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Sample records for lithium modulates tryptophan

  1. Module of lithium divertor for KTM tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Lyublinski, I., E-mail: yublinski@yandex.ru [FSUE ' Red Star' , Moscow (Russian Federation); Vertkov, A.; Evtikhin, V.; Balakirev, V.; Ionov, D.; Zharkov, M. [FSUE ' Red Star' , Moscow (Russian Federation); Tazhibayeva, I. [IAE NNC RK, Kurchatov (Kazakhstan); Mirnov, S. [TRINITI, Troitsk, Moscow Region (Russian Federation); Khomiakov, S.; Mitin, D. [OJSC Dollezhal Institute, Moscow (Russian Federation); Mazzitelli, G. [ENEA RC Frascati (Italy); Agostini, P. [ENEA RC Brasimone (Italy)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Problems of PFE degradation, tritium accumulation and plasma pollution can be overcome by the use of liquid lithium-metal with low Z. Black-Right-Pointing-Pointer Capillary-porous system (CPS) - new material in which liquid lithium fill a solid matrix from porous material. Black-Right-Pointing-Pointer Lithium divertor module for KTM tokamak is under development. Black-Right-Pointing-Pointer Lithium filled tungsten felt is offered as the base plasma facing material of divertor. Black-Right-Pointing-Pointer Results of this project addresses to the progress in the field of fusion neutrons source and fusion energy source creation. - Abstract: Activity on projects of ITER and DEMO reactors has shown that solution of problems of divertor target plates and other plasma facing elements (PFEs) based on the solid plasma facing materials cause serious difficulties. Problems of PFE degradation, tritium accumulation and plasma pollution can be overcome by the use of liquid lithium-metal with low Z. Application of lithium will allow to create a self-renewal and MHD stable liquid metal surface of the in-vessel devices possessing practically unlimited service life; to reduce power flux due to intensive re-irradiation on lithium atoms in plasma periphery that will essentially facilitate a problem of heat removal from PFE; to reduce Z{sub eff} of plasma to minimally possible level close to 1; to exclude tritium accumulation, that is provided with absence of dust products and an opportunity of the active control of the tritium contents in liquid lithium. Realization of these advantages is based on use of so-called lithium capillary-porous system (CPS) - new material in which liquid lithium fill a solid matrix from porous material. The progress in development of lithium technology and also activity in lithium experiments in the tokamaks TFTR, T-11M, T-10, FTU, NSTX, HT-7 and stellarator TJ II permits of solving the problems in development of

  2. The Potential Role of Cannabinoids in Modulating Serotonergic Signaling by Their Influence on Tryptophan Metabolism

    Directory of Open Access Journals (Sweden)

    Dietmar Fuchs

    2010-08-01

    Full Text Available Phytocannabinoids present in Cannabis plants are well known to exert potent anti-inflammatory and immunomodulatory effects. Previously, we have demonstrated that the psychoactive D9-tetrahydrocannabinol (THC and the non-psychotropic cannabidiol (CBD modulate mitogen-induced Th1-type immune responses in peripheral blood mononuclear cells (PBMC. The suppressive effect of both cannabinoids on mitogen-induced tryptophan degradation mediated by indoleamine-2,3-dioxygenase (IDO, suggests an additional mechanism by which antidepressive effects of cannabinoids might be linked to the serotonergic system. Here, we will review the role of tryptophan metabolism in the course of cell mediated immune responses and the relevance of cannabinoids in serotonergic signaling. We conclude that in particular the non-psychotropic CBD might be useful for the treatment of mood disorders in patients with inflammatory diseases, since this cannabinoid seems to be safe and its effects on activation-induced tryptophan degradation by CBD were more potent as compared to THC.

  3. FDTD Method in the Analysis of Lithium Niobate Modulator

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Mach-Zehnder traveling-wave lithium niobate modulator is simulated by time domain finite difference (FDTD) method for different device geometry. The result is comparable to the reported value by finite element method.

  4. Lithium-Ion Batteries: Thermal Behaviour Investigation of Unbalanced Modules

    National Research Council Canada - National Science Library

    Odile Capron; Ahmadou Samba; Noshin Omar; Thierry Coosemans; Peter Vanden Bossche; Joeri VanMierlo

    2015-01-01

      In this paper, the thermal behaviour of an unbalanced battery module made of large lithium iron phosphate cylindrical cells of 18 Ah nominal capacity is investigated during its discharge with 18...

  5. Tryptophan hydroxylase is modulated by L-type calcium channels in the rat pineal gland.

    Science.gov (United States)

    Barbosa, Roseli; Scialfa, Julieta Helena; Terra, Ilza Mingarini; Cipolla-Neto, José; Simonneaux, Valérie; Afeche, Solange Castro

    2008-02-27

    Calcium is an important second messenger in the rat pineal gland, as well as cAMP. They both contribute to melatonin synthesis mediated by the three main enzymes of the melatonin synthesis pathway: tryptophan hydroxylase, arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase. The cytosolic calcium is elevated in pinealocytes following alpha(1)-adrenergic stimulation, through IP(3)-and membrane calcium channels activation. Nifedipine, an L-type calcium channel blocker, reduces melatonin synthesis in rat pineal glands in vitro. With the purpose of investigating the mechanisms involved in melatonin synthesis regulation by the L-type calcium channel, we studied the effects of nifedipine on noradrenergic stimulated cultured rat pineal glands. Tryptophan hydroxylase, arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase activities were quantified by radiometric assays and 5-hydroxytryptophan, serotonin, N-acetylserotonin and melatonin contents were quantified by HPLC with electrochemical detection. The data showed that calcium influx blockaded by nifedipine caused a decrease in tryptophan hydroxylase activity, but did not change either arylalkylamine N-acetyltransferase or hydroxyindole-O-methyltransferase activities. Moreover, there was a reduction of 5-hydroxytryptophan, serotonin, N-acetylserotonin and melatonin intracellular content, as well as a reduction of serotonin and melatonin secretion. Thus, it seems that the calcium influx through L-type high voltage-activated calcium channels is essential for the full activation of tryptophan hydroxylase leading to melatonin synthesis in the pineal gland.

  6. Status of design and experimental activity on module of lithium divertor for KTM tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Lyublinski, Igor E., E-mail: lyublinski@yandex.ru [JSC “Red Star”, Moscow (Russian Federation); Vertkov, Alexey V.; Zharkov, Mikhail Yu.; Semenov, Vladimir V. [JSC “Red Star”, Moscow (Russian Federation); Mirnov, Sergey V.; Lazarev, Vladimir B. [GSC RF TRINITI, Troitsk, Moscow Region (Russian Federation); Tazhibayeva, Irina L.; Shapovalov, Gennadiy V.; Kulsartov, Timur V.; D’yachenko, Alexandr V. [IAE of National Nuclear Center, Kurchatov (Kazakhstan); Mazzitelli, Giuseppe [Associazione EURATOM-ENEA sulla Fusione, C.R. ENEA Frascati, Rome (Italy); Agostini, Pietro [ENEA Brasimone, Camugnano, BO (Italy)

    2013-10-15

    Highlights: • Lithium divertor module based on capillary-porous system is created for KTM tokamak. • The hydraulic tests of lithium divertor module were conducted. • The results were compared with the calculation data. • The analysis of results’ discrepancies was conducted. • The lithium divertor module is ready for tests on KTM tokamak. -- Abstract: The projects of ITER and DEMO reactors showed that there are serious difficulties with solving the issues of plasma facing elements (PFE) based on the solid materials. Problems of PFE can be overcome by the use of liquid lithium. Application of lithium will allow to create a self-renewal and MHD stable liquid metal surface of the in-vessel devices possessing practically unlimited service life. Realization of these advantages is based on use of so-called lithium capillary-porous system (CPS) – new material, in which liquid lithium fills a solid matrix from porous material. The progress in development of lithium technology and also lithium experiments in the tokamaks TFTR, T-11M, T-10, FTU, NSTX, LTX, HT-7 and stellarator TJ II is a good basis for development of the project of steady-state operating lithium divertor module for Kazakhstan tokamak. At present the lithium divertor module for KTM tokamak is development and manufacturing. The paper describes main design features of the module of lithium divertor (MLD). The first step of the hydraulic tests of MLD with fully assembled external thermo-stabilization system, which was connected to in-vessel lithium unit, were performed using ethanol as a model heat transfer media. Test results of MLD have shown that operating parameters of designed and manufactured system for thermo-stabilization are sufficient for proper operation; basic hydraulic characteristics of the system are close to expected values.

  7. Lithium-Ion Batteries: Thermal Behaviour Investigation of Unbalanced Modules

    Directory of Open Access Journals (Sweden)

    Odile Capron

    2015-06-01

    Full Text Available In this paper, the thermal behaviour of an unbalanced battery module made of large lithium iron phosphate cylindrical cells of 18 Ah nominal capacity is investigated during its discharge with 18 A, 54 A and 90 A currents. For this study, several cells were assigned in the module to 5%, 10% and 20% initial depth of discharge (DoD. The thermal management of the cells in the module is achieved based on a forced air cooling. The computations of the temperature distribution inside the cells and the module are performed with a two-dimensional modelling approach. During the discharges, the cells with a non-zero initial DoD show a more pronounced temperature increase up to 5% compared to the reference cells. In the end of the three discharges, the highest temperatures 26.5 °C (18 A, 29.6 °C  (54 A and 32.3 °C  (90 A, respectively, are reached for the cells with the highest initial DoD. For these cells, with the increase in the current rate, the highest amount of total heat exceeds 25 W. The reactive and the active heats are found to be the main contributors to the total heat generated by the cells. This study provides the effect of the initial DoD of the cells on the temperature development occurring in an unbalanced battery module during its discharge.

  8. Tryptophan-2,3-dioxygenase (TDO) inhibition ameliorates neurodegeneration by modulation of kynurenine pathway metabolites

    Science.gov (United States)

    Breda, Carlo; Sathyasaikumar, Korrapati V.; Sograte Idrissi, Shama; Notarangelo, Francesca M.; Estranero, Jasper G.; Moore, Gareth G. L.; Green, Edward W.; Kyriacou, Charalambos P.; Schwarcz, Robert; Giorgini, Flaviano

    2016-01-01

    Metabolites of the kynurenine pathway (KP) of tryptophan (TRP) degradation have been closely linked to the pathogenesis of several neurodegenerative disorders. Recent work has highlighted the therapeutic potential of inhibiting two critical regulatory enzymes in this pathway—kynurenine-3-monooxygenase (KMO) and tryptophan-2,3-dioxygenase (TDO). Much evidence indicates that the efficacy of KMO inhibition arises from normalizing an imbalance between neurotoxic [3-hydroxykynurenine (3-HK); quinolinic acid (QUIN)] and neuroprotective [kynurenic acid (KYNA)] KP metabolites. However, it is not clear if TDO inhibition is protective via a similar mechanism or if this is instead due to increased levels of TRP—the substrate of TDO. Here, we find that increased levels of KYNA relative to 3-HK are likely central to the protection conferred by TDO inhibition in a fruit fly model of Huntington’s disease and that TRP treatment strongly reduces neurodegeneration by shifting KP flux toward KYNA synthesis. In fly models of Alzheimer’s and Parkinson’s disease, we provide genetic evidence that inhibition of TDO or KMO improves locomotor performance and ameliorates shortened life span, as well as reducing neurodegeneration in Alzheimer's model flies. Critically, we find that treatment with a chemical TDO inhibitor is robustly protective in these models. Consequently, our work strongly supports targeting of the KP as a potential treatment strategy for several major neurodegenerative disorders and suggests that alterations in the levels of neuroactive KP metabolites could underlie several therapeutic benefits. PMID:27114543

  9. Dietary tryptophan and methionine as modulators of European seabass (Dicentrarchus labrax) immune status and inflammatory response.

    Science.gov (United States)

    Machado, Marina; Azeredo, Rita; Díaz-Rosales, Patricia; Afonso, António; Peres, Helena; Oliva-Teles, Aires; Costas, Benjamín

    2015-02-01

    Amino acids regulate key metabolic pathways important to immune responses and their nutritional supply may increase synthesis of immune-related proteins. The present study aimed to evaluate the effects of dietary supplementation of tryptophan and methionine on European seabass (Dicentrarchus labrax) cellular and humoral status. The immunomodulatory effects of tryptophan and methionine during an inflammatory insult was also evaluated after intraperitoneal injection with inactivated Photobacterium damselae subsp. piscicida (Phdp). A practical isonitrogenous (45% crude protein) and isolipidic (16% crude fat) diets was formulated to include fish meal and a blend of plant feedstuffs as protein sources and fish oil as the main lipid source (CRL diet). Two other diets were formulated similar to the control but including L-tryptophan or L-methionine at ×2 the requirement level (diets TRP and MET, respectively). European seabass weighing 275 g were fed the experimental diets for a period of 15 days before being sampled (trial 1). Then, fish were subjected to a peritoneal inflammation by intraperitoneally injecting UV killed Phdp (10(6) colony forming units ml(-1)) and sampled following 4 and 24 h post-injection (trial 2). Fish injected with a saline solution served as control. The haematological profile, peripheral cell dynamics and several plasma immune parameters were determined in trials 1 and 2, whereas cell migration to the inflammatory focus was also determined in trial 2. MET positively affected European seabass immune status by improving the peripheral leucocyte response, complement activity and bactericidal capacity, a stronger cellular recruitment to the inflammatory focus, and higher plasma peroxidase and bactericidal activities. TRP also seemed to improve immunostimulation, as there was a trend to augment both cell-mediated immunity and humoral capacity. However, TRP failed to improve an inflammatory response, verified by a decrease in blood phagocyte numbers

  10. TrpM, a Small Protein Modulating Tryptophan Biosynthesis and Morpho-Physiological Differentiation in Streptomyces coelicolor A3(2)

    Science.gov (United States)

    Palazzotto, Emilia; Gallo, Giuseppe; Renzone, Giovanni; Giardina, Anna; Sutera, Alberto; Silva, Joohee; Vocat, Celinè; Botta, Luigi; Scaloni, Andrea; Puglia, Anna Maria

    2016-01-01

    In the model actinomycete Streptomyces coelicolor A3(2), small open reading frames encoding proteins with unknown functions were identified in several amino acid biosynthetic gene operons, such as SCO2038 (trpX) in the tryptophan trpCXBA locus. In this study, the role of the corresponding protein in tryptophan biosynthesis was investigated by combining phenotypic and molecular analyses. The 2038KO mutant strain was characterized by delayed growth, smaller aerial hyphae and reduced production of spores and actinorhodin antibiotic, with respect to the WT strain. The capability of this mutant to grow on minimal medium was rescued by tryptophan and tryptophan precursor (serine and/or indole) supplementation on minimal medium and by gene complementation, revealing the essential role of this protein, here named TrpM, as modulator of tryptophan biosynthesis. His-tag pull-down and bacterial adenylate cyclase-based two hybrid assays revealed TrpM interaction with a putative leucyl-aminopeptidase (PepA), highly conserved component among various Streptomyces spp. In silico analyses showed that PepA is involved in the metabolism of serine, glycine and cysteine through a network including GlyA, CysK and CysM enzymes. Proteomic experiments suggested a TrpM-dependent regulation of metabolic pathways and cellular processes that includes enzymes such as GlyA, which is required for the biosynthesis of tryptophan precursors and key proteins participating in the morpho-physiological differentiation program. Altogether, these findings reveal that TrpM controls tryptophan biosynthesis at the level of direct precursor availability and, therefore, it is able to exert a crucial effect on the morpho-physiological differentiation program in S. coelicolor A3(2). PMID:27669158

  11. Lithium

    Science.gov (United States)

    Jaskula, B.W.

    2012-01-01

    In 2011, world lithium consumption was estimated to have been about 25 kt (25,000 st) of lithium contained in minerals and compounds, a 10-percent increase from 2010. U.S. consumption was estimated to have been about 2 kt (2,200 st) of contained lithium, a 100-percent increase from 2010. The United States was estimated to be the fourth-ranked consumer of lithium and remained the leading importer of lithium carbonate and the leading producer of value-added lithium materials. One company, Chemetall Foote Corp. (a subsidiary of Chemetall GmbH of Germany), produced lithium compounds from domestic brine resources near Silver Peak, NV.

  12. Novel intercore-cladding lithium niobate thin film coated MOEMS fiber sensor/modulator

    Science.gov (United States)

    Jamlson, Tracee L.; Konreich, Phillip; Yu, Chung

    2005-01-01

    A MOEMS fiber modulator/sensor is fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125-micron fibers. Such a MOEMS modulator design is expected to enhance existing lithium niobate undersea acousto-optic sound wave detectors. In our proposed version, the lithium niobate thin film alters the ordinary silica core/cladding boundary conditions such that, when a stress or strain is applied to the fiber, the core light confinement factor changes, leading to modulation of fiber light transmission. Test results of the lithium niobate embedded fiber with a 1550-nm, 4-mW laser source revealed a reduction in light transmission with applied tension. As a comparison, using the same laser source, an ordinary silica core/cladding fiber did not exhibit any reduction in transmitted light when the same strain was applied. Further experimental work and theoretical analysis is ongoing.

  13. Novel intercore-cladding lithium niobate thin film coated MOEMS fiber sensor/modulator

    Science.gov (United States)

    Jamlson, Tracee L.; Konreich, Phillip; Yu, Chung

    2005-01-01

    A MOEMS fiber modulator/sensor is fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125-micron fibers. Such a MOEMS modulator design is expected to enhance existing lithium niobate undersea acousto-optic sound wave detectors. In our proposed version, the lithium niobate thin film alters the ordinary silica core/cladding boundary conditions such that, when a stress or strain is applied to the fiber, the core light confinement factor changes, leading to modulation of fiber light transmission. Test results of the lithium niobate embedded fiber with a 1550-nm, 4-mW laser source revealed a reduction in light transmission with applied tension. As a comparison, using the same laser source, an ordinary silica core/cladding fiber did not exhibit any reduction in transmitted light when the same strain was applied. Further experimental work and theoretical analysis is ongoing.

  14. A Novel Inter Core-Cladding Lithium Niobate Thin Film Coated Fiber Modulator/Sensor

    Science.gov (United States)

    Jamison, Tracee L.; Komriech, Phillip; Yu, Chung

    2004-01-01

    A fiber modulator/sensor has been fabricated by depositing a lithium niobate sol-gel thin film between the core and cladding of a fiber preform. The preform is then drawn into 125 micron fiber. The proposed design of lithium niobate cylinder fibers can enhance the existing methodology for detecting sound waves under water utilizing the acoustooptic properties of lithium niobate. Upon application of a stress or strain, light propagating inside the core, according to the principle of total internal reflection, escapes, into the cladding because of the photoelastic boundary layer of lithium niobate. Test results of the lithium niobate fiber reveal a reduction in the 1550 nm, 4mW source with applied tension. The source power from an ordinary quartz fiber under the same stress condition remained invariant to applied tension.

  15. Modulating the activity of short arginine-tryptophan containing antibacterial peptides with N-terminal metallocenoyl groups

    Directory of Open Access Journals (Sweden)

    H. Bauke Albada

    2012-10-01

    Full Text Available A series of small synthetic arginine and tryptophan containing peptides was prepared and analyzed for their antibacterial activity. The effect of N-terminal substitution with metallocenoyl groups such as ferrocene (FcCO and ruthenocene (RcCO was investigated. Antibacterial activity in different media, growth inhibition, and killing kinetics of the most active peptides were determined. The toxicity of selected derivatives was determined against erythrocytes and three human cancer cell lines. It was shown that the replacement of an N-terminal arginine residue with a metallocenoyl moiety modulates the activity of WRWRW-peptides against Gram-positive and Gram-negative bacteria. MIC values of 2–6 µM for RcCO-W(RW2 and 1–11 µM for (RW3 were determined. Interestingly, W(RW2-peptides derivatized with ferrocene were significantly less active than those derivatized with ruthenocene which have similar structural but different electronic properties, suggesting a major influence of the latter. The high activities observed for the RcCO-W(RW2- and (RW3-peptides led to an investigation of the origin of activity of these peptides using several important activity-related parameters. Firstly, killing kinetics of the RcCO-W(RW2-peptide versus killing kinetics of the (RW3 derivative showed faster reduction of the colony forming units for the RcCO-W(RW2-peptide, although MIC values indicated higher activity for the (RW3-peptide. This was confirmed by growth inhibition studies. Secondly, hemolysis studies revealed that both peptides did not lead to significant destruction of erythrocytes, even up to 500 µg/mL for (RW3 and 250 µg/mL for RcCO-W(RW2. In addition, toxicity against three human cancer cell lines (HepG2, HT29, MCF7 showed that the (RW3-peptide had an IC50 value of ~140 µM and the RcW(RW2 one of ~90 µM, indicating a potentially interesting therapeutic window. Both the killing kinetics and growth inhibition studies presented in this work point to a

  16. Modulating the activity of short arginine-tryptophan containing antibacterial peptides with N-terminal metallocenoyl groups.

    Science.gov (United States)

    Albada, H Bauke; Chiriac, Alina-Iulia; Wenzel, Michaela; Penkova, Maya; Bandow, Julia E; Sahl, Hans-Georg; Metzler-Nolte, Nils

    2012-01-01

    A series of small synthetic arginine and tryptophan containing peptides was prepared and analyzed for their antibacterial activity. The effect of N-terminal substitution with metallocenoyl groups such as ferrocene (FcCO) and ruthenocene (RcCO) was investigated. Antibacterial activity in different media, growth inhibition, and killing kinetics of the most active peptides were determined. The toxicity of selected derivatives was determined against erythrocytes and three human cancer cell lines. It was shown that the replacement of an N-terminal arginine residue with a metallocenoyl moiety modulates the activity of WRWRW-peptides against Gram-positive and Gram-negative bacteria. MIC values of 2-6 µM for RcCO-W(RW)(2) and 1-11 µM for (RW)(3) were determined. Interestingly, W(RW)(2)-peptides derivatized with ferrocene were significantly less active than those derivatized with ruthenocene which have similar structural but different electronic properties, suggesting a major influence of the latter. The high activities observed for the RcCO-W(RW)(2)- and (RW)(3)-peptides led to an investigation of the origin of activity of these peptides using several important activity-related parameters. Firstly, killing kinetics of the RcCO-W(RW)(2)-peptide versus killing kinetics of the (RW)(3) derivative showed faster reduction of the colony forming units for the RcCO-W(RW)(2)-peptide, although MIC values indicated higher activity for the (RW)(3)-peptide. This was confirmed by growth inhibition studies. Secondly, hemolysis studies revealed that both peptides did not lead to significant destruction of erythrocytes, even up to 500 µg/mL for (RW)(3) and 250 µg/mL for RcCO-W(RW)(2). In addition, toxicity against three human cancer cell lines (HepG2, HT29, MCF7) showed that the (RW)(3)-peptide had an IC(50) value of ~140 µM and the RcW(RW)(2) one of ~90 µM, indicating a potentially interesting therapeutic window. Both the killing kinetics and growth inhibition studies presented in

  17. Lithium

    Science.gov (United States)

    Lithium is used to treat and prevent episodes of mania (frenzied, abnormally excited mood) in people with bipolar disorder (manic-depressive disorder; a disease that causes episodes of depression, episodes of mania, and other abnormal ...

  18. Thermal analysis of lithium cooled natural circulation loop module for fuel rod testing in the Fast Flux Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Eyler, L.L.; Kim, D.; Stover, R.L.; Beaver, T.R.

    1987-01-01

    Maximum heat removal capability of a lithium cooled natural circulation fuel rod test module design is determined. Loop geometry is optimized within limitations of design specifications for nominal operation temperatures, materials, and test module environment. Results provide test module operation limits and range of potential uncertainties. 3 refs., 12 figs.

  19. Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation

    Science.gov (United States)

    Tang, Liang; Cheng, Pengle

    2017-01-01

    Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic–plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis. PMID:28746390

  20. Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation.

    Science.gov (United States)

    Tang, Liang; Zhang, Jinjie; Cheng, Pengle

    2017-01-01

    Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic-plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis.

  1. Phase Regeneration of a BPSK Data Signal Using a Lithium Niobate Phase Modulator

    DEFF Research Database (Denmark)

    Mulvad, Hans Christian Hansen; Da Ros, Francesco; Galili, Michael

    2015-01-01

    We propose a scheme for phase regeneration of an optical binary phase shift keying (BPSK) data signal using a Lithium Niobate (LiNbO3) phase modulator. The scheme is based on heterodyne detection of the BPSK data signal with a continuous wave local oscillator (CW-LO). Carrier recovery...... is then achieved in the electrical domain using a ×2 frequency-multiplier and a narrow-band filtering scheme. Subsequently, a superposition of the recovered carrier and the heterodyne detected data signal is used to modulate the CW-LO in a LiNbO3 phase modulator. The result is a parametric mixing process...... in the optical domain, leading to a phase-regenerated BPSK data signal by the coherent superposition with a phase-inverted copy. The proposed scheme constitutes a compact and stable setup, where active phase-stabilization of the electrical data- and carrier-paths can potentially be avoided. An analytical...

  2. Quercetin and lithium chloride modulate Wnt signaling in pluripotent embryonal carcinoma NT2/D1 cells

    Directory of Open Access Journals (Sweden)

    Mojsin Marija

    2013-01-01

    Full Text Available Wnt signaling functions in numerous cellular activities such as cell fate determination, patterning, and migration in embryogenesis, apoptosis, etc. In this study, we used quercetin and lithium chloride to investigate modulations of the Wnt signaling pathway in human pluripotent embryonal carcinoma NT2/D1 cell line. First, we optimized conditions for NT2/D1 cell treatments with quercetin and lithium chloride and assessed their cytotoxic effects on the cells, cell viability and proliferation rate. Our results showed that induction of cell death by quercetin and LiCl is p53-dependent in NT2/D cells. We also examined the degree of Wnt signaling modulations by analyzing the expression of c-myc, a wellknown Wnt signaling target gene. Since the retinoic acid induction of NT2/D1 cells is good in an in vitro model system for human neural differentiation, studying Wnt signaling modulation in NT2/D1 would contribute to a better understanding of the mechanisms involved in neural stem cell maintenance and human neural development. [Projekat Ministarstva nauke Republike Srbije, br. 173051

  3. Modelling the impact of variations in electrode manufacturing on lithium-ion battery modules

    Science.gov (United States)

    Kenney, Ben; Darcovich, Ken; MacNeil, Dean D.; Davidson, Isobel J.

    2012-09-01

    The performance of a lithium-ion battery is closely related to its manufacturing and can be impacted by variability in the electrodes. Typically, manufacturers must set aside cells which are deemed to be of insufficient quality, thus contributing to the cost of manufacturing high quality cells. The performance of a lithium-ion battery module, that is, a string of cells configured in series, depends on the performance of the weakest cell. In this work, the single particle model was adapted to simulate the coupled behaviour of an arbitrary number of cells configured in series. The impact of slight variations in the manufacturing of electrodes was then investigated with a goal of linking electrode properties such as variations in thickness, electrode density and active material weight fraction with the performance of battery modules made from these cells. Results indicate that the initial capacity, the rate of capacity fade and other important aspects such as the distribution of state-of-charge from one cell to another depends on the extent of variability in the manufacturing of the electrodes. In this work, the variation in the performance of the module has been quantified as a function of manufacturing variation at the electrode level.

  4. Lithium modulates the chronic stress-induced effect on blood glucose level of male rats

    Directory of Open Access Journals (Sweden)

    Popović Nataša

    2010-01-01

    Full Text Available In the present study we examined gross changes in the mass of whole adrenal glands and that of the adrenal cortex, as well as the serum corticosterone and glucose level of mature male Wistar rats subjected to three different treatments: animals subjected to chronic restraint-stress, animals injected with lithium (Li and chronically stressed rats treated with Li. Under all three conditions we observed hypertrophy of whole adrenals, as well as the adrenal cortices. Chronic restraint stress, solely or in combination with Li treatment, significantly elevated the corticosterone level, but did not change the blood glucose level. Animals treated only with Li exhibited an elevated serum corticosterone level and blood glucose level. The aim of our study was to investigate the modulation of the chronic stress-induced effect on the blood glucose level by lithium, as a possible mechanism of avoiding the damage caused by chronic stress. Our results showed that lithium is an agent of choice which may help to reduce stress-elevated corticosterone and replenish exhausted glucose storages in an organism.

  5. A Thermal Runaway Simulation on a Lithium Titanate Battery and the Battery Module

    Directory of Open Access Journals (Sweden)

    Man Chen

    2015-01-01

    Full Text Available Based on the electrochemical and thermal model, a coupled electro-thermal runaway model was developed and implemented using finite element methods. The thermal decomposition reactions when the battery temperature exceeds the material decomposition temperature were embedded into the model. The temperature variations of a lithium titanate battery during a series of charge-discharge cycles under different current rates were simulated. The results of temperature and heat generation rate demonstrate that the greater the current, the faster the battery temperature is rising. Furthermore, the thermal influence of the overheated cell on surrounding batteries in the module was simulated, and the variation of temperature and heat generation during thermal runaway was obtained. It was found that the overheated cell can induce thermal runaway in other adjacent cells within 3 mm distance in the battery module if the accumulated heat is not dissipated rapidly.

  6. TRYPTOPHAN PROMOTES CHARITABLE DONATING

    Directory of Open Access Journals (Sweden)

    Laura eSteenbergen

    2014-12-01

    Full Text Available The link between serotonin (5-HT and one of the most important elements of prosocial behavior, charity, has remained largely uninvestigated. In the present study, we tested whether charitable donating can be promoted by administering the food supplement L-Tryptophan (TRP, the biochemical precursor of 5-HT. Participants were compared with respect to the amount of money they donated when given the opportunity to make a charitable donation. As expected, compared to a neutral placebo, TRP appears to increase the participants’ willingness to donate money to a charity. This result supports the idea that the food we eat may act as a cognitive enhancer modulating the way we think and perceive the world and others.

  7. Modulating the direction of carbon flow in Escherichia coli to improve l-tryptophan production by inactivating the global regulator FruR.

    Science.gov (United States)

    Liu, Lina; Duan, Xuguo; Wu, Jing

    2016-08-10

    The fructose repressor (FruR) affects carbon flux through the central metabolic pathways of Escherichia coli. In this study, l-tryptophan production in Escherichia coli FB-04 was improved by knocking out the fruR gene, thereby inactivating FruR. This fruR knockout strain, E. coli FB-04(ΔfruR), not only exhibited higher growth efficiency, it also showed substantially improved l-tryptophan production. l-tryptophan production by E. coli FB-04(ΔfruR) and l-tryptophan yield per glucose were increased by 62.5% and 52.4%, respectively, compared with the parent E. coli FB-04. Metabolomics analysis showed that the fruR knockout significantly enhances metabolic flow through glycolysis, the pentose phosphate pathway and the TCA cycle, increasing levels of critical precursors and substrates for l-tryptophan biosynthesis. These results indicate that fruR deletion should enhance l-tryptophan production and improve the efficiency of carbon source utilization independent of genetic background.

  8. Safety analysis of the US dual coolant liquid lead lithium ITER test blanket module

    Science.gov (United States)

    Merrill, Brad; Reyes, Susana; Sawan, Mohamed; Wong, Clement

    2007-07-01

    The US is proposing a prototype of a dual coolant liquid lead-lithium DEMO blanket concept for testing in the International Thermonuclear Experimental Reactor (ITER) as an ITER test blanket module (TBM). Because safety considerations are an integral part of the design process to ensure that this TBM does not adversely impact the safety of ITER, a safety assessment has been conducted for this TBM and its ancillary systems as requested by the ITER project. Four events were selected by the ITER international team (IT) to address specific reactor safety concerns, such as vaccum vessel (VV) pressurization, confinement building pressure build-up, TBM decay heat removal capability, tritium and activation products release from the TBM system and hydrogen and heat production from chemical reactions. This paper summarizes the results of this safety assessment conducted with the MELCOR computer code.

  9. Rocking-chair configuration in ultrathin lithium vanadate-graphene hybrid nanosheets for electrical modulation.

    Science.gov (United States)

    Zhu, Haiou; Qin, Xinming; Sun, Xu; Yan, Wensheng; Yang, Jinlong; Xie, Yi

    2013-01-01

    The ability to control electronic property of a material by externally applied voltage is greatly anticipated in modern electronics, and graphene provide potential application foreground for this issue on account of its exotic ambipolar transport property. In this study, we proposed that inorganic-graphene intercalated nanosheet is an effective solution to optimize the transport property of graphene. As an example, lithium vanadate-graphene (LiVO-graphene) alternately intercalated nanosheets were designed and successfully synthesized. Theoretical calculation implied that its rocking chair configuration may provide a new pathway to switch the carrier in graphene layer between p-type and n-type while the position of embedded Li ions is controlled by an external field. Thus, a demo transistor was fabricated with layer-by-layer overlapping of LiVO-graphene nanosheets which proved that this inorganic-graphene structure could be used for electrical modulation in electronic devices.

  10. Thermo-Mechanical Analyses of the High Heat Flux Component for ITER Dual Functional Lithium Lead Test Blanket Module

    Institute of Scientific and Technical Information of China (English)

    CHEN Hongli; BAI Yunqing

    2009-01-01

    The finite element code ANSYS is used to calculate the temperature and stress distributions for the first wall of DFLL-TBM (dual functional lithium lead-test blanket module),for testing in ITER. Preliminary analyses indicate that not only the low temperature design rules,the well-known 3Sm rules, are satisfied for the first wall, but the additional high temperature structural design criteria for the creep damage limits and creep-ratcheting limits are met as well.

  11. L-tryptophan

    Science.gov (United States)

    ... has been linked to over 1500 reports of eosinophilia-myalgia syndrome (EMS) and 37 deaths. EMS is ... breast-feeding. A white blood cell disorder called eosinophilia: L-tryptophan might make this condition worse. L- ...

  12. Tryptophan catabolizing enzymes – party of three

    Directory of Open Access Journals (Sweden)

    Helen J Ball

    2014-10-01

    Full Text Available Indoleamine 2,3-dioxygenase (IDO and tryptophan 2,3-dioxygenase (TDO are tryptophan-degrading enzymes that have independently evolved to catalyze the first step in tryptophan catabolism via the kynurenine pathway. The depletion of tryptophan and formation of kynurenine pathway metabolites modulates the activity of the mammalian immune, reproductive and central nervous systems. IDO and TDO enzymes can have overlapping or distinct functions depending on their expression patterns. The expression of TDO and IDO enzymes in mammals differs not only by tissue/cellular localization but also by their induction by distinct stimuli. To add to the complexity, these genes also have undergone duplications in some organisms leading to multiple isoforms of IDO or TDO. For example, many vertebrates, including all mammals, have acquired two IDO genes via gene duplication, although the IDO1-like gene has been lost in some lower vertebrate lineages. Gene duplications can allow the homologs to diverge and acquire different properties to the original gene. There is evidence for IDO enzymes having differing enzymatic characteristics, signaling properties and biological functions. This review analyses the evolutionary convergence of IDO and TDO enzymes as tryptophan-catabolizing enzymes and the divergent evolution of IDO homologs to generate an enzyme family with diverse characteristics not possessed by TDO enzymes, with an emphasis on the immune system.

  13. Interpretation of Simultaneous Mechanical-Electrical-Thermal Failure in a Lithium-Ion Battery Module: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao; Santhanagopalan, Shriram; Stock, Mark J.; Brunhart-Lupo, Nicholas; Gruchalla, Kenny

    2016-12-01

    Lithium-ion batteries are currently the state-of- the-art power sources for electric vehicles, and their safety behavior when subjected to abuse, such as a mechanical impact, is of critical concern. A coupled mechanical-electrical-thermal model for simulating the behavior of a lithium-ion battery under a mechanical crush has been developed. We present a series of production-quality visualizations to illustrate the complex mechanical and electrical interactions in this model.

  14. Calcium Channel Genes Associated with Bipolar Disorder Modulate Lithium's Amplification of Circadian Rhythms

    Science.gov (United States)

    McCarthy, Michael J.; LeRoux, Melissa; Wei, Heather; Beesley, Stephen; Kelsoe, John R.; Welsh, David K.

    2015-01-01

    Bipolar disorder (BD) is associated with mood episodes and low amplitude circadian rhythms. Previously, we demonstrated that fibroblasts grown from BD patients show weaker amplification of circadian rhythms by lithium compared to control cells. Since calcium signals impact upon the circadian clock, and L-type calcium channels (LTCC) have emerged as genetic risk factors for BD, we examined whether loss of function in LTCCs accounts for the attenuated response to lithium in BD cells. We used fluorescent dyes to measure Ca2+ changes in BD and control fibroblasts after lithium treatment, and bioluminescent reporters to measure Per2∷luc rhythms in fibroblasts from BD patients, human controls, and mice while pharmacologically or genetically manipulating calcium channels. Longitudinal expression of LTCC genes (CACNA1C, CACNA1D and CACNB3) was then measured over 12-24 hr in BD and control cells. Our results indicate that independently of LTCCs, lithium stimulated intracellular Ca2+ less effectively in BD vs. control fibroblasts. In longitudinal studies, pharmacological inhibition of LTCCs or knockdown of CACNA1A, CACNA1C, CACNA1D and CACNB3 altered circadian rhythm amplitude. Diltiazem and knockdown of CACNA1C or CACNA1D eliminated lithium's ability to amplify rhythms. Knockdown of CACNA1A or CACNB3 altered baseline rhythms, but did not affect rhythm amplification by lithium. In human fibroblasts, CACNA1C genotype predicted the amplitude response to lithium, and the expression profiles of CACNA1C, CACNA1D and CACNB3 were altered in BD vs. controls. We conclude that in cells from BD patients, calcium signaling is abnormal, and that LTCCs underlie the failure of lithium to amplify circadian rhythms. PMID:26476274

  15. Acute tryptophan depletion increases translational indices of anxiety but not fear: serotonergic modulation of the bed nucleus of the stria terminalis?

    Science.gov (United States)

    Robinson, Oliver J; Overstreet, Cassie; Allen, Phillip S; Pine, Daniel S; Grillon, Christian

    2012-07-01

    Serotonin is strongly implicated in the mammalian stress response, but surprisingly little is known about its mode of action. Recent data suggest that serotonin can inhibit aversive responding in humans, but this remains underspecified. In particular, data in rodents suggest that global serotonin depletion may specifically increase long-duration bed nucleus of the stria terminalis (BNST)-mediated aversive responses (ie, anxiety), but not short-duration BNST-independent responses (ie, fear). Here, we extend these findings to humans. In a balanced, placebo-controlled crossover design, healthy volunteers (n=20) received a controlled diet with and without the serotonin precursor tryptophan (acute tryptophan depletion; ATD). Aversive states were indexed by translational acoustic startle measures. Fear and anxiety were operationally defined as the increase in startle reactivity during short- and long-duration threat periods evoked by predictable shock (fear-potentiated startle) and by the context in which the shocks were administered (anxiety-potentiated startle), respectively. ATD significantly increased long-duration anxiety-potentiated startle but had no effect on short-duration fear-potentiated startle. These results suggest that serotonin depletion in humans selectively increases anxiety but not fear. Current translational frameworks support the proposition that ATD thus disinhibits dorsal raphé-originating serotonergic control of corticotropin-releasing hormone-mediated excitation of the BNST. This generates a candidate neuropharmacological mechanism by which depleted serotonin may increase response to sustained threats, alongside clear implications for our understanding of the manifestation and treatment of mood and anxiety disorders.

  16. Tryptophan oxygenation: mechanistic considerations.

    Science.gov (United States)

    Naismith, James H

    2012-06-01

    From a protein structural viewpoint, tryptophan is often considered an inert structural amino acid, playing a role as a hydrophobic anchor in membrane proteins or as part of the hydrophobic core of soluble proteins. However, tryptophan is the only polyaromatic amino acid and, from a chemical viewpoint, possesses unique reactivity owing to the electron-richness of the indole system. This reactivity is seen in the area of natural products and metabolites which have exquisite modifications of the indole ring system. Enzymes have evolved multiple strategies to break or modify the indole ring; one particular class is the IDO/TDO (indoleamine/tryptophan dioxygenase) superfamily. A new member of this family, PrnB, on the surface catalyses a very different reaction, but actually shares much of the early chemistry with the tryptophan dioxygenases. Studies on PrnB have contributed to our understanding of the wider superfamily. In the present mini-review, recent developments in our understanding of how the TDO class of enzymes use activated molecular oxygen to break the indole ring are discussed.

  17. Design and parametric optimization of thermal management of lithium-ion battery module with reciprocating air-flow

    Institute of Scientific and Technical Information of China (English)

    刘燕平; 欧阳陈志; 江清柏; 梁波

    2015-01-01

    Single cell temperature difference of lithium-ion battery (LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics (CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.

  18. Rotational spectrum of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, M. Eugenia, E-mail: maria.sanz@kcl.ac.uk; Cabezas, Carlos, E-mail: ccabezas@qf.uva.es; Mata, Santiago, E-mail: santiago.mata@uva.es; Alonso, Josè L., E-mail: jlalonso@qf.uva.es [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, 47011 Valladolid (Spain)

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  19. Rotational Spectrum of Tryptophan

    Science.gov (United States)

    Sanz, M. Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, José L.

    2014-06-01

    The rotational spectrum of the natural amino acid tryptophan has been observed using a recently constructed LA-MB-FTMW spectrometer, specifically designed to optimize the detection of heavier molecules at a lower frequency range. Independent analyses of the rotational spectra of individual conformers have conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The experimental values of the 14N nuclear quadrupole coupling constants have been found capital in the discrimination of the conformers. Both observed conformers are stabilized by a O-H\\cdotsN hydrogen bond in the side chain and a N-H\\cdotsπ interaction forming a chain that reinforces the strength of hydrogen bonds through cooperative effects.

  20. Molecular Signatures of Psychosocial Stress and Cognition Are Modulated by Chronic Lithium Treatment.

    Science.gov (United States)

    Brzózka, Magdalena M; Havemann-Reinecke, Ursula; Wichert, Sven P; Falkai, Peter; Rossner, Moritz J

    2016-07-01

    Chronic psychosocial stress is an important environmental risk factor of psychiatric diseases such as schizophrenia. Social defeat in rodents has been shown to be associated with maladaptive cellular and behavioral consequences including cognitive impairments. Although gene expression changes upon psychosocial stress have been described, a comprehensive transcriptome profiling study at the global level in precisely defined hippocampal subregions which are associated with learning has been lacking. In this study, we exposed adult C57Bl/6N mice for 3 weeks to "resident-intruder" paradigm and combined laser capture microdissection with microarray analyses to identify transcriptomic signatures of chronic psychosocial stress in dentate gyrus and CA3 subregion of the dorsal hippocampus. At the individual transcript level, we detected subregion specific stress responses whereas gene set enrichment analyses (GSEA) identified several common pathways upregulated upon chronic psychosocial stress related to proteasomal function and energy supply. Behavioral profiling revealed stress-associated impairments most prominent in fear memory formation which was prevented by chronic lithium treatment. Thus, we again microdissected the CA3 region and performed global transcriptome analysis to search for molecular signatures altered by lithium treatment in stressed animals. By combining GSEA with unsupervised clustering, we detected pathways that are regulated by stress and lithium in the CA3 region of the hippocampus including proteasomal components, oxidative phosphorylation, and anti-oxidative mechanisms. Our study thus provides insight into hidden molecular phenotypes of chronic psychosocial stress and lithium treatment and proves a beneficial role for lithium treatment as an agent attenuating negative effects of psychosocial stress on cognition.

  1. Glycogen synthase kinase 3β dictates podocyte motility and focal adhesion turnover by modulating paxillin activity: implications for the protective effect of low-dose lithium in podocytopathy.

    Science.gov (United States)

    Xu, Weiwei; Ge, Yan; Liu, Zhihong; Gong, Rujun

    2014-10-01

    Aberrant focal adhesion turnover is centrally involved in podocyte actin cytoskeleton disorganization and foot process effacement. The structural and dynamic integrity of focal adhesions is orchestrated by multiple cell signaling molecules, including glycogen synthase kinase 3β (GSK3β), a multitasking kinase lately identified as a mediator of kidney injury. However, the role of GSK3β in podocytopathy remains obscure. In doxorubicin (Adriamycin)-injured podocytes, lithium, a GSK3β inhibitor and neuroprotective mood stabilizer, obliterated the accelerated focal adhesion turnover, rectified podocyte hypermotility, and restored actin cytoskeleton integrity. Mechanistically, lithium counteracted the doxorubicin-elicited GSK3β overactivity and the hyperphosphorylation and overactivation of paxillin, a focal adhesion-associated adaptor protein. Moreover, forced expression of a dominant negative kinase dead mutant of GSK3β highly mimicked, whereas ectopic expression of a constitutively active GSK3β mutant abolished, the effect of lithium in doxorubicin-injured podocytes, suggesting that the effect of lithium is mediated, at least in part, through inhibition of GSK3β. Furthermore, paxillin interacted with GSK3β and served as its substrate. In mice with doxorubicin nephropathy, a single low dose of lithium ameliorated proteinuria and glomerulosclerosis. Consistently, lithium therapy abrogated GSK3β overactivity, blunted paxillin hyperphosphorylation, and reinstated actin cytoskeleton integrity in glomeruli associated with an early attenuation of podocyte foot process effacement. Thus, GSK3β-modulated focal adhesion dynamics might serve as a novel therapeutic target for podocytopathy.

  2. Interface-modulated approach toward multilevel metal oxide nanotubes for lithium-ion batteries and oxygen reduction reaction

    Institute of Scientific and Technical Information of China (English)

    Jiashen Meng; Chaojiang Niu; Xiong Liu; Ziang Liu; Hongliang Chen; Xuanpeng Wang; Jiantao Li

    2016-01-01

    Metal oxide hollow structures with multilevel interiors are of great interest for potential applications such as catalysis,chemical sensing,drug delivery,and energy storage.However,the controlled synthesis of multilevel nanotubes remains a great challenge.Here we develop a facile interface-modulated approach toward the synthesis of complex metal oxide multilevel nanotubes with tunable interior structures through electrospinning followed by controlled heat treatment.This versatile strategy can be effectively applied to fabricate wire-in-tube and tubein-tube nanotubes of various metal oxides.These multilevel nanotubes possess a large specific surface area,fast mass transport,good strain accommodation,and high packing density,which are advantageous for lithium-ion batteries (LIBs)and the oxygen reduction reaction (ORR).Specifically,shrinkable CoMn2O4 tube-in-tube nanotubes as a lithium-ion battery anode deliver a high discharge capacity of ~565 mAh.g-1 at a high rate of 2 A.g-1,maintaining 89% of the latter after 500 cycles.Further,as an oxygen reduction reaction catalyst,these nanotubes also exhibit excellent stability with about 92% current retention after 30,000 s,which is higher than that of commercial Pt/C (81%).Therefore,this feasible method may push the rapid development of one-dimensional (1D) nanomaterials.These multifunctional nanotubes have great potential in many frontier fields.

  3. Lithium and valproate modulate antioxidant enzymes and prevent ouabain-induced oxidative damage in an animal model of mania.

    Science.gov (United States)

    Jornada, Luciano K; Valvassori, Samira S; Steckert, Amanda V; Moretti, Morgana; Mina, Francielle; Ferreira, Camila L; Arent, Camila O; Dal-Pizzol, Felipe; Quevedo, João

    2011-02-01

    In this study, we assessed the oxidative stress parameters in rats submitted to an animal model of mania induced by ouabain (OUA), which included the use of lithium (Li) and valproate (VPA). Li and VPA treatment reversed and prevented the OUA-induced damage in these structures, however, this effect varies depending on the brain region and treatment regimen. Moreover, the activity of the antioxidant enzymes, namely, superoxide dismutase (SOD) and catalase (CAT) was found to be increased and decreased, respectively, in the brain of OUA-administered rats. Li and VPA modulated SOD and CAT activities in OUA-subjected rats in both experimental models. Our results support the notion that Li and VPA exert antioxidant-like properties in the brain of rats submitted to animal model of mania induced by ouabain.

  4. Selective estrogen receptor-beta (SERM-beta) compounds modulate raphe nuclei tryptophan hydroxylase-1 (TPH-1) mRNA expression and cause antidepressant-like effects in the forced swim test.

    Science.gov (United States)

    Clark, J A; Alves, S; Gundlah, C; Rocha, B; Birzin, E T; Cai, S-J; Flick, R; Hayes, E; Ho, K; Warrier, S; Pai, L; Yudkovitz, J; Fleischer, R; Colwell, L; Li, S; Wilkinson, H; Schaeffer, J; Wilkening, R; Mattingly, E; Hammond, M; Rohrer, S P

    2012-11-01

    Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERβ, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERβ can regulate ERα activity. Moreover, ERβ knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERβ-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERβ in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken

  5. Measurements of Electric Performance and Impedance of a 75 Ah NMC Lithium Battery Module

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard; Engelbrecht, Kurt

    2012-01-01

    Detailed characterization of battery modules is necessary to construct reliable models that incorporate performance related aspects of the modules such as thermodynamics, electrochemical reaction kinetics and degradation mechanisms. Charge-discharge curves, temperature and battery impedance...... measurements can provide information about these aspects. Charge-discharge curves can be used to measure the battery open circuit voltage and the internal resistance. Temperature measurements provide information about the thermodynamic reactions and impedance spectra yield detailed information about...... the reaction kinetics. In this paper we present the measurement methods used to examine the internal resistance, the capacity and the impedance of a 75 Ah NMC battery module. In order to measure the impedance of the battery module and of the individual cells in the module, we combine the single sine technique...

  6. Lithium Chloride Modulates Adipogenesis and Osteogenesis of Human Bone Marrow-Derived Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Linjun Tang

    2015-08-01

    Full Text Available Background/Aims: Lithium chloride (LiCl has long been used as a psychiatric medication; however, its role in the differentiation of bone marrow-derived mesenchymal stem cells (BMSCs remains largely unknown. The aim of this study is to explore the effect of LiCl on the differentiation of BMSCs. Methods: The roles of LiCl in osteogenic and adipogenic processes were observed using alizarin red staining and oil red O staining, respectively. The effects of LiCl on the Wnt and Hedgehog (Hh pathways were investigated. Results: Our data showed that LiCl effectively promoted osteogenesis and inhibited adipogenesis by simultaneously affecting the Wnt and Hh pathways. Conclusion: These results suggest that LiCl influences the differentiation of BMSCs directly through the Wnt and Hh pathways and thus may be a candidate drug for the treatment of osteoporosis.

  7. Passive hybridization of a photovoltaic module with lithium-ion battery cells: A model-based analysis

    Science.gov (United States)

    Joos, Stella; Weißhar, Björn; Bessler, Wolfgang G.

    2017-04-01

    Standard photovoltaic battery systems based on AC or DC architectures require power electronics and controllers, including inverters, MPP tracker, and battery charger. Here we investigate an alternative system design based on the parallel connection of a photovoltaic module with battery cells without any intermediate voltage conversion. This approach, for which we use the term passive hybridization, is based on matching the solar cell's and battery cell's respective current/voltage behavior. A battery with flat discharge characteristics can allow to pin the solar cell to its maximum power point (MPP) independently of the external power consumption. At the same time, upon battery full charge, voltage increase will drive the solar cell towards zero current and therefore self-prevent battery overcharge. We present a modeling and simulation analysis of passively hybridizing a 5 kWp PV system with a 5 kWh LFP/graphite lithium-ion battery. Dynamic simulations with 1-min time resolution are carried out for three exemplary summer and winter days using historic weather data and a synthetic single-family household consumer profile. The results demonstrate the feasibility of the system. The passive hybrid allows for high self-sufficiencies of 84.6% in summer and 25.3% in winter, which are only slightly lower than those of a standard system.

  8. Towards Stable Lithium-Sulfur Batteries with a Low Self-Discharge Rate: Ion Diffusion Modulation and Anode Protection.

    Science.gov (United States)

    Xu, Wen-Tao; Peng, Hong-Jie; Huang, Jia-Qi; Zhao, Chen-Zi; Cheng, Xin-Bing; Zhang, Qiang

    2015-09-01

    The self-discharge of a lithium-sulfur cell decreases the shelf-life of the battery and is one of the bottlenecks that hinders its practical applications. New insights into both the internal chemical reactions in a lithium-sulfur system and effective routes to retard self-discharge for highly stable batteries are crucial for the design of lithium-sulfur cells. Herein, a lithium-sulfur cell with a carbon nanotube/sulfur cathode and lithium-metal anode in lithium bis(trifluoromethanesulfonyl)imide/1,3-dioxolane/dimethyl ether electrolyte was selected as the model system to investigate the self-discharge behavior. Both lithium anode passivation and polysulfide anion diffusion suppression strategies are applied to reduce self-discharge of the lithium-sulfur cell. When the lithium-metal anode is protected by a high density passivation layer induced by LiNO3 , a very low shuttle constant of 0.017 h(-1) is achieved. The diffusion of the polysulfides is retarded by an ion-selective separator, and the shuttle constants decreased. The cell with LiNO3 additive maintained a discharge capacity of 97 % (961 mAh g(-1) ) of the initial capacity after 120 days at open circuit, which was around three times higher than the routine cell (32 % of initial capacity, corresponding to 320 mAh g(-1) ). It is expected that lithium-sulfur batteries with ultralow self-discharge rates may be fabricated through a combination of anode passivation and polysulfide shuttle control, as well as optimization of the lithium-sulfur cell configuration.

  9. Tryptophan-free diet: a new means for rapidly decreasing brain tryptophan content and serotonin synthesis.

    Science.gov (United States)

    Gessa, G L; Biggio, G; Fadda, F; Corsini, G U; Tagliamonte, A

    1975-01-01

    Changes in the synthesis rate of brain serotonin are positively correlated with changes in the concentration of brain tryptophan, indicating that the concentration of tryptophan in the whole brain reflects that at sites of serotonin synthesis. In turn, the concentration of brain tryptophan is positively correlated with that of free serum tryptophan (tryptophan is the only amino acid bound to serum proteins) and negatively to that of other amino acids competing with tryptophan for the same transport from blood to brain. Consistently, experiments in rats have shown that treatments which increase free tryptophan in serum (in respect to competing amino acids) also increase brain tryptophan and serotonin turnover. Conversely, the ingestion of diets containing all amino acids except tryptophan cause a dramatic fall in free serum tryptophan and a parallel decline in brain tryptophan and serotonin synthesis. In man the administration of an amino acid mixture lacking trytophan produces a marked depletion in serum tryptophan concentration.

  10. Thermal-mechanical and thermal-hydraulic integrated study of the Helium-Cooled Lithium Lead Test Blanket Module

    Energy Technology Data Exchange (ETDEWEB)

    Chiovaro, P., E-mail: pg.chiovaro@din.unipa.it [Dipartimento di Ingegneria Nucleare, Universita di Palermo, Palermo (Italy); Di Maio, P.A.; Giammusso, R.; Lupo, Q.; Vella, G. [Dipartimento di Ingegneria Nucleare, Universita di Palermo, Palermo (Italy)

    2010-12-15

    The Helium-Cooled Lithium Lead Test Blanket Module (HCLL-TBM) is one of the two TBM to be installed in an ITER equatorial port since day 1 of operation, with the specific aim to investigate the main concept functionalities and issues such as high efficiency helium cooling, resistance to thermo-mechanical stresses, manufacturing techniques, as well as tritium transport, magneto-hydrodynamics effects and corrosion. In particular, in order to show a DEMO-relevant thermo-mechanical and thermal-hydraulic behavior, the HCLL-TBM has to meet several requirements especially as far as its coolant thermofluid-dynamic conditions and its thermal-mechanical field are concerned. The present paper is focused on the assessment of the HCLL-TBM thermal-mechanical performances under both nominal and accidental load conditions, by adopting a computational approach based on the Finite Element Method. A realistic 3D finite element model of the whole HCLL-TBM, in the horizontal first wall design has been set up, consisting of about 597,000 elements and 767,000 nodes. In particular, since the thermal fields of both the module and the coolant are strictly coupled, the helium flow domain has been modeled too and a thermal contact model has been set up to properly simulate the convective heat transfer between the structure wall and the coolant. Pure conductive heat transfer has been assumed within the Pb-Li eutectic alloy of the breeder units. The volumetric density of the nuclear deposited power, recently calculated at Department of Nuclear Engineering of the University of Palermo by the MCNP 4C code, has been applied as distributed thermal load in order to assess the potential influence on the module thermo-mechanical performances of the markedly non-uniform poloidal and toroidal distributions that have been predicted within the Segment Box. Different loading scenarios have been considered as to the heat flux onto the module First Wall. Steady state and transient thermal-mechanical analyses

  11. L-tryptophan in depression.

    Science.gov (United States)

    Farkas, T; Dunner, D L; Fieve, R R

    1976-06-01

    L-tryptophan, the amino acid precursor of serotonin, was administered to 16 depressive patients in a double-blind study of its potential antidepressant efficacy. Antidepressant responses were observed in one of ten unipolar patients and in three of six bipolar patients. These results are discussed in the context of possible interactions of amines with electrolyte systems in the etiology of affective illness.

  12. Analysis of the thermo-mechanical behaviour of the DEMO Water-Cooled Lithium Lead breeding blanket module under normal operation steady state conditions

    Energy Technology Data Exchange (ETDEWEB)

    Di Maio, P.A.; Arena, P. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Aubert, J. [CEA Saclay, DEN/DANS/DM2S/SEMT, 91191 Gif sur Yvette Cedex (France); Bongiovì, G. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Chiovaro, P., E-mail: pierluigi.chiovaro@unipa.it [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Giammusso, R. [ENEA – C.R. Brasimone, 40032 Camugnano (Italy); Li Puma, A. [CEA Saclay, DEN/DANS/DM2S/SEMT, 91191 Gif sur Yvette Cedex (France); Tincani, A. [ENEA – C.R. Brasimone, 40032 Camugnano (Italy)

    2015-10-15

    Highlights: • A DEMO WCLL blanket module thermo-mechanical behaviour has been investigated. • Two models of the WCLL blanket module have been set-up adopting a code based on FEM. • The water flow domain in the module has been considered. • A set of uncoupled steady state thermo-mechanical analyses has been carried out. • Critical temperature is not overcome. Safety verifications are generally satisfied. - Abstract: Within the framework of DEMO R&D activities, a research cooperation has been launched between ENEA, the University of Palermo and CEA to investigate the thermo-mechanical behaviour of the outboard equatorial module of the DEMO1 Water-Cooled Lithium Lead (WCLL) blanket under normal operation steady state scenario. The research campaign has been carried out following a theoretical–computational approach based on the Finite Element Method (FEM) and adopting a qualified commercial FEM code. In particular, two different 3D FEM models (Model 1 and Model 2), reproducing respectively the central and the lateral poloidal–radial slices of the WCLL blanket module, have been set up. A particular attention has been paid to the modelling of water flow domain, within both the segment box channels and the breeder zone tubes, to simulate realistically the coolant-box thermal coupling. Results obtained are herewith reported and critically discussed.

  13. Tryptophan and tyrosine catabolic pattern in neuropsychiatric disorders.

    Science.gov (United States)

    Ravikumar, A; Deepadevi, K V; Arun, P; Manojkumar, V; Kurup, P A

    2000-09-01

    Catabolism of tryptophan and tyrosine in relation to the isoprenoid pathway was studied in neurological and psychiatric disorders. The concentration of trytophan, quinolinic acid, kynurenic acid, serotonin and 5-hydroxyindoleacetic acid was found to be higher in the plasma of patients with all these disorders; while that of tyrosine, dopamine, epinephrine and norepinephrine was lower. There was increase in free fatty acids and decrease in albumin (factors modulating tryptophan transport) in the plasma of these patients. Concentration of digoxin, a modulator of amino acid transport, and the activity of HMG CoA reductase, which synthesizes digoxin, were higher in these patients; while RBC membrane Na+-K+ ATPase activity showed a decrease. Concentration of plasma ubiquinone (part of which is synthesised from tyrosine) and magnesium was also lower in these patients. No morphine could be detected in the plasma of these patients except in MS. On the other hand, strychnine and nicotine were detectable. These results indicate hypercatabolism of tryptophan and hypocatabolism of tyrosine in these disorders, which could be a consequence of the modulating effect of hypothalamic digoxin on amino acid transport.

  14. Tryptophan and tyrosine catabolic pattern in neuropsychiatric disorders.

    Directory of Open Access Journals (Sweden)

    Ravikumar A

    2000-07-01

    Full Text Available Catabolism of tryptophan and tyrosine in relation to the isoprenoid pathway was studied in neurological and psychiatric disorders. The concentration of trytophan, quinolinic acid, kynurenic acid, serotonin and 5-hydroxyindoleacetic acid was found to be higher in the plasma of patients with all these disorders; while that of tyrosine, dopamine, epinephrine and norepinephrine was lower. There was increase in free fatty acids and decrease in albumin (factors modulating tryptophan transport in the plasma of these patients. Concentration of digoxin, a modulator of amino acid transport, and the activity of HMG CoA reductase, which synthesizes digoxin, were higher in these patients; while RBC membrane Na+-K+ ATPase activity showed a decrease. Concentration of plasma ubiquinone (part of which is synthesised from tyrosine and magnesium was also lower in these patients. No morphine could be detected in the plasma of these patients except in MS. On the other hand, strychnine and nicotine were detectable. These results indicate hypercatabolism of tryptophan and hypocatabolism of tyrosine in these disorders, which could be a consequence of the modulating effect of hypothalamic digoxin on amino acid transport.

  15. Structural modulation of lithium metal-electrolyte interface with three-dimensional metallic interlayer for high-performance lithium metal batteries

    Science.gov (United States)

    Lee, Hongkyung; Song, Jongchan; Kim, Yun-Jung; Park, Jung-Ki; Kim, Hee-Tak

    2016-08-01

    The use of lithium (Li) metal anodes has been reconsidered because of the necessity for a higher energy density in secondary batteries. However, Li metal anodes suffer from ‘dead’ Li formation and surface deactivation which consequently form a porous layer of redundant Li aggregates. In this work, a fibrous metal felt (FMF) as a three-dimensional conductive interlayer was introduced between the separator and the Li metal anode to improve the reversibility of the Li metal anode. The FMF can facilitate charge transfer in the porous layer, rendering it electrochemically more active. In addition, the FMF acted as a robust scaffold to accommodate Li deposits compactly in its interstitial sites. The FMF-integrated Li metal (FMF/Li) electrode operated with a small polarisation even at a current density of 10 mA cm-2, and it exhibited a seven times longer cycle-life than that of an FMF-free Li electrode in a symmetric cell configuration. A Li metal battery (LMB) using the FMF/Li electrode and a LiFePO4 electrode exhibited a two-fold increase in cycling stability compared with that of a bare Li metal electrode, demonstrating the practical effectiveness of this approach for high performance LMBs.

  16. Parallel variation of ventricular CSF tryptophan and free serum tryptophan in man.

    Science.gov (United States)

    Young, S N; Lal, S; Feldmuller, F; Sourkes, T L; Ford, R M; Kiely, M; Martin, J B

    1976-01-01

    Tryptophan was measured in the ventricular CSE and serum and the neutral amino acids leucine, isoleucine, valine, phenylalanine, and tyrosine were measured in the serum of two cases with ventricular drains. Samples were taken every two hours for 24 hours in one case and for 16 hours in the other. The CSF tryptophan was correlated significantly with the free--that is, non-albumin-bound--serum tryptophan but not with the total serum tryptophan. CSF tryptophan was not correlated significantly with the ratio of free serum tryptophan to the sum of the neutral amino acids. These data suggest that, in man, brain tryptophan concentrations are influenced by the free and not the total serum tryptophan and that physiological variations of the neutral amino acids do not appreciably influence the concentration of brain trytophan.

  17. l-Tryptophan Production by Achromobacter liquidum

    Science.gov (United States)

    Ujimaru, Toshihiko; Kakimoto, Toshio; Chibata, Ichiro

    1983-01-01

    Conditions for the production of tryptophanase from Achromobacter liquidum and for the conversion of l-serine and indole to l-tryptophan were studied. The enzyme could be produced in amounts as great as 0.750 U/ml (degradation) and 0.294 U/ml (synthesis) by shaking cultures at 30°C in a medium containing dextrin, yeast extract, l-tryptophan, and l-glutamic acid. l-Tryptophan was produced most efficiently by shaking the cells at 37°C in a reaction mixture containing 60 mg of l-serine per ml, 60 mg of indole per ml, and 0.5 mM pyridoxal phosphate. After 3 days, 96 mg of l-tryptophan per ml was formed, and l-tryptophan was easily isolated to 85.4% yield by concentration of the reaction mixture. PMID:16346331

  18. Posttranslational isoprenylation of tryptophan in bacteria

    Science.gov (United States)

    Sugita, Tomotoshi; Abe, Ikuro

    2017-01-01

    Posttranslational isoprenylation is generally recognized as a universal modification of the cysteine residues in peptides and the thiol groups of proteins in eukaryotes. In contrast, the Bacillus quorum sensing peptide pheromone, the ComX pheromone, possesses a posttranslationally modified tryptophan residue, and the tryptophan residue is isoprenylated with either a geranyl or farnesyl group at the gamma position to form a tricyclic skeleton that bears a newly formed pyrrolidine, similar to proline. The post-translational dimethylallylation of two tryptophan residues of a cyclic peptide, kawaguchipeptin A, from cyanobacteria has also been reported. Interestingly, the modified tryptophan residues of kawaguchipeptin A have the same scaffold as that of the ComX pheromones, but with the opposite stereochemistry. This review highlights the biosynthetic pathways and posttranslational isoprenylation of tryptophan. In particular, recent studies on peptide modifying enzymes are discussed.

