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Sample records for leggettschcn2005 leggett ca

  1. Falsification of Leggett's model using neutron matter waves

    International Nuclear Information System (INIS)

    Hasegawa, Yuji; Sponar, Stephan; Durstberger-Rennhofer, Katharina; Badurek, Gerald; Schmitzer, Claus; Bartosik, Hannes; Klepp, Jürgen

    2012-01-01

    According to Bell's theorem, no theory based on the joint assumption of realism and locality can reproduce certain predictions of quantum mechanics. Another class of realistic models, proposed by Leggett, that demands realism but abandons reliance on locality, is predicted to be in conflict with quantum mechanics. In this paper, we report on an experimental test of a contextual realistic model analogous to the model of Leggett performed with matter waves, more precisely with neutrons. Correlation measurements of the spin-energy entangled single-particle system show violation of a Leggett-type inequality by more than 7.6 standard deviations. Our experimental data falsify the contextual realistic model and are fully in favor of quantum mechanics. (paper)

  2. From Boole to Leggett-Garg: Epistemology of Bell-Type Inequalities

    Directory of Open Access Journals (Sweden)

    Karl Hess

    2016-01-01

    Full Text Available In 1862, George Boole derived an inequality for variables that represents a demarcation line between possible and impossible experience. This inequality forms an important milestone in the epistemology of probability theory and probability measures. In 1985 Leggett and Garg derived a physics related inequality, mathematically identical to Boole’s, that according to them represents a demarcation between macroscopic realism and quantum mechanics. We show that a wide gulf separates the “sense impressions” and corresponding data, as well as the postulates of macroscopic realism, from the mathematical abstractions that are used to derive the inequality of Leggett and Garg. If the gulf can be bridged, one may indeed derive the said inequality, which is then clearly a demarcation between possible and impossible experience: it cannot be violated and is not violated by quantum theory. This implies that the Leggett-Garg inequality does not mean that the SQUID flux is not there when nobody looks, as Leggett and Garg suggest, but instead that the probability measures may not be what Leggett and Garg have assumed them to be, when no data can be secured that directly relate to them. We show that similar considerations apply to other quantum interpretation-puzzles such as two-slit experiments.

  3. Coupling of Higgs and Leggett modes in non-equilibrium superconductors.

    Science.gov (United States)

    Krull, H; Bittner, N; Uhrig, G S; Manske, D; Schnyder, A P

    2016-06-21

    In equilibrium systems amplitude and phase collective modes are decoupled, as they are mutually orthogonal excitations. The direct detection of these Higgs and Leggett collective modes by linear-response measurements is not possible, because they do not couple directly to the electromagnetic field. In this work, using numerical exact simulations we show for the case of two-gap superconductors, that optical pump-probe experiments excite both Higgs and Leggett modes out of equilibrium. We find that this non-adiabatic excitation process introduces a strong interaction between the collective modes, which is absent in equilibrium. Moreover, we propose a type of pump-probe experiment, which allows to probe and coherently control the Higgs and Leggett modes, and thus the order parameter directly. These findings go beyond two-band superconductors and apply to general collective modes in quantum materials.

  4. Anomalous weak values and the violation of a multiple-measurement Leggett-Garg inequality

    Science.gov (United States)

    Avella, Alessio; Piacentini, Fabrizio; Borsarelli, Michelangelo; Barbieri, Marco; Gramegna, Marco; Lussana, Rudi; Villa, Federica; Tosi, Alberto; Degiovanni, Ivo Pietro; Genovese, Marco

    2017-11-01

    Quantum mechanics presents peculiar properties that, on the one hand, have been the subject of several theoretical and experimental studies about its very foundations and, on the other hand, provide tools for developing new technologies, the so-called quantum technologies. The nonclassicality pointed out by Leggett-Garg inequalities has represented, with Bell inequalities, one of the most investigated subjects. In this article we study the connection of Leggett-Garg inequalities with a new emerging field of quantum measurement, the weak values in the case of a series of sequential measurements on a single object. In detail, we perform an experimental study of the four-time-correlator Leggett-Garg test, by exploiting single and sequential weak measurements performed on heralded single photons.

  5. Leggett-Garg inequalities for a quantum top affected by classical noise

    Science.gov (United States)

    Dajka, Jerzy; Łobejko, Marcin; Łuczka, Jerzy

    2016-11-01

    The violation of the Leggett-Garg inequality is studied for a quantum top (with angular momentum J_z of integer or half-integer size), being driven by classical Gaussian white noise. The form of a longitudinal (J_z) or a transverse (J_x) coupling of noise to the angular momentum affects both (i) to what extent the Leggett-Garg inequality is violated and (ii) how this violation is influenced by the size j of the spinning top and direction of a coupling (transverse or longitudinal). We introduce j-independent method, using two- dimensional invariant subspace of the system Hilbert space, which allows us to find out strict analytical solution for a noise-free system and with longitudinal coupling and to extract from the whole dynamics effects purely induced by a noise. It is demonstrated that in the semi-classical limit of a large angular momentum j and for the transverse coupling, the Leggett-Garg inequalities become more strongly violated as compared to the deep quantum regime of small j.

  6. Violation of the quantum regression theorem and the Leggett-Garg inequality in an exactly solvable model

    Science.gov (United States)

    Ban, Masashi

    2017-08-01

    Violation of the quantum regression theorem and the Leggett-Garg inequality is studied by means of the exactly solvable multi-mode Jaynes-Cummings model. An exact expression of a two-time correlation function is compared with that derived by the quantum regression theorem. It is found that the quantum regression theorem is not valid even if the reduced time evolution of the qubit is Markovian. Furthermore, it is shown that if the quantum regression theorem is applied in this model, the Leggett-Garg inequality is satisfied while it is violated by the exact correlation function.

  7. A non-local hidden-variable model that violates Leggett-type inequalities

    International Nuclear Information System (INIS)

    Zela, F de

    2008-01-01

    Recent experiments of Groeblacher et al proved the violation of a Leggett-type inequality that was claimed to be valid for a broad class of non-local hidden-variable theories. The impossibility of constructing a non-local and realistic theory, unless it entails highly counterintuitive features, seems thus to have been experimentally proved. This would bring us close to a definite refutation of realism. Indeed, realism was proved to be also incompatible with locality, according to a series of experiments testing Bell inequalities. The present paper addresses the said experiments of Groeblacher et al and presents an explicit, contextual and realistic, model that reproduces the predictions of quantum mechanics. It thus violates the Leggett-type inequality that was established with the aim of ruling out a supposedly broad class of non-local models. We can thus conclude that plausible contextual, realistic, models are still tenable. This restates the possibility of a future completion of quantum mechanics by a realistic and contextual theory which is not in a class containing only highly counterintuitive models. The class that was ruled out by the experiments of Groeblacher et al is thus proved to be a limited one, arbitrarily separating models that physically belong in the same class

  8. Testing violation of the Leggett-Garg-type inequality in neutrino oscillations of the Daya Bay experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Qiang [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Lanzhou University, Lanzhou (China); University of Chinese Academy of Sciences, Beijing (China); Chen, Xurong [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

    2017-11-15

    The Leggett-Garg inequality (LGI), derived under the assumption of realism, acts as the temporal Bell inequality. It is studied in electromagnetic and strong interaction like photonics, superconducting qubits and nuclear spin. The weak interaction two-state oscillations of neutrinos affirmed the violation of Leggett-Garg-type inequalities (LGtI). We make an empirical test for the deviation of experimental results with the classical limits by analyzing the survival probability data of reactor neutrinos at a distinct range of baseline dividing energies, as an analog to a single neutrino detected at different times. A study of the updated data of the Daya Bay experiment unambiguously depicts an obvious cluster of data over the classical bound of LGtI and shows a 6.1σ significance of the violation of them. (orig.)

  9. The Mayak Worker Dosimetry System (MWDS-2013): a comparison of intakes based on urine versus autopsy data from Mayak workers using the Leggett systemic model for plutonium

    International Nuclear Information System (INIS)

    Birchall, A.; Dorrian, M.-D.; Suslova, K. G.; Sokolova, A. B.

    2017-01-01

    The Mayak Worker Dosimetry System-2013 (MWDS-2013) uses a model developed by Leggett and colleagues to represent the biokinetic behaviour of plutonium after uptake to blood. Of particular importance, with regard to estimating intakes (and doses), is the distribution of activity between urine and body organs (particularly liver and skeleton). In this study, measurement data (urine and autopsy) from around 500 Mayak workers have been used to validate use of this model. A robust method has been developed and used to estimate intakes from both urine and autopsy data separately, and the ratio of these estimates has been calculated for each worker. The geometric mean ratio has been shown to lie within a range of 0.92-1.14, depending on assumptions made. Since this range includes 1, the hypothesis that the model is unbiased with regard to estimating intakes either with urine or autopsy data cannot be rejected on the basis of these data. This lends weight to the argument for increasing the MWDS-2013 cohort to include an additional 500 workers for whom only autopsy data are available, and who have previously been excluded from the cohort. Future directions in which this work could be extended are also suggested. (authors)

  10. Impact of seawater [Ca

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; Thoms, S.; Nehrke, G.; Reichart, G.J.; de Nooijer, L.J.; Bijma, J.

    2015-01-01

    Mg / Ca ratios in foraminiferal tests are routinely used as paleotemperature proxies, but on long timescales, they also hold the potential to reconstruct past seawater Mg / Ca. The impact of both temperature and seawater Mg / Ca on Mg incorporation in Foraminifera has been quantified by a number of

  11. CA-125 blood test

    Science.gov (United States)

    Ovarian cancer - CA-125 test ... CA-125 is a protein that is found more in ovarian cancer cells than in other cells. This ... ovarian cancer . The test is useful if the CA-125 level was high when the cancer was first ...

  12. crdi.ca

    International Development Research Centre (IDRC) Digital Library (Canada)

    et des enfants d'Afrique. INITIATIVE CONCERTÉE. Innovation pour la santé des mères et des enfants d'Afrique. Centre de recherches pour le développement international. CP Box 8500 Ottawa ON Canada K1G 3H9. Téléphone : +1 613 236 6163 • Télécopieur : +1 613 657 7749 ismea@crdi.ca | www.crdi.ca/ismea crdi.ca.

  13. INTRACELLULAR Ca2+ HOMEOSTASIS

    Directory of Open Access Journals (Sweden)

    Shahdevi Nandar Kurniawan

    2015-01-01

    Full Text Available Ca2+ signaling functions to regulate many cellular processes. Dynamics of Ca2+ signaling or homeostasis is regulated by the interaction between ON and OFF reactions that control Ca2+ flux in both the plasma membrane and internal organelles such as the endoplasmic reticulum (ER and mitochondria. External stimuli activate the ON reactions, which include Ca2+ into the cytoplasm either through channels in the plasma membrane or from internal storage like in ER. Most of the cells utilize both channels/sources, butthere area few cells using an external or internal source to control certain processes. Most of the Ca2+ entering the cytoplasm adsorbed to the buffer, while a smaller part activate effect or to stimulate cellular processes. Reaction OFF is pumping of cytoplasmic Ca2+ using a combination mechanism of mitochondrial and others. Changes in Ca2+ signal has been detected in various tissues isolated from animals induced into diabetes as well as patients with diabetes. Ca2+ signal interference is also found in sensory neurons of experimental animals with diabetes. Ca2+ signaling is one of the main signaling systems in the cell.

  14. PIK3CA

    Science.gov (United States)

    Ilic, Nina; Birsoy, Kıvanç; Aguirre, Andrew J; Kory, Nora; Pacold, Michael E; Singh, Shambhavi; Moody, Susan E; DeAngelo, Joseph D; Spardy, Nicole A; Freinkman, Elizaveta; Weir, Barbara A; Tsherniak, Aviad; Cowley, Glenn S; Root, David E; Asara, John M; Vazquez, Francisca; Widlund, Hans R; Sabatini, David M; Hahn, William C

    2017-04-25

    Oncogenic PIK3CA mutations are found in a significant fraction of human cancers, but therapeutic inhibition of PI3K has only shown limited success in clinical trials. To understand how mutant PIK3CA contributes to cancer cell proliferation, we used genome scale loss-of-function screening in a large number of genomically annotated cancer cell lines. As expected, we found that PIK3CA mutant cancer cells require PIK3CA but also require the expression of the TCA cycle enzyme 2-oxoglutarate dehydrogenase (OGDH). To understand the relationship between oncogenic PIK3CA and OGDH function, we interrogated metabolic requirements and found an increased reliance on glucose metabolism to sustain PIK3CA mutant cell proliferation. Functional metabolic studies revealed that OGDH suppression increased levels of the metabolite 2-oxoglutarate (2OG). We found that this increase in 2OG levels, either by OGDH suppression or exogenous 2OG treatment, resulted in aspartate depletion that was specifically manifested as auxotrophy within PIK3CA mutant cells. Reduced levels of aspartate deregulated the malate-aspartate shuttle, which is important for cytoplasmic NAD + regeneration that sustains rapid glucose breakdown through glycolysis. Consequently, because PIK3CA mutant cells exhibit a profound reliance on glucose metabolism, malate-aspartate shuttle deregulation leads to a specific proliferative block due to the inability to maintain NAD + /NADH homeostasis. Together these observations define a precise metabolic vulnerability imposed by a recurrently mutated oncogene.

  15. CAED Document Repository

    Science.gov (United States)

    Compliance Assurance and Enforcement Division Document Repository (CAEDDOCRESP) provides internal and external access of Inspection Records, Enforcement Actions, and National Environmental Protection Act (NEPA) documents to all CAED staff. The respository will also include supporting documents, images, etc.

  16. Ca isotopes in refractory inclusions

    International Nuclear Information System (INIS)

    Niederer, F.R.; Papanastassiou, D.A.

    1984-01-01

    We report measurements of the absolute isotope abundance of Ca in Ca-Al-rich inclusions from the Allende and Leoville meteorites. Improved high precision measurements are reported also for 46 Ca. We find that nonlinear isotope effects in Ca are extremely rare in these inclusions. The absence of nonlinear effects in Ca, except for the effects in FUN inclusions, is in sharp contrast to the endemic effects in Ti. One fine-grained inclusion shows an excess of 46 Ca of (7 +- 1) per mille, which is consistent with addition of only 46 Ca or of an exotic (*) component with 46 Ca* approx. 48 Ca*. FUN inclusion EK-1-4-1 shows a small 46 Ca excess of (3.3 +- 1.0) per mille; this confirms that the exotic Ca components in EK-1-4-1 were even more deficient in 46 Ca relative to 48 Ca than is the case for normal Ca. The Ca in the Ca-Al-rich inclusions shows mass dependent isotope fractionation effects which have a range from -3.8 to +6.7 per mille per mass unit difference. This range is a factor of 20 wider than the range previously established for bulk meteorites and for terrestrial and lunar samples. Ca and Mg isotope fractionation effects in the Ca-Al-rich inclusions are common and attributed to kinetic isotope effects. (author)

  17. Biomarker CA125

    DEFF Research Database (Denmark)

    Kargo, Anette Stolberg

    be detected months before symptoms arise and recurrence is visible on imaging. Therefore, biochemical detection of potential relapse by CA125 assessment can cause significant distress. A decision aid (DA) is a tool that provides information and describes advantages and disadvantages of a specific intervention...... patient organisations and cancer societies. First, a focus group of seven former OC patients was performed followed by a quantitative rating of the DA pilot version. The DA was adapted accordingly and then tested in 14 OC patients with recurrence using a structured interview guide (alpha testing). A final...... agreed that the DA prepared them to make a better decision and helped them reflecting on their concerns regarding CA125. Conclusion: The DA was useful in decision making regarding monitoring CA125 during follow up after OC. The majority of participants indicated that the DA was helpful in clarifying...

  18. Topological organization of CA3-to-CA1 excitation.

    Science.gov (United States)

    Hongo, Yoshie; Ogawa, Koichi; Takahara, Yuji; Takasu, Keiko; Royer, Sebastien; Hasegawa, Minoru; Sakaguchi, Gaku; Ikegaya, Yuji

    2015-09-01

    The CA1-projecting axons of CA3 pyramidal cells, called Schaffer collaterals, constitute one of the major information flow routes in the hippocampal formation. Recent anatomical studies have revealed the non-random structural connectivity between CA3 and CA1, but little is known regarding the functional connectivity (i.e. how CA3 network activity is functionally transmitted downstream to the CA1 network). Using functional multi-neuron calcium imaging of rat hippocampal slices, we monitored the spatiotemporal patterns of spontaneous CA3 and CA1 burst activity under pharmacological GABAergic blockade. We found that spatially clustered CA3 activity patterns were transformed into layered CA1 activity sequences. Specifically, synchronized bursts initiated from multiple hot spots in CA3 ensembles, and CA1 neurons located deeper in the pyramidal cell layer were recruited during earlier phases of the burst events. The order of these sequential activations was maintained across the bursts, but the sequence velocity varied depending on the inter-burst intervals. Thus, CA3 axons innervate CA1 neurons in a highly topographical fashion. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  19. Ca2+ current versus Ca2+ channel cooperativity of exocytosis.

    Science.gov (United States)

    Matveev, Victor; Bertram, Richard; Sherman, Arthur

    2009-09-30

    Recently there has been significant interest and progress in the study of spatiotemporal dynamics of Ca(2+) that triggers exocytosis at a fast chemical synapse, which requires understanding the contribution of individual calcium channels to the release of a single vesicle. Experimental protocols provide insight into this question by probing the sensitivity of exocytosis to Ca(2+) influx. While varying extracellular or intracellular Ca(2+) concentration assesses the intrinsic biochemical Ca(2+) cooperativity of neurotransmitter release, varying the number of open Ca(2+) channels using pharmacological channel block or the tail current titration probes the cooperativity between individual Ca(2+) channels in triggering exocytosis. Despite the wide use of these Ca(2+) sensitivity measurements, their interpretation often relies on heuristic arguments. Here we provide a detailed analysis of the Ca(2+) sensitivity measures probed by these experimental protocols, present simple expressions for special cases, and demonstrate the distinction between the Ca(2+) current cooperativity, defined by the relationship between exocytosis rate and the whole-terminal Ca(2+) current magnitude, and the underlying Ca(2+) channel cooperativity, defined as the average number of channels involved in the release of a single vesicle. We find simple algebraic expressions that show that the two are different but linearly related. Further, we use three-dimensional computational modeling of buffered Ca(2+) diffusion to analyze these distinct Ca(2+) cooperativity measures, and demonstrate the role of endogenous Ca(2+) buffers on such measures. We show that buffers can either increase or decrease the Ca(2+) current cooperativity of exocytosis, depending on their concentration and the single-channel Ca(2+) current.

  20. CA 125 in ovarian cancer

    NARCIS (Netherlands)

    van der Burg, M. E.; Lammes, F. B.; Verweij, J.

    1992-01-01

    The serum tumour marker CA 125 is useful in the management of ovarian cancer, although it has its limitations. Approximately 85% of the ovarian cancer patients have an increased serum CA 125 at the start of treatment. There is a good correlation between the course of CA 125 and the clinical response

  1. Accessing the nuclear symmetry energy in Ca+Ca collisions

    Directory of Open Access Journals (Sweden)

    Chbihi A.

    2012-07-01

    Full Text Available The status of the analysis of the INDRA-VAMOS experiement performed at GANIL, using the reactions 40,48Ca+40,48Ca reactions at 35AMeV, are presented. Isotopic distributions of fragments produced in multifragmentation events provide information on the importance of the surface term contribution in the symmetry energy by comparison to AMD predictions.

  2. Rates for some reactions involving 42Ca and 44Ca

    International Nuclear Information System (INIS)

    Cheng, C.W.; King, J.D.

    1980-01-01

    Ground-state reaction rates have been deduced from recent cross section measurements for the 42 CA(α, n) 45 Ti, 42 Ca(p, γ) 43 Sc, and 44 Ca(p, n) 44 Sc reactions. Comparison of these rates with those calculated from a statistical model of nuclear reactions. (Woosley et al) shows good agreement for the first two, but the 44 Ca(p, n) rate is more than a factor of 2 less than the theoretical prediction. Stellar reaction rates have been derived from the ground-state rates by multiplying the ground-state rates by the ratio of stellar to ground-state rates given by the statistical model. Both ground-state and stellar rates have been represented by analytic functions of the temperature. The role of these reactions in the approach to quasi-equilibrium during explosive silicon burning is discussed

  3. Sonoma County, CA, 2013 Lidar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sonoma County Vegetation Mapping and LiDAR Consortium retained WSI to provide lidar and Orthophoto data and derived products in Sonoma County, CA. A classified LAS...

  4. Effects of Ca antagonists on Ca fluxes in resistance vessels

    International Nuclear Information System (INIS)

    Cauvin, C.; Saida, K.; van Breemen, C.

    1982-01-01

    Researchers have examined contractions and 45 Ca fluxes induced by norepinephrine (NE) and 80 mM potassium (high K) depolarization and their inhibition by dilitazem in rabbit mesenteric resistance vessels. Contraction induced by both NE and high K depended almost completely on extracellular Ca. Dose-response curves for diltiazem inhibition of NE (10(-5) M) and high K contractions showed ED50 values of 1 X 10(-8) and 6 X 10(-7) M, respectively, indicating that the receptor-operated channel (ROC) was more sensitive than the potential-operated channel (POC) to the action of diltiazem. Diltiazem (10(-6) M) was shown to inhibit NE- and 80 mM K-stimulated 45 Ca influx effectively by 87 +/- 15 and 85 +/- 10%, respectively. Comparison of these data to those obtained from aorta suggest that although the sensitivity of the POC is approximately the same in aorta and mesenteric resistance vessels, the sensitivity of the ROC is much greater in the latter. This increased sensitivity is paralleled by a greatly decreased role of intracellular Ca release in NE contraction in mesenteric resistance vessels

  5. CA125 in ovarian cancer

    DEFF Research Database (Denmark)

    Duffy, M J; Bonfrer, J M; Kulpa, J

    2005-01-01

    value in the detection of early ovarian cancer. At present, therefore, CA125, either alone or in combination with other modalities, cannot be recommended for screening for ovarian cancer in asymptomatic women outside the context of a randomized controlled trial. Preoperative levels in postmenopausal...

  6. Control of ciliary motility by Ca2+: Integration of Ca2+-dependent functions and targets for Ca2+ action

    International Nuclear Information System (INIS)

    Evans, T.C.

    1988-01-01

    To identify functions that regulate Ca 2+ -induced ciliary reversal in Paramecium, mutants defective in terminating depolarization-induced backward swimming were selected. Six independent recessive mutations (k-shy) comprising two complementation groups, k-shyA and k-shyB, were identified. All mutants exhibited prolonged backward swimming in depolarizing solutions. Voltage clamp studies revealed that mutant Ca 2+ current amplitudes were reduced, but could be restored to wild type levels by EGTA injection. The recovery of the mutant Ca 2+ current from Ca 2+ -dependent inactivation, and the decay of the Ca 2+ -dependent K + and Ca 2+ -dependent Na + currents after depolarization were slow in k-shy compared to wild type. To identify protein targets of Ca 2+ action, ciliary proteins that interact with calmodulin (CaM) were characterized. With a 125 I-CaM blot assay, several CaM-binding proteins were identified including axonemal, soluble, and membrane-bound polypeptides. Competitive displacement studies with unlabeled Paramecium CaM, bovine CaM, and troponinC suggested that both protein types bind CaM with high affinity and specificity. To examine the presence of CaM-binding sites in intact axonemes, a filtration binding assay was developed

  7. Ca isotopic fractionation patterns in forest ecosystems

    Science.gov (United States)

    Kurtz, A. C.; Takagi, K.

    2012-12-01

    Calcium stable isotope ratios are an emerging tracer of the biogeochemical cycle of Ca that are just beginning to see significant application to forest ecosystems. The primary source of isotopic fractionation in these systems is discrimination against light Ca during uptake by plant roots. Cycling of vegetation-fractionated Ca establishes isotopically distinct Ca pools within a forest ecosystem. In some systems, the shallow soil exchangeable Ca pool is isotopically heavy relative to Ca inputs. This has been explained by preferential removal of light Ca from the soil. In other systems, the soil exchange pool is isotopically light relative to inputs, which is explained by recycling of plant-fractionated light Ca back into soil. Thus vegetation uptake of light Ca has been called on to account for both isotopically heavy and light Ca in the shallow soil exchange pools. We interpret patterns in ecosystem δ44Ca with the aid of a simple box model of the forest Ca cycle. We suggest that the δ44Ca of exchangeable Ca in the shallow soil pool primarily reflects the relative magnitude of three key fluxes in a forest Ca cycle, 1) the flux of external Ca into the system via weathering or atmospheric deposition, 2) the uptake flux of Ca from soils into the vegetation pool, and 3) the return flux of Ca to shallow soils via remineralization of leaf litter. Two observations that emerge from our model may aid in the application of Ca isotopes to provide insight into the forest Ca cycle. First, regardless of the magnitude of both vegetation Ca uptake and isotopic fractionation, the δ44Ca of the soil exchange pool will equal the input δ44Ca unless the plant uptake and remineralization fluxes are out of balance. A second observation is that the degree to which the shallow soil exchange pool δ44Ca can differ from the input ratio is controlled by the relative rates of biological uptake and external Ca input. Significant differences between soil exchange and input δ44Ca are seen only

  8. A simple method for the accurate determination of free [Ca] in Ca-EGTA solutions.

    Science.gov (United States)

    Bers, D M

    1982-05-01

    A simple method for the accurate determination of free [Ca] in ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid (EGTA)-buffered Ca solutions is described. This method is useful for calibration of Ca macro- and microelectrodes to low free [Ca] and should improve the reliability of calculated free [Ca] in more complex solutions. Briefly, free [Ca] in Ca-EGTA solutions is measured with a Ca electrode, bound Ca is calculated, and Scatchard and double-reciprocal plots are resolved for the total [EGTA] and the apparent Ca-EGTA association constant (K'Ca) in the solutions used. The free [Ca] is then recalculated using the determined parameters, giving a more accurate knowledge of the free [Ca] in these solutions and providing an accurate calibration curve for the Ca electrode. These solutions can then be used to calibrate other Ca electrodes (e.g., Ca microelectrodes) or the calibrated Ca electrode can be used to measure free [Ca] in solutions containing multiple metal ligands. This method allows determination of free [Ca], K'Ca, and total [EGTA] in the actual solutions used regardless of pH, temperature, or ionic strength. It does not require accurate knowledge of K'Ca or EGTA purity and circumvents many potential errors due to assumption of binding parameters. K'Ca was found to be 2.45 +/- 0.04 X 10(6) M-1 in 100 mM KCl, 10 mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid, and 1 mM EGTA at pH 7.00 and 23 degrees C. Total [EGTA] varied with supplier but was always less than quoted.

  9. Distinct Roles for Dorsal CA3 and CA1 in Memory for Sequential Nonspatial Events

    Science.gov (United States)

    Farovik, Anja; Dupont, Laura M.; Eichenbaum, Howard

    2010-01-01

    Previous studies have suggested that dorsal hippocampal areas CA3 and CA1 are both involved in representing sequences of events that compose unique episodes. However, it is uncertain whether the contribution of CA3 is restricted to spatial information, and it is unclear whether CA1 encodes order per se or contributes by an active maintenance of…

  10. 46 CFR 7.130 - Point Conception, CA to Point Sur, CA.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Point Conception, CA to Point Sur, CA. 7.130 Section 7.130 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Pacific Coast § 7.130 Point Conception, CA to Point Sur, CA. (a) A line drawn from the...

  11. 46 CFR 7.125 - Point Vincente, CA to Point Conception, CA.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Point Vincente, CA to Point Conception, CA. 7.125 Section 7.125 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Pacific Coast § 7.125 Point Vincente, CA to Point Conception, CA. (a) A line drawn from...

  12. Multiple Ca2+ sensors in secretion

    DEFF Research Database (Denmark)

    Walter, Alexander M; Groffen, Alexander J; Sørensen, Jakob Balslev

    2011-01-01

    Regulated neurotransmitter secretion depends on Ca(2+) sensors, C2 domain proteins that associate with phospholipids and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) complexes to trigger release upon Ca(2+) binding. Ca(2+) sensors are thought to prevent spontaneous...... fusion at rest (clamping) and to promote fusion upon Ca(2+) activation. At least eight, often coexpressed, Ca(2+) sensors have been identified in mammals. Accumulating evidence suggests that multiple Ca(2+) sensors interact, rather than work autonomously, to produce the complex secretory response...... observed in neurons and secretory cells. In this review, we present several working models to describe how different sensors might be arranged to mediate synchronous, asynchronous and spontaneous neurotransmitter release. We discuss the scenario that different Ca(2+) sensors typically act on one shared...

  13. Direct mobilisation of lysosomal Ca2+ triggers complex Ca2+ signals.

    Science.gov (United States)

    Kilpatrick, Bethan S; Eden, Emily R; Schapira, Anthony H; Futter, Clare E; Patel, Sandip

    2013-01-01

    Accumulating evidence implicates acidic organelles of the endolysosomal system as mobilisable stores of Ca(2+) but their relationship to the better-characterised endoplasmic reticulum (ER) Ca(2+) store remains unclear. Here we show that rapid osmotic permeabilisation of lysosomes evokes prolonged, spatiotemporally complex Ca(2+) signals in primary cultured human fibroblasts. These Ca(2+) signals comprised an initial response that correlated with lysosomal disruption and secondary long-lasting spatially heterogeneous Ca(2+) oscillations that required ER-localised inositol trisphosphate receptors. Electron microscopy identified extensive membrane contact sites between lysosomes and the ER. Mobilisation of lysosomal Ca(2+) stores is thus sufficient to evoke ER-dependent Ca(2+) release probably through lysosome-ER membrane contact sites, and akin to the proposed mechanism of action of the Ca(2+) mobilising messenger nicotinic acid adenine dinucleotide phosphate (NAADP). Our data identify functional and physical association of discrete Ca(2+) stores important for the genesis of Ca(2+) signal complexity.

  14. Ca2+/cation antiporters (CaCA: Identification, characterization and expression profiling in bread wheat (Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Mehak Taneja

    2016-11-01

    Full Text Available The Ca2+/cation antiporters (CaCA superfamily proteins play vital function in Ca2+ ion homeostasis, which is an important event during development and defense response. Molecular characterization of these proteins has been performed in certain plants, but they are still not characterized in Triticum aestivum (bread wheat. Herein, we identified thirty four TaCaCA superfamily proteins, which were classified into TaCAX, TaCCX, TaNCL and TaMHX protein families based on their structural organization and evolutionary relation with earlier reported proteins. Since the T. aestivum comprises an allohexaploid genome, TaCaCA genes were derived from each A, B and D subgenome and homeologous chromosome (HC, except chromosome-group 1. Majority of genes were derived from more than one HCs in each family that were considered as homeologous genes (HGs due to their high similarity with each other. These HGs showed comparable gene and protein structures in terms of exon/intron organization and domain architecture. Majority of TaCaCA proteins comprised two Na_Ca_ex domains. However, TaNCLs consisted of an additional EF-hand domain with calcium binding motifs. Each TaCaCA protein family consisted of about ten transmembrane and two α-repeat regions with specifically conserved signature motifs except TaNCL, which had single α-repeat. Variable expression of most of the TaCaCA genes during various developmental stages suggested their specified role in development. However, constitutively high expression of a few genes like TaCAX1-A and TaNCL1-B indicated their role throughout the plant growth and development. The modulated expression of certain genes during biotic (fungal infections and abiotic stresses (heat, drought, salt suggested their role in stress response. Majority of TaCCX and TaNCL family genes were found highly affected during various abiotic stresses. However the role of individual gene needs to be established. The present study unfolded the opportunity

  15. Ca2+/Cation Antiporters (CaCA): Identification, Characterization and Expression Profiling in Bread Wheat (Triticum aestivum L.).

    Science.gov (United States)

    Taneja, Mehak; Tyagi, Shivi; Sharma, Shailesh; Upadhyay, Santosh Kumar

    2016-01-01

    The Ca 2+ /cation antiporters (CaCA) superfamily proteins play vital function in Ca 2+ ion homeostasis, which is an important event during development and defense response. Molecular characterization of these proteins has been performed in certain plants, but they are still not characterized in Triticum aestivum (bread wheat). Herein, we identified 34 TaCaCA superfamily proteins, which were classified into TaCAX, TaCCX, TaNCL, and TaMHX protein families based on their structural organization and evolutionary relation with earlier reported proteins. Since the T. aestivum comprises an allohexaploid genome, TaCaCA genes were derived from each A, B, and D subgenome and homeologous chromosome (HC), except chromosome-group 1. Majority of genes were derived from more than one HCs in each family that were considered as homeologous genes (HGs) due to their high similarity with each other. These HGs showed comparable gene and protein structures in terms of exon/intron organization and domain architecture. Majority of TaCaCA proteins comprised two Na_Ca_ex domains. However, TaNCLs consisted of an additional EF-hand domain with calcium binding motifs. Each TaCaCA protein family consisted of about 10 transmembrane and two α-repeat regions with specifically conserved signature motifs except TaNCL, which had single α-repeat. Variable expression of most of the TaCaCA genes during various developmental stages suggested their specified role in development. However, constitutively high expression of a few genes like TaCAX1-A and TaNCL1-B indicated their role throughout the plant growth and development. The modulated expression of certain genes during biotic (fungal infections) and abiotic stresses (heat, drought, salt) suggested their role in stress response. Majority of TaCCX and TaNCL family genes were found highly affected during various abiotic stresses. However, the role of individual gene needs to be established. The present study unfolded the opportunity for detail

  16. Weak transition of 44Ca

    International Nuclear Information System (INIS)

    Tauhata, L.

    1971-01-01

    A study of the nuclear core contribution to the excited nuclear states was done, along with its theoretical evaluation and interpretation, in the light nuclei region. The 727 KeV gamma ray transition between the 1885 KeV O + and 1157 KeV - 2 + states was detected, putting in evidence experimentally, the possibility of the 0 + state, characterized as core excitation, and found to be by + decay or electron capture from 44,44m Sc. The formation of the 2850 KeV state, due to 880 KeV transition from the 3667 KeV state, is re-discussed. The 564 KeV and 1684 KeV transitions from the 2850 KeV state to the 2285 KeV and 1157 KeV states, respectively, are also discussed. A new scheme is proposed for the 44 Ca excited states. (Author) [pt

  17. Role of Ca2+, membrane excitability, and Ca2+ stores in failing muscle contraction with aging.

    Science.gov (United States)

    Payne, Anthony Michael; Jimenez-Moreno, Ramón; Wang, Zhong-Ming; Messi, María Laura; Delbono, Osvaldo

    2009-04-01

    Excitation-contraction (EC) coupling in a population of skeletal muscle fibers of aged mice becomes dependent on the presence of external Ca(2+) ions (Payne, A.M., Zheng, Z., Gonzalez, E., Wang, Z.M., Messi, M.L., Delbono, O., 2004b. External Ca(2+)-dependent excitation - contraction coupling in a population of aging mouse skeletal muscle fibers. J. Physiol. 560, 137-155.). However, the mechanism(s) underlying this process remain unknown. In this work, we examined the role of (1) extracellular Ca(2+); (2) voltage-induced influx of external Ca(2+) ions; (3) sarcoplasmic reticulum (SR) Ca(2+) depletion during repeated contractions; (4) store-operated Ca(2+) entry (SOCE); (5) SR ultrastructure; (6) SR subdomain localization of the ryanodine receptor; and (7) sarcolemmal excitability in muscle force decline with aging. These experiments show that external Ca(2+), but not Ca(2+) influx, is needed to maintain force upon repetitive fiber electrical stimulation. Decline in fiber force is associated with depressed SR Ca(2+) release. SR Ca(2+) depletion, SOCE, and the putative segregated Ca(2+) release store do not play a significant role in external Ca(2+)-dependent contraction. More importantly, a significant number of action potentials fail in senescent mouse muscle fibers subjected to a stimulation frequency. These results indicate that failure to generate action potentials accounts for decreased intracellular Ca(2+) mobilization and tetanic force in aging muscle exposed to a Ca(2+)-free medium.

  18. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

    Directory of Open Access Journals (Sweden)

    Xiao-Chen Li

    Full Text Available Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+ homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+ current (I(Ca was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca did not compromise the Ca(2+-induced Ca(2+ release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca. Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+ removal were more rapid in ground squirrels. Ca(2+ sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca threshold, low SR Ca(2+ leak and rapid cytosolic Ca(2+ clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+ homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+ overload-related heart diseases.

  19. Lattice Dynamics of fcc Ca

    DEFF Research Database (Denmark)

    Stassis, C.; Zaretsky, J.; Misemer, D. K.;

    1983-01-01

    A large single crystal of FCC Ca was grown and was used to study the lattice dynamics of this divalent metal by coherent inelastic neutron scattering. The phonon dispersion curves were measured, at room temperature, along the [ξ00], [ξξ0], [ξξξ], and [0ξ1] symmetry directions. The dispersion curves...... to the propagation of elastic waves. The frequencies of the T1[ξξ0] branch for ξ between approximately 0.5 and 0.8 are slightly above the velocity-of-sound line determined from the low-frequency measurements. Since a similar effect has been observed in FCC Yb, it is natural to assume that the anomalous dispersion.......8, there is a relative decrease in the electronic screening of the vibrational motion of the nuclei, which may account for the positive dispersion exhibited by the T1 [ξξ0] branch in this range of ξ values. The data were used to evaluate the elastic constants, the phonon density of states, and the lattice specific heat...

  20. Coupled Ca2+/H+ transport by cytoplasmic buffers regulates local Ca2+ and H+ ion signaling.

    Science.gov (United States)

    Swietach, Pawel; Youm, Jae-Boum; Saegusa, Noriko; Leem, Chae-Hun; Spitzer, Kenneth W; Vaughan-Jones, Richard D

    2013-05-28

    Ca(2+) signaling regulates cell function. This is subject to modulation by H(+) ions that are universal end-products of metabolism. Due to slow diffusion and common buffers, changes in cytoplasmic [Ca(2+)] ([Ca(2+)]i) or [H(+)] ([H(+)]i) can become compartmentalized, leading potentially to complex spatial Ca(2+)/H(+) coupling. This was studied by fluorescence imaging of cardiac myocytes. An increase in [H(+)]i, produced by superfusion of acetate (salt of membrane-permeant weak acid), evoked a [Ca(2+)]i rise, independent of sarcolemmal Ca(2+) influx or release from mitochondria, sarcoplasmic reticulum, or acidic stores. Photolytic H(+) uncaging from 2-nitrobenzaldehyde also raised [Ca(2+)]i, and the yield was reduced following inhibition of glycolysis or mitochondrial respiration. H(+) uncaging into buffer mixtures in vitro demonstrated that Ca(2+) unloading from proteins, histidyl dipeptides (HDPs; e.g., carnosine), and ATP can underlie the H(+)-evoked [Ca(2+)]i rise. Raising [H(+)]i tonically at one end of a myocyte evoked a local [Ca(2+)]i rise in the acidic microdomain, which did not dissipate. The result is consistent with uphill Ca(2+) transport into the acidic zone via Ca(2+)/H(+) exchange on diffusible HDPs and ATP molecules, energized by the [H(+)]i gradient. Ca(2+) recruitment to a localized acid microdomain was greatly reduced during intracellular Mg(2+) overload or by ATP depletion, maneuvers that reduce the Ca(2+)-carrying capacity of HDPs. Cytoplasmic HDPs and ATP underlie spatial Ca(2+)/H(+) coupling in the cardiac myocyte by providing ion exchange and transport on common buffer sites. Given the abundance of cellular HDPs and ATP, spatial Ca(2+)/H(+) coupling is likely to be of general importance in cell signaling.

  1. An Aqueous Ca-Ion Battery.

    Science.gov (United States)

    Gheytani, Saman; Liang, Yanliang; Wu, Feilong; Jing, Yan; Dong, Hui; Rao, Karun K; Chi, Xiaowei; Fang, Fang; Yao, Yan

    2017-12-01

    Multivalent-ion batteries are emerging as low-cost, high energy density, and safe alternatives to Li-ion batteries but are challenged by slow cation diffusion in electrode materials due to the high polarization strength of Mg- and Al-ions. In contrast, Ca-ion has a low polarization strength similar to that of Li-ion, therefore a Ca-ion battery will share the advantages while avoiding the kinetics issues related to multivalent batteries. However, there is no battery known that utilizes the Ca-ion chemistry due to the limited success in Ca-ion storage materials. Here, a safe and low-cost aqueous Ca-ion battery based on a highly reversible polyimide anode and a high-potential open framework copper hexacyanoferrate cathode is demonstrated. The prototype cell shows a stable capacity and high efficiency at both high and low current rates, with an 88% capacity retention and an average 99% coloumbic efficiency after cycling at 10C for 1000 cycles. The Ca-ion storage mechanism for both electrodes as well as the origin of the fast kinetics have been investigated. Additional comparison with a Mg-ion cell with identical electrodes reveals clear kinetics advantages for the Ca-ion system, which is explained by the smaller ionic radii and more facile desolvation of hydrated Ca-ions.

  2. Cuento: Sangre de caña

    Directory of Open Access Journals (Sweden)

    Segundo Benjamín Corredor

    1967-09-01

    Full Text Available El viento se convertía en murmullo contra las hojas de los cañaverales y contra los techos semipelados del rancho. También menguaba el calor que maduraba los plantíos de caña y que hacía más efusiva la sangre de los moradores.

  3. By Regulating Mitochondrial Ca2+-Uptake UCP2 Modulates Intracellular Ca2+.

    Directory of Open Access Journals (Sweden)

    Lukas Jaroslaw Motloch

    Full Text Available The possible role of UCP2 in modulating mitochondrial Ca2+-uptake (mCa2+-uptake via the mitochondrial calcium uniporter (MCU is highly controversial.Thus, we analyzed mCa2+-uptake in isolated cardiac mitochondria, MCU single-channel activity in cardiac mitoplasts, dual Ca2+-transients from mitochondrial ((Ca2+m and intracellular compartment ((Ca2+c in the whole-cell configuration in cardiomyocytes of wild-type (WT and UCP2-/- mice.Isolated mitochondria showed a Ru360 sensitive mCa2+-uptake, which was significantly decreased in UCP2-/- (229.4±30.8 FU vs. 146.3±23.4 FU, P0.05 and transsarcolemmal Ca2+-influx was inhibited suggesting a possible compensatory mechanism. Additionally, we observed an inhibitory effect of ATP on mCa2+-uptake in WT mitoplasts and (Ca2+m of cardiomyocytes leading to an increase of (Ca2+c while no ATP dependent effect was observed in UCP2-/-.Our results indicate regulatory effects of UCP2 on mCa2+-uptake. Furthermore, we propose, that previously described inhibitory effects on MCU by ATP may be mediated via UCP2 resulting in changes of excitation contraction coupling.

  4. Impact of seawater [Ca2+] on the calcification and calcite Mg / Ca of Amphistegina lessonii

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; Thoms, S.; Nehrke, G.; Reichart, G. J.; de Nooijer, L. J.; Bijma, J.

    2015-01-01

    Mg / Ca ratios in foraminiferal tests are routinely used as paleotemperature proxies, but on long timescales, they also hold the potential to reconstruct past seawater Mg / Ca. The impact of both temperature and seawater Mg / Ca on Mg incorporation in Foraminifera has been quantified by a number of

  5. Ca-Dependent Folding of Human Calumenin

    Science.gov (United States)

    Mazzorana, Marco; Hussain, Rohanah; Sorensen, Thomas

    2016-01-01

    Human calumenin (hCALU) is a six EF-hand protein belonging to the CREC family. As other members of the family, it is localized in the secretory pathway and regulates the activity of SERCA2a and of the ryanodine receptor in the endoplasmic reticulum (ER). We have studied the effects of Ca2+ binding to the protein and found it to attain a more compact structure upon ion binding. Circular Dichroism (CD) measurements suggest a major rearrangement of the protein secondary structure, which reversibly switches from disordered at low Ca2+ concentrations to predominantly alpha-helical when Ca2+ is added. SAXS experiments confirm the transition from an unfolded to a compact structure, which matches the structural prediction of a trilobal fold. Overall our experiments suggest that calumenin is a Ca2+ sensor, which folds into a compact structure, capable of interacting with its molecular partners, when Ca2+ concentration within the ER reaches the millimolar range. PMID:26991433

  6. CaMKII in the Cardiovascular System: Sensing Redox States

    Science.gov (United States)

    Erickson, Jeffrey R.; He, B. Julie; Grumbach, Isabella M.; Anderson, Mark E

    2013-01-01

    The multifunctional Ca2+ and calmodulin-dependent protein kinase II (CaMKII) is now recognized to play a central role in pathological events in the cardiovascular system. CaMKII has diverse downstream targets that promote vascular disease, heart failure and arrhythmias, so improved understanding of CaMKII signaling has the potential to lead to new therapies for cardiovascular disease. CaMKII is a multimeric serine-threonine kinase that is initially activated by binding calcified calmodulin (Ca2+/CaM). Under conditions of sustained exposure to elevated Ca2+/CaM CaMKII transitions into a Ca2+/CaM-autonomous enzyme by two distinct but parallel processes. Autophosphorylation of threonine 287 in the CaMKII regulatory domain ‘traps’ CaMKII into an open configuration even after Ca2+/CaM unbinding. More recently, our group identified a pair of methionines (281/282) in the CaMKII regulatory domain that undergo a partially reversible oxidation which, like autophosphorylation, prevents CaMKII from inactivating after Ca2+/CaM unbinding. Here we review roles of CaMKII in cardiovascular disease with an eye to understanding how CaMKII may act as a transduction signal to connect pro-oxidant conditions into specific downstream pathological effects that are relevant to rare and common forms of cardiovascular disease. PMID:21742790

  7. Sporadic Ca and Ca+ layers at mid-latitudes: Simultaneous observations and implications for their formation

    Directory of Open Access Journals (Sweden)

    M. Gerding

    2001-01-01

    Full Text Available We report on the observations of 188 sporadic layers of either Ca atoms and/or Ca ions that we have observed during 112 nights of lidar soundings of Ca, and 58 nights of Ca+ soundings, at Kühlungsborn, Germany (54° N, 12° E. The Ca+ soundings have been performed simultaneously and in a common volume with the Ca soundings by two separate lidars. Correlations between sporadic neutral and ionized metal layers are demonstrated through four case studies. A systematic study of the variations of occurrence of sporadic Ca and Ca+ layers reveals that neutral and ionized Ca layers are not as closely correlated as expected earlier: (a The altitude distribution shows the simultaneous occurrence of both sporadic Ca and Ca+ layers to be most likely only in the narrow altitude range between 90 and 95 km. Above that region, in the lower thermosphere, the sporadic ion layers are much more frequent than atom layers. Below 90 km only very few sporadic layers have been observed; (b The seasonal variation of sporadic Ca layers exhibits a minimum of occurrence in summer, while sporadic Ca+ layers do not show a significant seasonal variation (only the dense Ca+ layers appear to have a maximum in summer. At mid-latitudes sporadic Ca layers are more frequent than sporadic layers of other atmospheric metals like Na or K. For the explanation of our observations new formation mechanisms are discussed.Key words. Ionosphere (ion chemistry and composition; ionosphere-atmosphere interactions; mid-latitude ionosphere

  8. Results of measuring internal Ca absorption and Ca kinetics with /sup 47/Ca in patients suffering from chronically recurrent urolithiasis

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, L.; Esther, G.; Serfling, D.; Bast, R. (Rostock Univ. (German Democratic Republic). Radiologische Klinik)

    1983-07-01

    47 patients with chronically recurrent calcium lithiasis (with between 3 and over 100 stone episodes) and an average age of 43.2 years have been examined. The Ca absorption lay between 42.7% and 90.0% of the dose, the average was 59.3% with a standard deviation of +- 12.9. This is higher than in persons with healthy kidneys. The Ca absorption is significantly lower in patients with renal insufficiency. Studies on Ca kinetics revealed turnover rates and pool sizes within the normal range.

  9. Results of measuring enteral Ca absorption and Ca kinetics with 47Ca in patients suffering from chronically recurrent urolithiasis

    International Nuclear Information System (INIS)

    Hoffmann, L.; Esther, G.; Serfling, D.; Bast, R.

    1983-01-01

    47 patients with chronically recurrent calcium lithiasis (with between 3 and over 100 stone episodes) and an average age of 43.2 years have been examined. The Ca absorption lay between 42.7% and 90.0% of the dose, the average was 59.3% with a standard deviation of +- 12.9. This is higher than in persons with healthy kidneys. The Ca absorption is significantly lower in patients with renal insufficiency. Studies on Ca kinetics revealed turnover rates and pool sizes within the normal range. (author)

  10. Ca2+-dependent structural rearrangements within Na+–Ca2+ exchanger dimers

    OpenAIRE

    John, Scott A.; Ribalet, Bernard; Weiss, James N.; Philipson, Kenneth D.; Ottolia, Michela

    2011-01-01

    Cytoplasmic Ca2+ is known to regulate Na+–Ca2+ exchanger (NCX) activity by binding to two adjacent Ca2+-binding domains (CBD1 and CBD2) located in the large intracellular loop between transmembrane segments 5 and 6. We investigated Ca2+-dependent movements as changes in FRET between exchanger proteins tagged with CFP or YFP at position 266 within the large cytoplasmic loop. Data indicate that the exchanger assembles as a dimer in the plasma membrane. Addition of Ca2+ decreases the distance be...

  11. Isospin effects in {sup 40,48}Ca+{sup 40,48}Ca collisions

    Energy Technology Data Exchange (ETDEWEB)

    Henzl, V., E-mail: henzl@mit.ed [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Henzlova, D.; Kilburn, M. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Verde, G. [INFN, Sezione di Catania. 64 Via S. Sofia, I-95123, Catania (Italy); Brown, D. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Chbihi, A. [GANIL, CEA et IN2P3-CNRS, B.P. 5027, F-14076 Caen Cedex (France); Coupland, D. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Elson, J. [Departments of Chemistry and Physics, Washington University, St. Louis, MO 63130 (United States); Famiano, M. [Western Michigan University, 2229 Everett Tower, Kalamazoo, MI 49008-5252 (United States); Herlitzius, C. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Hudan, S. [Indiana Univ. Cyclotron Facility, 2401 Milo B. Sampson Lane, Bloomington, IN 47405-4001 (United States); Lee, J.; Lukyanov, S.; Lynch, W.; Rogers, A.; Sanetullaev, A. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States); Sobotka, L. [Departments of Chemistry and Physics, Washington University, St. Louis, MO 63130 (United States); Souza, R.T. de [Indiana Univ. Cyclotron Facility, 2401 Milo B. Sampson Lane, Bloomington, IN 47405-4001 (United States); Sun, Z.Y.; Tsang, B. [MSU-NSCL, 1 Cyclotron, East Lansing MI, 48824 (United States)

    2010-03-01

    The isospin dependence of two proton correlations is studied in {sup 40}Ca+{sup 40}Ca and {sup 48}Ca+{sup 48}Ca collisions at E/A=80MeV. Measurements were performed with the HiRA detector array complemented by the 4pi Ball at NSCL. We observe a strong isospin dependence of the pp-correlation functions; however the emitting source radius extracted using the imaging technique yields no sensitivity to the isospin of the reaction system. We interpret this result as a consequence of smaller fraction of fast proton emission in the neutron rich {sup 48}Ca system.

  12. Isospin effects in 40,48Ca+40,48Ca collisions

    International Nuclear Information System (INIS)

    Henzl, V.; Henzlova, D.; Kilburn, M.; Verde, G.; Brown, D.; Chbihi, A.; Coupland, D.; Elson, J.; Famiano, M.; Herlitzius, C.; Hudan, S.; Lee, J.; Lukyanov, S.; Lynch, W.; Rogers, A.; Sanetullaev, A.; Sobotka, L.; Souza, R.T. de; Sun, Z.Y.; Tsang, B.

    2010-01-01

    The isospin dependence of two proton correlations is studied in 40 Ca+ 40 Ca and 48 Ca+ 48 Ca collisions at E/A=80MeV. Measurements were performed with the HiRA detector array complemented by the 4π Ball at NSCL. We observe a strong isospin dependence of the pp-correlation functions; however the emitting source radius extracted using the imaging technique yields no sensitivity to the isospin of the reaction system. We interpret this result as a consequence of smaller fraction of fast proton emission in the neutron rich 48 Ca system.

  13. PGC-1α accelerates cytosolic Ca2+ clearance without disturbing Ca2+ homeostasis in cardiac myocytes

    International Nuclear Information System (INIS)

    Chen, Min; Wang, Yanru; Qu, Aijuan

    2010-01-01

    Energy metabolism and Ca 2+ handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1α in cardiac Ca 2+ signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1α via adenoviral transduction. Our data shows that overexpressing PGC-1α improved myocyte contractility without increasing the amplitude of Ca 2+ transients, suggesting that myofilament sensitivity to Ca 2+ increased. Interestingly, the decay kinetics of global Ca 2+ transients and Ca 2+ waves accelerated in PGC-1α-expressing cells, but the decay rate of caffeine-elicited Ca 2+ transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca 2+ -ATPase (SERCA2a), but not Na + /Ca 2+ exchange (NCX) contribute to PGC-1α-induced cytosolic Ca 2+ clearance. Furthermore, PGC-1α induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1α did not disturb cardiac Ca 2+ homeostasis, because SR Ca 2+ load and the propensity for Ca 2+ waves remained unchanged. These data suggest that PGC-1α can ameliorate cardiac Ca 2+ cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1α-calcium handing pathway sheds new light on the role of PGC-1α in the therapy of cardiac diseases.

  14. Evaluation of Serum CEA, CA19-9, CA72-4, CA125 and Ferritin as Diagnostic Markers and Factors of Clinical Parameters for Colorectal Cancer.

    Science.gov (United States)

    Gao, Yanfeng; Wang, Jinping; Zhou, Yue; Sheng, Sen; Qian, Steven Y; Huo, Xiongwei

    2018-02-09

    Blood-based protein biomarkers have recently shown as simpler diagnostic modalities for colorectal cancer, while their association with clinical pathological characteristics is largely unknown. In this study, we not only examined the sensitivity and reliability of single/multiple serum markers for diagnosis, but also assessed their connection with pathological parameters from a total of 279 colorectal cancer patients. Our study shown that glycoprotein carcinoembryonic antigen (CEA) owns the highest sensitivity among single marker in the order of CEA > cancer antigen 72-4 (CA72-4) > cancer antigen 19-9 9 (CA19-9) > ferritin > cancer antigen 125 (CA125), while the most sensitive combined-markers for two to five were: CEA + CA72-4; CEA + CA72-4 + CA125; CEA + CA19-9 + CA72-4 + CA125; and CEA + CA19-9 + CA72-4 + CA125 + ferritin, respectively. We also demonstrated that patients who had positive preoperative serum CEA, CA19-9, or CA72-4 were more likely with lymph node invasion, positive CA125 were prone to have vascular invasion, and positive CEA or CA125 were correlated with perineural invasion. In addition, positive CA19-9, CA72-4, or CA125 was associated with poorly differentiated tumor, while CEA, CA19-9, CA72-4, CA125 levels were positively correlated with pathological tumor-node-metastasis stages. We here conclude that combined serum markers can be used to not only diagnose colorectal cancer, but also appraise the tumor status for guiding treatment, evaluation of curative effect, and prognosis of patients.

  15. Regulated release of Ca2+ from respiring mitochondria by Ca2+/2H+ antiport.

    Science.gov (United States)

    Fiskum, G; Lehninger, A L

    1979-07-25

    Simultaneous measurements of oxygen consumption and transmembrane transport of Ca2+, H+, and phosphate show that the efflux of Ca2+ from respiring tightly coupled rat liver mitochondria takes place by an electroneutral Ca2+/2H+ antiport process that is ruthenium red-insensitive and that is regulated by the oxidation-reduction state of the mitochondrial pyridine nucleotides. When mitochondrial pyridine nucleotides are kept in a reduced steady state, the efflux of Ca2+ is inhibited; when they are in an oxidized state, Ca2+ efflux is activated. These processes were demonstrated by allowing phosphate-depleted mitochondria respiring on succinate in the presence of rotenone to take up Ca2+ from the medium. Upon subsequent addition of ruthenium red to block Ca2+ transport via the electrophoretic influx pathway, and acetoacetate, to bring mitochondrial pyridine nucleotides into the oxidized state, Ca2+ efflux and H+ influx ensued. The observed H+ influx/Ca2+ efflux ratio was close to the value 2.0 predicted for the operation of an electrically neutral Ca2+/2H+ antiport process.

  16. Reduced endogenous Ca2+ buffering speeds active zone Ca2+ signaling.

    Science.gov (United States)

    Delvendahl, Igor; Jablonski, Lukasz; Baade, Carolin; Matveev, Victor; Neher, Erwin; Hallermann, Stefan

    2015-06-09

    Fast synchronous neurotransmitter release at the presynaptic active zone is triggered by local Ca(2+) signals, which are confined in their spatiotemporal extent by endogenous Ca(2+) buffers. However, it remains elusive how rapid and reliable Ca(2+) signaling can be sustained during repetitive release. Here, we established quantitative two-photon Ca(2+) imaging in cerebellar mossy fiber boutons, which fire at exceptionally high rates. We show that endogenous fixed buffers have a surprisingly low Ca(2+)-binding ratio (∼ 15) and low affinity, whereas mobile buffers have high affinity. Experimentally constrained modeling revealed that the low endogenous buffering promotes fast clearance of Ca(2+) from the active zone during repetitive firing. Measuring Ca(2+) signals at different distances from active zones with ultra-high-resolution confirmed our model predictions. Our results lead to the concept that reduced Ca(2+) buffering enables fast active zone Ca(2+) signaling, suggesting that the strength of endogenous Ca(2+) buffering limits the rate of synchronous synaptic transmission.

  17. High CA-125 and CA19-9 levels in spontaneous ruptured ovarian endometriomas.

    Science.gov (United States)

    Dai, Xinyue; Jin, Chu; Hu, Yan; Zhang, Qian; Yan, Xiaojian; Zhu, Fangfang; Lin, Feng

    2015-10-23

    To evaluate the clinical significance of serum CA-125 and CA19-9 in women with spontaneous ruptured ovarian endometriomas. From January 2006 to April 2015, a total of 1653 women were diagnosed with ovarian endometriomas, and 43 women were diagnosed with the spontaneous rupture of their ovarian endometrioma. In addition, 70 women diagnosed with unruptured ovarian endometriomas were chosen to serve as control subjects. Serum CA-125 and CA19-9 levels, together with the clinical materials, were collected. Serum CA-125, CA19-9, and the combined biomarkers were shown to be obviously elevated in the spontaneous ruptured ovarian endometrioma group (p=0.001, p=0.001, p=0.001, respectively). The AUC value for the combined biomarkers was 0.992 (95% CI, 0.981-1.000), with a high sensitivity and specificity of nearly 100% and 93.6%, respectively. Moreover, the maximum diameter of the mass was significantly (p=0.001) increased in the ruptured group. Serum CA-125 and CA19-9 were significantly increased in patients with spontaneous ruptured ovarian endometriomas. Moreover, the combined biomarkers were better than either CA-125 or CA19-9 alone in the diagnosis of a spontaneous rupture of the ovarian endometrioma. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. EnviroAtlas - Fresno, CA - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Fresno, CA EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  19. Role of Ca++ in Shoot Gravitropism. [avena

    Science.gov (United States)

    Rayle, D. L.

    1985-01-01

    A cornerstone in the argument that Ca(2+) levels may regulate growth is the finding the EGTA promotes straight growth. The usual explanation for these results is that Ca(2+) chelation from cell walls results in wall loosening and thus accelerated straight growth. The ability of frozen-thawed Avena coleoptile tissue (subjected to 15g tension) to extend in response to EGTA and Quin II was examined. The EGTA when applied in weakly buffered (i.e., 0.1mM) neutral solutions initiates rapid extension. When the buffer strength is increased, similar concentrations of EGTA produce no growth response. This implies when EGTA liberated protons are released upon Ca(2+) chelation they can either initiate acid growth (low buffer conditions) or if consumed (high buffer conditions) have no effect. Thus Ca(2+) chelation in itself apparently does not result in straight growth.

  20. YouthCaN 2001 / Sirje Janikson

    Index Scriptorium Estoniae

    Janikson, Sirje

    2001-01-01

    Aprillis 2001 toimus keskkonnateemaline õpilaskonverents YouthCaN 2001 Ameerika Loodusajaloo Muuseumis New Yorkìs. 35 seminarist ühe viis läbi Tartu Noorte Loodusmaja geoloogia ja keskkonnaringi esindus, tutvustati loodusmaja keskkonnaprojekte ja räägiti keskkonnaalaste veebilehtede koostamise kogemustest. YouthCaN (Youth Communicating and Networking) on rahvusvaheline noorte organisatsioon, mis vahendab kogemusi ja uusi ideid elukeskkonnast huvitatud noorte hulgas

  1. [Association of ovarian tumors with CA-125].

    Science.gov (United States)

    Martínez-Acosta, Judith Elena; Olguín-Cruces, Víctor Alberto

    2016-01-01

    The tumor marker CA-125 is the most widely used serum marker for ovarian cancer screening. The aim of this paper was to establish the association between histopathologic result of ovarian tumors with serologic CA-125 and utility for the diagnosis of ovarian tumors at a Ginecoobstetric hospital. An observational, retrospective, descriptive and longitudinal study, from September 1st 2010 to February 28 2013. All patients with histopathologic report ovarian tumor and CA-125 was selected to analyze the association of ovarian tumors with their histological type, biological behavior, range positivity of CA-125 and its relationship to the pre and postmenopausal state. Of 1213 patients, 334 were included. Utility of CA-125 in postmenopausal reported positive predictive value of 67.5%, with sensitivity (72%), specificity (82.6%) and negative predictive value (86.1%), both with p = 0.001, mainly in the epithelial origin. In premenopausal a low positive predictive value was reported. The CA-125 is useful for screening for ovarian cancer in postmenopausal women, mainly for epithelial origin.

  2. Preparation and characterization of Eu 3 activated CaSiO3,(CaA ...

    Indian Academy of Sciences (India)

    Eu3+ activated CaSiO3, (Ca, Ba) SiO3 and (Ca, Sr) SiO3 have been prepared by sol–gel technique. Residual solvent and organic contents in the gel were removed by firing at 100°C for 3–4 h at 300 and 600°C for 2 h. Small exothermic shoulder around 850 to 875°C, as observed in DTA curve, corresponds to crystallization ...

  3. Ca(2+-dependent regulation of the Ca(2+ concentration in the myometrium mitochondria. II. Ca(2+ effects on mitochondria membranes polarization and [Ca(2+](m

    Directory of Open Access Journals (Sweden)

    L. G. Babich

    2017-06-01

    Full Text Available It is known that Ca2+ accumulation in the mitochondria undergoes complex regulation by Ca2+ itself. But the mechanisms of such regulation are still discussed. In this paper we have shown that Ca ions directly or indirectly regulate the level of myometrium mitochondria membranes polarization. The additions of 100 µM Ca2+ were accompanied by depolarization of the mitochondria membranes. The following experiments were designed to study the impact of Ca2+ on the myometrium mitochondria [Ca2+]m. Isolated myometrium mitochondria were preincubated without or with 10 μM Са2+ followed by 100 μM Са2+ addition. Experiments were conducted in three mediums: without ATP and Mg2+ (0-medium, in the presence of 3 mM Mg2+ (Mg-medium and 3 mM Mg2+ + 3 mM ATP (Mg,ATP-medium. It was shown that the effects of 10 μM Са2+ addition were different in different mediums, namely in 0- and Mg-medium the [Ca2+]m values increased, whereas in Mg,ATP-medium statistically reliable changes were not registered. Preincubation of mitochondria with 10 μM Са2+ did not affect the [Ca2+]m value after the addition of 100 μM Са2+. The [Ca2+]m values after 100 μM Са2+ addition were the same in 0- and Mg,ATP-mediums and somewhat lower in Mg-medium. Preliminary incubation of mitochondria with 10 μM Са2+ in 0- and Mg-mediums reduced changes of Fluo 4 normalized fluorescence values that were induced by 100 μM Са2+ additions, but in Mg,ATP-medium such differences were not recorded. It is concluded that Са2+ exchange in myometrium mitochondria is regulated by the concentration of Ca ions as in the external medium, so in the matrix of mitochondria. The medium composition had a significant impact on the [Са2+]m values in the absence of exogenous cation. It is suggested that light increase of [Са2+]m before the addition of 100 μM Са2+ may have a positive effect on the functional activity of the mitochondria.

  4. Mg/Ca of Continental Ostracode Shells

    Science.gov (United States)

    Ito, E.; Forester, R. M.; Marco-Barba, J.; Mezquita, F.

    2007-12-01

    Marine ionic chemistry is thought to remain constant. This, together with the belief that marine calcifiers partition Mg/Ca in a systematic manner as functions of temperature (and Mg/Ca) of water forms the basis of the Mg/Ca thermometer. In continental settings both of these assumptions are usually not true. Continental waters contain a wide variety of solutes in absolute and relative ion concentrations. Hence, waters with identical Mg/Ca may have very different concentrations of Mg and Ca and very different anions. Here we use two examples to focus on the effects of ion chemistry on Mg/Ca partitioning in continental ostracode shells and we ignore the complexities of solute evolution, which can change Mg/Ca over timescales of minutes to millennia. Palacios-Fest and Dettman (2001) conducted a monthly study of ,Cypridopsis vidua at El Yeso Lake in Sonora, Mexico. They established a relation between temperature and average shell Mg/Ca using regression analyses on averaged data. When their Mg/Ca-temperature relation is applied to monthly ,C. vidua data from Page Pond near Cleveland, Ohio, water temperatures of -8 to -1°C are obtained. The observed Mg/Ca ranges for El Yeso Lake (0.31 to 0.46) and Page Pond (0.33 to 0.46) are similar, as are their specific conductivities (700 to 850μS for El Yeso Lake; 400 to 600μS for Page Pond). However, [Ca] is 140-260 mg/L for El Yeso, but only 70-90 mg/L for Page Pond. Page Pond data, in fact, shows a good temperature shell Mg/Ca relation for .C. vidua, but the relation is different from that at El Yeso. Hence, shell Mg/Ca is a multi-valued, family of curves function of temperature and Mg/Ca of water that depends on the [Mg] and [Ca] values in water and perhaps other factors. Our second example comes from sites near Valencia, Spain and involves shell data for ,Cyprideis torosa, an estuarine ostracode that is tolerant of a wide range of salinity and can live in continental waters as long as the carbonate alkalinity to Ca ratio is

  5. Electronic structures and magnetism of CaFeAsH and CaFeAsF

    International Nuclear Information System (INIS)

    Wang Guangtao; Shi Xianbiao; Liu Haipeng; Liu Qingbo

    2015-01-01

    We studied the electronic structures, magnetism, and Fermi surface (FS) nesting of CaFeAsH and CaFeAsF by first-principles calculations. In the nonmagnetic (NM) states, we found strong FS nesting, which induces magnetic instability and a spin density wave (SDW). Our calculations indicate that the ground state of CaFeAsH and CaFeAsF is the stripe antiferromagnetic state. The calculated bare susceptibility χ 0 (q) peaked at the M-point and was clearly suppressed and became slightly incommensurate with both electron doping and hole doping for both materials. (author)

  6. Effect of Ca content on equilibrium Ca isotope fractionation between orthopyroxene and clinopyroxene

    Science.gov (United States)

    Wang, Wenzhong; Zhou, Chen; Qin, Tian; Kang, Jin-Ting; Huang, Shichun; Wu, Zhongqing; Huang, Fang

    2017-12-01

    Concentration effect on equilibrium inter-mineral isotope fractionation is ubiquitous in solid solution systems, but it is not clear in which concentration range such effect is prominent. Using first-principles calculations, we examine the effect of Ca and Fe contents in orthopyroxene (opx) on its average Casbnd O bond length and the equilibrium Ca isotope fractionation factor (103lnα) between opx and clinopyroxene (cpx). Our results reveal that the average Casbnd O bond length in opx is much smaller than that in cpx and it does not change with variable Ca content x (x and y are mole ratios in CaxFeyMg1-x-ySiO3 thereafter here) when x ≤ 1/48. Incorporation of Fe (y ≥ 1/32) into opx with a fixed Ca content can only slightly increase the average Casbnd O bond length. 103lnαopx-cpx of 44Ca/40Ca is linearly correlated with the average Casbnd O bond length in opx, suggesting that 103lnαopx-cpx of 44Ca/40Ca is controlled by opx Casbnd O bond strength. Our calculations indicate that the Ca concentration effect on 103lnαopx-cpx is significant when x in opx ranges from 2/16 to 1/48, while Fe in natural opx only causes a slight decrease in 103lnαopx-cpx. Our results provide insights into Ca isotope fractionation in high-temperature geochemical processes. Given that Ca content x in opx from natural peridotites is usually lower than 1/32 and Fe content y is generally ∼10 mol%, Ca and Fe concentration effects on 103lnαopx-cpx in natural samples are negligible. Rather, 103lnαopx-cpx is mainly controlled by temperature. 103lnαopx-cpx of 44Ca/40Ca decreases from 0.50‰ to 0.26‰ when temperature increases from 1000 K to 1400 K if the Fe effect is taken into account. Therefore, if Ca isotope fractionation between opx and cpx (Δ44/40Caopx-cpx) in natural peridotites is greater than 0.50‰ or lower than 0.26‰, it may indicate disequilibrium of Ca isotopes. Finally, the large 103lnαopx-cpx relative to our current analytical precision suggests that Δ44/40Caopx

  7. Prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma

    Science.gov (United States)

    Wang, Wei; Chen, Xiao-Long; Zhao, Shen-Yu; Xu, Yu-Hui; Zhang, Wei-Han; Liu, Kai; Chen, Xin-Zu; Yang, Kun; Zhang, Bo; Chen, Zhi-Xin; Chen, Jia-Ping; Zhou, Zong-Guang; Hu, Jian-Kun

    2016-01-01

    The prognostic significance of preoperative serum CA125, CA19-9 and CEA in gastric carcinoma (GC) has been widely reported and is still under debate. Here, we evaluated the prognostic significance of preoperative serum CA125, CA19-9 and CEA in patients with GC. 1692 patients with GC who underwent gastrectomy were divided into the training (from January 2005 to December 2011, n = 1024) and the validation (from January 2012 to December 2013, n = 668) cohorts. Positive groups of CA125 (> 13.72 U/ml), CA19-9 (> 23.36 U/ml) and CEA (> 4.28 ng/ml) were significantly associated with more advanced clinicopathological traits and worse outcomes than that of negative groups (all P tumor size (P tumor markers (NPTM) were more accurate in prognostic prediction than TNM stage alone. Our findings suggested that elevated preoperative serum CA125, CA19-9 and CEA were associated with more advanced clinicopathological traits and less favorable outcomes. In addition, CA125 as an independent prognostic factor should be further investigated. Nomogram based on NPTM could accurately predict the prognosis of GC patients. PMID:27097114

  8. Ca adsorption on dickite, Sericite and quartz. Dickite, sericite oyobi sekiei ni taisuru Ca no kyuchaku

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Isao; Nozawa, Miki (Tohoku Univ., Sendai, (Japan). Faculty of Engineering)

    1990-02-25

    Ca adsorbing characteristics of dickite were studied to clarify the possibility of clay minerals on selective Ca activation. Ca adsorption on hydrogenated dickite was compared with those of Na {sup +} and K {sup +} and further, the comparison was made for adsorption of Ca and these ikns on quartz and hydrogenated sericite. Ca adsorption on quartz which is thought to be caused by the negative charge of broken bond, depends strongly on pH and for pH of 7 or more, Ca acts strongly on any quartz surface. Moreover, when Na {sup +} or K {sup +} coexists, the effect of coexisting ion on Ca adsorption does not result any difference. On the contrary, Ca adsorption on sericite is mainly caused by the exchanging adsorption with H {sup +} and Ca saturated adsortion does not depend on pH in the range of 4-10pH. But Na {sup +} adsorption does not reach the saturation for lower pH unless Na {sup +} of sufficient concentration exists. 13 refs., 16 figs.

