Excretion of purine base derivatives after intake of bacterial protein meal in pigs

DEFF Research Database (Denmark)

Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, A.

2007-01-01

Bacterial protein meal has a high content ofprotein but also of RNA and DNA. Sixteen barrows were allocated to four diets containing increasing levels of bacterial protein meal (BPM), from weaning to 80 kg live weight, to evaluate whether the RNA and DNA contents of BPM influenced the retention...... of nitrogen. It was hypothesised that an increased intake of RNA and DNA would lead to an increased urinary excretion of purine base derivatives and increased plasma concentrations. Retention of nitrogen was unaffected by dietary content of BPM (P=0.08) and the urinary excretion of purine base derivatives...

The hormonal regulation of purine biosynthesis: control of the inosinic acid branch point

International Nuclear Information System (INIS)

Pizzichini, M.; Di Stefano, A.; Marinello, E.; Pompucci, G.

1986-01-01

This paper studies the behavior of purine biosynthesis de novo in the levator animal muscle (LAM) of adult rats, before, after castration, and after testosterone administration. The incorporation of C 14-formate into the acid-soluble bases was performed as an index of the overall rate of purine nucleotide synthesis. It is shown that castration reduces the content, the specific activity of total bases and of the single bases in the LAM, indicating an inferior turnover. The increased turnover of guanylic acid, which is always present although not as much as adenylic acid, will favor the sunthesis of RNA in the sexual organs

Stacking of purines in water: the role of dipolar interactions in caffeine.

Science.gov (United States)

Tavagnacco, L; Di Fonzo, S; D'Amico, F; Masciovecchio, C; Brady, J W; Cesàro, A

2016-05-11

During the last few decades it has been ascertained that base stacking is one of the major contributions stabilizing nucleic acid conformations. However, the understanding of the nature of the interactions involved in the stacking process remains under debate and it is a subject of theoretical and experimental studies. Structural similarity between purine bases (guanine and adenine) in DNA and the caffeine molecule makes caffeine an excellent model for the purine bases. The present study clearly shows that dipolar interactions play a fundamental role in determining stacking of purine molecules in solution. In order to reach this achievement, polarized ultraviolet Raman resonant scattering experiments have been carried out on caffeine aqueous solutions as a function of concentration and temperature. The investigation pointed out at the aggregation and solvation properties, particularly at elevated temperatures. Kubo-Anderson theory was used as a framework to investigate the non-coincidence effect (NCE) occurring in the totally symmetric breathing modes of the purine rings, and in the bending modes of the methyl groups of caffeine. The NCE concentration dependence shows that caffeine aggregation at 80 °C occurs by planar stacking of the hydrophobic faces. The data clearly indicate that dipolar interactions determine the reorientational motion of the molecules in solution and are the driving force for the stacking of caffeine. In parallel, the observed dephasing times imply a change in caffeine interactions as a function of temperature and concentration. A decrease, at low water content, of the dephasing time for the ring breathing vibration mode indicates that self-association alters the solvation structure that is detectable at low concentration. These results are in agreement with simulation predictions and serve as an important validation of the models used in those calculations.

A novel approach to select differential pathways associated with hypertrophic cardiomyopathy based on gene co‑expression analysis.

Science.gov (United States)

Chen, Xiao-Min; Feng, Ming-Jun; Shen, Cai-Jie; He, Bin; Du, Xian-Feng; Yu, Yi-Bo; Liu, Jing; Chu, Hui-Min

2017-07-01

The present study was designed to develop a novel method for identifying significant pathways associated with human hypertrophic cardiomyopathy (HCM), based on gene co‑expression analysis. The microarray dataset associated with HCM (E‑GEOD‑36961) was obtained from the European Molecular Biology Laboratory‑European Bioinformatics Institute database. Informative pathways were selected based on the Reactome pathway database and screening treatments. An empirical Bayes method was utilized to construct co‑expression networks for informative pathways, and a weight value was assigned to each pathway. Differential pathways were extracted based on weight threshold, which was calculated using a random model. In order to assess whether the co‑expression method was feasible, it was compared with traditional pathway enrichment analysis of differentially expressed genes, which were identified using the significance analysis of microarrays package. A total of 1,074 informative pathways were screened out for subsequent investigations and their weight values were also obtained. According to the threshold of weight value of 0.01057, 447 differential pathways, including folding of actin by chaperonin containing T‑complex protein 1 (CCT)/T‑complex protein 1 ring complex (TRiC), purine ribonucleoside monophosphate biosynthesis and ubiquinol biosynthesis, were obtained. Compared with traditional pathway enrichment analysis, the number of pathways obtained from the co‑expression approach was increased. The results of the present study demonstrated that this method may be useful to predict marker pathways for HCM. The pathways of folding of actin by CCT/TRiC and purine ribonucleoside monophosphate biosynthesis may provide evidence of the underlying molecular mechanisms of HCM, and offer novel therapeutic directions for HCM.

Estimation of microbial protein supply in ruminants using urinary purine derivatives

International Nuclear Information System (INIS)

Makkar, H.P.S.; Chen, X.B.

2004-01-01

This publication presents various models, describing the quantitative excretion of purine derivatives in urine, developed for various breeds of cattle and for sheep, goat, camel and buffalo and their use for estimation of microbial protein supply in ruminant livestock. It also describes progress made over the last decade in analytical methods for determining purine derivatives, and a unique approach for estimating microbial protein supply using spot urine samples developed under the FAO/IAEA CRP. This approach of using spot urine samples dispenses with quantitative recovery of urine, enabling its use by field and extension workers for evaluation of the nutritional status of farm animals. Future areas of research are also highlighted in the book. This book is a good source of reference for research workers, students and extension workers alike

Purine derivative excretion and microbial protein synthesis in sheep ...

African Journals Online (AJOL)

In a 3 x 3 Latin square design experiment, urinary excretions of purine derivatives (allantoin N, Uric acid N, Xanthine + Hypoxanthine N) were measured and used to estimate microbial N yield in 9 sheep fed roughage- based diet supplemented with 0, 150 and 300g DM grass silage respectively. Daily urinary excretions of ...

Childhood Lead Exposure from Battery Recycling in Vietnam.

Science.gov (United States)

Daniell, William E; Van Tung, Lo; Wallace, Ryan M; Havens, Deborah J; Karr, Catherine J; Bich Diep, Nguyen; Croteau, Gerry A; Beaudet, Nancy J; Duy Bao, Nguyen

2015-01-01

Battery recycling facilities in developing countries can cause community lead exposure. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results.

Purine analogs as phosphatidylinositol 4-kinase III beta inhibitors

Czech Academy of Sciences Publication Activity Database

Šála, Michal; Kögler, Martin; Plačková, Pavla; Mejdrová, Ivana; Hřebabecký, Hubert; Procházková, Eliška; Strunin, Dmytro; Lee, G.; Birkuš, G.; Weber, Jan; Mertlíková-Kaiserová, Helena; Nencka, Radim

2016-01-01

Roč. 26, č. 11 (2016), s. 2706-2712 ISSN 0960-894X R&D Projects: GA ČR GA15-09310S; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : phosphatidylinositol 4-kinase * purine * PI4K III beta * antiviral agent * hepatitis C virus Subject RIV: CC - Organic Chemistry Impact factor: 2.454, year: 2016

Yersinia pestis Targets the Host Endosome Recycling Pathway during the Biogenesis of the Yersinia-Containing Vacuole To Avoid Killing by Macrophages

Science.gov (United States)

Connor, Michael G.; Pulsifer, Amanda R.; Ceresa, Brian K.

2018-01-01

ABSTRACT Yersinia pestis has evolved many strategies to evade the innate immune system. One of these strategies is the ability to survive within macrophages. Upon phagocytosis, Y. pestis prevents phagolysosome maturation and establishes a modified compartment termed the Yersinia-containing vacuole (YCV). Y. pestis actively inhibits the acidification of this compartment, and eventually, the YCV transitions from a tight-fitting vacuole into a spacious replicative vacuole. The mechanisms to generate the YCV have not been defined. However, we hypothesized that YCV biogenesis requires Y. pestis interactions with specific host factors to subvert normal vesicular trafficking. In order to identify these factors, we performed a genome-wide RNA interference (RNAi) screen to identify host factors required for Y. pestis survival in macrophages. This screen revealed that 71 host proteins are required for intracellular survival of Y. pestis. Of particular interest was the enrichment for genes involved in endosome recycling. Moreover, we demonstrated that Y. pestis actively recruits Rab4a and Rab11b to the YCV in a type three secretion system-independent manner, indicating remodeling of the YCV by Y. pestis to resemble a recycling endosome. While recruitment of Rab4a was necessary to inhibit YCV acidification and lysosomal fusion early during infection, Rab11b appeared to contribute to later stages of YCV biogenesis. We also discovered that Y. pestis disrupts global host endocytic recycling in macrophages, possibly through sequestration of Rab11b, and this process is required for bacterial replication. These data provide the first evidence that Y. pestis targets the host endocytic recycling pathway to avoid phagolysosomal maturation and generate the YCV. PMID:29463656

Growth in rice cells requires de novo purine biosynthesis by the blast fungus Magnaporthe oryzae

Science.gov (United States)

Fernandez, Jessie; Yang, Kuan Ting; Cornwell, Kathryn M.; Wright, Janet D.; Wilson, Richard A.

2013-01-01

Increasing incidences of human disease, crop destruction and ecosystem perturbations are attributable to fungi and threaten socioeconomic progress and food security on a global scale. The blast fungus Magnaporthe oryzae is the most devastating pathogen of cultivated rice, but its metabolic requirements in the host are unclear. Here we report that a purine-requiring mutant of M. oryzae could develop functional appressoria, penetrate host cells and undergo the morphogenetic transition to elaborate bulbous invasive hyphae from primary hyphae, but further in planta growth was aborted. Invasive hyphal growth following rice cell ingress is thus dependent on de novo purine biosynthesis by the pathogen and, moreover, plant sources of purines are neither available to the mutant nor required by the wild type during the early biotrophic phase of infection. This work provides new knowledge about the metabolic interface between fungus and host that might be applicable to other important intracellular fungal pathogens. PMID:23928947

The Formation of Nucleobases from the Ultraviolet Photoirradiation of Purine in Simple Astrophysical Ice Analogues.

Science.gov (United States)

Materese, Christopher K; Nuevo, Michel; Sandford, Scott A

2017-08-01

Nucleobases are the informational subunits of RNA and DNA and are essential to all known forms of life. The nucleobases can be divided into two groups of molecules: the pyrimidine-based compounds that include uracil, cytosine, and thymine, and the purine-based compounds that include adenine and guanine. Previous work in our laboratory has demonstrated that uracil, cytosine, thymine, and other nonbiological, less common nucleobases can form abiotically from the UV photoirradiation of pyrimidine in simple astrophysical ice analogues containing combinations of H 2 O, NH 3 , and CH 4 . In this work, we focused on the UV photoirradiation of purine mixed with combinations of H 2 O and NH 3 ices to determine whether or not the full complement of biological nucleobases can be formed abiotically under astrophysical conditions. Room-temperature analyses of the resulting photoproducts resulted in the detection of adenine, guanine, and numerous other functionalized purine derivatives. Key Words: Pyrimidine-Nucleobases-Interstellar; Ices-Cometary; Ices-Molecular processes-Prebiotic chemistry. Astrobiology 17, 761-770.

Effect of tempe waste on excreation of purine derivatives and microbial–N supply in lactating Etawah crossbred goats

Directory of Open Access Journals (Sweden)

D.A Astuti

2002-10-01

Full Text Available The aim of this study was to evaluate excretion of purine derivatives and microbial–N supply in lactating Etawah crossbred goats fed with fermented soybean waste. Sixteen first lactating goats were randomly allotted into four dietary treatment groups that received 50% king grass plus R1: 50% concentrate, R2: 25% concentrate and 25% fresh tempe waste, R3: 25% concentrate and 25% fermented tempe waste, and R4: 25% concentrate and 25% gelatinizing of liquid tempe waste. Fermented tempe waste was made by fermentation of tempe waste (seed content of soybean using Aspergillus niger, while for the gellatinizing of liquid tempe waste was made by gelatinized with maize flour. Protein balance studies were conducted during two week trial and at the end of the research. Urinary protein and purine derivatives were collected for analysis. Microbial–N supply was calculated from purine derivatives excretion. Results showed that nitrogen consumptions were significantly different between R4 and three other treatments and apparent digestible nitrogen in R3 were higher than that of R4 (P<0.05. The nitrogen retention in R1 and R3 were higher than that of R2 and R4. Urinary purine derivatives in this study showed that allantoin, xanthine and hypoxanthine in R3 were higher than that of R4, while R1 and R2 were the same and the highest uric acid excretion and total purine derivatives were observed in R3. Microbial–N supply were significantly different between all treatments where R3 was the highest. This research concluded that fermented soybean waste had the highest total purine derivatives excretion and microbial–N supply to the lactating Etawah crossbred goats.

Urinary excretion of purine derivatives as an index of microbial protein synthesis in the camel (Camelus dromedarius).

Science.gov (United States)

Guerouali, Abdelhai; El Gass, Youssef; Balcells, Joaquim; Belenguer, Alvaro; Nolan, John

2004-08-01

Five experiments were carried out to extend knowledge of purine metabolism in the camel (Camelus dromedarius) and to establish a model to enable microbial protein outflow from the forestomachs to be estimated from the urinary excretion of purine derivatives (PD; i.e. xanthine, hypoxanthine, uric acid, allantoin). In experiment 1, four camels were fasted for five consecutive days to enable endogenous PD excretion in urine to be determined. Total PD excretion decreased during the fasting period to 267 (SE 41.5) micromol/kg body weight (W)0.75 per d. Allantoin and xanthine + hypoxanthine were consistently 86 and 6.1 % of total urinary PD during this period but uric acid increased from 3.6 % to 7.4 %. Xanthine oxidase activity in tissues (experiment 2) was (micromol/min per g fresh tissue) 0.038 in liver and 0.005 in gut mucosa but was not detected in plasma. In experiment 3, the duodenal supply of yeast containing exogenous purines produced a linear increase in urinary PD excretion rate with the slope indicating that 0.63 was excreted in urine. After taking account of endogenous PD excretion, the relationship can be used to predict purine outflow from the rumen. From the latter prediction, and also the purine:protein ratio in bacteria determined in experiment 5, we predicted the net microbial outflow from the rumen. In experiment 4, with increasing food intake, the rate of PD excretion in the urine increased linearly by about 11.1 mmol PD/kg digestible organic matter intake (DOMI), equivalent to 95 g microbial protein/kg DOMI.

Effect of physiological status on endogenous excretion of purine derivatives in cattle

International Nuclear Information System (INIS)

Balcells, J.; Vicente, F.; Orellana-Boero, P.; Martin-Orue, S.; Gonzalez-Ronquillo, M.

2004-01-01

The present study examined the endogenous urinary excretion of purine derivatives (PD: allantoin and uric acid) in normally fed animals in different physiological states. Animals fitted with a simple rumen cannula and a T-shaped duodenal cannula were used in three separate experiments. In Experiment I, three heifers (about 8 months old; 225 ± 4.4 kg) fed a cereal based diet were used. In Experiment 11, two Friesian dry cows (about 24 months old; 696 ± 21 kg) fed at maintenance level on chopped barley straw and barley grain (50:50). In Experiment 3, three multiparous crossbreed Holstein-Friesian cows (560 ± 10 kg, average milk yield 25 ± 3.2 kg/d) in their third lactation were used. The cows were fed a mixed diet (48:52; roughage:concentrate). 15 N ammonium phosphate was infused continuously into the rumen to label microbial purine bases (PB). Duodenal flow of digesta and PB was determined using a dual marker system. After 72-80 h purine enrichment had reached plateau values in body pools and in urine. Daily endogenous PD excretion (μmol/W 0.75 ) obtained in dry cows (310 ± 31.0) were not significantly different from that obtained in growing steers (236 ± 6.0) but were consistently higher (512.4 ± 36.4) in lactating cows. (author)

Childhood Lead Exposure from Battery Recycling in Vietnam

Directory of Open Access Journals (Sweden)

William E. Daniell

2015-01-01

Full Text Available Background. Battery recycling facilities in developing countries can cause community lead exposure. Objective. To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. Methods. This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 μg/dL were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. Results. All children had high BLLs; 28% had BLL ≥45 μg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. Discussion. In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results.

Caracterización de la microbiota bacteriana presente en biorreactores de microalgas alimentados con purines

OpenAIRE

Prado Carrascal, Ana Isabel

2016-01-01

La producción intensiva ganadera, con una alta concentración de animales estabulados, conlleva la generación de grandes cantidades de residuos semilíquidos o purines, cuyo vertido no controlado puede generar contaminación tanto en los suelos como en las aguas superficiales y subterráneas, lo que provoca importantes problemas ambientales que han obligado a legislar su gestión. El tratamiento de los purines tiene por objetivo básico reducir la materia orgánica y el contenido de nutrientes, lo q...

The effect of cyclophosphamide and gamma irradiation on adenosine deaminase and purine nucleoside phosphorylase in mice

International Nuclear Information System (INIS)

Hosek, B.; Bohaecek, J.; Sikulova, J.

1991-01-01

Changes in ADA and PNP activities in the spleens and thymuses of mice were studied after a single administration of cyclophosphamide and after whole-body gamma irradiation, applied alone or three days after CY application, In the first days after the treatment the enzyme activities were significantly depressed with the exception of ADA in the spleen, where a high elevation in relation to controls was observed. During the regeneration period a pronounced rise of PNP activity in the spleen occurred mainly after a combined application of CY and irradiation. In the thymus the regeneration was manifested by a mild increase of both ADA and PNP activities towards control values. The findings suggest that the expressive changes of ADA and PNP activities, participating in the purine salvage pathway, may, after a cytotoxic treatment, influence the nucleotide pool and DNA synthesis in lymphoid organs

A methodology for estimating potential doses and risks from recycling U.S. Department of Energy radioactive scrap metals

International Nuclear Information System (INIS)

MacKinney, J.A.

1995-01-01

The U.S. Environmental Protection Agency (EPA) is considering writing regulations for the controlled use of materials originating from radioactively contaminated zones which may be recyclable. These materials include metals, such as steel (carbon and stainless), nickel, copper, aluminum and lead, from the decommissioning of federal, and non-federal facilities. To develop criteria for the release of such materials, a risk analysis of all potential exposure pathways should be conducted. These pathways include direct exposure to the recycled material by the public and workers, both individual and collective, as well as numerous other potential exposure pathways in the life of the material. EPA has developed a risk assessment methodology for estimating doses and risks associated with recycling radioactive scrap metals. This methodology was applied to metal belonging to the U.S. Department of Energy. This paper will discuss the draft EPA risk assessment methodology as a tool for estimating doses and risks from recycling. (author)

GGA1 regulates signal-dependent sorting of BACE1 to recycling endosomes, which moderates Aβ production

Science.gov (United States)

Toh, Wei Hong; Chia, Pei Zhi Cheryl; Hossain, Mohammed Iqbal; Gleeson, Paul A.

2018-01-01

The diversion of the membrane-bound β-site amyloid precursor protein–(APP) cleaving enzyme (BACE1) from the endolysosomal pathway to recycling endosomes represents an important transport step in the regulation of amyloid beta (Aβ) production. However, the mechanisms that regulate endosome sorting of BACE1 are poorly understood. Here we assessed the transport of BACE1 from early to recycling endosomes and have identified essential roles for the sorting nexin 4 (SNX4)-mediated, signal-independent pathway and for a novel signal-mediated pathway. The signal-mediated pathway is regulated by the phosphorylation of the DXXLL-motif sequence DISLL in the cytoplasmic tail of BACE1. The phosphomimetic S498D BACE1 mutant was trafficked to recycling endosomes at a faster rate compared with wild-type BACE1 or the nonphosphorylatable S498A mutant. The rapid transit of BACE1 S498D from early endosomes was coupled with reduced levels of amyloid precursor protein processing and Aβ production, compared with the S498A mutant. We show that the adaptor, GGA1, and retromer are essential to mediate rapid trafficking of phosphorylated BACE1 to recycling endosomes. In addition, the BACE1 DISLL motif is phosphorylated and regulates endosomal trafficking, in primary neurons. Therefore, post-translational phosphorylation of DISLL enhances the exit of BACE1 from early endosomes, a pathway mediated by GGA1 and retromer, which is important in regulating Aβ production. PMID:29142073

Estimation of rumen microbial protein production from urinary purine derivatives in zebu cattle and water buffalo

International Nuclear Information System (INIS)

Liang, J.B.; Pimpa, O.; Abdullah, N.; Jelan, Z.A.; Nolan, J.V.

1999-01-01

Two experiments were conducted in order to develop equations for predicting rumen microbial protein production for indigenous Kedah-Kelantan (KK) cattle and swamp buffaloes in Malaysia, using urinary purine derivatives (PD) excretion rates. Endogenous PD excretion rates determined by a fasting procedure for KK cattle and swamp buffalo were 275 and 370 μmol/kg W 0.75 /day, respectively. Urinary PD excretion rate per kg digestible organic matter intake (DOMI) for KK cattle was higher than that for swamp buffalo, reconfirming the earlier findings. Glomerular filtration rate, allantoin and uric acid tubular load and PD re-absorption rate for swamp buffalo were generally higher than those for KK cattle. However, due to the large variations among animals within species, these parameters were not significantly different between species. Nevertheless, the higher PD reabsorption in swamp buffalo provides support for the earlier postulation that the lower urinary PD excretion rate of swamp buffalo was due to their higher recycling of plasma PD as compared to KK cattle. Labelled 8- 14 C uric acid was used to estimate the ratio of renal to non-renal PD excretion. The recovery rates of the radioactive tracer via the renal route for both species were much lower than values reported previously for unlabelled PD for European cattle. (author)

Development of Equation Based on Urinary Purine Derivatives to Estimate Rumen Microbial Protein Production in Goats

International Nuclear Information System (INIS)

Jetana, Thongsuk; Abdullah, Norhani; Liang, Boo Juan; Syed Salim, Syed Jalaludin; Ho, Wan Yin

2003-06-01

Three experiments were conducted at the farm of the Universiti Putra Malaysia, Serdang, Selangor, Malaysia, to establish a model as an index for estimating rumen microbial protein production. In Experiment 1, six Ferral male goats (wt. 40.2±4.6 kg) were used to determine the endogenous purine derivatives (PD) excreted in the urine by fasting. In Experiment 2, four Ferral male goats (wt. 39.6±1.8 kg) were used to measure the proportion of plasma PD excreted in the urine by using [ 14 C]-uric acid as a marker at two levels of feed intake (40% and 80% voluntary intake), using an incomplete 2x4 Latin square experimental design. The feed consisted of 40% oil palm frond and 60% concentrate (OPFC). In Experiment 3, four Ferral male goats fed (OPFC)) were slaughtered and rumen contents were taken for measurements of purine and total nitrogen contents of mixed rumen microbes. The results showed that endogenous PD (allantoin, uric acid, xanthine and hypoxanthine) excreted in the urine obtained by the fasting trial was 202±17 μmol/kg BW 0 . 75 d - 1. The average percentage recovery of plasma PD excretion in the urine by using [ 14 C)-uric acid as a marker was 83±2.0% (cv=6.88, ranged 76.3-91.4%, n=8). Percentage recovery was not affected by levels of feed intake. The ratio of purine N: total N in the mixed rumen liquid associated bacteria (LAB) was 0.085. In this study, a preliminary model for goats was established by using the information from the recovery of labeled PD [ 14 C]-uric acid and the fasting PD excretion. The model obtained was Y 0.83X + 0.202 x BW 0 . 75 , where Y = PD excretion in the urine (mmol/d) X PD absorption at small intestine (mmol/d) BW 0 . 75 = Metabolic body weight (kg) Thus the microbial nitrogen based on total PD (MNpd) can be calculated as follows: MNpd = 70 x X = 0.992 x X (g/d) 0.085 x 0.83 x 1000 where 0.085 is the ratio of purine-N: total N in mixed rumen microbes, 0.83 is the average of digestibility of microbial purine from published

Dual pathways for the intracellular processing of insulin. Relationship between retroendocytosis of intact hormone and the recycling of insulin receptors

International Nuclear Information System (INIS)

Marshall, S.

1985-01-01

Adipocytes process insulin through either of two pathways: a retroendocytotic pathway that culminates in the release of intact insulin, and a degradative pathway that terminates in the intracellular catabolism and release of degraded ligand. Mechanistically, these pathways were found to differ in several ways. First, temporal differences were found in the rate at which intact and degraded products were extruded. After 125 I-insulin was preloaded into the cell interior, intact ligand was completely released during the first 10 min (t 1/2 = 2 min), whereas degraded insulin was released at a much slower rate over 1 h (t 1/2 greater than 8 min). Secondly, it was found that chloroquine profoundly inhibited the insulin degradative pathway, resulting in the intracellular accumulation of intact ligand and a reduction in the release of degraded products. In contrast, however, chloroquine was without effect on the retroendocytotic processing of insulin. Based on the known actions of chloroquine, it appears that retroendocytosis of insulin does not involve vesicular acidification or dissociation of the insulin-receptor complex and that insulin is most likely carried to the cell exterior in the same vesicles (either receptor-bound or free) as those mediating recycling receptors. Interestingly, accumulation of undergraded insulin within chloroquine-treated cells did not result in the release of additional intact ligand, suggesting that once insulin enters the degradative compartment it is committed to catabolism and cannot exit the cell through the retroendocytotic pathway. A third difference was revealed by the finding that extracellular unlabeled insulin (100 ng/ml) markedly accelerated the rate at which preloaded 125 I-insulin was released from adipocytes (t 1/2 of 3 min versus 7 min in controls cells)

Hanford recycling

Energy Technology Data Exchange (ETDEWEB)

Leonard, I.M.

1996-09-01

This paper is a study of the past and present recycling efforts on the Hanford site and options for future improvements in the recycling program. Until 1996, recycling goals were voluntarily set by the waste generators: this year, DOE has imposed goals for all its sites to accomplish by 1999. Hanford is presently meeting the voluntary site goals, but may not be able to meet all the new DOE goals without changes to the program. Most of these new DOE goals are recycling goals: * Reduce the generation of radioactive (low-level) waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of low-level mixed waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of hazardous waste from routine operations 50 percent through source reduction and recycling. * Recycle 33 percent of the sanitary waste from all operations. * Increase affirmative procurement of EPA-designated recycled items to 100 percent. The Hanford recycling program has made great strides-there has been a 98 percent increase in the amount of paper recycled since its inception in 1990. Hanford recycles paper, chemicals cardboard, tires, oil, batteries, rags, lead weights, fluorescent tubes, aerosol products, concrete, office furniture, computer software, drums, toner cartridges, and scrap metal. Many other items are recycled or reused by individual groups on a one time basis without a formal contract. Several contracts are closed-loop contracts which involve all parts of the recycle loop. Considerable savings are generated from recycling, and much more is possible with increased attention and improvements to this program. General methods for improving the recycling program to ensure that the new goals can be met are: a Contract and financial changes 0 Tracking database and methods improvements 0 Expanded recycling efforts. Specifically, the Hanford recycling program would be improved by: 0 Establishing one overall

The methionine salvage pathway in Bacillus subtilis

Directory of Open Access Journals (Sweden)

Danchin Antoine

2002-04-01

Full Text Available Abstract Background Polyamine synthesis produces methylthioadenosine, which has to be disposed of. The cell recycles it into methionine through methylthioribose (MTR. Very little was known about MTR recycling for methionine salvage in Bacillus subtilis. Results Using in silico genome analysis and transposon mutagenesis in B. subtilis we have experimentally uncovered the major steps of the dioxygen-dependent methionine salvage pathway, which, although similar to that found in Klebsiella pneumoniae, recruited for its implementation some entirely different proteins. The promoters of the genes have been identified by primer extension, and gene expression was analyzed by Northern blotting and lacZ reporter gene expression. Among the most remarkable discoveries in this pathway is the role of an analog of ribulose diphosphate carboxylase (Rubisco, the plant enzyme used in the Calvin cycle which recovers carbon dioxide from the atmosphere as a major step in MTR recycling. Conclusions A complete methionine salvage pathway exists in B. subtilis. This pathway is chemically similar to that in K. pneumoniae, but recruited different proteins to this purpose. In particular, a paralogue or Rubisco, MtnW, is used at one of the steps in the pathway. A major observation is that in the absence of MtnW, MTR becomes extremely toxic to the cell, opening an unexpected target for new antimicrobial drugs. In addition to methionine salvage, this pathway protects B. subtilis against dioxygen produced by its natural biotope, the surface of leaves (phylloplane.

TD-DFT investigation of the magnetic circular dichroism spectra of some purine and pyrimidine bases of nucleic acids.

Science.gov (United States)

Fahleson, Tobias; Kauczor, Joanna; Norman, Patrick; Santoro, Fabrizio; Improta, Roberto; Coriani, Sonia

2015-05-28

We present a computational study of the magnetic circular dichroism (MCD) spectra in the 200-300 nm wavelength region of purine and its derivative hypoxanthine, as well as of the pyrimidine bases of nucleic acids uracil, thymine, and cytosine, using the B3LYP and CAM-B3LYP functionals. Solvent effects are investigated within the polarizable continuum model and by inclusion of explicit water molecules. In general, the computed spectra are found to be in good agreement with the experimental ones, apart from some overall blue shifts. Both the pseudo-A term shape of the MCD spectra of the purines and the B term shape of the spectra of pyrimidine bases are reproduced. Our calculations also correctly reproduce the reversed phase of the MCD bands in purine compared to that of its derivatives present in nucleic acids. Solvent effects are sizable and system specific, but they do not in general alter the qualitative shape of the spectra. The bands are dominated by the bright π → π* transitions, and our calculations in solution nicely reproduce their energy differences, improving the estimates obtained in the gas phase. Shoulders are predicted for purine and uracil due to n → π* excitations, but they are too weak to be observed in the experiment.

Effect of training load structure on purine metabolism in middle-distance runners.

Science.gov (United States)

Zieliński, Jacek; Kusy, Krzysztof; Rychlewski, Tadeusz

2011-09-01

There are no studies analyzing the effect of training loads on purine metabolism during long training periods. The study's purpose was to evaluate the effect of training load changes and subsequent detraining on purine metabolism in middle-distance runners during a 1-yr cycle. In four characteristic points of the training cycle, loads assigned to five intensity zones, pre- and postexercise plasma hypoxanthine (Hx) and uric acid, and erythrocyte Hx-guanine phosphoribosyltransferase (HGPRT) activity were determined in 11 male middle-distance runners at the national level, practicing competitive sport for 8.1 ± 0.3 yr and with a mean age of 22.3 ± 0.7 yr, body mass of 73.0 ± 3.4 kg, and body height of 180 ± 2.2 cm. In the competition phase (CP), training loads in aerobic compensation and threshold zones decreased by 65.4% and by 20.5%, respectively. At the same time, anaerobic training loads increased by 132.5% in the VO(2max) zone and by 74.6% in the lactic acid tolerance zone. Postexercise Hx decreased significantly in CP by 6.2 μmol·L(-1). and increased in the transition phase (TP) by 17.4 μmol·L(-1). Both pre- and postexercise HGPRT activity increased significantly in CP by 9.3 nmol·mg(-1)·h(-1). and by 4.9 nmol·mg(-1)·h(-1). , respectively, and decreased significantly in TP by 10.6 nmol·mg(-1)·h(-1). and by 12.0 nmol·mg(-1)·h(-1). , respectively. A significant uric acid increase of 54 μmol·L(-1). was revealed merely in TP. The effect of anaerobic training on purine metabolism is significant despite of a very short total duration of anaerobic loads. Elevated preexercise HGPRT activity in CP suggests adaptation changes consisting in a "permanent readiness" for purine salvage. The detraining in TP leads to reverse adaptation changes. Probably, plasma Hx concentration and erythrocyte HGPRT activity may be considered as a useful measure of training status.

Optimization of the operation of separation of the solids in suspension of the purines (Part I); Optimizacion de la operacion de separacion de los solidos en suspension de los purines (Parte I)

Energy Technology Data Exchange (ETDEWEB)

Bosque Hernandez, J. L. del; Martin Sanchez, J. L.

2004-07-01

The swinish cattle raising you can calculate in our country m 18 million heads. Locating the Spanish cattle cabin in the second position of the European Union. This sector is of great importance in the economy, having big possibilities of growth, due to the great existent demand. However, the generated residuals, denominated purines, they suppose a great obstacle for the expansion of this sector. The purines mammoth production and other cattle residuals outline a serious problem of environmental contamination; for what is necessary to establish the approaches for an appropriate treatment of the same ones, with the purpose of achieving the elimination of the problems of environmental contamination that you/they generate and, in special way, those contamination of the waters. (Author) 5 refs.

Recycling potential of neodymium: the case of computer hard disk drives.

Science.gov (United States)

Sprecher, Benjamin; Kleijn, Rene; Kramer, Gert Jan

2014-08-19

Neodymium, one of the more critically scarce rare earth metals, is often used in sustainable technologies. In this study, we investigate the potential contribution of neodymium recycling to reducing scarcity in supply, with a case study on computer hard disk drives (HDDs). We first review the literature on neodymium production and recycling potential. From this review, we find that recycling of computer HDDs is currently the most feasible pathway toward large-scale recycling of neodymium, even though HDDs do not represent the largest application of neodymium. We then use a combination of dynamic modeling and empirical experiments to conclude that within the application of NdFeB magnets for HDDs, the potential for loop-closing is significant: up to 57% in 2017. However, compared to the total NdFeB production capacity, the recovery potential from HDDs is relatively small (in the 1-3% range). The distributed nature of neodymium poses a significant challenge for recycling of neodymium.

Cell-Autonomous Regulation of Mu-Opioid Receptor Recycling by Substance P

Science.gov (United States)

Bowman, Shanna L.; Soohoo, Amanda L.; Shiwarski, Daniel J.; Schulz, Stefan; Pradhan, Amynah A.; Puthenveedu, Manojkumar A.

2015-01-01

SUMMARY How neurons coordinate and reprogram multiple neurotransmitter signals is an area of broad interest. Here, we show that substance P (SP), a neuropep-tide associated with inflammatory pain, reprograms opioid receptor recycling and signaling. SP, through activation of the neurokinin 1 (NK1R) receptor, increases the post-endocytic recycling of the muopioid receptor (MOR) in trigeminal ganglion (TG) neurons in an agonist-selective manner. SP-mediated protein kinase C (PKC) activation is both required and sufficient for increasing recycling of exogenous and endogenous MOR in TG neurons. The target of this cross-regulation is MOR itself, given that mutation of either of two PKC phosphorylation sites on MOR abolishes the SP-induced increase in recycling and resensitization. Furthermore, SP enhances the resensitization of fentanyl-induced, but not morphine-induced, antinociception in mice. Our results define a physiological pathway that cross-regulates opioid receptor recycling via direct modification of MOR and suggest a mode of homeo-static interaction between the pain and analgesic systems. PMID:25801029

Catalytic carbene transfer allows the direct customization of cyclic purine dinucleotides.

Science.gov (United States)

Fei, Na; Häussinger, Daniel; Blümli, Seraina; Laventie, Benoît-Joseph; Bizzini, Lorenzo D; Zimmermann, Kaspar; Jenal, Urs; Gillingham, Dennis

2014-08-11

We describe a simple method for the direct modification of nucleobases in cyclic purine dinucleotides, important signalling molecules in both prokaryotes and eukaryotes. The method tolerates all members of the cyclic dinucleotide family and could be used to modulate their function or introduce useful side-chains such as fluorophores and photo-crosslinking groups.

Direct determination of tautomerism in purine derivatives by low-temperature NMR spectroscopy

Czech Academy of Sciences Publication Activity Database

Sečkářová, P.; Marek, R.; Maliňáková, K.; Kolehmainen, E.; Hocková, Dana; Hocek, Michal; Sklenář, V.

2004-01-01

Roč. 45, č. 33 (2004), s. 6259-6263 ISSN 0040-4039 R&D Projects: GA MŠk LN00A016 Institutional research plan: CEZ:AV0Z4055905 Keywords : purine * NMR * tautomerism Subject RIV: CC - Organic Chemistry Impact factor: 2.484, year: 2004

Absorption and Intermediary Metabolism of Purines and Pyrimidines in Lactating Dairy Cows

DEFF Research Database (Denmark)

Nielsen, Charlotte Stentoft; Røjen, Betina Amdisen; Jensen, Søren Krogh

2015-01-01

About 20 % of ruminal microbial N in dairy cows derives from purines and pyrimidines; however, their intermediary metabolism and contribution to the overall N metabolism has sparsely been described. In the present study, the postprandial patterns of net portal-drained viscera (PDV) and hepatic...

Efecto antagónico in vitro de actinomicetos aislados de purines de chipaca (bidens pilosa l.) frente a phytophthora infestans (mont) de bary

OpenAIRE

Fonseca Ardila, Yudy Astrid; Castellanos Suárez, Diana Edith; León Sicard, Tomás Enrique

2011-01-01

Se estudió el efecto inhibidor de los actinomicetos presentes en purines o extractos fermentados de plantas de chipaca (Bidens pilosa L.), sobre el crecimiento de Phytophthora infestans (Mont) de Bary, causante del tizón tardío de la papa. Se elaboraron cuatro purines de flores, raíces, hojas-tallos y su mezcla. De estos purines se obtuvieron 25 aislamientos de actinomicetos, cada uno de los cuales se enfrentó con P. infestans en placas de medio de cultivo, utilizando la técnica de anillos de...

Recycling of Gallium from End-of-Life Light Emitting Diodes

Directory of Open Access Journals (Sweden)

Nagy S.

2017-06-01

Full Text Available Nowadays Light Emitting Diodes (LEDs are widely utilized. They are applied as backlighting in Liquid Crystal Displays (LCD and TV sets or as lighting equipments in homes, cars, instruments and street-lightning. End of life equipments are containing more and more LEDs. The recovery of valuable materials – such as Ga, Au, Cu etc. – from the LEDs is essential for the creating the circular economy. First task is the development of a proper recycling technology. Most of the researchers propose fully chemical or thermal-chemical pathway for the recycling of LEDs.

Loss of nitric oxide-mediated inhibition of purine neurotransmitter release in the colon in the absence of interstitial cells of Cajal.

Science.gov (United States)

Durnin, Leonie; Lees, Andrea; Manzoor, Sheerien; Sasse, Kent C; Sanders, Kenton M; Mutafova-Yambolieva, Violeta N

2017-11-01

Regulation of colonic motility depends on the integrity of enteric inhibitory neurotransmission mediated by nitric oxide (NO), purine neurotransmitters, and neuropeptides. Intramuscular interstitial cells of Cajal (ICC-IM) and platelet-derived growth factor receptor-α-positive (PDGFRα + ) cells are involved in generating responses to NO and purine neurotransmitters, respectively. Previous studies have suggested a decreased nitrergic and increased purinergic neurotransmission in Kit W /Kit W-v ( W/W v ) mice that display lesions in ICC-IM along the gastrointestinal tract. However, contributions of NO to these phenotypes have not been evaluated. We used small-chamber superfusion assays and HPLC to measure the spontaneous and electrical field stimulation (EFS)-evoked release of nicotinamide adenine dinucleotide (NAD + )/ADP-ribose, uridine adenosine tetraphosphate (Up4A), adenosine 5'-triphosphate (ATP), and metabolites from the tunica muscularis of human, monkey, and murine colons and circular muscle of monkey colon, and we tested drugs that modulate NO levels or blocked NO receptors. NO inhibited EFS-evoked release of purines in the colon via presynaptic neuromodulation. Colons from W/W v , Nos1 -/- , and Prkg1 -/- mice displayed augmented neural release of purines that was likely due to altered nitrergic neuromodulation. Colons from W/W v mice demonstrated decreased nitrergic and increased purinergic relaxations in response to nerve stimulation. W/W v mouse colons demonstrated reduced Nos1 expression and reduced NO release. Our results suggest that enhanced purinergic neurotransmission may compensate for the loss of nitrergic neurotransmission in muscles with partial loss of ICC. The interactions between nitrergic and purinergic neurotransmission in the colon provide novel insight into the role of neurotransmitters and effector cells in the neural regulation of gastrointestinal motility. NEW & NOTEWORTHY This is the first study investigating the role of nitric

Cross-coupling reactions of unprotected halopurine bases, nucleosides, nucleotides and nucleoside triphosphates with 4-boronophenylalanine in water. Synthesis of (purin-8-yl)- and (purin-6-yl)phenylalanines

Czech Academy of Sciences Publication Activity Database

Čapek, Petr; Pohl, Radek; Hocek, Michal

2006-01-01

Roč. 4, č. 11 (2006), s. 2278-2284 ISSN 1477-0520 R&D Projects: GA AV ČR(CZ) 1QS400550501; GA MŠk(CZ) 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : amino acids * purines * nucleosides * cross-coupling reactions Subject RIV: CC - Organic Chemistry Impact factor: 2.874, year: 2006

Nitrogen K-edge X-ray absorption near edge structure (XANES) spectra of purine-containing nucleotides in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Shimada, Hiroyuki; Fukao, Taishi; Minami, Hirotake; Ukai, Masatoshi [Department of Applied Physics, Tokyo University of Agriculture and Technology, Koganei-shi, Tokyo 184-8588 (Japan); Fujii, Kentaro; Yokoya, Akinari [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Fukuda, Yoshihiro; Saitoh, Yuji [Synchrotron Radiation Research Center, Japan Atomic Energy Agency, Sayo-gun, Hyougo 679-5148 (Japan)

2014-08-07

The N K-edge X-ray absorption near edge structure (XANES) spectra of the purine-containing nucleotide, guanosine 5{sup ′}-monophosphate (GMP), in aqueous solution are measured under various pH conditions. The spectra show characteristic peaks, which originate from resonant excitations of N 1s electrons to π* orbitals inside the guanine moiety of GMP. The relative intensities of these peaks depend on the pH values of the solution. The pH dependence is explained by the core-level shift of N atoms at specific sites caused by protonation and deprotonation. The experimental spectra are compared with theoretical spectra calculated by using density functional theory for GMP and the other purine-containing nucleotides, adenosine 5{sup ′}-monophosphate, and adenosine 5{sup ′}-triphosphate. The N K-edge XANES spectra for all of these nucleotides are classified by the numbers of N atoms with particular chemical bonding characteristics in the purine moiety.

Adaptive evolution to a high purine and fat diet of carnivorans revealed by gut microbiomes and host genomes.

Science.gov (United States)

Zhu, Lifeng; Wu, Qi; Deng, Cao; Zhang, Mengjie; Zhang, Chenglin; Chen, Hua; Lu, Guoqing; Wei, Fuwen

2018-05-01

Carnivorous members of the Carnivora reside at the apex of food chains and consume meat-only diets, rich in purine, fats and protein. Here, we aimed to identify potential adaptive evolutionary signatures compatible with high purine and fat metabolism based on analysis of host genomes and symbiotic gut microbial metagenomes. We found that the gut microbiomes of carnivorous Carnivora (e.g., Felidae, Canidae) clustered in the same clade, and other clades comprised omnivorous and herbivorous Carnivora (e.g., badgers, bears and pandas). The relative proportions of genes encoding enzymes involved in uric acid degradation were higher in the gut microbiomes of meat-eating carnivorans than plant-eating species. Adaptive amino acid substitutions in two enzymes, carnitine O-palmitoyltransferase 1 (CPT1A) and lipase F (LIPF), which play a role in fat digestion, were identified in Felidae-Candidae species. Carnivorous carnivorans appear to endure diets high in purines and fats via gut microbiomic and genomic adaptations. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

Rab14 and its exchange factor FAM116 link endocytic recycling and adherens junction stability in migrating cells.

Science.gov (United States)

Linford, Andrea; Yoshimura, Shin-ichiro; Nunes Bastos, Ricardo; Langemeyer, Lars; Gerondopoulos, Andreas; Rigden, Daniel J; Barr, Francis A

2012-05-15

Rab GTPases define the vesicle trafficking pathways underpinning cell polarization and migration. Here, we find that Rab4, Rab11, and Rab14 and the candidate Rab GDP-GTP exchange factors (GEFs) FAM116A and AVL9 are required for cell migration. Rab14 and its GEF FAM116A localize to and act on an intermediate compartment of the transferrin-recycling pathway prior to Rab11 and after Rab5 and Rab4. This Rab14 intermediate recycling compartment has specific functions in migrating cells discrete from early and recycling endosomes. Rab14-depleted cells show increased N-cadherin levels at junctional complexes and cannot resolve cell-cell junctions. This is due to decreased shedding of cell-surface N-cadherin by the ADAM family protease ADAM10/Kuzbanian. In FAM116A- and Rab14-depleted cells, ADAM10 accumulates in a transferrin-positive endocytic compartment, and the cell-surface level of ADAM10 is correspondingly reduced. FAM116 and Rab14 therefore define an endocytic recycling pathway needed for ADAM protease trafficking and regulation of cell-cell junctions. Copyright © 2012 Elsevier Inc. All rights reserved.