  19. Lithium Intoxication

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2011-09-01

    Full Text Available Lithium has been commonly used for the treatment of several mood disorders particularly bipolar disorder in the last 60 years. Increased intake and decreased excretion of lithium are the main causes for the development of lithium intoxication. The influence of lithium intoxication on body is evaluated as two different groups; reversible or irreversible. Irreversible damage is usually related with the length of time passed as intoxicated. Acute lithium intoxication could occur when an overdose of lithium is received mistakenly or for the purpose of suicide. Patients may sometimes take an overdose of lithium for self-medication resulting in acute intoxication during chronic, while others could develop chronic lithium intoxication during a steady dose treatment due to a problem in excretion of drug. In such situations, it is crucial to be aware of risk factors, to recognize early clinical symptoms and to conduct a proper medical monitoring. In order to justify or exclude the diagnosis, quantitative evaluation of lithium in blood and toxicologic screening is necessary. Following the monitoring schedules strictly and urgent intervention in case of intoxication would definitely reduce mortality and sequela related with lithium intoxication. In this article, the etiology, frequency, definition, clinical features and treatment approaches to the lithium intoxication have been briefly reviewed.

  20. Review of the implications of dietary tryptophan intake in patients with irritable bowel syndrome and psychiatric disorders.

    Science.gov (United States)

    Agazzi, A; De Ponti, F; De Giorgio, R; Candura, S M; Anselmi, L; Cervio, E; Di Nucci, A; Tonini, M

    2003-08-01

    In this review, we address the possible role of the essential amino acid L-tryptophan or its metabolic derivative 5-hydroxytryptophan in the modulation of serotonin (5-hydroxytryptamine) synthesis and thereby in affecting the pathophysiology of central and peripheral nervous system disorders, including depression and irritable bowel syndrome. L-Tryptophan may represent a link between apparently disparate functional disorders and is of interest for general gastroenterologists, neurogastroenterologists, and neurologists. On the basis of estimates showing that approximately 20% of patients with functional bowel disorders seeking care in referral centres have psychiatric comorbidity, we attempt to provide a conceptual framework for defining the possible role of L-tryptophan in this population.

  1. Hydrogen, lithium, and lithium hydride production

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Sam W.; Spencer, Larry S.; Phillips, Michael R.; Powell, G. Louis; Campbell, Peggy J.

    2017-06-20

    A method is provided for extracting hydrogen from lithium hydride. The method includes (a) heating lithium hydride to form liquid-phase lithium hydride; (b) extracting hydrogen from the liquid-phase lithium hydride, leaving residual liquid-phase lithium metal; (c) hydriding the residual liquid-phase lithium metal to form refined lithium hydride; and repeating steps (a) and (b) on the refined lithium hydride.

  2. Hydrogen, lithium, and lithium hydride production

    Science.gov (United States)

    Brown, Sam W; Spencer, Larry S; Phillips, Michael R; Powell, G. Louis; Campbell, Peggy J

    2014-03-25

    A method of producing high purity lithium metal is provided, where gaseous-phase lithium metal is extracted from lithium hydride and condensed to form solid high purity lithium metal. The high purity lithium metal may be hydrided to provide high purity lithium hydride.

  3. Lithium Poisoning

    DEFF Research Database (Denmark)

    Baird-Gunning, Jonathan; Lea-Henry, Tom; Hoegberg, Lotte C G

    2017-01-01

    is required. The cause of lithium poisoning influences treatment and 3 patterns are described: acute, acute-on-chronic, and chronic. Chronic poisoning is the most common etiology, is usually unintentional, and results from lithium intake exceeding elimination. This is most commonly due to impaired kidney...... function caused by volume depletion from lithium-induced nephrogenic diabetes insipidus or intercurrent illnesses and is also drug-induced. Lithium poisoning can affect multiple organs; however, the primary site of toxicity is the central nervous system and clinical manifestations vary from asymptomatic...... supratherapeutic drug concentrations to clinical toxicity such as confusion, ataxia, or seizures. Lithium poisoning has a low mortality rate; however, chronic lithium poisoning can require a prolonged hospital length of stay from impaired mobility and cognition and associated nosocomial complications. Persistent...

  4. Structural Characterization of New Microcystins Containing Tryptophan and Oxidized Tryptophan Residues

    Directory of Open Access Journals (Sweden)

    David P. Hamilton

    2013-08-01

    Full Text Available Microcystins are cyclic peptides produced by cyanobacteria, which can be harmful to humans and animals when ingested. Eight of the (more than 90 microcystin variants presently characterized, contain the amino acid tryptophan. The well-researched oxidation products of tryptophan; kynurenine, oxindolylalanine, and N-formylkynurenine, have been previously identified in intact polypeptides but microcystin congeners containing oxidized tryptophan moieties have not been reported. Liquid chromatography-tandem mass spectrometric analysis of an extract of Microcystis CAWBG11 led to the tentative identification of two new tryptophan-containing microcystins (MC‑WAba and MC-WL, as well as eight other microcystin analogs containing kynurenine, oxindolylalanine and N‑formylkynurenine (Nfk. Investigation of one of these congeners (MC‑NfkA by nuclear magnetic resonance spectroscopy was used to verify the presence of Nfk in the microcystin. Liquid chromatography-mass spectrometry analysis of a tryptophan oxidation experiment demonstrated that tryptophan-containing microcystins could be converted into oxidized tryptophan analogs and that low levels of oxidized tryptophan congeners were present intracellularly in CAWBG11. MC-NfkR and MC-LNfk were detected in standards of MC-WR and MC-LW, indicating that care during storage of tryptophan-containing microcystins is required.

  5. Two-dimensional cross-section sensitivity and uncertainty analysis of the LBM (Lithium Blanket Module) experiments at LOTUS

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, J.W.; Dudziak, D.J.; Pelloni, S.; Stepanek, J.

    1988-01-01

    In a recent common Los Alamos/PSI effort, a sensitivity and nuclear data uncertainty path for the modular code system AARE (Advanced Analysis for Reactor Engineering) was developed. This path includes the cross-section code TRAMIX, the one-dimensional finite difference S/sub N/-transport code ONEDANT, the two-dimensional finite element S/sub N/-transport code TRISM, and the one- and two-dimensional sensitivity and nuclear data uncertainty code SENSIBL. Within the framework of the present work a complete set of forward and adjoint two-dimensional TRISM calculations were performed both for the bare, as well as for the Pb- and Be-preceeded, LBM using MATXS8 libraries. Then a two-dimensional sensitivity and uncertainty analysis for all cases was performed. The goal of this analysis was the determination of the uncertainties of a calculated tritium production per source neutron from lithium along the central Li/sub 2/O rod in the LBM. Considered were the contributions from /sup 1/H, /sup 6/Li, /sup 7/Li, /sup 9/Be, /sup nat/C, /sup 14/N, /sup 16/O, /sup 23/Na, /sup 27/Al, /sup nat/Si, /sup nat/Cr, /sup nat/Fe, /sup nat/Ni, and /sup nat/Pb. 22 refs., 1 fig., 3 tabs.

  6. Surface plasmon polariton excitation by electrostatic modulation and phase grating in indium-tin-oxide coated lithium niobate slabs

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hao; Zhang, Jingwen; Zhao, Hua, E-mail: zhaohuaz@hit.edu.cn [Institute of Modern Optics, Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Key Laboratory of Micro-Optics and Photonics Technology of Heilongjiang Province, Harbin 150001 (China)

    2015-08-14

    Excitation of surface plasmon polaritons (SPPs) in a non-metal system in visible regime is discussed. With the assistance of phase grating resulted from photorefractive effect and electrostatic modulation of ITO induced by strong photovoltaic effect in iron-doped LiNbO{sub 3}, phase matching condition could be satisfied for SPP excitation in this semiconductor/dielectric system. Both the phase grating instead of metal grating and electrostatic modulation of semiconductor could be used for the design of tunable plasmonic devices based on nonlinear photorefractive crystals.

  7. Femtosecond writing of near-surface waveguides in lithium niobate for low-loss electro-optical modulators of broadband emission

    Science.gov (United States)

    Bukharin, Mikhail A.; Skryabin, Nikolay N.; Khudyakov, Dmitriy V.; Vartapetov, Sergey K.

    2016-05-01

    In the investigation we demonstrated technique of direct femtosecond laser writing of tracks with induced refractive index at record low depth under surface of lithium niobate (3-15 μm). It was shown that with the help of proposed technique one can be written claddings of near surface optical waveguides that plays a key role in fabrication of fast electro-optical modulators with low operating voltage. Fundamental problem resolved in the investigation consists in suppression of negative factors impeding femtosecond inscription of waveguides at low depths. To prevent optical breakdown of crystal surface we used high numerical aperture objectives for focusing of light. It was shown, that advanced heat accumulation regime of femtosecond inscription is inapplicable for writing of near-surface waveguides, and near the surface waveguides should be written in non-thermal regime in contrast to widespread femtosecond writing at depths of tens micrometers. Inscribed waveguides were examined for optical losses and polarization properties. It was experimentally shown, that femtosecond written near surface waveguides have such advantages over widely used proton exchanged and Ti-diffusion waveguides as lower optical losses (down to 0.3 dB/cm) and maintaining of all polarization states of propagation light, which is crucial for development of electro-optical modulators for broadband and ultrashort laser emission. Novelty of the results consists in technique of femtosecond inscription of waveguides at record low depths under the surface of crystals. As compared to previous investigations in the field (structures at depths near 50 um with buried electrodes), the obtained waveguides could be used with simple closely adjacent on-surface electrodes.

  8. Lithium nephrotoxicity.

    Science.gov (United States)

    Oliveira, Jobson Lopes de; Silva Júnior, Geraldo Bezerra da; Abreu, Krasnalhia Lívia Soares de; Rocha, Natália de Albuquerque; Franco, Luiz Fernando Leonavicius G; Araújo, Sônia Maria Holanda Almeida; Daher, Elizabeth de Francesco

    2010-01-01

    Lithium has been widely used in the treatment of bipolar disorder. Its renal toxicity includes impaired urinary concentrating ability and natriuresis, renal tubular acidosis, tubulointerstitial nephritis progressing to chronic kidney disease and hypercalcemia. The most common adverse effect is nephrogenic diabetes insipidus, which affects 20-40% of patients within weeks of lithium initiation. Chronic nephropathy correlates with duration of lithium therapy. Early detection of renal dysfunction should be achieved by rigorous monitoring of patients and close collaboration between psychiatrists and nephrologists. Recent experimental and clinical studies begin to clarify the mechanisms by which lithium induces changes in renal function. The aim of this study was to review the pathogenesis, clinical presentation, histopathological aspects and treatment of lithium-induced nephrotoxicity.

  9. [Lithium nephropathy].

    Science.gov (United States)

    Kaczmarczyk, Ireneusz; Sułowicz, Władysław

    2013-01-01

    Lithium salts are the first-line drug therapy in the treatment of uni- and bipolar disorder since the sixties of the twentieth century. In the mid-70s, the first information about their nephrotoxicity appeared. Lithium salts have a narrow therapeutic index. Side effects during treatment are polyuria, polydipsia and nephrogenic diabetes insipidus. Accidental intoxication can cause acute renal failure requiring renal replacement therapy while receiving long-term lithium salt can lead to the development of chronic kidney disease. The renal biopsy changes revealed a type of chronic tubulointerstitial nephropathy. The imaging studies revealed the presence of numerous symmetric microcysts. Care of the patient receiving lithium should include regular determination of serum creatinine, creatinine clearance and monitoring of urine volume. In case of deterioration of renal function reducing the dose should be considered.

  10. Rotational Spectra of Phenylalanine, Tirosine and Tryptophan

    Science.gov (United States)

    Mata, S.; Perez, C.; Sanz, M. E.; Blanco, S.; López, J. C.; Alonso, J. L.

    2009-06-01

    The rotational spectra of the aromatic natural amino acids phenylalanine, tyrosine and tryptophan have been investigated by Laser Ablation Molecular Beam Fourier transform Microwave Spectroscopy LA-MB-FTMW. The spectra of two rotamers of phenylalanine have been detected in the supersonic expansion. Both forms are stabilized by a chain of intramolecular hydrogen bonds O-H\\cdotsN-H\\cdots{π}, being the carboxylic group incis configuration. One conformer of tyrosine, which only differs from phenylalanine in a -OH group inpara position, has been also characterized. Preliminary results on the rotational spectrum of tryptophan are presented.

  11. Tryptophan distribution in yeast hexokinase isoenzyme B

    Energy Technology Data Exchange (ETDEWEB)

    Kramp, D.C.; Feldman, I.

    1978-01-01

    Titrations of the quenching of the tryptophan fluorescence of yeast hexokinase isoenzyme B by Cs/sup +/, I/sup -/ and glucose as quenchers, singly and in various combinations, have been performed at pH 5.5, 8.3, and 10.1 at 20/sup 0/C. The iodide and glucose titrations at pH 8.3 indicated that the four tryptophan residues of the monomer subunit can be classified as: (1) a highly accessible surface tryptophan (Trp-S/sub 1/); (2) a surface tryptophan (Trp-S/sub 2/) with restricted accessibility (possibly in a crevice); (3) a glucose-quenchable cleft tryptophan (Trp-G); and (4) a buried tryptophan (Trp-B) in the hydrophobic interior. The Stern-Volmer constants, k/sub I/, calculated for iodide quenching of the two surface residues at pH 8.3 are 22 and 3.3 M/sup -1/. The k/sub I/ value of Trp-G at this pH is iodide dependent, increasing from 1.2 to 1.4 M/sup -1/ as the iodide concentration increases from 0.1 to 0.65 M, probably because of iodide-induced alteration of the cleft structure. An iodide concentration above 0.65 M quenches Trp-B detectably, demonstrating that a high iodide concentration produces a large structural change in the isoenzyme. The percentages of the total 350 nm emission attributable to the individual tryptophan residues at pH 8.3 are 9, 22, 28, and 41%, for Trp-S/sub 1/, Trp-S/sub 2/, Trp-G, and Trp-B, respectively. At pH 5.5 even a low iodide concentration causes some quenching of Trp-B, especially in presence of saturating glucose. Glucose increases the iodide quenchability at this pH. At pH 10.1 glucose does not quench the tryptophan emission, and it does not influence the iodide-quenching action. However, at this high pH the k/sub 1/ of Trp-S/sub 1/ is reduced to the point where it is not resolvable from the k/sub I/ values of Trp-S/sub 2/ and Trp-G, even though the sum of the fractional fluorescence contributions of these three residues is the same as at pH 8.3.

  12. Improving therapeutics in anorexia nervosa with tryptophan.

    Science.gov (United States)

    Haleem, Darakhshan Jabeen

    2017-06-01

    A growing body of evidence suggests that our diet is an important contributing factor in the development, management and prevention of a number of psychiatric illnesses. Tryptophan, an essential amino acid, is the sole precursor of neurotransmitter 5-hydroxytryptamine (5-HT; serotonin). Administration of tryptophan can boost serotonin neurotransmission to produce therapeutically important effects in serotonin deficiency disorders. Anorexia nervosa (AN) an eating disorder associated with high levels of psychiatric comorbidity including psychosis, hyperactivity, depression and anxiety has highest lethality of all psychiatric illnesses. Evidence suggests that excessive dieting and food restriction can decrease brain tryptophan and serotonin in AN patients to precipitate depression, psychosis and hyperactivity. There are currently no FDA approved pharmacological treatments available for AN patients; antidepressants and antipsychotics, largely used to treat associated psychiatric comorbidities are also not very effective. The aim of this non-systematic review article is to evaluate and document a potential importance of tryptophan supplementation in improving therapeutics in AN patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Tryptophan-induced eosinophilia-myalgia syndrome.

    OpenAIRE

    Criswell, L A; Sack, K. E.

    1990-01-01

    Eight patients who became ill while taking tryptophan had myalgia, fatigue, rash, fever, edema, alopecia, arthralgias, diminished joint motion, skin tightening, muscle cramping, and distal paresthesias. Three had shortness of breath, and one had pulmonary hypertension. Laboratory abnormalities included peripheral eosinophilia, leukocytosis, thrombocytosis, raised erythrocyte sedimentation rate, and elevated serum levels of aldolase, lactate dehydrogenase, and liver enzymes. Of 4 chest radiogr...

  14. Origin of tryptophan fluorescence lifetimes. Part 2: fluorescence lifetimes origin of tryptophan in proteins.

    Science.gov (United States)

    Albani, J R

    2014-01-01

    Fluorescence intensity decays of L-tryptophan in proteins dissolved in pH 7 buffer, in ethanol and in 6 M guanidine pH 7.8 and in lyophilized proteins were measured. In all protein conditions, three lifetimes were obtained along the emission spectrum (310-410 nm). The two shortest lifetimes are in the same range of those obtained for L-Trp in water or in ethanol. Thus, these two lifetimes originate from specific two sub-structures existing in the excited state and are inherent to the tryptophan structure independently of the surrounding environment (amino acids residues, solvent, etc.) In proteins, the third lifetime originates from the interactions that are occurring between tryptophan residues and neighboring amino acids. Populations of these lifetimes are independent of the excitation wavelength and thus originate from pre-defined sub structures existing in the excited state and put into evidence after tryptophan excitation. Fluorescence decay studies of different tripeptides having a tryptophan residue in second position show that the best analysis is obtained with two fluorescence lifetimes. Consequently, this result seems to exclude the possibility that peptide bond induces the third fluorescence lifetimes. Indole dissolved in water and/or in ethanol emits with two fluorescence lifetimes that are completely different from those observed for L-Trp. Absence of the third lifetime in ethanol demonstrates that indole behaves differently when compared to tryptophan. Thus, it seems not adequate to attribute fluorescence lifetime or fluorescence properties of tryptophan to indole ring and to compare tryptophan fluorescence properties in proteins to molecules having close structures such as NATA which fluoresces with one lifetime.

  15. Origin of tryptophan fluorescence lifetimes part 1. Fluorescence lifetimes origin of tryptophan free in solution.

    Science.gov (United States)

    Albani, J R

    2014-01-01

    Fluorescence intensity decays of L-tryptophan free in polar, hydrophobic and mixture of polar-hydrophobic solvents were recorded along the emission spectrum (310-410 nm). Analysis of the data show that emission of tryptophan occurs with two lifetimes in 100% polar and hydrophobic environments. The values of the two lifetimes are not the same in both environments while their populations (pre-exponentials values) are identical. Fluorescence lifetimes and pre-exponentials values do not change with the excitation wavelength and thus are independent of excitation energy. Our results indicate that tryptophan emission occurs from two specific sub-structures existing in the excited state. These sub-structures differ from those present in the ground states and characterize an internal property and/or organization of the tryptophan structure in the excited state. By sub-substructure, we mean here tryptophan backbone and its electronic cloud. In ethanol, three fluorescence lifetimes were measured; two lifetimes are very close to those observed in water (0.4-0.5 ns and 2-4 ns). Presence of a third lifetime for tryptophan in ethanol results from the interaction of both hydrophobic and hydrophilic dipoles or chemical functions of ethanol with the fluorophore.

  16. Navy Lithium Battery Safety

    Science.gov (United States)

    2010-07-14

    lithium -sulfur dioxide (Li-SO2), lithium - thionyl chloride (Li- SOCL2), and lithium -sulfuryl chloride (Li-S02CL2...and 1980’s with active primary cells: Lithium -sulfur dioxide (Li-SO2) Lithium - thionyl chloride (Li-SOCL2) Lithium -sulfuryl chloride (Li-S0 CL ) 2 2...DISTRIBUTION A. Approved for public release; distribution unlimited. NAVY LITHIUM BATTERY SAFETY John Dow1 and Chris Batchelor2 Naval

  17. Effect of Tryptophan on the corrosion behavior of low alloy steel in sulfamic acid

    OpenAIRE

    Hesham T.M. Abdel-Fatah; Salah A.M. Rashwan; S.M. Abd El Wahaab; Aliaa A.M. Hassan

    2016-01-01

    Sulfamic acid is widely used in various industrial acid cleaning applications. In the present work, the inhibition effect of Tryptophan (Tryp) on the corrosion of low alloy steel in sulfamic acid solutions at four different temperatures was studied. The investigations involved electrochemical methods (electrochemical impedance spectroscopy; EIS and the new technique electrochemical frequency modulation; EFM) as well as gravimetric measurements. The inhibition efficiency and the apparent activ...

  18. Vitis labrusca extract effects on cellular dynamics and redox modulations in a SH-SY5Y neuronal cell model: a similar role to lithium.

    Science.gov (United States)

    Scola, Gustavo; Laliberte, Victoria Louise Marina; Kim, Helena Kyunghee; Pinguelo, Arsene; Salvador, Mirian; Young, L Trevor; Andreazza, Ana Cristina

    2014-12-01

    Oxidative stress and calcium imbalance are consistently reported in bipolar disorder (BD). Polymorphism of voltage-dependent calcium channel, L type, alpha 1C subunit (CACNA1c), which is responsible for the regulation of calcium influx, was also shown to have a strong association with BD. These alterations can lead to a number of different consequences in the cell including production of reactive species causing oxidative damage to proteins, lipids and DNA. Lithium is the most frequent medication used for the treatment of BD. Despite lithium's effects, long-term use can result in many negative side effects. Therefore, there is an urgent need for the development of drugs that may have similar biological effects as lithium without the negative consequences. Moreover, polyphenols are secondary metabolites of plants that present multi-faceted molecular abilities, such as regulation of cellular responses. Vitis labrusca extract (VLE), a complex mixture of polyphenols obtained from seeds of winery wastes of V. labrusca, was previously characterized by our group. This extract presented powerful antioxidant and neuroprotective properties. Therefore, the ability of VLE to ameliorate the consequences of hydrogen peroxide (H2O2)-induced redox alterations to cell viability, intracellular calcium levels and the relative levels of the calcium channel CACNA1c in comparison to lithium's effects were evaluated using a neuroblastoma cell model. H2O2 treatment increased cell mortality through apoptotic and necrotic pathways leading to an increase in intracellular calcium levels and alterations to relative CACNA1c levels. VLE and lithium were found to similarly ameliorate cell mortality through regulation of the apoptotic/necrotic pathways, decreasing intracellular calcium levels and preventing alterations to the relative levels of CACNA1c. The findings of this study suggest that VLE exhibits protective properties against oxidative stress-induced alterations similar to that of lithium

  19. Evaluation of acute tryptophan depletion and sham depletion with a gelatin-based collagen peptide protein mixture

    DEFF Research Database (Denmark)

    Stenbæk, D S; Einarsdottir, H S; Goregliad-Fjaellingsdal, T

    2016-01-01

    Acute Tryptophan Depletion (ATD) is a dietary method used to modulate central 5-HT to study the effects of temporarily reduced 5-HT synthesis. The aim of this study is to evaluate a novel method of ATD using a gelatin-based collagen peptide (CP) mixture. We administered CP-Trp or CP+Trp mixtures...

  20. Purification and Characterization of Tryptophan Hydroxylase

    DEFF Research Database (Denmark)

    Haahr, Lærke Tvedebrink

    This thesis deals with the purification and characterization of the iron-containing enzyme tryptophan hydroxylase (TPH). TPH exists in two isoforms, called TPH1 and TPH2. Each isoform consists of threestructural distinct domains: the regulatory, the catalytic and the tetramerization domain. TPH...... of this project was to developpurification methods for full-length TPH1 and TPH2 as well as to characterize purified TPH variants. A successful purification method for full-length human TPH1 (hTPH1) was developed, which resulted in pure, active and stable protein. The method includes affinity-purification using....... The crystallization procedure for the catalytic domain of gallus gallus TPH1 (cgTPH1) was optimized to faster crystal growth by addition of tryptophan and incubation at room temperature. Crystals without imidazole in the crystallization conditions could be obtained. The solved structures were however of poor quality...

  1. Synthesis of constrained analogues of tryptophan

    Directory of Open Access Journals (Sweden)

    Elisabetta Rossi

    2015-10-01

    Full Text Available A Lewis acid-catalysed diastereoselective [4 + 2] cycloaddition of vinylindoles and methyl 2-acetamidoacrylate, leading to methyl 3-acetamido-1,2,3,4-tetrahydrocarbazole-3-carboxylate derivatives, is described. Treatment of the obtained cycloadducts under hydrolytic conditions results in the preparation of a small library of compounds bearing the free amino acid function at C-3 and pertaining to the class of constrained tryptophan analogues.

  2. Lithium in 2012

    Science.gov (United States)

    Jaskula, B.W.

    2013-01-01

    In 2012, estimated world lithium consumption was about 28 kt (31,000 st) of lithium contained in minerals and compounds, an 8 percent increase from that of 2011. Estimated U.S. consumption was about 2 kt (2,200 st) of contained lithium, the same as that of 2011. The United States was thought to rank fourth in consumption of lithium and remained the leading importer of lithium carbonate and the leading producer of value-added lithium materials. One company, Rockwood Lithium Inc., produced lithium compounds from domestic brine resources near Silver Peak, NV.

  3. Acute tryptophan depletion attenuates brain-heart coupling following external feedback

    Directory of Open Access Journals (Sweden)

    Erik M Mueller

    2012-04-01

    Full Text Available External and internal performance feedback triggers neural and visceral modulations such as reactions in the medial prefrontal cortex and insulae or changes of heart period (HP. The functional coupling of neural and cardiac responses following feedback (cortico-cardiac connectivity is not well understood. While linear time-lagged within-subjects correlations of single-trial EEG and HP (cardio-electroencephalographic covariance-tracing, CECT indicate a robust negative coupling of EEG magnitude 300 ms after presentation of an external feedback stimulus with subsequent alterations of heart period (the so-called N300H phenomenon, the neurotransmitter systems underlying feedback-evoked cortico-cardiac connectivity are largely unknown. Because it has been shown that acute tryptophan depletion (ATD, attenuating brain serotonin (5-HT, decreases cardiac but not neural correlates of feedback processing, we hypothesized that 5-HT may be involved in feedback-evoked cortico-cardiac connectivity. In a placebo-controlled double-blind crossover design, twelve healthy participants received a tryptophan-free amino-acid drink at one session and a balanced amino-acid control-drink on another and twice performed a time-estimation task with feedback presented after each trial. N300H magnitude and plasma tryptophan levels were assessed. Results indicated a robust N300H after the control drink, which was significantly attenuated following ATD. Moreover, plasma tryptophan levels during the control session were correlated with N300H amplitude such that individuals with lower tryptophan levels showed reduced N300H. Together, these findings indicate that 5-HT is important for feedback-induced covariation of cortical and cardiac activity. Because individual differences in anxiety have previously been linked to 5-HT, cortico-cardiac coupling and feedback processing, the present findings may be particularly relevant for futures studies linking 5-HT to anxiety.

  4. Dietary tryptophan intake and suicide rate in industrialized nations.

    Science.gov (United States)

    Voracek, Martin; Tran, Ulrich S

    2007-03-01

    The objective of this study was to assess the ecological association of dietary tryptophan intake and suicide rates across industrialized nations. Tryptophan, an essential amino acid, is the rate-limiting precursor of serotonin biosynthesis. The serotonergic system has been strongly implicated in the neurobiology of suicide. Contemporary male and female suicide rates for the general population (42 countries) and the elderly (38 countries) were correlated with national estimates of dietary tryptophan intake. Measures of tryptophan intake were significantly negatively associated to national suicide rates. Controlling for national affluence, total alcohol consumption and happiness levels slightly attenuated these associations, but left all of them negative. The effect is an ecological (group-level) finding. Estimated per capita tryptophan supply is only a proxy for actual consumption. Developed nations ranking high in dietary tryptophan intake rank low in suicide rates, independent of national wealth, alcohol intake and happiness.

  5. Tryptophan and kynurenine determination in human hair by liquid chromatography.

    Science.gov (United States)

    Dario, Michelli F; Freire, Thamires Batello; Pinto, Claudinéia Aparecida Sales de Oliveira; Prado, María Segunda Aurora; Baby, André R; Velasco, Maria Valéria R

    2017-09-18

    Tryptophan, an amino acid found in hair proteinaceous structure is used as a marker of hair photodegradation. Also, protein loss caused by several chemical/physical treatments can be inferred by tryptophan quantification. Kynurenine is a photo-oxidation product of tryptophan, expected to be detected when hair is exposed mainly to UVB (290-320nm) radiation range. Tryptophan from hair is usually quantified directly as a solid or after alkaline hydrolysis, spectrofluorimetrically. However, these types of measure are not sufficiently specific and present several interfering substances. Thus, this work aimed to propose a quantification method for both tryptophan and kynurenine in hair samples, after alkali hydrolysis process, by using high-performance liquid chromatography (HPLC) with fluorimetric and UV detection. The tryptophan and kynurenine quantification method was developed and validated. Black, white, bleached and dyed (blond and auburn) hair tresses were used in this study. Tryptophan and kynurenine were separated within ∼9min by HPLC. Both black and white virgin hair samples presented similar concentrations of tryptophan, while bleaching caused a reduction in the tryptophan content as well as dyeing process. Unexpectedly, UV/vis radiation did not promote significantly the conversion of tryptophan into its photo-oxidation product and consequently, kynurenine was not detected. Thus, this works presented an acceptable method for quantification of tryptophan and its photooxidation metabolite kynurenine in hair samples. Also, the results indicated that bleaching and dyeing processes promoted protein/amino acids loss but tryptophan is not extensively degraded in human hair by solar radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Plasma L-Tryptophan Levels, Subjective Sleepiness and Daytime Sleep.

    Science.gov (United States)

    1980-09-01

    hydroxylase enzyme at the first step in the serotonin synthetic pathway is not saturated (Friedman et al, 1972). The availability of the amino acid...changes in rats after parachloro- phenylalanine (PCPA). Wyatt’s work (Wyatt et al, 1970) showing 1-tryptophan effects on sleep in subjects pretreated with...tryptophan hydroxylase in midbrain of the rat. Science 166: 1274-76. Brezinova, V., Loudon, J., and Oswald, I. 1972. Tryptophan and sleep. Lancet 2: 1086-87

  7. Lithium-associated hyperthyroidism.

    Science.gov (United States)

    Siyam, Fadi F; Deshmukh, Sanaa; Garcia-Touza, Mariana

    2013-08-01

    Goiters and hypothyroidism are well-known patient complications of the use of lithium for treatment of bipolar disease. However, the occurrence of lithium-induced hyperthyroidism is a more rare event. Many times, the condition can be confused with a flare of mania. Monitoring through serial biochemical measurement of thyroid function is critical in patients taking lithium. Hyperthyroidism induced by lithium is a condition that generally can be controlled medically without the patient having to discontinue lithium therapy, although in some circumstances, discontinuation of lithium therapy may be indicated. We report on a patient case of lithium-associated hyperthyroidism that resolved after discontinuation of the medication.

  8. Development of Bacillus subtilis mutants to produce tryptophan in pigs

    DEFF Research Database (Denmark)

    Bjerre, Karin; Cantor, Mette D.; Nørgaard, Jan Værum

    2017-01-01

    Objectives To generate tryptophan-overproducing Bacillus subtilis strains for in situ use in pigs, to reduce the feed cost for farmers and nitrogen pollution. Results A novel concept has been investigated—to generate B. subtilis strains able to produce tryptophan (Trp) in situ in pigs. Mutagenesis...

  9. Tryptophan analogues. 1. Synthesis and antihypertensive activity of positional isomers.

    Science.gov (United States)

    Safdy, M E; Kurchacova, E; Schut, R N; Vidrio, H; Hong, E

    1982-06-01

    A series of tryptophan analogues having the carboxyl function at the beta-position was synthesized and tested for antihypertensive activity. The 5-methoxy analogue 46 exhibited antihypertensive activity in the rat via the oral route and was much more potent than the normal tryptophan analogue. The methyl ester was found to be a critical structural feature for activity.

  10. 2-Methyl-L-tryptophan is a substrate of tryptophanase.

    Science.gov (United States)

    Faleev, N G; Gogoleva, O I; Dementieva, I S; Zakomirdina, L N; Belikov, V M

    1995-04-01

    Tryptophanase was generally considered to be inactive towards tryptophan derivatives substituted at 2-position of the indole ring. We have shown that cells containing tryptophanase catalyze the formation of 2-methyl-L-tryptophan from 2-methylindole and L-serine, and from 2-methylindole, pyruvate and ammonium ion. The kinetics of pyruvate formation from 2-methyl-L-tryptophan and its alpha-deuterated analogue catalyzed by homogeneous tryptophanase were examined. The primary deuterium isotope effect (kH/kD = 4.0) as well as the absorption spectrum of tryptophanase complex with 2-methyl-L-tryptophan indicate that the rate of enzymatic reaction of 2-methyl-L-tryptophan is in a considerable degree determined by the stage of removal of alpha-proton.

  11. The Lithium Battery: assessing the neurocognitive profile of lithium in bipolar disorder.

    Science.gov (United States)

    Malhi, Gin S; McAulay, Claire; Gershon, Samuel; Gessler, Danielle; Fritz, Kristina; Das, Pritha; Outhred, Tim

    2016-03-01

    The aim of the present study was to characterize the neurocognitive effects of lithium in bipolar disorder to inform clinical and research approaches for further investigation. Key words pertaining to neurocognition in bipolar disorder and lithium treatment were used to search recognized databases to identify relevant literature. The authors also retrieved gray literature (e.g., book chapters) known to them and examined pertinent articles from bibliographies. A limited number of studies have examined the effects of lithium on neurocognition in bipolar disorder and, although in some domains a consistent picture emerges, in many domains the findings are mixed. Lithium administration appears to reshape key components of neurocognition - in particular, psychomotor speed, verbal memory, and verbal fluency. Notably, it has a sophisticated neurocognitive profile, such that while lithium impairs neurocognition across some domains, it seemingly preserves others - possibly those vulnerable to the effects of bipolar disorder. Furthermore, its effects are likely to be direct and indirect (via mood, for example) and cumulative with duration of treatment. Disentangling the components of neurocognition modulated by lithium in the context of a fluctuating and complex illness such as bipolar disorder is a significant challenge but one that therefore demands a stratified and systematic approach, such as that provided by the Lithium Battery. In order to delineate the effects of lithium therapy on neurocognition in bipolar disorder within both research and clinical practice, a greater understanding and measurement of the relatively stable neurocognitive components is needed to examine those that indeed change with lithium treatment. In order to achieve this, we propose a Lithium Battery-Clinical and a Lithium Battery-Research that can be applied to these respective settings. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Characterisation of the tryptophan synthase alpha subunit in maize

    Directory of Open Access Journals (Sweden)

    Gierl Alfons

    2008-04-01

    Full Text Available Abstract Background In bacteria, such as Salmonella typhimurium, tryptophan is synthesized from indole-3-glycerole phosphate (IGP by a tryptophan synthase αββα heterotetramer. Plants have evolved multiple α (TSA and β (TSB homologs, which have probably diverged in biological function and their ability of subunit interaction. There is some evidence for a tryptophan synthase (TS complex in Arabidopsis. On the other hand maize (Zea mays expresses the TSA-homologs BX1 and IGL that efficiently cleave IGP, independent of interaction with TSB. Results In order to clarify, how tryptophan is synthesized in maize, two TSA homologs, hitherto uncharacterized ZmTSA and ZmTSAlike, were functionally analyzed. ZmTSA is localized in plastids, the major site of tryptophan biosynthesis in plants. It catalyzes the tryptophan synthase α-reaction (cleavage of IGP, and forms a tryptophan synthase complex with ZmTSB1 in vitro. The catalytic efficiency of the α-reaction is strongly enhanced upon complex formation. A 160 kD tryptophan synthase complex was partially purified from maize leaves and ZmTSA was identified as native α-subunit of this complex by mass spectrometry. ZmTSAlike, for which no in vitro activity was detected, is localized in the cytosol. ZmTSAlike, BX1, and IGL were not detectable in the native tryptophan synthase complex in leaves. Conclusion It was demonstrated in vivo and in vitro that maize forms a tryptophan synthase complex and ZmTSA functions as α-subunit in this complex.

  13. Destabilization of artificial biomembrane induced by the penetration of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Chen Liuhua [Department of Chemistry, Tongji University, Shanghai 200092 (China); Gan Lihua, E-mail: ganlh@tongji.edu.cn [Department of Chemistry, Tongji University, Shanghai 200092 (China); Liu Mingxian; Fan Rong; Xu Zijie; Hao Zhixian; Chen Longwu [Department of Chemistry, Tongji University, Shanghai 200092 (China)

    2011-03-15

    The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. {pi}-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 x 10{sup -3} mol L{sup -1}, the limiting molecular area of lecithin increased from 110.5 to 138.5 A{sup 2}, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m{sup -1}, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 x 10{sup 6} {Omega} and 3.573 x 10{sup -8} F to 1.391 x 10{sup 6} {Omega} and 3.340 x 10{sup -8} F when the concentration of tryptophan increased from 0 to 2 x 10{sup -3} mol L{sup -1}. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V.

  14. L-Tryptophan depletion bioreactor, a possible cancer therapy

    Directory of Open Access Journals (Sweden)

    Rolf Bambauer

    2015-04-01

    Full Text Available The cancer therapeutic strategies knownto date are not adequate for all cancer patients. Most of them are followed by a high rate of side effects and complications. The L-tryptophan depletion bioreactor is described as a possible new method of cancer therapy. L-tryptophan is an essential amino acid which has been recognized as an important cancer nutrient and its removal can lead to destruction of the tumour. Normal human cells or tumor cells cannot synthesize L-tryptophan and therefore tumor resistance is unlikely to develop. L-tryptophan is also a constituent for different bio-molecules such as Serotonin, Melatonin, and is needed for other synthesis processes in the cell growth. L-tryptophan degrading enzymes with 3 iso-enzymes called tryptophan side chain oxydase (TSO I, II, III were isolated. The 3 iso-enzymes can be differentiated by tryptic digestion. They have different molecular weights with different effectivenesses. All the TSO enzymes have heme that can catalyze essentially similar reactions involving L-tryptophan as a substrate. The most effective TSO is the type TSO III. A column which contained TSO as a bioreactor was integrated in a plasmapheresis unit and tested it in different animals. In sheep and rabbits L-tryptophan depletion in plasma was shown at 95% and 100% rates respectively by a single pass through the bioreactor. The results in immune supprimized rats with tumors were impressive, too. In 20 different tumor cell lines there were different efficacies. Brest cancer and medulloblastoma showed the greatest efficacy of L-tryptophan degrading. The gene technology of TSO production from Pseudomonas is associated with formation of endotoxins. This disadvantage can be prevented by different washing procedures or by using fungal sources for the TSO production. TSO III is developed to treat cancer diseases successfully, and has low side effects. A combination of L-tryptophan depletion with all available cancer therapies is

  15. Protection of lithium metal surfaces using chlorosilanes.

    Science.gov (United States)

    Marchioni, Filippo; Star, Kurt; Menke, Erik; Buffeteau, Thierry; Servant, Laurent; Dunn, Bruce; Wudl, Fred

    2007-11-01

    In this paper, we present a new approach for protecting metallic lithium surfaces based on a reaction between the thin native layer of lithium hydroxide present on the surface and various chlorosilane derivatives. The chemical composition of the resulting layer and the chemistry involved in layer formation were analyzed by polarization modulated infrared reflection absorption spectroscopy (PM-IRRAS), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDX). Spectroscopy shows the disappearance of surface hydroxide groups and the appearance of silicon and chloride on the lithium surface. Differential scanning calorimetry (DSC) and electrochemical impedance spectroscopy (EIS) show that this surface treatment protects the lithium from certain gas-phase reactions and is ionically conductive.

  16. Tryptophan and tryptophan-like substances in cloud water: Occurrence and photochemical fate

    Science.gov (United States)

    Bianco, Angelica; Passananti, Monica; Deguillaume, Laurent; Mailhot, Gilles; Brigante, Marcello

    2016-07-01

    This work investigates the occurrence and photochemical behaviour of tryptophan (TRP) in the cloud aqueous phase. The concentrations of tryptophan, TRYptophan LIke Substances (TRYLIS) and HUmic LIke Substances (HULIS) in real cloud water, collected between October 2013 and November 2014 at the top of the puy de Dôme station, were determined using the Excitation-Emission-Matrix (EEM) technique. The amount of free and complexed tryptophan (TRP) up to 10-7 M in cloud aqueous phase was quantified by HPLC-UV-fluorescence analysis, and its photoreactivity under sun-simulated conditions was investigated in synthetic water samples mimicking cloud aqueous phase compositions (oceanic and continental origins). TRP undergoes direct photolysis, and its degradation is enhanced in the presence of naturally occurring species able to photo-generate hydroxyl radicals (HOrad). The polychromatic quantum yield of TRP (ϕ290-340 nm TRP) is estimated to be 8.37 × 10-4 between 290 and 340 nm, corresponding to the degradation rate (RTRPd) of 1.29 × 10-11 M s-1 under our irradiation conditions. The degradation is accelerated up to 3.65 × 10-10 and 8.26 × 10-10 M s-1 in synthetic oceanic and continental cloud water samples doped with 100 μM hydrogen peroxide, respectively. Hydroxyl radical-mediated transformation leads to the generation of different functionalized and oxidized products, as well as small carboxylic acids, such as formate and acetate. Moreover, fluorescent signals of irradiated solutions indicate the formation of HULIS.

  17. A mathematical model of tryptophan metabolism via the kynurenine pathway provides insights into the effects of vitamin B-6 deficiency, tryptophan loading, and induction of tryptophan 2,3-dioxygenase on tryptophan metabolites.

    Science.gov (United States)

    Rios-Avila, Luisa; Nijhout, H Frederik; Reed, Michael C; Sitren, Harry S; Gregory, Jesse F

    2013-09-01

    Vitamin B-6 deficiency is associated with impaired tryptophan metabolism because of the coenzyme role of pyridoxal 5'-phosphate (PLP) for kynureninase and kynurenine aminotransferase. To investigate the underlying mechanism, we developed a mathematical model of tryptophan metabolism via the kynurenine pathway. The model includes mammalian data on enzyme kinetics and tryptophan transport from the intestinal lumen to liver, muscle, and brain. Regulatory mechanisms and inhibition of relevant enzymes were included. We simulated the effects of graded reduction in cellular PLP concentration, tryptophan loads and induction of tryptophan 2,3-dioxygenase (TDO) on metabolite profiles and urinary excretion. The model predictions matched experimental data and provided clarification of the response of metabolites in various extents of vitamin B-6 deficiency. We found that moderate deficiency yielded increased 3-hydroxykynurenine and a decrease in kynurenic acid and anthranilic acid. More severe deficiency also yielded an increase in kynurenine and xanthurenic acid and more pronounced effects on the other metabolites. Tryptophan load simulations with and without vitamin B-6 deficiency showed altered metabolite concentrations consistent with published data. Induction of TDO caused an increase in all metabolites, and TDO induction together with a simulated vitamin B-6 deficiency, as has been reported in oral contraceptive users, yielded increases in kynurenine, 3-hydroxykynurenine, and xanthurenic acid and decreases in kynurenic acid and anthranilic acid. These results show that the model successfully simulated tryptophan metabolism via the kynurenine pathway and can be used to complement experimental investigations.

  18. Tryptophan degradation and neopterin levels in treated rheumatoid arthritis patients.

    Science.gov (United States)

    Ozkan, Yesim; Mete, Guray; Sepici-Dincel, Aylin; Sepici, Vesile; Simsek, Bolkan

    2012-01-01

    Increased kynurenine/tryptophan-reflects trytophan degradation-and neopterin levels have been regarded as a biochemical marker of cell-mediated immune response and inflammation. This study was designed to evaluate the usefulness of tryptophan degradation and neopterin levels in active rheumatoid arthritis patients under therapy. In this case-control study, kynurenine and tryptophan levels were determined by HPLC; neopterin and tumor necrosis factor-α levels were measured with ELISA in 32 active rheumatoid arthritis patients and 20 healthy controls. Although mean values of tryptophan, kynurenine, ratio of kynurenine to tryptophan, neopterin, and tumor necrosis factor-α levels did not show statistically significant differences between patient and control groups, neopterin levels correlated positively with kynurenine (r = 0.582, p < 0.02), kynurenine/tryptophan (r = 0.486, p < 0.05), erythrocyte sedimentation rate (r = 0.472, p < 0.05) and RF (r = 0.478, p < 0.05) in the rheumatoid arthritis group. CRP levels of the patient group correlated with kynurenine levels (r = 0.524, p < 0.03). Determination of tryptophan degradation and neopterin levels in chronic inflammatory disease may provide a better understanding of progression of the disease.

  19. The High-Risk Human Papillomavirus E6 Oncogene Exacerbates the Negative Effect of Tryptophan Starvation on the Development of Chlamydia trachomatis

    Science.gov (United States)

    Sherchand, Shardulendra P.; Ibana, Joyce A.; Zea, Arnold H.; Quayle, Alison J.; Aiyar, Ashok

    2016-01-01

    Chlamydia trachomatis is an obligate intracellular pathogen that requires specific essential nutrients from the host cell, one of which is the amino acid tryptophan. In this context interferon gamma (IFNγ) is the major host protective cytokine against chlamydial infections because it induces the expression of the host enzyme, indoleamine 2,3-dioxygenase 1, that degrades tryptophan, thereby restricting bacterial replication. The mechanism by which IFNγ acts has been dissected in vitro using epithelial cell-lines such as HeLa, HEp-2, or the primary-like endocervical cell-line A2EN. All these cell-lines express the high-risk human papillomavirus oncogenes E6 & E7. While screening cell-lines to identify those suitable for C. trachomatis co-infections with other genital pathogens, we unexpectedly found that tryptophan starvation did not completely block chlamydial development in cell-lines that were HR-HPV negative, such as C33A and 293. Therefore, we tested the hypothesis that HR-HPV oncogenes modulate the effect of tryptophan starvation on chlamydial development by comparing chlamydial development in HeLa and C33A cell-lines that were both derived from cervical carcinomas. Our results indicate that during tryptophan depletion, unlike HeLa, C33A cells generate sufficient intracellular tryptophan via proteasomal activity to permit C. trachomatis replication. By generating stable derivatives of C33A that expressed HPV16 E6, E7 or E6 & E7, we found that E6 expression alone was sufficient to convert C33A cells to behave like HeLa during tryptophan starvation. The reduced tryptophan levels in HeLa cells have a biological consequence; akin to the previously described effect of IFNγ, tryptophan starvation protects C. trachomatis from clearance by doxycycline in HeLa but not C33A cells. Curiously, when compared to the known Homo sapiens proteome, the representation of tryptophan in the HR-HPV E6 & E6AP degradome is substantially lower, possibly providing a mechanism that

  20. Exploring the mechanism of tryptophan 2,3-dioxygenase

    Science.gov (United States)

    Thackray, Sarah J.; Mowat, Christopher G.; Chapman, Stephen K.

    2008-01-01

    The haem proteins TDO (tryptophan 2,3-dioxygenase) and IDO (indoleamine 2,3-dioxygenase) are specific and powerful oxidation catalysts that insert one molecule of dioxygen into L-tryptophan in the first and rate-limiting step in the kynurenine pathway. Recent crystallographic and biochemical analyses of TDO and IDO have greatly aided our understanding of the mechanisms employed by these enzymes in the binding and activation of dioxygen and tryptophan. In the present paper, we briefly discuss the function, structure and possible catalytic mechanism of these enzymes. PMID:19021508

  1. Metabolism and serum levels of tryptophan in senile cataract patients.

    Science.gov (United States)

    Costa, C; Angi, M R; De Carli, M; Vanzan, S; Allegri, G

    1982-03-30

    In order to clarify the role of tryptophan in the patogenesis of senile cataract, we have studied the serum total and free levels of tryptophan in cataract patients as compared with age and sex-matched controls, and the urinary excretion of 10 metabolites after oral load of the amino acid. This excretion increases in the cataract group both as total per cent and as kynurenine. No difference has been found in the free and total serum tryptophan between normal subjects and cataract patients. A possible role of the kynurenines in the pathogenesis of senile cataract is suggested.

  2. Relation between proteins tertiary structure, tryptophan fluorescence lifetimes and tryptophan S(o)→(1)L(b) and S(o)→(1)L(a) transitions. Studies on α1-acid glycoprotein and β-lactoglobulin.

    Science.gov (United States)

    Albani, Jihad René

    2011-05-01

    We measured fluorescence lifetimes and fluorescence spectra (excitation and emission) of tryptophan residues of α(1)-acid glycoprotein (three Trp residues) and β-lactoglobulin (two Trp residues) in absence and presence of 450 μM progesterone. Progesterone binds only to α(1)-acid glycoprotein. In absence of progesterone, each of the two proteins displays three fluorescence lifetimes. Addition of progesterone induces a partial inhibition of the S(o) → (1)L(a) transition without affecting fluorescence lifetimes. The same experiments performed in presence of denatured proteins in 6 M guanidine show that addition of progesterone inhibits partially the S(o) → (1)L(a) transition and its peak is 15 nm shifted to the red compared to that obtained for native proteins. However, the S(o) → (1)L(b) transition position peak is not affected by protein denaturation. Thus, the tertiary structure of the protein plays an important role by modulating the tryptophan electronic transitions. Fluorescence emission decay recorded in absence and presence of progesterone yields three fluorescence lifetimes whether proteins are denatured or not. Thus, protein tertiary structure is not responsible for the presence of three fluorescence lifetimes. These characterize tryptophan substructures reached at the excited states and which population (pre-exponential values) depend on the tryptophan residues interaction with their microenvironment(s) and thus on the global conformation of the protein.

  3. Lithium and Pregnancy

    Science.gov (United States)

    ... best live chat Live Help Fact Sheets Share Lithium and Pregnancy Saturday, 20 September 2014 In every ... risk. This sheet talks about whether exposure to lithium may increase the risk for birth defects over ...

  4. 基于热管技术的锂离子动力电池散热系统%Thermal control module using heat pipe for lithium-ion battery

    Institute of Scientific and Technical Information of China (English)

    曾健; 陆龙生; 陈维; 何浩

    2015-01-01

    基于对大功率锂离子动力电池温升和温度场分布的研究,设计了一种基于热管技术的锂离子动力电池散热模块。实验结果表明,采用所设计的散热模块能够有效降低电池壁面温度,使其壁面最高温度低于40℃,与无热管理条件相比降幅高达10℃,满足锂离子动力电池最佳工作温度范围。对散热模块与纯热管的散热性能进行对比,发现散热模块比单纯使用热管的散热效果和均温效果更好。此外,采用有限元模拟软件 Fluent 分析复合风冷翅片和 U 型热管模块蒸发段几何尺寸对散热模块性能的影响,发现复合风冷翅片能够有效提高模块散热性能以及不同的蒸发段几何分布会影响电池壁面温度和温度场分布。当 U 型热管蒸发段的垂直段和水平段长度比为1时,散热模块散热性能最好。%Based on our research on temperature rise and temperature field of high-capacity lithium-ion battery for vehicles,a thermal control module using heat pipe was designed. Our experiment showed that the thermal control module could decrease the wall temperature of the battery efficiently, restricting it below 40℃,a reduction of over 10℃ compared with that without thermal control,which met the favorable operation temperature range for lithium-ion battery. Comparison of performance between the thermal control module and heat pipe itself showed better performance of heat dissipation and temperature uniformity by using the thermal control module. Additionally,research with FEM simulation software Fluent on the influence of forced convection fins and geometry of the evaporator of U-shape heat pipe on the performance of module was conducted. Forced convection fins could obviously enhance the performance of the module,and geometry of the evaporator of the U-shape heat pipe could affect the temperature field of the battery. When the ratio of vertical length to horizontal length was 1,best

  5. protein, tryptophan and lysine contents in quality protien maize ...

    African Journals Online (AJOL)

    owner

    for human nutrition recommended by Food and Agriculture Organization in ... METHODS: The protein, tryptophan and lysine contents of improved ... This study revealed the fact that genetic factor influences the protein, ... Ethiop J Health Sci.

  6. Micro-environmental influences on the fluorescence of tryptophan

    Science.gov (United States)

    Sun, Feng; Zong, Wansong; Liu, Rutao; Chai, Jun; Liu, Ying

    2010-07-01

    The fluorescence characteristics of protein molecules are mainly due to their tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe) residues, among which tryptophan is the most important. Studying the influence of the micro-environment on tryptophan fluorescence can give us direct and convincing evidence for changes of protein structure and function. In this paper, fluorescence spectroscopy was used to evaluate the changes of tryptophan fluorescence under a variety of micro-environmental conditions (temperature, pH, polarity, presence of surfactants and oxidants) and the mechanisms responsible. This study not only presents more direct evidence to explain how and why the protein fluorescence spectra change, but also provides a new method for analyzing the effect of environmental changes on protein function.

  7. Tryptophan rich diet as a new approach to study the serotoninergic enteropancreatic axis.

    OpenAIRE

    Goke, B.; Richter, G; Keim, V; Arnold, R

    1987-01-01

    The influence of a tryptophan enriched diet (L-tryptophan added as 1% of total diet), fed over 10 days, on the rat duodenum and pancreas was studied by immunohistology, measurements of serotonin and tryptophan tissue concentrations by HPLC, and incubations of pancreatic lobules. Ingestion of a tryptophan enriched diet resulted in increased contents of tryptophan and serotonin in the duodenum that was not accompanied by a significant change of the serotonin cell density. Neither basal nor CCK-...

  8. Tryptophan degradation in women with breast cancer: a pilot study

    Directory of Open Access Journals (Sweden)

    Schubert Christine M

    2011-05-01

    Full Text Available Abstract Background Altered tryptophan metabolism and indoleamine 2,3-dioxygenase activity are linked to cancer development and progression. In addition, these biological factors have been associated with the development and severity of neuropsychiatric syndromes, including major depressive disorder. However, this biological mechanism associated with both poor disease outcomes and adverse neuropsychiatric symptoms has received little attention in women with breast cancer. Therefore, a pilot study was undertaken to compare levels of tryptophan and other proteins involved in tryptophan degradation in women with breast cancer to women without cancer, and secondarily, to examine levels in women with breast caner over the course of chemotherapy. Findings Blood samples were collected from women with a recent diagnosis of breast cancer (n = 33 before their first cycle of chemotherapy and after their last cycle of chemotherapy. The comparison group (n = 24 provided a blood sample prior to breast biopsy. Plasma concentrations of tryptophan, kynurenine, and tyrosine were determined. The kynurenine to tryptophan ratio (KYN/TRP was used to estimate indoleamine 2,3-dioxygenase activity. On average, the women with breast cancer had lower levels of tryptophan, elevated levels of kynurenine and tyrosine and an increased KYN/TRP ratio compared to women without breast cancer. There was a statistically significant difference between the two groups in the KYN/TRP ratio (p = 0.036, which remained elevated in women with breast cancer throughout the treatment trajectory. Conclusions The findings of this pilot study suggest that increased tryptophan degradation may occur in women with early-stage breast cancer. Given the multifactorial consequences of increased tryptophan degradation in cancer outcomes and neuropsychiatric symptom manifestation, this biological mechanism deserves broader attention in women with breast cancer.

  9. Plasma tryptophan concentration in depressive illness and mania.

    Science.gov (United States)

    Peet, M; Moody, J P; Worrall, E P; Walker, P; Naylor, G J

    1976-03-01

    Total and free plasma trytophan levels were measured in depressive and manic patients before and after recovery. No change was found in total or free plasma trytophan concentration on recovery from depressive illness. Free plasma tryptophan levels were higher in recovered manics than in active manics, and a group of four manic patients tested before and after recovery showed a significant increase in free plasma tryptophan concentration on recovery.

  10. Efficient Asymmetric Synthesis of Tryptophan Analogues Having Useful Photophysical Properties

    Science.gov (United States)

    Talukder, Poulami; Chen, Shengxi; Arce, Pablo M.

    2014-01-01

    Two new fluorescent probes of protein structure and dynamics have been prepared by concise asymmetric syntheses using the Schöllkopf chiral auxiliary. The site-specific incorporation of one probe into dihydrofolate reductase is reported. The utility of these tryptophan derivatives lies in their absorption and emission maxima which differ from those of tryptophan, as well as in their large Stokes shifts and high molar absorptivities. PMID:24392870

  11. Kernel modifications and tryptophan content in QPM segregating generations

    Directory of Open Access Journals (Sweden)

    -Ignjatović-Micić Dragana

    2010-01-01

    Full Text Available Maize has poor nutritional value due to deficiency of two essential amino acids - tryptophan and lysine. Although recessive opaque2 (o2 mutation significantly increases their content in the endosperm, incorporation of opaque2 into high yielding cultivars was not commercially successful, because of its numerous agronomic and processing problems due to soft endosperm. Quality protein maize - QPM has lately been introduced as opaque2 maize with improved endosperm hardness and improved agronomic traits, but mostly within tropical and subtropical germplasm. The ongoing breeding project at MRI includes improvement of MRI opaque2 lines and conversion of standard lines to QPM germplasm. The main selection steps in QPM breeding involve assessing kernel modifications and tryptophan level in each generation. Herein, we present the results of the analysis for these traits on F3 and BC1F1 generations of QPM x opaque2, opaque2 x QPM and standard lines x QPM crosses. The results showed that the majority the genotypes had kernel types 2 and 3 (good modifications. The whole grain tryptophan content in F3 and BC1F1 genotypes of crosses between QPM and opaque2 germplasm was at the quality protein level, with a few exceptions. All BC1F1 genotypes of standard lines x QPM had tryptophan content in the range of normal maize, while majority of F3 genotypes had tryptophan content at level of QPM. The progeny (with increased tryptophan levels of QPM and opaque2 crosses had significantly higher tryptophan content compared to the progeny of crosses between standard and QPM lines - 0.098 to 0.114 and 0.080, respectively. All genotypes that had poorly modified kernels and/or low tryptophan content will be discarded from further breeding.

  12. Utilization of DL- and L-tryptophan in young pigs

    NARCIS (Netherlands)

    Schutte, J.B.; Van Weerden, E.J.; Koch, F.

    1988-01-01

    Two trials involving young pigs (total numbers 288 and 400, respectively) were performed to compare the biological activity of Dl- and L-tryptophan under restricted (trial 1) and ad libitum (trial 2) feeding conditions. In trial 1, three additions of Dl-tryptophan (0·3, 0·6 and 0·9 g/kg) and two

  13. Lithium batteries; Les accumulateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This workshop on lithium batteries is divided into 4 sections dealing with: the design and safety aspects, the cycling, the lithium intercalation and its modeling, and the electrolytes. These 4 sections represent 19 papers and are completed by a poster session which corresponds to 17 additional papers. (J.S.)

  14. Lithium metal oxide electrodes for lithium batteries

    Science.gov (United States)

    Thackeray, Michael M.; Kim, Jeom-Soo; Johnson, Christopher S.

    2008-01-01

    An uncycled electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula Li.sub.(2+2x)/(2+x)M'.sub.2x/(2+x)M.sub.(2-2x)/(2+x)O.sub.2-.delta., in which 0.ltoreq.xbatteries containing the electrodes.

  15. Fiber Acousto-Electro-Optic Modulator

    Institute of Scientific and Technical Information of China (English)

    Anen; Jiang

    2003-01-01

    A new kind of fiber acousto-electro-optic modulator is made by using Lithium Niobate crystal. This kind of modulator can be used in fiber communication, and its center frequency can be changed by directed current voltages.

  16. Lithium use in batteries

    Science.gov (United States)

    Goonan, Thomas G.

    2012-01-01

    Lithium has a number of uses but one of the most valuable is as a component of high energy-density rechargeable lithium-ion batteries. Because of concerns over carbon dioxide footprint and increasing hydrocarbon fuel cost (reduced supply), lithium may become even more important in large batteries for powering all-electric and hybrid vehicles. It would take 1.4 to 3.0 kilograms of lithium equivalent (7.5 to 16.0 kilograms of lithium carbonate) to support a 40-mile trip in an electric vehicle before requiring recharge. This could create a large demand for lithium. Estimates of future lithium demand vary, based on numerous variables. Some of those variables include the potential for recycling, widespread public acceptance of electric vehicles, or the possibility of incentives for converting to lithium-ion-powered engines. Increased electric usage could cause electricity prices to increase. Because of reduced demand, hydrocarbon fuel prices would likely decrease, making hydrocarbon fuel more desirable. In 2009, 13 percent of worldwide lithium reserves, expressed in terms of contained lithium, were reported to be within hard rock mineral deposits, and 87 percent, within brine deposits. Most of the lithium recovered from brine came from Chile, with smaller amounts from China, Argentina, and the United States. Chile also has lithium mineral reserves, as does Australia. Another source of lithium is from recycled batteries. When lithium-ion batteries begin to power vehicles, it is expected that battery recycling rates will increase because vehicle battery recycling systems can be used to produce new lithium-ion batteries.

  17. Flavin-dependent Tryptophan Halogenases and Their Use in Formation of Novel Tryptophan Derived Compounds

    Institute of Scientific and Technical Information of China (English)

    CHEN Xian-Ping; HUANG Mei-Fa; WANG Bin

    2008-01-01

    Ravin-dependent halogenases are now known to play a significant role in the introduction of chloride and bro- mide into activated organic molecules. Herein a new strategy was reported to formate monodechloroaminopyrrolni-trin derivative 3-(2-amino-4-chlorophenyl)pyrrole, which is a key intermediate for the analysis and mutagenesis of pyrrolnitrin biosynthesis, by combinatorial biosynthesis using regioselective tryptophan halogenases. The successful production in Pseudomonas, with combinatorial cultivating method, demonstrates the feasibility of the new ap-proach to modify and analyze these important secondary metabolite pathways.

  18. The Role of Placental Tryptophan Catabolism

    Science.gov (United States)

    Sedlmayr, Peter; Blaschitz, Astrid; Stocker, Roland

    2014-01-01

    This review discusses the mechanisms and consequences of degradation of tryptophan (Trp) in the placenta, focusing mainly on the role of indoleamine 2,3-dioxygenase-1 (IDO1), one of three enzymes catalyzing the first step of the kynurenine pathway of Trp degradation. IDO1 has been implicated in regulation of feto-maternal tolerance in the mouse. Local depletion of Trp and/or the presence of metabolites of the kynurenine pathway mediate immunoregulation and exert antimicrobial functions. In addition to the decidual glandular epithelium, IDO1 is localized in the vascular endothelium of the villous chorion and also in the endothelium of spiral arteries of the decidua. Possible consequences of IDO1-mediated catabolism of Trp in the endothelium encompass antimicrobial activity and immunosuppression, as well as relaxation of the placental vasotonus, thereby contributing to placental perfusion and growth of both placenta and fetus. It remains to be evaluated whether other enzymes mediating Trp oxidation, such as indoleamine 2,3-dioxygenase-2, Trp 2,3-dioxygenase, and Trp hydroxylase-1 are of relevance to the biology of the placenta. PMID:24904580

  19. The tryptophan aminotransferase Tam1 catalyses the single biosynthetic step for tryptophan-dependent pigment synthesis in Ustilago maydis.

    Science.gov (United States)

    Zuther, Katja; Mayser, Peter; Hettwer, Ursula; Wu, Wenying; Spiteller, Peter; Kindler, Bernhard L J; Karlovsky, Petr; Basse, Christoph W; Schirawski, Jan

    2008-04-01

    Tryptophan is a precursor for many biologically active secondary metabolites. We have investigated the origin of indole pigments first described in the pityriasis versicolor-associated fungus Malassezia furfur. Some of the identified indole pigments have properties potentially explaining characteristics of the disease. As M. furfur is not amenable to genetic manipulation, we used Ustilago maydis to investigate the pathway leading to pigment production from tryptophan. We show by high-performance liquid chromatography, mass spectrometry and nuclear magnetic resonance analysis that the compounds produced by U. maydis include those putatively involved in the etiology of pityriasis versicolor. Using a reverse genetics approach, we demonstrate that the tryptophan aminotransferase Tam1 catalyses pigment biosynthesis by conversion of tryptophan into indolepyruvate. A forward genetics approach led to the identification of mutants incapable of producing the pigments. These mutants were affected in the sir1 gene, presumably encoding a sulphite reductase. In vitro experiments with purified Tam1 showed that 2-oxo 4-methylthio butanoate serves as a substrate linking tryptophan deamination to sulphur metabolism. We provide the first direct evidence that these indole pigments form spontaneously from indolepyruvate and tryptophan without any enzymatic activity. This suggests that compounds with a proposed function in M. furfur-associated disease consist of indolepyruvate-derived spontaneously generated metabolic by-products.