  9. Dielectron production in p+Be and Ca+Ca collisions at the Bevalac

    Energy Technology Data Exchange (ETDEWEB)

    Roche, G.; Krebs, G.F.; Lallier, E.; Letessier-Selvon, A.; Matis, H.S.; Naudet, C.; Schroeder, L.; Seidl, P.A.; Yegneswaran, A.; Bystricky, J.; Carroll, J.; Gordon, J.; Igo, G.; Hallman, T.; Madansky, L.; Welsh, R.; Kirk, P.; Wang, Z.F.; Miller, D.; Landaud, G.

    1988-06-01

    Dielectron production has been measured in p+Be collisions at 1.0, 2.1 and 4.9 GeV, and in Ca+Ca at 1.0 and 2.0 GeV/A. The observation of a structure in the mass cross section at about two times the pion mass suggests that pion annihilation is the dominant production mechanism in p+Be above 2 GeV. Comparison of preliminary results from p+Be and Ca+Ca at 1 GeV/A is presented. 7 refs., 5 figs., 1 tab.

  10. Physical conditions in CaFe interstellar clouds

    OpenAIRE

    Gnacinski, P.; Krogulec, M.

    2007-01-01

    Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.

  11. Absolute Ca Isotopic Measurement Using an Improved Double Spike Technique

    Directory of Open Access Journals (Sweden)

    Jason Jiun-San Shen

    2009-01-01

    Full Text Available A new vector analytical method has been developed in order to obtain the true isotopic composition of the 42Ca-48Ca double spike. This is achieved by using two different sample-spike mixtures combined with the double spike and natural Ca data. Be cause the natural sample (two mixtures and the spike should all lie on a single mixing line, we are able to con strain the true isotopic composition of our double spike using this new approach. Once the isotopic composition of the Ca double spike is established, we are able to obtain the true Ca isotopic composition of the NIST Ca standard SRM915a, 40Ca/44Ca = 46.537 ± 2 (2sm, n = 55, 42Ca/44Ca = 0.31031 ± 1, 43Ca/44Ca = 0.06474 ± 1, and 48Ca/44Ca = 0.08956 ± 1. De spite an off set of 1.3% in 40Ca/44Ca between our result and the previously re ported value (Russell et al. 1978, our data indicate an off set of 1.89__in 40Ca/44Ca between SRM915a and seawater, entirely consistent with the published results.

  12. The destiny of Ca(2+) released by mitochondria.

    Science.gov (United States)

    Takeuchi, Ayako; Kim, Bongju; Matsuoka, Satoshi

    2015-01-01

    Mitochondrial Ca(2+) is known to regulate diverse cellular functions, for example energy production and cell death, by modulating mitochondrial dehydrogenases, inducing production of reactive oxygen species, and opening mitochondrial permeability transition pores. In addition to the action of Ca(2+) within mitochondria, Ca(2+) released from mitochondria is also important in a variety of cellular functions. In the last 5 years, the molecules responsible for mitochondrial Ca(2+) dynamics have been identified: a mitochondrial Ca(2+) uniporter (MCU), a mitochondrial Na(+)-Ca(2+) exchanger (NCLX), and a candidate for a mitochondrial H(+)-Ca(2+) exchanger (Letm1). In this review, we focus on the mitochondrial Ca(2+) release system, and discuss its physiological and pathophysiological significance. Accumulating evidence suggests that the mitochondrial Ca(2+) release system is not only crucial in maintaining mitochondrial Ca(2+) homeostasis but also participates in the Ca(2+) crosstalk between mitochondria and the plasma membrane and between mitochondria and the endoplasmic/sarcoplasmic reticulum.

  13. Changes in the expression of serum markers CA242, CA199, CA125, CEA, TNF-α and TSGF after cryosurgery in pancreatic cancer patients.

    Science.gov (United States)

    Zhou, Gang; Niu, Lizhi; Chiu, David; He, Lihua; Xu, Kecheng

    2012-07-01

    The presence of serum tumor markers, carbohydrate antigen 242 (CA242), carbohydrate antigen 199 (CA199), carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), tumor-supplied group of factors (TSGF) and tumor necrosis factor-α (TNF-α), is closely associated with invasion and metastasis of many malignancies. The expression of these markers were measured in serum taken from 37 pancreatic cancer patients prior to treatment. Levels of CA242, CA199, CA125, CEA and TNF-α expression correlated with tumor size, clinical stage, tumor differentiation, lymph node and liver metastasis (P markers were significantly reduced compared with levels prior to cryosurgery (P 0.05). Thus, cryosurgery is more effective than chemotherapy for decreasing CA242, CA199, CA125, CEA, TSGF and TNF-α serum levels in these patients.

  14. Treatment of Ruptured Ovarian Endometrioma with Extremely High CA 125, Moderately High CA 19-9 and CA 15-3 Level

    Directory of Open Access Journals (Sweden)

    Muzeyyen Duran

    2013-06-01

    Full Text Available In this case report, a ruptured ovarian endometrioma with a very high CA-125 level, moderately elevated CA 19-9, and CA 15-3 levels is presented. A 20 years old patient, complaining from pelvic pain, 5 cm adnexial mass was detected on left side. Biochemical examination was revealed very high CA-125 value (2556IU/ml, moderately elevated CA 19-9 (134IU/ml, and CA 15-3 (65IU/ml values. Laparoscopy was done and a ruptured ovarian endometrioma of 5 cm was seen during operation. After the total excision of the cyst, tumor markers fell rapidly. Very high CA-125 value, moderately elevated CA19-9, and CA 15-3 values can be seen in cases with ruptured endometrioma. In young patients, endometrioma must be considered firstly and laparoscopy should be applied instead of more invasive methods unless there was any finding or strong suspicion about malignancy.

  15. Control of ciliary motility by Ca sup 2+ : Integration of Ca sup 2+ -dependent functions and targets for Ca sup 2+ action

    Energy Technology Data Exchange (ETDEWEB)

    Evans, T.C.

    1988-01-01

    To identify functions that regulate Ca{sup 2+}-induced ciliary reversal in Paramecium, mutants defective in terminating depolarization-induced backward swimming were selected. Six independent recessive mutations (k-shy) comprising two complementation groups, k-shyA and k-shyB, were identified. All mutants exhibited prolonged backward swimming in depolarizing solutions. Voltage clamp studies revealed that mutant Ca{sup 2+} current amplitudes were reduced, but could be restored to wild type levels by EGTA injection. The recovery of the mutant Ca{sup 2+} current from Ca{sup 2+}-dependent inactivation, and the decay of the Ca{sup 2+}-dependent K{sup +} and Ca{sup 2+}-dependent Na{sup +} currents after depolarization were slow in k-shy compared to wild type. To identify protein targets of Ca{sup 2+} action, ciliary proteins that interact with calmodulin (CaM) were characterized. With a {sup 125}I-CaM blot assay, several CaM-binding proteins were identified including axonemal, soluble, and membrane-bound polypeptides. Competitive displacement studies with unlabeled Paramecium CaM, bovine CaM, and troponinC suggested that both protein types bind CaM with high affinity and specificity. To examine the presence of CaM-binding sites in intact axonemes, a filtration binding assay was developed.

  16. Modeling the contributions of Ca2+ flows to spontaneous Ca2+ oscillations and cortical spreading depression-triggered Ca2+ waves in astrocyte networks.

    Directory of Open Access Journals (Sweden)

    Bing Li

    Full Text Available Astrocytes participate in brain functions through Ca(2+ signals, including Ca(2+ waves and Ca(2+ oscillations. Currently the mechanisms of Ca(2+ signals in astrocytes are not fully clear. Here, we present a computational model to specify the relative contributions of different Ca(2+ flows between the extracellular space, the cytoplasm and the endoplasmic reticulum of astrocytes to the generation of spontaneous Ca(2+ oscillations (CASs and cortical spreading depression (CSD-triggered Ca(2+ waves (CSDCWs in a one-dimensional astrocyte network. This model shows that CASs depend primarily on Ca(2+ released from internal stores of astrocytes, and CSDCWs depend mainly on voltage-gated Ca(2+ influx. It predicts that voltage-gated Ca(2+ influx is able to generate Ca(2+ waves during the process of CSD even after depleting internal Ca(2+ stores. Furthermore, the model investigates the interactions between CASs and CSDCWs and shows that the pass of CSDCWs suppresses CASs, whereas CASs do not prevent the generation of CSDCWs. This work quantitatively analyzes the generation of astrocytic Ca(2+ signals and indicates different mechanisms underlying CSDCWs and non-CSDCWs. Research on the different types of Ca(2+ signals might help to understand the ways by which astrocytes participate in information processing in brain functions.

  17. Ventral tegmental area disruption selectively affects CA1/CA2 but not CA3 place fields during a differential reward working memory task.

    Science.gov (United States)

    Martig, Adria K; Mizumori, Sheri J Y

    2011-02-01

    Hippocampus (HPC) receives dopaminergic (DA) projections from the ventral tegmental area (VTA) and substantia nigra. These inputs appear to provide a modulatory signal that influences HPC dependent behaviors and place fields. We examined how efferent projections from VTA to HPC influence spatial working memory and place fields when the reward context changes. CA1 and CA3 process environmental context changes differently and VTA preferentially innervates CA1. Given these anatomical data and electrophysiological evidence that implicate DA in reward processing, we predicted that CA1 place fields would respond more strongly to both VTA disruption and changes in the reward context than CA3 place fields. Rats (N = 9) were implanted with infusion cannula targeting VTA and recording tetrodes aimed at HPC. Then they were tested on a differential reward, win-shift working memory task. One recording session consisted of 5 baseline and 5 manipulation trials during which place cells in CA1/CA2 (N = 167) and CA3 (N = 94) were recorded. Prior to manipulation trials rats were infused with either baclofen or saline and then subjected to control or reward conditions during which the learned locations of large and small reward quantities were reversed. VTA disruption resulted in an increase in errors, and in CA1/CA2 place field reorganization. There were no changes in any measures of CA3 place field stability during VTA disruption. Reward manipulations did not affect performance or place field stability in CA1/CA2 or CA3; however, changes in the reward locations "rescued" performance and place field stability in CA1/CA2 when VTA activity was compromised, perhaps by trigging compensatory mechanisms. These data support the hypothesis that VTA contributes to spatial working memory performance perhaps by maintaining place field stability selectively in CA1/CA2. Copyright © 2009 Wiley-Liss, Inc.

  18. Adverse bioenergetic consequences of Na+-Ca2+ exchanger-mediated Ca2+ influx in cardiac myocytes.

    Science.gov (United States)

    Kohlhaas, Michael; Maack, Christoph

    2010-11-30

    In heart failure, the Na+-Ca²+ exchanger (NCX) is upregulated and mediates Ca²+ influx (instead of efflux) during the cardiac action potential. Although this partly compensates for impaired sarcoplasmic reticulum Ca²+ release and supports inotropy, the energetic consequences have never been considered. Because NCX-mediated Ca²+ influx is rather slow and mitochondrial Ca²+ uptake (which stimulates NADH production by the Krebs cycle) is thought to be facilitated by high Ca²+ gradients in a "mitochondrial Ca²+ microdomain," we speculated that NCX-mediated Ca²+ influx negatively affects the bioenergetic feedback response. Methods and Results- With the use of a patch-clamp-based approach in guinea-pig myocytes, cytosolic and mitochondrial Ca²+ ([Ca²+](c) and [Ca²+](m), respectively) was determined within the same cell after varying Ca²+ influx via L-type Ca²+ channels (I(Ca,L)) or the NCX. The efficiency of mitochondrial Ca²+ uptake, indexed by the slope of plotting [Ca²+](m) against [Ca²+](c) during each Ca²+ transient, was maximal during I(Ca,L)-triggered sarcoplasmic reticulum Ca²+ release. Depletion of sarcoplasmic reticulum Ca²+ load and increased contribution of the NCX to cytosolic Ca²+ influx independently reduced the efficiency of mitochondrial Ca²+ uptake. The upstroke velocity of cytosolic Ca²+ transients closely correlated with the efficiency of mitochondrial Ca²+ uptake. Despite comparable [Ca²+](c), sarcoplasmic reticulum Ca²+ release, but not NCX-mediated Ca²+ influx, led to stimulation of Ca²+-sensitive dehydrogenases of the Krebs cycle. Conclusions- Increased contribution of the NCX to cytosolic Ca²+ transients, which occurs in cardiac myocytes from failing hearts, impairs mitochondrial Ca²+ uptake and the bioenergetic feedback response. This mechanism could contribute to energy starvation of failing hearts.

  19. Comparative study of structural, electronic and optical properties of Ca2Si, Ca2Ge, Ca2Sn, and Ca2Pb

    Science.gov (United States)

    Migas, D. B.; Miglio, Leo; Shaposhnikov, V. L.; Borisenko, V. E.

    2003-05-01

    We report ab initio results for the ground-state properties, band diagrams, density of states, and dielectric functions of Ca2Z (Z=Si, Ge, Sn, and Pb) both in the orthorhombic and cubic structures. The calculations are performed by means of total energy ultrasoft pseudopotential and full potential linearized augmented plane wave methods within local density and generalized gradient approximations. The estimated difference in the cohesion energy shows the orthorhombic structure to be the stable phase. We also demonstrate that these materials are semiconductors independently of the phase. A direct energy gap and sizable anisotropy in optical spectra characterize orthorhombic Ca2Z, whereas a competitive direct-indirect character of the gap and a high value of oscillator strength of the first direct transition are predicted for cubic Ca2Z.

  20. Synaptotagmin-7 is a principal Ca2+ sensor for Ca2+ -induced glucagon exocytosis in pancreas

    DEFF Research Database (Denmark)

    Gustavsson, Natalia; Wei, Shun-Hui; Hoang, Dong Nhut

    2009-01-01

    Hormones such as glucagon are secreted by Ca(2+)-induced exocytosis of large dense-core vesicles, but the mechanisms involved have only been partially elucidated. Studies of pancreatic beta-cells secreting insulin revealed that synaptotagmin-7 alone is not sufficient to mediate Ca(2+)-dependent...... insulin granule exocytosis, and studies of chromaffin cells secreting neuropeptides and catecholamines showed that synaptotagmin-1 and -7 collaborate as Ca(2+) sensors for exocytosis, and that both are equally involved. As no other peptide secretion was analysed, it remains unclear whether synaptotagmins...... generally act as Ca(2+) sensors in large dense-core vesicle exocytosis in endocrine cells, and if so, whether synaptotagmin-7 always functions with a partner in that role. In particular, far less is known about the mechanisms underlying Ca(2+)-triggered glucagon release from alpha-cells than insulin...

  1. Study on Ca2+ antagonistic effect and mechanism of Chinese herbal drugs using 45Ca

    International Nuclear Information System (INIS)

    Yang Yuanyou; Liu Ning; Mo Shangwu; Qiu Mingfeng; Jin Jiannan; Liao Jiali

    2002-01-01

    The Ca 2+ antagonistic effect and mechanism of Chinese herbal drugs are studied by using 45 Ca. The results indicate that potential-dependent Ca 2+ channel (PDC) and receptor-operated Ca 2+ channel (ROC) in cell membranes of smooth muscle can be blocked by several Chinese herbal drugs, including as Crocus sativus L., Carthamus L., Di-ao-xin-xue-kang (DAXXG) and Ginkgo biloba L. leaves. Among them Crocus sativus L. has the strongest antagonistic effect on Ca 2+ channel, while Ginkgo biloba L. leaves has no obvious effect. The whole prescription and the other functional drugs have significant effect on ROC and PDC. The compositions extracted by hexane have the strongest antagonistic. The wrinkled giant hyssop have five active compositions and Pei-lan have two active compositions

  2. Applicative Value of Serum CA19-9, CEA, CA125 and CA242 in Diagnosis and Prognosis for Patients with Pancreatic Cancer Treated by Concurrent Chemoradiotherapy.

    Science.gov (United States)

    Gu, Yu-Lei; Lan, Chao; Pei, Hui; Yang, Shuang-Ning; Liu, Yan-Fen; Xiao, Li-Li

    2015-01-01

    To evaluate the application value of serum CA19-9, CEA, CA125 and CA242 in diagnosis and prognosis of pancreatic cancer cases treated with concurrent chemotherapy. 52 patients with pancreatic cancer, 40 with benign pancreatic diseases and 40 healthy people were selected. The electrochemiluminescence immunoassay method was used for detecting levels of CA19-9, CEA and CA125, and a CanAg CA242 enzyme linked immunoassay kit for assessing the level of CA242. The Kaplan-Meier method was used for analyzing the prognostic factors of patients with pancreatic cancer. The Cox proportional hazard model was applied for analyzing the hazard ratio (HR) and 95% confidential interval (CI) for survival time of patients with pancreatic cancer. The levels of serum CA19-9, CEA, CA125 and CA242 in patients with pancreatic cancer were significantly higher than those in patients with benign pancreatic diseases and healthy people (PCEA. The specificity of CA242 is the highest, followed by CA125, CEA and CA19-9. The sensitivity and specificity of joint detection of serum CA19-9, CEA, CA125and CA242 were 90.4% and 93.8%, obviously higher than single detection of those markers in diagnosis of pancreatic cancer. The median survival time of 52 patients with pancreatic cancer was 10 months (95% CI7.389~12.611).. Patients with the increasing level of serum CA19-9, CEA, CA125, CA242 had shorter survival times (P=0.047. 0.043, 0.0041, 0.029). COX regression analysis showed that CA19-9 was an independent prognostic factor for patients with pancreatic cancer (P=0.001, 95%CI 2.591~38.243). The detection of serum tumor markers (CA19.9, CEA, CA125 and CA242) is conducive to the early diagnosis of pancreatic cancer and joint detection of tumor markers helps improve the diagnostic efficiency. Moreover, CA19-9 is an independent prognostic factor for patients with pancreatic cancer.

  3. Measurements of hyperfine constants in Ca+

    International Nuclear Information System (INIS)

    Goble, A.T.; Maleki, S.

    1990-01-01

    We have measured the hyperfine constants A( 2 S 1/2 ), A( 2 P 1/2 ), and A( 2 P 3/2 ) for Ca + . We compare our results with the calculations of Martensson-Pendrill and Salomonson [Phys. Rev. A 30, 712 (1984)], who used many-body perturbation theory (MBPT). The agreement between our results and MBPT calculations for Ca + is about 3%, which is comparable to similar comparisons reported for Cs [S. Blundell, in 2 Relativistic, Quantum Electrodynamic, and Weak Interaction Effects in Atoms, AIP Conf. Proc. No. 189, edited by Walter Johnson, Peter Mohr, and Joseph Sucher (AIP, New York, 1988)

  4. The hippocampal CA2 ensemble is sensitive to contextual change.

    Science.gov (United States)

    Wintzer, Marie E; Boehringer, Roman; Polygalov, Denis; McHugh, Thomas J

    2014-02-19

    Contextual learning involves associating cues with an environment and relating them to past experience. Previous data indicate functional specialization within the hippocampal circuit: the dentate gyrus (DG) is crucial for discriminating similar contexts, whereas CA3 is required for associative encoding and recall. Here, we used Arc/H1a catFISH imaging to address the contribution of the largely overlooked CA2 region to contextual learning by comparing ensemble codes across CA3, CA2, and CA1 in mice exposed to familiar, altered, and novel contexts. Further, to manipulate the quality of information arriving in CA2 we used two hippocampal mutant mouse lines, CA3-NR1 KOs and DG-NR1 KOs, that result in hippocampal CA3 neuronal activity that is uncoupled from the animal's sensory environment. Our data reveal largely coherent responses across the CA axis in control mice in purely novel or familiar contexts; however, in the mutant mice subject to these protocols the CA2 response becomes uncoupled from CA1 and CA3. Moreover, we show in wild-type mice that the CA2 ensemble is more sensitive than CA1 and CA3 to small changes in overall context. Our data suggest that CA2 may be tuned to remap in response to any conflict between stored and current experience.

  5. Electrochemical formation of Mg-Li-Ca alloys by codeposition of Mg, Li and Ca from LiCl-KCl-MgCl2-CaCl2 melts.

    Science.gov (United States)

    Yan, Yong De; Zhang, Mi Lin; Xue, Yun; Han, Wei; Cao, Dian Xue; Jing, Xiao Yan; He, Li Yi; Yuan, Yi

    2009-08-07

    This work presents electrochemical formation of Mg-Li-Ca alloys via codeposition of Mg, Li and Ca on a molybdenum electrode in KCl-LiCl-MgCl(2)-CaCl(2) melts at 943 K. Cyclic voltammograms (CVs) showed that the underpotential deposition (UPD) of calcium on pre-deposited magnesium leads to the formation of a liquid Mg-Ca alloy, and the succeeding underpotential deposition of lithium on pre-deposited Mg-Ca alloy leads to the formation of a liquid Mg-Li-Ca solution. Chronopotentiometric measurements indicated that the codepositon of Mg, Li and Ca occurs at current densities more negative than -0.31 A cm(-2) in LiCl-KCl-MgCl(2) (5 wt%) melts containing 1 wt% CaCl(2). Chronoamperograms demonstrated that the onset potential for the codeposition of Mg, Li and Ca is -2.200 V, and the codeposition of Mg, Li and Ca is formed when the applied potentials are more negative than -2.200 V. X-Ray diffraction (XRD) indicated that Mg-Li-Ca alloys with different phases were formed via galvanostatic electrolysis. The microstructures of typical alpha and beta phases of Mg-Li-Ca alloys were characterized by optical microscope (OM) and scanning electron microscopy (SEM). The analysis of energy dispersive spectrometry (EDS) showed that the element Ca mainly distributes along grain boundary in Mg-Li-Ca alloys. The results of inductively coupled plasma analysis determined that the chemical compositions of Mg-Li-Ca alloys correspond with the phase structures of XRD patterns, and the lithium and calcium contents of Mg-Li-Ca alloys depend on the concentrations of MgCl(2) and CaCl(2).

  6. Value of Combined Detection of Serum CEA, CA72-4, CA19-9, CA15-3 and CA12-5 in the Diagnosis of Gastric Cancer.

    Science.gov (United States)

    Chen, Changguo; Chen, Qiuyuan; Zhao, Qiangyuan; Liu, Min; Guo, Jianwei

    2017-05-01

    To examine whether the combined detection of serum tumor markers (CEA, CA72-4, CA19-9, CA15-3 and CA12-5) improves the sensitivity and accuracy in the diagnosis of gastric cancer (GC). An automatic chemiluminescence immune analyzer with matched kits was used to determine the levels of serum CEA, CA72-4, CA19-9, CA15-3, and CA12-5 in 87 patients with gastric cancer (GC group), 60 patients with gastric benign diseases (GBD group) who were hospitalized during the same period, and 40 healthy subjects undergoing a physical examination. The values of these 5 tumor markers in the diagnosis of gastric cancer were analyzed. The levels of serum CEA, CA72-4, CA19-9, and CA12-5 were higher in the GC group than in the GBD group and healthy subjects, and these differences were significant ( P 0.05). The combined detection of CEA, CA72-4, CA19-9, and CA12-5 had a higher diagnostic value for gastric cancer than did single detection, and the positive detection rate of the combined detection of the four tumor markers was 60.9%. The diagnostic power when using the combined detection of CA72-4, CEA, CA19-9, and CA12-5 was the best. The combined detection of serum CA72-4, CEA, CA19-9 and CA12-5 increases the sensitivity and accuracy in the diagnosis of GC and can thus be considered an important tool for early diagnosis. © 2017 by the Association of Clinical Scientists, Inc.

  7. Ca and Mg binding induce conformational stability of Calfumirin-1 ...

    Indian Academy of Sciences (India)

    loops of CaBPs to accommodate the hexagonally coor- dinated metal ion.19–24 The different ionic radii of the two ions (Ca2+ = 1.14 Å and Mg2+ = 0.86 Å) enable specificity of CaBPs towards Ca2+ over Mg2+ binding, with distinguished affinity towards CaBPs.23 As there is a high concentration of Mg2+ in the cell, the bind-.

  8. Towards ultracold RbCa molecules

    Science.gov (United States)

    Kleinert, Michaela; Whitson, Hayley; Parsagian, Alexandria

    2012-06-01

    Ultracold heteronuclear molecules have seen increasing interest in the scientific community over the last few years. By controlling their ro-vibrational energy levels, ultracold molecules can be used for high precision spectroscopy, to study cold collisions with rich internal dynamics, as model systems for condensed matter physics, and as qubits in quantum information processing. We study the novel combination RbCa. In addition to a permanent electric dipole moment, it also possesses a permanent magnetic dipole moment. This makes it an ideal candidate to study strong long-range dipole-dipole interactions. We are currently in the process of adding a Ca MOT to our existing Rb MOT and will discuss our current and future efforts toward our goal of creating, for the first time, ultracold RbCa molecules. Molecules, once created, will be detected through resonantly enhanced multi-photon ionization (REMPI). We have also performed ab initio calculations to determine the electronic energy levels of RbCa, and calculated Franck-Condon factors between the ground and several excited states

  9. Ca teos report in register N 13377

    International Nuclear Information System (INIS)

    Pena, S; Arrighetti, R.

    2011-01-01

    This work is about a report about ca teos carried out in register N 13377 in the department of Canelones to know the depth of the field. The drilling done allowed to identify granite and clay. This granite outcrops are developed in the east of the middle course of the stream Pando

  10. literacy.ca EXPRESS. April 2010

    Science.gov (United States)

    Movement for Canadian Literacy, 2010

    2010-01-01

    This issue of "literacy.ca EXPRESS" focuses on poverty. The articles included in this issue are: (1) Poverty Overview; (2) Tony's Story; (3) LAN (Learner Advisory Network) Member's Story (Dianne Smith); (4) Linking Adult Literacy to Poverty Reduction; (5) MCL (Movement for Canadian Literacy) Update; (6) Highlights from the LAN; (7) Good…

  11. Elastic and inelastic scattering of 1.044 GeV protons by 40Ca, 42Ca, 44Ca, 48Ca and 48Ti

    International Nuclear Information System (INIS)

    Alkhazov, G.D.; Bauer, T.; Beurtey, R.; Boudard, A.; Bruge, G.; Chaumeaux, A.; Couvert, P.; Cvijanovich, G.; Duhm, H.H.; Fontaine, J.M.; Garreta, D.; Kulikov, A.V.; Legrand, D.; Lugol, J.C.; Saudinos, J.; Thirion, J.; Vorobyov, A.A.

    1976-01-01

    Elastic and inelastic scattering of 1.044 GeV protons have been studied on isotopically enriched even 40 42 48 48 Ca isotopes and 48 Ti. A spin independent Glauber theory analysis of the elastic scattering allowed the extraction of neutron and nuclear matter densities for these targets. (Auth.)

  12. Thapsigargin, a tumor promoter, discharges intracellular Ca2+ stores by specific inhibition of the endoplasmic reticulum Ca2(+)-ATPase

    DEFF Research Database (Denmark)

    Thastrup, Ole; Cullen, P J; Drøbak, B K

    1990-01-01

    + in sensitive cells by an acute and highly specific arrest of the endoplasmic reticulum Ca2+ pump, followed by a rapid Ca2+ leak from at least two pharmacologically distinct Ca2+ stores. The implications of this mechanism of action for the application of thapsigargin in the analysis of Ca2+ homeostasis...

  13. ASteCA: Automated Stellar Cluster Analysis

    Science.gov (United States)

    Perren, G. I.; Vázquez, R. A.; Piatti, A. E.

    2015-04-01

    We present the Automated Stellar Cluster Analysis package (ASteCA), a suit of tools designed to fully automate the standard tests applied on stellar clusters to determine their basic parameters. The set of functions included in the code make use of positional and photometric data to obtain precise and objective values for a given cluster's center coordinates, radius, luminosity function and integrated color magnitude, as well as characterizing through a statistical estimator its probability of being a true physical cluster rather than a random overdensity of field stars. ASteCA incorporates a Bayesian field star decontamination algorithm capable of assigning membership probabilities using photometric data alone. An isochrone fitting process based on the generation of synthetic clusters from theoretical isochrones and selection of the best fit through a genetic algorithm is also present, which allows ASteCA to provide accurate estimates for a cluster's metallicity, age, extinction and distance values along with its uncertainties. To validate the code we applied it on a large set of over 400 synthetic MASSCLEAN clusters with varying degrees of field star contamination as well as a smaller set of 20 observed Milky Way open clusters (Berkeley 7, Bochum 11, Czernik 26, Czernik 30, Haffner 11, Haffner 19, NGC 133, NGC 2236, NGC 2264, NGC 2324, NGC 2421, NGC 2627, NGC 6231, NGC 6383, NGC 6705, Ruprecht 1, Tombaugh 1, Trumpler 1, Trumpler 5 and Trumpler 14) studied in the literature. The results show that ASteCA is able to recover cluster parameters with an acceptable precision even for those clusters affected by substantial field star contamination. ASteCA is written in Python and is made available as an open source code which can be downloaded ready to be used from its official site.

  14. Effects of Ca on microstructure, mechanical and corrosion properties and biocompatibility of Mg-Zn-Ca alloys.

    Science.gov (United States)

    Yin, Ping; Li, Nian Feng; Lei, Ting; Liu, Lin; Ouyang, Chun

    2013-06-01

    Zn and Ca were selected as alloying elements to develop an Mg-Zn-Ca alloy system for biomedical application due to their good biocompatibility. The effects of Ca on the microstructure, mechanical and corrosion properties as well as the biocompatibility of the as-cast Mg-Zn-Ca alloys were studied. Results indicate that the microstructure of Mg-Zn-Ca alloys typically consists of primary α-Mg matrix and Ca₂Mg₆Zn₃/Mg₂Ca intermetallic phase mainly distributed along grain boundary. The yield strength of Mg-Zn-Ca alloy increased slightly with the increase of Ca content, whilst its tensile strength increased at first and then decreased. Corrosion tests in the simulated body fluid revealed that the addition of Ca is detrimental to corrosion resistance due to the micro-galvanic corrosion acceleration. In vitro hemolysis and cytotoxicity assessment disclose that Mg-5Zn-1.0Ca alloy has suitable biocompatibility.

  15. Mg and Ca isotope fractionation during CaCO3 biomineralisation.

    Science.gov (United States)

    Chang, Veronica T-C; Williams, R J P; Makishima, Akio; Belshawl, Nick S; O'Nions, R Keith

    2004-10-08

    The natural variation of Mg and Ca stable isotopes of carbonates has been determined in carbonate skeletons of perforate foraminifera and reef coral together with Mg/Ca ratios to assess the influence of biomineralisation processes. The results for coral aragonite suggest its formation, in terms of stable isotope behaviour, approximates to inorganic precipitation from a seawater reservoir. In contrast, results for foraminifera calcite suggest a marked biological control on Mg isotope ratios presumably related to its low Mg content compared with seawater. The bearing of these observations on the use of Mg and Ca isotopes as proxies in paleoceanography is considered. Copyright 2004 Elsevier Inc.

  16. Reassigning the CaH+ 11Σ → 21Σ vibronic transition with CaD+

    Science.gov (United States)

    Condoluci, J.; Janardan, S.; Calvin, A. T.; Rugango, R.; Shu, G.; Sherrill, C. D.; Brown, K. R.

    2017-12-01

    We observe vibronic transitions in CaD+ between the 11Σ and 21Σ electronic states by resonance enhanced multiphoton photodissociation spectroscopy in a Coulomb crystal. The vibronic transitions are compared with previous measurements on CaH+. The result is a revised assignment of the CaH+ vibronic levels and a disagreement with multi-state-complete-active-space second-order perturbation theory theoretical calculations by approximately 700 cm-1. Updated high-level coupled-cluster calculations that include core-valence correlations reduce the disagreement between theory and experiment to 300 cm-1.

  17. Interlaboratory study for coral Sr/Ca and other element/Ca ratio measurements

    OpenAIRE

    Hathorne, Ed C.; Gagnon, Alex; Felis, Thomas; Adkins, Jess; Asami, Ryuji; Boer, Wim; Caillon, Nicolas; Case, David; Cobb, Kim M.; Douville, Eric; deMenocal, Peter; Eisenhauer, Anton; Garbe-Schönberg, Dieter; Geibert, Walter; Goldstein, Steven L.

    2013-01-01

    The Sr/Ca ratio of coral aragonite is used to reconstruct past sea surface temperature (SST). Twenty-one laboratories took part in an interlaboratory study of coral Sr/Ca measurements. Results show interlaboratory bias can be significant, and in the extreme case could result in a range in SST estimates of 7 degrees C. However, most of the data fall within a narrower range and the Porites coral reference material JCp-1 is now characterized well enough to have a certified Sr/Ca value of 8.838 m...

  18. Thermoluminescence of CaCO3:Dy and CaCO3:Mn

    International Nuclear Information System (INIS)

    Bapat, V.N.; Nambi, K.S.V.

    1976-01-01

    CaCO 3 samples doped with Dy and Mn were prepared in the laboratory by co-precipitation techniques. Thermoluminescence and emission spectra of these phosphors were studied and were compared with those of the naturally occuring calcite and undoped CaCO 3 samples. Dy-doping seems to give a more efficient phosphor and indicates a possibility of getting a better phosphor by a judicious choice of a rare earth doping of CaCO 3 . Interesting result have been obtained on the TL glow curve variations of these phosphors with different temperature treatments prior to irradiation. (author)

  19. Extra-matrix Mg2+ limits Ca2+ uptake and modulates Ca2+ uptake-independent respiration and redox state in cardiac isolated mitochondria

    NARCIS (Netherlands)

    Boelens, Age D.; Pradhan, Ranjan K.; Blomeyer, Christoph A.; Camara, Amadou K. S.; Dash, Ranjan K.; Stowe, David F.

    2013-01-01

    Cardiac mitochondrial matrix (m) free Ca(2+) ([Ca(2+)]m) increases primarily by Ca(2+) uptake through the Ca(2+) uniporter (CU). Ca(2+) uptake via the CU is attenuated by extra-matrix (e) Mg(2+) ([Mg(2+)]e). How [Ca(2+)]m is dynamically modulated by interacting physiological levels of [Ca(2+)]e and

  20. Serum concentrations of the biomarkers CA125, CA15-3, CA72-4, tPSA and PAPP-A in natural and stimulated ovarian cycles

    Directory of Open Access Journals (Sweden)

    Melissa Stemp

    2014-06-01

    Conclusion: Ovarian stimulation reduced serum PAPP‐A levels, CA125 and CA15‐3 levels were generally unaffected by ovarian stimulation but displayed cyclical changes throughout both natural and stimulated cycles, whilst tPSA and CA72-4 were not affected by the stage of the cycle or ovarian stimulation.

  1. Hydrogen peroxide inhibits Ca2+efflux through plasma membrane Ca2+-ATPase in mouse parotid acinar cells.

    Science.gov (United States)

    Kim, Min Jae; Choi, Kyung Jin; Yoon, Mi Na; Oh, Sang Hwan; Kim, Dong Kwan; Kim, Se Hoon; Park, Hyung Seo

    2018-03-01

    Intracellular Ca 2+ mobilization is closely linked with the initiation of salivary secretion in parotid acinar cells. Reactive oxygen species (ROS) are known to be related to a variety of oxidative stress-induced cellular disorders and believed to be involved in salivary impairments. In this study, we investigated the underlying mechanism of hydrogen peroxide (H 2 O 2 ) on cytosolic Ca 2+ accumulation in mouse parotid acinar cells. Intracellular Ca 2+ levels were slowly elevated when 1 mM H 2 O 2 was perfused in the presence of normal extracellular Ca 2+ . In a Ca 2+ -free medium, 1 mM H 2 O 2 still enhanced the intracellular Ca 2+ level. Ca 2+ entry tested using manganese quenching technique was not affected by perfusion of 1 mM H 2 O 2 . On the other hand, 10 mM H 2 O 2 induced more rapid Ca 2+ accumulation and facilitated Ca 2+ entry from extracellular fluid. Ca 2+ refill into intracellular Ca 2+ store and inositol 1,4,5-trisphosphate (1 µM)-induced Ca 2+ release from Ca 2+ store was not affected by 1 mM H 2 O 2 in permeabilized cells. Ca 2+ efflux through plasma membrane Ca 2+ -ATPase (PMCA) was markedly blocked by 1 mM H 2 O 2 in thapsigargin-treated intact acinar cells. Antioxidants, either catalase or dithiothreitol, completely protected H 2 O 2 -induced Ca 2+ accumulation through PMCA inactivation. From the above results, we suggest that excessive production of H 2 O 2 under pathological conditions may lead to cytosolic Ca 2+ accumulation and that the primary mechanism of H 2 O 2 -induced Ca 2+ accumulation is likely to inhibit Ca 2+ efflux through PMCA rather than mobilize Ca 2+ ions from extracellular medium or intracellular stores in mouse parotid acinar cells.

  2. Ca2+ alternans in a cardiac myocyte model that uses moment equations to represent heterogeneous junctional SR Ca2+.

    Science.gov (United States)

    Huertas, Marco A; Smith, Gregory D; Györke, Sándor

    2010-07-21

    Multiscale whole-cell models that accurately represent local control of Ca2+-induced Ca2+ release in cardiac myocytes can reproduce high-gain Ca2+ release that is graded with changes in membrane potential. Using a recently introduced formalism that represents heterogeneous local Ca2+ using moment equations, we present a model of cardiac myocyte Ca2+ cycling that exhibits alternating sarcoplasmic reticulum (SR) Ca2+ release when periodically stimulated by depolarizing voltage pulses. The model predicts that the distribution of junctional SR [Ca2+] across a large population of Ca2+ release units is distinct on alternating cycles. Load-release and release-uptake functions computed from this model give insight into how Ca2+ fluxes and stimulation frequency combine to determine the presence or absence of Ca2+ alternans. Our results show that the conditions for the onset of Ca2+ alternans cannot be explained solely by the steepness of the load-release function, but that changes in the release-uptake process also play an important role. We analyze the effect of the junctional SR refilling time constant on Ca2+ alternans and conclude that physiologically realistic models of defective Ca2+ cycling must represent the dynamics of heterogeneous junctional SR [Ca2+] without assuming rapid equilibration of junctional and network SR [Ca2+]. Copyright (c) 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  3. Phosphorylation and activation of nuclear Ca{sup 2+}/calmodulin-dependent protein kinase phosphatase (CaMKP-N/PPM1E) by Ca{sup 2+}/calmodulin-dependent protein kinase I (CaMKI)

    Energy Technology Data Exchange (ETDEWEB)

    Onouchi, Takashi [Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795 (Japan); Sueyoshi, Noriyuki, E-mail: sueyoshi@ag.kagawa-u.ac.jp [Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795 (Japan); Ishida, Atsuhiko [Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521 (Japan); Kameshita, Isamu [Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795 (Japan)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer CaMKP-N/PPM1E underwent proteolytic processing and translocated to cytosol. Black-Right-Pointing-Pointer The proteolysis was effectively inhibited by the proteasome inhibitors. Black-Right-Pointing-Pointer Ser-480 of zebrafish CaMKP-N was phosphorylated by cytosolic CaMKI. Black-Right-Pointing-Pointer Phosphorylation-mimic mutants of CaMKP-N showed enhanced activity. Black-Right-Pointing-Pointer These results suggest that CaMKP-N is regulated by CaMKI. -- Abstract: Nuclear Ca{sup 2+}/calmodulin-dependent protein kinase phosphatase (CaMKP-N/PPM1E) is an enzyme that dephosphorylates and downregulates multifunctional Ca{sup 2+}/calmodulin-dependent protein kinases (CaMKs) as well as AMP-dependent protein kinase. In our previous study, we found that zebrafish CaMKP-N (zCaMKP-N) underwent proteolytic processing and translocated to cytosol in a proteasome inhibitor-sensitive manner. In the present study, we found that zCaMKP-N is regulated by phosphorylation at Ser-480. When zCaMKP-N was incubated with the activated CaMKI, time-dependent phosphorylation of the enzyme was observed. This phosphorylation was significantly reduced when Ser-480 was replaced by Ala, suggesting that CaMKI phosphorylates Ser-480 of zCaMKP-N. Phosphorylation-mimic mutants, S480D and S480E, showed higher phosphatase activities than those of wild type and S480A mutant in solution-based phosphatase assay using various substrates. Furthermore, autophosphorylation of CaMKII after ionomycin treatment was more severely attenuated in Neuro2a cells when CaMKII was cotransfected with the phosphorylation-mimic mutant of zCaMKP-N than with the wild-type or non-phosphorylatable zCaMKP-N. These results strongly suggest that phosphorylation of zCaMKP-N at Ser-480 by CaMKI activates CaMKP-N catalytic activity and thereby downregulates multifunctional CaMKs in the cytosol.

  4. Materials compatibility during the chlorination of molten CaCl2 . CaO salts

    International Nuclear Information System (INIS)

    Rense, C.E.C.; Fife, K.W.; Bowersox, D.F.; Ferran, M.D.

    1987-01-01

    As part of our effort to develop a semicontinuous PuO 2 reduction process, we are investigating promising materials for containing a 900 0 C molten CaCl 2 . CaO chlorination reaction. We want the material to contain this reaction and to be reusable. We tested candidate materials in a simulated salt (no plutonium) using anhydrous HCl as the chlorinating agent. Data are presented on the performance of 36 metals and alloys, 9 ceramics, and 3 coatings

  5. Anode process on platinum in CaCl2-CaO-based melt

    Directory of Open Access Journals (Sweden)

    K. V. Tatarenko

    2014-12-01

    Full Text Available Methods potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic processes on platinum in the molten CaCl2-KCl-CaO when 725–775 °C. Given thermodynamic values of potential difference probable total reactions in the range of the studied temperature. Using potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic process on platinum in the molten CaCl2-KCl-CaO when 725–775 °C thermodynamic assessment of the probability of occurrence total reactions during electrolysis melt on the basis of CaCl2-CaO using non-carbon anode. It is shown that at high current densities anodic process takes place mainly in the conditions of slow diffusion of electrically active particles to the anode, and at low densities (up to 10 mA/cm2 to their discharge to the atomic and lecular oxygen is preceded by a stage, which can be associated with adsorption of atoms of oxygen or with the formation of an oxide film on the surface of platinum. To detect the nature of this stage, further research is needed.

  6. Diagnostic significance of tumor markers CEA, CA50 and CA19-9 for colorectal cancer

    International Nuclear Information System (INIS)

    Chen Yumei; Huang Gang

    2005-01-01

    Objective: To investigate the expression and diagnostic significance of three serum tumor markers (CEA, CA50, CA19-9) in patients with colorectal cancer, with special emphasis on their combined assay. Methods: Serum CEA, CA19-9 levels (with chemiluminescence immunoassay) and CA50 levels (with immunoradiometric assay) were determined in 94 patients with colorectal cancer, 20 patients with benign colorectal disorders and 37 controls. Results: The expressions of the serum tumor markers were significantly higher in patients with colorectal cancer than those in patients with benign colorectal disorders and controls (P<0.05). There was no significant difference between the levels in the latter two groups. CEA assay had the highest sensitivity (57.4%) and specificity (85.9%). Combined assay of the three could enhance both the sensitivity (62.7%) and specificity (96.5%). The serum levels of the markers were significantly higher in patients with colonic cancer than those in patients with rectal cancer (P<0.05). The levels were positively correlated with the size of the growth and stage of the disease. Serum tumor marker levels were also significantly higher in patients with metastasis (regional/distant) than those in patients without metastasis (P<0.05). Conclusion: Determination of serum CEA, CA50 and CA19-9 levels had definite value for the diagnosis and assessment of the pathology as well as biologic behavior colorectal cancer. Combined assay of the three could enhance the diagnostic sensitivity and specificity. (authors)

  7. Neuronal Ca(2+) dyshomeostasis in Huntington disease.

    Science.gov (United States)

    Giacomello, Marta; Oliveros, Juan C; Naranjo, Jose R; Carafoli, Ernesto

    2013-01-01

    The expansion of the N-terminal poly-glutamine tract of the huntingtin (Htt) protein is responsible for Huntington disease (HD). A large number of studies have explored the neuronal phenotype of HD, but the molecular aethiology of the disease is still very poorly understood. This has hampered the development of an appropriate therapeutical strategy to at least alleviate its symptoms. In this short review, we have focused our attention on the alteration of a specific cellular mechanism common to all HD models, either genetic or induced by treatment with 3-NPA, i.e. the cellular dyshomeostasis of Ca(2+). We have highlighted the direct and indirect (i.e. transcriptionally mediated) effects of mutated Htt on the maintenance of the intracellular Ca(2+) balance, the correct modulation of which is fundamental to cell survival and the disturbance of which plays a key role in the death of the cell.

  8. Time-resolved fluoroimmunoassay of CA125

    International Nuclear Information System (INIS)

    Cai Gangming; Huang Biao; Zhu Liguo; Xiao Hualong; Tan Cheng; Tao Yonghui; Jin Jian

    2001-01-01

    A two-site time-resolved fluoroimmunoassay (TRFIA) of CA 125 based on the direct sandwich technique has been developed, with the equilibrium method. The monoclonal antibody (MoAb) against CA 125 was labelled with europium by the help of europium-chelate of diethylenetriaminepentaacetic acid (DTPA). The luminescent enhancement system was an enhancement solution that contained mainly of 2-naphthoyltrifluoroacetone. The intra- and inter- assay CV of the TRFIA were 4.5% and 4.0%, respectively, and the recovery rate was 96.7%, the sensitivity was 3.3 μg/mL. The cross-reacting rate with CEA was negligible, and that with AFP and β-HCG was 4.6% and 12.4%, respectively. Compared with the imported IRMA Kit, the correlation coefficient was 0.999

  9. The Reliability of Highly Elevated CA 19-9 Levels

    Directory of Open Access Journals (Sweden)

    B. R. Osswald

    1993-01-01

    Full Text Available CA 19-9 is used as a tumour marker of the upper gastrointestinal tract. However, extremely elevated CA 19-9 levels are found also in patients with benign diseases. Cholestasis was present in 97.1 % of patients with high elevated CA 19-9, independent of their primary disease. 50% of patients with non-malignant diseases and increased CA 19-9 levels showed liver cirrhosis, cholecystitis, pancreatitis and/or hepatitis. In 8.8% no explanation was found for the extremely high CA 19-9 level. The results provide evidence of different factors influencing the CA 19-9 level.

  10. Astrocyte Ca2+ signalling: an unexpected complexity

    OpenAIRE

    Volterra, Andrea; Liaudet, Nicolas; Savtchouk, Iaroslav

    2014-01-01

    Astrocyte Ca(2+) signalling has been proposed to link neuronal information in different spatial-temporal dimensions to achieve a higher level of brain integration. However, some discrepancies in the results of recent studies challenge this view and highlight key insufficiencies in our current understanding. In parallel, new experimental approaches that enable the study of astrocyte physiology at higher spatial-temporal resolution in intact brain preparations are beginning to reveal an unexpec...

  11. Mg,Ca-ATPase activity under irradiation

    International Nuclear Information System (INIS)

    Ladutin, V.V.; Orlova, V.V.; Lob, P.A.; Gerasiminko, I.V.; Mack, E.I.

    2003-01-01

    Full text: The influence of different doses irradiation at the Mg,Ca-ATPase activity at the rat brain has been investigated. The analyses were made at the apparatus of LKB and Carl-Ceis-Jena firm with help of reagents of Sigma and Boehringer firm. Rats decapitated after 1, 3, 6, 24 and 48 h after action of irradiation. Dose 0.206 C/kg. Erythrocytes. 1 and 3h after irradiation influence- decrease of Mg,Ca-ATPase activity to 86-87% relatively control level, 24 and 48 h - increase of activity to the control level. Dose 0.312 C/kg. Large hemispheres. 1h - decrease of ATPase activity to 90% relatively control, 3h - increase to control level, 24h - fall to 86%, after 48h small increase to 93% relatively control. Dose 9.287 C/kg. Large hemispheres. 1h - sharp fall of Mg, Ca-ATPase activity to 67 % relatively control, increase of activity to 96% after 3h and sharp fall of activity to 64% 6h after action of irradiation. Dose 9.287 C/kg. Cerebellum. 1h - sharp decrease of ATPase activity to 80%. After 3h -sharp increase to 160% relatively control level and sharp fall of ATPase activity to 47% relatively control after 6h. The mechanism of radiation pathology of active ion transport has been discussed

  12. Glucagon releases Ca2+ from a FCCP-sensitive pool

    International Nuclear Information System (INIS)

    Kraus-Friedmann, N.

    1986-01-01

    The effects of physiological levels of glucagon on Ca 2+ efflux were examined in the perfused rat liver. Two methods were used to estimate Ca 2+ efflux: (1) prior labeling of the Ca 2+ pools with 45 Ca 2+ , and (2) measurement of perfusate Ca 2+ with atomic absorption. According to both methods, glucagon administration at the physiological level evoked Ca 2+ release. In order to identify the hormone-sensitive Ca 2+ pool, a method employed by several laboratories was used. In this method, mitochondrial Ca 2+ is released by FCCP, (carbonyl-cyanide 4 (trifluoro/methoxy) phenylhydrazone), a mitochondrial uncoupler. The effect of hormones on Ca 2+ release after such uncoupler administration is measured. A decreased release is taken as an indication that the pool is entirely or partially mitochondrial. FCCP released 90 +/- 29 nmoles Ca 2+ /gr wet liver. Glucagon (5 x 10 -9 M) released 107 +/- 45 nmoles Ca 2+ /gr wet liver before and 26 +/- 9 nmoles Ca 2+ /gr wet liver after FCCP. These data indicate that glucagon releases Ca 2+ mostly from the mitochondria

  13. CaMKII: linking heart failure and arrhythmias

    Science.gov (United States)

    Swaminathan, Paari Dominic; Purohit, Anil; Hund, Thomas J; Anderson, Mark E

    2013-01-01

    Understanding relationships between heart failure and arrhythmias, important causes of suffering and sudden death, remains an unmet goal for biomedical researchers and physicians. Evidence assembled over the last decade supports a view that activation of the multifunctional Ca2+ and calmodulin-dependent protein kinase II (CaMKII) favors myocardial dysfunction and cell membrane electrical instability. CaMKII activation follows increases in intracellular Ca2+ or oxidation, upstream signals with the capacity to transition CaMKII into a Ca2+ and calmodulin-independeant, constitutively active enzyme. Constitutively active CaMKII appears poised to participate in disease pathways by catalyzing the phosphorylation of classes of protein targets important for excitation-contraction coupling and cell survival, including ion channels and Ca2+ homeostatic proteins, and transcription factors that drive hypertrophic and inflammatory gene expression. This rich diversity of downstream targets helps to explain the potential for CaMKII to simultaneously affect mechanical and electrical properties of heart muscle cells. Proof of concept studies from a growing number of investigators show that CaMKII inhibition is beneficial for improving myocardial performance and reducing arrhythmias. Here we review the molecular physiology of CaMKII, discuss CaMKII actions at key cellular targets and results of animal models of myocardial hypertrophy, dysfunction and arrhythmias that suggest CaMKII inhibition may benefit myocardial function while reducing arrhythmias. PMID:22679140

  14. IP3 stimulates CA++ efflux from fusogenic carrot protoplasts

    International Nuclear Information System (INIS)

    Rincon, M.; Boss, W.F.

    1986-01-01

    Polyphosphoinositide breakdown plays an important role in signal transduction in animal cells (Berridge and Irvine, 1984, Nature, 312:315). Upon stimulation, phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate to inositol 1,4,5-trisphosphate (IP 3 ) and diacylglycerol both of which act as cellular second messengers. IP 3 mobilizes Ca ++ from internal stores, hence the cytosolic free Ca ++ concentration increases and those physiological activities regulated by Ca ++ are stimulated. To test if plant cells also responded to IP 3 , Ca ++ efflux studies were done with fusogenic carrot protoplasts released in EGTA. The protoplasts were preloaded with 45 Ca ++ placed in a Ca ++ -free medium, and efflux determined as 45 Ca ++ loss from the protoplasts. IP 3 (10-20μM) caused enhanced 45 Ca ++ efflux and the response was sustained for at least 15 min. In plants, as in animals, the observed IP 3 -enhanced 45 Ca ++ efflux suggested that IP 3 released Ca ++ from internal stores, and the increased free cytosolic Ca ++ activated Ca ++ pumping mechanisms which restored the Ca ++ concentration in the cytosol to the normal level

  15. Determination of the calcium species in coal chars by Ca K-edge XANES analysis

    Science.gov (United States)

    Liu, Li-Juan; Liu, Hui-Jun; Cui, Ming-Qi; Hu, Yong-Feng; Zheng, Lei; Zhao, Yi-Dong; Ma, Chen-Yan; Xi, Shi-Bo; Yang, Dong-Liang; Guo, Zhi-Ying; Wang, Jie

    2013-02-01

    Ca-based additives have been widely used as a sulfur adsorbent during coal pyrolysis and gasification. The Ca speciation and evolution during the pyrolysis of coal with Ca additives have attracted great attention. In this paper, Ca species in the coal chars prepared from the pyrolysis of Ca(OH)2 or CaCO3-added coals are studied by using Ca K-edge X-ray absorption near-edge structural spectroscopy. The results demonstrate that Ca(OH)2, CaSO4, CaS and CaO coexist in the Ca(OH)2-added chars, while Ca(OH)2 and CaSO4 are the main species in the Ca(OH)2-added chars. Besides, a carboxyl-bound Ca is also formed during both the pyrolysis for the Ca(OH)2-added and the CaCO3-added coals. A detailed discussion about the Ca speciation is given.

  16. Selective reinnervation of hippocampal area CA1 and the fascia dentata after destruction of CA3-CA4 afferents with kainic acid.

    Science.gov (United States)

    Nadler, J V; Perry, B W; Cotman, C W

    1980-01-20

    Intraventricular injections of kainic acid were used to destroy the hippocampal CA3-CA4 cells, thus denervating the inner third of the molecular layer of the fascia dentata and stratum radiatum and stratum oriens of area CA1. The responses of intact afferents to such lesions were then examined histologically. The hippocampal mossy fibers densely reinnervated the inner portion of the dentate molecular layer after bilateral destruction of CA4 neurons and to a lesser extent after unilateral destruction. Septohippocampal fibers replaced CA4-derived fibers in the dentate molecular layer only after particularly extensive bilateral CA4 lesions. Medial perforant path fibers showed no anatomical response to any of these lesions. Neither septohippocampal, temporoammonic nor mossy fibers proliferated in or grew into the denervated laminae of area CA1. These results show a preferential ordering in the reinnervation of dentate granule cells which is not readily explained by proximity to the degenerating fibers and also that removal of CA3-CA4-derived innervation more readily elicits translaminar growth in the fascia dentata than in area CA1. These results may be relevant to clinical situations in which neurons of the hippocampal end-blade are lost.

  17. Characterization of Bacillus subtilis YfkE (ChaA): a calcium-specific Ca2+/H+ antiporter of the CaCA family.

    Science.gov (United States)

    Fujisawa, Makoto; Wada, Yuko; Tsuchiya, Takahiro; Ito, Masahiro

    2009-08-01

    YfkE, a protein from Bacillus subtilis, exhibits homology to the Ca(2+):Cation Antiporter (CaCA) Family. In a fluorescence-based assay of everted membrane vesicles prepared from Na(+)(Ca(2+))/H(+) antiporter-defective mutant Escherichia coli KNabc, YfkE exhibited robust Ca(2+)/H(+) antiport activity, with a K (m) for Ca(2+) estimated at 12.5 muM at pH 8.5 and 113 muM at pH 7.5. Neither Na(+) nor K(+) served as a substrate. Mg(2+) also did not serve as a substrate, but inhibited the Ca(2+)/H(+) antiporter activity. The Ca(2+) transport capability of YfkE was also observed directly by transport assays in everted membrane vesicles using radiolabeled (45)Ca(2+). Transcriptional analysis from the putative yfkED operon using beta-garactosidase activity as a reporter revealed that both of the yfkE and yfkD genes are regulated by forespore-specific sigma factor, SigG, and the general stress response regulator, SigB. These results suggest that YfkE may be needed for Ca(2+) signaling in the sporulation or germination process in B. subtilis. ChaA is proposed as the designation for YfkE of B. subtilis.

  18. Is tissue CA125 expression in epithelial ovarian adenocarcinoma heterogenic?

    DEFF Research Database (Denmark)

    Sparholt, Morten H; Høgdall, Claus K; Nedergaard, Lotte

    2013-01-01

    To evaluate if heterogeneity of tissue cancer antigen 125 (CA125) expression is present in epithelial serous adenocarcinomas. Furthermore, to investigate whether there is a correlation between levels of CA125 tissue expression, serum level of CA125, stage, and grade. A total of 10 patients...... diagnosed with serous ovarian adenocarcinomas were included. Preoperative blood samples were collected to determine serum CA125 levels. Tumor tissue from primary surgery was collected and processed for immunohistochemical analyses. CA125 was expressed in varying degrees in tumor tissues from all patients....... Mean tissue CA125 expression for each patient ranged from 36% to 98%. Intrapatient variations in tissue expression ranged from 10% to 90% point. No significant correlations between levels of CA125 tissue expression, serum level of CA125, stage, and grade were found. We found that the tissue expression...

  19. Store-operated Ca2+ entry is not required for fertilization-induced Ca2+ signaling in mouse eggs.

    Science.gov (United States)

    Bernhardt, Miranda L; Padilla-Banks, Elizabeth; Stein, Paula; Zhang, Yingpei; Williams, Carmen J

    2017-07-01

    Repetitive oscillations in cytoplasmic Ca 2+ due to periodic Ca 2+ release from the endoplasmic reticulum (ER) drive mammalian embryo development following fertilization. Influx of extracellular Ca 2+ to support the refilling of ER stores is required for sustained Ca 2+ oscillations, but the mechanisms underlying this Ca 2+ influx are controversial. Although store-operated Ca 2+ entry (SOCE) is an appealing candidate mechanism, several groups have arrived at contradictory conclusions regarding the importance of SOCE in oocytes and eggs. To definitively address this question, Ca 2+ influx was assessed in oocytes and eggs lacking the major components of SOCE, the ER Ca 2+ sensor STIM proteins, and the plasma membrane Ca 2+ channel ORAI1. We generated oocyte-specific conditional knockout (cKO) mice for Stim1 and Stim2, and also generated Stim1/2 double cKO mice. Females lacking one or both STIM proteins were fertile and their ovulated eggs displayed normal patterns of Ca 2+ oscillations following fertilization. In addition, no impairment was observed in ER Ca 2+ stores or Ca 2+ influx following store depletion. Similar studies were performed on eggs from mice globally lacking ORAI1; no abnormalities were observed. Furthermore, spontaneous Ca 2+ influx was normal in oocytes from Stim1/2 cKO and ORAI1-null mice. Finally, we tested if TRPM7-like channels could support spontaneous Ca 2+ influx, and found that it was largely prevented by NS8593, a TRPM7-specific inhibitor. Fertilization-induced Ca 2+ oscillations were also impaired by NS8593. Combined, these data robustly show that SOCE is not required to support appropriate Ca 2+ signaling in mouse oocytes and eggs, and that TRPM7-like channels may contribute to Ca 2+ influx that was previously attributed to SOCE. Published by Elsevier Ltd.

  20. MicroRNA-145 suppresses ROS-induced Ca{sup 2+} overload of cardiomyocytes by targeting CaMKIIδ

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Min-Ji [Cardiovascular Research Institute, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Jang, Jin-Kyung [College of Pharmacy, Sookmyung Women’s University, 52 HyoChangWon-Gil, Yongsan-ku, Seoul 140-742 (Korea, Republic of); Ham, Onju; Song, Byeong-Wook; Lee, Se-Yeon [Cardiovascular Research Institute, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Lee, Chang Yeon; Park, Jun-Hee [Department of Integrated Omics for Biomedical Sciences, Graduate School, Yonsei University, 50 Yonsei-ro, Seodamun-gu, Seoul 120-759 (Korea, Republic of); Lee, Jiyun; Seo, Hyang-Hee [Cardiovascular Research Institute, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Choi, Eunhyun [Severance Integrative Research Institute for Cerebral and Cardiovascular Disease, Yonsei University Health System, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Jeon, Woo-min [Department of Animal Resource, Sahmyook University, Seoul 139-742 (Korea, Republic of); Hwang, Hye Jin [Cardiovascular Research Institute, Yonsei University College of Medicine, 250 Seongsanno, Seodamun-gu, Seoul 120-752 (Korea, Republic of); Shin, Hyun-Taek [College of Pharmacy, Sookmyung Women’s University, 52 HyoChangWon-Gil, Yongsan-ku, Seoul 140-742 (Korea, Republic of); and others

    2013-06-14

    Highlights: •CaMKIIδ mediates H{sub 2}O{sub 2}-induced Ca{sup 2+} overload in cardiomyocytes. •miR-145 can inhibit Ca{sup 2+} overload. •A luciferase assay confirms that miR-145 functions as a CaMKIIδ-targeting miRNA. •Overexpression of miR-145 regulates CaMKIIδ-related genes and ameliorates apoptosis. -- Abstract: A change in intracellular free calcium (Ca{sup 2+}) is a common signaling mechanism of reperfusion-induced cardiomyocyte death. Calcium/calmodulin dependent protein kinase II (CaMKII) is a critical regulator of Ca{sup 2+} signaling and mediates signaling pathways responsible for functions in the heart including hypertrophy, apoptosis, arrhythmia, and heart disease. MicroRNAs (miRNA) are involved in the regulation of cell response, including survival, proliferation, apoptosis, and development. However, the roles of miRNAs in Ca{sup 2+}-mediated apoptosis of cardiomyocytes are uncertain. Here, we determined the potential role of miRNA in the regulation of CaMKII dependent apoptosis and explored its underlying mechanism. To determine the potential roles of miRNAs in H{sub 2}O{sub 2}-mediated Ca{sup 2+} overload, we selected and tested 6 putative miRNAs that targeted CaMKIIδ, and showed that miR-145 represses CaMKIIδ protein expression and Ca{sup 2+} overload. We confirmed CaMKIIδ as a direct downstream target of miR-145. Furthermore, miR-145 regulates Ca{sup 2+}-related signals and ameliorates apoptosis. This study demonstrates that miR-145 regulates reactive oxygen species (ROS)-induced Ca{sup 2+} overload in cardiomyocytes. Thus, miR-145 affects ROS-mediated gene regulation and cellular injury responses.

  1. Caffeine- and ryanodine-sensitive Ca(2+)-induced Ca2+ release from the endoplasmic reticulum in honeybee photoreceptors.

    Science.gov (United States)

    Walz, B; Baumann, O; Zimmermann, B; Ciriacy-Wantrup, E V

    1995-04-01

    Light stimulation of invertebrate microvillar photoreceptors causes a large rapid elevation in Cai, shown previously to modulate the adaptational state of the cells. Cai rises, at least in part, as a result of Ins(1,4,5)P3-induced Ca2+ release from the submicrovillar endoplasmic reticulum (ER). Here, we provide evidence for Ca(2+)-induced Ca2+ release (CICR) in an insect photoreceptor. In situ microphotometric measurements of Ca2+ fluxes across the ER membrane in permeabilized slices of drone bee retina show that (a) caffeine induces Ca2+ release from the ER; (b) caffeine and Ins(1,4,5)P3 open distinct Ca2+ release pathways because only caffeine-induced Ca2+ release is ryanodine sensitive and heparin insensitive, and because caffeine and Ins(1,4,5)P3 have additive effects on the rate of Ca2+ release; (c) Ca2+ itself stimulates release of Ca2+ via a ryanodine-sensitive pathway; and (d) cADPR is ineffective in releasing Ca2+. Microfluorometric intracellular Ca2+ measurements with fluo-3 indicate that caffeine induces a persistent elevation in Cai. Electrophysiological recordings demonstrate that caffeine mimics all aspects of Ca(2+)-mediated facilitation and adaptation in drone photoreceptors. We conclude that the ER in drone photoreceptors contains, in addition to the Ins(1,4,5)P3-sensitive release pathway, a CICR pathway that meets key pharmacological criteria for a ryanodine receptor. Coexpression of both release mechanisms could be required for the production of rapid light-induced Ca2+ elevations, because Ca2+ amplifies its own release through both pathways by a positive feedback. CICR may also mediate the spatial spread of Ca2+ release from the submicrovillar ER toward more remote ER subregions, thereby activating Ca(2+)-sensitive cell processes that are not directly involved in phototransduction.

  2. Modeling CaMKII-mediated regulation of L-type Ca2+ channels and ryanodine receptors in the heart

    Directory of Open Access Journals (Sweden)

    Joseph L Greenstein

    2014-04-01

    Full Text Available Excitation-contraction coupling (ECC in the cardiac myocyte is mediated by a number of highly integrated mechanisms of intracellular Ca2+ transport. Voltage- and Ca2+-dependent L-type Ca2+ channels (LCCs allow for Ca2+ entry into the myocyte, which then binds to nearby ryanodine receptors (RyRs and triggers Ca2+ release from the sarcoplasmic reticulum in a process known as Ca2+-induced Ca2+ release. The highly coordinated Ca2+-mediated interaction between LCCs and RyRs is further regulated by the cardiac isoform of the Ca2+/calmodulin-dependent protein kinase (CaMKII. Because CaMKII targets and modulates the function of many ECC proteins, elucidation of its role in ECC and integrative cellular function is challenging and much insight has been gained through the use of detailed computational models. Multiscale models that can both reconstruct the detailed nature of local signaling events within the cardiac dyad and predict their functional consequences at the level of the whole cell have played an important role in advancing our understanding of CaMKII function in ECC. Here, we review experimentally based models of CaMKII function with a focus on LCC and RyR regulation, and the mechanistic insights that have been gained through their application.

  3. New anticancer drug candidates sulfonamides as selective hCA IX or hCA XII inhibitors.

    Science.gov (United States)

    Gul, Halise Inci; Yamali, Cem; Sakagami, Hiroshi; Angeli, Andrea; Leitans, Janis; Kazaks, Andris; Tars, Kaspars; Ozgun, Dilan Ozmen; Supuran, Claudiu T

    2018-04-01

    In this study, new 4-[3-(aryl)-5-substitutedphenyl-4,5-dihydro-1H-pyrazole-1-yl]benzensulfonamides (19-36) were synthesized and evaluated their cytotoxic/anticancer and CA inhibitory effects. According to results obtained, the compounds 34 (4-[5-(2,3,4-trimethoxyphenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole-1-yl] benzensulfonamide, Potency-Selectivity Expression (PSE) = 141) and 36 (4-[5-(3,4,5-trimethoxyphenyl)-3-(thiophen-2-yl)-4,5-dihydro-1H-pyrazole-1-yl]benzensulfonamide, PSE = 54.5) were found the leader anticancer compounds with the highest PSE values. In CA inhibitory studies, the compounds 36 and 24 (4-[5-(3,4,5-trimethoxyphenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-yl]benzensulfonamide) were found the leader CA inhibitors depending on selectivity ratios. The compound 36 was a selective inhibitor of hCA XII isoenzyme (hCA I/hCA XII = 1250 and hCA II/hCA XII = 224) while the compound 24 was a selective inhibitor of hCA IX isoenzyme (hCA I/hCA IX = 161 and hCA II/hCA IX = 177). The compounds 24, 34, and 36 can be considered to develop new anticancer drug candidates. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Sensing mechanisms involved in Ca2+ and Mg2+ homeostasis

    NARCIS (Netherlands)

    Ferre, S.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2012-01-01

    Calcium (Ca(2+)) and magnesium (Mg(2+)) ions are involved in many vital physiological functions. In the human body, Ca(2+) and Mg(2+) homeostatic systems rely on three components: (i) tissues (re)absorbing or storing Ca(2+) and Mg(2+), mainly kidney, intestine, and bone; (ii) hormones that modulate

  5. Electronic structure of Ca, Sr, and Ba under pressure.

    Science.gov (United States)

    Animalu, A. O. E.; Heine, V.; Vasvari, B.

    1967-01-01

    Electronic band structure calculations phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure

  6. Enhanced sarcoplasmic reticulum Ca(2+) release following intermittent sprint training

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Lunde, Per; Levin, Kasper

    2000-01-01

    -977) arbitrary units Ca(2+). g protein(-1). min(-1) (after). The relative SR density of functional ryanodine receptors (RyR) remained unchanged after training; there was, however, a 48% (P RyR. No significant differences in Ca(2+) uptake rate and Ca(2+)-ATPase capacity were...

  7. Registration of CA0469C025C chickpea germplasm

    Science.gov (United States)

    Chickpea (Cicer arientinum L.) germplasm CA0469C025C (Reg. No. XXX; PI XXX), was released by the USDA-ARS in 2010. CA0469C025C was released based on its improved yield and reaction to Ascochyta blight relative to the popular commercial cultivars ‘Dwelley’, ‘Sierra’, and ‘Sawyer’. CA0490C025C is deri...

  8. Integrated Mechanisms of CaMKII-dependent ventricular remodeling

    Directory of Open Access Journals (Sweden)

    Michael M Kreusser

    2014-03-01

    Full Text Available CaMKII has been shown to be activated during different cardiac pathological processes, and CaMKII-dependent mechanisms contribute to pathological cardiac remodeling, cardiac arrhythmias and contractile dysfunction during heart failure. Activation of CaMKII during cardiac stress results in a broad number of biological effects such as, on the one hand, acute effects due to phosphorylation of distinct cellular proteins as ion channels and calcium handling proteins and, on the other hand, integrative mechanisms by changing gene expression. This review focuses on transcriptional and epigenetic effects of CaMKII activation during chronic cardiac remodeling. Multiple mechanisms have been described how CaMKII mediates changes in cardiac gene expression. CaMKII has been shown to directly phosphorylate components of the cardiac gene regulation machinery. CaMKII phosphorylates several transcription factors such as CREB that induces the activation of specific gene programs. CaMKII activates transcriptional regulators also indirectly by phosphorylating histone deacetylases, especially HDAC4, which in turn inhibits transcription factors that drive cardiac hypertrophy, fibrosis and dysfunction. Recent studies demonstrate that CaMKII also phosphorylate directly histones, which may contribute to changes in gene expression. These findings of CaMKII-dependent gene regulation during cardiac remodeling processes suggest novel strategies for CaMKII-dependent transcriptional or epigenetic therapies to control cardiac gene expression and function. Manipulation of CaMKII-dependent signaling pathways in the settings of pathological cardiac growth, remodeling, and heart failure represents an auspicious therapeutic approach.

  9. High-capacity Ca2+ binding of human skeletal calsequestrin.

    Science.gov (United States)

    Sanchez, Emiliano J; Lewis, Kevin M; Danna, Benjamin R; Kang, Chulhee

    2012-03-30

    Calsequestrin, the major calcium storage protein in both cardiac and skeletal muscle, binds large amounts of Ca(2+) in the sarcoplasmic reticulum and releases them during muscle contraction. For the first time, the crystal structures of Ca(2+) complexes for both human (hCASQ1) and rabbit (rCASQ1) skeletal calsequestrin were determined, clearly defining their Ca(2+) sequestration capabilities through resolution of high- and low-affinity Ca(2+)-binding sites. rCASQ1 crystallized in low CaCl(2) buffer reveals three high-affinity Ca(2+) sites with trigonal bipyramidal, octahedral, and pentagonal bipyramidal coordination geometries, along with three low-affinity Ca(2+) sites. hCASQ1 crystallized in high CaCl(2) shows 15 Ca(2+) ions, including the six Ca(2+) ions in rCASQ1. Most of the low-affinity sites, some of which are μ-carboxylate-bridged, are established by the rotation of dimer interfaces, indicating cooperative Ca(2+) binding that is consistent with our atomic absorption spectroscopic data. On the basis of these findings, we propose a mechanism for the observed in vitro and in vivo dynamic high-capacity and low-affinity Ca(2+)-binding activity of calsequestrin.