9-Benzyl-6-benzylsulfanyl-9H-purin-2-amine

Directory of Open Access Journals (Sweden)

Maywan Hariono

2014-03-01

Full Text Available In the title compound, C19H17N5S, the dihedral angles between the purine ring system (r.m.s. deviation = 0.009 Å and the S-bound and methylene-bound phenyl rings are 74.67 (8 and 71.28 (7°, respectively. In the crystal, inversion dimers linked by pairs of N—H...N hydrogen bonds generate R22(8 loops. C—H...N interactions link the dimers into (100 sheets.

Increase in urinary purines and pyrimidines in patients with methylmalonic aciduria combined with homocystinuria.

Science.gov (United States)

Porcu, Simona; Corda, Marcella; Lilliu, Franco; Contini, Liliana; Era, Benedetta; Traldi, Pietro; Fais, Antonella

2010-06-03

Methylmalonic aciduria combined with homocystinuria (MMA-HC) is the biochemical trait of a metabolic disorder resulting from impaired conversion of dietary cobalamin (cbl, or vitamin B12) to its two metabolically active forms. Effects on urinary purine and pyrimidine levels have not been described for this condition. Urine samples were collected from three patients with methylmalonic aciduria combined with homocystinuria and from 70 healthy subjects. Urinary purine and pyrimidine levels were quantitated by the use of LC/UV-Vis and LC/ESI/MS. Higher urine levels of pyrimidines were detected with both methods in patients compared to controls. Methylmalonic aciduria with homocystinuria is due to deficiency of the enzyme, cobalamin reductase. The enzyme defect leads to altered hepatic metabolism, which appears to modify circulating pyrimidine levels. Copyright 2010 Elsevier B.V. All rights reserved.

Expanded recycling at Los Alamos National Laboratory

International Nuclear Information System (INIS)

Betschart, J.F.; Malinauskas, L.; Burns, M.

1996-01-01

The Pollution Prevention Program Office has increased recycling activities, reuse, and options to reduce the solid waste streams through streamlining efforts that applied best management practices. The program has prioritized efforts based on volume and economic considerations and has greatly increased Los Alamos National Laboratory's (LANL's) recycle volumes. The Pollution Prevention Program established and chairs a Solid Waste Management Solutions Group to specifically address and solve problems in nonradioactive, Resource Conservation and Recovery Act (RCRA), state-regulated, and sanitary and industrial waste streams (henceforth referred to as sanitary waste in this paper). By identifying materials with recycling potential, identifying best management practices and pathways to return materials for reuse, and introducing the concept and practice of open-quotes asset management,open-quotes the Group will divert much of the current waste stream from disposal. This Group is developing procedures, agreements, and contracts to stage, collect, sort, segregate, transport and process materials, and is also garnering support for the program through the involvement of upper management, facility managers, and generators

Cell-Autonomous Regulation of Mu-Opioid Receptor Recycling by Substance P

Directory of Open Access Journals (Sweden)

Shanna L. Bowman

2015-03-01

Full Text Available How neurons coordinate and reprogram multiple neurotransmitter signals is an area of broad interest. Here, we show that substance P (SP, a neuropeptide associated with inflammatory pain, reprograms opioid receptor recycling and signaling. SP, through activation of the neurokinin 1 (NK1R receptor, increases the post-endocytic recycling of the mu-opioid receptor (MOR in trigeminal ganglion (TG neurons in an agonist-selective manner. SP-mediated protein kinase C (PKC activation is both required and sufficient for increasing recycling of exogenous and endogenous MOR in TG neurons. The target of this cross-regulation is MOR itself, given that mutation of either of two PKC phosphorylation sites on MOR abolishes the SP-induced increase in recycling and resensitization. Furthermore, SP enhances the resensitization of fentanyl-induced, but not morphine-induced, antinociception in mice. Our results define a physiological pathway that cross-regulates opioid receptor recycling via direct modification of MOR and suggest a mode of homeostatic interaction between the pain and analgesic systems.

Recycled wind turbine blades as a feedstock for second generation composites.

Science.gov (United States)

Mamanpush, Seyed Hossein; Li, Hui; Englund, Karl; Tabatabaei, Azadeh Tavousi

2018-06-01

With an increase in renewable wind energy via turbines, an underlying problem of the turbine blade disposal is looming in many areas of the world. These wind turbine blades are predominately a mixture of glass fiber composites (GFCs) and wood and currently have not found an economically viable recycling pathway. This work investigates a series of second generation composites fabricated using recycled wind turbine material and a polyurethane adhesive. The recycled material was first comminuted via a hammer-mill through a range of varying screen sizes, resinated and compressed to a final thickness. The refined particle size, moisture content and resin content were assessed for their influence on the properties of recycled composites. Static bending, internal bond and water sorption properties were obtained for all composites panels. Overall improvement of mechanical properties correlated with increase in resin content, moisture content, and particle size. The current investigation demonstrates that it is feasible and promising to recycle the wind turbine blade to fabricate value-added high-performance composite. Copyright © 2018 Elsevier Ltd. All rights reserved.

Substituent and noncovalent interaction effects in the reactivity of purine derivatives with tetracarboxylato-dirhodium(II) units. Rationalization of a rare binding mode via N3.

Science.gov (United States)

Amo-Ochoa, Pilar; Castillo, Oscar; Harrington, Ross W; Zamora, Félix; Houlton, Andrew

2013-02-18

Reactions between [Rh(2)(CH(3)COO)(4)] with 2,6-diaminopurine (HDap) or 6-chloro-2-aminopurine (HClap) and [Rh(2)((CH(3))(3)CCOO)(4)] with HClap produce, three new dirhodium(II) carboxylate complexes of the general form, [Rh(2)(RCOO)(4)(Purine)(2)] (R = CH(3), (CH(3))(3)C). Single crystal X-ray diffraction studies confirm that in all cases the purine coordinates to the axial position of the dirhodium(II)tetracarboxylate unit. However, while the complex obtained with HDap features the typical purine binding mode via N(7), complexes containing HClap show unusual N3 coordination. This is an extremely rare instance of an unrestricted purine binding via N3. Some rationalization of these data is offered based on a series of DFT calculations.

The purine efflux pump PbuE in Bacillus subtilis modulates expression of the PurR and G-box (XptR) regulons by adjusting the purine base pool size

DEFF Research Database (Denmark)

Nygaard, P.; Saxild, Hans Henrik

2005-01-01

a functional PbuE pump. In a mutant defective in the metabolism of adenine, the ade apt mutant, we found a high intracellular level of adenine and constitutive high levels of PbuE. A growth test using a purine auxotroph provided further evidence for the role of PbuE in lowering the intracellular concentration...

A review of metabolism of labeled glucoses for use in measuring glucose recycling

International Nuclear Information System (INIS)

Russell, R.W.; Young, J.W.

1990-01-01

The fate of tritium from each carbon of D-glucose and the metabolism of L-glucose and 2-deoxy-D-glucose are known. Differences in metabolism of labeled glucoses can be used to quantify physical and chemical recycling of glucose. Only physical recycling is measured by [1- 3 H]-L-glucose, whereas [U- 14 C]-D-glucose measures total recycling. The difference between [1- 3 H]-L-glucose and [U- 14 C]-D-glucose, therefore, is chemical recycling. Recycling from extracellular binding sites and hepatic glucose 6-phosphate can be measured by difference between [1,2- 3 H]-2-deoxy-D-glucose and [1- 3 H]-L-glucose, and the difference in irreversible loss of the two will measure extrahepatic uptake of D-glucose. Recycling via Cori-alanine cycle plus CO 2 is the difference in irreversible loss measured by using [6- 3 H]-glucose and [U- 14 C]-D-glucose. Recycling via the hexose monophosphate pathway can be determined by difference in irreversible loss between [1- 3 H]-D-glucose and [6- 3 H]-D-glucose. Recycling via CO 2 and glycerol must be measured directly with [U- 14 C]glucose, bicarbonate, and glycerol. Recycling via hepatic glycogen can be estimated by subtracting all other measured chemical recycling from total chemical recycling. This review describes means to quantify glucose recycling in vivo, enabling studies of mechanisms for conservation and utilization of glucose. 54 references

Antinociceptive effect of purine nucleotides.

Science.gov (United States)

Mello, C F; Begnini, J; De-La-Vega, D D; Lopes, F P; Schwartz, C C; Jimenez-Bernal, R E; Bellot, R G; Frussa-Filho, R

1996-10-01

The antinociceptive effect of purine nucleotides administered systematically (sc) was determined using the formalin and writhing tests in adult male albino mice. The mechanisms underlying nucleotide-induced antinociception were investigated by preinjecting the animals (sc) with specific antagonists for opioid (naloxone, 1 mg/kg), purinergic P1 (caffeine, 5, 10, of 30 mg/kg); theophylline, 10 mg/kg) or purinergic P2 receptors (suramin, 100 mg/kg; Coomassie blue, 30-300 mg/kg; quinidine, 10 mg/kg). Adenosine, adenosine monophosphate (AMP), diphosphate (ADP) and triphosphate (ATP) caused a reduction in the number of writhes and in the time of licking the formalin-injected paw. Naloxone had no effect on adenosine- or adenine nucleotide-induced antinociception. Caffeine (30 mg/kg) and theophylline (10 mg/kg) reversed the antinociceptive action of adenosine and adenine nucleotide derivatives in both tests. P2 antagonists did not reverse adenine nucleotide-induced antinociception. These results suggest that antinociceptive effect of adenine nucleotides is mediated by adenosine.

MUTATIONAL SYNERGISM BETWEEN RADIATIONS AND METHYLATED PURINES IN ESCHERICHIA COLI

Science.gov (United States)

Doneson, Ira N.; Shankel, Delbert M.

1964-01-01

Doneson, Ira N. (University of Kansas, Lawrence), and Delbert M. Shankel. Mutational synergism between radiations and methylalted purines in Escherichia coli. J. Bacteriol. 87:61–67. 1964.—A synergistic mutational effect was demonstrated between low doses of ultraviolet light and the methylated purines caffeine, theophylline, and theobromine. Caffeine produced the greatest effect and theobromine the least effect. The magnitude of the synergism was inversely related to the ultraviolet dosage. A large percentage of the synergistic effect could be “photoprevented” by exposure of the ultraviolet-treated cells to white light prior to exposure to the analogues. The consequence of the combined treatment occurred only when the chemical treatment followed the ultraviolet treatment. Furthermore, it was necessary to administer the chemical treatment soon after the ultraviolet treatment or the mutants were “lost.” When cells were treated with low dosages of ultraviolet light and of X irradiation (X ray), the result was merely additive, and combinations of X ray and chemical treatment yielded no synergism. Synchronous growth studies indicated that a particular growth stage of the organisms was most susceptible to the synergistic effect. The mutation studied was that of Escherichia coli B/r to high-level streptomycin resistance. PMID:14102875

The importance of recycling - Responsible recycling

International Nuclear Information System (INIS)

Svensson, Joens Petter

2014-01-01

7 times the total emissions from Sweden are saved each year by the recycling industry. It reduces CO 2 emissions and saves the environment. In fact it annually reduces global CO 2 emissions by 500 million tons, which is more than what is being emitted by the world wide aviation industry. Recycling of iron and steel saves 74% energy and reduces water and air pollution by respectively 76% and 86%, compared to primary production. It provides new raw materials and contributes to save energy. There's no sense in producing goods in a permanent material like plastics, that's supposed to be used only once. It's a huge waste of resources. Today the recycling industry provides half of the world's raw materials and this figure is set to increase. It's about environmentally sound management of resources. It's about plain common sense. There has to be a political willingness to facilitate recycling in every way. And from a corporate perspective social responsibility is becoming an increasingly important competitive edge. This is also a communication issue, it has to be a fact that is well known to the market when a company is doing valuable environmental work. We also need a well functioning global market with easy to understand regulations to facilitate global trade. The global demand for recycled materials should influence their collection and use. Fraud and theft has also to be kept at bay which calls for a close collaboration between organizations such as The International Chamber of Commerce, The International Trade Council and the International Maritime Bureau of the commercial crime services. Increasing recycling is the only way to go if we want to minimize our effect on the environment. We have to remember that recycling is essential for the environment. An increase would be a tremendous help to reduce the green house effect. Increasing recycling is not rocket science. We know how to do it, we just have to decide to go through with it

Astrocyte dysfunction following molybdenum-associated purine loading could initiate Parkinson's disease with dementia.

Science.gov (United States)

Bourke, Christopher A

2018-01-01

Sporadic or idiopathic Parkinson's disease is a movement disorder with a worldwide distribution, a long pre-clinical latent period and a frequent association with dementia. The combination of molybdenum deficiency and purine ingestion could explain the movement disorder, the distribution, the latent period and the dementia association. Recent studies in sheep have shown that molybdenum deficiency enables some dietary purines to accumulate in the central nervous system. This causes astrocyte dysfunction, altered neuromodulation and eventually irreversible central nervous system disease. Humans and sheep share the ability to salvage purines and this ability places humans at risk when they ingest xanthosine, inosine, adenosine and guanosine. Adenosine ingestion in molybdenum-deficient humans will lead to adenosine loading and potentially a disturbance to the A2a adenosine receptors in the nigro-striatum. This could result in Parkinson's disease. Guanosine ingestion in molybdenum-deficient humans will lead to guanosine loading and potentially a disturbance to the guanosine receptors in the hippocampus, amygdala and ventral striatum. This could result in dementia. The molybdenum content of the average daily diet in the United States is 0.07 ppm and in the United Kingdom 0.04 ppm. Central nervous system disease occurs in sheep at <0.04 ppm. Consistent with the role proposed for molybdenum deficiency in Parkinson's disease is the observation that affected individuals have elevated sulfur amino acid levels, depressed sulfate levels, and depressed uric acid levels. Likewise the geographical distribution of Parkinson's dementia complex on Guam corresponds with the distribution of molybdenum-deficient soils hence molybdenum-deficient food gardens on that island.

Recycling Facilities - Land Recycling Cleanup Locations

Data.gov (United States)

NSGIC Education | GIS Inventory — Land Recycling Cleanup Location Land Recycling Cleanup Locations (LRCL) are divided into one or more sub-facilities categorized as media: Air, Contained Release or...

Nuclear recycling

International Nuclear Information System (INIS)

Spinrad, B.I.

1985-01-01

This paper discusses two aspects of the economics of recycling nuclear fuel: the actual costs and savings of the recycling operation in terms of money spent, made, and saved; and the impact of the recycling on the future cost of uranium. The authors review the relevant physical and chemical processes involved in the recycling process. Recovery of uranium and plutonium is discussed. Fuel recycling in LWRs is examined and a table presents the costs of reprocessing and not reprocessing. The subject of plutonium in fast reactors is addressed. Safeguards and weapons proliferation are discussed

Anion-exchange analysis of isotopically labelled nucleotides, nucleosides, and bases in metabolic disorders

International Nuclear Information System (INIS)

Nissinen, E.A.O.

1987-01-01

This paper on the importance of cellular purines and pyrimidines is evidenced by the multitude of diseases, such as hyperuricemia, orotic aciduria, gout, Lesch-Nyhan syndrome, immunodeficiencies with B- and T-cell dysfunctions, etc. which result from aberrant metabolism. In addition, the use of purine and pyrimidine analogs in chemotherapy is of growing interest. Purine metabolism consists of a complex network of biochemical pathway. These pathways are under complicated feedback regulation and there also exists a close relationship between purine and pyrimidine metabolism. In addition, these pathways interact with those of the carbohydrate, amino acid, and energy metabolism. Since metabolic pathways are closely interrelated, a change in the concentration of a particular metabolite may lead to many changes in the overall metabolic profiles. For instance, in the area of nucleotide metabolism, the inhibition of IMP dehydrogenase by mycophenolic acid leads to various changes in both purine and pyrimidine nucleotide pools. Inhibition of de nova purine biosynthesis by methotrexate leads to many changes in purine and pyrimidine ribonucleotides and deoxyribonucleotides. Thus, the simultaneous measurement of all cellular purine and pyrimidine metabolites from individuals whose metabolism is altered, either by a metabolic disease or by the action of drugs, may further our understanding of cellular metabolism

The evolutionary fate of the genes encoding the purine catabolic enzymes in hominoids, birds, and reptiles.

Science.gov (United States)

Keebaugh, Alaine C; Thomas, James W

2010-06-01

Gene loss has been proposed to play a major role in adaptive evolution, and recent studies are beginning to reveal its importance in human evolution. However, the potential consequence of a single gene-loss event upon the fates of functionally interrelated genes is poorly understood. Here, we use the purine metabolic pathway as a model system in which to explore this important question. The loss of urate oxidase (UOX) activity, a necessary step in this pathway, has occurred independently in the hominoid and bird/reptile lineages. Because the loss of UOX would have removed the functional constraint upon downstream genes in this pathway, these downstream genes are generally assumed to have subsequently deteriorated. In this study, we used a comparative genomics approach to empirically determine the fate of UOX itself and the downstream genes in five hominoids, two birds, and a reptile. Although we found that the loss of UOX likely triggered the genetic deterioration of the immediate downstream genes in the hominoids, surprisingly in the birds and reptiles, the UOX locus itself and some of the downstream genes were present in the genome and predicted to encode proteins. To account for the variable pattern of gene retention and loss after the inactivation of UOX, we hypothesize that although gene loss is a common fate for genes that have been rendered obsolete due to the upstream loss of an enzyme a metabolic pathway, it is also possible that same lack of constraint will foster the evolution of new functions or allow the optimization of preexisting alternative functions in the downstream genes, thereby resulting in gene retention. Thus, adaptive single-gene losses have the potential to influence the long-term evolutionary fate of functionally interrelated genes.

Synthesis of some glycoside analogs and related compounds from 9-amino-6-(methylthio)-9H-purine.

Science.gov (United States)

Temple, C; Kussner, C L; Montgomery, J A

1975-12-01

Additional information on the anticancer activity of 9-amino-9H-purine-6(1H)-thione and its derivatives was sought by the synthesis of some 9-(substituted amino)-6-(methylthio)-9H-purines in which the 9-substituent contained functional groups capable of either reversible or irreversible binding with an enzymatic site. Condensation of 9-amino-6-(methylthio)-9H-purine (1) with some carbonyl compounds followed by hydride reduction of the azomethine linkage in the intermediates leads to the 2-pyrrolylmethyl (8), 2,3,4-trihydroxybutyl (10), and the 1,5-dihydroxy-2- and 3-pentyl (11 and 12) compounds. A 4-hydroxybutyl derivative (13) was obtained by alkylation of 18, the 9-acetyl derivative of 1, with 4-chlorobutyl acetate followed by saponification. The cyclization of 13 and 11 with a sulfonyl chloride gave the 9-pyrrolidin-1-yl (27) and the 9-[2-(tosyloxymethyl)pyrrolidin-1-yl] (28), respectively. Acylation of 1 with ethyl L-2-pyrrolidine-5-carboxylate and ethyl 1-methyl-5-pyrrolidone-3-carboxylate, respectively, in Me2SO containing NaH gave the corresponding amides 15 and 17. Alkylation of 18 with 1-bromo-2-chloroethane and epichlorohydrin gave the N-(2-chloroethyl) and N-(1,2-epoxy-3-propyl) derivatives 19 and 20. The chloro group of the chlorobutyl derivative of 18 was displaced with KSCN and NaN3, respectively, to give the thiocyanate and azido derivatives 23 and 24. Hydrogenation of the latter gave the amine (25), which was acylated with ethyl chloroformate to give the (ethoxycarbonyl)amino compound 26. None of these compounds showed activity against L1210 leukemia cells implanted ip in mice on a single-dose schedule, suggesting that the activity observed in the simpler 9-aminopurines resulted from cleavage of the hydrazino linkage to give pH-purine-6(1H)-thione.

Retromer guides STxB and CD8-M6PR from early to recycling endosomes, EHD1 guides STxB from recycling endosome to Golgi

Science.gov (United States)

McKenzie, Jenna E.; Raisley, Brent; Zhou, Xin; Naslavsky, Naava; Taguchi, Tomohiko; Caplan, Steve; Sheff, David

2012-01-01

Retrograde trafficking transports proteins, lipids and toxins from the plasma membrane to the Golgi and ER. To reach the Golgi, these cargos must transit the endosomal system, consisting of early endosomes, recycling endosomes, late endosomes and lysosomes. All cargos pass through early endosomes, but may take different routes to the Golgi. Retromer dependent cargos bypass the late endosomes to reach the Golgi. We compared how two very different retromer dependent cargos negotiate the endosomal sorting system. Shiga toxin B, bound to the external layer of the plasma membrane, and chimeric CD8-Mannose-6-Phosphate Receptor, which is anchored via a transmembrane domain. Both appear to pass through the recycling endosome. Ablation of the recycling endosome diverted both of these cargos to an aberrant compartment and prevented them from reaching the Golgi. Once in the recycling endosome, Shiga toxin required EHD1 to traffic to the TGN, while the CD8-Mannose-6-Phosphate Receptor was not significantly dependent on EHD1. Knockdown of retromer components left cargo in the early endosomes, suggesting that it is required for retrograde exit from this compartment. This work establishes the recycling endosome as a required step in retrograde traffic of at least these two retromer dependent cargos. Along this pathway, retromer is associated with EE to recycling endosome traffic, while EHD1 is associated with recycling endosome to TGN traffic of STxB. PMID:22540229

Reprogramming One-Carbon Metabolic Pathways To Decouple l-Serine Catabolism from Cell Growth in Corynebacterium glutamicum.

Science.gov (United States)

Zhang, Yun; Shang, Xiuling; Lai, Shujuan; Zhang, Yu; Hu, Qitiao; Chai, Xin; Wang, Bo; Liu, Shuwen; Wen, Tingyi

2018-02-16

l-Serine, the principal one-carbon source for DNA biosynthesis, is difficult for microorganisms to accumulate due to the coupling of l-serine catabolism and microbial growth. Here, we reprogrammed the one-carbon unit metabolic pathways in Corynebacterium glutamicum to decouple l-serine catabolism from cell growth. In silico model-based simulation showed a negative influence on glyA-encoding serine hydroxymethyltransferase flux with l-serine productivity. Attenuation of glyA transcription resulted in increased l-serine accumulation, and a decrease in purine pools, poor growth and longer cell shapes. The gcvTHP-encoded glycine cleavage (Gcv) system from Escherichia coli was introduced into C. glutamicum, allowing glycine-derived 13 CH 2 to be assimilated into intracellular purine synthesis, which resulted in an increased amount of one-carbon units. Gcv introduction not only restored cell viability and morphology but also increased l-serine accumulation. Moreover, comparative proteomic analysis indicated that abundance changes of the enzymes involved in one-carbon unit cycles might be responsible for maintaining one-carbon unit homeostasis. Reprogramming of the one-carbon metabolic pathways allowed cells to reach a comparable growth rate to accumulate 13.21 g/L l-serine by fed-batch fermentation in minimal medium. This novel strategy provides new insights into the regulation of cellular properties and essential metabolite accumulation by introducing an extrinsic pathway.

Metabolism of xanthine and hypoxanthine in the tea plant (Thea sinensis L.).

Science.gov (United States)

Suzuki, T; Takahashi, E

1975-01-01

1. The metabolism of xanthine and hypoxanthine in excised shoot tips of tea was studied with micromolar amounts of [2(-14)C]xanthine or [8(-14)C]hypoxanthine. Almost all of the radioactive compounds supplied were utilized by tea shoot tips by 30 h after their uptake. 2. The main products of [2(-14)C]xanthine and [8(-14)C]hypoxanthine metabolism in tea shoots were urea, allantoin and allantoic acid. There was also incorporation of the label into theobromine, caffeine and RNA purine nucleotides. 3. The results indicate that tea plants can catabolize purine bases by the same pathways as animals. It is also suggested that tea plants have the ability to snythesize purine nucleotides from glycine by the pathways of purine biosynthesis de novo and from hypoxanthine and xanthine by the pathway of purine salvage. 4. The results of incorporation of more radioactivity from [8(-14)C]hypoxanthine than from [2(-14)C]xanthine into RNA purine nucleotides and caffeine suggest that hypoxanthine is a more effective precursor of caffeine biosynthesis than xanthine. The formation of caffeine from hypoxanthine is a result of nucleotide synthesis via the pathway of purine salvage. PMID:1147906

Radiological control criteria for materials considered for recycle and reuse

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Hill, R.L.; Aaberg, R.L.; Wallo, A. III

1994-11-01

Pacific Northwest Laboratory (PNL) is conducting technical analyses to support the US Department of Energy (DOE), Office of Environmental Guidance, Air, Water, and Radiation Division (DOE/EH-232) in developing radiological control criteria for recycling or reuse of metals or equipment containing residual radioactive contamination from DOE operations. The criteria, framed as acceptable concentrations for release of materials for recycling or reuse, are risk-based and were developed through analysis of generic radiation exposure scenarios and pathways. The analysis includes evaluation of relevant radionuclides, potential mechanisms of exposure, and non-health-related impacts of residual radioactivity on electronics and film. The analysis considers 42 key radionuclides that DOE operations are known to generate and that may be contained in recycled or reused metals or equipment. Preliminary results are compared with similar results reported by the International Atomic Energy Agency, by radionuclide grouping

Modelling Recycling Targets

DEFF Research Database (Denmark)

Hill, Amanda Louise; Leinikka Dall, Ole; Andersen, Frits M.

2014-01-01

Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22......% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...... the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...

Unconventional recycling

Energy Technology Data Exchange (ETDEWEB)

White, K.M.

1996-05-01

Despite advances made in recycling technology and markets for materials over the past few years, recycling at convention centers, particularly on the show floor itself, can be a vexing problem. Part of the problem lies in the fact that recycling at convention centers has more to do with logistics than it does with these industry trends. However, given the varied nature of convention centers, and the shows they book, a rigid approach to recycling at convention centers is not always feasible. Like the numerous different curbside programs serving communities across the country, what works for one convention center--and one show--many not work for another. These difficulties notwithstanding, more convention centers are offering recycling programs today, and more groups booking conventions these days have begun requesting recycling services.

Recycling Lesson Plan

Science.gov (United States)

Okaz, Abeer Ali

2013-01-01

This lesson plan designed for grade 2 students has the goal of teaching students about the environmental practice of recycling. Children will learn language words related to recycling such as: "we can recycle"/"we can't recycle" and how to avoid littering with such words as: "recycle paper" and/or "don't throw…

Typology of Options for Metal Recycling: Australia’s Perspective

Directory of Open Access Journals (Sweden)

Artem Golev

2015-12-01

Full Text Available While Australia has traditionally relied on obtaining metals from primary sources (namely mined natural resources, there is significant potential to recover metals from end-of-life-products and industrial waste. Although any metals recycling value chain requires a feasible technology at its core, many other non-technical factors are key links in the chain, which can compromise the overall viability to recycle a commodity and/or product. The “Wealth from Waste” Cluster project funded by the Commonwealth Scientific Industrial Research Organisation (CSIRO Flagship Collaboration Fund and partner universities is focusing on identifying viable options to “mine” metals contained in discarded urban infrastructure, manufactured products and consumer goods. A key aspect of this research is to understand the critical non-technical barriers and system opportunities to enhance rates of metals recycling in Australia. Work to date has estimated the mass and current worth of metals in above ground resources. Using these outcomes as a basis, a typology for different options for (metal reuse and recycling has been developed to classify the common features, which is presented in this article. In addition, the authors investigate the barriers and enablers in the recycling value chain, and propose a set of requirements for a feasible pathway to close the material loop for metals in Australia.

Metabolic evidence that serosal sodium does not recycle through the active transepithelial transport pathway of toad bladder.

Science.gov (United States)

Canessa, M; Labarca, P; Leaf, A

1976-12-25

The possibility that sodium from the serosal bathing medium "back diffuses" into the active sodium transport pool within the mucosal epithelial cell of the isolated toad bladder was examined by determining the effect on the metabolism of the tissue of removing sodium from the serosal medium. It was expected that if recycling of serosal sodium did occur through the active transepithelial transport pathway of the isolated toad bladder, removal of sodium from the serosal medium would reduce the rate of CO2 production by the tissue and enhance of stoichiometric ratio of sodium ions transported across the bladder per molecula of sodium transport dependent CO2 produced simultaneously by the bladder (JNa/JCO2). The data revealed no significant change in this ratio (17.19 with serosal sodium and 16.13 after replacing serosal sodium with choline). Further, when transepithelial sodium transport was inhibited (a) by adding amiloride to the mucosal medium, or (b) by removing sodium from the mucosal medium, subsequent removal of sodium from the serosal medium, or (c) addition of ouabain failed to depress the basal rate of CO2 production by the bladder [(a)rate of basal, nontransport related, CO2 production (JbCO2) equals 1.54 +/- 0.52 with serosal sodium and 1.54 +/- 0.37 without serosal sodium; (b) Jb CO2 equals 2.18 +/- 0.21 with serosal sodium and 2.09 +/- 0.21 without serosal sodium; (c) 1.14 +/- 0.26 without ouabain and 1.13 +/- 0.25 with ouabain; unite of JbCO2 are nmoles mg d.w.-1 min-1]. The results support the hypothesis that little, if any, recycling of serosal sodium occurs in the total bladder.

Aplicaci??n de humedales artificiales para la depuraci??n de purines de granjas porcinas

OpenAIRE

Blanco Rubio, Iv??n

2014-01-01

204 p. El principal objetivo de este trabajo de investigaci??n es proporcionar informaci??n relevante sobre el funcionamiento y dimensionado de los sistemas de humedales artificiales de tipo horizontal para el tratamiento de la fracci??n l??quida de purines de cerdo

Waste material recycling: Assessment of contaminants limiting recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn

systematically investigated. This PhD project provided detailed quantitative data following a consistent approach to assess potential limitations for the presence of chemicals in relation to material recycling. Paper and plastics were used as illustrative examples of materials with well-established recycling...... schemes and great potential for increase in recycling, respectively. The approach followed in the present work was developed and performed in four distinct steps. As step one, fractional composition of waste paper (30 fractions) and plastics (9 fractions) from households in Åbenrå municipality (Southern...... detrimental to their recycling. Finally, a material flow analysis (MFA) approach revealed the potential for accumulation and spreading of contaminants in material recycling, on the example of the European paper cycle. Assessment of potential mitigation measures indicated that prevention of chemical use...

Recycling carbon dioxide during xylose fermentation by engineered Saccharomyces cerevisiae

Science.gov (United States)

In this study, we introduced the ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and phosphoribulokinase (PRK) into an engineered S. cerevisiae (SR8) harboring the XR/XDH pathway and up-regulated PPP 10, to enable CO2 recycling through a synthetic rPPP during xylose fermentation (Fig. 1). ...

Radiological control criteria for materials considered for recycle and reuse

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Hill, R.L.; Aaberg, R.L.; Wallo, A. III.

1995-01-01

Pacific Northwest Laboratory (PNL) is conducting technical analyses to support the U.S. Department of Energy (DOE), Office of Environmental Guidance, Air, Water, and Radiation Division (DOE/EH-232) in developing radiological control criteria for recycling or reuse of metals or equipment containing residual radioactive contamination from DOE operations. The criteria, framed as acceptable concentrations for release of materials for recycling or reuse, are risk-based and were developed through analysis of generic radiation exposure scenarios and pathways. The analysis includes evaluation of relevant radionuclides, potential mechanisms of exposure, and non-health-related impacts of residual radioactivity on electronics and film. The analysis considers 42 key radionuclides that DOE operations are known to generate and that may be contained in recycled or reused metals or equipment. The preliminary results are compared with similar results reported by the International Atomic Energy Agency, by radionuclide grouping. (author)

Inhibition of DNA glycosylases via small molecule purine analogs.

Directory of Open Access Journals (Sweden)

Aaron C Jacobs

Full Text Available Following the formation of oxidatively-induced DNA damage, several DNA glycosylases are required to initiate repair of the base lesions that are formed. Recently, NEIL1 and other DNA glycosylases, including OGG1 and NTH1 were identified as potential targets in combination chemotherapeutic strategies. The potential therapeutic benefit for the inhibition of DNA glycosylases was validated by demonstrating synthetic lethality with drugs that are commonly used to limit DNA replication through dNTP pool depletion via inhibition of thymidylate synthetase and dihydrofolate reductase. Additionally, NEIL1-associated synthetic lethality has been achieved in combination with Fanconi anemia, group G. As a prelude to the development of strategies to exploit the potential benefits of DNA glycosylase inhibition, it was necessary to develop a reliable high-throughput screening protocol for this class of enzymes. Using NEIL1 as the proof-of-principle glycosylase, a fluorescence-based assay was developed that utilizes incision of site-specifically modified oligodeoxynucleotides to detect enzymatic activity. This assay was miniaturized to a 1536-well format and used to screen small molecule libraries for inhibitors of the combined glycosylase/AP lyase activities. Among the top hits of these screens were several purine analogs, whose postulated presence in the active site of NEIL1 was consistent with the paradigm of NEIL1 recognition and excision of damaged purines. Although a subset of these small molecules could inhibit other DNA glycosylases that excise oxidatively-induced DNA adducts, they could not inhibit a pyrimidine dimer-specific glycosylase.

Open-loop recycling: A LCA case study of PET bottle-to-fibre-recycling

NARCIS (Netherlands)

Shen, L.; Worrell, E.; Patel, M.K.

2010-01-01

This study assesses the environmental impact of polyethylene terephthalate (PET) bottle-to-fibre recycling using the methodology of life-cycle assessment (LCA). Four recycling cases, including mechanical recycling, semi-mechanical recycling, back-to-oligomer recycling and back-to-monomer recycling

Blockage of the pyrimidine biosynthetic pathway affects riboflavin production in Ashbya gossypii.

Science.gov (United States)

Silva, Rui; Aguiar, Tatiana Q; Domingues, Lucília

2015-01-10

The Ashbya gossypii riboflavin biosynthetic pathway and its connection with the purine pathway have been well studied. However, the outcome of genetic alterations in the pyrimidine pathway on riboflavin production by A. gossypii had not yet been assessed. Here, we report that the blockage of the de novo pyrimidine biosynthetic pathway in the recently generated A. gossypii Agura3 uridine/uracil auxotrophic strain led to improved riboflavin production on standard agar-solidified complex medium. When extra uridine/uracil was supplied, the production of riboflavin by this auxotroph was repressed. High concentrations of uracil hampered this (and the parent) strain growth, whereas excess uridine favored the A. gossypii Agura3 growth. Considering that the riboflavin and the pyrimidine pathways share the same precursors and that riboflavin overproduction may be triggered by nutritional stress, we suggest that overproduction of riboflavin by the A. gossypii Agura3 may occur as an outcome of a nutritional stress response and/or of an increased availability in precursors for riboflavin biosynthesis, due to their reduced consumption by the pyrimidine pathway. Copyright © 2014 Elsevier B.V. All rights reserved.

Can Crystal Symmetry and Packing Influence the Active Site Conformation of Homohexameric Purine Nucleoside Phosphorylases?

Directory of Open Access Journals (Sweden)

Marija Luić

2016-06-01

Full Text Available It is generaly believed that enzymes retain most of their functionality in the crystal form due to the large solvent content of protein crystals. This is facilitated by the fact that their natural environment in solution is not too far from the one found in the crystal form. Nevertheless, if the nature of the enzyme is such to require conformational changes, overcoming of the crystal packing constraints may prove to be too difficult. Such conformational change is present in one class of enzymes (purine nucleoside phosphorylases, that is the subject of our scientific interest for many years. The influence of crystal symmetry and crystal packing on the conformation of the active sites in the case of homohexameric purine nucleoside phosphorylases is presented and analysed. This work is licensed under a Creative Commons Attribution 4.0 International License.

Flow of nucleic acids from the rumen and recovery of purine derivatives in the urine of cattle and buffaloes

International Nuclear Information System (INIS)

Soejono, M.; Yusiati, L.M.; Bachrudin, Z.; Budhi, S.P.S.; Widyobroto, B.P.; Utomo, R.

2004-01-01

An experiment was conducted to determine the flow of nucleic acids from the rumen to duodenum. Two duodenal-cannulated each of male Ongole cattle and buffaloes aged three to four years were used and fed a mixture of king grass and rice bran (70:30 DM basis). At 95% and 60% of the voluntary intake in three weeks each before morning feeding period. Cr-mordanted alfalfa was used as a marker. The excretion of allantoin, uric acid, purine derivatives, and creatinine and the PDC index were higher in cattle than buffaloes at both levels of intake (P < 0.05). There were no difference between cattle and buffaloes with regard to the flow of RNA when expressed on digestible organic matter intake (DOMI), flow rate of RNA/kg DOMI, or flow rate of crude protein/kg DOMI. It can be concluded that the differences in urine excretion of purine derivatives between cattle and buffalo is not due to the differences in the amount of rumen microbial protein synthesis, but due to differences in purine metabolism between cattle and buffaloes. (author)

Altered Mitochondria, Protein Synthesis Machinery, and Purine Metabolism Are Molecular Contributors to the Pathogenesis of Creutzfeldt-Jakob Disease.

Science.gov (United States)

Ansoleaga, Belén; Garcia-Esparcia, Paula; Llorens, Franc; Hernández-Ortega, Karina; Carmona Tech, Margarita; Antonio Del Rio, José; Zerr, Inga; Ferrer, Isidro

2016-06-12

Neuron loss, synaptic decline, and spongiform change are the hallmarks of sporadic Creutzfeldt-Jakob disease (sCJD), and may be related to deficiencies in mitochondria, energy metabolism, and protein synthesis. To investigate these relationships, we determined the expression levels of genes encoding subunits of the 5 protein complexes of the electron transport chain, proteins involved in energy metabolism, nucleolar and ribosomal proteins, and enzymes of purine metabolism in frontal cortex samples from 15 cases of sCJD MM1 and age-matched controls. We also assessed the protein expression levels of subunits of the respiratory chain, initiation and elongation translation factors of protein synthesis, and localization of selected mitochondrial components. We identified marked, generalized alterations of mRNA and protein expression of most subunits of all 5 mitochondrial respiratory chain complexes in sCJD cases. Expression of molecules involved in protein synthesis and purine metabolism were also altered in sCJD. These findings point to altered mRNA and protein expression of components of mitochondria, protein synthesis machinery, and purine metabolism as components of the pathogenesis of CJD. © 2016 American Association of Neuropathologists, Inc. All rights reserved.

Comprehensive multipathway risk assessment of chemicals associated with recycled ("crumb") rubber in synthetic turf fields.

Science.gov (United States)

Peterson, Michael K; Lemay, Julie C; Pacheco Shubin, Sara; Prueitt, Robyn L

2018-01-01

Thousands of synthetic turf fields in the US are regularly used by millions of individuals (particularly children and adolescents). Although many safety assessments have concluded that there are low or negligible risks related to exposure to chemicals found in the recycled rubber used to make these fields, concerns remain about the safety of this product. Existing studies of recycled rubber's potential health risks have limitations such as small sample sizes and limited evaluation of relevant exposure pathways and scenarios. Conduct a comprehensive multipathway human health risk assessment (HHRA) of exposure to chemicals found in recycled rubber. All available North American data on the chemical composition of recycled rubber, as well as air sampling data collected on or near synthetic turf fields, were identified via a literature search. Ingestion, dermal contact, and inhalation pathways were evaluated according to US Environmental Protection Agency (US EPA) guidance, and exposure scenarios for adults, adolescents, and children were considered. Estimated non-cancer hazards and cancer risks for all the evaluated scenarios were within US EPA guidelines. In addition, cancer risk levels for users of synthetic turf field were comparable to or lower than those associated with natural soil fields. This HHRA's results add to the growing body of literature that suggests recycled rubber infill in synthetic turf poses negligible risks to human health. This comprehensive assessment provides data that allow stakeholders to make informed decisions about installing and using these fields. Copyright © 2017 Elsevier Inc. All rights reserved.

Behaviour of Recycled Coarse Aggregate Concrete: Age and Successive Recycling

Science.gov (United States)

Sahoo, Kirtikanta; Pathappilly, Robin Davis; Sarkar, Pradip

2016-06-01

Recycled Coarse Aggregate (RCA) concrete construction technique can be called as `green concrete', as it minimizes the environmental hazard of the concrete waste disposal. Indian standard recommends target mean compressive strength of the conventional concrete in terms of water cement ratio ( w/ c). The present work is an attempt to study the behaviour of RCA concrete from two samples of parent concrete having different age group with regard to the relationship of compressive strength with water cement ratios. Number of recycling may influence the mechanical properties of RCA concrete. The influence of age and successive recycling on the properties such as capillary water absorption, drying shrinkage strain, air content, flexural strength and tensile splitting strength of the RCA concrete are examined. The relationship between compressive strength at different w/ c ratios obtained experimentally is investigated for the two parameters such as age of parent concrete and successive recycling. The recycled concrete using older recycled aggregate shows poor quality. While the compressive strength reduces with successive recycling gradually, the capillary water absorption increases abruptly, which leads to the conclusion that further recycling may not be advisable.

SYNTHESIS OF NEW TWO DERIVATIVES OF 6-MERCAPTOPURINE (6MP) 6-[5-PYRIDINE-4-YL- 1, 2, 3, 4-OXADIAZOLE-2-YL)DITHIOL]-9H-PURINE (38) AND 9H-PURINE-6-YL-BENYLDITHIOCARBAMATE (45) WITH CYTOTOXICITY RESULTS FROM THE NATIONAL CANCER INSTITUTE'S ANTICANCER DRUG SCREEN

OpenAIRE

Mohammed Hassan Mohammed et al

2012-01-01

6-[(5-pyridine-yl-1, 2, 3, 4-oxadiazole-2-yl)dithiol]-9H-purine (38) and 9H-purine-6yl-benzyldithiocarbamate (45) are synthesized as possible prodrugs for 6-mercaptopurine(6-MP). The generation of the compounds 38, 42, 45 and 48 were accomplished following multistep reaction procedures. The reaction and purity of the products were checked by TLC, the structure of the final compounds and their intermediates were confirmed by their melting points, infra red spectroscopy and whether differences ...

Control criteria for residual contamination in materials considered for recycle and reuse

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Hill, R.L.; Aaberg, R.L.

1993-11-01

Pacific Northwest Laboratory (PNL) is collecting data and conducting technical analyses to support the US Department of Energy (DOE), Office of Environmental Guidance, Air, Water, and Radiation Division (DOE/EH-232) in determining the feasibility of developing radiological control criteria for recycling or reuse of metals or equipment containing residual radioactive contamination from DOE operations. The criteria, framed as acceptable concentrations for release of materials for recycling or reuse, will be risk-based and will be developed through analysis of radiation exposure scenarios and pathways. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and non-health-related impacts of residual radioactivity on electronics and film. The analyses will consider 42 key radionuclides that are generated during DOE operations and may be contained in recycled or reused metals or equipment

Novel modified purine bases and nucleosides: new methodologies of synthesis and biological activity

Czech Academy of Sciences Publication Activity Database

Hocek, Michal

-, č. 49 (2005), s. 29-30 ISSN 0261-3166. [International Symposium on Nucleic Acids Chemistry /4./. Fukuoka, 20.09.2005-22.09.2005] R&D Projects: GA ČR(CZ) GA203/03/0035; GA MŠk(CZ) 1M0508 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * nucleosides * synthesis Subject RIV: CC - Organic Chemistry

Targeting the cell cycle and the PI3K pathway: a possible universal strategy to reactivate innate tumor suppressor programmes in cancer cells.

Science.gov (United States)

David-Pfeuty, Thérèse; Legraverend, Michel; Ludwig, Odile; Grierson, David S

2010-04-01

Corruption of the Rb and p53 pathways occurs in virtually all human cancers. This could be because it lends oncogene-bearing cells a surfeit of Cdk activity and growth, enabling them to elaborate strategies to evade tumor-suppressive mechanisms and divide inappropriately. Targeting both Cdk activities and the PI3K pathway might be therefore a potentially universal means to palliate their deficiency in cancer cells. We showed that the killing efficacy of roscovitine and 16 other purines and potentiation of roscovitine-induced apoptosis by the PI3K inhibitor, LY294002, decreased with increasing corruption of the Rb and p53 pathways. Further, we showed that purines differing by a single substitution, which exerted little lethal effect on distant cell types in rich medium, could display widely-differing cytotoxicity profiles toward the same cell types in poor medium. Thus, closely-related compounds targeting similar Cdks may interact with different targets that could compete for their interaction with therapeutically-relevant Cdk targets. In the perspective of clinical development in association with the PI3K pathway inhibitors, it might thus be advisable to select tumor cell type-specific Cdk inhibitors on the basis of their toxicity in cell-culture-based assays performed at a limiting serum concentration sufficient to suppress their interaction with undesirable crossreacting targets whose range and concentration would depend on the cell genotype.