  20. A distinct profile of tryptophan metabolism along the kynurenine pathway downstream of Toll-like receptor activation in irritable bowel syndrome

    Directory of Open Access Journals (Sweden)

    Gerard eClarke

    2012-05-01

    Full Text Available Irritable bowel syndrome (IBS, a disorder of the brain-gut axis, is characterised by the absence of reliable biological markers. Tryptophan is an essential amino acid that serves as a precursor to serotonin but which can alternatively be metabolised along the kynurenine pathway leading to the production of other neuroactive agents. We previously reported an increased degradation of tryptophan along this immunoresponsive pathway in IBS. Recently, altered cytokine production following activation of specific members of the toll-like receptor (TLR family (TLR1-9 has also been demonstrated in IBS. However, the relationship between TLR activation and kynurenine pathway activity in IBS is unknown. In this study, we investigated whether activation of specific TLRs elicits exaggerated kynurenine production in IBS patients compared to controls. Whole blood from IBS patients and healthy controls was cultured with a panel of nine different TLR agonists for 24 hours. Cell culture supernatants were then analysed for both tryptophan and kynurenine concentrations, as were plasma samples from both cohorts. IBS subjects had an elevated plasma kynurenine:tryptophan ratio compared to healthy controls. Furthermore, we demonstrated a differential downstream profile of kynurenine production subsequent to TLR activation in IBS patients compared to healthy controls. This profile included alterations at TLR1/2, TLR2, TLR3, TLR5, TLR7 and TLR8. Our data expands on our previous understanding of altered tryptophan metabolism in IBS and suggests that measurement of tryptophan metabolites downstream of TLR activation may ultimately find utility as components of a biomarker panel to aid gastroenterologists in the diagnosis of IBS. Furthermore, these studies implicate the modulation of TLRs as means through which aberrant tryptophan metabolism along the kynurenine pathway can be controlled, a novel potential therapeutic strategy in this and other disorders.

  1. Kynurenine pathway in psychosis: evidence of increased tryptophan degradation.

    LENUS (Irish Health Repository)

    Barry, Sandra

    2009-05-01

    The kynurenine pathway of tryptophan degradation may serve to integrate disparate abnormalities heretofore identified in research aiming to elucidate the complex aetiopathogenesis of psychotic disorders. Post-mortem brain tissue studies have reported elevated kynurenine and kynurenic acid in the frontal cortex and upregulation of the first step of the pathway in the anterior cingulate cortex of individuals with schizophrenia. In this study, we examined kynurenine pathway activity by measuring tryptophan breakdown, a number of pathway metabolites and interferon gamma (IFN-gamma), which is the preferential activator of the first-step enzyme, indoleamine dioxygenase (IDO), in the plasma of patients with major psychotic disorder. Plasma tryptophan, kynurenine pathway metabolites were measured using high-performance liquid chromatography (HPLC) in 34 patients with a diagnosis on the psychotic spectrum (schizophrenia or schizoaffective disorder) and in 36 healthy control subjects. IFN-gamma was measured using enzyme-linked immunosorbent assay (ELISA). The mean tryptophan breakdown index (kynurenine\\/tryptophan) was significantly higher in the patient group compared with controls (P < 0.05). IFN-gamma measures did not differ between groups (P = 0.23). No relationship was found between measures of psychopathology, symptom severity and activity in the first step in the pathway. A modest correlation was established between the tryptophan breakdown index and illness duration. These results provide evidence for kynurenine pathway upregulation, specifically involving the first enzymatic step, in patients with major psychotic disorder. Increased tryptophan degradation in psychoses may have potential consequences for the treatment of these disorders by informing the development of novel therapeutic compounds.

  2. Decreased tryptophan metabolism in patients with autism spectrum disorders

    Science.gov (United States)

    2013-01-01

    Background Autism spectrum disorders (ASDs) are relatively common neurodevelopmental conditions whose biological basis has been incompletely determined. Several biochemical markers have been associated with ASDs, but there is still no laboratory test for these conditions. Methods We analyzed the metabolic profile of lymphoblastoid cell lines from 137 patients with neurodevelopmental disorders with or without ASDs and 78 normal individuals, using Biolog Phenotype MicroArrays. Results Metabolic profiling of lymphoblastoid cells revealed that the 87 patients with ASD as a clinical feature, as compared to the 78 controls, exhibited on average reduced generation of NADH when tryptophan was the sole energy source. The results correlated with the behavioral traits associated with either syndromal or non-syndromal autism, independent of the genetic background of the individual. The low level of NADH generation in the presence of tryptophan was not observed in cell lines from non-ASD patients with intellectual disability, schizophrenia or conditions exhibiting several similarities with syndromal autism except for the behavioral traits. Analysis of a previous small gene expression study found abnormal levels for some genes involved in tryptophan metabolic pathways in 10 patients. Conclusions Tryptophan is a precursor of important compounds, such as serotonin, quinolinic acid, and kynurenic acid, which are involved in neurodevelopment and synaptogenesis. In addition, quinolinic acid is the structural precursor of NAD+, a critical energy carrier in mitochondria. Also, the serotonin branch of the tryptophan metabolic pathway generates NADH. Lastly, the levels of quinolinic and kynurenic acid are strongly influenced by the activity of the immune system. Therefore, decreased tryptophan metabolism may alter brain development, neuroimmune activity and mitochondrial function. Our finding of decreased tryptophan metabolism appears to provide a unifying biochemical basis for ASDs and

  3. Indole-3-Acetic Acid Biosynthesis in the Mutant Maize orange pericarp, a Tryptophan Auxotroph.

    Science.gov (United States)

    Wright, A D; Sampson, M B; Neuffer, M G; Michalczuk, L; Slovin, J P; Cohen, J D

    1991-11-15

    The maize mutant orange pericarp is a tryptophan auxotroph, which results from mutation of two unlinked loci of tryptophan synthase B. This mutant was used to test the hypothesis that tryptophan is the precursor to the plant hormone indole-3-acetic acid (IAA). Total IAA in aseptically grown mutant seedlings was 50 times greater than in normal seedlings. In mutant seedlings grown on media containing stable isotopelabeled precursors, IAA was more enriched than was tryptophan. No incorporation of label into IAA from tryptophan could be detected. These results establish that IAA can be produced de novo without tryptophan as an intermediate.

  4. Lithium associated autoimmune thyroiditis.

    OpenAIRE

    Shimizu, M; Hirokawa, M.; T. Manabe; Shimozuma, K; Sonoo, H; Harada, T.

    1997-01-01

    A case of autoimmune thyroiditis after long term treatment with lithium is described in a 29 year old Japanese woman with manic depression. Positive serum antithyroglobulin and antimicrosomal antibodies, diffuse goitre, and microscopic chronic thyroiditis, as well as the clinical history of long term lithium treatment were suggestive of lithium associated autoimmune thyroiditis. Microscopically, there was a mild degree of interstitial fibrosis and a moderate degree of lymphocytic infiltration...

  5. Determination of tryptophan and tryptophan metabolites in grape must and wine.

    Science.gov (United States)

    Hoenicke, K; Simat, T J; Steinhart, H; Christoph, N; Köhler, H J; Schwab, A

    1999-01-01

    Tryptophan (Trp) and its metabolites, especially indole-3-acetic acid (IAA), are considered as potential precursors of 2-aminoacetophenone (AAP), an aroma compound which causes the "untypical aging off-flavor" (UTA) in Vitis vinifera white wines. In this study RP-HPLC with fluorescence detection was used for the qualitative and quantitative analysis of Trp and Trp-metabolites in 39 grapes, 22 grape musts and 16 wines, to which different viticultural conditions (ripeness, pruning, strip of leaves, soil condition) have been applied. A sensitive and selective determination was achieved after solid phase extraction using an anion exchange material. Only traces of Trp-metabolites could be determined in the examined grapes and grape musts, but their amounts increased significantly during fermentation, whereas the amount of Trp decreased. Different viticultural measures, besides the time of grape harvest, showed no significant influences on the amount of Trp and Trp-metabolites.

  6. Lithium nephrotoxicity revisited.

    Science.gov (United States)

    Grünfeld, Jean-Pierre; Rossier, Bernard C

    2009-05-01

    Lithium is widely used to treat bipolar disorder. Nephrogenic diabetes insipidus (NDI) is the most common adverse effect of lithium and occurs in up to 40% of patients. Renal lithium toxicity is characterized by increased water and sodium diuresis, which can result in mild dehydration, hyperchloremic metabolic acidosis and renal tubular acidosis. The concentrating defect and natriuretic effect develop within weeks of lithium initiation. After years of lithium exposure, full-blown nephropathy can develop, which is characterized by decreased glomerular filtration rate and chronic kidney disease. Here, we review the clinical and experimental evidence that the principal cell of the collecting duct is the primary target for the nephrotoxic effects of lithium, and that these effects are characterized by dysregulation of aquaporin 2. This dysregulation is believed to occur as a result of the accumulation of cytotoxic concentrations of lithium, which enters via the epithelial sodium channel (ENaC) on the apical membrane and leads to the inhibition of signaling pathways that involve glycogen synthase kinase type 3beta. Experimental and clinical evidence demonstrates the efficacy of the ENaC inhibitor amiloride for the treatment of lithium-induced NDI; however, whether this agent can prevent the long-term adverse effects of lithium is not yet known.

  7. Incorporation of tryptophan analogues into the lantibiotic nisin.

    Science.gov (United States)

    Zhou, Liang; Shao, Jinfeng; Li, Qian; van Heel, Auke J; de Vries, Marcel P; Broos, Jaap; Kuipers, Oscar P

    2016-05-01

    Lantibiotics are posttranslationally modified peptides with efficient inhibitory activity against various Gram-positive bacteria. In addition to the original modifications, incorporation of non-canonical amino acids can render new properties and functions to lantibiotics. Nisin is the most studied lantibiotic and contains no tryptophan residues. In this study, a system was constructed to incorporate tryptophan analogues into nisin, which included the modification machinery (NisBTC) and the overexpression of tryptophanyl-tRNA synthetase (TrpRS). Tryptophan and three different tryptophan analogues (5-fluoroTrp (5FW), 5-hydroxyTrp (5HW) and 5-methylTrp (5MeW)) were successfully incorporated at four different positions of nisin (I1W, I4W, M17W and V32W). The incorporation efficiency of tryptophan analogues into mutants I1W, M17W and V32W was over 97 %, while the mutant I4W showed relatively low incorporation efficiency (69-93 %). The variants with 5FW showed relatively higher production yield, while 5MeW-containing variants showed the lowest yield. The dehydration efficiency of serines or threonines was affected by the tryptophan mutants of I4W and V32W. The affinity of the peptides for the cation-ion exchange and reverse phase chromatography columns was significantly reduced when 5HW was incorporated. The antimicrobial activity of IIW and its 5FW analogue both decreased two times compared to that of nisin, while that of its 5HW analogue decreased four times. The 5FW analogue of I4W also showed two times decreased activity than nisin. However, the mutant M17W and its 5HW analogue both showed 32 times reduced activity relative to that of nisin.

  8. Maintenance valine, isoleucine, and tryptophan requirements for poultry.

    Science.gov (United States)

    de Lima, M B; Sakomura, N K; Dorigam, J C P; da Silva, E P; Ferreira, N T; Fernandes, J B K

    2016-04-01

    Poultry maintenance requirements for valine, isoleucine, and tryptophan were measured by nitrogen balance using different unit systems. The nitrogen balance trial lasted 5 d with 48 h of fasting (with roosters receiving only water+sucrose) and the last 72 h for feeding and excreta collection. Forty grams of each diet first-limiting in valine, isoleucine, or tryptophan was fed by tube each day (3 d) to give a range of intakes from 0 to 101, 0 to 119, and 0 to 34 mg/kg BW d of valine, isoleucine, and tryptophan, respectively. A nitrogen-free diet containing energy, vitamins, and minerals, meeting the rooster requirements, was offered ad libitum during these three d. To confirm that the amino acids studied were limiting, a treatment was added with a control diet formulated by adding 0.24 g/kg of L-valine, 0.21 g/kg of L-isoleucine, and 0.10 g/kg of L-tryptophan to the diets with lower amino acid level. Excreta were collected during the last 3 d of the balance period and the nitrogen content of the excreta was analyzed. For each amino acid, a linear regression between nitrogen retention (NR) and amino acid intake was performed. The equations from linear regression were: NR=-98.6 (±10.1)+2.4 (±0.2)×Val, NR=-46.9 (±7.1)+2.3 (±0.1)×Ile, NR=-39.5 (±7.7)+7.3 (±0.4)×Trp; where Val, Ile, and Trp are the intakes of valine, isoleucine, and tryptophan in mg/kg body weight per d, respectively. The valine, isoleucine, and tryptophan required to maintain the body at zero NR were calculated to be 41, 20, and 5 mg/kg body weight per d, respectively. For the system unit mg per kg of metabolic weight, the intake of valine, isoleucine, and tryptophan was 59, 32, and 9, respectively. Considering the degree of maturity of the animal and body protein content (BPm (0.73)×u), the amounts of valine, isoleucine, and tryptophan required for maintenance were calculated to be 247, 134, and 37 mg per unit of maintenance protein (BPm (0.73)×u) per d. Maintenance requirement is more

  9. Heme-containing dioxygenases involved in tryptophan oxidation.

    Science.gov (United States)

    Millett, Elizabeth S; Efimov, Igor; Basran, Jaswir; Handa, Sandeep; Mowat, Christopher G; Raven, Emma Lloyd

    2012-04-01

    Heme iron is often used in biology for activation of oxygen. The mechanisms of oxygen activation by heme-containing monooxygenases (the cytochrome P450s) are well known, and involve formation of a Compound I species, but information on the heme-containing dioxygenase enzymes involved in tryptophan oxidation lags far behind. In this review, we gather together information emerging recently from structural, mechanistic, spectroscopic, and computational approaches on the heme dioxygenase enzymes involved in tryptophan oxidation. We explore the subtleties that differentiate various heme enzymes from each other, and use this to piece together a developing picture for oxygen activation in this particular class of heme-containing dioxygenases.

  10. Dynamic behavior in mathematical models of the tryptophan operon

    Science.gov (United States)

    Santillán, Moisés; Mackey, Michael C.

    2001-03-01

    This paper surveys the general theory of operon regulation as first formulated by Goodwin and Griffith, and then goes on to consider in detail models of regulation of tryptophan production by Bliss, Sinha, and Santillán and Mackey, and the interrelationships between them. We further give a linear stability analysis of the Santillán and Mackey model for wild type E. coli as well as three different mutant strains that have been previously studied in the literature. This stability analysis indicates that the tryptophan production systems should be stable, which is in accord with our numerical results.

  11. Role of brain tryptophan and serotonin in secondary anorexia.

    Science.gov (United States)

    Rossi-Fanelli, Filippo; Laviano, Alessandro

    2003-01-01

    Anorexia and reduced energy intake contribute to worsen the prognosis of patients suffering from a number of chronic diseases, by promoting skeletal muscle wasting, leading to the development of malnutrition and eventually cachexia. The pathogenesis of cancer anorexia is still matter of debate. Many possible mediators, including hormones, peptides, and neurotransmitters, appear to be involved. However, consistent animal and clinical data suggest that brain tryptophan and serotonin may represent a common final pathway shared by many contributing factors. Supporting this hypothesis, recent data showed that the manipulation of brain tryptophan availability ameliorates anorexia and food intake in cancer patients.

  12. Phasor approaches simplify the analysis of tryptophan fluorescence data in protein denaturation studies

    NARCIS (Netherlands)

    Bader, A.N.; Visser, N.V.; Amerongen, van H.; Visser, A.J.W.G.

    2014-01-01

    The intrinsic fluorescence of tryptophan is frequently used to investigate the structure of proteins. The analysis of tryptophan fluorescence data is challenging: fluorescence (anisotropy) decays typically have multiple lifetime (correlation time) components and fluorescence spectra are broad and ex

  13. XPS, time-of-flight-SIMS and polarization modulation IRRAS study of Cr{sub 2}O{sub 3} thin film materials as anode for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Li Juntao [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045), Ecole Nationale Superieure de Chimie de Paris, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Maurice, Vincent [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045), Ecole Nationale Superieure de Chimie de Paris, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France)], E-mail: vincent-maurice@enscp.fr; Swiatowska-Mrowiecka, Jolanta; Seyeux, Antoine; Zanna, Sandrine; Klein, Lorena [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045), Ecole Nationale Superieure de Chimie de Paris, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Sun Shigang [State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)], E-mail: sgsun@xmu.edu.cn; Marcus, Philippe [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045), Ecole Nationale Superieure de Chimie de Paris, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France)], E-mail: philippe-marcus@enscp.fr

    2009-05-30

    Ultra-thin Cr{sub 2}O{sub 3} films (12.0, 17.3 and 29.6 nm thick) were produced on Cr metal by thermal oxidation, and their electrochemical properties in 1 M LiClO{sub 4} in propylene carbonate (PC) were investigated by cyclic voltammetry and chronopotentiometry. The reductive electrolyte decomposition and the conversion/deconversion process were observed and analyzed by X-ray photoelectron spectroscopy (XPS), polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The initial irreversible capacity due to the reduction of electrolyte and the incomplete deconversion process during the first cycle is 70% of the first discharge capacity. A stable charge/discharge capacity of 460 mAh g{sup -1} was obtained in the 3rd to 10th cycles. XPS and PM-IRRAS evidenced the growth of a solid electrolyte interphase (SEI) layer that is constituted of Li{sub 2}CO{sub 3} formed by reductive decomposition of the electrolyte. The SEI layer thickness and/or density is modified by the conversion/deconversion reaction. ToF-SIMS evidenced the volume expansion/shrink resulting from the conversion/deconversion reaction. ToF-SIMS also revealed an incomplete conversion process limited by mass transport, which partitions the oxide into a converted outer part assigned to Li{sub 2}O containing Cr traces and an unconverted inner part ascribed to Cr{sub 2}O{sub 3} or lower Cr oxide containing Li. It was found that the deconversion re-homogenizes the oxide film in a single layer but with lithium trapped in it. The present study provides a detailed understanding of the interfacial reaction on the oxide anode undergoing a conversion/deconversion reaction.

  14. Physiological studies of tryptophan transport and tryptophanase operon induction in Escherichia coli.

    Science.gov (United States)

    Yanofsky, C; Horn, V; Gollnick, P

    1991-10-01

    Escherichia coli forms three permeases that can transport the amino acid tryptophan: Mtr, AroP, and TnaB. The structural genes for these permeases reside in separate operons that are subject to different mechanisms of regulation. We have exploited the fact that the tryptophanase (tna) operon is induced by tryptophan to infer how tryptophan transport is influenced by the growth medium and by mutations that inactivate each of the permease proteins. In an acid-hydrolyzed casein medium, high levels of tryptophan are ordinarily required to obtain maximum tna operon induction. High levels are necessary because much of the added tryptophan is degraded by tryptophanase. An alternate inducer that is poorly cleaved by tryptophanase, 1-methyltryptophan, induces efficiently at low concentrations in both tna+ strains and tna mutants. In an acid-hydrolyzed casein medium, the TnaB permease is most critical for tryptophan uptake; i.e., only mutations in tnaB reduce tryptophanase induction. However, when 1-methyltryptophan replaces tryptophan as the inducer in this medium, mutations in both mtr and tnaB are required to prevent maximum induction. In this medium, AroP does not contribute to tryptophan uptake. However, in a medium lacking phenylalanine and tyrosine the AroP permease is active in tryptophan transport; under these conditions it is necessary to inactivate the three permeases to eliminate tna operon induction. The Mtr permease is principally responsible for transporting indole, the degradation product of tryptophan produced by tryptophanase action. The TnaB permease is essential for growth on tryptophan as the sole carbon source. When cells with high levels of tryptophanase are transferred to tryptophan-free growth medium, the expression of the tryptophan (trp) operon is elevated. This observation suggests that the tryptophanase present in these cells degrades some of the synthesized tryptophan, thereby creating a mild tryptophan deficiency. Our studies assign roles to

  15. Cathode material for lithium batteries

    Science.gov (United States)

    Park, Sang-Ho; Amine, Khalil

    2013-07-23

    A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

  16. Safety Analysis on Dual-functional Lithium Lead Test Blanket Module With RELAP5%基于 RELAP5的双功能液态锂铅实验包层模块安全分析

    Institute of Scientific and Technical Information of China (English)

    李伟; 田文喜; 秋穗正; 苏光辉

    2013-01-01

    利用嵌入了液态锂铅(LiPb)的热工水力子模块的系统程序RELAP5/MOD3,对双功能液态锂铅(DFLL)实验包层模块(TBM)的安全特性进行评价。对DFLL-TBM 及其辅助冷却系统的稳态运行工况、预期运行事件和相关事故工况进行了建模、计算和分析。计算结果表明,稳态运行时第一壁(FW )结构材料表面最高温度低于允许值550℃。事故工况下氦气泄漏引起的ITER真空室(VV)、窗口设备室(port cell)以及托卡马克冷却水系统大厅拱顶(TCWS vault)的增压均低于ITER要求的限值0.2 MPa。实验包层钢结构不会熔化且可通过辐射换热有效地导出衰变余热。DFLL-TBM 的设计可满足ITER对其热工水力安全方面的要求。%Safety assessment on the dual-functional lithium lead test blanket module (DFLL-TBM) was performed with a modified version of RELAP5/MOD3 code in which the LiPb eutectic thermal-hydraulic sub-module was inserted .The DFLL-TBM and its ancillary cooling systems were modeled to conduct the computation and analysis for steady-state operation ,anticipated operational incidents and relevant accidents .Compu-tational results indicate that the maximum surface temperature of the first wall (FW) structural material is lower than the allowable value of 550 ℃ .For the accident analy-ses ,none of the pressure increases in ITER vacuum vessel (VV) ,port cell and TCWS vault induced by helium leaking is beyond the ITER safety limit of 0.2 MPa .No melting of the TBM box is found and the decay heat can be removed efficiently by the radiation heat transfer .With the current design ,DFLL-TBM can meet the thermal-hydraulic safety requirements from IT ER .

  17. The tryptophan requirements of pullets in the early production stage

    African Journals Online (AJOL)

    cost of 1 kg tryptophan is 20 times the marginal value of 1 kg egg. Under the same ... centration of the diet influence food consumption, the daily amount of amino ..... time spent on correspondence, consultation and analysing the data is highly ...

  18. An immunosuppressive tryptophan-derived alkaloid from Lepidagathis cristata.

    Science.gov (United States)

    Ravikanth, V; Niranjan Reddy, V L; Ramesh, P; Prabhakar Rao, T; Diwan, P V; Khar, A; Venkateswarlu, Y

    2001-12-01

    An immunosuppressive, tryptophan-derived alkaloid cristatin A (1), and two known compounds, cycloartenol and stigmasta-5,11(12)-diene-3 beta-ol, were isolated from the whole plant Lepidagathis cristata Willd. The structures of the isolates were established by interpretation of their spectral data.

  19. Dimeric Complexes of Tryptophan with M2+ Metal Ions

    NARCIS (Netherlands)

    Dunbar, R. C.; Steill, J. D.; Polfer, N. C.; Oomens, J.

    2009-01-01

    IRMPD spectroscopy using the FELIX free electron laser and a Fourier transform ICR mass spectrometer was used to characterize the structures of electrosprayed dimer complexes M(2+)Trp(2) of tryptophan with a series of eight doubly charged metal ions, including alkaline earths Ca, Sr, and Ba, and tra

  20. Preliminary study: voluntary food intake in dogs during tryptophan supplementation.

    Science.gov (United States)

    Fragua, Víctor; González-Ortiz, Gemma; Villaverde, Cecilia; Hervera, Marta; Mariotti, Valentina Maria; Manteca, Xavier; Baucells, María Dolores

    2011-10-01

    Tryptophan, a precursor of important molecules such as serotonin, melatonin and niacin, is an essential amino acid for dogs. In pigs, tryptophan supplementation has been shown to induce a significant increase in food intake. The aim of the present study was to assess whether long-term tryptophan supplementation increases voluntary food intake in dogs and to observe whether this was accompanied by a change in serum ghrelin. In the present study, sixteen adult Beagle dogs were used, with four male and four female dogs fed diets supplemented with tryptophan (1 g/dog per d) during 81 d (Trp) and four male and four female dogs that were not supplemented (control). A voluntary food intake test was performed during 5 d following the supplementation period. The Trp group tended to show a higher food intake during the voluntary food intake test (58.0 (SE 5.37) v. 77.5 (SE 3.65) g/kg metabolic weight per d; P = 0.074). No significant differences were found for serum ghrelin concentrations.

  1. Association between Tryptophan Hydroxylase 2 Gene Polymorphism and Completed Suicide

    Science.gov (United States)

    Fudalej, Sylwia; Ilgen, Mark; Fudalej, Marcin; Kostrzewa, Grazyna; Barry, Kristen; Wojnar, Marcin; Krajewski, Pawel; Blow, Frederic; Ploski, Rafal

    2010-01-01

    The association between suicide and a single nucleotide polymorphism (rs1386483) was examined in the recently identified tryptophan hydroxylase 2 (TPH2) gene. Blood samples of 143 suicide victims and 162 age- and sex-matched controls were examined. The frequency of the TT genotype in the TPH2 polymorphism was higher in suicide victims than in…

  2. Full spectrum millimeter-wave modulation.

    Science.gov (United States)

    Macario, Julien; Yao, Peng; Shi, Shouyuan; Zablocki, Alicia; Harrity, Charles; Martin, Richard D; Schuetz, Christopher A; Prather, Dennis W

    2012-10-01

    In recent years, the development of new lithium niobate electro-optic modulator designs and material processing techniques have contributed to support the increasing need for faster optical networks by considerably extending the operational bandwidth of modulators. In an effort to provide higher bandwidths for future generations of networks, we have developed a lithium niobate electro-optic phase modulator based on a coplanar waveguide ridged structure that operates up to 300 GHz. By thinning the lithium niobate substrate down to less than 39 µm, we are able to eliminate substrate modes and observe optical sidebands over the full millimeter-wave spectrum.

  3. Redox Properties of Tryptophan Metabolism and the Concept of Tryptophan Use in Pregnancy

    Science.gov (United States)

    Xu, Kang; Liu, Hongnan; Bai, Miaomiao; Gao, Jing; Wu, Xin; Yin, Yulong

    2017-01-01

    During pregnancy, tryptophan (Trp) is required for several purposes, and Trp metabolism varies over time in the mother and fetus. Increased oxidative stress (OS) with high metabolic, energy and oxygen demands during normal pregnancy or in pregnancy-associated disorders has been reported. Taking the antioxidant properties of Trp and its metabolites into consideration, we made four hypotheses. First, the use of Trp and its metabolites is optional based on their antioxidant properties during pregnancy. Second, dynamic Trp metabolism is an accommodation mechanism in response to OS. Third, regulation of Trp metabolism could be used to control/attenuate OS according to variations in Trp metabolism during pregnancy. Fourth, OS-mediated injury could be alleviated by regulation of Trp metabolism in pregnancy-associated disorders. Future studies in normal/abnormal pregnancies and in associated disorders should include measurements of free Trp, total Trp, Trp metabolites, and activities of Trp-degrading enzymes in plasma. Abnormal pregnancies and some associated disorders may be associated with disordered Trp metabolism related to OS. Mounting evidence suggests that the investigation of the use of Trp and its metabolites in pregnancy will be meanful. PMID:28737706

  4. Inhibition of Escherichia coli tryptophan indole-lyase by tryptophan homologues.

    Science.gov (United States)

    Do, Quang T; Nguyen, Giang T; Celis, Victor; Phillips, Robert S

    2014-10-15

    We have designed, synthesized and evaluated homotryptophan analogues as possible mechanism-based inhibitors for Escherichia coli tryptophan indole-lyase (tryptophanase, TIL, E.C. 4.1.99.1). As a quinonoid structure is an intermediate in the reaction mechanism of TIL, we anticipated that homologation of the physiological substrate, L-Trp would provide analogues resembling the transition state for β-elimination, and potentially inhibit TIL. Our results demonstrate that L-homotryptophan (1a) is a moderate competitive inhibitor of TIL, with Ki=67 μM, whereas L-bishomotryptophan (1b) displays more potent inhibition, with Ki=4.7 μM. Pre-steady-state kinetics indicated the formation of an external aldimine and quinonoid with 1a, but only the formation of an external aldimine for 1b, suggesting differences in the inhibition mechanism. These results demonstrate that formation of a quinonoid complex is not required for strong inhibition. In addition, the Trp analogues were evaluated as inhibitors of Salmonella typhimurium Trp synthase. Our results indicate that compound 1b is at least 25-fold more selective toward TIL than Trp synthase. We report that compound 1b is comparable to the most potent inhibitor previously reported, while displaying high selectivity for TIL. Thus, 1b is a potential lead for the development of novel antibacterials.

  5. Effect of Tryptophan on the corrosion behavior of low alloy steel in sulfamic acid

    Directory of Open Access Journals (Sweden)

    Hesham T.M. Abdel-Fatah

    2016-11-01

    Full Text Available Sulfamic acid is widely used in various industrial acid cleaning applications. In the present work, the inhibition effect of Tryptophan (Tryp on the corrosion of low alloy steel in sulfamic acid solutions at four different temperatures was studied. The investigations involved electrochemical methods (electrochemical impedance spectroscopy; EIS and the new technique electrochemical frequency modulation; EFM as well as gravimetric measurements. The inhibition efficiency and the apparent activation energy have been calculated in the presence and in the absence of Tryp. It is most probable that the inhibition property of Tryp was due to the electrostatic adsorption of the protonated form of Tryp on the steel surface. Adsorption of the inhibitor molecule, onto the steel surface followed the Temkin adsorption isotherm. The thermodynamic parameters of adsorption were determined and discussed. All of the obtained data from the three techniques were in close agreement, which confirmed that EFM technique can be used efficiently for monitoring the corrosion inhibition under the studied conditions.

  6. Grain Boundary Engineering of Lithium-Ion-Conducting Lithium Lanthanum Titanate for Lithium-Air Batteries

    Science.gov (United States)

    2015-01-01

    Titanate for Lithium-Air Batteries by Victoria L Blair, Claire V Weiss Brennan, and Joseph M Marsico Approved for public...TR-7584 ● JAN 2015 US Army Research Laboratory Grain Boundary Engineering of Lithium-Ion- Conducting Lithium Lanthanum Titanate for Lithium... Titanate for Lithium-Air Batteries 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Victoria L Blair, Claire V

  7. Lithium metal oxide electrodes for lithium batteries

    Science.gov (United States)

    Thackeray, Michael M.; Johnson, Christopher S.; Amine, Khalil; Kang, Sun-Ho

    2010-06-08

    An uncycled preconditioned electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula xLi.sub.2-yH.sub.yO.xM'O.sub.2.(1-x)Li.sub.1-zH.sub.zMO.sub.2 in which 0lithium metal ion with an average trivalent oxidation state selected from two or more of the first row transition metals or lighter metal elements in the periodic table, and M' is one or more ions with an average tetravalent oxidation state selected from the first and second row transition metal elements and Sn. The xLi.sub.2-yH.sub.y.xM'O.sub.2.(1-x)Li.sub.1-zH.sub.zMO.sub.2 material is prepared by preconditioning a precursor lithium metal oxide (i.e., xLi.sub.2M'O.sub.3.(1-x)LiMO.sub.2) with a proton-containing medium with a pH<7.0 containing an inorganic acid. Methods of preparing the electrodes are disclosed, as are electrochemical cells and batteries containing the electrodes.

  8. Lithium literature review: lithium's properties and interactions

    Energy Technology Data Exchange (ETDEWEB)

    Jeppson, D.W.; Ballif, J.L.; Yuan, W.W.; Chou, B.E.

    1978-04-01

    The lithium literature has been reviewed to provide a better understanding of the effects of lithium spills that might occur in magnetic fusion energy (MFE) facilities. Lithium may be used as a breeding blanket and reactor coolant in these facilities. Physical and chemical properties of lithium as well as the chemical interactions of lithium with various gases, metals and non-metals have been identified. A preliminary assessment of lithium-concrete reactions has been completed using differential thermal analysis. Suggestions are given for future studies in areas where literature is lacking or limited.

  9. Consumption of peptide-included and free tryptophan induced by peroxyl radicals: A kinetic study.

    Science.gov (United States)

    Fuentes, E; López-Alarcón, C

    2014-10-01

    It is well-known that tryptophan residues are efficiently oxidized by peroxyl radicals, generating kynurenine, and N-formyl kynurenine as well as hydroperoxide derivatives as products. In the present work we studied the kinetic of such reaction employing free and peptide-included tryptophan. Two azocompounds were used to produce peroxyl radicals: AAPH (2,2'-Azobis(2-methylpropionamidine) dihydrochloride) and ABCVA (4,4'-Azobis(4-cyanovaleric acid)), which generate cationic and anionic peroxyl radicals, respectively. Tryptophan consumption was assessed by fluorescence spectroscopy and the reactions were carried out in phosphate buffer (75mM, pH 7.4) at 45°C. Only a slight effect of the peroxyl radical charge was evidenced on the consumption of free tryptophan and the dipeptide Gly-Trp. Employing AAPH as peroxyl radical source, at low free tryptophan concentrations (1-10µM) near 0.3 mol of tryptophan were consumed per each mol of peroxyl radicals introduced into the system. However, at high free tryptophan concentrations (100µM-1mM) such stoichiometry increased in a tryptophan concentration-way. At 1mM three moles of tryptophan were consumed per mol of AAPH-derived peroxyl radicals, evidencing the presence of chain reactions. A similar behavior was observed when di and tri-peptides (Gly-Trp, Trp-Gly, Gly-Trp-Gly, Trp-Ala, Ala-Trp-Ala) were studied. Nonetheless, at low initial concentration (5µM), the initial consumption rate of tryptophan included in the peptides was two times higher than free tryptophan. In contrast, at high concentration (1mM) free and peptide-included tryptophan showed similar initial consumption rates. These results could be explained considering a disproportionation process of tryptophanyl radicals at low free tryptophan concentrations, a process that would be inhibited when tryptophan is included in peptides.

  10. The Neuroprotective Effect of Lithium in cannabinoid Dependence is Mediated through Modulation of Cyclic AMP, ERK1/2 and GSK-3β Phosphorylation in Cerebellar Granular Neurons of Rat

    Science.gov (United States)

    Rahimi, Hamid Reza; Ghahremani, Mohammad Hossein; Dehpour, Ahmad Reza; Sharifzadeh, Mohammad; Ejtemaei-Mehr, Shahram; Razmi, Ali; Ostad, Seyed Nasser

    2015-01-01

    Lithium (Li), a glycogen synthase kinase-3β (GSK-3β) inhibitor, has used to attenuate the cannabinoid-induced dependence/withdrawal signs, but molecular mechanisms related to this are unclear. Recent studies indicate the involvement of upstream extracellular signal kinase1/2 (ERK1/2) and downstream GSK-3β pathways in the development of cannabinoid-induced dependence. This is mediated through cannabinoid receptor 1 (CB1) enriched in cerebellar granular neurons (CGNs). Accordingly, the present study aimed to investigate the mechanism of modulatory/neuroprotective effects of Li on a cannabinoid agonist (WIN 55,212-2 (WIN))-induced dependence, through quantitative analysis of some involved proteins such as ERK1/2, GSK-3β and related signaling pathways including their phosphorylated forms; and cAMP level as the other molecular mechanisms leading to dependence, in CGNs model. The CGNs were prepared from 7-day-old Wistar rat pup in a 12-well plate, pretreated with Li (1mM) and an ERK1/2 inhibitor SL327 (SL, 10 µM). The WIN (1 µM) was added 30 minutes prior to treatment and AM251 (AM, 1 µM), as a cannabinoid antagonist was co-treated with WIN. The cAMP level, as an indicator of cannabinoid-induced dependence, was measured by ELISA following forskolin (FSK) stimulation. Western blot analyses determined the phosphorylated forms of ERK1/2 (p-ERK1/2), GSK-3β (p-GSK-3β) as well as their total expressions in various treatment times and doses in CGNs. WIN alone could down regulate the cAMP/p-ERK1/2 cascade compared to AM treatment. However, P-GSK-3β was up-regulated with Li and WIN or with SL and Li pretreatment to AM-induced cellular response, which was the highest 60 minutes after CGNs exposure. Results further suggested the potential role of Li pretreatment to diminish the development of cannabinoid-induced dependence/neuronal injury through possible mechanisms of modulating the cAMP/p-ERK1/2 cascade independent of p-GSK-3β signaling pathway in-vitro. PMID:26664379

  11. Lithium Sulfuryl Chloride Battery.

    Science.gov (United States)

    Primary batteries , Electrochemistry, Ionic current, Electrolytes, Cathodes(Electrolytic cell), Anodes(Electrolytic cell), Thionyl chloride ...Phosphorus compounds, Electrical conductivity, Calibration, Solutions(Mixtures), Electrical resistance, Performance tests, Solvents, Lithium compounds

  12. New lithium gas sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Chuntonov, K. [Nanoshell Materials R and D GmbH, Primoschgasse 3, 9020 Klagenfurt (Austria)], E-mail: k.chuntonov@nanoshell.at; Setina, J. [Institute of Metals and Technology, 1000 Ljubljana (Slovenia)

    2008-05-08

    Solid solutions of lithium in Ag and Cu in the form of balls, wires, or strips are convenient sources for depositing lithium films as getters on the walls of vacuum vessels. Measurement of the O{sub 2}, CO and CO{sub 2} sorption characteristics have shown that these films - e.g. those generated electrothermally from Ag/Li solid solutions - excel the best getters of the Ba-film type or the high porosity getters based on Ti, V and Zr alloys. It has been found that tight lithium films passivate as a sorption depth of approximately 100 A is reached. Methods for further improvement of the sorption behavior of lithium coatings are discussed.

  13. Solid-state lithium battery

    Science.gov (United States)

    Ihlefeld, Jon; Clem, Paul G; Edney, Cynthia; Ingersoll, David; Nagasubramanian, Ganesan; Fenton, Kyle Ross

    2014-11-04

    The present invention is directed to a higher power, thin film lithium-ion electrolyte on a metallic substrate, enabling mass-produced solid-state lithium batteries. High-temperature thermodynamic equilibrium processing enables co-firing of oxides and base metals, providing a means to integrate the crystalline, lithium-stable, fast lithium-ion conductor lanthanum lithium tantalate (La.sub.1/3-xLi.sub.3xTaO.sub.3) directly with a thin metal foil current collector appropriate for a lithium-free solid-state battery.

  14. Lithium and Thyroid Disorders

    OpenAIRE

    Lut Tamam; Emel Kulan; Nurgul Ozpoyraz

    2003-01-01

    Lithium is a mood stabilizator drug which has been used in the treatment of many mental disorders including bipolar disorders, cyclothymia, recurrent depression, and schizoaffective disorder for the last 50 years. Clinical and experimental studies have shown that patients under lithium treatment could develop thyroid disorders in a range from single disorder in TSH response to severe mxyedema. [Archives Medical Review Journal 2003; 12(2.000): 99-114

  15. Lithium and Thyroid Disorders

    Directory of Open Access Journals (Sweden)

    Lut Tamam

    2003-04-01

    Full Text Available Lithium is a mood stabilizator drug which has been used in the treatment of many mental disorders including bipolar disorders, cyclothymia, recurrent depression, and schizoaffective disorder for the last 50 years. Clinical and experimental studies have shown that patients under lithium treatment could develop thyroid disorders in a range from single disorder in TSH response to severe mxyedema. [Archives Medical Review Journal 2003; 12(2.000: 99-114

  16. Lithium battery management system

    Science.gov (United States)

    Dougherty, Thomas J [Waukesha, WI

    2012-05-08

    Provided is a system for managing a lithium battery system having a plurality of cells. The battery system comprises a variable-resistance element electrically connected to a cell and located proximate a portion of the cell; and a device for determining, utilizing the variable-resistance element, whether the temperature of the cell has exceeded a predetermined threshold. A method of managing the temperature of a lithium battery system is also included.

  17. Opposing Biological Functions of Tryptophan Catabolizing Enzymes During Intracellular Infection

    Science.gov (United States)

    Divanovic, Senad; Sawtell, Nancy M.; Trompette, Aurelien; Warning, Jamie I.; Dias, Alexandra; Cooper, Andrea M.; Yap, George S.; Arditi, Moshe; Shimada, Kenichi; DuHadaway, James B.; Prendergast, George C.; Basaraba, Randall J.; Mellor, Andrew L.; Munn, David H.; Aliberti, Julio

    2012-01-01

    Recent studies have underscored physiological and pathophysiological roles for the tryptophan-degrading enzyme indolamine 2,3-dioxygenase (IDO) in immune counterregulation. However, IDO was first recognized as an antimicrobial effector, restricting tryptophan availability to Toxoplasma gondii and other pathogens in vitro. The biological relevance of these findings came under question when infectious phenotypes were not forthcoming in IDO-deficient mice. The recent discovery of an IDO homolog, IDO-2, suggested that the issue deserved reexamination. IDO inhibition during murine toxoplasmosis led to 100% mortality, with increased parasite burdens and no evident effects on the immune response. Similar studies revealed a counterregulatory role for IDO during leishmaniasis (restraining effector immune responses and parasite clearance), and no evident role for IDO in herpes simplex virus type 1 (HSV-1) infection. Thus, IDO plays biologically important roles in the host response to diverse intracellular infections, but the dominant nature of this role—antimicrobial or immunoregulatory—is pathogen-specific. PMID:21990421

  18. Archetypal tryptophan-rich antimicrobial peptides: properties and applications.

    Science.gov (United States)

    Shagaghi, Nadin; Palombo, Enzo A; Clayton, Andrew H A; Bhave, Mrinal

    2016-02-01

    Drug-resistant microorganisms ('superbugs') present a serious challenge to the success of antimicrobial treatments. Subsequently, there is a crucial need for novel bio-control agents. Many antimicrobial peptides (AMPs) show a broad-spectrum activity against bacteria, fungi or viruses and are strong candidates to complement or substitute current antimicrobial agents. Some AMPs are also effective against protozoa or cancer cells. The tryptophan (Trp)-rich peptides (TRPs) are a subset of AMPs that display potent antimicrobial activity, credited to the unique biochemical properties of tryptophan that allow it to insert into biological membranes. Further, many Trp-rich AMPs cross bacterial membranes without compromising their integrity and act intracellularly, suggesting interactions with nucleic acids and enzymes. In this work, we overview some archetypal TRPs derived from natural sources, i.e., indolicidin, tritrpticin and lactoferricin, summarising their biochemical properties, structures, antimicrobial activities, mechanistic studies and potential applications.

  19. Structure and Mechanistic Implications of a Tryptophan Synthase Quinonoid Intermediate

    Energy Technology Data Exchange (ETDEWEB)

    Barends,T.; Domratcheva, T.; Kulik, V.; Blumenstein, L.; Niks, D.; Dunn, M.; Schlichting, I.

    2008-01-01

    Quinonoid intermediates play a key role in the catalytic mechanism of pyridoxal 5'-phosphate (PLP)-dependent enzymes. Whereas structures of other PLP-bound reaction intermediates have been determined, a high-quality structure of a quinonoid species has not been reported. We present the crystal structure of the indoline quinonoid intermediate of tryptophan synthase (see figure) and discuss its implications for the enzymatic mechanism and allosteric regulation.

  20. Tryptophan requirements of growing pigs: a dose response study

    NARCIS (Netherlands)

    Vinyeta, E.; Bikker, P.; Corrent, E.; Rovers, M.

    2010-01-01

    A total of 144 pigs were divided into four dietary treatment groups with increasing tryptophan:lysine ratios (apparent ileal digestible (AID) Trp:Lys 0:14, 0:17, 0:20 and 0:23 and standardized ileal digestible (SID) Trp:Lys 0:15, 0:18, 0:21 and 0:24) for 6 weeks. There were 6 replicates with 6

  1. Kinetics of L-tryptophan in depressive patients: a possible correlation between the plasma concentrations of L-tryptophan and some psychiatric rating scales.

    Science.gov (United States)

    Hoes, M J; Loeffen, T; Vree, T B

    1981-01-01

    The plasma concentration and flux of L-tryptophan are abnormal in primary depressive patients, according to the literature. The plasma concentrations of L-tryptophan over a 6-h period after ingestion of 5 g L-tryptophan were investigated and did not differ significantly between depressive patients and controls during the absorption, distribution, and elimination phases. There was no correlation between the plasma concentrations with anxiety or depression scores, or with the excretion in urine of 17-hydroxycorticosteroids and xanthurenic acid during the 24 h after L-tryptophan. Treatment with either 125 mg pyridoxine (three times daily with meals) and L-tryptophan (3 g at 10 PM) or with maprotiline (100 mg at 10 PM) had no influence on the plasma concentrations of L-tryptophan after 2 or 4 weeks of treatment. This excludes L-tryptophan deficiency as a pathogenic factor of depression in the patients studied. No kinetic differences could be demonstrated in the depressive patients, making differences in body compartments or flux of L-tryptophan unlikely to be of pathogenic importance to depression.

  2. Lithium isotope effect accompanying electrochemical intercalation of lithium into graphite

    CERN Document Server

    Yanase, S; Oi, T

    2003-01-01

    Lithium has been electrochemically intercalated from a 1:2 (v/v) mixed solution of ethylene carbonate (EC) and methylethyl carbonate (MEC) containing 1 M LiClO sub 4 into graphite, and the lithium isotope fractionation accompanying the intercalation was observed. The lighter isotope was preferentially fractionated into graphite. The single-stage lithium isotope separation factor ranged from 1.007 to 1.025 at 25 C and depended little on the mole ratio of lithium to carbon of the lithium-graphite intercalation compounds (Li-GIC) formed. The separation factor increased with the relative content of lithium. This dependence seems consistent with the existence of an equilibrium isotope effect between the solvated lithium ion in the EC/MEC electrolyte solution and the lithium in graphite, and with the formation of a solid electrolyte interfaces on graphite at the early stage of intercalation. (orig.)

  3. Hydrogen Outgassing from Lithium Hydride

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, L N; Schildbach, M A; Smith, R A; Balazs1, B; McLean II, W

    2006-04-20

    Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing the measured kinetics to predict hydrogen outgassing as a function of time and temperature are presented. Finally, practical procedures to mitigate the problem of hydrogen outgassing from lithium hydride are discussed.

  4. Concurrent quantification of tryptophan and its major metabolites

    Science.gov (United States)

    Lesniak, Wojciech G.; Jyoti, Amar; Mishra, Manoj K.; Louissaint, Nicolette; Romero, Roberto; Chugani, Diane C.; Kannan, Sujatha; Kannan, Rangaramanujam M.

    2014-01-01

    An imbalance in tryptophan (TRP) metabolites is associated with several neurological and inflammatory disorders. Therefore, analytical methods allowing for simultaneous quantification of TRP and its major metabolites would be highly desirable, and may be valuable as potential biomarkers. We have developed a HPLC method for concurrent quantitative determination of tryptophan, serotonin, 5-hydroxyindoleacetic acid, kynurenine, and kynurenic acid in tissue and fluids. The method utilizes the intrinsic spectroscopic properties of TRP and its metabolites that enable UV absorbance and fluorescence detection by HPLC, without additional labeling. The origin of the peaks related to analytes of interest was confirmed by UV–Vis spectral patterns using a PDA detector and mass spectrometry. The developed methods were validated in rabbit fetal brain and amniotic fluid at gestational day 29. Results are in excellent agreement with those reported in the literature for the same regions. This method allows for rapid quantification of tryptophan and four of its major metabolites concurrently. A change in the relative ratios of these metabolites can provide important insights in predicting the presence and progression of neuroinflammation in disorders such as cerebral palsy, autism, multiple sclerosis, Alzheimer disease, and schizophrenia. PMID:24036037

  5. Comparison of tryptophan interactions to free and grafted BSA protein.

    Science.gov (United States)

    Garnier, F; Randon, J; Rocca, J L

    2000-04-28

    The binding of d- and l-tryptophan molecules to bovine serum albumin (BSA) protein has been studied using liquid chromatography and ultrafiltration in the pH range from 7 to 11. A hydrophobic interaction between tryptophan and BSA has been observed at pH 7.0 on BSA grafted chromatographic column. However, this interaction is negligible at higher pH for which the interaction to the stereospecific site was predominant. For both grafted and free proteins, the complexation mechanism was a competitive binding of d- and l-enantiomers on a single site. The apparent complexation constants for both d- and l-tryptophan show a maximum in the pH range 9-10. The variations of the apparent complexation constants versus pH were the result of the protonation of both the amino acid and a single site of the protein assuming that the complexation occurs between the zwitter-ionic amino acid form and the unprotonated BSA site. The apparent pK(BSA) is slightly shifted from 8.3 for grafted BSA protein to 9.4 for free BSA protein. This shift is presumably as a result of the different protein conformation.

  6. Tryptophan synthase of Phaeophyceae originated from the secondary host nucleus

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yalan; CHI Shan; WU Shuangxiu; LIU Cui; YU Jun; WANG Xumin; CHEN Shengping; LIU Tao

    2014-01-01

    Tryptophan synthase (TS, EC 4.2.1.20) catalyzes the last two steps of L-tryptophan biosynthesis. In pro-karyotes, tryptophan synthase is a multi-enzyme complex, and it consists ofαandβsubunit which forms anα-ββ-αcomplex. In fungi and diatoms, TS is a bifunctional enzyme. Because of the limited genomic and transcriptomic data of algae, there are few studies on TS evolution of algae. Here we analyzed the data of the 1000 Plants Project (1KP), and focused on red algae and brown algae. We found out that the TS of Phaeophy-ceae were fusion genes, which probably originated from the secondary host nucleus, and that the TS of Rho-dophyta contained two genes, TSA and TSB, which both display a possible cyanobacterial origin at the time of primary endosymbiosis. In addition, there were two types of TSB genes (TSB1 and TSB2). Through the multiple sequence alignment of TSB proteins, we found several residues conserved in TSB1 but variable in TSB2 which connect withαsubunit. The phenomenon may suggest that the TSB2 sequences of Rhodophyta cannot form stable complex with TSA.

  7. Tyrosine, phenylalanine, and tryptophan in gastroesophageal malignancy: a systematic review.

    Science.gov (United States)

    Wiggins, Tom; Kumar, Sacheen; Markar, Sheraz R; Antonowicz, Stefan; Hanna, George B

    2015-01-01

    Gastroesophageal cancer has a rapidly increasing incidence worldwide and reliable biomarkers are urgently required to facilitate earlier diagnosis and improve survival. The aromatic amino acids tyrosine, phenylalanine, and tryptophan represent potential biomarkers and their relation to gastroesophageal cancer will be evaluated in this review. An electronic literature search was performed to identify all published research relating to the measurement of tyrosine, phenylalanine, or tryptophan in the biofluids or tissues of patients with gastroesophageal cancer. Sixteen studies were included in this systematic review. Six studies investigated serum concentrations, which all found decreased concentrations of these aromatic amino acids, except one study that found increased phenylalanine. Five studies reported increased concentrations within gastric content of these patients and two reported increased urinary concentrations. Tissue concentrations of these aromatic amino acids were increased in three studies. Tyrosine, phenylalanine, and tryptophan represent potential biomarkers of gastroesophageal cancer, and further research is necessary to definitively establish the mechanism responsible for altered concentrations of these compounds in patients with gastroesophageal cancer.

  8. Nanosensor detection of an immunoregulatory tryptophan influx/kynurenine efflux cycle.

    Science.gov (United States)

    Kaper, Thijs; Looger, Loren L; Takanaga, Hitomi; Platten, Michael; Steinman, Lawrence; Frommer, Wolf B

    2007-10-01

    Mammalian cells rely on cellular uptake of the essential amino acid tryptophan. Tryptophan sequestration by up-regulation of the key enzyme for tryptophan degradation, indoleamine 2,3-dioxygenase (IDO), e.g., in cancer and inflammation, is thought to suppress the immune response via T cell starvation. Additionally, the excreted tryptophan catabolites (kynurenines) induce apoptosis of lymphocytes. Whereas tryptophan transport systems have been identified, the molecular nature of kynurenine export remains unknown. To measure cytosolic tryptophan steady-state levels and flux in real time, we developed genetically encoded fluorescence resonance energy transfer nanosensors (FLIPW). The transport properties detected by FLIPW in KB cells, a human oral cancer cell line, and COS-7 cells implicate LAT1, a transporter that is present in proliferative tissues like cancer, in tryptophan uptake. Importantly, we found that this transport system mediates tryptophan/kynurenine exchange. The tryptophan influx/kynurenine efflux cycle couples tryptophan starvation to elevation of kynurenine serum levels, providing a two-pronged induction of apoptosis in neighboring cells. The strict coupling protects cells that overproduce IDO from kynurenine accumulation. Consequently, this mechanism may contribute to immunosuppression involved in autoimmunity and tumor immune escape.

  9. Nanosensor detection of an immunoregulatory tryptophan influx/kynurenine efflux cycle.

    Directory of Open Access Journals (Sweden)

    Thijs Kaper

    2007-10-01

    Full Text Available Mammalian cells rely on cellular uptake of the essential amino acid tryptophan. Tryptophan sequestration by up-regulation of the key enzyme for tryptophan degradation, indoleamine 2,3-dioxygenase (IDO, e.g., in cancer and inflammation, is thought to suppress the immune response via T cell starvation. Additionally, the excreted tryptophan catabolites (kynurenines induce apoptosis of lymphocytes. Whereas tryptophan transport systems have been identified, the molecular nature of kynurenine export remains unknown. To measure cytosolic tryptophan steady-state levels and flux in real time, we developed genetically encoded fluorescence resonance energy transfer nanosensors (FLIPW. The transport properties detected by FLIPW in KB cells, a human oral cancer cell line, and COS-7 cells implicate LAT1, a transporter that is present in proliferative tissues like cancer, in tryptophan uptake. Importantly, we found that this transport system mediates tryptophan/kynurenine exchange. The tryptophan influx/kynurenine efflux cycle couples tryptophan starvation to elevation of kynurenine serum levels, providing a two-pronged induction of apoptosis in neighboring cells. The strict coupling protects cells that overproduce IDO from kynurenine accumulation. Consequently, this mechanism may contribute to immunosuppression involved in autoimmunity and tumor immune escape.

  10. 5-HT7 receptors and tryptophan hydroxylase in lymphocytes of rats: mitogen activation, physical restraint or treatment with reserpine.

    Science.gov (United States)

    Urbina, Mary; Arroyo, Rubén; Lima, Lucimey

    2014-01-01

    Serotonin (5-HT)7 receptors in lymphocytes play a relevant role as modulators of T cell functions and might be modified by stress protocols. The aims of this work were to evaluate: (i) the presence of 5-HT7 receptors in specific lymphocyte populations, (ii) the probable modifications of them by inflammatory stress with mitogen and (iii) the effects of physical and pharmacological stress. Blood lymphocytes were isolated by density gradients and differential adhesion to plastic. Concanavalin A (Con A) was systemically administered (500 μg/kg) or added to lymphocyte cultures (2.5 μg/ml, final volume 200 μl). Physical restraint was performed in Plexiglass boxes for 5 h per day for 5 days. Reserpine administration was 2.5 mg/kg for 3 days. Immunocytochemical labeling of CD4+, CD8+ and 5-HT7 receptors, and also tryptophan hydroxylase cells was performed. mRNA of 5-HT7 receptors was evaluated by RT-PCR. Controls were included for each protocol. Con A treatment or culture exposure increased the number of lymphocytes expressing 5-HT7 receptors or tryptophan hydroxylase, as compared to absence of the mitogen. Receptors were present in 12-16% of total rat lymphocytes, in ∼10% of CD4+ and in ∼5% of CD8+ cells from control rats. CD4+ decreased, and CD8+ and 5-HT7 cells increased after physical restraint. Reserpine treatment elevated CD8+ and 5-HT7 cells. Con A and physical restraint, but not reserpine treatment, significantly augmented 5-HT7 receptor mRNA in lymphocytes. Rat lymphocytes, expressing tryptophan hydroxylase, could synthesize 5-HT, functioning as a direct autocrine modulator. The modifications of CD4+, CD8+ and 5-HT7 receptors in lymphocytes by three stress protocols could have an impact on immune responses. In addition, the differential distribution of 5-HT7 receptors indicates potential specific physiopathological roles. © 2014 S. Karger AG, Basel.

  11. Lithium Carbonate Modulation of Delayed Rectifier Potassium Channel Involves Protein Kinase C/Mitogen-activated Protein Kinase Signaling in Hippocampus of Rats%碳酸锂通过蛋白激酶C/丝裂原活化蛋白激酶信号调节海马神经元延迟整流钾通道

    Institute of Scientific and Technical Information of China (English)

    焦国慧; 刘朝巍; 张涛; 杨卓

    2008-01-01

    碳酸锂可以用于治疗创伤和神经退行性疾病导致的脑部损伤.研究表明其保护效应与蛋白激酶C(PKC)和胞外信号调节激酶(ERK)有关.研究表明PKC激动剂PDBu可以抑制延迟整流钾通道(IK)电流并使其激活电压曲线向超极化方向移动.碳酸锂(50 μmol/L)可以抑制PDBu的反应.进一步的研究表明,预先加入MEK/ERK抑制剂U0126(20 μmol/L),碳酸锂不能逆转PDBu对,IK的作用.因此,PKC和丝裂原活化蛋白激酶(MAPK)/ERK级联反应通路可能在钾离子通道的磷酸化调节中起作用.另外,AC-cAMP和GC-cGMP的交互作用也可能参与碳酸锂对PKC激活作用的调节,成为其神经保护作用的机制之一.%Lithium carbonate could be used to treat or prevent brain damage following traumatic injury and neurodegenerative diseases.It has been shown that its protective effect is related to protein kinase C (PKC) and extracellular signal-related kinase (ERK).It was demonstrated that PDBu,a PKC activator,inhibited amplitudes of delayed rectifier potassium current (It,) and produced a hyperpolarizing shift in the activation-voltage curve.The responses to PDBu were inhibited by lithium carbonate (50μmol/L).Further studies showed that when pretreated with MEK/ERK inhibitor U0126 (20 μmol/L),although PDBu significantly reduced IK,lithium did not reverse the effect of PDBu.Thus,the results suggested that PKC signaling cascades,along with MAPK (mitogen-activated protein kinase) pathway,were required in the phosphorylation of potassium channel,which was presented by regulation of potassium channel characteristic.AC-cAMP and their eross-talk with GC-cGMP pathway could also modulate the effect of lithium on PKC activation,which could be one of underlying mechanisms likely related to neuroprotective effect of lithium.

  12. Crystal Structure and Mechanism of Tryptophan 2,3-Dioxygenase, a Heme Enzyme Involved in Tryptophan Catabolism and in Quinolinate Biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang,Y.; Kang, S.; Mukherjee, T.; Bale, S.; Crane, B.; Begley, T.; Ealick, S.

    2007-01-01

    The structure of tryptophan 2,3-dioxygenase (TDO) from Ralstonia metallidurans was determined at 2.4 {angstrom}. TDO catalyzes the irreversible oxidation of L-tryptophan to N-formyl kynurenine, which is the initial step in tryptophan catabolism. TDO is a heme-containing enzyme and is highly specific for its substrate L-tryptophan. The structure is a tetramer with a heme cofactor bound at each active site. The monomeric fold, as well as the heme binding site, is similar to that of the large domain of indoleamine 2,3-dioxygenase, an enzyme that catalyzes the same reaction except with a broader substrate tolerance. Modeling of the putative (S)-tryptophan hydroperoxide intermediate into the active site, as well as substrate analogue and mutagenesis studies, are consistent with a Criegee mechanism for the reaction.

  13. A compact self-flowing lithium system for use in an industrial neutron source

    Science.gov (United States)

    Kalathiparambil, Kishor Kumar; Szott, Matthew; Jurczyk, Brian; Ahn, Chisung; Ruzic, David

    2016-10-01

    A compact trench module to flow liquid lithium in closed loops for handling high heat and particle flux have been fabricated and tested at UIUC. The module was designed to demonstrate the proof of concept in utilizing liquid metals for two principal objectives: i) as self-healing low Z plasma facing components, which is expected to solve the issues facing the current high Z components and ii) using flowing lithium as an MeV-level neutron source. A continuously flowing lithium loop ensures a fresh lithium interface and also accommodate a higher concentration of D, enabling advanced D-Li reactions without using any radioactive tritium. Such a system is expected to have a base yield of 10e7 n/s. For both the applications, the key success factor of the module is attaining the necessary high flow velocity of the lithium especially over the impact area, which will be the disruptive plasma events in fusion reactors and the incident ion beam for the neutron beam source. This was achieved by the efficient shaping of the trenches to exploit the nozzle effect in liquid flow. The compactness of the module, which can also be scaled as desired, was fulfilled by the use of high Tc permanent magnets and air cooled channels attained the necessary temperature gradient for driving the lithium. The design considerations and parameters, experimental arrangements involving lithium filling and attaining flow, data and results obtained will be elaborated. DOE SBIR project DE-SC0013861.

  14. Electric batteries. Lithium batteries; Piles electrique. Piles au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Sarrazin, Ch. [Delegation Generale pour l' Armement, DGA/DRET, 75 - Paris (France)

    2002-05-01

    Lithium has the most negative potential and the highest mass capacity of all solid anode materials. It is the metal that allows to reach the highest mass energies in batteries when associated to a high potential cathode. The search for high performance cathodes has led to many different types of lithium batteries (transition metal oxides or sulfides, halogenides, oxi-halogenides, carbon, organic compounds etc..). These batteries can have a solid cathode (Li/CuO, Li/MnO{sub 2}, Li/CF{sub x}, etc..), or a liquid cathode (Li/SOCl{sub 2}, Li/SO{sub 2}, etc..) and in some cases they can have also a solid electrolyte, but not all types of lithium battery led to important industrial fabrication. The increasing use of lithium batteries is linked with the development of portable equipments for which, the compactness of the energy source is a key point. This article examines only the lithium batteries that have been the object of a significant industrial fabrication: lithium-sulfur dioxide, lithium-thionyl chloride, lithium-manganese dioxide, lithium-copper oxide, lithium-carbon fluoride, lithium-iron disulfide, other types of lithium batteries. (J.S.)

  15. Lithium: for harnessing renewable energy

    Science.gov (United States)

    Bradley, Dwight; Jaskula, Brian W.

    2014-01-01

    Lithium, which has the chemical symbol Li and an atomic number of 3, is the first metal in the periodic table. Lithium has many uses, the most prominent being in batteries for cell phones, laptops, and electric and hybrid vehicles. Worldwide sources of lithium are broken down by ore-deposit type as follows: closed-basin brines, 58%; pegmatites and related granites, 26%; lithium-enriched clays, 7%; oilfield brines, 3%; geothermal brines, 3%; and lithium-enriched zeolites, 3% (2013 statistics). There are over 39 million tons of lithium resources worldwide. Of this resource, the USGS estimates there to be approximately 13 million tons of current economically recoverable lithium reserves. To help predict where future lithium supplies might be located, USGS scientists study how and where identified resources are concentrated in the Earth’s crust, and they use that knowledge to assess the likelihood that undiscovered resources also exist.

  16. Tryptophan and its metabolite concentrations in human plasma and breast milk during the perinatal period.

    Directory of Open Access Journals (Sweden)

    Kamimura,Shigehito

    1991-04-01

    Full Text Available Concentrations of tryptophan (free and protein bound and its metabolites in plasma of maternal vein at delivery, umbilical vein, umbilical artery, neonatal vein and breast milk were determined by high performance liquid chromatography. The plasma levels of tryptophan and most of its metabolites in umbilical vein and artery were significantly higher than those in maternal vein. The concentration of total tryptophan in plasma of neonatal vein showed marked decrease at 24 h after birth in comparison with that at birth, but the total kynurenine concentration was not decreased in plasma of neonatal vein. The colostrum contained a high level of total tryptophan. There were high ratios of free to total tryptophan in colostrum, transitional and mature milk. In the blood, ratios of free to total of tryptophan and kynurenine were kept at constant level throughout the perinatal period.

  17. Fatigue in patients with lung cancer is related with accelerated tryptophan breakdown.

    Directory of Open Access Journals (Sweden)

    Katharina Kurz

    Full Text Available BACKGROUND: Patients with cancer often suffer from fatigue and decreased quality of life which might be related to the breakdown of essential amino acid tryptophan. METHODS: In 50 patients with lung cancer we examined fatigue and the deterioration of quality of life in patients using the Functional Assessment of Cancer Therapy Anemia (FACT-An and -Fatigue (FACT-F subscales of FACT-General and the Mental adjustment to Cancer (MAC questionnaires. Results were compared with tryptophan breakdown as well as serum concentrations of immune activation markers. RESULTS: Scores of psychological tests correlated significantly with tryptophan breakdown and with circulatory markers of inflammation. However, immune activation and tryptophan breakdown were not related to MAC scores. CONCLUSIONS: Tryptophan breakdown relates with fatigue and impaired quality of life in patients with lung cancer, while declining tryptophan levels are not associated with patients'coping strategies.

  18. Electrochemical properties of tyrosine phenoxy and tryptophan indolyl radicals in peptides and amino acid analogues

    Energy Technology Data Exchange (ETDEWEB)

    DeFelippis, M.R.; Murthy, C.P.; Klapper, M.H. (Ohio State Univ., Columbus (United States)); Broitman, F.; Weinraub, D.; Faraggi, M. (Nuclear Research Centre-Negev, Beer Sheva (Israel))

    1991-04-18

    Reported here are the redox potentials of the tyrosine phenoxy (tyrO{sup {sm bullet}}) and tryptophan indolyl (trp{sup {sm bullet}}) radicals in peptides containing tyrosine or tryptophan residues. These were determined with pulse radiolysis, and the electrochemical techniques of cyclic voltammetry and differential pulse polarography. The pulse radiolytic and electrochemical methods yield comparable results. There are small differences (relative to the free amino acid) in redox potentials among the different tryptophan and tyrosine containing peptides; in the case of tryptophan these changes may correlate with the position of amino acid in the peptide. The authors also present the redox potentials of some tyrosine and tryptophan derivatives and the acid/base properties of the tryptophan radical cation, when both free and peptide bound.