  10. High-capacity Ca2+ Binding of Human Skeletal Calsequestrin*

    Science.gov (United States)

    Sanchez, Emiliano J.; Lewis, Kevin M.; Danna, Benjamin R.; Kang, ChulHee

    2012-01-01

    Calsequestrin, the major calcium storage protein in both cardiac and skeletal muscle, binds large amounts of Ca2+ in the sarcoplasmic reticulum and releases them during muscle contraction. For the first time, the crystal structures of Ca2+ complexes for both human (hCASQ1) and rabbit (rCASQ1) skeletal calsequestrin were determined, clearly defining their Ca2+ sequestration capabilities through resolution of high- and low-affinity Ca2+-binding sites. rCASQ1 crystallized in low CaCl2 buffer reveals three high-affinity Ca2+ sites with trigonal bipyramidal, octahedral, and pentagonal bipyramidal coordination geometries, along with three low-affinity Ca2+ sites. hCASQ1 crystallized in high CaCl2 shows 15 Ca2+ ions, including the six Ca2+ ions in rCASQ1. Most of the low-affinity sites, some of which are μ-carboxylate-bridged, are established by the rotation of dimer interfaces, indicating cooperative Ca2+ binding that is consistent with our atomic absorption spectroscopic data. On the basis of these findings, we propose a mechanism for the observed in vitro and in vivo dynamic high-capacity and low-affinity Ca2+-binding activity of calsequestrin. PMID:22337878

  11. Significance of the tumor markers CA 125 and CA 15-3 in postoperative diagnosis of ovarian and breast cancer

    International Nuclear Information System (INIS)

    Johannsen, B.; Bartel, U.; Elling, D.

    1989-01-01

    In 271 patients with ovarian carcinoma, benign ovarian tumors, breast cancer, and two control groups, serum levels of CA 125, CA 15-3, CEA and, partly, CA 19-9 were determined immunoradiometrically. According to the results of the determination of CA 125 in the follow-up of ovarian carcinoma, CA 125 represents a useful marker for early detection of recurrences, especially in cases of diffuse carcinoma dissemination. In incomplete tumor debulking, postoperative CA 125 serum levels did not prove to be helpful except that a positive level renders invasive diagnostic investigation no longer necessary. Postoperative follow-up in breast cancer early reveals distant metastases, with very high levels in patients with bone metastases. By simultaneous measurement of CA 15-3 and CEA the sensitivity could be increased from 86% (CA 15-3 only) to 93%. (author)

  12. Chemical purification of CaCO{sub 3} and CaWO{sub 4} powders used for CaWO{sub 4} crystal production for the CRESST experiment

    Energy Technology Data Exchange (ETDEWEB)

    Trinh Thi, H.H.; Defay, X.; Erb, A.; Hampf, R.; Lanfranchi, J.C.; Langenkaemper, A.; Morgalyuk, V.; Muenster, A.; Mondragon, E.; Oppenheimer, C.; Potzel, W.; Schoenert, S.; Steiger, H.; Ulrich, A.; Wawoczny, S.; Willers, M.; Zoeller, A. [Physik-Department and Excellence Cluster Universe, Technische Universitaet Muenchen, Garching (Germany)

    2016-07-01

    CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) uses CaWO{sub 4} single crystals as targets for the direct search for dark matter particles. Since several years these CaWO{sub 4} crystals are grown at the Technische Universitaet Muenchen. Thereby, commercially available CaCO{sub 3} and WO{sub 3} powders are used for the synthesis of CaWO{sub 4} powder. For the experiment low intrinsic contaminations of the crystals play a crucial role. In order to improve the radiopurity of the crystals it is necessary to reduce potential sources for radioactive backgrounds such as U and Th. In this poster we will present our studies of the chemical purification of the CaCO{sub 3} and CaWO{sub 4} powders.

  13. Mechanics of Old Faithful Geyser, Calistoga, CA

    Science.gov (United States)

    Rudolph, M.L.; Manga, M.; Hurwitz, Shaul; Johnston, Malcolm J.; Karlstrom, L.; Wang, Chun-Yong

    2012-01-01

    In order to probe the subsurface dynamics associated with geyser eruptions, we measured ground deformation at Old Faithful Geyser of Calistoga, CA. We present a physical model in which recharge during the period preceding an eruption is driven by pressure differences relative to the aquifer supplying the geyser. The model predicts that pressure and ground deformation are characterized by an exponential function of time, consistent with our observations. The geyser's conduit is connected to a reservoir at a depth of at least 42 m, and pressure changes in the reservoir can produce the observed ground deformations through either a poroelastic or elastic mechanical model.

  14. Tumor markers CA19-9, CA242 and CEA in the diagnosis of pancreatic cancer: a meta-analysis.

    Science.gov (United States)

    Zhang, Yimin; Yang, Jun; Li, Hongjuan; Wu, Yihua; Zhang, Honghe; Chen, Wenhu

    2015-01-01

    Pancreatic cancer has the worst prognosis and early detection is crucial for improving patient prognosis. Therefore, we performed a meta-analysis to evaluate and compare the sensitivity and specificity of single test of CA19-9, CA242, and CEA, as well as combination test in pancreatic cancer detection. We searched PubMed, Embase, Medline, and Wanfang databases for studies that evaluated the diagnostic validity of CA19-9, CA242, and CEA between January 1990 and September 2014. Data were analyzed by Meta-Disc and STATA software. A total of 21 studies including 3497 participants, which fulfilled the inclusion criteria were considered for analysis. The pooled sensitivities for CA19-9, CA242, and CEA were 75.4 (95% CI: 73.4-77.4), 67.8 (95% CI: 65.5-70), and 39.5 (95% CI: 37.3-41.7), respectively. The pooled specificities of CA19-9, CA242, and CEA were 77.6 (95% CI: 75.4-79.7), 83 (95% CI: 81-85), and 81.3 (95% CI: 79.3-83.2), respectively. Parallel combination of CA19-9+CA242 has a higher sensitivity (89, 95% CI: 80-95) without impairing the specificity (75, 95% CI: 67-82). Our meta-analysis showed that CA242 and CA19-9 have better performance in the diagnosis of pancreatic cancer than CEA. Furthermore, parallel combination test of CA19-9+CA242 could be of better diagnostic value than individual CA242 or CA19-9 test.

  15. Caffeine- and ryanodine-sensitive Ca(2+)-induced Ca2+ release from the endoplasmic reticulum in honeybee photoreceptors

    OpenAIRE

    1995-01-01

    Light stimulation of invertebrate microvillar photoreceptors causes a large rapid elevation in Cai, shown previously to modulate the adaptational state of the cells. Cai rises, at least in part, as a result of Ins(1,4,5)P3-induced Ca2+ release from the submicrovillar endoplasmic reticulum (ER). Here, we provide evidence for Ca(2+)- induced Ca2+ release (CICR) in an insect photoreceptor. In situ microphotometric measurements of Ca2+ fluxes across the ER membrane in permeabilized slices of dron...

  16. The other side of cardiac Ca2+ signaling: transcriptional control

    Directory of Open Access Journals (Sweden)

    Alejandro eDomínguez-Rodríquez

    2012-11-01

    Full Text Available Ca2+ is probably the most versatile signal transduction element used by all cell types. In the heart, it is essential to activate cellular contraction in each heartbeat. Nevertheless Ca2+ is not only a key element in excitation-contraction coupling (EC coupling, but it is also a pivotal second messenger in cardiac signal transduction, being able to control processes such as excitability, metabolism, and transcriptional regulation. Regarding the latter, Ca2+ activates Ca2+-dependent transcription factors by a process called excitation-transcription coupling (ET coupling. ET coupling is an integrated process by which the common signaling pathways that regulate EC coupling activate transcription factors. Although ET coupling has been extensively studied in neurons and other cell types, less is known in cardiac muscle. Some hints have been found in studies on the development of cardiac hypertrophy, where two Ca2+-dependent enzymes are key actors: Ca2+/Calmodulin kinase II (CaMKII and phosphatase calcineurin, both of which are activated by the complex Ca2+/ /Calmodulin. The question now is how ET coupling occurs in cardiomyocytes, where intracellular Ca2+ is continuously oscillating. In this focused review, we will draw attention to location of Ca2+ signaling: intranuclear ([Ca2+]n or cytoplasmic ([Ca2+]c, and the specific ionic channels involved in the activation of cardiac ET coupling. Specifically, we will highlight the role of the 1,4,5 inositol triphosphate receptors (IP3Rs in the elevation of [Ca2+]n levels, which are important to locally activate CaMKII, and the role of transient receptor potential channels canonical (TRPCs in [Ca2+]c, needed to activate calcineurin.

  17. Elementary properties of CaV1.3 Ca(2+) channels expressed in mouse cochlear inner hair cells.

    Science.gov (United States)

    Zampini, Valeria; Johnson, Stuart L; Franz, Christoph; Lawrence, Neil D; Münkner, Stefan; Engel, Jutta; Knipper, Marlies; Magistretti, Jacopo; Masetto, Sergio; Marcotti, Walter

    2010-01-01

    Mammalian cochlear inner hair cells (IHCs) are specialized to process developmental signals during immature stages and sound stimuli in adult animals. These signals are conveyed onto auditory afferent nerve fibres. Neurotransmitter release at IHC ribbon synapses is controlled by L-type Ca(V)1.3 Ca(2+) channels, the biophysics of which are still unknown in native mammalian cells. We have investigated the localization and elementary properties of Ca(2+) channels in immature mouse IHCs under near-physiological recording conditions. Ca(V)1.3 Ca(2+) channels at the cell pre-synaptic site co-localize with about half of the total number of ribbons present in immature IHCs. These channels activated at about 70 mV, showed a relatively short first latency and weak inactivation, which would allow IHCs to generate and accurately encode spontaneous Ca(2+) action potential activity characteristic of these immature cells. The Ca(V)1.3 Ca(2+) channels showed a very low open probability (about 0.15 at 20 mV: near the peak of an action potential). Comparison of elementary and macroscopic Ca(2+) currents indicated that very few Ca(2+) channels are associated with each docked vesicle at IHC ribbon synapses. Finally, we found that the open probability of Ca(2+) channels, but not their opening time, was voltage dependent. This finding provides a possible correlation between presynaptic Ca(2+) channel properties and the characteristic frequency/amplitude of EPSCs in auditory afferent fibres.

  18. Variability of Mg/Ca and Sr/Ca between and within the planktonic foraminifers Globigerina bulloides and Globorotalia truncatulinoides

    NARCIS (Netherlands)

    Anand-Jha, P.; Elderfield, H.

    2005-01-01

    The variability in Mg/Ca and Sr/Ca within individual tests and chambers of tests, and samples consisting of differing numbers of individuals, was determined for Globigerina bulloides and Globorotalia truncatulinoides in a North Atlantic core top sample (52.918°N 16.917°W'). The variability in Mg/Ca

  19. Predictors of pretreatment CA125 at ovarian cancer diagnosis

    DEFF Research Database (Denmark)

    Babic, Ana; Cramer, Daniel W; Kelemen, Linda E

    2017-01-01

    in CA125 between studies and linear regression to estimate the association between epidemiologic factors and tumor characteristics and pretreatment CA125 levels. RESULTS: In age-adjusted models, older age, history of pregnancy, history of tubal ligation, family history of breast cancer, and family...... history of ovarian cancer were associated with higher CA125 levels while endometriosis was associated with lower CA125 levels. After adjusting for tumor-related characteristics (stage, histology, grade), body mass index (BMI) higher than 30 kg/m2was associated with 10% (95% CI 2, 19%) higher CA125 levels...

  20. P and Ca requirements for Japanese quail.

    Science.gov (United States)

    Mariz, C B L; Silva, J H V; Filho, J J; Lima, M R; Costa, F G P

    2017-04-01

    Four experiments were conducted to estimate the phosphorus and calcium requirements for weight maintenance and weight gain in Japanese quails during their growth phase from 16 to 36 days. Japanese quails aged 16 days were used for estimating the phosphorous and calcium requirements for weight maintenance or weight gain, with these quails composing each reference slaughter group and the others distributed in a completely randomized design, housed in cages of galvanized wire (33 × 33 × 16 cm) that were stored in acclimatized chambers with specific environmental temperatures. The light programme used during the 20-day experimental period was 24 h of artificial light. Analysis of the data showed that the prediction equations for estimating the phosphorus and calcium requirements for weight maintenance and weight gain of Japanese quails between 16 and 36 days of age were P (g/quail/day) = P 0.75 *(9.3695 + 7.7397*T) + 9.70*WG, in which P is the phosphorus requirement, and Ca (g/quail/day) = P 0.75 *(363.99 - 8.0262*T) + 28.15*WG, in which Ca is the calcium requirement, P is BW (kg), T is temperature (°C) and WG (g/quail/day). Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  1. Klotho regulates CA1 hippocampal synaptic plasticity.

    Science.gov (United States)

    Li, Qin; Vo, Hai T; Wang, Jing; Fox-Quick, Stephanie; Dobrunz, Lynn E; King, Gwendalyn D

    2017-04-07

    Global klotho overexpression extends lifespan while global klotho-deficiency shortens it. As well, klotho protein manipulations inversely regulate cognitive function. Mice without klotho develop rapid onset cognitive impairment before they are 2months old. Meanwhile, adult mice overexpressing klotho show enhanced cognitive function, particularly in hippocampal-dependent tasks. The cognitive enhancing effects of klotho extend to humans with a klotho polymorphism that increases circulating klotho and executive function. To affect cognitive function, klotho could act in or on the synapse to modulate synaptic transmission or plasticity. However, it is not yet known if klotho is located at synapses, and little is known about its effects on synaptic function. To test this, we fractionated hippocampi and detected klotho expression in both pre and post-synaptic compartments. We find that loss of klotho enhances both pre and post-synaptic measures of CA1 hippocampal synaptic plasticity at 5weeks of age. However, a rapid loss of synaptic enhancement occurs such that by 7weeks, when mice are cognitively impaired, there is no difference from wild-type controls. Klotho overexpressing mice show no early life effects on synaptic plasticity, but decreased CA1 hippocampal long-term potentiation was measured at 6months of age. Together these data suggest that klotho affects cognition, at least in part, by regulating hippocampal synaptic plasticity. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. New fluorescent reagents specific for Ca2+-binding proteins

    International Nuclear Information System (INIS)

    Ben-Hail, Danya; Lemelson, Daniela; Israelson, Adrian; Shoshan-Barmatz, Varda

    2012-01-01

    Highlights: ► New reagents specifically inhibit the activity of Ca 2+ -dependent proteins. ► FITC-Ru and EITC-Ru allow for mechanism-independent probing of Ca 2+ -binding proteins. ► Changes in reagents fluorescence allow characterization of protein Ca 2+ -binding properties. -- Abstract: Ca 2+ carries information pivotal to cell life and death via its interactions with specific binding sites in a protein. We previously developed a novel photoreactive reagent, azido ruthenium (AzRu), which strongly inhibits Ca 2+ -dependent activities. Here, we synthesized new fluorescent ruthenium-based reagents containing FITC or EITC, FITC-Ru and EITC-Ru. These reagents were purified, characterized and found to specifically interact with and markedly inhibit Ca 2+ -dependent activities but not the activity of Ca 2+ -independent reactions. In contrast to many reagents that serve as probes for Ca 2+ , FITC-Ru and EITC-Ru are the first fluorescent divalent cation analogs to be synthesized and characterized that specifically bind to Ca 2+ -binding proteins and inhibit their activity. Such reagents will assist in characterizing Ca 2+ -binding proteins, thereby facilitating better understanding of the function of Ca 2+ as a key bio-regulator.

  3. Chronic Loss of CA2 Transmission Leads to Hippocampal Hyperexcitability.

    Science.gov (United States)

    Boehringer, Roman; Polygalov, Denis; Huang, Arthur J Y; Middleton, Steven J; Robert, Vincent; Wintzer, Marie E; Piskorowski, Rebecca A; Chevaleyre, Vivien; McHugh, Thomas J

    2017-05-03

    Hippocampal CA2 pyramidal cells project into both the neighboring CA1 and CA3 subfields, leaving them well positioned to influence network physiology and information processing for memory and space. While recent work has suggested unique roles for CA2, including encoding position during immobility and generating ripple oscillations, an interventional examination of the integrative functions of these connections has yet to be reported. Here we demonstrate that CA2 recruits feedforward inhibition in CA3 and that chronic genetically engineered shutdown of CA2-pyramidal-cell synaptic transmission consequently results in increased excitability of the recurrent CA3 network. In behaving mice, this led to spatially triggered episodes of network-wide hyperexcitability during exploration accompanied by the emergence of high-frequency discharges during rest. These findings reveal CA2 as a regulator of network processing in hippocampus and suggest that CA2-mediated inhibition in CA3 plays a key role in establishing the dynamic excitatory and inhibitory balance required for proper network function. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. CA-125 in Disease Progression and Treatment of Lymphangioleiomyomatosis.

    Science.gov (United States)

    Glasgow, Connie G; Pacheco-Rodriguez, Gustavo; Steagall, Wendy K; Haughey, Mary E; Julien-Williams, Patricia A; Stylianou, Mario P; Gochuico, Bernadette R; Moss, Joel

    2018-02-01

    Lymphangioleiomyomatosis (LAM) is a destructive lung disease of women caused by proliferation of neoplastic-like LAM cells, with mutations in the TSC1/2 tumor suppressor genes. Based on case reports, levels of cancer antigen 125 (CA-125), an ovarian cancer biomarker, can be elevated in patients with LAM. We hypothesized that elevated serum CA-125 levels seen in some patients with LAM were due to LAM, not other malignancies, and might respond to sirolimus treatment. Serum CA-125 levels were measured for 241 patients at each visit. Medical records were reviewed for co-morbidities, disease progression, and response to sirolimus treatment. CA-125 expression in LAM cells was determined by using immunohistochemical analysis. Almost 25% of patients with LAM had at least one elevated serum CA-125 measurement. Higher serum CA-125 levels correlated with lower FEV 1 , premenopausal status, and pleural effusion in a multivariate model (each P CA-125 levels decreased following sirolimus treatment (P = .002). CA-125 and α-smooth muscle actin were co-expressed in LAM lung nodules. Higher serum CA-125 levels were associated with pleural effusions and reduced pulmonary function and were decreased with sirolimus therapy. LAM cells express CA-125. Some elevated serum CA-125 levels may reflect serosal membrane involvement. Copyright © 2017. Published by Elsevier Inc.

  5. Spectral components of cytosolic [Ca2+] spiking in neurons

    DEFF Research Database (Denmark)

    Kardos, J; Szilágyi, N; Juhász, G

    1998-01-01

    We show here, by means of evolutionary spectral analysis and synthesis of cytosolic Ca2+ ([Ca2+]c) spiking observed at the single cell level using digital imaging fluorescence microscopy of fura-2-loaded mouse cerebellar granule cells in culture, that [Ca2+]c spiking can be resolved into evolutio......We show here, by means of evolutionary spectral analysis and synthesis of cytosolic Ca2+ ([Ca2+]c) spiking observed at the single cell level using digital imaging fluorescence microscopy of fura-2-loaded mouse cerebellar granule cells in culture, that [Ca2+]c spiking can be resolved...... into evolutionary spectra of a characteristic set of frequencies. Non-delayed small spikes on top of sustained [Ca2+]c were synthesized by a main component frequency, 0.132+/-0.012 Hz, showing its maximal amplitude in phase with the start of depolarization (25 mM KCI) combined with caffeine (10 mM) application...

  6. Preparation of Heterogeneous CaO Catalysts for Biodiesel Production

    Science.gov (United States)

    Widayat, W.; Darmawan, T.; Hadiyanto, H.; Rosyid, R. Ar

    2017-07-01

    The objective of this research was to develop heterogeneous catalysts from three CaO sources for biodiesel synthesis. The CaO catalyst were prepared from limestone, calcium hydroxide and calciun carbonate with thermal processing in a muffle furnace at 900°C.. The results showed that CaO catalyst from limestone has better characteristic than catalyst from Calcium Hydroxide and Calcium Carbonate. From morphology testing, the CaO catalyst derived from limestone formed a crystal, while The X-ray difraction analysis showed that the amount of CaO contained in limestone was the highest among the others. The yield of biodiesel obtained from the experiment was 89.98% for the catalyst from limestone; 85.15% for the catalyst Ca (OH)2; and 78.71% for CaCO3 catalyst.

  7. Spectroscopy of neutron-deficient nuclei around 36Ca

    International Nuclear Information System (INIS)

    Buerger, A.; Stanoiu, M.; Azaiez, F.; Bourgeois, Ch.; Franchoo, S.; Ibrahim, F.; Verney, D.; Dombradi, Zs.; Algora, A.; Fueloep, Zs.; Sohler, D.; Al-Khatib, A.; Bringel, P.; Engelhardt, C.; Huebel, H.; Bastin, B.; Benzoni, G.; Borcea, R.; Rotaru, F.; Sorlin, O.

    2006-01-01

    An experiment was performed to extend the knowledge of excited states in neutron-deficient Ca isotopes. In particular, excited states in 36Ca were searched for to allow for a comparison with its stable mirror nucleus, 36S. Secondary beams of 37Ca and 36Ca were produced by fragmentation of a primary 40Ca beam with an energy of 95 · A MeV on the SISSI target at GANIL. A variety of nuclei around 36Ca has been produced in a secondary Be target by neutron and proton-removal at beam energies around 61 · A MeV. The produced nuclei were identified using the spectrometer SPEG, and prompt γ rays were measured with the Chateau de Cristal. A preliminary value for the energy of the first 2+ state of 36Ca has been determined

  8. Structure of the CaMKIIdelta/calmodulin complex reveals the molecular mechanism of CaMKII kinase activation.

    Directory of Open Access Journals (Sweden)

    Peter Rellos

    2010-07-01

    Full Text Available Long-term potentiation (LTP, a long-lasting enhancement in communication between neurons, is considered to be the major cellular mechanism underlying learning and memory. LTP triggers high-frequency calcium pulses that result in the activation of Calcium/Calmodulin (CaM-dependent kinase II (CaMKII. CaMKII acts as a molecular switch because it remains active for a long time after the return to basal calcium levels, which is a unique property required for CaMKII function. Here we describe the crystal structure of the human CaMKIIdelta/Ca2+/CaM complex, structures of all four human CaMKII catalytic domains in their autoinhibited states, as well as structures of human CaMKII oligomerization domains in their tetradecameric and physiological dodecameric states. All four autoinhibited human CaMKIIs were monomeric in the determined crystal structures but associated weakly in solution. In the CaMKIIdelta/Ca2+/CaM complex, the inhibitory region adopted an extended conformation and interacted with an adjacent catalytic domain positioning T287 into the active site of the interacting protomer. Comparisons with autoinhibited CaMKII structures showed that binding of calmodulin leads to the rearrangement of residues in the active site to a conformation suitable for ATP binding and to the closure of the binding groove for the autoinhibitory helix by helix alphaD. The structural data, together with biophysical interaction studies, reveals the mechanism of CaMKII activation by calmodulin and explains many of the unique regulatory properties of these two essential signaling molecules.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3-D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the Web plugin are available in Text S1.

  9. Synaptic NMDA Receptor-Dependent Ca2+ Entry Drives Membrane Potential and Ca2+ Oscillations in Spinal Ventral Horn Neurons

    Science.gov (United States)

    Alpert, Michael H.; Alford, Simon

    2013-01-01

    During vertebrate locomotion, spinal neurons act as oscillators when initiated by glutamate release from descending systems. Activation of NMDA receptors initiates Ca2+-mediated intrinsic membrane potential oscillations in central pattern generator (CPG) neurons. NMDA receptor-dependent intrinsic oscillations require Ca2+-dependent K+ (KCa2) channels for burst termination. However, the location of Ca2+ entry mediating KCa2 channel activation, and type of Ca2+ channel – which includes NMDA receptors and voltage-gated Ca2+ channels (VGCCs) – remains elusive. NMDA receptor-dependent Ca2+ entry necessitates presynaptic release of glutamate, implying a location at active synapses within dendrites, whereas VGCC-dependent Ca2+ entry is not similarly constrained. Where Ca2+ enters relative to KCa2 channels is crucial to information processing of synaptic inputs necessary to coordinate locomotion. We demonstrate that Ca2+ permeating NMDA receptors is the dominant source of Ca2+ during NMDA-dependent oscillations in lamprey spinal neurons. This Ca2+ entry is synaptically located, NMDA receptor-dependent, and sufficient to activate KCa2 channels at excitatory interneuron synapses onto other CPG neurons. Selective blockade of VGCCs reduces whole-cell Ca2+ entry but leaves membrane potential and Ca2+ oscillations unaffected. Furthermore, repetitive oscillations are prevented by fast, but not slow, Ca2+ chelation. Taken together, these results demonstrate that KCa2 channels are closely located to NMDA receptor-dependent Ca2+ entry. The close spatial relationship between NMDA receptors and KCa2 channels provides an intrinsic mechanism whereby synaptic excitation both excites and subsequently inhibits ventral horn neurons of the spinal motor system. This places the components necessary for oscillation generation, and hence locomotion, at glutamatergic synapses. PMID:23646190

  10. Mitochondria Maintain Distinct Ca2+Pools in Cone Photoreceptors.

    Science.gov (United States)

    Giarmarco, Michelle M; Cleghorn, Whitney M; Sloat, Stephanie R; Hurley, James B; Brockerhoff, Susan E

    2017-02-22

    Ca 2+ ions have distinct roles in the outer segment, cell body, and synaptic terminal of photoreceptors. We tested the hypothesis that distinct Ca 2+ domains are maintained by Ca 2+ uptake into mitochondria. Serial block face scanning electron microscopy of zebrafish cones revealed that nearly 100 mitochondria cluster at the apical side of the inner segment, directly below the outer segment. The endoplasmic reticulum surrounds the basal and lateral surfaces of this cluster, but does not reach the apical surface or penetrate into the cluster. Using genetically encoded Ca 2+ sensors, we found that mitochondria take up Ca 2+ when it accumulates either in the cone cell body or outer segment. Blocking mitochondrial Ca 2+ uniporter activity compromises the ability of mitochondria to maintain distinct Ca 2+ domains. Together, our findings indicate that mitochondria can modulate subcellular functional specialization in photoreceptors. SIGNIFICANCE STATEMENT Ca 2+ homeostasis is essential for the survival and function of retinal photoreceptors. Separate pools of Ca 2+ regulate phototransduction in the outer segment, metabolism in the cell body, and neurotransmitter release at the synaptic terminal. We investigated the role of mitochondria in compartmentalization of Ca 2+ We found that mitochondria form a dense cluster that acts as a diffusion barrier between the outer segment and cell body. The cluster is surprisingly only partially surrounded by the endoplasmic reticulum, a key mediator of mitochondrial Ca 2+ uptake. Blocking the uptake of Ca 2+ by mitochondria causes redistribution of Ca 2+ throughout the cell. Our results show that mitochondrial Ca 2+ uptake in photoreceptors is complex and plays an essential role in normal function. Copyright © 2017 the authors 0270-6474/17/372061-12$15.00/0.

  11. Ca²+/calmodulin-dependent protein kinase II (CaMKII activity and sinoatrial nodal pacemaker cell energetics.

    Directory of Open Access Journals (Sweden)

    Yael Yaniv

    Full Text Available : Ca(2+-activated basal adenylate cyclase (AC in rabbit sinoatrial node cells (SANC guarantees, via basal cAMP/PKA-calmodulin/CaMKII-dependent protein phosphorylation, the occurrence of rhythmic, sarcoplasmic-reticulum generated, sub-membrane Ca(2+ releases that prompt rhythmic, spontaneous action potentials (APs. This high-throughput signaling consumes ATP.We have previously demonstrated that basal AC-cAMP/PKA signaling directly, and Ca(2+ indirectly, regulate mitochondrial ATP production. While, clearly, Ca(2+-calmodulin-CaMKII activity regulates ATP consumption, whether it has a role in the control of ATP production is unknown.We superfused single, isolated rabbit SANC at 37°C with physiological saline containing CaMKII inhibitors, (KN-93 or autocamtide-2 Related Inhibitory Peptide (AIP, or a calmodulin inhibitor (W-7 and measured cytosolic Ca(2+, flavoprotein fluorescence and spontaneous AP firing rate. We measured cAMP, ATP and O2 consumption in cell suspensions. Graded reductions in basal CaMKII activity by KN-93 (0.5-3 µmol/L or AIP (2-10 µmol/L markedly slow the kinetics of intracellular Ca(2+ cycling, decrease the spontaneous AP firing rate, decrease cAMP, and reduce O2 consumption and flavoprotein fluorescence. In this context of graded reductions in ATP demand, however, ATP also becomes depleted, indicating reduced ATP production.CaMKII signaling, a crucial element of normal automaticity in rabbit SANC, is also involved in SANC bioenergetics.

  12. L-type Ca2+ channel blockers promote Ca2+ accumulation when dopamine receptors are activated in striatal neurons.

    Science.gov (United States)

    Eaton, Molly E; Macías, Wendy; Youngs, Rachael M; Rajadhyaksha, Anjali; Dudman, Joshua T; Konradi, Christine

    2004-11-24

    Dopamine (DA) receptor-mediated signal transduction and gene expression play a central role in many brain disorders from schizophrenia to Parkinson's disease to addiction. While trying to evaluate the role of L-type Ca2+ channels in dopamine D1 receptor-mediated phosphorylation of the transcription factor cyclic AMP response element-binding protein (CREB), we found that activation of dopamine D1 receptors alters the properties of L-type Ca2+ channel inhibitors and turns them into facilitators of Ca2+ influx. In D1 receptor-stimulated neurons, L-type Ca2+ channel blockers promote cytosolic Ca2+ accumulation. This leads to the activation of a molecular signal transduction pathway and CREB phosphorylation. In the absence of dopamine receptor stimulation, L-type Ca2+ channel blockers inhibit CREB phosphorylation. The effect of dopamine on L-type Ca2+ channel blockers is dependent on protein kinase A (PKA), suggesting that protein phosphorylation plays a role in this phenomenon. Because of the adverse effect of activated dopamine receptors on L-type Ca2+ channel blocker action, the role of L-type Ca2+ channels in the dopamine D1 receptor signal transduction pathway cannot be assessed with pharmacological tools. However, with antisense technology, we demonstrate that L-type Ca2+ channels contribute to D1 receptor-mediated CREB phosphorylation. We conclude that the D1 receptor signal transduction pathway depends on L-type Ca2+ channels to mediate CREB phosphorylation.

  13. Synthesis of Al₂Ca Dispersoids by Powder Metallurgy Using a Mg-Al Alloy and CaO Particles.

    Science.gov (United States)

    Fujita, Junji; Umeda, Junko; Kondoh, Katsuyoshi

    2017-06-28

    The elemental mixture of Mg-6 wt %Al-1 wt %Zn-0.3 wt %Mn (AZ61B) alloy powder and CaO particles was consolidated by an equal-channel angular bulk mechanical alloying (ECABMA) process to form a composite precursor. Subsequently, the precursor was subjected to a heat treatment to synthesize fine Al₂Ca particles via a solid-state reaction between the Mg-Al matrix and CaO additives. Scanning electron microscopy-energy-dispersive spectroscopy (SEM-EDS) and electron probe micro-analysis on the precursor indicated that 4.7-at % Al atoms formed a supersaturated solid solution in the α-Mg matrix. Transmission electron microscopy-EDS and X-ray diffraction analyses on the AZ61B composite precursor with 10-vol % CaO particles obtained by heat treatment confirmed that CaO additives were thermally decomposed in the Mg-Al alloy, and the solid-soluted Ca atoms diffused along the α-Mg grain boundaries. Al atoms also diffused to the grain boundaries because of attraction to the Ca atoms resulting from a strong reactivity between Al and Ca. As a result, needle-like (Mg,Al)₂Ca intermetallics were formed as intermediate precipitates in the initial reaction stage during the heat treatment. Finally, the precipitates were transformed into spherical Al₂Ca particles by the substitution of Al atoms for Mg atoms in (Mg,Al)₂Ca after a long heat treatment.

  14. PGC-1{alpha} accelerates cytosolic Ca{sup 2+} clearance without disturbing Ca{sup 2+} homeostasis in cardiac myocytes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Min, E-mail: chenminyx@gmail.com [Institute of Molecular Medicine, State Key Laboratory of Biomembrane and Membrane Biotechnology, Peking University, Beijing 100871 (China); Yunnan Centers for Diseases Prevention and Control, Kunming 650022 (China); Wang, Yanru [Institute of Molecular Medicine, State Key Laboratory of Biomembrane and Membrane Biotechnology, Peking University, Beijing 100871 (China); Qu, Aijuan [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2010-06-11

    Energy metabolism and Ca{sup 2+} handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1{alpha}) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1{alpha} in cardiac Ca{sup 2+} signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1{alpha} via adenoviral transduction. Our data shows that overexpressing PGC-1{alpha} improved myocyte contractility without increasing the amplitude of Ca{sup 2+} transients, suggesting that myofilament sensitivity to Ca{sup 2+} increased. Interestingly, the decay kinetics of global Ca{sup 2+} transients and Ca{sup 2+} waves accelerated in PGC-1{alpha}-expressing cells, but the decay rate of caffeine-elicited Ca{sup 2+} transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca{sup 2+}-ATPase (SERCA2a), but not Na{sup +}/Ca{sup 2+} exchange (NCX) contribute to PGC-1{alpha}-induced cytosolic Ca{sup 2+} clearance. Furthermore, PGC-1{alpha} induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1{alpha} did not disturb cardiac Ca{sup 2+} homeostasis, because SR Ca{sup 2+} load and the propensity for Ca{sup 2+} waves remained unchanged. These data suggest that PGC-1{alpha} can ameliorate cardiac Ca{sup 2+} cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1{alpha}-calcium handing pathway sheds new light on the role of PGC-1{alpha} in the therapy of cardiac diseases.

  15. Usefulness of CA 130 kit based on IRMA

    International Nuclear Information System (INIS)

    Fujii, Takashi; Kimura, Yoshiko; Ata, Mariko; Miyagawa, Naoko; Iio, Atsushi; Hamamoto, Ken

    1988-01-01

    Immunoradiometric assay for CA 130 was fundamentally and clinically evaluated using a commercially available D-7111 kit. Incubation time was 4 hr with the present CA 133 kit as compared with 16 - 24 hr with conventional CA 125 kit. Laboratory performance of CA 130 kit was satisfactory for standard curve, reproducibility, and recovery test. There was well correlation between the present CA 130 kit and CA 125 kit (r = 0.931). The concentration of CA 130 in the serum was significantly higher in healthy women than men (17.3 +- 10.5 U/ml vs 9.6 +- 5.1 U/ml). Serum CA 130 levels tended to decrease with aging, regardless of sex. These levels were changeable with menstrual cycle ; i.e., these were significantly higher during menstrual phase (24.2 +- 9.0 U/ml) and significantly lower during ovulatory phase (10.9 +- 2.4 U/ml) and during menopause (12.1 +- 3.4 U/ml). Cut off serum CA 130 levels were defined as 20 U/ml for men and 38 U/ml for women. Positive rate for CA 130 was the highest in cases of ovarian cancer (80 %), followed by endometrial cancer (50 %), pancreatic cancer (47 %), benign ovarian tumor (44 %), and lung cancer (39 %). (Namekawa, K.)

  16. The relationship between ovarian volume and serum CA-125 levels.

    Science.gov (United States)

    Gulec, U K; Paydas, S; Guzel, A B; Vardar, M A; Urunsak, I F; Cetin, M T

    2014-01-01

    The aim of this study was to investigate the relationship between ovarian volume and serum CA-125 levels. Serum CA-125 levels and ovarian volume were compared among the cases with benign ovarian neoplasms, primary epithelial ovarian cancer (EOC), controlled ovarian hyperstimulation, and ovarian hyperstimulation syndrome (OHSS). Also, the correlation between CA-125 levels and ovarian volume were evaluated in the presence of peritoneal fluid and/or peritoneal carcinomatosis. Although ovarian volume was not different among the groups, CA-125 levels were higher in the cases with EOC than with benign ovarian tumors (p = 0.001). Baseline CA-125 levels were not found to have increased while ovarian volume went up with controlled hyperstimulation in the infertile group (p = 0.555). However, uncontrolled hyperstimulation of the ovaries and the presence of peritoneal fluid caused an increase in the levels of CA-125 (p = 0.001). There was no correlation between ovarian volume and CA-125 levels in the cases with malignant ovarian tumors (r = 0.083). The results of this study have confirmed that CA-125 is a peritoneal marker and increased ovarian volume with benign ovarian neoplasms or controlled hyperstimulation does not increase CA-125 levels in the same way. The presence of peritoneal carcinomatosis and/or peritoneal fluid seems to be an important factor for high CA-125 levels in patients with epithelial ovarian cancer (EOC).

  17. FAST INVERSION OF SOLAR Ca II SPECTRA

    International Nuclear Information System (INIS)

    Beck, C.; Choudhary, D. P.; Rezaei, R.; Louis, R. E.

    2015-01-01

    We present a fast (<<1 s per profile) inversion code for solar Ca II lines. The code uses an archive of spectra that are synthesized prior to the inversion under the assumption of local thermodynamic equilibrium (LTE). We show that it can be successfully applied to spectrograph data or more sparsely sampled spectra from two-dimensional spectrometers. From a comparison to a non-LTE inversion of the same set of spectra, we derive a first-order non-LTE correction to the temperature stratifications derived in the LTE approach. The correction factor is close to unity up to log τ ∼ –3 and increases to values of 2.5 and 4 at log τ = –6 in the quiet Sun and the umbra, respectively

  18. Radiolise de Ca14Co3

    OpenAIRE

    Maria Guadalupe Albarran Sanchez

    1986-01-01

    Resumo: A ação da radiação sobre carbonatos sólidos produz várias espécies. A dissolução do sólido resulta na formação de alguns compostos orgânicos que podem ser observados por diferentes métodos químicos. Dentro destes métodos, o da cromatografia líquida de partição/exclusão de íons tem sido utilizada para análise dos ácidos carboxílicos produzidos. Nosso estudo consistiu em reexaminar este método de análise, estendendo-o para possíveis compostos não ionizáveis obtidos na radiólise de CaCO3...

  19. Hydroxylated xestospongins block inositol-1,4,5-trisphosphate-induced Ca2+ release and sensitize Ca2+-induced Ca2+ release mediated by ryanodine receptors.

    Science.gov (United States)

    Ta, Tram Anh; Feng, Wei; Molinski, Tadeusz F; Pessah, Isaac N

    2006-02-01

    Inositol-1,4,5-trisphosphate receptors (IP(3)Rs) and ryanodine receptors (RyRs) often coexist within the endoplasmic/sarcoplasmic reticulum (ER/SR) membrane and coordinate precise spatial and temporal coding of Ca(2+) signals in most animal cells. Xestospongin C (XeC) was shown to selectively block IP(3)-induced Ca(2+) release and IP(3)R-mediated signaling (Gafni et al., 1997). We have further studied the specificity of xestospongin structures possessing ring hydroxyl (-OH) substituents toward IP(3)R, RyR, and ER/SR Ca(2+)-ATPase (SERCA) activities. XeC potently inhibits IP(3)R, weakly inhibits RyR1, and lacks activity toward SERCA1 and SERCA2. XeD (9-OH XeC), 7-OH-XeA, and araguspongin C isolated from the marine sponge Xestospongia species also inhibit IP(3)-mediated Ca(2+) release and lack activity toward SERCA. However, these hydroxylated derivatives possess a unique activity in that they enhance Ca(2+)-induced Ca(2+) release from SR vesicles by a mechanism involving the sensitization of RyR1 channels within the same concentration range needed to block IP(3)-induced Ca(2+) release. These results show that xestospongins and related structures lack direct SERCA inhibitory activity, as suggested by some previous studies. A new finding is that XeD and related structures possessing a hydroxylated oxaquinolizidine ring are IP(3)R blockers that also enhance Ca(2+)-induced Ca(2+) release mediated by RyRs. In intact cells, the actions of XeD are blocked by ryanodine pretreatment and do not interfere with thapsigargin-mediated Ca(2+) mobilization stemming from SERCA block. Hydroxylated bis-oxaquinolizadine derivatives isolated from Xestospongia species are novel bifunctional reagents that may be useful in ascertaining how IP(3)Rs and RyRs contribute to cell signaling.

  20. The many phases of CaC{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Konar, Sumit; Nylén, Johanna; Svensson, Gunnar; Bernin, Diana; Edén, Mattias [Department of Materials and Environmental Chemistry, Stockholm University, SE-10691 Stockholm (Sweden); Ruschewitz, Uwe [Department of Chemistry, University of Cologne, Greinstrasse 6, 50939 Cologne (Germany); Häussermann, Ulrich, E-mail: Ulrich.Haussermann@mmk.su.se [Department of Materials and Environmental Chemistry, Stockholm University, SE-10691 Stockholm (Sweden)

    2016-07-15

    Polymorphic CaC{sub 2} was prepared by reacting mixtures of CaH{sub 2} and graphite with molar ratios between 1:1.8 and 1:2.2 at temperatures between 700 and 1400 °C under dynamic vacuum. These conditions provided a well controlled, homogeneous, chemical environment and afforded products with high purity. The products, which were characterized by powder X-ray diffraction, solid state NMR and Raman spectroscopy, represented mixtures of the three known polymorphs, tetragonal CaC{sub 2}-I and monoclinic CaC{sub 2}-II and -III. Their proportion is dependent on the nominal C/CaH{sub 2} ratio of the reaction mixture and temperature. Reactions with excess carbon produced a mixture virtually free from CaC{sub 2}-I, whereas high temperatures (above 1100 °C) and C-deficiency favored the formation of CaC{sub 2}-I. From first principles calculations it is shown that CaC{sub 2}-I is dynamically unstable within the harmonic approximation. This indicates that existing CaC{sub 2}-I is structurally/dynamically disordered and may possibly even occur as slightly carbon-deficient phase CaC{sub 2-δ}. It is proposed that monoclinic II is the ground state of CaC{sub 2} and polymorph III is stable at temperatures above 200 °C. Tetragonal I represents a metastable, heterogeneous, phase of CaC{sub 2}. It is argued that a complete understanding of the occurrence of three room temperature modifications of CaC{sub 2} will require a detailed characterization of compositional and structural heterogeneities within the high temperature form CaC{sub 2}-IV, which is stable above 450 °C. The effect of high pressure on the stability of the monoclinic forms of CaC{sub 2} was studied in a diamond anvil cell using Raman spectroscopy. CaC{sub 2}-II and -III transform into tetragonal CaC{sub 2}-I at about 4 and 1GPa, respectively. - Graphical abstract: The famous tetragonal form of CaC{sub 2}, CaC{sub 2}-I, is dynamically unstable. Why does it exist? Display Omitted - Highlights: • Critical review

  1. Enhanced Ca(2+)-activated Na(+)-Ca(2+) exchange activity in canine pacing-induced heart failure.

    Science.gov (United States)

    Hobai, I A; O'Rourke, B

    2000-10-13

    Defective excitation-contraction coupling in heart failure is generally associated with both a reduction in sarcoplasmic reticulum (SR) Ca(2+) uptake and a greater dependence on transsarcolemmal Na(+)-Ca(2+) exchange (NCX) for Ca(2+) removal. Although a relative increase in NCX is expected when SR function is impaired, few and contradictory studies have addressed whether there is an absolute increase in NCX activity. The present study examines in detail NCX density and function in left ventricular midmyocardial myocytes isolated from normal or tachycardic pacing-induced failing canine hearts. No change of NCX current density was evident in myocytes from failing hearts when intracellular Ca(2+) ([Ca(2+)](i)) was buffered to 200 nmol/L. However, when [Ca(2+)](i) was minimally buffered with 50 micromol/L indo-1, Ca(2+) extrusion via NCX during caffeine application was doubled in failing versus normal cells. In other voltage-clamp experiments in which SR uptake was blocked with thapsigargin, both reverse-mode and forward-mode NCX currents and Ca(2+) transport were increased >2-fold in failing cells. These results suggest that, in addition to a relative increase in NCX function as a consequence of defective SR Ca(2+) uptake, there is an absolute increase in NCX function that depends on [Ca(2+)](i) in the failing heart.

  2. Selenoprotein W redox-regulated Ca2+ channels correlate with selenium deficiency-induced muscles Ca2+ leak.

    Science.gov (United States)

    Yao, Haidong; Fan, Ruifeng; Zhao, Xia; Zhao, Wenchao; Liu, Wei; Yang, Jie; Sattar, Hamid; Zhao, Jinxin; Zhang, Ziwei; Xu, Shiwen

    2016-09-06

    Selenium (Se) deficiency induces Ca2+ leak and calcification in mammal skeletal muscles; however, the exact mechanism is still unclear. In the present study, both Se-deficient chicken muscle models and selenoprotein W (SelW) gene knockdown myoblast and embryo models were used to study the mechanism. The results showed that Se deficiency-induced typical muscular injuries accompanied with Ca2+ leak and oxidative stress (P CACNA1S, ORAI1, STIM1, TRPC1, and TRPC3 (P CACNA1S, ORA1, TRPC1, and TRPC3; and caused abnormal activities of Ca2+ channels in response to inhibitors in myoblasts and chicken embryos. Thus, both Se deficiency and SelW knockdown induced Ca2+ leak, oxidative stress, and Ca2+ channel reduction. In addition, Ca2+ levels and the expression of the Ca2+ channels, RyR1, SERCA, CACNA1S, TRPC1, and TRPC3 were recovered to normal levels by N-acetyl-L-cysteine (NAC) treatment compared with SelW knockdown cells. Thus, with regard to the decreased Ca2+ channels, SelW knockdown closely correlated Se deficiency with Ca2+ leak in muscles. The redox regulation role of SelW is crucial in Se deficiency-induced Ca2+ leak in muscles.

  3. Serum tetranectin and CA125 in endometrial adenocarcinoma

    DEFF Research Database (Denmark)

    Lundstrøm, M S; Høgdall, C K; Nielsen, Anette Lynge

    2000-01-01

    BACKGROUND: CA125 and tetranectin (TN) are prognostic markers in ovarian cancer. This study examines the values of these markers in endometrial cancer. MATERIALS AND METHODS: TN and CA125 were determined preoperatively in 99 patients with primary endometrioid adenocarcinoma and evaluated...... in relation to tumor grade, stage and cancer survival. RESULTS: The CA125 levels correlated significantly with tumor stage. Dichotomized according to a cut-off level of 35 U/ml, CA125 significantly correlated with cancer death. Multivariate regression analysis of cancer survival time showed that CA125 > 35 U....../ml was not an independent factor when stage was introduced. TN levels were within the normal range in all patients and did not show any association with tumor grade, stage or survival. CONCLUSIONS: The study confirmed the role of CA125 as a prognostic factor in endometrial cancer and may be of aid in pointing out patients...

  4. Residual sarcoplasmic reticulum Ca2+ concentration after Ca2+ release in skeletal myofibers from young adult and old mice.

    Science.gov (United States)

    Wang, Zhong-Min; Tang, Shen; Messi, María Laura; Yang, Jenny J; Delbono, Osvaldo

    2012-04-01

    Contrasting information suggests either almost complete depletion of sarcoplasmic reticulum (SR) Ca(2+) or significant residual Ca(2+) concentration after prolonged depolarization of the skeletal muscle fiber. The primary obstacle to resolving this controversy is the lack of genetically encoded Ca(2+) indicators targeted to the SR that exhibit low-Ca(2+) affinity, a fast biosensor: Ca(2+) off-rate reaction, and can be expressed in myofibers from adult and older adult mammalian species. This work used the recently designed low-affinity Ca(2+) sensor (Kd = 1.66 mM in the myofiber) CatchER (calcium sensor for detecting high concentrations in the ER) targeted to the SR, to investigate whether prolonged skeletal muscle fiber depolarization significantly alters residual SR Ca(2+) with aging. We found CatchER a proper tool to investigate SR Ca(2+) depletion in young adult and older adult mice, consistently tracking SR luminal Ca(2+) release in response to brief and repetitive stimulation. We evoked SR Ca(2+) release in whole-cell voltage-clamped flexor digitorum brevis muscle fibers from young and old FVB mice and tested the maximal SR Ca(2+) release by directly activating the ryanodine receptor (RyR1) with 4-chloro-m-cresol in the same myofibers. Here, we report for the first time that the Ca(2+) remaining in the SR after prolonged depolarization (2 s) in myofibers from aging (~220 μM) was larger than young (~132 μM) mice. These experiments indicate that SR Ca(2+) is far from fully depleted under physiological conditions throughout life, and support the concept of excitation-contraction uncoupling in functional senescent myofibers.

  5. Improved custom statistics visualization for CA Performance Center data

    CERN Document Server

    Talevi, Iacopo

    2017-01-01

    The main goal of my project is to understand and experiment the possibilities that CA Performance Center (CA PC) offers for creating custom applications to display stored information through interesting visual means, such as maps. In particular, I have re-written some of the network statistics web pages in order to fetch data from new statistics modules in CA PC, which has its own API, and stop using the RRD data.

  6. Circularly permuted green fluorescent proteins engineered to sense Ca2+.

    Science.gov (United States)

    Nagai, T; Sawano, A; Park, E S; Miyawaki, A

    2001-03-13

    To visualize Ca(2+)-dependent protein-protein interactions in living cells by fluorescence readouts, we used a circularly permuted green fluorescent protein (cpGFP), in which the amino and carboxyl portions had been interchanged and reconnected by a short spacer between the original termini. The cpGFP was fused to calmodulin and its target peptide, M13. The chimeric protein, which we have named "pericam," was fluorescent and its spectral properties changed reversibly with the amount of Ca(2+), probably because of the interaction between calmodulin and M13 leading to an alteration of the environment surrounding the chromophore. Three types of pericam were obtained by mutating several amino acids adjacent to the chromophore. Of these, "flash-pericam" became brighter with Ca(2+), whereas "inverse-pericam" dimmed. On the other hand, "ratiometric-pericam" had an excitation wavelength changing in a Ca(2+)-dependent manner. All of the pericams expressed in HeLa cells were able to monitor free Ca(2+) dynamics, such as Ca(2+) oscillations in the cytosol and the nucleus. Ca(2+) imaging using high-speed confocal line-scanning microscopy and a flash-pericam allowed to detect the free propagation of Ca(2+) ions across the nuclear envelope. Then, free Ca(2+) concentrations in the nucleus and mitochondria were simultaneously measured by using ratiometric-pericams having appropriate localization signals, revealing that extra-mitochondrial Ca(2+) transients caused rapid changes in the concentration of mitochondrial Ca(2+). Finally, a "split-pericam" was made by deleting the linker in the flash-pericam. The Ca(2+)-dependent interaction between calmodulin and M13 in HeLa cells was monitored by the association of the two halves of GFP, neither of which was fluorescent by itself.

  7. SNL/CA Environmental Management System Program Manual.

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Barbara L.

    2007-04-01

    The Sandia National Laboratories, California (SNL/CA) Environmental Management System (EMS) Program Manual documents the elements of the site EMS Program. The SNL/CA EMS Program conforms to the International Standard on Environmental Management Systems, ISO 14001:2004. Elements of the ISO standard overlap with those of Department of Energy (DOE) Order 450.1, thus SNL/CA's EMS program also meets the DOE requirements.

  8. Combined Evaluation of AFP, CA15-3, CA125, CA19-9, and CEA Tumor Markers in Patients with Hepatitis B and C.

    Science.gov (United States)

    Assmar, Mehdi; Yeganeh, Sara; Mansourghanaei, Fariborz; Amirmozafari, Nour

    2016-12-01

    This study aimed to determine the role of tumor markers AFP, CA15-3, CA125, CA19-9 and CEA in patients with hepatitis B and C. This descriptive cross-sectional study was performed from Oct 2012 to Oct 2014. Serum samples of 129 patients with hepatitis B and C referred to Guilan Liver and Digestive Disease Research Center in Rasht, Iran were collected and checked for the existence of the listed tumor markers by ELISA. No increase in serum levels of tumor marker CA19-9, CEA and CA15-3 were seen in patients with hepatitis ( P >0.05). In patients with hepatitis B, increase in CA125 were observed ( P =0.03). In hepatitis C patients, there was an increase in AFP levels ( P =0.03). The levels of AFP and CA125 markers were high in hepatitis C and hepatitis B, respectively. However, the increased levels were not seen is malignancy. Due to the small sample size, further study is necessary to find the reasons of the increase.

  9. Influence of Ca substitution by Mg on the Ca3Co4O9 performances

    Directory of Open Access Journals (Sweden)

    Constantinescu, G.

    2014-02-01

    Full Text Available Ca3-xMgxCo4O9 polycrystalline thermoelectric ceramics with small amounts of Mg have been synthesized by the classical solid state method. Microstructural characterizations have shown that all the Mg has been incorporated into the Ca3Co4O9 structure and no Mg-based secondary phases have been identified. Apparent density measurements have shown that samples do not modify their density until 0.05 Mg content, decreasing for higher contents. Electrical resistivity decreases and Seebeck coefficient slightly raises when Mg content increases until 0.05 Mg addition. The improvement in both parameters leads to higher power factor values than the usually obtained in samples prepared by the conventional solid state routes and close to those obtained in textured materials.Se han preparado cerámicas termoeléctricas policristalinas de Ca3-xMgxCo4O9, con pequeñas cantidades de Mg, utilizando el método clásico de estado sólido. La caracterización microestructural ha mostrado que el Mg se ha incorporado en la estructura del Ca3Co4O9 y que no se han formado fases secundarias con el Mg. Las medidas de densidad aparente han mostrado que las muestras prácticamente poseen la misma densidad hasta un contenido de 0.05 Mg, disminuyendo para contenidos mayores. La resistividad eléctrica disminuye y el coeficiente Seebeck aumenta cuando el contenido de Mg se incrementa hasta valores de 0.05. La mejora de ambos parámetros conduce a valores del factor de potencia mayores que los obtenidos en muestras preparadas por la vía convencional de estado sólido, alcanzando valores próximos a los que se encuentran en materiales texturados.

  10. A new tumor marker: CA125 for ovarian carcinomas

    International Nuclear Information System (INIS)

    Sakahara, H.; Endo, K.; Nakajima, K.

    1985-01-01

    To evaluate CA125 as a tumor marker for ovarian carcinomas, CA125 concentrations were measured by the simultaneous immunoradiometric assay. The binding of I-125 labeled monoclonal antibody to the bead-bound antigen was greatly influenced by many factors, such as the incubation time, pH, IgG concentrations of samples, the sequence of addition of the tracer and samples and so on. By applying the forward two-step assay, diminished binding was observed than in the simultaneous assay, probably due to the relatively low affinity of the antibody. This simultaneous immunoradiometric assay resulted in the ''prozone'' or ''hook'' effect at high CA125 samples and proper dilution was necessary to determine the accurate CA125 values. All 72 normal control subjects had low concentrations of under 35 U/ml. Elevated serum CA125 was observed in 43% (9/21) cases with malignant ovarian tumors, depending on the stage and the histopathological findings. All 4 serous cystadenocarcinomas and 2 of 3 endometrioid carcinomas were positive and the measurement of serum CA125 was useful in the sequential monitoring of these cases. In contrast, 51 benign gynecological diseases, none had elevated serum CA125 except one with follicular cyst. Among 75 cases with non-gynecological benign and malignant diseases, only 1 of 12 gastric carcinomas and 2 of 13 pancreatic carcinomas had elevated CA125 levels. In summary, CA125 is a promising and relatively specific marker for ovarian carcinomas

  11. TRPV5-mediated Ca2+ Reabsorption and Hypercalciuria

    Science.gov (United States)

    Renkema, Kirsten Y.; Hoenderop, Joost G. J.; Bindels, René J. M.

    2007-04-01

    The concerted action of the intestine, kidney and bone results in the maintenance of a normal Ca2+ balance, a mechanism that is tightly controlled by the calciotropic hormones vitamin D, parathyroid hormone and calcitonin. Disturbances in the Ca2+ balance have been linked to diverse pathophysiological disorders like urolithiasis, hypertension, electroencephalogram abnormalities and rickets. Importantly, the final amount of Ca2+ that is released from the body is determined in the distal part of the nephron, where active Ca2+ reabsorption occurs. Here, Transient Receptor Potential Vanilloid member 5 (TRPV5), a highly Ca2+-selective channel, has been recognized as the gatekeeper of active Ca2+ reabsorption. The in vivo relevance of TRPV5 has been further investigated by the characterization of TRPV5 knockout (TRPV5-/-) mice, which exhibit severe disturbances in renal Ca2+ handling, such as profound hypercalciuria, intestinal Ca2+ hyperabsorption and reduced bone thickness. Hypercalciuria increases the risk of kidney stone formation in these mice. This review highlights our current knowledge about TRPV5-mediated Ca2+ reabsorption and emphasizes the physiological relevance and the clinical implications related to the TRPV5-/- mice model.

  12. Hydriding and dehydriding properties of CaSi

    International Nuclear Information System (INIS)

    Aoki, Masakazu; Ohba, Nobuko; Noritake, Tatsuo; Towata, Shin-ichi

    2005-01-01

    The hydriding and dehydriding properties of CaSi were investigated both theoretically and experimentally. First-principles calculations suggested that CaSiH n is thermodynamically stable. Experimentally, the p -c isotherms clearly demonstrated plateau pressures in a temperature range of 473-573 K and the maximum hydrogen content was 1.9 weight % (wt.%) under a hydrogen pressure of 9 MPa at 473 K. The structure of CaSiH n is different from those of ZrNi hydrides, although CaSi has the CrB-type structure as well as ZrNi

  13. β decay of neutron-rich 53-56Ca

    International Nuclear Information System (INIS)

    Mantica, P. F.; Crawford, H. L.; Damaske, A.; Pinter, J. S.; Stoker, J. B.; Broda, R.; Fornal, B.; Hecht, A. A.; Hoteling, N.; Hoffman, C.; Tabor, S. L.; Walters, W. B.; Horoi, M.; Janssens, R. V. F.; Zhu, S.; Pereira, J.; Sumikama, T.; Wang, X.

    2008-01-01

    β-decay properties of neutron-rich Ca isotopes have been obtained. Half-life values were determined for the first time for 54 Ca (86±7 ms), 55 Ca (22±2 ms), and 56 Ca (11±2 ms). The half-life of 230±60 ms deduced for 53 Ca is significantly longer than reported previously, where the decay chain 53 K → 53 Ca → 53 Sc was considered. A delayed γ ray with an energy of 247 keV was identified following β decay of 54 Ca and is proposed to depopulate the 1 1 + level in 54 Sc. The β-decay properties compare favorably with the results of shell-model calculations completed in the full pf space with the GXPF1 interaction. The half-lives of the neutron-rich Ca isotopes are also compared with gross β-decay theory. The systematic trend of the neutron-rich Ca half-lives is consistent with the presence of a subshell gap at N=32

  14. Kinetic studies of calcium in human by 41Ca tracing

    International Nuclear Information System (INIS)

    Boaretto, E.; Paul, M.; Gelbart, Z.; Johnson, R.R.; Meirav, O.; Sossi, V.; Venczel, E.; Hollos, G.; Prior, J.

    1992-01-01

    41 Ca (T 1/2 = 1 x 10 5 years) is an ideal tracer for long-term studies of calcium kinetics in biological systems for several reasons: (a) it behaves as a stable nuclide for all practical purpose due to its very long radioactive half-life; (b) its natural abundance is extremely low; (c) 41 Ca isotopic concentrations can now be measured to very high sensitivity by accelerator mass spectrometry, requiring therefore injection doses with no collateral radiation effects. Such an experiment has been initiated in a human subject by intravenous injection of a 126 ng dose of 41 Ca on July 18, 1990. The 41 Ca concentration and the 41 Ca/Ca isotopic ratios in serum and urine have been measured at five times over a 270 days period, showing a decrease in agreement with known time constants of the different calcium pools. It is planned to follow up the steady-state 41 Ca level ( 41 Ca/Ca ∼9 x 10 -12 ) over time (e.g. menstrual cycle, age)

  15. Pathways for Energization of Ca in Mercury's Exosphere

    Science.gov (United States)

    Killen, Rosemary M.

    2015-01-01

    We investigate the possible pathways to produce the extreme energy observed in the calcium exosphere of Mercury. Any mechanism must explain the facts that Ca in Mercury's exosphere is extremely hot, that it is seen almost exclusively on the dawnside of the planet, and that its content varies seasonally, not sporadically. Simple diatomic molecules or their clusters are considered, focusing on calcium oxides while acknowledging that Ca sulfides may also be the precursor molecules. We first discuss impact vaporization to justify the assumption that CaO and Ca-oxide clusters are expected from impacts on Mercury. Then we discuss processes by which the atomic Ca is energized to a 70,000 K gas. The processes considered are (1) electron-impact dissociation of CaO molecules, (2) spontaneous dissociation of Ca-bearing molecules following impact vaporization, (3) shock-induced dissociative ionization, (4) photodissociation and (5) sputtering. We conclude that electron-impact dissociation cannot produce the required abundance of Ca, and sputtering cannot reproduce the observed spatial and temporal variation that is measured. Spontaneous dissociation is unlikely to result in the high energy that is seen. Of the two remaining processes, shock induced dissociative ionization produces the required energy and comes close to producing the required abundance, but rates are highly dependent on the incoming velocity distribution of the impactors. Photodissociation probably can produce the required abundance of Ca, but simulations show that photodissociation cannot reproduce the observed spatial distribution.

  16. Vibrational spectroscopic study of poldervaartite CaCa[SiO3(OH)(OH)

    Science.gov (United States)

    Frost, Ray L.; López, Andrés; Scholz, Ricardo; Lima, Rosa Malena Fernandes

    2015-02-01

    We have studied the mineral poldervaartite CaCa[SiO3(OH)(OH)] which forms a series with its manganese analogue olmiite CaMn[SiO3(OH)](OH) using a range of techniques including scanning electron microscopy, thermogravimetric analysis, Raman and infrared spectroscopy. Chemical analysis shows the mineral is reasonably pure and contains only calcium and manganese with low amounts of Al and F. Thermogravimetric analysis proves the mineral decomposes at 485 °C with a mass loss of 7.6% compared with the theoretical mass loss of 7.7%. A strong Raman band at 852 cm-1 is assigned to the SiO stretching vibration of the SiO3(OH) units. Two Raman bands at 914 and 953 cm-1 are attributed to the antisymmetric vibrations. Intense prominent peaks observed at 3487, 3502, 3509, 3521 and 3547 cm-1 are assigned to the OH stretching vibration of the SiO3(OH) units. The observation of multiple OH bands supports the concept of the non-equivalence of the OH units. Vibrational spectroscopy enables a detailed assessment of the molecular structure of poldervaartite.

  17. Nonspatial Sequence Coding in CA1 Neurons.

    Science.gov (United States)

    Allen, Timothy A; Salz, Daniel M; McKenzie, Sam; Fortin, Norbert J

    2016-02-03

    The hippocampus is critical to the memory for sequences of events, a defining feature of episodic memory. However, the fundamental neuronal mechanisms underlying this capacity remain elusive. While considerable research indicates hippocampal neurons can represent sequences of locations, direct evidence of coding for the memory of sequential relationships among nonspatial events remains lacking. To address this important issue, we recorded neural activity in CA1 as rats performed a hippocampus-dependent sequence-memory task. Briefly, the task involves the presentation of repeated sequences of odors at a single port and requires rats to identify each item as "in sequence" or "out of sequence". We report that, while the animals' location and behavior remained constant, hippocampal activity differed depending on the temporal context of items-in this case, whether they were presented in or out of sequence. Some neurons showed this effect across items or sequence positions (general sequence cells), while others exhibited selectivity for specific conjunctions of item and sequence position information (conjunctive sequence cells) or for specific probe types (probe-specific sequence cells). We also found that the temporal context of individual trials could be accurately decoded from the activity of neuronal ensembles, that sequence coding at the single-cell and ensemble level was linked to sequence memory performance, and that slow-gamma oscillations (20-40 Hz) were more strongly modulated by temporal context and performance than theta oscillations (4-12 Hz). These findings provide compelling evidence that sequence coding extends beyond the domain of spatial trajectories and is thus a fundamental function of the hippocampus. The ability to remember the order of life events depends on the hippocampus, but the underlying neural mechanisms remain poorly understood. Here we addressed this issue by recording neural activity in hippocampal region CA1 while rats performed a

  18. Determination of standard free energies of formation of Ca3P2 and Ca2Sn at high temperatures

    Science.gov (United States)

    Min, D. J.; Sano, N.

    1988-06-01

    The standard free energies of formation of calcium phosphide and calcium stannide were determined by a chemical equilibration technique, yielding the following results: 3Ca(1) + P2(g) = Ca3P2(s) Δ G° = -653,460(±7110) + 144.01(±4.98) T (J/mol)1000 °C to 1300 °C2Ca(1) + Sn(1) = Ca2Sn(s) Δ G° = -353,970(±1670) + 79.28(±1.26) T (J/mol)1000 °C to 1300 °C 1120 °C The experimental data to express the thermodynamics for removal of phosphorus and tin from molten iron by calcium based slags by other investigators were discussed in terms of the activity co-efficients of Ca3P2 and Ca2Sn in slag melts by using the present results described above.

  19. Tumour associated antigen CA-50, CA-242 immunoradiometric assay (IRMA) in genitourinary malignancy and gastrointestinal carcinoma early diagnosis

    International Nuclear Information System (INIS)

    Chen Zhizhou.

    1992-04-01

    Tumour markers CA-50 and CA-242 were measured by immunometric assay (IRMA) to investigate their usefulness in the diagnosis of cancer of the pancreas, biliary tract, liver, breast, lung, gastrointestinal and genitourinary systems. The cutoff points, derived from studies on normal subjects and those with proven benign disease, were 20 u/ml and 12 u/ml for CA-50 and CA-242 respectively. Both markers were found to be generally useful with significant differences between malignant and non malignant disease. The highest positive rates, were found in cancers of the pancreas and gall bladder. The overall rate of false positives was low. It is concluded that measurements of CA-50 and CA-242 are useful in the detection of malignancy, particularly of the pancreas and biliary tract. 2 figs, 2 tabs

  20. Elementary properties of CaV1.3 Ca2+ channels expressed in mouse cochlear inner hair cells

    Science.gov (United States)

    Zampini, Valeria; Johnson, Stuart L; Franz, Christoph; Lawrence, Neil D; Münkner, Stefan; Engel, Jutta; Knipper, Marlies; Magistretti, Jacopo; Masetto, Sergio; Marcotti, Walter

    2010-01-01

    Mammalian cochlear inner hair cells (IHCs) are specialized to process developmental signals during immature stages and sound stimuli in adult animals. These signals are conveyed onto auditory afferent nerve fibres. Neurotransmitter release at IHC ribbon synapses is controlled by L-type CaV1.3 Ca2+ channels, the biophysics of which are still unknown in native mammalian cells. We have investigated the localization and elementary properties of Ca2+ channels in immature mouse IHCs under near-physiological recording conditions. CaV1.3 Ca2+ channels at the cell pre-synaptic site co-localize with about half of the total number of ribbons present in immature IHCs. These channels activated at about −70 mV, showed a relatively short first latency and weak inactivation, which would allow IHCs to generate and accurately encode spontaneous Ca2+ action potential activity characteristic of these immature cells. The CaV1.3 Ca2+ channels showed a very low open probability (about 0.15 at −20 mV: near the peak of an action potential). Comparison of elementary and macroscopic Ca2+ currents indicated that very few Ca2+ channels are associated with each docked vesicle at IHC ribbon synapses. Finally, we found that the open probability of Ca2+ channels, but not their opening time, was voltage dependent. This finding provides a possible correlation between presynaptic Ca2+ channel properties and the characteristic frequency/amplitude of EPSCs in auditory afferent fibres. PMID:19917569

  1. RESEM-CA: Validation and testing

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Vineeta; Carroll, William L.; Bourassa, Norman

    2002-09-01

    This report documents the results of an extended comparison of RESEM-CA energy and economic performance predictions with the recognized benchmark tool DOE2.1E to determine the validity and effectiveness of this tool for retrofit design and analysis. The analysis was a two part comparison of patterns of (1) monthly and annual energy consumption of a simple base-case building and controlled variations in it to explore the predictions of load components of each program, and (2) a simplified life-cycle cost analysis of the predicted effects of selected Energy Conservation Measures (ECMs). The study tries to analyze and/or explain the differences that were observed. On the whole, this validation study indicates that RESEM is a promising tool for retrofit analysis. As a result of this study some factors (incident solar radiation, outside air film coefficient, IR radiation) have been identified where there is a possibility of algorithmic improvements. These would have to be made in a way that does not sacrifice the speed of the tool, necessary for extensive parametric search of optimum ECM measures.

  2. 48Ca HETEROGENEITY IN DIFFERENTIATED METEORITES

    International Nuclear Information System (INIS)

    Chen, Hsin-Wei; Lee, Typhoon; Lee, Der-Chuen; Shen, Jason Jiun-San; Chen, Jiang-Chang

    2011-01-01

    Isotopic heterogeneities of 48 Ca have been found in numerous bulk meteorites that are correlated with 50 Ti and 54 Cr anomalies among differentiated planetary bodies, and the results suggest that a rare subset of neutron-rich Type Ia supernova (nSN Ia) was responsible for contributing these neutron-rich iron-group isotopes into the solar system (SS). The heterogeneity of these isotopes found in differentiated meteorites indicates that the isotopic compositions of the bulk SS are not uniform, and there are significant amounts of nSNe Ia dust incompletely mixed with the rest of SS materials during planetary formation. Combined with the data of now-extinct short-lived nuclide 60 Fe, which can be produced more efficiently from an nSN Ia than a Type II supernova ejecta, the observed planetary-scale isotopic heterogeneity probably reflects a late input of stellar dust grains with neutron-rich nuclear statistical equilibrium nuclides into the early SS.

  3. Asymmetries of the solar Ca II lines

    International Nuclear Information System (INIS)

    Heasley, J.N.

    1975-01-01

    A theoretical study of the influence of propagating acoustic pulses in the solar chromosphere upon the line profiles of the Ca II resonance and infrared triplet lines has been made. The major objective has been to explain the observed asymmetries seen in the cores of the H and K lines and to predict the temporal behavior of the infrared lines caused by passing acoustic or shock pulses. The velocities in the pulses, calculated from weak shock theory, have been included consistently in the non-LTE calculations. The results of the calculations show that these lines are very sensitive to perturbations in the background atmosphere caused by the pulses. Only minor changes in the line shapes result from including the velocities consistently in the line source function calculations. The qualitative changes in the line profiles vary markedly with the strength of the shock pulses. The observed differences in the K line profiles seen on the quiet Sun can be explained in terms of a spectrum of pulses with different wavelengths and initial amplitudes in the photosphere. (Auth.)

  4. Flavonoid Myricetin Modulates GABAA Receptor Activity through Activation of Ca2+ Channels and CaMK-II Pathway

    Directory of Open Access Journals (Sweden)

    Xiao Hu Zhang

    2012-01-01

    Full Text Available The flavonoid myricetin is found in several sedative herbs, for example, the St. John's Wort, but its influence on sedation and its possible mechanism of action are unknown. Using patch-clamp technique on a brain slice preparation, the present study found that myricetin promoted GABAergic activity in the neurons of hypothalamic paraventricular nucleus (PVN by increasing the decay time and frequency of the inhibitory currents mediated by GABAA receptor. This effect of myricetin was not blocked by the GABAA receptor benzodiazepine- (BZ- binding site antagonist flumazenil, but by KN-62, a specific inhibitor of the Ca2+/calmodulin-stimulated protein kinase II (CaMK-II. Patch clamp and live Ca2+ imaging studies found that myricetin could increase Ca2+ current and intracellular Ca2+ concentration, respectively, via T- and L-type Ca2+ channels in rat PVN neurons and hypothalamic primary culture neurons. Immunofluorescence staining showed increased phosphorylation of CaMK-II after myricetin incubation in primary culture of rat hypothalamic neurons, and the myricetin-induced CaMK-II phosphorylation was further confirmed by Western blotting in PC-12 cells. The present results suggest that myricetin enhances GABAA receptor activity via calcium channel/CaMK-II dependent mechanism, which is distinctively different from that of most existing BZ-binding site agonists of GABAA receptor.

  5. Ab-initio calculations of the Ruddlesden-Popper phases CaMnO{sub 3}, CaO(CaMnO{sub 3}) and CaO(CaMnO{sub 3}){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, C [CFC, Physics Department, University of Coimbra, 3004-516 Coimbra (Portugal); Borges, R P [Centro de Fisicada Materia Condensada - Universidade de Lisboa, Campo Grande, Ed. C8, 1749-016, Lisbon (Portugal); Gasche, T [Centro de Fisicada Materia Condensada - Universidade de Lisboa, Campo Grande, Ed. C8, 1749-016, Lisboa (Portugal); Godinho, M [Centro de Fisicada Materia Condensada - Universidade de Lisboa, Campo Grande, Ed. C8, 1749-016, Lisbon (Portugal)

    2008-01-23

    The present work reports ab-initio density functional theory calculations for the Ruddlesden-Popper phase CaO(CaMnO{sub 3}){sub n} compounds. In order to study the evolution of the properties with the number of perovskite layers, a detailed analysis of the densities of states calculated for each compound and for several magnetic configurations was performed. The effect of distortions of the crystal structure on the magnetic ground state is also analysed and the exchange constants and transition temperatures are calculated for the three compounds using a mean field model. The calculated magnetic ground state structures and magnetic moments are in good agreement with experimental results and previous calculations.