Pentose phosphates in nucleoside interconversion and catabolism.

Science.gov (United States)

Tozzi, Maria G; Camici, Marcella; Mascia, Laura; Sgarrella, Francesco; Ipata, Piero L

2006-03-01

Ribose phosphates are either synthesized through the oxidative branch of the pentose phosphate pathway, or are supplied by nucleoside phosphorylases. The two main pentose phosphates, ribose-5-phosphate and ribose-1-phosphate, are readily interconverted by the action of phosphopentomutase. Ribose-5-phosphate is the direct precursor of 5-phosphoribosyl-1-pyrophosphate, for both de novo and 'salvage' synthesis of nucleotides. Phosphorolysis of deoxyribonucleosides is the main source of deoxyribose phosphates, which are interconvertible, through the action of phosphopentomutase. The pentose moiety of all nucleosides can serve as a carbon and energy source. During the past decade, extensive advances have been made in elucidating the pathways by which the pentose phosphates, arising from nucleoside phosphorolysis, are either recycled, without opening of their furanosidic ring, or catabolized as a carbon and energy source. We review herein the experimental knowledge on the molecular mechanisms by which (a) ribose-1-phosphate, produced by purine nucleoside phosphorylase acting catabolically, is either anabolized for pyrimidine salvage and 5-fluorouracil activation, with uridine phosphorylase acting anabolically, or recycled for nucleoside and base interconversion; (b) the nucleosides can be regarded, both in bacteria and in eukaryotic cells, as carriers of sugars, that are made available though the action of nucleoside phosphorylases. In bacteria, catabolism of nucleosides, when suitable carbon and energy sources are not available, is accomplished by a battery of nucleoside transporters and of inducible catabolic enzymes for purine and pyrimidine nucleosides and for pentose phosphates. In eukaryotic cells, the modulation of pentose phosphate production by nucleoside catabolism seems to be affected by developmental and physiological factors on enzyme levels.

Specific recycling receptors are targeted to the immune synapse by the intraflagellar transport system

Science.gov (United States)

Finetti, Francesca; Patrussi, Laura; Masi, Giulia; Onnis, Anna; Galgano, Donatella; Lucherini, Orso Maria; Pazour, Gregory J.; Baldari, Cosima T.

2014-01-01

ABSTRACT T cell activation requires sustained signaling at the immune synapse, a specialized interface with the antigen-presenting cell (APC) that assembles following T cell antigen receptor (TCR) engagement by major histocompatibility complex (MHC)-bound peptide. Central to sustained signaling is the continuous recruitment of TCRs to the immune synapse. These TCRs are partly mobilized from an endosomal pool by polarized recycling. We have identified IFT20, a component of the intraflagellar transport (IFT) system that controls ciliogenesis, as a central regulator of TCR recycling to the immune synapse. Here, we have investigated the interplay of IFT20 with the Rab GTPase network that controls recycling. We found that IFT20 forms a complex with Rab5 and the TCR on early endosomes. IFT20 knockdown (IFT20KD) resulted in a block in the recycling pathway, leading to a build-up of recycling TCRs in Rab5+ endosomes. Recycling of the transferrin receptor (TfR), but not of CXCR4, was disrupted by IFT20 deficiency. The IFT components IFT52 and IFT57 were found to act together with IFT20 to regulate TCR and TfR recycling. The results provide novel insights into the mechanisms that control TCR recycling and immune synapse assembly, and underscore the trafficking-related function of the IFT system beyond ciliogenesis. PMID:24554435

2,6,9-Trisubstituted purines as CRK3 kinase inhibitors with antileishmanial activity in vitro

Czech Academy of Sciences Publication Activity Database

Řezníčková, Eva; Popa, Alexandr; Gucký, Tomáš; Zatloukal, Marek; Havlíček, Libor; Bazgier, Václav; Berka, K.; Jorda, Radek; Popa, Igor; Nasereddin, A.; Jaffe, Ch. L.; Kryštof, Vladimír; Strnad, Miroslav

2015-01-01

Roč. 25, č. 11 (2015), s. 2298-2301 ISSN 0960-894X R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Purine * Cyclin-dependent kinase * Leishmania Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.486, year: 2015

The regulation of aortic endothelial cells by purines and pyrimidines involves co-existing P2y-purinoceptors and nucleotide receptors linked to phospholipase C.

Science.gov (United States)

Wilkinson, G F; Purkiss, J R; Boarder, M R

1993-03-01

1. We have examined the phospholipase C responses in bovine aortic endothelial cells to purines (ATP, ADP and analogues) and the pyrimidine, uridine triphosphate (UTP). 2. The cells responded to purines in a manner consistent with the presence of P2y purinoceptors; both 2-methylthioadenosine 5'-triphosphate (2MeSATP) and adenosine 5'-0-(2-thiodiphosphate) (ADP beta S) were potent agonists (EC50 0.41 microM and 0.85 microM respectively) while beta, gamma-methylene ATP at 300 microM was not. 3. The cells also responded to UTP. The maximal response to UTP was less than that for either 2MeSATP and ADP beta S while adenosine 5'-0-(3-thiotriphosphate) (ATP gamma S) gave the largest maximal response. 4. The concentration-effect curve to UTP was additive in the presence of either 2MeSATP or ADP beta S. However, the concentration-effect curves to ATP gamma S reached the same maximum in the presence or absence of UTP. 5. Suramin, at concentrations between 10 microM and 100 microM was a competitive antagonist for the response to ADP beta S and 2MeSATP but not the response to UTP. 6. The results show that there are two separate, co-existing, receptor populations: P2y-purinoceptors (responding to purines) and nucleotide receptors (responding to both purines and pyrimidines). We conclude that purines such as ATP/ADP may regulate aortic endothelial cells by interacting with two phospholipase C-linked receptors.

Purine nucleoside phosphorylase deficiency in two unrelated Saudi patients

International Nuclear Information System (INIS)

Alangari, Abdullah; AlHarbi, Abdullah; AlGhonaium Abdulaziz; Santisteban, Ines; Hershfield, Michael

2009-01-01

Purine nucleoside phosphorylase (PNP) deficiency is a rare autosomal recessive metabolic disorder that results in combined immunodeficiency, neurologic dysfunction and autoimmunity. PNP deficiency has never been reported from Saudi Arabia or in patients with an Arabic ethnic background. We report on two Saudi girls with PNP deficiency. Both showed severe lymphopenia and neurological involvement. Sequencing of the PNP gene of one girl revealed a novel missense mutation Pro146>Leu in exon 4 due to a change in the codon from CCT>CTT. Expression of PNP (146L) cDNA in E coli indicated that the mutation greatly reduced, but did not completely eliminate PNP activity. (author)

Interactions of trimeric purine nucleoside phosphorylases with ground state analogues - calorimetric and fluorimetric studies

Czech Academy of Sciences Publication Activity Database

Wielgus-Kutrowska, B.; Frank, J.; Holý, Antonín; Koellner, G.; Bzowska, A.

2003-01-01

Roč. 22, 5/8 (2003), s. 1695-1698 ISSN 1525-7770 Grant - others:PCSR(PL) 6 P04A04416; PCSR(PL) 3 P04A03524 Institutional research plan: CEZ:AV0Z4055905 Keywords : purine nucleoside phosphorylase * fluorescence Subject RIV: CC - Organic Chemistry Impact factor: 0.813, year: 2003

Structural and catalytic effects of an invariant purine substitution in the hammerhead ribozyme: implications for the mechanism of acid–base catalysis

Science.gov (United States)

Schultz, Eric P.; Vasquez, Ernesto E.; Scott, William G.

2014-01-01

The hammerhead ribozyme catalyzes RNA cleavage via acid–base catalysis. Whether it does so by general acid–base catalysis, in which the RNA itself donates and abstracts protons in the transition state, as is typically assumed, or by specific acid–base catalysis, in which the RNA plays a structural role and proton transfer is mediated by active-site water molecules, is unknown. Previous biochemical and crystallographic experiments implicate an invariant purine in the active site, G12, as the general base. However, G12 may play a structural role consistent with specific base catalysis. To better understand the role of G12 in the mechanism of hammerhead catalysis, a 2.2 Å resolution crystal structure of a hammerhead ribozyme from Schistosoma mansoni with a purine substituted for G12 in the active site of the ribozyme was obtained. Comparison of this structure (PDB entry 3zd4), in which A12 is substituted for G, with three previously determined structures that now serve as important experimental controls, allows the identification of structural perturbations that are owing to the purine substitution itself. Kinetic measurements for G12 purine-substituted schistosomal hammerheads confirm a previously observed dependence of rate on the pK a of the substituted purine; in both cases inosine, which is similar to G in pK a and hydrogen-bonding properties, is unexpectedly inactive. Structural comparisons indicate that this may primarily be owing to the lack of the exocyclic 2-amino group in the G12A and G12I substitutions and its structural effect upon both the nucleotide base and phosphate of A9. The latter involves the perturbation of a previously identified and well characterized metal ion-binding site known to be catalytically important in both minimal and full-length hammerhead ribozyme sequences. The results permit it to be suggested that G12 plays an important role in stabilizing the active-site structure. This result, although not inconsistent with the

Structural and catalytic effects of an invariant purine substitution in the hammerhead ribozyme: implications for the mechanism of acid-base catalysis.

Science.gov (United States)

Schultz, Eric P; Vasquez, Ernesto E; Scott, William G

2014-09-01

The hammerhead ribozyme catalyzes RNA cleavage via acid-base catalysis. Whether it does so by general acid-base catalysis, in which the RNA itself donates and abstracts protons in the transition state, as is typically assumed, or by specific acid-base catalysis, in which the RNA plays a structural role and proton transfer is mediated by active-site water molecules, is unknown. Previous biochemical and crystallographic experiments implicate an invariant purine in the active site, G12, as the general base. However, G12 may play a structural role consistent with specific base catalysis. To better understand the role of G12 in the mechanism of hammerhead catalysis, a 2.2 Å resolution crystal structure of a hammerhead ribozyme from Schistosoma mansoni with a purine substituted for G12 in the active site of the ribozyme was obtained. Comparison of this structure (PDB entry 3zd4), in which A12 is substituted for G, with three previously determined structures that now serve as important experimental controls, allows the identification of structural perturbations that are owing to the purine substitution itself. Kinetic measurements for G12 purine-substituted schistosomal hammerheads confirm a previously observed dependence of rate on the pK(a) of the substituted purine; in both cases inosine, which is similar to G in pK(a) and hydrogen-bonding properties, is unexpectedly inactive. Structural comparisons indicate that this may primarily be owing to the lack of the exocyclic 2-amino group in the G12A and G12I substitutions and its structural effect upon both the nucleotide base and phosphate of A9. The latter involves the perturbation of a previously identified and well characterized metal ion-binding site known to be catalytically important in both minimal and full-length hammerhead ribozyme sequences. The results permit it to be suggested that G12 plays an important role in stabilizing the active-site structure. This result, although not inconsistent with the potential

Purine and its analogues and radiation damage in Bacillus megaterium spores

Energy Technology Data Exchange (ETDEWEB)

Powers, E.L.

1986-12-01

As an extension of results obtained from radiation studies on caffeine both in other laboratories and more recently in this laboratory using the bacterial spore as the test system, six compounds with chemical structures closely resembling that of caffeine were tested as radiation modifiers. Of these compounds, purine, adenine and hypoxanthine resembled caffeine in sensitizing spores to radiation, while theobromine, xanthine and theophylline did not. These responses are discussed in relation to the electron sequestration hypothesis of cellular sensitization to high-energy radiation.

Overview of CO2 valorization pathways. Final document

International Nuclear Information System (INIS)

Tridant Bel, Jean-Philippe; Pairin, Cecile; Darcet, Cecile; Thybaud, Nathalie; Lebain, David; David, Marc; Morin, Dominique; Bigeon, Philippe; Mansilla, Christine; Amouroux, Jacques; De Witte, Marc; Ungerer, Philippe; Jarrin, Jacques; Blancheton, Jean-Paul; Rene, Francois; Farret, Regis; Gimenez, Michel; Sassi, William; Clin, Francois; Clodic, Denis; Desnost, Carole; Gresser, Robert; Yacono, Charles

2010-06-01

Reducing the emissions of the main anthropogenic greenhouse gases, such as carbon dioxide, is one of the major challenges of this century. The growth in energy demand does not allow, at the present time, the use of fossil fuels to be avoided. As a consequence, carbon capture and storage (CCS) is a solution with great potential and is the subject of many pilot projects. In this field, France is now well positioned, despite a strongly de-carbonated electricity. As a complement to these actions, it is also possible to reuse the CO 2 molecule, considering it as a raw material, as a source of carbon. CO 2 recovery in order to produce chemical compounds is then similar to recycling and would involve an environmental benefit and an economic opportunity at the same time. In this context, the French Agency for Energy and Environment (ADEME) and the French public authorities (MEEDDM, MSR, etc.) asked ALCIMED to better understand the different pathways of CO 2 recycling and to identify the main development opportunities of such technologies in France. The results of the study also relied on the knowledge and experience of a steering committee composed of key figures from the institutional and industrial sectors. A cross-sectional analysis of the literature and telephone interviews with experts (industrial and institutional) conducted to the identification of 12 pathways of carbon dioxide recycling, that have been divided into three segments: the use of CO 2 without processing, chemical processing and biological processing. The technological, economic and environmental factors have been evaluated for each pathway, and key stakeholders and related projects have been complemented. A first analysis has been then conducted in order to compare the different pathways to each other. In addition, ALCIMED and the members of the steering committee of this study have led a first discussion on the position of France in regard to carbon dioxide recycling, putting in light industrial and

Rethink, Rework, Recycle.

Science.gov (United States)

Wrhen, Linda; DiSpezio, Michael A.

1991-01-01

Information about the recycling and reuse of plastics, aluminum, steel, glass, and newspapers is presented. The phases of recycling are described. An activity that allows students to separate recyclable materials is included. The objectives, a list of needed materials, and procedure are provided. (KR)

Poly(alizarin red)/Graphene modified glassy carbon electrode for simultaneous determination of purine and pyrimidine

International Nuclear Information System (INIS)

Ba Xi; Luo Liqiang; Ding Yaping; Zhang Zhen; Chu Yuliang; Wang Bijun; Ouyang Xiaoqian

2012-01-01

Graphical abstract: DPVs of PAR/Graphene/GCE (a) and the bare GCE (c) in 0.1 M PBS containing 50.0 μM G, 50.0 μM A, 100.0 μM T and 100.0 μM C, (b) PAR/Graphene/GCE in 0.1 M PBS. Highlights: ► The sensor exhibited well-separated peaks and low detection limit. ► The sensor possesses high sensitivity and wide linear range. ► The sensor was used for simultaneous detection of G, A, T and C successfully. ► The sensor was applied in a fish sperm DNA sample with satisfactory results. ► The proposed sensor has good stability and reproducibility. - Abstract: In this work, a poly(alizarin red)/Graphene composite film modified glassy carbon electrode (PAR/Graphene/GCE) was prepared for simultaneous determination of four DNA bases (guanine, adenine, thymine and cytosine) without any pretreatment. The morphology and interface property of PAR/Graphene films were examined by scanning electron microscopy and electrochemical impedance spectroscopy. The PAR/Graphene/GCE exhibited excellent electrocatalytic activity toward purine (guanine and adenine) and pyrimidine (thymine and cytosine) in 0.1 M phosphate buffer solution (pH 7.4). Under optimum conditions, differential pulse voltammetry was used to detect the oxidation of purine and pyrimidine. The results showed that PAR/Graphene/GCE exhibited well-separated peaks, low detection limit, high sensitivity and wide linear range for simultaneous detection of purine and pyrimidine. The proposed sensor also has good stability and reproducibility. Furthermore, the modified electrode was applied for the detection of DNA bases in a fish sperm DNA sample with satisfactory results.

Purine and its analogues and radiation damage in Bacillus megaterium spores

International Nuclear Information System (INIS)

Powers, E.L.

1986-01-01

As an extension of results obtained from radiation studies on caffeine both in other laboratories and more recently in this laboratory using the bacterial spore as the test system, six compounds with chemical structures closely resembling that of caffeine were tested as radiation modifiers. Of these compounds, purine, adenine and hypoxanthine resembled caffeine in sensitizing spores to radiation, while theobromine, xanthine and theophylline did not. These responses are discussed in relation to the electron sequestration hypothesis of cellular sensitization to high-energy radiation. (author)

Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

Science.gov (United States)

US Environmental Protection Agency, 2009

2009-01-01

With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

Recycling of electronic scrap

DEFF Research Database (Denmark)

Legarth, Jens Brøbech

This Ph.D. thesis deals with the growingly important field of electronics recycling with special attention to the problem of printed circuit board recycling. A literature survey of contemporary electronics recycling and printed circuit board recycling is presented.Further, an analysis of the role...

Theoretical and experimental studies on the corrosion inhibition potentials of some purines for aluminum in 0.1 M HCl.

Science.gov (United States)

Eddy, Nnabuk O; Momoh-Yahaya, H; Oguzie, Emeka E

2015-03-01

Experimental aspect of the corrosion inhibition potential of adenine (AD), guanine (GU) and, hypoxanthine (HYP) was carried out using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods while the theoretical aspect of the work was carried out by calculations of semi-empirical parameters (for AM1, MNDO, CNDO, PM3 and RM1 Hamiltonians), Fukui functions and inhibitor-metal interaction energies. Results obtained from the experimental studies were in good agreement and indicated that adenine (AD), guanine (GU) and hypoxanthine (HYP) are good adsorption inhibitors for the corrosion of aluminum in solutions of HCl. Data obtained from electrochemical experiment revealed that the studied purines functioned by adsorption on the aluminum/HCl interface and inhibited the cathodic half reaction to a greater extent and anodic half reaction to a lesser extent. The adsorption of the purines on the metal surface was found to be exothermic and spontaneous. Deviation of the adsorption characteristics of the studied purines from the Langmuir adsorption model was compensated by the fitness of Flory Huggins and El Awardy et al. adsorption models. Quantum chemical studies revealed that the experimental inhibition efficiencies of the studied purines are functions of some quantum chemical parameters including total energy of the molecules (TE), energy gap (E L-H), electronic energy of the molecule (EE), dipole moment and core-core repulsion energy (CCR). Fukui functions analysis through DFT and MP2 theories indicated slight complications and unphysical results. However, results obtained from calculated Huckel charges, molecular orbital and interaction energies, the adsorption of the inhibitors proceeded through the imine nitrogen (N5) in GU, emanine nitrogen (N7) in AD and the pyridine nitrogen (N5) in HPY.

Deletion of the distal COOH-terminus of the A2B adenosine receptor switches internalization to an arrestin- and clathrin-independent pathway and inhibits recycling.

Science.gov (United States)

Mundell, S J; Matharu, A-L; Nisar, S; Palmer, T M; Benovic, J L; Kelly, E

2010-02-01

We have investigated the effect of deletions of a postsynaptic density, disc large and zo-1 protein (PDZ) motif at the end of the COOH-terminus of the rat A(2B) adenosine receptor on intracellular trafficking following long-term exposure to the agonist 5'-(N-ethylcarboxamido)-adenosine. The trafficking of the wild type A(2B) adenosine receptor and deletion mutants expressed in Chinese hamster ovary cells was studied using an enzyme-linked immunosorbent assay in combination with immunofluorescence microscopy. The wild type A(2B) adenosine receptor and deletion mutants were all extensively internalized following prolonged treatment with NECA. The intracellular compartment through which the Gln(325)-stop receptor mutant, which lacks the Type II PDZ motif found in the wild type receptor initially trafficked was not the same as the wild type receptor. Expression of dominant negative mutants of arrestin-2, dynamin or Eps-15 inhibited internalization of wild type and Leu(330)-stop receptors, whereas only dominant negative mutant dynamin inhibited agonist-induced internalization of Gln(325)-stop, Ser(326)-stop and Phe(328)-stop receptors. Following internalization, the wild type A(2B) adenosine receptor recycled rapidly to the cell surface, whereas the Gln(325)-stop receptor did not recycle. Deletion of the COOH-terminus of the A(2B) adenosine receptor beyond Leu(330) switches internalization from an arrestin- and clathrin-dependent pathway to one that is dynamin dependent but arrestin and clathrin independent. The presence of a Type II PDZ motif appears to be essential for arrestin- and clathrin-dependent internalization, as well as recycling of the A(2B) adenosine receptor following prolonged agonist addition.

Modelling Recycling Targets

DEFF Research Database (Denmark)

hill, amanda; Leinikka Dall, Ole; Andersen, Frits Møller

2014-01-01

% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...

Recycling production designs: the value of coordination and flexibility in aluminum recycling operations

Science.gov (United States)

Brommer, Tracey H.

The growing motivation for aluminum recycling has prompted interest in recycling alternative and more challenging secondary materials. The nature of these alternative secondary materials necessitates the development of an intermediate recycling facility that can reprocess the secondary materials into a liquid product Two downstream aluminum remelters will incorporate the liquid products into their aluminum alloy production schedules. Energy and environmental benefits result from delivering the products as liquid but coordination challenges persist because of the energy cost to maintain the liquid. Further coordination challenges result from the necessity to establish a long term recycling production plan in the presence of long term downstream aluminum remelter production uncertainty and inherent variation in the daily order schedule of the downstream aluminum remelters. In this context a fundamental question arises, considering the metallurgical complexities of dross reprocessing, what is the value of operating a coordinated set of by-product reprocessing plants and remelting cast houses? A methodology is presented to calculate the optimal recycling center production parameters including 1) the number of recycled products, 2) the volume of recycled products, 3) allocation of recycled materials across recycled products, 4) allocation of recycled products across finished alloys, 4) the level of flexibility for the recycling center to operate. The methods implemented include, 1) an optimization model to describe the long term operations of the recycling center, 2) an uncertainty simulation tool, 3) a simulation optimization method, 4) a dynamic simulation tool with four embedded daily production optimization models of varying degrees of flexibility. This methodology is used to quantify the performance of several recycling center production designs of varying levels of coordination and flexibility. This analysis allowed the identification of the optimal recycling

Concrete produced with recycled aggregates

Directory of Open Access Journals (Sweden)

J. J. L. Tenório

Full Text Available This paper presents the analysis of the mechanical and durable properties of recycled aggregate concrete (RAC for using in concrete. The porosity of recycled coarse aggregates is known to influence the fresh and hardened concrete properties and these properties are related to the specific mass of the recycled coarse aggregates, which directly influences the mechanical properties of the concrete. The recycled aggregates were obtained from construction and demolition wastes (CDW, which were divided into recycled sand (fine and coarse aggregates. Besides this, a recycled coarse aggregate of a specific mass with a greater density was obtained by mixing the recycled aggregates of the CDW with the recycled aggregates of concrete wastes (CW. The concrete was produced in laboratory by combining three water-cement ratios, the ratios were used in agreement with NBR 6118 for structural concretes, with each recycled coarse aggregates and recycled sand or river sand, and the reference concrete was produced with natural aggregates. It was observed that recycled aggregates can be used in concrete with properties for structural concrete. In general, the use of recycled coarse aggregate in combination with recycled sand did not provide good results; but when the less porous was used, or the recycled coarse aggregate of a specific mass with a greater density, the properties of the concrete showed better results. Some RAC reached bigger strengths than the reference concrete.

Green Science: Revisiting Recycling

Science.gov (United States)

Palliser, Janna

2011-01-01

Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling…

CED-10/Rac1 regulates endocytic recycling through the RAB-5 GAP TBC-2.

Directory of Open Access Journals (Sweden)

Lin Sun

Full Text Available Rac1 is a founding member of the Rho-GTPase family and a key regulator of membrane remodeling. In the context of apoptotic cell corpse engulfment, CED-10/Rac1 acts with its bipartite guanine nucleotide exchange factor, CED-5/Dock180-CED-12/ELMO, in an evolutionarily conserved pathway to promote phagocytosis. Here we show that in the context of the Caenorhabditis elegans intestinal epithelium CED-10/Rac1, CED-5/Dock180, and CED-12/ELMO promote basolateral recycling. Furthermore, we show that CED-10 binds to the RAB-5 GTPase activating protein TBC-2, that CED-10 contributes to recruitment of TBC-2 to endosomes, and that recycling cargo is trapped in recycling endosomes in ced-12, ced-10, and tbc-2 mutants. Expression of GTPase defective RAB-5(Q78L also traps recycling cargo. Our results indicate that down-regulation of early endosome regulator RAB-5/Rab5 by a CED-5, CED-12, CED-10, TBC-2 cascade is an important step in the transport of cargo through the basolateral recycling endosome for delivery to the plasma membrane.

Structure and Mechanism of PhnP, a Phosphodiesterase of the Carbon-Phosphorus Lyase Pathway

DEFF Research Database (Denmark)

He, Shu-Mei; Wathier, Matthew; Podzelinska, Kateryna

2011-01-01

PhnP is a phosphodiesterase that plays an important role within the bacterial carbon-phosphorus lyase (CP-lyase) pathway by recycling a "dead-end" intermediate, 5-phospho-α-d-ribosyl 1,2-cyclic phosphate, that is formed during organophosphonate catabolism. As a member of the metallo-β-lactamase s......PhnP is a phosphodiesterase that plays an important role within the bacterial carbon-phosphorus lyase (CP-lyase) pathway by recycling a "dead-end" intermediate, 5-phospho-α-d-ribosyl 1,2-cyclic phosphate, that is formed during organophosphonate catabolism. As a member of the metallo...

Nuclear fuel cycle waste recycling technology deverlopment - Radioactive metal waste recycling technology development

International Nuclear Information System (INIS)

Oh, Won Zin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

1998-08-01

With relation to recycling of the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following were described in this report. 1. Analysis of the state of the art on the radioactive metal waste recycling technologies. 2. Economical assessment on the radioactive metal waste recycling. 3. Process development for radioactive metal waste recycling, A. Decontamination technologies for radioactive metal waste recycling. B. Decontamination waste treatment technologies, C. Residual radioactivity evaluation technologies. (author). 238 refs., 60 tabs., 79 figs

The effect of plane of nutrition on the urinary purine derivative excretion in sheep and goats

International Nuclear Information System (INIS)

Poshiwa, X.; Tigere, A.; Ngongoni, N.T.; Manyuchi, B.; Chakoma, C.

2004-01-01

An experiment was conducted to determine the effect of plane of nutrition on purine derivative excretion and to develop a set of model equations that relate intake to the purine derivative (PD) excretion in sheep and goats. Four male Sabi sheep and four male Small-East African goats (four months old) were used. The trial was a 4 x 4 Latin square cross-over design to examine the response of PD excretion to feed intake. The four diets consisted of star grass (Cynodon nlemfuensis) hay fed ad libitum, and at 85, 70 or 55% of ad libitum. Total PD excretion increased with the increase in feed intake for both sheep and goats. However, the increase did not reach statistical significance (P > 0.05). The model equations relating digestible organic matter intake (X) to PD excretion (Y) were Y = 2.97 X + 0.15 (R 2 =0.72) and Y = 5.86 X - 0.33 (R 2 =0.99) for sheep and goats respectively. (author)

Poly(alizarin red)/Graphene modified glassy carbon electrode for simultaneous determination of purine and pyrimidine

Energy Technology Data Exchange (ETDEWEB)

Ba Xi; Luo Liqiang [Department of Chemistry, Shanghai University, Shanghai 200444 (China); Ding Yaping, E-mail: wdingyp@sina.com [Department of Chemistry, Shanghai University, Shanghai 200444 (China); Zhang Zhen [Department of Chemistry, Shanghai University, Shanghai 200444 (China); Chu Yuliang [Instrumental Analysis and Research Center, Shanghai University, Shanghai 200444 (China); Wang Bijun; Ouyang Xiaoqian [Department of Chemistry, Shanghai University, Shanghai 200444 (China)

2012-11-08

Graphical abstract: DPVs of PAR/Graphene/GCE (a) and the bare GCE (c) in 0.1 M PBS containing 50.0 {mu}M G, 50.0 {mu}M A, 100.0 {mu}M T and 100.0 {mu}M C, (b) PAR/Graphene/GCE in 0.1 M PBS. Highlights: Black-Right-Pointing-Pointer The sensor exhibited well-separated peaks and low detection limit. Black-Right-Pointing-Pointer The sensor possesses high sensitivity and wide linear range. Black-Right-Pointing-Pointer The sensor was used for simultaneous detection of G, A, T and C successfully. Black-Right-Pointing-Pointer The sensor was applied in a fish sperm DNA sample with satisfactory results. Black-Right-Pointing-Pointer The proposed sensor has good stability and reproducibility. - Abstract: In this work, a poly(alizarin red)/Graphene composite film modified glassy carbon electrode (PAR/Graphene/GCE) was prepared for simultaneous determination of four DNA bases (guanine, adenine, thymine and cytosine) without any pretreatment. The morphology and interface property of PAR/Graphene films were examined by scanning electron microscopy and electrochemical impedance spectroscopy. The PAR/Graphene/GCE exhibited excellent electrocatalytic activity toward purine (guanine and adenine) and pyrimidine (thymine and cytosine) in 0.1 M phosphate buffer solution (pH 7.4). Under optimum conditions, differential pulse voltammetry was used to detect the oxidation of purine and pyrimidine. The results showed that PAR/Graphene/GCE exhibited well-separated peaks, low detection limit, high sensitivity and wide linear range for simultaneous detection of purine and pyrimidine. The proposed sensor also has good stability and reproducibility. Furthermore, the modified electrode was applied for the detection of DNA bases in a fish sperm DNA sample with satisfactory results.

GGA3 mediates TrkA endocytic recycling to promote sustained Akt phosphorylation and cell survival

Science.gov (United States)

Li, Xuezhi; Lavigne, Pierre; Lavoie, Christine

2015-01-01

Although TrkA postendocytic sorting significantly influences neuronal cell survival and differentiation, the molecular mechanism underlying TrkA receptor sorting in the recycling or degradation pathways remains poorly understood. Here we demonstrate that Golgi-localized, γ adaptin-ear–containing ADP ribosylation factor-binding protein 3 (GGA3) interacts directly with the TrkA cytoplasmic tail through an internal DXXLL motif and mediates the functional recycling of TrkA to the plasma membrane. We find that GGA3 depletion by siRNA delays TrkA recycling, accelerates TrkA degradation, attenuates sustained NGF-induced Akt activation, and reduces cell survival. We also show that GGA3’s effect on TrkA recycling is dependent on the activation of Arf6. This work identifies GGA3 as a key player in a novel DXXLL-mediated endosomal sorting machinery that targets TrkA to the plasma membrane, where it prolongs the activation of Akt signaling and survival responses. PMID:26446845

Anti-proliferative activity of 2,6-dichloro-9- or 7-(ethoxycarbonylmethyl)-9H- or 7H-purines against several human solid tumour cell lines.

Science.gov (United States)

Morales, Fátima; Ramírez, Alberto; Conejo-García, Ana; Morata, Cynthia; Marchal, Juan A; Campos, Joaquín M

2014-04-09

As leads we took several benzo-fused seven- and six-membered scaffolds linked to the pyrimidine or purine moieties with notable anti-proliferative activity against human breast, colon and melanoma cancerous cell lines. We then decided to maintain the double-ringed nitrogenous bases and change the other components to the ethyl acetate moiety. This way six purine and two 5-fluorouracil derivatives were obtained and evaluated against the MCF-7, HCT-116, A-375 and G-361 cancer cell lines. Two QSARs are obtained between the anti-proliferative IC₅₀ values for compounds 26-33 and the clog P against the melanoma cell lines A-375 and G-361. Our results show that two of the analogues [ethyl 2-(2,6-dichloro-9H- or 7H-purine-9- or 7-yl)acetates (30 and 33, respectively)] are potent cytotoxic agents against all the tumour cell lines assayed, showing single-digit micromolar IC₅₀ values. This exemplifies the potential of our previously reported purine compounds to qualify as lead structures for medicinal chemistry campaigns, affording simplified analogues easy to synthesize and with a noteworthy bioactivity. The selective activity of 30 and 33 against the melanoma cell line A-375, via apoptosis, supposes a great advantage for a future therapeutic use. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Usage of Recycled Pet

Directory of Open Access Journals (Sweden)

A. Ebru Tayyar

2010-01-01

Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

Urinary purine derivatives as a tool to estimate dry matter intake in cattle: a meta-analysis

Science.gov (United States)

The objectives of this study were: 1) to investigate the relationship between dry matter intake (DMI) and urinary purine derivatives (PD) excretion in order to develop equations to predict DMI, and 2) to determine the endogenous excretion of PD for beef and dairy cattle using a meta-analytic approac...

A tiered approach to evaluate an iodine recycling inhibition adverse outcome pathway (AOP) in amphibians

Science.gov (United States)

The enzyme iodotyrosine deiodinase (dehalogenase, IYD) catalyzes iodide recycling and promotes iodide retention in thyroid follicular cells. Loss of function or chemical inhibition of IYD reduces thyroid hormone synthesis, which leads to insufficiency in tissues and subsequent ne...

Assessing changes on poly(ethylene terephthalate) properties after recycling: Mechanical recycling in laboratory versus postconsumer recycled material

Energy Technology Data Exchange (ETDEWEB)

López, María del Mar Castro, E-mail: quimcl02@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Ares Pernas, Ana Isabel, E-mail: aares@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Abad López, Ma José, E-mail: mjabad@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); and others

2014-10-15

Keeping rheological, mechanical and thermal properties of virgin poly(ethylene terephthalate), PET, is necessary to assure the quality of second-market applications. A comparative study of these properties has been undertaken in virgin, mechanical recycled and commercial recycled PET samples. Viscoelastic characterization was carried out by rheological measurements. Mechanical properties were estimated by tensile and Charpy impact strength tests. Thermal properties and crystallinity were evaluated by differential scanning calorimetry and a deconvolution procedure was applied to study the population of the different crystals. Molecular conformational changes related to crystallinity values were studied by FTIR spectroscopy. Variations in average molecular weight were predicted from rheology. Besides, the presence-absence of linear and cyclic oligomeric species was measured by mass spectrometry techniques, as MALDI-TOF. Mechanical recycled PET undergoes a significant decline in rheological, mechanical and thermal properties upon increasing the number of reprocessing steps. This is due to the cleavage of the ester bonds with reduction in molar mass and raise in cyclic oligomeric species, in particular [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G type. Chain shortening plus enrichment in trans conformers favour the crystallization process which occurs earlier and faster with modification in crystal populations. Additional physicochemical steps are necessary to preserve the main benefits of PET. - Highlights: • Combination of multiple techniques to characterize the effects of recycling in PET. • Cleavage of ester bonds reduced viscosity, Mw, toughness in mechanical recycled PET. • Virgin, mechanical recycled and commercial recycled PET differ in crystal populations. • Cyclic oligomers [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G increase from the fourth extrusion cycle onwards.

Dual recycling for GEO 600

International Nuclear Information System (INIS)

Grote, H; Freise, A; Malec, M; Heinzel, G; Willke, B; Lueck, H; Strain, K A; Hough, J; Danzmann, K

2004-01-01

Dual recycling is the combination of signal recycling and power recycling; both optical techniques improve the shot-noise-limited sensitivity of interferometric gravitational-wave detectors. In addition, signal recycling can reduce the loss of light power due to imperfect interference and allows us, in principle, to beat the standard quantum limit. The interferometric gravitational-wave detector GEO 600 is the first of the kilometre-scale detectors to use signal recycling. We have recently equipped the detector with a signal-recycling mirror with a transmittance of 1%. In this paper, we present details of the detector commissioning and the first locks of the dual-recycled interferometer

Protecting groundwater resources at biosolids recycling sites.

Science.gov (United States)

McFarland, Michael J; Kumarasamy, Karthik; Brobst, Robert B; Hais, Alan; Schmitz, Mark D

2013-01-01

In developing the national biosolids recycling rule (Title 40 of the Code of Federal Regulation Part 503 or Part 503), the USEPA conducted deterministic risk assessments whose results indicated that the probability of groundwater impairment associated with biosolids recycling was insignificant. Unfortunately, the computational capabilities available for performing risk assessments of pollutant fate and transport at that time were limited. Using recent advances in USEPA risk assessment methodology, the present study evaluates whether the current national biosolids pollutant limits remain protective of groundwater quality. To take advantage of new risk assessment approaches, a computer-based groundwater risk characterization screening tool (RCST) was developed using USEPA's Multimedia, Multi-pathway, Multi-receptor Exposure and Risk Assessment program. The RCST, which generates a noncarcinogenic human health risk estimate (i.e., hazard quotient [HQ] value), has the ability to conduct screening-level risk characterizations. The regulated heavy metals modeled in this study were As, Cd, Ni, Se, and Zn. Results from RCST application to biosolids recycling sites located in Yakima County, Washington, indicated that biosolids could be recycled at rates as high as 90 Mg ha, with no negative human health effects associated with groundwater consumption. Only under unrealistically high biosolids land application rates were public health risks characterized as significant (HQ ≥ 1.0). For example, by increasing the biosolids application rate and pollutant concentrations to 900 Mg ha and 10 times the regulatory limit, respectively, the HQ values varied from 1.4 (Zn) to 324.0 (Se). Since promulgation of Part 503, no verifiable cases of groundwater contamination by regulated biosolids pollutants have been reported. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Recycling Mentors: an intergenerational, service-learning program to promote recycling and environmental awareness.

Science.gov (United States)

D'abundo, Michelle L; Fugate-Whitlock, Elizabeth I; Fiala, Kelly A

2011-01-01

The purpose of Recycling Mentors was to implement an intergenerational, service-learning program focused on promoting recycling and environmental awareness among students enrolled in Community Health (HEA 301) and Current Issues in Gerontology (GRN 440/540) and adults older than 60 years. Recycling Mentors was conducted in New Hanover County (NHC), North Carolina, where a moderate climate and coastal location attracts many tourists, retirees, and college students. A community like NHC is a good place to implement service-learning that educates both students and older adults about the benefits of recycling to individual health and the environment. During the Fall 2009 semester, undergraduate and graduate students completed institutional review board training and then conducted the program with older adults. The education component of Recycling Mentors included a pre/post survey, brochure, and scheduled visits. Overall, Recycling Mentors was positive service-learning experience with students identifying salient outcomes such as learning about recycling and the environment and working with older adults. In addition, teaching the education component of Recycling Mentors was good practice for students who will be the future health professionals. While service-learning and environmentally themed projects are common, a program that combines the 2 like Recycling Mentors is unique and has the potential to motivate individual change while positively impacting the local community and the environment.

Estimating rumen microbial protein supply for indigenous ruminants using nuclear and purine excretion techniques in Indonesia

International Nuclear Information System (INIS)

Soejono, M.; Yusiati, L.M.; Budhi, S.P.S.; Widyobroto, B.P.; Bachrudin, Z.

1999-01-01

The microbial protein supply to ruminants can be estimated based on the amount of purine derivatives (PD) excreted in the urine. Four experiments were conducted to evaluate the PD excretion method for Bali and Ongole cattle. In the first experiment, six male, two year old Bali cattle (Bos sondaicus) and six Ongole cattle (Bos indicus) of similar sex and age, were used to quantify the endogenous contribution to total PD excretion in the urine. In the second experiment, four cattle from each breed were used to examine the response of PD excretion to feed intake. 14 C-uric acid was injected in one single dose to define the partitioning ratio of renal:non-renal losses of plasma PD. The third experiment was conducted to examine the ratio of purine N:total N in mixed rumen microbial population. The fourth experiment measured the enzyme activities of blood, liver and intestinal tissues concerned with PD metabolism. The results of the first experiment showed that endogenous PD excretion was 145 ± 42.0 and 132 ± 20.0 μmol/kg W 0.75 /d, for Bali and Ongole cattle, respectively. The second experiment indicated that the proportion of plasma PD excreted in the urine of Bali and Ongole cattle was 0.78 and 0.77 respectively. Hence, the prediction of purine absorbed based on PD excretion can be stated as Y = 0.78 X + 0.145 W 0.75 and Y = 0.77 X + 0.132 W 0.75 for Bali and Ongole cattle, respectively. The third experiment showed that there were no differences in the ratio of purine N:total N in mixed rumen microbes of Bali and Ongole cattle (17% vs 18%). The last experiment, showed that intestinal xanthine oxidase activity of Bali cattle was lower than that of Ongole cattle (0.001 vs 0.015 μmol uric acid produced/min/g tissue) but xanthine oxidase activity in the blood and liver of Bali cattle was higher than that of Ongole cattle (3.48 vs 1.34 μmol/min/L plasma and 0.191 vs 0.131 μmol/min/g liver tissue). Thus, there was no difference in PD excretion between these two breeds

Regio- and Enantioselective N-Allylations of Imidazole, Benzimidazole, and Purine Heterocycles Catalyzed by Single-Component Metallacyclic Iridium Complexes

Science.gov (United States)

Stanley, Levi M.

2010-01-01

Highly regio- and enantioselective iridium-catalyzed N-allylations of benzimidazoles, imidazoles, and purines have been developed. N-Allylated benzimidazoles and imidazoles were isolated in high yields (up to 97%) with high branched-to-linear selectivity (up to 99:1) and enantioselectivity (up to 98% ee) from the reactions of benzimidazole and imidazole nucleophiles with unsymmetrical allylic carbonates in the presence of single component, ethylene-bound, metallacyclic iridium catalysts. N-Allylated purines were also obtained in high yields (up to 91%) with high N9:N7 selectivity (up to 96:4), high branched-to-linear selectivity (98:2), and high enantioselectivity (up to 98% ee) under similar conditions. The reactions encompass a range of benzimidazole, imidazole, and purine nucleophiles, as well as a variety of unsymmetrical aryl, heteroaryl, and aliphatic allylic carbonates. Competition experiments between common amine nucleophiles and the heterocyclic nitrogen nucleophiles studied in this work illustrate the effect of nucleophile pKa on the rate of iridium-catalyzed N-allylation reactions. Kinetic studies on the allylation of benzimidazole catalyzed by metallacyclic iridium-phosphoramidite complexes, in combination with studies on the deactivation of these catalysts in the presence of heterocyclic nucleophiles, provide insight into the effects of the structure of the phosphoramidite ligands on the stability of the metallacyclic catalysts. The data obtained from these studies has led to the development of N-allylations of benzimidazoles and imidazoles in the absence of an exogenous base. PMID:19480431

Recycle Alaska: Reduce, Reuse, Recycle. Activities Handbook, Teacher's Guide, and Student Worksheets.

Science.gov (United States)

Alaska State Dept. of Education, Juneau.

Recycling is a very important aspect of conserving the environment for future generations. This guide addresses the topic of litter prevention for the Alaskan environment and contains 42 activities. Activity topics covered include Natural Cycles, Human Interruption of Natural Cycles, Reduce, Reuse, Recycle and Recycled Classroom. Grade level,…

Subcellular location of the enzymes of purine breakdown in the yeast Candida famata grown on uric acid

NARCIS (Netherlands)

Large, Peter J.; Waterham, Hans R.; Veenhuis, Marten

1990-01-01

The subcellular location of the enzymes of purine breakdown in the yeast Candida famata, which grows on uric acid as sole carbon and nitrogen source, has been examined by subcellular fractionation methods. Uricase was confirmed as being peroxisomal, but the other three enzymes, allantoinase,

The Diffusion Effect of MSW Recycling

Directory of Open Access Journals (Sweden)

Yi-Tui Chen

2017-12-01

Full Text Available The purpose of this paper is to compare the recycling performance for some waste fractions selected including food waste, bulk waste, paper, metal products, plastics/rubber and glass products and then to develop some directions for the future improvements. The priority of each waste fraction for recycling is also analyzed by using an importance-performance analysis. Traditionally, the recycling rate that is calculated by the ratio of waste recycled to waste collected is used as an indicator to measure recycling performance. Due to a large variation among waste fractions in municipal solid waste (MSW, the recycling rate cannot reflect the actual recycling performance. The ceiling of recycling rate for each waste fraction estimated from the diffusion models is incorporated into a model to calculate recycling performance. The results show that (1 the diffusion effect exists significantly for the recycling of most recyclables but no evidence is found to support the diffusion effect for the recycling of food waste and bulk waste; (2 the recycling performance of waste metal products ranks the top, compared to waste paper, waste glass and other waste fractions; (3 furthermore, an importance-performance analysis (IPA is employed to analyze the priority of recycling programs and thus this paper suggests that the recycling of food waste should be seen as the most priority item to recycle.