  19. Lithium nephropathy: a case report

    OpenAIRE

    Raphael Reis Pereira-Silva; Debora Esperancini-Tebar

    2014-01-01

    Although widely used in the management of bipolar disorder, lithium may cause adverse kidney effects. The importance of the present study is to report the case of a 59-year-old woman who was under regular treatment with lithium for bipolar disorder and whose imaging studies demonstrated the presence of multiple renal microcysts, suggesting lithium nephropathy as main diagnostic hypothesis.

  20. Lithium nephropathy: a case report

    Directory of Open Access Journals (Sweden)

    Raphael Reis Pereira-Silva

    2014-01-01

    Full Text Available Although widely used in the management of bipolar disorder, lithium may cause adverse kidney effects. The importance of the present study is to report the case of a 59-year-old woman who was under regular treatment with lithium for bipolar disorder and whose imaging studies demonstrated the presence of multiple renal microcysts, suggesting lithium nephropathy as main diagnostic hypothesis.

  1. Proton transfer in histidine-tryptophan heterodimers embedded in helium droplets

    Energy Technology Data Exchange (ETDEWEB)

    Bellina, Bruno; Merthe, Daniel J.; Kresin, Vitaly V. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States)

    2015-03-21

    We used cold helium droplets as nano-scale reactors to form and ionize, by electron bombardment and charge transfer, aromatic amino acid heterodimers of histidine with tryptophan, methyl-tryptophan, and indole. The molecular interaction occurring through an N–H ⋅ ⋅ ⋅ N hydrogen bond leads to a proton transfer from the indole group of tryptophan to the imidazole group of histidine in a radical cationic environment.

  2. Reaction pathway of tryptophanase-catalyzed L-tryptophan synthesis from D-serine

    OpenAIRE

    Shimada, Akihiko; Ozaki, Haruka; Saito, Takeshi; Fujii, Noriko

    2011-01-01

    Tryptophanase, L-tryptophan indole-lyase with extremely absolute stereospecificity, can change the stereospecificity in concentrated diammonium hydrogenphosphate solution. While tryptophanase is not inert to d-serine in the absence of diammonium hydrogenphosphate, it can undergo L-tryptophan synthesis from d-serine along with indole in the presence of it. It has been well known that tryptophanase synthesizes L-tryptophan from l-serine through a β-substitution mechanism of the ping-pong type. ...

  3. Proton transfer in histidine-tryptophan heterodimers embedded in helium droplets

    CERN Document Server

    Bellina, Bruno; Kresin, Vitaly V

    2015-01-01

    We used cold helium droplets as nano-scale reactors to form and ionize, by electron bombardment and charge transfer, aromatic amino acid heterodimers of histidine with tryptophan, methyl-tryptophan, and indole. The molecular interaction occurring through an N-H...N hydrogen bond leads to a proton transfer from the indole group of tryptophan to the imidazole group of histidine in a radical cationic environment.

  4. Serotonergic function, substance craving, and psychopathology in detoxified alcohol-addicted males undergoing tryptophan depletion.

    Science.gov (United States)

    Wedekind, Dirk; Herchenhein, Thomas; Kirchhainer, Julia; Bandelow, Borwin; Falkai, Peter; Engel, Kirsten; Malchow, Berend; Havemann-Reinecke, Ursula

    2010-12-01

    Alcohol addiction is associated with alterations of central nervous dopaminergic and serotonergic functions. Acute tryptophan depletion has not yet been applied in detoxified alcohol-addicted patients in order to investigate its impact on psychopathology, psychoneuroendocrinology, and substance craving behaviour. 25 alcohol-addicted males randomly either received a tryptophan-free or tryptophan-containing amino acid drink and 7 days later the respective other drink. Anxiety, depression, and craving were assessed before and 5 h after the drink. Tryptophan, 5-HIAA, dopamine, norepinephrine, epinephrine, and HVA in serum were measured before and after both treatments. Nocturnal urinary cortisol measurements and genotyping for the HTTLPR polymorphism of the SLC6A4 gene were performed. Tryptophan depletion resulted in a significant reduction of total and free serum tryptophan while the tryptophan-rich drink increased serum levels. Both treatments caused a significant increase of serum serotonin levels, however, serum 5-HIAA was decreased after depletion but increased after sham depletion. Dopamine and norepinephrine were elevated after tryptophan depletion and sham. Depletion increased depression scores (MADRS), while the full amino acid drink improved state and trait anxiety ratings (STAI) and substance craving. Urinary cortisol excretion was not affected by both treatments. Patients with the ll genotype of the serotonin transporter gene displayed lower baseline tryptophan levels compared to patients with the heterozygous genotype. Results suggest an impaired serotonergic function in alcohol-addicted males.

  5. Circumvention of defective neutral amino acid transport in Hartnup disease using tryptophan ethyl ester.

    Science.gov (United States)

    Jonas, A J; Butler, I J

    1989-07-01

    Tryptophan ethyl ester, a lipid-soluble tryptophan derivative, was used to bypass defective gastrointestinal neutral amino acid transport in a child with Hartnup disease. The child's baseline tryptophan concentrations in serum (20 +/- 6 microM) and cerebrospinal fluid (1.0 +/- 0.2 microM) were persistently less than 50% of normal values. Cerebrospinal fluid 5-hydroxyindoleacetic acid (5-HIAA), a serotonin metabolite, was also less than 50% of normal (21 +/- 2 ng/ml). Serum tryptophan concentrations increased only modestly and briefly after an oral challenge with 200 mg/kg of oral L-tryptophan, reflecting the absorptive defect. An oral challenge with 200 mg/kg of tryptophan ethyl ester resulted in a prompt increase in serum tryptophan to a peak of 555 microM. Sustained treatment with 20 mg/kg q6h resulted in normalization of serum (66 +/- 15 microM) and cerebrospinal fluid tryptophan concentrations (mean = 2.3 microM). Cerebrospinal fluid 5-HIAA increased to more normal concentrations (mean = 33 ng/ml). No toxicity was observed over an 8-mo period of treatment, chronic diarrhea resolved, and body weight, which had remained unchanged for 7 mo before ester therapy, increased by approximately 26%. We concluded that tryptophan ethyl ester is effective at circumventing defective gastrointestinal neutral amino acid transport and may be useful in the treatment of Hartnup disease.

  6. Remarkable Role of Indoleamine 2,3-Dioxygenase and Tryptophan Metabolites in Infectious Diseases: Potential Role in Macrophage-Mediated Inflammatory Diseases

    Directory of Open Access Journals (Sweden)

    Yuki Murakami

    2013-01-01

    Full Text Available Indoleamine 2,3-dioxygenase 1 (IDO1, the L-tryptophan-degrading enzyme, plays a key role in the immunomodulatory effects on several types of immune cells. Originally known for its regulatory function during pregnancy and chronic inflammation in tumorigenesis, the activity of IDO1 seems to modify the inflammatory state of infectious diseases. The pathophysiologic activity of L-tryptophan metabolites, kynurenines, is well recognized. Therefore, an understanding of the regulation of IDO1 and the subsequent biochemical reactions is essential for the design of therapeutic strategies in certain immune diseases. In this paper, current knowledge about the role of IDO1 and its metabolites during various infectious diseases is presented. Particularly, the regulation of type I interferons (IFNs production via IDO1 in virus infection is discussed. This paper offers insights into new therapeutic strategies in the modulation of viral infection and several immune-related disorders.

  7. Dendritic biomimicry: microenvironmental hydrogen-bonding effects on tryptophan fluorescence.

    Science.gov (United States)

    Koenig, S; Müller, L; Smith, D K

    2001-03-02

    Two series of dendritically modified tryptophan derivatives have been synthesised and their emission spectra measured in a range of different solvents. This paper presents the syntheses of these novel dendritic structures and discusses their emission spectra in terms of both solvent and dendritic effects. In the first series of dendrimers, the NH group of the indole ring is available for hydrogen bonding, whilst in the second series, the indole NH group has been converted to NMe. Direct comparison of the emission wavelengths of analogous NH and NMe derivatives indicates the importance of the Kamlet-Taft solvent beta3 parameter, which reflects the ability of the solvent to accept a hydrogen bond from the NH group, an effect not possible for the NMe series of dendrimers. For the NH dendrimers, the attachment of a dendritic shell to the tryptophan subunit leads to a red shift in emission wavelength. This dendritic effect only operates in non-hydrogen-bonding solvents. For the NMe dendrimers, however, the attachment of a dendritic shell has no effect on the emission spectra of the indole ring. This proves the importance of hydrogen bonding between the branched shell and the indole NH group in causing the dendritic effect. This is the first time a dendritic effect has been unambiguously assigned to individual hydrogen-bonding interactions and indicates that such intramolecular interactions are important in dendrimers, just as they are in proteins. Furthermore, this paper sheds light on the use of tryptophan residues as a probe of the microenvironment within proteins--in particular, it stresses the importance of hydrogen bonds formed by the indole NH group.

  8. Dissolution behavior of lithium compounds in ethanol

    Directory of Open Access Journals (Sweden)

    Tomohiro Furukawa

    2016-12-01

    Full Text Available In order to exchange the components which received irradiation damage during the operation at the International Fusion Materials Irradiation Facility, the adhered lithium, which is partially converted to lithium compounds such as lithium oxide and lithium hydroxide, should be removed from the components. In this study, the dissolution experiments of lithium compounds (lithium nitride, lithium hydroxide, and lithium oxide were performed in a candidate solvent, allowing the clarification of time and temperature dependence. Based on the results, a cleaning procedure for adhered lithium on the inner surface of the components was proposed.

  9. Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium-Air Batteries

    Science.gov (United States)

    2014-11-01

    Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium -Air Batteries by Claire Weiss Brennan, Victoria Blair...Ground, MD 21005-5069 ARL-TR-7145 November 2014 Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium -Air...COVERED (From - To) 1 June–31 August 2014 4. TITLE AND SUBTITLE Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium

  10. Quantification of tryptophan in plasma by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Renata Romanholi Pinhati

    2012-01-01

    Full Text Available A simple, rapid and selective method using high-performance liquid chromatography with ultraviolet detection (267 nm was applied for the determination of tryptophan in plasma. Separation was carried out on a C18 column (150 x 4.6 mm internal diameter in 6 min. The mobile phase consisted of 5 mM the sodium acetate and acetonitrile (92:8, v/v. The method was shown to be precise and accurate, and good recovery of analyte was achieved, characterizing the method as efficient and reliable for use in laboratory analysis.

  11. Serotonin synthesis rate and the tryptophan hydroxylase-2

    DEFF Research Database (Denmark)

    Furmark, Tomas; Marteinsdottir, Ina; Frick, Andreas

    2016-01-01

    emission tomography and 5-hydroxy-L-[β -(11)C]tryptophan, [(11)C]5-HTP, a substrate of the second enzymatic step in serotonin synthesis. Parametric images were generated, using the reference Patlak method, and analysed using Statistical Parametric Mapping (SPM8). Blood samples for genotyping of the TPH2 G......-703T polymorphism were obtained from 16 social anxiety disorder patients (T carriers: n=5, GG carriers: n=11). A significantly elevated [(11)C]5-HTP accumulation rate, indicative of enhanced decarboxylase activity and thereby serotonin synthesis capacity, was detected in social anxiety disorder...

  12. Gallium uptake in tryptophan-related pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.M.; Park, C.H.; Intenzo, C.M.; Patel, R. (Thomas Jefferson Univ. Hospital, Philadelphia, PA (USA))

    1991-02-01

    We describe a patient who developed fever, fatigue, muscle weakness, dyspnea, skin rash, and eosinophilia after taking high doses of tryptophan for insomnia for two years. A gallium-67 scan revealed diffuse increased uptake in the lung and no abnormal uptake in the muscular distribution. Bronchoscopy and biopsy confirmed inflammatory reactions with infiltration by eosinophils, mast cells, and lymphocytes. CT scan showed an interstitial alveolar pattern without fibrosis. EMG demonstrated diffuse myopathy. Muscle biopsy from the right thigh showed an inflammatory myositis with eosinophilic and lymphocytic infiltrations.

  13. Lithium Polymer Battery

    Science.gov (United States)

    2003-11-01

    formation of the galvanic cell , lithium foil approximately 150 µm thick and with an area of 0.785 cm2 was placed on top of the pressed electrolyte/cathode...pellet. The entire galvanic cell fabricated in this configuration was hermetically sealed and under pressure. A Tenney environmental chamber was

  14. Tryptophan tryptophylquinone biosynthesis: a radical approach to posttranslational modification.

    Science.gov (United States)

    Davidson, Victor L; Liu, Aimin

    2012-11-01

    Protein-derived cofactors are formed by irreversible covalent posttranslational modification of amino acid residues. An example is tryptophan tryptophylquinone (TTQ) found in the enzyme methylamine dehydrogenase (MADH). TTQ biosynthesis requires the cross-linking of the indole rings of two Trp residues and the insertion of two oxygen atoms onto adjacent carbons of one of the indole rings. The diheme enzyme MauG catalyzes the completion of TTQ within a precursor protein of MADH. The preMADH substrate contains a single hydroxyl group on one of the tryptophans and no crosslink. MauG catalyzes a six-electron oxidation that completes TTQ assembly and generates fully active MADH. These oxidation reactions proceed via a high valent bis-Fe(IV) state in which one heme is present as Fe(IV)=O and the other is Fe(IV) with both axial heme ligands provided by amino acid side chains. The crystal structure of MauG in complex with preMADH revealed that catalysis does not involve direct contact between the hemes of MauG and the protein substrate. Rather it is accomplished through long-range electron transfer, which presumably generates radical intermediates. Kinetic, spectrophotometric, and site-directed mutagenesis studies are beginning to elucidate how the MauG protein controls the reactivity of the hemes and mediates the long range electron/radical transfer required for catalysis. This article is part of a Special Issue entitled: Radical SAM enzymes and Radical Enzymology.

  15. Synthesis and Characterization of Gold Nanoparticles by Tryptophane

    Directory of Open Access Journals (Sweden)

    Azim Akbarzadeh

    2009-01-01

    Full Text Available Problem statement: Preparation and synthesis of gold nanoparticles with small size and suitable stability is very important and applicable particularly in medicine. In this study, we have prepared gold nanoparticles by chemical reduction method employing L-Tryptophane as a reducing agent for ionic gold. Approach: The gold nanoparticles are the most employed amongst the different metallic nanoparticles in the fields of nanomedicine and nanobiotechnology. Therefore, the employed method should provide suitable particle size, shape and particle distribution in order to obtain nanoparticles of high activity and efficiency indicating the importance of the technique. In this study, HAuCl4 .3H2O, L-Tryptophane and polyethyleneglycol (PEG were used to produce AuCl-4 ions. They were acted as pre-material, reducing and stabilizing agents respectively. Results: The size, distribution and formation of gold nanoparticles were confirmed by Transmission Electron Microscopy (TEM indicating the diameter of gold nanoparticles at the range of 10-25 nm and UV spectroscopy. The formed nanoparticles showed the highest absorption at 518 nm. Conclusion: The gold nanoparticles were stable in PEG1000. Since these nanoparticles have suitable size distribution they can be considered as a suitable candidate to be employed in nanomedicine and nanobiotechnology.

  16. The association of sleep quality and insomnia with dietary intake of tryptophan and niacin

    NARCIS (Netherlands)

    Verster, J.; Fernstrand, A.; Bury, D.; Roth, T.; Garssen, J.

    2015-01-01

    Introduction: Dietary intake of tryptophan and niacin have been related to sleep. However, the sleep-promoting effects of these nutrients are still under investigation. The aim of the current study was to examine the relationship between daily dietary intake of tryptophan and niacin and sleep. Mater

  17. Delaying aging and the aging-associated decline in protein homeostasis by inhibition of tryptophan degradation

    NARCIS (Netherlands)

    van der Goot, Annemieke T.; Zhu, Wentao; Vazquez-Manrique, Rafael P.; Seinstra, Renee I.; Dettmer, Katja; Michels, Helen; Farina, Francesca; Krijnen, Jasper; Melki, Ronald; Buijsman, Rogier C.; Silva, Mariana Ruiz; Thijssen, Karen L.; Kema, Ido P.; Neri, Christian; Oefner, Peter J.; Nollen, Ellen A. A.

    2012-01-01

    Toxicity of aggregation-prone proteins is thought to play an important role in aging and age-related neurological diseases like Parkinson and Alzheimer's diseases. Here, we identify tryptophan 2,3-dioxygenase (tdo-2), the first enzyme in the kynurenine pathway of tryptophan degradation, as a metabol

  18. Expression, purification and enzymatic characterization of the catalytic domains of human tryptophan hydroxylase isoforms

    DEFF Research Database (Denmark)

    Windahl, Michael Skovbo; Boesen, Jane; Karlsen, Pernille Efferbach;

    2009-01-01

    Tryptophan hydroxylase exists in two isoforms: Isoform 1 catalyses the first and rate-limiting step in the synthesis of serotonin in the peripheral parts of the body while isoform 2 catalyses this step in the brain. The catalytic domains of human tryptophan hydroxylase 1 and 2 have been expressed...

  19. Tryptophan content for monitoring breast cancer cell aggressiveness by native fluorescence spectroscopy

    Science.gov (United States)

    Zhang, Lin; Pu, Yang; Xue, Jianpeng; Pratavieira, Sebastião.; Xu, Baogang; Achilefu, Samuel; Alfano, R. R.

    2014-03-01

    This study shows tryptophan as the key native marker in cells to determine the level of aggressive cancer in breast cell lines using native fluorescence spectroscopy. An algorithm based on the ratio of tryptophan fluorescence intensity at 340 nm to intensity at 460 nm is associated with aggressiveness of the cancer cells. The higher the ratio is, the more aggressive the tumor towards metastasis.

  20. Self-assembling tryptophan-based designer peptides as intracellular delivery vehicles.

    Science.gov (United States)

    Bhardwaj, Ishanki; Jha, Divya; Admane, Prasad; Panda, Amulya K; Haridas, V

    2016-01-15

    A series of tryptophan-based peptides W1a, b-W4a, b, with diverse architectures were designed and synthesized. These tryptophan containing peptides can self-assemble to spherical particle. This self-assembled system was demonstrated to encapsulate rhodamine B and penetrate the cell membrane.

  1. Growth and decomposition of Lithium and Lithium hydride on Nickel

    DEFF Research Database (Denmark)

    Engbæk, Jakob; Nielsen, Gunver; Nielsen, Jane Hvolbæk

    2006-01-01

    In this paper we have investigated the deposition, structure and decomposition of lithium and lithium-hydride films on a nickel substrate. Using surface sensitive techniques it was possible to quantify the deposited Li amount, and to optimize the deposition procedure for synthesizing lithium......-hydride films. By only making thin films of LiH it is possible to study the stability of these hydride layers and compare it directly with the stability of pure Li without having any transport phenomena or adsorbed oxygen to obscure the results. The desorption of metallic lithium takes place at a lower...... temperature than the decomposition of the lithium-hydride, confirming the high stability and sintering problems of lithium-hydride making the storage potential a challenge. (c) 2006 Elsevier B.V. All rights reserved....

  2. Chiral Discrimination of Tryptophan Enantiomers via (1R, 2R-2-Amino-1, 2-Diphenyl Ethanol Modified Interface

    Directory of Open Access Journals (Sweden)

    Juan Zhou

    2011-01-01

    Full Text Available The paper reported that a simple chiral selective interface constructed by (1R, 2R-2-amino-1, 2-diphenyl ethanol had been developed to discriminate tryptophan enantiomers. Cyclic voltammetry (CV and electrochemical impedance spectroscopy (EIS were used for the characteristic analysis of the electrode. The results indicated that the interface showed stable and sensitive property to determine the tryptophan enantiomers. Moreover, it exhibited the better stereoselectivity for L-tryptophan than that for D-tryptophan. The discrimination characteristics of the chiral selective interface for discriminating tryptophan enantiomers, including the response time, the effect of tryptophan enantiomers concentration, and the stability, were investigated in detail. In addition, the chiral selective interface was used to determine the enantiomeric composition of L- and D-tryptophan enantiomer mixtures by measuring the relative change of the peak current as well as in pure enantiomeric solutions. These results suggested that the chiral selective interface has the potential for enantiomeric discrimination of tryptophan enantiomers.

  3. Enhancement of stability of L-tryptophan dehydrogenase from Nostoc punctiforme ATCC29133 and its application to L-tryptophan assay.

    Science.gov (United States)

    Matsui, Daisuke; Okazaki, Seiji; Matsuda, Motoki; Asano, Yasuhisa

    2015-02-20

    Microbial NAD(+)-dependent L-tryptophan dehydrogenase (TrpDH, EC1.4.1.19), which catalyzes the reversible oxidative deamination and the reductive amination between L-tryptophan and indole-3-pyruvic acid, was found in the scytonemin biosynthetic pathway of Nostoc punctiforme ATCC29133. The TrpDH exhibited high specificity toward L-tryptophan, but its instability was a drawback for L-tryptophan determination. The mutant enzyme TrpDH L59F/D168G/A234D/I296N with thermal stability was obtained by screening of Escherichia coli transformants harboring various mutant genes, which were generated by error-prone PCR using complementation in an L-tryptophan auxotroph of E. coli. The specific activity and stability of this mutant enzyme were higher than those of the wild type enzyme. We also revealed here that in these four mutation points, the two amino acid residues Asp168 and Ile296 contributed to increase the enzyme stability, and the Leu59, Ala234 residues to increase its specific activity. Growth of the strain harboring the gene of above 4 point mutated enzyme was accelerated by the enhanced performance. In the present study, we demonstrated that TrpDH L59F/D168G/A234D/I296N was available for determination of L-tryptophan in human plasma. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Raman microbeam spectrometer noninvasively measures biomoelcules to monitor the tryptophan metabolic pathway

    Science.gov (United States)

    Michel, Gregory; Bigelow, Alan W.; Harden, Jamie; Krueger, James G.; Gareau, Daniel S.

    2014-03-01

    Toward improving early detection of melanoma by accurate diagnosis and avoidance of unnecessary surgical excisions of common moles, we are developing noninvasive quantitative spectral fingerprinting of protein expression using Raman spectroscopy within confocally gated volumes of tissue. Our first target is the L-tryptophan catabolism pathway, which is unregulated in the tumor micro-environment and inhibits the immune response that usually is tumor suppressive. The tryptophan pathway is therefore worthy of diagnostic measurement and finding the ratio of L-tryptophan to its metabolites may aid a melanoma diagnosis. We report the intensity of the Raman signal from L-tryptophan and quinolinic acid, which are found during different stages of the tryptophan metabolic pathway.

  5. Correlation of tryptophan fluorescence intensity decay parameters with sup 1 H NMR-determined rotamer conformations: (tryptophan sup 2 )oxytocin

    Energy Technology Data Exchange (ETDEWEB)

    Ross, J.B.A.; Schwartz, G.P.; Laws, W.R. (Mount Sinai, New York, NY (United States)); Wyssbrod, H.R.; Porter, R.A. (Univ. of Louisville, KY (United States)); Michaels, C.A. (Swarthmore Coll., PA (United States))

    1992-02-18

    While the fluorescence decay kinetics of tyrosine model compounds can be explained in terms of heterogeneity derived from the three ground-state {chi}{sup 1} rotamers, a similar correlation has yet to be directly observed for a tryptophan residue. In addition, the asymmetric indole ring might also lead to heterogeneity from {chi}{sup 2} rotations. In this paper, the time-resolved and steady-state fluorescence properties of (tryptophan{sup 2})oxytocin at pH 3 are presented and compared with {sup 1}H NMR results. According to the unrestricted analyses of individual fluorescence decay curves taken as a function of emission wavelength-independent decay constants, only three exponential terms are required. In addition, the preexponential weighting factors (amplitudes) have the same relative relationship (weights) as the {sup 1}H NMR-determined {chi}{sup 1} rotamer populations of the indole side chain. {sup 15}N was used in heteronuclear coupling experiments to confirm the rotamer assignments. Inclusion of a linked function restricting the decay amplitudes to the {chi}{sup 1} rotamer populations in the individual decay curve analyses and in the global analysis confirms this correlation. According to qualitative nuclear Overhauser data, there are two {chi}{sup 2} populations.

  6. Agmatine enhances the antidepressant-like effect of lithium in mouse forced swimming test through NMDA pathway.

    Science.gov (United States)

    Mohseni, Gholmreza; Ostadhadi, Sattar; Imran-Khan, Muhammad; Norouzi-Javidan, Abbas; Zolfaghari, Samira; Haddadi, Nazgol-Sadat; Dehpour, Ahmad-Reza

    2017-04-01

    Depression is one the world leading global burdens leading to various comorbidities. Lithium as a mainstay in the treatment of depression is still considered gold standard treatment. Similar to lithium another agent agmatine has also central protective role against depression. Since, both agmatine and lithium modulate various effects through interaction with NMDA receptor, therefore, in current study we aimed to investigate the synergistic antidepressant-like effect of agmatine with lithium in mouse force swimming test. Also to know whether if such effect is due to interaction with NMDA receptor. In our present study we found that when potent dose of lithium (30mg/kg) was administered, it significantly decreased the immobility time. Also, when subeffective dose of agmatine (0.01mg/kg) was coadministered with subeffective dose of lithium (3mg/kg), it potentiated the antidepressant-like effect of subeffective dose of lithium. For the involvement of NMDA receptor in such effect, we administered NMDA receptor antagonist MK-801 (0.05mg/kg) with a combination of subeffective dose of lithium (3mg/kg) and agmatine (0.001mg/kg). A significant antidepressant-like effect was observed. Furthermore, when subeffective dose (50 and 75mg/kg) of NMDA was given it inhibited the synergistic effect of agmatine (0.01mg/kg) with lithium (3mg/kg). Hence, our finding demonstrate that agmatine have synergistic effect with lithium which is mediated by NMDA receptor pathway.

  7. Lithium clearance in chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

    1989-01-01

    1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption...... of lithium or influence of osmotic diuresis. 3. Fractional reabsorption of lithium was reduced in most patients with glomerular filtration rates below 25 ml/min. 4. Calculated fractional distal reabsorption of sodium was reduced in most patients with glomerular filtration rates below 50 ml/min. 5. Lithium...... that lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

  8. Experimental lithium system. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kolowith, R.; Berg, J.D.; Miller, W.C.

    1985-04-01

    A full-scale mockup of the Fusion Materials Irradiation Test (FMIT) Facility lithium system was built at the Hanford Engineering Development Laboratory (HEDL). This isothermal mockup, called the Experimental Lithium System (ELS), was prototypic of FMIT, excluding the accelerator and dump heat exchanger. This 3.8 m/sup 3/ lithium test loop achieved over 16,000 hours of safe and reliable operation. An extensive test program demonstrated satisfactory performance of the system components, including the HEDL-supplied electromagnetic lithium pump, the lithium jet target, the purification and characterization hardware, as well as the auxiliary argon and vacuum systems. Experience with the test loop provided important information on system operation, performance, and reliability. This report presents a complete overview of the entire Experimental Lithium System test program and also includes a summary of such areas as instrumentation, coolant chemistry, vapor/aerosol transport, and corrosion.

  9. Rapid reversal by naloxone of the chronic effects of morphine on rat liver and brain tryptophan metabolism.

    OpenAIRE

    Badawy, A. A.; Evans, M.

    1981-01-01

    The chronic morphine-induced inhibition of rat liver tryptophan pyrrolase activity and the resultant increases in tryptophan availability to the brain and brain 5-hydroxytryptamine (5-HT) synthesis are reversed within 10 min after naloxone administration. The possible involvement of hepatic tryptophan metabolism in morphine dependence is briefly discussed.

  10. Separators for Lithium Ion Batteries

    Institute of Scientific and Technical Information of China (English)

    G.C.Li; H.P.Zhang; Y.P.Wu

    2007-01-01

    1 Results A separator for rechargeable batteries is a microporous membrane placed between electrodes of opposite polarity, keeping them apart to prevent electrical short circuits and at the same time allowing rapid transport of lithium ions that are needed to complete the circuit during the passage of current in an electrochemical cell, and thus plays a key role in determining the performance of the lithium ion battery. Here provides a comprehensive overview of various types of separators for lithium io...

  11. Lithium-Associated Kidney Microcysts

    OpenAIRE

    Jennifer Tuazon; David Casalino; Ehteshamuddin Syed; Daniel Batlle

    2008-01-01

    Long-term lithium therapy is associated with impairment in concentrating ability and, occasionally, progression to advanced chronic kidney disease from tubulointerstitial nephropathy. Biopsy findings in patients with lithium-induced chronic tubulointerstitial nephropathy include tubular atrophy and interstitial fibrosis interspersed with tubular cysts and dilatations. Recent studies have shown that cysts are seen in 33––62.5% of the patients undergoing lithium therapy. MR imaging is highly ca...

  12. Membranes in Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Junbo Hou

    2012-07-01

    Full Text Available Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed.

  13. Membranes in lithium ion batteries.

    Science.gov (United States)

    Yang, Min; Hou, Junbo

    2012-07-04

    Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed.

  14. The liquid lithium limiter control system on FTU

    Energy Technology Data Exchange (ETDEWEB)

    Bertocchi, A. [EURATOM-ENEA Association, Frascati Research Center, Via E. Fermi 45, 00044 Frascati (Rome) (Italy)], E-mail: bertocchi@frascati.enea.it; Di Donna, M. [Department of Informatics, Systems and Productions, University of Rome Tor Vergata, Rome (Italy); Panella, M.; Vitale, V. [EURATOM-ENEA Association, Frascati Research Center, Via E. Fermi 45, 00044 Frascati (Rome) (Italy)

    2007-10-15

    In the second half of 2005, a liquid lithium limiter (LLL) with capillary porous system (CPS) configuration was installed to test on Tokamak FTU. The liquid lithium flows through capillaries from a reservoir to the side faced to the plasma to form a thin lithium film as wall coating. The system includes three stainless steel cases, which contain two thermocouples each one. A heating system brings the Li temperature about 200 deg. C to allow the liquid to flow. This temperature, monitored by thermocouples, needs to be controlled. To carry out this experimental procedure, some new features have been introduced in the existent control system based on Opto22{sup TM} modules and a CORBA/PHP/MySQL software architecture. The historical data storage to keep the lithium temperature evolution has been added. Two graphical tools - developed in MATLAB{sup TM} and Java environments, respectively, to monitor the lithium temperature coming from thermocouples - have been also implemented. The LLL control system allows to regulate the heater temperature in each unit to reach operational conditions, where the temperature adjustment can be performed either automatically through a specific control law or manually by the operator. During the plasma shot the system switches off the limiter power supply to prevent instruments damage. Moreover, in the same experimental context, a first approach to automatically obtain executable code - starting from control laws designed by Simulink{sup TM} tool - has been realized.

  15. Investigation of tin-lithium eutectic as a liquid plasma facing material

    Science.gov (United States)

    Ruzic, David; Szott, Matthew; Christenson, Michael; Shchelkanov, Ivan; Kalathiparambil, Kishor Kumar

    2016-10-01

    Innovative materials and techniques need to be utilized to address the high heat and particle flux incident on plasma facing components in fusion reactors. A liquid metal diverter module developed at UIUC with self circulating lithium has been successfully demonstrated to be capable of handling the relevant heat flux in plasma gun based tests and on operational tokamaks. The proper geometry of the liquid lithium trenches to minimize droplet ejection during transient plasma events have also been identified. Although lithium has proven to be effective in improved plasma performance and contributes to other advantageous factors like reduction in the fuel recycling, impurity gettering and, owing to the low Z, a significantly reduced impact on plasma as compared to the solid wall materials, it still poses several drawbacks related to its high reactivity and high vapor pressure at the relevant tokamak wall temperatures. The evaporation properties of a new eutectic mixture of tin and lithium (20% Sn) shows that lithium segregates to the surface at melting temperatures and hence is an effective replacement for pure lithium. Also, the vapor from the eutectic is dominated by lithium, minimizing the entry of high Z Sn into the plasma. At UIUC experiments for the synthesis and characterization of the eutectic - measurement of the critical wetting parameters and Seebeck coefficients with respect to the trench materials have been performed to ensure lithium wetting and flow in the trenches. The results will be presented. DOE project DEFG02- 99ER54515.

  16. Lithium excessively enhances event related beta oscillations in patients with bipolar disorder.

    Science.gov (United States)

    Atagün, Murat İlhan; Güntekin, Bahar; Tan, Devran; Tülay, Emine Elif; Başar, Erol

    2015-01-01

    Previous resting-state electroencephalography studies have consistently shown that lithium enhances delta and theta oscillations in default mode networks. Cognitive task based networks differ from resting-state networks and this is the first study to investigate effects of lithium on evoked and event-related beta oscillatory responses of patients with bipolar disorder. The study included 16 euthymic patients with bipolar disorder on lithium monotherapy, 22 euthymic medication-free patients with bipolar disorder and 21 healthy participants. The maximum peak-to-peak amplitudes were measured for each subject's averaged beta responses (14-28 Hz) in the 0-300 ms time window. Auditory simple and oddball paradigm were presented to obtain evoked and event-related beta oscillatory responses. There were significant differences in beta oscillatory responses between groups (p=0.010). Repeated measures ANOVA revealed location (p=0.007), laterality X group (p=0.043) and stimulus X location (p=0.013) type effects. Serum lithium levels were correlated with beta responses. The lithium group had higher number of previous episodes, suggesting that patients of the lithium were more severe cases than patients of the medication-free group. Lithium stimulates neuroplastic cascades and beta oscillations become prominent during neuroplastic changes. Excessively enhanced beta oscillatory responses in the lithium-treated patients may be indicative of excessive activation of the neuron groups of the certain cognitive networks and dysfunctional GABAergic modulation during cognitive activity. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Chemical Modification and Fluorescence Spectrum of Tryptophan Residues in Pullulanase

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Tryptophan(Trp) residues in a pullulanase were modified by N-bromosuccinimide(NBS). The results of the Spande method indicate that there are 18 Trp residues in the pullulanase and nine of them are located on the surface of the enzyme. Three of these Trp residues are nonessential residues which show the fastest reaction rate according to the Zou′s plot. Two of the seven relative faster reacting residues are essential for the activity of the enzyme. The other eight are the slowest in the reaction rate or non-reactive residues for the reaction. The fluorescence and circular dichroism(CD) spectra of the pullulanase have been changed after the reaction with NBS. Potassium iodide(KI) and acrylamide also have remarkable influences on the fluorescence spectra of the pullulanase.

  18. Tryptophan, Neurodegeneration and HIV-Associated Neurocognitive Disorder

    Directory of Open Access Journals (Sweden)

    Nicholas W.S. Davies

    2010-06-01

    Full Text Available This review presents an up-to-date assessment of the role of the tryptophan metabolic and catabolic pathways in neurodegenerative disease and HIV-associated neurocognitive disorder. The kynurenine pathway and the effects of each of its enzymes and products are reviewed. The differential expression of the kynurenine pathway in cells within the brain, including inflammatory cells, is explored given the increasing recognition of the importance of inflammation in neurodegenerative disease. An overview of common mechanisms of neurodegeneration is presented before a review and discussion of the evidence for a pathogenetic role of the kynurenine pathway in Alzheimer’s disease, HIV-associated neurocognitive disorder, Huntington’s disease, motor neurone disease, and Parkinson’s disease.

  19. Doxycycline induced photodamage to human neutrophils and tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, S.; Glette, J.; Hopen, G.; Solberg, C.O. (Haukeland Sykehus, Bergen (Norway))

    1984-01-01

    Neutrophil function were studied following irradiation (340-380 nm) of the cells in the presence of 22 ..mu..M doxycycline. At increasing light fluence the locomotion, chemiluminescence and glucose oxidation (by the hexose monophosphate shunt) of the neutrophils steadily decreased. The photodamage increased with increasing preincubation temperature and time and was enhanced in D/sub 2/O, reduced in azide and abolished in anaerobiosis. Superoxide dismutase, catalase or mannitol did not influence the photodamage. Photooxidation of tryptophan in the presence of doxycycline was increased 9-10-fold in D/sub 2/O and nearly abolished in the presence of 0.25 mM NaN/sub 3/, indicating that singlet oxygen is the most important reactive oxygen species in the doxycycline-induced photodamage. The results may explain some of the features of tetracycline-induced photosensitivity and why other authors have obtained diverging results when studying the influence of tetracyclines on neutrophil functions.

  20. A Relay Pathway between Arginine and Tryptophan Metabolism Confers Immunosuppressive Properties on Dendritic Cells.

    Science.gov (United States)

    Mondanelli, Giada; Bianchi, Roberta; Pallotta, Maria Teresa; Orabona, Ciriana; Albini, Elisa; Iacono, Alberta; Belladonna, Maria Laura; Vacca, Carmine; Fallarino, Francesca; Macchiarulo, Antonio; Ugel, Stefano; Bronte, Vincenzo; Gevi, Federica; Zolla, Lello; Verhaar, Auke; Peppelenbosch, Maikel; Mazza, Emilia Maria Cristina; Bicciato, Silvio; Laouar, Yasmina; Santambrogio, Laura; Puccetti, Paolo; Volpi, Claudia; Grohmann, Ursula

    2017-02-21

    Arginase 1 (Arg1) and indoleamine 2,3-dioxygenase 1 (IDO1) are immunoregulatory enzymes catalyzing the degradation of l-arginine and l-tryptophan, respectively, resulting in local amino acid deprivation. In addition, unlike Arg1, IDO1 is also endowed with non-enzymatic signaling activity in dendritic cells (DCs). Despite considerable knowledge of their individual biology, no integrated functions of Arg1 and IDO1 have been reported yet. We found that IDO1 phosphorylation and consequent activation of IDO1 signaling in DCs was strictly dependent on prior expression of Arg1 and Arg1-dependent production of polyamines. Polyamines, either produced by DCs or released by bystander Arg1(+) myeloid-derived suppressor cells, conditioned DCs toward an IDO1-dependent, immunosuppressive phenotype via activation of the Src kinase, which has IDO1-phosphorylating activity. Thus our data indicate that Arg1 and IDO1 are linked by an entwined pathway in immunometabolism and that their joint modulation could represent an important target for effective immunotherapy in several disease settings.

  1. Optimization strategies in the modelling of SG-SMB applied to separation of phenylalanine and tryptophan

    Science.gov (United States)

    Diógenes Tavares Câmara, Leôncio

    2014-03-01

    The solvent-gradient simulated moving bed process (SG-SMB) is the new tendency in the performance improvement if compared to the traditional isocratic solvent conditions. In such SG-SMB process the modulation of the solvent strength leads to significant increase in the purities and productivity followed by reduction in the solvent consumption. A stepwise modelling approach was utilized in the representation of the interconnected chromatographic columns of the system combined with a lumped mass transfer model between the solid and liquid phase. The influence of the solvent modifier was considered applying the Abel model which takes into account the effect of modifier volume fraction over the partition coefficient. Correlation models of the mass transfer parameters were obtained through the retention times of the solutes according to the volume fraction of modifier. The modelling and simulations were carried out and compared to the experimental SG-SMB separation unit of the amino acids Phenylalanine and Tryptophan. The simulation results showed the great potential of the proposed modelling approach in the representation of such complex systems. The simulations showed great agreement fitting the experimental data of the amino acids concentrations both at the extract as well as at the raffinate. A new optimization strategy was proposed in the determination of the best operating conditions which uses the phi-plot concept.

  2. Nocturnal plasma levels of melatonin in quails (Coturnix japonica injected with l-5-hydroxy-tryptophan

    Directory of Open Access Journals (Sweden)

    LC. Reis

    Full Text Available This study aimed to demonstrate the influence of the systemic administration of l-5-hydroxy-tryptophan (L-HTP on the plasma levels of melatonin during the dark period in quails. Throughout daylight, the plasma levels of melatonin did not differ significantly, oscillating between 110.2 ± 15.8 pg.mL-1 and 157.4 ± 34.8 pg.mL-1, from 8 to 16 hours. L-HTP (25 mg.kg-1, through the intracelomic route administered at 18 hours lessened significantly the nocturnal increase of the plasma levels of melatonin (controls, 327.3 ± 20.1 and 315.8 ± 20.9 pg.mL-1 vs. 242.1 ± 24.8 and 217.5 ± 21 pg.mL-1, respectively, at 20 and 24 hours, P < 0.05. The results obtained showed that the administration of LHTP reduced the nocturnal melatonin release, possibly by bringing about an increase in serotonin synthesis and synaptic release in the pineal. Therefore, the serotoninergic transmission from the raphe towards the pineal would constitute a mechanism of modulation of the synthesis and melatonin release in quails.

  3. New lithium gas sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Chuntonov, K. [NanoShell Consulting, Zalman Shneour 16, 32544 Haifa (Israel)], E-mail: konstantin@chuntonov.com; Ivanov, A.; Permikin, D. [Ural State University, Lenin Avenue 51, 620083 Ekaterinburg (Russian Federation)

    2009-03-05

    A theory of gas sorption by lithium solid solutions, which is based on a simple diffusion model, has been applied to the processes of gettering residual gases in small sealed-off chambers of a MEMS-cavity type. The analysis of kinetics of the process leads to the conclusion that under certain conditions, which are formulated in the form of a criterial inequality G > 1, there is no further need of outside means for pumping down the microchambers before sealing-off. A vacuum inside the microchamber is created and further maintained for a long time at a constant level due to gas sorption by the getter material itself. The huge sorption capacity of lithium solid solutions is able to increase the lifetime of evacuated MEMS devices by more than one order of magnitude and to extend it to 20 years.

  4. Lithium - induced tardive dystonia.

    Directory of Open Access Journals (Sweden)

    Chakrabarti S

    2002-10-01

    Full Text Available Tardive dystonia is an uncommon form of chronic dystonia, which usually develops on exposure to neuroleptics. Tardive dystonia (Tdt following lithium therapy has not been previously reported. The case of 38 year old man with bipolar affective disorder who developed tardive dystonia while on maintenance lithium treatment is described. Presentation of Tdt in this patient was fairly characteristic although there was no suggestion of recent neuroleptic exposure. Tdt known to have poor treatment response, responded very well to clozapine, a novel anti-psychotic, in this case. To conclude, Tdt may develop on exposure to drugs other than neuroleptics. An adequate trial to clozapine can prove to be a useful treatment option.

  5. Defective tryptophan catabolism underlies inflammation in mouse chronic granulomatous disease.

    Science.gov (United States)

    Romani, Luigina; Fallarino, Francesca; De Luca, Antonella; Montagnoli, Claudia; D'Angelo, Carmen; Zelante, Teresa; Vacca, Carmine; Bistoni, Francesco; Fioretti, Maria C; Grohmann, Ursula; Segal, Brahm H; Puccetti, Paolo

    2008-01-10

    Half a century ago, chronic granulomatous disease (CGD) was first described as a disease fatally affecting the ability of children to survive infections. Various milestone discoveries have since been made, from an insufficient ability of patients' leucocytes to kill microbes to the underlying genetic abnormalities. In this inherited disorder, phagocytes lack NADPH oxidase activity and do not generate reactive oxygen species, most notably superoxide anion, causing recurrent bacterial and fungal infections. Patients with CGD also suffer from chronic inflammatory conditions, most prominently granuloma formation in hollow viscera. The precise mechanisms of the increased microbial pathogenicity have been unclear, and more so the reasons for the exaggerated inflammatory response. Here we show that a superoxide-dependent step in tryptophan metabolism along the kynurenine pathway is blocked in CGD mice with lethal pulmonary aspergillosis, leading to unrestrained Vgamma1(+) gammadelta T-cell reactivity, dominant production of interleukin (IL)-17, defective regulatory T-cell activity and acute inflammatory lung injury. Although beneficial effects are induced by IL-17 neutralization or gammadelta T-cell contraction, complete cure and reversal of the hyperinflammatory phenotype are achieved by replacement therapy with a natural kynurenine distal to the blockade in the pathway. Effective therapy, which includes co-administration of recombinant interferon-gamma (IFN-gamma), restores production of downstream immunoactive metabolites and enables the emergence of regulatory Vgamma4(+) gammadelta and Foxp3(+) alphabeta T cells. Therefore, paradoxically, the lack of reactive oxygen species contributes to the hyperinflammatory phenotype associated with NADPH oxidase deficiencies, through a dysfunctional kynurenine pathway of tryptophan catabolism. Yet, this condition can be reverted by reactivating the pathway downstream of the superoxide-dependent step.

  6. Biochemistry of primary headaches: role of tyrosine and tryptophan metabolism.

    Science.gov (United States)

    D'Andrea, G; Cevoli, S; Colavito, D; Leon, A

    2015-05-01

    The pathogenesis of migraine as well as cluster headache (CH) is yet a debated question. In this review, we discuss the possible role of the of tyrosine and tryptophan metabolism in the pathogenesis of these primary headaches. These include the abnormalities in the synthesis of neurotransmitters: high level of DA, low level of NE and very elevated levels of octopamine and synephrine (neuromodulators) in plasma of episodic migraine without aura and CH patients. We hypothesize that the imbalance between the levels of neurotransmitters and elusive amines synthesis is due to a metabolic shift directing tyrosine toward an increased decarboxylase and reduced hydroxylase enzyme activities. The metabolic shift of the tyrosine is favored by a state of neuronal hyperexcitability and a reduced mitochondrial activity present in migraine. In addition we present biochemical studies performed in chronic migraine and chronic tension-type headache patients to verify if the same anomalies of the tyrosine and tryptophan metabolism are present in these primary headaches and, if so, their possible role in the chronicity process of CM and CTTH. The results show that important abnormalities of tyrosine metabolism are present only in CM patients (very high plasma levels of DA, NE and tryptamine). Tryptamine plasma levels were found significantly lower in both CM and CTTH patients. In view of this, we propose that migraine and, possibly, CH attacks derive from neurotransmitter and neuromodulator metabolic abnormalities in a hyperexcitable and hypoenergetic brain that spread from the frontal lobe, downstream, resulting in abnormally activated nuclei of the pain matrix. The low tryptamine plasma levels found in CM and CTTH patients suggest that these two primary chronic headaches are characterized by a common insufficient serotoninergic control of the pain threshold.

  7. Optimized lithium oxyhalide cells

    Science.gov (United States)

    Kilroy, W. P.; Schlaikjer, C.; Polsonetti, P.; Jones, M.

    1993-04-01

    Lithium thionyl chloride cells were optimized with respect to electrolyte and carbon cathode composition. Wound 'C-size' cells with various mixtures of Chevron acetylene black with Ketjenblack EC-300J and containing various concentrations of LiAlCl4 and derivatives, LiGaCl4, and mixtures of SOCl2 and SO2Cl2 were evaluated as a function of discharge rate, temperature, and storage condition.

  8. New lithium gas sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Chuntonov, K. [Nanoshell Materials R and D GmbH, Primoschgasse 3, 9020 Klagenfurt (Austria)], E-mail: konstantin@chuntonov.com; Setina, J. [Institute of Metals and Technology, 1000 Ljubljana (Slovenia); Ivanov, A.; Permikin, D. [Ural State University, Lenin Avenue 51, 620083 Ekaterinburg (Russian Federation)

    2008-07-28

    The kinetics of lithium evaporation from Ag-Li wire has been studied experimentally in the temperature interval 520-630 deg. C. The initial stage of the process takes place in the kinetic regime and finishes with the formation of a thin layer of silver on the surface of the alloy. Then the process moves to the diffusion region where the evaporation flow and the mass of the deposited film can be described quantitatively with the help of simple analytical expressions.

  9. Lithium ion sources

    Science.gov (United States)

    Roy, Prabir K.; Greenway, Wayne G.; Grote, Dave P.; Kwan, Joe W.; Lidia, Steven M.; Seidl, Peter A.; Waldron, William L.

    2014-01-01

    A 10.9 cm diameter lithium alumino-silicate ion source has been chosen as a source of ˜100mA lithium ion current for the Neutralized Drift Compression Experiment (NDCX-II) at LBNL. Research and development was carried out on lithium alumino-silicate ion sources prior to NDCX-II source fabrication. Space-charge-limited emission with the current density exceeding 1 mA/cm2 was measured with 0.64 cm diameter lithium alumino-silicate ion sources at 1275 °C. The beam current density is less for the first 10.9 cm diameter NDCX-II source, and it may be due to an issue of surface coverage. The lifetime of a thin coated (on a tungsten substrate) source is varied, roughly 40-50 h, when pulsed at 0.05 Hz and with pulse length of 6μs each, i.e., a duty factor of 3×10-7, at an operating temperature of 1250-1275 °C. The 10.9 cm diameter source lifetime is likely the same as of a 0.64 cm source, but the lifetime of a source with a 2 mm diameter (without a tungsten substrate) is 10-15 h with a duty factor of 1 (DC extraction). The lifetime variation is dependent on the amount of deposition of β-eucryptite mass, and the surface temperature. The amount of mass deposition does not significantly alter the current density. More ion source work is needed to improve the large source performance.

  10. Lithium ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Prabir K., E-mail: pkroy@lbl.gov [Lawrence Berkeley National Laboratory (LBNL), One Cyclotron Road, Berkeley, California CA-94720 (United States); Greenway, Wayne G. [Lawrence Berkeley National Laboratory (LBNL), One Cyclotron Road, Berkeley, California CA-94720 (United States); Grote, Dave P. [Lawrence Livermore National Laboratory LLC, CA-94550 (United States); Kwan, Joe W.; Lidia, Steven M.; Seidl, Peter A.; Waldron, William L. [Lawrence Berkeley National Laboratory (LBNL), One Cyclotron Road, Berkeley, California CA-94720 (United States)

    2014-01-01

    A 10.9 cm diameter lithium alumino-silicate ion source has been chosen as a source of ∼100mA lithium ion current for the Neutralized Drift Compression Experiment (NDCX-II) at LBNL. Research and development was carried out on lithium alumino-silicate ion sources prior to NDCX-II source fabrication. Space-charge-limited emission with the current density exceeding 1 mA/cm{sup 2} was measured with 0.64 cm diameter lithium alumino-silicate ion sources at 1275 °C. The beam current density is less for the first 10.9 cm diameter NDCX-II source, and it may be due to an issue of surface coverage. The lifetime of a thin coated (on a tungsten substrate) source is varied, roughly 40–50 h, when pulsed at 0.05 Hz and with pulse length of 6μs each, i.e., a duty factor of 3×10{sup −7}, at an operating temperature of 1250–1275 °C. The 10.9 cm diameter source lifetime is likely the same as of a 0.64 cm source, but the lifetime of a source with a 2 mm diameter (without a tungsten substrate) is 10–15 h with a duty factor of 1 (DC extraction). The lifetime variation is dependent on the amount of deposition of β-eucryptite mass, and the surface temperature. The amount of mass deposition does not significantly alter the current density. More ion source work is needed to improve the large source performance.

  11. Serotonin Depletion Does not Modify the Short-Term Brain Hypometabolism and Hippocampal Neurodegeneration Induced by the Lithium-Pilocarpine Model of Status Epilepticus in Rats.

    Science.gov (United States)

    García-García, Luis; Shiha, Ahmed Anis; Bascuñana, Pablo; de Cristóbal, Javier; Fernández de la Rosa, Rubén; Delgado, Mercedes; Pozo, Miguel A

    2016-05-01

    It has been reported that fluoxetine, a selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitor, has neuroprotective properties in the lithium-pilocarpine model of status epilepticus (SE) in rats. The aim of the present study was to investigate the effect of 5-HT depletion by short-term administration of p-chlorophenylalanine (PCPA), a specific tryptophan hydroxylase inhibitor, on the brain hypometabolism and neurodegeneration induced in the acute phase of this SE model. Our results show that 5-HT depletion did modify neither the brain basal metabolic activity nor the lithium-pilocarpine-induced hypometabolism when evaluated 3 days after the insult. In addition, hippocampal neurodegeneration and astrogliosis triggered by lithium-pilocarpine were not exacerbated by PCPA treatment. These findings point out that in the early latent phase of epileptogenesis, non-5-HT-mediated actions may contribute, at least in some extent, to the neuroprotective effects of fluoxetine in this model of SE.

  12. Cane molasses as a source of precursors in the bioproduction of tryptophan by Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Marzieh Dehghan Shasaltaneh

    2013-09-01

    Full Text Available The essential amino acid L-tryptophan can be produced by a condensation reaction between indole and L-serine, catalyzed by B. subtilis with tryptophan synthase activity. Application of the tryptophan is widespread in the biotechnology domain and is sometimes added to feed products as a food fortifier.The optimum concentration of the Iranian cane molasses was determined by measuring the amount of biomass after growth in 1 to 30 g/mL of molasses. The maximum amount of biomass was obtained in 10 g/mL molasses. Chromatographic methods, TLC and HPLC, were used to assay the amount of tryptophan produced in the presence of precursors of tryptophan production (indole and serine and/or molasses.Our results indicate the importance of the Iranian cane molasses not only as carbon source, but also as a source of precursors for tryptophan production.This report evaluates the potential of cane molasses as an economical source for tryptophan production by B. subtilis, hence eliminating the requirement for additional serine and indole as precursors.

  13. Reduced Dimensionality Lithium Niobate Microsystems

    Energy Technology Data Exchange (ETDEWEB)

    Eichenfield, Matt [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-01

    The following report describes work performed under the LDRD program at Sandia National Laboratories October 2014 and September 2016. The work presented demonstrates the ability of Sandia Labs to develop state-of-the-art photonic devices based on thin film lithium niobate (LiNbO3 ). Section 1 provides an introduction to integrated LiNbO3 devices and motivation for developing thin film nonlinear optical systems. Section 2 describes the design, fabrication, and photonic performance of thin film optical microdisks fabricated from bulk LiNbO3 using a bulk implantation method developed at Sandia. Sections 3 and 4 describe the development of similar thin film LiNbO3 structures fabricated from LiNbO3 on insulator (LNOI) substrates and our demonstration of optical frequency conversion with state-of-the-art efficiency. Finally, Section 5 describes similar microdisk resonators fabricated from LNOI wafers with a buried metal layer, in which we demonstrate electro-optic modulation.

  14. Fluorescence studies with malate dehydrogenase from rhizobium japonicum 3I1B-143 bacteroids: a two-tryptophan containing protein

    Science.gov (United States)

    Ghiron, Camillo A.; Eftink, Maurice R.; Waters, James K.; Emerich, David W.

    1990-05-01

    A number of fluorescence studies, both of trp residues and bound NADH, have been reported for porcine MDH. The large number of trp residues (6) complicates the interpretation of some studies. To circumvent this we have performed studies with a two tryptophan (per subunit) MDH from Rhizobium japonicum 311B-143 bacteroids. We have performed phase/modulation fluorescence lifetime measurements, as a function of temperature and added quencher KI, in order to resolved the 1.3 ns (blue) and 6.6 ns (red) contributions from the two classes of trp residues. Anisotropy decay studies have also been performed. The binding of NADH dynamically quenches the fluorescence of both tip residues, but, unlike mammalian cytoplasmic and mitochondrial MDH, there is not a large enhancement in fluorescence of bound NADH upon forming a ternary complex with either tartronic acid or D-malonate.

  15. Exogenous Tryptophan Promotes Cutaneous Wound Healing of Chronically Stressed Mice through Inhibition of TNF-α and IDO Activation.

    Directory of Open Access Journals (Sweden)

    Luana Graziella Bandeira

    Full Text Available Stress prolongs the inflammatory response compromising the dermal reconstruction and wound closure. Acute stress-induced inflammation increases indoleamine 2, 3-dioxygenase-stimulated tryptophan catabolism. To investigate the role of indoleamine 2, 3-dioxygenase expression and tryptophan administration in adverse effects of stress on cutaneous wound healing, mice were submitted to chronic restraint stress and treated with tryptophan daily until euthanasia. Excisional lesions were created on each mouse and 5 or 7 days later, the lesions were analyzed. In addition, murine skin fibroblasts were exposed to elevated epinephrine levels plus tryptophan, and fibroblast activity was evaluated. Tryptophan administration reversed the reduction of the plasma tryptophan levels and the increase in the plasma normetanephrine levels induced by stress 5 and 7 days after wounding. Five days after wounding, stress-induced increase in the protein levels of tumor necrosis factor-α and indoleamine 2, 3-dioxygenase, and this was inhibited by tryptophan. Stress-induced increase in the lipid peroxidation and the amount of the neutrophils, macrophages and T cells number was reversed by tryptophan 5 days after wounding. Tryptophan administration inhibited the reduction of myofibroblast density, collagen deposition, re-epithelialization and wound contraction induced by stress 5 days after wounding. In dermal fibroblast culture, the tryptophan administration increased the cell migration and AKT phosphorylation in cells treated with high epinephrine levels. In conclusion, tryptophan-induced reduction of inflammatory response and indoleamine 2, 3-dioxygenase expression may have accelerated cutaneous wound healing of chronically stressed mice.

  16. The effect of tryptophan supplemented diets on brain serotonergic activity and plasma cortisol under undisturbed and stressed conditions in grouped-housed Nile tilapia Oreochromis niloticus

    DEFF Research Database (Denmark)

    Martins, C.I.M.; Silva, P.I.M.; Costas, B.

    2013-01-01

    Tryptophan (TRP) supplemented diets have been shown to have therapeutic effects in farmed animals including fish by modulating the activity of the neurotransmitter serotonin (5-hydroxytryptamine; 5-HT). The effects reported in fish have been obtained using individually-housed fish and include......-term supplementation with TRP supplemented diets changes brain serotonergic activity and the stress response associated with slaughter handling in grouped-housed Nile tilapia Oreochromis niloticus. Adult fish (n. =. 108, 490.6. ±. 4.0. g, 12 individuals per tank) were exposed to one of the three treatments...

  17. Metabolic Side Effects of Lithium

    Directory of Open Access Journals (Sweden)

    M. Cagdas Eker

    2010-04-01

    Full Text Available Lithium is an alkaline ion being used since 19th century. After its widespread use in psychiatric disorders, observed side effects caused skepticism about its therapeutic efficacy. Despite several disadvantages, lithium is one of the indispensible drugs used in affective disorders, especially in bipolar disorder. It became a necessity for physicians to recognize its side effects since lithium is still accepted as a gold standard in the treatment of bipolar disorder. Adverse effects of chronic administration of lithium on several organ systems are widely known. In this article metabolic effects of lithium on thyroid and parathyroid glands, body mass index and kidneys will be discussed along with their mechanisms, clinical findings, possible risk factors and treatment. One of the most common side effect of lithium is hypothyroidism. It has the same clinical and biochemical properties as primary hypothyroidism and observed as subclinical hypothyroidism in the first place. Hypothyroidism, even its subclinical form, may be associated with non-response or inadequate response and is indicated as a risk factor for development of rapid cycling bipolar disorder. Therefore, hypothyroidism should be screened no matter how severe it is and should be treated with thyroid hormone in the presence of clinical hypothyroidism. Weight gain due to lithium administration disturbs the compliance to treatment and negatively affects the course of the illness. Increased risk for diabetes, hypertension, ischemic heart disease and stroke because of weight gain constitute other centers of problem. Indeed, it is of importance to determine the risk factors before treatment, to follow up the weight, to re-organize nutritional habits and to schedule exercises. Another frequent problematic side effect of lithium treatment is renal dysfunction which clinically present as nephrogenic diabetes insipidus with the common symptoms of polyuria and polydipsia. Nephrogenic diabetes

  18. Therapeutic Drug Monitoring of Lithium

    DEFF Research Database (Denmark)

    Mose, Tina; Damkier, Per; Petersen, Magnus

    2015-01-01

    BACKGROUND: Serum lithium is monitored to ensure levels within the narrow therapeutic window. This study examines the interlaboratory variation and inaccuracy of lithium monitoring in Denmark. METHODS: In 16 samples consisting of (1) control materials (n = 4), (2) pooled patient serum (n = 5......), and (3) serum from individual patients (n = 7), lithium was measured in 19 laboratories using 20 different instruments. The lithium concentrations were targeted by a reference laboratory. Ion-selective electrode (n = 5), reflective spectrophotometric (RSM, n = 5), and spectrophotometric (n = 10) methods...... of >12%. Seven of these instruments had a systematic positive or negative bias and more so at lower lithium concentrations. Three poorly calibrated instruments were found in the ion-selective electrode group, 3 in the spectrophotometric group, and 2 in the RSM group. The instruments using reflectance...

  19. High rate lithium/thionyl chloride bipolar battery development

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.G. [Yardney Technical Products, Inc., Pawcatuck, CT (United States); Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1995-04-01

    The lithium/thionyl chloride (Li/SOCl{sub 2}) electrochemistry is capable of providing high power and high specific power, especially under pulse discharge conditions, when cells containing thin components are arranged in a bipolar configuration. This paper describes recent work concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells for Sonobuoy application. (orig.)

  20. High rate lithium-thionyl chloride bipolar battery development

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.G.; Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1994-12-31

    The lithium/thionyl chloride system is capable of providing both high power and high energy density when cells containing thin components are arranged in a bipolar configuration. Electrode current densities in excess of 300mA/cm{sup 2} are achieved during pulse discharge. The present work is concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells.

  1. High rate lithium/thionyl chloride bipolar battery development

    Science.gov (United States)

    Russell, P. G.; Goebel, F.

    The lithium/thionyl chloride ( {Li}/{SOCl2}) electrochemistry is capable of providing high power and high specific power, especially under pulse discharge conditions, when cells containing thin components are arranged in a bipolar configuration. This paper describes recent work concerned with bipolar cell design, cathode evaluation, component manufacturing methods, and the assembly and testing of bipolar modules containing up to 150 cells for Sonobuoy application.

  2. Clinical evaluation of 5-hydroxy-L-tryptophan as an antidepressant drug.

    Science.gov (United States)

    Nakajima, T; Kudo, Y; Kaneko, Z

    1978-01-01

    Effectiveness of 5-hydroxy-L-trytophan as an antidepressant drug was studied with 59 patients with depressive symptoms using Rating Scale for Depression made by Clinico-Psychopharmacology Research Group in Japan for a preparatory step of a double blind clinical study of 5-hydroxy-L-tryptophan treatment of depression. A daily dose of 150--300 mg of 5-hydroxyl-L-tryptophan was administered for three weeks. Favorable responses were observed in 40 patients (67.8%), of whom 13 patients were markedly improved. These effects were noticed in 32 patients (80% of the improved patients) within a week of the treatment. Analysis of General Improvement Rating in the various subtypes of depressive symptoms indicated that endogenous depression and involutional or senile depression were the preferable indication of 5-hydroxy-L-tryptophan loading. The main side effects of 5-hydroxy-L-tryptophan were gastrointestinal disturbances which were minimized by the simultaneous administration of metoclopromide or trihexyphenidyl.

  3. Picosecond Fluorescence Dynamics of Tryptophan and 5-Fluorotryptophan in Monellin : Slow Water-Protein Relaxation Unmasked

    NARCIS (Netherlands)

    Xu, Jianhua; Chen, Binbin; Callis, Patrik Robert; Muiño, Pedro L; Rozeboom, Henriette J; Broos, Jaap; Toptygin, Dmitri; Brand, Ludwig; Knutson, Jay R

    2015-01-01

    Time Dependent Fluorescence Stokes (emission wavelength) Shifts (TDFSS) from tryptophan (Trp) following sub-picosecond excitation are increasingly used to investigate protein dynamics, most recently enabling active research interest into water dynamics near the surface of proteins. Unlike many fluor

  4. Irritability rather than depression during interferon treatment is linked to increased tryptophan catabolism

    NARCIS (Netherlands)

    Russo, S; Kema, IP; Haagsma, EB; Boon, JC; Willemse, PHB; Den Boer, JA; De Vries, EGE; Korf, J

    2005-01-01

    Objective: Treatment with recombinant interferon is associated with high rates of psychiatric comorbidity. We investigated the relation between catabolism of the essential amino acid tryptophan, being rate-limiting of peripheral and cerebral serotonin formation, and psychiatric symptoms in patients

  5. Ultraviolet transient absorption, transient grating and photon echo studies of aqueous tryptophan

    Science.gov (United States)

    Ajdarzadeh, Ahmad; Consani, Cristina; Bräm, Olivier; Tortschanoff, Andreas; Cannizzo, Andrea; Chergui, Majed

    2013-08-01

    We compare UV transient grating (TG) experiments of aqueous tryptophan with transient absorption (TA) and fluorescence up-conversion measurements. The TG and TA signals show a bi-exponential rise with sub-ps and ps time constants, which are consistent with the fluorescence studies. Using experimental data, we provide an equation for the homodyne-detected TG signal, taking into account the sub-100 fs internal conversion of tryptophan after excitation. In addition, we measure a sub-100 fs homogeneous electronic dephasing time for tryptophan in water by the photon echo (PE) technique. These measurements provide a consistent picture of excited state dynamics of aqueous tryptophan that may serve as a basis for coherent 2D-UV spectroscopy of biosystems.