  6. Clinical analysis of the value of combined detection of serum CA199 and CA50 levels in patients with pancreatic cancer

    International Nuclear Information System (INIS)

    Zhang Zhuo; Shi Jingbin; Zheng Yongsheng

    2001-01-01

    Objective: To investigate the clinical value of combined test of serum CA 199 and CA 50 levels in the diagnosis and prognosis of patients with pancreatic cancer. Methods: Serum levels of CA 199 and CA 50 in 40 cases of pancreatic cancer, 20 cases of chronic pancreatitis and 30 normal controls were detected by radioimmunoassay. Results: Serum CA 199 and CA 50 levels in pancreatic cancer patients were significantly higher than those in normal controls and chronic pancreatitis patients (P 199 and CA 50 were detected simultaneously, the sensitivity, specificity and accuracy of diagnosis of pancreatic cancer could be improved. Serum CA 199 and CA 50 levels in cancer patients with lymph node metastasis were much higher than those without lymph node metastasis (P 199 and CA 50 detected simultaneously could improve the sensitivity and accuracy in diagnosis of pancreatic cancer. The changes of serum CA 199 and CA 50 level were helpful to predict whether metastasis or recurrence had occurred

  7. Clinical evaluation of CEA, CA19-9, CA72-4 and CA125 in gastric cancer patients with neoadjuvant chemotherapy.

    Science.gov (United States)

    Sun, Zhipeng; Zhang, Nengwei

    2014-12-29

    In the clinical practice of neoadjuvant chemotherapy, response markers are very important. We aimed o investigate whether tumor markers CEA(carcino-embryonic antigen), CA19-9(carbohydrate antigen 19-9), CA72-4(carbohydrate antigen 72-4), and CA125(carbohydrate antigen 125) can be used to evaluate the response to neoadjuvant chemotherapy, and to evaluate the diagnosis and prognosis value of four tumor markers in the patients of gastric cancer. A retrospective review was performed of 184 gastric cancer patients who underwent a 5-Fu, leucovorin, and oxaliplatin (FOLFOX) neoadjuvant chemotherapy regimen, followed by surgical treatment. Blood samples for CEA, CA19-9, CA72-4, and CA125 levels were taken from patients upon admission to the hospital and after neoadjuvant chemotherapy. Statistical analysis was performed to identify the clinical value of these tumor markers in predicting the survival and the response to neoadjuvant chemotherapy. Median overall survival times of pretreatment CA19-9-positive and CA72-4-positive patients (14.0 +/-2.8 months and 14.8 +/-4.0 months, respectively) were significantly less than negative patients (32.5 +/-8.9 months and 34.0 +/-10.1 months, respectively) (P = 0.000 and P = 0.002, respectively). Pretreatment status of CA19-9 and CA72-4 were independent prognostic factors in gastric cancer patients (P = 0.029 and P = 0.008, respectively). Pretreatment CEA >50 ng/ml had a positive prediction value for clinical disease progression after neoadjuvant chemotherapy according to the ROC curve (AUC: 0.694, 95% CI: 0.517 to 0.871, P = 0.017). The decrease of tumor markers CEA, CA72-4, and CA125 was significant after neoadjuvant chemotherapy (P = 0.030, P = 0.010, and P = 0.009, respectively), especially in patients with disease control (including complete, partial clinical response, and stable disease) (P = 0.012, P = 0.020, and P = 0.025, respectively). A decrease in CA72-4 by more than 70% had

  8. The diagnostic value of serum tumor markers CEA, CA19-9, CA125, CA15-3, and TPS in metastatic breast cancer.

    Science.gov (United States)

    Wang, Weigang; Xu, Xiaoqin; Tian, Baoguo; Wang, Yan; Du, Lili; Sun, Ting; Shi, Yanchun; Zhao, Xianwen; Jing, Jiexian

    2017-07-01

    This study aims to understand the diagnostic value of serum tumor markers carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9), cancer antigen 125 (CA125), cancer antigen 15-3 (CA15-3), and tissue polypeptide-specific antigen (TPS) in metastatic breast cancer (MBC). A total of 164 metastatic breast cancer patients in Shanxi Cancer Hospital were recruited between February 2016 and July 2016. 200 breast cancer patients without metastasis in the same period were randomly selected as the control group. The general characteristics, immunohistochemical, and pathological results were investigated between the two groups, and tumor markers were determined. There were statistical differences in the concentration and the positive rates of CEA, CA19-9, CA125, CA15-3, and TPS between the MBC and control group (Ptumor marker at 56.7% and 97.0%, respectively. In addition, two tumor markers were used for the diagnosis of MBC and the CEA and TPS combination had the highest diagnostic sensitivity with 78.7%, while the CA15-3 and CA125 combination had the highest specificity of 91.5%. Analysis of tumor markers of 164 MBC found that there were statistical differences in the positive rates of CEA and CA15-3 between bone metastases and other metastases (χ 2 =6.00, P=0.014; χ 2 =7.32, P=0.007, respectively). The sensitivity and specificity values of the CEA and CA15-3 combination in the diagnosis of bone metastases were 77.1% and 45.8%, respectively. The positive rate of TPS in the lung metastases group was lower than in other metastases (χ 2 =8.06, P=0.005).There were significant differences in the positive rates of CA15-3 and TPS between liver metastases and other metastases (χ 2 =15.42, Ptumor markers have varying diagnostic value. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Preparation of 45Ca(HDEHP)n and (CaH1502)2 samples for liquid scintillation counting, compared to 45caCl2 results

    International Nuclear Information System (INIS)

    Rodriguez, L.; Arcos, J. M. los; Grau Malonda, A.

    1994-01-01

    A procedure for preparation of liquid scintillation counting organic samples of the Di-2-ethylhexyl phosphate calcium complex and the 2-ethylhexanoate calcium salt, labelled with 45Ca, is described. The chemical quench, the counting stability and spectral evolution of both compounds is studied in six scintillators,Toluene-alcohol, Dioxane-naphtalene, Hi safe II, Ultimate-Gold and Instagel, and compared to results obtained from a commercial solution of 4 5CaCl2. (Author) 7 refs

  10. Studies of highly ionized atoms using internal conversion: 197Au, 57Fe; electric monopole transitions in 40Ca, 42Ca, and 44Ca

    International Nuclear Information System (INIS)

    Ulrickson, M.A.

    1975-01-01

    By using heavy-ion reactions, highly ionized electronic states of atoms may be produced. The interaction between excited nuclear levels and the surrounding atomic electrons via internal conversion allows the nucleus to be used as a probe of the electronic structure of the highly ionized atoms. Studies of such atoms were undertaken for strongly internally converted nuclear levels in 197 Au and 57 Fe. The nuclear levels were Coulomb excited by using 16 O and 32 S beams. Simultaneous measurement of the lifetime of the 77-keV state of 197 Au in both neutral gold atoms and gold atoms with mean charge +10 resulted in a measured change in the internal conversion coefficient of Δalpha/alpha equals - 1.7 +- 3.0)10 -3 . This result is consistent with calculations using a Hartree-Fock--Slater program. Measurements of the electric monopole strengths for 0 + → 0 + transitions were undertaken to determine the amount of core-deformation in calcium nuclei. The E0 strengths for the decays of the 0 + states at 5.21 MeV in 40 C, 1.84 MeV in 42 Ca, and 1.88 MeV in 44 Ca were observed. The branching ratios for the subsequent E0 pair decays were measured by observing the coincident annihilation radiation from the e + member of the pair in coincidence with protons feeding the state in the cases of 42 Ca and 44 Ca, and by observing the actual coincident e + --e - pair together with protons feeding the state in the case of 40 Ca. The resulting E0 strengths (rho less than or equal to 0.06, rho = 0.34 +- 0.03, rho = 0.30 +- 0.10 for 40 Ca, 42 Ca, and 44 Ca respectively) agree with theoretical descriptions

  11. {sup 41}Ca measurements at the Zurich AMS facility

    Energy Technology Data Exchange (ETDEWEB)

    Schnabel, C.; Gartenmann, P.; Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Gloris, M.; Leya, I.; Michel, R. [Hannover Univ. (Germany); Herpers, U. [Koeln Univ. (Germany)

    1997-09-01

    Proton-induced production cross sections for {sup 41}Ca from Fe and Ni determined using 6 MV tandem accelerator are presented. The calibration of two secondary standard materials to a standard material of {sup 41}Ca concentration determined by PTB (Braunschweig, Germany) has been carried out. (author) 2 figs., 3 refs.

  12. Isolation and characterization of higher metallofullerenes Ca@ C 92 ...

    Indian Academy of Sciences (India)

    ... technique without recycling equipment. It is notable that higher metallofullerenes containing alkaline earth metal ions could be isolated although their relative yields are extremely low. Ca@C92 and Ca@C94 are also confirmed by LD-TOF mass spectrometry and characterrized by UV-Vis-NIR absorption measurements.

  13. Characterization of Binding Epitopes of CA125 Monoclonal Antibodies

    DEFF Research Database (Denmark)

    Marcos-Silva, Lara; Narimatsu, Yoshiki; Halim, Adnan

    2014-01-01

    The most used cancer serum biomarker is the CA125 immunoassay for ovarian cancer that detects the mucin glycoprotein MUC16. Several monoclonal antibodies (mAbs) including OC125 and M11 are used in CA125 assays. However, despite considerable efforts, our knowledge of the molecular characteristics ...

  14. Isolation and characterization of higher metallofullerenes Ca@C92 ...

    Indian Academy of Sciences (India)

    Administrator

    allofullerenes containing alkaline earth metal ions could be isolated although their relative yields are extremely low. Ca@C92 and Ca@C94 are also ... est cage size for lanthanide and alkaline earth higher metallofullerenes isolated and ... suming stage is to remove abundant hollow small cage fullerenes and enrich higher ...

  15. Facile combustion synthesis of novel CaZrO 3

    Indian Academy of Sciences (India)

    Abstract. A facile sol–gel combustion route was reported for the direct preparation of CaZrO3:Eu3+ and CaZrO3:Eu3+, Gd3+. The obtained deposits were characterized by XRD, TGA-DSC, SEM, EDS, PL measurements and microscope fluorescence. When the Gd3+ ions were introduced in this compound, the emissions of ...

  16. SNL/CA Environmental Management System Program Manual.

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Barbara L.

    2005-09-01

    The Sandia National Laboratories, California (SNL/CA) Environmental Management System (EMS) Program Manual documents the elements of the site EMS Program. The SNL/CA EMS Program was developed in accordance with Department of Energy (DOE) Order 450.1 and incorporates the elements of the International Standard on Environmental Management Systems, ISO 14001.

  17. Isolation and characterization of higher metallofullerenes Ca@C92 ...

    Indian Academy of Sciences (India)

    Administrator

    allofullerenes containing alkaline earth metal ions could be isolated although their relative yields are extremely low. Ca@C92 and Ca@C94 ... laser vapourization of a graphite–metal composite in a helium filled tube oven at high ... robenzene extraction, chlorobenzene and benzene mo- bile phase for isolation of fullerenes ...

  18. Unanimous Model for Describing the Fast Bioluminescence Kinetics of Ca

    NARCIS (Netherlands)

    Eremeeva, Elena V.; Bartsev, Sergey I.; Berkel, van Willem J.H.; Vysotski, Eugene S.

    2017-01-01

    Upon binding their metal ion cofactors, Ca2+-regulated photoproteins display a rapid increase of light signal, which reaches its peak within milliseconds. In the present study, we investigate bioluminescence kinetics of the entire photoprotein family. All five recombinant hydromedusan Ca2+-regulated

  19. 76 FR 45180 - Modification of Class E Airspace; Alturas, CA

    Science.gov (United States)

    2011-07-28

    ...-0403; Airspace Docket No. 11-AWP-3] Modification of Class E Airspace; Alturas, CA AGENCY: Federal... Alturas Municipal Airport, Alturas, CA. Controlled airspace is necessary to accommodate aircraft using... Alturas Municipal Airport. This improves the safety and management of Instrument Flight Rules (IFR...

  20. Characterization of the Ca2+ Channels Involved in the Progesterone ...

    African Journals Online (AJOL)

    There is evidence that intracellular Ca2+ concentration plays significant roles in sperm function such as motility and acrosome reaction. Many calcium channels have been identified in the plasma membrane of sperm. Progesterone (P4) stimulates Ca2+ influx and acrosome reaction in human spermatozoa. The effects of ...

  1. PIK3CA mutant tumors depend on oxoglutarate dehydrogenase

    Science.gov (United States)

    Ilic, Nina; Birsoy, Kıvanç; Aguirre, Andrew J.; Kory, Nora; Pacold, Michael E.; Singh, Shambhavi; Moody, Susan E.; DeAngelo, Joseph D.; Spardy, Nicole A.; Freinkman, Elizaveta; Weir, Barbara A.; Cowley, Glenn S.; Root, David E.; Asara, John M.; Vazquez, Francisca; Widlund, Hans R.; Sabatini, David M.; Hahn, William C.

    2017-01-01

    Oncogenic PIK3CA mutations are found in a significant fraction of human cancers, but therapeutic inhibition of PI3K has only shown limited success in clinical trials. To understand how mutant PIK3CA contributes to cancer cell proliferation, we used genome scale loss-of-function screening in a large number of genomically annotated cancer cell lines. As expected, we found that PIK3CA mutant cancer cells require PIK3CA but also require the expression of the TCA cycle enzyme 2-oxoglutarate dehydrogenase (OGDH). To understand the relationship between oncogenic PIK3CA and OGDH function, we interrogated metabolic requirements and found an increased reliance on glucose metabolism to sustain PIK3CA mutant cell proliferation. Functional metabolic studies revealed that OGDH suppression increased levels of the metabolite 2-oxoglutarate (2OG). We found that this increase in 2OG levels, either by OGDH suppression or exogenous 2OG treatment, resulted in aspartate depletion that was specifically manifested as auxotrophy within PIK3CA mutant cells. Reduced levels of aspartate deregulated the malate–aspartate shuttle, which is important for cytoplasmic NAD+ regeneration that sustains rapid glucose breakdown through glycolysis. Consequently, because PIK3CA mutant cells exhibit a profound reliance on glucose metabolism, malate–aspartate shuttle deregulation leads to a specific proliferative block due to the inability to maintain NAD+/NADH homeostasis. Together these observations define a precise metabolic vulnerability imposed by a recurrently mutated oncogene. PMID:28396387

  2. Purification and biochemical characterization of a Ca2+- ...

    African Journals Online (AJOL)

    On the other hand, Ca+2 and EDTA (1 to 5 mM) did not significantly affect the enzyme activity. The main substrate for the enzyme was found to be starch but it could also hydrolyze raw starch, dextrin, γ-cyclodextrin and pullulan. Key words: Ca2+-independent, Bacillus sp, thermostable α-amylases, low pH profile, enzyme, ...

  3. Purification and characterization of a Ca -dependent/calmodulin ...

    Indian Academy of Sciences (India)

    Unknown

    mitrella patens and Funaria hygrometrica, calcium acts as an intracellular messenger in cytokinin-induced vege- tative bud formation (Schumaker and Gizinski 1995). Calcium-free medium (buffered with EGTA), the extra- cellular Ca2+ antagonist lanthanum (La3+) and the Ca2+ channel inhibitors, D600 and verapamil, ...

  4. Synthesis and microwave dielectric properties of Ca substituted ...

    Indian Academy of Sciences (India)

    Keywords. Patch antenna; theoretical density; phase; ceramics. Abstract. Microwave dielectric ceramics in Sr1-CaLa4Ti4.93Zr0.07O17 (0 ≤ ≤ 0.5) composition series were processed via a solid-state sintering rout. X-ray diffraction revealed single phase ceramics. Ca substitutions for Sr tuned f towards zero with ...

  5. Hierarchic stochastic modelling applied to intracellular Ca(2+ signals.

    Directory of Open Access Journals (Sweden)

    Gregor Moenke

    Full Text Available Important biological processes like cell signalling and gene expression have noisy components and are very complex at the same time. Mathematical analysis of such systems has often been limited to the study of isolated subsystems, or approximations are used that are difficult to justify. Here we extend a recently published method (Thurley and Falcke, PNAS 2011 which is formulated in observable system configurations instead of molecular transitions. This reduces the number of system states by several orders of magnitude and avoids fitting of kinetic parameters. The method is applied to Ca(2+ signalling. Ca(2+ is a ubiquitous second messenger transmitting information by stochastic sequences of concentration spikes, which arise by coupling of subcellular Ca(2+ release events (puffs. We derive analytical expressions for a mechanistic Ca(2+ model, based on recent data from live cell imaging, and calculate Ca(2+ spike statistics in dependence on cellular parameters like stimulus strength or number of Ca(2+ channels. The new approach substantiates a generic Ca(2+ model, which is a very convenient way to simulate Ca(2+ spike sequences with correct spiking statistics.

  6. Maternal serum CA-125 level is elevated in severe preeclampsia.

    Science.gov (United States)

    Karaman, Erbil; Karaman, Yasemin; Alkış, İsmet; Han, Agahan; Yıldırım, Gökhan; Ark, Hasan Cemal

    2014-01-01

    The aim of this study was to determine the relationship between serum concentrations of cancer antigen-125 (CA-125) and pre-eclampsia severity. We evaluated 91 females with a singleton pregnancy. Serum CA-125 levels were measured in subjects with severe pre-eclampsia (n=34) and those with mild pre-eclampsia (n=24). Females with healthy pregnancies (n=31) served as the control group. The three study groups were statistically similar in terms of maternal age, gestational age, and body mass index. The CA-125 level was significantly higher in the severe pre-eclampsia group than that in the mild pre-eclampsia and control groups (pCA-125 levels between the mild pre-eclampsia and control groups was observed. CA-125 level was positively correlated with proteinuria (r=0.489, p=0.000), systolic blood pressure (r=0.503, p=0.018), and diastolic blood pressure (r=0.532, p=0.000). In contrast, CA-125 was negatively correlated with birth weight (r=0.266, p=0.012) and gestational age at birth (r=0.250, p=0.018). CA-125 level increased in severe pre-eclampsia, which reflected abnormal trophoblastic invasion and chronic inflammation. Elevated levels of CA-125 in pre-eclamptic patients may be a marker of the disease severity. Copyright © 2013 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  7. CA1 contributes to microcalcification and tumourigenesis in breast cancer

    International Nuclear Information System (INIS)

    Zheng, Yabing; Xu, Bing; Zhao, Yan; Gu, He; Li, Chang; Wang, Yao; Chang, Xiaotian

    2015-01-01

    Although mammary microcalcification is frequently observed and has been associated with poor survival in patients with breast cancer, the genesis of calcification remains unclear. Carbonic anhydrase I (CA1) has been shown to promote calcification by catalysing the hydration of CO 2 . This study aimed to determine whether CA1 was correlated with microcalcification and with other processes that are involved in breast cancer tumourigenesis. CA1 expression in breast cancer tissues and blood samples was detected using western blotting, real-time PCR, immunohistochemistry and ELISA. Calcification was induced in the cultured 4T1 cell line originating from mouse breast tumours, using ascorbic acid and β-glycerophosphate. Acetazolamide, a chemical inhibitor of CA1, was also added to the culture to determine the role of CA1 in calcification. The MCF-7 human breast cancer cell line was treated with anti-CA1 siRNA and was assessed using a CCK-8 cell proliferation assay, an annexin V cell apoptosis assay, transwell migration assay and a human breast cancer PCR array. The tag SNP rs725605, which is located in the CA1 locus, was genotyped using TaqMan® genotyping. Increased CA1 expression was detected in samples of breast carcinoma tissues and blood obtained from patients with breast cancer. A total of 15.3 % of these blood samples exhibited a 2.1-fold or higher level of CA1 expression, compared to the average level of CA1 expression in samples from healthy controls. Following the induction of calcification of 4T1 cells, both the number of calcium-rich deposits and the expression of CA1 increased, whereas the calcification and CA1 expression were significantly supressed in the presence of acetazolamide. Increased migration and apoptosis were observed in MCF-7 cells that were treated with anti-CA1 siRNA. The PCR array detected up-regulation of the androgen receptor (AR) and down-regulation of X-box binding protein 1 (XBP1) in the treated MCF-7 cells. Significant differences in

  8. CA1 contributes to microcalcification and tumourigenesis in breast cancer.

    Science.gov (United States)

    Zheng, Yabing; Xu, Bing; Zhao, Yan; Gu, He; Li, Chang; Wang, Yao; Chang, Xiaotian

    2015-10-12

    Although mammary microcalcification is frequently observed and has been associated with poor survival in patients with breast cancer, the genesis of calcification remains unclear. Carbonic anhydrase I (CA1) has been shown to promote calcification by catalysing the hydration of CO2. This study aimed to determine whether CA1 was correlated with microcalcification and with other processes that are involved in breast cancer tumourigenesis. CA1 expression in breast cancer tissues and blood samples was detected using western blotting, real-time PCR, immunohistochemistry and ELISA. Calcification was induced in the cultured 4T1 cell line originating from mouse breast tumours, using ascorbic acid and β-glycerophosphate. Acetazolamide, a chemical inhibitor of CA1, was also added to the culture to determine the role of CA1 in calcification. The MCF-7 human breast cancer cell line was treated with anti-CA1 siRNA and was assessed using a CCK-8 cell proliferation assay, an annexin V cell apoptosis assay, transwell migration assay and a human breast cancer PCR array. The tag SNP rs725605, which is located in the CA1 locus, was genotyped using TaqMan® genotyping. Increased CA1 expression was detected in samples of breast carcinoma tissues and blood obtained from patients with breast cancer. A total of 15.3 % of these blood samples exhibited a 2.1-fold or higher level of CA1 expression, compared to the average level of CA1 expression in samples from healthy controls. Following the induction of calcification of 4T1 cells, both the number of calcium-rich deposits and the expression of CA1 increased, whereas the calcification and CA1 expression were significantly supressed in the presence of acetazolamide. Increased migration and apoptosis were observed in MCF-7 cells that were treated with anti-CA1 siRNA. The PCR array detected up-regulation of the androgen receptor (AR) and down-regulation of X-box binding protein 1 (XBP1) in the treated MCF-7 cells. Significant differences in

  9. Quantifying Ca2+ release and inactivation of Ca2+ release in fast- and slow-twitch muscles

    Science.gov (United States)

    Barclay, C J

    2012-01-01

    The aims of this study were to quantify the Ca2+ release underlying twitch contractions of mammalian fast- and slow-twitch muscle and to comprehensively describe the transient inactivation of Ca2+ release following a stimulus. Experiments were performed using bundles of fibres from mouse extensor digitorum longus (EDL) and soleus muscles. Ca2+ release was quantified from the amount of ATP used to remove Ca2+ from the myoplasm following stimulation. ATP turnover by crossbridges was blocked pharmacologically (N-benzyl-p-toluenesulphonamide for EDL, blebbistatin for soleus) and muscle heat production was used as an index of Ca2+ pump ATP turnover. At 20°C, Ca2+ release in response to a single stimulus was 34 and 84 μmol (kg muscle)−1 for soleus and EDL, respectively, and increased with temperature (30°C: soleus, 61 μmol kg−1; EDL, 168 μmol kg−1). Delivery of another stimulus within 100 ms of the first produced a smaller Ca2+ release. The maximum magnitude of the decrease in Ca2+ release was greater in EDL than soleus. Ca2+ release recovered with an exponential time course which was faster in EDL (mean time constant at 20°C, 32.1 ms) than soleus (65.6 ms) and faster at 30°C than at 20°C. The amounts of Ca2+ released and crossbridge cycles performed are consistent with a scheme in which Ca2+ binding to troponin-C allowed an average of ∼1.7 crossbridge cycles in the two muscles. PMID:23027818

  10. Spin decomposition of the responses of 44Ca and 48Ca to 300 MeV protons

    International Nuclear Information System (INIS)

    Baker, F.T.; Bimbot, L.; Fergerson, R.W.; Glashausser, C.; Green, A.; Haeusser, O.; Hicks, K.; Jones, K.; Miller, C.A.; Vetterli, M.; Abegg, R.; Beatty, D.; Bonin, B.; Castel, B.; Chen, X.Y.; Cupps, V.; Djalali, C.; Henderson, R.; Jackson, K.P.; Jeppesen, R.; Nakayama, K.; Nanda, S.K.; Sawafta, R.; Yen, S.; Institut de Physique Nucleaire, F-91406 Orsay, France; Rutgers University, Piscataway, New Jersey 08854; Simon Fraser University, Burnaby, Canada V5A1S6; TRIUMF, 4004 Westbrook Mall, Vancouver, Canada V6T2A3; Los Alamos National Laboratory, Los Alamos, New Mexico 87544; Centre d'Etudes Nucleaires de Saclay, 91191 Gif sur Yvette, CEDEX, France; Queen's University, Kingston, Canada K7L3N6; University of Colorado, Boulder, Colorado 80309; University of South Carolina, Columbia, South Carolina 29208; Continuous Electron Beam Accelerator Facility, 12000 Jefferson Ave., Newport News, Virginia 23606; University of Alberta, Edmonton, Canada T6G2J1)

    1991-01-01

    Angular distributions of the double-differential cross section d 2 σ/dΩ dE(σ) and the spin-flip probability S nn have been measured for inclusive proton inelastic scattering from 44 Ca at 290 MeV and from 48 Ca at 318 MeV. Excitation energies up to about 50 MeV for 44 Ca and 40 MeV for 48 Ca have been investigated over the laboratory angular ranges of 3 degree to 12 degree for 44 Ca and 3 degree to 9 degree for 48 Ca. Multipole decompositions of angular distributions of both the spin-flip cross section σS nn and the estimated cross section for ΔS=0 transitions have been performed. Distributions of strengths were deduced for ΔL=1, ΔS=0 (the giant dipole), ΔL=2, ΔS=0 (the giant quadrupole), ΔL=0, ΔS=1 (the magnetic dipole), ΔL=1, ΔS=1 (the spin dipole), and ΔL=2, ΔS=1 (the spin quadrupole). The ΔS=0 summed strengths for 44 Ca are lower than for 40 Ca and 48 Ca. The spin-dipole summed strengths are found to be approximately independent of A. For 48 Ca, essentially all M1 strength observed was in the 10.23 MeV 1 + state; for 44 Ca, M1 strength was observed to be fragmented over a range of 7 to 18 Mev

  11. Microstructure, In Vitro Corrosion Behavior and Cytotoxicity of Biodegradable Mg-Ca-Zn and Mg-Ca-Zn-Bi Alloys

    Science.gov (United States)

    Bakhsheshi-Rad, H. R.; Hamzah, E.; Tok, H. Y.; Kasiri-Asgarani, M.; Jabbarzare, S.; Medraj, M.

    2017-02-01

    The effects of bismuth (Bi) addition on the microstructure and corrosion behavior of the Mg-Ca-Zn-Bi alloys were evaluated using electron microscopy, electrochemical test and electrochemical impedance spectroscopy. Microstructural observations showed that Mg-1.2Ca-1Zn- xBi ( x = 0.5, 1.5, 3 wt.%) are composed of Mg2Ca, Ca2Mg6Zn3 and Mg3Bi2 phases while a new phase Mg2Bi2Ca appeared after the addition of 5 and 12 wt.% Bi to the Mg-1.2Ca-1Zn alloy. Furthermore, the additions of 0.5 wt.% Bi to the Mg-1.2Ca-1Zn alloy slightly improved the corrosion behavior of the alloy, while further increase in Bi amount from 1.5 to 12 wt.% has a deleterious effect on the corrosion behavior of the ternary Mg-1.2Ca-1Zn alloy which is driven by galvanic coupling effect. Cytotoxicity tests indicate that the Mg-1.2Ca-1Zn presents higher cell viability compared to Mg-1.2Ca-1Zn-0.5Bi alloy. In addition, the cell viability of both alloys increased with increasing incubation time while diluting the extracts to 50% and 10% improved the cell viabilities. The present results suggest that the Mg-1.2Ca-1Zn-0.5Bi can be interesting candidate for the development of degradable biomaterials and it is worthwhile for further investigation in an in vivo environment.

  12. Assessment of diagnostic value of various tumors markers (CEA, CA199, CA50) for colorectal neoplasm with logistic regression and ROC curve

    International Nuclear Information System (INIS)

    Gu Ping; Huang Gang; Han Yuan

    2007-01-01

    Objective: To assess the diagnostic value of CEA, CA199 and CA50 for colorectal neoplasm by logistic regression and ROC curve. Methods: Serum CEA (with CLIA), CA199 (with ECLIA) and CA50 (with IRMA) levels were measured in 75 patients with colorectal cancer, 35 patients with benign colorectal disorders and 49 controls. The area under the ROC curve (AUC)s of CEA, CA199, CA50 from logistic regression results were compared. Results: In the cancer-benign disorder group, the AUC of CA50 was larger than the AUC of CA199. AUC of combined CEA, CA50 was largest: not only larger than any AUC of CEA, CA50, CA199 alone but also larger than the AUC of the combined three markers (0.875 vs 0.604). In cancer-control group, the AUC of combination of CEA, CA199 and CA50 was larger than any AUC of CEA, CA199 or CA50 alone. Both in the cancer-benign disorder group or cancer-control group, the AUC of CEA was larger than the AUC of CA199 or CA50. Conclusion: CEA is of definite value in the diagnosis of colorectal cancer. For differential diagnosis, the combination of CEA and CA50 can give more information, while the combination of three tumor markers is less helpful. As an advanced statistical method, logistic regression can improve the diagnostic sensitivity and specificity. (authors)

  13. Ca2+-dependent K+ Channels in Exocrine Salivary Glands

    Science.gov (United States)

    Catalán, Marcelo A.; Peña-Munzenmayer, Gaspar; Melvin, James E.

    2014-01-01

    In the last 15 years, remarkable progress has been realized in identifying the genes that encode the ion-transporting proteins involved in exocrine gland function, including salivary glands. Among these proteins, Ca2+-dependent K+ channels take part in key functions including membrane potential regulation, fluid movement and K+ secretion in exocrine glands. Two K+ channels have been identified in exocrine salivary glands: 1) a Ca2+-activated K+ channel of intermediate single channel conductance encoded by the KCNN4 gene; and, 2) a voltage- and Ca2+-dependent K+ channel of large single channel conductance encoded by the KCNMA1 gene. This review focuses on the physiological roles of Ca2+-dependent K+ channels in exocrine salivary glands. We also discuss interesting recent findings on the regulation of Ca2+-dependent K+ channels by protein-protein interactions that may significantly impact exocrine gland physiology. PMID:24559652

  14. Proton resonance spectroscopy in 40Ca

    International Nuclear Information System (INIS)

    Warthen, B.J.

    1987-01-01

    The differential cross sections for the 39 K(p,p o ) 39 K and 39 K-(p,α o ) 36 Ar reactions have been measured for E p = 1.90 to 4.02 MeV at laboratory angles θ = 90 degree, 108 degree, 150 degree and 165 degree. Data were taken with the Triangle Universities Nuclear Laboratory (TUNL) KN Van de Graaff accelerator and the associated high resolution system. The targets consisted of 1-2 μg/cm 2 of potassium carbonate (K 2 CO 3 ), enriched to 99.97% 39 K, evaporated onto gold coated carbon backings. Excitation functions were measured in proton energy steps varying from 100 to 400 3V. The energy region studied corresponds to an excitation energy range in the 40 Ca nucleus of E x = 10.2 to 12.3 MeV. A multi-level multi-channel R-matrix based computer code was used to fit the experimental excitation functions. Resonance parameters obtained include resonance energy, spin, parity, partial widths, and channel spin and orbital angular momentum mixing ratios. Of the 248 resonances observed in the proton channel, 148 were also observed in the alpha channel. A fit to the observed level density yielded a nuclear temperature of 1.5 MeV. The data were compared with predictions of statistical theories of energy levels for both level spacing and reduced width distributions. The alpha reduced widths agree with the Porter-Thomas distribution and suggest that only 5-10% of the states with alpha widths were not observed. The summed strength in each of the alpha channels represents a significant fraction of the Wigner limit for these channels. The proton channels, on the other hand, generally have much smaller fractions. The two proton s-wave strength functions are equal and thus show no evidence for spin-exchange forces in the nucleon-nucleus interaction

  15. Modelling Ca2+ bound Troponin in Excitation Contraction Coupling

    Directory of Open Access Journals (Sweden)

    Henry G. Zot

    2016-09-01

    Full Text Available To explain disparate decay rates of cytosolic Ca2+ and structural changes in the thin filaments during a twitch, we model the time course of Ca2+ bound troponin (Tn resulting from the free Ca2+ transient of fast skeletal muscle. In fibers stretched beyond overlap, the decay of Ca2+ as measured by a change in fluo 3 fluorescence is significantly slower than the intensity decay of the meridional 1/38.5 nm-1 reflection of Tn; this is not simply explained by considering only the Ca2+ binding properties of Tn alone (Matsuo, T., Iwamoto, H., and Yagi, N. (2010. Biophys. J. 99, 193-200. We apply a comprehensive model that includes the known Ca2+ binding properties of Tn in the context of the thin filament with and without cycling crossbridges. Calculations based on the model predict that the transient of Ca2+ bound Tn correlates with either the fluo 3 time course in muscle with overlapping thin and thick filaments or the intensity of the meridional 1/38.5 nm-1 reflection in overstretched muscle. Hence, cycling crossbridges delay the dissociation of Ca2+ from Tn. Correlation with the fluo 3 fluorescence change is not causal given that the transient of Ca2+ bound Tn depends on sarcomere length, whereas the fluo-3 fluorescence change does not. Transient positions of tropomyosin calculated from the time course of Ca2+ bound Tn are in reasonable agreement with the transient of measured perturbations of the Tn repeat in overlap and non-overlap muscle preparations.

  16. Ca(2+)-dependence of conoid extrusion in Toxoplasma gondii tachyzoites.

    Science.gov (United States)

    Mondragon, R; Frixione, E

    1996-01-01

    The role of Ca2+ in conoid extrusion was investigated in isolated Toxoplasma gondii tachyzoites by treatment with Ca(2+)-ionophores, Ca(2+)-chelating agents and an inhibitor of the Ca(2+)-ATPase at the endoplasmic reticulum. The results were evaluated by light phase-contrast microscopy and electron microscopy. Ionomycin (0.5-1 microM) caused an immediate and sustained extrusion of the conoid in up to 80% of the tachyzoites, depending on the concentrations of ionophore and Ca2+ in the medium. However, over 50% of the tachyzoites extruded the conoid when treated with ionomycin in Ca(2+)-free saline complemented with EGTA. The effect of ionomycin was reversible and could be induced a second time in about half of the responsive population. Similar results were obtained with A23187. Conoid extrusion induced by ionomycin in Ca(2+)-free medium was almost completely abolished when the tachyzoites were previously loaded with a permeable compound known to chelate intracellular Ca2+ (BAPTA/AM; 25 microM). On the other hand, exposure of tachyzoites to the Ca(2+)-ATPase inhibitor thapsigargin (0.5-1 microM) produced significant extrusion of the conoid. Tachyzoites loaded with BAPTA/AM as well as those treated with ionomycin, i.e. with conoids paralyzed in opposite positions, had a diminished capacity to invade cultured epithelial cells. A substantial reduction in the response to stimulation by ionomycin was found also in parasites treated with cytochalasin-D, a drug that depolymerizes actin-filaments. The results suggest that Ca(2+)-release from internal stores may act as a key signal to activate a mechanism of conoid extrusion probably mediated, at least in part, by actin-filaments.

  17. Up-regulation of Ca2+/CaMKII/CREB signaling in salicylate-induced tinnitus in rats.

    Science.gov (United States)

    Zhao, Jiuhan; Wang, Biao; Wang, Xiaohong; Shang, Xiuli

    2018-02-09

    The purpose of the study was to investigate the changes of Ca 2+ /calmodulin-dependent protein kinases II (CaMKII)/cAMP response element-binding protein (CREB) signaling pathway in a rat tinnitus model. Eighteen Wistar rats were randomly divided into three groups: normal control (NC), normal saline (NS), and tinnitus model (TM) groups. Tinnitus model was induced by intraperitoneal injection of salicylate. The concentration of intracellular calcium level in auditory cortex cells was determined using Fura-2 acetoxymethyl ester (Fura-2 AM) method with fluorospectrophotometer. Expressions of calmodulin (CaM), N-methyl-D-aspartate receptor 2B subunit (NR2B), calcium-calmodulin kinase II (CaMKII), and cAMP response element-binding protein (CREB) were detected with Western blot. Tinnitus model was successfully established by the intraperitoneal administration of salicylate in rats. Compared with rats in NC and NS groups, salicylate administration significantly elevated CaM, NR2B, phospho-CaMKII and phospho-CREB expression in auditory cortex from tinnitus model group (p salicylate administration causes tinnitus symptoms and elevates Ca 2+ /CaMKII/CREB signaling pathway in auditory cortex cells. Our study likely provides a new understanding of the development of tinnitus.

  18. 45Ca2+movements induced by Ca2+chloride in isolated rat aorta under K+-free conditions

    NARCIS (Netherlands)

    Wermelskirchen, D.; Nebel, U.; Wirth, A.; Wilffert, B.

    1991-01-01

    Increasing the extracellular Ca2+concentration induced a dihydropyridine-insensitive contraction in the isolated rat aorta bathed in K+-free solution. To obtained further insight into the mechanisms of this contraction45Ca2+uptake measurements were carried out with isolated rat aorta. Increasing the

  19. CA-45(2+) MOVEMENTS INDUCED BY CA2+ CHLORIDE IN ISOLATED RAT AORTA UNDER K+-FREE CONDITIONS

    NARCIS (Netherlands)

    WERMELSKIRCHEN, D; NEBEL, U; WIRTH, A; WILFFERT, B

    1991-01-01

    Increasing the extracellular Ca2+ concentration induced a dihydropyridine-insensitive contraction in the isolated rat aorta bathed in K+-free solution. To obtain further insight into the mechanism of this contraction Ca-45(2+) uptake measurements were carried out with isolated rat aorta. Increasing

  20. Acrosome Reaction and Ca2+ Imaging in Single Human Spermatozoa: New Regulatory Roles of [Ca2+]i1

    Science.gov (United States)

    Sánchez-Cárdenas, Claudia; Servín-Vences, Martha Rocio; José, Omar; Treviño, Claudia Lydia; Hernández-Cruz, Arturo; Darszon, Alberto

    2014-01-01

    ABSTRACT The spermatozoa acrosome reaction (AR) is essential for mammalian fertilization. Few methods allow visualization of AR in real time together with Ca2+ imaging. Here, we show that FM4-64, a fluorescent dye used to follow exocytosis, reliably reports AR progression induced by ionomycin and progesterone in human spermatozoa. FM4-64 clearly delimits the spermatozoa contour and reports morphological cell changes before, during, and after AR. This strategy unveiled the formation of moving tubular appendages, emerging from acrosome-reacted spermatozoa, which was confirmed by scanning electron microscopy. Alternate wavelength illumination allowed concomitant imaging of FM4-64 and Fluo-4, a Ca2+ indicator. These AR and intracellular Ca2+ ([Ca2+]i) recordings revealed that the presence of [Ca2+]i oscillations, both spontaneous and progesterone induced, prevents AR in human spermatozoa. Notably, the progesterone-induced AR is preceded by a second [Ca2+]i peak and ∼40% of reacting spermatozoa also manifest a slow [Ca2+]i rise ∼2 min before AR. Our findings uncover new AR features related to [Ca2+]i. PMID:25100708

  1. Characterization of Ca2+ Signalling in Postnatal Mouse Retinal Ganglion Cells: Involvement of OPA1 in Ca2+ Clearance

    Czech Academy of Sciences Publication Activity Database

    Dayanithi, Govindan; Chen-Kuo-Chang, M.; Viero, C.; Hamel, C.; Muller, A.; Lenaers, G.

    2010-01-01

    Roč. 31, č. 2 (2010), s. 53-65 ISSN 1381-6810 Institutional research plan: CEZ:AV0Z50390703 Keywords : retinal ganglion cells * Ca2+ homeostasis * Ca2+ clearance Subject RIV: FH - Neurology Impact factor: 1.333, year: 2010

  2. Serum CA 125, carcinoembryonic antigen, and CA 19-9 as tumor markers in borderline ovarian tumors

    NARCIS (Netherlands)

    Engelen, MJA; de Bruijn, HWA; Hollema, H; ten Koor, KA; Willemse, PHB; Aalders, JG; van der Zee, AGJ

    Objectives. The goals of this study were to analyze preoperative serum levels of CA 125, carcinoembryonic antigen (CEA), and CA 19-9 in patients with borderline ovarian tumors and to investigate if routine assessment of these markers in follow-up may lead to earlier detection of recurrence. Methods.

  3. Thermoelectric properties of antiperovskite calcium oxides Ca3PbO and Ca3SnO

    Science.gov (United States)

    Okamoto, Y.; Sakamaki, A.; Takenaka, K.

    2016-05-01

    We report the thermoelectric properties of polycrystalline samples of Ca3Pb1-xBixO (x = 0, 0.1, 0.2) and Ca3SnO, both crystallizing in a cubic antiperovskite-type structure. The Ca3SnO sample shows metallic resistivity and its thermoelectric power approaches 100 μV K-1 at room temperature, resulting in the thermoelectric power factor of Ca3SnO being larger than that of Ca3Pb1-xBixO. On the basis of Hall and Sommerfeld coefficients, the Ca3SnO sample is found to be a p-type metal with a carrier density of ˜1019 cm-3, a mobility of ˜80 cm2 V-1 s-1, both comparable to those in degenerated semiconductors, and a moderately large hole carrier effective mass. The coexistence of moderately high mobility and large effective mass observed in Ca3SnO, as well as possible emergence of a multivalley electronic structure with a small band gap at low-symmetry points in k-space, suggests that the antiperovskite Ca oxides have strong potential as a thermoelectric material.

  4. Solidification and Immobilization of Heavy metals in Soil using with nano-metallic Ca/CaO Dispersion Mixture

    Directory of Open Access Journals (Sweden)

    Mallampati S. R.

    2013-04-01

    Full Text Available In the present work, the use of nano-metallic calcium (Ca and calcium oxide (CaO dispersion mixture for the immobilization of heavy metals (As, Cd, Cr and Pb in soil was investigated. With simple grinding, 85-90% of heavy metals immobilization could be achieved, while it could be enhanced to 98-100% by grinding with the addition of nano-metallic Ca/CaO dispersion mixture. By SEM-EDS elemental maps as well as semi-quantitative analysis observed that the amount of As, Cd, Cr and Pb measurable on soil particle surface decreases after nano-metallic Ca/CaO treatment. The leachable heavy metals concentrations were reduced, to the concentration lower than the Japan soil elution standard regulatory threshold, i. e., < 0.01 mg/l for As, Cd and Pb and 0.05mg/l for Cr. Whereas, the effect of soil moisture and pH on heavy metals immobilization was not much influenced. The results suggest that nano-metallic Ca/CaO mixture is suitable to be used for the gentle immobilization of heavy metals contaminated soil at normal moisture conditions.

  5. The effects of CaCl2 and CaBr2 on the reproduction of Daphnia magna Straus.

    Science.gov (United States)

    Mažuran, Neda; Hršak, Vladimir; Kovačević, Goran

    2015-06-01

    Concentrated CaCl2 and CaBr2 salt solutions of densities up to 2.3 kg L-1 are regularly used to control hydrostatic pressure in oil wells during special operations in the exploration and production of natural gas and crude oil. Various concentrations of high density salts are frequently left in mud pits near the drilling site as waste, polluting fresh and ground waters by spillage and drainage. The toxic effects of these salts have already been observed. This study investigated the effects of CaCl2 and CaBr2 on water flea Daphnia magna Straus in a 21-day reproduction test. The three tested concentrations of CaCl2 (240, 481, and 1925 mg L-1) caused a significant dose-response decrease of reproduction (psubstance. The results suggest that high concentrations of the tested chemicals are harmful to Daphnia's reproduction and could reduce its abundance.

  6. Expression of PIK3CA, PTEN mRNA and PIK3CA mutations in primary breast cancer

    DEFF Research Database (Denmark)

    Palimaru, Irina; Brügmann, Anja; Wium-Andersen, Marie Kim

    2013-01-01

    suppressor, phosphatase and tensin homolog (PTEN), in breast carcinoma tissue and normal breast tissue. Furthermore, we examine whether expression of PIK3CA and PTEN mRNA and occurrence of PIK3CA mutations are associated with lymph node metastases in patients with primary breast cancer. METHODS: Paired...... tissue samples of breast carcinoma and normal breast tissue were obtained from 175 breast cancer patients at the time of primary surgery, of these 105 patients were lymph node positive. Expression of PIK3CA and PTEN mRNA was quantified with Quantitative Real Time PCR. Somatic mutations in exon 9 and exon...... 20 of the PIK3CA gene were identified by genotyping. RESULTS: Both PIK3CA and PTEN mRNA expression was significantly increased in breast carcinoma tissue compared to normal breast tissue (p = 2 × 10(-11)) and (p 

  7. Neutron-scattering studies of the doubly magic Ca nuclei, 40Ca and 48Ca, in the low-energy resonance region

    International Nuclear Information System (INIS)

    Hicks, S.F.

    1988-01-01

    Measurements of neutron elastic and inelastic scattering differential cross sections from 48 Ca at 2.35, 2.43, 2.71, 3.15, 3.55, 4.70, 6.00, and 7.97 MeV are presented. These data are combined with n + 48 Ca total cross sections taken at Oak Ridge National Laboratory to form a rather extensive set of scattering data for 48 Ca between 80 keV and 20 MeV incident neutron energy. Coupled-channels analyses of these data with a first-order vibrational model described both the neuron inelastic cross sections at 7.97 MeV and intermediate structure resonances observed in the total cross sections below 3 MeV. Particle-core coupled resonance configurations were determined for four intermediate structure resonances from the coupled-channels calculations. Also measured at each of the energies listed above were neutron elastic and inelastic cross sections from 40 Ca. In addition to the above coupled-channels analysis of 48 Ca, the mean field potential used to describe the bound-state and scattering data of 48 Ca was determined using a dispersion relation to connect the real and imaginary components of the optical model potential. Finally, differential scattering cross sections measured between 2 and 3.5 MeV from 48 Ca are compared to calculations using phase shifts from an evaluation of the total cross sections. The agreement between the measured and calculated differential scattering cross sections was excellent at some energies

  8. Mechanical and thermal-expansion characteristics of Ca10(PO46(OH2-Ca3(PO42 composites

    Directory of Open Access Journals (Sweden)

    Ruseska G.

    2006-01-01

    Full Text Available Three types of composites consisting of Ca10(PO46(OH2 and Ca3(PO42 with composition: 75% (wt Ca10(PO46(OH2: 25%(wt Ca3(PO42; 50%(wt Ca10(PO46(OH2: 50%(wtCa3(PO42 and 25 %(wt Ca10(PO46(OH2: 75%(wt Ca3(PO42 were the subject of our investigation. Sintered compacts were in thermal equilibrium, which was proved by the absence of hysteresis effect of the dependence ΔL/L=f(T during heating /cooling in the temperature interval 20-1000-200C. Sintered compacts with the previously mentioned composition possess 26-50% higher values of the E-modulus, G-modulus and K-modulus indicating the presence of a synergism effect. Several proposed model equations for predicting the thermal expansion coefficient in dependence of the thermal and elastic properties of the constitutive phases and their volume fractions, given by: Turner, Kerner, Tummala and Friedberg, Thomas and Taya, were used for making correlations between mechanical and thermal-expansion characteristics of the Ca10(PO46(OH2 - Ca3(PO42 composites. Application of the previously mentioned model equations to all kinds of composites leads to the conclusion that the experimentally obtained results for the thermal expansion coefficient are in an excellent agreement with the theoretical calculated values on account of the volume fraction of each constitutive phase and with all applied model equations, with a coefficient of correlation from 98.16-99.86 %.

  9. Clinical value of preoperative serum CA 19-9 and CA 125 levels in predicting the resectability of hilar cholangiocarcinoma.

    Science.gov (United States)

    Hu, Hai-Jie; Mao, Hui; Tan, Yong-Qiong; Shrestha, Anuj; Ma, Wen-Jie; Yang, Qin; Wang, Jun-Ke; Cheng, Nan-Sheng; Li, Fu-Yu

    2016-01-01

    To examine the predictive value of tumor markers for evaluating tumor resectability in patients with hilar cholangiocarcinoma and to explore the prognostic effect of various preoperative factors on resectability in patients with potentially resectable tumors. Patients with potentially resectable tumors judged by radiologic examination were included. The receiver operating characteristic (ROC) analysis was conducted to evaluate serum carbohydrate antigenic determinant 19-9 (CA 19-9), carbohydrate antigen 125 (CA 125) and carcino embryonie antigen levels on tumor resectability. Univariate and multivariate logistic regression models were also conducted to analysis the correlation of preoperative factors with resectability. In patients with normal bilirubin levels, ROC curve analysis calculated the ideal CA 19-9 cut-off value of 203.96 U/ml in prediction of resectability, with a sensitivity of 83.7 %, specificity of 80 %, positive predictive value of 91.1 % and negative predictive value of 66.7 %. Meanwhile, the optimal cut-off value for CA 125 to predict resectability was 25.905 U/ml (sensitivity, 78.6 %; specificity, 67.5 %). In a multivariate logistic regression model, tumor size ≤3 cm (OR 4.149, 95 % CI 1.326-12.981, P = 0.015), preoperative CA 19-9 level ≤200 U/ml (OR 20.324, 95 % CI 6.509-63.467, P CA 125 levels ≤26 U/ml (OR 8.209, 95 % CI 2.624-25.677, P CA 19-9 and CA 125 levels predict resectability in patients with radiological resectable hilar cholangiocarcinoma. Increased preoperative CA 19-9 levels and CA 125 levels are associated with poor resectability rate.

  10. Ca intercalated bilayer graphene as a thinnest limit of superconducting C6Ca

    Science.gov (United States)

    Kanetani, Kohei; Sugawara, Katsuaki; Sato, Takafumi; Shimizu, Ryota; Iwaya, Katsuya; Hitosugi, Taro; Takahashi, Takashi

    2012-01-01

    Success in isolating a 2D graphene sheet from bulky graphite has triggered intensive studies of its physical properties as well as its application in devices. Graphite intercalation compounds (GICs) have provided a platform of exotic quantum phenomena such as superconductivity, but it is unclear whether such intercalation is feasible in the thinnest 2D limit (i.e., bilayer graphene). Here we report a unique experimental realization of 2D GIC, by fabricating calcium-intercalated bilayer graphene C6CaC6 on silicon carbide. We have investigated the structure and electronic states by scanning tunneling microscopy and angle-resolved photoemission spectroscopy. We observed a free-electron–like interlayer band at the Brillouin-zone center, which is thought to be responsible for the superconductivity in 3D GICs, in addition to a large π* Fermi surface at the zone boundary. The present success in fabricating Ca-intercalated bilayer graphene would open a promising route to search for other 2D superconductors as well as to explore its application in devices. PMID:23139407

  11. On Contending with Unruly Neighbors in the Global Village: Viewing Information Systems as Both Weapon and Target

    Science.gov (United States)

    2011-04-01

    user or its intended beneficiary, the practice and the technology are coextensive; the technology becomes ―ready-to-hand‖ [ Heidegger , 1962], an...current Jan. 14, 2011). Heidegger , M. (1962) Being and Time, San Francisco, CA: Harper. Higgins, A., K. Leggett, and A. Cullison (2002) ―How al Qaeda

  12. Changes to a CA Programme - Practitioners' Perspectives

    Directory of Open Access Journals (Sweden)

    Elizabeth Wheeler

    2014-03-01

    Full Text Available This paper examines the perceptions of practitioners of the new directions taken by NZICA with respect to its academic and professional programme requirements to obtain CA Institute membership. The “future viability of any professional body is dependent on continuously attracting new members, ideally the best and the brightest new tertiary graduates”, and this is “undoubtedly the case for New Zealand’s professional accounting body, the New Zealand Institute of Chartered Accountants (NZICA” (Malthus & Fowler 2009, p. 26. In this study, the concurrent triangulation approach to mixed methods described by Creswell (2009 was used to collect data. This approach enabled the results of the two quantitative and qualitative databases to be integrated and compared. It was found that accounting practitioners felt the changes made by NZICA may devalue the brand, while the reduction in liberal papers would result in a narrower degree. Overall, accounting practitioners agreed that three to four years of tertiary accounting education was adequate, a broader four-year course would result in a better-rounded graduates. The reduction in the length of the tertiary programme caused concern that future graduates would be less mature. Accounting practitioners also felt that the changes would harm the credibility of NZICA internationally. However, some accounting practitioners did welcome the fact that the NZICA membership requirements will be more aligned with Institute of Chartered Accountants Australia. Accounting practitioners felt that the new technical modules would offer more flexibility. They believed that the four technical modules should repeat the material taught at university, as long as a balance was maintained between technical and practical skills. They also believed that the changes would result in an increased onus on the employer. Additionally, accounting practitioners agreed that on-the-job training should not replace a tertiary

  13. Shock Compression Response of Calcium Fluoride (CaF2)

    Science.gov (United States)

    Root, Seth

    2017-06-01

    The fluorite crystal structure is a textbook lattice that is observed for many systems, such as CaF2, Mg2 Si, and CeO2. Specifically, CaF2 is a useful material for studying the fluorite system because it is readily available as a single crystal. Under static compression, CaF2 is known to have at least three solid phases: fluorite, cotunnite, and a Ni2 In phase. Along the Hugoniot CaF2 undergoes a fluorite to cotunnite phase transition, however, at higher shock pressures it is unknown whether CaF2 undergoes another solid phase transition or melts directly from the cotunnite phase. In this work, we conducted planar shock compression experiments on CaF2 using Sandia's Z-machine and a two-stage light gun up to 900 GPa. In addition, we use density functional theory (DFT) based quantum molecular dynamics (QMD) simulations to provide insight into the CaF2 state along the Hugoniot. In collaboration with: Michael Desjarlais, Ray Lemke, Patricia Kalita, Scott Alexander, Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL850.

  14. Study of 51Ca via three-neutron transfer

    International Nuclear Information System (INIS)

    Catford, W.N.; Fifield, L.K.; Ophel, T.R.; Orr, N.A.; Weisser, D.C.; Woods, C.L.

    1988-09-01

    Low-lying levels in 51 Ca have been studied via the reaction 48 Ca( 18 O, 15 O) 51 Ca at a beam energy of 108 MeV. Recoiling 51 Ca nuclei were detected in coincidence with 15 O ejectiles, largely removing the substantial background from target contaminants that was encountered in previous work. The lowest 51C a level identified is 1.01 ± 0.11 MeV less bound than the ground state, according to a recent measurement of the ground state mass using the 48 Ca( 14 C, 11 C) 51 Ca reaction. Considerations of the difficulty in identifying the ground state peak suggest that published values of the mass excess should be viewed with caution, and that a definitive mass measurement is still required in order to resolve questions on the structure of the neutron rich calcium isotopes. A total of six energy levels in 51 Ca have been identified and their mass excesses measured. Only two of these levels have been observed previously, via the ( 14 C, 11 C) reaction. Striking differences in selectivity between the ( 18 O, 15 O) and ( 14 C, 11 C) transfer reactions are discussed

  15. Ca2+ signalling early in evolution--all but primitive.

    Science.gov (United States)

    Plattner, Helmut; Verkhratsky, Alexei

    2013-05-15

    Early in evolution, Ca(2+) emerged as the most important second messenger for regulating widely different cellular functions. In eukaryotic cells Ca(2+) signals originate from several sources, i.e. influx from the outside medium, release from internal stores or from both. In mammalian cells, Ca(2+)-release channels represented by inositol 1,4,5-trisphosphate receptors and ryanodine receptors (InsP3R and RyR, respectively) are the most important. In unicellular organisms and plants, these channels are characterised with much less precision. In the ciliated protozoan, Paramecium tetraurelia, 34 molecularly distinct Ca(2+)-release channels that can be grouped in six subfamilies, based on criteria such as domain structure, pore, selectivity filter and activation mechanism have been identified. Some of these channels are genuine InsP3Rs and some are related to RyRs. Others show some--but not all--features that are characteristic for one or the other type of release channel. Localisation and gene silencing experiments revealed widely different--yet distinct--localisation, activation and functional engagement of the different Ca(2+)-release channels. Here, we shall discuss early evolutionary routes of Ca(2+)-release machinery in protozoa and demonstrate that detailed domain analyses and scrutinised functional analyses are instrumental for in-depth evolutionary mapping of Ca(2+)-release channels in unicellular organisms.

  16. Aerobic Hydrogen Production via Nitrogenase in Azotobacter vinelandii CA6

    Science.gov (United States)

    Noar, Jesse; Loveless, Telisa; Navarro-Herrero, José Luis; Olson, Jonathan W.

    2015-01-01

    The diazotroph Azotobacter vinelandii possesses three distinct nitrogenase isoenzymes, all of which produce molecular hydrogen as a by-product. In batch cultures, A. vinelandii strain CA6, a mutant of strain CA, displays multiple phenotypes distinct from its parent: tolerance to tungstate, impaired growth and molybdate transport, and increased hydrogen evolution. Determining and comparing the genomic sequences of strains CA and CA6 revealed a large deletion in CA6's genome, encompassing genes related to molybdate and iron transport and hydrogen reoxidation. A series of iron uptake analyses and chemostat culture experiments confirmed iron transport impairment and showed that the addition of fixed nitrogen (ammonia) resulted in cessation of hydrogen production. Additional chemostat experiments compared the hydrogen-producing parameters of different strains: in iron-sufficient, tungstate-free conditions, strain CA6's yields were identical to those of a strain lacking only a single hydrogenase gene. However, in the presence of tungstate, CA6 produced several times more hydrogen. A. vinelandii may hold promise for developing a novel strategy for production of hydrogen as an energy compound. PMID:25911479

  17. Abnormal CA-125 levels in menopausal women without ovarian cancer.

    Science.gov (United States)

    Terada, Keith Y; Elia, Jennifer; Kim, Robert; Carney, Michael; Ahn, Hyeong Jun

    2014-10-01

    To determine if an abnormal CA-125 level in a menopausal female without ovarian cancer is associated with an increase in mortality. The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Randomized Controlled (PLCO) Trial is a large multicenter prospective trial conducted by the National Cancer Institute (NCI). Over 78,000 healthy women aged 55-74 were randomized to a screening arm versus a usual medical care arm to evaluate the efficacy of screening in reducing mortality due to ovarian cancer. Women in the screening arm underwent annual screening for ovarian cancer with transvaginal ultrasound and CA-125 levels. There were 38,818 patients without ovarian cancer that had at least one CA-125 level drawn; 1201 (3.09%) had at least one abnormal level. The current study compares mortality in patients that had one or more abnormal CA-125 levels without ovarian cancer versus those with all normal levels. Patients with one or more abnormal CA-125 levels, without ovarian cancer, had a significantly higher mortality than patients with all normal CA-125 levels in the PLCO screening trial (pCA-125 and without ovarian cancer are exposed to an increased risk of premature mortality. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Menstrual Cycle Dependent Variability for Serum Tumor Markers CEA, AFP, CA 19-9, CA 125 and CA 15-3 in Healthy Women

    Directory of Open Access Journals (Sweden)

    Ayşe Binnur Erbağci

    1999-01-01

    Full Text Available Information on menstrual cycle dependent variation of tumor markers in healthy women is a subject of diagnostic efficiency and has an impact in elucidating the normal function of these markers. In this study midfollicular and midluteal concentrations of serum CEA, AFP, CA 19-9, CA 125, CA 15-3 and their relations with LH, FSH, prolactin, estradiol and progesterone were evaluated during ovulatory cycles in a group of 23 healthy female individuals. Samples were collected on the 7th and 21st day of the same menstrual cycle. Tumor marker and hormone concentrations were determined with chemiluminescence or electrochemiluminescence EIA methods. A significant phase-dependent difference was observed for CA 15-3, midluteal concentrations (mean ± SEM; 26.33 ± 1.56 U/ml higher than the midfollicular (mean ± SEM; 19.27 ± 1.49 U/ml concentrations (p < 0.001. But an obvious difference for other tumor markers investigated did not exist. Significant correlations of follicular and luteal CA 125 levels with body mass index of the subjects were observed (r:0.52, p < 0.05 and r:0.57, p < 0.005, respectively.

  19. Human chorionic gonadotropin and CA 15-3 producing adenocarcinoma

    International Nuclear Information System (INIS)

    Ueckaya, G.; Oezet, A.; Arpaci, A.; Koemuercue, S.

    1998-01-01

    50 years old man suffering from primary lung adenocarcinoma presented with high levels of both beta subunit human chorionic gonadotropin (βHCG) and cancer antigen 15-3 (CA 15-3) in the absence of elevated carcinoembrionic antigen (CEA), alfa fetoprotein (AFP) and carbohydrate antigen 19-9 (CA 19-9). Although βHCG or CA 15-3 high levels were reported in adenocarcinoma of lung, this is the first report of a patient with high levels of both markers. (orig.) [de

  20. Ca4As3 – a new binary calcium arsenide

    Science.gov (United States)

    Hoffmann, Andrea V.; Hlukhyy, Viktor; Fässler, Thomas F.

    2015-01-01

    The crystal structure of the binary compound tetra­calcium triarsenide, Ca4As3, was investigated by single-crystal X-ray diffraction. Ca4As3 crystallizes in the Ba4P3 structure type and is thus a homologue of isotypic Sr4As3. The unit cell contains 32 Ca2+ cations, 16 As3− isolated anions and four centrosymmetric [As2]4– dumbbells. The As atoms in each of the dumbbells are connected by a single bond, thus this calcium arsenide is a Zintl phase. PMID:26870427

  1. Ca4As3 – a new binary calcium arsenide

    Directory of Open Access Journals (Sweden)

    Andrea V. Hoffmann

    2015-12-01

    Full Text Available The crystal structure of the binary compound tetracalcium triarsenide, Ca4As3, was investigated by single-crystal X-ray diffraction. Ca4As3 crystallizes in the Ba4P3 structure type and is thus a homologue of isotypic Sr4As3. The unit cell contains 32 Ca2+ cations, 16 As3− isolated anions and four centrosymmetric [As2]4– dumbbells. The As atoms in each of the dumbbells are connected by a single bond, thus this calcium arsenide is a Zintl phase.

  2. βCaMKII plays a nonenzymatic role in hippocampal synaptic plasticity and learning by targeting αCaMKII to synapses.

    Science.gov (United States)

    Borgesius, Nils Z; van Woerden, Geeske M; Buitendijk, Gabrielle H S; Keijzer, Nanda; Jaarsma, Dick; Hoogenraad, Casper C; Elgersma, Ype

    2011-07-13

    The calcium/calmodulin-dependent kinase type II (CaMKII) holoenzyme of the forebrain predominantly consists of heteromeric complexes of the αCaMKII and βCaMKII isoforms. Yet, in contrast to αCaMKII, the role of βCaMKII in hippocampal synaptic plasticity and learning has not been investigated. Here, we compare two targeted Camk2b mouse mutants to study the role of βCaMKII in hippocampal function. Using a Camk2b(-/-) mutant, in which βCaMKII is absent, we show that both hippocampal-dependent learning and Schaffer collateral-CA1 long-term potentiation (LTP) are highly dependent upon the presence of βCaMKII. We further show that βCaMKII is required for proper targeting of αCaMKII to the synapse, indicating that βCaMKII regulates the distribution of αCaMKII between the synaptic pool and the adjacent dendritic shaft. In contrast, localization of αCaMKII, hippocampal synaptic plasticity and learning were unaffected in the Camk2b(A303R) mutant, in which the calcium/calmodulin-dependent activation of βCaMKII is prevented, while the F-actin binding and bundling property is preserved. This indicates that the calcium/calmodulin-dependent kinase activity of βCaMKII is fully dispensable for hippocampal learning, LTP, and targeting of αCaMKII, but implies a critical role for the F-actin binding and bundling properties of βCaMKII in synaptic function. Together, our data provide compelling support for a model of CaMKII function in which αCaMKII and βCaMKII act in concert, but with distinct functions, to regulate hippocampal synaptic plasticity and learning.

  3. Controls over δ44/40Ca and Sr/Ca variations in coccoliths: New perspectives from laboratory cultures and cellular models

    Science.gov (United States)

    Mejía, Luz María; Paytan, Adina; Eisenhauer, Anton; Böhm, Florian; Kolevica, Ana; Bolton, Clara; Méndez-Vicente, Ana; Abrevaya, Lorena; Isensee, Kirsten; Stoll, Heather

    2018-01-01

    Coccoliths comprise a major fraction of the global carbonate sink. Therefore, changes in coccolithophores' Ca isotopic fractionation could affect seawater Ca isotopic composition, affecting interpretations of the global Ca cycle and related changes in seawater chemistry and climate. Despite this, a quantitative interpretation of coccolith Ca isotopic fractionation and a clear understanding of the mechanisms driving it are not yet available. Here, we address this gap in knowledge by developing a simple model (CaSri-Co) to track coccolith Ca isotopic fractionation during cellular Ca uptake and allocation to calcification. We then apply it to published and new δ 44 / 40 Ca and Sr/Ca data of cultured coccolithophores of the species Emiliania huxleyi and Gephyrocapsa oceanica. We identify changes in calcification rates, Ca retention efficiency and solvation-desolvation rates as major drivers of the Ca isotopic fractionation and Sr/Ca variations observed in cultures. Higher calcification rates, higher Ca retention efficiencies and lower solvation-desolvation rates increase both coccolith Ca isotopic fractionation and Sr/Ca. Coccolith Ca isotopic fractionation is most sensitive to changes in solvation-desolvation rates. Changes in Ca retention efficiency may be a major driver of coccolith Sr/Ca variations in cultures. We suggest that substantial changes in the water structure strength caused by past changes in temperature could have induced significant changes in coccolithophores' Ca isotopic fractionation, potentially having some influence on seawater Ca isotopic composition. We also suggest a potential effect on Ca isotopic fractionation via modification of the solvation environment through cellular exudates, a hypothesis that remains to be tested.

  4. Delta(9)-tetrahydrocannabinol activates [Ca2+], increases partly sensitive to capacitative store refilling

    NARCIS (Netherlands)

    Filipeanu, CM; deZeeuw, D; Nelemans, SA

    1997-01-01

    Delta(9)-Tetrahydrocannabinol induces [Ca2+](i) increases in DDT1MF-2 smooth muscle cells. Both Ca2+ entry and release from intracellular Ca2+ stores were concentration dependently activated. The Ca2+ entry component contributed most to the increases in [Ca2+](i). Stimulation with

  5. Acid mist and soil Ca and Al alter the mineral nutrition and physiology of red spruce

    Science.gov (United States)

    P.G. Schaberg; D.H. DeHayes; G.J. Hawley; G.R. Strimbeck; J.R. Cumming; P.F. Murakami; C.H. Borer

    2000-01-01

    We examined the effects and potential interactions of acid mist and soil solution Ca and Al treatments on foliar cation concentrations, membrane-associated Ca (mCa), ion leaching, growth, carbon exchange, and cold tolerance of red spruce (Picea rubens Sarg.) saplings. Soil solution Ca additions increased foliar Ca and Zn concentrations, and increased...

  6. Control efficacy of Ca-containing foliar fertilizers on bitter pit in bagged 'Fuji' apple and effects on the Ca and N contents of apple fruits and leaves.

    Science.gov (United States)

    Yu, Xian-Mei; Wang, Jin-Zheng; Nie, Pei-Xian; Xue, Xaio-Min; Wang, Gui-Ping; An, Miao

    2018-04-20

    The preharvest application of Ca-containing foliar fertilizers can reduce bitter pit (BP) incidence in apples and improve fruit quality by increasing the Ca content and decreasing both the N content and the N/Ca ratio in fruits. In this study, we aimed to investigate the control efficacy of Ca-containing fertilizers on BP incidence and the effects on the Ca and N contents in bagged 'Fuji' apple by spraying the foliar fertilizer containing calcium chloride (CaCl 2 ), calcium nitrate [Ca(NO 3 ) 2 ] or calcium formate [Ca(HCOO) 2 ] at early stage [5 days after full bloom (DAFB) + 40 DAFB] and at late stage (80 DAFB + 125 DAFB). The BP incidences were reduced significantly with the reduce percentage of 43.2~73.0%, and the efficacy of spraying at early stage was significantly higher than that of spraying at late stage. The Ca content of bagged apple fruits was increased while the N content and N/Ca ratio were decreased after spraying Ca-containing foliar fertilizers, however, the Ca content, N content and N/Ca ratio of apple leaves were differentially influenced. The foliar fertilizer containing CaCl 2, Ca(NO 3 ) 2 or Ca(HCOO) 2 could be used at early stage to control BP in apple and improve the quality of bagged apple fruits. This article is protected by copyright. All rights reserved.

  7. Substitution site and effects on magnetism in Sr-for-Ca substituted CaBaCo4O7

    Science.gov (United States)

    Aurelio, G.; Curiale, J.; Bardelli, F.; Junqueira Prado, R.; Hennet, L.; Cuello, G.; Campo, J.; Thiaudière, D.

    2015-10-01

    Cationic substitutions in the novel magnetoelectric compound CaBaCo4O7 lead to profound changes in its magnetic and electric behaviors. In this work, we present a structural study of the isovalent substitution Sr-for-Ca in CaBaCo4O7. X-ray diffraction, as well as neutron powder diffraction experiments, are reported for a series of samples Ca1-xSrxBaCo4O7 with 0 ≤ x ≤ 0.10 . Special emphasis is given to the identification of the substitution site, as Sr has also been reported to substitute for Ba in this crystal structure. The solubility limit for Sr at the Ca site is shown to be at x ≃ 0.08 . The variation of lattice constants with Sr-doping firmly supports the Sr-for-Ca substitution. Rietveld refinements of the Sr-substituted samples are presented, and used as starting point to analyse the local structure around Sr by means of X-ray absorption spectroscopy at the Sr K-edge. Both the near-edge absorption and the extended absorption fine-structure confirm the substitution of Sr for Ca, giving definite support to the proposed nominal formula. In addition, macroscopic magnetization measurements are presented which reveal the striking effects of Sr-substitution over the magnetic landscape of this puzzling compound.

  8. Towards reconstructing ancient seawater Mg/Ca by combining porcelaneous and hyaline foraminiferal Mg/Ca-temperature calibrations

    Science.gov (United States)

    Wit, J. C.; de Nooijer, L. J.; Haig, J.; Jorissen, F. J.; Thomas, E.; Reichart, G.-J.

    2017-08-01

    The temperature of the deep ocean plays a vital role in the Earth's climate system. Paleo-reconstructions of deep-sea temperatures have traditionally been based on the oxygen isotope composition of deep-sea benthic foraminiferal calcite shells, although this parameter depends upon polar ice volume as well as temperature. More recent reconstructions use Mg/Ca in these shells, with temperature calibrations based on empirical relationships observed in present-day oceans. Incorporation of Mg (DMg) into foraminiferal calcite is, however, not solely dependent on temperature, but also on seawater Mg/Ca. Due to its long oceanic residence time, Mg concentrations remained relatively constant over time scales of a few hundred thousand years, but varied significantly over longer geological time scales. Accurate reconstruction of past temperatures using foraminiferal Mg/Ca, therefore, hinges on our understanding of Mg/Ca seawater changes on geological timescales. We explore a novel, independent approach to reconstructing past seawater Mg/Ca using the temperature-dependent offset in DMg between porcelaneous (secreting intermediate- or high-Mg calcite, abbreviated as IMC or HMC, respectively) and hyaline (producing low-Mg calcite, abbreviated as LMC) benthic foraminifera. We calibrated the Mg/Ca-temperature dependence for Pyrgo spp. (one of the few common, large-sized porcelaneous taxa present in the deep-sea since the middle Miocene), and combined this with an existing calibration of hyaline Cibicidoides spp. to mathematically solve for changes in Mg/Ca seawater through time. We show that changes in Mg/Ca seawater can be reconstructed using the offset between porcelaneous and hyaline foraminifera, but absolute values are highly dependent on the species-specific offset between Mg/Ca seawater and Mg-partition coefficients.