Comparisons of four categories of waste recycling in China’s paper industry based on physical input–output life-cycle assessment model

International Nuclear Information System (INIS)

Liang Sai; Zhang, Tianzhu; Xu Yijian

2012-01-01

Highlights: ► Using crop straws and wood wastes for paper production should be promoted. ► Bagasse and textile waste recycling should be properly limited. ► Imports of scrap paper should be encouraged. ► Sensitivity analysis, uncertainties and policy implications are discussed. - Abstract: Waste recycling for paper production is an important component of waste management. This study constructs a physical input–output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China’s paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for paper production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment.

The regulation of aortic endothelial cells by purines and pyrimidines involves co-existing P2y-purinoceptors and nucleotide receptors linked to phospholipase C.

OpenAIRE

Wilkinson, G. F.; Purkiss, J. R.; Boarder, M. R.

1993-01-01

1. We have examined the phospholipase C responses in bovine aortic endothelial cells to purines (ATP, ADP and analogues) and the pyrimidine, uridine triphosphate (UTP). 2. The cells responded to purines in a manner consistent with the presence of P2y purinoceptors; both 2-methylthioadenosine 5'-triphosphate (2MeSATP) and adenosine 5'-0-(2-thiodiphosphate) (ADP beta S) were potent agonists (EC50 0.41 microM and 0.85 microM respectively) while beta, gamma-methylene ATP at 300 microM was not. 3....

Purine 3':5'-cyclic nucleotides with the nucleobase in a syn orientation: cAMP, cGMP and cIMP.

Science.gov (United States)

Řlepokura, Katarzyna Anna

2016-06-01

Purine 3':5'-cyclic nucleotides are very well known for their role as the secondary messengers in hormone action and cellular signal transduction. Nonetheless, their solid-state conformational details still require investigation. Five crystals containing purine 3':5'-cyclic nucleotides have been obtained and structurally characterized, namely adenosine 3':5'-cyclic phosphate dihydrate, C10H12N5O6P·2H2O or cAMP·2H2O, (I), adenosine 3':5'-cyclic phosphate 0.3-hydrate, C10H12N5O6P·0.3H2O or cAMP·0.3H2O, (II), guanosine 3':5'-cyclic phosphate pentahydrate, C10H12N5O7P·5H2O or cGMP·5H2O, (III), sodium guanosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H11N5O7P(-)·4H2O or Na(cGMP)·4H2O, (IV), and sodium inosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H10N4O7P(-)·4H2O or Na(cIMP)·4H2O, (V). Most of the cyclic nucleotide zwitterions/anions [two from four cAMP present in total in (I) and (II), cGMP in (III), cGMP(-) in (IV) and cIMP(-) in (V)] are syn conformers about the N-glycosidic bond, and this nucleobase arrangement is accompanied by Crib-H...Npur hydrogen bonds (rib = ribose and pur = purine). The base orientation is tuned by the ribose pucker. An analysis of data obtained from the Cambridge Structural Database made in the context of syn-anti conformational preferences has revealed that among the syn conformers of various purine nucleotides, cyclic nucleotides and dinucleotides predominate significantly. The interactions stabilizing the syn conformation have been indicated. The inter-nucleotide contacts in (I)-(V) have been systematized in terms of the chemical groups involved. All five structures display three-dimensional hydrogen-bonded networks.

Synthesis of 9,9′-[1,2-Ethanediylbis(oxymethylene]bis-2-amino-1,9-dihydro-6H-purin-6-one, an Impurity of Acyclovir

Directory of Open Access Journals (Sweden)

Juan José Vaquero

2012-07-01

Full Text Available The synthesis of 9,9'-[1,2-ethanediylbis(oxymethylene]bis-2-amino-1,9-dihydro-6H-purin-6-one, a minor impurity of acyclovir, is described. Starting with commercial N-(9-acetyl-6-oxo-1H-purin-2-ylacetamide, the process uses an acid catalysed phase transfer catalysis (PTC process to produce the selective alkylation at the 9 position of the guanine ring.

Compression Molding of Composite of Recycled HDPE and Recycled Tire Particles

Science.gov (United States)

Liu, Ping; Waskom, Tommy L.; Chen, Zhengyu; Li, Yanze; Peng, Linda

1996-01-01

Plastic and rubber recycling is an effective means of reducing solid waste to the environment and preserving natural resources. A project aimed at developing a new composite material from recycled high density polyethylene (HDPE) and recycled rubber is currently being conducted at Eastern Illinois University. The recycled plastic pellets with recycled rubber particles are extruded into some HDPE/rubber composite strands. The strand can be further cut into pellets that can be used to fabricate other material forms or products. This experiment was inspired by the above-mentioned research activity. In order to measure Durometer hardness of the extruded composite, a specimen with relatively large dimensions was needed. Thus, compression molding was used to form a cylindrical specimen of 1 in. diameter and 1 in. thickness. The initial poor quality of the molded specimen prompted a need to optimize the processing parameters such as temperature, holding time, and pressure. Design of experiment (DOE) was used to obtain optimum combination of the parameters.

Renew or die: The molecular mechanisms of peptidoglycan recycling and antibiotic resistance in Gram-negative pathogens.

Science.gov (United States)

Domínguez-Gil, Teresa; Molina, Rafael; Alcorlo, Martín; Hermoso, Juan A

2016-09-01

Antimicrobial resistance is one of the most serious health threats. Cell-wall remodeling processes are tightly regulated to warrant bacterial survival and in some cases are directly linked to antibiotic resistance. Remodeling produces cell-wall fragments that are recycled but can also act as messengers for bacterial communication, as effector molecules in immune response and as signaling molecules triggering antibiotic resistance. This review is intended to provide state-of-the-art information about the molecular mechanisms governing this process and gather structural information of the different macromolecular machineries involved in peptidoglycan recycling in Gram-negative bacteria. The growing body of literature on the 3D structures of the corresponding macromolecules reveals an extraordinary complexity. Considering the increasing incidence and widespread emergence of Gram-negative multidrug-resistant pathogens in clinics, structural information on the main actors of the recycling process paves the way for designing novel antibiotics disrupting cellular communication in the recycling-resistance pathway. Copyright © 2016. Published by Elsevier Ltd.

PDGF-regulated rab4-dependent recycling of alphavbeta3 integrin from early endosomes is necessary for cell adhesion and spreading.

Science.gov (United States)

Roberts, M; Barry, S; Woods, A; van der Sluijs, P; Norman, J

2001-09-18

It has been postulated that the regulation of integrin vesicular traffic facilitates cell migration by internalizing integrins at the rear of the cell and transporting them forward within vesicles for exocytosis at the leading edge to form new contacts with the extracellular matrix. The rab family of GTPases control key targeting events in the endo/exocytic pathway; therefore, these GTPases may be involved in the regulation of cell-matrix contact assembly. The endo/exocytic cycle of alphavbeta3 and alpha5beta1 integrins was studied using mouse 3T3 fibroblast cell lines. In serum-starved cells, internalized integrins were transported through rab4-positive, early endosomes and arrived at the rab11-positive, perinuclear recycling compartment approximately 30 min after endocytosis. From the recycling compartment, integrins were recycled to the plasma membrane in a rab11-dependent fashion. Following treatment with PDGF, alphavbeta3 integrin, but not alpha5beta1, was rapidly recycled directly back to the plasma membrane from the early endosomes via a rab4-dependent mechanism without the involvement of rab11. This rapid recycling pathway directed alphavbeta3 to numerous small puncta distributed evenly across the dorsal surface of the cell, and the integrin only became localized into focal complexes at later times following PDGF addition. Interestingly, inhibition of PDGF-stimulated alphavbeta3 recycling using dominant-negative rab4 mutants compromised cell adhesion and spreading on vitronectin (a ligand for alphavbeta3), but adhesion to fibronectin (a ligand for alpha5beta1 and alphavbeta3) was unchanged. We propose that growth factor-regulated, rab4-dependent recycling of alphavbeta3 integrin from early endosomes to the plasma membrane is a critical upstream event in the assembly of cell-matrix contacts.

Modulation of the TGF-β1-induced epithelial to mesenchymal transition (EMT) mediated by P1 and P2 purine receptors in MDCK cells.

Science.gov (United States)

Zuccarini, Mariachiara; Giuliani, Patricia; Buccella, Silvana; Di Liberto, Valentina; Mudò, Giuseppa; Belluardo, Natale; Carluccio, Marzia; Rossini, Margherita; Condorelli, Daniele Filippo; Rathbone, Michel Piers; Caciagli, Francesco; Ciccarelli, Renata; Di Iorio, Patrizia

2017-12-01

Epithelial to mesenchymal transition (EMT) occurs during embryogenesis or under pathological conditions such as hypoxia, injury, chronic inflammation, or tissue fibrosis. In renal tubular epithelial cells (MDCK), TGF-β1 induces EMT by reducing or increasing epithelial or mesenchymal marker expression, respectively. In this study, we confirmed that the cAMP analogues, 8-CPT-cAMP or N6-Ph-cAMP, inhibited the TGF-β1-driven overexpression of the mesenchymal markers ZEB-1, Slug, Fibronectin, and α-SMA. Furthermore, we showed that A1, A2A, P2Y1, P2Y11, and P2X7 purine receptor agonists modulated the TGF-β1-induced EMT through the involvement of PKA and/or MAPK/ERK signaling. The stimulation of A2A receptor reduced the overexpression of the EMT-related markers, mainly through the cAMP-dependent PKA pathway, as confirmed by cell pre-treatment with Myr-PKI. Both A1 and P2Y1 receptor stimulation exacerbated the TGF-β1-driven effects, which were reduced by cell pre-treatment with the MAPK inhibitor PD98059, according to the increased ERK1/2 phosphorylation upon receptor activation. The effects induced by P2Y11 receptor activation were oppositely modulated by PKA or MAPK inhibition, in line with the dual nature of the Gs- and Gq-coupled receptor. Differently, P2X7 receptor induced, per se, similar and not additive effects compared to TGF-β1, after prolonged cell exposure to BzATP. These results suggest a putative role of purine receptors as target for anti-fibrotic agents.

Certified Electronics Recyclers

Science.gov (United States)

Learn how EPA encourages all electronics recyclers become certified by demonstrating to an accredited, independent third-party auditor and that they meet specific standards to safely recycle and manage electronics.

Essential pathway identification: from in silico analysis to potential antifungal targets in Aspergillus fumigatus

DEFF Research Database (Denmark)

Thykær, Jette; Andersen, Mikael Rørdam; Baker, S. E.

2009-01-01

with the reactions, we identified orthologous candidate essential genes in Aspergillus fumigatus. Our predictions are validated in part by the modes of action for some antifungal drugs and by molecular genetic studies of essential genes in A. fumigatus and other fungi. The use of metabolic models to predict...... of 1190 biochemically unique reactions that are associated with 871 open reading frames. Through a systematic in silico deletion of single metabolic reactions using this model, several essential metabolic pathways were identified for A. niger. A total of 138 reactions were identified as being essential...... biochemical reactions during growth on a minimal glucose medium. The majority of the reactions grouped into essential biochemical pathways covering cell wall biosynthesis, amino acid biosynthesis, energy metabolism and purine and pyrimidine metabolism. Based on the A. niger open reading frames associated...

An Efficient and Facile Methodology for Bromination of Pyrimidine and Purine Nucleosides with Sodium Monobromoisocyanurate (SMBI

Directory of Open Access Journals (Sweden)

Roger Stromberg

2013-10-01

Full Text Available An efficient and facile strategy has been developed for bromination of nucleosides using sodium monobromoisocyanurate (SMBI. Our methodology demonstrates bromination at the C-5 position of pyrimidine nucleosides and the C-8 position of purine nucleosides. Unprotected and also several protected nucleosides were brominated in moderate to high yields following this procedure.

Cell phone recycling experiences in the United States and potential recycling options in Brazil.

Science.gov (United States)

Silveira, Geraldo T R; Chang, Shoou-Yuh

2010-11-01

This paper presents an overview of cell phone recycling programs currently available in the United States. At the same time, it also provides analyses of the current recycling situation and possible recycling alternatives for Brazil. Although there are several recycling options in the United States, collection rates are still only 10% of all potential devices because customers are not aware of these possibilities. The whole system is financially based on reselling refurbished cell phones and recycled materials to developing countries which represent an effective and strong market. Several recyclers offer funds to collection partners who are either charities or who work with charities while obtaining the materials that they need in order to run their operations. A mobile phone recycling system for Brazil considering the United States experience and the Extended Producer Responsibility (EPR) principle is suggested. A deposit/refund/advance-recycling fee is proposed which might be implemented as a voluntary industrial initiative managed by PRO Brazil, a producer responsibility organization. One widespread public-private agreement will integrate all mobile phone stakeholders, and environmental education actions and promotional events will promote citizen's participation. Copyright © 2010 Elsevier Ltd. All rights reserved.

PET and Recycling

Directory of Open Access Journals (Sweden)

Funda Sevencan

2007-08-01

Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull. 2007; 6(4: 307-312

PET and Recycling

Directory of Open Access Journals (Sweden)

Funda Sevencan

2007-08-01

Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull 2007; 6(4.000: 307-312

Reusing and recycling in Saskatchewan: Environmental benefits of reusing and recycling

Energy Technology Data Exchange (ETDEWEB)

1994-01-01

After an introduction explaining the environmental benefits of reusing and recycling, as well as providing suggestions on minimizing waste and conserving energy, a directory of recyclers and handlers of various kinds of waste in Saskatchewan is presented. Names, addresses/telephone numbers, and types of materials accepted are given for recyclers of animal products, clothing or textiles, glass, compostable materials, industrial hardware, metals, office products, paper, plastic, and tires. Collection depots in the SARCAN recycling program for beverage containers are listed, giving town name, address, hours of operation, and telephone number. Receivers of waste dangerous goods are listed under the categories of ozone-depleting substances, waste batteries, solvents, lubricating oils and oil filters, paint, flammable liquids, antifreeze, drycleaning waste, and miscellaneous.

Recycling of Paper and Cardboard

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Damgaard, Anders

2011-01-01

waste. Recycling of paper and cardboard production waste and postconsumer waste has a long history in the pulp and paper industry. The recycled material now makes up more than half of the raw material used in European pulp and paper industry (ERPC, 2004). This chapter describes briefly how paper...... and cardboard are produced and how waste paper is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of paper recycling....

Water Recycling in Australia

Directory of Open Access Journals (Sweden)

Ross Young

2011-09-01

Full Text Available Australia is the driest inhabited continent on earth and, more importantly, experiences the most variable rainfall of all the continents on our planet. The vast majority of Australians live in large cities on the coast. Because wastewater treatments plants were all located near the coast, it was thought that large scale recycling would be problematic given the cost of infrastructure and pumping required to establish recycled water schemes. This all changed when Australia experienced a decade of record low rainfall and water utilities were given aggressive targets to increase the volume of water recycled. This resulted in recycled water being accepted as a legitimate source of water for non-drinking purposes in a diversified portfolio of water sources to mitigate climate risk. To ensure community support for recycled water, Australia lead the world in developing national guidelines for the various uses of recycled water to ensure the protection of public health and the environment. Australia now provides a great case study of the developments in maximizing water recycling opportunities from policy, regulatory and technological perspectives. This paper explores the evolution in thinking and how approaches to wastewater reuse has changed over the past 40 years from an effluent disposal issue to one of recognizing wastewater as a legitimate and valuable resource. Despite recycled water being a popular choice and being broadly embraced, the concept of indirect potable reuse schemes have lacked community and political support across Australia to date.

Recycling of concrete

International Nuclear Information System (INIS)

Halaszovich, S.

1988-01-01

The paper reviews potentials and problems of disposal or recycling of concrete removed from nuclear installations. Due to the difficulties in determining radioactivity limits that are compatible with utilization of recycled material in practice, a method is proposed that takes into account inhalation of dusts, as occurring during the reprocessing or recycling of the concrete, for instance in road building. This method is based on the maximum permissible radioactivity uptake by inhalation of a nuclide mixture of unknown composition. (RB) [de

Aluminium beverage can recycling

Energy Technology Data Exchange (ETDEWEB)

Lewinski, A von

1985-08-01

Canned beverages have become a controversial issue in this era of ecological sensitivity. METALL has already discussed the problem of can recycling. The present article discusses the technical aspects of aluminium can recycling. Two further articles will follow on aluminium can recycling in North America and on the results of European pilot projects.

Distribution coefficients of purine alkaloids in water-ammonium sulfate-alkyl acetate-dialkyl phthalate systems

Science.gov (United States)

Korenman, Ya. I.; Krivosheeva, O. A.; Mokshina, N. Ya.

2012-12-01

The distribution of purine alkaloids (caffeine, theobromine, theophylline) was studied in the systems: alkyl acetates-dialkyl phtalate-salting-out agent (ammonium sulfate). The quantitative characteristics of the extraction-distribution coefficients ( D) and the degree of extraction ( R, %) are calculated. The relationships between the distribution coefficients of alkaloids and the length of the hydrocarbon radical in the molecule of alkyl acetate (dialkyl phtalate) are determined. The possibility of predicting the distribution coefficients is demonstrated.

The Fernald Waste Recycling Program

International Nuclear Information System (INIS)

Motl, G.P.

1993-01-01

Recycling is considered a critical component of the waste disposition strategy at the Fernald Plant. It is estimated that 33 million cubic feet of waste will be generated during the Fernald cleanup. Recycling some portion of this waste will not only conserve natural resources and disposal volume but will, even more significantly, support the preservation of existing disposition options such as off-site disposal or on-site storage. Recognizing the strategic implications of recycling, this paper outlines the criteria used at Fernald to make recycle decisions and highlights several of Fernald's current recycling initiatives

Enteric Glia Mediate Neuron Death in Colitis Through Purinergic Pathways That Require Connexin-43 and Nitric OxideSummary

Directory of Open Access Journals (Sweden)

Isola A.M. Brown

2016-01-01

Full Text Available Background & Aims: The concept of enteric glia as regulators of intestinal homeostasis is slowly gaining acceptance as a central concept in neurogastroenterology. Yet how glia contribute to intestinal disease is still poorly understood. Purines generated during inflammation drive enteric neuron death by activating neuronal P2X7 purine receptors (P2X7R; triggering adenosine triphosphate (ATP release via neuronal pannexin-1 channels that subsequently recruits intracellular calcium ([Ca2+]i in surrounding enteric glia. We tested the hypothesis that the activation of enteric glia contributes to neuron death during inflammation. Methods: We studied neuroinflammation in vivo using the 2,4-dinitrobenzene sulfonic acid model of colitis and in situ using whole-mount preparations of human and mouse intestine. Transgenic mice with a targeted deletion of glial connexin-43 (Cx43 [GFAP::CreERT2+/−/Cx43f/f] were used to specifically disrupt glial signaling pathways. Mice deficient in inducible nitric oxide (NO synthase (iNOS−/− were used to study NO production. Protein expression and oxidative stress were measured using immunohistochemistry and in situ Ca2+ and NO imaging were used to monitor glial [Ca2+]i and [NO]i. Results: Purinergic activation of enteric glia drove [Ca2+]i responses and enteric neuron death through a Cx43-dependent mechanism. Neurotoxic Cx43 activity, driven by NO production from glial iNOS, was required for neuron death. Glial Cx43 opening liberated ATP and Cx43-dependent ATP release was potentiated by NO. Conclusions: Our results show that the activation of glial cells in the context of neuroinflammation kills enteric neurons. Mediators of inflammation that include ATP and NO activate neurotoxic pathways that converge on glial Cx43 hemichannels. The glial response to inflammatory mediators might contribute to the development of motility disorders. Keywords: Enteric Nervous System, Hemichannels

The recycling is moving

CERN Multimedia

GS Department

2011-01-01

The recycling site currently situated near building 133 has been transferred to the car park of building 156. The site is identified by the sign “RECYCLING” and the above logo. In this new, more accessible site, you will find recycling bins for the following waste: PET (recyclable plastic bottles); Aluminium cans; Nespresso coffee capsules.  

Purine Metabolism in Acute Cerebral Ischemia

Directory of Open Access Journals (Sweden)

Ye. V. Oreshnikov

2008-01-01

Full Text Available Objective: to study the specific features of purine metabolism in clinically significant acute cerebral ischemia. Subjects and materials. Three hundred and fifty patients with the acutest cerebral ischemic stroke were examined. The parameters of gas and electrolyte composition, acid-base balance, the levels of malonic dialdehyde, adenine, guanine, hypox-anthine, xanthine, and uric acid, and the activity of xanthine oxidase were determined in arterial and venous bloods and spinal fluid. Results. In ischemic stroke, hyperuricemia reflects the severity of cerebral metabolic disturbances, hemodynamic instability, hypercoagulation susceptiility, and the extent of neurological deficit. In ischemic stroke, hyperuri-corachia is accompanied by the higher spinal fluid levels of adenine, guanine, hypoxanthine, and xanthine and it is an indirect indicator of respiratory disorders of central genesis, systemic acidosis, hypercoagulation susceptibility, free radical oxidation activation, the intensity of a stressor response to cerebral ischemia, cerebral metabolic disturbances, the depth of reduced consciousness, and the severity of neurological deficit. Conclusion. The high venous blood activity of xanthine oxidase in ischemic stroke is associated with the better neurological parameters in all follow-up periods, the better early functional outcome, and lower mortality rates. Key words: hyperuricemia, stroke, xanthine oxidase, uric acid, cerebral ischemia.

Intrinsic Apoptosis Pathway in Fallopian Tube Epithelial Cells Induced by Cladribine

Directory of Open Access Journals (Sweden)

Ewelina Wawryk-Gawda

2014-01-01

Full Text Available Cladribine is a purine nucleoside analog which initiates the apoptotic mechanism within cells. Moreover, the available data confirms that cladribine, with the participation of the p53 protein, as well as the proapoptotic proteins from the Bcl-2 family, also induces the activation of the intrinsic apoptosis pathway. However, while there has been a lot of research devoted to the effect of cladribine on lymphatic system cells, little is known about the impact of cladribine on the reproductive system. The aim of our study was to evaluate apoptosis in oviduct epithelial cells sourced from 15 different female rats. In so doing, the sections were stained with caspases 3, 9, and 8. Results suggest that cladribine also induces apoptosis in the oviduct epithelial cells by way of the intrinsic pathway. Indeed, the discontinuing of the administration of cladribine leads to a reduction in the amount of apoptotic cells in the oviduct epithelium.

Tire Recycling

Science.gov (United States)

1997-01-01

Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

The functional interplay of Rab11, FIP3 and Rho proteins on the endosomal recycling pathway controls cell shape and symmetry.

Science.gov (United States)

Bouchet, Jérôme; McCaffrey, Mary W; Graziani, Andrea; Alcover, Andrés

2018-07-04

Several families of small GTPases regulate a variety of fundamental cellular processes, encompassing growth factor signal transduction, vesicular trafficking and control of the cytoskeleton. Frequently, their action is hierarchical and complementary, but much of the detail of their functional interactions remains to be clarified. It is well established that Rab family members regulate a variety of intracellular vesicle trafficking pathways. Moreover, Rho family GTPases are pivotal for the control of the actin and microtubule cytoskeleton. However, the interplay between these 2 types of GTPases has been rarely reported. We discuss here our recent findings showing that Rab11, a key regulator of endosomal recycling, and Rac1, a central actin cytoskeleton regulator involved in lamellipodium formation and cell migration, interplay on endosomes through the Rab11 effector FIP3. In the context of the rapidly reactive T lymphocytes, Rab11-Rac1 endosomal functional interplay is important to control cell shape changes and cell symmetry during lymphocyte spreading and immunological synapse formation and ultimately modulate T cell activation.

Recycle Glass in Foam Glass Production

DEFF Research Database (Denmark)

Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

Study of copper and purine-copper complexes on modified carbon electrodes by cyclic and elimination voltammetry

Czech Academy of Sciences Publication Activity Database

Trnková, L.; Zerzánková, L.; Dyčka, F.; Mikelová, R.; Jelen, František

2008-01-01

Roč. 8, č. 1 (2008), s. 429-444 ISSN 1424-8220 R&D Projects: GA AV ČR(CZ) IAA100040602; GA AV ČR(CZ) IAA400040804 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : copper-purine complexes * paraffin-impregnated graphite electrode * mercury-film electrode Subject RIV: BO - Biophysics Impact factor: 1.870, year: 2008

Auditing an intensive care unit recycling program.

Science.gov (United States)

Kubicki, Mark A; McGain, Forbes; O'Shea, Catherine J; Bates, Samantha

2015-06-01

The provision of health care has significant direct environmental effects such as energy and water use and waste production, and indirect effects, including manufacturing and transport of drugs and equipment. Recycling of hospital waste is one strategy to reduce waste disposed of as landfill, preserve resources, reduce greenhouse gas emissions, and potentially remain fiscally responsible. We began an intensive care unit recycling program, because a significant proportion of ICU waste was known to be recyclable. To determine the weight and proportion of ICU waste recycled, the proportion of incorrect waste disposal (including infectious waste contamination), the opportunity for further recycling and the financial effects of the recycling program. We weighed all waste and recyclables from an 11-bed ICU in an Australian metropolitan hospital for 7 non-consecutive days. As part of routine care, ICU waste was separated into general, infectious and recycling streams. Recycling streams were paper and cardboard, three plastics streams (polypropylene, mixed plastics and polyvinylchloride [PVC]) and commingled waste (steel, aluminium and some plastics). ICU waste from the waste and recycling bins was sorted into those five recycling streams, general waste and infectious waste. After sorting, the waste was weighed and examined. Recycling was classified as achieved (actual), potential and total. Potential recycling was defined as being acceptable to hospital protocol and local recycling programs. Direct and indirect financial costs, excluding labour, were examined. During the 7-day period, the total ICU waste was 505 kg: general waste, 222 kg (44%); infectious waste, 138 kg (27%); potentially recyclable waste, 145 kg (28%). Of the potentially recyclable waste, 70 kg (49%) was actually recycled (14% of the total ICU waste). In the infectious waste bins, 82% was truly infectious. There was no infectious contamination of the recycling streams. The PVC waste was 37% contaminated

Oligomeric interface modulation causes misregulation of purine 5'-nucleotidase in relapsed leukemia

Czech Academy of Sciences Publication Activity Database

Hnízda, Aleš; Škerlová, Jana; Fábry, Milan; Pachl, Petr; Šinalová, Martina; Vrzal, Lukáš; Man, Petr; Novák, Petr; Řezáčová, Pavlína; Veverka, Václav

2016-01-01

Roč. 14, Oct 19 (2016), č. článku 91. ISSN 1741-7007 R&D Projects: GA ČR GA15-06582S; GA MŠk(CZ) LK11205; GA MŠk(CZ) LO1304; GA MŠk LO1302; GA MŠk(CZ) LD15089; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388963 ; RVO:68378050 ; RVO:61388971 Keywords : nucleotidase * cancer mutations * relapsed ALL * purine metabolism * allosteric regulation Subject RIV: CE - Biochemistry; EE - Microbiology, Virology (MBU-M) Impact factor: 6.779, year: 2016 http://bmcbiol.biomedcentral.com/articles/10.1186/s12915-016-0313-y

Purine-related metabolites and their converting enzymes are altered in frontal, parietal and temporal cortex at early stages of Alzheimer's disease pathology.

Science.gov (United States)

Alonso-Andrés, Patricia; Albasanz, José Luis; Ferrer, Isidro; Martín, Mairena

2018-01-24

Adenosine, hypoxanthine, xanthine, guanosine and inosine levels were assessed by HPLC, and the activity of related enzymes 5'-nucleotidase (5'-NT), adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) measured in frontal (FC), parietal (PC) and temporal (TC) cortices at different stages of disease progression in Alzheimer's disease (AD) and in age-matched controls. Significantly decreased levels of adenosine, guanosine, hypoxanthine and xanthine, and apparently less inosine, are found in FC from the early stages of AD; PC and TC show an opposing pattern, as adenosine, guanosine and inosine are significantly increased at least at determinate stages of AD whereas hypoxanthine and xanthine levels remain unaltered. 5'-NT is reduced in membranes and cytosol in FC mainly at early stages but not in PC, and only at advanced stages in cytosol in TC. ADA activity is decreased in AD when considered as a whole but increased at early stages in TC. Finally, PNP activity is increased only in TC at early stages. Purine metabolism alterations occur at early stages of AD independently of neurofibrillary tangles and β-amyloid plaques. Alterations are stage dependent and region dependent, the latter showing opposite patterns in FC compared with PC and TC. Adenosine is the most affected of the assessed purines. © 2018 International Society of Neuropathology.

Recycling of Metals

DEFF Research Database (Denmark)

Damgaard, Anders; Christensen, Thomas Højlund

2011-01-01

Metals like iron and aluminium are produced from mineral ore and used for a range of products, some of which have very short lifetimes and thus constitute a major fraction of municipal waste. Packaging in terms of cans, foils and containers are products with a short lifetime. Other products like...... appliances, vehicles and buildings, containing iron and aluminium metals, have long lifetimes before they end up in the waste stream. The recycling of production waste and postconsumer metals has a long history in the metal industry. Some metal smelters are today entirely based on scarp metals. This chapter...... describes briefly how iron and aluminium are produced and how scrap metal is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of metal recycling. Copper and other metals are also found in waste but in much smaller...

Nuclear reactor recyclation device

International Nuclear Information System (INIS)

Takigawa, Yukio; Chuma, Kazuto

1987-01-01

Purpose: To prevent the unevenness for the coolant flow rate even when abnormality occurs to one of recycling pumps. Constitution: A plurality of jet pumps disposed at an interval around the reactor core are divided circumferentially into two sets, and a pipeway is disposed to the outside of each pair including recycling pumps corresponding to each of the sets. The pipeway is connected to the recycling inlet of the jet pump by way of a manifold. The discharge portion of the recycling pumps of the loop pipeway are connected with each other by way of communication pipes, and a normally closed valve is disposed to the communication pipe and the normally closed valve of the communication pipe is opened upon detecting abnormality for one of the recycling pumps. Thus, if either one of the pair of recycling pumps shows abnormal state, coolants flows from the other of pipeway to the outside of the loop pipeway and coolants are supplied from all the jet pumps to the reactor core portion and, accordingly, the not-uniform flow rate can be prevented to eliminate undesired effect on the reactor core. (Kamimura, M.)

Recycling - Danish Waste Management Strategy

DEFF Research Database (Denmark)

Romann, Anne Funch; Thøgersen, John; Husmer, Lis

The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials.......The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials....

Length sensing and control of a Michelson interferometer with power recycling and twin signal recycling cavities.

Science.gov (United States)

Gräf, Christian; Thüring, André; Vahlbruch, Henning; Danzmann, Karsten; Schnabel, Roman

2013-03-11

The techniques of power recycling and signal recycling have proven as key concepts to increase the sensitivity of large-scale gravitational wave detectors by independent resonant enhancement of light power and signal sidebands within the interferometer. Developing the latter concept further, twin signal recycling was proposed as an alternative to conventional detuned signal recycling. Twin signal recycling features the narrow-band sensitivity gain of conventional detuned signal recycling but furthermore facilitates the injection of squeezed states of light, increases the detector sensitivity over a wide frequency band and requires a less complex detection scheme for optimal signal readout. These benefits come at the expense of an additional recycling mirror, thus increasing the number of degrees of freedom in the interferometer which need to be controlled.In this article we describe the development of a length sensing and control scheme and its successful application to a tabletop-scale power recycled Michelson interferometer with twin signal recycling. We were able to lock the interferometer in all relevant longitudinal degrees of freedom and thus laid the foundation for further investigations of this interferometer configuration to evaluate its viability for the application in gravitational wave detectors.

Validation of dose calculation programmes for recycling

International Nuclear Information System (INIS)

Menon, Shankar; Brun-Yaba, Christine; Yu, Charley; Cheng, Jing-Jy; Williams, Alexander

2002-12-01

This report contains the results from an international project initiated by the SSI in 1999. The primary purpose of the project was to validate some of the computer codes that are used to estimate radiation doses due to the recycling of scrap metal. The secondary purpose of the validation project was to give a quantification of the level of conservatism in clearance levels based on these codes. Specifically, the computer codes RESRAD-RECYCLE and CERISE were used to calculate radiation doses to individuals during the processing of slightly contaminated material, mainly in Studsvik, Sweden. Calculated external doses were compared with measured data from different steps of the process. The comparison of calculations and measurements shows that the computer code calculations resulted in both overestimations and underestimations of the external doses for different recycling activities. The SSI draws the conclusion that the accuracy is within one order of magnitude when experienced modellers use their programmes to calculate external radiation doses for a recycling process involving material that is mainly contaminated with cobalt-60. No errors in the codes themselves were found. Instead, the inaccuracy seems to depend mainly on the choice of some modelling parameters related to the receptor (e.g., distance, time, etc.) and simplifications made to facilitate modelling with the codes (e.g., object geometry). Clearance levels are often based on studies on enveloping scenarios that are designed to cover all realistic exposure pathways. It is obvious that for most practical cases, this gives a margin to the individual dose constraint (in the order of 10 micro sievert per year within the EC). This may be accentuated by the use of conservative assumptions when modelling the enveloping scenarios. Since there can obviously be a fairly large inaccuracy in the calculations, it seems reasonable to consider some degree of conservatism when establishing clearance levels based on

Validation of dose calculation programmes for recycling

Energy Technology Data Exchange (ETDEWEB)

Menon, Shankar [Menon Consulting, Nykoeping (Sweden); Brun-Yaba, Christine [Inst. de Radioprotection et Securite Nucleaire (France); Yu, Charley; Cheng, Jing-Jy [Argonne National Laboratory, IL (United States). Environmental Assessment Div.; Bjerler, Jan [Studsvik Stensand, Nykoeping (Sweden); Williams, Alexander [Dept. of Energy (United States). Office of Environmental Management

2002-12-01

This report contains the results from an international project initiated by the SSI in 1999. The primary purpose of the project was to validate some of the computer codes that are used to estimate radiation doses due to the recycling of scrap metal. The secondary purpose of the validation project was to give a quantification of the level of conservatism in clearance levels based on these codes. Specifically, the computer codes RESRAD-RECYCLE and CERISE were used to calculate radiation doses to individuals during the processing of slightly contaminated material, mainly in Studsvik, Sweden. Calculated external doses were compared with measured data from different steps of the process. The comparison of calculations and measurements shows that the computer code calculations resulted in both overestimations and underestimations of the external doses for different recycling activities. The SSI draws the conclusion that the accuracy is within one order of magnitude when experienced modellers use their programmes to calculate external radiation doses for a recycling process involving material that is mainly contaminated with cobalt-60. No errors in the codes themselves were found. Instead, the inaccuracy seems to depend mainly on the choice of some modelling parameters related to the receptor (e.g., distance, time, etc.) and simplifications made to facilitate modelling with the codes (e.g., object geometry). Clearance levels are often based on studies on enveloping scenarios that are designed to cover all realistic exposure pathways. It is obvious that for most practical cases, this gives a margin to the individual dose constraint (in the order of 10 micro sievert per year within the EC). This may be accentuated by the use of conservative assumptions when modelling the enveloping scenarios. Since there can obviously be a fairly large inaccuracy in the calculations, it seems reasonable to consider some degree of conservatism when establishing clearance levels based on

The optimized microwave-assisted decomposition of formamides and its synthetic utility in the amination reactions of purines

Czech Academy of Sciences Publication Activity Database

Čechová, Lucie; Jansa, Petr; Šála, Michal; Dračínský, Martin; Holý, Antonín; Janeba, Zlatko

2011-01-01

Roč. 67, č. 5 (2011), s. 866-871 ISSN 0040-4020 R&D Projects: GA MŠk 1M0508; GA AV ČR KJB400550903 Institutional research plan: CEZ:AV0Z40550506 Keywords : microwave-assisted synthesis * DMF * formamides * dehalogenative amination * purines Subject RIV: CC - Organic Chemistry Impact factor: 3.025, year: 2011

Nuclear recycling: costs, savings, and safeguards

International Nuclear Information System (INIS)

Spinrad, B.I.

1985-01-01

This chapter discusses the economics, physical and chemical processes, and safety of nuclear fuel recycling. The spent fuel must be chemically reprocessed in order to recover uranium and plutonium. Topics considered include indifference costs, recycling in light water reactors (LWRs), plutonium in fast reactors, the choice between recycling and storage, safeguards, and weapons proliferation. It is shown that the economics of recycling nuclear fuel involves the actual costs and savings of the recycling operation in terms of money spent, made, and saved, and the impact of the recycling on the future cost of uranium

Modeling compositional dynamics based on GC and purine contents of protein-coding sequences

KAUST Repository

Zhang, Zhang

2010-11-08

Background: Understanding the compositional dynamics of genomes and their coding sequences is of great significance in gaining clues into molecular evolution and a large number of publically-available genome sequences have allowed us to quantitatively predict deviations of empirical data from their theoretical counterparts. However, the quantification of theoretical compositional variations for a wide diversity of genomes remains a major challenge.Results: To model the compositional dynamics of protein-coding sequences, we propose two simple models that take into account both mutation and selection effects, which act differently at the three codon positions, and use both GC and purine contents as compositional parameters. The two models concern the theoretical composition of nucleotides, codons, and amino acids, with no prerequisite of homologous sequences or their alignments. We evaluated the two models by quantifying theoretical compositions of a large collection of protein-coding sequences (including 46 of Archaea, 686 of Bacteria, and 826 of Eukarya), yielding consistent theoretical compositions across all the collected sequences.Conclusions: We show that the compositions of nucleotides, codons, and amino acids are largely determined by both GC and purine contents and suggest that deviations of the observed from the expected compositions may reflect compositional signatures that arise from a complex interplay between mutation and selection via DNA replication and repair mechanisms.Reviewers: This article was reviewed by Zhaolei Zhang (nominated by Mark Gerstein), Guruprasad Ananda (nominated by Kateryna Makova), and Daniel Haft. 2010 Zhang and Yu; licensee BioMed Central Ltd.

Modeling compositional dynamics based on GC and purine contents of protein-coding sequences

KAUST Repository

Zhang, Zhang; Yu, Jun

2010-01-01

Background: Understanding the compositional dynamics of genomes and their coding sequences is of great significance in gaining clues into molecular evolution and a large number of publically-available genome sequences have allowed us to quantitatively predict deviations of empirical data from their theoretical counterparts. However, the quantification of theoretical compositional variations for a wide diversity of genomes remains a major challenge.Results: To model the compositional dynamics of protein-coding sequences, we propose two simple models that take into account both mutation and selection effects, which act differently at the three codon positions, and use both GC and purine contents as compositional parameters. The two models concern the theoretical composition of nucleotides, codons, and amino acids, with no prerequisite of homologous sequences or their alignments. We evaluated the two models by quantifying theoretical compositions of a large collection of protein-coding sequences (including 46 of Archaea, 686 of Bacteria, and 826 of Eukarya), yielding consistent theoretical compositions across all the collected sequences.Conclusions: We show that the compositions of nucleotides, codons, and amino acids are largely determined by both GC and purine contents and suggest that deviations of the observed from the expected compositions may reflect compositional signatures that arise from a complex interplay between mutation and selection via DNA replication and repair mechanisms.Reviewers: This article was reviewed by Zhaolei Zhang (nominated by Mark Gerstein), Guruprasad Ananda (nominated by Kateryna Makova), and Daniel Haft. 2010 Zhang and Yu; licensee BioMed Central Ltd.

Benchmarking survey for recycling.

Energy Technology Data Exchange (ETDEWEB)

Marley, Margie Charlotte; Mizner, Jack Harry

2005-06-01

This report describes the methodology, analysis and conclusions of a comparison survey of recycling programs at ten Department of Energy sites including Sandia National Laboratories/New Mexico (SNL/NM). The goal of the survey was to compare SNL/NM's recycling performance with that of other federal facilities, and to identify activities and programs that could be implemented at SNL/NM to improve recycling performance.

A tale of five cities: Using recycling frameworks to analyse inclusive recycling performance.

Science.gov (United States)

Scheinberg, Anne; Simpson, Michael

2015-11-01

'Recycling' is a source of much confusion, particularly when comparing solid waste systems in high-income countries with those in low- and middle-income countries. Few analysts can explain why the performance and structure of recycling appears to be so different in rich countries from poor ones, nor why well-meaning efforts to implement recycling so often fail. The analysis of policy drivers, and the Integrated Sustainable Waste Management (ISWM) framework, come close to an explanation.This article builds on these earlier works, focusing in on five cities profiled in the 2010 UN-Habitat publication (Scheinberg A, Wilson DC and Rodic L (2010) Solid Waste Management in the World's Cities. UN-Habitat's Third Global Report on the State of Water and Sanitation in the World's Cities. Newcastle-on-Tyne, UK: Earthscan Publications). Data from these cities and others provides the basis for developing a new tool to analyse inclusive recycling performance. The points of departure are the institutional and economic relationships between the service chain, the public obligation to remove waste, pollution, and other forms of disvalue, and the value chain, a system of private enterprises trading valuable materials and providing markets for recyclables. The methodological innovation is to use flows of materials and money as indicators of institutional relationships, and is an extension of process flow diagramming.The authors are using the term 'recycling framework analysis' to describe this new form of institutional analysis. The diagrams increase our understanding of the factors that contribute to high-performance inclusive recycling. By focusing on institutional relationships, the article seeks to improve analysis, planning, and ultimately, outcomes, of recycling interventions. © The Author(s) 2015.

Resource Efficient Metal and Material Recycling

Science.gov (United States)

Reuter, Markus A.; van Schaik, Antoinette

Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

[Separation of purines, pyrimidines, pterins and flavonoids on magnolol-bonded silica gel stationary phase by high performance liquid chromatography].

Science.gov (United States)

Chen, Hong; Li, Laishen; Zhang, Yang; Zhou, Rendan

2012-10-01

A new magnolol-bonded silica gel stationary phase (MSP) was used to separate the basic drugs including four purines, eight pyrimidines, four pterins and five flavonoids as polar representative samples by high performance liquid chromatography (HPLC). To clarify the separation mechanism, a commercial ODS column was also tested under the same chromatographic conditions. The high selectivities and fast baseline separations of the above drugs were achieved by using simple mobile phases on MSP. Although there is no end-caped treatment, the peak shapes of basic drugs containing nitrogen such as purines, pyrimidines and pterins were rather symmetrical on MSP, which indicated the the magnolol as ligand with multi-sites could shield the side effect of residual silanol groups on the surface of silica gel. Although somewhat different in the separation resolution, it was found that the elution orders of some drugs were generally similar on both MSP and ODS. The hydrophobic interaction should play a significant role in the separations of the above basic drugs, which was attributed to their reversed-phase property in the nature. However, MSP could provide the additional sites for many polar solutes, which was a rational explanation for the high selectivity of MSP. For example, in the separation of purines, pyrimidines and pterins on MSP, hydrogen-bonding and dipole-dipole interactions played leading roles besides hydrophobic interaction. Some solute molecules (such as mercaptopurine, vitexicarpin) and MSP can form the strong pi-pi stacking in the separation process. All enhanced the retention and improved the separation selectivity of MSP, which facilitated the separation of the basic drugs.

Printability of papers recycled from toner and inkjet-printed papers after deinking and recycling processes.

Science.gov (United States)

Karademir, Arif; Aydemir, Cem; Tutak, Dogan; Aravamuthan, Raja

2018-04-01

In our contemporary world, while part of the fibers used in the paper industry is obtained from primary fibers such as wood and agricultural plants, the rest is obtained from secondary fibers from waste papers. To manufacture paper with high optical quality from fibers of recycled waste papers, these papers require deinking and bleaching of fibers at desired levels. High efficiency in removal of ink from paper mass during recycling, and hence deinkability, are especially crucial for the optical and printability quality of the ultimate manufactured paper. In the present study, deinkability and printability performance of digitally printed paper with toner or inkjet ink were compared for the postrecycling product. To that end, opaque 80 g/m 2 office paper was digitally printed under standard printing conditions with laser toner or inkjet ink; then these sheets of paper were deinked by a deinking process based on the INGEDE method 11 p. After the deinking operation, the optical properties of the obtained recycled handsheets were compared with unprinted (reference) paper. Then the recycled paper was printed on once again under the same conditions as before with inkjet and laser printers, to monitor and measure printing color change before and after recycling, and differences in color universe. Recycling and printing performances of water-based inkjet and toner-based laser printed paper were obtained. The outcomes for laser-printed recycled paper were better than those for inkjet-printed recycled paper. Compared for luminosity Y, brightness, CIE a* and CIE b* values, paper recycled from laser-printed paper exhibited higher value than paper recycled from inkjet-printed paper.

Recycling of Glass

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Damgaard, Anders

2011-01-01

Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

Internalization and recycling of receptor-bound gonadotropin-releasing hormone agonist in pituitary gonadotropes

International Nuclear Information System (INIS)

Schvartz, I.; Hazum, E.