  6. Picosecond Fluorescence Dynamics of Tryptophan and 5-Fluorotryptophan in Monellin : Slow Water-Protein Relaxation Unmasked

    NARCIS (Netherlands)

    Xu, Jianhua; Chen, Binbin; Callis, Patrik Robert; Muiño, Pedro L; Rozeboom, Henriette J; Broos, Jaap; Toptygin, Dmitri; Brand, Ludwig; Knutson, Jay R

    2015-01-01

    Time Dependent Fluorescence Stokes (emission wavelength) Shifts (TDFSS) from tryptophan (Trp) following sub-picosecond excitation are increasingly used to investigate protein dynamics, most recently enabling active research interest into water dynamics near the surface of proteins. Unlike many

  7. Detection of water proximity to tryptophan residues in proteins by single photon radioluminescence.

    Science.gov (United States)

    Bicknese, S; Zimet, D; Park, J; van Hoek, A N; Shohet, S B; Verkman, A S

    1995-05-01

    We recently developed a single photon radioluminescence (SPR) technique to measure submicroscopic distances in biological samples [Bicknese et al., and Shahrokh et al., Biophys. J., 63 (1992) 1256-1279]. SPR arises from the excitation of a fluorophore by the energy deposited from a slowing beta decay electron. The purpose of this study was to detect 3H2O molecules near tryptophan residues in proteins by tryptophan SPR. To detect small SPR signals, a sample compartment with reflective ellipsoidal optics was constructed, and amplified signals from a cooled photomultiplier were resolved by pulse-height analysis. A Monte Carlo calculation was carried out to quantify the relationship between SPR signal and 3H2O-tryptophan proximity. Measurements of tryptophan SPR were made on aqueous tryptophan; dissolved melittin (containing a single tryptophan); native and denatured aldolase; dissolved aldolase, monellin, and human serum albumin; and the integral membrane proteins CHIP28 (containing a putative aqueous pore) and MIP26 using 3H2O or the aqueous-phase probe 3H-3-O-methylglucose (OMG). After subtraction of a Bremsstrahlung background signal, the SPR signal from aqueous tryptophan (cps.microCi-1 mumol-1 +/- SE) was 8.6 +/- 0.2 with 3H2O and 7.8 +/- 0.3 with 3HOMG (n = 8). With 3H2O as donor, the SPR signal (cps.microCi-1 mumol-1) was 9.0 +/- 0.3 for monomeric melittin in low salt (trytophan exposed) and 4.6 +/- 0.8 (n = 9) for tetrameric melittin in high salt (tryptophans buried away from aqueous solution). The ratio of SPR signal obtained for aldolase under denaturing conditions of 8 M urea (fluorophores exposed) versus non-denaturing buffer (fluorophores buried) was 1.53 +/- 0.07 (n = 6). Ratios of SPR signals normalized to fluorescence intensities for monellin, aldolase, and human serum albumin, relative to that for d-tryptophan, were 1.42, 1.09, and 1.04, indicating that the cross-section for excitation of fluorophores in proteins is greater than that for tryptophan in

  8. Lithium Reserve Battery.

    Science.gov (United States)

    the high temperature stability of 2M LiAsF6/MF electrolyte solutions. It was found that the addition of small amounts of LiBF4 to these solutions...greatly increased their high temperature storage capabilities. It was determined that the LiBF4 was effective only when lithium metal was also present in...the solution. LiBF4 was able to stabilize solutions prepared with grades of LiAsF6 obtained from other vendors but to a much lesser degree.

  9. Targeting Tryptophan Catabolism: A Novel Method to Block Triple-Negative Breast Cancer Metastasis

    Science.gov (United States)

    2016-04-01

    on the beginnings of this work in http://www.eurekalert.org/pub_releases/2014-12/uocd-ptd121014. php What do you plan to do during the next reporting...14). The essential amino acid tryptophan is required for protein synthesis and is a precursor for the formation of multiple signaling molecules...including serotonin (15). The majority of tryptophan catabolism occurs via the kynurenine pathway, leading to synthesis of NADþ along with intermediate

  10. Effects of Acute Tryptophan Depletion on Three Different Types of Behavioral Impulsivity

    OpenAIRE

    2010-01-01

    Introduction: While central nervous system serotonin has been implicated in a variety of problematic impulsive behaviors, biological manipulation of brain serotonin using acute tryptophan depletion for studying changes in impulsive behavior has received little attention. Methods: Using identical treatment conditions, we examined the effects of reduced serotonin synthesis for each of three matched groups using acute tryptophan depletion. Thirty healthy men and women (ages 18–45) were assigned ...

  11. Effects of dietary L-tryptophan supplementation on intestinal response to chronic unpredictable stress in broilers.

    Science.gov (United States)

    Yue, Yunshuang; Guo, Yuming; Yang, Ying

    2017-07-01

    Stress has been recognized as a critical risk factor for gastrointestinal diseases in both humans and animals. However, nutritional strategies to attenuate stress-induced intestinal barrier function and underlying mechanisms remain largely unknown. This study tested the hypothesis that L-tryptophan enhanced intestinal barrier function by regulating mucosal serotonin metabolism in chronic unpredictable stress-exposed broilers. One-day-old male broilers (Arbor Acres) were fed a basal diet supplemented with or without L-tryptophan in the absence or presence of chronic unpredictable stress. Feed intake, body weight gain, plasma corticosterone and 5-hydroxytryptamine (5-HT), intestinal permeability, mucosal secretory IgA (sIgA), and mRNA levels for tryptophan hydroxylase 1 (TPH1), IL-1β, IL-6, TNF-α, IL-10, protein abundance for claudin-1, occludin, and ZO-1 were determined. Stress exposure led to elevated plasma corticosterone (P L-tryptophan supplementation. Western blot analysis showed that stress exposure resulted in decreased protein abundance for occludin, claudin-1, and ZO-1, which was attenuated by L-tryptophan. mRNA levels for IL-1β, IL-6, and TNF-α were increased, but those for IL-10 were decreased, in the jejunal tissue of broilers subjected to stress. This effect of stress on cytokine expression was abolished by L-tryptophan treatment. The effects of stress were associated with decreased plasma concentration of 5-HT (P L-Tryptophan supplementation markedly attenuated stress-induced alterations in 5-HT and TPH1 mRNA level in jejunal tissues of broilers. Collectively, these results indicate that L-tryptophan supplementation alleviates chronic unpredictable stress-induced intestinal barrier dysfunction by regulating 5-HT metabolism in broilers.

  12. Flexible Enantioselectivity of Tryptophanase Attributable to Benzene Ring in Heterocyclic Moiety of D-Tryptophan

    OpenAIRE

    Akihiko Shimada; Haruka Ozaki

    2012-01-01

    The invariance principle of enzyme enantioselectivity must be absolute because it is absolutely essential to the homochiral biological world. Most enzymes are strictly enantioselective, and tryptophanase is one of the enzymes with extreme absolute enantioselectivity for L-tryptophan. Contrary to conventional knowledge about the principle, tryptophanase becomes flexible to catalyze D-tryptophan in the presence of diammonium hydrogenphosphate. Since D-amino acids are ordinarily inert or functio...

  13. Studies on the biotin-binding site of avidin. Tryptophan residues involved in the active site.

    OpenAIRE

    Gitlin, G; Bayer, E A; Wilchek, M

    1988-01-01

    Egg-white avidin was modified with the tryptophan-specific reagent 2-hydroxy-5-nitrobenzyl bromide. The complete loss of biotin-binding activity was achieved upon modification of an average of one tryptophan residue per avidin subunit. The identity of the modified residues was determined by isolating the relevant tryptic and chymotryptic peptides from CNBr-cleaved avidin fragments. The results demonstrate that Trp-70 and Trp-110 are modified in approximately equivalent proportions. It is beli...

  14. Effects of Tryptophan Content and Backbone Spacing on the Uptake Efficiency of Cell-Penetrating Peptides

    KAUST Repository

    Rydberg, Hanna A.

    2012-07-10

    Cell-penetrating peptides (CPPs) are able to traverse cellular membranes and deliver macromolecular cargo. Uptake occurs through both endocytotic and nonendocytotic pathways, but the molecular requirements for efficient internalization are not fully understood. Here we investigate how the presence of tryptophans and their position within an oligoarginine influence uptake mechanism and efficiency. Flow cytometry and confocal fluorescence imaging are used to estimate uptake efficiency, intracellular distribution and toxicity in Chinese hamster ovarian cells. Further, membrane leakage and lipid membrane affinity are investigated. The peptides contain eight arginine residues and one to four tryptophans, the tryptophans positioned either at the N-terminus, in the middle, or evenly distributed along the amino acid sequence. Our data show that the intracellular distribution varies among peptides with different tryptophan content and backbone spacing. Uptake efficiency is higher for the peptides with four tryptophans in the middle, or evenly distributed along the peptide sequence, than for the peptide with four tryptophans at the N-terminus. All peptides display low cytotoxicity except for the one with four tryptophans at the N-terminus, which was moderately toxic. This finding is consistent with their inability to induce efficient leakage of dye from lipid vesicles. All peptides have comparable affinities for lipid vesicles, showing that lipid binding is not a decisive parameter for uptake. Our results indicate that tryptophan content and backbone spacing can affect both the CPP uptake efficiency and the CPP uptake mechanism. The low cytotoxicity of these peptides and the possibilities of tuning their uptake mechanism are interesting from a therapeutic point of view. © 2012 American Chemical Society.

  15. Effects of Exhaustive Aerobic Exercise on Tryptophan-Kynurenine Metabolism in Trained Athletes.

    Directory of Open Access Journals (Sweden)

    Barbara Strasser

    Full Text Available Exhaustive exercise can cause a transient depression of immune function. Data indicate significant effects of immune activation cascades on the biochemistry of monoamines and amino acids such as tryptophan. Tryptophan can be metabolized through different pathways, a major route being the kynurenine pathway, which is often systemically up-regulated when the immune response is activated. The present study was undertaken to examine the effect of exhaustive aerobic exercise on biomarkers of immune activation and tryptophan metabolism in trained athletes. After a standardized breakfast 2 h prior to exercise, 33 trained athletes (17 women, 16 men performed an incremental cycle ergometer exercise test at 60 rpm until exhaustion. After a 20 min rest phase, the participants performed a 20 min maximal time-trial on a cycle ergometer (RBM Cyclus 2, Germany. During the test, cyclists were strongly encouraged to choose a maximal pedalling rate that could be maintained for the respective test duration. Serum concentrations of amino acids tryptophan, kynurenine, phenylalanine, and tyrosine were determined by HPLC and immune system biomarker neopterin by ELISA at rest and immediately post exercise. Intense exercise was associated with a strong increase in neopterin concentrations (p<0.001, indicating increased immune activation following intense exercise. Exhaustive exercise significantly reduced tryptophan concentrations by 12% (p<0.001 and increased kynurenine levels by 6% (p = 0.022. Also phenylalanine to tyrosine ratios were lower after exercise as compared with baseline (p<0.001. The kynurenine to tryptophan ratio correlated with neopterin (r = 0.560, p<0.01. Thus, increased tryptophan catabolism by indoleamine 2,3-dioxygenase appears likely. Peak oxygen uptake correlated with baseline tryptophan and kynurenine concentrations (r = 0.562 and r = 0.511, respectively, both p<0.01. Findings demonstrate that exhaustive aerobic exercise is associated with

  16. Syntheses and Self-assembling Behaviors of Pentagonal Conjugates of Tryptophane Zipper-Forming Peptide

    Directory of Open Access Journals (Sweden)

    Nobuo Kimizuka

    2011-08-01

    Full Text Available Pentagonal conjugates of tryptophane zipper-forming peptide (CKTWTWTE with a pentaazacyclopentadecane core (Pentagonal-Gly-Trpzip and Pentagonal-Ala-Trpzip were synthesized and their self-assembling behaviors were investigated in water. Pentagonal-Gly-Trpzip self-assembled into nanofibers with the width of about 5 nm in neutral water (pH 7 via formation of tryptophane zipper, which irreversibly converted to nanoribbons by heating. In contrast, Pentagonal-Ala-Trpzip formed irregular aggregates in water.

  17. The maize auxotrophic mutant orange pericarp is defective in duplicate genes for tryptophan synthase beta.

    Science.gov (United States)

    Wright, A D; Moehlenkamp, C A; Perrot, G H; Neuffer, M G; Cone, K C

    1992-06-01

    orange pericarp (orp) is a seedling lethal mutant of maize caused by mutations in the duplicate unlinked recessive loci orp1 and orp2. Mutant seedlings accumulate two tryptophan precursors, anthranilate and indole, suggesting a block in tryptophan biosynthesis. Results from feeding studies and enzyme assays indicate that the orp mutant is defective in tryptophan synthase beta activity. Thus, orp is one of only a few amino acid auxotrophic mutants to be characterized in plants. Two genes encoding tryptophan synthase beta were isolated from maize and sequenced. Both genes encode polypeptides with high homology to tryptophan synthase beta enzymes from other organisms. The cloned genes were mapped by restriction fragment length polymorphism analysis to approximately the same chromosomal locations as the genetically mapped factors orp1 and orp2. RNA analysis indicates that both genes are expressed in all tissues examined from normal plants. Together, the biochemical, genetic, and molecular data verify the identity of orp1 and orp2 as duplicate structural genes for the beta subunit of tryptophan synthase.

  18. Flexible Enantioselectivity of Tryptophanase Attributable to Benzene Ring in Heterocyclic Moiety of D-Tryptophan

    Directory of Open Access Journals (Sweden)

    Akihiko Shimada

    2012-05-01

    Full Text Available The invariance principle of enzyme enantioselectivity must be absolute because it is absolutely essential to the homochiral biological world. Most enzymes are strictly enantioselective, and tryptophanase is one of the enzymes with extreme absolute enantioselectivity for L-tryptophan. Contrary to conventional knowledge about the principle, tryptophanase becomes flexible to catalyze D-tryptophan in the presence of diammonium hydrogenphosphate. Since D-amino acids are ordinarily inert or function as inhibitors even though they are bound to the active site, the inhibition behavior of D-tryptophan and several inhibitors involved in this process was examined in terms of kinetics to explain the reason for this flexible enantioselectivity in the presence of diammonium hydrogenphosphate. Diammonium hydrogenphosphate gave tryptophanase a small conformational change so that D-tryptophan could work as a substrate. As opposed to other D-amino acids, D-tryptophan is a very bulky amino acid with a benzene ring in its heterocyclic moiety, and so we suggest that this structural feature makes the catalysis of D-tryptophan degradation possible, consequently leading to the flexible enantioselectivity. The present results not only help to understand the mechanism of enzyme enantioselectivity, but also shed light on the origin of homochirality.

  19. L-Tryptophan Production in Escherichia coli Improved by Weakening the Pta-AckA Pathway.

    Science.gov (United States)

    Liu, Lina; Duan, Xuguo; Wu, Jing

    2016-01-01

    Acetate accumulation during the fermentation process of Escherichia coli FB-04, an L-tryptophan production strain, is detrimental to L-tryptophan production. In an initial attempt to reduce acetate formation, the phosphate acetyltransferase gene (pta) from E. coli FB-04 was deleted, forming strain FB-04(Δpta). Unfortunately, FB-04(Δpta) exhibited a growth defect. Therefore, pta was replaced with a pta variant (pta1) from E. coli CCTCC M 2016009, forming strain FB-04(pta1). Pta1 exhibits lower catalytic capacity and substrate affinity than Pta because of a single amino acid substitution (Pro69Leu). FB-04(pta1) lacked the growth defect of FB-04(Δpta) and showed improved fermentation performance. Strain FB-04(pta1) showed a 91% increase in L-tryptophan yield in flask fermentation experiments, while acetate production decreased by 35%, compared with its parent FB-04. Throughout the fed-batch fermentation process, acetate accumulation by FB-04(pta1) was slower than that by FB-04. The final L-tryptophan titer of FB-04(pta1) reached 44.0 g/L, representing a 15% increase over that of FB-04. Metabolomics analysis showed that the pta1 genomic substitution slightly decreased carbon flux through glycolysis and significantly increased carbon fluxes through the pentose phosphate and common aromatic pathways. These results indicate that this strategy enhances L-tryptophan production and decreases acetate accumulation during the L-tryptophan fermentation process.

  20. Liver and brain tryptophan metabolism following hydrocortisone administration to rats and gerbils.

    Science.gov (United States)

    Green, A R; Sourkes, T L; Young, S N

    1975-02-01

    1 Liver tryptophan pyrrolase activity is low in the mongolian gerbil (Meriones unguiculatus) and is not induced by hydrocortisone (5 mg/kg). In contrast, there is measurable activity in the rat liver and this is induced by hydrocortisone. In vivo measurements confirmed the absence of induction in gerbils but suggested that they were able to metabolize tryptophan. However no detectable pyrrolase activity was found in any other tissues either before or after hydrocortisone. 2 In agreement with previous observations hydrocortisone decreased rat brain 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) 6 h after administration. Brain tryptophan concentrations were also decreased at this time. In contrast, hydrocortisone did not alter gerbil brain 5-HT, 5-HIAA or trytophan. alpha-Methyltryptophan activated hepatic tryptophan pyrrolase and decreased brain 5-HT and 5-HIAA in both animals. 3 Results suggest that the decrease in rat brain 5-HT and 5-HIAA following hydrocortisone may be associated with the rise in liver tryptophan pyrrolase and that the brain amine changes are mediated through the decrease in brain tryptophan concentration.

  1. Flexible enantioselectivity of tryptophanase attributable to benzene ring in heterocyclic moiety of d-tryptophan.

    Science.gov (United States)

    Shimada, Akihiko; Ozaki, Haruka

    2012-01-01

    The invariance principle of enzyme enantioselectivity must be absolute because it is absolutely essential to the homochiral biological world. Most enzymes are strictly enantioselective, and tryptophanase is one of the enzymes with extreme absolute enantioselectivity for L-tryptophan. Contrary to conventional knowledge about the principle, tryptophanase becomes flexible to catalyze D-tryptophan in the presence of diammonium hydrogenphosphate. Since D-amino acids are ordinarily inert or function as inhibitors even though they are bound to the active site, the inhibition behavior of D-tryptophan and several inhibitors involved in this process was examined in terms of kinetics to explain the reason for this flexible enantioselectivity in the presence of diammonium hydrogenphosphate. Diammonium hydrogenphosphate gave tryptophanase a small conformational change so that D-tryptophan could work as a substrate. As opposed to other D-amino acids, D-tryptophan is a very bulky amino acid with a benzene ring in its heterocyclic moiety, and so we suggest that this structural feature makes the catalysis of D-tryptophan degradation possible, consequently leading to the flexible enantioselectivity. The present results not only help to understand the mechanism of enzyme enantioselectivity, but also shed light on the origin of homochirality.

  2. Efficient isotopic tryptophan labeling of membrane proteins by an indole controlled process conduct.

    Science.gov (United States)

    Berger, Christian; Berndt, Sandra; Pichert, Annelie; Theisgen, Stephan; Huster, Daniel

    2013-06-01

    A protocol for the efficient isotopic labeling of large G protein-coupled receptors with tryptophan in Escherichia coli as expression host was developed that sufficiently suppressed the naturally occurring L-tryptophan indole lyase, which cleaves tryptophan into indole, pyruvate, and ammonia resulting in scrambling of the isotopic label in the protein. Indole produced by the tryptophanase is naturally used as messenger for cell-cell communication. Detailed analysis of different process conducts led to the optimal expression strategy, which mimicked cell-cell communication by the addition of indole during expression. Discrete concentrations of indole and (15) N2 -L-tryptophan at dedicated time points in the fermentation drastically increased the isotopic labeling efficiency. Isotope scrambling was only observed in glutamine, asparagine, and arginine side chains but not in the backbone. This strategy allows producing specifically tryptophan labeled membrane proteins at high concentrations avoiding the disadvantages of the often low yields of auxotrophic E. coli strains. In the fermentation process carried out according to this protocol, we produced ∼15 mg of tryptophan labeled neuropeptide Y receptor type 2 per liter medium.

  3. L-Tryptophan's effects on brain chemistry and sleep in cats and rats: a review.

    Science.gov (United States)

    Radulovacki, M

    1982-01-01

    In this review I shall discuss published and unpublished work from my laboratory dealing with L-tryptophan's effects on brain monoamines and sleep in cats and rats. From our work it appears that normal animals may not be suitable subjects for testing sleep-inducing effect of tryptophan since their slow-wave sleep (SWS) latency is relatively short. In polyphasic sleepers like cats, we did not observe tryptophan's hypnotic effect with any dosage used (10, 30 or 135 mg/kg). However, we found small, but statistically significant, sleep-inducing effect of tryptophan (30 mg/kg, IP) in normal rats. We have tried, therefore, to create insomniac cats with long sleep latencies by using methysergide, a serotonin receptor blocker. The results show that in insomniac cats hypnotic effect of tryptophan, a precursor to brain serotonin, was observed. It involved not only reduction of sleep latencies but also an increase in SWS. It seems likely that tryptophan's partial reversal of methysergide's effect in cats occurred via a dual mechanism of serotonergic activation and catecholaminergic deactivation, while its sleep-inducing effect in normal rats may have been due to the attenuation of the activity of brain catecholamines.

  4. Tryptophan metabolism and immunogenetics in major depression: a role for interferon-γ gene.

    Science.gov (United States)

    Myint, Aye Mu; Bondy, Brigitta; Baghai, Thomas C; Eser, Daniela; Nothdurfter, Caroline; Schüle, Cornelius; Zill, Peter; Müller, Norbert; Rupprecht, Rainer; Schwarz, Markus J

    2013-07-01

    The tryptophan metabolism and immune activation play a role in pathophysiology of major depressive disorders. The pro-inflammatory cytokine interferon-γ transcriptionally induces the indoleamine 2,3-dioxygenase enzyme that degrades the tryptophan and thus induces serotonin depletion. The polymorphism of certain cytokine genes was reported to be associated with major depression. We investigated the association between interferon-γ (IFNγ) gene CA repeat polymorphism, the profile of serotonin and tryptophan pathway metabolites and clinical parameters in 125 depressed patients and 93 healthy controls. Compared to controls, serum tryptophan and 5-hydroxyindoleacetic acid (5HIAA) concentrations in the patients were significantly lower and serum kynurenine concentrations were significantly higher at baseline (p<0.0001). The presence of IFNγ CA repeat allele 2 homozygous has significant association with higher kynurenine concentrations in controls (F=4.47, p=0.038) as well as in patients (F=3.79, p=0.045). The existence of interferon-γ CA repeat allele 2 (homo- or heterozygous) showed significant association with increase of tryptophan breakdown over time during the study period (F=6.0, p=0.019). The results indicated the association between IFNγ CA repeat allele 2, tryptophan metabolism and the effect of medication.

  5. Tryptophan probes at the α-synuclein and membrane interface

    Science.gov (United States)

    Pfefferkorn, Candace M.; Lee, Jennifer C.

    2010-01-01

    Understanding how environmental factors affect the conformational dynamics of α-synuclein (α-syn) is of great importance because the accumulation and deposit of aggregated α-syn in the brain are intimately connected to Parkinson’s disease etiology. Measurements of steady-state and time-resolved fluorescence of single tryptophan-containing α-syn variants have revealed distinct phospholipid vesicle and micelle interactions at residues 4, 39, 94, and 125. Our circular dichroism (CD) data confirm that Trp mutations do not affect α-syn membrane binding properties (apparent association constant Kaapp∼1×107M−1 for all synucleins) saturating at an estimated lipid-to-protein molar ratio of 380 or approximately 120 proteins covering ~7% of the surface area of an 80 nm diameter vesicle. Fluorophores at positions 4 and 94 are the most sensitive to the lipid bilayer with pronounced spectral blue-shifts (W4: Δλmax ~23 nm; W94: Δλmax ~10 nm) and quantum yield increases (W4, W94: ~3 fold) while W39 and W125 remain primarily water-exposed. Time-resolved fluorescence data show that all sites (except W125) have subpopulations that interact with the membrane. PMID:20229987

  6. Cloning, expression, purification and characterization of tryptophan hydroxylase variants

    DEFF Research Database (Denmark)

    Boesen, Jane

    ). The main goal was to purify full-length hTPH1. Based on earlier results, hTPH1 was purified using detergent in the purification methods. After incubation of the hTPH1 sample with 0.1 % of n-dodecyl-β-D-maltopyranoside (DDM) the protein binds to the anion exchange column and elutes over a large area...... in the anion exchange, indicating that the protein still exists in different oligomer forms. This was also observed in the gel filtration. Variants of both hTPH1 and hTPH2 containing the regulatory domain or parts of it were constructed and tested for expression in Escherichia coli as well as solubility...... was determined and compared with parameters of chTPH2. Large differences were observed between the two isoforms and tryptophan inhibition was observed for chTPH1 but not for chTPH2. Mass spectrometric analysis of chTPH1 shows that the sample contains two species: chTPH1 and another species, which could...

  7. Novel tryptophan metabolic pathways in auxin biosynthesis in silkworm.

    Science.gov (United States)

    Yokoyama, Chiaki; Takei, Mami; Kouzuma, Yoshiaki; Nagata, Shinji; Suzuki, Yoshihito

    2017-08-01

    In the course of our study of the biosynthetic pathway of auxin, a class of phytohormones, in insects, we proposed the biosynthetic pathway tryptophan (Trp)→indole-3-acetaldoxime (IAOx)→indole-3-acetadehyde (IAAld)→indole-3-acetic acid (IAA). In this study, we identified two branches in the metabolic pathways in the silkworm, possibly affecting the efficiency of IAA production: Trp→indole-3-pyruvic acid→indole-3-lactic acid and IAAld→indole-3-ethanol. We also determined the apparent conversion activities (2.05×10(-7)UmL(-1) for Trp→IAA, 1.30×10(-5)UmL(-1) for IAOx→IAA, and 3.91×10(-1)UmL(-1) for IAAld→IAA), which explain why IAOx and IAAld are barely detectable as either endogenous compounds or metabolites of their precursors. The failure to detect IAAld, even in the presence of an inhibitor of the conversion IAAld→IAA, is explained by a switch in the conversion from IAAld→IAA to IAAld→IEtOH. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Hydration of protonated aromatic amino acids: phenylalanine, tryptophan, and tyrosine.

    Science.gov (United States)

    Gao, Bing; Wyttenbach, Thomas; Bowers, Michael T

    2009-04-01

    The first steps of hydration of the protonated aromatic amino acids phenylalanine, tryptophan, and tyrosine were studied experimentally employing a mass spectrometer equipped with a drift cell to examine the sequential addition of individual water molecules in equilibrium experiments and theoretically by a combination of molecular mechanics and electronic structure calculations (B3LYP/6-311++G**) on the three amino acid systems including up to five water molecules. It is found that both the ammonium and carboxyl groups offer good water binding sites with binding energies of the order of 13 kcal/mol for the first water molecule. Subsequent water molecules bind less strongly, in the range of 7-11 kcal/mol for the second through fifth water molecules. The ammonium group is able to host up to three water molecules and the carboxyl group one water molecule before additional water molecules bind either to the amino acid side chain as in tyrosine or to already-bound water in a second solvation shell around the ammonium group. Reasons for the surprisingly high water affinity of the neutral carboxyl group, comparable to that of the charge-carrying ammonium group, are found to be high intrinsic hydrophilicity, favorable charge-dipole alignment, and--for the case of multiply hydrated species--favorable dipole-dipole interaction among water molecules and the lack of alternative fully exposed hydration sites.

  9. A lithium superionic conductor.

    Science.gov (United States)

    Kamaya, Noriaki; Homma, Kenji; Yamakawa, Yuichiro; Hirayama, Masaaki; Kanno, Ryoji; Yonemura, Masao; Kamiyama, Takashi; Kato, Yuki; Hama, Shigenori; Kawamoto, Koji; Mitsui, Akio

    2011-07-31

    Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10(-2) S cm(-1)) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li(10)GeP(2)S(12) that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm(-1) at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window).

  10. PeP-neutrino Detection by Lithium Detector as a Direct Way to Search for Oscillation of Solar Neutrinos

    CERN Document Server

    Kopylov, A V

    2000-01-01

    The high sensitivity of lithium detector to pep- and Be7-neutrinos makes a lithium radiochemical detector a powerful tool for the search of the oscillations of solar neutrinos. The first phase of lithium experiment on the installation with 10 tons of metallic lithium will enable to collect data within 1 year of measurements to provide very definite information about SMA MSW solution. the second phase with 10 modules 10 tons each will measure the semiannual variations of the signal, thus the contributions of pep- and Be7-lines will be weighted, what will give a "smoking-gun" evidence about "just-so" solution for large mixing angles and delta-m2 about 10-10 - 10-9 eV2. If both regions are not confirmed the results of lithium detector can be interpreted in favor of LMA MSW solution.

  11. Status of the Space-Rated Lithium-Ion Battery Advanced Development Project in Support of the Exploration Vision

    Science.gov (United States)

    Miller, Thomas

    2007-01-01

    The NASA Glenn Research Center (GRC), along with the Goddard Space Flight Center (GSFC), Jet Propulsion Laboratory (JPL), Johnson Space Center (JSC), Marshall Space Flight Center (MSFC), and industry partners, is leading a space-rated lithium-ion advanced development battery effort to support the vision for Exploration. This effort addresses the lithium-ion battery portion of the Energy Storage Project under the Exploration Technology Development Program. Key discussions focus on the lithium-ion cell component development activities, a common lithium-ion battery module, test and demonstration of charge/discharge cycle life performance and safety characterization. A review of the space-rated lithium-ion battery project will be presented highlighting the technical accomplishments during the past year.

  12. Tryptophan 2,3-dioxygenase (TDO)-reactive T cells differ in their functional characteristics in health and cancer

    Science.gov (United States)

    Hjortsø, Mads Duus; Larsen, Stine Kiaer; Kongsted, Per; Met, Özcan; Frøsig, Thomas Mørch; Andersen, Gitte Holmen; Ahmad, Shamaila Munir; Svane, Inge Marie; Becker, Jürgen C; Straten, Per thor; Andersen, Mads Hald

    2015-01-01

    Tryptophan-2,3-dioxygenase (TDO) physiologically regulates systemic tryptophan levels in the liver. However, numerous studies have linked cancer with activation of local and systemic tryptophan metabolism. Indeed, similar to other heme dioxygenases TDO is constitutively expressed in many cancers. In the present study, we detected the presence of both CD8+ and CD4+ T-cell reactivity toward TDO in peripheral blood of patients with malignant melanoma (MM) or breast cancer (BC) as well as healthy subjects. However, TDO-reactive CD4+ T cells constituted distinct functional phenotypes in health and disease. In healthy subjects these cells predominately comprised interferon (IFN)γ and tumor necrosis factor (TNF)-α producing Th1 cells, while in cancer patients TDO-reactive CD4+ T-cells were more differentiated with release of not only IFNγ and TNFα, but also interleukin (IL)-17 and IL-10 in response to TDO-derived MHC-class II restricted peptides. Hence, in healthy donors (HD) a Th1 helper response was predominant, whereas in cancer patients CD4+ T-cell responses were skewed toward a regulatory T cell (Treg) response. Furthermore, MM patients hosting a TDO-specific IL-17 response showed a trend toward an improved overall survival (OS) compared to MM patients with IL-10 producing, TDO-reactive CD4+ T cells. For further characterization, we isolated and expanded both CD8+ and CD4+ TDO-reactive T cells in vitro. TDO-reactive CD8+ T cells were able to kill HLA-matched tumor cells of different origin. Interestingly, the processed and presented TDO-derived epitopes varied between different cancer cells. With respect to CD4+ TDO-reactive T cells, in vitro expanded T-cell cultures comprised a Th1 and/or a Treg phenotype. In summary, our data demonstrate that the immune modulating enzyme TDO is a target for CD8+ and CD4+ T cell responses both in healthy subjects as well as patients with cancer; notably, however, the functional phenotype of these T-cell responses differ

  13. Lithium metal doped electrodes for lithium-ion rechargeable chemistry

    Science.gov (United States)

    Liu, Gao; Battaglia, Vince; Wang, Lei

    2016-09-13

    An embodiment of the invention combines the superior performance of a polyvinylidene difluoride (PVDF) or polyethyleneoxide (POE) binder, the strong binding force of a styrene-butadiene (SBR) binder, and a source of lithium ions in the form of solid lithium metal powder (SLMP) to form an electrode system that has improved performance as compared to PVDF/SBR binder based electrodes. This invention will provide a new way to achieve improved results at a much reduced cost.

  14. The DELTA 181 lithium thionyl chloride battery

    Science.gov (United States)

    Sullivan, Ralph M.; Brown, Lawrence E.; Leigh, A. P.

    In 1986, the Johns Hopkins University/Applied Physics Laboratory (JHU/APL) undertook the development of a sensor module for the DELTA 181 spacecraft, a low earth orbit (LEO) mission of less than two months duration. A large lithium thionyl chloride battery was developed as the spacecraft's primary power source, the first known such use for this technology. The exceptionally high energy density of the lithium thionyl chloride cell was the primary driver for its use, resulting in a completed battery with a specific energy density of 120 Wh/lb. Safety requirements became the primary driver shaping all aspects of the power system design and development due to concerns about the potential hazards of this relatively new, high-energy technology. However, the program was completed without incident. The spacecraft was launched on February 8, 1988, from Kennedy Space Center (KSC) with over 60,000 Wh of battery energy. It reentered on April 2, 1988, still operating after 55 days, providing a successful, practical, and visible demonstration of the use of this technology for spacecraft applications.

  15. Progress of the French program on lithium polymer battery

    Energy Technology Data Exchange (ETDEWEB)

    Huglo, F.; Marginedes, D. [BOLLORE, Quimper (France); Lascaud, S. [ELECTRICITE DE FRANCE, Moret sur Loing (France); Angot, P. [SCHNEIDER ELECTRIC, Grenoble (France)

    2000-07-01

    Energy storage systems that are reliable, safe, high energy density, low-cost, intelligent and recyclable are a must for the promotion of electric vehicles. One of the most promising technologies in that field is the lithium polymer battery. 1991 saw the development of batteries based on metallic lithium and dry polymer electrolyte with emphasis on solvent-less and high productive process technology to meet stated objectives concerning performances and cost. This was a joint effort by Bollore, Electricite de France and Schneider. The research phase was concluded in 1997. By the end of 2000, it is expected that the assembly of the first modules will be completed. The high potential for lithium polymer technology combined with extrusion manufacturing process to match automotive requirements in terms of safety, performance, and price was confirmed and product development is well on the way. Parallel to this development, the companies are at work on the development of a recycling project to guarantee the recovery of vanadium and lithium compounds and take into account environmental and safety concerns. tabs., figs.

  16. Tryptophanase-catalyzed L-tryptophan synthesis from D-serine in the presence of diammonium hydrogen phosphate.

    Science.gov (United States)

    Shimada, Akihiko; Ozaki, Haruka; Saito, Takeshi; Noriko, Fujii

    2009-06-01

    Tryptophanase, an enzyme with extreme absolute stereospecificity for optically active stereoisomers, catalyzes the synthesis of l-tryptophan from l-serine and indole through a beta-substitution mechanism of the ping-pong type, and has no activity on d-serine. We previously reported that tryptophanase changed its stereospecificity to degrade d-tryptophan in highly concentrated diammonium hydrogen phosphate, (NH(4))(2)HPO(4) solution. The present study provided the same stereospecific change seen in the d-tryptophan degradation reaction also occurs in tryptophan synthesis from d-serine. Tryptophanase became active to d-serine to synthesize l-tryptophan in the presence of diammonium hydrogen phosphate. This reaction has never been reported before. d-serine seems to undergo beta-replacement via an enzyme-bonded alpha-aminoacylate intermediate to yield l-tryptophan.

  17. Optimizing lithium dosing in hemodialysis

    DEFF Research Database (Denmark)

    Bjarnason, N H; Munkner, R; Kampmann, J P

    2006-01-01

    We studied a 62-year-old female hemodialysis patient during initiation and maintenance of lithium carbonate therapy. Three different methods were applied to estimate the regimen: a scenario based on volume of distribution (V(d)), a scenario based on glomerular filtration rate (GFR), and a scenario...... estimates. Furthermore, the maintenance dose estimated from the central compartment (V1) led to plasma concentrations within the therapeutic range. Thus, a regimen where 12.2 mmol lithium was given after each hemodialysis session resulted in stable between-dialysis plasma lithium concentrations...... in this patient with no residual kidney function. We did not observe adverse effects related to this regimen, which was monitored from 18 days to 8 months of therapy, and the patient experienced relief from her severe depressive disorder. In conclusion, dialysis patients may be treated with lithium administrated...

  18. Does lithium protect against dementia?

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Forman, Julie Lyng; Andersen, Per Kragh

    2010-01-01

    OBJECTIVE: To investigate whether treatment with lithium in patients with mania or bipolar disorder is associated with a decreased rate of subsequent dementia. METHODS: Linkage of register data on prescribed lithium in all patients discharged from psychiatric health care service with a diagnosis...... exposed to lithium (50.4%), 1,781 to anticonvulsants (36.7%), 4,280 to antidepressants (88.1%), and 3,901 to antipsychotics (80.3%) during the study period. A total of 216 patients received a diagnosis of dementia during follow-up (103.6/10,000 person-years). During the period following the second...... prescription of lithium, the rate of dementia was decreased compared to the period following the first prescription. In contrast, the rates of dementia during multiple prescription periods with anticonvulsants, antidepressants, or antipsychotics, respectively, were not significantly decreased compared...

  19. Rechargeable Lithium Metal Cell Project

    Data.gov (United States)

    National Aeronautics and Space Administration — PSI proposes to develop a rechargeable lithium metal cell with energy density >400Wh/kg. This represents a >70% increase as compared to similarly constructed...

  20. Rotational Mixing and Lithium Depletion

    CERN Document Server

    Pinsonneault, M H

    2010-01-01

    I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time. New developments related to the possible suppression of mixing at late ages, close binary mergers and their lithium signature, and an alternate origin for dispersion in young cool stars tied to radius anomalies observed in active young stars are discussed. I highlight uncertainties in models of Population II lithium depletion and dispersion related to the treatment of angular momentum loss. Finally, the origins of rotation are tied to conditions in the pre-main sequence, and there is thus some evidence that enviroment and planet formation could impact stellar rotational properties. This may be related to recent observational evidence for cluster to cluster variations in lithium depletion and a connection between the presence of planets and s...

  1. Lithium Abundance of Metal-poor Stars

    Institute of Scientific and Technical Information of China (English)

    Hua-Wei Zhang; Gang Zhao

    2003-01-01

    High-resolution, high signal-to-noise ratio spectra have been obtained for 32 metal-poor stars. The equivalent widths of Li λ6708A were measured and the lithium abundances were derived. The average lithium abundance of 21 stars on the lithium plateau is 2.33±0.02 dex. The Lithium plateau exhibits a marginal trend along metallicity, dA(Li)/d[Fe/H] = 0.12±0.06, and no clear trend with the effective temperature. The trend indicates that the abundance of lithium plateau may not be primordial and that a part of the lithium was produced in Galactic Chemical Evolution (GCE).

  2. Lithium compensation for full cell operation

    Science.gov (United States)

    Xiao, Jie; Zheng, Jianming; Chen, Xilin; Lu, Dongping; Liu, Jun; Jiguang, Jiguang

    2016-05-17

    Disclosed herein are embodiments of a lithium-ion battery system comprising an anode, an anode current collector, and a layer of lithium metal in contact with the current collector, but not in contact with the anode. The lithium compensation layer dissolves into the electrolyte to compensate for the loss of lithium ions during usage of the full cell. The specific placement of the lithium compensation layer, such that there is no direct physical contact between the lithium compensation layer and the anode, provides certain advantages.

  3. Therapeutic Mechanisms of Lithium in Bipolar Disorder: Recent Advances and Current Understanding.

    Science.gov (United States)

    Malhi, Gin S; Outhred, Tim

    2016-10-01

    Lithium is the most effective and well established treatment for bipolar disorder, and it has a broad array of effects within cellular pathways. However, the specific processes through which therapeutic effects occur and are maintained in bipolar disorder remain unclear. This paper provides a timely update to an authoritative review of pertinent findings that was published in CNS Drugs in 2013. A literature search was conducted using the Scopus database, and was limited by year (from 2012). There has been a resurgence of interest in lithium therapy mechanisms, perhaps driven by technical advancements in recent years that permit the examination of cellular mechanisms underpinning the effects of lithium-along with the reuptake of lithium in clinical practice. Recent research has further cemented glycogen synthase kinase 3β (GSK3β) inhibition as a key mechanism, and the inter-associations between GSK3β-mediated neuroprotective, anti-oxidative and neurotransmission mechanisms have been further elucidated. In addition to highly illustrative cellular research, studies examining higher-order biological systems, such as circadian rhythms, as well as employing innovative animal and human models, have increased our understanding of how lithium-induced changes at the cellular level possibly translate to changes at behavioural and clinical levels. Neural circuitry research is yet to identify clear mechanisms of change in bipolar disorder in response to treatment with lithium, but important structural findings have demonstrated links to the modulation of cellular mechanisms, and peripheral marker and pharmacogenetic studies are showing promising findings that will likely inform the exploration for predictors of lithium treatment response. With a deeper understanding of lithium's therapeutic mechanisms-from the cellular to clinical levels of investigation-comes the opportunity to develop predictive models of lithium treatment response and identify novel drug targets, and

  4. Lithium isotope separation by laser

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, T.; Maruyama, Y.; Suzuki, Y.; Shiba, K.

    1982-01-01

    A lithium isotope separation was performed using a laser isotope separation method. It was found that the lithium atoms with a natural isotopic abundance enhanced its /sup 6/Li concentration up to over 90% by tuning the laser wavelength to the /sup 2/Psub(1/2) of /sup 6/Li. Too high power, however, leads to a loss of enrichment due to the power broadening effect which was analysed by the equation of motion of density matrices.

  5. Air breathing lithium power cells

    Science.gov (United States)

    Farmer, Joseph C.

    2014-07-15

    A cell suitable for use in a battery according to one embodiment includes a catalytic oxygen cathode; a stabilized zirconia electrolyte for selective oxygen anion transport; a molten salt electrolyte; and a lithium-based anode. A cell suitable for use in a battery according to another embodiment includes a catalytic oxygen cathode; an electrolyte; a membrane selective to molecular oxygen; and a lithium-based anode.

  6. The lithium air battery fundamentals

    CERN Document Server

    Imanishi, Nobuyuki; Bruce, Peter G

    2014-01-01

    Lithium air rechargeable batteries are the best candidate for a power source for electric vehicles, because of their high specific energy density. In this book, the history, scientific background, status and prospects of the lithium air system are introduced by specialists in the field. This book will contain the basics, current statuses, and prospects for new technologies. This book is ideal for those interested in electrochemistry, energy storage, and materials science.

  7. Kleptomania, mood disorder and lithium

    OpenAIRE

    Fábio Lopes Rocha; Maria Elizabete Guimarães Rocha

    1992-01-01

    Kleptomania has been found in association with major depression in a fairly large number of reports in recent years. We describe a patient with concurrent DSM-III-R Bipolar Mood Disorder and Kleptomania, whose symptoms remitted completely, apparently in response to lithium therapy, which raised the possibility that pharmacological treatment may benefit kleptomania. Further studies are needed to establish the possible relationship between kleptomania, mood disorders and lithium therapy.

  8. Kleptomania, mood disorder and lithium

    Directory of Open Access Journals (Sweden)

    Fábio Lopes Rocha

    1992-12-01

    Full Text Available Kleptomania has been found in association with major depression in a fairly large number of reports in recent years. We describe a patient with concurrent DSM-III-R Bipolar Mood Disorder and Kleptomania, whose symptoms remitted completely, apparently in response to lithium therapy, which raised the possibility that pharmacological treatment may benefit kleptomania. Further studies are needed to establish the possible relationship between kleptomania, mood disorders and lithium therapy.

  9. Modeling the Lithium Ion Battery

    Science.gov (United States)

    Summerfield, John

    2013-01-01

    The lithium ion battery will be a reliable electrical resource for many years to come. A simple model of the lithium ions motion due to changes in concentration and voltage is presented. The battery chosen has LiCoO[subscript 2] as the cathode, LiPF[subscript 6] as the electrolyte, and LiC[subscript 6] as the anode. The concentration gradient and…

  10. Modeling the Lithium Ion Battery

    Science.gov (United States)

    Summerfield, John

    2013-01-01

    The lithium ion battery will be a reliable electrical resource for many years to come. A simple model of the lithium ions motion due to changes in concentration and voltage is presented. The battery chosen has LiCoO[subscript 2] as the cathode, LiPF[subscript 6] as the electrolyte, and LiC[subscript 6] as the anode. The concentration gradient and…

  11. From tryptophan to hydroxytryptophan: reflections on a busy life.

    Science.gov (United States)

    Fisher, Hans

    2009-01-01

    Given the very difficult odyssey of my early years, who could have imagined the incredible and successful journey that constituted my life path after age 13? I was born into a Jewish family in Breslau, Germany, right before the rise of Nazism and Hitler's election. After Kristallnacht, when my father was taken to Buchenwald Concentration Camp, we had to leave Germany as soon as possible. The first opportunity came in May of 1939, when we boarded the SS St. Louis bound for Havana, Cuba. Almost all passengers were denied entrance into Cuba, and the ship had to go back to Europe, where I ended up in France. In December of 1939, during World War II, I was fortunate to be able to leave France. This time I made it to Cuba, where my father was already in residence. A year later, my entire family was allowed into the United States. I took advantage of all the educational resources in this land of opportunity. I graduated valedictorian of my high school class and earned a four-year scholarship to Rutgers University, where I obtained a Bachelor of Science degree. I went on to earn a Master's degree from the University of Connecticut and finally a PhD from the University of Illinois. Within two months after graduating from Illinois, I was hired as an assistant professor of nutritional biochemistry at Rutgers, where I enjoyed a most productive research and teaching career. My PhD research involved tryptophan and niacin metabolism in the chick, and upon arrival at Rutgers I continued amino acid studies with the goal of assessing the essential amino acid requirements for egg production. This research was crowned with success and was followed with amino acid requirement studies for maintenance and for growth in rabbits, and ultimately with a reevaluation of requirements in adult humans. An outgrowth of the maintenance requirements led to a series of investigations into the metabolism of histidine, histamine, and carnosine (a histidine-containing dipeptide). Histamine, we found

  12. Plasma Tryptophan and the Kynurenine–Tryptophan Ratio Are Associated with the Acquisition of Statural Growth Deficits and Oral Vaccine Underperformance in Populations with Environmental Enteropathy

    Science.gov (United States)

    Kosek, Margaret N.; Mduma, Estomih; Kosek, Peter S.; Lee, Gwenyth O.; Svensen, Erling; Pan, William K. Y.; Olortegui, Maribel Paredes; Bream, Jay H.; Patil, Crystal; Asayag, Cesar Ramal; Sanchez, Graciela Meza; Caulfield, Laura E.; Gratz, Jean; Yori, Pablo Peñataro

    2016-01-01

    Early childhood enteric infections have adverse impacts on child growth and can inhibit normal mucosal responses to oral vaccines, two critical components of environmental enteropathy. To evaluate the role of indoleamine 2,3-dioxygenase 1 (IDO1) activity and its relationship with these outcomes, we measured tryptophan and the kynurenine–tryptophan ratio (KTR) in two longitudinal birth cohorts with a high prevalence of stunting. Children in rural Peru and Tanzania (N = 494) contributed 1,251 plasma samples at 3, 7, 15, and 24 months of age and monthly anthropometrics from 0 to 36 months of age. Tryptophan concentrations were directly associated with linear growth from 1 to 8 months after biomarker assessment. A 1-SD increase in tryptophan concentration was associated with a gain in length-for-age Z-score (LAZ) of 0.17 over the next 6 months in Peru (95% confidence interval [CI] = 0.11–0.23, P < 0.001) and a gain in LAZ of 0.13 Z-scores in Tanzania (95% CI = 0.03–0.22, P = 0.009). Vaccine responsiveness data were available for Peru only. An increase in kynurenine by 1 μM was associated with a 1.63 (95% CI = 1.13–2.34) increase in the odds of failure to poliovirus type 1, but there was no association with tetanus vaccine response. A KTR of 52 was 76% sensitive and 50% specific in predicting failure of response to serotype 1 of the oral polio vaccine. KTR was associated with systemic markers of inflammation, but also interleukin-10, supporting the association between IDO1 activity and immunotolerance. These results strongly suggest that the activity of IDO1 is implicated in the pathophysiology of environmental enteropathy, and demonstrates the utility of tryptophan and kynurenine as biomarkers for this syndrome, particularly in identifying those at risk for hyporesponsivity to oral vaccines. PMID:27503512

  13. Extracorporeal Treatment for Lithium Poisoning

    DEFF Research Database (Denmark)

    Decker, Brian S; Goldfarb, David S; Dargan, Paul I

    2015-01-01

    The Extracorporeal Treatments in Poisoning Workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments in poisoning. Here, the EXTRIP workgroup presents its recommendations for lithium poisoning. After a systematic literature search, clinical and toxico......The Extracorporeal Treatments in Poisoning Workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments in poisoning. Here, the EXTRIP workgroup presents its recommendations for lithium poisoning. After a systematic literature search, clinical...... extraction of patient-level data. The workgroup concluded that lithium is dialyzable (Level of evidence=A) and made the following recommendations: Extracorporeal treatment is recommended in severe lithium poisoning (1D). Extracorporeal treatment is recommended if kidney function is impaired and the [Li...... treatment (1D), but continuous RRT is an acceptable alternative (1D). The workgroup supported the use of extracorporeal treatment in severe lithium poisoning. Clinical decisions on when to use extracorporeal treatment should take into account the [Li(+)], kidney function, pattern of lithium toxicity...

  14. Aqueous lithium air batteries

    Energy Technology Data Exchange (ETDEWEB)

    Visco, Steven J.; Nimon, Yevgeniy S.; De Jonghe, Lutgard C.; Petrov, Alexei; Goncharenko, Nikolay

    2017-05-23

    Aqueous Li/Air secondary battery cells are configurable to achieve high energy density and prolonged cycle life. The cells include a protected a lithium metal or alloy anode and an aqueous catholyte in a cathode compartment. The aqueous catholyte comprises an evaporative-loss resistant and/or polyprotic active compound or active agent that partakes in the discharge reaction and effectuates cathode capacity for discharge in the acidic region. This leads to improved performance including one or more of increased specific energy, improved stability on open circuit, and prolonged cycle life, as well as various methods, including a method of operating an aqueous Li/Air cell to simultaneously achieve improved energy density and prolonged cycle life.

  15. Wetting properties of liquid lithium on lithium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Krat, S.A., E-mail: stepan.krat@gmail.com [Center for Plasma Material Interactions, Department of Nuclear, Plasma, and Radiological Engineering, University Illinois at Urbana-Champaign, Urbana (United States); National Research Nuclear University MEPhI, Moscow (Russian Federation); Popkov, A.S. [Center for Plasma Material Interactions, Department of Nuclear, Plasma, and Radiological Engineering, University Illinois at Urbana-Champaign, Urbana (United States); National Research Nuclear University MEPhI, Moscow (Russian Federation); Gasparyan, Yu. M.; Pisarev, A.A. [National Research Nuclear University MEPhI, Moscow (Russian Federation); Fiflis, Peter; Szott, Matthew; Christenson, Michael; Kalathiparambil, Kishor; Ruzic, David N. [Center for Plasma Material Interactions, Department of Nuclear, Plasma, and Radiological Engineering, University Illinois at Urbana-Champaign, Urbana (United States)

    2017-04-15

    Highlights: • Contact angles of liquid lithium and Li{sub 3}N, Li{sub 2}O, Li{sub 2}CO{sub 3} were measured. • Liquid lithium wets lithium compounds at relatively low temperatures: Li{sub 3}N at 257 °C, Li{sub 2}O at 259 °C, Li{sub 2}CO{sub 3} at 323 °C. • Li wets Li{sub 2}O and Li{sub 3}N better than previously measured fusion-relevant materials (W, Mo, Ta, TZM, stainless steel). • Li wets Li{sub 2}CO{sub 3} better than most previously measured fusion-relevant materials (W, Mo, Ta). - Abstract: Liquid metal plasma facing components (LMPFC) have shown a potential to supplant solid plasma facing components materials in the high heat flux regions of magnetic confinement fusion reactors due to the reduction or elimination of concerns over melting, wall damage, and erosion. To design a workable LMPFC, one must understand how liquid metal interacts with solid underlying structures. Wetting is an important factor in such interaction, several designs of LMPFC require liquid metal to wet the underlying solid structures. The wetting of lithium compounds (lithium nitride, oxide, and carbonate) by 200 °C liquid lithium at various surface temperature from 230 to 330 °C was studied by means of contact angle measurements. Wetting temperatures, defined as the temperature above which the contact angle is less than 90°, were measured. The wetting temperature was 257 °C for nitride, 259 °C for oxide, and 323 °C for carbonate. Surface tensions of solid lithium compounds were calculated from the contact angle measurements.

  16. Grain Boundary Engineering of Lithium-Ion-Conducting Lithium Lanthanum Titanate for Lithium-Air Batteries

    Science.gov (United States)

    2016-01-01

    release; distribution is unlimited. 1 1. Introduction Lithium (Li)-ion batteries are currently one of the leading energy storage device technologies...phase) were submerged in concentrated LiCl solution. The LiCl solution was made by dissolving lithium carbonate (LiCO3) into hydrogen chloride until...Direct correlations between fracture toughness and grain boundary segregation behavior in ytterbium- doped magnesium aluminate spinel. Scripta

  17. Microenvironment of tryptophan residues in beta-lactoglobulin derivative polypeptide-sodium dodecyl sulfate complexes.

    Science.gov (United States)

    Imamura, T; Konishi, K

    1992-06-01

    The changes of microenvironment of tryptophan residues in beta-lactoglobulin A and its cyanogen bromide (CNBr) fragments with the binding of sodium dodecyl sulfate (SDS) were studied with measurements of the rates of N-bromosuccinimide (NBS) modification reactions by stopped-flow photometry. Two tryptophan residues of carboxyamidomethylated (RCM) beta-lactoglobulin A in the states of their complexes with SDS were clearly distinguishable by their differences in NBS modification rates. We confirmed by experiments with CNBr fragments containing trytophan residue. The modification rates of Trp 19 in RCM beta-lactoglobulin A-SDS complexes were about 10-fold smaller than those expected for tryptophan residues exposed entirely to the aqueous solvent. The Trp 61 was hardly changed. The change of rate constants for Trp 19 was virtually consistent with those observed when N-acetyl-L-trytophan ethylester was dissolved in SDS micelles. For various species of polypeptide-SDS complexes, all tryptophan residues were reactive to NBS and also, for some of them, the differences in NBS modification rates were observed between tryptophan residues on a common polypeptide chain. These results suggest micellar and heterogeneous bindings of SDS to polypeptides.

  18. Reaction pathway of tryptophanase-catalyzed L-tryptophan synthesis from D-serine.

    Science.gov (United States)

    Shimada, Akihiko; Ozaki, Haruka; Saito, Takeshi; Fujii, Noriko

    2011-11-01

    Tryptophanase, L-tryptophan indole-lyase with extremely absolute stereospecificity, can change the stereospecificity in concentrated diammonium hydrogenphosphate solution. While tryptophanase is not inert to D-serine in the absence of diammonium hydrogenphosphate, it can undergo L-tryptophan synthesis from D-serine along with indole in the presence of it. It has been well known that tryptophanase synthesizes L-tryptophan from L-serine through a β-substitution mechanism of the ping-pong type. However, a metabolic pathway of L-tryptophan synthesis from D-serine has remained unclear. The present study aims to elucidate it. Diammonium hydrogenphosphate plays a role in the emergence of catalytic activity on D-serine. The salt gives tryptophanase a small conformational change, which makes it possible to catalyze D-serine. Tryptophanase-bound D-serine produces L-tryptophan synthesis by β-replacement reaction via the enzyme-bound aminoacrylate intermediate. Our result will be valuable in studying the origin of homochirality.

  19. Lignans from Carthamus tinctorius suppress tryptophan breakdown via indoleamine 2,3-dioxygenase

    Science.gov (United States)

    Kuehnl, Susanne; Schroecksnadel, Sebastian; Temml, Veronika; Gostner, Johanna M.; Schennach, Harald; Schuster, Daniela; Schwaiger, Stefan; Rollinger, Judith M.; Fuchs, Dietmar; Stuppner, Hermann

    2013-01-01

    Seed extracts of Carthamus tinctorius L. (Asteraceae), safflower, have been traditionally used to treat coronary disease, thrombotic disorders, and menstrual problems but also against cancer and depression. A possible effect of C. tinctorius compounds on tryptophan-degrading activity of enzyme indoleamine 2,3-dioxygenase (IDO) could explain many of its activities. To test for an effect of C. tinctorius extracts and isolated compounds on cytokine-induced IDO activity in immunocompetent cells in vitro methanol and ethylacetate seed extracts were prepared from cold pressed seed cakes of C. tinctorius and three lignan derivatives, trachelogenin, arctigenin and matairesinol were isolated. The influence on tryptophan breakdown was investigated in peripheral blood mononuclear cells (PBMCs). Effects were compared to neopterin production in the same cellular assay. Both seed extracts suppressed tryptophan breakdown in stimulated PBMC. The three structurally closely related isolates exerted differing suppressive activity on PBMC: arctigenin (IC50 26.5 μM) and trachelogenin (IC50 of 57.4 μM) showed higher activity than matairesinol (IC50 >200 μM) to inhibit tryptophan breakdown. Effects on neopterin production were similar albeit generally less strong. Data show an immunosuppressive property of compounds which slows down IDO activity. The in vitro results support the view that some of the anti-inflammatory, anti-cancer and antidepressant properties of C. tinctorius lignans might relate to their suppressive influence on tryptophan breakdown. PMID:23867649

  20. Mutagenesis of tryptophan199 suggests that hopping is required for MauG-dependent tryptophan tryptophylquinone biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Tarboush, Nafez Abu; Jensen, Lyndal M.R.; Yukl, Erik T.; Geng, Jiafeng; Liu, Aimin; Wilmot, Carrie M.; Davidson, Victor L. (Central Florida); (GSU); (UMMC); (UMM)

    2011-12-07

    The diheme enzyme MauG catalyzes the posttranslational modification of the precursor protein of methylamine dehydrogenase (preMADH) to complete biosynthesis of its protein-derived tryptophan tryptophylquinone (TTQ) cofactor. Catalysis proceeds through a high valent bis-Fe(IV) redox state and requires long-range electron transfer (ET), as the distance between the modified residues of preMADH and the nearest heme iron of MauG is 19.4 {angstrom}. Trp199 of MauG resides at the MauG-preMADH interface, positioned midway between the residues that are modified and the nearest heme. W199F and W199K mutations did not affect the spectroscopic and redox properties of MauG, or its ability to stabilize the bis-Fe(IV) state. Crystal structures of complexes of W199F/K MauG with preMADH showed no significant perturbation of the MauG-preMADH structure or protein interface. However, neither MauG variant was able to synthesize TTQ from preMADH. In contrast, an ET reaction from diferrous MauG to quinone MADH, which does not require the bis-Fe(IV) intermediate, was minimally affected by the W199F/K mutations. W199F/K MauGs were able to oxidize quinol MADH to form TTQ, the putative final two-electron oxidation of the biosynthetic process, but with k{sub cat}/K{sub m} values approximately 10% that of wild-type MauG. The differential effects of the W199F/K mutations on these three different reactions are explained by a critical role for Trp199 in mediating multistep hopping from preMADH to bis-Fe(IV) MauG during the long-range ET that is required for TTQ biosynthesis.

  1. High performance discharges in the Lithium Tokamak eXperiment with liquid lithium wallsa)

    Science.gov (United States)

    Schmitt, J. C.; Bell, R. E.; Boyle, D. P.; Esposti, B.; Kaita, R.; Kozub, T.; LeBlanc, B. P.; Lucia, M.; Maingi, R.; Majeski, R.; Merino, E.; Punjabi-Vinoth, S.; Tchilingurian, G.; Capece, A.; Koel, B.; Roszell, J.; Biewer, T. M.; Gray, T. K.; Kubota, S.; Beiersdorfer, P.; Widmann, K.; Tritz, K.

    2015-05-01

    The first-ever successful operation of a tokamak with a large area (40% of the total plasma surface area) liquid lithium wall has been achieved in the Lithium Tokamak eXperiment (LTX). These results were obtained with a new, electron beam-based lithium evaporation system, which can deposit a lithium coating on the limiting wall of LTX in a five-minute period. Preliminary analyses of diamagnetic and other data for discharges operated with a liquid lithium wall indicate that confinement times increased by 10× compared to discharges with helium-dispersed solid lithium coatings. Ohmic energy confinement times with fresh lithium walls, solid and liquid, exceed several relevant empirical scaling expressions. Spectroscopic analysis of the discharges indicates that oxygen levels in the discharges limited on liquid lithium walls were significantly reduced compared to discharges limited on solid lithium walls. Tokamak operations with a full liquid lithium wall (85% of the total plasma surface area) have recently started.

  2. Multi-layered, chemically bonded lithium-ion and lithium/air batteries

    Energy Technology Data Exchange (ETDEWEB)

    Narula, Chaitanya Kumar; Nanda, Jagjit; Bischoff, Brian L; Bhave, Ramesh R

    2014-05-13

    Disclosed are multilayer, porous, thin-layered lithium-ion batteries that include an inorganic separator as a thin layer that is chemically bonded to surfaces of positive and negative electrode layers. Thus, in such disclosed lithium-ion batteries, the electrodes and separator are made to form non-discrete (i.e., integral) thin layers. Also disclosed are methods of fabricating integrally connected, thin, multilayer lithium batteries including lithium-ion and lithium/air batteries.

  3. Multi-layered, chemically bonded lithium-ion and lithium/air batteries

    Science.gov (United States)

    Narula, Chaitanya Kumar; Nanda, Jagjit; Bischoff, Brian L; Bhave, Ramesh R

    2014-05-13

    Disclosed are multilayer, porous, thin-layered lithium-ion batteries that include an inorganic separator as a thin layer that is chemically bonded to surfaces of positive and negative electrode layers. Thus, in such disclosed lithium-ion batteries, the electrodes and separator are made to form non-discrete (i.e., integral) thin layers. Also disclosed are methods of fabricating integrally connected, thin, multilayer lithium batteries including lithium-ion and lithium/air batteries.

  4. Sealed Primary Lithium-Inorganic Electrolyte Cell

    Science.gov (United States)

    1977-02-01

    Battery , Thionyl Chloride , Lithium , Lithium Aluminum Chloride , Hermetic Lithium Battery , D Cell, Voltage-Delay, Shelf Life, High Energy Density Battery ... lithium - thionyl chloride , inorganic electrclyte system is one of the highest energy density systems known to date (1-4). The cells contain an Li anoae, a...However, this is not tne case with te thionyl chloride system. A completely discharged battery , while sitting on

  5. Lithium Ion Battery Anode Aging Mechanisms

    Directory of Open Access Journals (Sweden)

    Victor Agubra

    2013-03-01

    Full Text Available Degradation mechanisms such as lithium plating, growth of the passivated surface film layer on the electrodes and loss of both recyclable lithium ions and electrode material adversely affect the longevity of the lithium ion battery. The anode electrode is very vulnerable to these degradation mechanisms. In this paper, the most common aging mechanisms occurring at the anode during the operation of the lithium battery, as well as some approaches for minimizing the degradation are reviewed.

  6. Lithium Ion Battery Anode Aging Mechanisms

    OpenAIRE

    Victor Agubra; Jeffrey Fergus

    2013-01-01

    Degradation mechanisms such as lithium plating, growth of the passivated surface film layer on the electrodes and loss of both recyclable lithium ions and electrode material adversely affect the longevity of the lithium ion battery. The anode electrode is very vulnerable to these degradation mechanisms. In this paper, the most common aging mechanisms occurring at the anode during the operation of the lithium battery, as well as some approaches for minimizing the degradation are reviewed.

  7. Novel Electrolytes for Lithium Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lucht, Brett L. [Univ. of Rhode Island, Kingston, RI (United States). Dept. of Chemistry

    2014-12-12

    We have been investigating three primary areas related to lithium ion battery electrolytes. First, we have been investigating the thermal stability of novel electrolytes for lithium ion batteries, in particular borate based salts. Second, we have been investigating novel additives to improve the calendar life of lithium ion batteries. Third, we have been investigating the thermal decomposition reactions of electrolytes for lithium-oxygen batteries.

  8. Lithium. Effects on excitable cell membranes

    NARCIS (Netherlands)

    Ploeger, Egbert Johan

    1974-01-01

    LITHIUM: Effects on excitable cell membranes. Lithium salts have been used in the treatment of manic-depressive psychosis for many years but their mechanism of action is not well understood. Many workers assume that the action of lithium on catecholamine metabolism and/or on electrolyte distribution

  9. Phase transition in a rechargeable lithium battery

    NARCIS (Netherlands)

    Dreyer, W.; Gaberscek, M.; Guhlke, C.; Huth, R.; Jamnik, J.

    We discuss the lithium storage process within a single-particle cathode of a lithium-ion battery. The single storage particle consists of a crystal lattice whose interstitial lattice sites may be empty or reversibly filled with lithium atoms. The resulting evolution equations describe diffusion with

  10. 77 FR 28259 - Mailings of Lithium Batteries

    Science.gov (United States)

    2012-05-14

    ... quantity, size, watt hours, and whether the cells or batteries are packed in equipment, with equipment, or... 111 Mailings of Lithium Batteries AGENCY: Postal Service TM . ACTION: Final rule. SUMMARY: The Postal... batteries and devices containing lithium batteries. This prohibition also extends to the mailing of lithium...