  9. Temperature and Ca2+-dependence of the sarcoplasmic reticulum Ca2(+)-ATPase in haddock, salmon, rainbow trout and zebra cichlid

    DEFF Research Database (Denmark)

    Godiksen, Helene; Jessen, Flemming

    2002-01-01

    in the enzyme or its membrane lipid environment is still a matter of discussion. In this study we compared the temperature dependence and Ca2+-dependence of SR Ca2+-ATPase in haddock (Melanogrammus aeglefinus), salmon (Salmo, salar), rainbow trout (Oncorhynchus mykiss) and zebra cichlid (Cichlasoma...... nigrofasciatum). The Arrhenius plot of zebra cichlid showed a break point at 20 degreesC, and the haddock Arrhenius plot was non-linear with pronounced changes in slope in the. temperature area, 6-14 degreesC. In Arrhenius plot from both salmon and rainbow trout a plateau exists with an almost constant SR Ca2...

  10. Anandamide reduces intracellular Ca2+ concentration through suppression of Na+/Ca2+ exchanger current in rat cardiac myocytes.

    Directory of Open Access Journals (Sweden)

    Qian Li

    Full Text Available Anandamide, one of the endocannabinoids, has been reported to exhibit cardioprotective properties, particularly in its ability to limit the damage produced by ischemia reperfusion injury. However, the mechanisms underlying the effect are not well known. This study is to investigate whether anandamide alter Na(+/Ca(2+ exchanger and the intracellular free Ca(2+ concentration ([Ca(2+]i.Na(+/Ca(2+ exchanger current (I(NCX was recorded and analysed by using whole-cell patch-clamp technique and [Ca(2+]i was measured by loading myocytes with the fluorescent Ca(2+ indicator Fura-2/AM.We found that I(NCX was enhanced significantly after perfusion with simulated ischemic external solution; [Ca(2+]i was also significantly increased by simulated ischemic solution. The reversal potential of I(NCX was shifted to negative potentials in simulated ischemic external solution. Anandamide (1-100 nM failed to affect I(NCX and [Ca(2+]i in normal solution. However, anandamide (1-100 nM suppressed the increase in INCX in simulated ischemic external solution concentration-dependently and normalized INCX reversal potential. Furthermore, anandamide (100 nM significantly attenuated the increase in [Ca(2+]i in simulated ischemic solution. Blocking CB1 receptors with the specific antagonist AM251 (500 nM failed to affect the effects of anandamide on I(NCX and [Ca(2+]i in simulated ischemic solution. CB2 receptor antagonist AM630 (100 nM eliminated the effects of anandamide on I(NCX and [Ca(2+]i in simulated ischemic solution, and CB2 receptor agonist JWH133 (100 nM simulated the effects of anandamide that suppressed the increase in I(NCX and [Ca(2+]i in simulated ischemic solution. In addition, pretreatment with the Gi/o-specific inhibitor pertussis toxin (PTX, 500 ng/ml eliminated the effects of anandamide and JWH133 on I(NCX in simulated ischemic solution.Collectively, these findings suggest that anandamide suppresses calcium overload through inhibition of I(NCX during

  11. Structural and compositional characterization of synthetic (Ca,Sr)-tremolite and (Ca,Sr)-diopside solid solutions

    Science.gov (United States)

    Gottschalk, M.; Najorka, J.; Andrut, M.

    Tremolite (CaxSr1-x)2Mg5[Si8O22/(OH)2] and diopside (CaxSr1-x)Mg[Si2O6] solid solutions have been synthesized hydrothermally in equilibrium with a 1 molar (Ca,Sr)Cl2 aqueous solution at 750°C and 200 MPa. The solid run products have been investigated by optical, electron scanning and high resolution transmission electron microscopy, electron microprobe, X-ray-powder diffraction and Fourier-transform infrared spectroscopy. The synthesized (Ca,Sr)-tremolites are up to 2000 µm long and 30 µm wide, the (Ca,Sr)-diopsides are up to 150 µm long and 20 µm wide. In most runs the tremolites and diopsides are well ordered and chain multiplicity faults are rare. Nearly pure Sr-tremolite (tr0.02Sr-tr0.98) and Sr-diopside (di0.01Sr-di0.99) have been synthesized. A continuous solid solution series, i.e. complete substitution of Sr2+ for Ca2+ on M4-sites exists for (Ca,Sr)-tremolite. Total substitution of Sr2+ for Ca2+ on M2-sites can be assumed for (Ca,Sr)-diopsides. For (Ca,Sr)-tremolites the lattice parameters a, b and β are linear functions of composition and increase with Sr-content whereas c is constant. For the diopside series all 4 lattice parameters are a linear function of composition; a, b, c increase and β decreases with rising Sr-content. The unit cell volume for tremolite increases 3.47% from 906.68 Å3 for tremolite to 938.21 Å3 for Sr-tremolite. For diopside the unit cell volume increases 4.87 % from 439.91 Å3 for diopside to 461.30 Å3 for Sr-diopside. The observed splitting of the OH stretching band in tremolite is caused by different configurations of the next nearest neighbors (multi mode behavior). Resolved single bands can be attributed to the following configurations on the M4-sites: SrSr, SrCa, CaCa and CaMg. The peak positions of these 4 absorption bands are a linear function of composition. They are shifted to lower wavenumbers with increasing Sr-content. No absorption band due to the SrMg configuration on the M4-site is observed. This indicates

  12. Thermal unfolding of a Ca- and Lanthanide-binding protein

    Energy Technology Data Exchange (ETDEWEB)

    Fahmy, Karim [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biophysics; Goettfert, M. [Technische Univ. Dresden (Germany); Knoeppel, J.

    2017-06-01

    The MIIA (metal ion-induced autocleavage)-domain of the protein Vic001052 from the pathogen Vibrio coralliilyticus, comprises 173 amino acids and exhibits Ca-dependent autoproteolytic activity. It shows homology to nodulation proteins which are secreted by Rhizobiacea into plant host cells where they exert Ca-dependent functions. We have studied the structural and energetic aspects of metal protein interactions of the MIIA domain which appear attractive for engineering metal-binding synthetic peptides. Using a non-cleavable MIIA domain construct, we detected very similar structural changes upon binding to Ca{sup 2+} and Eu{sup 3+}. The thermal denaturation of the Ca-bound state was studied by circular dichroism spectroscopy. The metal-bound folded state unfolds reversibly into an unstructured metal-free state similar to the metal-free state at room temperature.

  13. Neuronal migration and its disorders affecting the CA3 region

    Directory of Open Access Journals (Sweden)

    Richard eBelvindrah

    2014-03-01

    Full Text Available In this review, we focus on CA3 neuronal migration disorders in the rodent. We begin by introducing the main steps of hippocampal development, and we summarize characteristic hippocampal malformations in human. We then describe various mouse mutants showing structural hippocampal defects. Notably, genes identified in human cortical neuronal migration disorders consistently give rise to a CA3 phenotype when mutated in the mouse. We successively describe their molecular, physiological and behavioral phenotypes that together contribute to a better understanding of CA3-dependent functions. We finally discuss potential factors underlying the CA3 vulnerability revealed by these mouse mutants and that may also contribute to other human neurological and psychiatric disorders.

  14. A vaccination strategy to SEIR-CA model

    Science.gov (United States)

    Almuzakki, Muhammad Zaki; Nuraini, Nuning

    2016-04-01

    A combination between Susceptible-Exposed-Infected-Removed (SEIR) model and Cellular Automaton (CA) called SEIR-CA model has been proposed to simulate spreading diseases through populations. We make an improvement to the parameter which describe the impact of neighborhood in CA system. We also propose a vaccination strategy to the model. Three examples are given to illustrate the model. The first one shows that the previously established SEIR-CA model does not work properly in a population with randomly distributed individuals. After an improvement to the neighborhood impact parameter has been made, the model works properly in a population with randomly distributed individuals and it is shown in the second example. The last example shows the spreading mechanisms with a chosen vaccination strategy. We also show that the vaccination strategy can reduce the number of infected individuals and can suppress the spread of the diseases.

  15. Global Database of Borehole Temperatures and Climate Reconstructions - CA-0003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data collected from borehole site CA-0003. For an accurate assessment of the relative roles of natural variability and anthropogenic influence in the Earth's...

  16. Cell surface topology creates high Ca2+ signalling microdomains

    DEFF Research Database (Denmark)

    Brasen, Jens Christian; Olsen, Lars Folke; Hallett, Maurice B

    2010-01-01

    20 microM Ca2+ to be activated. In this paper, we have resolved this apparent paradox by showing that the surface topology of cells represents an important and hitherto unrecognized feature for generating microdomains of high Ca2+ in cells. We show that whereas the standard modeling assumption...... of a smooth cell surface predicts only moderate localized effects, the more realistic "wrinkled" surface topology predicts that Ca2+ concentrations up to 80 microM can persist within the folds of membranes for significant times. This intra-wrinkle location may account for 5% of the total cell volume. Using......-wrinkle location is also a strategic location at which Ca2+ acts as a regulator of the cortical cytoskeleton and plasma membrane expansion....

  17. Mixing Corrosion of CaCO3 in Natural Waters

    Directory of Open Access Journals (Sweden)

    Qian Hui

    2011-01-01

    Full Text Available The methods of aqueous speciation calculation, pH calculation and the solubility (precipitability calculation of CaCO3 were used to study the mixing corrosion of CaCO3 in natural waters. Mixing processes were done between two unsaturated (with CaCO3 solutions, two oversaturated solutions and between an unsaturated solution and an oversaturated solution, respectively. Results show that the mixing corrosion can be divided into two different levels: mixing corrosion in strict sense and mixing corrosion in broad sense. When mixing corrosion occurs, the HCO3- concentration in one end member solution is usually higher than that in the other solution, and the Ca2+ concentration in the former solution is also usually higher than that in the latter one.

  18. Targeting Cardiomyocyte Ca2+ Homeostasis in Heart Failure

    Science.gov (United States)

    Røe, Åsmund T.; Frisk, Michael; Louch, William E.

    2015-01-01

    Improved treatments for heart failure patients will require the development of novel therapeutic strategies that target basal disease mechanisms. Disrupted cardiomyocyte Ca2+ homeostasis is recognized as a major contributor to the heart failure phenotype, as it plays a key role in systolic and diastolic dysfunction, arrhythmogenesis, and hypertrophy and apoptosis signaling. In this review, we outline existing knowledge of the involvement of Ca2+ homeostasis in these deficits, and identify four promising targets for therapeutic intervention: the sarcoplasmic reticulum Ca2+ ATPase, the Na+-Ca2+ exchanger, the ryanodine receptor, and t-tubule structure. We discuss experimental data indicating the applicability of these targets that has led to recent and ongoing clinical trials, and suggest future therapeutic approaches. PMID:25483944

  19. BCL-2, Ca, and Apoptosis in Breast Cancer

    National Research Council Canada - National Science Library

    Machen, Terry

    1998-01-01

    The central hypothesis of this project is that bcl-2 controls PCD and oncogenesis by altering Ca permeability by the ER/nuclear membranes, mitochondria and/or plasma membrane of mammary epithelial cells...

  20. Deciphering the molecular nature of ovarian cancer biomarker CA125.

    Science.gov (United States)

    Weiland, Florian; Martin, Karina; Oehler, Martin K; Hoffmann, Peter

    2012-01-01

    The ovarian cancer biomarker CA125 has been extensively investigated over the last 30 years. The knowledge about the exact molecular nature of this protein, however, remains fragmented. This review provides an overview of the structural research regarding CA125, and presents an orthogonal verification method to confirm the identity of this molecule. The need for independent identification of CA125 is exemplified by several reports where mutually exclusive data concerning the existence of isoforms and the glycan moieties is presented. Mass spectrometry can overcome the pitfalls of a single detection/identification method such as antibody probing. Independent verification of CA125 identity in characterization studies will help establish a refined model of its molecular structure that will promote the development of new approaches for diagnosis, prognosis and therapy of ovarian cancer.

  1. Deciphering the Molecular Nature of Ovarian Cancer Biomarker CA125

    Directory of Open Access Journals (Sweden)

    Peter Hoffmann

    2012-08-01

    Full Text Available The ovarian cancer biomarker CA125 has been extensively investigated over the last 30 years. The knowledge about the exact molecular nature of this protein, however, remains fragmented. This review provides an overview of the structural research regarding CA125, and presents an orthogonal verification method to confirm the identity of this molecule. The need for independent identification of CA125 is exemplified by several reports where mutually exclusive data concerning the existence of isoforms and the glycan moieties is presented. Mass spectrometry can overcome the pitfalls of a single detection/identification method such as antibody probing. Independent verification of CA125 identity in characterization studies will help establish a refined model of its molecular structure that will promote the development of new approaches for diagnosis, prognosis and therapy of ovarian cancer.

  2. Serum level of tumor marker CA-125 in ovarian pathology

    International Nuclear Information System (INIS)

    Bagni, B.; Feggi, L.M.; Prandini, N.; Pasini, S.; Mollica, G.

    1987-01-01

    The tumor marker CA-125 is an embrional glycoprotein detectable in tissues derived from celomatic epitelium. Serum Ca-125 was determined by RIA in 66 patients with various ovarian pathologies (16 malignant at stage III-IV and 50 benign). Six patients with ovarian carcinoma were monitored during the first week after surgery and chemiotherapy for a total of 150 days of treatment. It has been observed that CA-125 serum level is consistently above the normal range (>35 U/ml) in all malignant diseases. In benign pathology, levels above the normal were found to be represented almost exclusively by ovarian endometriosis. Furthermore, the results demonstrate that chemiotherapy alone is capable of lowering CA-125 serum levels. This tumor marker may be of great advantage in diagnosis and follow-up of ovarian malignancy

  3. Soc.ca: Specific Correspondence Analysis for the Social Sciences

    DEFF Research Database (Denmark)

    2017-01-01

    Specific and class specific multiple correspondence analysis on survey-like data. Soc.ca is optimized to the needs of the social scientist and presents easily interpretable results in near publication ready quality.......Specific and class specific multiple correspondence analysis on survey-like data. Soc.ca is optimized to the needs of the social scientist and presents easily interpretable results in near publication ready quality....

  4. Secure electronic commerce communication system based on CA

    Science.gov (United States)

    Chen, Deyun; Zhang, Junfeng; Pei, Shujun

    2001-07-01

    In this paper, we introduce the situation of electronic commercial security, then we analyze the working process and security for SSL protocol. At last, we propose a secure electronic commerce communication system based on CA. The system provide secure services such as encryption, integer, peer authentication and non-repudiation for application layer communication software of browser clients' and web server. The system can implement automatic allocation and united management of key through setting up the CA in the network.

  5. Envejecimiento Neuronal y Transporte de Ca2+ Intracelular

    OpenAIRE

    Hernando Pérez, Mª Elena

    2017-01-01

    El envejecimiento promueve pérdida cognitiva y susceptibilidad a enfermedades neurodegenerativas, lo que se ha relacionado con la dishomeostasis del Ca2+ intracelular. Para investigar esta hipótesis se utiliza el cultivo a largo plazo de neuronas de hipocampo de rata, modelo de envejecimiento neuronal in vitro. Mediante imagen de fluorescencia se han estudiado cambios en transporte de Ca2+ en neuronas a lo largo del envejecimiento in vitro. Las neuronas se han identificado mediante inmunofluo...

  6. PIK3CA alterations in Middle Eastern ovarian cancers

    Directory of Open Access Journals (Sweden)

    Uddin Shahab

    2009-07-01

    Full Text Available Abstract Background PI3K/AKTsignaling pathway plays an important role in cell growth, proliferation, and tumorgenesis of various malignancies. This signaling pathway has been shown to be frequently altered in several human cancers including ovarian cancers. However the role of this oncogenic signaling pathway has not been explored in the Middle Eastern epithelial ovarian cancer (EOC. Therefore, we investigated PI3K/AKT genetic alterations such as PIK3CA amplification, PIK3CA mutation, PTEN protein loss and their relationships with various clinicopathological characteristics in 156 EOCs. Results Fluorescence in situ hybridization (FISH technique and DNA sequencing were used to analyze PIK3CA amplification and mutation respectively. Expression of PIK3CA protein expression (p110 α, PTEN, p-AKT and Ki-67 was analyzed by immunohistochemistry. PIK3CA amplification was seen in 54 of 152 (35.5% EOC cases analyzed; PIK3CA gene mutations in 6/153 EOC (3.9%; KRAS mutations in 3/154 EOC (1.9%, BRAF mutations in 3/156 EOC (1.9%, p53 mutation in 50/154 EOC (32.5%, and loss of PTEN protein expression in 33/144 EOC (22.9%. p110 α overexpression was associated with increased phosphorylation of AKT-Ser 473 and with the proliferation marker Ki-67. Conclusion Our data showed mutual exclusivity between the molecular event of PIK3CA amplification and mutations in PIK3CA, KRAS, BRAF genes, which suggests that each of these alterations may individually be sufficient to drive ovarian tumor pathogenesis independently. High prevalence of genetic alterations in PI3K/AKT pathway in a Middle Eastern ovarian carcinoma provides genetic evidence supporting the notion that dysregulated PI3K/AKT pathways play an important role in the pathogenesis of ovarian cancers.

  7. Investigation of the RbCa molecule: Experiment and theory

    OpenAIRE

    Pototschnig, Johann V.; Krois, G?nter; Lackner, Florian; Ernst, Wolfgang E.

    2015-01-01

    We present a thorough theoretical and experimental study of the electronic structure of RbCa. The mixed alkali?alkaline earth molecule RbCa was formed on superfluid helium nanodroplets. Excited states of the molecule in the range of 13?000?23?000?cm?1 were recorded by resonance enhanced multi-photon ionization time-of-flight spectroscopy. The experiment is accompanied by high level ab initio calculations of ground and excited state properties, utilizing a multireference configuration interact...

  8. Negative chemical pressure effects induced by Y substitution for Ca ...

    Indian Academy of Sciences (India)

    The magnetic behavior of a solid solution, Ca3-YCo2O6, based on the `exotic' spin-chain compound, Ca3Co2O6, crystallizing in K4CdCl6-derived rhombohedral structure is investigated. Among the compositions investigated ( = 0.0, 0.3, 0.5, 0.75 and 1.0), single-phase formation persists up to = 0.75, with the ...

  9. Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

    Science.gov (United States)

    Koho, Karoliina A.; de Nooijer, Lennart J.; Fontanier, Christophe; Toyofuku, Takashi; Oguri, Kazumasa; Kitazato, Hiroshi; Reichart, Gert-Jan

    2017-06-01

    The Mn / Ca of calcium carbonate tests of living (rose-Bengal-stained) benthic foraminifera (Elphidium batialis, Uvigerina spp., Bolivina spissa, Nonionellina labradorica and Chilostomellina fimbriata) were determined in relation to pore water manganese (Mn) concentrations for the first time along a bottom water oxygen gradient across the continental slope along the NE Japan margin (western Pacific). The local bottom water oxygen (BWO) gradient differs from previous field study sites focusing on foraminiferal Mn / Ca and redox chemistry, therefore allowing further resolution of previously observed trends. The Mn / Ca ratios were analysed using laser ablation inductively coupled plasma-mass spectrometer (ICP-MS), allowing single-chamber determination of Mn / Ca. The incorporation of Mn into the carbonate tests reflects environmental conditions and is not influenced by ontogeny. The inter-species variability in Mn / Ca reflected foraminiferal in-sediment habitat preferences and associated pore water chemistry but also showed large interspecific differences in Mn partitioning. At each station, Mn / Ca ratios were always lower in the shallow infaunal E. batialis, occupying relatively oxygenated sediments, compared to intermediate infaunal species, Uvigerina spp. and B. spissa, which were typically found at greater depth, under more reducing conditions. The highest Mn / Ca was always recorded by the deep infaunal species N. labradorica and C. fimbriata. Our results suggest that although partitioning differs, Mn / Ca ratios in the intermediate infaunal taxa are promising tools for palaeoceanographic reconstructions as their microhabitat exposes them to higher variability in pore water Mn, thereby making them relatively sensitive recorders of redox conditions and/or bottom water oxygenation.

  10. Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

    Directory of Open Access Journals (Sweden)

    K. A. Koho

    2017-06-01

    Full Text Available The Mn / Ca of calcium carbonate tests of living (rose-Bengal-stained benthic foraminifera (Elphidium batialis, Uvigerina spp., Bolivina spissa, Nonionellina labradorica and Chilostomellina fimbriata were determined in relation to pore water manganese (Mn concentrations for the first time along a bottom water oxygen gradient across the continental slope along the NE Japan margin (western Pacific. The local bottom water oxygen (BWO gradient differs from previous field study sites focusing on foraminiferal Mn / Ca and redox chemistry, therefore allowing further resolution of previously observed trends. The Mn / Ca ratios were analysed using laser ablation inductively coupled plasma-mass spectrometer (ICP-MS, allowing single-chamber determination of Mn / Ca. The incorporation of Mn into the carbonate tests reflects environmental conditions and is not influenced by ontogeny. The inter-species variability in Mn / Ca reflected foraminiferal in-sediment habitat preferences and associated pore water chemistry but also showed large interspecific differences in Mn partitioning. At each station, Mn / Ca ratios were always lower in the shallow infaunal E. batialis, occupying relatively oxygenated sediments, compared to intermediate infaunal species, Uvigerina spp. and B. spissa, which were typically found at greater depth, under more reducing conditions. The highest Mn / Ca was always recorded by the deep infaunal species N. labradorica and C. fimbriata. Our results suggest that although partitioning differs, Mn / Ca ratios in the intermediate infaunal taxa are promising tools for palaeoceanographic reconstructions as their microhabitat exposes them to higher variability in pore water Mn, thereby making them relatively sensitive recorders of redox conditions and/or bottom water oxygenation.

  11. Influence of pairing in double beta decay of 48Ca

    Indian Academy of Sciences (India)

    is the natural calculation scheme for this nucleus without truncation. Recently proposed GXPF1A two-body effective interaction has been successfully tested for the fp shell [31–33] to perform 2νββ decay calculations for 48Ca. Recently, Horoi. [30] gave the 2νββ decay matrix elements and half-lives of 48Ca using full fp shell.

  12. Atrial natriuretic peptide regulates Ca channel in early developmental cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Lin Miao

    Full Text Available BACKGROUND: Cardiomyocytes derived from murine embryonic stem (ES cells possess various membrane currents and signaling cascades link to that of embryonic hearts. The role of atrial natriuretic peptide (ANP in regulation of membrane potentials and Ca(2+ currents has not been investigated in developmental cardiomyocytes. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the role of ANP in regulating L-type Ca(2+ channel current (I(CaL in different developmental stages of cardiomyocytes derived from ES cells. ANP decreased the frequency of action potentials (APs in early developmental stage (EDS cardiomyocytes, embryonic bodies (EB as well as whole embryo hearts. ANP exerted an inhibitory effect on basal I(CaL in about 70% EDS cardiomyocytes tested but only in about 30% late developmental stage (LDS cells. However, after stimulation of I(CaL by isoproterenol (ISO in LDS cells, ANP inhibited the response in about 70% cells. The depression of I(CaL induced by ANP was not affected by either Nomega, Nitro-L-Arginine methyl ester (L-NAME, a nitric oxide synthetase (NOS inhibitor, or KT5823, a cGMP-dependent protein kinase (PKG selective inhibitor, in either EDS and LDS cells; whereas depression of I(CaL by ANP was entirely abolished by erythro-9-(2-Hydroxy-3-nonyl adenine (EHNA, a selective inhibitor of type 2 phosphodiesterase(PDE2 in most cells tested. CONCLUSION/SIGNIFICANCES: Taken together, these results indicate that ANP induced depression of action potentials and I(CaL is due to activation of particulate guanylyl cyclase (GC, cGMP production and cGMP-activation of PDE2 mediated depression of adenosine 3', 5'-cyclic monophophate (cAMP-cAMP-dependent protein kinase (PKA in early cardiomyogenesis.

  13. Dynamic polarizabilities for the low lying states of Ca+

    International Nuclear Information System (INIS)

    Tang, Yong-Bo; Shi, Ting-Yun; Qiao, Hao-Xue; Mitroy, J

    2014-01-01

    The dynamic polarizabilities of the 4s, 3d and 4p states of Ca + are calculated using a relativistic structure model. The wavelengths at which the Stark shifts between different pairs of transitions are zero are calculated. Experimental determination of the magic wavelengths could prove useful in developing better atomic structure models and in particular lead to improved values of the polarizabilities for the Ca + (3d) states

  14. Negative chemical pressure effects induced by Y substitution for Ca ...

    Indian Academy of Sciences (India)

    the magnetic chain may be useful to the overall understanding of the novel magnetism of the parent compound. Keywords. Spin-chains; Ca3Co2O6; chemical pressure; magnetic order; quantum tun- neling. PACS Nos 75.50.-y; 75.30.Cr; 75.40.Cx. 1. Introduction. Among spin-chain systems, the compound, Ca3Co2O6 [1,2], ...

  15. Hippocampal CA1 pyramidal cells form functionally distinct sublayers

    OpenAIRE

    Mizuseki, Kenji; Diba, Kamran; Pastalkova, Eva; Buzsáki, György

    2011-01-01

    Summary Hippocampal CA1 pyramidal neurons have frequently been regarded as a homogeneous cell population in biophysical, pharmacological and modeling studies. Here we report robust differences between pyramidal neurons residing in the deep and superficial CA1 sublayers in the rat. Compared to their superficial peers, deep pyramidal cells fired at higher rates, burst more frequently, were more likely to have place fields and were more strongly modulated by slow oscillations of sleep. Both deep...

  16. Negative chemical pressure effects induced by Y substitution for Ca ...

    Indian Academy of Sciences (India)

    Negative chemical pressure effects on Ca3Co2O6. Figure 3. Inverse of magnetic susceptibility (χ) as a function of tempera- ture (30–300 K) for Ca3−xYxCo2O6, obtained in a field of 5 kOe. A straight line is drawn through the high-temperature linear region to highlight the x-dependence of θp. The low-temperature data ...

  17. Oxidized CaMKII (Ca2+/Calmodulin-Dependent Protein Kinase II) Is Essential for Ventricular Arrhythmia in a Mouse Model of Duchenne Muscular Dystrophy.

    Science.gov (United States)

    Wang, Qiongling; Quick, Ann P; Cao, Shuyi; Reynolds, Julia; Chiang, David Y; Beavers, David; Li, Na; Wang, Guoliang; Rodney, George G; Anderson, Mark E; Wehrens, Xander H T

    2018-04-01

    Duchenne muscular dystrophy patients are prone to ventricular arrhythmias, which may be caused by abnormal calcium (Ca 2+ ) homeostasis and elevated reactive oxygen species. CaMKII (Ca 2+ /calmodulin-dependent protein kinase II) is vital for normal Ca 2+ homeostasis, but excessive CaMKII activity contributes to abnormal Ca 2+ homeostasis and arrhythmias in cardiomyocytes. Reactive oxygen species induce CaMKII to become autonomously active. We hypothesized that genetic inhibition of CaMKII oxidation (ox-CaMKII) in a mouse model of Duchenne muscular dystrophy can alleviate abnormal Ca 2+ homeostasis, thus, preventing ventricular arrhythmia. The objective of this study was to test if selective loss of ox-CaMKII affects ventricular arrhythmias in the mdx mouse model of Duchenne muscular dystrophy. 5-(6)-Chloromethyl-2,7-dichlorodihydrofluorescein diacetate staining revealed increased reactive oxygen species production in ventricular myocytes isolated from mdx mice, which coincides with elevated ventricular ox-CaMKII demonstrated by Western blotting. Genetic inhibition of ox-CaMKII by knockin replacement of the regulatory domain methionines with valines (MM-VV [CaMKII M281/282V]) prevented ventricular tachycardia in mdx mice. Confocal calcium imaging of ventricular myocytes isolated from mdx :MM-VV mice revealed normalization of intracellular Ca 2+ release events compared with cardiomyocytes from mdx mice. Abnormal action potentials assessed by optical mapping in mdx mice were also alleviated by genetic inhibition of ox-CaMKII. Knockout of the NADPH oxidase regulatory subunit p47 phox normalized elevated ox-CaMKII, repaired intracellular Ca 2+ homeostasis, and rescued inducible ventricular arrhythmias in mdx mice. Inhibition of reactive oxygen species or ox-CaMKII protects against proarrhythmic intracellular Ca 2+ handling and prevents ventricular arrhythmia in a mouse model of Duchenne muscular dystrophy. © 2018 American Heart Association, Inc.

  18. CaCDPK15 positively regulates pepper responses to Ralstonia solanacearum inoculation and forms a positive-feedback loop with CaWRKY40 to amplify defense signaling

    Science.gov (United States)

    Shen, Lei; Yang, Sheng; Yang, Tong; Liang, Jiaqi; Cheng, Wei; Wen, Jiayu; Liu, Yanyan; Li, Jiazhi; Shi, Lanping; Tang, Qian; Shi, Wei; Hu, Jiong; Liu, Cailing; Zhang, Yangwen; Mou, Shaoliang; Liu, Zhiqin; Cai, Hanyang; He, Li; Guan, Deyi; Wu, Yang; He, Shuilin

    2016-01-01

    CaWRKY40 is a positive regulator of pepper (Capsicum annum) response to Ralstonia solanacearum inoculation (RSI), but the underlying mechanism remains largely unknown. Here, we functionally characterize CaCDPK15 in the defense signaling mediated by CaWRKY40. Pathogen-responsive TGA, W, and ERE boxes were identified in the CaCDPK15 promoter (pCaCDPK15), and pCaCDPK15-driven GUS expression was significantly enhanced in response to RSI and exogenously applied salicylic acid, methyl jasmonate, abscisic acid, and ethephon. Virus-induced gene silencing (VIGS) of CaCDPK15 significantly increased the susceptibility of pepper to RSI and downregulated the immunity-associated markers CaNPR1, CaPR1, and CaDEF1. By contrast, transient CaCDPK15 overexpression significantly activated hypersensitive response associated cell death, upregulated the immunity-associated marker genes, upregulated CaWRKY40 expression, and enriched CaWRKY40 at the promoters of its targets genes. Although CaCDPK15 failed to interact with CaWRKY40, the direct binding of CaWRKY40 to pCaCDPK15 was detected by chromatin immunoprecipitation, which was significantly potentiated by RSI in pepper plants. These combined results suggest that RSI in pepper induces CaCDPK15 and indirectly activates downstream CaWRKY40, which in turn potentiates CaCDPK15 expression. This positive-feedback loop would amplify defense signaling against RSI and efficiently activate strong plant immunity. PMID:26928570

  19. The investigation of minoxidil-induced [Ca2+]irises and non-Ca2+-triggered cell death in PC3 human prostate cancer cells.

    Science.gov (United States)

    Chen, I-Shu; Chou, Chiang-Ting; Liu, Yuan-Yuarn; Yu, Chia-Cheng; Liang, Wei-Zhe; Kuo, Chun-Chi; Shieh, Pochuen; Kuo, Daih-Huang; Chen, Fu-An; Jan, Chung-Ren

    2017-02-01

    Minoxidil is clinically used to prevent hair loss. However, its effect on Ca 2+ homeostasis in prostate cancer cells is unclear. This study explored the effect of minoxidil on cytosolic-free Ca 2+ levels ([Ca 2+ ] i ) and cell viability in PC3 human prostate cancer cells. Minoxidil at concentrations between 200 and 800 μM evoked [Ca 2+ ] i rises in a concentration-dependent manner. This Ca 2+ signal was inhibited by 60% by removal of extracellular Ca 2+ . Minoxidil-induced Ca 2+ influx was confirmed by Mn 2+ -induced quench of fura-2 fluorescence. Pre-treatment with the protein kinase C (PKC) inhibitor GF109203X, PKC activator phorbol 12-myristate 13 acetate (PMA), nifedipine and SKF96365 inhibited minoxidil-induced Ca 2+ signal in Ca 2+ containing medium by 60%. Treatment with the endoplasmic reticulum Ca 2+ pump inhibitor 2,5-ditert-butylhydroquinone (BHQ) in Ca 2+ -free medium abolished minoxidil-induced [Ca 2+ ] i rises. Conversely, treatment with minoxidil abolished BHQ-induced [Ca 2+ ] i rises. Inhibition of phospholipase C (PLC) with U73122 abolished minoxidil-evoked [Ca 2+ ] i rises. Overnight treatment with minoxidil killed cells at concentrations of 200-600 μM in a concentration-dependent fashion. Chelation of cytosolic Ca 2+ with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/AM (BAPTA/AM) did not prevent minoxidil's cytotoxicity. Together, in PC3 cells, minoxidil induced [Ca 2+ ] i rises that involved Ca 2+ entry through PKC-regulated store-operated Ca 2+ channels and PLC-dependent Ca 2+ release from the endoplasmic reticulum. Minoxidil-induced cytotoxicity in a Ca 2+ -independent manner.

  20. Prognostic Value of Preoperative Serum Levels of Five Tumor Markers (Carcinoembryonic Antigen, CA19-9, Alpha-fetoprotein, CA72-4, and CA125) in Gastric Cancer.

    Science.gov (United States)

    Kim, Ji-Hyun; Jun, Kyong-Hwa; Jung, Hun; Park, In-Soo; Chin, Hyung-Min

    2014-05-01

    There is no known specific tumor marker for gastric cancer, although several tumor markers have been used. The aim of this study was to investigate the prognostic significance of preoperative carcinoembryonic antigen (CEA), CA 19-9, alpha-fetoprotein (AFP), CA 72-4, and CA 125 levels in patients with gastric cancer. Medical records of 1,253 patients who were diagnosed with gastric adenocarcinoma were retrospectively reviewed. The clinicopathologic characteristics and disease-free survival rate of the patients were compared between positive and negative CEA, CA 19-9, AFP, CA 72-4, and CA 125 groups of patients. Additionally, the prognostic significance of each tumor marker was assessed by multivariate analysis. CEA, CA19-9, and CA72-4 were more frequently positive in patients with lymphatic and venous invasion, serosal involvement, and lymph node metastasis. The 5-year overall survival and disease free survival rates were significantly associated with elevated serum levels of CEA, CA 19-9, and CA 72-4. The depth of invasion and CA 19-9 were independent prognostic factors. Patients with elevated serum levels of CA 19-9 showed a 3.35-fold higher risk of death than patients with low levels of the marker. CA 19-9 has prognostic significance in gastric cancer, and a high preoperative serum level of CA 19-9 can be useful for estimating worse prognosis and a higher recurrence of gastric cancer.

  1. Preliminary results on the use of Ca 15-3 in malignant ovarian pathology

    International Nuclear Information System (INIS)

    Romagnoli, S.; Ferdeghini, M.; Bianchi, R.; Ferdeghini, M.; Bianchi, R.; Scatena, P.; Gaducci, A.; Bartolini, T.; Facchini, V.; Fioretti, P.

    1987-01-01

    Ca 15-3 was evaluated as a tumoral marker for ovarian carcinoma and compared to Ca 125, Ca 19-9 and TPA. Fourteen women with untreated malignant epitelial ovarian neoplasm and 52 women with various gynecological pathologies (16 benign ovarian tumors, 9 endometriosis, 16 malignant uterine tumors, 8 malignant uterine tumors and 3 vulvar carcinomas) were studied. All patients were sampled once before surgery. Patients with ovarian carcinoma were also sampled monthly for 18 months during and after chemiotherapy. Serum concentrations were assayed with an immunoradiometric assay using monoclonal antibodies (Ca 15-3, Ca 125 and Ca 19-9) or with a radioimmunoassay using polyclonal antibodies (TPA). Sensitivity and specificity were 42.9% and 92.3% for Ca 15-3, 71.4% and 94.2% for Ca 125, 28.6% and 92.3% for Ca 19-9, 71.4% and 80.8% for TPA, respectively. When Ca 15-3 was evaluated in association with Ca 125 and Ca 19-9 sensitivity and specificity were 71.4% and 88.5% for Ca 15-3 + Ca 125, and 64.3% and 88.5% for Ca 15-3 + Ca 19-9 respectively. Ca 125 gave the best accuracy and specificity. Ca 15-3 was positively correlated to Ca 125 (P<0.01) but because of its lower sensitivity cannot be used alone for monitoring ovarian malignant epithelial neoplasms

  2. Correlation of CA-125 with different stages of endometriosis

    Directory of Open Access Journals (Sweden)

    Runa Laila

    2018-03-01

    Full Text Available This study was conducted to evaluate the association of serum cancer antigen (CA-125 level with the severity of pelvic endometriosis. Seventy diagnosed cases of pelvic endometriosis were included in this study. The CA-125 level was estimated in all these patients, cutoff value of the serum CA-125 level was considered 35.0 U/mL. The correlations between serum CA-125 and different stages of endometriosis were evaluated by linear regression analysis. In Stage I of endometriosis, the mean serum CA-125 level was 21.8 ± 15.1 U/mL, in Stage II 26.0 ± 17.3 U/mL, in Stage III 83.2 ± 48.9 U/mL and in Stage IV 117.0 ± 41.6 U/mL. A significant positive correlation (r=0.729; p=0.001 was found between the serum CA-125 and different stages of endometriosis.

  3. Ca isotopic geochemistry of an Antarctic aquatic system

    Science.gov (United States)

    Lyons, W. Berry; Bullen, Thomas D.; Welch, Kathleen A.

    2017-01-01

    The McMurdo Dry Valleys, Antarctica, are a polar desert ecosystem. The hydrologic system of the dry valleys is linked to climate with ephemeral streams that flow from glacial melt during the austral summer. Past climate variations have strongly influenced the closed-basin, chemically stratified lakes on the valley floor. Results of previous work point to important roles for both in-stream processes (e.g., mineral weathering, precipitation and dissolution of salts) and in-lake processes (e.g., mixing with paleo-seawater and calcite precipitation) in determining the geochemistry of these lakes. These processes have a significant influence on calcium (Ca) biogeochemistry in this aquatic ecosystem, and thus variations in Ca stable isotope compositions of the waters can aid in validating the importance of these processes. We have analyzed the Ca stable isotope compositions of streams and lakes in the McMurdo Dry Valleys. The results validate the important roles of weathering of aluminosilicate minerals and/or CaCO3 in the hyporheic zone of the streams, and mixing of lake surface water with paleo-seawater and precipitation of Ca-salts during cryo-concentration events to form the deep lake waters. The lakes in the McMurdo Dry Valleys evolved following different geochemical pathways, evidenced by their unique, nonsystematic Ca isotope signatures.

  4. Coping with Asymmetric Channel Losses in CSMA/CA

    DEFF Research Database (Denmark)

    Paramanathan, Achuthan; Roetter, Daniel Enrique Lucani; Fitzek, Frank

    2013-01-01

    Inspired by the discrepancy between past theoretical analysis and real measurements for high-load scenarios for intersession network coding, we pinpoint and analyze the source of this discrepancy in wireless networks implementing a CSMA/CA medium access scheme. Our analysis shows that CSMA/CA is ......) confirm the sensitivity of the CSMA/CA scheme in real implementations, and (ii) shows that our adaptive protocol provides a simple, yet potent mechanism to cope with asymmetric channel losses and ultimately to enhance end-to-end throughput in high-load scenarios.......Inspired by the discrepancy between past theoretical analysis and real measurements for high-load scenarios for intersession network coding, we pinpoint and analyze the source of this discrepancy in wireless networks implementing a CSMA/CA medium access scheme. Our analysis shows that CSMA....../CA is very sensitive to asymmetric channel losses caused by channel conditions. Leveraging this analysis, we present an adaptive channel priority protocol that copes with asymmetric channel losses while being compatible with CSMA/CA. We implement this protocol and perform real-life measurements that (i...

  5. Early postischemic 45Ca accumulation in rat dentate hilus

    International Nuclear Information System (INIS)

    Benveniste, H.; Diemer, N.H.

    1988-01-01

    Several studies have found postischemic regional accumulation of calcium to be time-dependent and coincident with the progression of ischemic cell change. In the most vulnerable cells in the hippocampus one would therefore expect to find a primary and specific early uptake of calcium after ischemia. Autoradiograms of 45 Ca and 3 H-inulin distribution were investigated before and 1 h after 20 min ischemia in the rat hippocampus. Two different methodological approaches were used for administration of 45 Ca: (a) administration via microdialysis probes, (b) intraventricular injection. During control conditions the 45 Ca autoradiograms showed variations in distribution volume in accordance with 3 H-inulin determination of extracellular space size. One hour after ischemia a massive accumulation of 45 Ca was found in the dentate hilus. No change in the distribution pattern of 3 H-inulin could be demonstrated 1 h after ischemia. We suggest that 45 Ca accumulation in dentate hilus 1 h after ischemia is a result of increased Ca 2+ uptake before irreversible cell damage occurs and is not due to passive influx of calcium across a leaky plasma membrane

  6. Ca-Lignosulphonate and sclerotial viability of Sclerotinia sclerotiorum

    Directory of Open Access Journals (Sweden)

    MATTEO MONTANARI

    2012-01-01

    Full Text Available Lignosulphonates, low cost by-products of the pulping process, have shown suppressive effects against some diseases caused by soil-borne pathogens. In this study, the effect of 1.5% v/v calcium lignosulphonate (Ca-Ls amendment to two commercial potting mixes (peat + coconut fibres; PC; and municipal compost + peat + pumice; MCPP on the viability of Sclerotinia sclerotiorum sclerotia was investigated. Sclerotia were buried in the Ca-Ls amended substrates for 30 days. Non-amended PC and MCPP, sterile sand and sterile PC with and without Ca-Ls were used as controls. The viability of sclerotia recovered from PC and MCPP amended with Ca-Ls was reduced by 50 and 42% respectively compared to control treatments. Ca-Ls amendment decreased sclerotial viability by enhancing the activity of the indigenous mycoparasitic fungi, Fusarium oxysporum, Mucor spp. and Trichoderma spp. The biocontrol ability of Ca-Ls against sclerotia was due to the stimulation of microbial activity and is, therefore, strictly dependent on the microbial composition of the substrate.

  7. Formation of carrageenan-CaCO{sub 3} bioactive membranes

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Lucas F.B.; Maniglia, Bianca C.; Pereira, Lourivaldo S.; Tapia-Blácido, Delia R.; Ramos, Ana P., E-mail: anapr@ffclrp.usp.br

    2016-01-01

    The high biocompatibility and resorbability of polymeric membranes have encouraged their use to manufacture medical devices. Here, we report on the preparation of membranes consisting of carrageenan, a naturally occurring sulfated polysaccharide that forms helical structures in the presence of calcium ions. We incorporated CaCO{sub 3} particles into the membranes to enhance their bioactivity and mechanical properties. Infrared spectroscopy and X-ray diffraction data confirmed CaCO{sub 3} incorporation into the polymeric matrix. We tested the bioactivity of the samples by immersing them in a solution that mimics the ionic composition and pH of the human body fluid. The hybrid membranes generated hydroxyapatite, as attested by X-ray diffraction data. Scanning electron and atomic force microscopies aided investigation of membrane topography before and after CaCO{sub 3} deposition. The wettability and surface free energy, evaluated by contact angle measures, increased in the presence of CaCO{sub 3} particles. These parameters are important for membrane implantation in the body. Moreover, membrane stiffness was up to 110% higher in the presence of the inorganic particles, as revealed by Young's modulus. - Highlights: • Hybrid kappa and iota carrageenan-CaCO{sub 3} membranes were formed. • The hybrid membrane's origin hydroxyapatite after exposure to simulated body fluid • The carrageenan's specificity to bind Ca{sup 2+} ions tailors the surface properties.

  8. Nuclear structure of 41Ca from inelastic proton scattering

    International Nuclear Information System (INIS)

    Vold, P.B.; Cline, D.; Voigt, M.J.A. de

    1977-01-01

    Angular distributions have been measured for inelastic and elastic scattering of 19 MeV protons on 40 41 Ca. A total of 89 levels were identified below 6.4 MeV in 41 Ca with an energy resolution of 12 keV. Inelastic transition strengths have been extracted using DWBA theory with a vibrational model form factor. These transition strengths correlate well with inelastic α-scattering and electromagnetic values. The quadrupole strengths are interpreted in terms of the coexistence model and imply that the excited-core admixture in the ground states of both 40 Ca and 41 Ca are approximately 5%. The octupole strengths in 41 Ca exhibits features characteristic of the weak coupling of an fsub(7/2) neutron to the lowest 3 - state in 40 Ca. The l = 5 strength exhibits a similar weak-coupling behavior. In both cases the microscopic structure appreciably reduces the transition strength for the highest spin member of the weak-coupling multiplets. (Auth.)

  9. Meiosis, egg activation, and nuclear envelope breakdown are differentially reliant on Ca2+, whereas germinal vesicle breakdown is Ca2+ independent in the mouse oocyte

    Science.gov (United States)

    Tombes, R. M.; Simerly, C.; Borisy, G. G.; Schatten, G.

    1992-01-01

    During early development, intracellular Ca2+ mobilization is not only essential for fertilization, but has also been implicated during other meiotic and mitotic events, such as germinal vesicle breakdown (GVBD) and nuclear envelope breakdown (NEBD). In this study, the roles of intracellular and extracellular Ca2+ were examined during meiotic maturation and reinitiation at parthenogenetic activation and during first mitosis in a single species using the same methodologies. Cumulus-free metaphase II mouse oocytes immediately resumed anaphase upon the induction of a large, transient Ca2+ elevation. This resumption of meiosis and associated events, such as cortical granule discharge, were not sensitive to extracellular Ca2+ removal, but were blocked by intracellular Ca2+ chelators. In contrast, meiosis I was dependent on external Ca2+; in its absence, the formation and function of the first meiotic spindle was delayed, the first polar body did not form and an interphase-like state was induced. GVBD was not dependent on external Ca2+ and showed no associated Ca2+ changes. NEBD at first mitosis in fertilized eggs, on the other hand, was frequently, but not always associated with a brief Ca2+ transient and was dependent on Ca2+ mobilization. We conclude that GVBD is Ca2+ independent, but that the dependence of NEBD on Ca2+ suggests regulation by more than one pathway. As cells develop from Ca(2+)-independent germinal vesicle oocytes to internal Ca(2+)-dependent pronuclear eggs, internal Ca2+ pools increase by approximately fourfold.

  10. Astragaloside IV Inhibits Membrane Ca[Formula: see text] Current but Enhances Sarcoplasmic Reticulum Ca[Formula: see text] Release.

    Science.gov (United States)

    Zhao, Mei-Mi; Lian, Wen-Wen; Li, Zhuo; Shao, Dong-Xue; Chen, Si-Chong; Sun, Xue-Fei; Hu, Hui-Yuan; Feng, Rui; Guo, Feng; Hao, Li-Ying

    2017-01-01

    Astragaloside IV (AS-IV) is one of the active ingredients in Astragalus membrananceus (Huangqi), a traditional Chinese medicine. The present study investigated the effects of AS-IV on Ca[Formula: see text] handling in cardiac myocytes to elucidate its possible mechanism in the treatment of cardiac disease. The results showed that AS-IV at 1 and 10[Formula: see text][Formula: see text]M reduced KCl-induced [Ca[Formula: see text

  11. Ca2+/Calmodulin-dependent Protein Kinase IIα (αCaMKII) Controls the Activity of the Dopamine Transporter

    Science.gov (United States)

    Steinkellner, Thomas; Yang, Jae-Won; Montgomery, Therese R.; Chen, Wei-Qiang; Winkler, Marie-Therese; Sucic, Sonja; Lubec, Gert; Freissmuth, Michael; Elgersma, Ype; Sitte, Harald H.; Kudlacek, Oliver

    2012-01-01

    The dopamine transporter (DAT) is a crucial regulator of dopaminergic neurotransmission, controlling the length and brevity of dopaminergic signaling. DAT is also the primary target of psychostimulant drugs such as cocaine and amphetamines. Conversely, methylphenidate and amphetamine are both used clinically in the treatment of attention-deficit hyperactivity disorder and narcolepsy. The action of amphetamines, which induce transport reversal, relies primarily on the ionic composition of the intra- and extracellular milieus. Recent findings suggest that DAT interacting proteins may also play a significant role in the modulation of reverse dopamine transport. The pharmacological inhibition of the serine/threonine kinase αCaMKII attenuates amphetamine-triggered DAT-mediated 1-methyl-4-phenylpyridinium (MPP+) efflux. More importantly, αCaMKII has also been shown to bind DAT in vitro and is therefore believed to be an important player within the DAT interactome. Herein, we show that αCaMKII co-immunoprecipitates with DAT in mouse striatal synaptosomes. Mice, which lack αCaMKII or which express a permanently self-inhibited αCaMKII (αCaMKIIT305D), exhibit significantly reduced amphetamine-triggered DAT-mediated MPP+ efflux. Additionally, we investigated mice that mimic a neurogenetic disease known as Angelman syndrome. These mice possess reduced αCaMKII activity. Angelman syndrome mice demonstrated an impaired DAT efflux function, which was comparable with that of the αCaMKII mutant mice, indicating that DAT-mediated dopaminergic signaling is affected in Angelman syndrome. PMID:22778257

  12. TRPM5 is a transient Ca2+-activated cation channel responding to rapid changes in [Ca2+]i.

    Science.gov (United States)

    Prawitt, Dirk; Monteilh-Zoller, Mahealani K; Brixel, Lili; Spangenberg, Christian; Zabel, Bernhard; Fleig, Andrea; Penner, Reinhold

    2003-12-09

    Transient receptor potential (TRP) proteins are a diverse family of proteins with structural features typical of ion channels. TRPM5, a member of the TRPM subfamily, plays an important role in taste receptors, although its activation mechanism remains controversial and its function in signal transduction is unknown. Here we characterize the functional properties of heterologously expressed human TRPM5 in HEK-293 cells. TRPM5 displays characteristics of a calcium-activated, nonselective cation channel with a unitary conductance of 25 pS. TRPM5 is a monovalent-specific, nonselective cation channel that carries Na+, K+, and Cs+ ions equally well, but not Ca2+ ions. It is directly activated by [Ca2+]i at concentrations of 0.3-1 microM, whereas higher concentrations are inhibitory, resulting in a bell-shaped dose-response curve. It activates and deactivates rapidly even during sustained elevations in [Ca2+]i, thereby inducing a transient membrane depolarization. TRPM5 does not simply mirror levels of [Ca2+]i, but instead responds to the rate of change in [Ca2+]i in that it requires rapid changes in [Ca2+]i to generate significant whole-cell currents, whereas slow elevations in [Ca2+]i to equivalent levels are ineffective. Moreover, we demonstrate that TRPM5 is not limited to taste signal transduction, because we detect the presence of TRPM5 in a variety of tissues and we identify endogenous TRPM5-like currents in a pancreatic beta cell line. TRPM5 can be activated physiologically by inositol 1,4,5-trisphosphate-producing receptor agonists, and it may therefore couple intracellular Ca2+ release to electrical activity and subsequent cellular responses.

  13. Ca2+signaling and emesis: Recent progress and new perspectives.

    Science.gov (United States)

    Zhong, Weixia; Picca, Andrew J; Lee, Albert S; Darmani, Nissar A

    2017-01-01

    Cisplatin-like chemotherapeutics cause vomiting via calcium (Ca 2+ )-dependent release of multiple neurotransmitters (dopamine, serotonin, substance P, etc.) from the gastrointestinal enterochromaffin cells and/or the brainstem. Intracellular Ca 2+ signaling is triggered by activation of diverse emetic receptors (including tachykininergic NK 1 , serotonergic 5-HT 3 , dopaminergic D 2 , cholinergic M 1 , or histaminergic H 1 ) , whose activation in vomit-competent species can evoke emesis. Other emetogens such as cisplatin, rotavirus NSP4 protein and bacterial toxins can also induce intracellular Ca 2+ elevation. Netupitant is a highly selective neurokinin NK 1 receptor (NK 1 R) antagonist and palonosetron is a selective second-generation serotonin 5-HT 3 receptor (5-HT 3 R) antagonist with a distinct pharmacological profile. An oral fixed combination of netupitant/palonosetron (NEPA; Akynzeo(®)) with >85% antiemetic efficacy is available for use in the prevention of acute and delayed chemotherapy-induced nausea and vomiting (CINV). Cannabinoid CB 1 receptor agonists possess broad-spectrum antiemetic activity since they prevent vomiting caused by a variety of emetic stimuli including the chemotherapeutic agent cisplatin, 5-HT 3 R agonists, and D 2 R agonists. Our findings demonstrate that application of the L-type Ca 2+ channel (LTCC) agonist FPL 64176 and the intracellular Ca 2+ mobilizing agent thapsigargin (a sarco/endoplasmic reticulum Ca 2+ -ATPase inhibitor) cause vomiting in the least shrew. On the other hand, blockade of LTCCs by corresponding antagonists (nifedipine or amlodipine) not only provide broad-spectrum antiemetic efficacy against diverse agents that specifically activate emetogenic receptors such as 5-HT 3 , NK 1 , D 2 , and M 1 receptors, but can also potentiate the antiemetic efficacy of palonosetron against the non-specific emetogen, cisplatin. In this review, we will provide an overview of Ca 2+ involvement in the emetic process; discuss the

  14. Patch-clamp recording of charge movement, Ca(2+) current, and Ca(2+) transients in adult skeletal muscle fibers

    Science.gov (United States)

    Wang, ZM; Messi, ML; Delbono, O

    1999-01-01

    Intramembrane charge movement (Q), Ca(2+) conductance (G(m)) through the dihydropyridine-sensitive L-type Ca(2+) channel (DHPR) and intracellular Ca(2+) fluorescence (F) have been recorded simultaneously in flexor digitorum brevis muscle fibers of adult mice, using the whole-cell configuration of the patch-clamp technique. The voltage distribution of Q was fitted to a Boltzmann equation; the Q(max), V(1/2Q), and effective valence (z(Q)) values were 41 +/- 3.1 nC/&mgr;F, -17.6 +/- 0.7 mV, and 2.0 +/- 0.12, respectively. V(1/2G) and z(G) values were -0.3 +/- 0.06 mV and 5.6 +/- 0.34, respectively. Peak Ca(2+) transients did not change significantly after 30 min of recording. F was fit to a Boltzmann equation, and the values for V(F1/2) and z(F) were 6.2 +/- 0.04 mV and 2.4, respectively. F was adequately fit to the fourth power of Q. These results demonstrate that the patch-clamp technique is appropriate for recording Q, G(m), and intracellular [Ca(2+)] simultaneously in mature skeletal muscle fibers and that the voltage distribution of the changes in intracellular Ca(2+) can be predicted by a Hodgkin-Huxley model. PMID:10545370

  15. Effects of vitamin D metabolites on cellular Ca2+ and on Ca transport in primary cultures of bone cells.

    Science.gov (United States)

    Eilam, Y; Szydel, N; Harell, A

    1980-09-01

    Both 1,25-dihydroxycholecalciferol (1,25(OH)2D3) and 24,25-dihydroxycholecalciferol (24,25(OH)2D3) exerted direct effects on Ca2+ transport and accumulation in primary cultures of bone cells. The following changes were recorded. (1) A significant decrease in the amount of intracellular exchangeable Ca2+. (2) A marked increase in the rate constants of efflux from the 'slow'-turnover intracellular Ca pool. (3) A marked increase in the 'initial rate' of Ca influx into the cells. Thus, vitamin D metabolites caused an increase in the turnover of Ca2+ in bone cells and altered the steady-stae level of intracellular exchangeable Ca2+. Whereas the changes in the rate of efflux were abolished in the presence of inhibitors of protein synthesis, the increase in the rate of influx was not sensitive to these inhibitors. It is suggested that the changes in the two fluxes were mediated by different mechanisms and that the changes in influx were due to a direct effect of vitamin D metabolites on the cellular membranes.

  16. CA 19-9 and CA 125 as potential predictors of disease recurrence in resectable lung adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Sofi Isaksson

    Full Text Available Among patients who underwent primary surgery for non-small cell lung cancer (NSCLC, recurrent disease is frequent and cannot be accurately predicted solely from TNM stage and histopathological features. The aim of this study was to examine the association of tumor markers in pre-operative serum with recurrent disease.Blood samples were collected prior to lung cancer surgery from 107 patients with stage I-III lung adenocarcinoma surgically treated at Lund University hospital, Lund, Sweden, between 2005 and 2011. The serum tumor markers Carcinoembryonic antigen (CEA, Neuron-specific enolase (NSE, Cancer antigen 125 (CA 125, Human epididymis protein 4 (HE4 and Carbohydrate antigen (CA 19-9 were analyzed retrospectively and clinical follow-up data were collected from patient charts. Forty (37% patients were diagnosed with recurrent disease.Sixty-eight (64% patients had at least one elevated tumor marker prior to surgery. In analysis of disease-free survival (DFS, CA 125 and/or CA 19-9 were significantly associated with recurrent disease adjusted to stage and adjuvant treatment (hazard ratio 2.8, 95% confidence interval 1.4-5.7, p = 0.006.High pre-operative serum CA 19-9 and/or CA 125 might indicate an increased incidence of recurrent disease in resectable lung adenocarcinomas.

  17. Astragalus Granule Prevents Ca2+ Current Remodeling in Heart Failure by the Downregulation of CaMKII

    Directory of Open Access Journals (Sweden)

    Sinai Li

    2017-01-01

    Full Text Available Background. Astragalus was broadly used for treating heart failure (HF and arrhythmias in East Asia for thousands of years. Astragalus granule (AG, extracted from Astragalus, shows beneficial effect on the treatment of HF in clinical research. We hypothesized that administration of AG prevents the remodeling of L-type Ca2+ current (ICa-L in HF mice by the downregulation of Ca2+/calmodulin-dependent protein kinase II (CaMKII. Methods. HF mice were induced by thoracic aortic constriction (TAC. After 4 weeks of AG treatment, cardiac function and QT interval were evaluated. Single cardiac ventricular myocyte was then isolated and whole-cell patch clamp was used to record action potential (AP and ICa-L. The expressions of L-type calcium channel alpha 1C subunit (Cav1.2, CaMKII, and phosphorylated protein kinase A (p-PKA were examined by western blot. Results. The failing heart manifested distinct electrical remodeling including prolonged repolarization time and altered ICa-L kinetics. AG treatment attenuated this electrical remodeling, supported by AG-related shortened repolarization time, decreased peak ICa-L, accelerated ICa-L inactivation, and positive frequency-dependent ICa-L facilitation. In addition, AG treatment suppressed the overexpression of CaMKII, but not p-PKA, in the failing heart. Conclusion. AG treatment protected the failing heart against electrical remodeling and ICa-L remodeling by downregulating CaMKII.

  18. CA 19-9 and CA 125 as potential predictors of disease recurrence in resectable lung adenocarcinoma.

    Science.gov (United States)

    Isaksson, Sofi; Jönsson, Per; Monsef, Nastaran; Brunnström, Hans; Bendahl, Pär-Ola; Jönsson, Mats; Staaf, Johan; Planck, Maria

    2017-01-01

    Among patients who underwent primary surgery for non-small cell lung cancer (NSCLC), recurrent disease is frequent and cannot be accurately predicted solely from TNM stage and histopathological features. The aim of this study was to examine the association of tumor markers in pre-operative serum with recurrent disease. Blood samples were collected prior to lung cancer surgery from 107 patients with stage I-III lung adenocarcinoma surgically treated at Lund University hospital, Lund, Sweden, between 2005 and 2011. The serum tumor markers Carcinoembryonic antigen (CEA), Neuron-specific enolase (NSE), Cancer antigen 125 (CA 125), Human epididymis protein 4 (HE4) and Carbohydrate antigen (CA 19-9) were analyzed retrospectively and clinical follow-up data were collected from patient charts. Forty (37%) patients were diagnosed with recurrent disease. Sixty-eight (64%) patients had at least one elevated tumor marker prior to surgery. In analysis of disease-free survival (DFS), CA 125 and/or CA 19-9 were significantly associated with recurrent disease adjusted to stage and adjuvant treatment (hazard ratio 2.8, 95% confidence interval 1.4-5.7, p = 0.006). High pre-operative serum CA 19-9 and/or CA 125 might indicate an increased incidence of recurrent disease in resectable lung adenocarcinomas.

  19. Tumor marker CA-125 in adnexal inflammatory tumors

    Directory of Open Access Journals (Sweden)

    Nikolić Branka

    2006-01-01

    Full Text Available Background/Aim. The glycoprotein of a high molecular weight CA-125, which is not a specific tumor marker of ovarian cancer, is secreted by the endothelial cells of most pelvic organs. Endometriosis, inflammatory processes in the pelvic cavity, as well as some nongynecoligical malignant diseases, could be followed by the increased values of CA-125. Serial assessment of the values of CA- 125 makes it possible to avoid surgical treatment, and, by means of the used conservative treatment, to avoid malignant diseases not to be noticed. Methods. The study included 57 female patients hospitalized due to inflammable adnexal tumors. Besides following the values of serum CA-125 during and after the therapy, also performed were the transvaginal Doppler ultrasonography and the determination of the values of resistance index (RI. Results. In 27 patients (55.1% the CA-125 values ranged from 38.8 U/ml to 794 U/ml, while in 30 of the patients they were within the range of normal. In this group of the patients, besides the increased values of CA- 125, also increased were the values of leucocytes (119/l − 209/l, as well as the sedimentation rates (65−120 within the first hour. In all the 57 patients, transvaginal Doppler ultrasonography revealed the presence of adnexal tumor of inflammatory kind. The measured values of RI were within the range of 0.539−0.681. Eight of the patients were treated by the conservative - triple antibiotic therapy, while in 49 patients explorative laparotomy was performed. Hystorectomy was done in 12 of the patients, and one-side adnexectomy in 37 of them. Conclusion. The method for the assessment of CA-125 is simple and available which facilitates the monitoring of surgical, conservative or the combined therapy that is particularly significant in younger patients with inflammable adnexal tumor developed on the basis of endometrosis.

  20. In-situ thermal analysis and macroscopical characterization of Mg-xCa and Mg-0.5Ca-xZn alloy systems

    Energy Technology Data Exchange (ETDEWEB)

    Farahany, Saeed [Department of Materials Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Bakhsheshi-Rad, Hamid Reza, E-mail: Rezabakhsheshi@gmail.com [Department of Materials Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Idris, Mohd Hasbullah [Department of Materials Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Abdul Kadir, Mohammed Rafiq [Medical Implants Technology Group, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Department of Biomechanics and Biomedical Materials, Faculty of Biomedical Engineering and Health Sciences, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Lotfabadi, Amir Fereidouni [Department of Manufacturing and Industrial Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Ourdjini, Ali [Department of Materials Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2012-01-10

    Highlights: Black-Right-Pointing-Pointer The effect of Ca and Zn addition on Mg-Ca and Mg-Ca-Zn were investigated. Black-Right-Pointing-Pointer Ca and Zn addition decreased solid fraction at coherency point. Black-Right-Pointing-Pointer T{sub N}-T{sub DCP} increased by adding Ca and Zn in Mg-Ca and Mg-Ca-Zn, respectively. Black-Right-Pointing-Pointer Three reactions were detected when Zn/Ca atomic ratio less than 1.25 in Mg-Ca-Zn. Black-Right-Pointing-Pointer A new peak Mg{sub 51}Zn{sub 20} was identified in Mg-0.5Ca-9Zn in addition of other peaks. - Abstract: This research described the identification phases by thermal analysis and microscopy inspection of Mg-xCa and Mg-0.5%Ca-xZn alloys that were solidified at slow cooling rate. Analysis of cooling curve after Ca addition shows the evolution of the Mg{sub 2}Ca intermetallic phase at around 520 Degree-Sign C in addition to {alpha}-Mg phase. First derivative curves of alloys after the addition of Zn to Mg-0.5Ca alloy reveals three peaks related to {alpha}-Mg, Mg{sub 2}Ca and Ca{sub 2}Mg{sub 6}Zn{sub 3} for alloys that have Zn/Ca atomic ratio less than 1.23. The peak of Mg{sub 2}Ca reaction on the first derivative curves disappeared for alloys containing Zn/Ca ratio more than 1.23. A new peak was also observed at 330 Degree-Sign C for Mg-0.5Ca-9Zn which was identified as Mg{sub 51}Zn{sub 20}. Solid fraction at coherency point decreased with increasing Ca and Zn elements. However, coherency time and difference between the nucleation and coherency temperatures (T{sub N}-T{sub DCP}) increased by adding Ca and Zn in Mg-Ca and Mg-Ca-Zn systems.

  1. Study on the diagnostic value of combined determination of serum CA125, CA199 and SIL-2R levels in patients with endometriosis

    International Nuclear Information System (INIS)

    Yang Jingxiu; Shi Shaohong; Wang Yuping; Xie Xueqin; Qin Jibao

    2005-01-01

    Objective: To investigate the diagnostic values of combined determination of serum CA125, CA199 and SIL-2R levels in patients with endometriosis. Methods: Serum CA125, CA199 were measured with RIA and SIL-2R levels with ELISA in 54 patients with endometriosis and 35 controls. Results: The serum levels of CA125, CA199 and SIL-2R in patients with endometriosis were significantly higher than those in controls (P<0.01). The sensitivity and speciality of CA125 for endometriosis was 70.2% and 80.4% respectively, the sensitivity and speciality of CA199 for endometriosis was 62.4% and 71.8% respectively, the sensitivity and speciality of SIL-2R was 89.5% and 60.2% respectively. The sensitivity of the combined determination of CA125, CA199 and SIL-2R for endometriosis was 86.8% being significantly higher than that of CA125 and CA199 respectively. Conclusion: Combined determination of the serum CA125, CA199 and SIL-2R levels in serum can increase the diagnostic sensitivity for endometriosis. (authors)

  2. Short communication: genetic ablation of L-type Ca2+ channels abolishes depolarization-induced Ca2+ release in arterial smooth muscle.

    Science.gov (United States)

    Fernández-Tenorio, Miguel; González-Rodríguez, Patricia; Porras, Cristina; Castellano, Antonio; Moosmang, Sven; Hofmann, Franz; Ureña, Juan; López-Barneo, José

    2010-04-16

    In arterial myocytes, membrane depolarization-induced Ca(2+) release (DICR) from the sarcoplasmic reticulum (SR) occurs through a metabotropic pathway that leads to inositol trisphosphate synthesis independently of extracellular Ca(2+) influx. Despite the fundamental functional relevance of DICR, its molecular bases are not well known. Biophysical and pharmacological data have suggested that L-type Ca(2+) channels could be the sensors coupling membrane depolarization to SR Ca(2+) release. This hypothesis was tested using smooth muscle-selective conditional Ca(v)1.2 knockout mice. In aortic myocytes, the decrease of Ca(2+) channel density was paralleled by the disappearance of SR Ca(2+) release induced by either depolarization or Ca(2+) channel agonists. Ca(v)1.2 channel deficiency resulted in almost abolition of arterial ring contraction evoked by DICR. Ca(2+) channel-null cells showed unaltered caffeine-induced Ca(2+) release and contraction. These data suggest that Ca(v)1.2 channels are indeed voltage sensors coupled to the metabolic cascade, leading to SR Ca(2+) release. These findings support a novel, ion-independent, functional role of L-type Ca(2+) channels linked to intracellular signaling pathways in vascular myocytes.

  3. Skeletal muscle Ca(2+)-independent kinase activity increases during either hypertrophy or running

    Science.gov (United States)

    Fluck, M.; Waxham, M. N.; Hamilton, M. T.; Booth, F. W.

    2000-01-01

    Spikes in free Ca(2+) initiate contractions in skeletal muscle cells, but whether and how they might signal to transcription factors in skeletal muscles of living animals is unknown. Since previous studies in non-muscle cells have shown that serum response factor (SRF) protein, a transcription factor, is phosphorylated rapidly by Ca(2+)/calmodulin (CaM)-dependent protein kinase after rises in intracellular Ca(2+), we measured enzymatic activity that phosphorylates SRF (designated SRF kinase activity). Homogenates from 7-day-hypertrophied anterior latissimus dorsi muscles of roosters had more Ca(2+)-independent SRF kinase activity than their respective control muscles. However, no differences were noted in Ca(2+)/CaM-dependent SRF kinase activity between control and trained muscles. To determine whether the Ca(2+)-independent and Ca(2+)/CaM-dependent forms of Ca(2+)/CaM-dependent protein kinase II (CaMKII) might contribute to some of the SRF kinase activity, autocamtide-3, a synthetic substrate that is specific for CaMKII, was employed. While the Ca(2+)-independent form of CaMKII was increased, like the Ca(2+)-independent form of SRF kinase, no alteration in CaMKII occurred at 7 days of stretch overload. These observations suggest that some of SRF phosphorylation by skeletal muscle extracts could be due to CaMKII. To determine whether this adaptation was specific to the exercise type (i.e., hypertrophy), similar measurements were made in the white vastus lateralis muscle of rats that had completed 2 wk of voluntary running. Although Ca(2+)-independent SRF kinase was increased, no alteration occurred in Ca(2+)/CaM-dependent SRF kinase activity. Thus any role of Ca(2+)-independent SRF kinase signaling has downstream modulators specific to the exercise phenotype.

  4. Clinical Significance and Prognostic Value of CA72-4 Compared with CEA and CA19-9 in Patients with Gastric Cancer

    Directory of Open Access Journals (Sweden)

    M. Ychou

    2000-01-01

    Full Text Available Carcinoembryonic antigen (CEA and CA 19-9 are both widely used in the follow up of patients with gastrointestinal cancer. More recently another tumor marker, named CA 72-4 has been identified and characterized using two different monoclonal antibodies B72.3 and CC49. Several reports evaluated CA 72-4 as a serum tumor marker for gastric cancer and compared its clinical utility with that of CEA or CA 19-9; few reports concerned its prognostic value. In the present study, CA 72-4 is evaluated and compared with CEA and CA 19-9 in various populations of patients with gastric cancer and benign disease; for 52 patients with gastric adenocarcinoma and 57 patients without neoplastic disease CEA, CA 19-9 and CA 72-4 were evaluated before treatment. Sensitivity of the tumor markers CA 72-4, CA 19-9 and CEA at the recommended cut-off level in all 52 patients were 58%, 50% the sensitivity increased to 75%. of these markers, for non metastatic patients, multivariate analyses indicated that none of the markers were significant, when adjusted for gender and age (which were indicators of poor prognosis; patients with abnormal values of CA72-4 tended to have shorter survival than patients with normal values (p < 0.07. In the metastatic population, only high values of CA19-9 (p < 0.02 and gender (women (p < 0.03 were indicators of poor prognosis in univariate analysis; multivariate analysis revealed that both CA72-4 (p = 0.034 and CA19-9 p = 0.009, adjusted for gender were independent prognostic factors. However, CA72-4 lost significance (p = 0.41 when adjusted for CA19-9 and gender, indicating that CA19-9 provides more prognostic information than CA72-4.

  5. A model of cardiac ryanodine receptor gating predicts experimental Ca2+-dynamics and Ca2+-triggered arrhythmia in the long QT syndrome

    Science.gov (United States)

    Wilson, Dan; Ermentrout, Bard; Němec, Jan; Salama, Guy

    2017-09-01

    Abnormal Ca2+ handling is well-established as the trigger of cardiac arrhythmia in catecholaminergic polymorphic ventricular tachycardia and digoxin toxicity, but its role remains controversial in Torsade de Pointes (TdP), the arrhythmia associated with the long QT syndrome (LQTS). Recent experimental results show that early afterdepolarizations (EADs) that initiate TdP are caused by spontaneous (non-voltage-triggered) Ca2+ release from Ca2+-overloaded sarcoplasmic reticulum (SR) rather than the activation of the L-type Ca2+-channel window current. In bradycardia and long QT type 2 (LQT2), a second, non-voltage triggered cytosolic Ca2+ elevation increases gradually in amplitude, occurs before overt voltage instability, and then precedes the rise of EADs. Here, we used a modified Shannon-Puglisi-Bers model of rabbit ventricular myocytes to reproduce experimental Ca2+ dynamics in bradycardia and LQT2. Abnormal systolic Ca2+-oscillations and EADs caused by SR Ca2+-release are reproduced in a modified 0-dimensional model, where 3 gates in series control the ryanodine receptor (RyR2) conductance. Two gates control RyR2 activation and inactivation and sense cytosolic Ca2+ while a third gate senses luminal junctional SR Ca2+. The model predicts EADs in bradycardia and low extracellular [K+] and cessation of SR Ca2+-release terminate salvos of EADs. Ca2+-waves, systolic cell-synchronous Ca2+-release, and multifocal diastolic Ca2+ release seen in subcellular Ca2+-mapping experiments are observed in the 2-dimensional version of the model. These results support the role of SR Ca2+-overload, abnormal SR Ca2+-release, and the subsequent activation of the electrogenic Na+/Ca2+-exchanger as the mechanism of TdP. The model offers new insights into the genesis of cardiac arrhythmia and new therapeutic strategies.