1987-01-01

The fate of cell surface gonadotropin-releasing hormone (GnRH) receptors on pituitary cells was studied utilizing lysosomotropic agents and monensin. Labeling of pituitary cells with a photoreactive GnRH derivative, [azidobenzoyl-D-Lys6]GnRH, revealed a specific band of Mr = 60,000. When photoaffinity-labeled cells were exposed to trypsin immediately after completion of the binding, the radioactivity incorporated into the Mr = 60,000 band decreased, with a concomitant appearance of a proteolytic fragment (Mr = 45,000). This fragment reflects cell surface receptors. Following GnRH binding, the hormone-receptor complexes underwent internalization, partial degradation, and recycling. The process of hormone-receptor complex degradation was substantially prevented by lysosomotropic agents, such as chloroquine and methylamine, or the proton ionophore, monensin. Chloroquine and monensin, however, did not affect receptor recycling, since the tryptic fragment of Mr = 45,000 was evident after treatment with these agents. This suggests that recycling of GnRH receptors in gonadotropes occurs whether or not the internal environment is acidic. Based on these findings, we propose a model describing the intracellular pathway of GnRH receptors

You're a "What"? Recycling Coordinator

Science.gov (United States)

Torpey, Elka Maria

2011-01-01

Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

WATER RESISTANCE OF RECYCLED PAPER PANEL

Directory of Open Access Journals (Sweden)

Alexander Rani Suryandono

2017-06-01

Alice Wisler (2015 Facts about Recycling Paper. http://greenliving.lovetoknow.com/Facts_About_Recycling_Paper. Accessed 2 April 2016 Clay Miller (2011 5 Benefits of Recycling Paper. http://www.ways2gogreenblog.com/2011/09/28/5-benefits-of-recycling-paper/. Accessed 10 May 2016 Hari Goyal (2015 Grades of Paper. http://www.paperonweb.com/grade.htm. Accessed 2 April 2016 Hari Goyal (2015 Properties of Paper. http://www.paperonweb.com/paperpro.htm. Accessed 2 April 2016 Kathryn Sukalich (2016 Everything You Need to Know about Paper Recycling. http://earth911.com/business-policy/business/paper-recycling-details-basics/. Accessed 15 July 2016 [U1] Larry West (2015 Why Recycle Paper. http://environment.about.com/od/recycling/a/The-Benefits-Of-Paper-Recycling-Why-Recycle-Paper.htm. Accesed 15 June 2016 Marie-Luise Blue (2008 The Advantages of Recycling Paper. http://education.seattlepi.com/advantages-recycling-paper-3440.html. Accessed 15 June 2016 Nina Spitzer (2009 http://www.sheknows.com/home-and-gardening/articles/810025/the-impact-of-disposable-coffee-cups-on-the-environment. Accessed 15 June 2016 Radio New Zealand (2010 Iwi not Giving Up Fight against Tasman Mill Discharges. http://www.radionz.co.nz/news/regional/64521/iwi-not-giving-up-fight-against-tasman-mill-discharges. Accessed 15 July 2016 Rick LeBlanc (2016 Paper Recycling Facts, Figures and Information Sources. https://www.thebalance.com/paper-recycling-facts-figures-and-information-sources-2877868?_ga=1.192832942.544061388.1477446686. Accesed 2 April 2016 Robinson Meyer (2016 Will More Newspapers Go Nonprofit? http://www.theatlantic.com/technology/archive/2016/01/newspapers-philadelphia-inquirer-daily-news-nonprofit-lol-taxes/423960/. Accessed 3 August 2016 School of Engineering at Darthmouth (2010 Forest and Paper Industry. http://engineering.dartmouth.edu/~d30345d/courses/engs171/Paper.pdf. Accessed 2 April 2016 T. Subramani, V. Angappan. (2015. Experimental Investigation of Papercrete Concrete

Synthesis of carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives as new potential PET tracers for imaging of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1).

Science.gov (United States)

Gao, Mingzhang; Wang, Min; Zheng, Qi-Huang

2016-03-01

The target tracer carbon-11-labeled imidazopyridine- and purine-thioacetamide derivatives, N-(3-[(11)C]methoxy-4-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (3-[(11)C]4a) and N-(4-[(11)C]methoxy-3-methoxyphenyl)-2-((5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)thio)acetamide (4-[(11)C]4a); 2-((6-amino-9H-purin-8-yl)thio)-N-(3-[(11)C]methoxy-4-methoxyphenyl)acetamide (3-[(11)C]8a) and 2-((6-amino-9H-purin-8-yl)thio)-N-(4-[(11)C]methoxy-3-methoxyphenyl)acetamide (4-[(11)C]8a), were prepared by O-[(11)C]methylation of their corresponding precursors with [(11)C]CH3OTf under basic condition (2N NaOH) and isolated by a simplified solid-phase extraction (SPE) method in 50-60% radiochemical yields based on [(11)C]CO2 and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 23min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 185-555GBq/μmol. Copyright © 2016 Elsevier Ltd. All rights reserved.

Technology options for future recycling

International Nuclear Information System (INIS)

Kikuchi, T.

2001-01-01

Recycling of nuclear material is indispensable, not only for using valuable resources but also for reducing the debt which we may leave to the next generations. Advanced reprocessing technologies have been developed in several countries to deal with the diversification of nuclear fuels. Also technologies derived from reprocessing or other fuel cycle areas have continued to be developed in terms of recycling. Cost effectiveness and waste-free processing are increasingly important factors in the applicable of an alternate recycling policy. This paper introduces an example of the studies in this field conducted in some countries including Japan and considers the establishment of effective recycling methodologies taking into account the uncertainty of future recycling policy. (author)

Recycling domains in plant cell morphogenesis: small GTPase effectors, plasma membrane signalling and the exocyst.

Science.gov (United States)

Zárský, Viktor; Potocký, Martin

2010-04-01

The Rho/Rop small GTPase regulatory module is central for initiating exocytotically ACDs (active cortical domains) in plant cell cortex, and a growing array of Rop regulators and effectors are being discovered in plants. Structural membrane phospholipids are important constituents of cells as well as signals, and phospholipid-modifying enzymes are well known effectors of small GTPases. We have shown that PLDs (phospholipases D) and their product, PA (phosphatidic acid), belong to the regulators of the secretory pathway in plants. We have also shown that specific NOXs (NADPH oxidases) producing ROS (reactive oxygen species) are involved in cell growth as exemplified by pollen tubes and root hairs. Most plant cells exhibit several distinct plasma membrane domains (ACDs), established and maintained by endocytosis/exocytosis-driven membrane protein recycling. We proposed recently the concept of a 'recycling domain' (RD), uniting the ACD and the connected endosomal recycling compartment (endosome), as a dynamic spatiotemporal entity. We have described a putative GTPase-effector complex exocyst involved in exocytic vesicle tethering in plants. Owing to the multiplicity of its Exo70 subunits, this complex, along with many RabA GTPases (putative recycling endosome organizers), may belong to core regulators of RD organization in plants.

The nonlinear relationship between paper recycling and primary pulp requirements : modeling paper production and recycling in Europe

NARCIS (Netherlands)

Schenk, Niels J.; Moll, Henri C.; Potting, Josepha

Waste paper is suitable for recycling back into paper or for incineration for energy recovery. If waste paper is used for recycling, secondary pulp replaces virgin pulp. Fiber recycling is limited, however, because of physical constraints—particularly the breakage of fiber in the recycling

The Three Rs: Reduce, Reuse, Recycle.

Science.gov (United States)

Science Activities, 1991

1991-01-01

A student hand-out for a recycling unit defines the terms reduce, recycle, and reuse as they relate to solid waste management. Presents the characteristics of recyclable items such as yard wastes, metals, glass, and paper. Lists organizations through which more information about recycling can be obtained. (MCO)

Reuse, Reduce, Recycle.

Science.gov (United States)

Briscoe, Georgia

1991-01-01

Discussion of recycling paper in law libraries is also applicable to other types of libraries. Results of surveys of law libraries that investigated recycling practices in 1987 and again in 1990 are reported, and suggestions for reducing the amount of paper used and reusing as much as possible are offered. (LRW)

What can recycling in thermal reactors accomplish?

International Nuclear Information System (INIS)

Piet, Steven J.; Matthern, Gretchen E.; Jacobson, Jacob J.

2007-01-01

Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives. (authors)

What can Recycling in Thermal Reactors Accomplish?

International Nuclear Information System (INIS)

Steven Piet; Gretchen E. Matthern; Jacob J. Jacobson

2007-01-01

Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives

Synthesis and spectroscopy of clay intercalated Cu(II) bio-monomer complexes: coordination of Cu(II) with purines and nucleotides

NARCIS (Netherlands)

Weckhuysen, B.M.; Leeman, H.; Schoonheydt, R.A.

1999-01-01

The spectroscopic properties of Cu(bio-monomer)nm+ complexes [BM=bio-monomer (purine, adenine, guanine, hypoxanthine, 5-ADP and 5-GMP)] in saponite clays have been investigated by diffuse reflectance spectroscopy (DRS) in the UV-Vis-NIR region and electron paramagnetic resonance (EPR) at X-band.

TD-DFT Investigation of the Magnetic Circular Dichroism Spectra of Some Purine and Pyrimidine Bases of Nucleic Acids

DEFF Research Database (Denmark)

Fahleson, Tobias; Kauczor, Joanna; Norman, Patrick

2015-01-01

We present a computational study of the magnetic circular dichroism (MCD) spectra in the 200–300 nm wavelength region of purine and its derivative hypoxanthine, as well as of the pyrimidine bases of nucleic acids uracil, thymine, and cytosine, using the B3LYP and CAM–B3LYP functionals. Solvent...

Implementing a campus wide recycling program

International Nuclear Information System (INIS)

Alvarez, L.

2002-01-01

'Full text:' The University of Windsor is currently expanding its recycling program to include all buildings on campus, but faces two challenges: 1) uncertainty about the current waste composition and distribution on campus; and 2) uncertainty about the effectiveness of increased recycling. This project assesses the current waste composition and the attitudes of the students towards recycling, and evaluates the effectiveness of proposed recycling activities. At present, paper is the only material that is collected throughout the entire campus. Except for two buildings, all other potentially recyclable materials within buildings, such as metal, glass, and plastic beverage containers, are discarded. The main focus of this research is on beverage containers as they represent clearly identifiable materials, but other materials were examined as well. To quantify the waste, different buildings on campus were classified according to their function: academic,operational and administrative. The waste composition study indicated that approximately 33% of the campus waste which is landfilled is composed of potentially recyclable material. A survey was then conducted to gauge the campus population's views on recycling issues that could affect the design of a recycling program. Interestingly, 97% of the respondents indicated a high willingness to recycle, but were uncertain as to how and where to recycle on campus. The project is currently assessing potential diversion rates using new, clearly identifiable recycling receptacles placed within selected classrooms for all major materials. There is a significant tradeoff however because the cost for new receptacles is considerable: multiple materials containers are often placed in high pedestrian traffic locations (e.g., hallways) and not always in classrooms,of which there are often many. This project will evaluate the basic benefits and costs of implementing a more comprehensive recycling program, and recommend how other

Lamps recycling aiming at the environment preservation

International Nuclear Information System (INIS)

Yamachita, Roberto Akira; Gama, Paulo Henrique R. Pereira; Haddad, Jamil; Santos, Afonso H. Moreira; Guardia, Eduardo C.

1999-01-01

The article discusses the following issues of lamps recycling in Brazil: mercury lamps recycling, recycling potential, energy conservation and environmental impacts, enterprises lamps recycling, and incentives policy

An industry response to recycle 2000

International Nuclear Information System (INIS)

Motl, G.P.; Loiselle, V.

1996-01-01

The US DOE is expected to issue a policy early this year articulating DOE's position on the recycle of DOE radioactive scrap metal. In anticipation of this 'Recycle 2000' initiative, the nuclear industry has formed a new trade association called the Association of Radioactive Metal Recyclers (ARMR). This article describes the Recycle 2000 initiative, provides some background on the ARMR and its membership, and identifies industry views on the actions to be taken and issues to be resolved in Recycle 2000 is to become a reality

A TOCA/CDC-42/PAR/WAVE functional module required for retrograde endocytic recycling

Science.gov (United States)

Bai, Zhiyong; Grant, Barth D.

2015-01-01

Endosome-to-Golgi transport is required for the function of many key membrane proteins and lipids, including signaling receptors, small-molecule transporters, and adhesion proteins. The retromer complex is well-known for its role in cargo sorting and vesicle budding from early endosomes, in most cases leading to cargo fusion with the trans-Golgi network (TGN). Transport from recycling endosomes to the TGN has also been reported, but much less is understood about the molecules that mediate this transport step. Here we provide evidence that the F-BAR domain proteins TOCA-1 and TOCA-2 (Transducer of Cdc42 dependent actin assembly), the small GTPase CDC-42 (Cell division control protein 42), associated polarity proteins PAR-6 (Partitioning defective 6) and PKC-3/atypical protein kinase C, and the WAVE actin nucleation complex mediate the transport of MIG-14/Wls and TGN-38/TGN38 cargo proteins from the recycling endosome to the TGN in Caenorhabditis elegans. Our results indicate that CDC-42, the TOCA proteins, and the WAVE component WVE-1 are enriched on RME-1–positive recycling endosomes in the intestine, unlike retromer components that act on early endosomes. Furthermore, we find that retrograde cargo TGN-38 is trapped in early endosomes after depletion of SNX-3 (a retromer component) but is mainly trapped in recycling endosomes after depletion of CDC-42, indicating that the CDC-42–associated complex functions after retromer in a distinct organelle. Thus, we identify a group of interacting proteins that mediate retrograde recycling, and link these proteins to a poorly understood trafficking step, recycling endosome-to-Golgi transport. We also provide evidence for the physiological importance of this pathway in WNT signaling. PMID:25775511

Recycling Behavior: A Multidimensional Approach

Science.gov (United States)

Meneses, Gonzalo Diaz; Palacio, Asuncion Beerli

2005-01-01

This work centers on the study of consumer recycling roles to examine the sociodemographic and psychographic profile of the distribution of recycling tasks and roles within the household. With this aim in mind, an empirical work was carried out, the results of which suggest that recycling behavior is multidimensional and comprises the undertaking…

Structural Analysis of DFG-in and DFG-out Dual Src-Abl Inhibitors Sharing a Common Vinyl Purine Template

Energy Technology Data Exchange (ETDEWEB)

Zhou, Tianjun; Commodore, Lois; Huang, Wei-Sheng; Wang, Yihan; Sawyer, Tomi K.; Shakespeare, William C.; Clackson, Tim; Zhu, Xiaotian; Dalgarno, David C. (ARIAD)

2010-09-30

Bcr-Abl is the oncogenic protein tyrosine kinase responsible for chronic myeloid leukemia (CML). Treatment of the disease with imatinib (Gleevec) often results in drug resistance via kinase mutations at the advanced phases of the disease, which has necessitated the development of new mutation-resistant inhibitors, notably against the T315I gatekeeper mutation. As part of our efforts to discover such mutation resistant Abl inhibitors, we have focused on optimizing purine template kinase inhibitors, leading to the discovery of potent DFG-in and DFG-out series of Abl inhibitors that are also potent Src inhibitors. Here we present crystal structures of Abl bound by two such inhibitors, based on a common N9-arenyl purine, and that represent both DFG-in and -out binding modes. In each structure the purine template is bound deeply in the adenine pocket and the novel vinyl linker forms a non-classical hydrogen bond to the gatekeeper residue, Thr315. Specific template substitutions promote either a DFG-in or -out binding mode, with the kinase binding site adjusting to optimize molecular recognition. Bcr-Abl T315I mutant kinase is resistant to all currently marketed Abl inhibitors, and is the focus of intense drug discovery efforts. Notably, our DFG-out inhibitor, AP24163, exhibits modest activity against this mutant, illustrating that this kinase mutant can be inhibited by DFG-out class inhibitors. Furthermore our DFG-out inhibitor exhibits dual Src-Abl activity, absent from the prototypical DFG-out inhibitor, imatinib as well as its analog, nilotinib. The data presented here provides structural guidance for the further design of novel potent DFG-out class inhibitors against Src, Abl and Abl T315I mutant kinases.

Attributes to facilitate e-waste recycling behaviour

Directory of Open Access Journals (Sweden)

Senawi Nur Hidayah

2016-01-01

Full Text Available This study aims to identify the set of attributes to facilitate electronic waste (e-waste behaviour among the community. E-waste disposal is increasing from year to year in parallel with increasing of global population. The short lifespan of electronics and poor e-waste recycling behaviour is among the main contributors to the steadily increasing of e-waste generated. Current recycling rate among the nation is lacking behind, which is only 10.5%. A questionnaire survey has been conducted among the students in Universiti Teknologi Malaysia to evaluate the current e-waste recycling practice. The results showed that majority of the respondents did not recycle their e-waste on campus. Aggressive efforts is needed to realize the country’s target of 20% recycling rate in year 2020, one of the effective paths is to minimize e-waste generation via active e-waste recycling behaviour among the community. Extensive literatures have been reviewed to classify the attributes to facilitate effective e-waste recycling among the community. Total of five attributes that identified in this study which are Convenience of E- waste Recycling Infrastruture and Services, E-waste Recycling Information, Incentives For E-waste Recycling, Reminder to Recycle E-waste And E-waste Recycling Infrastructure and Services. The set of attributes identified in this study may serve as guideline for the management in designing program to foster e-waste recycling behaviour among the community.

Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment

Energy Technology Data Exchange (ETDEWEB)

Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

1995-07-01

Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed.

Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment

International Nuclear Information System (INIS)

Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

1995-07-01

Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed

Physiological Roles of Plant Post-Golgi Transport Pathways in Membrane Trafficking.

Science.gov (United States)

Uemura, Tomohiro

2016-10-01

Membrane trafficking is the fundamental system through which proteins are sorted to their correct destinations in eukaryotic cells. Key regulators of this system include RAB GTPases and soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs). Interestingly, the numbers of RAB GTPases and SNAREs involved in post-Golgi transport pathways in plant cells are larger than those in animal and yeast cells, suggesting that plants have evolved unique and complex post-Golgi transport pathways. The trans-Golgi network (TGN) is an important organelle that acts as a sorting station in the post-Golgi transport pathways of plant cells. The TGN also functions as the early endosome, which is the first compartment to receive endocytosed proteins. Several endocytosed proteins on the plasma membrane (PM) are initially targeted to the TGN/EE, then recycled back to the PM or transported to the vacuole for degradation. The recycling and degradation of the PM localized proteins is essential for the development and environmental responses in plant. The present review describes the post-Golgi transport pathways that show unique physiological functions in plants. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

A Multitarget Approach toward the Development of 8-Substituted Purines for Photoprotection and Prevention of UV-Related Damage.

Science.gov (United States)

Djuidje, Ernestine N; Dissette, Valeria; Bino, Alessia; Benetti, Simonetta; Balzarini, Jan; Liekens, Sandra; Manfredini, Stefano; Vertuani, Silvia; Baldisserotto, Anna

2017-05-22

Ultraviolet (UV) light is the most abundant and significant modifiable risk factor for skin cancer and many other skin diseases such as early photo-aging. Across the solar radiation spectrum, UV light is the main cause behind skin problems. In the search for novel photoprotective compounds, a new series of 8-substituted purines were synthesized from commercially available 6-hydroxy-4,5-diaminopyrimidine hemisulfate or 4,5-diaminopyrimidine. All title compounds were investigated for their UV filtering, antioxidant, antifungal, and antiproliferative activities. For the photoprotection assays we used a diffuse transmittance technique to determine the sun protection factor (SPF) in vitro, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP) tests for evaluating the antioxidant activity of the more potent compounds. Among them, 8-(2,5-dihydroxyphenyl)-7H-purin-6-ol (compound 26) proved to be a good radical scavenger and is also endowed with broad-spectrum UVA filtering capabilities, suitable for further development as a protective molecule. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ni2+-binding RNA motifs with an asymmetric purine-rich internal loop and a G-A base pair.

Science.gov (United States)

Hofmann, H P; Limmer, S; Hornung, V; Sprinzl, M

1997-01-01

RNA molecules with high affinity for immobilized Ni2+ were isolated from an RNA pool with 50 randomized positions by in vitro selection-amplification. The selected RNAs preferentially bind Ni2+ and Co2+ over other cations from first series transition metals. Conserved structure motifs, comprising about 15 nt, were identified that are likely to represent the Ni2+ binding sites. Two conserved motifs contain an asymmetric purine-rich internal loop and probably a mismatch G-A base pair. The structure of one of these motifs was studied with proton NMR spectroscopy and formation of the G-A pair at the junction of helix and internal loop was demonstrated. Using Ni2+ as a paramagnetic probe, a divalent metal ion binding site near this G-A base pair was identified. Ni2+ ions bound to this motif exert a specific stabilization effect. We propose that small asymmetric purine-rich loops that contain a G-A interaction may represent a divalent metal ion binding site in RNA. PMID:9409620

Recycling of used oil

International Nuclear Information System (INIS)

Vipulanandan, C.; Ghurye, G.

1992-01-01

This paper reports on used oil which is a valuable resource that should be recycled. Recycling used oil saves energy and natural resources. Used oil can be reprocessed and used as fuel in industrial burners and boilers. Unfortunately, more than 400 million gallons/year of used oil is lost through widespread dumping, partly due to lack of effective recycling procedures. Although used oil is not currently a federally listed hazardous waste, the U.S. EPA has proposed to list it as a hazardous waste, which will make recycling of used oil even more attractive. Laboratory samples, representing used oil, were used for detailed parametric studies and to determine the limitation of extending some of the current physical separation techniques such as sedimentation and centrifuging developed for oil-water and solid-liquid separation

Challenges in plastics recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

2015-01-01

Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

A G-C-rich palindromic structural motif and a stretch of single-stranded purines are required for optimal packaging of Mason-Pfizer monkey virus (MPMV) genomic RNA.

Science.gov (United States)

Jaballah, Soumeya Ali; Aktar, Suriya J; Ali, Jahabar; Phillip, Pretty Susan; Al Dhaheri, Noura Salem; Jabeen, Aayesha; Rizvi, Tahir A

2010-09-03

During retroviral RNA packaging, two copies of genomic RNA are preferentially packaged into the budding virus particles whereas the spliced viral RNAs and the cellular RNAs are excluded during this process. Specificity towards retroviral RNA packaging is dependent upon sequences at the 5' end of the viral genome, which at times extend into Gag sequences. It has earlier been suggested that the Mason-Pfizer monkey virus (MPMV) contains packaging sequences within the 5' untranslated region (UTR) and Gag. These studies have also suggested that the packaging determinants of MPMV that lie in the UTR are bipartite and are divided into two regions both upstream and downstream of the major splice donor. However, the precise boundaries of these discontinuous regions within the UTR and the role of the intervening sequences between these dipartite sequences towards MPMV packaging have not been investigated. Employing a combination of genetic and structural prediction analyses, we have shown that region "A", immediately downstream of the primer binding site, is composed of 50 nt, whereas region "B" is composed of the last 23 nt of UTR, and the intervening 55 nt between these two discontinuous regions do not contribute towards MPMV RNA packaging. In addition, we have identified a 14-nt G-C-rich palindromic sequence (with 100% autocomplementarity) within region A that has been predicted to fold into a structural motif and is essential for optimal MPMV RNA packaging. Furthermore, we have also identified a stretch of single-stranded purines (ssPurines) within the UTR and 8 nt of these ssPurines are duplicated in region B. The native ssPurines or its repeat in region B when predicted to refold as ssPurines has been shown to be essential for RNA packaging, possibly functioning as a potential nucleocapsid binding site. Findings from this study should enhance our understanding of the steps involved in MPMV replication including RNA encapsidation process. Copyright (c) 2010 Elsevier Ltd

Studies on recycled aggregates-based concrete.

Science.gov (United States)

Rakshvir, Major; Barai, Sudhirkumar V

2006-06-01

Reduced extraction of raw materials, reduced transportation cost, improved profits, reduced environmental impact and fast-depleting reserves of conventional natural aggregates has necessitated the use of recycling, in order to be able to conserve conventional natural aggregate. In this study various physical and mechanical properties of recycled concrete aggregates were examined. Recycled concrete aggregates are different from natural aggregates and concrete made from them has specific properties. The percentages of recycled concrete aggregates were varied and it was observed that properties such as compressive strength showed a decrease of up to 10% as the percentage of recycled concrete aggregates increased. Water absorption of recycled aggregates was found to be greater than natural aggregates, and this needs to be compensated during mix design.

U.S. Department of Energy National Center of Excellence for Metals Recycle

International Nuclear Information System (INIS)

Adams, V.; Bennett, M.; Bishop, L.

1998-05-01

The US Department of Energy (DOE) National Center of Excellence for Metals Recycle has recently been established. The vision of this new program is to develop a DOE culture that promotes pollution prevention by considering the recycle and reuse of metal as the first and primary disposition option and burial as a last option. The Center of Excellence takes the approach that unrestricted release of metal is the first priority because it is the most cost-effective disposition pathway. Where this is not appropriate, restricted release, beneficial reuse, and stockpile of ingots are considered. Current recycling activities include the sale of 40,000 tons of scrap metal from the East Tennessee Technology Park (formerly K-25 Plant) K-770 scrap yard, K-1064 surplus equipment and machinery, 7,000 PCB-contaminated drums, 12,000 tons of metal from the Y-l2 scrap yard, and 1,000 metal pallets. In addition, the Center of Excellence is developing a toolbox for project teams that will contain a number of specific tools to facilitate metals recycle. This Internet-based toolbox will include primers, computer programs, and case studies designed to help sites to perform life cycle analysis, perform ALARA (As Low As is Reasonably Achievable) analysis for radiation exposures, provide pollution prevention information and documentation, and produce independent government estimates. The use of these tools is described for two current activities: disposition of scrap metal in the Y-12 scrapyard, and disposition of PCB-contaminated drums

Adaptive responses to cefotaxime treatment in ESBL-producing Escherichia coli and the possible use of significantly regulated pathways as novel secondary targets

DEFF Research Database (Denmark)

Møller, Thea S. B.; Rau, Martin Holm; Bonde, Charlotte S

2016-01-01

The aim of the study was to determine how ESBL-producing Escherichia coli change the expression of metabolic and biosynthesis genes when adapting to inhibitory concentrations of cefotaxime. Secondly, it was investigated whether significantly regulated pathways constitute putative secondary targets......-fold). Inhibition and/or mutations in other genes that were significantly regulated, belonging to energy synthesis, purine synthesis, proline uptake or potassium uptake, also rendered the resistant bacteria more susceptible to cefotaxime. The results show that ESBL-producing E. coli adapt to treatment...

Innovative Vacuum Distillation for Magnesium Recycling

Science.gov (United States)

Zhu, Tianbai; Li, Naiyi; Mei, Xiaoming; Yu, Alfred; Shang, Shixiang

Magnesium recycling now becomes a very important subject as magnesium consumption increases fast around the world. All commonly used magnesium die-casting alloys can be recycled and recovered to the primary metal quality. The recycled materials may be comprised of biscuits, sprues, runners, flash, overflows, dross, sludge, scrap parts, and old parts that are returned from service, An innovative magnesium recycle method, vacuum distillation, is developed and proved out to be able to recycle magnesium scraps, especially machining chips, oily magnesium, smelting sludge, dross or the mixture. With this process at a specific temperature and environment condition, magnesium in scraps can be gasified and then solidified to become crystal magnesium crown. This `recycled' magnesium crown is collected and used as the raw material of magnesium alloys. The experimental results show the vacuum distillation is a feasible and plausible method to recycle magnesium. Further, the cost analysis will be addressed in this paper.

Management and recycling of electronic waste

International Nuclear Information System (INIS)

Tanskanen, Pia

2013-01-01

Waste electrical and electronic equipment (WEEE) is one of the largest growing waste streams globally. Hence, for a sustainable environment and the economic recovery of valuable material for reuse, the efficient recycling of electronic scrap has been rendered indispensable, and must still be regarded as a major challenge for today’s society. In contrast to the well-established recycling of metallic scrap, it is much more complicated to recycle electronics products which have reached the end of their life as they contain many different types of material types integrated into each other. As illustrated primarily for the recycling of mobile phones, the efficient recycling of WEEE is not only a challenge for the recycling industry; it is also often a question of as-yet insufficient collection infrastructures and poor collection efficiencies, and a considerable lack of the consumer’s awareness for the potential of recycling electronics for the benefit of the environment, as well as for savings in energy and raw materials

The Compressor Recycle System

OpenAIRE

Barstad, Bjørn Ove

2010-01-01

The compressor recycle system is the main focus of this thesis. When the mass flow through a compressor becomes too low, the compressor can plunge into surge. Surge is a term that is used for axisymmetric oscillation through a compressor and is highly unwanted. The recycle system feeds compressed gas back to the intake when the mass flow becomes too low, and thereby act as a safety system.A mathematical model of the recycle system is extended and simulated in SIMULINK. The mathematical model ...

Metabolic pathways of lung inflammation revealed by high-resolution metabolomics (HRM) of H1N1 influenza virus infection in mice.

Science.gov (United States)

Chandler, Joshua D; Hu, Xin; Ko, Eun-Ju; Park, Soojin; Lee, Young-Tae; Orr, Michael; Fernandes, Jolyn; Uppal, Karan; Kang, Sang-Moo; Jones, Dean P; Go, Young-Mi

2016-11-01

Influenza is a significant health concern worldwide. Viral infection induces local and systemic activation of the immune system causing attendant changes in metabolism. High-resolution metabolomics (HRM) uses advanced mass spectrometry and computational methods to measure thousands of metabolites inclusive of most metabolic pathways. We used HRM to identify metabolic pathways and clusters of association related to inflammatory cytokines in lungs of mice with H1N1 influenza virus infection. Infected mice showed progressive weight loss, decreased lung function, and severe lung inflammation with elevated cytokines [interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ] and increased oxidative stress via cysteine oxidation. HRM showed prominent effects of influenza virus infection on tryptophan and other amino acids, and widespread effects on pathways including purines, pyrimidines, fatty acids, and glycerophospholipids. A metabolome-wide association study (MWAS) of the aforementioned inflammatory cytokines was used to determine the relationship of metabolic responses to inflammation during infection. This cytokine-MWAS (cMWAS) showed that metabolic associations consisted of distinct and shared clusters of 396 metabolites highly correlated with inflammatory cytokines. Strong negative associations of selected glycosphingolipid, linoleate, and tryptophan metabolites with IFN-γ contrasted strong positive associations of glycosphingolipid and bile acid metabolites with IL-1β, TNF-α, and IL-10. Anti-inflammatory cytokine IL-10 had strong positive associations with vitamin D, purine, and vitamin E metabolism. The detailed metabolic interactions with cytokines indicate that targeted metabolic interventions may be useful during life-threatening crises related to severe acute infection and inflammation. Copyright © 2016 the American Physiological Society.

MOX recycling-an industrial reality

International Nuclear Information System (INIS)

Shallo, G.D.F.

1996-01-01

Reprocessing and plutonium recycling have now attained industrial maturity in France and Europe. Specifically, mixed-oxide (MOX) fuel is fabricated and used in light water reactors (LWRs) in satisfactory operating conditions. The utilities and the fuel cycle industry experience no technical difficulties, and European recycling programs are growing steadily, from 18 reactors in operation today up to 50 expected around the year 2000, putting the system reprocessing-recycling in coherence: 25 t of plutonium will then be used each year to produce the electricity equivalence of 25 millions tons of oil. Plutonium recycling in MOX fuel in current LWRs proves to be technically safe and economically competitive and meets natural resource savings and environmental protection objectives. And recycling responds properly to the nonproliferation concerns. Such an industrial experience gives a unique reference for weapons plutonium disposition through MOX use in reactors

ZZ WPPR, Pu Recycling Benchmark Results

International Nuclear Information System (INIS)

Lutz, D.; Mattes, M.; Delpech, Marc; Juanola, Marc

2002-01-01

Description of program or function: The NEA NSC Working Party on Physics of Plutonium Recycling has commissioned a series of benchmarks covering: - Plutonium recycling in pressurized-water reactors; - Void reactivity effect in pressurized-water reactors; - Fast Plutonium-burner reactors: beginning of life; - Plutonium recycling in fast reactors; - Multiple recycling in advanced pressurized-water reactors. The results have been published (see references). ZZ-WPPR-1-A/B contains graphs and tables relative to the PWR Mox pin cell benchmark, representing typical fuel for plutonium recycling, one corresponding to a first cycle, the second for a fifth cycle. These computer readable files contain the complete set of results, while the printed report contains only a subset. ZZ-WPPR-2-CYC1 are the results from cycle 1 of the multiple recycling benchmarks

Sustainable hydrocarbon fuels by recycling CO2 and H2O with renewable or nuclear energy

DEFF Research Database (Denmark)

Graves, Christopher R.; Ebbesen, Sune; Mogensen, Mogens Bjerg

2011-01-01

) and biofuels have received the most attention, similar hydrocarbons can be produced without using fossil fuels or biomass. Using renewable and/or nuclear energy, carbon dioxide and water can be recycled into liquid hydrocarbon fuels in non-biological processes which remove oxygen from CO2 and H2O (the reverse...... of fuel combustion). Capture of CO2 from the atmosphere would enable a closed-loop carbon-neutral fuel cycle. This article critically reviews the many possible technological pathways for recycling CO2 into fuels using renewable or nuclear energy, considering three stages—CO2 capture, H2O and CO2...... by Fischer–Tropsch synthesis is identified as one of the most promising, feasible routes. An analysis of the energy balance and economics of this CO2 recycling process is presented. We estimate that the full system can feasibly operate at 70% electricity-to-liquid fuel efficiency (higher heating value basis...

Frequent Questions on Recycling

Science.gov (United States)

This is a list of frequent questions on recycling, broken down into five categories. These are answers to common questions that EPA has received from press and web inquiries. This list is located on the Reduce, Reuse, Recycle website.

Ionization of Purine Tautomers in Nucleobases, Nucleosides, and Nucleotides: From the Gas Phase to the Aqueous Environment

Czech Academy of Sciences Publication Activity Database

Pluhařová, Eva; Jungwirth, Pavel; Bradforth, S. E.; Slavíček, P.

2011-01-01

Roč. 115, č. 5 (2011), s. 1294-1305 ISSN 1520-6106 R&D Projects: GA MŠk LC512; GA ČR GA203/08/0114 Grant - others:GA ČR(CZ) GA203/09/0422 Program:GA Institutional research plan: CEZ:AV0Z40550506 Keywords : DNA bases * purines * ab initio Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.696, year: 2011

Recycled concrete with coarse recycled aggregate. An overview and analysis

Directory of Open Access Journals (Sweden)

B. González-Fonteboa

2018-04-01

Full Text Available The construction field has contributed to environmental degradation, producing a high amount of construction and demolition waste (C&D waste and consuming large volumes of natural resources. In this context, recycled concrete (RC has been recognised as a means to preserve natural resources and reduce space for waste storage. During the last decades, many researchers have developed works studying different recycled concrete properties. This review focuses on structural RC made with coarse recycled aggregate from concrete waste. The main objective is to provide a state of the art report on RC’s properties and an analysis on how to predict them taking into account relevant research works. Moreover, the study tries to collect and update RC findings, proposing equations to define RC’s performance, in terms of mechanical strength, modulus of elasticity, stress-strain, creep and shrinkage.

The effect of exhaustive exercise on the concentration of purine nucleotides and their metabolites in erythrocytes

OpenAIRE

E Skotnicka; I Baranowska-Bosiacka; W Dudzińska; M Suska; R Nowak; K Krupecki; AJ Hłyńczak

2008-01-01

In this study we tried to obtain a complete overview of purine nucleotide metabolism in erythrocytes before and during an incremental, intermittent exhaustive exercise bout protocol for sportsmen (high-performance rowers) and untrained, healthy, active volunteers. Erythrocyte levels of the main nucleotides (ATP, ADP, AMP, GTP, GDP, GMP, IMP, NAD and NADP ), nucleosides (Ado, Guo, Ino) and the base Hyp were measured using the HPLC method. The parameters that can be deducted from their concent...

Solid waste recycling in Rajshahi city of Bangladesh.

Science.gov (United States)

Bari, Q Hamidul; Hassan, K Mahbub; Haque, M Ehsanul

2012-11-01

Efficient recycling of solid wastes is now a global concern for a sustainable and environmentally sound management. In this study, traditional recycling pattern of solid waste was investigated in Rajshahi municipality which is the fourth largest city of Bangladesh. A questionnaire survey had been carried out in various recycle shops during April 2010 to January 2011. There were 140 recycle shops and most of them were located in the vicinity of Stadium market in Rajshahi. About 1906 people were found to be involved in recycling activities of the city. The major fraction of recycled wastes were sent to capital city Dhaka for further manufacture of different new products. Only a small amount of wastes, specially plastics, were processed in local recycle factories to produce small washing pots and bottle caps. Everyday, an estimated 28.13 tons of recycled solid wastes were handled in Rajshahi city area. This recycled portion accounted for 8.25% of the daily total generated wastes (341 ton d(-1)), 54.6% of total recyclable wastes (51.49 ton d(-1)) and 68.29% of readily recyclable wastes (41.19 ton d(-1)). Major recycled materials were found to be iron, glass, plastic, and papers. Only five factories were involved in preliminary processing of recyclable wastes. Collecting and processing secondary materials, manufacturing recycled-content products, and then buying recycled products created a circle or loop that ensured the overall success of recycling and generated a host of financial, environmental, and social returns. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Plasma Membrane Sialidase NEU3 Regulates the Malignancy of Renal Carcinoma Cells by Controlling β1 Integrin Internalization and Recycling*

Science.gov (United States)

Tringali, Cristina; Lupo, Barbara; Silvestri, Ilaria; Papini, Nadia; Anastasia, Luigi; Tettamanti, Guido; Venerando, Bruno

2012-01-01

The human plasma membrane sialidase NEU3 is a key enzyme in the catabolism of membrane gangliosides, is crucial in the regulation of cell surface processes, and has been demonstrated to be significantly up-regulated in renal cell carcinomas (RCCs). In this report, we show that NEU3 regulates β1 integrin trafficking in RCC cells by controlling β1 integrin recycling to the plasma membrane and controlling activation of the epidermal growth factor receptor (EGFR) and focal adhesion kinase (FAK)/protein kinase B (AKT) signaling. NEU3 silencing in RCC cells increased the membrane ganglioside content, in particular the GD1a content, and changed the expression of key regulators of the integrin recycling pathway. In addition, NEU3 silencing up-regulated the Ras-related protein RAB25, which directs internalized integrins to lysosomes, and down-regulated the chloride intracellular channel protein 3 (CLIC3), which induces the recycling of internalized integrins to the plasma membrane. In this manner, NEU3 silencing enhanced the caveolar endocytosis of β1 integrin, blocked its recycling and reduced its levels at the plasma membrane, and, consequently, inhibited EGFR and FAK/AKT. These events had the following effects on the behavior of RCC cells: they (a) decreased drug resistance mediated by the block of autophagy and the induction of apoptosis; (b) decreased metastatic potential mediated by down-regulation of the metalloproteinases MMP1 and MMP7; and (c) decreased adhesion to collagen and fibronectin. Therefore, our data identify NEU3 as a key regulator of the β1 integrin-recycling pathway and FAK/AKT signaling and demonstrate its crucial role in RCC malignancy. PMID:23139422

Carambola optics for recycling of light.

Science.gov (United States)

Leutz, Ralf; Fu, Ling; Ries, Harald

2006-04-20

Recycling of light allows the luminance (radiance) emitted by a light source to be increased at the cost of reducing the total luminous flux (radiant power). Recycling of light means returning part of the emitted light to the source, where part of it will escape absorption. An optical design that is suitable for multiple and controlled recycling is described. Carambola optics is named for its resemblance to star fruit. Several pairs of mirrors or prisms redirect light repeatedly onto the source, thus achieving multiple transits of the light through the source. This recycled light exits the carambola in the same phase space as light directly emitted and not recycled.

Text recycling: acceptable or misconduct?

Science.gov (United States)

Harriman, Stephanie; Patel, Jigisha

2014-08-16

Text recycling, also referred to as self-plagiarism, is the reproduction of an author's own text from a previous publication in a new publication. Opinions on the acceptability of this practice vary, with some viewing it as acceptable and efficient, and others as misleading and unacceptable. In light of the lack of consensus, journal editors often have difficulty deciding how to act upon the discovery of text recycling. In response to these difficulties, we have created a set of guidelines for journal editors on how to deal with text recycling. In this editorial, we discuss some of the challenges of developing these guidelines, and how authors can avoid undisclosed text recycling.

U.S. Department of Energy National Center of Excellence for Metals Recycle

International Nuclear Information System (INIS)

Adams, V.; Bennett, M.; Bishop, L.

1998-06-01

The US Department of Energy (DOE) National Center of Excellence for Metals Recycle has recently been established. The vision of this new program is to develop a DOE culture that promotes pollution prevention by considering the recycle and reuse of metal as the first and primary disposition option and burial as a last option. The Center of Excellence takes the approach that unrestricted release of metal is the first priority because it is the most cost-effective disposition pathway. Where this is not appropriate, restricted release, beneficial reuse, and stockpile of ingots are considered. The Center has gotten off to a fast start. Current recycling activities include the sale of 40,000 tons of scrap metal from the East Tennessee Technology Park (formerly K-25 Plant) K-770 scrap yard, K-1064 surplus equipment and machinery, 7,000 PCB-contaminated drums, 12,000 tons of metal from the Y-12 scrap yard, and 1,000 metal pallets. In addition, the Center of Excellence is developing a toolbox for project teams that will contain a number of specific tools to facilitate metals recycle. This Internet-based toolbox will include primers, computer software, and case studies designed to help sites to perform life cycle analysis, perform ALARA (As Low As is Reasonably Achievable) analysis for radiation exposures, produce pollution prevention information and documentation, manage their materials inventory, produce independent government estimates, and implement sale/service contracts. The use of these tools is described for two current activities: disposition of scrap metal in the Y-12 scrap yard, and disposition of PCB-contaminated drums. Members of the Center look forward to working with all DOE sites, regulatory authorities, the private sector, and other stakeholders to achieve the metals recycle goals

Structural recycled concrete: utilization of recycled aggregate from construction and demolition wastes

International Nuclear Information System (INIS)

Alaejos Gutierrez, P.; Sanchez de Juan, M.

2015-01-01

This paper aims to present the main results of CEDEX research works concerning the use of recycled aggregates for structural concretes. By way of conclusion, recommendations on the requirements of the recycled aggregates have been established, providing information about the influence of these aggregates on the properties of structural concrete. (Author)

Prediction of rumen microbial outflow based on urinary excretion of purine derivatives

International Nuclear Information System (INIS)

Nolan, J.V.

1999-01-01

The method for predicting microbial protein outflow from the rumen based on the excretion of purine derivatives (PD) in the urine is being increasingly used by nutritionists. In contrast to methods that depend on estimates of digesta flow, the PD method does not require animals to be fitted surgically with cannulae into the gut, and studies can be performed with minimal disturbance to the experimental animals. Methods of analysis of PD have been improved and standardized. Certain assumptions, however, are required that could lead to errors when this method is used to predict microbial protein outflow from the rumen. The need for further investigation of these assumptions by means of isotopic tracers and other techniques is examined. (author)

Plastics recycling: challenges and opportunities.

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-07-27

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

Plastics recycling: challenges and opportunities

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-01-01

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

Recycling in the 90's - a shared responsibility

International Nuclear Information System (INIS)

Anon.