  11. Phase transition in a rechargeable lithium battery

    NARCIS (Netherlands)

    Dreyer, W.; Gaberscek, M.; Guhlke, C.; Huth, R.; Jamnik, J.

    2011-01-01

    We discuss the lithium storage process within a single-particle cathode of a lithium-ion battery. The single storage particle consists of a crystal lattice whose interstitial lattice sites may be empty or reversibly filled with lithium atoms. The resulting evolution equations describe diffusion with

  12. Anode materials for lithium-ion batteries

    Science.gov (United States)

    Sunkara, Mahendra Kumar; Meduri, Praveen; Sumanasekera, Gamini

    2014-12-30

    An anode material for lithium-ion batteries is provided that comprises an elongated core structure capable of forming an alloy with lithium; and a plurality of nanostructures placed on a surface of the core structure, with each nanostructure being capable of forming an alloy with lithium and spaced at a predetermined distance from adjacent nanostructures.

  13. Phase transition in a rechargeable lithium battery

    NARCIS (Netherlands)

    Dreyer, W.; Gaberscek, M.; Guhlke, C.; Huth, R.; Jamnik, J.

    2011-01-01

    We discuss the lithium storage process within a single-particle cathode of a lithium-ion battery. The single storage particle consists of a crystal lattice whose interstitial lattice sites may be empty or reversibly filled with lithium atoms. The resulting evolution equations describe diffusion with

  14. Tryptophan metabolism in tsetse flies and the consequences of its derangement

    Directory of Open Access Journals (Sweden)

    R. H. Gooding

    1987-01-01

    Full Text Available Literature comparing salmon and wild type Glossina morsitans morsitans and that comparing tan and wild type Glossina palpalis palpalis is reviewed. New information is presented on behaviour and biochemistry of salmon and wild type G. m. morsitans. The eye color mutants result from two lesions in the tryptophan to xanthommatin pathway: lack of tryptophan oxygenase in G. m morsitans and failure to produce or retain xanthommatin in eyes (but not in testes of G. p. palpalis. The salmon allele in G. m. morsitans is pleiotropic and profoundly affects many aspects of fly biology including longevity, reproductive capacity, vision, vectorial capacity and duration of flight, but not circadian rhythms. The tan allele in G. p. palpalis has little effect upon the biology of flies under laboratory conditions, except that tan flies appear less active than normal. Adult tsetse flies metabolize tryptophan to kynurenine which is excreted; fluctuations in activities of the enzymes producing kynurenine suggest this pathway is under metabolic control.

  15. Effect of tryptophan suplementation in quails (Coturnix coturnix japónica

    Directory of Open Access Journals (Sweden)

    Liliana Betancourt López

    2005-05-01

    Full Text Available The behaviour and productive parameters of 288 quails (Coturnix coturnix japonica were studied in a commercial farm. They were supplemented with tryptophan as a precursor of the neurotransmitter serotonin. Levels of 0 (T1, 1,25 mg/day (T2 and 2,5 mg/day (T3. The control group showed a higher number of birds (P<0,05 with an aggressive position before an external stimulus. This study proves that tryphtophan decreases aggression and stabilizes social behaviour. Similarly, the number of birds with moulted backs was higher in the witness group. During the evaluation period a higher egg weight was observed along with improved food conversion and a higher weight gain in the groups supplemented with tryptophan clearly showing the positive effect of tryptophan.

  16. Determination of epristeride by its quenching effect on the fluorescence of L-tryptophan

    Institute of Scientific and Technical Information of China (English)

    Ai-Qin Gong; Xia-Shi Zhu

    2013-01-01

    A rapid, novel spectrofluorimetric method to determine epristeride (EP) in biological fluids and a pharmaceutical formulation was developed, based on the fact that fluorescence intensity of L-tryptophan could be quenched by EP in the medium of pH ¼ 9.0. The various factors influencing fluorescence quenching were discussed. The quenching mechanism was investigated with the quenching type, synchronous fluorescence spectra and quantum efficiency. Under the optimized conditions, fluorescence quenching value (ΔF ¼ FL-tryptophan-FEP-L-tryptophan) showed a good linear relationship with the EP concentration ranging from 0.4 to 12.0μg/mL. The linearity, recovery and limit of detection demonstrated that the proposed method was suitable for EP determination in biological fluids and EP tablets. The method was successfully applied to the analysis of EP in real samples and the obtained results were in good agreement with the results of the official method.

  17. Adsorption of the Enantiomers of Tryptophan on Stationary Phase Bonded with Bovine Serum Albumin

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fengbao; CHENG Ming; LI Shuang; LIU Liang; ZHANG Guoliang

    2006-01-01

    Frontal analysis is frequently applied to measuring single or multi-component adsorption isotherms. In this work, the competitive adsorption isotherm data of two enantiomers of tryptophan were obtained by competitive frontal analysis. The stationary phase in the column was silica-immobilized bovine serum albumin(BSA)by the derivative method, and the mobile phase was a phosphate buffer. These isotherm data were fitted by the competitive Bilangmuir model. This model can account for the behavior of both tryptophan enantiomers and these profiles were found to fit the experimental band profiles(square error is 0.999 6). The parameters obtained were used in numericai calculations to predict the band profiles of the racemic mixtures of tryptophan. The equilibriumdispersive model provides satisfactory prediction, with minor differences between the calculated and the experimental profiles.

  18. The crystal structure of tryptophan hydroxylase with bound amino acid substrate

    DEFF Research Database (Denmark)

    Windahl, Michael Skovbo; Petersen, Charlotte Rode; Christensen, Hans Erik Mølager

    2008-01-01

    124−Asp139 and Ile367−Thr369 close around the active site. Similar structural changes are seen in the catalytic domain of phenylalanine hydroxylase (PAH) upon binding of substrate analogues norleucine and thienylalanine to the PAH·BH4 complex. In fact, the chicken TPH1·Trp·imidazole structure......Tryptophan hydroxylase (TPH) is a mononuclear non-heme iron enzyme, which catalyzes the reaction between tryptophan, O2, and tetrahydrobiopterin (BH4) to produce 5-hydroxytryptophan and 4a-hydroxytetrahydrobiopterin. This is the first and rate-limiting step in the biosynthesis...... of the neurotransmitter and hormone serotonin (5-hydroxytryptamine). We have determined the 1.9 Å resolution crystal structure of the catalytic domain (Δ1−100/Δ415−445) of chicken TPH isoform 1 (TPH1) in complex with the tryptophan substrate and an iron-bound imidazole. This is the first structure of any aromatic amino...

  19. Flow-injection chemiluminescence determination of tryptophan using galangin-potassium permanganate-polyphosphoric acid system

    Institute of Scientific and Technical Information of China (English)

    Hui Chen; Li Li; Min Zhou; Yong Jun Ma

    2008-01-01

    A high sensitive flow-injection chemiluminescence (FI-CL)method for the determination of tryptephan has been developed.The method is based on the chemiluminescence reaction of galangin-potassium perrnanganate-tryptophan in polyphosphoric acid (PPA)media.Under the optimized conditions,tryptophan was determined in the range 0.05-10 μg/mL with the detection limit (30)of 5.0× 10-3 μg/mL.The relative standard deviation (RSD)was 1.0% for 11 replicate determinations of 1.0 μg/mL tryptophan.Three synthetic samples were determined selectively with recoveries in the range from 99.6% to 102.0% in the presence of other amino acids.

  20. Space-charge at the lithium-lithium chloride interface

    Science.gov (United States)

    Jamnik, J.; Gaberscek, M.; Meden, A.; Pejovnik, S.

    1991-06-01

    The electrical properties of the passive layer formed on lithium as the product of the corrosion reaction in thionyl chloride are discussed. The passive layer is regarded as a thin layer of an ionic crystal placed between two party blocking electrodes (i.e., lithium and liquid electrolyte). After a short review of thermodynamic properties of the system, a model for description of the electric properties of the static space-charge regions is presented. On this basis, a comment on and partial reinterpretation of impedance measurements of the passive layer is given. The suggested approach leads to the conclusion that the quality of Li/SOCl2 batteries decisively depends on the properties of the lithium passive layer interface. Finally, experiments to confirm the model are suggested.

  1. Lithium batteries in Japan; Les batteries lithium au Japon

    Energy Technology Data Exchange (ETDEWEB)

    Guyomard, D.; Mercier, A.; Tarascon, J.M.

    2000-04-01

    This document is a mission report about the development of lithium batteries research in Japan. The mission took place between November 29 and December 3, 1999 and was organized by the Science and Technology Service of the French embassy in Tokyo. The organizations shown during the mission were: ETL, NEDO/LIBES, the Kyoto university, Yuasa, Hitachi, Matsushita, Japan Storage, Sanyo and Sony. The mission has shown that the government program is clearly backward. The Japanese research on battery materials remains important. The leaders of the lithium-ion technology are Sony, first, and then Hitachi and Sanyo. Applications of lithium-ion batteries are developing for small electric-powered vehicles. (J.S.)

  2. Effects of lithium chloride on outward potassium currents in acutely isolated hippocampal CA1 pyramidal neurons

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chaofeng; DU Huizhi; YANG Pin

    2006-01-01

    Although lithium possesses neuroprotective functions, the molecular mechanism underlying its actions has not been fully elucidated. In the present paper, the effects of lithium chloride on voltage-dependent potassium currents in the CA1 pyramidal neurons acutely isolated from rat hippocampus were studied using the whole-cell patch-clamp technique. Depolarizing test pulses activated two components of outward potassium currents: a rapidly activating and inactivating component, IA and a delayed component, IK. Results showed that lithium chloride increased the amplitude of IA in a concentration-dependent manner. Half enhancement concentration (EC50) was 22.80±5.45 μmol·L-1. Lithium chloride of 25 μmol·L-1 shifted the steady-state activation curve and inactivation curve of IA to more negative potentials, but mainly affected the activation kinetics. The amplitude and the activation processes of IK were not affected by lithium chloride. The effects of lithium chloride on potassium channel appear to possess neuroprotective properties by Ca2+-lowing effects modulate neuronal excitability by activating IA in rat hippocampal neurons.

  3. Lithium-Associated Kidney Microcysts

    Directory of Open Access Journals (Sweden)

    Jennifer Tuazon

    2008-01-01

    Full Text Available Long-term lithium therapy is associated with impairment in concentrating ability and, occasionally, progression to advanced chronic kidney disease from tubulointerstitial nephropathy. Biopsy findings in patients with lithium-induced chronic tubulointerstitial nephropathy include tubular atrophy and interstitial fibrosis interspersed with tubular cysts and dilatations. Recent studies have shown that cysts are seen in 33––62.5% of the patients undergoing lithium therapy. MR imaging is highly capable of defining renal morphological features and has been demonstrated to be superior to US and CT scan for the visualization of small renal cysts. The microcysts are found in both cortex and medulla, particularly in the regions with extensive atrophy and fibrosis, and can be multiple and bilateral. They tend to be sparse and do not normally exceed 1–2 mm in diameter. The renal microcysts in the image here reported are subtle, but consistent with lithium-induced chronic nephropathy. An MRI of the kidneys provides noninvasive evidence that strengthens the diagnosis of lithium-induced nephropathy.

  4. Lithium-associated kidney microcysts.

    Science.gov (United States)

    Tuazon, Jennifer; Casalino, David; Syed, Ehteshamuddin; Batlle, Daniel

    2008-08-31

    Long-term lithium therapy is associated with impairment in concentrating ability and, occasionally, progression to advanced chronic kidney disease from tubulointerstitial nephropathy. Biopsy findings in patients with lithium-induced chronic tubulointerstitial nephropathy include tubular atrophy and interstitial fibrosis interspersed with tubular cysts and dilatations. Recent studies have shown that cysts are seen in 33-62.5% of the patients undergoing lithium therapy. MR imaging is highly capable of defining renal morphological features and has been demonstrated to be superior to US and CT scan for the visualization of small renal cysts. The microcysts are found in both cortex and medulla, particularly in the regions with extensive atrophy and fibrosis, and can be multiple and bilateral. They tend to be sparse and do not normally exceed 1-2 mm in diameter. The renal microcysts in the image here reported are subtle, but consistent with lithium-induced chronic nephropathy. An MRI of the kidneys provides noninvasive evidence that strengthens the diagnosis of lithium-induced nephropathy.

  5. Lithium as a blanket coolant

    Energy Technology Data Exchange (ETDEWEB)

    Wells, W.M.

    1977-01-01

    Recent re-assessment of tokamak reactors which move towards smaller size and lower required field strength (higher beta)/sup 2/ change the picture as regards the magnitude of MHD effects on flow resistance for lithium coolant. Perhaps the most important consequence of this as regards use of this coolant is that of clear acceptability of such effects when the flow is predominantly transverse to the magnetic field. This permits defining a blanket that consists entirely of round tubes containing the circulated lithium with voids between the tubes. Required thermal-hydraulic calculations are then on bases which are well established, especially in view of recent results dealing with perturbations of ducts and magnetic fields. Mitigation of MHD effects is feasible through tapering of tube wall thickness or use of insulated layers, but their use was not mandatory for the assumed conditions. Blanket configurations utilizing flowing lithium in round tubes immersed in static lithium may be suitable, but calculational methods do not now exist for this situation. Use of boiling potassium or cesium appears to be prohibitive in terms of vapor flow area when temperature levels are consistent with stainless steel. Liquid sodium, in addition to not being a breeding material, requires higher velocity than lithium for the same heat removal.

  6. Development of the water cooled lithium lead blanket for DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, J., E-mail: julien.aubert@cea.fr [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Aiello, G.; Jonquères, N. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Li Puma, A. [CEA-Saclay, DEN/DANS/DM2S/SERMA/LPEC, 91191 Gif Sur Yvette Cedex (France); Morin, A.; Rampal, G. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France)

    2014-10-15

    Highlights: • The WCLL blanket design has been modified to adapt it to the 2012 EFDA DEMO specifications. • Preliminary CAD design of the equatorial outboard module of the WCLL blanket has been developed for DEMO. • Finite elements analyses have been carried out in order to assess the module thermal behavior in the straight part of the module. - Abstract: The water cooled lithium lead (WCLL) blanket, based on near-future technology requiring small extrapolation from present-day knowledge both on physical and technological aspect, is one of the breeding blanket concepts considered as possible candidates for the EU DEMOnstration power plant. In 2012, the EFDA agency issued new specifications for DEMO: this paper describes the work performed to adapt the WCLL blanket design to those specifications. Relatively small modules with straight surfaces are attached to a common Back Supporting Structure housing feeding pipes. Each module features reduced activation ferritic-martensitic steel as structural material, liquid Lithium-Lead as breeder, neutron multiplier and carrier. Water at typical Pressurized Water Reactors (PWR) conditions is chosen as coolant. A preliminary design of the equatorial outboard module has been achieved. Finite elements analyses have been carried out in order to assess the module thermal behavior. Two First Wall (FW) concepts have been proposed, one favoring the thermal efficiency, the other favoring the manufacturability. The Breeding Zone has been designed with C-shaped Double-Walled Tubes in order to minimize the Water/Pb-15.7Li interaction likelihood. The priorities for further development of the WCLL blanket concept are identified in the paper.

  7. The crystal structure of tryptophan hydroxylase with bound amino acid substrate

    DEFF Research Database (Denmark)

    Windahl, Michael Skovbo; Petersen, Charlotte Rode; Christensen, Hans Erik Mølager

    2008-01-01

    acid hydroxylase with bound natural amino acid substrate. The iron coordination can be described as distorted trigonal bipyramidal coordination with His273, His278, and Glu318 (partially bidentate) and one imidazole as ligands. The tryptophan stacks against Pro269 with a distance of 3.9 Å between...... of the neurotransmitter and hormone serotonin (5-hydroxytryptamine). We have determined the 1.9 Å resolution crystal structure of the catalytic domain (Δ1−100/Δ415−445) of chicken TPH isoform 1 (TPH1) in complex with the tryptophan substrate and an iron-bound imidazole. This is the first structure of any aromatic amino...

  8. Tryptophan-Ethylester, the False (Unveiled) Melatonin Isomer in Red Wine

    Science.gov (United States)

    Iriti, Marcello; Vigentini, Ileana

    2015-01-01

    Among the food plants, the presence of melatonin in grapes (Vitis vinifera L.) deserves particular attention because of the production of wine, an alcoholic beverage of economic relevance and with putative healthy effects. Furthermore, melatonin isomers have been detected in wine too. Recently, one of these isomers has been identified as tryptophan-ethylester, a compound with the same molecular weight of melatonin. In this Commentary, we briefly comment the source(s) of tryptophan-ethylester in wine and the putative nutritional role(s). PMID:25922582

  9. [Nature of tryptophan photooxidation products in lysozyme in the presence of methylene blue].

    Science.gov (United States)

    Churakova, N I; Kravchenko, N A; Serebriakov, E P; Kaverzneva, E D

    1976-05-01

    One out of six trytophan residues in two lysozyme modification, obtained under lysozyme photooxidation in the presence of methylene blue, is found to be oxidized to N'-formylkinurenine (in one modification) and to kinurenine (in the other modification). The transition of one modification into another via detaching of N'-formyl group by soft acid hydrolysis has shown that one and the same tryptophan residue is oxidized in both products, Possible mechanism of tryptophan oxidation to the products mentioned is discu-sed on the basis of the hypothesis on signlet mechanism of lysozyme photooxidation in the presence of methylene blue.

  10. Studies on the biotin-binding site of avidin. Tryptophan residues involved in the active site.

    Science.gov (United States)

    Gitlin, G; Bayer, E A; Wilchek, M

    1988-01-01

    Egg-white avidin was modified with the tryptophan-specific reagent 2-hydroxy-5-nitrobenzyl bromide. The complete loss of biotin-binding activity was achieved upon modification of an average of one tryptophan residue per avidin subunit. The identity of the modified residues was determined by isolating the relevant tryptic and chymotryptic peptides from CNBr-cleaved avidin fragments. The results demonstrate that Trp-70 and Trp-110 are modified in approximately equivalent proportions. It is believed that these residues are located in the active site of avidin and take part in the binding of biotin. PMID:3355517

  11. Studies on the biotin-binding site of avidin. Tryptophan residues involved in the active site.

    Science.gov (United States)

    Gitlin, G; Bayer, E A; Wilchek, M

    1988-02-15

    Egg-white avidin was modified with the tryptophan-specific reagent 2-hydroxy-5-nitrobenzyl bromide. The complete loss of biotin-binding activity was achieved upon modification of an average of one tryptophan residue per avidin subunit. The identity of the modified residues was determined by isolating the relevant tryptic and chymotryptic peptides from CNBr-cleaved avidin fragments. The results demonstrate that Trp-70 and Trp-110 are modified in approximately equivalent proportions. It is believed that these residues are located in the active site of avidin and take part in the binding of biotin.

  12. 6-Nitro-L-tryptophan: a novel spectroscopic probe of trp aporepressor and human serum albumin.

    Science.gov (United States)

    Phillips, R S; Marmorstein, R Q

    1988-04-01

    The binding of 6-nitro-L-tryptophan to trp aporepressor and human serum albumin has been examined by visible difference spectroscopy and circular dichroism. 6-Nitro-L-tryptophan, prepared by nitration of L-tryptophan with nitric acid in glacial acetic acid, exhibits a visible and near-uv absorption spectrum with lambda max at about 330 nm (epsilon = 7 X 10(3) M-1 cm-1) and a shoulder near 380 nm in H2O. In the presence of trp aporepressor, the visible absorption intensity is sharply diminished. Visible difference spectral titration data give KD = 1.27 X 10(-4) M and n = 0.95 per subunit at 25 degrees C. While 6-nitro-L-tryptophan exhibits no significant circular dichroism between 300 and 500 nm, the complex with trp aporepressor exhibits strong circular dichroism signals, with a negative maximum at 386 nm (delta epsilon = -7.5 M-1 cm-1) and a positive maximum at 310 nm (delta epsilon = +6 M-1 cm-1). Circular dichroism titration data give KD = 1.69 X 10(-4) M and n = 0.90 per subunit at 25 degrees C. The KD values determined spectroscopically are in excellent agreement with that determined by equilibrium dialysis, KD = 1.5 X 10(-4) M at 25 degrees C. In the presence of human serum albumin, the spectrum of 6-nitro-L-tryptophan exhibits a blue shift and an increase in absorption intensity; similar changes are observed in solvents of low dielectric contrast such as 80% aqueous dioxane. Visible difference spectral titration data give KD = 8.0 X 10(-5) M and n = 0.95 for human serum albumin. The complex of 6-nitro-L-tryptophan with human serum albumin exhibits a strong positive circular dichroism maximum at 380 nm (delta epsilon = +9.8 M-1 cm-1) with a shoulder at 310-320 nm. Circular dichroism titration data give KD = 6.4 X 10(-5) M and n = 0.83, in good agreement with the visible difference spectral results. Taken together, our results demonstrate the utility of 6-nitro-L-tryptophan as a spectroscopic probe for tryptophan-binding proteins.

  13. Electrolytes for lithium and lithium-ion batteries

    CERN Document Server

    Jow, T Richard; Borodin, Oleg; Ue, Makoto

    2014-01-01

    Electrolytes for Lithium and Lithium-ion Batteries provides a comprehensive overview of the scientific understanding and technological development of electrolyte materials in the last?several years. This book covers key electrolytes such as LiPF6 salt in mixed-carbonate solvents with additives for the state-of-the-art Li-ion batteries as well as new electrolyte materials developed recently that lay the foundation for future advances.?This book also reviews the characterization of electrolyte materials for their transport properties, structures, phase relationships, stabilities, and impurities.

  14. Adsorption of the cysteine–tryptophan dipeptide at the Au(110)/liquid interface studied using reflection anisotropy spectroscopy

    DEFF Research Database (Denmark)

    Morozzo della Rocca, Blasco; Smith, C I; Tesauro, Cinzia

    2010-01-01

    failed to re-establish the initial population of Au–S bonds and the changes induced in the region of the spectrum associated with the tryptophan's by the positive potentials were permanent on the time scale of an hour. Subtle changes associated with the tryptophan moieties indicate that the orientation...

  15. Fluorescent differentiation and quantificational detection of free tryptophan in serum within a confined metal-organic tetrahedron.

    Science.gov (United States)

    He, Cheng; Wang, Jian; Wu, Pengyan; Jia, Lingyun; Bai, Ying; Zhang, Zhichao; Duan, Chunying

    2012-12-18

    A metal-organic cerium tetrahedron having size constraints and cooperated interactions within its cavity was used to selectively recognize tryptophan over other natural amino acids and Trp-containing peptides. It was applied in quantificational detection of free tryptophan in serum.

  16. Research on lithium batteries

    Science.gov (United States)

    Hill, I. R.; Goledzinowski, M.; Dore, R.

    1993-12-01

    Research was conducted on two types of lithium batteries. The first is a rechargeable Li-SO2 system using an all-inorganic electrolyte. A Li/liquid cathode system was chosen to obtain a relatively high discharge rate capability over the +20 to -30 C range. The fabrication and cycling performance of research cells are described, including the preparation and physical properties of porous polytetra fluoroethylene bonded carbon electrodes. Since the low temperature performance of the standard electrolyte was unsatisfactory, studies of electrolytes containing mixed salts were made. Raman spectroscopy was used to study the species present in these electrolytes and to identify discharge products. Infrared spectroscopy was used to measure electrolyte impurities. Film growth on the LiCl was also monitored. The second battery is a Li-thionyl chloride nonrechargeable system. Research cells were fabricated containing cobalt phthalo cyanine in the carbon cathode. The cathode was heat treated at different temperatures and the effect on cell discharge rate and capacity evaluated. Commercially obtained cells were used in an investigation of a way to identify substandard cells. The study also involved electrochemical impedance spectroscopy and cell discharging at various rates. The results are discussed in terms of LiCl passivation.

  17. Twenty-four-hour plasma tryptophan concentrations and ratios are below normal in obese subjects and are not normalized by substantial weight reduction

    DEFF Research Database (Denmark)

    Breum, Leif; Rasmussen, Michael H; Hilsted, Jannik

    2003-01-01

    subjects. Blood samples were drawn frequently throughout the 24-h period. An insulin tolerance test was also used to determine whether weight loss altered the ability of insulin to modify plasma concentrations of tryptophan and of the other large neutral amino acids. RESULTS: Plasma tryptophan......BACKGROUND: Plasma tryptophan concentrations and the ratio of tryptophan to other large neutral amino acids (plasma tryptophan ratio) are reportedly low in obese subjects. The plasma tryptophan ratio predicts brain tryptophan uptake and serotonin production. If this ratio is low in obese subjects...... concentrations and ratios in obese subjects were low at all times; these effects persisted after weight reduction. Plasma concentrations of all the large neutral amino acids decreased during insulin infusion in all the groups. CONCLUSIONS: The low 24-h plasma tryptophan ratios in obese and formerly obese...

  18. Action potential broadening induced by lithium may cause a presynaptic enhancement of excitatory synaptic transmission in neonatal rat hippocampus.

    Science.gov (United States)

    Colino, A; García-Seoane, J J; Valentín, A

    1998-07-01

    Lithium enhances excitatory synaptic transmission in CA1 pyramidal cells, but the mechanisms remain unclear. The present study demonstrates that lithium enhances the N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-isoxazole propionic acid (AMPA) receptor-mediated components of the excitatory postsynaptic current (EPSC). Lithium decreased the magnitude of paired-pulse facilitation and presented an inverse correlation between the lithium-induced enhancement of synaptic transmission and initial paired-pulse facilitation, which is consistent with a presynaptic mode of action. The enhancement of synaptic strength is likely to act, at least in part, by increasing the amplitude of the presynaptic Ca2+ transient. One mechanism which could account for this change of the presynaptic Ca2+ transient is an increase in the duration of the action potential. We investigated action potential in hippocampal pyramidal neurons and found that lithium (0.5-6 mM) increased the half-amplitude duration and reduced the rate of repolarization, whereas the rate of depolarization remained similar. To find out whether the lithium synaptic effects might be explained by spike broadening, we investigated the field recording of the excitatory postsynaptic potential (EPSP) in hippocampal slices and found three lines of evidence. First, the prolongation of the presynaptic action potential with 4-aminopyridine and tetraethylammonium blocked or reduced the synaptic effects of lithium. Second, the lithium-induced synaptic enhancement was modulated when presynaptic Ca2+ influx was varied by changing the external Ca2+ concentration. Finally, both effects, the synaptic transmission increment and the action potential broadening, were independent of inositol depletion. These results suggest that lithium enhances synaptic transmission in the hippocampus via a presynaptic site of action: the mechanism underlying the potentiating effect may be attributable to an increased Ca2+ influx consequent

  19. The tryptophan hydroxylase activation inhibitor, AGN-2979, decreases regional 5-HT synthesis in the rat brain measured with alpha-[14C]methyl-L-tryptophan: an autoradiographic study.

    Science.gov (United States)

    Hasegawa, Shu; Kanemaru, Kazuya; Gittos, Maurice; Diksic, Mirko

    2005-10-15

    Many experimental conditions are stressful for animals. It is well known that stress induces tryptophan hydroxylase (TPH) activation, resulting in increased serotonin (5-HT) synthesis. In our experimental procedure to measure 5-HT synthesis using alpha-[(14)C]methyl-L-tryptophan (alpha-MTrp) autoradiographic method, the hind limbs of animals are restrained using a loose-fitted plaster cast such that the forelimbs of the animal remain free. The objective of the present investigation was to evaluate the changes, if any, in 5-HT synthesis, after injecting these restrained rats with the TPH activation inhibitor AGN-2979. The effect on regional 5-HT synthesis was studied using the alpha-MTrp autoradiographic method. The hypothesis was that the TPH activation inhibitor would reduce 5-HT synthesis, if TPH activation was induced by this restraint. The rats received injection of AGN-2979 (10 mg/kg, i.p.) or distilled water vehicle (1 mL/kg, i.p.) 1 h prior to tracer administration. The free- and total tryptophan concentrations were not significantly different between the treatment and control groups. The results demonstrate that 5-HT synthesis in AGN-2979 treated rats is significantly decreased (-12 to -35%) in both the raphe nuclei and their terminal areas when compared to the control rats. These findings suggest that restrained conditions, such as those used in our experimental protocol, induce TPH activation resulting in an increased 5-HT synthesis throughout the brain. The reduction in 5-HT synthesis in the AGN-2979 group is not related to a change in the plasma tryptophan. Because there was no activation in the pineal body, the structure having a different isoform of TPH, we can propose that it is only the brain TPH that becomes activated with this specific restraint.

  20. Composite electrodes for lithium batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Hackney, S. A.; Johnson, C. S.; Kahaian, A. J.; Kepler, K. D.; Shao-Horn, Y.; Thackeray, M. M.; Vaughey, J. T.

    1999-02-03

    The stability of composite positive and negative electrodes for rechargeable lithium batteries is discussed. Positive electrodes with spinel-type structures that are derived from orthorhombic-LiMnO{sub 2} and layered-MnO{sub 2} are significantly more stable than standard spinel Li[Mn{sub 2}]O{sub 4} electrodes when cycled electrochemically over both the 4-V and 3-V plateaus in lithium cells. Transmission electron microscope data of cycled electrodes have indicated that a composite domain structure accounts for this greater electrochemical stability. The performance of composite Cu{sub x}Sn materials as alternative negative electrodes to amorphous SnO{sub x} electrodes for lithium-ion batteries is discussed in terms of the importance of the concentration of the electrochemically inactive copper component in the electrode.

  1. Lithium clearance in chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

    1989-01-01

    1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption...... clearance data were independent of whether renal disease was of primarily glomerular or tubular origin and, further, were not influenced by long-term conventional antihypertensive treatment. 6. It is concluded that, even with a reduced kidney function, the data are compatible with the suggestion...... that lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

  2. Ingestion of branched-chain amino acids and tryptophan during sustained exercise in man: failure to affect performance

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; Raaymakers, J S; Saris, W H

    1995-01-01

    tryptophan ingestion caused a 7- to 20-fold increase. Exercise time to exhaustion was not different between treatments (122 +/- 3 min). 3. The data suggest that manipulation of tryptophan supply to the brain either has no additional effect upon serotoninergic activity during prolonged exhaustive exercise......1. An increased uptake of tryptophan in the brain may increase serotoninergic activity and recently has been suggested to be a cause of fatigue during prolonged exercise. The present study, therefore, investigates whether ingestion of tryptophan or the competing branched-chain amino acids (BCAAs......) affect performance. Ten endurance-trained male athletes were studied during cycle exercise at 70-75% maximal power output, while ingesting, ad random and double-blind, drinks that contained 6% sucrose (control) or 6% sucrose supplemented with (1) tryptophan (3 g l-1), (2) a low dose of BCAA (6 g l-1...

  3. Ingestion of branched-chain amino acids and tryptophan during sustained exercise in man: failure to affect performance

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; Raaymakers, J S; Saris, W H

    1995-01-01

    1. An increased uptake of tryptophan in the brain may increase serotoninergic activity and recently has been suggested to be a cause of fatigue during prolonged exercise. The present study, therefore, investigates whether ingestion of tryptophan or the competing branched-chain amino acids (BCAAs...... tryptophan ingestion caused a 7- to 20-fold increase. Exercise time to exhaustion was not different between treatments (122 +/- 3 min). 3. The data suggest that manipulation of tryptophan supply to the brain either has no additional effect upon serotoninergic activity during prolonged exhaustive exercise......) or (3) a high dose of BCAA (18 g l-1). 2. These treatments greatly increased the plasma concentration of the respective amino acids. Using the kinetic parameters of transport of human brain capillaries, BCAA supplements were estimated to reduce brain tryptophan uptake at exhaustion by 8-12%, while...

  4. The Role of the Microbial Metabolites Including Tryptophan Catabolites and Short Chain Fatty Acids in the Pathophysiology of Immune-Inflammatory and Neuroimmune Disease.

    Science.gov (United States)

    Morris, Gerwyn; Berk, Michael; Carvalho, Andre; Caso, Javier R; Sanz, Yolanda; Walder, Ken; Maes, Michael

    2016-06-27

    There is a growing awareness that gut commensal metabolites play a major role in host physiology and indeed the pathophysiology of several illnesses. The composition of the microbiota largely determines the levels of tryptophan in the systemic circulation and hence, indirectly, the levels of serotonin in the brain. Some microbiota synthesize neurotransmitters directly, e.g., gamma-amino butyric acid, while modulating the synthesis of neurotransmitters, such as dopamine and norepinephrine, and brain-derived neurotropic factor (BDNF). The composition of the microbiota determines the levels and nature of tryptophan catabolites (TRYCATs) which in turn has profound effects on aryl hydrocarbon receptors, thereby influencing epithelial barrier integrity and the presence of an inflammatory or tolerogenic environment in the intestine and beyond. The composition of the microbiota also determines the levels and ratios of short chain fatty acids (SCFAs) such as butyrate and propionate. Butyrate is a key energy source for colonocytes. Dysbiosis leading to reduced levels of SCFAs, notably butyrate, therefore may have adverse effects on epithelial barrier integrity, energy homeostasis, and the T helper 17/regulatory/T cell balance. Moreover, dysbiosis leading to reduced butyrate levels may increase bacterial translocation into the systemic circulation. As examples, we describe the role of microbial metabolites in the pathophysiology of diabetes type 2 and autism.

  5. Lithium synthesis in microquasar accretion.

    Science.gov (United States)

    Iocco, Fabio; Pato, Miguel

    2012-07-13

    We study the synthesis of lithium isotopes in the hot tori formed around stellar mass black holes by accretion of the companion star. We find that sizable amounts of both stable isotopes 6Li and 7Li can be produced, the exact figures varying with the characteristics of the torus and reaching as much as 10(-2) M⊙ for each isotope. This mass output is enough to contaminate the entire Galaxy at a level comparable with the original, pregalactic amount of lithium and to overcome other sources such as cosmic-ray spallation or stellar nucleosynthesis.

  6. Optimizing lithium dosing in hemodialysis

    DEFF Research Database (Denmark)

    Bjarnason, N H; Munkner, R; Kampmann, J P;

    2006-01-01

    We studied a 62-year-old female hemodialysis patient during initiation and maintenance of lithium carbonate therapy. Three different methods were applied to estimate the regimen: a scenario based on volume of distribution (V(d)), a scenario based on glomerular filtration rate (GFR), and a scenario...... in this patient with no residual kidney function. We did not observe adverse effects related to this regimen, which was monitored from 18 days to 8 months of therapy, and the patient experienced relief from her severe depressive disorder. In conclusion, dialysis patients may be treated with lithium administrated...

  7. Lithium nephropathy: unique sonographic findings.

    Science.gov (United States)

    Di Salvo, Donald N; Park, Joseph; Laing, Faye C

    2012-04-01

    This case series describes a unique sonographic appearance consisting of numerous microcysts and punctate echogenic foci seen on renal sonograms of 10 adult patients receiving chronic lithium therapy. Clinically, chronic renal insufficiency was present in 6 and nephrogenic diabetes insipidus in 2. Sonography showed numerous microcysts and punctate echogenic foci. Computed tomography in 5 patients confirmed microcysts and microcalcifications, which were fewer in number than on sonography. Magnetic resonance imaging in 2 patients confirmed microcysts in each case. Renal biopsy in 1 patient showed chronic interstitial nephritis, microcysts, and tubular dilatation. The diagnosis of lithium nephropathy should be considered when sonography shows these findings.

  8. Predictors of excellent response to lithium

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Hellmund, Gunnar; Andersen, Per Kragh

    2011-01-01

    The aim of this study was to identify sociodemographic and clinical predictors of excellent response, that is, 'cure' of future affective episodes, to lithium in monotherapy. We used nationwide registers to identify all patients with a diagnosis of bipolar disorder in psychiatric hospital settings...... who were prescribed lithium from 1995 to 2006 in Denmark (N=3762). Excellent lithium responders were defined as patients who after a stabilization lithium start-up period of 6 months, continued lithium in monotherapy without getting hospitalized. The rate of excellent response to lithium...... in monotherapy was 8.9% [95% confidence interval (CI): 7.9-9.9] at 5-year follow-up and 5.4% (95% CI: 4.4-6.3) at 10-year follow-up. The rate of nonresponse to lithium monotherapy was significantly increased for female patients [hazards ratio (HR)=1.12, 95% CI: 1.04-1.21) and for patients with a depressive index...

  9. Surface protected lithium-metal-oxide electrodes

    Science.gov (United States)

    Thackeray, Michael M.; Kang, Sun-Ho

    2016-04-05

    A lithium-metal-oxide positive electrode having a layered or spinel structure for a non-aqueous lithium electrochemical cell and battery is disclosed comprising electrode particles that are protected at the surface from undesirable effects, such as electrolyte oxidation, oxygen loss or dissolution by one or more lithium-metal-polyanionic compounds, such as a lithium-metal-phosphate or a lithium-metal-silicate material that can act as a solid electrolyte at or above the operating potential of the lithium-metal-oxide electrode. The surface protection significantly enhances the surface stability, rate capability and cycling stability of the lithium-metal-oxide electrodes, particularly when charged to high potentials.

  10. Solid solution lithium alloy cermet anodes

    Science.gov (United States)

    Richardson, Thomas J.

    2013-07-09

    A metal-ceramic composite ("cermet") has been produced by a chemical reaction between a lithium compound and another metal. The cermet has advantageous physical properties, high surface area relative to lithium metal or its alloys, and is easily formed into a desired shape. An example is the formation of a lithium-magnesium nitride cermet by reaction of lithium nitride with magnesium. The reaction results in magnesium nitride grains coated with a layer of lithium. The nitride is inert when used in a battery. It supports the metal in a high surface area form, while stabilizing the electrode with respect to dendrite formation. By using an excess of magnesium metal in the reaction process, a cermet of magnesium nitride is produced, coated with a lithium-magnesium alloy of any desired composition. This alloy inhibits dendrite formation by causing lithium deposited on its surface to diffuse under a chemical potential into the bulk of the alloy.

  11. Digestible tryptophan:digestible lysine ratio in diets for laying hens from 24 to 40 weeks of age

    Directory of Open Access Journals (Sweden)

    Arele Arlindo Calderano

    2012-10-01

    Full Text Available The objective of this study was to determine the ideal digestible tryptophan:digestible lysine ratio in diets for laying hens from 24 to 40 weeks of age. Two hundred and forty Hy-Line W-36 laying hens at 24 weeks of age were distributed in a completely randomized design, with five treatments, eight replicates and six birds per experimental unit. The digestible tryptophan levels in the experimental diets were 1.57; 1.68; 1.79; 1.90 and 2.01 g/kg, providing ratios of digestible tryptophan:digestible lysine of 0.215; 0.230; 0.245; 0.260 and 0.275. The increase in the levels of digestible tryptophan in the diet linearly improved the feed intake, digestible tryptophan intake, digestible lysine intake, egg production, egg mass, feed conversion per egg mass and utilization efficiency of digestible lysine for eggs mass. There were quadratic effects from the digestible tryptophan levels on egg weight. For the efficiency of utilization of digestible lysine for egg mass, there was better adjustment of the data to the LRP model. The level of digestible tryptophan in the diet from which the plateau occurred was 0.184%. This level corresponded to the intake of 142 mg/bird/day of digestible tryptophan and digestible tryptophan:digestible lysine ratio of 0.252. The ideal digestible tryptophan:digestible lysine ratio recommended in diets for laying hens from 24 to 40 weeks of age is 0.252 (25.2%.

  12. 49 CFR 173.185 - Lithium cells and batteries.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Lithium cells and batteries. 173.185 Section 173... Class 7 § 173.185 Lithium cells and batteries. (a) Cells and batteries. A lithium cell or battery, including a lithium polymer cell or battery and a lithium-ion cell or battery, must conform to all of...

  13. Review and Outlook of China’s Lithium Market

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>In 2011 China’s lithium carbonate output was about 30000 tonnes. In 2012, China’s lithium carbonate output (including battery grade lithium carbonate) was 35000 tonnes, up by 17% on Y-o-Y basis. (1) Capacity of Ganfeng Lithium expanded considerably The company enjoys obvious technological advantages, its organic lithium deep processing

  14. Nutritional Stress Induced by Tryptophan-Degrading Enzymes Results in ATF4-Dependent Reprogramming of the Amino Acid Transporter Profile in Tumor Cells

    DEFF Research Database (Denmark)

    Timosenko, Elina; Ghadbane, Hemza; Silk, Jonathan D

    2016-01-01

    Tryptophan degradation is an immune escape strategy shared by many tumors. However, cancer cells' compensatory mechanisms remain unclear. We demonstrate here that a shortage of tryptophan caused by expression of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) resulted in AT...

  15. Lithium to back photovoltaic; Le lithium au service du photovoltaique

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2006-01-15

    Lithium-ion batteries have valuable assets to be an alternative to lead batteries for the storage of solar energy: they age 5 times less quickly, they do not require maintenance and they show a good charge-discharge cycling with no sensitivity to cycle interruptions. (A.C.)

  16. Containment system and thermal conduction in lithium electric batteries energy modules 2 kWh with polymeric electrolytes; Sviluppo del sistema di contenimento e del condizionamento termico di moduli da 2 kWh di batterie al litio ad elettrolita polimerico

    Energy Technology Data Exchange (ETDEWEB)

    Ciancia, A.; Alessandrini, F. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Energia Divisione Tecnologie Energetiche Avanzate

    1997-06-01

    In this work are presented some technical specifications regarding lithium electric batteries with polymeric electrolytes, in particular the design of electrodes container efficient and reliable and thermal management system oriented to safety, performances and battery life.

  17. Central fatigue and nycthemeral change of serum tryptophan and serotonin in the athletic horse

    Directory of Open Access Journals (Sweden)

    Percipalle Maurizio

    2005-04-01

    Full Text Available Abstract Background The serotonergic system is associated with numerous brain functions, including the resetting of the mammalian circadian clock. The synthesis and metabolism of 5-HT in the brain increases in response to exercise and is correlated with high levels of blood-borne tryptophan (TRP. The present investigation was aimed at testing the existence of a daily rhythm of TRP and 5-HT in the blood of athletic horses. Methods Blood samples from 5 Thoroughbred mares were collected at 4-hour intervals for 48 hours (starting at 08:00 hours on day 1 and finishing at 4:00 on day 2 via an intravenous cannula inserted into the jugular vein. Tryptophan and serotonin concentrations were assessed by HPLC. Data analysis was conducted by one-way repeated measures analysis of variance (ANOVA and by the single cosinor method. Results ANOVA showed a highly significant influence of time both on tryptophan and on serotonin, in all horses, on either day, with p values Conclusion The results showed that serotonin and tryptophan blood levels undergo nycthemeral variation with typical evening acrophases. These results enhance the understanding of the athlete horse's chronoperformance and facilitate the establishment of training programs that take into account the nycthemeral pattern of aminoacids deeply involved in the onset of central fatigue.

  18. Cross-linking of lens crystallin proteins induced by tryptophan metabolites and metal ions

    DEFF Research Database (Denmark)

    Tweeddale, Helen J; Hawkins, Clare Louise; Janmie, Joane F

    2016-01-01

    Long-wavelength solar UV radiation is implicated in photodamage to the human eye. The human lens contains multiple tryptophan-derived compounds that have significant absorbance bands in the UVA region (λ 315-400 nm) that act as efficient physical filters for these wavelengths. The concentrations...

  19. Diurnal variation in total plasma tryptophan in controls and in depression.

    Science.gov (United States)

    Candito, M; Souêtre, E; Iordache, A; Pringuey, D; Ardisson, J L; Chambon, P; Darcourt, G

    1990-01-01

    Circadian rhythms of total tryptophan were investigated by assays of hourly blood samples over 25 h. The study population consisted of four endogenously depressed patients investigated in the absence of any treatment and six healthy controls. The abnormalities detected by statistical analyses in untreated depression consisted mainly of amplitude reduction; the phase positions of the depressed patients were similar to those of the controls.

  20. REPLACEMENT OF TRYPTOPHAN RESIDUES IN HALOALKANE DEHALOGENASE REDUCES HALIDE BINDING AND CATALYTIC ACTIVITY

    NARCIS (Netherlands)

    KENNES, C; PRIES, F; KROOSHOF, GH; BOKMA, E; Kingma, Jacob; JANSSEN, DB

    1995-01-01

    Haloalkane dehalogenase catalyzes the hydrolytic cleavage of carbon-halogen bonds in short-chain haloalkanes. Two tryptophan residues of the enzyme (Trp125 and Trp175) form a halide-binding site in the active-site cavity, and were proposed to play a role in catalysis. The function of these residues

  1. A Relay Pathway between Arginine and Tryptophan Metabolism Confers Immunosuppressive Properties on Dendritic Cells

    NARCIS (Netherlands)

    G. Mondanelli (Giada); R. Bianchi (Roberta); M.T. Pallotta (Maria Teresa); C. Orabona (Ciriana); E. Albini (Elisa); A. Iacono (Alberta); M.L. Belladonna (Maria Laura); C. Vacca (Carmine); F. Fallarino (Francesca); A. Macchiarulo (Antonio); S. Ugel (Stefano); V. Bronte (Vincenzo); F. Gevi (Federica); L. Zolla (Lello); A.P. Verhaar (Auke); M.P. Peppelenbosch (Maikel); E.M.C. Mazza (Emilia Maria Cristina); S. Bicciato (Silvio); Y. Laouar (Yasmina); L. Santambrogio (Laura); P. Puccetti (Paolo); C. Volpi (Claudia); U. Grohmann (Ursula)

    2016-01-01

    textabstractArginase 1 (Arg1) and indoleamine 2,3-dioxygenase 1 (IDO1) are immunoregulatory enzymes catalyzing the degradation of l-arginine and l-tryptophan, respectively, resulting in local amino acid deprivation. In addition, unlike Arg1, IDO1 is also endowed with non-enzymatic signaling activity

  2. Serum Stabilities of Short Tryptophan-and Arginine-Rich Antimicrobial Peptide Analogs

    NARCIS (Netherlands)

    Nguyen, L.T.; Chau, J.K.; Perry, N.A.; de Boer, L.; Zaat, S.A.J.; Vogel, H.J.

    2010-01-01

    Background: Several short antimicrobial peptides that are rich in tryptophan and arginine residues were designed with a series of simple modifications such as end capping and cyclization. The two sets of hexapeptides are based on the Trp- and Arg-rich primary sequences from the "antimicrobial centre

  3. Molecular docking of bacosides with tryptophan hydroxylase: a model to understand the bacosides mechanism.

    Science.gov (United States)

    Rajathei, David Mary; Preethi, Jayakumar; Singh, Hemant K; Rajan, Koilmani Emmanuvel

    2014-08-01

    Tryptophan hydroxylase (TPH) catalyses l-tryptophan into 5-hydroxy-l-tryptophan, which is the first and rate-limiting step of serotonin (5-HT) biosynthesis. Earlier, we found that TPH2 up-regulated in the hippocampus of postnatal rats after the oral treatment of Bacopa monniera leaf extract containing the active compound bacosides. However, the knowledge about the interactions between bacosides with TPH is limited. In this study, we take advantage of in silico approach to understand the interaction of bacoside-TPH complex using three different docking algorithms such as HexDock, PatchDock and AutoDock. All these three algorithms showed that bacoside A and A3 well fit into the cavity consists of active sites. Further, our analysis revealed that major active compounds bacoside A3 and A interact with different residues of TPH through hydrogen bond. Interestingly, Tyr235, Thr265 and Glu317 are the key residues among them, but none of them are either at tryptophan or BH4 binding region. However, its note worthy to mention that Tyr 235 is a catalytic sensitive residue, Thr265 is present in the flexible loop region and Glu317 is known to interacts with Fe. Interactions with these residues may critically regulate TPH function and thus serotonin synthesis. Our study suggested that the interaction of bacosides (A3/A) with TPH might up-regulate its activity to elevate the biosynthesis of 5-HT, thereby enhances learning and memory formation.

  4. Effect of a B-vitamin on tryptophan metabolism in South African Bantu with pellagra

    Energy Technology Data Exchange (ETDEWEB)

    Hankes, L.V.; Jansen, C.R.; DeBruin, E.P.; Schmaeler, M.

    1983-01-01

    The metabolism of kynurenine, a metabolite in the tryptophan-niacin pathway, before and after vitamin B6 therapy was studied in pellagra patients. The patients given vitamin B6 showed a higher metabolism of L-kynurenine-keto-/sup 14/C than the patients without vitamin B6. (ACR)

  5. Effect of diet on plasma tryptophan and serotonin in trained mares and geldings

    NARCIS (Netherlands)

    Alberghina, D.; Giannetto, C.; Visser, E.K.; Ellis, A.D.

    2010-01-01

    Concentrations of tryptophan (TRP) and serotonin (5-HT) in plasma were measured in 36 moderately trained Dutch warmblood horses after eight weeks on a high fibre (n=18) or high starch (n=18) diet. Samples were taken three hours after feeding, when the horse was at rest, either at 11.00 or 14.00 hour

  6. Lactococcus lactis as expression host for the biosynthetic incorporation of tryptophan analogues into recombinant proteins

    NARCIS (Netherlands)

    El Khattabi, Mohamed; van Roosmalen, Maarten L.; Jager, Dennis; Metselaar, Heidi; Permentier, Hjalmar; Leenhouts, Kees; Broos, Jaap

    2008-01-01

    Incorporation of Trp (tryptophan) analogues into a protein may facilitate its structural analysis by spectroscopic techniques. Development of a biological system for the biosynthetic incorporation of such analogues into proteins is of considerable importance. The Gram-negative Escherichia coli is th

  7. Converging evidence for central 5-HT effects in acute tryptophan depletion

    DEFF Research Database (Denmark)

    Crockett, Molly; Clark, Luke; Roiser, Jonathan

    2012-01-01

    Acute tryptophan depletion (ATD), a dietary technique for manipulating brain serotonin (5-HT) function, has advanced our understanding of 5-HT mechanisms in the etiology and treatment of depression and other affective disorders.1 A recent review article in Molecular Psychiatry questioned the vali...

  8. Synthesis of 2-substituted tryptophans via a C3- to C2-alkyl migration

    Directory of Open Access Journals (Sweden)

    Michele Mari

    2014-08-01

    Full Text Available The reaction of 3-substituted indoles with dehydroalanine (Dha derivatives under Lewis acid-mediated conditions has been investigated. The formation of 2-substituted tryptophans is proposed to occur through a selective alkylative dearomatization–cyclization followed by C3- to C2-alkyl migration and rearomatization.

  9. Recognizing emotions in faces : effects of acute tryptophan depletion and bright light

    NARCIS (Netherlands)

    aan het Rot, Marije; Coupland, Nicholas; Boivin, Diane B.; Benkelfat, Chawki; Young, Simon N.

    2010-01-01

    In healthy never-depressed individuals, acute tryptophan depletion (ATD) may selectively decrease the accurate recognition of fearful facial expressions. Here we investigated the perception of facial emotions after ATD in more detail. We also investigated whether bright light, which can reverse ATD'

  10. Dietary tryptophan and threonine supply to 28 days old weaned piglets

    DEFF Research Database (Denmark)

    Fernández, José Adalberto; Strathe, Anders Bjerring

    2009-01-01

    The effects of dietary levels of tryptophan (TRP) and threonine (THR) on appetite, growth performance and faecal score were assessed in an experiment with 360 weaned piglets. Littermate male castrates and females (1:1), weaned at 28 days of age, were given free access to feed during 28 days. Six...

  11. The tryptophan kynurenine pathway, neopterin and IL-6 during vulvectomy and abdominal hysterectomy.

    Science.gov (United States)

    Hol, Jaap Willem; Stolker, Robert J; Klimek, Markus; Stronks, Dirk L; Fekkes, Durk

    2014-12-20

    Surgery has wide ranging immunomodulatory properties of which the mechanism is poorly understood. In order to investigate how different types of surgery influence inflammation, we designed a longitudinal observational study investigating two inflammatory profiles of two separate patient groups undergoing gynaecological operations of differing severity. In addition to measuring the well known inflammatory markers neopterin and IL-6, we also determined the kynurenine/tryptophan ratio. This study was a prospective, single center, two-armed observational study involving 28 female patients. Plasma levels of tryptophan, kynurenine, neopterin and IL-6 were determined from samples taken at: 24 hrs pre-operative, prior to induction, ten minutes before the operation was expected to end, and at 24 and 96 hours post operative in patients undergoing abdominal hysterectomy and vulvectomy. There were 15 and 13 patients included in the vulvectomy and abdominal hysterectomy groups, respectively. In this study we show that anesthesia and surgery significantly increases the enzyme activity of indoleamine 2, 3 dioxygenase (IDO) as measured by the kynurenine/tryptophan ratio (P=0.003), while maintaining stable neopterin levels. However, abdominal hysterectomy causes a considerable IL-6 increase (P<0.001). Surgery and associated anesthesia cause a significant tryptophan level decrease while significantly increasing IDO activity. Both types of surgery produce nearly identical neopterin time curve relationships, with no significant change occurring in either group. However, even though neopterin is unaffected by the severity of surgery, IL-6 responded to surgical invasiveness by revealing a significant increase during abdominal hysterectomy.

  12. Tryptophan Content of the Serum Albumin of Normal and of Cadmium-Poisoned Monkeys

    Science.gov (United States)

    Kench, J. E.; Sutherland, Elizabeth M.

    1967-01-01

    In order to characterize further the minialbumins (molecular weight 5,000 to 20,000) found in cadmium-poisoned men and animals, the tryptophan content of albumins found in the serum and urine of cadmium-poisoned monkeys was measured by two methods and compared with that of serum albumin (molecular weight 66,000) of normal animals. Normal serum albumin of the monkey was found to contain 2 residues of trytophan per molecule of the protein, whereas all albumins in the poisoned monkeys, whether of normal size or low-molecular weight, contained less tryptophan, this amino acid being absent entirely in the minialbumins of both serum and urine. Serum albumin of the usual molecular weight (66,000) in the cadmium-poisoned monkeys contained approximately 30% less tryptophan than its normal counterpart in untreated animals. Taken in conjunction with previous observations on the behaviour of minialbumins, which aggregate readily in low-salt media including isotonic saline, it is concluded that approximately 30% of the circulating serum albumin in the poisoned monkeys arose by aggregation of minialbumin molecules. On the basis of the close similarity in amino acid composition, in nearly all other respects, between the various albumins, it is suggested that minialbumin comprises a mixture of peptides derived by fission of the normal albumin molecule along its whole chain length, and that subsequently a peptide containing both tryptophan residues is either deleted metabolically or excluded in the preparation procedures. PMID:4965263

  13. Biotransformation of tryptophan by liquid medium culture of Psilocybe coprophila (Basidiomycetes).

    Science.gov (United States)

    Alarcón, Julio; Foncea, Leyla; Aguila, Sergio; Alderete, Joel B

    2006-01-01

    Chemical reactions performed by fungi have been used as a modern tool in chemistry. In this work, we show the tryptophan biotransformation with Psilocybe coprophila on liquid culture medium. The results prove once more the versatility of fungi in performing a wide range of industrially attractive chemical reactions.

  14. Tetrahydro-beta-carboline-3-carboxylic acids and contaminants of L-tryptophan.

    Science.gov (United States)

    Adachi, J; Asano, M; Ueno, Y

    2000-06-09

    Methods for the separation, identification, and quantitative assay of contaminants of L-tryptophan implicated in eosinophilia-myalgia syndrome (EMS) are described. Propylsulfonic acid (PRS), benzenesulfonic acid (SCX), and octyl-derivatized silica (C8) bonded-phase cartridges were used for the separation; LC-MS and GC-MS for identification; and HPLC-UV-fluorescence detection for quantitative analyses of norharman, harman, tetrahydro-beta-carboline-3-carboxylic acid (TCCA), 1-methyltetrahydro-beta-carboline-3-carboxylic acid (MTCA), 1,1'-ethylidenbis(tryptophan) (EBT), and 3-(phenylamino)alanine (PAA). The tissue distribution, excretion, and metabolism of these contaminants of L-tryptophan associated with EMS after acute and chronic dosage regimens are described. Considerable amounts of EBT were observed in the large intestine of rats administered EBT, showing a transfer without decomposition in gastric fluid. In addition, MTCA was detected in the blood and urine as well as the organs of rats treated with EBT, suggesting MTCA as a major metabolite of EBT. PAA accumulated markedly in the brain, among the organs of rats, after both acute and chronic administration of PAA, while MTCA accumulated in the kidneys of rats after chronic dosage of MTCA. Ethanol and/or acetaldehyde-induced formation of MTCA, as well as tryptophan-induced formation of TCCA, occurred endogenously in man and animals.

  15. Experimental Evidence and In Silico Identification of Tryptophan Decarboxylase in Citrus Genus

    Directory of Open Access Journals (Sweden)

    Luigi De Masi

    2017-02-01

    Full Text Available Plant tryptophan decarboxylase (TDC converts tryptophan into tryptamine, precursor of indolealkylamine alkaloids. The recent finding of tryptamine metabolites in Citrus plants leads to hypothesize the existence of TDC activity in this genus. Here, we report for the first time that, in Citrus x limon seedlings, deuterium labeled tryptophan is decarboxylated into tryptamine, from which successively deuterated N,N,N-trimethyltryptamine is formed. These results give an evidence of the occurrence of the TDC activity and the successive methylation pathway of the tryptamine produced from the tryptophan decarboxylation. In addition, with the aim to identify the genetic basis for the presence of TDC, we carried out a sequence similarity search for TDC in the Citrus genomes using as a probe the TDC sequence reported for the plant Catharanthus roseus. We analyzed the genomes of both Citrus clementina and Citrus sinensis, available in public database, and identified putative protein sequences of aromatic l-amino acid decarboxylase. Similarly, 42 aromatic l-amino acid decarboxylase sequences from 23 plant species were extracted from public databases. Potential sequence signatures for functional TDC were then identified. With this research, we propose for the first time a putative protein sequence for TDC in the genus Citrus.

  16. Distinct Tryptophan Catabolism and Th17/Treg Balance in HIV Progressors and Elite Controllers

    NARCIS (Netherlands)

    Jenabian, Mohammad-Ali; Patel, Mital; Kema, Ido; Kanagaratham, Cynthia; Radzioch, Danuta; Thebault, Pamela; Lapointe, Rejean; Tremblay, Cecile; Gilmore, Norbert; Ancuta, Petronela; Routy, Jean-Pierre

    2013-01-01

    Tryptophan (Trp) catabolism into immunosuppressive kynurenine (Kyn) by indoleamine 2,3-dioxygenase (IDO) was previously linked to Th17/Treg differentiation and immune activation. Here we examined Trp catabolism and its impact on Th17/Treg balance in uninfected healthy subjects (HS) and a large cohor

  17. Problem-Solving Test: Attenuation--A Mechanism to Regulate Bacterial Tryptophan Biosynthesis

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    Terms to be familiar with before you start to solve the test: tryptophan, transcription unit, operon, "trp" repressor, corepressor, operator, promoter, palindrome, initiation, elongation, and termination of transcription, open reading frame, coupled transcription/translation, chromosome-polysome complex. (Contains 2 figures and 1 footnote.)

  18. PYROLYTIC PRODUCTS FROM TRYPTOPHAN AND GLUTAMIC-ACID ARE POSITIVE IN THE MAMMALIAN SPOT-TEST

    DEFF Research Database (Denmark)

    Jensen, Niels Juul

    1983-01-01

    Pyrolysates of tryptophan (Trp-P-2) and glutamic acid (Glu-P-1) are known mutagens in in vitro short term mutagenicity tests, and have also shown carcinogenic effects in long term animal studies. The present study demonstrates that they also produce mutations in somatic cells. This result...

  19. A novel photocatalytic conversion of Tryptophan to Kynurenine using black light as a light source

    NARCIS (Netherlands)

    Hamdy Mohamed Saad, M.S.; Scott, E.L.; Carr, R.H.; Sanders, J.P.M.

    2012-01-01

    The photocatalytic conversion of an aqueous solution of l-tryptophan (Trp) to kynurenine (KN) was investigated under the illumination of different light sources. Results show that Trp converted to KN with a selectivity of 64% under the illumination of a medium pressure (MP) Hg lamp. KN selectivity w

  20. Internal Energies of Ion-Sputtered Neutral Tryptophan and Thymine Molecules Determined by Vacuum Ultraviolet Photoionization

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jia; Takahashi, Lynelle; Wilson, Kevin R.; Leone, Stephen R.; Ahmed, Musahid

    2010-03-11

    Vacuum ultraviolet photoionization coupled to secondary neutral mass spectrometry (VUV-SNMS) of deposited tryptophan and thymine films are performed at the Chemical Dynamics Beamline. The resulting mass spectra show that while the intensity of the VUV-SNMS signal is lower than the corresponding secondary ion mass spectroscopy (SIMS) signal, the mass spectra are significantly simplified in VUV-SNMS. A detailed examination of tryptophan and thymine neutral molecules sputtered by 25 keV Bi3 + indicates that the ion-sputtered parent molecules have ~;;2.5 eV of internal energy. While this internal energy shifts the appearance energy of the photofragment ions for both tryptophan and thymine, it does not change the characteristic photoionizaton efficiency (PIE) curves of thymine versus photon energy. Further analysis of the mass spectral signals indicate that approximately 80 neutral thymine molecules and 400 tryptophan molecules are sputtered per incident Bi3 + ion. The simplified mass spectra and significant characteristic ion contributions to the VUV-SNMS spectra indicate the potential power of the technique for organic molecule surface analysis.

  1. Stabilization of Tryptophan Hydroxylase 2 by L-Phenylalanine Induced Dimerization

    DEFF Research Database (Denmark)

    Tidemand, Kasper Damgaard; Christensen, Hans Erik Mølager; Hoeck, Niclas;

    2016-01-01

    Tryptophan hydroxylase 2 (TPH2) catalyses the initial and rate-limiting step in the biosynthesis of serotonin, which is associated with a variety of disorders such as depression, obsessive compulsive disorder, and schizophrenia. Full length TPH2 is poorly characterized due to low purification qua...

  2. Quenching of Tryptophan Fluorescence in Unfolded Cytochrome "c": A Biophysics Experiment for Physical Chemistry Students

    Science.gov (United States)

    Schlamadinger, Diana E.; Kats, Dina I.; Kim, Judy E.

    2010-01-01

    Laboratory experiments that focus on protein folding provide excellent opportunities for undergraduate students to learn important topics in the expanding interdisciplinary field of biophysics. Here, we describe the use of Stern-Volmer plots to determine the extent of solvent accessibility of the single tryptophan residue (trp-59) in unfolded and…

  3. Study of Interaction Between Tryptophan, Tyrosine, and Phenylalanine Separately with Silver Nanoparticles by Fluorescence Quenching Method

    Science.gov (United States)

    Roy, S.; Das, T. K.

    2015-09-01

    Using the spectroscopic method, the individual interaction of the three biochemically important amino acids, which are constituents of protein, namely, tryptophan, tyrosine, and phenylalanine with biologically synthesized silver nanoparticles has been investigated. The obtained UV-Vis spectra show the formation of ground-state complexes between tryptophan, tyrosine, and phenylalanine with silver nanoparticles. Silver nanoparticles possess the ability to quench the intrinsic fluorescence of the aforesaid amino acids by a dynamic quenching process. The binding constant, number of binding sites, and corresponding thermodynamic parameters (Δ H, Δ S, and Δ G) based on the interaction system were calculated for 293, 303, and 313 K. In the case of tryptophan and phenylalanine, with increase in temperature, the binding constant K was found to decrease; conversely, it was found to increase with increase in temperature in the case of tyrosine. The thermodynamic results revealed that the binding process was spontaneous; hydrogen bonding and van der Waals interaction were the predominant forces responsible for the complex stabilization in the case of tryptophan and phenylalanine, respectively, whereas in the case of tyrosine, hydrophobic interaction was the sole force conferring stability. Moreover, the Förster non-radiation energy transfer theory has been applied to calculate the average binding distance among the above amino acids and silver nanoparticles. The results show a binding distance of <7 nm, which ensures that energy transfer does occur between the said amino acids and silver nanoparticles.

  4. Melatonin biosynthesis in plants: multiple pathways catalyze tryptophan to melatonin in the cytoplasm or chloroplasts.