  6. Ca2+ signalling and early embryonic patterning during zebrafish development.

    Science.gov (United States)

    Webb, Sarah E; Miller, Andrew L

    2007-09-01

    1. It has been proposed that Ca2+ signalling, in the form of pulses, waves and steady gradients, may play a crucial role in key pattern-forming events during early vertebrate development. 2. With reference to the embryo of the zebrafish (Danio rerio), herein we review the Ca2+ transients reported from the cleavage to segmentation periods. This time-window includes most of the major pattern-forming events of early development, which transform a single-cell zygote into a complex multicellular embryo with established primary germ layers and body axes. 3. Data are presented to support our proposal that intracellular Ca2+ waves are an essential feature of embryonic cytokinesis and that propagating intercellular Ca2+ waves (both long and short range) may play a crucial role in: (i) the establishment of the embryonic periderm and the coordination of cell movements during epiboly, convergence and extension; (ii) the establishment of the basic embryonic axes and germ layers; and (iii) definition of the morphological boundaries of specific tissue domains and embryonic structures, including future organ anlagen. 4. The potential downstream targets of these Ca2+ transients are also discussed, as well as how they may integrate with other pattern-forming signalling pathways known to modulate early developmental events.

  7. Human chorionic gonadotropin and CA 15-3 producing adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Ueckaya, G. [Guelhane Military Medical Academia, Ankara (Turkey). Dept. of Internal Diseases; Oezet, A.; Arpaci, A.; Koemuercue, S. [Guelhane Military Medical Academia, Ankara (Turkey). Dept. of Medical Oncology

    1998-12-31

    50 years old man suffering from primary lung adenocarcinoma presented with high levels of both beta subunit human chorionic gonadotropin ({beta}HCG) and cancer antigen 15-3 (CA 15-3) in the absence of elevated carcinoembrionic antigen (CEA), alfa fetoprotein (AFP) and carbohydrate antigen 19-9 (CA 19-9). Although {beta}HCG or CA 15-3 high levels were reported in adenocarcinoma of lung, this is the first report of a patient with high levels of both markers. (orig.) [Deutsch] Im Blut eines 50jaehrigen Mannes, der an einem primaeren Adenokarzinom der Lunge litt, wurden hohe Werte fuer die Spiegel der beiden Subunit-Formen von Human Chorionic Gonadotropin ({beta}HCG) und Krebsantigen 15-3 gefunden, waehrend die Spiegel von CEA, AFP und CA 19-9 normal waren. Obwohl hohe Anteile an {beta}HCG und an Ca 15-3 vorher bekannt waren, handelt es sich um den ersten Bericht mit hohen Blutspiegeln fuer beide Krebsmarker. (orig.)

  8. The CaO orange system in meteor spectra

    Science.gov (United States)

    Berezhnoy, A. A.; Borovička, J.; Santos, J.; Rivas-Silva, J. F.; Sandoval, L.; Stolyarov, A. V.; Palma, A.

    2018-02-01

    The CaO orange band system was simulated in the region 5900-6300 Å and compared with the experimentally observed spectra of Benešov bolide wake. The required vibronic Einstein emission coefficients were estimated by means of the experimental radiative lifetimes under the simplest Franck-Condon approximation. A moderate agreement was achieved, and the largest uncertainties come from modeling shape of FeO orange bands. Using a simple model the CaO column density in the wake of the Benešov bolide at the height of 29 km was estimated as (5 ± 2) × 1014 cm-2 by a comparison of the present CaO spectra with the AlO bands nicely observed at 4600-5200 Å in the same spectrum. The obtained CaO content is in a good agreement with the quenching model developed for the impact-produced cloud, although future theoretical and experimental studies of both CaO and FeO orange systems contribution would be needed to confirm these results.

  9. Identifying vital effects in Halimeda algae with Ca isotopes

    Directory of Open Access Journals (Sweden)

    C. L. Blättler

    2014-12-01

    Full Text Available Geochemical records of biogenic carbonates provide some of the most valuable records of the geological past, but are often difficult to interpret without a mechanistic understanding of growth processes. In this experimental study, Halimeda algae are used as a test organism to untangle some of the specific factors that influence their skeletal composition, in particular their Ca-isotope composition. Algae were stimulated to precipitate both calcite and aragonite by growth in artificial Cretaceous seawater, resulting in experimental samples with somewhat malformed skeletons. The Ca-isotope fractionation of the algal calcite (−0.6‰ appears to be much smaller than that for the algal aragonite (−1.4‰, similar to the behaviour observed in inorganic precipitates. However, the carbonate from Halimeda has higher Ca-isotope ratios than inorganic forms by approximately 0.25‰, likely because of Rayleigh distillation within the algal intercellular space. In identifying specific vital effects and the magnitude of their influence on Ca-isotope ratios, this study suggests that mineralogy has a first-order control on the marine Ca-isotope cycle.

  10. A role for CA3 in social recognition memory.

    Science.gov (United States)

    Chiang, Ming-Ching; Huang, Arthur J Y; Wintzer, Marie E; Ohshima, Toshio; McHugh, Thomas J

    2018-02-02

    Social recognition memory is crucial for survival across species, underlying the need to correctly identify conspecifics, mates and potential enemies. In humans the hippocampus is engaged in social and episodic memory, however the circuit mechanisms of social memory in rodent models has only recently come under scrutiny. Work in mice has established that the dorsal CA2 and ventral CA1 regions play critical roles, however a more comprehensive comparative analyses of the circuits and mechanisms required has not been reported. Here we employ conditional genetics to examine the differential contributions of the hippocampal subfields to social memory. We find that the deletion of NMDA receptor subunit 1 gene (NR1), which abolishes NMDA receptor synaptic plasticity, in CA3 pyramidal cells led to deficits in social memory; however, mice lacking the same gene in DG granule cells performed indistinguishable from controls. Further, we use conditional pharmacogenetic inhibition to demonstrate that activity in ventral, but not dorsal, CA3 is necessary for the encoding of a social memory. These findings demonstrated CA3 pyramidal cell plasticity and transmission contribute to the encoding of social stimuli and help further identify the distinct circuits underlying the role of the hippocampus in social memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Novel method of generation of Ca(HCO32 and CaCO3 aerosols and first determination of hygroscopic and cloud condensation nuclei activation properties

    Directory of Open Access Journals (Sweden)

    A. Trimborn

    2010-09-01

    Full Text Available Atmospheric mineral aerosols contain CaCO3 as a reactive component. A novel method to produce CaCO3 aerosol was developed by spraying Ca(HCO32 solution, which was generated from a CaCO3 suspension and CO2. By aerosol mass spectrometry the freshly sprayed and dried aerosol was characterized to consist of pure Ca(HCO32 which under annealing in a tube furnace transformed into CaCO3. Transmission Electron Microscopy demonstrated that the particles produced were spherical. The method was able to generate aerosol of sufficient concentration and proper size for the study of physiochemical properties and investigations of heterogeneous reactions of mineral aerosol. The dried Ca(HCO32 particles were somewhat more hygroscopic than CaCO3 particles. However, during humidification a restructuring took place and ∼2/3 of the Ca(HCO32 was transformed to CaCO3. The mixed Ca(HCO32/CaCO3(s particles were insoluble with a growth factor of 1.03 at 95% (hygroscopicity parameter κ=0.011±0.007 relative humidity. This compares to a corresponding growth factor of 1.01 for CaCO3(s (κ=0.0016±0.0004. Mass spectrometric composition analysis, restructuring, and insolubility of the mixed particles suggested that solid Ca(HCO32(s was observed. This would be in contrast to the current belief that Ca(HCO32(s is thermodynamically instable. The CCN activity of Ca(HCO32(s aerosol (κ≈0.15 is remarkably higher than that of CaCO3 aerosol (κ=0.0019±0.0007 and less than that of Ca(NO32. The noticeable but limited solubility of Ca(HCO32 of ≈0.01 mol/l explains limited hygroscopic growth and good CCN activity. Experiments in the Large Jülich Aerosol Chamber indicated that Ca(HCO32(s could exist for several hours under dry atmospheric conditions. However, it was likely buried in a protective layer of CaCO3(s. We conclude that Ca(HCO32 may be formed in the atmosphere in cloud droplets of activated mineral dust by reaction of CaCO3 with CO2 and H2O. The presence of Ca(HCO32 and

  12. Effects of Ca2+, Mg2+ and calmodulin on the formation and decomposition of the phosphorylated intermediate of the erythrocyte Ca2+-stimulated ATPase.

    OpenAIRE

    Allen, B G; Katz, S; Roufogalis, B D

    1987-01-01

    Formation of the phosphorylated intermediate (ECaP) of the human erythrocyte Ca2+-stimulated ATPase (Ca2+-ATPase) was more rapid and reached steady state sooner at 400 microM-Ca2+ than at 1 microM-Ca2+. Calmodulin increased the apparent rate of ECaP formation at 1 microM-Ca2+, whereas at 400 microM-Ca2+, calmodulin decreased the steady-state level of the ECaP without affecting its apparent rate of formation. Removal of endogenous Mg2+ with trans-1,2-diaminocyclohexane-NNN'N'-tetra-acetic acid...

  13. The Correlation between Serum and Peritoneal Fluid CA125 The Correlation between Serum and Peritoneal Fluid CA125

    Directory of Open Access Journals (Sweden)

    Saghar Salehpour

    2009-01-01

    Full Text Available Background: Despite a high prevalence of endometriosis, there still exist many challenges indiagnosing the disease. This study aims to evaluate non-invasive and practical diagnostic methodsby measuring serum and peritoneal fluid CA 125 levels in patients with endometriosis. A secondaryaim is to determine the correlation between these markers with the stage of disease as well as therelationship of the two markers with each other.Materials and Methods: This is a cross-sectional study of 60 women who underwent laparoscopyfor benign conditions. Based on laparoscopic findings and biopsy results, patients were divided to twogroups; one group included patients with pelvic endometriosis (35 patients and the second enrolledpatients free from endometriosis (25 patients. Serum and peritoneal fluid specimens were provided at thetime of laparoscopy and CA125 levels were then assessed by electrochemiluminescence immunoassay.Results: Mean serum and peritoneal fluid CA125 levels were significantly higher in women withendometriosis as compared to the control group (26.42 ± 24.34 IU/ml versus 12.64 ± 6.87 IU/mlin serum and 2203.54 + 993.19 IU/ml versus 1583.42 ± 912.51 IU/ml in peritoneal fluid, p<0.05.CA 125 levels also varied proportionally with the stage of endometriosis; but showed a significantdifference only in higher stages of the disease, both in serum and peritoneal fluid. We calculatedthe cut-off value suggesting a diagnosis of pelvic endometriosis as 14.70 IU/ml for serum and1286.5 IU/ml for peritoneal fluid CA125. A linear correlation between CA 125 levels in serum andperitoneal fluid in patients with pelvic endometriosis has also been observed.Conclusion: Serum and peritoneal fluid CA 125 levels are simple and non-surgical tools fordiagnosing and staging pelvic endometriosis. These markers are of greater diagnostic value inhigher stages of the disease.

  14. The effect of theophylline on the labelling of nitracellular myocardial calcium with 45Ca

    International Nuclear Information System (INIS)

    Sausen, F.H.

    1973-01-01

    The effect of theophylline of varying concentration on the labelling of intracellular myocardial calcium was investigated by isotope tests with radioactively labelled Ca ( 45 Ca) in isolated, electrically stimulated left auricles of guinea pigs. The preparates were incubated in a 45 Ca solution for 60 minutes, and activity uptake and intracellular Ca concentration were determined. In contrast to earlier investigations, the extracellular Ca was removed after charge by rinsing the resting auricles with inactive, Ca ++ - and Na + -free choline chloride solution. Under controlled conditions, the intercellular Ca was found to be 45 Ca-labelled by about 36% theophylline in 'therapeutical' concentration (5 x 10 -4 g/ml) induced a significant increase of the labelled Ca fraction of 16.9% as compared to the controls. 'Toxic' theophylline concentrations, too, lead to a significantly higher absorption of 45 Ca. The interchangeable intracellular Ca fraction increased by 11.7% and 10.3% as compared to the untreated preparates. The findings are discussed with regard to earlier investigations on the influence of methylxanthines on the Ca metabolism of the heart. The author assumes that the positively inotropic effect of theophylline and the theophylline-induced contracture may be ascribed to a shift in the intracellular Ca distribution towards ionized Ca. This shift could be explained by a suppression of Ca rebinding in intracellular Ca storage places or by Ca release from these structures. (orig./AK) [de

  15. Crosstalk between mitochondrial and sarcoplasmic reticulum Ca2+ cycling modulates cardiac pacemaker cell automaticity.

    Directory of Open Access Journals (Sweden)

    Yael Yaniv

    Full Text Available Mitochondria dynamically buffer cytosolic Ca(2+ in cardiac ventricular cells and this affects the Ca(2+ load of the sarcoplasmic reticulum (SR. In sinoatrial-node cells (SANC the SR generates periodic local, subsarcolemmal Ca(2+ releases (LCRs that depend upon the SR load and are involved in SANC automaticity: LCRs activate an inward Na(+-Ca(2+ exchange current to accelerate the diastolic depolarization, prompting the ensemble of surface membrane ion channels to generate the next action potential (AP.To determine if mitochondrial Ca(2+ (Ca(2+ (m, cytosolic Ca(2+ (Ca(2+ (c-SR-Ca(2+ crosstalk occurs in single rabbit SANC, and how this may relate to SANC normal automaticity.Inhibition of mitochondrial Ca(2+ influx into (Ru360 or Ca(2+ efflux from (CGP-37157 decreased [Ca(2+](m to 80 ± 8% control or increased [Ca(2+](m to 119 ± 7% control, respectively. Concurrent with inhibition of mitochondrial Ca(2+ influx or efflux, the SR Ca(2+ load, and LCR size, duration, amplitude and period (imaged via confocal linescan significantly increased or decreased, respectively. Changes in total ensemble LCR Ca(2+ signal were highly correlated with the change in the SR Ca(2+ load (r(2 = 0.97. Changes in the spontaneous AP cycle length (Ru360, 111 ± 1% control; CGP-37157, 89 ± 2% control in response to changes in [Ca(2+](m were predicted by concurrent changes in LCR period (r(2 = 0.84.A change in SANC Ca(2+ (m flux translates into a change in the AP firing rate by effecting changes in Ca(2+ (c and SR Ca(2+ loading, which affects the characteristics of spontaneous SR Ca(2+ release.

  16. Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4 : Calculated dehydrogenation enthalpy, including zero point energy, and the structure of the phonon spectra

    NARCIS (Netherlands)

    Marashdeh, A.; Frankcombe, T.J.

    2008-01-01

    The dehydrogenation enthalpies of Ca(AlH4)2, CaAlH5, and CaH2+6LiBH4 have been calculated using density functional theory calculations at the generalized gradient approximation level. Harmonic phonon zero point energy (ZPE) corrections have been included using Parlinski’s direct method. The

  17. Ca2+ signaling in pancreatic acinar cells: physiology and pathophysiology

    Directory of Open Access Journals (Sweden)

    O.H. Petersen

    2009-01-01

    Full Text Available The pancreatic acinar cell is a classical model for studies of secretion and signal transduction mechanisms. Because of the extensive endoplasmic reticulum and the large granular compartment, it has been possible - by direct measurements - to obtain considerable insights into intracellular Ca2+ handling under both normal and pathological conditions. Recent studies have also revealed important characteristics of stimulus-secretion coupling mechanisms in isolated human pancreatic acinar cells. The acinar cells are potentially dangerous because of the high intra-granular concentration of proteases, which become inappropriately activated in the human disease acute pancreatitis. This disease is due to toxic Ca2+ signals generated by excessive liberation of Ca2+ from both the endoplasmic reticulum and the secretory granules.

  18. Crystal Structure of the Vanadate-Inhibited Ca2+-ATPase

    DEFF Research Database (Denmark)

    Clausen, Johannes D.; Bublitz, Maike; Arnou, Bertrand Jean-Paul

    2016-01-01

    Vanadate is the hallmark inhibitor of the P-type ATPase family; however, structural details of its inhibitory mechanism have remained unresolved. We have determined the crystal structure of sarcoplasmic reticulum Ca2+-ATPase with bound vanadate in the absence of Ca2+. Vanadate is bound...... at the catalytic site as a planar VO3− in complex with water and Mg2+ in a dephosphorylation transition-state-like conformation. Validating bound VO3− by anomalous difference Fourier maps using long-wavelength data we also identify a hitherto undescribed Cl− site near the dephosphorylation site. Crystallization...... nucleotide analogs in the E2·VO3− structure with that in E2·BeF3− (E2P ground state analog) reveals multiple binding modes to the Ca2+-ATPase....

  19. CaPiTo: protocol stacks for services

    DEFF Research Database (Denmark)

    Gao, Han; Nielson, Flemming; Nielson, Hanne Riis

    2011-01-01

    CaPiTo allows the modelling of service-oriented applications using process algebras at three levels of abstraction. The abstract level focuses on the key functionality of the services; the plug-in level shows how to obtain security using standardised protocol stacks; finally, the concrete level...... for ensuring the absence of security flaws. The method used is based on static analysis of the corresponding LySa specifications. We illustrate the development on two industrial case studies; one taken from the banking sector and the other a single sign-on protocol....... allows to consider how security is obtained using asymmetric and symmetric cryptographic primitives. The CaPiTo approach therefore caters for a variety of developers that need to cooperate on designing and implementing service-oriented applications. We show how to formally analyse CaPiTo specifications...

  20. Spins, moments and charge radii beyond $^{48}$Ca

    CERN Multimedia

    Neyens, G; Rajabali, M M; Hammen, M; Blaum, K; Froemmgen, N E; Garcia ruiz, R F; Kreim, K D; Budincevic, I

    Laser spectroscopy of $^{49-54}$Ca is proposed as a continuation of the experimental theme initiated with IS484 “Ground-state properties of K-isotopes from laser and $\\beta$-NMR spectroscopy” and expanded in INTC-I-117 “Moments, Spins and Charge Radii Beyond $^{48}$Ca.” It is anticipated that the charge radii of these isotopes can show strong evidence for the existence of a sub-shell closure at N=32 and could provide a first tentative investigation into the existence of a shell effect at N=34. Furthermore the proposed experiments will simultaneously provide model-independent measurements of the spins, magnetic moments and quadrupole moments of $^{51,53}$Ca permitting existing and future excitation spectra to be pinned to firm unambiguous ground states.

  1. Evidence of a stable binary CdCa quasicrystalline phase

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Jensen, C.H.; Rasmussen, A.R.

    2001-01-01

    Quasicrystals with a primitive icosahedral structure and a quasilattice constant of 5.1215 Angstrom have been synthesized in a binary Cd-Ca system. The thermal stability of the quasicrystal has been investigated by in situ high-temperature x-ray powder diffraction using synchrotron radiation. It ....... It is demonstrated that the binary CdCa quasicrystal is thermodynamic stable up to its melting temperature. The linear thermal expansion coefficient of the quasicrystal is 2.765x10(-5) K-1. (C) 2001 American Institute of Physics.......Quasicrystals with a primitive icosahedral structure and a quasilattice constant of 5.1215 Angstrom have been synthesized in a binary Cd-Ca system. The thermal stability of the quasicrystal has been investigated by in situ high-temperature x-ray powder diffraction using synchrotron radiation...

  2. The immunoradiometric assay for carbohydrate antigen CA-242

    International Nuclear Information System (INIS)

    Chen Zhizhou

    1991-01-01

    Using 125 I-labelled monoclonal antibody (C242) against carbohydrate antigen CA-242, the sandwich immunoradiometric assay (IRMA) was developed. In preliminary clinical application of this method, the results of serum CA-242 measurements were 2.5 ± 4.5 U/ml for 77 normal individuals, 3.5 ± 7.0 U/ml for 128 cases of benign diseases, and 56.0 ± 91.3 U/ml for 210 cases of malignant tumors. The CA-242 values of patients with malignant tumors were significantly higher than that of patients with benign diseases. Taking 12 U/ml as normal upper limit, the positive detective rates of pancreatic and colorectal cancers were 86.6% and 62.0% respectively, while the false positive rate for normal individuals was 4%

  3. Ca{sup 2+}/calmodulin-dependent protein kinase phosphatase (CaMKP/PPM1F) interacts with neurofilament L and inhibits its filament association

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Hana [Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521 (Japan); Katoh, Tsuyoshi [Department of Biochemistry, Asahikawa Medical University, Asahikawa, 078-8510 (Japan); Nakagawa, Ryoko; Ishihara, Yasuhiro [Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521 (Japan); Sueyoshi, Noriyuki; Kameshita, Isamu [Department of Life Sciences, Faculty of Agriculture, Kagawa University, Kagawa, 761-0795 (Japan); Taniguchi, Takanobu [Department of Biochemistry, Asahikawa Medical University, Asahikawa, 078-8510 (Japan); Hirano, Tetsuo; Yamazaki, Takeshi [Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521 (Japan); Ishida, Atsuhiko, E-mail: aishida@hiroshima-u.ac.jp [Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, 739-8521 (Japan)

    2016-09-02

    Ca{sup 2+}/calmodulin-dependent protein kinase phosphatase (CaMKP/PPM1F) is a Ser/Thr phosphatase that belongs to the PPM family. Growing evidence suggests that PPM phosphatases including CaMKP act as a complex with other proteins to regulate cellular functions. In this study, using the two-dimensional far-western blotting technique with digoxigenin-labeled CaMKP as a probe, in conjunction with peptide mass fingerprinting analysis, we identified neurofilament L (NFL) as a CaMKP-binding protein in a Triton-insoluble fraction of rat brain. We confirmed binding of fluorescein-labeled CaMKP (F-CaMKP) to NFL in solution by fluorescence polarization. The analysis showed that the dissociation constant of F-CaMKP for NFL is 73 ± 17 nM (n = 3). Co-immunoprecipitation assay using a cytosolic fraction of NGF-differentiated PC12 cells showed that endogenous CaMKP and NFL form a complex in cells. Furthermore, the effect of CaMKP on self-assembly of NFL was examined. Electron microscopy revealed that CaMKP markedly prevented NFL from forming large filamentous aggregates, suggesting that CaMKP-binding to NFL inhibits its filament association. These findings may provide new insights into a novel mechanism for regulating network formation of neurofilaments during neuronal differentiation. - Highlights: • NFL was identified as a CaMKP-binding protein in an insoluble fraction of rat brain. • CaMKP bound to NFL in solution with a K{sub d} value of 73 ± 17 nM. • A CaMKP-NFL complex was found in NGF-differentiated PC12 cells. • CaMKP-binding to NFL inhibited its filament association. • CaMKP may regulate network formation of neurofilaments in neurons.

  4. Clinical value of multi-tumor markers detection with (CEA, CA19-9, CA72-4) for diagnosis of gastric malignancy

    International Nuclear Information System (INIS)

    Liu Yun; Li Jiangang

    2007-01-01

    Objective: To assess the clinical value of multi-tumor markers detection with (CEA, CA19-9, CA72-4) for diagnosis of gastric malignancy. Methods: Serum CEA, CA19-9, CA72-4 contents were measured with IRMA in 228 patients with gastric malignancies, 152 patients with benign gastric disorders and 200 controls. Results: The positive rates of single marker detection were all above 70% and that of CA72-4 was the highest (84.21%), next was CA19-9 (75.43%). Three tumor markers were all negative in only 4 cases (false negative rate was 1.75% ). So combined detection of 3 tumor markers could improve the positive rate to 98.25%. With combined determination of two markers, double positive rate for different sets of combinations was: 61.84% for CA72-4 + CA19-9, 51.31% for CA72-4 + CEA and 48.24% for CEA + CA19-9. Conclusion: It was suggested that for screening, CA72-4 was the first choice in single marker detections, and CA72-4 + CA19-9 was the first choice for combined detections of two markers. For follow-up, a combination of 2 markers with highest positive rate for the specific histopathologic type (i. e. carcinoma, leiomyosarcoma or lymphosarcoma) should be used throughout the study. (authors)

  5. Phase transformations of (Ca, Ti)-partially stabilized zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Hon Yungshon; Shen Pouyan (Inst. of Materials Science and Engineering, Nation Sun Yat-Sen Univ., Kaohsiung (Taiwan))

    1991-01-20

    The results of phase transformation and microstructural investigation of the ZrO{sub 2}-rich corner of the CaO-TiO{sub 2}-ZrO{sub 2} system are reported. Samples of Ca-PSZ powder (where PSZ is partially stabilized zirconia) containing 10.8 mol.% CaO, had added to them 0-14 mol.% TiO{sub 2} (designated specimens 0T to 14T). The samples were sintered at 1600deg C for 6 h and studied by X-ray diffraction and electron microscopy. Saturation of TiO{sub 2} in the cubic (c) zirconia was reached at a total TiO{sub 2} addition of about 4 mol.% at 1600deg C, whereas the solubility limit in tetragonal (t) zirconia was not reached in the composition range studied. The t-zirconia precipitates remained tweed in the cubic matrix for specimens 2T and 4T, but became lenticular with the (101) habit plane for specimens having a larger TiO{sub 2} content (e.g. 8T). The amount of t-zirconia increased with increasing TiO{sub 2} content at 1600deg C. The addition of TiO{sub 2} also enhanced the eutectoid decomposition of Ca-PSZ to form the PHI{sub 1}-phase (CaZr{sub 4}O{sub 9}). Calzirtite (Ca{sub 2}Zr{sub 5}Ti{sub 2}O{sub 16}) was precipitated from the shell of the zirconia grains in specimen 8T. (orig.).

  6. Geoamenazas y vulnerabilidad en Cañas, Guanacaste

    Directory of Open Access Journals (Sweden)

    Sánchez Castillo, Sergio

    2003-09-01

    Full Text Available Este artículo se explica en que consiste el Proyecto Piloto de Geoamenazas y Vulnerabilidad, el cual se desarrolla en el cantón de Cañas. Este proyecto es auspiciado y financiado por diferentes organismos internacionales y su ejecución está a cargo de la Comisión Nacional de Prevención de Riesgos y Atención de Emergencias (CNE. Se presentan los aspectos que propiciaron la escogencia del cantón de Cañas: amenaza sísmica, composición de los suelos, amenaza de inundación, base de datos catastrales en formato digital, Plan Regulador y un Comité Local de Emergencias activo. La metodología utilizada en el proyecto incluyó la aplicación de un censo en el Distrito Central de Cañas y se desarrollaron talleres con expertos internacionales y de instituciones nacionales This articles explains what the Geo Threats and Vulnerability Pilot Project is. This Project is developed in the Cañas canton. It is sponsored and financed by different international organisms and its execution is the responsibility of the National Commission of Risk Prevention and Emergency Response (Comisión Nacional de Prevención de Riesgos y Atención de Emergencias - CNE. It presents the aspects that motivated choosing the canton of Cañas: seismic threat, soil composition, flood threat, digital cadastral data, Regulatory Plan and an active Local Emergency Committee. The methodology used in the Project included a census in the main district of Cañas and the development of workshops with international and national experts

  7. Synthesis of crystalline Si-based nanosheets by extraction of Ca from CaSi2 in inositol hexakisphosphate solution

    Science.gov (United States)

    Meng, Xiang; Sasaki, Kenta; Sano, Koki; Yuan, Peiling; Tatsuoka, Hirokazu

    2017-05-01

    Crystalline Si-based nanosheets were successfully synthesized from CaSi2 by a simple soft chemical synthetic method in solution. By immersing CaSi2 powder or CaSi2/Si substrates in an inositol hexakisphosphate (IP6) solution, Ca atoms were extracted from the CaSi2 particles, then Si-based nanosheets were formed. The morphological, structural and optical properties of the Si-based nanosheets were investigated. It is noted that the thin Si-based nanosheets stacked with a void space formed bundle structures, and the nanosheets were easily exfoliated from the bundles to expose the surfaces corresponding to the Si{111} planes. Meanwhile, the surface of the Si nanosheets might be terminated by O, H, or OH bonds. The Si-based nanosheet bundles were then formed and directly rooted to the Si(111) substrates, and had a remarkably highly symmetrical morphology. This study demonstrated a simple method for preparing Si-based nanosheets, and electro- and photo-chemical applications would possibly be expected, such as in lithium ion batteries.

  8. Structural studies of Ca2+-ATPase ligand and regulatory complexes

    DEFF Research Database (Denmark)

    Drachmann, Nikolaj Düring

    2015-01-01

    to explore the possibilities for an efficient screening of ligand-bound SERCA structures, serial femtosecond crystallography experiments of microcrystals of SERCA1a in the Ca2+ bound state and in a vanadate stabilised E2 state was conducted. A structure obtained at 2.8 Å maximum resolution of the proof......-of-concept Ca2+ bound crystal form, indicated that the information content of SFX data is higher than synchrotron data, and ligands and ions can be detected with low redundant data. The data of the E2 stabilised form was processed to 5 Å resolution, and it was possible to extract useful anomalous data showing...

  9. Structural and magnetic properties of the layered compound Ca2 ...

    Indian Academy of Sciences (India)

    Experimental. Polycrystalline sample of Ca2.375La0.125Sr0.5GaMn2O8 was synthesized by the con- ventional solid state reaction method. The stoichiometric amount of high purity. (>99.9%) CaCO3, SrCO3, La2O3, Ga2O3 and MnO2 were initially mixed and de- carbonated at 1000◦C for 24 h and then pressed into a pellet ...

  10. Pb2+ Modulates Ca2+ Membrane Permeability In Paramecium

    Science.gov (United States)

    Bernal-Martínez, Juan; Ortega Soto, Arturo

    2004-09-01

    Intracellular recording experiments in current clamp configuration were done to evaluate whether Pb2+ modulates ionic membrane permeability in the fresh water Paramecium tetraurelia. It was found that Pb2+ triggers in a dose-dependent manner, a burst of spontaneous action potentials followed by a robust and sustained after hyper-polarization. In addition, Pb2+ increased the frequency of firing the spontaneous Ca2+-Action Potential and also, the duration of Ca2+-Action Potential, in a dose and reversibly-dependent manner. These results suggest that Pb2+ increases calcium membrane permeability of Paramecium and probably activates a calcium-dependent-potassium conductance in the ciliate.

  11. The Cancer Biomedical Informatics Grid (caBIG) Security Infrastructure.

    Science.gov (United States)

    Langella, Stephen; Oster, Scott; Hastings, Shannon; Siebenlist, Frank; Phillips, Joshua; Ervin, David; Permar, Justin; Kurc, Tahsin; Saltz, Joel

    2007-10-11

    Security is a high priority issue in medical domain, because many institutions performing biomedical research work with sensitive medical data regularly. This issue becomes more complicated, when it is desirable or needed to access and analyze data in a multi-institutional setting. In the NCI cancer Biomedical Informatics Grid (caBIG) program, several security issues were raised that existing security technologies could not address. Considering caBIG is envisioned to span a large number of cancer centers and investigator laboratories, these issues pose considerable challenge. In this paper we present these issues and the infrastructure, referred to as GAARDS, which has been developed to address them.

  12. The Cancer Biomedical Informatics Grid (caBIG™) Security Infrastructure

    Science.gov (United States)

    Langella, Stephen; Oster, Scott; Hastings, Shannon; Siebenlist, Frank; Phillips, Joshua; Ervin, David; Permar, Justin; Kurc, Tahsin; Saltz, Joel

    2007-01-01

    Security is a high priority issue in medical domain, because many institutions performing biomedical research work with sensitive medical data regularly. This issue becomes more complicated, when it is desirable or needed to access and analyze data in a multi-institutional setting. In the NCI cancer Biomedical Informatics Grid (caBIG™) program, several security issues were raised that existing security technologies could not address. Considering caBIG is envisioned to span a large number of cancer centers and investigator laboratories, these issues pose considerable challenge. In this paper we present these issues and the infrastructure, referred to as GAARDS, which has been developed to address them. PMID:18693873

  13. Development of new dosemeters of CaSO4

    International Nuclear Information System (INIS)

    Santos, Ana Gabryele M. dos; Junot, Danilo O.; Souza, Divanizia N.

    2016-01-01

    Thermoluminescent dosimeters (TLDs) are widely used in in vivo dosimetry because of their simple production, viability for dose determination in difficult geometries and their reusability. The motivation of this work was to produce CaSO 4 crystals doped with thulium (Tm) and analyze their thermoluminescent (TL) properties. The crystals were produced by a variation of slow evaporation route, and TL curves showed emission peaks centered around 190 ° C and 320 ° C after irradiation with a 90 Sr / 90 Y source. Thermoluminescent properties such as linearity, reproducibility and fading were evaluated. The CaSO 4 :Tm samples produced proved feasible for dosimetry purposes. (author)

  14. Large magnetoresistance in La-Ca-Mn-O films

    International Nuclear Information System (INIS)

    Chen, L.H.; Jin, S.; Tiefel, T.H.; Ramesh, R.; Schurig, D.

    1995-01-01

    A very large magnetoresistance value in excess of 10 6 % has been obtained at 110 K, H = 6 T in La-Ca-Mn-O thin films epitaxially grown on LaAlO 3 substrates by pulsed laser deposition. The as-deposited film exhibits a substantial magnetoresistance value of 39,000%, which is further improved by heat treatment. A strong dependence of the magnetoresistance on film thickness was observed, with the value reduced by orders of magnitude when the film is made thicker than ∼2,000 angstrom. This behavior is interpreted in terms of lattice strain in the La-Ca-Mn-O films

  15. Site Environmental Report for 2014 SNL/CA

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Barbara L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-06-01

    Sandia National Laboratories, California (SNL/CA) is a government-owned/contractoroperated laboratory. Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, manages and operates the laboratory for the Department of Energy’s National Nuclear Security Administration (NNSA). The NNSA Sandia Field Office administers the contract and oversees contractor operations at the site. This Site Environmental Report for 2014 was prepared in accordance with DOE Order 231.1B, Environment, Safety and Health Reporting (DOE 2011d). The report provides a summary of environmental monitoring information and compliance activities that occurred at SNL/CA during calendar year 2014. General site and environmental program information is also included.

  16. EFFECT OF FERRITE PHASE ON THE FORMATION AND COEXISTENCE OF 3CaO.3Al₂O₃.CaSO₄ AND 3CaO.SiO₂ MINERALS

    Directory of Open Access Journals (Sweden)

    Xiaolei Lu

    2017-12-01

    Full Text Available The effect of ferrite on the formation and coexistence of 3CaO.3Al₂O₃.CaSO₄ (C₄A₃$ and 3CaO.SiO₂ (C3S was investigated in this paper. The results indicate that 20 % content of ferrite phase with the composition of C₂A0.5F0.5 can facilitate the coexistence of C₄A₃$ and C₃S solid solutions at 1350 ° C. There are other trace elements that incorporate into clinker minerals and form solid solutions. In addition, the dark and polygonal C₄A₃$ solid solution is not dissolved in liquid phase at 1350 ° C. It can promote the burnability of the raw mixes and provide a favorable condition for the formation of C₃S. However, it has an adverse effect on the coexistence of two clinker minerals with the changing of ferrite compositions. This will provide the important basis for the preparation of the calcium sulphoaluminate cement clinker containing C₃S.

  17. Effect of ionizing radiation on Ca2+-ATPase and Mg2+-ATPase: the role of ligands

    International Nuclear Information System (INIS)

    Dreval', V.I.

    1994-01-01

    The change of Ca 2+ -ATPase and Mg 2+ -ATPase activity in plasma membranes of thymocytes irradiated with doses of 10 2 , 10 3 and 10 4 Gy in the presence of Ca 2+ , Mg 2+ and ATP was studied. Stabilizing effect of Ca 2+ and Mg 2+ on Ca 2+ -ATPase and ATP on Mg 2+ -ATPase under irradiation was established

  18. Exchangers man the pumps: Functional interplay between proton pumps and proton-coupled Ca(2+) exchangers

    Science.gov (United States)

    Tonoplast-localised proton-coupled Ca(2+) transporters encoded by cation/H(+) exchanger (CAX) genes play a critical role in sequestering Ca(2+) into the vacuole. These transporters may function in coordination with Ca(2+) release channels, to shape stimulus-induced cytosolic Ca(2+) elevations. Recen...

  19. Age-dependent alterations in Ca2+ homeostasis: role of TRPV5 and TRPV6.

    NARCIS (Netherlands)

    Abel, M. van; Huybers, S.; Hoenderop, J.G.J.; Kemp, J.W.C.M. van der; Leeuwen, J.P.P.M. van; Bindels, R.J.M.

    2006-01-01

    Aging is associated with alterations in Ca2+ homeostasis, which predisposes elder people to hyperparathyroidism and osteoporosis. Intestinal Ca2+ absorption decreases with aging and, in particular, active transport of Ca2+ by the duodenum. In addition, there are age-related changes in renal Ca2+

  20. Internal Ca2+ mobilization and secretion in bovine adrenal chromaffin cells

    DEFF Research Database (Denmark)

    Cheek, T R; Thastrup, Ole

    1989-01-01

    and the sesquiterpene lactone thapsigargin (TG), which releases internal Ca2+ without concomitant breakdown of inositol lipids or protein kinase C activation, to examine the events which follow depletion of the releasable Ca2+ store in these cells. Monitoring [Ca2+]i using Fura-2 demonstrated that TG released Ca2+ from...

  1. (CaA)SiO3 [A = Ba or Sr] phosphors

    Indian Academy of Sciences (India)

    Unknown

    378 terized by photoluminescence (PL), X-ray diffraction. (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM) techniques. 2. Experimental. Eu doped CaSiO3, (Ca, Ba) SiO3 and (Ca, Sr) SiO3 pow- ders were prepared by sol–gel technique. Analar grade powder CaCO3, tetra ethyl orthosilicate ...

  2. ISOLASI DAN KARAKTERISASI CaO (KALSIUM OKSIDA) DARI CANGKANG KERANG DARAH (Anadara Granosa)

    OpenAIRE

    yahya, afdaliah

    2014-01-01

    Seashells from species Anadara Granosa were used as raw materials to isolate CaO by calcination at temperatures of 1000 ?? C for 5 hours to obtain the CaO content is 99.61%. This process can take place due to the conversion of CaCO3 into CaO

  3. Purinergic receptors stimulate Na+/Ca2+ exchange in pancreatic duct cells: possible role of proteins handling and transporting Ca2+

    DEFF Research Database (Denmark)

    Hansen, Mette R; Krabbe, Simon; Ankorina-Stark, Ieva

    2009-01-01

    Most purinergic receptors activate intracellular Ca(2+) signalling, and in epithelia they stimulate transport of major ions. Aim of the present study on pancreatic ducts was to find whether P2 receptors also regulate cellular Ca(2+) transport, such as that via the Na(+)/Ca(2+) exchanger (NCX......). Since NCX can also be connected with epithelial Ca(2+) transport, we also investigated expression of some Ca(2+)-handling/transporting proteins. Expression analysis revealed that pancreatic ducts of rat and human duct cell line CFPAC-1 (also PANC-1 and Capan-1) express the Na(+)/Ca(2+) exchanger (splice...... in human and rat duct cells. Application of ATP to CFPAC-1 monolayers also stimulated Ca(2+) transport from the luminal to the basolateral side. Taken together, these results show that pancreatic ducts express a number of Ca(2+)-handling/transporting proteins and we propose that these together...

  4. Clinical significance of determination of changes of serum CA153, CA125 and TSGF levels after operation in patients with breast cancer

    International Nuclear Information System (INIS)

    Zhou Jun; Wang Zhaoxin; Wang Yan; Wang Rui

    2007-01-01

    Objective: To study the clinical significance of changes serum CA153, CA125 and TSGF levels after operation in patients with breast cancer. Methods: Serum CA153, CA125 and TSGF (with RIA) and serum TSGF levels (with biochemistry method) were measured in 36 patients with breast cancer both before and after operation as well as in 35 controls. Results: Before operation, serum levels of serum CA153, CA125 and TSGF in the patients were significantly higher than those in the controls (P < 0.01 ). One month after operation, all the levels were approaching normal. Six months later, the levels in the patients without recurrence remained normal, however, the levels in the 4 patients with recurrence returned to those before operation again. Conclusion: Changes of serum CA153, CA125 and TSGF levels are closely related to the tumor burden and if levels were high after operation, may indicate the presence of recurrence. (authors)

  5. Nuclear structure of light Ca and heavy Cr isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Buerger, A.

    2007-07-01

    In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the predicted value. A remaining difference might be due to emission of protons which cannot be detected with the present experimental setup. Both the branching ratio and the large excitation energy are compatible with a large N=16 gap in {sup 36}Ca that leads to relatively pure configurations both in the ground state and the excited 2{sup +} state. As a by-product of the experiment, two excitation energies in the T=2 nuclei {sup 32}Ar and {sup 28}S have been confirmed, and two {gamma}-ray transitions have been observed for the first time in {sup 37}Ca. While the mirror energy differences in the T=2 pairs {sup 36}Ca-{sup 36}S, {sup 32}Ar-{sup 32}Si, and {sup 28}S-{sup 28}Mg can be reproduced in shell model calculations using a modified USD interaction, these modifications are not sufficient to explain the mirror energy differences for the pair {sup 37}Ca-{sup 37}Cl. In the heavy Cr isotopes, new experimental evidence for a sub-shell closure at N=32 was found in a measurement of B(E2) values using high

  6. Dynamic immobilization of simulated radionuclide 133Cs in soil by thermal treatment/vitrification with nanometallic Ca/CaO composites

    International Nuclear Information System (INIS)

    Mallampati, Srinivasa Reddy; Mitoma, Yoshiharu; Okuda, Tetsuji; Simion, Cristian; Lee, Byeong Kyu

    2015-01-01

    Although direct radiation induced health impacts were considered benign, soil contamination with 137 Cs, due to its long-term radiological impact (30 years half-life) and its high biological availability is of a major concern in Japan in the aftermath of the Fukushima nuclear power plant disaster. Therefore 137 Cs reduction and immobilization in contaminated soil are recognized as important problems to be solved using suitable and effective technologies. One such thermal treatment/vitrification with nanometallic Ca/CaO amendments is a promising treatment for the ultimate immobilization of simulated radionuclide 133 Cs in soil, showing low leachability and zero evaporation. Immobilization efficiencies were 88%, 95% and 96% when the 133 Cs soil was treated at 1200 °C with activated carbon, fly ash and nanometallic Ca/CaO additives. In addition, the combination of nanometallic Ca/CaO and fly ash (1:1) enhanced the immobilization efficiency to 99%, while no evaporation of 133 Cs was observed. At lower temperatures (800 °C) the leachable fraction of Cs was only 6% (94% immobilization). Through the SEM–EDS analysis, decrease in the amount of Cs mass percent detectable on soil particle surface was observed after soil vitrified with nCa/CaO + FA. The 133 Cs soil was subjected to vitrified with nCa/CaO + FA peaks related to Ca, crystalline phases (CaCO 3 /Ca(OH) 2 ), wollastonite, pollucite and hematite appeared in addition to quartz, kaolinite and bentonite, which probably indicates that the main fraction of enclosed/bound materials includes Ca-associated complexes. Thus, the thermal treatment with the addition of nanometallic Ca/CaO and fly ash may be considered potentially applicable for the remediation of radioactive Cs contaminated soil at zero evaporation, relatively at low temperature. - Graphical abstract: SEM–EDS element maps of 133 Cs contaminated soil before and after thermal treatment at 1200 °C with different addictives. Color intensity for Cs is from 0

  7. caGrid 1.0: A Grid Enterprise Architecture for Cancer Research

    Science.gov (United States)

    Oster, Scott; Langella, Stephen; Hastings, Shannon; Ervin, David; Madduri, Ravi; Kurc, Tahsin; Siebenlist, Frank; Covitz, Peter; Shanbhag, Krishnakant; Foster, Ian; Saltz, Joel

    2007-01-01

    caGrid is the core Grid architecture of the NCI-sponsored cancer Biomedical Informatics Grid (caBIGTM) program. The current release, caGrid version 1.0, is developed as the production Grid software infrastructure of caBIGTM. Based on feedback from adopters of the previous version (caGrid 0.5), it has been significantly enhanced with new features and improvements to existing components. This paper presents an overview of caGrid 1.0, its main components, and enhancements over caGrid 0.5. PMID:18693901

  8. caGrid 1.0: a Grid enterprise architecture for cancer research.

    Science.gov (United States)

    Oster, Scott; Langella, Stephen; Hastings, Shannon; Ervin, David; Madduri, Ravi; Kurc, Tahsin; Siebenlist, Frank; Covitz, Peter; Shanbhag, Krishnakant; Foster, Ian; Saltz, Joel

    2007-10-11

    caGrid is the core Grid architecture of the NCI-sponsored cancer Biomedical Informatics Grid (caBIG) program. The current release, caGrid version 1.0, is developed as the production Grid software infrastructure of caBIG. Based on feedback from adopters of the previous version (caGrid 0.5), it has been significantly enhanced with new features and improvements to existing components. This paper presents an overview of caGrid 1.0, its main components, and enhancements over caGrid 0.5.

  9. Assembly of a Tyr122 Hydrophobic Cluster in Sarcoplasmic Reticulum Ca2+-ATPase Synchronizes Ca2+ Affinity Reduction and Release with Phosphoenzyme Isomerization*

    Science.gov (United States)

    Yamasaki, Kazuo; Daiho, Takashi; Danko, Stefania; Suzuki, Hiroshi

    2015-01-01

    The mechanism whereby events in and around the catalytic site/head of Ca2+-ATPase effect Ca2+ release to the lumen from the transmembrane helices remains elusive. We developed a method to determine deoccluded bound Ca2+ by taking advantage of its rapid occlusion upon formation of E1PCa2 and of stabilization afforded by a high concentration of Ca2+. The assay is applicable to minute amounts of Ca2+-ATPase expressed in COS-1 cells. It was validated by measuring the Ca2+ binding properties of unphosphorylated Ca2+-ATPase. The method was then applied to the isomerization of the phosphorylated intermediate associated with the Ca2+ release process E1PCa2 → E2PCa2 → E2P + 2Ca2+. In the wild type, Ca2+ release occurs concomitantly with EP isomerization fitting with rate-limiting isomerization (E1PCa2 → E2PCa2) followed by very rapid Ca2+ release. In contrast, with alanine mutants of Leu119 and Tyr122 on the cytoplasmic part of the second transmembrane helix (M2) and Ile179 on the A domain, Ca2+ release in 10 μm Ca2+ lags EP isomerization, indicating the presence of a transient E2P state with bound Ca2+. The results suggest that these residues function in Ca2+ affinity reduction in E2P, likely via a structural rearrangement at the cytoplasmic part of M2 and a resulting association with the A and P domains, therefore leading to Ca2+ release. PMID:26442589

  10. Sodium-calcium exchanger and R-type Ca2+ channels mediate spontaneous [Ca2+](i) oscillations in magnocellular neurones of the rat supraoptic nucleus

    Czech Academy of Sciences Publication Activity Database

    Kortus, Štěpán; Srinivasan, Ch.; Forostyak, O.; Zápotocký, Martin; Ueta, Y.; Syková, E.; Chvátal, A.; Verkhratsky, A.; Dayanithi, G.

    2016-01-01

    Roč. 59, č. 6 (2016), s. 289-298 ISSN 0143-4160 R&D Projects: GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:67985823 Keywords : magnocellular neurosecretory cells * voltage-gated Ca2+ channels * intracellular Ca2+ stores * Ca2+ imaging * Ca2+ oscillations Subject RIV: FH - Neurology Impact factor: 3.707, year: 2016

  11. Protein fingerprints of cultured CA3-CA1 hippocampal neurons: comparative analysis of the distribution of synaptosomal and cytosolic proteins

    Directory of Open Access Journals (Sweden)

    Cerutti Sergio

    2008-04-01

    Full Text Available Abstract Background All studies aimed at understanding complex molecular changes occurring at synapses face the problem of how a complete view of the synaptic proteome and of its changes can be efficiently met. This is highly desirable when synaptic plasticity processes are analyzed since the structure and the biochemistry of neurons and synapses get completely reshaped. Because most molecular studies of synapses are nowadays mainly or at least in part based on protein extracts from neuronal cultures, this is not a feasible option: these simplified versions of the brain tissue on one hand provide an homogeneous pure population of neurons but on the other yield only tiny amounts of proteins, many orders of magnitude smaller than conventional brain tissue. As a way to overcome this limitation and to find a simple way to screen for protein changes at cultured synapses, we have produced and characterized two dimensional electrophoresis (2DE maps of the synaptic proteome of CA3-CA1 hippocampal neurons in culture. Results To obtain 2D maps, hippocampal cultures were mass produced and after synaptic maturation, proteins were extracted following subfractionation procedures and separated by 2D gel electrophoresis. Similar maps were obtained for the crude cytosol of cultured neurons and for synaptosomes purified from CA3-CA1 hippocampal tissue. To efficiently compare these different maps some clearly identifiable reference points were molecularly identified by mass spectrometry and immunolabeling methods. This information was used to run a differential analysis and establish homologies and dissimilarities in these 2D protein profiles. Conclusion Because reproducible fingerprints of cultured synapses were clearly obtained, we believe that our mapping effort could represent a simple tool to screen for protein expression and/or protein localization changes in CA3-CA1 hippocampal neurons following plasticity.

  12. The Na+/Ca2+exchanger and the Plasma Membrane Ca2+-ATPase in β-cell function and diabetes.

    Science.gov (United States)

    Herchuelz, André; Pachera, Nathalie

    2018-01-10

    The rat pancreatic β-cell expresses 6 splice variants of the Plasma Membrane Ca 2+ -ATPase (PMCA) and two splice variants of the Na + /Ca 2+ exchanger 1 (NCX1). In the β-cell Na + /Ca 2+ exchange displays a high capacity, contributes to both Ca 2+ outflow and influx and participates to the control of insulin release. Gain of function studies show that overexpression of PMCA2 or NCX1 leads to endoplasmic reticulum (ER) Ca 2+ depletion with subsequent ER stress, decrease in β-cell proliferation and β-cell death by apoptosis. Loss of function studies show, on the contrary, that heterozygous inactivation of NCX1 (Ncx1 +/- ) leads to an increase in β-cell function and a 5 fold increase in both β-cell mass and proliferation. The mutation also increases β-cell resistance to hypoxia, and Ncx1 +/- islets show a 2-4 times higher rate of diabetes cure than Ncx1 +/+ islets when transplanted in diabetic animals. Thus, down-regulation of the Na + /Ca 2+ exchanger leads to various changes in β-cell function that are opposite to the major abnormalities seen in diabetes. In addition, the β-cell includes the mutually exclusive exon B in the alternative splicing region of NCX1, which confers a high sensitivity of its NCX splice variants (NCX1.3 & 1.7) to the inhibitory action of compounds like KBR-7943. Heterozygous inactivation of PMCA2 leads to apparented, though not completely similar results.These provide 2 unique models for the prevention and treatment of β-cell dysfunction in diabetes and following islet transplantation. Copyright © 2017. Published by Elsevier B.V.

  13. Coral Cd/Ca and Mn/Ca records of ENSO variability in the Gulf of California

    Directory of Open Access Journals (Sweden)

    J. D. Carriquiry

    2010-06-01

    Full Text Available We analyzed the trace element ratios Cd/Ca and Mn/Ca in three coral colonies (Porites panamensis (1967–1989, Pavona clivosa (1967–1989 and Pavona gigantea (1979–1989 from Cabo Pulmo reef, Southern Gulf of California, Mexico, to assess the oceanographic changes caused by El Niño – Southern Oscillation (ENSO events in the Eastern Tropical North Pacific (ETNP. Interannual variations in the coral Cd/Ca and Mn/Ca ratios showed clear evidence that incorporation of Cd and Mn in the coral skeleton was influenced by ENSO conditions, but the response for each metal was controlled by different processes. The Mn/Ca ratios were significantly higher during ENSO years (p<0.05 relative to non-ENSO years for the three species of coral. In contrast, the Cd/Ca was systematically lower during ENSO years, but the difference was significant (p<0.05 only in Pavona gigantea. A decrease in the incorporation of Cd and a marked increase in Mn indicated strongly reduced vertical mixing in the Gulf of California during the mature phase of El Niño. The oceanic warming during El Niño events produces a relaxation of upwelling and a stabilization of the thermocline, which may act as a physical barrier limiting the transport of Cd from deeper waters into the surface layer. In turn, this oceanic condition can increase the residence time of particulate-Mn in surface waters, allowing an increase in the photo-reduction of particulate-Mn and the release of available Mn into the dissolved phase. These results support the use of Mn/Ca and Cd/Ca ratios in biogenic carbonates as tracers of increases in ocean stratification and trade wind weakening and/or collapse in the ETNP during ENSO episodes.

  14. The functional genome of CA1 and CA3 neurons under native conditions and in response to ischemia

    Directory of Open Access Journals (Sweden)

    Rossner Moritz

    2007-10-01

    Full Text Available Abstract Background The different physiological repertoire of CA3 and CA1 neurons in the hippocampus, as well as their differing behaviour after noxious stimuli are ultimately based upon differences in the expressed genome. We have compared CA3 and CA1 gene expression in the uninjured brain, and after cerebral ischemia using laser microdissection (LMD, RNA amplification, and array hybridization. Results Profiling in CA1 vs. CA3 under normoxic conditions detected more than 1000 differentially expressed genes that belong to different, physiologically relevant gene ontology groups in both cell types. The comparison of each region under normoxic and ischemic conditions revealed more than 5000 ischemia-regulated genes for each individual cell type. Surprisingly, there was a high co-regulation in both regions. In the ischemic state, only about 100 genes were found to be differentially expressed in CA3 and CA1. The majority of these genes were also different in the native state. A minority of interesting genes (e.g. inhibinbetaA displayed divergent expression preference under native and ischemic conditions with partially opposing directions of regulation in both cell types. Conclusion The differences found in two morphologically very similar cell types situated next to each other in the CNS are large providing a rational basis for physiological differences. Unexpectedly, the genomic response to ischemia is highly similar in these two neuron types, leading to a substantial attenuation of functional genomic differences in these two cell types. Also, the majority of changes that exist in the ischemic state are not generated de novo by the ischemic stimulus, but are preexistant from the genomic repertoire in the native situation. This unexpected influence of a strong noxious stimulus on cell-specific gene expression differences can be explained by the activation of a cell-type independent conserved gene-expression program. Our data generate both novel

  15. Dielectron production in Ca+Ca collisions at 1. 0 and 2. 0 A GeV

    Energy Technology Data Exchange (ETDEWEB)

    Roche, G.; Krebs, G.F.; Letessier-Selvon, A.; Matis, H.S.; Naudet, C.; Schroeder, L.S.; Seidl, P.A.; Yegneswaran, A. (Lawrence Berkeley Lab., CA (USA)); Bystricky, J.; Carroll, J.; Gordon, J.; Igo, G. (California Univ., Los Angeles (USA)); Hallman, T.; Madansy, L.; Welsh, R. (Johns Hopkins Univ., Baltimore, MD (USA)); Kirk, P.; Wang, Z.F. (Louisiana State Univ., Baton Rouge (USA)); Landaud, G. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France)); Miller, D. (Northwestern Univ., Evanston, IL (USA)); DLS Collaboration

    1989-08-10

    Dileptons should be a good probe of the early stage of nucleus-nucleus collisions and may carry information on pion dynamics in nuclear matter. We have observed a dielectron signal well above estimated contributions from Dalitz decays of particles or resonances. At 1.0 A GeV, the dielectron mass spectrum is significantly different for Ca+Ca and p+Be reactions. The dielectron yield scales as the first power of the product of the projectile and target masses. (orig.).

  16. L-type Ca2+ channel blockers promote Ca2+ accumulation when dopamine receptors are activated in striatal neurons

    OpenAIRE

    Eaton, Molly E.; Macías, Wendy; Youngs, Rachael M.; Rajadhyaksha, Anjali; Dudman, Joshua T.; Konradi, Christine

    2004-01-01

    Dopamine (DA) receptor-mediated signal transduction and gene expression play a central role in many brain disorders from schizophrenia to Parkinson’s disease to addiction. While trying to evaluate the role of L-type Ca2+ channels in dopamine D1 receptor-mediated phosphorylation of the transcription factor cyclic AMP response element-binding protein (CREB), we found that activation of dopamine D1 receptors alters the properties of L-type Ca2+ channel inhibitors and turns them into facilitators...

  17. Low temperature synthesis of CaZrO3 nanoceramics from CaCl2–NaCl molten eutectic salt

    Directory of Open Access Journals (Sweden)

    Rahman Fazli

    2015-06-01

    Full Text Available CaZrO3 nanoceramics were successfully synthesized at 700 C using the molten salt method, and the effects of processing parameters, such as temperature, holding time, and amount of salt on the crystallization of CaZrO3 were investigated. CaCl2, Na2CO3, and nano-ZrO2 were used as starting materials. On heating, CaCl2–NaCl molten eutectic salt provided a liquid medium for the reaction of CaCO3 and ZrO2 to form CaZrO3. The results demonstrated that CaZrO3 started to form at about 600C and that, after the temperature was increased to 1,000C, the amounts of CaZrO3 in the resultant powders increased with a concomitant decrease in CaCO3and ZrO2 contents. After washing with hot distilled water, the samples heated for 3 h at 700C were single-phase CaZrO3 with 90–95 nm particle size. Furthermore, the synthesized CaZrO3 particles retained the size and morphology of the ZrO2 powders which indicated that a template mechanism dominated the formation of CaZrO3 by molten-salt method.

  18. The effect of the PKC inhibitor GF109203X on the release of Ca2+ from internal stores and Ca2+ entry in DDT1 MF-2 cells

    NARCIS (Netherlands)

    Sipma, H; vanderZee, L; vandenAkker, J; denHertog, A; Nelemans, A

    1996-01-01

    1 The effect of the specific protein kinase C (PKC) inhibitor, GF109203X, were measured on the cytoplasmic Ca2+ concentration ([Ca2+](i)), and on histamine H-1 receptor- and thapsigargin-mediated increases in [Ca2+](i) in DDT1 MF-2 smooth muscle cells. 2 After pretreatment of cells with GF109203X (5

  19. Is otolith microchemistry (Sr: Ca and Ba:Ca ratios useful to identify Mugil curema populations in the southeastern Caribbean Sea?

    Directory of Open Access Journals (Sweden)

    E. Avigliano

    Full Text Available Abstract The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela. The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method. Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State were significantly different from ratios in La Guardia (north of the State. A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area.

  20. Is otolith microchemistry (Sr: Ca and Ba:Ca ratios) useful to identify Mugil curema populations in the southeastern Caribbean Sea?

    Science.gov (United States)

    Avigliano, E; Callicó-Fortunato, R; Buitrago, J; Volpedo, A V

    2015-11-01

    The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area.

  1. Intracellular [Ca2+] and Vo2 after manipulation of the free-energy of the Na+/Ca(2+)-exchanger in isolated rat ventricular myocytes

    NARCIS (Netherlands)

    Fiolet, J. W.; Baartscheer, A.; Schumacher, C. A.

    1995-01-01

    We have investigated whether the Na+/Ca(2+)-exchanger has a functional regulatory role in the control of oxidative metabolism in suspensions of isolated rat ventricular myocytes. Therefore we simultaneously measured intracellular [Ca2+] ([Ca2+]i) with Indo-1 and respiratory rate (Vo2) after abrupt

  2. Punta Pitt Stable Isotope and Ion Data (delta 18O, delta 13C, Cd/Ca, Mn/Ca) for 1936 to 1982.5

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File contains data presented by Shen et al. (1992a). Table includes d18O, d13C, Cd/Ca, Mn/Ca, and Ba/Ca data from a 2m coral head and, for comparison, SST records...

  3. Apo-states of calmodulin and CaBP1 control CaV1 voltage-gated calcium channel function through direct competition for the IQ domain

    Science.gov (United States)

    Findeisen, Felix; Rumpf, Christine; Minor, Daniel L.

    2013-01-01

    In neurons, binding of calmodulin (CaM) or calcium-binding protein 1 (CaBP1) to the CaV1 (L-type) voltage-gated calcium channel IQ domain endows the channel with diametrically opposed properties. CaM causes calcium-dependent inactivation (CDI) and limits calcium entry, whereas CaBP1 blocks CDI and allows sustained calcium influx. Here, we combine isothermal titration calorimetry (ITC) with cell-based functional measurements and mathematical modeling to show that these calcium sensors behave in a competitive manner that is explained quantitatively by their apo-state binding affinities for the IQ domain. This competition can be completely blocked by covalent tethering of CaM to the channel. Further, we show that Ca2+/CaM has a sub-picomolar affinity for the IQ domain that is achieved without drastic alteration of calcium binding properties. The observation that the apo-forms of CaM and CaBP1 compete with each other demonstrates a simple mechanism for direct modulation of CaV1 function and suggests a means by which excitable cells may dynamically tune CaV activity. PMID:23811053

  4. NPY and carbachol raise Ca2+ in SK-N-MC cells by three different mechanisms. Evidence for inositol phosphate-independent Ca2+ mobilization by NPY

    NARCIS (Netherlands)

    Michel, M. C.; Feth, F.; Stieneker, M.; Rascher, W.

    1992-01-01

    We have compared the mechanism of NPY- and carbachol-stimulated Ca2+ increases in SK-N-MC cells. NPY stimulated Ca2+ mobilization via a pertussis toxin-sensitive mechanism. Carbachol stimulated Ca2+ mobilization and influx via pertussis toxin-insensitive and -sensitive mechanisms, respectively.

  5. Serum CA 125 concentrations in women with endometriosis or ...

    African Journals Online (AJOL)

    endometriosis or uterine fibroids treated with gonadotrophin-releasing hormone agonist analogues z. M. VAN DER SPUY, M. WOOD, G. FIEGGEN, M. SALIE HENDRICKS. Abstract We assessed the possible role of CA 125 in the. Inonitoring of gonadotrophin-releasing hOrInone. (GnRH) agonist analogue therapy in women ...

  6. Enhanced antioxidant defense after exogenous application of Ca 2+ ...

    African Journals Online (AJOL)

    Both of these nutrients play an important role in ameliorating drought stress in crop plants. This experiment was designed to study whether exogenous application of Ca2+ and K+ before the drought could enhance the potential of plants to survive under limiting water conditions. Brassica napus L. cv Bulbul-98 seedlings ...

  7. Improved limits on beta(-) and beta(-) decays of Ca-48

    Czech Academy of Sciences Publication Activity Database

    Bakalyarov, A.; Balysh, A.; Barabash, AS.; Beneš, P.; Briancon, C.; Brudanin, V. B.; Čermák, P.; Egorov, V.; Hubert, F.; Hubert, P.; Korolev, NA.; Kosjakov, VN.; Kovalík, Alojz; Lebedev, NA.; Novgorodov, A. F.; Rukhadze, NI.; Štekl, NI.; Timkin, VV.; Veleshko, IE.; Vylov, T.; Umatov, VI.

    2002-01-01

    Roč. 76, č. 9 (2002), s. 545-547 ISSN 0021-3640 Institutional research plan: CEZ:AV0Z1048901 Keywords : beta decay * double beta decay * Ca-48 Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.483, year: 2002

  8. DISTRIBUTION OF MAJOR ELEMENTS (NA, K, CA, MG) IN THE ...

    African Journals Online (AJOL)

    Levels of sodium, potassium, calcium and magnesium were determined in plant organs (bud, flowers, fruit, seed, leaves, stems, roots, cobs, styles, shaft, grains and efflorescences) of three Fadama farms located in Ifaki-Ekiti, Ado-Ekiti and Ikere-Ekiti of Ekiti State, Nigeria. The highest levels of Mg, K, Na and Ca were ...

  9. Structural, dielectric and piezoelectric study of Ca-, Zr-modified ...

    Indian Academy of Sciences (India)

    2017-08-22

    Aug 22, 2017 ... Structural, dielectric and piezoelectric study of Ca-, Zr-modified. BaTiO3 lead-free ceramics ... small amounts of Zr4+ can affect the crystal structure and microstructure as well as dielectric and piezoelectric properties of BaTiO3. ..... We would like to thank PHC Toubkal for the financial support. References.

  10. Structural and magnetic properties of the layered compound Ca2 ...

    Indian Academy of Sciences (India)

    ter physics due to the interesting physical properties revealed by them. Among the low dimensional magnetic materials, two-dimensional compounds of the type. A3B B2O8 (A = La, Ca, Sr, Y and (B ,B) = alkali or transition metal ions) have recently attracted a lot of interest [1–5]. These compounds crystallize in the or-.

  11. 76 FR 2799 - Amendment of Jet Route J-93; CA

    Science.gov (United States)

    2011-01-18

    ...; Airspace Docket No. 10-AWP-4] RIN 2120-AA66 Amendment of Jet Route J-93; CA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Jet Route J-93 in California between...) to amend J-93, (75 FR 66344). Interested parties were invited to participate in this rulemaking...

  12. 75 FR 66344 - Amendment of Jet Route J-93; CA

    Science.gov (United States)

    2010-10-28

    ...-1022; Airspace Docket No. 10-AWP-4] RIN 2120-AA66 Amendment of Jet Route J-93; CA AGENCY: Federal... proposes to amend Jet Route J-93 in California between the Julian VHF Omnidirectional Radio Range Tactical... is necessary to realign Jet Route J-93 with the revised location of the Penasco VOR. The Proposal The...

  13. SELECTIVE TRANSFORMATIONS OF THE CA-2+ PUMP INHIBITOR THAPSIGARGIN

    DEFF Research Database (Denmark)

    Andersen, A.; Cornett, Claus; Lauridsen, A.

    1994-01-01

    The importance of the sesquiterpene lactone thapsigargin as a tool for studying Ca2+ homeostasis has created a need for structure-activity relationship studies and consequently for procedures for selective transformations of the functional groups in the molecule. Methods for the selective inversi...

  14. Fetal injury induced by Ca-DTPA in dogs

    International Nuclear Information System (INIS)

    Taylor, G.N.; Mays, C.W.

    1978-01-01

    The chelating agent Ca-DTPA, used to remove plutonium from the body, has produced fetal deaths and deformities in mice and rats. Damage is caused by depletion of essential trace elements, particularly zinc and manganese. It is suggested that a relationship may exist between the daily amount of Ca-DTPA,per kg body weight needed,to produce fetal toxicity and the daily intake of dietary zinc per kg body weight, and that this relationship could be used to predict fetal toxicity thresholds in various species. Results of a study on beagles are presented. Ca-DTPA treatment at the dose levels used in human therapy did not produce any symptoms in the pregnant dams but the fetuses showed depressed birth weight, abnormal hair colour due to pigmentary deficiency, brain damage and neutropenia. Extrapolation from dogs to humans predicts a toxic fetal dose less that one sixth of the daily dosage presently used for an adult woman, and emphasizes the hazards of Ca-DTPA therapy during pregnancy. (author)

  15. Synthesis of BiPbSrCaCuO superconductor

    Science.gov (United States)

    Hults, William L.; Kubat-Martin, Kimberly A.; Salazar, Kenneth V.; Phillips, David S.; Peterson, Dean E.

    1994-01-01

    A process and a precursor composition for preparing a lead-doped bismuth-strontium-calcium-copper oxide superconductor of the formula Bi.sub.a Pb.sub.b Sr.sub.c Ca.sub.d Cu.sub.e O.sub.f wherein a is from about 1.7 to about 1.9, b is from about 0.3 to about 0.45, c is from about 1.6 to about 2.2, d is from about 1.6 to about 2.2, e is from about 2.97 to about 3.2 and f is 10.+-.z by reacting a mixture of Bi.sub.4 Sr.sub.3 Ca.sub.3 Cu.sub.4 O.sub.16.+-.z, an alkaline earth metal cuprate, e.g., Sr.sub.9 Ca.sub.5 Cu.sub.24 O.sub.41, and an alkaline earth metal plumbate, e.g., Ca.sub.2-x Sr.sub.x PbO.sub.4 wherein x is about 0.5, is disclosed.

  16. Mechanical and microstructure studies on the modification of CA film ...

    Indian Academy of Sciences (India)

    Unknown

    synthetic and biodegradable polymers will impart novel physical characteristics to the materials which can be ... most important organic ester of cellulose owing to its extensive applications in fibre, plastics and coatings. .... biodegradable material like CA, and a use and throw polymeric material so that the resultant product is ...

  17. CaII Κ Imaging to Understand UV Irradiance Variability

    Indian Academy of Sciences (India)

    tribpo

    agencies responsible for CaII emission are: the plages, the network, and the intranet work elements. The changes in the network and intranetwork elements related to solar activity are less understood, especially because of the lack of systematic and quantitative measurements of these chromospheric features. In our earlier ...

  18. Construction of CaF2-appended PVA nanofibre scaffold

    Indian Academy of Sciences (India)

    2018-02-02

    Feb 2, 2018 ... Construction of CaF2-appended PVA nanofibre scaffold. JIA XU1,2,3,∗. , JIANFENG MA1,3,4, YAN HE5, CHUNHONG LIU2 and QINGSONG YE3,5. 1College of Medicine and Dentistry, James Cook University, Cairns 4878, Australia. 2Key Laboratory of Applied Chemistry and Nanotechnology at ...

  19. CaII Κ Imaging to Understand UV Irradiance Variability

    Indian Academy of Sciences (India)

    tribpo

    (NSO/Sac Peak). The main purpose of the present paper is to separate and to derive the relative intensity and area of various chromospheric features from 424 ... 2. Results and discussion. To analyze the CaII Κ spectroheliograms and to separate various chromospheric magnetic features, we have calculated histograms ...

  20. CA for SLA: Arguments from the Chinese Language Classroom

    Science.gov (United States)

    He, Agnes Weiyun

    2004-01-01

    When the seminal article on the organization of turn-taking by Sacks, Schegloff, and Jefferson (1974) was published 30 years ago, I started learning English as a foreign language. In addition to being a learner of the English language for many years, I was also trained in the traditions of Conversation Analysis (CA) and linguistic anthropology…

  1. Construction of CaF2-appended PVA nanofibre scaffold

    Indian Academy of Sciences (India)

    2018-02-02

    Feb 2, 2018 ... jing Tongguang Fine Chemicals Company. Calcium chloride. (CaCl2) was purchased from ... High Voltage Power Supply Limited Company, China). A piece of aluminium foil was placed towards the tip ... is applicable to the aqueous environment for cell culture as a scaffold. Figure4 shows wide-scan FTIR ...

  2. DISTRIBUTION OF MAJOR ELEMENTS (Na, K, Ca, Mg) IN THE ...

    African Journals Online (AJOL)

    a

    followed by their levels in Lycopersicon esculentum root: Mg (2734), K (1079), Na (2111) and Ca. (678). The levels of all the elements were highly varied in the anatomical parts of each plant and between the various plants. The index of bioaccumulation (ratio in plants/soil) was recorded for all the elements with all values ...

  3. Mechanism of the CO2-Ca(OH)2 reaction

    International Nuclear Information System (INIS)

    Chew, V.S.; Cheh, C.H.; Glass, R.W.

    1983-01-01

    Recent studies clearly showed the importance of moisture in achieving high Ca(OH) 2 absorbent utilization for removing CO 2 from gas streams at ambient temperatures. However, the role of moisture and the mechanism of the reaction was not well understood. This paper summarizes the results of a study of the mechanism of the CO 2 -Ca(OH) 2 reaction with emphasis on the role of moisture. The reaction between Ca(OH) 2 and CO 2 in moist N 2 was found to be first order with respect to the reactants with a rate constant of about 100 min -1 . At high humidities, the rate of reaction was chemically controlled, but at low humidities, the reaction rate was limited by the diffusion through the carbonate layer formed by the reaction. Calculations showed that capillary condensation could have occurred only in about 2% of the pore volume and was unlikely to have affected the reaction rate significantly by allowing the reaction to occur in the liquid phase. It was, therefore, concluded that the main role of moisture was to improve the Ca(OH) 2 utilization by lowering the resistance to diffusion through the carbonate layer

  4. 75 FR 857 - City of Banning, CA; Notice of Filing

    Science.gov (United States)

    2010-01-06

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL10-28-000] City of Banning, CA; Notice of Filing December 29, 2009. Take notice that on December 23, 2009, the City of Banning, California filed its seventh annual revision to its Transmission Revenue Balancing Account Adjustment, to...