1993-01-01

Recycling means different things to different people. To consumers, recycling can mean putting out bottles and cans for curbside collection. To a product maker - a manufacturer of raw materials, fabricator of goods or products, or brand owner - recycling can mean reformulating goods to include recycled materials. To recycling service providers, recycling can mean providing cost-efficient collection services. To public policy makers in all levels of government recycling can mean establishing collection and utilization regulations. For recycling to work successfully, these diverse groups must work together and share responsibility for its success. Also, if recycling is to succeed on a large scale and over the long term, three critical points must be first addressed: These points are: approach, economics, and markets. These points are discussed

Legionella Effector AnkX Disrupts Host Cell Endocytic Recycling in a Phosphocholination-Dependent Manner

Directory of Open Access Journals (Sweden)

Samual C. Allgood

2017-09-01

Full Text Available The facultative intracellular bacterium Legionella pneumophila proliferates within amoebae and human alveolar macrophages, and it is the causative agent of Legionnaires' disease, a life-threatening pneumonia. Within host cells, L. pneumophila establishes a replicative haven by delivering numerous effector proteins into the host cytosol, many of which target membrane trafficking by manipulating the function of Rab GTPases. The Legionella effector AnkX is a phosphocholine transferase that covalently modifies host Rab1 and Rab35. However, a detailed understanding of the biological consequence of Rab GTPase phosphocholination remains elusive. Here, we broaden the understanding of AnkX function by presenting three lines of evidence that it interferes with host endocytic recycling. First, using immunogold transmission electron microscopy, we determined that GFP-tagged AnkX ectopically produced in mammalian cells localizes at the plasma membrane and tubular membrane compartments, sites consistent with targeting the endocytic recycling pathway. Furthermore, the C-terminal region of AnkX was responsible for association with the plasma membrane, and we determined that this region was also able to bind the phosphoinositide lipids PI(3P and PI(4P in vitro. Second, we observed that mCherry-AnkX co-localized with Rab35, a regulator of recycling endocytosis and with major histocompatibility class I protein (MHC-I, a key immunoregulatory protein whose recycling from and back to the plasma membrane is Rab35-dependent. Third, we report that during infection of macrophages, AnkX is responsible for the disruption of endocytic recycling of transferrin, and AnkX's phosphocholination activity is critical for this function. These results support the hypothesis that AnkX targets endocytic recycling during host cell infection. Finally, we have demonstrated that the phosphocholination activity of AnkX is also critical for inhibiting fusion of the Legionella

Compressive strength improvement for recycled concrete aggregate

Directory of Open Access Journals (Sweden)

Mohammed Dhiyaa

2018-01-01

Full Text Available Increasing amount of construction waste and, concrete remnants, in particular pose a serious problem. Concrete waste exist in large amounts, do not decay and need long time for disintegration. Therefore, in this work old demolished concrete is crashed and recycled to produce recycled concrete aggregate which can be reused in new concrete production. The effect of using recycled aggregate on concrete compressive strength has been experimentally investigated; silica fume admixture also is used to improve recycled concrete aggregate compressive strength. The main parameters in this study are recycled aggregate and silica fume admixture. The percent of recycled aggregate ranged from (0-100 %. While the silica fume ranged from (0-10 %. The experimental results show that the average concrete compressive strength decreases from 30.85 MPa to 17.58 MPa when the recycled aggregate percentage increased from 0% to 100%. While, when silica fume is used the concrete compressive strength increase again to 29.2 MPa for samples with 100% of recycled aggregate.

Errores innatos del metabolismo de las purinas y otras enfermedades relacionadas Inborn purine metabolism errors and other related diseases

Directory of Open Access Journals (Sweden)

Jiovanna Contreras Roura

2012-06-01

Full Text Available Los errores innatos en el metabolismo de las purinas son trastornos hereditarios complejos de gran impacto clínico, que presentan síntomas variables de acuerdo con el tipo de enfermedad. Pueden presentarse problemas renales de origen desconocido, retardo mental con manifestaciones neurológicas, retardo del crecimiento, infecciones recurrentes, automutilación, inmunodeficiencias, anemia hemolítica inexplicable, artritis gotosa, historia familiar, consanguinidad y reacciones adversas a fármacos que son análogos de las purinas. Las investigaciones de estas enfermedades comienzan generalmente con la cuantificación del ácido úrico en suero y en orina, por ser el producto final del metabolismo de las purinas en humanos. La dieta y el consumo de medicamentos, entre otras condiciones patológicas, fisiológicas y clínicas, también pueden modificar los niveles de este compuesto. Esta revisión pretende divulgar información de los errores innatos en el metabolismo de las purinas, y facilitar la interpretación de los niveles del ácido úrico y otros marcadores bioquímicos útiles en el diagnóstico de estas enfermedades. Se incluyen tablas que relacionan estas enfermedades con los niveles de excreción de ácido úrico y otros marcadores bioquímicos, las enzimas alteradas, los síntomas clínicos, el modo de herencia y, en algunos casos, el tratamiento propuesto. Este trabajo nos permite afirmar que las variaciones en los niveles del ácido úrico y la presencia de otros marcadores bioquímicos en orina, constituyen una herramienta importante en la pesquisa de algunos errores innatos en el metabolismo de las purinas, así como de otras condiciones patológicas relacionadas.Inborn purine metabolism errors are complex inherited disorders of great clinical impact that present with variable symptoms according to the type of disease. It might occur renal problems of unknown origin, metal retardation with neurological manifestations, retarded

Cost effectiveness of recycling: A systems model

Energy Technology Data Exchange (ETDEWEB)

Tonjes, David J., E-mail: david.tonjes@stonybrook.edu [Department of Technology and Society, College of Engineering and Applied Sciences, Stony Brook University, Stony Brook, NY 11794-3560 (United States); Waste Reduction and Management Institute, School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000 (United States); Center for Bioenergy Research and Development, Advanced Energy Research and Technology Center, Stony Brook University, 1000 Innovation Rd., Stony Brook, NY 11794-6044 (United States); Mallikarjun, Sreekanth, E-mail: sreekanth.mallikarjun@stonybrook.edu [Department of Technology and Society, College of Engineering and Applied Sciences, Stony Brook University, Stony Brook, NY 11794-3560 (United States)

2013-11-15

Highlights: • Curbside collection of recyclables reduces overall system costs over a range of conditions. • When avoided costs for recyclables are large, even high collection costs are supported. • When avoided costs for recyclables are not great, there are reduced opportunities for savings. • For common waste compositions, maximizing curbside recyclables collection always saves money. - Abstract: Financial analytical models of waste management systems have often found that recycling costs exceed direct benefits, and in order to economically justify recycling activities, externalities such as household expenses or environmental impacts must be invoked. Certain more empirically based studies have also found that recycling is more expensive than disposal. Other work, both through models and surveys, have found differently. Here we present an empirical systems model, largely drawn from a suburban Long Island municipality. The model accounts for changes in distribution of effort as recycling tonnages displace disposal tonnages, and the seven different cases examined all show that curbside collection programs that manage up to between 31% and 37% of the waste stream should result in overall system savings. These savings accrue partially because of assumed cost differences in tip fees for recyclables and disposed wastes, and also because recycling can result in a more efficient, cost-effective collection program. These results imply that increases in recycling are justifiable due to cost-savings alone, not on more difficult to measure factors that may not impact program budgets.

Reusing recycled aggregates in structural concrete

Science.gov (United States)

Kou, Shicong

The utilization of recycled aggregates in concrete can minimize environmental impact and reduce the consumption of natural resources in concrete applications. The aim of this thesis is to provide a scientific basis for the possible use of recycled aggregates in structure concrete by conducting a comprehensive programme of laboratory study to gain a better understanding of the mechanical, microstructure and durability properties of concrete produced with recycled aggregates. The study also explored possible techniques to of improve the properties of recycled aggregate concrete that is produced with high percentages (≧ 50%) of recycled aggregates. These techniques included: (a) using lower water-to-cement ratios in the concrete mix design; (b) using fly ash as a cement replacement or as an additional mineral admixture in the concrete mixes, and (c) precasting recycled aggregate concrete with steam curing regimes. The characteristics of the recycled aggregates produced both from laboratory and a commercially operated pilot construction and demolition (C&D) waste recycling plant were first studied. A mix proportioning procedure was then established to produce six series of concrete mixtures using different percentages of recycled coarse aggregates with and without the use of fly ash. The water-to-cement (binder) ratios of 0.55, 0.50, 0.45 and 0.40 were used. The fresh properties (including slump and bleeding) of recycled aggregate concrete (RAC) were then quantified. The effects of fly ash on the fresh and hardened properties of RAC were then studied and compared with those RAC prepared with no fly ash addition. Furthermore, the effects of steam curing on the hardened properties of RAC were investigated. For micro-structural properties, the interfacial transition zones of the aggregates and the mortar/cement paste were analyzed by SEM and EDX-mapping. Moreover, a detailed set of results on the fracture properties for RAC were obtained. Based on the experimental

The Diffusion Effect of MSW Recycling

OpenAIRE

Yi-Tui Chen; Fu-Chiang Yang; Shih-Heng Yu

2017-01-01

The purpose of this paper is to compare the recycling performance for some waste fractions selected including food waste, bulk waste, paper, metal products, plastics/rubber and glass products and then to develop some directions for the future improvements. The priority of each waste fraction for recycling is also analyzed by using an importance-performance analysis. Traditionally, the recycling rate that is calculated by the ratio of waste recycled to waste collected is used as an indicator t...

Coolant clean-up and recycle systems

International Nuclear Information System (INIS)

Ito, Takao.

1979-01-01

Purpose: To increase the service life of mechanical seals in a shaft sealing device, eliminate leakages and improve the safety by providing a recycle pump for feeding coolants to a coolant clean-up device upon reactor shut-down and adapting the pump treat only low temperature and low pressure coolants. Constitution: The system is adapted to partially take out coolants from the pipeways of a recycling pump upon normal operation and feed them to a clean-up device. Upon reactor shut-down, the recycle pump is stopped and coolants are extracted by the recycle pump for shut-down into the clean-up device. Since the coolants are not fed to the clean-up device by the recycle pump during normal operation as conducted so far, high temperature and high pressure coolants are not directly fed to the recycle pump, thereby enabling to avoid mechanical problems in the pump. (Kamimura, M.)

Trisubstituted purine inhibitors of PDGFR alpha and their antileukemic activity in the human eosinophilic cell line EOL-1

Czech Academy of Sciences Publication Activity Database

Malínková, Veronika; Řezníčková, Eva; Jorda, Radek; Gucký, T.; Kryštof, Vladimír

2017-01-01

Roč. 25, č. 24 (2017), s. 6523-6535 ISSN 0968-0896 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : dependent kinase inhibitors * src tyrosine kinase * 2,6,9-trisubstituted purines * therapeutic target * potent inhibitor * imatinib * leukemia * mutations * mutant * domain Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Hematology Impact factor: 2.930, year: 2016

Synthesis of purines bearing functionalized C-substituents by the conjugate addition of nucleophiles to 6-vinylpurines and 6-ethynylpurines

Czech Academy of Sciences Publication Activity Database

Kuchař, Martin; Pohl, Radek; Votruba, Ivan; Hocek, Michal

-, č. 22 (2006), s. 5083 -5098 ISSN 1434-193X R&D Projects: GA MŠk(CZ) 1M0508; GA AV ČR(CZ) 1QS400550501 Institutional research plan: CEZ:AV0Z40550506 Keywords : purines * Michael addition * conjugate additions * cross-coupling Subject RIV: CC - Organic Chemistry Impact factor: 2.769, year: 2006

Japan's fuel recycling policy

International Nuclear Information System (INIS)

Anon.

1991-01-01

The Atomic Energy Commission (AEC) has formulated Japanese nuclear fuel recycling plan for the next 20 years, based on the idea that the supply and demand of plutonium should be balanced mainly through the utilization of plutonium for LWRs. The plan was approved by AEC, and is to be incorporated in the 'Long term program for development and utilization of nuclear energy' up for revision next year. The report on 'Nuclear fuel recycling in Japan' by the committee is characterized by Japanese nuclear fuel recycling plan and the supply-demand situation for plutonium, the principle of the possession of plutonium not more than the demand in conformity with nuclear nonproliferation attitude, and the establishment of a domestic fabrication system of uranium-plutonium mixed oxide fuel. The total plutonium supply up to 2010 is estimated to be about 85 t, on the other hand, the demand will be 80-90 t. The treatment of plutonium is the key to the recycling and utilization of nuclear fuel. By around 2000, the private sector will commercialize the fabrication of the MOX fuel for LWRs at the annual rate of about 100 t. Commitment to nuclear nonproliferation, future nuclear fuel recycling program in Japan, MOX fuel fabrication system in Japan and so on are reported. (K.I.)

Design study of advanced nuclear fuel recycle system. Conceptual study of recycle system using molten salt

International Nuclear Information System (INIS)

Kakehi, I.; Shirai, N.; Hatano, M.; Kajitani, M.; Yonezawa, S.; Kawai, T.; Kawamura, F.; Tobe, K.; Takahashi, K.

1996-12-01

For the purpose of developing the future nuclear fuel recycle system, the design study of the advanced nuclear fuel recycle system is being conducted. This report describes intermediate accomplishments in the conceptual system study of the advanced nuclear fuel recycle system. Fundamental concepts of this system is the recycle system using molten salt which intend to break through the conventional concepts of purex and pellet fuel system. Contents of studies in this period are as follows, 1)feasibility study of the process by Cd-cathode for nitride fuel, 2)application study for the molten salt of low melting point (AlCl3+organic salt), 3)research for decladding (advantage of decladding by heat treatment), 4)behavior of FPs in electrorefining (behavior of iodine and volatile FP chlorides, FPs behavior in chlorination), 5)criticality analysis in electrorefiner, 6)drawing of off-gas flow diagram, 7)drawing of process machinery concept (cathode processor, vibration packing), 8)evaluation for the amounts of the high level radioactive wastes, 9)quality of the recycle fuels (FPs contamination of recycle fuel), 10)conceptual study of in-cell handling system, 11)meaning of the advanced nuclear fuel recycle system. The conceptual system study will be completed in describing concepts of the system and discussing issues for the developments. (author)

Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

Energy Technology Data Exchange (ETDEWEB)

Weiler, Monica [Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany); Schmetzer, Helga [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Braeu, Marion; Buhmann, Raymund [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany)

2016-11-15

The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3{sup +}T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

International Nuclear Information System (INIS)

Weiler, Monica; Schmetzer, Helga; Braeu, Marion; Buhmann, Raymund

2016-01-01

The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3 + T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

Purine nitrogen index, potentially a new parameter for rapid feed evaluation in ruminants

International Nuclear Information System (INIS)

Chen, X.B.; Oerskov, E.R.; Subba, D.B.; Jayasuriya, M.C.N.

1999-01-01

The concept of a new parameter 'Purine Nitrogen Index (PNI)' for feed evaluation in ruminants is discussed. PNI refers to the ratio of purine derivative (PD) nitrogen to total nitrogen in urine. It is suggested that PNI can potentially be used as an indicator of the efficiency with which degradable dietary nitrogen is converted to microbial protein in the rumen. The excretion of PD in the urine provides an estimation of the intestinal flow of microbial protein, and therefore, PNI effectively corresponds to the amount of microbial protein produced in the rumen relative to the nitrogen loss in the urine. If a diet or a dietary regime has a high conversion efficiency, proportionally more rumen degradable nitrogen is converted to microbial protein and less nitrogen is excreted in the urine, resulting in a high PNI. Conversely, if a diet has a poor conversion efficiency, proportionally less dietary nitrogen is converted to microbial protein and more is excreted in the urine, resulting in a low PNI. Preliminary data from six experiments involving 34 sheep confirmed a positive correlation between PNI and the nitrogen conversion efficiency, and suggested that a dietary regime with a PNI lower than 0.08 for sheep appeared to be a less efficient in the production of microbial protein and have a greater loss of nitrogen in the urine. PNI can theoretically be determined in spot urine samples, and has the potential to serve as a 'dipstick' method for the rapid evaluation of ruminant feeds. However, more research with a mathematical modelling approach is required to evaluate and develop the concept further. (author)

Purine nitrogen index, potentially a new parameter for rapid feed evaluation in ruminants

Energy Technology Data Exchange (ETDEWEB)

Chen, X B; Oerskov, E R [Rowett Research Institute, Bucksburn, Aberdeen (United Kingdom); Subba, D B [Pakhribas Agricultural Centre, Dhankuta, Kathmandu (Nepal); Jayasuriya, M C.N. [International Atomic Energy Agency, Animal Production and Health Section, Vienna (Austria)

1999-06-01

The concept of a new parameter `Purine Nitrogen Index (PNI)` for feed evaluation in ruminants is discussed. PNI refers to the ratio of purine derivative (PD) nitrogen to total nitrogen in urine. It is suggested that PNI can potentially be used as an indicator of the efficiency with which degradable dietary nitrogen is converted to microbial protein in the rumen. The excretion of PD in the urine provides an estimation of the intestinal flow of microbial protein, and therefore, PNI effectively corresponds to the amount of microbial protein produced in the rumen relative to the nitrogen loss in the urine. If a diet or a dietary regime has a high conversion efficiency, proportionally more rumen degradable nitrogen is converted to microbial protein and less nitrogen is excreted in the urine, resulting in a high PNI. Conversely, if a diet has a poor conversion efficiency, proportionally less dietary nitrogen is converted to microbial protein and more is excreted in the urine, resulting in a low PNI. Preliminary data from six experiments involving 34 sheep confirmed a positive correlation between PNI and the nitrogen conversion efficiency, and suggested that a dietary regime with a PNI lower than 0.08 for sheep appeared to be a less efficient in the production of microbial protein and have a greater loss of nitrogen in the urine. PNI can theoretically be determined in spot urine samples, and has the potential to serve as a `dipstick` method for the rapid evaluation of ruminant feeds. However, more research with a mathematical modelling approach is required to evaluate and develop the concept further. (author) 15 refs, 5 figs, 4 tabs

Influence of recycled aggregate quality and proportioning criteria on recycled concrete properties.

Science.gov (United States)

López-Gayarre, F; Serna, P; Domingo-Cabo, A; Serrano-López, M A; López-Colina, C

2009-12-01

This paper presents the results of experimental research using concrete produced by substituting part of the natural coarse aggregates with recycled aggregates from concrete demolition. The influence of the quality of the recycled aggregate (amount of declassified and source of aggregate), the percentage of replacement on the targeted quality of the concrete to be produced (strength and workability) has been evaluated. The granular structure of concrete and replacement criteria were analyzed in this study, factors which have not been analyzed in other studies. The following properties of recycled concretes were analyzed: density, absorption, compressive strength, elastic modulus, amount of occluded air, penetration of water under pressure and splitting tensile strength. A simplified test program was designed to control the costs of the testing while still producing sufficient data to develop reliable conclusions in order to make the number of tests viable whilst guaranteeing the reliability of the conclusions. Several factors were analyzed including the type of aggregate, the percentage of replacement, the type of sieve curve, the declassified content, the strength of concrete and workability of concrete and the replacement criteria. The type of aggregate and the percentage of replacement were the only factors that showed a clear influence on most of the properties. Compressive strength is clearly affected by the quality of recycled aggregates. If the water-cement ratio is kept constant and the loss of workability due to the effect of using recycled aggregate is compensated for with additives, the percentage of replacement of the recycled aggregate will not affect the compressive strength. The elastic modulus is affected by the percentage of replacement. If the percentage of replacement does not exceed 50%, the elastic modulus will only change slightly.

Proceedings of the waste recycling workshop

Energy Technology Data Exchange (ETDEWEB)

Bailey, R.E.; Thomas, A.F.; Ries, M.A. [eds.] [Ohio State Univ., Columbus, OH (United States)

1993-12-31

Recorded are seventeen talks from five sessions at the workshop. FERMCO`s recycling program, state of the art recycling technology, and an integrated demonstration of deactivation, decommissioning and decommissioning are presented in the plenary session. In the concrete session, decontamination and recycling are discussed. In the transite session, regulations are considered along with recycling and decontamination. In the metals session, radioactive scrap metals are emphasized. And in the regulatory considerations and liabilities session, DOE and EPA viewpoints are discussed. (GHH)

Genetic Control of Ascorbic Acid Biosynthesis and Recycling in Horticultural Crops

Directory of Open Access Journals (Sweden)

Ifigeneia Mellidou

2017-07-01

Full Text Available Ascorbic acid (AsA is an essential compound present in almost all living organisms that has important functions in several aspects of plant growth and development, hormone signaling, as well as stress defense networks. In recent years, the genetic regulation of AsA metabolic pathways has received much attention due to its beneficial role in human diet. Despite the great variability within species, genotypes, tissues and developmental stages, AsA accumulation is considered to be controlled by the fine orchestration of net biosynthesis, recycling, degradation/oxidation, and/or intercellular and intracellular transport. To date, several structural genes from the AsA metabolic pathways and transcription factors are considered to significantly affect AsA in plant tissues, either at the level of activity, transcription or translation via feedback inhibition. Yet, all the emerging studies support the notion that the steps proceeding through GDP-L-galactose phosphorylase and to a lesser extent through GDP-D-mannose-3,5-epimerase are control points in governing AsA pool size in several species. In this mini review, we discuss the current consensus of the genetic regulation of AsA biosynthesis and recycling, with a focus on horticultural crops. The aspects of AsA degradation and transport are not discussed herein. Novel insights of how this multifaceted trait is regulated are critical to prioritize candidate genes for follow-up studies toward improving the nutritional value of fruits and vegetables.

MOX fuel reprocessing and recycling

International Nuclear Information System (INIS)

Guillet, J.L.

1990-01-01

This paper is devoted to the reprocessing of MOX fuel in UP2-800 plant at La Hague, and to the MOX successive reprocessing and recycling. 1. MOX fuel reprocessing. In a first step, the necessary modifications in UP2-800 to reprocess MOX fuel are set out. Early in the UP2-800 project, actions have been taken to reprocess MOX fuel without penalty. They consist in measures regarding: Dissolution; Radiological shieldings; Nuclear instrumentation; Criticality. 2. Mox successive reprocessing and recycling. The plutonium recycling in the LWR is now a reality and, as said before, the MOX fuel reprocessing is possible in UP2-800 plant at La Hague. The following actions in this field consist in verifying the MOX successive reprocessing and recycling possibilities. After irradiation, the fissile plutonium content of irradiated MOX fuel is decreased and, in this case, the re-use of plutonium in the LWR need an important increase of initial Pu enrichment inconsistent with the Safety reactor constraints. Cogema opted for reprocessing irradiated MOX fuel in dilution with the standard UO2 fuel in appropriate proportions (1 MOX for 4 UO2 fuel for instance) in order to save a fissile plutonium content compatible with MOX successive recycling (at least 3 recyclings) in LWR. (author). 2 figs

40 CFR 141.76 - Recycle provisions.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Recycle provisions. 141.76 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.76 Recycle provisions. (a... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet...

Auditing Operating Room Recycling: A Management Case Report.

Science.gov (United States)

McGain, Forbes; Jarosz, Katherine Maria; Nguyen, Martin Ngoc Hoai Huong; Bates, Samantha; O'Shea, Catherine Jane

2015-08-01

Much waste arises from operating rooms (ORs). We estimated the practical and financial feasibility of an OR recycling program, weighing all waste from 6 ORs in Melbourne, Australia. Over 1 week, 237 operations produced 1265 kg in total: general waste 570 kg (45%), infectious waste 410 kg (32%), and recyclables 285 kg (23%). The achieved recycling had no infectious contamination. The achieved recycling/potential recycling rate was 285 kg/517 kg (55%). The average waste disposal costs were similar for general waste and recycling. OR recycling rates of 20%-25% total waste were achievable without compromising infection control or financial constraints.

Electric vehicle recycling 2020: Key component power electronics.

Science.gov (United States)

Bulach, Winfried; Schüler, Doris; Sellin, Guido; Elwert, Tobias; Schmid, Dieter; Goldmann, Daniel; Buchert, Matthias; Kammer, Ulrich

2018-04-01

Electromobility will play a key role in order to reach the specified ambitious greenhouse gas reduction targets in the German transport sector of 42% between 1990 and 2030. Subsequently, a significant rise in the sale of electric vehicles (EVs) is to be anticipated in future. The amount of EVs to be recycled will rise correspondingly after a delay. This includes the recyclable power electronics modules which are incorporated in every EV as an important component for energy management. Current recycling methods using car shredders and subsequent post shredder technologies show high recycling rates for the bulk metals but are still associated with high losses of precious and strategic metals such as gold, silver, platinum, palladium and tantalum. For this reason, the project 'Electric vehicle recycling 2020 - key component power electronics' developed an optimised recycling route for recycling power electronics modules from EVs which is also practicable in series production and can be implemented using standardised technology. This 'WEEE recycling route' involves the disassembly of the power electronics from the vehicle and a subsequent recycling in an electronic end-of-life equipment recycling plant. The developed recycling process is economical under the current conditions and raw material prices, even though it involves considerably higher costs than recycling using the car shredder. The life cycle assessment shows basically good results, both for the traditional car shredder route and the developed WEEE recycling route: the latter provides additional benefits from some higher recovery rates and corresponding credits.

Feedwater recycling system in BWR type reactor

International Nuclear Information System (INIS)

Shimamoto, Yoshiharu.

1980-01-01

Purpose: To improve the reactor safety by preventing thermal stresses and cracks generated in structural materials due to the fluctuations in the temperature for high temperature water - low temperature water mixture near the feedwater nozzle. Method: Feedwater pipes are connected to a pressure vessel not directly but by way of a flow control valve. While the recycled water is circulated from an inlet nozzle to an outlet nozzle through a recycle pump, flow control valve and recycling pipeways, feedwater is fed from the feedwater pipes to the recycling pipeways by way of the flow control valve. More specifically, since the high temperature recycle water and the low temperature recycle water are mixed within the pipeways, the temperature fluctuations resulted from the temperature difference between the recycle water and the feedwater is reduced to prevent thermal fatigue and generation of cracks thereby securing the reactor safety. (Furukawa, Y.)

Technology options for future recycling

International Nuclear Information System (INIS)

Kikuchi, T.

2000-01-01

It goes without saying that recycling of nuclear material is indispensable, not only for the effective use of valuable resources but also to reduce the debt which we may leave to the next generations. Many developments in advanced reprocessing technologies have been carried out in several countries to deal with the diversification of nuclear fuels. Also technologies derived from reprocessing or other fuel cycle areas have continued to be developed in terms of recycling. Cost effectiveness and waste-free processing are increasingly important factors in the applicable of an alternate recycling policy. This paper introduces an example of the studies in this field, which has been conducted in Japan and considers the establishment of effective recycling methodologies taking into account the uncertainty of future policy. (authors)

Management options for recycling radioactive scrap metals

Energy Technology Data Exchange (ETDEWEB)

Dehmel, J.C.; MacKinney, J.; Bartlett, J.

1997-02-01

The feasibility and advantages of recycling radioactive scrap metals (RSM) have yet to be assessed, given the unique technical, regulatory, safety, and cost-benefit issues that have already been raised by a concerned recycling industry. As is known, this industry has been repeatedly involved with the accidental recycling of radioactive sources and, in some cases, with costly consequences. If recycling were deemed to be a viable option, it might have to be implemented with regulatory monitoring and controls. Its implementation may have to consider various and complex issues and address the requirements and concerns of distinctly different industries. There are three basic options for the recycling of such scraps. They are: (1) recycling through the existing network of metal-scrap dealers and brokers, (2) recycling directly and only with specific steelmills, or (3) recycling through regional processing centers. Under the first option, scrap dealers and brokers would receive material from RSM generators and determine at which steelmills such scraps would be recycled. For the second option, RSM generators would deal directly with selected steelmills under specific agreements. For the third option, generators would ship scraps only to regional centers for processing and shipment to participating steelmills. This paper addresses the potential advantages of each option, identifies the types of arrangements that would need to be secured among all parties, and attempts to assess the receptivity of the recycling industry to each option.

Exploring metabolic pathway disruption in the subchronic phencyclidine model of schizophrenia with the Generalized Singular Value Decomposition

Directory of Open Access Journals (Sweden)

Morris Brian J

2011-05-01

Encyclopedia of Genes and Genomes (KEGG metabolite pathway database were altered in the PFC of PCP-treated rats. Several significant changes were discovered, notably: 1 neuroactive ligands active at glutamate and GABA receptors are disrupted in the PFC of PCP-treated animals, 2 glutamate dysfunction in these animals was not limited to compromised glutamatergic neurotransmission but also involves the disruption of metabolic pathways linked to glutamate; and 3 a specific series of purine reactions Xanthine ← Hypoxyanthine ↔ Inosine ← IMP → adenylosuccinate is also disrupted in the PFC of PCP-treated animals. Conclusions Network reordering via the GSVD provides a means to discover statistically validated differences in clustering between a pair of networks. In practice this analytical approach, when applied to metabolomic data, allows us to quantify the alterations in metabolic pathways between two experimental groups. With this new computational technique we identified metabolic pathway alterations that are consistent with known results. Furthermore, we discovered disruption in a novel series of purine reactions that may contribute to the PFC dysfunction and cognitive deficits seen in schizophrenia.

Comparison of purine derivatives and creatinine in plasma and urine between local cattle and buffaloes in Vietnam

International Nuclear Information System (INIS)

Vo Thi Kim Thanh; Dao Thi Phuong; Tran Thi Thu Hong; Phung Thi Luu; Ngo Mau Dung; Hoang Quoc Hung; Orskov, E.R.

2004-01-01

In Experiment I, 4 female swamp buffaloes and 4 local cattle fed with the diet based on young maize and rice straw (80/20), and in experiment II, the same number and types of animals as in Experiment I were fed with the diet based on rice straw and rice bran (70/30). The animals were fed twice a day with the diets at 40, 60, 80, 95% of ad libitum intake. The digestibility of nutrients and N excretion were similar for cattle and buffaloes. The purine derivative:creatinine ratio (PDC) index was significantly affected by the level of feed intake (P < 0.001) in both the species. Large differences in urinary purine derivative (PD) excretion were observed, being much lower in buffaloes than in cattle. The regression analysis showed that urinary PD excretion rate per kg of digestible organic matter intake for cattle was higher than that for buffalo. The PDC index also followed the same pattern. The nitrogen retention increased with the supply of energy, both in cattle and buffaloes, indicating that the protein supply was similar. There was no consistent effect of time of day on spot sampling in buffalo and cattle. Buffaloes urinated less frequently than cattle, so sampling time was not really relevant. (author)

Metabolic Interactions of Purine Derivatives with Human ABC Transporter ABCG2: Genetic Testing to Assess Gout Risk.

Science.gov (United States)

Ishikawa, Toshihisa; Aw, Wanping; Kaneko, Kiyoko

2013-11-04

In mammals, excess purine nucleosides are removed from the body by breakdown in the liver and excretion from the kidneys. Uric acid is the end product of purine metabolism in humans. Two-thirds of uric acid in the human body is normally excreted through the kidney, whereas one-third undergoes uricolysis (decomposition of uric acid) in the gut. Elevated serum uric acid levels result in gout and could be a risk factor for cardiovascular disease and diabetes. Recent studies have shown that human ATP-binding cassette transporter ABCG2 plays a role of renal excretion of uric acid. Two non-synonymous single nucleotide polymorphisms (SNPs), i.e., 421C>A (major) and 376C>T (minor), in the ABCG2 gene result in impaired transport activity, owing to ubiquitination-mediated proteosomal degradation and truncation of ABCG2, respectively. These genetic polymorphisms are associated with hyperuricemia and gout. Allele frequencies of those SNPs are significantly higher in Asian populations than they are in African and Caucasian populations. A rapid and isothermal genotyping method has been developed to detect the SNP 421C>A, where one drop of peripheral blood is sufficient for the detection. Development of simple genotyping methods would serve to improve prevention and early therapeutic intervention for high-risk individuals in personalized healthcare.

Recycling of reprocessed uranium

International Nuclear Information System (INIS)

Randl, R.P.

1987-01-01

Since nuclear power was first exploited in the Federal Republic of Germany, the philosophy underlying the strategy of the nuclear fuel cycle has been to make optimum use of the resource potential of recovered uranium and plutonium within a closed fuel cycle. Apart from the weighty argument of reprocessing being an important step in the treatment and disposal of radioactive wastes, permitting their optimum ecological conditioning after the reprocessing step and subsequent storage underground, another argument that, no doubt, carried weight was the possibility of reducing the demand of power plants for natural uranium. In recent years, strategies of recycling have emerged for reprocessed uranium. If that energy potential, too, is to be exploited by thermal recycling, it is appropriate to choose a slightly different method of recycling from the one for plutonium. While the first generation of reprocessed uranium fuel recycled in the reactor cuts down natural uranium requirement by some 15%, the recycling of a second generation of reprocessed, once more enriched uranium fuel helps only to save a further three per cent of natural uranium. Uranium of the second generation already carries uranium-232 isotope, causing production disturbances, and uranium-236 isotope, causing disturbances of the neutron balance in the reactor, in such amounts as to make further fabrication of uranium fuel elements inexpedient, even after mixing with natural uranium feed. (orig./UA) [de

Characterization of quality recycled gypsum and plasterboard with maximized recycled content

International Nuclear Information System (INIS)

Jiménez-Rivero, J.; García-Navarro, J.

2017-01-01

The quality of secondary materials is imperative to promote a circular economy. In order to improve the way in which the quality of recycled gypsum is assessed, European guidelines on recycled gypsum (RG) quality criteria have been outlined in the framework of the Life+ Gypsum to Gypsum (GtoG) project. Such GtoG guidelines, along with the European Standard on gypsum plasterboard EN 520, provided the basis for this study. During the GtoG project, gypsum recycling and plasterboard manufacturing processes were monitored by testing the gypsum feedstock and the plasterboard produced. The aim of this paper is to discuss the results obtained on relevant parameters that characterize gypsum as a secondary raw material, as well as the resulting product. The minimum requirements were fulfilled by 56% of the RG samples and 86% of the plasterboard with increased RG. [es

Synthesis and chemical recycling of high polymers using C1 compounds; C1 kagobutsu ni yoru kobunshi no chemical recycle

Energy Technology Data Exchange (ETDEWEB)

Masuda, T. [National Institute of Materials and Chemical Research, Tsukuba (Japan)

1997-09-01

The paper outlined a study of the synthesis of high polymers using C1 compounds which are continuously usable chemical materials and the related compounds such as the derivatives, and also the chemical recycle. In the case of waste plastics mixed in urban refuse, effective is the chemical recycle where C1 compounds obtained by gasifying the mixed waste are used as high polymer material. For the synthesis and recycle of high polymers using C1 compounds, there are three routes: Route A (recycle via high polymer materials), Route B (recycle via C1 compounds and high polymer materials), and Route C including global-scale carbon recycle (recycle via carbon dioxide from biodegradable plastics using microorganism). Among high polymers, those that can be synthesized from C1 compounds, for example, polymethylene, polyacetal and polyketone can be chemically recycled by Route B. 30 refs., 2 figs., 1 tab.

Roles of the Amino Group of Purine Bases in the Thermodynamic Stability of DNA Base Pairing

Directory of Open Access Journals (Sweden)

Shu-ichi Nakano

2014-08-01

Full Text Available The energetic aspects of hydrogen-bonded base-pair interactions are important for the design of functional nucleotide analogs and for practical applications of oligonucleotides. The present study investigated the contribution of the 2-amino group of DNA purine bases to the thermodynamic stability of oligonucleotide duplexes under different salt and solvent conditions, using 2'-deoxyriboinosine (I and 2'-deoxyribo-2,6-diaminopurine (D as non-canonical nucleotides. The stability of DNA duplexes was changed by substitution of a single base pair in the following order: G•C > D•T ≈ I•C > A•T > G•T > I•T. The apparent stabilization energy due to the presence of the 2-amino group of G and D varied depending on the salt concentration, and decreased in the water-ethanol mixed solvent. The effects of salt concentration on the thermodynamics of DNA duplexes were found to be partially sequence-dependent, and the 2-amino group of the purine bases might have an influence on the binding of ions to DNA through the formation of a stable base-paired structure. Our results also showed that physiological salt conditions were energetically favorable for complementary base recognition, and conversely, low salt concentration media and ethanol-containing solvents were effective for low stringency oligonucleotide hybridization, in the context of conditions employed in this study.

A UK perspective on recycling

International Nuclear Information System (INIS)

Williams, T.

1991-01-01

The United Kingdom, through the recycling of depleted uranium from Magnox reactors into Advanced Gas-cooled Reactor (AGR) fuel, has already recycled significant quantities of reprocessed material in reactors owned by Nuclear Electric plc and Scottish Nuclear Limited. This AGR fuel has been satisfactorily irradiated and discharged over a decade or more, and will be reprocessed in the new Thermal Oxide Reprocessing Plant (THORP), currently under construction in the UK. British Nuclear Fuels plc (BNFL) and the UK Atomic Energy Authority (UKAEA) have also been exploiting the potential of plutonium recycled in mixed oxide (MOX) fuel, which they have been making since 1963. All of the UK nuclear companies are committed to further recycling of Magnox depleted uranium during the 1990s, and it is anticipated that oxide recycling will also become firmly established during the next decade. British Nuclear Fuels and Urenco Ltd, as the providers of fuel cycle services, are developing an infrastructure to close the fuel cycle for oxide nuclear fuel, using both the uranium and plutonium arising from reprocessing. (author)

Infusion of Sibling Marrow in a Patient with Purine Nucleoside Phosphorylase Deficiency Leads to Split Mixed Donor Chimerism and Normal Immunity

Directory of Open Access Journals (Sweden)

Laura Yeates

2017-06-01

Full Text Available Purine nucleoside phosphorylase (PNP deficiency, a rare autosomal recessive metabolic disease causes combined immunodeficiency and developmental delay, hypotonia, and spasticity. Patients present with recurrent infections associated with T-lymphocytopenia, characteristically presenting later than patients with classical severe combined immunodeficiency (SCID. PNP, with adenosine deaminase (ADA, is part of the purine salvage pathway. The only curative therapy is hematopoietic stem cell transplantation. Myeloablative conditioning is recommended to prevent rejection caused by residual immune function. However, HLA-identical sibling stem cell infusions in ADA-SCID result in some donor stem cell engraftment and long-term thymopoiesis. We report a patient with PNP deficiency, who received HLA-identical sibling marrow without chemotherapy because of disseminated cytomegalovirus (CMV infection. The patient presented at 14 months of age following recurrent infections, from early infancy, with persistent irritability, developmental delay, and hypotonia. She had neutropenia, pan-lymphocytopenia, and hypogammaglobulinemia with low plasma urate and erythrocyte PNP activity. Diagnosis was confirmed with a homozygous mutation in PNP. The patient was viremic with CMV detected in blood and CSF by PCR. Dual antiviral therapy improved the clinical condition and reduced the viral load. In view of the disseminated CMV infection, the decision was made to infuse stem cells without any pre-conditioning chemotherapy. She received a matched sibling donor unconditioned stem cell infusion at 16 months of age. The post-transplant course was uneventful. Blood PCR became negative for CMV. Global hypotonia persisted, although with significant improvement in irritability. At 4 years of age and 29 months post-transplant, the patient demonstrated normal T-lymphocyte and natural killer cell numbers. Recent thymic emigrants represented 12% of the total T

Recycling Pressure-Sensitive Products

Science.gov (United States)

Jihui Guo; Larry Gwin; Carl Houtman; Mark Kroll; Steven J. Severtson

2012-01-01

The efficient control of contaminants such as metals, plastics, inks and adhesives during the processing of recovered paper products determines the profitability of recycling mills. In fact, it is arguably the most important technical obstacle in expanding the use of recycled paper.1-4 An especially challenging category of contaminants to manage...

DWPF Recycle Evaporator Simulant Tests

International Nuclear Information System (INIS)

Stone, M

2005-01-01

Testing was performed to determine the feasibility and processing characteristics of an evaporation process to reduce the volume of the recycle stream from the Defense Waste Processing Facility (DWPF). The concentrated recycle would be returned to DWPF while the overhead condensate would be transferred to the Effluent Treatment Plant. Various blends of evaporator feed were tested using simulants developed from characterization of actual recycle streams from DWPF and input from DWPF-Engineering. The simulated feed was evaporated in laboratory scale apparatus to target a 30X volume reduction. Condensate and concentrate samples from each run were analyzed and the process characteristics (foaming, scaling, etc) were visually monitored during each run. The following conclusions were made from the testing: Concentration of the ''typical'' recycle stream in DWPF by 30X was feasible. The addition of DWTT recycle streams to the typical recycle stream raises the solids content of the evaporator feed considerably and lowers the amount of concentration that can be achieved. Foaming was noted during all evaporation tests and must be addressed prior to operation of the full-scale evaporator. Tests were conducted that identified Dow Corning 2210 as an antifoam candidate that warrants further evaluation. The condensate has the potential to exceed the ETP WAC for mercury, silicon, and TOC. Controlling the amount of equipment decontamination recycle in the evaporator blend would help meet the TOC limits. The evaporator condensate will be saturated with mercury and elemental mercury will collect in the evaporator condensate collection vessel. No scaling on heating surfaces was noted during the tests, but splatter onto the walls of the evaporation vessels led to a buildup of solids. These solids were difficult to remove with 2M nitric acid. Precipitation of solids was not noted during the testing. Some of the aluminum present in the recycle streams was converted from gibbsite to

Recycling ampersand incineration: Evaluating the choices

International Nuclear Information System (INIS)

Denison, R.A.; Ruston, J.

1993-01-01

Conflicts between proponents of municipal solid waste incineration and advocates of recycling have escalated with efforts to reduce the volume of waste that ends up in landfills. Central to this debate is competition for materials that are both combustible and recyclable. Environmental and economic concerns also play a major role. This book, produced by the Environmental Defense Fund, compares recycling and incineration. It is intended for 'citizens, government officials, and business people who want to help resolve the solid-waste crisis.' The book is divided into three parts: recycling and incineration; health and environmental risk of incineration; and planning, public participation, and environmental review requirements. The book does an excellent job of discussing the benefits of recycling and the pitfalls of incineration. It provides helpful information for identifying questions that should be raised about incineration, but it does not raise similar queries about recycling. There is much worthwhile information here, but the book would be more useful if it identified critical issues for all waste reduction and management options

Actin-Sorting Nexin 27 (SNX27)-Retromer Complex Mediates Rapid Parathyroid Hormone Receptor Recycling*

Science.gov (United States)

McGarvey, Jennifer C.; Xiao, Kunhong; Bowman, Shanna L.; Mamonova, Tatyana; Zhang, Qiangmin; Bisello, Alessandro; Sneddon, W. Bruce; Ardura, Juan A.; Jean-Alphonse, Frederic; Vilardaga, Jean-Pierre; Puthenveedu, Manojkumar A.; Friedman, Peter A.

2016-01-01

The G protein-coupled parathyroid hormone receptor (PTHR) regulates mineral-ion homeostasis and bone remodeling. Upon parathyroid hormone (PTH) stimulation, the PTHR internalizes into early endosomes and subsequently traffics to the retromer complex, a sorting platform on early endosomes that promotes recycling of surface receptors. The C terminus of the PTHR contains a type I PDZ ligand that binds PDZ domain-containing proteins. Mass spectrometry identified sorting nexin 27 (SNX27) in isolated endosomes as a PTHR binding partner. PTH treatment enriched endosomal PTHR. SNX27 contains a PDZ domain and serves as a cargo selector for the retromer complex. VPS26, VPS29, and VPS35 retromer subunits were isolated with PTHR in endosomes from cells stimulated with PTH. Molecular dynamics and protein binding studies establish that PTHR and SNX27 interactions depend on the PDZ recognition motif in PTHR and the PDZ domain of SNX27. Depletion of either SNX27 or VPS35 or actin depolymerization decreased the rate of PTHR recycling following agonist stimulation. Mutating the PDZ ligand of PTHR abolished the interaction with SNX27 but did not affect the overall rate of recycling, suggesting that PTHR may directly engage the retromer complex. Coimmunoprecipitation and overlay experiments show that both intact and mutated PTHR bind retromer through the VPS26 protomer and sequentially assemble a ternary complex with PTHR and SNX27. SNX27-independent recycling may involve N-ethylmaleimide-sensitive factor, which binds both PDZ intact and mutant PTHRs. We conclude that PTHR recycles rapidly through at least two pathways, one involving the ASRT complex of actin, SNX27, and retromer and another possibly involving N-ethylmaleimide-sensitive factor. PMID:27008860

Encouraging Vietnamese Household Recycling Behavior: Insights and Implications

Directory of Open Access Journals (Sweden)

The Ninh Nguyen

2017-01-01

Full Text Available This research aims to provide new insights into various determinants affecting household recycling. By focusing on Vietnam, this research also extends knowledge about sustainable behavior in emerging markets, which are the major culprits in terms of greenhouse gas emissions. Hypotheses were developed as a result of the critical review of relevant studies in the fields of marketing, psychology, and economics, and then tested using a quantitative survey data. Structured questionnaires were administered to Vietnamese respondents which yielded 486 usable responses. Multivariate statistics reveal that all the determinants influenced their recycling behavior except for moral norms. Attitude towards the importance of recycling exerted the strongest influence, followed by subjective norms and warm glow respectively. On the other hand, attitude towards the inconvenience of recycling significantly reduced recycling behavior. The research findings have important implications for strategies aimed at promoting recycling behavior. Communication and education programs should emphasize how household recycling contributes to environmental protection, as well as stress intrinsic rewards when recycling. Public media campaigns should feature opinion leaders and attractive communicators, who can effectively apply social pressure to perform recycling behavior. Organizations should also make every effort to make recycling more convenient.

The immunosuppressives FK 506 and cyclosporin A inhibit the generation of protein factors binding to the two purine boxes of the interleukin 2 enhancer.