    Science.gov (United States)

    Back, Kyoungwhan; Tan, Dun-Xian; Reiter, Russel J

    2016-11-01

    Melatonin is an animal hormone as well as a signaling molecule in plants. It was first identified in plants in 1995, and almost all enzymes responsible for melatonin biosynthesis had already been characterized in these species. Melatonin biosynthesis from tryptophan requires four-step reactions. However, six genes, that is, TDC, TPH, T5H, SNAT, ASMT, and COMT, have been implicated in the synthesis of melatonin in plants, suggesting the presence of multiple pathways. Two major pathways have been proposed based on the enzyme kinetics: One is the tryptophan/tryptamine/serotonin/N-acetylserotonin/melatonin pathway, which may occur under normal growth conditions; the other is the tryptophan/tryptamine/serotonin/5-methoxytryptamine/melatonin pathway, which may occur when plants produce large amounts of serotonin, for example, upon senescence. The melatonin biosynthetic capacity associated with conversion of tryptophan to serotonin is much higher than that associated with conversion of serotonin to melatonin, which yields a low level of melatonin synthesis in plants. Many melatonin intermediates are produced in various subcellular compartments, such as the cytoplasm, endoplasmic reticulum, and chloroplasts, which either facilitates or impedes the subsequent enzymatic steps. Depending on the pathways, the final subcellular sites of melatonin synthesis vary at either the cytoplasm or chloroplasts, which may differentially affect the mode of action of melatonin in plants. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Reprint of 'pH tuning of Nafion for selective detection of tryptophan'

    Energy Technology Data Exchange (ETDEWEB)

    Frith, K.-A. [Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, 6140 (South Africa); Limson, J.L., E-mail: j.limson@ru.ac.z [Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, 6140 (South Africa)

    2010-05-30

    Selective and sensitive detection of the amino acid tryptophan is of importance in food processing, pharmaceutical formulations and in biological fluids. Electrochemical methods of detection of tryptophan are hampered by sluggish electron transfer kinetics and in complex matrices through overlapping peaks from interferents. This study examines the potential of the cation exchange membrane Nafion to enhance selectivity and sensitivity of this analyte through a seldom explored feature of this membrane: pH manipulation. A detailed examination of the effect of pH on the selectivity afforded by Nafion as a function of the analyte charge is presented. Selective detection of tryptophan and significant increases in sensitivity of its detection was observed in the presence of melatonin, dopamine and other interferents present in a pharmaceutical formulation through manipulation of the pH of the solution. At pH 3.0 at a Nafion-modified electrode, changes in the protonation of melatonin and tryptophan lowered the anodic potential of the analytes in a non-uniform manner increasing the peak resolution and permitting analyses with detection limits of 1.6 +- 0.1 nM and 1.6 +- 0.2 nM, respectively.

  6. pH tuning of Nafion for selective detection of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Frith, K.-A. [Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, 6140 (South Africa); Limson, J.L. [Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, 6140 (South Africa)], E-mail: j.limson@ru.ac.za

    2009-05-01

    Selective and sensitive detection of the amino acid tryptophan is of importance in food processing, pharmaceutical formulations and in biological fluids. Electrochemical methods of detection of tryptophan are hampered by sluggish electron transfer kinetics and in complex matrices through overlapping peaks from interferents. This study examines the potential of the cation exchange membrane Nafion to enhance selectivity and sensitivity of this analyte through a seldom explored feature of this membrane: pH manipulation. A detailed examination of the effect of pH on the selectivity afforded by Nafion as a function of the analyte charge is presented. Selective detection of tryptophan and significant increases in sensitivity of its detection was observed in the presence of melatonin, dopamine and other interferents present in a pharmaceutical formulation through manipulation of the pH of the solution. At pH 3.0 at a Nafion-modified electrode, changes in the protonation of melatonin and tryptophan lowered the anodic potential of the analytes in a non-uniform manner increasing the peak resolution and permitting analyses with detection limits of 1.6 {+-} 0.1 nM and 1.6 {+-} 0.2 nM, respectively.

  7. Quantum chemical calculations of tryptophan → heme electron and excitation energy transfer rates in myoglobin.

    Science.gov (United States)

    Suess, Christian J; Hirst, Jonathan D; Besley, Nicholas A

    2017-04-01

    The development of optical multidimensional spectroscopic techniques has opened up new possibilities for the study of biological processes. Recently, ultrafast two-dimensional ultraviolet spectroscopy experiments have determined the rates of tryptophan → heme electron transfer and excitation energy transfer for the two tryptophan residues in myoglobin (Consani et al., Science, 2013, 339, 1586). Here, we show that accurate prediction of these rates can be achieved using Marcus theory in conjunction with time-dependent density functional theory. Key intermediate residues between the donor and acceptor are identified, and in particular the residues Val68 and Ile75 play a critical role in calculations of the electron coupling matrix elements. Our calculations demonstrate how small changes in structure can have a large effect on the rates, and show that the different rates of electron transfer are dictated by the distance between the heme and tryptophan residues, while for excitation energy transfer the orientation of the tryptophan residues relative to the heme is important. © 2017 The Authors Journal of Computational Chemistry Published by Wiley Periodicals, Inc.

  8. Synthesis of Lithium Fluoride from Spent Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Daniela S. Suarez

    2017-05-01

    Full Text Available Lithium (Li is considered a strategic element whose use has significantly expanded. Its current high demand is due to its use in lithium ion batteries for portable electronic devices, whose manufacture and market are extensively growing every day. These days there is a great concern about the final disposal of these batteries. Therefore, the possibility of developing new methodologies to recycle their components is of great importance, both commercially and environmentally. This paper presents results regarding important operational variables for the dissolution of the lithium and cobalt mixed-oxide (LiCoO2 cathodes from spent lithium ion batteries (LIBs with hydrofluoric acid. The recovery and synthesis of Co and Li compounds were also investigated. The dissolution parameters studied were: temperature, reaction time, solid-liquid ratio, stirring speed, and concentration of HF. The investigated recovery parameters included: pH, temperature, and time with and without stirring. The final precipitation of lithium fluoride was also examined. The results indicate that an increase in the HF concentration, temperature, and reaction time favors the leaching reaction of the LiCoO2. Dissolutions were close to 60%, at 75 °C and 120 min with a HF concentration of 25% (v/v. The recovery of Co and Li were 98% and 80%, respectively, with purities higher than 94%. Co and Li compounds, such as Co3O4 and LiF, were synthesized. Furthermore, it was possible to almost completely eliminate the F− ions as CaF2.

  9. Stable local oscillator module.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2007-11-01

    This report gives a description of the development of a Stable Local Oscillator (StaLO) multi-chip module (MCM). It is a follow-on report to SAND2006-6414, Stable Local Oscillator Microcircuit. The StaLO accepts a 100MHz input signal and produces output signals at 1.2, 3.3, and 3.6 GHz. The circuit is built as a multi-chip module (MCM), since it makes use of integrated circuit technologies in silicon and lithium niobate as well as discrete passive components. This report describes the development of an MCM-based version of the complete StaLO, fabricated on an alumina thick film hybrid substrate.

  10. Silicon optical modulators

    Directory of Open Access Journals (Sweden)

    Graham T. Reed

    2005-01-01

    Full Text Available Ever since the earliest research on optical circuits, dating back to the 1970s, there have been visions of an optical superchip (see for example1,2, containing a variety of integrated optical components to carry out light generation, modulation, manipulation, detection, and amplification (Fig. 1. The early work was associated with ferroelectric materials such as lithium niobate (LiNbO3, and III-V semiconductors such as gallium arsenide (GaAs and indium phosphide (InP based systems. LiNbO3 was interesting almost solely because of the fact that it possesses a large electro-optic coefficient3, enabling optical modulation via the Pockels effect. Alternatively, the III-V compounds were interesting because of the relative ease of laser fabrication and the prospect of optical and electronic integration.

  11. Development of the Helium Cooled Lithium Lead blanket for DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Aiello, G., E-mail: giacomo.aiello@cea.fr [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Aubert, J.; Jonquères, N. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Li Puma, A. [CEA-Saclay, DEN/DANS/DM2S/SERMA/LPEC, 91191 Gif Sur Yvette Cedex (France); Morin, A.; Rampal, G. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France)

    2014-10-15

    Highlights: • The HCLL blanket design has been modified to adapt it to the 2012 EFDA DEMO specifications. • The new design has been developed with the aim to capitalize on TBM experience in ITER. • A new attachment system for the modules has been proposed. - Abstract: The Helium Cooled Lithium Lead (HCLL) blanket is one of the candidate European blanket concepts selected for the DEMOnstration fusion power plant that should follow ITER. In a fusion power plant, the blanket is one of the key components because of its impact on the plant performance, availability, safety and economics. In 2012, the European Fusion Development Agreement (EFDA) agency issued new specifications for DEMO: this paper describes the work performed to adapt the previous 2007 HCLL-DEMO blanket design to those specifications. A new segmentation has been defined assuming straight surfaces for all blanket modules. Following the Multi Module Segment (MMS) option, all modules are attached to a common back supporting structure which also serves as manifold for Helium and PbLi distribution. A detailed CAD design of the central outboard module has been defined. Thermo-hydraulic and thermo-mechanical analyses on of the First Wall and Breeder Zone have been carried out. For the attachment of the modules to the common backplate, a new solution based on the use of Tie Rods, derived from the design of the corresponding HCLL Test Blanket Module for ITER, has been proposed. This paper also identifies the priorities for further development of the HCLL blanket design.

  12. Lithium-free transition metal monoxides for positive electrodes in lithium-ion batteries

    Science.gov (United States)

    Jung, Sung-Kyun; Kim, Hyunchul; Cho, Min Gee; Cho, Sung-Pyo; Lee, Byungju; Kim, Hyungsub; Park, Young-Uk; Hong, Jihyun; Park, Kyu-Young; Yoon, Gabin; Seong, Won Mo; Cho, Yongbeom; Oh, Myoung Hwan; Kim, Haegyeom; Gwon, Hyeokjo; Hwang, Insang; Hyeon, Taeghwan; Yoon, Won-Sub; Kang, Kisuk

    2017-01-01

    Lithium-ion batteries based on intercalation compounds have dominated the advanced portable energy storage market. The positive electrode materials in these batteries belong to a material group of lithium-conducting crystals that contain redox-active transition metal and lithium. Materials without lithium-conducting paths or lithium-free compounds could be rarely used as positive electrodes due to the incapability of reversible lithium intercalation or the necessity of using metallic lithium as negative electrodes. These constraints have significantly limited the choice of materials and retarded the development of new positive electrodes in lithium-ion batteries. Here, we demonstrate that lithium-free transition metal monoxides that do not contain lithium-conducting paths in their crystal structure can be converted into high-capacity positive electrodes in the electrochemical cell by initially decorating the monoxide surface with nanosized lithium fluoride. This unusual electrochemical behaviour is attributed to a surface conversion reaction mechanism in contrast with the classic lithium intercalation reaction. Our findings will offer a potential new path in the design of positive electrode materials in lithium-ion batteries.

  13. Gelled Electrolytes For Lithium Batteries

    Science.gov (United States)

    Nagasubramanian, Ganesan; Attia, Alan; Halpert, Gerald

    1993-01-01

    Gelled polymer electrolyte consists of polyacrylonitrile (PAN), LiBF4, and propylene carbonate (PC). Thin films of electrolyte found to exhibit stable bulk conductivities of order of 10 to the negative 3rd power S/cm at room temperature. Used in thinfilm rechargeable lithium batteries having energy densities near 150 W h/kg.

  14. Interfacial reactions in lithium batteries

    Science.gov (United States)

    Chen, Zonghai; Amine, Rachid; Ma, Zi-Feng; Amine, Khalil

    2017-08-01

    The lithium-ion battery was first commercially introduced by Sony Corporation in 1991 using LiCoO2 as the cathode material and mesocarbon microbeads (MCMBs) as the anode material. After continuous research and development for 25 years, lithium-ion batteries have been the dominant energy storage device for modern portable electronics, as well as for emerging applications for electric vehicles and smart grids. It is clear that the success of lithium-ion technologies is rooted to the existence of a solid electrolyte interphase (SEI) that kinetically suppresses parasitic reactions between the lithiated graphitic anodes and the carbonate-based non-aqueous electrolytes. Recently, major attention has been paid to the importance of a similar passivation/protection layer on the surface of cathode materials, aiming for a rational design of high-energy-density lithium-ion batteries with extended cycle/calendar life. In this article, the physical model of the SEI, as well as recent research efforts to understand the nature and role of the SEI are summarized, and future perspectives on this important research field will also be presented.

  15. Molecular dynamics simulation of tryptophan hydroxylase-1: binding modes and free energy analysis to phenylalanine derivative inhibitors.

    Science.gov (United States)

    Zhong, Hao; Huang, Wei; He, Gu; Peng, Cheng; Wu, Fengbo; Ouyang, Liang

    2013-05-10

    Serotonin is a neurotransmitter that modulates many central and peripheral functions. Tryptophan hydroxylase-1 (TPH1) is a key enzyme of serotonin synthesis. In the current study, the interaction mechanism of phenylalanine derivative TPH1 inhibitors was investigated using molecular dynamics (MD) simulations, free energy calculations, free energy decomposition analysis and computational alanine scanning. The predicted binding free energies of these complexes are consistent with the experimental data. The analysis of the individual energy terms indicates that although the van der Waals and electrostatics interaction contributions are important in distinguishing the binding affinities of these inhibitors, the electrostatic contribution plays a more crucial role in that. Moreover, it is observed that different configurations of the naphthalene substituent could form different binding patterns with protein, yet lead to similar inhibitory potency. The combination of different molecular modeling techniques is an efficient way to interpret the interaction mechanism of inhibitors and our work could provide valuable information for the TPH1 inhibitor design in the future.

  16. Molecular Dynamics Simulation of Tryptophan Hydroxylase-1: Binding Modes and Free Energy Analysis to Phenylalanine Derivative Inhibitors

    Directory of Open Access Journals (Sweden)

    Liang Ouyang

    2013-05-01

    Full Text Available Serotonin is a neurotransmitter that modulates many central and peripheral functions. Tryptophan hydroxylase-1 (TPH1 is a key enzyme of serotonin synthesis. In the current study, the interaction mechanism of phenylalanine derivative TPH1 inhibitors was investigated using molecular dynamics (MD simulations, free energy calculations, free energy decomposition analysis and computational alanine scanning. The predicted binding free energies of these complexes are consistent with the experimental data. The analysis of the individual energy terms indicates that although the van der Waals and electrostatics interaction contributions are important in distinguishing the binding affinities of these inhibitors, the electrostatic contribution plays a more crucial role in that. Moreover, it is observed that different configurations of the naphthalene substituent could form different binding patterns with protein, yet lead to similar inhibitory potency. The combination of different molecular modeling techniques is an efficient way to interpret the interaction mechanism of inhibitors and our work could provide valuable information for the TPH1 inhibitor design in the future.

  17. Effect of tryptophan hydroxylase-2 gene polymorphism G-703 T on personality in a population representative sample.

    Science.gov (United States)

    Lehto, Kelli; Vaht, Mariliis; Mäestu, Jarek; Veidebaum, Toomas; Harro, Jaanus

    2015-03-01

    The tryptophan hydroxylase-2 gene (TPH2) is coding for the key enzyme of serotonin (5-HT) synthesis in the brain and has been associated with a number of psychiatric conditions. A functional variation in the TPH2 gene (G-703T, rs4570625) has been found to affect anxiety-related personality; however, information is very limited regarding the five factor model (FFM) personality traits. We have examined the association of the TPH2 G-703T polymorphism with FFM personality traits, and the possible modulation by the functional variation in the serotonin transporter gene (5-HTTLPR) in a large longitudinal population representative sample. The FFM personality traits were assessed in both birth cohorts of the Estonian Children Personality Behaviour and Health Study at ages 15 (n=742) and 18 (n=834). Significant association of the TPH2 genotype with Neuroticism and Conscientiousness was found at age 15, and with Extraversion and Conscientiousness at age 18. Participants with the T/T genotype scored significantly lower on Neuroticism and higher on Conscientiousness and Extraversion scales. In addition, a gene×gene interaction effect on Conscientiousness was revealed: the TPH2 genotype effect was evident only in the 5-HTTLPR S-allele carriers. These results provide further evidence on the possible role of genetic variations in 5-HT neurotransmission on development of personality traits, and suggest a functional interaction between two key proteins in the 5-HT-ergic system.

  18. Regulating the balance between the kynurenine and serotonin pathways of tryptophan metabolism.

    Science.gov (United States)

    Li, Yang; Hu, Nan; Yang, Dan; Oxenkrug, Gregory; Yang, Qing

    2017-03-01

    Tryptophan is metabolized along the kynurenine and serotonin pathways, resulting in formation of kynurenine metabolites, neuroactive serotonin and melatonin. Each pathway is critical for maintaining healthy homeostasis. However, the two pathways are extremely unequal in their ability to degrade tryptophan, and little is known about the mechanisms maintaining the balance between them. Here, we demonstrated that in PC12 cells, a change of expression of key genes of one pathway resulted in a change of expression of key genes of the other. Melatonin, the end product of the serotonin pathway, played an important role in tryptophan metabolism by affecting both key enzymes of the two pathways. Melatonin treatment induced the expression of indole-2,3-dioxygenase 1 (IDO1) and enhanced the activity of the IDO1 promoter while decreasing the expression of arylalkylamine N-acetyl transferase. Melatonin treatment up-regulated the expression of forkhead box protein O1 (FoxO1) and enhanced the binding of FoxO1 to the IDO1 promoter. FoxO1 was shown to be a new regulator for IDO1 expression. Melatonin treatment decreased the phosphorylation of FoxO1 by extracellular signal-regulated kinases 1 and 2 and protein kinase B (Akt) and increased the phosphorylation of binding protein 14-3-3 by c-Jun N-terminal kinase (JNK), and thus the complex of FoxO1-14-3-3 in the cytoplasm was disassembled and FoxO1 was relocated to the nucleus to induce IDO1 expression. The JNK signaling pathway played an important role in melatonin-induced IDO1 up-regulation. In conclusion, this study suggests a link between melatonin, JNK, FoxO1 and IDO1 that acts as a potential balance regulator of tryptophan metabolism, and offers a new approach to treat diseases related to dysregulation of tryptophan metabolism. © 2017 Federation of European Biochemical Societies.

  19. Fluorescence imaging of tryptophan and collagen cross-links to evaluate wound closure ex vivo

    Science.gov (United States)

    Wang, Ying; Ortega-Martinez, Antonio; Farinelli, Bill; Anderson, R. R.; Franco, Walfre

    2016-02-01

    Wound size is a key parameter in monitoring healing. Current methods to measure wound size are often subjective, time-consuming and marginally invasive. Recently, we developed a non-invasive, non-contact, fast and simple but robust fluorescence imaging (u-FEI) method to monitor the healing of skin wounds. This method exploits the fluorescence of native molecules to tissue as functional and structural markers. The objective of the present study is to demonstrate the feasibility of using variations in the fluorescence intensity of tryptophan and cross-links of collagen to evaluate proliferation of keratinocyte cells and quantitate size of wound during healing, respectively. Circular dermal wounds were created in ex vivo human skin and cultured in different media. Two serial fluorescence images of tryptophan and collagen cross-links were acquired every two days. Histology and immunohistology were used to validate correlation between fluorescence and epithelialization. Images of collagen cross-links show fluorescence of the exposed dermis and, hence, are a measure of wound area. Images of tryptophan show higher fluorescence intensity of proliferating keratinocytes forming new epithelium, as compared to surrounding keratinocytes not involved in epithelialization. These images are complementary since collagen cross-links report on structure while tryptophan reports on function. HE and immunohistology show that tryptophan fluorescence correlates with newly formed epidermis. We have established a fluorescence imaging method for studying epithelialization processes during wound healing in a skin organ culture model, our approach has the potential to provide a non-invasive, non-contact, quick, objective and direct method for quantitative measurements in wound healing in vivo.

  20. The tryptophan/kynurenine pathway, systemic inflammation, and long-term outcome after kidney transplantation.

    Science.gov (United States)

    de Vries, Laura V; Minović, Isidor; Franssen, Casper F M; van Faassen, Martijn; Sanders, Jan-Stephan F; Berger, Stefan P; Navis, Gerjan; Kema, Ido P; Bakker, Stephan J L

    2017-08-01

    Tryptophan is metabolized along the kynurenine pathway, initially to kynurenine, and subsequently to cytotoxic 3-hydroxykynurenine. There is increasing interest in this pathway because of its proinflammatory nature, and drugs interfering in it have received increasing attention. We aimed to investigate whether serum and urinary parameters of the tryptophan/kynurenine pathway, and particularly cytotoxic 3-hydroxykynurenine, are associated with systemic inflammation and long-term outcome in renal transplant recipients (RTR). Data were collected in outpatient RTR with a functioning graft for >1 yr. Tryptophan, kynurenine, and 3-hydroxykynurenine in serum and urine were measured using LC-MS/MS. A total of 561 RTR (age: 51 ± 12 yr; 56% male) were included at a median of 6.0 (2.6-11.6) yr posttransplantation. Baseline median serum tryptophan was 40.0 (34.5-46.0) µmol/l, serum kynurenine was 1.8 (1.4-2.2) µmol/l, and serum 3-hydroxykynurenine was 42.2 (31.0-61.7) nmol/l. Serum kynurenine and 3-hydroxykynurenine were strongly associated with parameters of systemic inflammation. During follow-up for 7.0 (6.2-7.5) yr, 51 RTR (9%) developed graft failure and 120 RTR (21%) died. Both serum kynurenine and 3-hydroxykynurenine were independently associated with graft failure [HR 1.72 (1.23-2.41), P = 0.002; and HR 2.03 (1.42-2.90), P inflammation and prospectively with adverse long-term outcome after kidney transplantation. Serum 3-hydroxykynurenine may be an interesting biomarker and target for the evaluation of drugs interfering in the tryptophan/kynurenine pathway. Copyright © 2017 the American Physiological Society.

  1. Primary lithium cell life studies

    Science.gov (United States)

    Capulli, John; Donley, Sam; Deligiannis, Frank; Shen, David

    1990-01-01

    One solution for providing a truly independent power source is to package, within the critical subsystem element, a primary battery that can remain dormant for time periods as long as the mission life, which can be 10-15 years, maximum. When primary power from the spacecraft solar array/battery system is interrupted, the backup battery system, which is connected through a diode to the power input line, would automatically support the load to avoid a power interruption to the critical load for a time period long enough to ensure that ground control could access the satellite and correct the anomaly by sending appropriate commands to the spacecraft. Critical subsystems identified for the application are telemetry and command circuits, volatile computer memory, attitude control circuits, and some critical payloads. Due to volume packaging and weight restrictions that exist on most spacecraft, coupled with the long storage periods required, lithium cell technology was selected for the backup power source. Because of the high energy density (200-400 Wh/kg), long shelf life, and load capability, soluble cathode primary lithium technology was chosen. The most important lithium cell properties that require detail characterization for this application are capacity loss, shelf life, and the voltage delay mechanism. These are functions of storage time and temperature. During storage, a passive film builds up on the lithium electrode. The film protects the lithium electrode from progressive capacity decay but requires time to break down when a load is applied. This phenomenon results in a depressed voltage during the period of film breakdown which can last from fractions of a second to minutes.

  2. Effect of lithium therapy on glomerular filtration rate.

    Science.gov (United States)

    Decina, P; Oliver, J A; Sciacca, R R; Colt, E; Fieve, R R

    1983-08-01

    Patients taking lithium had a slightly higher serum creatinine concentration than controls. Creatinine concentration was independent of lithium level or therapy length, suggesting that lithium decreases glomerular filtration but that this effect is small, noncumulative, and of marginal clinical significance.

  3. Sub-structures formed in the excited state are responsible for tryptophan residues fluorescence in β-lactoglobulin.

    Science.gov (United States)

    Albani, Jihad-Rene

    2011-07-01

    Origin of tryptophan residues fluorescence in β-lactoglobulin is analyzed. Fluorescence lifetimes and spectra of β-lactoglobulin solution are measured at pH going from 2 to 12 and in 6 M guanidine. Tryptophan residues emit with three lifetimes at all conditions. Two lifetimes (0.4-0.5 ns and 2-4 ns) are in the same range of those measured for tryptophan free in solution. Lifetimes in the denatured states are lower than those measured in the native state. Pre-exponential values are modified with the protein structure. Data are identical to those already obtained for other proteins. Fluorescence lifetimes characterize internal states of the tryptophan residues (Tryptophan sub-structures) independently of the tryptophan environments, the third lifetime results from the interaction that is occurring between the Trp residues and its environment. Pre-exponential values characterize substructures populations. In conclusion, tryptophan mission occurs from substates generated in the excited state. This is in good agreement with the theory we described in recent works.

  4. Control of Internal and External Short Circuits in Lithium Ion and Lithium Batteries Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has identified needs for compact high-energy-density primary and secondary batteries. Lithium and Lithium Ion cells, respectively, are meeting these needs for...

  5. Repression of a lithium pump as a consequence of lithium ingestion by manic-depressive subjects.

    Science.gov (United States)

    Meltzer, H L; Kassir, S; Dunner, D L; Fieve, R R

    1977-10-20

    The lithium pump in human erythrocyte membranes, which is responsible for extrusion of lithium against a concentration gradient, has been found to be reversibly repressed during periods of lithium carbonate administration. The pump activity of patients prior to lithium therapy is not different from controls. The onset of repression may require several days to several weeks and occurs at specific individual threshold levels of lithium carbonate dosage. Reactivation of the lithium pump occurs sometime after the dosage is discontinued. We postulate that repression of the lithium pump results from systemically available factors which alter membrane structure, and suggest that is such changes also occur in the central nervous system, they may provide insight into one means by which lithium produces its psychotropic affects.

  6. Short- and long-term effects of dietary l-tryptophan supplementation on the neuroendocrine stress response in seawater-reared Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Basic, D.; Krogdahl, T.; Scholden, J.

    2013-01-01

    The essential amino acid l-tryptophan (Trp) is the immediate precursor of the neurotransmitter serotonin (5-HT). Supplementing Trp through diet has been shown to suppress the neuroendocrine stress response in vertebrates including teleosts. In salmonid fish, adjusting to the social environment...... as well as habituation to seawater involves the neuroendocrine stress response, suggesting that such environmental factors may modulate the stress-reducing effects of Trp. To date, studies that have investigated the neuroendocrine effects of dietary Trp have only been conducted in rainbow trout...... (. Oncorhynchus mykiss), a salmonid species, under conditions featuring social isolation in the freshwater environment. Here, we address the effects of dietary Trp on post-stress plasma cortisol and hypothalamic monoamines in seawater-adapted Atlantic salmon (. Salmo salar), reared at densities relevant...

  7. Effects of intraduodenal infusion of L-tryptophan on ad libitum eating, antropyloroduodenal motility, glycemia, insulinemia, and gut peptide secretion in healthy men.

    Science.gov (United States)

    Steinert, Robert E; Luscombe-Marsh, Natalie D; Little, Tanya J; Standfield, Scott; Otto, Bärbel; Horowitz, Michael; Feinle-Bisset, Christine

    2014-09-01

    Changes in gut motor and hormonal function contribute to the eating-inhibitory and glucose-lowering effects of protein. The effect of amino acids, the digestive products of protein, on gastrointestinal function, eating, and glycemia has not been investigated comprehensively. We tested the hypothesis that L-tryptophan (L-Trp) stimulates gastrointestinal motor and hormonal functions, inhibits eating, and modulates glycemia. Design, Settings, Participants, and Intervention: Ten healthy, normal-weight men were studied in randomized, double-blind fashion, each receiving a 90-minute intraduodenal infusion of L-Trp at 0.075 (total 6.75 kcal) or 0.15 (total 13.5 kcal) kcal/min or saline (control). Antropyloroduodenal motility, plasma ghrelin, cholecystokinin, glucagon-like peptide-1, peptide tyrosine tyrosine, insulin, glucagon, blood glucose, and appetite perceptions were measured. Food intake was quantified from a buffet meal after the infusion. Intraduodenal L-Trp suppressed antral pressures (P eating-inhibitory effect.

  8. Melatonin and its precursor, L-tryptophan: influence on pancreatic amylase secretion in vivo and in vitro.

    Science.gov (United States)

    Jaworek, Jolanta; Nawrot, Katarzyna; Konturek, Stanisław J; Leja-Szpak, Anna; Thor, Piotr; Pawlik, Wiesław W

    2004-04-01

    Melatonin, considered as a main pineal product, may be also synthetized in the gastrointestinal tract from L-tryptophan. Melatonin has been recently shown to affect insulin release and its receptors have been characterized in the pancreas however, the effects of melatonin on the pancreatic enzyme secretion have not been examined. The aim of this study was to investigate the effects of melatonin or L-tryptophan on amylase secretion in vivo in anaesthetized rats with pancreato-biliary fistulas, and in vitro using isolated pancreatic acini. Melatonin (1, 5 or 25 mg/kg) or L-tryptophan (10, 50 or 250 mg/kg) given to the rats as a intraperitoneal (i.p.) bolus injection produced significant and dose-dependent increases in pancreatic amylase secretion under basal conditions or following stimulation of enzyme secretion by diversion of bile-pancreatic juice. This was accompanied by a dose-dependent rise in melatonin plasma level. Stimulation of pancreatic enzyme secretion caused by melatonin or L-tryptophan was completely abolished by vagotomy, deactivation of sensory nerves with capsaicin or pretreatment with CCK1 receptor antagonists (tarazepide or L-364,718). Pretreatment with luzindole, an antagonist of melatonin MT(2) receptor failed to affect melatonin- or L-tryptophan-induced amylase secretion. Administration of melatonin (1, 5 or 25 mg/kg i.p.) or L-tryptophan (10, 50 or 250 mg/kg i.p.) to the rats resulted in the dose-dependent increase of cholecystokinin (CCK) plasma immunoreactivity. Enzyme secretion from isolated pancreatic acini was not significantly affected by melatonin or L-tryptophan used at doses of 10(-8) -10(-5) M. We conclude that exogenous melatonin, as well as that produced endogenously from L-tryptophan, stimulates pancreatic enzyme secretion in vivo while increasing CCK release. Stimulatory effect of melatonin or L-tryptophan on the exocrine pancreas involves vagal sensory nerves and the CCK release by these substances.

  9. Interferon gamma blocks the growth of Toxoplasma gondii in human fibroblasts by inducing the host cells to degrade tryptophan.

    Science.gov (United States)

    Pfefferkorn, E R

    1984-01-01

    Treatment of human fibroblasts with human recombinant gamma interferon blocked the growth of Toxoplasma gondii, an obligate intracellular protozoan parasite. Growth of the parasite was measured by a plaque assay 7 days after infection or by the incorporation of [3H]uracil 1 or 2 days after infection. The antitoxoplasma activity induced in the host cells by gamma interferon was strongly dependent upon the tryptophan concentration of the medium. Progressively higher minimal inhibitory concentrations of gamma interferon were observed as the tryptophan concentration in the culture medium was increased. Treatment with gamma interferon did not make the cells impermeable to tryptophan. The kinetics of [3H]tryptophan uptake into the acid-soluble pools of control and gamma interferon-treated cultures were identical during the first 48 sec. Thereafter uptake of [3H]tryptophan into the acid-soluble pool of control fibroblasts reached the expected plateau after 96 sec. In contrast, uptake of [3H]tryptophan continued for at least 12 min in the gamma interferon-treated cultures. At that time, the acid-soluble pool of the gamma interferon-treated cultures contained 8 times the radioactivity of the control cultures. This continued accumulation was the result of rapid intracellular degradation of [3H]tryptophan into kynurenine and N-formylkynurenine that leaked slowly from the cells. These two metabolites were also recovered from the medium of cultures treated for 1 or 2 days with gamma interferon. Human recombinant alpha and beta interferons, which have no antitoxoplasma activity, did not induce any detectable degradation of tryptophan. Several hypotheses are presented to explain how the intracellular degradation of tryptophan induced by gamma interferon could restrict the growth of an obligate intracellular parasite. Images PMID:6422465

  10. Lithium kan anvendes til patienter i hæmodialyse

    DEFF Research Database (Denmark)

    Kancir, Anne Sophie Pinholt; Viftrup, Jens Emil; Pedersen, Erling Bjerregaard

    2015-01-01

    Lithium-induced nephropathy is a known complication of lithium treatment in bipolar disorder. Treatment with lithium should be discontinued, if there is evidence of lithium-induced nephropathy. However, lithium can be given to patients with end-stage-renal-disease on haemodialysis treatment......, if there is no other way to control the bipolar disorder. We report one patient who was successfully treated with lithium in parallel with haemodialysis....

  11. Repression and reactivation of lithium efflux from erythrocytes.

    Science.gov (United States)

    Goodnick, P J; Meltzer, H L; Dunner, D L; Fieve, R R

    1979-10-01

    Efflux of lithium from human erythrocytes was studied in patients before, during, and after discontinuation of administration of lithium carbonate. Onset of lithium-induced repression of efflux took approximately 10 days and was significantly shorter in patients who had had lithium therapy previously. Reactivation took a longer period of time--approximately 2 week--and was found to be related to duration of lithium therapy. Theoretical pathways of lithium flow through membranes are discussed.

  12. [Lithium can be given to patients on haemodialysis treatment].

    Science.gov (United States)

    Kancir, Anne Sophie Pinholt; Viftrup, Jens Emil; Pedersen, Erling Bjerregaard

    2015-01-26

    Lithium-induced nephropathy is a known complication of lithium treatment in bipolar disorder. Treatment with lithium should be discontinued, if there is evidence of lithium-induced nephropathy. However, lithium can be given to patients with end-stage-renal-disease on haemodialysis treatment, if there is no other way to control the bipolar disorder. We report one patient who was successfully treated with lithium in parallel with haemodialysis.

  13. Wnt and lithium: a common destiny in the therapy of nervous system pathologies?

    Science.gov (United States)

    Meffre, Delphine; Grenier, Julien; Bernard, Sophie; Courtin, Françoise; Dudev, Todor; Shackleford, Ghjuvan'Ghjacumu; Jafarian-Tehrani, Mehrnaz; Massaad, Charbel

    2014-04-01

    Wnt signaling is required for neurogenesis, the fate of neural progenitors, the formation of neuronal circuits during development, neuron positioning and polarization, axon and dendrite development and finally for synaptogenesis. This signaling pathway is also implicated in the generation and differentiation of glial cells. In this review, we describe the mechanisms of action of Wnt signaling pathways and their implication in the development and correct functioning of the nervous system. We also illustrate how a dysregulated Wnt pathway could lead to psychiatric, neurodegenerative and demyelinating pathologies. Lithium, used for the treatment of bipolar disease, inhibits GSK3β, a central enzyme of the Wnt/β-catenin pathway. Thus, lithium could, to some extent, mimic Wnt pathway. We highlight the possible dialogue between lithium therapy and modulation of Wnt pathway in the treatment of the diseases of the nervous system.

  14. Explosion of lithium-thionyl-chloride battery due to presence of lithium nitride

    OpenAIRE

    Hennesø, E.; Hedlund, Frank Huess

    2015-01-01

    An explosion of a lithium–thionyl-chloride (Li–SOCl2) battery during production (assembly) leads to serious worker injury. The accident cell batch had been in a dry-air intermediate storage room for months before being readied with thionyl chloride electrolyte. Metallic lithium can react with atmospheric nitrogen to produce lithium nitride. Nodules of lithium nitride were found to be present on the lithium foil in other cells of the accident batch. The investigation attributed the explosion t...

  15. Lithium and suicide prevention in bipolar disorder.

    Science.gov (United States)

    Benard, V; Vaiva, G; Masson, M; Geoffroy, P A

    2016-06-01

    Bipolar disorder (BD) is a severe and recurrent psychiatric disorder. The severity of prognosis in BD is mainly linked to the high rate of suicide in this population. Indeed, patients with BD commit suicide 20 to 30 times more frequently than the general population, and half of the BD population with an early age of onset have a history of suicide attempt. International therapeutic guidelines recommend lithium (Li) as the first-line treatment in BD for its prophylactic action on depressive or manic episodes. In addition, Li is the only mood stabilizer that has demonstrated efficacy in suicide prevention. This effect of Li is unfortunately often unknown to psychiatrists. Thus, this review aims to highlight evidence about the preventive action of Li on suicide in BD populations. We conducted a literature search between April 1968 and August 2014 in PubMed database using the following terms: "lithium" AND "suicide" OR "suicidality" OR "suicide attempt". As confirmed by a recent meta-analysis, many studies show that Li has a significant effect on the reduction of suicide attempts and deaths by suicide in comparison to antidepressants or other mood-stabilisers in BD populations. Studies have demonstrated that long-term treatment with Li reduces suicide attempts by about 10% and deaths by suicide by about 20%. The combination of Li and an antidepressant could reduce suicidal behaviours by reducing suicidal ideation prior to depressive symptoms. It appears crucial for Li efficacy in suicide prevention to maintain the Li blood concentrations in the efficient therapeutic zone and to instate long-term Li treatment. The "impulsive-aggressive" endophenotype is associated with suicide in BD. The specific action of Li on the 5-HT serotoninergic system could explain the specific anti-suicidal effects of Li via the modulation of impulsiveness and aggressiveness. Furthermore, genetic variants of the glycogen synthase kinase 3α/β (GSK3α and β; proteins inhibited by Li) seem to

  16. Structure and Activity of an Aminoacyl-tRNA Synthetase that Charges tRNA with Nitro-Tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Buddha,M.; Crane, B.

    2005-01-01

    The most divergent of two tryptophanyl tRNA synthetases (TrpRS II) found in Deinococcus radiodurans interacts with a nitric oxide synthase protein that produces 4-nitro-tryptophan (4-NRP). TrpRS II efficiently charges transfer RNATrp with 4-NRP and 5-hydroxy-tryptophan (5-HRP). The crystal structures of TrpRS II bound to tryptophan and 5-HRP reveal residue substitutions that accommodate modified indoles. A class of auxiliary bacterial TrpRSs conserve this capacity to charge tRNA with nonstandard amino acids.

  17. Decreased serum tryptophan in patients with HIV-1 infection correlates with increased serum neopterin and with neurologic/psychiatric symptoms.

    Science.gov (United States)

    Fuchs, D; Möller, A A; Reibnegger, G; Stöckle, E; Werner, E R; Wachter, H

    1990-01-01

    We investigated serum neopterin, tryptophan, and kynurenine concentrations in 23 HIV-1 seropositive patients (Walter Reed Stage 4-6). Ten patients presented with polyneuropathy and three with dementia, one of the patients with dementia also had polyneuropathy and dementia. We found significant associations between lower trytophan concentrations and neurologic/psychiatric symptoms. The negative correlation of tryptophan with kynurenine and neopterin concentrations indicates activity of indoleamine 2,3-dioxygenase (IDO) in patients. IDO can be induced by cytokines such as interferon-gamma and therefore low tryptophan levels may result from chronic immune stimulation in HIV-1 seropositives.

  18. A Brief Historic Overview of Clinical Disorders Associated with Tryptophan: The Relevance to Chronic Fatigue Syndrome (CFS) and Fibromyalgia (FM).

    Science.gov (United States)

    Blankfield, Adele

    2012-01-01

    Last century there was a short burst of interest in the tryptophan related disorders of pellagra and related abnormalities that are usually presented in infancy.1,2 Nutritional physiologists recognized that a severe human dietary deficiency of either tryptophan or the B group vitamins could result in central nervous system (CNS) sequelae such as ataxia, cognitive dysfunction and dysphoria, accompanied by skin hyperpigmentation.3,4 The current paper will focus on the emerging role of tryptophan in chronic fatigue syndrome (CFS) and fibromyalgia (FM).

  19. Lithium in drinking water and suicide mortality: The interplay with lithium prescriptions

    NARCIS (Netherlands)

    Helbich, M; Leitner, M; Kapusta, N

    2015-01-01

    Background Little is known about the effects of lithium intake through drinking water on suicide. This intake originates either from natural rock and soil elution and/or accumulation of lithium-based pharmaceuticals in ground water. Aims To examine the interplay between natural lithium in drinking w

  20. Lithium in Stellar Atmospheres: Observations and Theory

    Science.gov (United States)

    Lyubimkov, L. S.

    2016-09-01

    Of all the light elements, lithium is the most sensitive indicator of stellar evolution. This review discusses current data on the abundance of lithium in the atmospheres of A-, F-, G-, and K-stars of different types, as well as the consistency of these data with theoretical predictions. The variety of observed Li abundances is illustrated by the following objects in different stages of evolution: (1) Old stars in the galactic halo, which have a lithium abundance logɛ(Li)=2.2 (the "lithium plateau") that appears to be 0.5 dex lower than the primordial abundance predicted by cosmological models. (2) Young stars in the galactic disk, which have been used to estimate the contemporary initial lithium abundance logɛ(Li)=3.2±0.1 for stars in the Main sequence. Possible sources of lithium enrichment in the interstellar medium during evolution of the galaxy are discussed. (3) Evolving FGK dwarfs in the galactic disk, which have lower logɛ(Li) for lower effective temperature T eff and mass M. The "lithium dip" near T eff ~6600 K in the distribution of logɛ(Li) with respect to T eff in old clusters is discussed. (4) FGK giants and supergiants, of which most have no lithium at all. This phenomenon is consistent with rotating star model calculations. (5) Lithium rich cold giants with logɛ(Li) ≥ 2.0, which form a small, enigmatic group. Theoretical models with rotation can explain the existence of these stars only in the case of low initial rotation velocities V 0 synthesis of lithium (capture of a giant planet is an alternative). (6) Magnetic Ap-stars, where lithium is concentrated in spots located at the magnetic poles. There the lithium abundance reaches logɛ(Li)=6. Discrepancies between observations and theory are noted for almost all the stars discussed in this review.

  1. Liquid electrolytes for lithium and lithium-ion batteries

    Science.gov (United States)

    Blomgren, George E.

    A number of advances in electrolytes have occurred in the past 4 years, which have contributed to increased safety, wider temperature range of operation, better cycling and other enhancements to lithium-ion batteries. The changes to basic electrolyte solutions that have occurred to accomplish these advances are discussed in detail. The solvent components that have led to better low-temperature operation are also considered. Also, additives that have resulted in better structure of the solid electrolyte interphase (SEI) are presented as well as proposed methods of operation of these additives. Other additives that have lessened the flammability of the electrolyte when exposed to air and also caused lowering of the heat of reaction with the oxidized positive electrode are discussed. Finally, additives that act to open current-interrupter devices by releasing a gas under overcharge conditions and those that act to cycle between electrodes to alleviate overcharging are presented. As a class, these new electrolytes are often called "functional electrolytes". Possibilities for further progress in this most important area are presented. Another area of active work in the recent past has been the reemergence of ambient-temperature molten salt electrolytes applied to alkali metal and lithium-ion batteries. This revival of an older field is due to the discovery of new salt types that have a higher voltage window (particularly to positive potentials) and also have greatly increased hydrolytic stability compared to previous ionic liquids. While practical batteries have not yet emerged from these studies, the increase in the number of active researchers and publications in the area demonstrates the interest and potentialities of the field. Progress in the field is briefly reviewed. Finally, recent results on the mechanisms for capacity loss on shelf and cycling in lithium-ion cells are reviewed. Progress towards further market penetration by lithium-ion cells hinges on improved

  2. Short-chain fluorescent tryptophan tags for on-line detection of functional recombinant proteins

    Directory of Open Access Journals (Sweden)

    Siepert Eva-Maria

    2012-09-01

    Full Text Available Abstract Background Conventional fluorescent proteins, such as GFP, its derivatives and flavin mononucleotide based fluorescent proteins (FbFPs are often used as fusion tags for detecting recombinant proteins during cultivation. These reporter tags are state-of-the-art; however, they have some drawbacks, which can make on-line monitoring challenging. It is discussed in the literature that the large molecular size of proteins of the GFP family may stress the host cell metabolism during production. In addition, fluorophore formation of GFP derivatives is oxygen-dependent resulting in a lag-time between expression and fluorescence detection and the maturation of the protein is suppressed under oxygen-limited conditions. On the contrary, FbFPs are also applicable in an oxygen-limited or even anaerobic environment but are still quite large (58% of the size of GFP. Results As an alternative to common fluorescent tags we developed five novel tags based on clustered tryptophan residues, called W-tags. They are only 5-11% of the size of GFP. Based on the property of tryptophan to fluoresce in absence of oxygen it is reasonable to assume that the functionality of our W-tags is also given under anaerobic conditions. We fused these W-tags to a recombinant protein model, the anti-CD30 receptor single-chain fragment variable antibody (scFv Ki-4(scFv and the anti-MucI single-chain fragment variable M12(scFv. During cultivation in Microtiter plates, the overall tryptophan fluorescence intensity of all cultures was measured on-line for monitoring product formation via the different W-tags. After correlation of the scattered light signal representing biomass concentration and tryptophan fluorescence for the uninduced cultures, the fluorescence originating from the biomass was subtracted from the overall tryptophan signal. The resulting signal, thus, represents the product fluorescence of the tagged and untagged antibody fragments. The product fluorescence signal

  3. A lithium-oxygen battery based on lithium superoxide.

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jun; Lee, Yun Jung; Luo, Xiangyi; Lau, Kah Chun; Wen, Jianguo; Wang, Hsien-Hau; Zhai, Dengyun; Miller, Dean; Jeong, Yo-Sub; Park, Jin-Bum; Curtiss, Larry A.; Amine, Khalil

    2016-01-11

    Although the superoxide of lithium (LiO2) is believed to be a key intermediate in Li-O2 batteries leading to the formation of lithium peroxide, LiO2 has never been observed in its pure state. In this work, we provide evidence that use of a cathode based on a reduced graphene oxide with Ir nanoparticles in a Li-O2 battery results in a LiO2 discharge product formed by single electron transfer without further electron transfer or disproportionation to form Li2O2. High energy X-ray diffraction (HE-XRD) patterns indicates the presence of crystalline LiO2 with no evidence of Li2O2 or Li2O. The HEXRD studies as a function of time also show that LiO2 can be stable in its crystalline form after one week of aging in the presence of electrolyte. The results provide evidence that LiO2 is stable enough that it can be repeatedly charged and discharged with a very low charge potential (~3.2 V) and may open the avenue for a lithium superoxide-based battery.

  4. Lithium Metal Anodes for Rechargeable Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Wu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Jiulin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shanghai Jiao Tong Univ. (China); Ding, Fei [Tianjin Inst. of Power Sources (China); Chen, Xilin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nasybulin, Eduard N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhang, Yaohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Harbin Inst. of Technology (China); Zhang, Jiguang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-10-29

    Rechargeable lithium metal batteries have much higher energy density than those of lithium ion batteries using graphite anode. Unfortunately, uncontrollable dendritic lithium growth inherent in these batteries (upon repeated charge/discharge cycling) and limited Coulombic efficiency during lithium deposition/striping has prevented their practical application over the past 40 years. With the emerging of post Li-ion batteries, safe and efficient operation of lithium metal anode has become an enabling technology which may determine the fate of several promising candidates for the next generation of energy storage systems, including rechargeable Li-air battery, Li-S battery, and Li metal battery which utilize lithium intercalation compounds as cathode. In this work, various factors which affect the morphology and Coulombic efficiency of lithium anode will be analyzed. Technologies used to characterize the morphology of lithium deposition and the results obtained by modeling of lithium dendrite growth will also be reviewed. At last, recent development in this filed and urgent need in this field will also be discussed.

  5. Lithium-ion batteries fundamentals and applications

    CERN Document Server

    Wu, Yuping

    2015-01-01

    Lithium-Ion Batteries: Fundamentals and Applications offers a comprehensive treatment of the principles, background, design, production, and use of lithium-ion batteries. Based on a solid foundation of long-term research work, this authoritative monograph:Introduces the underlying theory and history of lithium-ion batteriesDescribes the key components of lithium-ion batteries, including negative and positive electrode materials, electrolytes, and separatorsDiscusses electronic conductive agents, binders, solvents for slurry preparation, positive thermal coefficient (PTC) materials, current col

  6. Lithium-Air Cell Development

    Science.gov (United States)

    Reid, Concha M.; Dobley, Arthur; Seymour, Frasier W.

    2014-01-01

    Lithium-air (Li-air) primary batteries have a theoretical specific capacity of 11,400 Wh/kg, the highest of any common metal-air system. NASA is developing Li-air technology for a Mobile Oxygen Concentrator for Spacecraft Emergencies, an application which requires an extremely lightweight primary battery that can discharge over 24 hours continuously. Several vendors were funded through the NASA SBIR program to develop Li-air technology to fulfill the requirements of this application. New catalysts and carbon cathode structures were developed to enhance the oxygen reduction reaction and increase surface area to improve cell performance. Techniques to stabilize the lithium metal anode surface were explored. Experimental results for prototype laboratory cells are given. Projections are made for the performance of hypothetical cells constructed from the materials that were developed.

  7. Differences in fluorescence profiles from breast cancer tissues due to changes in relative tryptophan content via energy transfer: tryptophan content correlates with histologic grade and tumor size but not with lymph node metastases

    Science.gov (United States)

    Sordillo, Laura A.; Sordillo, Peter P.; Budansky, Yury; Pu, Yang; Alfano, Robert R.

    2014-12-01

    The correlation between histologic grade, an increasingly important measure of prognosis for patients with breast cancer, and tryptophan levels from tissues of 15 breast carcinoma patients was investigated. Changes in the relative content of key native organic biomolecule tryptophan were seen from the fluorescence spectra of cancerous and paired normal tissues with excitation wavelengths of 280 and 300 nm. Due to a large spectral overlap and matching excitation-emission spectra, fluorescence resonance energy transfer from tryptophan-donor to reduced nicotinamide adenine dinucleotides-acceptor was noted. We used the ratios of fluorescence intensities at their spectral emission peaks, or spectral fingerprint peaks, at 340, 440, and 460 nm. Higher ratios correlated strongly with high histologic grade, while lower-grade tumors had low ratios. Large tumor size also correlated with high ratios, while the number of lymph node metastases, a major factor in staging, was not correlated with tryptophan levels. High histologic grade correlates strongly with increased content of tryptophan in breast cancer tissues and suggests that measurement of tryptophan content may be useful as a part of the evaluation of these patients.

  8. Nutritional Evaluation of Glycated Valine and Tryptophan as a Precursor for Protein Synthesis in Chicken Embryo Myoblasts

    National Research Council Canada - National Science Library

    Makino, Ryosuke; Sugahara, Misaki; Kita, Kazumi

    2015-01-01

    Valine and Tryptophan plays a role of being a precursor for protein synthesis. Glycation is a non-enzymatic reaction causing dehydrating condensation between the carbonyl group of glucose and the α...

  9. Nutritional Evaluation of Glycated Valine and Tryptophan as a Precursor for Protein Synthesis in Chicken Embryo Myoblasts

    National Research Council Canada - National Science Library

    Makino, Ryosuke; Sugahara, Misaki; Kita, Kazumi

    2015-01-01

    Valine and Tryptophan play a role of being a precursor for protein synthesis. Glycation is a non-enzymatic reaction causing dehydrating condensation between the carbonyl group of glucose and the α...

  10. Evening intake of α-lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention

    NARCIS (Netherlands)

    Markus, C.R.; Jonkman, L.M.; Lammers, J.H.C.M.; Deutz, N.E.P.; Messer, M.H.; Rigtering, N.

    2005-01-01

    Background: Brain serotonin function is thought to promote sleep regulation and cognitive processes, whereas sleep abnormalities and subsequent behavioral decline are often attributed to deficient brain serotonin activity. Brain uptake of the serotonin precursor tryptophan is dependent on nutrients

  11. Lithium interaction with carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Nalimova, V.A. [Moskovskij Gosudarstvennyj Univ., Moscow (Russian Federation). Khimicheskij Fakul`tet; Sklovsky, D.E. [Moskovskij Gosudarstvennyj Univ., Moscow (Russian Federation). Khimicheskij Fakul`tet; Bondarenko, G.N. [Topcheiv Institute of Petrochemical Synthesis, Leninsky Prospekt, 29, Moscow (Russian Federation); Alvergnat-Gaucher, H. [CRMD, CNRS, Universite d`Orleans, 1B rue de la Ferollerie, 45071, Orleans Cedex 02 (France); Bonnamy, S. [CRMD, CNRS, Universite d`Orleans, 1B rue de la Ferollerie, 45071, Orleans Cedex 02 (France); Beguin, F. [CRMD, CNRS, Universite d`Orleans, 1B rue de la Ferollerie, 45071, Orleans Cedex 02 (France)

    1997-05-01

    Lithium interaction with catalytic carbon nanotubes under high-pressure conditions was studied. A large amount of Li (2Li/C) reacted with the carbon nanotubes forming an intercalation compound (I{sub c}{proportional_to}4.1 A) which follows from X-ray diffraction and IR spectroscopy data. We cannot exclude also the possibility of insertion of a part of Li into the channel of the nanotubes. (orig.)

  12. Primary nucleation of lithium carbonate

    Institute of Scientific and Technical Information of China (English)

    Yuzhu SUN; Xingfu SONG; Jin WANG; Yan LUO; Jianguo YU

    2009-01-01

    A set of laser apparatus was used to explore the induction period and the primary nucleation of lithium carbonate. Results show that the induction period increases with the decrease of supersaturation, temperature and stirring speed. Through the classical theory of primary nucleation, many important properties involved in primary nucleation under different conditions were obtained quantitatively, including the interfacial tension between solid and liquid, contact angle, critical nucleus size, critical nuleation free energy etc.

  13. Lithium battery safety and reliability

    Science.gov (United States)

    Levy, Samuel C.

    Lithium batteries have been used in a variety of applications for a number of years. As their use continues to grow, particularly in the consumer market, a greater emphasis needs to be placed on safety and reliability. There is a useful technique which can help to design cells and batteries having a greater degree of safety and higher reliability. This technique, known as fault tree analysis, can also be useful in determining the cause of unsafe behavior and poor reliability in existing designs.

  14. Electroencephalographic characteristics of lithium hydroxybutyrate.

    Science.gov (United States)

    Saratikov, A S; Zamoshchina, T A

    1986-10-01

    Lithium hydroxybutyrate influence on excitability, functional mobility and frequency range power of the cortex electrograms, midbrain reticular formation, posterior hypothalamus caudate nucleus, dorsal hippocampus, basolateral amygdala and medial thalamus in rabbits has been investigated. It has been shown that the drug suppresses the non-specific activating systems of the midbrain and posterior hypothalamus, intensifies work of the caudatocortical inhibitory mechanisms and the forebrain limbic formations (the hippocampus and amygdala).

  15. High energy density lithium batteries

    CERN Document Server

    Aifantis, Katerina E; Kumar, R Vasant

    2010-01-01

    Cell phones, portable computers and other electronic devices crucially depend on reliable, compact yet powerful batteries. Therefore, intensive research is devoted to improving performance and reducing failure rates. Rechargeable lithium-ion batteries promise significant advancement and high application potential for hybrid vehicles, biomedical devices, and everyday appliances. This monograph provides special focus on the methods and approaches for enhancing the performance of next-generation batteries through the use of nanotechnology. Deeper understanding of the mechanisms and strategies is

  16. Solar photovoltaic charging of lithium-ion batteries

    Science.gov (United States)

    Gibson, Thomas L.; Kelly, Nelson A.

    Solar photovoltaic (PV) charging of batteries was tested by using high efficiency crystalline and amorphous silicon PV modules to recharge lithium-ion battery modules. This testing was performed as a proof of concept for solar PV charging of batteries for electrically powered vehicles. The iron phosphate type lithium-ion batteries were safely charged to their maximum capacity and the thermal hazards associated with overcharging were avoided by the self-regulating design of the solar charging system. The solar energy to battery charge conversion efficiency reached 14.5%, including a PV system efficiency of nearly 15%, and a battery charging efficiency of approximately 100%. This high system efficiency was achieved by directly charging the battery from the PV system with no intervening electronics, and matching the PV maximum power point voltage to the battery charging voltage at the desired maximum state of charge for the battery. It is envisioned that individual homeowners could charge electric and extended-range electric vehicles from residential, roof-mounted solar arrays, and thus power their daily commuting with clean, renewable solar energy.

  17. Utilization of superoxide anion by indoleamine oxygenase-catalyzed tryptophan and indoleamine oxidation.

    Science.gov (United States)

    Hayaishi, O

    1996-01-01

    The following is our current working hypothesis concerning the biological significance of IDO induction. When tissues are invaded by virus, bacteria, or parasites, leukocytes and lymphocytes will accumulate at the site and interferon will be produced by these cells in the inflammatory loci. The interferon thus produced is released and interacts with the cell surface to trigger IDO induction in the same or other types of cells. As a consequence of inflammation, superoxide anion is liberated and serves as a substrate for IDO. Although it is possible that some trytophan metabolites may activate the immune system or act as bacteriostatic agents, available evidence does not support this hypothesis. We therefore tentatively conclude that tryptophan is degraded by IDO and depleted, whereby the growth of viruses, bacteria and certain parasites is inhibited, because tryptophan is the least available and therefore most important essential amino acid for their growth.

  18. Molecular analysis of intragenic recombination at the tryptophan synthetase locus in Neurospora crassa

    Indian Academy of Sciences (India)

    A. Wiest; D. Barchers; M. Eaton; R. Henderson; R. Schnittker; K. Mccluskey

    2013-12-01

    Fifteen different classically generated and mapped mutations at the tryptophan synthetase locus in Neurospora crassa have been characterized to the level of the primary sequence of the gene. This sequence analysis has demonstrated that intragenic recombination is accurate to order mutations within one open reading frame. While classic genetic analysis correctly ordered the mutations, the position of mutations characterized by gene sequence analysis was more accurate. A leaky mutation was found to have a wild-type primary sequence. The presence of unique polymorphisms in the primary sequence of the trp-3 gene from strain 861 confirms that it has a unique history relative to the other strains studied. Most strains that were previously shown to be immunologically nonreactive with antibody preparations raised against tryptophan synthetase protein were shown to have nonsense mutations. This work defines 14 alleles of the N. crassa trp-3 gene.

  19. Tryptophan-Assisted Synthesis Reduces Bimetallic Gold/Silver Nanoparticle Cytotoxicity and Improves Biological Activity

    Directory of Open Access Journals (Sweden)

    Igor O. Shmarakov

    2014-10-01

    Full Text Available Aiming to reduce the potential in vivo hepato-and nephrotoxicity of Ag/Au bimetallic nanoparticles (NPs stabilized by sodium dodecyl sulphate (SDS, an approach involving a simultaneous reduction of silver nitrate and tetrachlorauratic acid using tryptophan (Trp as a reducing/stabilizing agent was applied during NP synthesis. The obtained Ag/Au/Trp NPs (5–15 nm sized were able to form stable aggregates with an average size of 370–450 nm and were potentially less toxic than Ag/Au/SDS in relation to a mouse model system based on clinical biochemical parameters and oxidative damage product estimation. Ag/Au/Trp NPs were shown to exhibit anticancer activity in relation to a Lewis lung carcinoma model. The data generated from the present study support the fact that the use of tryptophan in NP synthesis is effective in attenuating the potential hepatotoxicity and nephrotoxicity of NPs during their in vivo application.

  20. Inhibiting the photosensitized oxidation of anthracene and tryptophan by means of natural antioxidants

    Science.gov (United States)

    Aksenova, N. A.; Vyzhlova, E. N.; Malinovskaya, V. V.; Parfenov, V. V.; Solov'eva, A. B.; Timashev, P. S.

    2013-08-01

    It is shown that model reactions of photosensitized oxidation of anthracene and tryptophan can be used for evaluation and comparison of antioxidant activity of various classes of compounds. Inhibition of the oxidation of substrates in the presence of the familiar antioxidants tocopherol (vitamin E), ascorbic acid (vitamin C), and mixtures of these vitamins with methionine, and in the presence of reputed antioxidants dihydroquercetin and taurine, are considered. It is concluded that all of the above compounds except for taurine have antioxidant properties; i.e., they reduce the rate constants of the photosensitized oxidation of anthracene and tryptophan. It is found that the inhibition of oxidation is associated with the interaction between antioxidants and singlet oxygen. Analysis of the kinetic dependences of the photosensitized oxidation of substrates in the presence of antioxidants reveals that a mixture of vitamins inhibits the process most efficiently, and inhibition occurs at the initial stages due to more active interaction between singlet oxygen and vitamin C

  1. The Effect of Tryptophan on Serotonin-Like Neurons in Duck Cerebellum

    Institute of Scientific and Technical Information of China (English)

    LIU Hua-zhen; TANG Wen-hua; PENG Ke-mei; CHEN Wen-qin; LUO Guan-zhong; WANG Yan; WEI Lan

    2006-01-01

    Healthy Cherry Valley ducks were used in the present study. Different doses of tryptophan were injected intraperitoneallyto them after being fasted 4 h (8:00 a.m.-12:00 a.m.). One hour later, they were deeply anaesthetized and perfused. The cerebellum was removed to make serial paraffin longitudinal sections. The streptavidin-biotin-peroxidase complex (SABC) method was used to study the distribution of serotonin-like neurons in the cerebellum. All films were analysed by using a computer-assisted image analysis system. Serotonin-like neurons are only localized in cerebellar Purkinje cell layer. The optical density averages of serotonin-like neurons in 200 and 100 mg kg-1 group are significantly higher than that of O mg kg-1 group (P<0.01). These results show that serotonin-like neurons are distributed in Purkinje cell layer and that excessive tryptophan can affect the content of serotonin in cerebellum.

  2. Stochastic thermodynamics of a chemical nanomachine: The channeling enzyme tryptophan synthase.

    Science.gov (United States)

    Loutchko, Dimitri; Eisbach, Maximilian; Mikhailov, Alexander S

    2017-01-14

    The enzyme tryptophan synthase is characterized by a complex pattern of allosteric interactions that regulate the catalytic activity of its two subunits and opening or closing of their ligand gates. As a single macromolecule, it implements 13 different reaction steps, with an intermediate product directly channeled from one subunit to another. Based on experimental data, a stochastic model for the operation of tryptophan synthase has been earlier constructed [D. Loutchko, D. Gonze, and A. S. Mikhailov, J. Phys. Chem. B 120, 2179 (2016)]. Here, this model is used to consider stochastic thermodynamics of such a chemical nanomachine. The Gibbs energy landscape of the internal molecular states is determined, the production of entropy and its flow within the enzyme are analyzed, and the information exchange between the subunits resulting from allosteric cross-regulations and channeling is discussed.

  3. Tyrosine- and tryptophan-coated gold nanoparticles inhibit amyloid aggregation of insulin.

    Science.gov (United States)

    Dubey, Kriti; Anand, Bibin G; Badhwar, Rahul; Bagler, Ganesh; Navya, P N; Daima, Hemant Kumar; Kar, Karunakar

    2015-12-01

    Here, we have strategically synthesized stable gold (AuNPs(Tyr), AuNPs(Trp)) and silver (AgNPs(Tyr)) nanoparticles which are surface functionalized with either tyrosine or tryptophan residues and have examined their potential to inhibit amyloid aggregation of insulin. Inhibition of both spontaneous and seed-induced aggregation of insulin was observed in the presence of AuNPs(Tyr), AgNPs(Tyr), and AuNPs(Trp) nanoparticles. These nanoparticles also triggered the disassembly of insulin amyloid fibrils. Surface functionalization of amino acids appears to be important for the inhibition effect since isolated tryptophan and tyrosine molecules did not prevent insulin aggregation. Bioinformatics analysis predicts involvement of tyrosine in H-bonding interactions mediated by its C=O, -NH2, and aromatic moiety. These results offer significant opportunities for developing nanoparticle-based therapeutics against diseases related to protein aggregation.

  4. Lithium ion storage between graphenes

    Directory of Open Access Journals (Sweden)

    Chan Yue

    2011-01-01

    Full Text Available Abstract In this article, we investigate the storage of lithium ions between two parallel graphene sheets using the continuous approximation and the 6-12 Lennard-Jones potential. The continuous approximation assumes that the carbon atoms can be replaced by a uniform distribution across the surface of the graphene sheets so that the total interaction potential can be approximated by performing surface integrations. The number of ion layers determines the major storage characteristics of the battery, and our results show three distinct ionic configurations, namely single, double, and triple ion forming layers between graphenes. The number densities of lithium ions between the two graphenes are estimated from existing semi-empirical molecular orbital calculations, and the graphene sheets giving rise to the triple ion layers admit the largest storage capacity at all temperatures, followed by a marginal decrease of storage capacity for the case of double ion layers. These two configurations exceed the maximum theoretical storage capacity of graphite. Further, on taking into account the charge-discharge property, the double ion layers are the most preferable choice for enhanced lithium storage. Although the single ion layer provides the least charge storage, it turns out to be the most stable configuration at all temperatures. One application of the present study is for the design of future high energy density alkali batteries using graphene sheets as anodes for which an analytical formulation might greatly facilitate rapid computational results.

  5. Identification of a quorum sensing pheromone posttranslationally farnesylated at the internal tryptophan residue from Bacillus subtilis subsp. natto.

    Science.gov (United States)

    Hayashi, Shunsuke; Usami, Syohei; Nakamura, Yuta; Ozaki, Koki; Okada, Masahiro

    2015-01-01

    Bacillus subtilis subsp. natto produces poly-γ-glutamic acid under the control of quorum sensing. We identified ComXnatto pheromone as the quorum-sensing pheromone with an amino acid sequence of Lys-Trp-Pro-Pro-Ile-Glu and the tryptophan residue posttranslationally modified by a farnesyl group. ComXnatto pheromone is unique in the sense that the 5th tryptophan residue from the C-terminal is farnesylated.

  6. Tryptophanase-Catalyzed l-Tryptophan Synthesis from d-Serine in the Presence of Diammonium Hydrogen Phosphate

    OpenAIRE

    Fujii Noriko; Haruka Ozaki; Takeshi Saito; Akihiko Shimada

    2009-01-01

    Tryptophanase, an enzyme with extreme absolute stereospecificity for optically active stereoisomers, catalyzes the synthesis of L-tryptophan from L-serine and indole through a β-substitution mechanism of the ping-pong type, and has no activity on D-serine. We previously reported that tryptophanase changed its stereospecificity to degrade D-tryptophan in highly concentrated diammonium hydrogen phosphate, (NH4)2HPO4 solution. The present study provided the same stereospecific change seen in the...