  5. 76 FR 1151 - City of Banning, CA; Notice of Filing

    Science.gov (United States)

    2011-01-07

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. NJ11-8-000] City of Banning, CA; Notice of Filing December 30, 2010. Take notice that on December 22, 2010, the City of Banning, California (Banning) filed its annual revisions to is Transmission Revenue Balancing Account Adjustment and a...

  6. Isospin properties of electric dipole excitations in Ca-48

    NARCIS (Netherlands)

    Derya, V.; Savran, D.; Endres, J.; Harakeh, M. N.; Hergert, H.; Kelley, J. H.; Papakonstantinou, P.; Pietralla, N.; Ponomarev, V. Yu.; Roth, R.; Rusev, G.; Tonchev, A. P.; Tornow, W.; Wortche, H. J.; Zilges, A.

    2014-01-01

    Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus Ca-48 below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between

  7. Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

    NARCIS (Netherlands)

    Koho, K.A.; de Nooijer, L.J.; Fontanier, C.; Toyofuku, T.; Oguri, K.; Kitazato, H.; Reichart, G.-J.

    2017-01-01

    The Mn / Ca of calcium carbonate tests of living (rose-Bengal-stained) benthic foraminifera (Elphidium batialis, Uvigerina spp., Bolivina spissa, Nonionellina labradorica and Chilostomellina fimbriata) were determined in relation to pore water manganese (Mn) concentrations for the first time along a

  8. Absorption spectrum of Ca atoms attached to He4 nanodroplets

    Science.gov (United States)

    Hernando, Alberto; Barranco, Manuel; Mayol, Ricardo; Pi, Martí; Krośnicki, Marek

    2008-01-01

    Within density functional theory, we have obtained the structure of He4 droplets doped with neutral calcium atoms. These results have been used, in conjunction with newly determined ab initio Σ1 and Π1 Ca-He pair potentials, to address the 4s4pP11←4s2S01 transition of the attached Ca atom, finding a fairly good agreement with absorption experimental data. We have studied the drop structure as a function of the position of the Ca atom with respect to the center of mass of the helium moiety. The interplay between the density oscillations arising from the helium intrinsic structure and the density oscillations produced by the impurity in its neighborhood plays a role in the determination of the equilibrium state, and hence in the solvation properties of alkaline earth atoms. In a case of study, the thermal motion of the impurity within the drop surface region has been analyzed in a semiquantitative way. We have found that, although the atomic shift shows a sizable dependence on the impurity location, the thermal effect is statistically small, contributing by about 10% to the line broadening. The structure of vortices attached to the calcium atom has been also addressed, and its effect on the calcium absorption spectrum discussed. At variance with previous theoretical predictions, we conclude that spectroscopic experiments on Ca atoms attached to He4 drops will be likely unable to detect the presence of quantized vortices in helium nanodrops.

  9. Co-ordination Action on Ocean Energy (CA-OE)

    DEFF Research Database (Denmark)

    Tedd, James; Frigaard, Peter

    In October 2004, the Co-ordination Action on Ocean Energy (CA-OE) was launched, co-financed by the European Commission, under the Renewable Energy Technologies priority within the 6th Framework programme, contract number 502701, chaired by Kim Nielsen, Rambøll, Denmark. The project involves 41...

  10. Protection induced by external Ca 2+ application on proline ...

    African Journals Online (AJOL)

    treated (100 mM NaCl) mustard plant (Sinapis alba L.) was investigated in relation to ion uptake, proline, chlorophyll a&b, protein and ABA concentrations. Salinity treatment (100 mM NaCl) led to significant decreases in Ca2+& Kuptake and Chl. a&b ...

  11. Low work function of the Ca2N surface

    NARCIS (Netherlands)

    Uijttewaal, M.A.; de Wijs, G. A.; Groot, R.A. de

    2004-01-01

    Polymer diodes require cathodes that do not corrode the polymer but do have low work function to minimize the electron injection barrier. First-principles calculations demonstrate that the work function of the (1000) surface of the compound Ca2N is half an eV lower than that of the elemental metal

  12. Optochemokine Tandem for Light-Control of Intracellular Ca2.

    Directory of Open Access Journals (Sweden)

    Katrin Feldbauer

    Full Text Available An optochemokine tandem was developed to control the release of calcium from endosomes into the cytosol by light and to analyze the internalization kinetics of G-protein coupled receptors (GPCRs by electrophysiology. A previously constructed rhodopsin tandem was re-engineered to combine the light-gated Ca2+-permeable cation channel Channelrhodopsin-2(L132C, CatCh, with the chemokine receptor CXCR4 in a functional tandem protein tCXCR4/CatCh. The GPCR was used as a shuttle protein to displace CatCh from the plasma membrane into intracellular areas. As shown by patch-clamp measurements and confocal laser scanning microscopy, heterologously expressed tCXCR4/CatCh was internalized via the endocytic SDF1/CXCR4 signaling pathway. The kinetics of internalization could be followed electrophysiologically via the amplitude of the CatCh signal. The light-induced release of Ca2+ by tandem endosomes into the cytosol via CatCh was visualized using the Ca2+-sensitive dyes rhod2 and rhod2-AM showing an increase of intracellular Ca2+ in response to light.

  13. Burstein Moss effect in nanocrystalline CaS: Ce

    Indian Academy of Sciences (India)

    Administrator

    Burstein Moss effect in nanocrystalline CaS: Ce. GEETA SHARMA*, PUJA CHAWLA, S P LOCHAB. † and NAFA SINGH. Department of Physics, Kurukshetra University, Kurukshetra 136 119, India. †. Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067, India. MS received 27 July 2009; revised 16 ...

  14. Unresolved problems in superconductivity of CaC6

    NARCIS (Netherlands)

    Mazin, I.I.; Boen, L.; Dolgov, O.V.; Golubov, Alexandre Avraamovitch; Bachelet, G.B.; Giantomassi, M.; Andersen, O.K.

    2007-01-01

    We discuss the current status of the theory of the “high-temperature” superconductivity in intercalated graphites YbC6 and CaC6. We emphasize that while the general picture of conventional, phonon-driven superconductivity has already emerged and is generally accepted, there are still interesting

  15. Colossal Magnetoresistance in La-Y-Ca-Mn-O Films

    NARCIS (Netherlands)

    Chen, L.H.; Tiefel, T.H.; Jin, S.; Palstra, T.T.M.; Ramesh, R.; Kwon, C.

    1996-01-01

    Magnetoresistance behavior of La0.60Y0.07CaMnOx, thin films epitaxially grown on LaAlO3 has been investigated. The films exhibit colossal magnetoresistance with the MR ratio in excess of 10^8% at ~60K, H = 7T, which is the highest ever reported for thin film manganites. The partial substitution of

  16. Collective modes in Ca70Mg30 glass

    Indian Academy of Sciences (India)

    Unknown

    of interatomic potential in the solids, has been used to generate the collective modes in the Ca70Mg30 glass. A model potential is proposed to describe the effective interaction in the glass. Three different forms of the local field correction functions viz. Hartree, Taylor and Ichimaru and Utsumi are used to examine relative ...

  17. Hydration and dehydration of CaO / Ca(OH){sub 2} and CaCl{sub 2} / CaCl{sub 2} * 6 H{sub 2}O-TGA / DSC studies

    Energy Technology Data Exchange (ETDEWEB)

    Rammelberg, Holger U.; Opel, O.; Ross, S.; Ruck, W. [Leuphana Univ., Lueneburg (Germany). Inst. of Environmental Chemistry

    2011-07-01

    Thermal energy storage drives the change towards the use of renewable energy resources and energy efficiency. The1mal storage can be used for waste heat and solar thermal usage. Solar thermal systems work at temperatures between 120 C (space heating and hot tap water) and up to 600 C (CSP plants), where thermal energy storage is a key component. In comparison to most commonly used water or molten salt storage, thermochemical storage materials provide ten times or higher storage capacities per mass or volume and the ability to store heat for longer times without the need of insulation. Recently published results state MgCl{sub 2} * 6 H{sub 2}O and CaCl{sub 2} * 6 H{sub 2}O to be useful for space heating and hot tap water and Ca(OH){sub 2} for higher temperature levels. We reported earlier about our studies in MgCl{sub 2} * 6 H{sub 2}O as pure and composite materials. In this paper we discuss the cycling stability of CaCl{sub 2} * 6 H{sub 2}O and Ca(OH){sub 2}.

  18. Variant prostate carcinoma and elevated serum CA-125.

    Science.gov (United States)

    Bilen, Mehmet Asim; Reyes, Adriana; Bhowmick, Deb; Maa, April; Bast, Robert; Pisters, Louis L; Lin, Sue-Hwa; Logothetis, Christopher J; Tu, Shi-Ming

    2014-10-01

    About 10% of tumors derived from nongynecologic, noncoelomic tissues react with the OC125 antibody. Some patients with advanced prostate cancer were found to have elevated serum CA-125 level. We examined the clinical history of 11 patients with castration resistant prostate cancer and an elevated serum CA-125 level. Pathological review and immunohistochemical staining were performed on tumors from eight of these patients. Patients with advanced prostate cancer and an elevated serum CA-125 level responded to androgen ablative therapy (median duration, 27 months). They were predisposed to develop persistent or recurrent urinary symptoms and visceral metastases. Eight of 11 patients had a low or undetectable serum prostate-specific antigen level (≤ 4 ng/mL) or an elevated serum carcinoembryonic antigen level (> 6 ng/mL). In 3 of 7 patients whose specimens were available for further review, the tumors contained histologic features compatible with a diagnosis of ductal or endometrioid adenocarcinoma of the prostate. Patients with prostate cancer and an elevated serum CA-125 level have unique clinical and pathologic characteristics. Some of these patients possess tumors compatible with a subtype of prostate cancer known as ductal adenocarcinoma. Additional studies need to be performed to elucidate the biologic basis of the various subtypes of prostate cancer.

  19. Postmenopausal Meigs' Syndrome in Elevated CA-125: A Case Report.

    Science.gov (United States)

    Park, Jung-Woo; Bae, Jong Woon

    2015-04-01

    Meigs' syndrome is a benign ovarian tumor associated with ascites and pleural effusion. Elevated cancer antigen 125 (CA-125) in Meigs' syndrome is an unusual clinical condition reported in few cases. We report here on a 61-year-old woman who presented with dyspnea; in imaging assessment, a heterogeneous pelvic mass measuring 12 × 11 cm with ascitic fluid was reported. Pleural effusion was detected on Chest X-ray. Aspiration of pleural fluid showed no evidence of malignancy. CA-125 level was 347 IU/mL. The patient underwent laparotomy during which a mass measuring 12 × 11 cm was detected in her left adnexa. Histology showed ovarian thecoma. The mass was resected, and, after that, the symptoms disappeared and CA-125 level reached 19 IU/mL. The patient had experienced no problem after 12 months of follow up. Although postmenopausal women with ovarian tumor, ascites, pleural effusion, and elevation of CA-125 levels probably have malignant ovarian tumors, Meigs' syndrome must be considered in the differential diagnosis.

  20. Synaptic NMDA receptor-dependent Ca²⁺ entry drives membrane potential and Ca²⁺ oscillations in spinal ventral horn neurons.

    Science.gov (United States)

    Alpert, Michael H; Alford, Simon

    2013-01-01

    During vertebrate locomotion, spinal neurons act as oscillators when initiated by glutamate release from descending systems. Activation of NMDA receptors initiates Ca²⁺-mediated intrinsic membrane potential oscillations in central pattern generator (CPG) neurons. NMDA receptor-dependent intrinsic oscillations require Ca²⁺-dependent K⁺ (K(Ca)2) channels for burst termination. However, the location of Ca²⁺ entry mediating K(Ca)2 channel activation, and type of Ca²⁺ channel--which includes NMDA receptors and voltage-gated Ca²⁺ channels (VGCCs)--remains elusive. NMDA receptor-dependent Ca²⁺ entry necessitates presynaptic release of glutamate, implying a location at active synapses within dendrites, whereas VGCC-dependent Ca²⁺ entry is not similarly constrained. Where Ca²⁺ enters relative to K(Ca)2 channels is crucial to information processing of synaptic inputs necessary to coordinate locomotion. We demonstrate that Ca²⁺ permeating NMDA receptors is the dominant source of Ca²⁺ during NMDA-dependent oscillations in lamprey spinal neurons. This Ca²⁺ entry is synaptically located, NMDA receptor-dependent, and sufficient to activate K(Ca)2 channels at excitatory interneuron synapses onto other CPG neurons. Selective blockade of VGCCs reduces whole-cell Ca²⁺ entry but leaves membrane potential and Ca²⁺ oscillations unaffected. Furthermore, repetitive oscillations are prevented by fast, but not slow, Ca²⁺ chelation. Taken together, these results demonstrate that K(Ca)2 channels are closely located to NMDA receptor-dependent Ca²⁺ entry. The close spatial relationship between NMDA receptors and K(Ca)2 channels provides an intrinsic mechanism whereby synaptic excitation both excites and subsequently inhibits ventral horn neurons of the spinal motor system. This places the components necessary for oscillation generation, and hence locomotion, at glutamatergic synapses.

  1. Mutations in PIK3CA are infrequent in neuroblastoma

    International Nuclear Information System (INIS)

    Dam, Vincent; Morgan, Brian T; Mazanek, Pavel; Hogarty, Michael D

    2006-01-01

    Neuroblastoma is a frequently lethal pediatric cancer in which MYCN genomic amplification is highly correlated with aggressive disease. Deregulated MYC genes require co-operative lesions to foster tumourigenesis and both direct and indirect evidence support activated Ras signaling for this purpose in many cancers. Yet Ras genes and Braf, while often activated in cancer cells, are infrequent targets for activation in neuroblastoma. Recently, the Ras effector PIK3CA was shown to be activated in diverse human cancers. We therefore assessed PIK3CA for mutation in human neuroblastomas, as well as in neuroblastomas arising in transgenic mice with MYCN overexpressed in neural-crest tissues. In this murine model we additionally surveyed for Ras family and Braf mutations as these have not been previously reported. Sixty-nine human neuroblastomas (42 primary tumors and 27 cell lines) were sequenced for PIK3CA activating mutations within the C2, helical and kinase domain 'hot spots' where 80% of mutations cluster. Constitutional DNA was sequenced in cases with confirmed alterations to assess for germline or somatic acquisition. Additionally, Ras family members (Hras1, Kras2 and Nras) and the downstream effectors Pik3ca and Braf, were sequenced from twenty-five neuroblastomas arising in neuroblastoma-prone transgenic mice. We identified mutations in the PIK3CA gene in 2 of 69 human neuroblastomas (2.9%). Neither mutation (R524M and E982D) has been studied to date for effects on lipid kinase activity. Though both occurred in tumors with MYCN amplification the overall rate of PIK3CA mutations in MYCN amplified and single-copy tumors did not differ appreciably (2 of 31 versus 0 of 38, respectively). Further, no activating mutations were identified in a survey of Ras signal transduction genes (including Hras1, Kras2, Nras, Pik3ca, or Braf genes) in twenty-five neuroblastic tumors arising in the MYCN-initiated transgenic mouse model. These data suggest that activating

  2. Simulating Urban Growth Using a Random Forest-Cellular Automata (RF-CA Model

    Directory of Open Access Journals (Sweden)

    Courage Kamusoko

    2015-04-01

    Full Text Available Sustainable urban planning and management require reliable land change models, which can be used to improve decision making. The objective of this study was to test a random forest-cellular automata (RF-CA model, which combines random forest (RF and cellular automata (CA models. The Kappa simulation (KSimulation, figure of merit, and components of agreement and disagreement statistics were used to validate the RF-CA model. Furthermore, the RF-CA model was compared with support vector machine cellular automata (SVM-CA and logistic regression cellular automata (LR-CA models. Results show that the RF-CA model outperformed the SVM-CA and LR-CA models. The RF-CA model had a Kappa simulation (KSimulation accuracy of 0.51 (with a figure of merit statistic of 47%, while SVM-CA and LR-CA models had a KSimulation accuracy of 0.39 and −0.22 (with figure of merit statistics of 39% and 6%, respectively. Generally, the RF-CA model was relatively accurate at allocating “non-built-up to built-up” changes as reflected by the correct “non-built-up to built-up” components of agreement of 15%. The performance of the RF-CA model was attributed to the relatively accurate RF transition potential maps. Therefore, this study highlights the potential of the RF-CA model for simulating urban growth.

  3. Physiological and Pathological Roles of CaMKII-PP1 Signaling in the Brain

    Directory of Open Access Journals (Sweden)

    Norifumi Shioda

    2017-12-01

    Full Text Available Ca2+/calmodulin (CaM-dependent protein kinase II (CaMKII, a multifunctional serine (Ser/threonine (Thr protein kinase, regulates diverse activities related to Ca2+-mediated neuronal plasticity in the brain, including synaptic activity and gene expression. Among its regulators, protein phosphatase-1 (PP1, a Ser/Thr phosphatase, appears to be critical in controlling CaMKII-dependent neuronal signaling. In postsynaptic densities (PSDs, CaMKII is required for hippocampal long-term potentiation (LTP, a cellular process correlated with learning and memory. In response to Ca2+ elevation during hippocampal LTP induction, CaMKIIα, an isoform that translocates from the cytosol to PSDs, is activated through autophosphorylation at Thr286, generating autonomous kinase activity and a prolonged Ca2+/CaM-bound state. Moreover, PP1 inhibition enhances Thr286 autophosphorylation of CaMKIIα during LTP induction. By contrast, CaMKII nuclear import is regulated by Ser332 phosphorylation state. CaMKIIδ3, a nuclear isoform, is dephosphorylated at Ser332 by PP1, promoting its nuclear translocation, where it regulates transcription. In this review, we summarize physio-pathological roles of CaMKII/PP1 signaling in neurons. CaMKII and PP1 crosstalk and regulation of gene expression is important for neuronal plasticity as well as survival and/or differentiation.

  4. Hippocampal area CA2: an emerging modulatory gateway in the hippocampal circuit.

    Science.gov (United States)

    Benoy, Amrita; Dasgupta, Ananya; Sajikumar, Sreedharan

    2018-04-01

    The hippocampus is a critical brain region for the formation of declarative memories. While social memory had long been attributed to be a function of the hippocampus, it is only of late that the area CA2 of the hippocampus was demarcated as essential for social memory formation. In addition to this distinct role, CA2 possesses unique molecular, structural and physiological characteristics compared to the other CA regions-CA1 and CA3, and the dentate gyrus (DG). CA2 pyramidal neurons are positioned at a location between CA1 and CA3, receiving inputs from CA3 and DG, in addition to forming a powerful disynaptic circuit with direct input from the entorhinal cortical layer II neurons. CA2 also receives direct inputs from the hypothalamic regions and displays a unique expression pattern for receptors for neuromodulators. The location, inputs, and molecular signatures of the area CA2 point to the possibility that CA2 serves as a modulatory gateway that processes information from the entorhinal cortex and CA3, before relaying them onto CA1, the major output of the hippocampus. This review discusses recent findings regarding plasticity and neuromodulation in the CA2 region of the hippocampus, and how this may have the potential to influence plasticity in connecting circuits, and thereby memory and behaviour.

  5. Tumor marker CA 15-3 in breast cancer patients.

    Science.gov (United States)

    Fejzić, Hanifa; Mujagić, Svjetlana; Azabagić, Sanida; Burina, Mensura

    2015-01-01

    The aim of this study was to determine whether there is a correlation between the serum concentration of the tumor marker CA 15-3 and breast cancer, which has not been proven by the existence of regional and distant metastases, and breast cancer with the presence of regional and distant metastases. The study was a retrospective-prospective study, and was conducted on 100 women aged 40-70 years of age in the period of January 2007 until June 2011, in whom, after surgery, breast cancer was histologically verified, where before the surgery serum tumor marker CA 15-3 levels were established. The serum tumor marker CA 15-3 concentrations are determined in all patients after radiological diagnosis of suspected breast cancer (radiological findings concluded as BI RADS 4 and 5). The study excluded patients with liver cirrhosis, liver cancer and lung cancer. The study group consisted of patients with metastatic breast cancer, and the control group of patients with breast cancer comprised those shown to be without verified metastatic disease. To calculate the correlation, Spearman's correlation coefficient was used. A difference in p values of less than 0.05 (ptumor marker CA 15-3 was elevated in all patients with proven remote or clubbing metastasis in 35.5% of patients with metastasis spreading to regional lymph nodes. There is a significant correlation between serum concentrations of the tumor marker CA 15-3 and the presence of metastasis, and serum concentrations of tumor markers and the dissemination of the underlying disease. Copyright © 2015 by Academy of Sciences and Arts of Bosnia and Herzegovina.

  6. Search for the 3-phonon state of 40Ca

    International Nuclear Information System (INIS)

    Fallot, M.

    2002-09-01

    We study collective vibrational states of the nucleus: giant resonances and multiphonon states. It has been shown that multiphonon states, which are built with several superimposed giant resonances, can be excited in inelastic heavy ion scattering near the grazing angle. No three photon states have been observed until now. An experiment has been performed at GANIL, aiming at the observation of the 3-phonon state built with the giant quadrupole resonance (GQR) in 40 Ca, with the reaction 40 Ca + 40 Ca at 50 A.Me.V. The ejectile was identified in the SPEG spectrometer. Light charged particles were detected in 240 CsI scintillators of the INDRA 4π array. The analysis confirms the previous results about the GQR and the 2-phonon state in 40 Ca. For the first time, we have measured an important direct decay branch of the GQR by alpha particles. Applying the so-called 'missing energy method' to events containing three protons measured in coincidence with the ejectile, we observe a direct decay branch revealing the presence of a 3-phonon state in the excitation energy region expected for the triple GQR. Dynamical processes are also studied in the inelastic channel, emphasizing a recently discovered mechanism named towing-mode. We observe for the first time the towing-mode of alpha particles. The energies of multiphonon states in 40 Ca and 208 Pb have been computed microscopically including some anharmonicities via boson mapping methods. The basis of the calculation has been extended to the 3-phonon states. Our results show large anharmonicities (several MeV), due to the coupling of 3-phonon states to 2-phonon states. The extension of the basis to 4-phonon states has been performed for the first time. The inclusion of the 4 phonon states in the calculation did not affect the previous observations concerning the 2-phonon states. Preliminary results on the anharmonicities of the 3-phonon states are presented. (author)

  7. Effect of Ca and CaO on the microstructure and hot compressive deformation behavior of Mg–9.5Zn–2.0Y alloy

    International Nuclear Information System (INIS)

    Kwak, T.Y.; Lim, H.K.; Kim, W.J.

    2015-01-01

    In this study, the effect of adding 0.3 wt% Ca to a Mg–9.5Zn–2.0Y alloy with icosahedral (I) phase (Mg 3 Zn 6 Y) was examined. The Ca alloying was done by two different routes, either through a master alloy produced with Mg and CaO (which is convenient from the points of view of safety and cost) or by direct addition of powdered Ca to the molten alloy. The small addition of Ca (CaO) effectively increased the ignition temperature of the alloys (by about 90 K), which is promising for fire suppression and safe handling with the molten alloys, but it led to the formation of Ca 2 Mg 5 Zn 13 phase at grain boundaries or interdendritic interfaces, causing partial melting and intergranular cracking during compressive deformation near ∼615 K. As a result, the upper limit of hot workability temperature decreased to 598 K, which is lower than that of the Mg–9.5Zn–2.0Y alloy by 125 K. The cast Mg–9.5Zn–2.0Y–0.3Ca alloys prepared using the two different routes exhibited high similarity in ignition temperature, chemical composition, microstructure, hot compressive behaviors and processing maps, indicating that the use of CaO is as effective as the use of Ca in producing the same quality of Ca containing Mg alloys. The flow stresses during hot compressive deformation and the activation energy for plastic flow remained unaffected by the Ca (CaO) alloying, but decreased the strain rate sensitivity at high strain rates over 10 −3 s −1 due to the initiation of either power-law breakdown or partial melting by adiabatic heating. Because of this, the Ca containing alloy lost hot workability at high strain rates by comparison to the Ca-free alloy.

  8. Sodium-calcium exchanger and R-type Ca(2+) channels mediate spontaneous [Ca(2+)]i oscillations in magnocellular neurones of the rat supraoptic nucleus.

    Science.gov (United States)

    Kortus, Stepan; Srinivasan, Chinnapaiyan; Forostyak, Oksana; Zapotocky, Martin; Ueta, Yoichi; Sykova, Eva; Chvatal, Alexandr; Verkhratsky, Alexei; Dayanithi, Govindan

    2016-06-01

    Isolated supraoptic neurones generate spontaneous [Ca(2+)]i oscillations in isolated conditions. Here we report in depth analysis of the contribution of plasmalemmal ion channels (Ca(2+), Na(+)), Na(+)/Ca(2+) exchanger (NCX), intracellular Ca(2+) release channels (InsP3Rs and RyRs), Ca(2+) storage organelles, plasma membrane Ca(2+) pump and intracellular signal transduction cascades into spontaneous Ca(2+) activity. While removal of extracellular Ca(2+) or incubation with non-specific voltage-gated Ca(2+) channel (VGCC) blocker Cd(2+) suppressed the oscillations, neither Ni(2+) nor TTA-P2, the T-type VGCC blockers, had an effect. Inhibitors of VGCC nicardipine, ω-conotoxin GVIA, ω-conotoxin MVIIC, ω-agatoxin IVA (for L-, N-, P and P/Q-type channels, respectively) did not affect [Ca(2+)]i oscillations. In contrast, a specific R-type VGCC blocker SNX-482 attenuated [Ca(2+)]i oscillations. Incubation with TTX had no effect, whereas removal of the extracellular Na(+) or application of an inhibitor of the reverse operation mode of Na(+)/Ca(2+) exchanger KB-R7943 blocked the oscillations. The mitochondrial uncoupler CCCP irreversibly blocked spontaneous [Ca(2+)]i activity. Exposure of neurones to Ca(2+) mobilisers (thapsigargin, cyclopiazonic acid, caffeine and ryanodine); 4-aminopyridine (A-type K(+) current blocker); phospholipase C and adenylyl cyclase pathways blockers U-73122, Rp-cAMP, SQ-22536 and H-89 had no effect. Oscillations were blocked by GABA, but not by glutamate, apamin or dynorphin. In conclusion, spontaneous oscillations in magnocellular neurones are mediated by a concerted action of R-type Ca(2+) channels and the NCX fluctuating between forward and reverse modes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. CA-125, but not galectin-3, complements CA 19-9 for discriminating ductal adenocarcinoma versus non-malignant pancreatic diseases.

    Science.gov (United States)

    Coppin, Lucie; Benomar, Kanza; Corfiotti, François; Cattan, Stéphane; Renaud, Florence; Lapere, Camille; Leteurtre, Emmanuelle; Vantyghem, Marie-Christine; Truant, Stéphanie; Pigny, Pascal

    2016-01-01

    CA 19-9 is the gold standard biomarker of pancreatic adenocarcinoma despite several weaknesses in particular a high rate of false positives or negatives. CA-125 corresponding to MUC16 and galectin-3, a lectin able to interact with mucin-associated carbohydrates, are tumor-associated proteins. We investigated whether combined measurement of CA 19-9, galectin-3 and CA-125 may help to better discriminate pancreatic adenocarcinoma versus non-malignant pancreatic diseases. We evaluated by immunohistochemistry the expression of MUC4, MUC16 (CA-125) and galectin-3 in 31 pancreatic adenocarcinomas. We measured CA 19-9, CA-125 and Gal-3 in the serum from patients with pancreatic benign diseases (n = 58) or adenocarcinoma (n = 44). Clinical performance of the 3 biomarkers for cancer diagnosis and prognosis was analyzed. By immunohistochemistry, MUC16 and Gal-3 were expressed in 74% and 84% of adenocarcinomas versus 0% and 3.2% in peri-tumoral regions, respectively. At the serum level, CA 19-9 and CA125 were significantly higher in patients with pancreatic adenocarcinoma whereas Gal-3 levels did not differ. The performance of CA 19-9 for cancer detection was higher than those of CA-125 or Gal-3 by ROC analysis. However, CA-125 offers the highest specificity for malignancy (81%) because of an absence of false positives among type 2 diabetic patients. Cancer deaths assessed 6 or 12 months after diagnosis varied according to the initial CA-125 level (p CA 19-9 alone exhibits the best performance but measuring CA-125 provides complementary information in terms of diagnosis and prognosis. Copyright © 2015 IAP and EPC. Published by Elsevier India Pvt Ltd. All rights reserved.

  10. Mexican data indicating ca.700 Ma breakup of Rodinia and ca.550 Ma separation of Avalonia: analogous to events in western Laurentia

    Science.gov (United States)

    Keppie, J. D.; Nance, R. D.; Miller, B. V.; Dostal, J.

    2004-05-01

    The supercontinent, Rodinia, appears to have been amalgamated by ca.1 Ga, however, its breakup in Laurentia appears to have occurred in two stages. Current hypotheses suggest that East Gondwana or Siberia separated from western Laurentia at ca.700 Ma followed by separation of (?) South China at ca.550 Ma producing two superposed passive margin sequences. Although prevailing wisdom suggests that the birth of Iapetus between North and South America occurred at ca.550 Ma, a similar 2-stage process is evident in both eastern Laurentia and Mexico. At ca.1 Ga, Mexico appears to have been located in or close to the North-South America suture and so provides crucial data. Geochronological data indicate that cooling following ca.1 Ga granulite facies orogenesis in Mexico followed two different paths. In southern Mexico the rocks initially cooled through ca.450° C at a rate of ca.8° C/my between 978 Ma and 945 Ma related to flat-slab subduction, followed by a cooling rate of ca.2° C/my through ca.150° C. In northern Mexico the rocks cooled at a steady rate of ca.1.8° C/my through ca.300° C and are cut by plume-related mafic dykes. Extrapolating these cooling paths to the surface indicates that southern Mexico reached the surface between 710 and 760 Ma, whereas northern Mexico reached the surface by 550 Ma. This may be partly explained by different depths of exhumation: 30 versus 37 km for southern and northern Mexico, respectively. On the other hand, the oldest rocks resting on the ca.1 Ga basement are Tremadocian (ca.490-480 Ma) in southern Mexico and Middle Silurian (ca.430-425 Ma) in northern Mexico. Thus it would appear that Mexico records two breakup stages: (1) at ca.700 Ma possibly related to the breakup of Rodinia; (2) at ca.550 Ma possibly related to the transcurrent separation of Avalonia followed by thermal equilibration at ca.500 Ma leading to subsidence and development of a passive margin. These data suggest that the breakup of Rodinia occurred at ca.700

  11. Histamine H1-receptor-mediated increase in the Ca2+ transient without a change in the Ca2+ current in electrically stimulated guinea-pig atrial myocytes

    OpenAIRE

    Yoshimoto, Kimihiro; Hattori, Yuichi; Houzen, Hideki; Kanno, Morio; Yasuda, Keishu

    1998-01-01

    The effects of histamine on the intracellular Ca2+ concentration ([Ca2+]i), action potential and membrane currents were assessed in single atrial myocytes prepared from guinea-pigs.Histamine caused a concentration-dependent increase in the [Ca2+]i transient in indo1/AM loaded myocytes when stimulated electrically at 0.5 Hz. However, the maximum increase in [Ca2+]i transient produced by histamine was less than 50% of that elicited by isoprenaline. The histamine-induced increase in [Ca2+]i tran...

  12. Forisome dispersion in Vicia faba is triggered by Ca2+ hotspots created by concerted action of diverse Ca2+ channels in sieve elements

    Science.gov (United States)

    Hafke, Jens B; Furch, Alexandra CU; Fricker, Mark D

    2009-01-01

    Remote-controlled Ca2+ influx, elicited by electropotential waves, triggers local signaling cascades in sieve elements and companion cells along the phloem of Vicia faba plants. The stimulus strength seems to be communicated by the rate and duration of Ca2+ influx into sieve elements (SEs). The cooperative recruitment of Ca2+ channels results in a graded response of forisome culminating in full sieve-tube occlusion. Several lines of evidence are integrated into a model that links the mode and strength of the electropotential waves (EPWs) with forisome dispersion, mediated by transiently enhanced levels of local Ca2+ release dependent on both plasma membrane and ER Ca2+ channels. PMID:19826217

  13. CaMELS: In silico prediction of calmodulin binding proteins and their binding sites.

    Science.gov (United States)

    Abbasi, Wajid Arshad; Asif, Amina; Andleeb, Saiqa; Minhas, Fayyaz Ul Amir Afsar

    2017-09-01

    Due to Ca 2+ -dependent binding and the sequence diversity of Calmodulin (CaM) binding proteins, identifying CaM interactions and binding sites in the wet-lab is tedious and costly. Therefore, computational methods for this purpose are crucial to the design of such wet-lab experiments. We present an algorithm suite called CaMELS (CalModulin intEraction Learning System) for predicting proteins that interact with CaM as well as their binding sites using sequence information alone. CaMELS offers state of the art accuracy for both CaM interaction and binding site prediction and can aid biologists in studying CaM binding proteins. For CaM interaction prediction, CaMELS uses protein sequence features coupled with a large-margin classifier. CaMELS models the binding site prediction problem using multiple instance machine learning with a custom optimization algorithm which allows more effective learning over imprecisely annotated CaM-binding sites during training. CaMELS has been extensively benchmarked using a variety of data sets, mutagenic studies, proteome-wide Gene Ontology enrichment analyses and protein structures. Our experiments indicate that CaMELS outperforms simple motif-based search and other existing methods for interaction and binding site prediction. We have also found that the whole sequence of a protein, rather than just its binding site, is important for predicting its interaction with CaM. Using the machine learning model in CaMELS, we have identified important features of protein sequences for CaM interaction prediction as well as characteristic amino acid sub-sequences and their relative position for identifying CaM binding sites. Python code for training and evaluating CaMELS together with a webserver implementation is available at the URL: http://faculty.pieas.edu.pk/fayyaz/software.html#camels. © 2017 Wiley Periodicals, Inc.

  14. Thapsigargin, a tumor promoter, discharges intracellular Ca2+ stores by specific inhibition of the endoplasmic reticulum Ca2(+)-ATPase

    DEFF Research Database (Denmark)

    Thastrup, Ole; Cullen, P J; Drøbak, B K

    1990-01-01

    Thapsigargin, a tumor-promoting sesquiterpene lactone, discharges intracellular Ca2+ in rat hepatocytes, as it does in many vertebrate cell types. It appears to act intracellularly, as incubation of isolated rat liver microsomes with thapsigargin induces a rapid, dose-dependent release of stored ...

  15. Dynamic Ca2+ imaging with a simplified lattice light-sheet microscope: A sideways view of subcellular Ca2+ puffs.

    Science.gov (United States)

    Ellefsen, Kyle L; Parker, Ian

    2018-05-01

    We describe the construction of a simplified, inexpensive lattice light-sheet microscope, and illustrate its use for imaging subcellular Ca 2+ puffs evoked by photoreleased i-IP 3 in cultured SH-SY5Y neuroblastoma cells loaded with the Ca 2+ probe Cal520. The microscope provides sub-micron spatial resolution and enables recording of local Ca 2+ transients in single-slice mode with a signal-to-noise ratio and temporal resolution (2ms) at least as good as confocal or total internal reflection microscopy. Signals arising from openings of individual IP 3 R channels are clearly resolved, as are stepwise changes in fluorescence reflecting openings and closings of individual channels during puffs. Moreover, by stepping the specimen through the light-sheet, the entire volume of a cell can be scanned within a few hundred ms. The ability to directly visualize a sideways (axial) section through cells directly reveals that IP 3 -evoked Ca 2+ puffs originate at sites in very close (≤a few hundred nm) to the plasma membrane, suggesting they play a specific role in signaling to the membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Application of 17% EDTA Enhances Diffusion of (45)Ca-labeled OH(-) and Ca(2+) in Primary Tooth Root Canal.

    Science.gov (United States)

    Ximenes, Marcos; Cavalcanti Taguchi, Carolina Mayumi; Triches, Thaisa Cezaria; Sartori, Neimar; Pereira Dias, Luis Alberto; de Araujo, Elaine Bortoleti; Cardoso, Mariane

    2016-01-01

    Proper cleaning of the root canal is key to the success of endodontic treatment as it allows more effective diffusion of medication throughout the dentinal tubules. The aim of this in vitro study was to investigate the efficacy of 17% ethylenediaminetetraacetic acid (EDTA) in enhancing diffusion of hydroxyl (OH(-)) and calcium ions (Ca(2+)) throughout the root canal in primary teeth. The canals of 25 primary tooth roots were cleaned with endodontic files and 1% sodium hypochlorite. Three groups (G) were then established: GI, in which final irrigation was performed with 1% sodium hypochlorite; GII, in which 17% EDTA was used; and GIII, in which no irrigation was performed. The roots canals in GI and GII were filled with a calcium hydroxide-based paste labeled with the radioisotope calcium-45. Diffusion of OH(-) was detected with pH strips and Ca(2+) analyzed by measuring radioactivity in counts per min. Group II differed statistically from the other groups in diffusion of OH(-) at 24 hr (p<0.05), but no significant difference among groups was found at the day 7 evaluation; GII also differed statistically from the other groups in diffusion of Ca(2+) at 24 hr (p<0.05). These results suggest that application of 17% EDTA in primary tooth enhances diffusion of OH(-) and Ca(2+).

  17. Inhibition by external Cd2+ of Na/Ca exchange and L-type Ca channel in rabbit ventricular myocytes.

    Science.gov (United States)

    Hobai, I A; Bates, J A; Howarth, F C; Levi, A J

    1997-05-01

    We investigated the effect of external Cd2+ on the Na/Ca exchange and the L-type Ca channel current (ICa,L) in whole cell patch-clamped rabbit ventricular myocytes at 36 degrees C. After the interfering ion channels and the Na/K pump were blocked, the exchange current was measured as the membrane current that was inhibited by 5 mM nickel. External Cd2+ inhibited Na/Ca exchange with a dissociation constant (KD) of 320.6 +/- 12.4 microM and a Hill coefficient of 1.5 +/- 0.09 (n = 13 cells) and ICa,L with a KD of 2.14 +/- 0.15 microM and a Hill coefficient of 0.74 +/- 0.03 (n = 11 cells). We observed some overlap in the Cd2+ concentration that blocked each mechanism. Cd2+ (100-500 microM) is used commonly to block ICa,L completely. However, 100 microM Cd2+ also inhibits 20% of the Na/Ca exchange activity, whereas 500 microM Cd2+ inhibits 60%.

  18. Chelerythrine inhibits the sarco/endoplasmic reticulum Ca(2+)-ATPase and results in cell Ca(2+) imbalance.

    Science.gov (United States)

    Vieira, Saulo Martins; de Oliveira, Vanessa Honorato; Valente, Raphael do Carmo; Moreira, Otacílio da Cruz; Fontes, Carlos Frederico Leite; Mignaco, Julio Alberto

    2015-03-15

    The isoquinoline alkaloid chelerythrine is described as an inhibitor of SERCA. The ATPase inhibition presented two non-competitive components, Ki1=1, 2 μM and Ki2=26 μM. Conversely, chelerythrine presented a dual effect on the p-nitrophenylphosphatase (pNPPase) of SERCA. Ca(2+)-dependent pNPPase was activated up to ∼5 μM chelerythrine with inhibition thereafter. Ca(2+)-independent pNPPase was solely inhibited. The phosphorylation of SERCA with ATP reached half-inhibition with 10 μM chelerythrine and did not parallel the decrease of ATPase activity. In contrast, chelerythrine up to 50 μM increased the phosphorylation by Pi. Cross-linking of SERCA with glutaraldehyde was counteracted by high concentrations of chelerythrine. The controlled tryptic digestion of SERCA shows that the low-affinity binding of chelerythrine evoked an E2-like pattern. Our data indicate a non-competitive inhibition of ATP hydrolysis that favors buildup of the E2-conformers of the enzyme. Chelerythrine as low as 0.5-1.5 μM resulted in an increase of intracellular Ca(2+) on cultured PBMC cells. The inhibition of SERCA and the loss of cell Ca(2+) homeostasis could in part be responsible for some described cytotoxic effects of the alkaloid. Thus, the choice of chelerythrine as a PKC-inhibitor should consider its potential cytotoxicity due to the alkaloid's effects on SERCA. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Migration behaviour of twaite shad Alosa fallax assessed by otolith Sr:Ca and Ba:Ca profiles.

    Science.gov (United States)

    Magath, V; Marohn, L; Fietzke, J; Frische, M; Thiel, R; Dierking, J

    2013-06-01

    Individual migration behaviour during the juvenile and adult life phase of the anadromous twaite shad Alosa fallax in the Elbe estuary was examined using otolith Sr:Ca and Ba:Ca profiles. Between hatching and the end of the first year of life, juveniles showed two migration patterns. Pattern one exhibited a single downstream migration from fresh water to the sea with no return into fresh water. In contrast, pattern two showed a first migration into the sea, then a return into fresh water and, finally, a second downstream migration into marine water. This first report of migration plasticity for A. fallax points to different exposure times to estuarine threats depending on the migration strategy. In adults, high Sr:Ca and low Ba:Ca in the majority of individuals confirmed prior reports of a primarily marine habitat use. Patterns reflecting spawning migrations were rarely observed on otoliths, possibly due to the short duration of visits to fresh water. © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  20. Mg/Ca and Sr/Ca as novel geochemical proxies for understanding sediment transport processes within coral reefs

    Science.gov (United States)

    Gacutan, J.; Vila-Concejo, A.; Nothdurft, L. D.; Fellowes, T. E.; Cathey, H. E.; Opdyke, B. N.; Harris, D. L.; Hamylton, S.; Carvalho, R. C.; Byrne, M.; Webster, J. M.

    2017-10-01

    Sediment transport is a key driver of reef zonation and biodiversity, where an understanding of sediment dynamics gives insights into past reef processes and allows the prediction of geomorphic responses to changing environmental conditions. However, modal conditions within the back-reef seldom promote sediment transport, hence direct observation is inherently difficult. Large benthic foraminifera (LBF) have previously been employed as 'tracers' to infer sediment transport pathways on coral reefs, as their habitat is largely restricted to the algal flat and post-mortem, their calcium carbonate test is susceptible to sediment transport forces into the back-reef. Foraminiferal test abundance and post-depositional test alteration have been used as proxies for sediment transport, although the resolution of these measures becomes limited by low test abundance and the lack of variation within test alteration. Here we propose the novel use of elemental ratios as a proxy for sediment transport. Two species, Baculogypsina sphaerulata and Calcarina capricornia, were analysed using a taphonomic index within One Tree and Lady Musgrave reefs, Great Barrier Reef (Australia). Inductively coupled plasma-atomic emission spectrometry (ICP-AES) was used to determine Mg/Ca and Sr/Ca and these ratios were compared with taphonomic data. Decreases in test Mg/Ca accompany increases in Sr/Ca in specimens from algal-flat to lagoonal samples in both species, mirroring trends indicated by taphonomic values, therefore indicating a relationship with test alteration. To delineate mechanisms driving changes in elemental ratios, back-scattered electron (BSE) images, elemental mapping and in situ quantitative spot analyses by electron microprobe microanalysis (EPMA) using wavelength dispersive X-ray spectrometers (WDS) were performed on un-altered algal flat and heavily abraded tests for both species. EPMA analyses reveal heterogeneity in Mg/Ca between spines and the test wall, implying the loss of

  1. CA125 modified by PLT and NLR improves the predictive accuracy of adenomyosis-derived pelvic dense adhesion

    OpenAIRE

    Jiang, Caixia; Liu, Chao; Guo, Jing; Chen, Li; Luo, Ning; Qu, Xiaoyan; Yang, Weihong; Ren, Qing; Cheng, Zhongping

    2017-01-01

    Abstract To explore the value of serum levels of CA125, platelet count (PLT), neutrophil?lymphocyte ratio (NLR), and modified CA125 markers CA125a and CA125b in predicting pelvic dense adhesion (PDA) associated with adenomyosis, CA125a = lg(CA125???PLT???109), CA125b = lg(CA125???NLR). This retrospective study included 304 patients who underwent surgery for adenomyosis. Correlations of serum levels of CA125, PLT, NLR, and modified CA125 markers with adenomyosis-derived PDA were analyzed by Lo...

  2. Intracellular Ca(2+) overload induced by extracellular Ca(2+) entry plays an important role in acute heart dysfunction by tentacle extract from the jellyfish Cyanea capillata.

    Science.gov (United States)

    Zhang, Lin; He, Qian; Wang, Qianqian; Zhang, Bo; Wang, Beilei; Xu, Feng; Wang, Tao; Xiao, Liang; Zhang, Liming

    2014-09-01

    The exact mechanism of acute heart dysfunction caused by jellyfish venom remains unclear for the moment. In the present study, we examined the problem caused by the tentacle extract (TE) from the jellyfish Cyanea capillata at the levels of whole animal, isolated heart, primarily cultured cardiomyocytes, and intracellular Ca(2+). The heart indexes, including HR, APs, LVPs, and MMLs, were all decreased significantly by TE in both whole animal and Langendorff-perfused isolated heart model. Imbalance of cardiac oxygen supply and demand also took place. In both Ca(2+)-containing and Ca(2+)-free bathing solutions, TE could cause obvious cytoplasmic Ca(2+) overload in NRVMs, but the cytoplasmic Ca(2+) increased faster, Ca(2+) overload peaks arrived earlier, and the morphological changes were more severe under the extracellular Ca(2+)-containing condition. L-type Ca(2+) channel blockers, as well as the inhibitor of ryanodine receptor (ryanodine), could improve the viability of NRVMs. Moreover, diltiazem significantly inhibited the acute heart dysfunction caused by TE in both Langendorff isolated heart model and whole animal. These results suggested that intracellular Ca(2+) overload induced by extracellular Ca(2+) entry plays an important role in acute heart failure by TE from the jellyfish C. capillata. Inhibition of extracellular Ca(2+) influx is a promising antagonistic alternative for heart damage by jellyfish venom.

  3. Diagnostic and prognostic role of preoperative circulating CA 15-3, CA 125, and beta-2 microglobulin in renal cell carcinoma.

    Science.gov (United States)

    Lucarelli, Giuseppe; Ditonno, Pasquale; Bettocchi, Carlo; Vavallo, Antonio; Rutigliano, Monica; Galleggiante, Vanessa; Larocca, Angela Maria Vittoria; Castellano, Giuseppe; Gesualdo, Loreto; Grandaliano, Giuseppe; Selvaggi, Francesco Paolo; Battaglia, Michele

    2014-01-01

    CA 15-3, CA 125 and β-2 microglobulin are three common tumor markers currently used for diagnosis, prognosis, assessment of therapeutic response, and/or to evaluate recurrence in breast and ovarian cancer and malignant lymphoproliferative disorders, respectively. In the present prospective study we assessed the role of these three serum proteins as biomarkers for renal cell carcinoma (RCC), as well as any association between tumor marker levels and clinical-pathological parameters. CA 15-3, CA 125, and β-2 microglobulin were preoperatively measured in 332 patients who underwent nephrectomy for RCC. Estimates of cancer-specific survival (CSS) was calculated according to the Kaplan-Meier method. Multivariate analysis was performed to identify the most significant variables for predicting CSS. Preoperatively, 35.2% (n = 117), 9.6% (n = 32) and 30.4% (n = 101) of the patients had abnormal levels of CA 15-3, CA 125 and β-2 microglobulin, respectively. Statistically significant differences resulted between CA 15-3, CA 125 and β-2 microglobulin values and tumor size, Fuhrman grade, presence of lymph node, and visceral metastases. CSS was significantly decreased for patients with high levels of CA 15-3, CA 125, and β-2 microglobulin (P CA 15-3 were independent adverse prognostic factors for CSS.

  4. Significant elevation in serum CA 125 and CA 19-9 levels with torsion of the hydrosalpinx in a postmenopausal woman.

    Science.gov (United States)

    Kim, Ji Hye; Jung, Hyo Jin; Song, Seung Hun

    2017-07-01

    Isolated torsion of the fallopian tube in postmenopausal women is rare. In this case report, we detail the case of a 53-year-old patient who presented with adenomyosis and a left hydrosalpinx with high levels of CA 125 and CA 19-9. The isolated torsion of the left hydrosalpinx was observed during the operation. The serum levels of CA 125 and CA 19-9 were reduced from 129.62 and 348 to 58.2 and 12.41 U/mL, respectively, after total laparoscopic hysterectomy with salpingectomy. On radiologic evaluation, there were no other factors that may have influenced the increase in serum levels of CA 125 and CA 19-9 in this patient, which were reduced after operation. To the best of our knowledge, this is the first case of association between perioperative changes in CA 19-9 levels and isolated torsion of the fallopian tube.

  5. Chemical UV Filters Mimic the Effect of Progesterone on Ca(2+) Signaling in Human Sperm Cells

    DEFF Research Database (Denmark)

    Rehfeld, A; Dissing, S; Skakkebæk, N E

    2016-01-01

    Progesterone released by cumulus cells surrounding the egg induces a Ca(2+) influx into human sperm cells via the cationic channel of sperm (CatSper) Ca(2+) channel and controls multiple Ca(2+)-dependent responses essential for fertilization. We hypothesized that chemical UV filters may mimic...... the physiological action of progesterone on CatSper, thus affecting Ca(2+) signaling in human sperm cells. We examined 29 UV filters allowed in sunscreens in the United States and/or the European Union for their ability to induce Ca(2+) signals in human sperm by applying measurements of the intracellular free Ca(2......+) signals. Dose-response relations for the UV filters showed that the Ca(2+) signal-inducing effects began in the nanomolar-micromolar range. Single-cell Ca(2+) measurements showed a Ca(2+) signal-inducing effect of the most potent UV filter, 3-BC, at 10 nM. Finally, we demonstrated that the 13 UV filters...

  6. Fabrication and characterisation of nanostructures on CaF2

    International Nuclear Information System (INIS)

    Batzill, M.M.

    1999-04-01

    Novel nanostructure fabrication techniques are described in this dissertation. Furthermore, an unusual two dimensional phase segregation on CaF 2 surfaces after glancing incidence ion beam irradiation is reported. Atomic force microscope (AFM)-tip assisted self-organisation of clusters on anisotropic surfaces is illustrated. This new technique for the fabrication of periodic structures has been demonstrated using silver clusters grown on vicinal CaF 2 (111) surfaces. The scanning action of the tip aligns silver clusters along crystal step edges on the vicinal surface. Nanowire arrays of silver with a uniform periodicity of 20-50 nm and wire widths of 5-7 nm have been achieved over the entire area scanned by the AFM. Calcium remaining on CaF 2 surfaces after electron irradiation induced depletion of the surface of fluorine is found to re-organise itself into island structures. These islands show a shape transition, upon reaching a critical size of ∼ 20 nm in diameter, from a compact to an elongated island shape. Crystal step edge erosion of fluorine allows the formation of long ranging nanowires. These wires have a uniform width of ∼ 15 nm. The observed island shape transition and the width of the wires has been explained by the presence of strain in the islands. This is the first experimental observation confirming a theoretical prediction of the reduction of island width with increasing length for strained islands. A novel technique of ion beam assisted fabrication of periodic nanowire arrays over macroscopic areas is reported. Potential sputtering of CaF 2 surfaces leads to a calcium enriched surface that organised itself in stress domains due to the lattice misfit between calcium and CaF 2 . These stress domains can be oriented by directed ion beam irradiation under glancing angles in parallel stripes with a periodicity of 8-12 nm. A phase segregation on the CaF 2 (111) surface has been observed upon glancing incidence ion beam irradiation under certain

  7. Study of giant multipole resonances in 40Ca

    International Nuclear Information System (INIS)

    Rost, H.

    1979-01-01

    In the present thesis giant resonance states in 40 Ca were studied by scattering of 104 MeV a particles on 40 Ca and by the reactions 39 K(p vector,p') 39 K and 39 K(p,α) 36 Ar. The scattered α-particles were measured at extreme forward angles (THETAsub(L) = 4 0 -16 0 C), because at forward angles the cross sections for the excitation of states with spin 0 and 1 strongly differ from those with higher spin. The aim of this experiment was first of all the study of the giant resonance region in 40 Ca on the contribution to 0 + or 1 - states. Beside the known electric giant quadrupole resonances at Esub(x) approx. equal to 18.5 MeV (25% EWSR) contributions of EO-strength at Esub(x) approx. equal to 21 MeV (6% EWSR) and indications to a (isoscalar) E1-strength at Esub(x) approx. equal to 14 MeV and Esub(x) approx. equal to 16 MeV were found. At the reactions 39 K(p vector,p') 39 K and 39 K(p,α) 36 Ar in the channels (p,p 0 ),(p,p 4 ), (p,αsub(o)), and (p,α 1 ) at incident energies at about 10 MeV (Esub(x)( 40 Ca) approx. equal to 18 MeV) resonant structures were observed. A scattering phase analysis performed for the elastic proton scattering didn't however yield quantitative results about the resonance parameter. An expansion of the cross sections by Legendre polynomials for the remaining reaction channel didn't allow a conclusion about the dominance of a certain L-value. The only indication to the connection of the observed resonant structures with the giant quadrupole resonance in 40 Ca is therefore the energetic position at about Esub(x) approx. equal to 18 MeV. Altogether the observed structures however were not very pronounced, so it can be concluded, that the excitation of the giant quadrupole resonance in 40 Ca by protons via the ground state of 39 K occurs not very strongly. (orig./HSI) [de

  8. Nonlinear dendritic integration in CA1 pyramidal neurons during locomotion.

    Directory of Open Access Journals (Sweden)

    Jeff Magee

    2014-04-01

    Full Text Available Most neuronal circuits receive at least two functionally distinct input types (intrinsic vs. extrinsic; sensory vs. motor; etc. In many pyramidal neuron based microcircuits integration of these two input signals can proceed nonlinearly through the production of active dendritic voltage signals. For example, appropriately timed, perisomatically located, hippocampal (SC and distal dendrite targeting entorhinal (EC3 input produces a distal dendritic Ca2+ plateau potential that drives burst firing output from CA1 pyramidal neurons in vitro. Related signals have been observed in neocortical pyramidal neurons. Until recently it was unknown whether these events occurred in vivo and, if so, during what behavioral states. Here we used simultaneous whole-cell patch and field potential recordings in head-fixed mice running on a linear track treadmill to study this dendritic plateau driven burst firing (plateaus in CA1 neurons. We find that during locomotion dendritic plateau potentials occur within the neuron’s place field with initiation probability peaking near the peak of the firing field. Plateaus produce a large (32±4mV; n=12, slow (duration; 51±7ms somatic depolarization that appears similar to that measured in vitro. Interestingly, plateaus exhibit a dramatic level of theta-phase modulation (~97% that peaks late in the theta cycle (~330°. This late phase peak in plateau potential initiation is near the theta-phase preference of EC3 inputs, suggesting a theta-phase dependent interaction of SC and EC3 inputs. We tested this idea by manipulating the phase of SC inputs by injecting phase adjusted theta frequency currents into CA1 somas. Biasing AP firing earlier in the theta phase decreased plateau probability to ~48% of control whereas biasing AP firing later in phase increased plateau probability 276%. We next directly examined the role of EC3 inputs by inactivating the EC3 axons in CA1 via local light activation of axons expressing

  9. CORRELATION OF 48Ca, 50Ti, AND 138La HETEROGENEITY IN THE ALLENDE REFRACTORY INCLUSIONS

    International Nuclear Information System (INIS)

    Chen, Hsin-Wei; Lee, Typhoon; Lee, Der-Chuen; Chen, Jiang-Chang

    2015-01-01

    Precise determinations of 48 Ca anomalies in Allende calcium–aluminum-rich inclusions (CAIs) are reported in this work. There are endemic positive 48 Ca/ 44 Ca anomalies in all analyzed CAIs after normalization to 42 Ca/ 44 Ca, and it is clearly shown that there is no simple correlation between 48 Ca/ 44 Ca and 50 Ti/ 48 Ti anomalies, in agreement with Jungck et al. Compared to the 48 Ca/ 44 Ca versus 50 Ti/ 48 Ti correlation line defined by differentiated meteorites, reported by Chen et al., the CAIs plot to elevated 50 Ti/ 48 Ti. Assuming the 48 Ca/ 44 Ca anomalies of both CAIs and differentiated meteorites came from the same source, excess 50 Ti anomalies in CAIs can be calculated by subtracting the part associated with 48 Ca/ 44 Ca. These excesses show a linear correlation with 138 La anomalies, a neutrino-process nuclide. According to current stellar nucleosynthetic models, we therefore suggest that the solar system 48 Ca, 50 Ti, and 138 La isotopic variations are made of mixtures between grains condensed from ejecta of neutron-rich accretion-induced SNe Ia and the O/Ne–O/C zone of core-collapse SNe II

  10. Dual mechanism for cAMP-dependent modulation of Ca2+ signalling in articular chondrocytes.

    Science.gov (United States)

    D'Andrea, P; Paschini, V; Vittur, F

    1996-09-01

    The ability of cAMP to modulate the actions of Ca(2+)-mobilizing agonists was studied in single Fura-2-loaded pig articular chondrocytes in primary culture. Forskolin and 8-Br-cAMP increased both the frequency and amplitude of Ca2+ oscillations induced by ATP, and, in unstimulated cells, induced single Ca2+ transients or even Ca2+ oscillations. The cAMP-dependent protein kinase inhibitor H89 totally prevented the effect of cAMP-elevating agents on Ca2+ signalling. Forskolin and 8-Br-cAMP promptly increased the rate of Mn2+ quenching, when administered in the presence of ATP, suggesting a potentiation of receptor-mediated Ca2+ influx. In Ca(2+)-free medium, ATP-induced Ca2+ oscillations decreased and stopped after a few cycles: subsequent ATP additions temporarily resumed the activity, an effect that could be mimicked by forskolin. The same agent induced single Ca2+ transients in 42% of the cell population maintained in Ca(2+)-free medium. Thapsigargin prevented Ca2+ responses to both ATP and forskolin. The results indicate a dual mechanism for cAMP-induced potentiation of Ca2+ signalling in articular chondrocytes: an increase of receptor-mediated Ca2+ influx and a positive modulation of intracellular Ca2+ release.

  11. Crystallization and preliminary X-ray crystallographic analysis of Ca{sup 2+}-independent and Ca{sup 2+}-dependent species of the type II antifreeze protein

    Energy Technology Data Exchange (ETDEWEB)

    Nishimiya, Yoshiyuki; Kondo, Hidemasa [Functional Protein Research Group, Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira, Sapporo 062-8517 (Japan); Yasui, Masanori [Functional Protein Research Group, Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira, Sapporo 062-8517 (Japan); Division of Biological Sciences, Graduate School of Science, Hokkaido University, N8W5, Kita, Sapporo 060-0808 (Japan); Sugimoto, Hiroshi [Biometal Science Laboratory, Riken SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Noro, Natsuko; Sato, Ryoko [Functional Protein Research Group, Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira, Sapporo 062-8517 (Japan); Suzuki, Mamoru [Insititute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Miura, Ai [Functional Protein Research Group, Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira, Sapporo 062-8517 (Japan); Tsuda, Sakae, E-mail: s.tsuda@aist.go.jp [Functional Protein Research Group, Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira, Sapporo 062-8517 (Japan); Division of Biological Sciences, Graduate School of Science, Hokkaido University, N8W5, Kita, Sapporo 060-0808 (Japan)

    2006-06-01

    Crystallization and X-ray data analyses were successful for both Ca{sup 2+}-independent and Ca{sup 2+}-dependent species of the type II antifreeze protein. The resolution of the crystal was 1.35 Å for the Ca{sup 2+}-independent species, and was 1.25 and 1.06 Å for the Ca{sup 2+}-dependent species in the Ca{sup 2+}-free and -bound states, respectively. Ca{sup 2+}-independent and Ca{sup 2+}-dependent species of the type II antifreeze protein (AFP) were both crystallized using the hanging-drop vapour-diffusion method. It appeared that the crystal of the Ca{sup 2+}-independent species from Brachyosis rostratus belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 43.3, b = 48.4, c = 59.7 Å, and diffraction data were collected to 1.34 Å resolution. For the Ca{sup 2+}-dependent type II AFP species from Hypomesus nipponensis, crystallization was carried out for its Ca{sup 2+}-free and Ca{sup 2+}-bound states. 1.25 Å resolution data were collected from the crystal in the Ca{sup 2+}-free state, which exhibited P3{sub 1}21 (or P3{sub 2}21) symmetry, with unit-cell parameters a = b = 66.0, c = 50.3 Å. Data collection could be extended to 1.06 Å resolution for the crystal in the Ca{sup 2+} -bound state, which appeared to be isomorphous to the crystal in the Ca{sup 2+}-free state (unit-cell parameters a = b = 66.0, c = 49.8 Å). These data will allow us to determine the high-resolution structures of the two species of type II AFP.

  12. Cross talk between β subunits, intracellular Ca2+ signaling, and SNAREs in the modulation of CaV 2.1 channel steady-state inactivation.

    Science.gov (United States)

    Serra, Selma Angèlica; Gené, Gemma G; Elorza-Vidal, Xabier; Fernández-Fernández, José M

    2018-01-01

    Modulation of Ca V 2.1 channel activity plays a key role in interneuronal communication and synaptic plasticity. SNAREs interact with a specific synprint site at the second intracellular loop (LII-III) of the Ca V 2.1 pore-forming α 1A subunit to optimize neurotransmitter release from presynaptic terminals by allowing secretory vesicles docking near the Ca 2+ entry pathway, and by modulating the voltage dependence of channel steady-state inactivation. Ca 2+ influx through Ca V 2.1 also promotes channel inactivation. This process seems to involve Ca 2+ -calmodulin interaction with two adjacent sites in the α 1A carboxyl tail (C-tail) (the IQ-like motif and the Calmodulin-Binding Domain (CBD) site), and contributes to long-term potentiation and spatial learning and memory. Besides, binding of regulatory β subunits to the α interaction domain (AID) at the first intracellular loop (LI-II) of α 1A determines the degree of channel inactivation by both voltage and Ca 2+ . Here, we explore the cross talk between β subunits, Ca 2+ , and syntaxin-1A-modulated Ca V 2.1 inactivation, highlighting the α 1A domains involved in such process. β 3 -containing Ca V 2.1 channels show syntaxin-1A-modulated but no Ca 2+ -dependent steady-state inactivation. Conversely, β 2a -containing Ca V 2.1 channels show Ca 2+ -dependent but not syntaxin-1A-modulated steady-state inactivation. A LI-II deletion confers Ca 2+ -dependent inactivation and prevents modulation by syntaxin-1A in β 3 -containing Ca V 2.1 channels. Mutation of the IQ-like motif, unlike CBD deletion, abolishes Ca 2+ -dependent inactivation and confers modulation by syntaxin-1A in β 2a -containing Ca V 2.1 channels. Altogether, these results suggest that LI-II structural modifications determine the regulation of Ca V 2.1 steady-state inactivation either by Ca 2+ or by SNAREs but not by both. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and

  13. Modulation of intracellular calcium waves and triggered activities by mitochondrial ca flux in mouse cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Zhenghang Zhao

    Full Text Available Recent studies have suggested that mitochondria may play important roles in the Ca(2+ homeostasis of cardiac myocytes. However, it is still unclear if mitochondrial Ca(2+ flux can regulate the generation of Ca(2+ waves (CaWs and triggered activities in cardiac myocytes. In the present study, intracellular/cytosolic Ca(2+ (Cai (2+ was imaged in Fluo-4-AM loaded mouse ventricular myocytes. Spontaneous sarcoplasmic reticulum (SR Ca(2+ release and CaWs were induced in the presence of high (4 mM external Ca(2+ (Cao (2+. The protonophore carbonyl cyanide p-(trifluoromethoxyphenylhydrazone (FCCP reversibly raised basal Cai (2+ levels even after depletion of SR Ca(2+ in the absence of Cao (2+ , suggesting Ca(2+ release from mitochondria. FCCP at 0.01 - 0.1 µM partially depolarized the mitochondrial membrane potential (Δψ m and increased the frequency and amplitude of CaWs in a dose-dependent manner. Simultaneous recording of cell membrane potentials showed the augmentation of delayed afterdepolarization amplitudes and frequencies, and induction of triggered action potentials. The effect of FCCP on CaWs was mimicked by antimycin A (an electron transport chain inhibitor disrupting Δψ m or Ru360 (a mitochondrial Ca(2+ uniporter inhibitor, but not by oligomycin (an ATP synthase inhibitor or iodoacetic acid (a glycolytic inhibitor, excluding the contribution of intracellular ATP levels. The effects of FCCP on CaWs were counteracted by the mitochondrial permeability transition pore blocker cyclosporine A, or the mitochondrial Ca(2+ uniporter activator kaempferol. Our results suggest that mitochondrial Ca(2+ release and uptake exquisitely control the local Ca(2+ level in the micro-domain near SR ryanodine receptors and play an important role in regulation of intracellular CaWs and arrhythmogenesis.

  14. Theoretical study on the reaction mechanism of CH4 with CaO

    International Nuclear Information System (INIS)

    Yang Huawqing; Hu Changwei; Qin Song

    2006-01-01

    The reaction pathways and energetics for the reaction of methane with CaO are discussed on the singlet spin state potential energy surface at the B3LYP/6-311+G(2df,2p) and QCISD/6-311++G(3df,3pd)//B3LYP/6-311+G(2df,2p) levels of theory. The reaction of methane with CaO is proposed to proceed in the following reaction pathways: CaO + CH 4 → CaOCH 4 → [TS] → CaOH + CH 3 , CaO + CH 4 → OCaCH 4 → [TS] → HOCaCH 3 → CaOH + CH 3 or [TS] → CaCH 3 OH → Ca + CH 3 OH, and OCaCH 4 → [TS] → HCaOCH 3 → CaOCH 3 + H or [TS] → CaCH 3 OH → Ca + CH 3 OH. The gas-phase methane-methanol conversion by CaO is suggested to proceed via two kinds of important reaction intermediates, HOCaCH 3 and HCaOCH 3 , and the reaction pathway via the hydroxy intermediate (HOCaCH 3 ) is energetically more favorable than the other one via the methoxy intermediate (HCaOCH 3 ). The hydroxy intermediate HOCaCH 3 is predicted to be the energetically most preferred configuration in the reaction of CaO + CH 4 . Meanwhile, these three product channels (CaOH + CH 3 , CaOCH 3 + H and Ca + CH 3 OH) are expected to compete with each other, and the formation of methyl radical is the most preferable pathway energetically. On the other hand, the intermediates HCaOCH 3 and HOCaCH 3 are predicted to be the energetically preferred configuration in the reaction of Ca + CH 3 OH, which is precisely the reverse reaction of methane hydroxylation

  15. Bose-Einstein condensation of alkaline earth atoms: ;{40}Ca.

    Science.gov (United States)

    Kraft, Sebastian; Vogt, Felix; Appel, Oliver; Riehle, Fritz; Sterr, Uwe

    2009-09-25

    We have achieved Bose-Einstein condensation of ;{40}Ca, the first for an alkaline earth element. The influence of elastic and inelastic collisions associated with the large ground-state s-wave scattering length of ;{40}Ca was measured. From these findings, an optimized loading and cooling scheme was developed that allowed us to condense about 2 x 10;{4} atoms after laser cooling in a two-stage magneto-optical trap and subsequent forced evaporation in a crossed dipole trap within less than 3 s. The condensation of an alkaline earth element opens novel opportunities for precision measurements on the narrow intercombination lines as well as investigations of molecular states at the ;{1}S-;{3}P asymptotes.

  16. Thermoluminescent dosemeters of CaSO4: Dy + Teflon

    International Nuclear Information System (INIS)

    Campos, L.L.

    1989-01-01

    The development of a pellet dosemeter of CaSO 4 : Dy + Teflon at the Dosimetric Materials Production Laboratory - IPEN/Brazilian CNEN-SP is presented. The pellets were produced by cold pressing and sintering a mixture of CaSO 4 : Dy and Teflon powders. The pellet characteristics from the point of view of dosimetry. A filter combination providing an energy independent response from 20 KeV to 1,25 MeV was obtained. The dosemeter consists of three pellets sealed between two thin plastic sheets and placed under plastic and lead filters. The combination of these three filters allows to determine the energy of an unknown source. (author) [pt

  17. [PIK3CA-related overgrowth syndrome (PROS)].

    Science.gov (United States)

    Venot, Quitterie; Canaud, Guillaume

    2017-04-01

    This review presents an overview of a recently characterized spectrum of overgrowth syndrome: phosphoinositide-3 kinase (PI3K)-related overgrowth spectrum (PROS). This spectrum encompasses overgrowth syndromes associated with somatic mosaic activating PIK3CA mutations such as megalencephaly-capillary malformation (MCAP) syndrome, dysplatic megalencephaly (DMEG), congenital lipomatous asymmetric overgrowth of the trunk, lymphatic, capillary, venous, and combined-type vascular malformations, epidermal nevi, skeletal and spinal anomalies (CLOVES) syndrome, hemihyperplasia-multiple lipomatosis (HHML), fibroadipose overgrowth and Klippel-Trenaunay syndrome. Mosaic gain of function mutation in PIK3CA gene leads to abnormal AKT-mTOR pathway activation and is responsible of the clinical manifestations. Here, we summarize the current knowledge on this disorder. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

  18. SNL/CA Facilities Management Design Standards Manual

    Energy Technology Data Exchange (ETDEWEB)

    Rabb, David [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Clark, Eva [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2014-12-01

    At Sandia National Laboratories in California (SNL/CA), the design, construction, operation, and maintenance of facilities is guided by industry standards, a graded approach, and the systematic analysis of life cycle benefits received for costs incurred. The design of the physical plant must ensure that the facilities are "fit for use," and provide conditions that effectively, efficiently, and safely support current and future mission needs. In addition, SNL/CA applies sustainable design principles, using an integrated whole-building design approach, from site planning to facility design, construction, and operation to ensure building resource efficiency and the health and productivity of occupants. The safety and health of the workforce and the public, any possible effects on the environment, and compliance with building codes take precedence over project issues, such as performance, cost, and schedule.

  19. Inhibiting the Ca2+ Influx Induced by Human CSF

    Directory of Open Access Journals (Sweden)

    Anna Drews

    2017-12-01

    Full Text Available One potential therapeutic strategy for Alzheimer’s disease (AD is to use antibodies that bind to small soluble protein aggregates to reduce their toxic effects. However, these therapies are rarely tested in human CSF before clinical trials because of the lack of sensitive methods that enable the measurement of aggregate-induced toxicity at low concentrations. We have developed highly sensitive single vesicle and single-cell-based assays that detect the Ca2+ influx caused by the CSF of individuals affected with AD and healthy controls, and we have found comparable effects for both types of samples. We also show that an extracellular chaperone clusterin; a nanobody specific to the amyloid-β peptide (Aβ; and bapineuzumab, a humanized monoclonal antibody raised against Aβ, could all reduce the Ca2+ influx caused by synthetic Aβ oligomers but are less effective in CSF. These assays could be used to characterize potential therapeutic agents in CSF before clinical trials.

  20. The effect of 45Ca on mouse hematology

    International Nuclear Information System (INIS)

    Gupta, N.K.; Kumar, A.