Science.gov (United States)

Brabletz, T; Pietrowski, I; Serfling, E

1991-01-11

Like Cyclosporin A (CsA), the macrolide FK 506 is a potent immunosuppressive that inhibits early steps of T cell activation, including the synthesis of Interleukin 2 (II-2) and numerous other lymphokines. The block of II-2 synthesis occurs at the transcriptional level. At concentrations that block T cell activation, FK 506 and CsA inhibit the proto-enhancer activity of Purine boxes of the II-2 promoter and the generation of lymphocyte-specific factors binding to the Purine boxes. Under the same conditions, the DNA binding of other II-2 enhancer factors remains unaffected by both compounds. These results support the view that FK 506 and CsA, which both inhibit the activity of peptidylprolyl cis/trans isomerases, suppress T cell activation by a similar, if not identical mechanism.

Antimony recycling in the United States in 2000

Science.gov (United States)

Carlin, James F.

2006-01-01

The importance of recycling has become more obvious as concerns about the environment and import dependence have grown in recent years. When materials are recycled, fewer natural resources are consumed, and less waste products go to landfills or pollute the water and air. This study, one of a series of reports on metals recycling in 2000, discusses the flow of antimony from mining through its uses and disposal with emphasis on recycling. In 2000, the recycling efficiency for antimony was estimated to be 89 percent, and the recycling rate was about 20 percent.

Design study on advanced nuclear fuel recycle system. Conceptual design study of recycle system using molten salt

International Nuclear Information System (INIS)

Kasai, Y.; Kakehi, I.; Moro, T.; Higashi, T.; Tobe, K.; Kawamura, F.; Yonezawa, S.; Yoshiuji, T.

1998-10-01

Advanced recycle system engineering group of OEC (Oarai Engineering Center) has being carried out a design study of the advanced nuclear fuel recycle system using molten salt (electro-metallurgical process). This system is aiming for improvements of fuel cycle economy and reduction of environmental burden (MA recycles, Minimum of radioactive waste disposal), and also improvement of safety and nuclear non-proliferation. This report describes results of the design study that has been continued since December 1996. (1) A design concept of the advanced nuclear fuel recycle system, that is a module type recycles system of pyrochemical reprocessing and fuel re-fabrication was studied. The module system has advantage in balance of Pu recycle where modules are constructed in coincidence with the construction plan of nuclear power plants, and also has flexibility for technology progress. A demonstration system, minimum size of the above module, was studies. This system has capacity of 10 tHM/y and is able to demonstrate recycle technology of MOX fuel, metal fuel and nitride fuel. (2) Each process of the system, which are pyrochemical electrorefining system, cathode processor, de-cladding system, waste disposal system, etc., were studied. In this study, capacity of an electrorefiner was discussed, and vitrification experiment of molten salt using lead-boric acid glass was conducted. (3) A hot cell system and material handling system of the demonstration system was studied. A robot driven by linear motor was studied for the handling system, and an arrangement plan of the cell system was made. Criticality analysis in the cell system and investigation of material accountancy system of the recycle plant were also made. This design study will be continued in coincidence with design study of reactor and fuel, aiming to establish the concept of FBR recycle system. (author)

The Purine Bias of Coding Sequences is Determined by Physicochemical Constraints on Proteins.

Science.gov (United States)

Ponce de Leon, Miguel; de Miranda, Antonio Basilio; Alvarez-Valin, Fernando; Carels, Nicolas

2014-01-01

For this report, we analyzed protein secondary structures in relation to the statistics of three nucleotide codon positions. The purpose of this investigation was to find which properties of the ribosome, tRNA or protein level, could explain the purine bias (Rrr) as it is observed in coding DNA. We found that the Rrr pattern is the consequence of a regularity (the codon structure) resulting from physicochemical constraints on proteins and thermodynamic constraints on ribosomal machinery. The physicochemical constraints on proteins mainly come from the hydropathy and molecular weight (MW) of secondary structures as well as the energy cost of amino acid synthesis. These constraints appear through a network of statistical correlations, such as (i) the cost of amino acid synthesis, which is in favor of a higher level of guanine in the first codon position, (ii) the constructive contribution of hydropathy alternation in proteins, (iii) the spatial organization of secondary structure in proteins according to solvent accessibility, (iv) the spatial organization of secondary structure according to amino acid hydropathy, (v) the statistical correlation of MW with protein secondary structures and their overall hydropathy, (vi) the statistical correlation of thymine in the second codon position with hydropathy and the energy cost of amino acid synthesis, and (vii) the statistical correlation of adenine in the second codon position with amino acid complexity and the MW of secondary protein structures. Amino acid physicochemical properties and functional constraints on proteins constitute a code that is translated into a purine bias within the coding DNA via tRNAs. In that sense, the Rrr pattern within coding DNA is the effect of information transfer on nucleotide composition from protein to DNA by selection according to the codon positions. Thus, coding DNA structure and ribosomal machinery co-evolved to minimize the energy cost of protein coding given the functional

Filter Backwash Recycling Rule Documents

Science.gov (United States)

The purpose of the FBRR is to require (PWSs) to review their recycle practices and, where appropriate, work with the state Primacy Agency to make any necessary changes to recycle practices that may compromise microbial control.

A pilot study on genetic variation in purine-rich elements in the nephrin gene promoter in type 2 diabetic patients

Directory of Open Access Journals (Sweden)

RODRIGO GONZÁLEZ

2007-01-01

Full Text Available Diabetic nephropathy (DN is one of the major complications of type 2 diabetes and is associated with coronary disease. Nephrin, a protein mainly expressed in glomeruli, is decreased in DN and other kidney diseases. Since insulin levels are misregulated in type 2 diabetes, a possible connection between DN and its decreased nephrin expression could be the presence of regulatory elements responsive to insulin in the nephrin gene (NPHS1 promoter region. In this work, using bioinformatic tools, we identified a purine-rich GAGA element in the nephrin gene promoter and conducted a genomic study in search of the presence of polymorphisms in this element and its possible association with DN in type 2 diabetic patients. We amplified and sequenced a 514 bp promoter region of 100 individuals and found no genetic variants in the purine-rich GAGA-box of the nephrin gene promoter between groups of patients with diabetes type 2 with and without renal and coronary complications, control patients without diabetes and healthy controls

Coal liquefaction with preasphaltene recycle

Science.gov (United States)

Weimer, Robert F.; Miller, Robert N.

1986-01-01

A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

Overview of HTGR fuel recycle

International Nuclear Information System (INIS)

Notz, K.J.

1976-01-01

An overview of HTGR fuel recycle is presented, with emphasis placed on reprocessing and fuel kernel refabrication. Overall recycle operations include (1) shipment and storage, (2) reprocessing, (3) refabrication, (4) waste handling, and (5) accountability and safeguards

Sustaining the environment through recycling: an empirical study.

Science.gov (United States)

Ramayah, T; Lee, Jason Wai Chow; Lim, Shuwen

2012-07-15

This paper examines the determinants of recycling behaviour among 200 university students from the perspective of the theory of planned behaviour (TPB). Data was analysed using Structural Equation Modelling technique. Findings indicate that environmental awareness was significantly related to attitude towards recycling, whilst attitude and social norms had significant impact on recycling behaviour. However, convenience and cost of recycling were not significant reasons for recycling. The study has enhanced the understanding of the determinants of recycling behaviour and has implications for schools and governmental agencies in educating and encouraging positive recycling behaviour. It also confirms the appropriateness of the TPB in examining studies of this nature. Further suggestions for future research are offered. Copyright © 2012 Elsevier Ltd. All rights reserved.

Recycling fusion materials

International Nuclear Information System (INIS)

Ooms, L.

2005-01-01

The inherent safety and environmental advantages of fusion power in comparison with other energy sources play an important role in the public acceptance. No waste burden for future generations is therefore one of the main arguments to decide for fusion power. The waste issue has thus been studied in several documents and the final conclusion of which it is stated that there is no permanent disposal waste needed if recycling is applied. But recycling of fusion reactor materials is far to be obvious regarding mostly the very high specific activity of the materials to be handled, the types of materials and the presence of tritium. The main objective of research performed by SCK-CEN is to study the possible ways of recycling fusion materials and analyse the challenges of the materials management from fusion reactors, based on current practices used in fission reactors and the requirements for the manufacture of fusion equipment

National plan for the radioactive and recyclable wastes management of the national inventory of the radioactive and recyclable wastes to an account and a prospective outlook of the pathways of long dated management of radioactive wastes in France; Plan national de gestion des dechets radioactifs et des matieres valorisables de l'inventaire national des dechets radioactifs et des matieres valorisable a un bilan et une vision prospective des filieres de gestion a long terme des dechets radioactifs en France

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-15

The introduction recalls the context of the development of the national plan of radioactive and recyclable wastes management (PNGDR-MV), its objectives and its position in the today studies on radioactive wastes. The first part is devoted to the description of existing radioactive wastes management solutions, or engaged by today activities. The second part concerns the radioactive materials of the nuclear industry, which are not considered as wastes, but which can be recyclable because of their high energy potential as fuels for reactors of the future. The third part examines the pathways coherence. The last part is a synthesis of the evaluation, with more attention on the identifies problems. (A.L.B.)

Recycling of polymers: a review.

Science.gov (United States)

Ignatyev, Igor A; Thielemans, Wim; Vander Beke, Bob

2014-06-01

Plastics are inexpensive, easy to mold, and lightweight. These and many other advantages make them very promising candidates for commercial applications. In many areas, they have substantially suppressed traditional materials. However, the problem of recycling still is a major challenge. There are both technological and economic issues that restrain the progress in this field. Herein, a state-of-art overview of recycling is provided together with an outlook for the future by using popular polymers such as polyolefins, poly(vinyl chloride), polyurethane, and poly(ethylene terephthalate) as examples. Different types of recycling, primary, secondary, tertiary, quaternary, and biological recycling, are discussed together with related issues, such as compatibilization and cross-linking. There are various projects in the European Union on research and application of these recycling approaches; selected examples are provided in this article. Their progress is mirrored by granted patents, most of which have a very limited scope and narrowly cover certain technologies. Global introduction of waste utilization techniques to the polymer market is currently not fully developed, but has an enormous potential. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Long-term aging of recycled binders : [summary].

Science.gov (United States)

2015-10-01

At 80 million tons a year representing more than 80% of all milled asphalt pavement : asphalt paving is Americas most recycled material. Asphalt can be recycled in place, which is : very cost effective; however, aging of recycled binder ca...

Waste management considerations in HTGR recycle operations

International Nuclear Information System (INIS)

Pence, D.T.; Shefcik, J.J.; Heath, C.A.

1975-01-01

Waste management considerations in the recycle of HTGR fuel are different from those encountered in the recycle of LWR fuel. The types of waste associated with HTGR recycle operations are discussed, and treatment methods for some of the wastes are described

Interpretation of substituent effects on 13C and 15N NMR chemical shifts in 6-substituted purines

Czech Academy of Sciences Publication Activity Database

Standara, Stanislav; Bouzková, K.; Straka, Michal; Zacharová, Z.; Hocek, Michal; Marek, J.; Marek, R.

2011-01-01

Roč. 13, č. 35 (2011), s. 15854-15864 ISSN 1463-9076 R&D Projects: GA ČR GA203/09/2037 Grant - others:CEITEC(XE) CZ.1.05/1.1.00/02.0068; 7th European Community Framework (XE) 230955; GA MŠk(CZ) LC06030 Program:LC Institutional research plan: CEZ:AV0Z40550506 Keywords : purine * nuclear magnetic shielding * localized molecular orbitals * conformational dependence Subject RIV: CC - Organic Chemistry Impact factor: 3.573, year: 2011

Molecular and biochemical characterization of caffeine synthase and purine alkaloid concentration in guarana fruit.

Science.gov (United States)

Schimpl, Flávia Camila; Kiyota, Eduardo; Mayer, Juliana Lischka Sampaio; Gonçalves, José Francisco de Carvalho; da Silva, José Ferreira; Mazzafera, Paulo

2014-09-01

Guarana seeds have the highest caffeine concentration among plants accumulating purine alkaloids, but in contrast with coffee and tea, practically nothing is known about caffeine metabolism in this Amazonian plant. In this study, the levels of purine alkaloids in tissues of five guarana cultivars were determined. Theobromine was the main alkaloid that accumulated in leaves, stems, inflorescences and pericarps of fruit, while caffeine accumulated in the seeds and reached levels from 3.3% to 5.8%. In all tissues analysed, the alkaloid concentration, whether theobromine or caffeine, was higher in young/immature tissues, then decreasing with plant development/maturation. Caffeine synthase activity was highest in seeds of immature fruit. A nucleotide sequence (PcCS) was assembled with sequences retrieved from the EST database REALGENE using sequences of caffeine synthase from coffee and tea, whose expression was also highest in seeds from immature fruit. The PcCS has 1083bp and the protein sequence has greater similarity and identity with the caffeine synthase from cocoa (BTS1) and tea (TCS1). A recombinant PcCS allowed functional characterization of the enzyme as a bifunctional CS, able to catalyse the methylation of 7-methylxanthine to theobromine (3,7-dimethylxanthine), and theobromine to caffeine (1,3,7-trimethylxanthine), respectively. Among several substrates tested, PcCS showed higher affinity for theobromine, differing from all other caffeine synthases described so far, which have higher affinity for paraxanthine. When compared to previous knowledge on the protein structure of coffee caffeine synthase, the unique substrate affinity of PcCS is probably explained by the amino acid residues found in the active site of the predicted protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

Concrete Waste Recycling Process for High Quality Aggregate

International Nuclear Information System (INIS)

Ishikura, Takeshi; Fujii, Shin-ichi

2008-01-01

Large amount of concrete waste generates during nuclear power plant (NPP) dismantling. Non-contaminated concrete waste is assumed to be disposed in a landfill site, but that will not be the solution especially in the future, because of decreasing tendency of the site availability and natural resources. Concerning concrete recycling, demand for roadbeds and backfill tends to be less than the amount of dismantled concrete generated in a single rural site, and conventional recycled aggregate is limited of its use to non-structural concrete, because of its inferior quality to ordinary natural aggregate. Therefore, it is vital to develop high quality recycled aggregate for general uses of dismantled concrete. If recycled aggregate is available for high structural concrete, the dismantling concrete is recyclable as aggregate for industry including nuclear field. Authors developed techniques on high quality aggregate reclamation for large amount of concrete generated during NPP decommissioning. Concrete of NPP buildings has good features for recycling aggregate; large quantity of high quality aggregate from same origin, record keeping of the aggregate origin, and little impurities in dismantled concrete such as wood and plastics. The target of recycled aggregate in this development is to meet the quality criteria for NPP concrete as prescribed in JASS 5N 'Specification for Nuclear Power Facility Reinforced Concrete' and JASS 5 'Specification for Reinforced Concrete Work'. The target of recycled aggregate concrete is to be comparable performance with ordinary aggregate concrete. The high quality recycled aggregate production techniques are assumed to apply for recycling for large amount of non-contaminated concrete. These techniques can also be applied for slightly contaminated concrete dismantled from radiological control area (RCA), together with free release survey. In conclusion: a technology on dismantled concrete recycling for high quality aggregate was developed

What do we know about metal recycling rates?

Science.gov (United States)

Graedel, T.E.; Allwood, J.; Birat, J.-P.; Buchert, M.; Hageluken, C.; Reck, B.K.; Sibley, S.F.; Sonnemann, G.

2011-01-01

The recycling of metals is widely viewed as a fruitful sustainability strategy, but little information is available on the degree to which recycling is actually taking place. This article provides an overview on the current knowledge of recycling rates for 60 metals. We propose various recycling metrics, discuss relevant aspects of recycling processes, and present current estimates on global end-of-life recycling rates (EOL-RR; i.e., the percentage of a metal in discards that is actually recycled), recycled content (RC), and old scrap ratios (OSRs; i.e., the share of old scrap in the total scrap flow). Because of increases in metal use over time and long metal in-use lifetimes, many RC values are low and will remain so for the foreseeable future. Because of relatively low efficiencies in the collection and processing of most discarded products, inherent limitations in recycling processes, and the fact that primary material is often relatively abundant and low-cost (which thereby keeps down the price of scrap), many EOL-RRs are very low: Only for 18 metals (silver, aluminum, gold, cobalt, chromium, copper, iron, manganese, niobium, nickel, lead, palladium, platinum, rhenium, rhodium, tin, titanium, and zinc) is the EOL-RR above 50% at present. Only for niobium, lead, and ruthenium is the RC above 50%, although 16 metals are in the 25% to 50% range. Thirteen metals have an OSR greater than 50%. These estimates may be used in considerations of whether recycling efficiencies can be improved; which metric could best encourage improved effectiveness in recycling; and an improved understanding of the dependence of recycling on economics, technology, and other factors. ?? 2011 by Yale University.

Energetic conditions of effective recycling of composite castings

OpenAIRE

J. Jackowski

2009-01-01

The most reasonable way of recycling the metal composite materials consists in separation of the components. In case of the composites with saturated reinforcement it is the only recycling method. The process of separation of the components always undergoes in the presence of an additional liquid phase called a recycling medium. In a three-phase system including the material of composite reinforcement – liquid composite matrix – liquid recycling medium, an important role for the recycling pro...

Is Municipal Solid Waste Recycling Economically Efficient?

Science.gov (United States)

Lavee, Doron

2007-12-01

It has traditionally been argued that recycling municipal solid waste (MSW) is usually not economically viable and that only when externalities, long-term dynamic considerations, and/or the entire product life cycle are taken into account, recycling becomes worthwhile from a social point of view. This article explores the results of a wide study conducted in Israel in the years 2000 2004. Our results reveal that recycling is optimal more often than usually claimed, even when externality considerations are ignored. The study is unique in the tools it uses to explore the efficiency of recycling: a computer-based simulation applied to an extensive database. We developed a simulation for assessing the costs of handling and treating MSW under different waste-management systems and used this simulation to explore possible cost reductions obtained by designating some of the waste (otherwise sent to landfill) to recycling. We ran the simulation on data from 79 municipalities in Israel that produce over 60% of MSW in Israel. For each municipality, we were able to arrive at an optimal method of waste management and compare the costs associated with 100% landfilling to the costs born by the municipality when some of the waste is recycled. Our results indicate that for 51% of the municipalities, it would be efficient to adopt recycling, even without accounting for externality costs. We found that by adopting recycling, municipalities would be able to reduce direct costs by an average of 11%. Through interviews conducted with representatives of municipalities, we were also able to identify obstacles to the utilization of recycling, answering in part the question of why actual recycling levels in Israel are lower than our model predicts they should be.

Wobble↔Watson-Crick tautomeric transitions in the homo-purine DNA mismatches: a key to the intimate mechanisms of the spontaneous transversions.

Science.gov (United States)

Brovarets', Ol'ha O; Hovorun, Dmytro M

2015-01-01

The intrinsic capability of the homo-purine DNA base mispairs to perform wobble↔Watson-Crick/Topal-Fresco tautomeric transitions via the sequential intrapair double proton transfer was discovered for the first time using QM (MP2/DFT) and QTAIM methodologies that are crucial for understanding the microstructural mechanisms of the spontaneous transversions.

India's ship recycling trade-off

NARCIS (Netherlands)

Worrell, E.; Athanasopoulou, V.

2014-01-01

The special nature of India's steel industry lends particular importance to ship recycling as a source of scrap. Ship recycling in upgraded 'green' facilities can substitute other 'dirty' ironmaking processes, resulting in energy savings and air pollutant emission reductions for the Indian steel

Extracellular Purine Metabolism Is the Switchboard of Immunosuppressive Macrophages and a Novel Target to Treat Diseases With Macrophage Imbalances

Directory of Open Access Journals (Sweden)

Anna Ohradanova-Repic

2018-04-01

Full Text Available If misregulated, macrophage (Mϕ–T cell interactions can drive chronic inflammation thereby causing diseases, such as rheumatoid arthritis (RA. We report that in a proinflammatory environment, granulocyte-Mϕ (GM-CSF- and Mϕ colony-stimulating factor (M-CSF-dependent Mϕs have dichotomous effects on T cell activity. While GM-CSF-dependent Mϕs show a highly stimulatory activity typical for M1 Mϕs, M-CSF-dependent Mϕs, marked by folate receptor β (FRβ, adopt an immunosuppressive M2 phenotype. We find the latter to be caused by the purinergic pathway that directs release of extracellular ATP and its conversion to immunosuppressive adenosine by co-expressed CD39 and CD73. Since we observed a misbalance between immunosuppressive and immunostimulatory Mϕs in human and murine arthritic joints, we devised a new strategy for RA treatment based on targeted delivery of a novel methotrexate (MTX formulation to the immunosuppressive FRβ+CD39+CD73+ Mϕs, which boosts adenosine production and curtails the dominance of proinflammatory Mϕs. In contrast to untargeted MTX, this approach leads to potent alleviation of inflammation in the murine arthritis model. In conclusion, we define the Mϕ extracellular purine metabolism as a novel checkpoint in Mϕ cell fate decision-making and an attractive target to control pathological Mϕs in immune-mediated diseases.

Mox fuels recycling

International Nuclear Information System (INIS)

Gay, A.

1998-01-01

This paper will firstly emphasis that the first recycling of plutonium is already an industrial reality in France thanks to the high degree of performance of La Hague and MELOX COGEMA's plants. Secondly, recycling of spent Mixed OXide fuel, as a complete MOX fuel cycle, will be demonstrated through the ability of the existing plants and services which have been designed to proceed with such fuels. Each step of the MOX fuel cycle concept will be presented: transportation, reception and storage at La Hague and steps of spent MOX fuel reprocessing. (author)

Recycling of Reinforced Plastics

Science.gov (United States)

Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

2014-02-01

This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

Metabolic Interactions of Purine Derivatives with Human ABC Transporter ABCG2: Genetic Testing to Assess Gout Risk

Directory of Open Access Journals (Sweden)

Kiyoko Kaneko

2013-11-01

Full Text Available In mammals, excess purine nucleosides are removed from the body by breakdown in the liver and excretion from the kidneys. Uric acid is the end product of purine metabolism in humans. Two-thirds of uric acid in the human body is normally excreted through the kidney, whereas one-third undergoes uricolysis (decomposition of uric acid in the gut. Elevated serum uric acid levels result in gout and could be a risk factor for cardiovascular disease and diabetes. Recent studies have shown that human ATP-binding cassette transporter ABCG2 plays a role of renal excretion of uric acid. Two non-synonymous single nucleotide polymorphisms (SNPs, i.e., 421C>A (major and 376C>T (minor, in the ABCG2 gene result in impaired transport activity, owing to ubiquitination-mediated proteosomal degradation and truncation of ABCG2, respectively. These genetic polymorphisms are associated with hyperuricemia and gout. Allele frequencies of those SNPs are significantly higher in Asian populations than they are in African and Caucasian populations. A rapid and isothermal genotyping method has been developed to detect the SNP 421C>A, where one drop of peripheral blood is sufficient for the detection. Development of simple genotyping methods would serve to improve prevention and early therapeutic intervention for high-risk individuals in personalized healthcare.

Bicarbonate-regulated adenylyl cyclase (sAC) is a sensor that regulates pH-dependent V-ATPase recycling.

Science.gov (United States)

Pastor-Soler, Nuria; Beaulieu, Valerie; Litvin, Tatiana N; Da Silva, Nicolas; Chen, Yanqiu; Brown, Dennis; Buck, Jochen; Levin, Lonny R; Breton, Sylvie

2003-12-05

Modulation of environmental pH is critical for the function of many biological systems. However, the molecular identity of the pH sensor and its interaction with downstream effector proteins remain poorly understood. Using the male reproductive tract as a model system in which luminal acidification is critical for sperm maturation and storage, we now report a novel pathway for pH regulation linking the bicarbonate activated soluble adenylyl cyclase (sAC) to the vacuolar H+ATPase (V-ATPase). Clear cells of the epididymis and vas deferens contain abundant V-ATPase in their apical pole and are responsible for acidifying the lumen. Proton secretion is regulated via active recycling of V-ATPase. Here we demonstrate that this recycling is regulated by luminal pH and bicarbonate. sAC is highly expressed in clear cells, and apical membrane accumulation of V-ATPase is triggered by a sAC-dependent rise in cAMP in response to alkaline luminal pH. As sAC is expressed in other acid/base transporting epithelia, including kidney and choroid plexus, this cAMP-dependent signal transduction pathway may be a widespread mechanism that allows cells to sense and modulate extracellular pH.

76 FR 71861 - America Recycles Day, 2011

Science.gov (United States)

2011-11-18

... electronics annually, and without following proper recycling and management practices, the disposal of our old..., and prevent the recovery and reuse of valuable resources. For the well- being of our people and our..., management, and recycling that will accelerate our burgeoning electronics recycling market and create jobs...

On the logistics of recycling : an introduction

NARCIS (Netherlands)

Flapper, S.D.P.

1993-01-01

An overview is given of the different logistic aspects of recycling, where recycling denotes "All the activities required for the reuse of materials and (semi-)finished products after they are no longer used by their last user." Special attention is paid to the forced recycling of durable

Hydrogen recycle modeling in transport codes

International Nuclear Information System (INIS)

Howe, H.C.

1979-01-01

The hydrogen recycling models now used in Tokamak transport codes are reviewed and the method by which realistic recycling models are being added is discussed. Present models use arbitrary recycle coefficients and therefore do not model the actual recycling processes at the wall. A model for the hydrogen concentration in the wall serves two purposes: (1) it allows a better understanding of the density behavior in present gas puff, pellet, and neutral beam heating experiments; and (2) it allows one to extrapolate to long pulse devices such as EBT, ISX-C and reactors where the walls are observed or expected to saturate. Several wall models are presently being studied for inclusion in transport codes

The PurR regulon in Lactococcus lactis – transcriptional regulation of the purine nucleotide metabolism and translational machinery

DEFF Research Database (Denmark)

Jendresen, Christian Bille; Martinussen, Jan; Kilstrup, Mogens

2012-01-01

Purine nucleotides are either synthesized de novo from 5-phosphoribosyl-1-pyrophosphate (PRPP) or salvaged from the environment. In Lactococcus lactis, transcription of the de novo synthesis operons, purCSQLF and purDEK, has genetically been shown to be activated by the PurR protein when bound to......-related functions. Of special interest is the presence of PurBox motifs in rrn promoters, suggesting a novel connection between nucleotide availability and the translational machinery....

Recycling of nonferrous metals from waste materials

Energy Technology Data Exchange (ETDEWEB)

Urban, A

1982-02-01

Recycling of metals was one of the 9 central subjects of the international symposium on 'Materials and Energy from Refuse', held in Antwerpen on October 20 to 22, 1981. Six of 65 poster sessions papers were on metal recycling; four of them discussed the recycling of nonferrous metals.

Recycling behaviour in healthcare: waste handling at work.

Science.gov (United States)

Vogt, Joachim; Nunes, Katia R A

2014-01-01

This article reviews the motivational factors for environmental behaviour in general, presenting a case study on recycling disposable plastics in hospitals. Results show that 90% of over 600 employees from six analysed hospitals in Germany reported that the recycling of disposable plastics on the wards makes sense from an environmental and economic point of view. The case study reports an assessment of recycling attitudes and problems of hospital staff, mainly nurses. Employees in eco-certified hospitals were much more satisfied and reported fewer problems with the recycling system. The gender effect was significant only for saving energy, while age correlated with nearly all reported pro-environmental behaviour at home. At work, the mere introduction of a recycling system was insufficient to achieve good recycling results. Based on the study findings, recommendations are given aimed at improving the safety and sustainability of the recycling system.

Space Plastic Recycling System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Techshot's proposed Space Plastic Recycler (SPR) is an automated closed loop plastic recycling system that allows the automated conversion of disposable ISS...

Probabilistic Analysis of Structural Member from Recycled Aggregate Concrete

Science.gov (United States)

Broukalová, I.; Šeps, K.

2017-09-01

The paper aims at the topic of sustainable building concerning recycling of waste rubble concrete from demolition. Considering demands of maximising recycled aggregate use and minimising of cement consumption, composite from recycled concrete aggregate was proposed. The objective of the presented investigations was to verify feasibility of the recycled aggregate cement based fibre reinforced composite in a structural member. Reliability of wall from recycled aggregate fibre reinforced composite was assessed in a probabilistic analysis of a load-bearing capacity of the wall. The applicability of recycled aggregate fibre reinforced concrete in structural applications was demonstrated. The outcomes refer to issue of high scatter of material parameters of recycled aggregate concretes.

Bottle & Can Recycling in Denmark: addressing issues and optimizing the recycling rate

OpenAIRE

Carnevale, Alessandro; Larsen, Lucas; Tetens, Simon W.

2015-01-01

The research is conducted in the landscape of environmental care and consumer behaviour. This paper explores the different dynamics revolving around the recycling of plastic bottles and aluminium cans in Denmark. The aim is to shed light on the possible impediments people might encounter when attempting to hand back their deposit marked bottle to the allocated facilities as well as illuminating what the main forces involved in encouraging or inhibiting people from recycling are. The ultimate ...

Economics and recycling

Energy Technology Data Exchange (ETDEWEB)

Butlin, J A

1977-06-01

The current state of recycling technology could appear to be a question of supply and demand, first for storage, disposal, and reclamation facilities, and secondly, for reclaimed materials. If supply and demand are to be relied upon as an environmental policy tool, several conditions need to exist within the economy: supply data for storage and disposal facilities should reflect the full social cost of their use for this purpose relative to any other; demand data for the use of storage facilities must reflect the full social benefit of having waste go through one channel rather than some other; demand for and supply of reclaimed materials for recycling must reflect the full costs and benefits of rechanneling them back into production or consumption; and the markets for products competitive to recycled raw materials (mainly virgin raw materials) should reflect full social costs and benefits, as should the markets for the alternative uses of storage and disposal facilities. If these conditions are met (in addition to a few technical ones), then the problem of waste management will not arise. (MCW)

The Recycler Electron Cooler

Energy Technology Data Exchange (ETDEWEB)

Shemyakin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Prost, L. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

2013-03-19

The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters and the ways to overcome them, cooling measurements, and details of operation.

Tire recycling technologies: What is the future?

NARCIS (Netherlands)

Saiwari, Sitisaiyidah; van Hoek, Johannes Wilhelmus; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.; Blume, Anke; Heideman, G.

2016-01-01

Recycling is a heavily discussed topic nowadays, and recycled tire material to be re-used for the same application is one of the spear points of current R&D activities. Regarding the immense amount of used tires, more than just one outlet for the recycled material is needed. Besides the commonly

Fluorescent lamp recycling initiatives in the United States and a recycling proposal based on extended producer responsibility and product stewardship concepts.

Science.gov (United States)

Silveira, Geraldo Tr; Chang, Shoou-Yuh

2011-06-01

This paper presents an overview of mercury-containing lamp (MCL) recycling initiatives currently available in the world, especially in the United States. The majority of MCLs contain mercury which is a neurotoxin, a persistent pollutant in the environment, and can bioaccumulate in the food chain. Although there are some recycling options in the United States, collection rates are still at 23% of all potential used MCLs. This shows that citizens are either indifferent to or unaware of the recycling alternatives. On the other hand, MCL recycling seems not to be a cost-effective process and, for this reason, in the United States, take-back programmes are still sponsored only by consumers or municipalities. A few retailers have recently initiated limited take-back alternatives and manufacturers have not yet supported financially any consistent recycling alternative in the country. Considering successful experiences, this paper makes a suggestion for an MCL recycling system based on the concepts of extended producer responsibility and product stewardship. A manufacturer-importer advance recycling fee is proposed to finance the collection and recycling system while a MCL-energy recycling fee supported by the energy sector creates a lamp refund process. 'PRO Lamp', a producer responsibility organization, will manage the entire system through a widespread public-private agreement.

Quantify the energy and environmental effects of using recycled asphalt and recycled concrete for pavement construction phase I : final report.

Science.gov (United States)

2009-08-01

The objective of this study is to quantify the energy and environment impacts from using recycled materials : for highway construction. Specifically, when recycled asphalt pavement is re-used for producing hot mix : asphalt or when recycled concrete ...

Biodegradation pathway of an anionic surfactant (Igepon TC-42) during recycling waste water through plant hydroponics for advanced life support during long-duration space missions

Science.gov (United States)

Levine, L. H.; Kagie, H. R.; Garland, J. L.

The degradation of an anionic surfactant (Igepon TC-42) was investigated as part of an integrated study of direct recycling of human hygiene water through hydroponic plant growth systems. Several chemical approaches were developed to characterize the degradation of Igepon and to measure the accumulation of intermediates such as fatty acids and methyl taurine. Igepon was rapidly degraded as indicated by the reduction of methylene blue active substances (MBAS) and component fatty acids. The Igepon degradation rate continued to increase over a period of several weeks following repeated daily exposure to 18 μg/l Igepon. The accumulation of free fatty acids and methyl taurine was also observed during decomposition of Igepon. The concentration of methyl taurine was below detection limit (0.2 nmol/ml) during the slow phase of Igepon degradation, and increased to 1-2 nmol/ml during the phase of rapid degradation. These findings support a degradation pathway involving initial hydrolysis of amide to release fatty acids and methyl taurine, and subsequent degradation of these intermediates.

Biodegradation pathway of an anionic surfactant (Igepon TC-42) during recycling waste water through plant hydroponics for advanced life support during long-duration space missions

Science.gov (United States)

Levine, L. H.; Kagie, H. R.; Garland, J. L.

2003-01-01

The degradation of an anionic surfactant (Igepon TC-42) was investigated as part of an integrated study of direct recycling of human hygiene water through hydroponic plant growth systems. Several chemical approaches were developed to characterize the degradation of Igepon and to measure the accumulation of intermediates such as fatty acids and methyl taurine. Igepon was rapidly degraded as indicated by the reduction of methylene blue active substances (MBAS) and component fatty acids. The Igepon degradation rate continued to increase over a period of several weeks following repeated daily exposure to 18 micrograms/l Igepon. The accumulation of free fatty acids and methyl taurine was also observed during decomposition of Igepon. The concentration of methyl taurine was below detection limit (0.2 nmol/ml) during the slow phase of Igepon degradation, and increased to 1-2 nmol/ml during the phase of rapid degradation. These findings support a degradation pathway involving initial hydrolysis of amide to release fatty acids and methyl taurine, and subsequent degradation of these intermediates. Published by Elsevier Science Ltd on behalf of COSPAR.

Señales purinérgicas Purinergic signals

Directory of Open Access Journals (Sweden)

Eduardo R Lazarowski

2009-04-01

Full Text Available En la última década se ha aportado clara evidencia de que tanto nucleósidos como nucleótidos de adenina y uridina pueden funcionar como factores de señalización extracelular. Su acción es mediada por dos tipos principales de receptores de superficie denominados purinérgicos. Los receptores P1 se activan por adenosina, y son todos metabotrópicos, mientras que los receptores de nucleótidos (ATP, ADP, UTP y UDP y nucleótidos-azúcares (UDP-glucosa y UDP-galactosa pueden ser metabotrópicos (P2Y o ionotrópicos (P2X. La importancia y complejidad de este sistema de señalización se evidencia por la diversidad de mecanismos de liberación de nucleótidos al medio extracelular y por la distribución ubicua de varios grupos de ectonucleotidasas capaces de catalizar la degradación y conversión de nucleótidos. Hasta el momento se han descrito y clonado una veintena de estos receptores que modulan una variedad de respuestas, como el impulso nervioso, la respuesta inflamatoria, la secreción de insulina, la regulación del tono vascular y la percepción del dolor. En la presente revisión se describen las características estructurales y farmacológicas de los receptores purinérgicos y se analiza la interacción dinámica entre estos receptores, los nucleósidos y nucleótidos, y las ectonucleotidasas, con especial atención a la dinámica de la agregación plaquetaria, la respuesta inmune y la hidratación de las mucosas respiratorias.In the last decade evidence accumulated that nucleosides and nucleotides of both uridine and adenine can act as extracellular signaling factors. Their action is mediated by two main types of surface receptors commonly known as purinergic. P1 receptors are metabotropic and activated by adenosine, whereas receptors for nucleotides (ATP, ADP, UTP and UDP and nucleotide-sugars (UDP-glucose and UDP-galactose can be either metabotropic (P2Y or ionotropic (P2X. The importance and complexity of this signaling system

Recycling of plastic materials collected by `Duales System Deutschland (DSD)`; Werkstoffliches Recycling von Kunststoffen aus DSD-Sammlungen

Energy Technology Data Exchange (ETDEWEB)

Baumgaertner, D. [Lech-Elektrizitaetswerke AG, Augsburg (Germany); Heinz, H. [Lech-Elektrizitaetswerke AG, Augsburg (Germany); Hiller, W. [Lech-Elektrizitaetswerke AG, Augsburg (Germany)

1996-01-01

The article deals with the importance, problems and technology of plastics recycling. It gives an overview of the specific demands of plastics recyclates, the necessary process technology, and the characteristic values of materials. (orig.) [Deutsch] Es wird die Bedeutung, die Problematik und Technik des werkstofflichen Recyclings von Kunststoffen dargestellt. Dabei sind sowohl die spezifischen Anforderungen des Einsatzstoffes als Recyclingmaterial, die notwendige Verfahrenstechnik als auch die werkstofflichen Kennwerte in einer Uebersicht dargestellt. (orig.)

Multi-Fluid Modeling of Low-Recycling Divertor Regimes

International Nuclear Information System (INIS)

Smirnov, R.D.; Pigarov, A.Y.; Krasheninnikov, S.I.; Rognlien, T.D.; Soukhanovskii, V.A.; Rensink, M.E.; Maingi, R.; Skinner, C.H.; Stotler, D.P.; Bell, R.E.; Kugel, H.W.

2010-01-01

The low-recycling regimes of divertor operation in a single-null NSTX magnetic configuration are studied using computer simulations with the edge plasma transport code UEDGE. The edge plasma transport properties pertinent to the low-recycling regimes are demonstrated. These include the flux-limited character of the parallel heat transport and the high plasma temperatures with the flattened profiles in the scrape-off-layer. It is shown that to maintain the balance of particle fluxes at the core interface the deuterium gas puffing rate should increase as the divertor recycling coefficient decreases. The radial profiles of the heat load to the outer divertor plate, the upstream radial plasma profiles, and the effects of the cross-field plasma transport in the low-recycling regimes are discussed. It is also shown that recycling of lithium impurities evaporating from the divertor plate at high surface temperatures can reverse the low-recycling divertor operational regime to the high-recycling one and may cause thermal instability of the divertor plate.

Secondary resources and recycling in developing economies

International Nuclear Information System (INIS)

Raghupathy, Lakshmi; Chaturvedi, Ashish

2013-01-01

Recycling of metals extends the efficient use of minerals and metals, reduces pressure on environment and results in major energy savings in comparison to primary production. In developing economies recycling had been an integral part of industrial activity and has become a major concern due to the handling of potentially hazardous material without any regard to the occupational health and safety (OH and S) needs. With rising awareness and interest from policy makers, the recycling scenario is changing and the large scale enterprises are entering the recycling sector. There is widespread expectation that these enterprises would use the Best Available Technologies (BAT) leading to better environment management and enhanced resource recovery. The major challenge is to enhance and integrate the activities of other stakeholders in the value chain to make recycling an economically viable and profitable enterprise. This paper is an attempt to propose a sustainable model for recycling in the developing economies through integration of the informal and formal sectors. The main objective is to augment the existing practices using a scientific approach and providing better technology without causing an economic imbalance to the present practices. In this paper studies on lead acid batteries and e-waste recycling in India are presented to evolve a model for “green economy”

School Recycling Programs: A Handbook for Educators.

Science.gov (United States)

Environmental Protection Agency, Washington, DC.

This brochure describes some of the many recycling program options that schools can implement in their communities. It focuses on implementing actual recycling projects as a way of teaching the importance and benefits of recycling. The text examines the solid waste crisis and why Americans cannot continue to possess a disposable mentality. It…

Requirements for the recycling of hazardous waste

International Nuclear Information System (INIS)

Petts, M.

1990-09-01

The regulatory status of materials destined to be recycled is not always clear. There have been numerous questions from DOE Field Elements regarding the applicability of the Resource Conservation and Recovery Act (RCRA) to certain materials that can be recycled. The Office of Environmental Guidance, RCRA/CERCLA Division, has responded to questions relating to the RCRA regulations as they apply to materials that are recycled or are destined for recycling. Additional regulatory requirements for these materials may be promulgated upon the reauthorization of RCRA (e.g., regulation of used oil). Additional EH-23 information Briefs will be issued as these regulations develop. The Office of Environment, Safety and Health has convened a workshop to establish DOE's position on a number of issues associated with mixed waste and materials management, several relative to recycling

National plan for the radioactive and recyclable wastes management of the national inventory of the radioactive and recyclable wastes to an account and a prospective outlook of the pathways of long dated management of radioactive wastes in France; Plan national de gestion des dechets radioactifs et des matieres valorisables de l'inventaire national des dechets radioactifs et des matieres valorisable a un bilan et une vision prospective des filieres de gestion a long terme des dechets radioactifs en France

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-15

The introduction recalls the context of the development of the national plan of radioactive and recyclable wastes management (PNGDR-MV), its objectives and its position in the today studies on radioactive wastes. The first part is devoted to the description of existing radioactive wastes management solutions, or engaged by today activities. The second part concerns the radioactive materials of the nuclear industry, which are not considered as wastes, but which can be recyclable because of their high energy potential as fuels for reactors of the future. The third part examines the pathways coherence. The last part is a synthesis of the evaluation, with more attention on the identifies problems. (A.L.B.)

Software recycling at the Hanford Site

International Nuclear Information System (INIS)

HINKELMAN, K.C.

1999-01-01

The Hanford Site was the first Department of Energy (DOE) complex to recycle excess software rather than dispose of it in the landfill. This plan, which took over a year to complete, was reviewed for potential legal conflicts, which could arise from recycling rather than disposal of software. It was determined that recycling was an approved method of destruction and therefore did not conflict with any of the licensing agreements that Hanford had with the software manufacturers. The Hanford Recycling Program Coordinator combined efforts with Pacific Northwest National Laboratory (PNNL) to recycle all Hanford software through a single contract, which went out for bid in January 1995. It was awarded to GreenDisk, Inc. located in Woodinville Washington and implemented in March 1995. The contract was later re-bid and awarded to EcoDisWGreenDisk in December 1998. The new contract included materials such as; software manuals, diskettes, tyvek wrapping, cardboard and paperboard packaging, compact disks (CDs), videotapes, reel-to-reel tapes, magnetic tapes, audio tapes, and many other types of media

Pathway-specific differences between tumor cell lines and normal and tumor tissue cells

Directory of Open Access Journals (Sweden)

Tozeren Aydin

2006-11-01

Full Text Available Abstract Background Cell lines are used in experimental investigation of cancer but their capacity to represent tumor cells has yet to be quantified. The aim of the study was to identify significant alterations in pathway usage in cell lines in comparison with normal and tumor tissue. Methods This study utilized a pathway-specific enrichment analysis of publicly accessible microarray data and quantified the gene expression differences between cell lines, tumor, and normal tissue cells for six different tissue types. KEGG pathways that are significantly different between cell lines and tumors, cell lines and normal tissues and tumor and normal tissue were identified through enrichment tests on gene lists obtained using Significance Analysis of Microarrays (SAM. Results Cellular pathways that were significantly upregulated in cell lines compared to tumor cells and normal cells of the same tissue type included ATP synthesis, cell communication, cell cycle, oxidative phosphorylation, purine, pyrimidine and pyruvate metabolism, and proteasome. Results on metabolic pathways suggested an increase in the velocity nucleotide metabolism and RNA production. Pathways that were downregulated in cell lines compared to tumor and normal tissue included cell communication, cell adhesion molecules (CAMs, and ECM-receptor interaction. Only a fraction of the significantly altered genes in tumor-to-normal comparison had similar expressions in cancer cell lines and tumor cells. These genes were tissue-specific and were distributed sparsely among multiple pathways. Conclusion Significantly altered genes in tumors compared to normal tissue were largely tissue specific. Among these genes downregulation was a major trend. In contrast, cell lines contained large sets of significantly upregulated genes that were common to multiple tissue types. Pathway upregulation in cell lines was most pronounced over metabolic pathways including cell nucleotide metabolism and oxidative

Model institutional infrastructures for recycling of photovoltaic modules

Energy Technology Data Exchange (ETDEWEB)

Reaven, S.J.; Moskowitz, P.D.; Fthenakis, V.

1996-01-01

How will photovoltaic modules (PVMS) be recycled at the end of their service lives? This question has technological and institutional components (Reaven, 1994a). The technological aspect concerns the physical means of recycling: what advantages and disadvantages of the several existing and emerging mechanical, thermal, and chemical recycling processes and facilities merit consideration? The institutional dimension refers to the arrangements for recycling: what are the operational and financial roles of the parties with an interest in PVM recycling? These parties include PVM manufacturers, trade organizations; distributors, and retailers; residential, commercial, and utility PVM users; waste collectors, transporters, reclaimers, and reclaimers; and governments.