  7. Indole production by the tryptophanase TnaA in Escherichia coli is determined by the amount of exogenous tryptophan.

    Science.gov (United States)

    Li, Gang; Young, Kevin D

    2013-02-01

    The signalling molecule indole occurs in significant amounts in the mammalian intestinal tract and regulates diverse microbial processes, including bacterial motility, biofilm formation, antibiotic resistance and host cell invasion. In Escherichia coli, the enzyme tryptophanase (TnaA) produces indole from tryptophan, but it is not clear what determines how much indole E. coli can produce and excrete, making it difficult to interpret experiments that investigate the biological effects of indole at high concentrations. Here, we report that the final yield of indole depends directly, and perhaps solely, on the amount of exogenous tryptophan. When supplied with a range of tryptophan concentrations, E. coli converted this amino acid into an equal amount of indole, up to almost 5 mM, an amount well within the range of the highest concentrations so far examined for their physiological effects. Indole production relied heavily on the tryptophan-specific transporter TnaB, even though the alternative transporters AroP and Mtr could import sufficient tryptophan to induce tnaA expression. This TnaB requirement proceeded via tryptophan transport and was not caused by activation of TnaA itself. Bacterial growth was unaffected by the presence of TnaA in the absence of exogenous tryptophan, suggesting that the enzyme does not hydrolyse significant quantities of the internal anabolic amino acid pool. The results imply that E. coli synthesizes TnaA and TnaB mainly, or solely, for the purpose of converting exogenous tryptophan into indole, under conditions and for signalling purposes that remain to be fully elucidated.

  8. Tryptophanase-Catalyzed l-Tryptophan Synthesis from d-Serine in the Presence of Diammonium Hydrogen Phosphate

    OpenAIRE

    Shimada, Akihiko; Ozaki, Haruka; Saito, Takeshi; Fujii, Noriko

    2009-01-01

    Tryptophanase, an enzyme with extreme absolute stereospecificity for optically active stereoisomers, catalyzes the synthesis of l-tryptophan from l-serine and indole through a β-substitution mechanism of the ping-pong type, and has no activity on d-serine. We previously reported that tryptophanase changed its stereospecificity to degrade d-tryptophan in highly concentrated diammonium hydrogen phosphate, (NH4)2HPO4 solution. The present study provided the same stereospecific change seen in the...

  9. Serum Immune System Biomarkers Neopterin and Interleukin-10 Are Strongly Related to Tryptophan Metabolism in Healthy Young Adults.

    Science.gov (United States)

    Deac, Oana M; Mills, James L; Gardiner, Clair M; Shane, Barry; Quinn, Louise; Midttun, Øivind; McCann, Adrian; Meyer, Klaus; Ueland, Per M; Fan, Ruzong; Lu, Zhaohui; Brody, Lawrence C; Molloy, Anne M

    2016-09-01

    Changes in tryptophan metabolism through the vitamin B-6-dependent kynurenine pathway have been linked to activation of the immune system. We hypothesized that blood concentrations of tryptophan and its catabolites were associated with biomarkers relevant to inflammatory processes in healthy noninflamed subjects. Healthy young adults (n = 737) aged 18-28 y without any known diseases or clinical evidence of inflammation provided blood samples for analysis of serum tryptophan/kynurenine metabolites, neopterin, C-reactive protein (CRP), and plasma pyridoxal 5'-phosphate (PLP) with LC-tandem mass spectrometry methodologies. A panel of cytokines was measured in serum by using high-sensitivity ELISA assays. Anthropometric and lifestyle data were collected by questionnaire. Multiple linear regression analysis to determine the effect of measured serum cytokine concentrations as predictors of tryptophan metabolites was performed on inverse normal-rank transformations of the data, adjusted for sex, body mass index, smoking, alcohol intake, and contraceptive use in women. Median serum CRP and neopterin concentrations were well below established clinical cutoffs for inflammation. We observed significant positive associations between serum interleukin-10 (IL-10) and serum kynurenine (P = 0.0002), the kynurenine-to-tryptophan ratio (KTR) (P = 0.003), 3-hydroxykynurenine (P = 0.01), and 3-hydroxyanthranilic acid (P = 0.04). Serum neopterin was positively associated with kynurenine, the KTR (both P < 0.0001), and anthranilic acid (P = 0.004), and was negatively associated with serum tryptophan (P = 0.01) and PLP (P < 0.0001). Serum tumor necrosis factor α was also negatively associated with tryptophan (P < 0.001). In healthy young adults with no apparent inflammatory conditions, serum tryptophan metabolites are significantly associated with key immune system biomarkers. The observed association between IL-10 and kynurenine is unexpected and suggests that kynurenine

  10. EADS-Astrium Lithium Technology Experiences

    Science.gov (United States)

    Mattesco, P.

    2008-09-01

    The Lithium-ion battery has been perceived ten years ago by EADS Astrium as a very promising technology in terms of technical, industrial and cost aspects for satellite platforms with respect to NiCd and NiH2 technologies. In 2008, lithium technology is the baseline for all new spacecrafts, whatever the missions.For telecommunication satellite, since 2003, more than 18 Lithium batteries for Eurostar E3000 platform have been fully tested and integrated (with SAFT VES140S Lithium cells) up to now. 6 E3000 satellites are in orbit equipped with Lithium batteries with more than 4 years in orbit for the first E3000 satellite equipped with Lithium-ion batteries. 7 others E3000 satellites with lithium batteries are currently at various stage of production.For LEO missions (THEOS, PLEIADES…), ABSL batteries with Sony 18650 HC lithium cells will replace, on the latest LEO platform the NiCd technology. The same technology change has been also successfully done previously for scientific missions: since June 2003 for Mars Express and November 2005 for Venus Express.Associated expected system improvements (weight reduction of the battery system, easiest on ground and launch pad management, highest available energy during launch, ….) driven by specific lithium-ion technology features are today demonstrated and in orbit behaviours are as expected [1], [13].The paper will give an overview of experience of EADS-Astrium on lithium battery technology with the description (design, management, architecture) of lithium batteries used on board LEO and GEO satellites. It will give also a picture of the effort done the last ten years to reach this level of experience (test characterisation, simulation…).

  11. The structure of flavin-dependent tryptophan 7-halogenase RebH

    Energy Technology Data Exchange (ETDEWEB)

    Bitto, Eduard; Huang, Yu; Bingman, Craig A.; Singh, Shanteri; Thorson, Jon S.; Phillips, Jr., George N. (UW)

    2010-02-19

    Enzyme catalyzed regio- and stereo-specific halogenations influence the biological activity of a diverse array of therapeutically important natural products, including the antibiotics vancomycin and chloramphenicol as well as the anticancer agents calicheamicin and rebeccamycin. The major class of enzymes responsible for this challenging synthetic reaction, the flavin-dependent halogenases, catalyzes the formation of carbon-halogen bonds using flavin, a halide ion (Cl{sup -}, Br{sup -} or I{sup -}), and O{sub 2}. Recent mechanistic and structural advances achieved with the model flavin-dependent tryptophan 7-halogenases PrnA and RebH have greatly enhanced the level of understanding of this unique reaction. According to these studies, the mechanism for tryptophan halogenation proceeds via FAD(C4a)-OOH activation of a chloride ion into the transient chlorinating species HOCl. The key evidence for the requirement of a transient chlorinating species is the discovery that a {approx}10-{angstrom}-long tunnel separates FAD and tryptophan in the ligand-bound form of PrnA. In a recent compelling study to elucidate the strategy by which RebH controls this highly reactive and indiscriminant oxidant, a Lys79-{var_epsilon}NH-Cl chloramine intermediate was implicated as the actual chlorinating species within RebH and a structural investigation of RebH was reported. Here we report our independent structural analysis of Lechevalieria aerocolonigenes RebH (Uni-Prot accession number Q8KHZ8, 530 amino acids) in its apo-form as well as in a complex with both tryptophan and FAD.

  12. Serum Levels of Tryptophan, 5-Hydroxytryptophan and Serotonin in Patients Affected with Different Forms of Amenorrhea

    Directory of Open Access Journals (Sweden)

    S. Comai

    2010-06-01

    Full Text Available Tryptophan (Trp is present in the serum, partly bound to albumine and in the free form. The unbound portion of circulating tryptophan has the property of crossing the hematoencephalic barrier and being converted within the brain into serotonin (5-HT through the enzymatic processes of hydroxylation and decarboxylation. The serotoninergic system plays an important role in neuroendocrine control of reproductive hormone secretion, and in particular, it may influence GnRH pulsatility, a function essential for reproductive processes. In this study, we analysed serum levels of tryptophan, serotonin and 5-hydroxytryptophan (5-HTP in women with three different forms of amenorrhea: 16 patients were diagnosed with anorexia nervosa, 60 patients with functional hypothalamic amenorrhea, and 14 patients with hyperprolactinemia. Data were compared with those of a group of 25 healthy women. Serum Trp levels were significantly (P ≤ 0.05 lower in the anorexic (11.64 ± 0.53 µg/ml, mean ± S.E. than in the control (12.98 ± 0.37 µg/ml groups. In addition, in the anorexic group a statistical dispersion of Trp values was shown indicating a bimodal data distribution suggesting the existence of two different subgroups of patients. Regarding 5-HTP, an increase of its serum level was observed in all the groups with amenorrhea with the highest value in hyperprolactinemic patients. On the contrary, no statistical differences in serum 5-HT levels among the four analyzed groups were observed. This study shows that women affected by various forms of amenorrhea present an altered metabolism of tryptophan via serotonin and, in particular, markedly high differences are observed between the two subgroups of anorexic patients.

  13. Dynamic Allostery Mediated by a Conserved Tryptophan in the Tec Family Kinases.

    Directory of Open Access Journals (Sweden)

    Nikita Chopra

    2016-03-01

    Full Text Available Bruton's tyrosine kinase (Btk is a Tec family non-receptor tyrosine kinase that plays a critical role in immune signaling and is associated with the immunological disorder X-linked agammaglobulinemia (XLA. Our previous findings showed that the Tec kinases are allosterically activated by the adjacent N-terminal linker. A single tryptophan residue in the N-terminal 17-residue linker mediates allosteric activation, and its mutation to alanine leads to the complete loss of activity. Guided by hydrogen/deuterium exchange mass spectrometry results, we have employed Molecular Dynamics simulations, Principal Component Analysis, Community Analysis and measures of node centrality to understand the details of how a single tryptophan mediates allostery in Btk. A specific tryptophan side chain rotamer promotes the functional dynamic allostery by inducing coordinated motions that spread across the kinase domain. Either a shift in the rotamer population, or a loss of the tryptophan side chain by mutation, drastically changes the coordinated motions and dynamically isolates catalytically important regions of the kinase domain. This work also identifies a new set of residues in the Btk kinase domain with high node centrality values indicating their importance in transmission of dynamics essential for kinase activation. Structurally, these node residues appear in both lobes of the kinase domain. In the N-lobe, high centrality residues wrap around the ATP binding pocket connecting previously described Catalytic-spine residues. In the C-lobe, two high centrality node residues connect the base of the R- and C-spines on the αF-helix. We suggest that the bridging residues that connect the catalytic and regulatory architecture within the kinase domain may be a crucial element in transmitting information about regulatory spine assembly to the catalytic machinery of the catalytic spine and active site.

  14. The effects of tryptophan depletion on impulsivity and mood in healthy men and women

    OpenAIRE

    Walderhaug, Espen

    2007-01-01

    Reduced serotonergic neurotransmission contributes to the pathophysiology of mood disorders, and the majority of modern antidepressants block the serotonin reuptake in the brain. It is also known that people with major depressive disorder are frequently found to have impaired impulse control, and that impulsivity is associated with serotonin. In two separate studies with healthy participants using different designs and a technique called acute tryptophan depletion, which decreases seroton...

  15. Uremic anorexia: a consequence of persistently high brain serotonin levels? The tryptophan/serotonin disorder hypothesis.

    Science.gov (United States)

    Aguilera, A; Selgas, R; Codoceo, R; Bajo, A

    2000-01-01

    Anorexia is a frequent part of uremic syndrome, contributing to malnutrition in dialysis patients. Many factors have been suggested as responsible for uremic anorexia. In this paper we formulate a new hypothesis to explain the appetite disorders in dialysis patients: "the tryptophan/serotonin disorder hypothesis." We review current knowledge of normal hunger-satiety cycle control and the disorders described in uremic patients. There are four phases in food intake regulation: (1) the gastric phase, during which food induces satiety through gastric distention and satiety peptide release; (2) the post absorptive phase, during which circulating compounds, including glucose and amino acids, cause satiety by hepatic receptors via the vagus nerve; (3) the hepatic phase, during which adenosine triphosphate (ATP) concentration is the main stimulus inducing hunger or satiety, with cytokines inhibiting ATP production; and (4) the central phase, during which appetite is regulated through peripheral (circulating plasma substances and neurotransmitters) and brain stimuli. Brain serotonin is the final target for peripheral mechanisms controlling appetite. High brain serotonin levels and a lower serotonin/dopamine ratio cause anorexia. Plasma and brain amino acid concentrations are recognized factors involved in neurotransmitter synthesis and appetite control. Tryptophan is the substrate of serotonin synthesis. High plasma levels of anorectics such as tryptophan (plasma and brain), cholecystokinin, tumor necrosis factor alpha, interleukin-1, and leptin, and deficiencies of nitric oxide and neuropeptide Y have been described in uremia; all increase intracerebral serotonin. We suggest that brain serotonin hyperproduction due to a uremic-dependent excess of tryptophan may be the final common pathway involved in the genesis of uremic anorexia. Various methods of ameliorating anorexia by decreasing the central effects of serotonin are proposed.

  16. Complete phenotypic recovery of an Alzheimer's disease model by a quinone-tryptophan hybrid aggregation inhibitor.

    Directory of Open Access Journals (Sweden)

    Roni Scherzer-Attali

    Full Text Available The rational design of amyloid oligomer inhibitors is yet an unmet drug development need. Previous studies have identified the role of tryptophan in amyloid recognition, association and inhibition. Furthermore, tryptophan was ranked as the residue with highest amyloidogenic propensity. Other studies have demonstrated that quinones, specifically anthraquinones, can serve as aggregation inhibitors probably due to the dipole interaction of the quinonic ring with aromatic recognition sites within the amyloidogenic proteins. Here, using in vitro, in vivo and in silico tools we describe the synthesis and functional characterization of a rationally designed inhibitor of the Alzheimer's disease-associated beta-amyloid. This compound, 1,4-naphthoquinon-2-yl-L-tryptophan (NQTrp, combines the recognition capacities of both quinone and tryptophan moieties and completely inhibited Abeta oligomerization and fibrillization, as well as the cytotoxic effect of Abeta oligomers towards cultured neuronal cell line. Furthermore, when fed to transgenic Alzheimer's disease Drosophila model it prolonged their life span and completely abolished their defective locomotion. Analysis of the brains of these flies showed a significant reduction in oligomeric species of Abeta while immuno-staining of the 3(rd instar larval brains showed a significant reduction in Abeta accumulation. Computational studies, as well as NMR and CD spectroscopy provide mechanistic insight into the activity of the compound which is most likely mediated by clamping of the aromatic recognition interface in the central segment of Abeta. Our results demonstrate that interfering with the aromatic core of amyloidogenic peptides is a promising approach for inhibiting various pathogenic species associated with amyloidogenic diseases. The compound NQTrp can serve as a lead for developing a new class of disease modifying drugs for Alzheimer's disease.

  17. Tryptic digestion of the human erythrocyte glucose transporter: effects on ligand binding and tryptophan fluorescence.

    Science.gov (United States)

    May, J M; Qu, Z C; Beechem, J M

    1993-09-21

    The conformation of the human erythrocyte glucose transport protein has been shown to determine its susceptibility to enzymatic cleavage on a large cytoplasmic loop. We took the converse approach and investigated the effects of tryptic digestion on the conformational structure of this protein. Exhaustive tryptic digestion of protein-depleted erythrocyte ghosts decreased the affinity of the residual transporter for cytochalasin B by 3-fold but did not affect the total number of binding sites. Tryptic digestion also increased the affinity of the residual transporter for D-glucose and inward-binding sugar phenyl beta-D-glucopyranoside but decreased that for the outward-binding 4,6-O-ethylidene glucose. These results suggest that tryptic cleavage stabilized the remaining transporter in an inward-facing conformation, but one with decreased affinity for cytochalasin B. The steady-state fluorescence emission scan of the purified reconstituted glucose transport protein was unaffected by tryptic digestion. Addition of increasing concentrations of potassium iodide resulted in linear Stern-Volmer plots, which were also unaffected by prior tryptic digestion. The tryptophan oxidant N-bromosuccinimide was investigated to provide a more sensitive measure of tryptophan environment. This agent irreversibly inhibited 3-O-methylglucose transport in intact erythrocytes and cytochalasin B binding in protein-depleted ghosts, with a half-maximal effect observed for each activity at about 0.3-0.4 nM. Treatment of purified glucose transport protein with N-bromosuccinimide resulted in a time-dependent quench of tryptophan fluorescence, which was resolved into two components by nonlinear regression using global analysis. Tryptic digestion retarded the rate of oxidation of the more slowly reacting class of tryptophans. (ABSTRACT TRUNCATED AT 250 WORDS)

  18. Enhanced synthesis of 5-hydroxy-l-tryptophan through tetrahydropterin regeneration

    OpenAIRE

    Hara, Ryotaro; Kino, Kuniki

    2013-01-01

    5-Hydroxy-l-tryptophan (5-HTP) is a naturally occurring aromatic amino acid present in the seeds of the African plant Griffonia simplicifolia. Although 5-HTP has therapeutic effects in various symptoms, efficient method of producing 5-HTP has not been established. In this study, we developed a novel cofactor regeneration process to achieve enhanced synthesis of 5-HTP by using modified l-phenylalanine 4-hydroxylase of Chromobacterium violaceum. For the synthesis of 5-HTP using Escherichia coli...

  19. Identification of potential sites for tryptophan oxidation in recombinant antibodies using tert-butylhydroperoxide and quantitative LC-MS.

    Directory of Open Access Journals (Sweden)

    Miriam Hensel

    Full Text Available Amino acid oxidation is known to affect the structure, activity, and rate of degradation of proteins. Methionine oxidation is one of the several chemical degradation pathways for recombinant antibodies. In this study, we have identified for the first time a solvent accessible tryptophan residue (Trp-32 in the complementary-determining region (CDR of a recombinant IgG1 antibody susceptible to oxidation under real-time storage and elevated temperature conditions. The degree of light chain Trp-32 oxidation was found to be higher than the oxidation level of the conserved heavy chain Met-429 and the heavy chain Met-107 of the recombinant IgG1 antibody HER2, which have already been identified as being solvent accessible and sensitive to chemical oxidation. In order to reduce the time for simultaneous identification and functional evaluation of potential methionine and tryptophan oxidation sites, a test system employing tert-butylhydroperoxide (TBHP and quantitative LC-MS was developed. The optimized oxidizing conditions allowed us to specifically oxidize the solvent accessible methionine and tryptophan residues that displayed significant oxidation in the real-time stability and elevated temperature study. The achieved degree of tryptophan oxidation was adequate to identify the functional consequence of the tryptophan oxidation by binding studies. In summary, the here presented approach of employing TBHP as oxidizing reagent combined with quantitative LC-MS and binding studies greatly facilitates the efficient identification and functional evaluation of methionine and tryptophan oxidation sites in the CDR of recombinant antibodies.

  20. Mechanism of Inhibition of Novel Tryptophan Hydroxylase Inhibitors Revealed by Co-crystal Structures and Kinetic Analysis.

    Science.gov (United States)

    Cianchetta, Giovanni; Stouch, Terry; Yu, Wangsheng; Shi, Zhi-Cai; Tari, Leslie W; Swanson, Ronald V; Hunter, Michael J; Hoffman, Isaac D; Liu, Qingyun

    2010-04-14

    Trytophan Hydroxylase Type I (TPH1), most abundantly expressed in the gastrointestinal tract, initiates the synthesis of serotonin by catalyzing hydroxylation of tryptophan in the presence of biopterin and oxygen. We have previously described three series of novel, periphery-specific TPH1 inhibitors that selectively deplete serotonin in the gastrointestinal tract. We have now determined co-crystal structures of TPH1 with three of these inhibitors at high resolution. Analysis of the structural data showed that each of the three inhibitors fills the tryptophan binding pocket of TPH1 without reaching into the binding site of the cofactor pterin, and induces major conformational changes of the enzyme. The enzyme-inhibitor complexes assume a compact conformation that is similar to the one in tryptophan complex. Kinetic analysis showed that all three inhibitors are competitive versus the substrate tryptophan, consistent with the structural data that the compounds occupy the tryptophan binding site. On the other hand, all three inhibitors appear to be uncompetitive versus the cofactor 6-methyltetrahydropterin, which is not only consistent with the structural data but also indicate that the hydroxylation reaction follows an ordered binding mechanism in which a productive complex is formed only if tryptophan binds only after pterin, similar to the kinetic mechanisms of tyrosine and phenylalanine hydroxylase.

  1. Insights into transport mechanism from LeuT engineered to transport tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Piscitelli, Chayne L.; Gouaux, Eric (Oregon HSU)

    2012-01-10

    LeuT is a bacterial homologue of the neurotransmitter:sodium symporter (NSS) family and, being the only NSS member to have been structurally characterized by X-ray crystallography, is a model protein for studying transporter structure and mechanism. Transport activity in LeuT was hypothesized to require structural transitions between open-to-out and occluded conformations dependent upon protein:ligand binding complementarity. Here, using crystallographic and functional analysis, we show that binding site modification produces changes in both structure and activity that are consistent with complementarity-dependent structural transitions to the occluded state. The mutation I359Q converts the activity of tryptophan from inhibitor to transportable substrate. This mutation changes the local environment of the binding site, inducing the bound tryptophan to adopt a different conformer than in the wild-type complex. Instead of trapping the transporter open, tryptophan binding now allows the formation of an occluded state. Thus, transport activity is correlated to the ability of the ligand to promote the structural transition to the occluded state, a step in the transport cycle that is dependent on protein:ligand complementarity in the central binding site.

  2. Effect of zinc on the biosynthesis of tryptophan, indol auxins and gibberellins in barely

    Energy Technology Data Exchange (ETDEWEB)

    Masev, N.; Kutacek, M.

    1966-01-01

    The action of zinc on the growth of barley and the biosynthesis of indol compounds and gibberellin-like substances was investigated in a number of concentrations of zinc from doses stimulating growth to toxic doses. The seeds were soaked before sowing in solutions of zinc sulfate (5 x 10/sup -5/ to 5 x 10/sup -1/% Zn), and the plants cultivated for 7 days in water. Lower concentrations of zinc increased both plant growth and the biosynthesis of tryptophan and auxins. At the optimum concentration of 5 x 10/sup -3/% Zn this increase in tryptophan amounted to 241% of the variant without zinc; in substances with an R/sub F/ corresponding to indolyacetic acid, the increase determined by the biological test, was 207% as against the variant without zinc. Higher concentrations of zinc inhibited growth, the tryptophan content was decreased to below that of the control without zinc and the auxin content also fell to below the control values. Zinc also influenced the content of gibberellin-like substances in the plants. At a concentration of 5 x 10/sup -3/% Zn the increase in the growth activity in the gibberellic acid area of the chromatogram was 294% of the variant without zinc. At toxic concentrations of zinc, the content of gibberellin-like substances fell to below that of the controls. The finding that zinc acts simultaneously on the biosynthesis of auxins and gibberellins is also evidence for the common action of growth substances of various chemical types on plant growth.

  3. Negative Impact of Hypoxia on Tryptophan 2,3-Dioxygenase Function

    Directory of Open Access Journals (Sweden)

    Frank Elbers

    2016-01-01

    Full Text Available Tryptophan is an essential amino acid for hosts and pathogens. The liver enzyme tryptophan 2,3-dioxygenase (TDO provokes, by its ability to degrade tryptophan to N-formylkynurenine, the precursor of the immune-relevant kynurenines, direct and indirect antimicrobial and immunoregulatory states. Up to now these TDO-mediated broad-spectrum effector functions have never been observed under hypoxia in vitro, although physiologic oxygen concentrations in liver tissue are low, especially in case of infection. Here we analysed recombinant expressed human TDO and ex vivo murine TDO functions under different oxygen conditions and show that TDO-induced restrictions of clinically relevant pathogens (bacteria, parasites and of T cell proliferation are abrogated under hypoxic conditions. We pinpointed the loss of TDO efficiency to the reduction of TDO activity, since cell survival and TDO protein levels were unaffected. In conclusion, the potent antimicrobial as well as immunoregulatory effects of TDO were substantially impaired under hypoxic conditions that pathophysiologically occur in vivo. This might be detrimental for the appropriate host immune response towards relevant pathogens.

  4. Perturbations of tyrosine metabolism promote the indolepyruvate pathway via tryptophan in host and microbiome.

    Science.gov (United States)

    Gertsman, Ilya; Gangoiti, Jon A; Nyhan, William L; Barshop, Bruce A

    2015-03-01

    The drug nitisinone (NTBC) is used to treat tyrosinemia type I, and more recently has been also used for the treatment of another disorder of tyrosine metabolism, alkaptonuria. While studying the dose effects of NTBC treatment on alkaptonuria, untargeted metabolomics revealed perturbations in a completely separate pathway, that of tryptophan metabolism. Significant elevations in several indolic compounds associated with the indolepyruvate pathway of tryptophan metabolism were present in NTBC-treated patient sera and correlated with elevations of an intermediate of tyrosine metabolism. Indolic compounds of this pathway have long been associated with commensal bacterial and plant metabolism. These exogenous sources of indoles have been more recently implicated in affecting mammalian cell function and disease. We studied the correlation of these indolic compounds in other disorders of tyrosine metabolism including tyrosinemia types I and II as well as transient tyrosinemia, and demonstrated that 4-hydroxyphenylpyruvate (4-HPP) was directly responsible for the promotion of this pathway. We then investigated the regulation of the indolepyruvate pathway and the role of 4-HPP further in both mammalian cells and intestinal microbial cultures. We demonstrated that several of the indolic products, including indolepyruvate and indolelactate, were in fact generated by human cell metabolism, while the downstream indole metabolite, indolecarboxaldehyde, was produced exclusively by microbial cultures of human gut flora. This study describes a symbiotic perturbation in host and microbiome tryptophan metabolism in response to elevations related to defects of tyrosine metabolism and concomitant drug treatment.

  5. Peroxidase catalyzed nitration of tryptophan derivatives. Mechanism, products and comparison with chemical nitrating agents.

    Science.gov (United States)

    Sala, Alberto; Nicolis, Stefania; Roncone, Raffaella; Casella, Luigi; Monzani, Enrico

    2004-07-01

    The enzymatic nitration of tryptophan derivatives by oxidation of nitrite has been studied using lactoperoxidase and horseradish peroxidase, and compared with the chemical nitration produced by nitrogen dioxide and peroxynitrite. HPLC, mass spectra and NMR analysis of the mixture of products clearly show that nitration occurs at position 4-, 6-, 7-, and N1 of the indole ring, and nitrosation at position N1. Kinetic studies performed on peroxidase/NO2-/H2O2 systems showed substrate saturation behavior with all the tryptophan derivatives employed. The rate dependence on nitrite concentration was found to be linear with horseradish peroxidase while it exhibited saturation behavior with lactoperoxidase. The composition of the product mixture depends on the nitrating agent. While the production of 4-nitro, 6-nitro, 7-nitro and N1-nitro derivatives follows a similar trend, indicating that they are formed according to a similar mechanism, the ratio between the N1-nitroso derivative and other derivatives depends markedly on the nitrite concentration when tryptophan modification is performed by the peroxidase/H2O2/nitrite systems. Analysis of the data indicates that at low nitrite concentration the enzymatic reaction occurs through the classical peroxidase cycle. At high nitrite concentration the reaction proceeds through a different intermediate that we assume to be a protein bound peroxynitrite species.

  6. Insights into transport mechanism from LeuT engineered to transport tryptophan.

    Science.gov (United States)

    Piscitelli, Chayne L; Gouaux, Eric

    2012-01-04

    LeuT is a bacterial homologue of the neurotransmitter:sodium symporter (NSS) family and, being the only NSS member to have been structurally characterized by X-ray crystallography, is a model protein for studying transporter structure and mechanism. Transport activity in LeuT was hypothesized to require structural transitions between open-to-out and occluded conformations dependent upon protein:ligand binding complementarity. Here, using crystallographic and functional analysis, we show that binding site modification produces changes in both structure and activity that are consistent with complementarity-dependent structural transitions to the occluded state. The mutation I359Q converts the activity of tryptophan from inhibitor to transportable substrate. This mutation changes the local environment of the binding site, inducing the bound tryptophan to adopt a different conformer than in the wild-type complex. Instead of trapping the transporter open, tryptophan binding now allows the formation of an occluded state. Thus, transport activity is correlated to the ability of the ligand to promote the structural transition to the occluded state, a step in the transport cycle that is dependent on protein:ligand complementarity in the central binding site.

  7. Separation of tryptophan enantiomers by ligand-exchange chromatography with novel chiral ionic liquids ligand.

    Science.gov (United States)

    Qing, Haiqun; Jiang, Xinyu; Yu, Jingang

    2014-03-01

    Chiral ionic liquids (CILs) with amino acids as cations have been applied as novel chiral ligands coordinated with Cu(2+) to separate tryptophan enantiomers in ligand exchange chromatography. Four kinds of amino acid ionic liquids, including [L-Pro][CF3COO], [L-Pro][NO3], [L-Pro]2[SO4], and [L-Phe][CF3COO] were successfully synthesized and used for separation of tryptophan enantiomers. To optimize the separation conditions, [L-Pro][CF3COO] was selected as the model ligand. Some factors influencing the efficiency of chiral separation, such as copper ion concentration, CILs concentration, methanol ratio (methanol/H2O, v/v), and pH, were investigated. The obtained optimal separation conditions were as follows: 8.0 mmol/L Cu(OAc)2, 4.0 mmol/L [L-Pro][CF3COO], and 20% (v/v) methanol at pH 3.6. Under the optimum conditions, acceptable enantioseparation of tryptophan enantiomers could be observed with a resolution of 1.89. The results demonstrate the good applicability of CILs with amino acids as cations for chiral separation. Furthermore, a comparative study was also conducted for exploring the mechanism of the CILs as new ligands in ligand exchange chromatography. © 2014 Wiley Periodicals, Inc.

  8. Characterization of the putative tryptophan synthase β-subunit from Mycobacterium tuberculosis

    Institute of Scientific and Technical Information of China (English)

    Hongbo Shen; Yanping Yang; Feifei Wang; Ying Zhang; Naihao Ye; Shengfeng Xu; Honghai Wang

    2009-01-01

    The increasing emergence of drug-resistant tuberculosis (TB)poses a serious threat to the control of this disease.It is in urgent need to develop new TB drugs.Tryptophan biosynthetic pathway plays an important role in the growth and replication of Mycobacterium tuberculosis(Mtb).The β-subunit of tryptophan synthase(TrpB)catalyzes the last step of the tryptophan biosynthetic pathway,and it might be a potential target for TB drug design.In this study,we overexpressed,purified,and characterized the putative TrpB-encoding gene Rv1612 in Mtb H37Rv.Results showed that Mtb His-TrpB optimal enzymatic activity is at pH 7.8 with 0.15 M Na+or 0.18 M Mg2+ at 37℃.Structure analysis indicated that Mtb TrpB exhibited a typical β/α barrel structure.The amino acid residues believed to interact with the enzyme cofactor pyridoxal-5'-phosphate were predicted by homology modeling and structure alignment.The role of these residues in catalytic activity of the Mtb His-TrpB was confirmed by site-directed mutagenesis.These results provided reassuring structural information for drug design based on TrpB.

  9. Stable isotope labeling, in vivo, of D- and L-tryptophan pools in lemna gibba and the low incorporation of label into indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Baldi, B.G. (Dept. of Agriculture, Beltsville, MD (USA)); Maher, B.R. (Univ. of Maryland, College Park (USA)); Slovin, J.P.; Cohen, J.D. (Dept. of Agriculture, Beltsville, MD (USA) Univ. of Maryland, College Park (USA))

    1991-04-01

    The authors present evidence that the role of tryptophan and other potential intermediates in the pathways that could lead to indole derivatives needs to be reexamined. Two lines of Lemna gibba were tested for uptake of ({sup 15}N-indole)-labeled tryptophan isomers and incorporation of that label into free indole-3-acetic acid (IAA). Both lines required levels of L-({sup 15}N)tryptophan 2 to 3 orders of magnitude over endogenous levels in order to obtain measurable incorporation of label into IAA. Labeled L-tryptophan was extractable from plant tissue after feeding and showed no measurable isomerization into D-tryptophan. D-({sup 15}N)trytophan supplied to Lemna at rates of approximately 400 times excess of endogenous D-tryptophan levels (to yield an isotopic enrichment equal to that which allowed detection of the incorporation of L-tryptophan into IAA), did not result in measurable incorporation of label into free IAA. These results demonstrate that L-tryptophan is a more direct precursor to IAA than the D isomer and suggest (a) that the availability of tryptophan in vivo is not a limiting factor in the biosynthesis of IAA, thus implying that other regulatory mechanisms are in operation and (b) that L-tryptophan also may not be a primary precursor to IAA in plants.

  10. Manufacturing of Protected Lithium Electrodes for Advanced Lithium-Air, Lithium-Water & Lithium-Sulfur Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Visco, Steven J

    2015-11-30

    The global demand for rechargeable batteries is large and growing rapidly. Assuming the adoption of electric vehicles continues to increase, the need for smaller, lighter, and less expensive batteries will become even more pressing. In this vein, PolyPlus Battery Company has developed ultra-light high performance batteries based on its proprietary protected lithium electrode (PLE) technology. The Company’s Lithium-Air and Lithium-Seawater batteries have already demonstrated world record performance (verified by third party testing), and we are developing advanced lithium-sulfur batteries which have the potential deliver high performance at low cost. In this program PolyPlus Battery Company teamed with Corning Incorporated to transition the PLE technology from bench top fabrication using manual tooling to a pre- commercial semi-automated pilot line. At the inception of this program PolyPlus worked with a Tier 1 battery manufacturing engineering firm to design and build the first-of-its-kind pilot line for PLE production. The pilot line was shipped and installed in Berkeley, California several months after the start of the program. PolyPlus spent the next two years working with and optimizing the pilot line and now produces all of its PLEs on this line. The optimization process successfully increased the yield, throughput, and quality of PLEs produced on the pilot line. The Corning team focused on fabrication and scale-up of the ceramic membranes that are key to the PLE technology. PolyPlus next demonstrated that it could take Corning membranes through the pilot line process to produce state-of-the-art protected lithium electrodes. In the latter part of the program the Corning team developed alternative membranes targeted for the large rechargeable battery market. PolyPlus is now in discussions with several potential customers for its advanced PLE-enabled batteries, and is building relationships and infrastructure for the transition into manufacturing. It is likely

  11. RECOVERY OF LITHIUM FROM WASTE MATERIALS

    Directory of Open Access Journals (Sweden)

    JITKA JANDOVÁ

    2012-03-01

    Full Text Available In this study, processes based on roasting-leaching-crystallization steps and condensation-precipitation steps for Li2CO3 separation from spent Li/MnO2 batteries and lithium-containing wastewaters were developed and verified on a laboratory scale. Spent Li/MnO2 batteries were roasted under reduced pressure at 650°C, which split the castings and deactivated the batteries by reduction of LiMnO2 and MnO2 with residual lithium metal and graphite to form MnO and Li2CO3. The resultant lithium carbonate was selectively solubilised in water with manganese remaining in the leach residue. Li2CO3 of 99.5 % purity was obtained after evaporation of 95 % water. Processing of lithium-containing alkaline wastewaters from the production of liquid rubber comprises condensation up to lithium concentration of 12-13 g/l Li and a two-step precipitation of lithium carbonate using CO2 as a precipitation agent. Sparingly soluble Li2CO3 was produced in the second step at 95°C, whilst most impurities remain in the solution. Obtained lithium carbonate products contained on average more than 99.5 % Li2CO3. The lithium precipitation efficiency was about 90 %.

  12. Ionic conduction of lithium hydride single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Pilipenko, G.I.; Oparin, D.V.; Zhuravlev, N.A.; Gavrilov, F.F.

    1987-09-01

    Using the electrical-conductivity- and NMR-measurement- methods, the ionic-conduction mechanism is established in stoichiometric lithium hydride single crystals. The activation energies of migration of anion- and cation-vacancies and the formation of Schottky-pair defects are determined. They assume that the mechanisms of self-diffusion and conductivity are different in lithium hydride.

  13. Patterns and clinical outcomes of lithium treatment

    NARCIS (Netherlands)

    Wilting, I.

    2008-01-01

    Patterns and consequences of lithium use’. In chapter 2.1 we studied lithium use patterns in out-patients within the last decade. In line with the increase in alternatives and the Dutch guidelines, we observed an increase in use of atypical antipsychotics and valproic acid and a decrease in use tric

  14. Lithium use and the risk of fractures

    NARCIS (Netherlands)

    Wilting, Ingeborg; de Vries, Frank; Thio, Brahm M. K. S.; Cooper, Cyrus; Heerdink, Eibert R.; Leutkens, Hubert G. M.; Nolen, Willem A.; Egberts, Antoine C. G.; van Staa, Tjeerd P.

    A recent study reported a decreased risk of fractures among lithium users. We conducted a case-control study within the UK General Practice Research Database, comparing never, ever, current, recent and past lithium use in 231,778 fracture cases to matched controls. In addition, the risk of fractures

  15. Atomic lithium vapor laser isotope separation

    CERN Document Server

    Olivares, I E

    2002-01-01

    An atomic vapor laser isotope separation in lithium was performed using tunable diode lasers. The method permits also the separation of the isotopes between the sup 6 LiD sub 2 and the sup 7 LiD sub 1 lines using a self-made mass separator which includes a magnetic sector and an ion beam designed for lithium. (Author)

  16. Lithium-Induced Downbeat Nystagmus and Horizontal Gaze Palsy

    DEFF Research Database (Denmark)

    Jørgensen, Jesper Skovlund; Landschoff Lassen, Lisbeth; Wegener, Marianne

    2016-01-01

    We report a case of lithium-induced downbeat nystagmus and horizontal gaze palsy in a 62-year-old woman who was treated for a bipolar affective disorder with lithium carbonate for one month. At presentation serum lithium was within therapeutic range. No alternative causes of the ocular motility...... disturbances were found, and the patient improved significantly as lithium carbonate was discontinued....

  17. Steady-state pharmacokinetics of lithium carbonate in healthy subjects.

    OpenAIRE

    Hunter, R.

    1988-01-01

    1. The pharmacokinetics of lithium in six healthy volunteers stabilised on lithium were investigated and appropriate pharmacokinetic parameters calculated. 2. The results illustrate important differences in single and multiple dose lithium pharmacokinetics; the implications for minimising lithium-induced renal damage are discussed.

  18. Performance Study of optical Modulator based on electrooptic effect

    Science.gov (United States)

    Palodiya, V.; Raghuwanshi, S. K.

    2016-08-01

    In this paper, we have studied and derive performance parameter of highly integrated Lithium Niobate optical modulator. This is a chirp free modulator having low switching voltage and large bandwidth. For an external modulator in which travelling-wave electrodes length L imposed the modulating switching voltage, the product of Vπ and L is fixed for a given electro optic material Lithium Niobate. We investigate to achieve a low Vπ by both magnitude of the electro-optic coefficient for a wide variety of electro-optic materials. A Sellmeier equation for the extraordinary index of congruent lithium niobate is derived. For phase-matching, predictions are accmate for temperature between room temperature 250°C and wavelength ranging from 0.4 to 5µm. The Sellmeier equations predict more accmately refractive indices at long wavelengths. Theoretical result is confirmed by simulated results. We have analysed the various parameters such as switching voltage, device performance index, time constant, transmittance, cut-off frequency, 3-dB bandwidth, power absorption coefficient and transmission bit rate of Lithium Niobate optical Modulator based on electro -optic effect.

  19. Effect of increasing the dietary tryptophan to lysine ratio on plasma levels of tryptophan, kynurenine and urea and on production traits in weaner pigs experimentally infected with an enterotoxigenic strain of Escherichia coli.

    Science.gov (United States)

    Capozzalo, Meeka M; Kim, Jae Cheol; Htoo, John K; de Lange, Cornelius F M; Mullan, Bruce P; Hansen, Christian Fink; Resink, Jan-Willem; Stumbles, Phillip A; Hampson, David J; Pluske, John R

    2015-01-01

    This experiment examined if immune system stimulation of weaner pigs, initiated by inoculation an enterotoxigenic strain of Escherichia coli (ETEC), increased the requirement for dietary tryptophan (Trp), modulated the inflammatory response, altered plasma levels of Trp and its metabolite kynurenine (Kyn) and effected post-weaning diarrhoea. Individually housed pigs (n = 72) weaned at 21 d of age were allocated to one of six treatments (n = 12) according to a two by three factorial arrangement of (1) with or without ETEC infection and (2) three dietary ratios of standardised ileal digestible (SID) Trp to lysine (Lys) (SID Trp:Lys) of 0.16, 0.20 or 0.24, in a completely randomised block design. Pigs had ad libitum access to diets (per kg 14.13 MJ ME, 12.4 g SID Lys, 195 g crude protein) for 3 weeks after weaning. Pigs were infected with ETEC (O149:K98:K88) at 72, 96 and 120 h after weaning and then bled on day 3, 11 and 19. An increased dietary Trp:Lys ratio increased plasma Trp and Kyn (p pigs fed 0.24 SID Trp:Lys had lower levels of plasma urea than at 0.20 Trp:Lys (p = 0.047) and on day 11, plasma urea was lower at 0.20 than at 0.16 SID Trp:Lys (p = 0.007). Infection increased (p = 0.039) the diarrhoea index and deteriorated faecal consistency from day 4-10 (p dietary antibiotic growth promotants, increasing the dietary SID Trp:Lys ratio to 0.24 improved feed conversion ratio after weaning and increased plasma levels of Trp and Kyn regardless of infection with E. coli.

  20. Reactivity of lithium exposed graphite surface

    Energy Technology Data Exchange (ETDEWEB)

    Harilal, S.S., E-mail: sharilal@purdue.edu [Purdue University, School of Nuclear Engineering, 400 Central Dr., West Lafayette, IN 47907 (United States); Allain, J.P.; Hassanein, A. [Purdue University, School of Nuclear Engineering, 400 Central Dr., West Lafayette, IN 47907 (United States); Hendricks, M.R. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Nieto-Perez, M. [CICATA-IPN, Cerro Blanco 141 Cimatario, Queretaro QRO 76090 (Mexico)

    2009-07-30

    Lithium as a plasma-facing component has many attractive features in fusion devices. We investigated chemical properties of the lithiated graphite surfaces during deposition using X-ray photoelectron spectroscopy and low-energy ion scattering spectroscopy. In this study we try to address some of the known issues during lithium deposition, viz., the chemical state of lithium on graphite substrate, oxide layer formation mechanisms, Li passivation effects over time, and chemical change during exposure of the sample to ambient air. X-ray photoelectron studies indicate changes in the chemical composition with various thickness of lithium on graphite during deposition. An oxide layer formation is noticed during lithium deposition even though all the experiments were performed in ultrahigh vacuum. The metal oxide is immediately transformed into carbonate when the deposited sample is exposed to air.

  1. A lithium deposition system for tokamak devices*

    Science.gov (United States)

    Graziul, Christopher; Majeski, Richard; Kaita, Robert; Hoffman, Daniel; Timberlake, John; Card, David

    2002-11-01

    The production of a lithium deposition system using commercially available components is discussed. This system is intended to provide a fresh lithium wall coating between discharges in a tokamak. For this purpose, a film 100-200 Å thick is sufficient to ensure that the plasma interacts solely with the lithium. A test system consisting of a lithium evaporator and a deposition monitor has been designed and constructed to investigate deposition rates and coverage. A Thermionics 3kW e-gun is used to rapidly evaporate small amounts of solid lithium. An Inficon XTM/2 quartz deposition monitor then measures deposition rate at varying distances, positions and angles relative to the e-gun crucible. Initial results from the test system will be presented. *Supported by US DOE contract #DE-AC02-76CH-03073

  2. A safe lithium mimetic for bipolar disorder.

    Science.gov (United States)

    Singh, Nisha; Halliday, Amy C; Thomas, Justyn M; Kuznetsova, Olga V; Baldwin, Rhiannon; Woon, Esther C Y; Aley, Parvinder K; Antoniadou, Ivi; Sharp, Trevor; Vasudevan, Sridhar R; Churchill, Grant C

    2013-01-01

    Lithium is the most effective mood stabilizer for the treatment of bipolar disorder, but it is toxic at only twice the therapeutic dosage and has many undesirable side effects. It is likely that a small molecule could be found with lithium-like efficacy but without toxicity through target-based drug discovery; however, therapeutic target of lithium remains equivocal. Inositol monophosphatase is a possible target but no bioavailable inhibitors exist. Here we report that the antioxidant ebselen inhibits inositol monophosphatase and induces lithium-like effects on mouse behaviour, which are reversed with inositol, consistent with a mechanism involving inhibition of inositol recycling. Ebselen is part of the National Institutes of Health Clinical Collection, a chemical library of bioavailable drugs considered clinically safe but without proven use. Therefore, ebselen represents a lithium mimetic with the potential both to validate inositol monophosphatase inhibition as a treatment for bipolar disorder and to serve as a treatment itself.

  3. A preliminary deposit model for lithium brines

    Science.gov (United States)

    Bradley, Dwight; Munk, LeeAnn; Jochens, Hillary; Hynek, Scott; Labay, Keith A.

    2013-01-01

    This report is part of an effort by the U.S. Geological Survey to update existing mineral deposit models and to develop new ones. The global transition away from hydrocarbons toward energy alternatives increases demand for many scarce metals. Among these is lithium, a key component of lithium-ion batteries for electric and hybrid vehicles. Lithium brine deposits account for about three-fourths of the world’s lithium production. Updating an earlier deposit model, we emphasize geologic information that might directly or indirectly help in exploration for lithium brine deposits, or for assessing regions for mineral resource potential. Special attention is given to the best-known deposit in the world—Clayton Valley, Nevada, and to the giant Salar de Atacama, Chile.

  4. Novel lithium iron phosphate materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, Jelena

    2011-06-15

    Conventional energy sources are diminishing and non-renewable, take million years to form and cause environmental degradation. In the 21st century, we have to aim at achieving sustainable, environmentally friendly and cheap energy supply by employing renewable energy technologies associated with portable energy storage devices. Lithium-ion batteries can repeatedly generate clean energy from stored materials and convert reversely electric into chemical energy. The performance of lithium-ion batteries depends intimately on the properties of their materials. Presently used battery electrodes are expensive to be produced; they offer limited energy storage possibility and are unsafe to be used in larger dimensions restraining the diversity of application, especially in hybrid electric vehicles (HEVs) and electric vehicles (EVs). This thesis presents a major progress in the development of LiFePO4 as a cathode material for lithium-ion batteries. Using simple procedure, a completely novel morphology has been synthesized (mesocrystals of LiFePO4) and excellent electrochemical behavior was recorded (nanostructured LiFePO4). The newly developed reactions for synthesis of LiFePO4 are single-step processes and are taking place in an autoclave at significantly lower temperature (200 deg. C) compared to the conventional solid-state method (multi-step and up to 800 deg. C). The use of inexpensive environmentally benign precursors offers a green manufacturing approach for a large scale production. These newly developed experimental procedures can also be extended to other phospho-olivine materials, such as LiCoPO4 and LiMnPO4. The material with the best electrochemical behavior (nanostructured LiFePO4 with carbon coating) was able to deliver a stable 94% of the theoretically known capacity.

  5. Research and development of lithium batteries in China

    Science.gov (United States)

    Bi, Dao-zhi

    Basic research work on lithium cells in China was initiated in 1965, and a variety of primary cells has been developed and introduced to the market. Lithium-iodine (1978), lithium-thionyl chloride (1977), lithium-sulfur dioxide (1979) and lithium-manganese dioxide (1980) cells, and lithium thermal batteries (1982) have been successfully manufactured and have found wide application. In this paper, the development and the state-of-the-art of various lithium battery systems in China are presented and the present applications and future markets are discussed.

  6. High conducting oxide--sulfide composite lithium superionic conductor

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Chengdu; Rangasamy, Ezhiylmurugan; Dudney, Nancy J.; Keum, Jong Kahk; Rondinone, Adam Justin

    2017-01-17

    A solid electrolyte for a lithium-sulfur battery includes particles of a lithium ion conducting oxide composition embedded within a lithium ion conducting sulfide composition. The lithium ion conducting oxide composition can be Li.sub.7La.sub.3Zr.sub.2O.sub.12 (LLZO). The lithium ion conducting sulfide composition can be .beta.-Li.sub.3PS.sub.4 (LPS). A lithium ion battery and a method of making a solid electrolyte for a lithium ion battery are also disclosed.

  7. Free-standing high quality factor thin-film lithium niobate micro-photonic disk resonators

    CERN Document Server

    Wang, Renyuan

    2014-01-01

    Lithium Niobate (LN or just niobate) thin-film micro-photonic resonators have promising prospects in many applications including high efficiency electro-optic modulators, optomechanics and nonlinear optics. This paper presents free-standing thin-film lithium niobate photonic resonators on a silicon platform using MEMS fabrication technology. We fabricated a 35um radius niobate disk resonator that exhibits high intrinsic optical quality factor (Q) of 484,000. Exploiting the optomechanical interaction from the released free-standing structure and high optical Q, we were able to demonstrate acousto-optic modulation from these devices by exciting a 56MHz radial breathing mechanical mode (mechanical Q of 2700) using a probe.

  8. T4 phage lysozyme: a protein designed for understanding tryptophan photophysics

    Science.gov (United States)

    Hudson, Bruce S.; Harris, Dan

    1990-05-01

    Bacteriophage T4 lysozyme in its wild type form contains three tryptophan residues (at sequence postions 126, 138 and 158). These three residues are in rather different environments in the protein: 126 and 158 are near the protein surface while residue 138 is more buried. T4 lysozyme has been genetically engineered to prepare all possible variants in which one or more of the tryptophan residues have been replaced by tyrosine. The available data supports the hypothesis that this substitution has, at most, a very minor effect on the structure of the protein. The three species with single tryptophan residues have been investigated in detail. The surface location of residue 126 compared to the buried location of residue 138 is reflected in the difference in collisional quenching observed with added potassium iodide. It is found that the spectral and radiative properties of the three proteins are very similar but that their radiationless decay properties are quite distinct. This is apparently due to short-range collisional quenching by neighboring side chains. Comparison with solution quenching measurements permits the identification of the specific quenching groups involved for each tryptophan residue and provides a semi-quantitative rationale for the radiationless decay rate. This collisional quenching interpretation is supported by mutational effects on fluorescence quantum yield. This simple picture of the behavior of these single-tryptophan proteins is clearly revealed in this particular case because of the unambiguous choice of collisional quenching groups. The time dependence of the fluorescence decay of each of these single-tryptophan proteins is quite complex. Several methods of analysis are presented and discussed in terms of their underlying physical basis. Internal collisional quenching, as suggested from the comparative studies, is expected to lead to non-exponential behavior. This is consistent with the observed time dependence. Analysis of the temporal

  9. Advanced Micro/Nanostructures for Lithium Metal Anodes.

    Science.gov (United States)

    Zhang, Rui; Li, Nian-Wu; Cheng, Xin-Bing; Yin, Ya-Xia; Zhang, Qiang; Guo, Yu-Guo

    2017-03-01

    Owning to their very high theoretical capacity, lithium metal anodes are expected to fuel the extensive practical applications in portable electronics and electric vehicles. However, unstable solid electrolyte interphase and lithium dendrite growth during lithium plating/stripping induce poor safety, low Coulombic efficiency, and short span life of lithium metal batteries. Lately, varies of micro/nanostructured lithium metal anodes are proposed to address these issues in lithium metal batteries. With the unique surface, pore, and connecting structures of different nanomaterials, lithium plating/stripping processes have been regulated. Thus the electrochemical properties and lithium morphologies have been significantly improved. These micro/nanostructured lithium metal anodes shed new light on the future applications for lithium metal batteries.

  10. Stable Lithium Deposition Generated from Ceramic-Cross-Linked Gel Polymer Electrolytes for Lithium Anode.

    Science.gov (United States)

    Tsao, Chih-Hao; Hsiao, Yang-Hung; Hsu, Chun-Han; Kuo, Ping-Lin

    2016-06-22

    In this work, a composite gel electrolyte comprising ceramic cross-linker and poly(ethylene oxide) (PEO) matrix is shown to have superior resistance to lithium dendrite growth and be applicable to gel polymer lithium batteries. In contrast to pristine gel electrolyte, these nanocomposite gel electrolytes show good compatibility with liquid electrolytes, wider electrochemical window, and a superior rate and cycling performance. These silica cross-linkers allow the PEO to form the lithium ion pathway and reduce anion mobility. Therefore, the gel not only features lower polarization and interfacial resistance, but also suppresses electrolyte decomposition and lithium corrosion. Further, these nanocomposite gel electrolytes increase the lithium transference number to 0.5, and exhibit superior electrochemical stability up to 5.0 V. Moreover, the lithium cells feature long-term stability and a Coulombic efficiency that can reach 97% after 100 cycles. The SEM image of the lithium metal surface after the cycling test shows that the composite gel electrolyte with 20% silica cross-linker forms a uniform passivation layer on the lithium surface. Accordingly, these features allow this gel polymer electrolyte with ceramic cross-linker to function as a high-performance lithium-ionic conductor and reliable separator for lithium metal batteries.

  11. Comorbidity between depression and inflammatory bowel disease explained by immune-inflammatory, oxidative, and nitrosative stress; tryptophan catabolite; and gut-brain pathways.

    Science.gov (United States)

    Martin-Subero, Marta; Anderson, George; Kanchanatawan, Buranee; Berk, Michael; Maes, Michael

    2016-04-01

    The nature of depression has recently been reconceptualized, being conceived as the clinical expression of activated immune-inflammatory, oxidative, and nitrosative stress (IO&NS) pathways, including tryptophan catabolite (TRYCAT), autoimmune, and gut-brain pathways. IO&NS pathways are similarly integral to the pathogenesis of inflammatory bowel disease (IBD). The increased depression prevalence in IBD associates with a lower quality of life and increased morbidity in IBD, highlighting the role of depression in modulating the pathophysiology of IBD.This review covers data within such a wider conceptualization that better explains the heightened co-occurrence of IBD and depression. Common IO&NS underpinning between both disorders is evidenced by increased pro-inflammatory cytokine levels, eg, interleukin-1 (IL-1) and tumor necrosis factor-α, IL-6 trans-signalling; Th-1- and Th-17-like responses; neopterin and soluble IL-2 receptor levels; positive acute phase reactants (haptoglobin and C-reactive protein); lowered levels of negative acute phase reactants (albumin, transferrin, zinc) and anti-inflammatory cytokines (IL-10 and transforming growth factor-β); increased O&NS with damage to lipids, proteinsm and DNA; increased production of nitric oxide (NO) and inducible NO synthase; lowered plasma tryptophan but increased TRYCAT levels; autoimmune responses; and increased bacterial translocation. As such, heightened IO&NS processes in depression overlap with the biological underpinnings of IBD, potentially explaining their increased co-occurrence. This supports the perspective that there is a spectrum of IO&NS disorders that includes depression, both as an emergent comorbidity and as a contributor to IO&NS processes. Such a frame of reference has treatment implications for IBD when "comorbid" with depression.

  12. Lithium batteries. Citations from the NTIS data base

    Science.gov (United States)

    Cavagnaro, D. M.

    1980-07-01

    Federally funded research on design, development, components, testing corrosion, electrolytes, sealing, hazards of lithium cells are presented. Batteries studied include lithium organic cells, lithium sulfur cells, lithium water air cells, and lithium nickel fluoride cells. Applications cover use in spacecraft, electric vehicles, off peak energy storage, and forklift trucks. This updated bibliography contains 151 citations, 57 of which are new entries to the previous edition.

  13. Pyroelectric generation of 2D spatial soliton sets in a bulk of lithium niobate crystal

    Science.gov (United States)

    Ryabchenok, V.; Shandarov, V.; Perin, A.

    2017-06-01

    The generation of two-dimensional bright spatial soliton sets in lithium niobate sample has been experimentally demonstrated at light wavelength of 532 nm, contribution of pyroelectric effect into nonlinear optical response of the crystal, and spatial modulation of one-dimensional beam along direction normal to the crystal optical axis. Diameters of soliton beams and channel waveguides formed within the crystal bulk by these solitons are near to 20 μm at light polarization corresponding to extraordinary wave of the crystal.

  14. Distinct Patterns of Tryptophan Maintenance in Tissues during Kynurenine Pathway Activation in Simian Immunodeficiency Virus-Infected Macaques

    Directory of Open Access Journals (Sweden)

    Julia L Drewes

    2016-12-01

    Full Text Available Induction of the kynurenine pathway (KP of tryptophan catabolism has been proposed to contribute to T cell dysfunction during human/simian immunodeficiency virus (HIV/SIV infection via depletion of local tryptophan levels and production of immunomodulatory KP metabolites. However, while changes in tryptophan and KP metabolites have been observed in plasma, their levels in lymphoid tissues and levels of enzymes downstream of indoleamine 2,3-dioxygenase (IDO1 have been relatively unexplored. We used our SIV-infected pigtailed macaque model to analyze longitudinal changes in KP metabolites and enzymes by gas chromatography/mass spectrometry and NanoString nCounter gene expression analysis, respectively, in spleen and blood compared to changes previously established in brain and CSF. We found that tryptophan levels were remarkably stable in tissue sites despite robust depletion in the circulating plasma and CSF. We also demonstrated that intracellular tryptophan reserves were maintained in cultured cells even in the presence of depleted extracellular tryptophan levels. Kynurenine, 3-hydroxykynurenine, quinolinic acid, and the KP enzymes all displayed highly divergent patterns in the sites examined, though IDO1 expression always correlated with local kynurenine/tryptophan ratios. Finally, we demonstrated by FACS that myeloid dendritic cells (mDCs and cells of monocytic lineage were the highest producers of IDO1 in chronically infected spleens. Overall our study reveals insights into the tissue-specific regulation of KP enzymes and metabolites and, in particular, highlights the multiple mechanisms by which cells and tissues seek to prevent TRP starvation during inflammation.

  15. Single turnover kinetics of tryptophan hydroxylase: evidence for a new intermediate in the reaction of the aromatic amino acid hydroxylases.

    Science.gov (United States)

    Pavon, Jorge Alex; Eser, Bekir; Huynh, Michaela T; Fitzpatrick, Paul F

    2010-09-07

    Tryptophan hydroxylase (TrpH) uses a non-heme mononuclear iron center to catalyze the tetrahydropterin-dependent hydroxylation of tryptophan to 5-hydroxytryptophan. The reactions of the TrpH.Fe(II), TrpH.Fe(II).tryptophan, TrpH.Fe(II).6MePH(4).tryptophan, and TrpH.Fe(II).6MePH(4).phenylalanine complexes with O(2) were monitored by stopped-flow absorbance spectroscopy and rapid quench methods. The second-order rate constant for the oxidation of TrpH.Fe(II) has a value of 104 M(-1) s(-1) irrespective of the presence of tryptophan. Stopped-flow absorbance analyses of the reaction of the TrpH.Fe(II).6MePH(4).tryptophan complex with oxygen are consistent with the initial step being reversible binding of oxygen, followed by the formation with a rate constant of 65 s(-1) of an intermediate I that has maximal absorbance at 420 nm. The rate constant for decay of I, 4.4 s(-1), matches that for formation of the 4a-hydroxypterin product monitored at 248 nm. Chemical-quench analyses show that 5-hydroxytryptophan forms with a rate constant of 1.3 s(-1) and that overall turnover is limited by a subsequent slow step, presumably product release, with a rate constant of 0.2 s(-1). All of the data with tryptophan as substrate can be described by a five-step mechanism. In contrast, with phenylalanine as substrate, the reaction can be described by three steps: a second-order reaction with oxygen to form I, decay of I as tyrosine forms, and slow product release.

  16. Regular moderate or intense exercise prevents depression-like behavior without change of hippocampal tryptophan content in chronically tryptophan-deficient and stressed mice.

    Directory of Open Access Journals (Sweden)

    Hosung Lee

    Full Text Available Regular exercise has an antidepressant effect in human subjects. Studies using animals have suggested that the antidepressant effect of exercise is attributable to an increase of brain 5-hydroxytryptamine (5-HT; however, the precise mechanism underlying the antidepressant action via exercise is unclear. In contrast, the effect of 5-HT on antidepressant activity has not been clarified, in part because the therapeutic response to antidepressant drugs has a time lag in spite of the rapid increase of brain 5-HT upon administration of these drugs. This study was designed to investigate the contribution of brain 5-HT to the antidepressant effect of exercise. Mice were fed a tryptophan-deficient diet and stressed using chronic unpredictable stress (CUS for 4 weeks with or without the performance of either moderate or intense exercise on a treadmill 3 days per week. The findings demonstrated that the onset of depression-like behavior is attributable not to chronic reduction of 5-HT but to chronic stress. Regular exercise, whether moderate or intense, prevents depression-like behavior with an improvement of adult hippocampal cell proliferation and survival and without the recovery of 5-HT. Concomitantly, the mice that exercised showed increased hippocampal noradrenaline. Regular exercise prevents the impairment of not long-term memory but short-term memory in a 5-HT-reduced state. Together, these findings suggest that: (1 chronic reduction of brain 5-HT may not contribute to the onset of depression-like behavior; (2 regular exercise, whether moderate or intense, prevents the onset of chronic stress-induced depression-like behavior independent of brain 5-HT and dependent on brain adrenaline; and (3 regular exercise prevents chronic tryptophan reduction-induced impairment of not long-term but short-term memory.

  17. Dead lithium phase investigation of Sn-Zn alloy as anode materials for lithium ion battery

    Institute of Scientific and Technical Information of China (English)

    HUANG ZhaoWen; HU SheJun; HOU XianHua; RU Qiang; YU HongWen; ZHAO LingZhi; LI WeiShan

    2009-01-01

    In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through investigation, we found that the phases LixSn4Zn4(x = 2, 4, 6, 8) contributed to reversible capacity, while the phases LixSn4Zns-(x-4)(x = 4.74, 7.72) led to capacity loss due to high formation energy, namely, they were the dead lithium phases during the charge/discharge process. And we come up with a new idea that stable lithium alloy phase with high lithiation formation energy (dead lithium phase) can also result in high loss of active lithium ion, besides the traditional expression that the formation of solid electrolyte interface film leads to high capacity loss.

  18. Mechanism of lithium insertion into NiSi2 anode material for lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    WEN Zhongsheng; JI Shijun; SUN Juncai; TIAN Feng; TIAN Rujin; XIE Jingying

    2006-01-01

    As a promising high capacity anode material for lithium ion batteries, the lithium insertion performance and possible insertion mechanism of binary alloy of NiSi2 were discussed. The initial lithium insertion of crystal NiSi2 can reach up to 600 mAh·g-1 , but large irreversible capacity occurrs simultaneously for serious structure transformation and the irreversible phase forms. XRD and XPS were employed to detect the crystal structure and composition changes produced by lithium insertion. The lithium insertion-extraction behavior of NiSi2 electrode is similar to that of silicon after the first discharge. The structure stability seems related to the non-stoichimometric Ni-Si compound formed by lithium insertion into NiSi2.

  19. Lithium plating in lithium-ion batteries investigated by voltage relaxation and in situ neutron diffraction

    Science.gov (United States)

    von Lüders, Christian; Zinth, Veronika; Erhard, Simon V.; Osswald, Patrick J.; Hofmann, Michael; Gilles, Ralph; Jossen, Andreas

    2017-02-01

    In this work, lithium plating is investigated by means of voltage relaxation and in situ neutron diffraction in commercial lithium-ion batteries. We can directly correlate the voltage curve after the lithium plating with the ongoing phase transformation from LiC12 to LiC6 according to the neutron diffraction data during the relaxation. Above a threshold current of C/2 at a temperature of -2 °C, lithium plating increases dramatically. The results indicate that the intercalation rate of deposited lithium seems to be constant, independent of the deposited amount. It can be observed that the amount of plating correlates with the charging rate, whereas a charging current of C/2 leads to a deposited amount of lithium of 5.5% of the charge capacity and a current of 1C to 9.0%.

  20. Novel polymer electrolyte from poly(carbonate-ether) and lithium tetrafluoroborate for lithium-oxygen battery

    Science.gov (United States)

    Lu, Qi; Gao, Yonggang; Zhao, Qiang; Li, Ji; Wang, Xianhong; Wang, Fosong

    2013-11-01

    Novel polymer electrolyte based on low-molecular weight poly(carbonate-ether) and lithium tetrafluoroborate has been prepared and used in lithium-oxygen battery for the first time, the electrolyte with approximate 17% of LiBF4 showed ionic conductivity of 1.57 mS cm-1. Infrared spectra analysis indicates that obvious interaction between the lithium ions and partial oxygen atoms in the host polymer exists, and the lithium salt and the host polymer have good miscibility. The lithium-oxygen battery from this polymer electrolyte shows similar cyclic stability to traditional liquid electrolyte observed by FT-IR, AFM and electrochemical measurements, which may provide a new choice for fabrication of all-solid-state high-capacity rechargeable lithium-oxygen battery with better safety.