Platinum recycling in the United States in 1998

Science.gov (United States)

Hilliard, Henry E.

2001-01-01

In the United States, catalytic converters are the major source of secondary platinum for recycling. Other sources of platinum scrap include reforming and chemical process catalysts. The glass industry is a small but significant source of platinum scrap. In North America, it has been estimated that in 1998 more than 20,000 kilograms per year of platinum-group metals from automobile catalysts were available for recycling. In 1998, an estimated 7,690 kilograms of platinum were recycled in the United States. U.S. recycling efficiency was calculated to have been 76 percent in 1998; the recycling rate was estimated at 16 percent.

Radioactive materials in recycled metals.

Science.gov (United States)

Lubenau, J O; Yusko, J G

1995-04-01

In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

Going for increased recycling. A social cost-benefit analysis; Inzetten op meer recycling. Een maatschappelijke kosten-batenanalyse

Energy Technology Data Exchange (ETDEWEB)

Warringa, G.E.A.; De Bruyn, M.; Bijleveld, M.M.

2013-05-15

While the environmental benefits of scenarios geared to increased recycling have been convincingly demonstrated by previous studies, the question arises whether such scenarios bring economic benefits, too. This study therefore assesses the main economic effects of increased recycling in the Netherlands, providing data that can be used to advance policy development in this area. To address the main issue we performed a social cost-benefit analysis (SCBA), a welfare-theory-based tool that can be used to chart the full range of economic impacts ('welfare impacts') of a project or policy intervention. In doing so, a broad definition of welfare is adopted, encompassing not only financial and economic consequences, but also environmental and employment impacts and so on. Using SimaPro, all the environmental interventions inventoried (including energy consumption, transport and recycling process emissions) were assessed for each individual material flow, with impacts being expressed as far as possible in monetary terms to enable comparison. The main social costs of increased recycling are the higher costs for local authorities associated with separate waste collection. There is also reduced revenue for waste incinerators, because more waste will need to be imported from abroad. Finally, there are the policy costs of incentives for increased recycling and extra efforts to induce citizens to separate their waste. The latter costs were not quantified. Over and against these costs are positive welfare impacts. The main benefits are environmental, expressed monetarily in the present study in terms of avoided damage costs for society as a whole and avoided measures for securing government reduction targets. In addition, the separated waste has a value, reflected in lower processing costs. Increased recycling also creates new jobs, while recycling firms generate more profit than waste incinerators. Finally, there are the benefits accruing from greater innovation and

Modification of Purine and Pyrimidine Nucleosides by Direct C-H Bond Activation

Directory of Open Access Journals (Sweden)

Yong Liang

2015-03-01

Full Text Available Transition metal-catalyzed modifications of the activated heterocyclic bases of nucleosides as well as DNA or RNA fragments employing traditional cross-coupling methods have been well-established in nucleic acid chemistry. This review covers advances in the area of cross-coupling reactions in which nucleosides are functionalized via direct activation of the C8-H bond in purine and the C5-H or C6-H bond in uracil bases. The review focuses on Pd/Cu-catalyzed couplings between unactivated nucleoside bases with aryl halides. It also discusses cross-dehydrogenative arylations and alkenylations as well as other reactions used for modification of nucleoside bases that avoid the use of organometallic precursors and involve direct C-H bond activation in at least one substrate. The scope and efficiency of these coupling reactions along with some mechanistic considerations are discussed.

Reprocessing-recycling, or the application of the selective sorting and recycling policy to nuclear activities

International Nuclear Information System (INIS)

1998-12-01

In France, the reprocessing of spent fuels is the solution that has been retained for the management of the end-of-cycle. The sorting of the different components of spent fuels allows the recycling of uranium and plutonium for the further production of enriched uranium and mixed oxide fuels. This paper presents Cogema's advances in this domain (facilities and plants), the transfer of Cogema's reprocessing and recycling technologies in other countries (Japan, USA, Russia), the economical and environmental advantages of the recycling of spent fuels, the economical resources provided by this activity, and the cooperation with foreign countries for the reprocessing of their spent fuels at Cogema-La Hague. (J.S.)

Integration of Demilitarization Contractors and Recyclers - Collateral Benefits of On-Site Training of Recyclers

Science.gov (United States)

2010-07-01

item Spherical? Wedge Shaped? Cylindrical? These items are potentially very dangerous 29 Spherical = Not Good If found in a recycling yard, don’t...touch! Call 9-1-1 BLU-63 30 Wedge Shape = Not Good If found in a recycling yard, don’t touch! Call 9-1-1 M72M43 31 Cylindrical = Not Good If found in a

Measures for recycling plastic wastes in France

Energy Technology Data Exchange (ETDEWEB)

Cossais, J C [Ministere de l' Industrie et de la Recherche, 75 - Paris (France). Delegation aux Economies de Matieres Premieres

1978-05-01

Raw materials crisis and environmental awareness have lead to the question of intensively dealing with the recycling of plastics. Although plastic wastes (residues) industrially occuring have been recycled for a long time, this is certainly not always the case in the subsequent stages. One must particularly give thought to the considerable quantities of agricultural and municipal wastes. Besides the problem of collecting the waste which can only be satisfactorily solved by separate collection or setting up sorting places, it is necessary for the recycling plastic wastes on a large scale to find or develop sellable products. The product for sale is limited by economical aspects and prejudices against recycled materials. The public have taken to a series of measures in France to simplify recycling plastic wastes. Private industry is also beginning to take interest in this new sources of raw materials.

Durable Recycled Superpave Mixes in Kansas

Science.gov (United States)

2018-04-01

The use of economical and environment-friendly recycled asphalt materials has become increasingly popular for asphalt pavement construction. In general, reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) are used in hot-mix asphalt ...

Proteomic analysis of the signaling pathway mediated by the heterotrimeric Gα protein Pga1 of Penicillium chrysogenum.

Science.gov (United States)

Carrasco-Navarro, Ulises; Vera-Estrella, Rosario; Barkla, Bronwyn J; Zúñiga-León, Eduardo; Reyes-Vivas, Horacio; Fernández, Francisco J; Fierro, Francisco

2016-10-06

The heterotrimeric Gα protein Pga1-mediated signaling pathway regulates the entire developmental program in Penicillium chrysogenum, from spore germination to the formation of conidia. In addition it participates in the regulation of penicillin biosynthesis. We aimed to advance the understanding of this key signaling pathway using a proteomics approach, a powerful tool to identify effectors participating in signal transduction pathways. Penicillium chrysogenum mutants with different levels of activity of the Pga1-mediated signaling pathway were used to perform comparative proteomic analyses by 2D-DIGE and LC-MS/MS. Thirty proteins were identified which showed differences in abundance dependent on Pga1 activity level. By modifying the intracellular levels of cAMP we could establish cAMP-dependent and cAMP-independent pathways in Pga1-mediated signaling. Pga1 was shown to regulate abundance of enzymes in primary metabolic pathways involved in ATP, NADPH and cysteine biosynthesis, compounds that are needed for high levels of penicillin production. An in vivo phosphorylated protein containing a pleckstrin homology domain was identified; this protein is a candidate for signal transduction activity. Proteins with possible roles in purine metabolism, protein folding, stress response and morphogenesis were also identified whose abundance was regulated by Pga1 signaling. Thirty proteins whose abundance was regulated by the Pga1-mediated signaling pathway were identified. These proteins are involved in primary metabolism, stress response, development and signal transduction. A model describing the pathways through which Pga1 signaling regulates different cellular processes is proposed.

Secondary resources and recycling in developing economies.

Science.gov (United States)

Raghupathy, Lakshmi; Chaturvedi, Ashish

2013-09-01

Recycling of metals extends the efficient use of minerals and metals, reduces pressure on environment and results in major energy savings in comparison to primary production. In developing economies recycling had been an integral part of industrial activity and has become a major concern due to the handling of potentially hazardous material without any regard to the occupational health and safety (OH&S) needs. With rising awareness and interest from policy makers, the recycling scenario is changing and the large scale enterprises are entering the recycling sector. There is widespread expectation that these enterprises would use the Best Available Technologies (BAT) leading to better environment management and enhanced resource recovery. The major challenge is to enhance and integrate the activities of other stakeholders in the value chain to make recycling an economically viable and profitable enterprise. This paper is an attempt to propose a sustainable model for recycling in the developing economies through integration of the informal and formal sectors. The main objective is to augment the existing practices using a scientific approach and providing better technology without causing an economic imbalance to the present practices. In this paper studies on lead acid batteries and e-waste recycling in India are presented to evolve a model for "green economy". Copyright © 2013 Elsevier B.V. All rights reserved.

Sustainability and training materials for in-place recycling.

Science.gov (United States)

2016-04-22

Hot and cold in-place recycling techniques recycle 100 percent of a hot mix asphalt (HMA) pavement, in place, during the maintenance/rehabilitation process. Numerous studies have shown in-place recycling to be a sustainable, cost-effective procedure ...

The Dynamic Earth: Recycling Naturally!

Science.gov (United States)

Goldston, M. Jenice; Allison, Elizabeth; Fowler, Lisa; Glaze, Amanda

2013-01-01

This article begins with a thought-provoking question: What do you think of when you hear the term "recycle?" Many think about paper, glass, aluminum cans, landfills, and reducing waste by reusing some of these materials. How many of us ever consider the way the systems of Earth dynamically recycle its materials? In the following…

Multi-fluid modeling of low-recycling divertor regimes

International Nuclear Information System (INIS)

Smirnov, R.D.; Pigarov, A.Yu.; Krasheninnikov, S.I.; Rognlien, T.D.; Soukhanovskii, V.A.; Rensink, M.E.; Maingi, R.; Skinner, C.H.; Stotler, D.P.; Bell, R.E.; Kugel, H.W.

2010-01-01

The low-recycling regimes of divertor operation in a single-null NSTX magnetic configuration are studied using computer simulations with the edge plasma transport code UEDGE. The edge plasma transport properties pertinent to the low-recycling regimes are demonstrated. These include the flux-limited character of the parallel heat transport and the high plasma temperatures with the flattened profiles in the scrape-off-layer. It is shown that to maintain the balance of particle fluxes at the core interface the deuterium gas puffing rate should increase as the divertor recycling coefficient decreases. The radial profiles of the heat load to the outer divertor plate, the upstream radial plasma profiles, and the effects of the cross-field plasma transport in the low-recycling regimes are discussed. It is also shown that recycling of lithium impurities evaporating from the divertor plate at high surface temperatures can reverse the low-recycling divertor operational regime to the high-recycling one and may cause thermal instability of the divertor plate (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Effects of chicory inulin on serum metabolites of uric acid, lipids, glucose, and abdominal fat deposition in quails induced by purine-rich diets.

Science.gov (United States)

Lin, Zhijian; Zhang, Bing; Liu, Xiaoqing; Jin, Rui; Zhu, Wenjing

2014-11-01

Inulin, a group of dietary fibers, is reported to improve the metabolic disorders. In the present study, we investigated the effects of chicory inulin on serum metabolites of uric acid (UA), lipids, glucose, and abdominal fat deposition in quail model induced by a purine-rich diet. In this study, 60 male French quails were randomly allocated to five groups: CON (control group), MOD (model group), BEN (benzbromarone-treated group), CHI-H (high-dosage chicory inulin-treated group), and CHI-L (low-dosage chicory inulin-treated group). The serum UA level was significantly increased in the model group from days 7 to 28, as well as triglyceride (TG) and free fatty acid (FFA) increased later in the experimental period. The abdominal fat ratio was increased on day 28. Benzbromarone can decrease UA levels on days 14 and 28. The high and low dosage of chicory inulin also decreased serum UA levels on days 7, 14, and 28. The abdominal fat ratio, activity, and protein of acetyl-CoA carboxylase (ACC) were decreased in chicory inulin-treated groups. The activities of xanthine oxidase (XOD) and fatty acid synthase (FAS) were increased in the model group and decreased in the benzbromarone and chicory inulin groups. This study evaluated a quail model of induced hyperuricemia with other metabolic disorders caused by a high-purine diet. The results indicated that a purine-rich diet might contribute to the development of hyperuricemia, hypertriglyceridemia, and abdominal obesity. Chicory inulin decreased serum UA, TG, and abdominal fat deposition in a quail model of hyperuricemia by altering the ACC protein expression and FAS and XOD activities.

Methods of Recycling, Properties and Applications of Recycled Thermoplastic Polymers

Directory of Open Access Journals (Sweden)

Mădălina Elena Grigore

2017-11-01

Full Text Available This study aims to provide an updated survey of the main thermoplastic polymers in order to obtain recyclable materials for various industrial and indoor applications. The synthesis approach significantly impacts the properties of such materials and these properties in turn have a significant impact on their applications. Due to the ideal properties of the thermoplastic polymers such as corrosion resistance, low density or user-friendly design, the production of plastics has increased markedly over the last 60 years, becoming more used than aluminum or other metals. Also, recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today.

The chemical recycle of cotton

Directory of Open Access Journals (Sweden)

Alice Beyer Schuch

2016-08-01

Full Text Available The chemical recycle of cotton textiles and/or other cellulosic materials for the purpose of manufacturing regenerated high quality textiles fibres is a novel process. The objective of related research is based on the forecast of population growth, on resource scarcity predictions, and on the negative environmental impact of the textile industry. These facts lead the need of broadening the scope for long-term textile-to-textile recycle - as the mechanical recycle of natural fibres serve for limited number of cycles, still depends on input of virgin material, and offer a reduced-in-quality output. Critical analysis of scientific papers, relevant related reports, and personal interviews were the base of this study, which shows viable results in laboratorial scale of using low-quality cellulosic materials as input for the development of high-quality regenerated textile fibres though ecological chemical process. Nevertheless, to scale up and implement this innovative recycle method, other peripheral structures are requested, such as recover schemes or appropriate sort, for instance. Further researches should also be considered in regards to colours and impurities.

Recycled materials in Portland cement concrete

Science.gov (United States)

2000-06-01

This report pertains to a comprehensive study involving the use of recycled materials in Portland cement concrete. Three different materials were studied including crushed glass (CG), street sweepings (SS), and recycled concrete (RC). Blast furnace s...

Case studies in rural recycling. Public service report series

Energy Technology Data Exchange (ETDEWEB)

Cosper, S.D.; Hallenbeck, W.H.; Brenniman, G.R.

1994-02-01

Due to state planning requirements and federal landfill regulations, solid waste management in rural areas (particularly recycling) has received much attention in recent years. The growth of recycling during the 1980s occurred mainly in urban and suburban areas. Therefore, rural recycling is still a relatively new enterprise. This report presents several rural recycling case studies from Colorado, Illinois, Indiana, Iowa, Minnesota, Tennessee, and Ontario, Canada to provide examples of successes and problems. This report also discusses the current issues of cooperative marketing of recyclables and municipal solid waste flow control. With respect to recycling, a rural region does not have ready access to markets for collected materials and has difficulty in generating easily marketable quantities of recyclables. (Copyright (c) 1994 The Board of Trustees of the University of Illinois.)

Development of a neutral network model to predict the excretion of purine derivatives in the urine of cows

International Nuclear Information System (INIS)

Volpe, V.; Stefanon, B.; Moscardini, S.; Susmel, P.; Gruber, L.

1999-01-01

A Neural Network Model to predict the urinary excretion of purine derivative nitrogen (UPDN) in cows is presented. The input variables of the model are dry matter intake (DMINT), NDF intake (NDFINT), total soluble nitrogen (SP), total soluble non-protein dry matter (SNPDM), total degradable nitrogen (DCP), total degradable non-protein dry matter (DNPDM), hourly available CP in the rumen (HACP), hourly available non-protein dry matter (HANPDM), three different gross indexes of synchronization, namely SYNCA (SP/SNPDM), SYNCB (DCP/DNPDM) and SYNCK (HACP/HANPDM) and two variables describing some metabolic aspects of purine derivative excretion such as live weight of the cow (LW) and milk yield (MILKY). The Model developed uses the Multi Layer Perceptron (MLP) utility, with 13 nodes in the input layer, 8 nodes in the hidden layer and 1 node in the output layer. The Model performances have been tested over 24 observations not previously used to train the model. When compared to a linear regression approach, the Neural Network model showed better performance but under predicted the daily excretion of UPDN for values around 20 g/day. When evaluated in terms of behaviour and depicted scenario the model responded to changes of live weight (LW) and milk yield (MILKY) and to modifications of the pattern of nutrients supplied to rumen microbes. (author)

Development of a neutral network model to predict the excretion of purine derivatives in the urine of cows

Energy Technology Data Exchange (ETDEWEB)

Volpe, V; Stefanon, B; Moscardini, S; Susmel, P [University of Udine, Department of Animal Production Science, Pagnacco, UD (Italy); Gruber, L [Federal Research Institute for Agriculture in the Alpine Regions, Irdning (Austria)

1999-06-01

A Neural Network Model to predict the urinary excretion of purine derivative nitrogen (UPDN) in cows is presented. The input variables of the model are dry matter intake (DMINT), NDF intake (NDFINT), total soluble nitrogen (SP), total soluble non-protein dry matter (SNPDM), total degradable nitrogen (DCP), total degradable non-protein dry matter (DNPDM), hourly available CP in the rumen (HACP), hourly available non-protein dry matter (HANPDM), three different gross indexes of synchronization, namely SYNCA (SP/SNPDM), SYNCB (DCP/DNPDM) and SYNCK (HACP/HANPDM) and two variables describing some metabolic aspects of purine derivative excretion such as live weight of the cow (LW) and milk yield (MILKY). The Model developed uses the Multi Layer Perceptron (MLP) utility, with 13 nodes in the input layer, 8 nodes in the hidden layer and 1 node in the output layer. The Model performances have been tested over 24 observations not previously used to train the model. When compared to a linear regression approach, the Neural Network model showed better performance but under predicted the daily excretion of UPDN for values around 20 g/day. When evaluated in terms of behaviour and depicted scenario the model responded to changes of live weight (LW) and milk yield (MILKY) and to modifications of the pattern of nutrients supplied to rumen microbes. (author) 16 refs, 11 figs, 1 tab

Low to high performance recycled cementitious materials: case studies

OpenAIRE

Etxeberria Larrañaga, Miren

2015-01-01

In this work, four real case studies using concrete produced with recycled aggregates are described. The four real cases carried out in Barcelona are: 1) Pavement filling with control low strength material (CLSM) employing fine recycled aggregates, 2) pervious recycled aggregate concrete employing coarse mixed recycled aggregates in the works undertaken at Cervantes park; 3) Concrete blocks produced employing recycled and slag aggregates as well as sea water for a new breakwater dyke and 4) R...

Synthesis 1-(5-oxohexyl)-3,7-dimethyl-xanthyne labelled with tritium into 8 position from purinic ring

International Nuclear Information System (INIS)

Mihaila, V.; Corol, D.

1999-01-01

This paper presents the work on synthesis of 1-(5-oxohexyl)-3,7-dimethyl-xanthyne labelled with tritium into 8 position from purinic ring. The obtaining of tritium labelled compound is realized by initial labelling of theobromine with tritium into 8 position and by coupling the purinic derivative to 1-Br-5-hexanone. Theobromine-8- 3 H was obtained by the bromination of theobromine with elementary bromine and after that the bromine was substituted with tritium i.e.: C 7 H 8 O 2 N 4 theobromine Br 2 /(-HBr) C 7 H 7 O 2 N 4 Br (8-Br-theobromine) ( 3 H 2 /cat)/(-KOH) C 7 H 7 3 HO 2 N 4 (theobromine-8- 3 H). Theobromine-8- 3 H was purified by thin layer chromatography with a solvent system i.e. n-BuOH:AcOH:H 2 O (4:1:1, v/v/v) and characterized radiochemically. It was then diluted by unlabelled theobromine to specific activity of 50 mCi/g. After dilution, theobromine-8- 3 H was coupled to 1-Br-5-hexanone i.e.: C 7 H 7 3 HO 2 N 4 (theobromine-8- 3 H) + Br-(CH 2 ) 4 -CO-CH 3 (1-Br-5-hexanone) (NaOH)/(CH 3 OH) C 13 H 17 3 HO 3 N 4 (1-(5-oxohexyl)- 3,7-dimethyl-xanthine-8- 3 H). The raw compound was purified by recrystallization from 2-propanol and it was characterized radiochemically. (authors)

Pre-Saturation Technique of the Recycled Aggregates: Solution to the Water Absorption Drawback in the Recycled Concrete Manufacture.

Science.gov (United States)

García-González, Julia; Rodríguez-Robles, Desirée; Juan-Valdés, Andrés; Morán-Del Pozo, Julia Mª; Guerra-Romero, M Ignacio

2014-09-01

The replacement of natural aggregates by recycled aggregates in the concrete manufacturing has been spreading worldwide as a recycling method to counteract the large amount of construction and demolition waste. Although legislation in this field is still not well developed, many investigations demonstrate the possibilities of success of this trend given that concrete with satisfactory mechanical and durability properties could be achieved. However, recycled aggregates present a low quality compared to natural aggregates, the water absorption being their main drawback. When used untreated in concrete mix, the recycled aggregate absorb part of the water initially calculated for the cement hydration, which will adversely affect some characteristics of the recycled concrete. This article seeks to demonstrate that the technique of pre-saturation is able to solve the aforementioned problem. In order to do so, the water absorption of the aggregates was tested to determine the necessary period of soaking to bring the recycled aggregates into a state of suitable humidity for their incorporation into the mixture. Moreover, several concrete mixes were made with different replacement percentages of natural aggregate and various periods of pre-saturation. The consistency and compressive strength of the concrete mixes were tested to verify the feasibility of the proposed technique.

Energy implications of recycling packaging materials

Energy Technology Data Exchange (ETDEWEB)

Gaines, L.L. [Argonne National Lab., IL (United States); Stodolsky, F. [Argonne National Lab., Washington, DC (United States)

1994-03-01

In 1992, Congress sought to rewrite the United States comprehensive solid waste legislation -- the Resource Conservation and Recovery Act (RCRA). Commodity-specific recycling rates were proposed for consumer-goods packaging materials and newsprint We compare the impacts on energy, materials use, and landfill volume of recycling at those rates to the impacts for alternative methods of material disposition to determine the optimum for each material. After products have served their intended uses, there are several alternative paths for material disposition. These include reuse, recycling to the same product, recycling to a lower-valued product, combustion for energy recovery, incineration without energy recovery, and landfill. Only options considered to be environmentally sound are Included. Both houses of Congress specifically excluded combustion for energy recovery from counting towards the recovery goats, probably because combustion is viewed as a form of disposal and is therefore assumed to waste resources and have n environmental effects. However, co-combustion in coal-fired plants or combustion in appropriately pollution-controlled waste-to-energy plants Is safe, avoids landfill costs, and can displace fossil fuels. In some cases, more fossil fuels can be displaced by combustion than by recycling. We compare the alternative life-cycle energies to the energies for producing the products from virgin materials. Results depend on the material and on the objective to be achieved. There are trade-offs among possible goals. For instance, paper packaging recycling conserves trees but may require greater fossil-fuel input than virgin production. Therefore, the objectives for proposed legislation must be examined to see whether they can most effectively be achieved by mandated recycling rates or by other methods of disposition. The optimal choices for the United States may not necessarily be the same as those for Europe and other parts of the world.

Cyclotrimerization of 6-ethynylpurines. Synthesis of 1,2,4- and 1,3,5-tris(purin-6-yl)benzenes as novel Hoogsteen-triplet analogues

Czech Academy of Sciences Publication Activity Database

Hocek, Michal; Stará, Irena G.; Starý, Ivo; Dvořáková, H.

2001-01-01

Roč. 42, č. 3 (2001), s. 519-521 ISSN 0040-4039 R&D Projects: GA ČR GA203/00/0036; GA ČR GA203/99/1448 Institutional research plan: CEZ:AV0Z4055905 Keywords : purines * cyclotrimerizations Subject RIV: CC - Organic Chemistry Impact factor: 2.280, year: 2001

Recycling of plastics in Germany

International Nuclear Information System (INIS)

Thienen, N. von; Patel, M.

1999-01-01

This article deals with the waste management of post-consumer plastics in Germany and its potential to save fossil fuels and reduce CO 2 emissions. Since most experience is available for packaging, the paper first gives an overview of the legislative background and the material flows for this sector. Then recycling and recovery processes for plastics waste from all sectors are assessed in terms of their contribution to energy saving and CO 2 abatement. Practically all the options studied show a better performance than waste treatment in an average incinerator which has been chosen as the reference case. High ecological benefits can be achieved by mechanical recycling if virgin polymers are substituted. The paper then presents different scenarios for managing plastic waste in Germany in 1995: considerable savings can be made by strongly enhancing the efficiency of waste incinerators. Under these conditions the distribution of plastics waste among mechanical recycling, feedstock recycling and energy recovery has a comparatively mall impact on the overall results. The maximum savings amount to 74 PJ of energy, i.e, 9% of the chemical sector energy demand in 1995 and 7.0 Mt CO 2 , representing 13% of the sector's emissions. The assessment does not support a general recommendation of energy recovery due to the large difference between the German average and the best available municipal waste-to-energy facilities and also due to new technological developments in the field of mechanical recycling

Effect of Recycling in Post-Consumer Polystyrene Cups

OpenAIRE

Ahmed, Mehnaz

2016-01-01

The aim of the thesis was to recycle post-consumer polystyrene cups and to analyze the changes in mechanical and rheological properties of the recycled polystyrene. The me-chanical properties were tensile strength, Young’s modulus and the rheological proper-ties was melt flow index. In order to analyze the changes in properties, material testing results of pristine polystyrene were compared with the recycled polystyrene. The same polystyrene material was recycled and tested twice in order to ...

Planning of Eka Hospital Pekanbaru wastewater recycling facility

Science.gov (United States)

Jecky, A.; Andrio, D.; Sasmita, A.

2018-04-01

The Ministry of Public Works No. 06 2011 required the large scale of water to conserve the water resource, Eka Hospital Pekanbaru have to improve the sewage treatment plant through the wastewater recycling. The effluent from the plant can be used to landscape gardening and non-potable activities. The wastewater recycling design was done by analyzing the existing condition of thesewage treatment plant, determine the effluent quality standards for wastewater recycling, selected of alternative technology and processing, design the treatment unit and analyze the economic aspects. The design of recycling facility by using of combination cartridge filters processing, ultrafiltration membranes, and desinfection by chlorination. The wastewater recycling capacity approximately of 75 m3/day or 75% of the STP effluent. The estimated costs for installation of wastewater recycling and operation and maintenance per month are Rp 111,708,000 and Rp 2,498,000 respectively.

Long-term aging of recycled binders.

Science.gov (United States)

2015-07-01

Asphalt pavement is Americas most recycled material. Eighty million tons of asphalt, nearly 80% of all milled asphalt pavement, : is recycled every year [1]. To effectively maintain its 40,000 miles of paved roads, the Florida Department of Transp...

Sustainability issues in circuit board recycling

DEFF Research Database (Denmark)

Legarth, Jens Brøbech; Alting, Leo; Baldo, Gian Luca

1995-01-01

The resource recovery and environmental impact issues of printed circuit board recycling by secondary copper smelters are discussed. Guidelines concerning material selection for circuit board manufacture and concerning the recycling processes are given to enhance recovery efficiency and to lower...

COMPOSITES FROM RECYCLED WOOD AND PLASTICS

Science.gov (United States)

The ultimate goal of this research was to develop technology to convert recycled wood fiber and plastics into durable products that are recyclable and otherwise environmentally friendly. Two processing technologies were used to prepare wood-plastic composites: air-laying and melt...

N9-Substituted N(6)-[(3-methylbut-2-en-1-yl)amino]purine derivatives and their biological activity in selected cytokinin bioassays

Czech Academy of Sciences Publication Activity Database

Mik, V.; Szüčová, Lucie; Spíchal, Lukáš; Plíhal, O.; Nisler, Jaroslav; Zahajská, L.; Doležal, Karel; Strnad, Miroslav

2011-01-01

Roč. 19, č. 23 (2011), s. 7244-7251 ISSN 0968-0896 R&D Projects: GA MŠk ED0007/01/01; GA ČR GA522/09/1576 Keywords : N6-[(3-Methylbut-2-en-1-yl)amino]purine * Isopentenyladenine derivatives * N9-Substituted derivatives * Cytokinins * Cytokinin receptors Subject RIV: EF - Botanics Impact factor: 2.921, year: 2011

Attitudes toward text recycling in academic writing across disciplines.

Science.gov (United States)

Hall, Susanne; Moskovitz, Cary; Pemberton, Michael A

2018-01-01

Text recycling, the reuse of material from one's own previously published writing in a new text without attribution, is a common academic writing practice that is not yet well understood. While some studies of text recycling in academic writing have been published, no previous study has focused on scholars' attitudes toward text recycling. This article presents results from a survey of over 300 journal editors and editorial board members from 86 top English-language journals in 16 different academic fields regarding text recycling in scholarly articles. Responses indicate that a large majority of academic gatekeepers believe text recycling is allowable in some circumstances; however, there is a lack of clear consensus about when text recycling is or is not appropriate. Opinions varied according to the source of the recycled material, its structural location and rhetorical purpose, and conditions of authorship conditions-as well as by the level of experience as a journal editor. Our study suggests the need for further research on text recycling utilizing focus groups and interviews.

Physics of plutonium recycling: volume V. Plutonium recycling in fast reactors

International Nuclear Information System (INIS)

1996-01-01

As part of a programme proposed by the OECD/NEA Working Party on Physics of Plutonium Recycling (WPPR) to evaluate different scenarios for the use of plutonium, fast reactor physics benchmarks were developed. In this report, the multi-recycle performance of the metal-fuelled benchmark is evaluated. Benchmark results assess the reactor performance and toxicity behaviour in a closed nuclear fuel cycle for a parametric variation of the conversion ratio between 0.5 and 1.0. Results indicate that a fast burner reactor closed fuel cycle can be utilised to significantly reduce the radiotoxicity originating in the LWR cycle which would otherwise be destined for burial. (Author). tabs., figs., refs

Socio-Spatial Factors Affecting Household Recycling in Townhouses in Pretoria, South Africa

Directory of Open Access Journals (Sweden)

Jacques du Toit

2017-11-01

Full Text Available Although social factors affecting recycling have been widely researched, the effect of spatial and physical factors posed by medium-density housing, such as townhouses, is less understood. Using the Theory of Planned Behaviour, the relative effect of three sets of factors on household recycling in townhouses are examined, including ‘attitude’ (about recycling, ‘subjective norm’ (social pressure, and ‘perceived behaviour control’ (ability to recycle. A questionnaire survey of 300 households was conducted in Equestria, an enclosed middle-income residential estate consisting of several townhouse complexes. Confirmatory factor analysis verified the three factor measurement model for recycling participation. Both recyclers and non-recyclers showed positive attitudes toward recycling and felt social pressure to recycle. Non-recyclers, however, felt significantly less able to recycle. Most recyclers as well as non-recyclers indicated that certain proposals for increasing recycling may cause them to recycle more, in particular a system through which the management agency arranges access for a recycling company to collect recyclables from strategically located collection points inside the complex. Urban planning and design recommendations for facilitating recycling in townhouses are discussed.

Recycling of beverage containers in the Northwest Territories

Energy Technology Data Exchange (ETDEWEB)

1987-02-01

This study researched existing recycling systems, presented pertinent data on the beverage and transportation industries, and evaluated the potential of recycling beverage bottles and cans in the Northwest Territories. The study first describes the history and existing concepts of recycling, provides a general description of recycling methods with advantages and disadvantages, and highlights particular approaches taken by other provinces. Markets for the Northwest Territories are also discussed, including the potential of recoverable material, anticipated recovery rates, transportation to markets, and present recycling operations. Three strategies are identified for the southwest, northwest, and the eastern Region. Recycling is preferred for aluminium cans, glass beer bottles, plastic bottles, and glass wine and liquor bottles in that order. The report recommends a limited program for aluminium cans and beer bottles to begin immediately. Beer bottles should be refilled either in Alberta or the Northwestern Territories and aluminium cans should be compacted and shipped to recycling markets in southern Canada or the United States. The program should first be implemented in areas serviced by Alberta and accessible by truck or barge from Hay River. A program implementation plan is also included. 8 refs., 2 figs., 14 tabs.

Comparative analysis of old, recycled and new PV modules

Directory of Open Access Journals (Sweden)

Haroon Ashfaq

2017-01-01

Full Text Available This paper presents comparative analysis of old, recycled and new PV modules. It is possible to recycle even very old products by modern standard processes in a value-conserving manner. About 90% of the materials recovered from solar panels can be recycled into useful products. Carbon emission and energy cost are low in manufacturing recycled SPV. Modules can be manufactured with recycled materials and reinstalled in systems as a full quality product with today’s technology good for another 25–30 years. Analysis of all the models of PV module is done with the help of MATLAB. This helps in comparison and proves the effectiveness of the recycled PV module based systems.

Cell-wall recycling and synthesis in Escherichia coli and Pseudomonas aeruginosa - their role in the development of resistance.

Science.gov (United States)

Dhar, Supurna; Kumari, Hansi; Balasubramanian, Deepak; Mathee, Kalai

2018-01-01

The bacterial cell-wall that forms a protective layer over the inner membrane is called the murein sacculus - a tightly cross-linked peptidoglycan mesh unique to bacteria. Cell-wall synthesis and recycling are critical cellular processes essential for cell growth, elongation and division. Both de novo synthesis and recycling involve an array of enzymes across all cellular compartments, namely the outer membrane, periplasm, inner membrane and cytoplasm. Due to the exclusivity of peptidoglycan in the bacterial cell-wall, these players are the target of choice for many antibacterial agents. Our current understanding of cell-wall biochemistry and biogenesis in Gram-negative organisms stems mostly from studies of Escherichia coli. An incomplete knowledge on these processes exists for the opportunistic Gram-negative pathogen, Pseudomonas aeruginosa. In this review, cell-wall synthesis and recycling in the various cellular compartments are compared and contrasted between E. coli and P. aeruginosa. Despite the fact that there is a remarkable similarity of these processes between the two bacterial species, crucial differences alter their resistance to β-lactams, fluoroquinolones and aminoglycosides. One of the common mediators underlying resistance is the amp system whose mechanism of action is closely associated with the cell-wall recycling pathway. The activation of amp genes results in expression of AmpC β-lactamase through its cognate regulator AmpR which further regulates multi-drug resistance. In addition, other cell-wall recycling enzymes also contribute to antibiotic resistance. This comprehensive summary of the information should spawn new ideas on how to effectively target cell-wall processes to combat the growing resistance to existing antibiotics.

Investigation of limiter recycling in the divertor tokamak ASDEX

International Nuclear Information System (INIS)

Wagner, F.

1981-08-01

A divertor experiment like the ASDEX tokamak is especially suited for studying ion recycling at a material limiter, because the plasma can alternatively be limited by a magnetic limiter (separatrix) or by a material limiter. The role of the material limiter in ion recycling is documented by observing the increase in charge exchange flux emitted at the limiter position, and the decrease in external gas input necessary to keep the plasma line density invariant, when the material limiter is moved to the plasma. Ion recycling occurs predominantly at the outside section of a ring limiter. The limiter material saturates shortly after the start of the discharge. About 60% of the total recycling occurs at the limiter, which is nearly 100% of the ion recycling. The remaining 40% of the total recycling is carried by charge exchange neutrals. Due to saturation, the recycling coefficient at the limiter is 1; the recycling coefficient of the charge exchange neutrals at the wall is approximately 0.5 giving rise to a total recycling coefficient of limiter discharges of 0.8-0.9. It is observed that the plasma resistivity increases when the material limiter is moved toward the separatrix. The increase in Zsub(eff) can tentatively be explained by proton sputtering. (orig.)

Origin, Utilization, and Recycling of Nucleosides in the Central Nervous System

Science.gov (United States)

Ipata, Piero Luigi

2011-01-01

The brain relies on the salvage of preformed purine and pyrimidine rings, mainly in the form of nucleosides, to maintain its nucleotide pool in the proper qualitative and quantitative balance. The transport of nucleosides from blood into neurons and glia is considered to be an essential prerequisite to enter their metabolic utilization in the…

Blue Box Plus Quinte regional recycling demonstration program

Energy Technology Data Exchange (ETDEWEB)

1992-08-01

The Blue Box Plus recycling program was established in September 1990 in the Quinte region of Ontario. The program was intended to develop the necessary operational information so that the existing program could expand to include mixed plastics, corrugated cardboard, and boxboard. Over 33,000 recycling boxes were distributed over an area covering 15 municipalities with a population base of 95,000. The program showed the willingness of the public to participate in recycling, but advertising and promotion of the program were critical for success. Separation of the recycled materials on the collection trucks was found to be a viable approach and more efficient than sorting at the recycling plant. Adding new materials to be recycled could be done efficiently, and operating costs were in line with those for other programs collecting fewer materials. A cooperative market development with industrial players opened up a new and expanding market for boxboard. 6 figs., 9 tabs.

17. Meeting municipal waste Magdeburg. Residual waste - recycling - resource; 17. Tagung Siedlungsabfallwirtschaft Magdeburg. Restabfall - Recycling - Ressource

Energy Technology Data Exchange (ETDEWEB)

Haase, Hartwig (ed.)

2012-11-01

Within the 17th meeting Waste Management at Residential Areas from 12th o 13th September, 2012 in Magdeburg (Federal Republic of Germany), the following lectures were held: (1) Opening Session - Waste management in Saxony-Anhalt (O. Aeikens); (2) World with future - the eco-social perspective (F.J. Radermacher); (3) Global commodity markets - rare earths and their recycling (I. Fahimi); (4) The further development of nearhousehold capture of recyclable materials (J. Seitel); (5) On the future of the disposal management (J. Balg); (6) Options for action for the future of the municipal waste management (A. Gosten); (7) Current models of the capture of recyclable materials in Germany (M. Kerkhoff); (8) The recycling bin as a pilot test in Hanover (R. Middendorf); (9) Position of BellandVision on the implementation of a unified recycling bin (J. Soelling); (10) What will change with the new Recycle Economy Law according to the material flows and waste treatment capacities? (H. Alwast); (11) Waste management plan Saxony-Anhalt - Current developments (S. Hagel); (12) Wastes from the thermal waste treatment - Risk potential and disposal (G.-R. Behr); (13) Landfill Mining - Contribution of the waste management to the securing of resources (K. Fricke); (14) Logistic process design and system design in the transport of wastes in developing countries using Serbia as an example (Z. Jovanovic); (15) Example of good practices in the subsequent use of landfills - Solar park Cracauer Anger (M. Harnack); (16) Ecoloop - energy efficient gasification in the limestone moving-bed (R. Moeller); (17) Utilization of waste and biomass as a resource? Only by means of an intelligent logistics. (S. Trojahn); (18) Renewable energy resources - Experiences of a network provider (J. Kempmann).

Multiple sclerosis: evaluation of purine nucleotide metabolism in central nervous system in association with serum levels of selected fat-soluble antioxidants.

Science.gov (United States)

Kuračka, Lubomír; Kalnovičová, Terézia; Kucharská, Jarmila; Turčáni, Peter

2014-01-01

In the pathogenesis of demyelinating diseases including multiple sclerosis (MS) an important role is played by oxidative stress. Increased energy requirements during remyelination of axons and mitochondria failure is one of the causes of axonal degeneration and disability in MS. In this context, we analyzed to what extent the increase in purine catabolism is associated with selected blood lipophilic antioxidants and if there is any association with alterations in serum levels of coenzyme Q10. Blood serum and cerebrospinal fluid (CSF) samples from 42 patients with diagnosed MS and 34 noninflammatory neurologic patients (control group) were analyzed. Compared to control group, MS patients had significantly elevated values of all purine nucleotide metabolites, except adenosine. Serum lipophilic antioxidants γ -tocopherol, β -carotene, and coenzyme Q10 for the vast majority of MS patients were deficient or moved within the border of lower physiological values. Serum levels of TBARS, marker of lipid peroxidation, were increased by 81% in the MS patients. The results indicate that the deficit of lipophilic antioxidants in blood of MS patients may have a negative impact on bioenergetics of reparative remyelinating processes and promote neurodegeneration.

Defense Waste Processing Facility Recycle Stream Evaporation

International Nuclear Information System (INIS)

STONE, MICHAEL

2006-01-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) stabilizes high level radioactive waste (HLW) by vitrification of the waste slurries. DWPF currently produces approximately five gallons of dilute recycle for each gallon of waste vitrified. This recycle stream is currently sent to the HLW tank farm at SRS where it is processed through the HLW evaporators with the concentrate eventually sent back to the DWPF for stabilization. Limitations of the HLW evaporators and storage space constraints in the tank farm have the potential to impact the operation of the DWPF and could limit the rate that HLW is stabilized. After an evaluation of various alternatives, installation of a dedicated evaporator for the DWPF recycle stream was selected for further evaluation. The recycle stream consists primarily of process condensates from the pretreatment and vitrification processes. Other recycle streams consist of process samples, sample line flushes, sump flushes, and cleaning solutions from the decontamination and filter dissolution processes. The condensate from the vitrification process contains some species, such as sulfate, that are not appreciably volatile at low temperature and could accumulate in the system if 100% of the evaporator concentrate was returned to DWPF. These species are currently removed as required by solids washing in the tank farm. The cleaning solutions are much higher in solids content than the other streams and are generated 5-6 times per year. The proposed evaporator would be required to concentrate the recycle stream by a factor of 30 to allow the concentrate to be recycled directly to the DWPF process, with a purge stream sent to the tank farm as required to prevent buildup of sulfate and similar species in the process. The overheads are required to meet stringent constraints to allow the condensate to be sent directly to an effluent treatment plant. The proposed evaporator would nearly de-couple the DWPF process from the

Evaluation of radioactive scrap metal recycling

International Nuclear Information System (INIS)

Nieves, L.A.; Chen, S.Y.; Kohout, E.J.; Nabelssi, B.; Tilbrook, R.W.; Wilson, S.E.

1995-12-01

This report evaluates the human health risks and environmental and socio-political impacts of options for recycling radioactive scrap metal (RSM) or disposing of and replacing it. Argonne National Laboratory (ANL) is assisting the US Department of Energy (DOE), Office of Environmental Restoration and Waste Management, Oak Ridge Programs Division, in assessing the implications of RSM management alternatives. This study is intended to support the DOE contribution to a study of metal recycling being conducted by the Task Group on Recycling and Reuse of the Organization for Economic Cooperation and Development. The focus is on evaluating the justification for the practice of recycling RSM, and the case of iron and steel scrap is used as an example in assessing the impacts. To conduct the evaluation, a considerable set of data was compiled and developed. Much of this information is included in this document to provide a source book of information

The feasibility of recycling contaminated concrete

International Nuclear Information System (INIS)

Ayers, K.W.; Corroon, W.; Parker, F.L.

1999-01-01

The changing mission of the Department of Energy along with the aging of many of its facilities has resulted in renewed emphasis on decontaminating and decommissioning surplus structures. Currently DOE is decontaminating some concrete and sending the clean material to C and D disposal facilities. In other instance, DOE is sending contaminated concrete to LLW disposal facilities. This paper examines the economic feasibility of decontaminating the concrete and recycling the rubble as clean aggregate. A probabilistic cost model was used to examine six potential recycling and disposal scenarios. The model predicted potential costs saving across the DOE complex of nearly one billion dollars. The ability of local markets to assimilate the recycled material was estimated for Washington, Idaho, Tennessee, New Mexico, and South Carolina. The relationships between a number of the economic model's variables were examined to develop operating ranges for initial managerial evaluation of recycling

Evaluation of radioactive scrap metal recycling

Energy Technology Data Exchange (ETDEWEB)

Nieves, L.A.; Chen, S.Y.; Kohout, E.J.; Nabelssi, B.; Tilbrook, R.W.; Wilson, S.E.

1995-12-01

This report evaluates the human health risks and environmental and socio-political impacts of options for recycling radioactive scrap metal (RSM) or disposing of and replacing it. Argonne National Laboratory (ANL) is assisting the US Department of Energy (DOE), Office of Environmental Restoration and Waste Management, Oak Ridge Programs Division, in assessing the implications of RSM management alternatives. This study is intended to support the DOE contribution to a study of metal recycling being conducted by the Task Group on Recycling and Reuse of the Organization for Economic Cooperation and Development. The focus is on evaluating the justification for the practice of recycling RSM, and the case of iron and steel scrap is used as an example in assessing the impacts. To conduct the evaluation, a considerable set of data was compiled and developed. Much of this information is included in this document to provide a source book of information.

The level of recycling operations in Botswana | Ketlogetswe ...

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