    1982-01-01

    Male Swiss albino mice were administered intraperitoneally with 19 and 37 kBq/g body weight of 45 Ca. The animals were autopsied after 1, 3, 5 days and 1 and 2 weeks after the administration of 45 Ca. The animals did not show symptoms of radiation sicknes. Erythrocyte values showed reduction till the 7th day post treatment followed by an increase later. An abortive rise was seen in case of leukocytes at the 3th day post treatment and after that a decrease in their number was observed. Hemoglobin and hematocrit values also showed a decrease followed by an increase like the erythrocyte values. Further a macrocytic anemia was observed. (author)

  1. Rapid efflux of Ca2+ from heart mitochondria in the presence of inorganic pyrophosphate.

    Science.gov (United States)

    Vercesi, A; Lehninger, A L

    1984-01-13

    Inorganic pyrophosphate (PPi) in the intracellular concentration range causes rapid efflux of Ca2+ from rat heart mitochondria oxidizing pyruvate + malate in a low Na+ medium. Half-maximal rates of Ca2+ efflux were given by 20 microM PPi. During and after PPi-stimulated Ca2+ efflux the mitochondria retain their structural integrity and complete respiratory control. Carboxyatractyloside inhibits PPi-stimulated Ca2+ efflux, indicating PPi must enter the matrix in order to promote Ca2+ efflux. Heart mitochondria have a much higher affinity for PPi uptake and PPi-induced Ca2+ efflux than liver mitochondria.

  2. Internal Ca2+ mobilization and secretion in bovine adrenal chromaffin cells

    DEFF Research Database (Denmark)

    Cheek, T R; Thastrup, Ole

    1989-01-01

    Since secretion from intact bovine adrenal chromaffin cells in response to depolarization by nicotine is triggered by a rise in the concentration of intracellular Ca2+ ([Ca2+]i) to about 200-300 nM above basal, it has been assumed that the failure of the inositol 1,4,5-trisphosphate (InsP3...... and the sesquiterpene lactone thapsigargin (TG), which releases internal Ca2+ without concomitant breakdown of inositol lipids or protein kinase C activation, to examine the events which follow depletion of the releasable Ca2+ store in these cells. Monitoring [Ca2+]i using Fura-2 demonstrated that TG released Ca2+ from...

  3. Vibrational Spectroscopy of Laser Cooled CaH

    Science.gov (United States)

    2015-10-28

    collisional processes involving highly excited states of atomic ions such as Ca+ and Mg+ with H2 in stellar atmospheres leads to the broadening of... heavy - ion system to the frequency of the precision of the electron spin [34]. However, comparing the rovibrational spectra of molecules remains the...in this thesis is the trapping and cooling of charged particles. This is facilitated by a Paul RF quadrupole trap that confines the ions in three

  4. Changes in rat hippocampal CA1 synapses following imipramine treatment

    DEFF Research Database (Denmark)

    Chen, Fenghua; Madsen, Torsten M; Wegener, Gregers

    2008-01-01

    Neuronal plasticity in hippocampus is hypothesized to play an important role in both the pathophysiology of depressive disorders and the treatment. In this study, we investigated the consequences of imipramine treatment on neuroplasticity (including neurogenesis, synaptogenesis, and remodelling...... and number of neurons of hippocampal subregions following imipramine treatment were found. However, the number and percentage of CA1 asymmetric spine synapses increased significantly and, conversely, the percentage of asymmetric shaft synapses significantly decreased in the imipramine treated group. Our...

  5. Performance of CaSO4:Dy detectors

    International Nuclear Information System (INIS)

    Setti, M.C.; Silva, G.R.; Pela, C.A.; Bruco, J.L.; Borges, J.C.

    2004-01-01

    CaSO 4 :Dy detectors have been used in personal dosimetry. The MRA company recently entered into the market of these detectors. Searching to assure a product quality level that would satisfy its customs most expectancies, MRA programmed several tests to qualify and quantify these detectors main characteristics, before their definitive insertion in the market. Preliminary tests furnished a value of 29,5 ± 1,2 nC for homogeneity and a maximum dispersion of 3 % for linearity . (author)

  6. Circularly permuted green fluorescent proteins engineered to sense Ca2+

    OpenAIRE

    Nagai, Takeharu; Sawano, Asako; Park, Eun Sun; Miyawaki, Atsushi

    2001-01-01

    To visualize Ca2+-dependent protein–protein interactions in living cells by fluorescence readouts, we used a circularly permuted green fluorescent protein (cpGFP), in which the amino and carboxyl portions had been interchanged and reconnected by a short spacer between the original termini. The cpGFP was fused to calmodulin and its target peptide, M13. The chimeric protein, which we have named “pericam,” was fluorescent and its spectral properties changed reversibly...

  7. Phosphorylation Modulates Ameloblastin Self-assembly and Ca2+ Binding

    Czech Academy of Sciences Publication Activity Database

    Stakkestad, O.; Lyngstadaas, S. P.; Thiede, B.; Vondrášek, Jiří; Skalhegg, B. S.; Reseland, J. E.

    2017-01-01

    Roč. 8, Jul 27 (2017), č. článku 531. ISSN 1664-042X Institutional support: RVO:61388963 Keywords : ameloblastin * phosphorylation * self-assembly * Ca2+-binding * enamel * intrinsically disordered proteins Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 4.134, year: 2016 http://journal.frontiersin.org/article/10.3389/fphys.2017.00531/full

  8. Component geochronology in the polyphase ca. 3920 Ma Acasta Gneiss

    Science.gov (United States)

    Mojzsis, Stephen J.; Cates, Nicole L.; Caro, Guillaume; Trail, Dustin; Abramov, Oleg; Guitreau, Martin; Blichert-Toft, Janne; Hopkins, Michelle D.; Bleeker, Wouter

    2014-01-01

    The oldest compiled U–Pb zircon ages for the Acasta Gneiss Complex in the Northwest Territories of Canada span about 4050–3850 Ma; yet older ca. 4200 Ma xenocrystic U–Pb zircon ages have also been reported for this terrane. The AGC expresses at least 25 km2 of outcrop exposure, but only a small subset of this has been documented in the detail required to investigate a complex history and resolve disputes over emplacement ages. To better understand this history, we combined new ion microprobe235,238U–207,206Pb zircon geochronology with whole-rock and zircon rare earth element compositions ([REE]zirc), Ti-in-zircon thermometry (Tixln) and 147Sm–143Nd geochronology for an individual subdivided ∼60 cm2 slab of Acasta banded gneiss comprising five separate lithologic components. Results were compared to other variably deformed granitoid-gneisses and plagioclase-hornblende rocks from elsewhere in the AGC. We show that different gneissic components carry distinct [Th/U]zirc vs. Tixln and [REE]zirc signatures correlative with different zircon U–Pb age populations and WR compositions, but not with 147Sm–143Nd isotope systematics. Modeled  [REE] from lattice-strain theory reconciles only the ca. 3920 Ma zircons with the oldest component that also preserves strong positive Eu∗ anomalies. Magmas which gave rise to the somewhat older (inherited) ca. 4020 Ma AGC zircon age population formed at ∼IW (iron–wüstite) to ca. 3920 Ma emplacement age for the AGC is contemporaneous with bombardment of the inner solar system. Analytical bombardment simulations show that crustal re-working from the impact epoch potentially affected the precursors to the Acasta gneisses.

  9. En stormandsresidens ved Tissø, ca. 550-1050

    DEFF Research Database (Denmark)

    Bican, Josefine Franck; Holst, Sandie; Albris, Sofie Laurine

    2016-01-01

    Ved Tissø på Vestsjælland er påvist en meget rig plads fra yngre jernalder og vikingetid, som er opkaldt efter søen. Her residerede en magtfuld stormand i store residenskomplekser, og her mødtes mennesker for at handle og praktisere den førkristne religion. I løbet af perioden ca. 550-1050 e...

  10. Ketamine inhibits human sperm function by Ca(2+)-related mechanism.

    Science.gov (United States)

    He, Yuanqiao; Zou, Qianxing; Li, Bingda; Chen, Houyang; Du, Xiaohong; Weng, Shiqi; Luo, Tao; Zeng, Xuhui

    2016-09-09

    Ketamine, a dissociative anesthetic, which was widely used in human and animal medicine, has become a popular recreational drug, as it can induce hallucinatory effects. Ketamine abuse can cause serious damage to many aspects of the organism, mainly reflected in the nervous system and urinary system. It has also been reported that ketamine can impair the male genital system. However, the detailed effect of ketamine on human spermatozoa remains unclear. Thus, we investigated the in vitro effects of ketamine on human sperm functions, to elucidate the underlying mechanism. Human sperm were treated in vitro with different concentrations of ketamine (0, 0.125, 0.25, 0.5, 1 g/L). The results showed that 0.25-1 g/L ketamine inhibited sperm total motility, progressive motility and linear velocity, in a dose-dependent manner. In addition, the sperm's ability to penetrate viscous medium and the progesterone-induced acrosome reaction were significantly inhibited by ketamine. Ketamine did not affect sperm viability, capacitation and spontaneous acrosome reaction. The intracellular calcium concentration ([Ca(2+)]i), which is a central factor in the regulation of human sperm function, was decreased by ketamine (0.125-1 g/L) in a dose-dependent manner. Furthermore, the currents of the sperm-specific Ca(2+) channel, CatSper, which modulates Ca(2+) influx in sperm, were inhibited by ketamine (0.125-1 g/L) in a dose-dependent manner. Our findings suggest that ketamine induces its toxic effects on human sperm functions by reducing sperm [Ca(2+)]i through inhibition of CatSper channel. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Concentration of Ca in blood of amateur runners using NAA

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, L.; Zamboni, C. B.; Metairon, S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN / CNEN - SP) - Centro do Reator de Pesquisas Av. Professor Lineu Prestes, 2242 - 05508-000 Sao Paulo, SP (Brazil); Nunes, L. A. S.; Lourenco, T. F.; Macedo, D. V. [Universidade Estadual de Campinas - UNICAMP - Laboratorio de Bioquimica do Exercicio - LABEX Cidade Universitaria 13083-970 - Campinas, SP Brazil - Caixa-Postal: 6109 (Brazil)

    2013-05-06

    In this study the Ca levels were determined in amateur runners blood at LABEX (Laboratorio de Bioquimica do Exercicio - UNICAMP, Brazil), using Neutron Activation Analyses (NAA) technique. The range established at rest (162 - 410 mgL{sup -1}) when compared with control group (51 - 439 mgL{sup -1}) suggests that there is a dependency of these limits in the function of the adopted physical training.

  12. Compression characteristics and permeability of saturated Gaomiaozi ca-bentonite

    International Nuclear Information System (INIS)

    Sun Wenjing; Sun De'an; Fang Lei

    2012-01-01

    The compression characteristics and permeability of compacted Gaomiaozi Ca-bentonite saturated by the water uptake tests are studied by conducting a series of one-dimension compression tests. The permeability coefficient can be calculated by the Terzaghi's one-dimensional consolidation theory after the consolidation coefficient is obtained by the square root of time method. It is found that the compression curves of compacted specimens saturated by the water uptake tests tend to be consistent in the relatively high stress range. The compression indexes show a linear decrease with increasing dry density and the swelling index is a constant. The permeability coefficient decreases with increasing compression stress, and they show the linear relationship in double logarithmic coordinates. Meanwhile, the permeability coefficient shows a linear decrease with decreasing void ratio, which has no relationship with initial states, stress states and stress paths. The permeability coefficient k of GMZ Ca-bentonite at dry density Pd of 1.75 g/cm 3 can be calculated as 2.0 × 10 -11 cm/s by the linear relationship between Pd and log k. It is closed to the permeability coefficient of GMZ Ca-bentonite with the same dry density published in literature, which testifies that the method calculating the permeability coefficient is feasible from the consolidation coefficient obtained by the consolidation test. (authors)

  13. Broadband set-top box using MAP-CA processor

    Science.gov (United States)

    Bush, John E.; Lee, Woobin; Basoglu, Chris

    2001-12-01

    Advances in broadband access are expected to exert a profound impact in our everyday life. It will be the key to the digital convergence of communication, computer and consumer equipment. A common thread that facilitates this convergence comprises digital media and Internet. To address this market, Equator Technologies, Inc., is developing the Dolphin broadband set-top box reference platform using its MAP-CA Broadband Signal ProcessorT chip. The Dolphin reference platform is a universal media platform for display and presentation of digital contents on end-user entertainment systems. The objective of the Dolphin reference platform is to provide a complete set-top box system based on the MAP-CA processor. It includes all the necessary hardware and software components for the emerging broadcast and the broadband digital media market based on IP protocols. Such reference design requires a broadband Internet access and high-performance digital signal processing. By using the MAP-CA processor, the Dolphin reference platform is completely programmable, allowing various codecs to be implemented in software, such as MPEG-2, MPEG-4, H.263 and proprietary codecs. The software implementation also enables field upgrades to keep pace with evolving technology and industry demands.

  14. Evaluation of clinical value of serum CA19-9

    International Nuclear Information System (INIS)

    Lv Haifeng; Lin Zhiyu; Lu Xiaozhuo; Chen Yini

    2003-01-01

    The article is to study the clinical significance of serum CA19-9 in diagnosing malignant tumor occurred in digestive system and to select cut off values for differentiating diagnosis of a pancreatic neoplasms and pancreatitis. Using chemiluminescence immunoassay, serum CA19-9 level of below subjects were analyzed: control group (n=21); digestive system neoplasm group (n=125, with 7 cases conformed as pancreatic cancer); non-neoplastic disease group (n=387, with 15 cases conformed as pancreatitis secondary to destructive cholangitis). Receiver operating characteristic (ROC) curve was used for analyzing results and selecting cut off values. When cut off value was 18.4 kU/L, sensibility for conforming a digestive system neoplasm was 60.8%, while its related specificity against control group and non-neoplastic disease group was 95. 2% and 68.2%, respectively. Sensibility for diagnosing pancreatic neoplasm was 85.7%, while its related specificity against control group and non-pancreatic origin tumor group was 95.0% and 63.1%, respectively. When 37 kU/L was chosen as cut off value, specificity for differentiating diagnosis of pancreatic neoplasm and pancreatitis secondary to destructive cholangitis rose from 13.3% to 46.7%. Serum CA19-9 could be used as an aid in detecting digestive system neoplastic disease; it is a reliable marker for pancreatic neoplasm. Raising cut off value may help to differentiate pancreatic neoplasm and pancreatitis secondary to destructive cholangitis

  15. Investigation of the RbCa molecule: Experiment and theory

    Science.gov (United States)

    Pototschnig, Johann V.; Krois, Günter; Lackner, Florian; Ernst, Wolfgang E.

    2015-04-01

    We present a thorough theoretical and experimental study of the electronic structure of RbCa. The mixed alkali-alkaline earth molecule RbCa was formed on superfluid helium nanodroplets. Excited states of the molecule in the range of 13 000-23 000 cm-1 were recorded by resonance enhanced multi-photon ionization time-of-flight spectroscopy. The experiment is accompanied by high level ab initio calculations of ground and excited state properties, utilizing a multireference configuration interaction method based on multiconfigurational self consistent field calculations. With this approach the potential energy curves and permanent electric dipole moments of 24 electronic states were calculated. In addition we computed the transition dipole moments for transitions from the ground into excited states. The combination of experiment and theory allowed the assignment of features in the recorded spectrum to the excited 32Σ+, 42Σ+, 32 Π, 52Σ+, 42 Π, 62Σ+, 62 Π, and 72 Π states, where the experiment allowed to benchmark the calculation. This is the first experimental work giving insight into the previously unknown RbCa molecule, which offers great prospects in ultracold molecular physics due to its magnetic and electronic dipole moment in the 2Σ+ ground state.

  16. Mutational profiling reveals PIK3CA mutations in gallbladder carcinoma

    Directory of Open Access Journals (Sweden)

    Bardeesy Nabeel

    2011-02-01

    Full Text Available Abstract Background The genetics of advanced biliary tract cancers (BTC, which encompass intra- and extra-hepatic cholangiocarcinomas as well as gallbladder carcinomas, are heterogeneous and remain to be fully defined. Methods To better characterize mutations in established known oncogenes and tumor suppressor genes we tested a mass spectrometric based platform to interrogate common cancer associated mutations across a panel of 77 formalin fixed paraffin embedded archived BTC cases. Results Mutations among three genes, KRAS, NRAS and PIK3CA were confirmed in this cohort. Activating mutations in PIK3CA were identified exclusively in GBC (4/32, 12.5%. KRAS mutations were identified in 3 (13% intra-hepatic cholangiocarcinomas and 1 (33% perihillar cholangiocarcinoma but were not identified in gallbladder carcinomas and extra-hepatic cholangiocarcinoma. Conclusions The presence of activating mutations in PIK3CA specifically in GBC has clinical implications in both the diagnosis of this cancer type, as well as the potential utility of targeted therapies such as PI3 kinase inhibitors.

  17. Ultrasonic Investigations on Polonides of Ba, Ca, and Pb

    Science.gov (United States)

    Singh, Devraj; Bhalla, Vyoma; Bala, Jyoti; Wadhwa, Shikha

    2017-10-01

    The temperature-dependent mechanical and ultrasonic properties of barium, calcium, and lead polonides (BaPo, CaPo, and PbPo) were investigated in the temperature range 100-300 K. The second- and third-order elastic constants (SOECs and TOECs) were computed using Coulomb and Born-Mayer potential and these in turn have been used to estimate other secondary elastic properties such as strength, anisotropy, microhardness, etc. The theoretical approach followed the prediction that BaPo, CaPo, and PbPo are brittle in nature. PbPo is found to be the hardest amongst the chosen compounds. Further the SOECs and TOECs are applied to determine ultrasonic velocities, Debye temperature, and acoustic coupling constants along , , and orientations at room temperature. Additionally thermal conductivity has been computed using Morelli and Slack's approach along different crystallographic directions at room temperature. Finally ultrasonic attenuation due to phonon-phonon interaction and thermoelastic relaxation mechanisms has been computed for BaPo, CaPo, and PbPo. The behaviour of these compounds is similar to that of semi-metals with thermal relaxation time of the order 10-11 s. The present computation study is reasonably in agreement with the available theoretical data for the similar type of materials.

  18. Ultrasonic investigations on polonides of Ba, Ca, and Pb

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Devraj; Bhalla, Vyoma [Amity School of Engineering and Technology, New Delhi (India). Dept. of Applied Physics; Bala, Jyoti [Amity School of Engineering and Technology, New Delhi (India). Dept. of Applied Physics; Guru Gobind Singh Indraprastha Univ., New Delhi (India). USICT; Wadhwa, Shikha [Amity Univ., Noida (India). Amity Inst. of Nanotechnology

    2017-07-01

    The temperature-dependent mechanical and ultrasonic properties of barium, calcium, and lead polonides (BaPo, CaPo, and PbPo) were investigated in the temperature range 100-300 K. The second- and third-order elastic constants (SOECs and TOECs) were computed using Coulomb and Born-Mayer potential and these in turn have been used to estimate other secondary elastic properties such as strength, anisotropy, microhardness, etc. The theoretical approach followed the prediction that BaPo, CaPo, and PbPo are brittle in nature. PbPo is found to be the hardest amongst the chosen compounds. Further the SOECs and TOECs are applied to determine ultrasonic velocities, Debye temperature, and acoustic coupling constants along left angle 100 right angle, left angle 110 right angle, and left angle 111 right angle orientations at room temperature. Additionally thermal conductivity has been computed using Morelli and Slack's approach along different crystallographic directions at room temperature. Finally ultrasonic attenuation due to phonon-phonon interaction and thermoelastic relaxation mechanisms has been computed for BaPo, CaPo, and PbPo. The behaviour of these compounds is similar to that of semi-metals with thermal relaxation time of the order 10{sup -11} s. The present computation study is reasonably in agreement with the available theoretical data for the similar type of materials.

  19. Optimalisasi Biosorpsi Bekatul Terhadap Kalsium (Ca dengan Menggunakan Metode Batch

    Directory of Open Access Journals (Sweden)

    Subarman Subarman

    2013-01-01

    Full Text Available The study is titled Optimization of biosorption Biomass Against Calcium (Ca by using the method of Batch. Background on this research that, the utilization of biomass as an adsorbent bran on the absorption of calcium metal (Ca and reduce the pollution caused from the bran biomass. This study aims to determine the optimum pH and time as well as processing of biomass with metal biosorption Calcium (Ca. Bran biomass taken directly to rice mills in Kecematan Pallangga Gowa. The method used in  this  study is  the activation process,  the  determination  of  the  optimum  pH,  optimum  timing, method in the determination of biosorption Batch, then the results were analyzed by using Atomic absorption spectrophotometer (AAS.The results obtained from this study is that the pH optimum at pH 9, the optimum contact time to 15 minutes, and the biosorption capacity of 14.1804 mg/L.

  20. Regulation of CaMKII signaling in cardiovascular disease

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    Mariya Yordanova Mollova

    2015-08-01

    Full Text Available Heart failure (HF is a major cause of death in the developed countries. (Murray and Lopez, 1996;Koitabashi and Kass, 2012. Adverse cardiac remodeling that precedes heart muscle dysfunction is characterized by a myriad of molecular changes affecting the cardiomyocyte. Among these, alterations in protein kinase pathways play often an important mediator role since they link upstream pathologic stress signaling with downstream regulatory programs and thus affect both the structural and functional integrity of the heart muscle. In the context of cardiac disease, a profound understanding for the overriding mechanisms that regulate protein kinase activity (protein-protein interactions, post-translational modifications, or targeting via anchoring proteins is crucial for the development of specific and effective pharmacological treatment strategies targeting the failing myocardium.In this review, we focus on several mechanisms of upstream regulation of Ca2+/Calmodulin-dependent kinase II (CaM Kinase II, CaMKII that play a relevant pathophysiological role in the development and progression of cardiovascular disease; precise targeting of these mechanisms might therefore represent novel and promising tools for prevention and treatment of HF.

  1. Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia shell calcite precipitated at constant temperature

    Directory of Open Access Journals (Sweden)

    P. S. Freitas

    2009-07-01

    Full Text Available Small-scale heterogeneity of biogenic carbonate elemental composition can be a significant source of error in the accurate use of element/Ca ratios as geochemical proxies. In this study ion microprobe (SIMS profiles showed significant small-scale variability of Mg/Ca, Sr/Ca and Mn/Ca ratios in new shell calcite of the marine bivalves Pecten maximus and Mytilus edulis that was precipitated during a constant-temperature culturing experiment. Elevated Mg/Ca, Sr/Ca and Mn/Ca ratios were found to be associated with the deposition of elaborate shell features, i.e. a shell surface stria in P. maximus and surface shell disturbance marks in both species, the latter a common occurrence in bivalve shells. In both species the observed small-scale elemental heterogeneity most likely was not controlled by variable transport of ions to the extra-pallial fluid, but by factors such as the influence of shell organic content and/or crystal size and orientation, the latter reflecting conditions at the shell crystal-solution interface. In the mid and innermost regions of the P. maximus shell the lack of significant small-scale variation of Mg/Ca ratios, which is consistent with growth at constant temperature, suggest a potential application as a palaeotemperature proxy. Cross-growth band element/Ca ratio profiles in the interior of bivalve shells may provide more promising palaeo-environmental tools than sampling from the outer region of bivalve shells.

  2. Differential Distribution of Retinal Ca2+/Calmodulin-Dependent Kinase II (CaMKII Isoforms Indicates CaMKII-β and -δ as Specific Elements of Electrical Synapses Made of Connexin36 (Cx36

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    Stephan Tetenborg

    2017-12-01

    Full Text Available AII amacrine cells are essential interneurons of the primary rod pathway and transmit rod-driven signals to ON cone bipolar cells to enable scotopic vision. Gap junctions made of connexin36 (Cx36 mediate electrical coupling among AII cells and between AII cells and ON cone bipolar cells. These gap junctions underlie a remarkable degree of plasticity and are modulated by different signaling cascades. In particular, Ca2+/calmodulin-dependent protein kinase II (CaMKII has been characterized as an important regulator of Cx36, capable of potentiating electrical coupling in AII cells. However, it is unclear which CaMKII isoform mediates this effect. To obtain a more detailed understanding of the isoform composition of CaMKII at retinal gap junctions, we analyzed the retinal distribution of all four CaMKII isoforms using confocal microscopy. These experiments revealed a differential distribution of CaMKII isoforms: CaMKII-α was strongly expressed in starburst amacrine cells, which are known to lack electrical coupling. CaMKII-β was abundant in OFF bipolar cells, which form electrical synapses in the outer and the inner retina. CaMKII-γ was diffusely distributed across the entire retina and could not be assigned to a specific cell type. CaMKII-δ labeling was evident in bipolar and AII amacrine cells, which contain the majority of Cx36-immunoreactive puncta in the inner retina. We double-labeled retinas for Cx36 and the four CaMKII isoforms and revealed that the composition of the CaMKII enzyme differs between gap junctions in the outer and the inner retina: in the outer retina, only CaMKII-β colocalized with Cx36-containing gap junctions, whereas in the inner retina, CaMKII-β and -δ colocalized with Cx36. This finding suggests that gap junctions in the inner and the outer retina may be regulated differently although they both contain the same connexin. Taken together, our study identifies CaMKII-β and -δ as Cx36-specific regulators in the mouse

  3. Study on the diagnostic value of determination of changes of serum CA125 and CA19-9 levels in patients with endometriosis

    International Nuclear Information System (INIS)

    Liu Aimin

    2008-01-01

    Objective: To explore the diagnostic value of determination of changes of serum CA125 and CA19-9 levels in patients with endometriosis. Methods: Serum CA125 and CA19-9 levels were determined with RIA in 45 patients with endometriosis and 40 controls. Results: Serum levels of CA125 and CA19-9 in patients with endometriosis (89.63 ± 30.16u/ml and 95.62±43.67u/ml respectively) were significantly higher than those (16.26±6.37u/ml and 20.26±8.25u/ml respectively) in controls (P<0. 001). Sensitivity of CA125 for diagnosis of endometriosis was 77.78% and that of CA19-9 was 62.22%, while the specificity was 92.50% and 90.00% respectively. If we only took the patients with both markers elevated as being diagnostically positive, the sensitivity would naturally be lower (57.78%) but the specificity would be 100%. Levels of the markers were significantly higher in stage III, IV patients than those in patients with stage I, II disease (P<0.01). Conclusion: Combined determination of serum CA125 and CA19-9 levels were of highly specific diagnostic value in patients with endometriosis. (authors)

  4. 1,25 (OH)2D3 enhances PTH-induced Ca2+ transients in preosteoblasts by activating L-type Ca2+ channels

    Science.gov (United States)

    Li, W.; Duncan, R. L.; Karin, N. J.; Farach-Carson, M. C.

    1997-01-01

    We previously demonstrated electrophysiologically that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] shifts the activation threshold of L-type Ca2+ channels in osteoblasts toward the resting potential and prolongs mean open time. Presently, we used single-cell Ca2+ imaging to study the combined effects of 1,25(OH)2D3 and parathyroid hormone (PTH) during generation of Ca2+ transients in fura 2-loaded MC3T3-E1 cells. Pretreatment with 1,25(OH)2D3 concentrations, which alone did not produce Ca2+ transients, consistently enhanced Ca2+ responses to PTH. Enhancement was dose dependent over the range of 1 to 10 nM and was blocked by pretreatment with 5 microM nitrendipine during pretreatment. A 1,25(OH)2D3 analog that activates L-type channels and shifts their activation threshold also enhanced PTH responses. In contrast, an analog devoid of membrane Ca2+ effects did not enhance PTH-induced Ca2+ transients. The PTH-induced Ca2+ transient involved activation of a dihydropyridine-insensitive cation channel that was inhibited by Gd3+. Together, these data suggest that 1,25(OH)2D3 increases osteoblast responsiveness to PTH through rapid modification of L-type Ca2+ channel gating properties, whose activation enhances Ca2+ entry through other channels such as the PTH-responsive, Gd(3+)-sensitive cation channel.

  5. Activity-Dependent Phosphorylation by CaMKIIδ Alters the Ca2+ Affinity of the Multi-C2-Domain Protein Otoferlin

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    Sandra Meese

    2017-10-01

    Full Text Available Otoferlin is essential for fast Ca2+-triggered transmitter release from auditory inner hair cells (IHCs, playing key roles in synaptic vesicle release, replenishment and retrieval. Dysfunction of otoferlin results in profound prelingual deafness. Despite its crucial role in cochlear synaptic processes, mechanisms regulating otoferlin activity have not been studied to date. Here, we identified Ca2+/calmodulin-dependent serine/threonine kinase II delta (CaMKIIδ as an otoferlin binding partner by pull-downs from chicken utricles and reassured interaction by a co-immunoprecipitation with heterologously expressed proteins in HEK cells. We confirmed the expression of CaMKIIδ in rodent IHCs by immunohistochemistry and real-time PCR. A proximity ligation assay indicates close proximity of the two proteins in rat IHCs, suggesting that otoferlin and CaMKIIδ also interact in mammalian IHCs. In vitro phosphorylation of otoferlin by CaMKIIδ revealed ten phosphorylation sites, five of which are located within C2-domains. Exchange of serines/threonines at phosphorylated sites into phosphomimetic aspartates reduces the Ca2+ affinity of the recombinant C2F domain 10-fold, and increases the Ca2+ affinity of the C2C domain. Concordantly, we show that phosphorylation of otoferlin and/or its interaction partners are enhanced upon hair cell depolarization and blocked by pharmacological CaMKII inhibition. We therefore propose that otoferlin activity is regulated by CaMKIIδ in IHCs.

  6. Inhibition of the sarcoplasmic reticulum Ca2+ pump with thapsigargin to estimate the contribution of Na+-Ca2+ exchange to ventricular myocyte relaxation

    Directory of Open Access Journals (Sweden)

    Bassani R.A.

    2003-01-01

    Full Text Available Relaxation in the mammalian ventricle is initiated by Ca2+ removal from the cytosol, which is performed by three main transport systems: sarcoplasmic reticulum Ca2+-ATPase (SR-A, Na+-Ca2+ exchanger (NCX and the so-called slow mechanisms (sarcolemmal Ca2+-ATPase and mitochondrial Ca2+ uptake. To estimate the relative contribution of each system to twitch relaxation, SR Ca2+ accumulation must be selectively inhibited, usually by the application of high caffeine concentrations. However, caffeine has been reported to often cause changes in membrane potential due to NCX-generated inward current, which compromises the reliability of its use. In the present study, we estimated integrated Ca2+ fluxes carried by SR-A, NCX and slow mechanisms during twitch relaxation, and compared the results when using caffeine application (Cf-NT and an electrically evoked twitch after inhibition of SR-A with thapsigargin (TG-TW. Ca2+ transients were measured in 20 isolated adult rat ventricular myocytes with indo-1. For transients in which one or more transporters were inhibited, Ca2+ fluxes were estimated from the measured free Ca2+ concentration and myocardial Ca2+ buffering characteristics. NCX-mediated integrated Ca2+ flux was significantly higher with TG-TW than with Cf-NT (12 vs 7 µM, whereas SR-dependent flux was lower with TG-TW (77 vs 81 µM. The relative participations of NCX (12.5 vs 8% with TG-TW and Cf-NT, respectively and SR-A (85 vs 89.5% with TG-TW and Cf-NT, respectively in total relaxation-associated Ca2+ flux were also significantly different. We thus propose TG-TW as a reliable alternative to estimate NCX contribution to twitch relaxation in this kind of analysis.

  7. Establishing the potential of Ca isotopes as proxy for consumption of dairy products

    International Nuclear Information System (INIS)

    Chu, N.-C.; Henderson, Gideon M.; Belshaw, Nick S.; Hedges, Robert E.M.

    2006-01-01

    A procedure has been developed which allows precise determination of Ca isotope ratios in natural and organic samples such as bones, milk and other biological materials. In this study the procedure is used to determine Ca isotope ratios in modern dietary systems and to establish the potential of Ca isotopes as a paleodiet tracer by analysis of bones. Multi-sampling across a 5 cm portion of a red deer jawbone shows invariant Ca isotope ratios and suggests negligible isotopic effect during bone remodelling. The difference between Ca isotopes in red deer diet and bones from one location was 0.65 per mille , in agreement with a previous study of diet/bone offsets. Similar values for modern deer-bone δ 44/42 Ca from four geographically diverse populations demonstrate that geological/environmental conditions do not cause large variability and suggest that diet is the major cause for variations in bone δ 44/42 Ca. δ 44/42 Ca of herbivore milk is found to be ∼0.5 to 0.6 higher than the corresponding diet. Modern human milk has a δ 44/42 Ca of -1.15 (n = 4) and is isotopically the lightest material reported in this study. This suggests that, for these samples, a significant portion of Ca intake was from dairy sources, and that human milk has Ca which is, again, ∼0.6 per mille isotopically lighter than dietary Ca intake. Finally, Ca isotope ratios are presented from a variety of samples formed during fermentation processes (e.g., curds, whey, etc.) which indicate that these processes do not fractionate Ca isotopes significantly. Together, the data in this paper indicate that, because milk is an important dietary source of Ca with a distinctive signature, Ca isotope ratios should provide a tracer for past dairy consumption. A simplified model is outlined to demonstrate the ability to quantify dairy consumption by the analysis of Ca isotopes in bones

  8. In vitro degradation and cytotoxicity of Mg/Ca composites produced by powder metallurgy.

    Science.gov (United States)

    Zheng, Y F; Gu, X N; Xi, Y L; Chai, D L

    2010-05-01

    Mg/Ca (1 wt.%, 5 wt.%, 10 wt.% Ca) composites were prepared from pure magnesium and calcium powders using the powder metallurgy method, aiming to enlarge the addition of Ca content without the formation of Mg(2)Ca. The microstructures, mechanical properties and cytotoxicities of Mg/Ca composite samples were investigated. The corrosion of Mg/Ca composites in Dulbecco's modified Eagle's medium (DMEM) for various immersion intervals was studied by electrochemical impedance spectroscopy measurements and environmental scanning electron microscope, with the concentrations of released Mg and Ca ions in DMEM for various immersion time intervals being measured. It was shown that the main constitutional phases were Mg and Ca, which were uniformly distributed in the Mg matrix. The ultimate tensile strength (UTS) and elongation of experimental composites decreased with increasing Ca content, and the UTS of Mg/1Ca composite was comparable with that of as-extruded Mg-1Ca alloy. The corrosion potential increased with increasing Ca content, whereas the current density and the impedance decreased. It was found that the protective surface film formed quickly at the initial immersion stage. With increasing immersion time, the surface film became compact, and the corrosion rate of Mg/Ca composites slowed down. The surface film consisted mainly of CaCO(3), MgCO(3)x3H(2)O, HA and Mg(OH)(2) after 72 h immersion in DMEM. Mg/1Ca and Mg/5Ca composite extracts had no significant toxicity (p>0.05) to L-929 cells, whereas Mg/10Ca composite extract induced approximately 40% reduced cell viability. Copyright (c) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Resveratrol protects rabbit ventricular myocytes against oxidative stress-induced arrhythmogenic activity and Ca2+ overload.

    Science.gov (United States)

    Li, Wei; Wang, Yue-peng; Gao, Ling; Zhang, Peng-pai; Zhou, Qing; Xu, Quan-fu; Zhou, Zhi-wen; Guo, Kai; Chen, Ren-hua; Yang, Huang-tian; Li, Yi-gang

    2013-09-01

    To investigate whether resveratrol suppressed oxidative stress-induced arrhythmogenic activity and Ca(2+) overload in ventricular myocytes and to explore the underlying mechanisms. Hydrogen peroxide (H2O2, 200 μmol/L)) was used to induce oxidative stress in rabbit ventricular myocytes. Cell shortening and calcium transients were simultaneously recorded to detect arrhythmogenic activity and to measure intracellular Ca(2+) ([Ca(2+)]i). Ca(2+)/calmodulin-dependent protein kinases II (CaMKII) activity was measured using a CaMKII kit or Western blotting analysis. Voltage-activated Na(+) and Ca(2+) currents were examined using whole-cell recording in myocytes. H2O2 markedly prolonged Ca(2+) transient duration (CaTD), and induced early afterdepolarization (EAD)-like and delayed afterdepolarization (DAD)-like arrhythmogenic activity in myocytes paced at 0.16 Hz or 0.5 Hz. Application of resveratrol (30 or 50 μmol/L) dose-dependently suppressed H2O2-induced EAD-like arrhythmogenic activity and attenuated CaTD prolongation. Co-treatment with resveratrol (50 μmol/L) effectively prevented both EAD-like and DAD-like arrhythmogenic activity induced by H2O2. In addition, resveratrol markedly blunted H2O2-induced diastolic [Ca(2+)]i accumulation and prevented the myocytes from developing hypercontracture. In whole-cell recording studies, H2O2 significantly enhanced the late Na(+) current (I(Na,L)) and L-type Ca(2+) current (I(Ca,L)) in myocytes, which were dramatically suppressed or prevented by resveratrol. Furthermore, H2O2-induced ROS production and CaMKII activation were significantly prevented by resveratrol. Resveratrol protects ventricular myocytes against oxidative stress-induced arrhythmogenic activity and Ca(2+) overload through inhibition of I(Na,L)/I(Ca,L), reduction of ROS generation, and prevention of CaMKII activation.

  10. Effect of carticaine on the sarcoplasmic reticulum Ca2+-adenosine triphosphatase. II. Cations dependence.

    Science.gov (United States)

    Takara, Delia; Sánchez, Gabriel A; Toma, Augusto F; Bonazzola, Patricia; Alonso, Guillermo L

    2005-05-01

    Ca2+-ATPase is a major intrinsic protein in the sarcoplasmic reticulum (SR) from skeletal muscles. It actively transports Ca2+ from the cytoplasm to the SR lumen, reducing cytoplasmic [Ca2+] to promote muscle relaxation. Carticaine is a local anesthetic widely used in operative dentistry. We previously showed that carticaine inhibits SR Ca2+-ATPase activity and the coupled Ca(2+) uptake by isolated SR vesicles, and increases the rate of Ca2+ efflux from preloaded vesicles. We also found that these effects were antagonized by divalent cations, and concluded that they were mainly due to the direct interaction of carticaine with the Ca2+-ATPase protein. Here we present additional results on the modulation of the above effects of carticaine by Ca2+ and Mg2+. The activating effect of Ca2+ on the ATPase activity is competitively inhibited by carticaine, indicating a decreased Ca2+ binding to the high affinity Ca2+ transport sites. The activating effect of Mg2+ on the phosphorylation of Ca2+-ATPase by orthophosphate is also inhibited by carticaine. The anesthetic does not affect the reaction mechanism of the cations acting as cofactors of ATP in the catalytic site. On the basis of the present and our previous results, we propose a model that describes the effect of carticaine on the Ca2+-ATPase cycle.

  11. Remodelling of Ca2+ transport in cancer: how it contributes to cancer hallmarks?

    Science.gov (United States)

    Prevarskaya, Natalia; Ouadid-Ahidouch, Halima; Skryma, Roman; Shuba, Yaroslav

    2014-01-01

    Cancer involves defects in the mechanisms underlying cell proliferation, death and migration. Calcium ions are central to these phenomena, serving as major signalling agents with spatial localization, magnitude and temporal characteristics of calcium signals ultimately determining cell's fate. Cellular Ca2+ signalling is determined by the concerted action of a molecular Ca2+-handling toolkit which includes: active energy-dependent Ca2+ transporters, Ca2+-permeable ion channels, Ca2+-binding and storage proteins, Ca2+-dependent effectors. In cancer, because of mutations, aberrant expression, regulation and/or subcellular targeting of Ca2+-handling/transport protein(s) normal relationships among extracellular, cytosolic, endoplasmic reticulum and mitochondrial Ca2+ concentrations or spatio-temporal patterns of Ca2+ signalling become distorted. This causes deregulation of Ca2+-dependent effectors that control signalling pathways determining cell's behaviour in a way to promote pathophysiological cancer hallmarks such as enhanced proliferation, survival and invasion. Despite the progress in our understanding of Ca2+ homeostasis remodelling in cancer cells as well as in identification of the key Ca2+-transport molecules promoting certain malignant phenotypes, there is still a lot of work to be done to transform fundamental findings and concepts into new Ca2+ transport-targeting tools for cancer diagnosis and treatment. PMID:24493745

  12. Thermodynamic, electronic, and magnetic properties of intrinsic vacancy defects in antiperovskite Ca3SnO

    Science.gov (United States)

    Batool, Javaria; Alay-e-Abbas, Syed Muhammad; Amin, Nasir

    2018-04-01

    The density functional theory based total energy calculations are performed to examine the effect of charge neutral and fully charged intrinsic vacancy defects on the thermodynamic, electronic, and magnetic properties of Ca3SnO antiperovskite. The chemical stability of Ca3SnO is evaluated with respect to binary compounds CaO, CaSn, and Ca2Sn, and the limits of atomic chemical potentials of Ca, Sn, and O atoms for stable synthesis of Ca3SnO are determined within the generalized gradient approximation parametrization scheme. The electronic properties of the pristine and the non-stoichiometric forms of this compound have been explored and the influence of isolated intrinsic vacancy defects (Ca, Sn, and O) on the structural, bonding, and electronic properties of non-stoichiometric Ca3SnO are analyzed. We also predict the possibility of achieving stable ferromagnetism in non-stoichiometric Ca3SnO by means of charge neutral tin vacancies. From the calculated total energies and the valid ranges of atomic chemical potentials, the formation energetics of intrinsic vacancy defects in Ca3SnO are evaluated for various growth conditions. Our results indicate that the fully charged calcium vacancies are thermodynamically stable under the permissible Sn-rich condition of stable synthesis of Ca3SnO, while tin and oxygen vacancies are found to be stable under the extreme Ca-rich condition.

  13. Cyclic GMP alters Ca exchange in vascular smooth muscle

    International Nuclear Information System (INIS)

    Magliola, L.; Bailey, B.; Jones, A.W.

    1986-01-01

    Contraction and 42 K efflux from vascular smooth muscle stimulated either by norepinephrine (NE) or by K-depolarization is dependent on an increase in cytosolic Ca concentration. The purpose of this study was to determine if cyclic GMP (cGMP) inhibited these processes and if inhibition was secondary to the action of cGMP on Ca movements. Basal cGMP content of rat aorta was 1.2 fmol/mg wet wt. Sodium nitroprusside (NP) increased cGMP ∼2-fold at 1 nM and ∼750-fold at 1 μM with no effect on cAMP levels. A 5 min pretreatment with NP (1 μM) completely prevented tension development induced by 3 μM NE. The same concentration of NP also inhibited NE-stimulated 42 K and 45 Ca efflux > 90 and > 80%, respectively. Removal of NP in the continued presence of NE (3 μM) caused recovery of the 42 K efflux response to ∼75% of control with a half-time of ∼2.5 min. NP (1 μM) also caused a rapid relaxation of aorta contracted with 3 μM NE and a loss of the 42 K efflux response with half-times of 2-3 min. In contrast, 100 μM NP produced only a 50% inhibition of contraction induced by high K (55 mM). Also, NP (1 μM) inhibited K-stimulated 42 K efflux only ∼25%. These results demonstrate both a concentration- and a time-dependent relationship between increases in cGMP induced by NP and decreases in NE-stimulated contraction, 42 K and 45 Ca effluxes. They also indicate that the sensitivity of NE-induced contraction and 42 K efflux to NP is greater than that induced by high K. These studies suggest that cGMP modulates the control sites for Ca exchange in the plasma membrane and sarcoplasmic reticulum

  14. Analysis of decay chains of superheavy nuclei produced in the 249Bk+48Ca and 243Am+48Ca reactions

    International Nuclear Information System (INIS)

    Zlokazov, V B; Utyonkov, V K

    2017-01-01

    The analysis of decay chains starting at superheavy nuclei 293 Ts and 289 Mc is presented. The spectroscopic properties of nuclei identified during the experiments using the 249 Bk+ 48 Ca and 243 Am+ 48 Ca reactions studied at the gas-filled separators DGFRS, TASCA and BGS are considered. We present the analysis of decay data using widely adopted statistical methods and applying them to the short decay chains of parent odd- Z nuclei. We find out that the recently suggested method of analyzing decay chains by Forsberg et al may lead to questionable conclusions when applied for the analysis of radioactive decays. Our discussion demonstrates reasonable congruence of α -particle energies and decay times of nuclei assigned to isotopes 289 Mc, 285 Nh and 281 Rg observed in both reactions. (paper)

  15. Analysis of decay chains of superheavy nuclei produced in the 249Bk+48Ca and 243Am+48Ca reactions

    Science.gov (United States)

    Zlokazov, V. B.; Utyonkov, V. K.

    2017-07-01

    The analysis of decay chains starting at superheavy nuclei 293Ts and 289Mc is presented. The spectroscopic properties of nuclei identified during the experiments using the 249Bk+48Ca and 243Am+48Ca reactions studied at the gas-filled separators DGFRS, TASCA and BGS are considered. We present the analysis of decay data using widely adopted statistical methods and applying them to the short decay chains of parent odd-Z nuclei. We find out that the recently suggested method of analyzing decay chains by Forsberg et al may lead to questionable conclusions when applied for the analysis of radioactive decays. Our discussion demonstrates reasonable congruence of α-particle energies and decay times of nuclei assigned to isotopes 289Mc, 285Nh and 281Rg observed in both reactions.

  16. Performance of CaSO{sub 4}:Dy detectors; Desempenho de detectores de CaSO{sub 4}:Dy

    Energy Technology Data Exchange (ETDEWEB)

    Setti, M.C.; Silva, G.R.; Pela, C.A.; Bruco, J.L. [Sao Paulo Univ. (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Centro de Instrumentacao, Dosimetria e Radioprotecao (CIDRA); Borges, J.C. [Fapesp, Sao Paulo, SP (Brazil)

    2004-07-01

    CaSO{sub 4}:Dy detectors have been used in personal dosimetry. The MRA company recently entered into the market of these detectors. Searching to assure a product quality level that would satisfy its customs most expectancies, MRA programmed several tests to qualify and quantify these detectors main characteristics, before their definitive insertion in the market. Preliminary tests furnished a value of 29,5 {+-} 1,2 nC for homogeneity and a maximum dispersion of 3 % for linearity . (author)

  17. Lactucopicrin potentiates neuritogenesis and neurotrophic effects by regulating Ca2+/CaMKII/ATF1 signaling pathway.

    Science.gov (United States)

    Venkatesan, Ramu; Shim, Won-Sik; Yeo, Eui-Ju; Kim, Sun Yeou

    2017-02-23

    Lactucopicrin is one of constitutes in Cichorium intybus L, which is commonly known as chicory in worldwide. It has been used for traditional usage such as antianalgesics, antidepressants and antihyperglycemics AIM OF STUDY: We investigated the neurotrophin-mediated neuroprotective effect of lactucopicrin in in vitro and examined for the underlying mechanism. To verify the neuroprotective effect of lactucopicrin, we investigated the inhibitory AChE activity, neurite outgrowth-related downstream signaling in murine neuroblastoma N2a and neurotrophins secretion in rat C6 glioma cells. Lactucopicrin inhibited the AChE activity and increased intracellular Ca 2+ levels with a substantial rise in muscarinic acetylcholine receptor M1 (CHRM1) expression in N2a cells. Moreover, lactucopicrin actively promoted neurite outgrowth via Ca 2+ -mediated activation of Ca 2+ /calmodulin-dependent protein kinase-II (CaMKII). It further activates transcription factor 1 (ATF1) along with modulating the levels of tropomyosin receptor kinase A, extracellular signal-regulated kinase 1 and 2, AKT, and synaptophysin 1 in N2a cells. Additionally, the levels of neurotrophins including NGF, BDNF, and NT3 were increased by treatment of lactucopicrin in C6 cells. The effects of lactucopicrin on NGF secretion and neuritogenesis were maintained even in the presence of phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002, indicating that lactucopicrin exerts its effect on neuritogenesis in a PI3K-independent manner. Our results suggest that the natural compound lactucopicrin may be a promising neurotrophin-mediated neuroprotective candidate for neurodegenerative diseases. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  18. NiF2/NaF:CaF2/Ca Solid-State High-Temperature Battery Cells

    Science.gov (United States)

    West, William; Whitacre, Jay; DelCastillo, Linda

    2009-01-01

    Experiments and theoretical study have demonstrated the promise of all-solid-state, high-temperature electrochemical battery cells based on NiF2 as the active cathode material, CaF2 doped with NaF as the electrolyte material, and Ca as the active anode material. These and other all-solid-state cells have been investigated in a continuing effort to develop batteries for instruments that must operate in environments much hotter than can be withstood by ordinary commercially available batteries. Batteries of this type are needed for exploration of Venus (where the mean surface temperature is about 450 C), and could be used on Earth for such applications as measuring physical and chemical conditions in geothermal wells and oil wells. All-solid-state high-temperature power cells are sought as alternatives to other high-temperature power cells based, variously, on molten anodes and cathodes or molten eutectic salt electrolytes. Among the all-solid-state predecessors of the present NiF2/NaF:CaF2/Ca cells are those described in "Solid-State High-Temperature Power Cells" (NPO-44396), NASA Tech Briefs, Vol. 32, No. 5 (May 2008), page 40. In those cells, the active cathode material is FeS2, the electrolyte material is a crystalline solid solution of equimolar amounts of Li3PO4 and LiSiO4, and the active anode material is Li contained within an alloy that remains solid in the intended high operational temperature range.

  19. Ca2+/calmodulin-dependent kinase II-dependent regulation of atrial myocyte late Na+current, Ca2+cycling, and excitability: a mathematical modeling study.

    Science.gov (United States)

    Onal, Birce; Gratz, Daniel; Hund, Thomas J

    2017-12-01

    Atrial fibrillation (AF) affects more than three million people per year in the United States and is associated with high morbidity and mortality. Both electrical and structural remodeling contribute to AF, but the molecular pathways underlying AF pathogenesis are not well understood. Recently, a role for Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) in the regulation of persistent "late" Na + current ( I Na,L ) has been identified. Although I Na,L inhibition is emerging as a potential antiarrhythmic strategy in patients with AF, little is known about the mechanism linking I Na,L to atrial arrhythmogenesis. A computational approach was used to test the hypothesis that increased CaMKII-activated I Na,L in atrial myocytes disrupts Ca 2+ homeostasis, promoting arrhythmogenic afterdepolarizations. Dynamic CaMKII activity and regulation of multiple downstream targets [ I Na,L , L-type Ca 2+ current, phospholamban, and the ryanodine receptor sarcoplasmic reticulum Ca 2+ -release channel (RyR2)] were incorporated into an existing well-validated computational model of the human atrial action potential. Model simulations showed that constitutive CaMKII-dependent phosphorylation of Na v 1.5 and the subsequent increase in I Na,L effectively disrupt intracellular atrial myocyte ion homeostasis and CaMKII signaling. Specifically, increased I Na,L promotes intracellular Ca 2+ overload via forward-mode Na + /Ca 2+ exchange activity, which greatly increases RyR2 open probability beyond that observed for CaMKII-dependent phosphorylation of RyR2 alone. Increased I Na,L promotes atrial myocyte repolarization defects (afterdepolarizations and alternans) in the setting of acute β-adrenergic stimulation. We anticipate that our modeling efforts will help identify new mechanisms for atrial Na V 1.5 regulation with direct relevance for human AF. NEW & NOTEWORTHY Here, we present a novel computational model to study the effects of late Na + current ( I Na,L ) in human atrial

  20. Mitochondrial Ca2+ uniporter is critical for store-operated Ca2+ entry-dependent breast cancer cell migration

    International Nuclear Information System (INIS)

    Tang, Shihao; Wang, Xubu; Shen, Qiang; Yang, Xinyi; Yu, Changhui; Cai, Chunqing; Cai, Guoshuai; Meng, Xiaojing; Zou, Fei

    2015-01-01

    Metastasis of cancer cells is a complicated multistep process requiring extensive and continuous cytosolic calcium modulation. Mitochondrial Ca 2+ uniporter (MCU), a regulator of mitochondrial Ca 2+ uptake, has been implicated in energy metabolism and various cellular signaling processes. However, whether MCU contributes to cancer cell migration has not been established. Here we examined the expression of MCU mRNA in the Oncomine database and found that MCU is correlated to metastasis and invasive breast cancer. MCU inhibition by ruthenium red (RuR) or MCU silencing by siRNA abolished serum-induced migration in MDA-MB-231 breast cancer cells and reduced serum- or thapsigargin (TG)-induced store-operated Ca2+ entry (SOCE). Serum-induced migrations in MDA-MB-231 cells were blocked by SOCE inhibitors. Our results demonstrate that MCU plays a critical role in breast cancer cell migration by regulating SOCE. - Highlights: • MCU is correlated to metastasis and invasive breast cancer. • MCU inhibition abolished serum-induced migration in MDA-MB-231 breast cancer cells and reduced serum- or TG-induced SOCE. • Serum-induced migrations in MDA-MB-231 cells were blocked by SOCE inhibitors. • MCU plays a critical role in MDA-MB-231 cell migration by regulating SOCE

  1. Electric Field Control of Interfacial Ferromagnetism in CaMnO3/CaRuO3 Heterostructures

    Science.gov (United States)

    Grutter, A. J.; Kirby, B. J.; Gray, M. T.; Flint, C. L.; Alaan, U. S.; Suzuki, Y.; Borchers, J. A.

    2015-07-01

    New mechanisms for achieving direct electric field control of ferromagnetism are highly desirable in the development of functional magnetic interfaces. To that end, we have probed the electric field dependence of the emergent ferromagnetic layer at CaRuO3/CaMnO3 interfaces in bilayers fabricated on SrTiO3. Using polarized neutron reflectometry, we are able to detect the ferromagnetic signal arising from a single atomic monolayer of CaMnO3, manifested as a spin asymmetry in the reflectivity. We find that the application of an electric field of 600 kV /m across the bilayer induces a significant increase in this spin asymmetry. Modeling of the reflectivity suggests that this increase corresponds to a transition from canted antiferromagnetism to full ferromagnetic alignment of the Mn4 + ions at the interface. This increase from 1 μB to 2.5 - 3.0 μB per Mn is indicative of a strong magnetoelectric coupling effect, and such direct electric field control of the magnetization at an interface has significant potential for spintronic applications.

  2. Magnetoresistance and magnetothermopower properties of Bi/Ca/Co/O and Bi(Pb)/Ca/Co/O misfit layer cobaltites

    CERN Document Server

    Maignan, A; Hervieu, M; Michel, C; Pelloquin, D; Khomskii, D

    2003-01-01

    Two new compounds of the Bi/Ca/Co/O and Bi(Pb)/Ca/Co/O systems have been prepared. Their structure is built up from the intergrowth of four rock-salt-type layers and one [CoO sub 2 ] hexagonal layer. Both cobaltites exhibit large thermopower values (S sub 3 sub 0 sub 0 sub K approx 140 mu V K sup - sup 1), low resistivity values (rho sub 3 sub 0 sub 0 sub K = 40-60 m OMEGA cm) and small thermal conductivities (kappa sub 3 sub 0 sub 0 sub K approx 1 W K sup - sup 1 m sup - sup 1). Furthermore, these compounds exhibit a negative magnetoresistance, (MR = rho sub H - rho sub H sub sub 0 /rho sub H sub = sub 0), reaching, at 2.5 K, - 85% in 7 T for the Bi/Ca/Co/O misfit cobaltite. A large negative magnetothermopower is also found for these cobaltites in the same temperature range. A qualitative explanation of the observed behaviour is proposed.

  3. Chronic fluoxetine administration enhances synaptic plasticity and increases functional dynamics in hippocampal CA3-CA1 synapses.

    Science.gov (United States)

    Popova, Dina; Castrén, Eero; Taira, Tomi

    2017-11-01

    Recent studies demonstrate that chronic administration of the widely used antidepressant fluoxetine (FLX) promotes neurogenesis, synaptogenesis and synaptic plasticity in the adult hippocampus, cortex and amygdala. However, the mechanisms underlying these effects and how are they related to the clinical antidepressant efficacy are still poorly understood. We show here that chronic FLX administration decreases hippocampus-associated neophobia in naïve mice. In parallel, electrophysiological recordings in hippocampal CA3-CA1 circuitry revealed that the FLX treatment resulted in increased short- and long-term plasticity likely attributed to changes in presynaptic function. These changes were accompanied by enhancement in the expression of proteins related to vesicular trafficking and release, namely synaptophysin, synaptotagmin 1, MUNC 18 and syntaxin 1. Thus, chronic FLX administration is associated with enhanced synaptic dynamics atypical of mature CA1 synapses, elevated hippocampal plasticity, improved hippocampus-dependent behavior as well as altered expression of synaptic proteins regulating neurotransmitter trafficking and release. The results support the idea that antidepressants can promote neuronal plasticity and show that they can increase the functional dynamic range and information processing in synaptic circuitries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Sphingosine inhibits the sarco(endo)plasmic reticulum Ca{sup 2+}-ATPase (SERCA) activity

    Energy Technology Data Exchange (ETDEWEB)

    Benaim, Gustavo, E-mail: gbenaim@idea.gob.ve [Instituto de Estudios Avanzados (IDEA), Caracas (Venezuela, Bolivarian Republic of); Instituto de Biología Experimental, Facultad de Ciencias, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of); Pimentel, Adriana A., E-mail: adriana.pimentel@ucv.ve [Facultad de Farmacia, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of); Felibertt, Pimali [Facultad de Ciencias, Universidad de Carabobo, Valencia (Venezuela, Bolivarian Republic of); Mayora, Adriana [Instituto de Biología Experimental, Facultad de Ciencias, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of); Colman, Laura [Instituto Pasteur de Montevideo, Montevideo (Uruguay); Sojo, Felipe [Instituto de Biología Experimental, Facultad de Ciencias, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of); Rojas, Héctor [Instituto de Inmunología, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of); Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas (Venezuela, Bolivarian Republic of); De Sanctis, Juan B. [Instituto de Inmunología, Universidad Central de Venezuela (UCV), Caracas (Venezuela, Bolivarian Republic of)

    2016-04-29

    The increase in the intracellular Ca{sup 2+} concentration ([Ca{sup 2+}]{sub i}) is the key variable for many different processes, ranging from regulation of cell proliferation to apoptosis. In this work we demonstrated that the sphingolipid sphingosine (Sph) increases the [Ca{sup 2+}]{sub i} by inhibiting the sarco(endo)plasmic reticulum Ca{sup 2+}-ATPase (SERCA), in a similar manner to thapsigargin (Tg), a specific inhibitor of this Ca{sup 2+} pump. The results showed that addition of sphingosine produced a release of Ca{sup 2+} from the endoplasmic reticulum followed by a Ca{sup 2+} entrance from the outside mileu. The results presented in this work support that this sphingolipid could control the activity of the SERCA, and hence sphingosine may participate in the regulation of [Ca{sup 2+}]{sub I} in mammalian cells.

  5. Sphingosine inhibits the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) activity

    International Nuclear Information System (INIS)

    Benaim, Gustavo; Pimentel, Adriana A.; Felibertt, Pimali; Mayora, Adriana; Colman, Laura; Sojo, Felipe; Rojas, Héctor; De Sanctis, Juan B.

    2016-01-01

    The increase in the intracellular Ca 2+ concentration ([Ca 2+ ] i ) is the key variable for many different processes, ranging from regulation of cell proliferation to apoptosis. In this work we demonstrated that the sphingolipid sphingosine (Sph) increases the [Ca 2+ ] i by inhibiting the sarco(endo)plasmic reticulum Ca 2+ -ATPase (SERCA), in a similar manner to thapsigargin (Tg), a specific inhibitor of this Ca 2+ pump. The results showed that addition of sphingosine produced a release of Ca 2+ from the endoplasmic reticulum followed by a Ca 2+ entrance from the outside mileu. The results presented in this work support that this sphingolipid could control the activity of the SERCA, and hence sphingosine may participate in the regulation of [Ca 2+ ] I in mammalian cells.

  6. 76 FR 58240 - Modoc National Forest, Alturas, CA, Supplemental Information for the Final Environmental Impact...

    Science.gov (United States)

    2011-09-20

    ... DEPARTMENT OF AGRICULTURE Forest Service Modoc National Forest, Alturas, CA, Supplemental Information for the Final Environmental Impact Statement (FEIS) Motorized Travel Management AGENCY: Forest... written comments to Modoc National Forest, Supplemental Travel Management, 800 W. 12th Street, Alturas, CA...

  7. Thermal Protection System Materials (TPSM): Conformal Ablative TPS (CA-TPS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CA-TPS is leveraging earlier investments made by ARMD’s Hypersonic and HEOMD’s ETDD program that matured the concept from TRL 1 to 2.CA-TPS starts with...

  8. 75 FR 30689 - Modification of Class C Airspace; Beale Air Force Base, CA

    Science.gov (United States)

    2010-06-02

    ... Base, CA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action modifies the legal description of the Beale Air Force Base (AFB), CA, Class C airspace area by allowing the...

  9. The role of CA 125 and conventional examinations in diagnosing progressive carcinoma of the ovary

    NARCIS (Netherlands)

    van der Burg, M. E.; Lammes, F. B.; Verweij, J.

    1993-01-01

    The clinical significance of the serum marker CA 125 and conventional examinations in diagnosing progressive disease was evaluated in 98 patients. The examinations included CA 125, gynecologic and complete physical examination, abdominal computed tomography (CT), roentgenogram of the chest, second

  10. Acetylcholine promotes Ca2+ and NO-oscillations in adipocytes implicating Ca2+→NO→cGMP→cADP-ribose→Ca2+ positive feedback loop--modulatory effects of norepinephrine and atrial natriuretic peptide.

    Directory of Open Access Journals (Sweden)

    Egor A Turovsky

    Full Text Available This study investigated possible mechanisms of autoregulation of Ca(2+ signalling pathways in adipocytes responsible for Ca(2+ and NO oscillations and switching phenomena promoted by acetylcholine (ACh, norepinephrine (NE and atrial natriuretic peptide (ANP.Fluorescent microscopy was used to detect changes in Ca(2+ and NO in cultures of rodent white adipocytes. Agonists and inhibitors were applied to characterize the involvement of various enzymes and Ca(2+-channels in Ca(2+ signalling pathways.ACh activating M3-muscarinic receptors and Gβγ protein dependent phosphatidylinositol 3 kinase induces Ca(2+ and NO oscillations in adipocytes. At low concentrations of ACh which are insufficient to induce oscillations, NE or α1, α2-adrenergic agonists act by amplifying the effect of ACh to promote Ca(2+ oscillations or switching phenomena. SNAP, 8-Br-cAMP, NAD and ANP may also produce similar set of dynamic regimes. These regimes arise from activation of the ryanodine receptor (RyR with the implication of a long positive feedback loop (PFL: Ca(2+→NO→cGMP→cADPR→Ca(2+, which determines periodic or steady operation of a short PFL based on Ca(2+-induced Ca(2+ release via RyR by generating cADPR, a coagonist of Ca(2+ at the RyR. Interplay between these two loops may be responsible for the observed effects. Several other PFLs, based on activation of endothelial nitric oxide synthase or of protein kinase B by Ca(2+-dependent kinases, may reinforce functioning of main PFL and enhance reliability. All observed regimes are independent of operation of the phospholipase C/Ca(2+-signalling axis, which may be switched off due to negative feedback arising from phosphorylation of the inositol-3-phosphate receptor by protein kinase G.This study presents a kinetic model of Ca(2+-signalling system operating in adipocytes and integrating signals from various agonists, which describes it as multivariable multi feedback network with a family of nested positive

  11. Lifetimes of the first and second excited 3/2- states in 41Ca using the 2H(40Ca,p)41Ca reaction

    International Nuclear Information System (INIS)

    Beck, F.A.; Byrski, T.; Toulemonde, M.; Vivien, J.P.

    1978-01-01

    A high velocity shift attenuation experiment was performed using an inverse reaction with a 40 Ca ion beam on a deuteron target. The mean lives of the two first 3/2 - level at 1943 and 2462keV have been determined as 0.79+-0.10 and 6.7+-0.8 psec respectively. Concurrently the lifetime of the 2670keV level was found to be 4.5+-1.3psec. An empirical electric quadrupole charge is extracted for the neutron from the 1943(3/2 - )→g.s.(7/2 - ) γ-ray transition probability using a shell model wave function in the fp space

  12. Effect of vanadate and of removal of extracellular Ca2+ and Na+ on tension development and 45Ca efflux in rat and frog myocardium

    DEFF Research Database (Denmark)

    Gesser, H; Bonefeld-Jørgensen, Eva Cecilie

    1983-01-01

    Vanadate in the range 0-5 mM has positive inotropic effects on myocardial strips of frog and to a lesser extent on those of rat. Inhibiting the sarcolemmal Na+, Ca2+ exchange by a solution free of Ca2+ and Na+ caused a drop in 45Ca efflux and a transient increase in resting tension. These effects...... were more expressed for the frog than for the rat myocardium, which suggests that the Na+ for Ca2+ exchange across the cell membrane is more important in the frog than in the rat myocardium. A subsequent addition of vanadate at 2 or 5 mM had no effect on 45Ca efflux, while it increased the resting...... tension. This increase was higher for the frog than for the rat myocardium. These results suggest that the inotropic effects of vanadate may be due to an effect on membrane-bound Ca2+-ATPase....

  13. Distinct roles of two ceramide synthases, CaLag1p and CaLac1p, in the morphogenesis of Candida albicans

    DEFF Research Database (Denmark)

    Cheon, Seon Ah; Bal, Jyotiranjan; Song, Yunkyoung

    2012-01-01

    Lag1p and Lac1p catalyse ceramide synthesis in Saccharomyces cerevisiae. This study shows that Lag1 family proteins are generally required for polarized growth in hemiascomycetous yeast. However, in contrast to S. cerevisiae where these proteins are functionally redundant, C. albicans Lag1p (CaLag1......p) and Lac1p (CaLac1p) are functionally distinct. Lack of CaLag1p, but not CaLac1p, caused severe defects in the growth and hyphal morphogenesis of C. albicans. Deletion of CaLAG1 decreased expression of the hypha-specific HWP1 and ECE1 genes. Moreover, overexpression of CaLAG1 induced pseudohyphal....... albicans....

  14. Ca(2+ release events in cardiac myocytes up close: insights from fast confocal imaging.

    Directory of Open Access Journals (Sweden)

    Vyacheslav M Shkryl

    Full Text Available The spatio-temporal properties of Ca(2+ transients during excitation-contraction coupling and elementary Ca(2+ release events (Ca(2+ sparks were studied in atrial and ventricular myocytes with ultra-fast confocal microscopy using a Zeiss LSM 5 LIVE system that allows sampling rates of up to 60 kHz. Ca(2+ sparks which originated from subsarcolemmal junctional sarcoplasmic reticulum (j-SR release sites in atrial myocytes were anisotropic and elongated in the longitudinal direction of the cell. Ca(2+ sparks in atrial cells originating from non-junctional SR and in ventricular myocytes were symmetrical. Ca(2+ spark recording in line scan mode at 40,000 lines/s uncovered step-like increases of [Ca(2+]i. 2-D imaging of Ca(2+ transients revealed an asynchronous activation of release sites and allowed the sequential recording of Ca(2+ entry through surface membrane Ca(2+ channels and subsequent activation of Ca(2+-induced Ca(2+ release. With a latency of 2.5 ms after application of an electrical stimulus, Ca(2+ entry could be detected that was followed by SR Ca(2+ release after an additional 3 ms delay. Maximum Ca(2+ release was observed 4 ms after the beginning of release. The timing of Ca(2+ entry and release was confirmed by simultaneous [Ca(2+]i and membrane current measurements using the whole cell voltage-clamp technique. In atrial cells activation of discrete individual release sites of the j-SR led to spatially restricted Ca(2+ release events that fused into a peripheral ring of elevated [Ca(2+]i that subsequently propagated in a wave-like fashion towards the center of the cell. In ventricular myocytes asynchronous Ca(2+ release signals from discrete sites with no preferential subcellular location preceded the whole-cell Ca(2+ transient. In summary, ultra-fast confocal imaging allows investigation of Ca(2+ signals with a time resolution similar to patch clamp technique, however in a less invasive fashion.

  15. Targeting the CaMKII/ERK Interaction in the Heart Prevents Cardiac Hypertrophy

    Science.gov (United States)

    Cipolletta, Ersilia; Rusciano, Maria Rosaria; Maione, Angela Serena; Santulli, Gaetano; Sorriento, Daniela; Del Giudice, Carmine; Ciccarelli, Michele; Franco, Antonietta; Crola, Catherine; Campiglia, Pietro; Sala, Marina; Gomez-Monterrey, Isabel; De Luca, Nicola; Trimarco, Bruno; Iaccarino, Guido; Illario, Maddalena

    2015-01-01

    Aims Activation of Ca2+/Calmodulin protein kinase II (CaMKII) is an important step in signaling of cardiac hypertrophy. The molecular mechanisms by which CaMKII integrates with other pathways in the heart are incompletely understood. We hypothesize that CaMKII association with extracellular regulated kinase (ERK), promotes cardiac hypertrophy through ERK nuclear localization. Methods and Results In H9C2 cardiomyoblasts, the selective CaMKII peptide inhibitor AntCaNtide, its penetratin conjugated minimal inhibitory sequence analog tat-CN17β, and the MEK/ERK inhibitor UO126 all reduce phenylephrine (PE)-mediated ERK and CaMKII activation and their interaction. Moreover, AntCaNtide or tat-CN17β pretreatment prevented PE induced CaMKII and ERK nuclear accumulation in H9C2s and reduced the hypertrophy responses. To determine the role of CaMKII in cardiac hypertrophy in vivo, spontaneously hypertensive rats were subjected to intramyocardial injections of AntCaNtide or tat-CN17β. Left ventricular hypertrophy was evaluated weekly for 3 weeks by cardiac ultrasounds. We observed that the treatment with CaMKII inhibitors induced similar but significant reduction of cardiac size, left ventricular mass, and thickness of cardiac wall. The treatment with CaMKII inhibitors caused a significant reduction of CaMKII and ERK phosphorylation levels and their nuclear localization in the heart. Conclusion These results indicate that CaMKII and ERK interact to promote activation in hypertrophy; the inhibition of CaMKII-ERK interaction offers a novel therapeutic approach to limit cardiac hypertrophy. PMID:26110816

  16. Targeting the CaMKII/ERK Interaction in the Heart Prevents Cardiac Hypertrophy.

    Directory of Open Access Journals (Sweden)

    Ersilia Cipolletta

    Full Text Available Activation of Ca2+/Calmodulin protein kinase II (CaMKII is an important step in signaling of cardiac hypertrophy. The molecular mechanisms by which CaMKII integrates with other pathways in the heart are incompletely understood. We hypothesize that CaMKII association with extracellular regulated kinase (ERK, promotes cardiac hypertrophy through ERK nuclear localization.In H9C2 cardiomyoblasts, the selective CaMKII peptide inhibitor AntCaNtide, its penetratin conjugated minimal inhibitory sequence analog tat-CN17β, and the MEK/ERK inhibitor UO126 all reduce phenylephrine (PE-mediated ERK and CaMKII activation and their interaction. Moreover, AntCaNtide or tat-CN17β pretreatment prevented PE induced CaMKII and ERK nuclear accumulation in H9C2s and reduced the hypertrophy responses. To determine the role of CaMKII in cardiac hypertrophy in vivo, spontaneously hypertensive rats were subjected to intramyocardial injections of AntCaNtide or tat-CN17β. Left ventricular hypertrophy was evaluated weekly for 3 weeks by cardiac ultrasounds. We observed that the treatment with CaMKII inhibitors induced similar but significant reduction of cardiac size, left ventricular mass, and thickness of cardiac wall. The treatment with CaMKII inhibitors caused a significant reduction of CaMKII and ERK phosphorylation levels and their nuclear localization in the heart.These results indicate that CaMKII and ERK interact to promote activation in hypertrophy; the inhibition of CaMKII-ERK interaction offers a novel therapeutic approach to limit cardiac hypertrophy.

  17. Bergmann glia modulate cerebellar Purkinje cell bistability via Ca2+-dependent K+ uptake

    OpenAIRE

    Wang, Fushun; Xu, Qiwu; Wang, Weishan; Takano, Takahiro; Nedergaard, Maiken

    2012-01-01

    Recent studies have shown that cerebellar Bergmann glia display coordinated Ca2+ transients in live mice. However, the functional significance of Bergmann glial Ca2+ signaling remains poorly understood. Using transgenic mice that allow selective stimulation of glial cells, we report here that cytosolic Ca2+ regulates uptake of K+ by Bergmann glia, thus providing a powerful mechanism for control of Purkinje cell-membrane potential. The decline in extracellular K+ evoked by agonist-induced Ca2+...

  18. Ca2+ Transport by Mitochondria from L1210 Mouse Ascites Tumor Cells

    Science.gov (United States)

    Reynafarje, Baltazar; Lehninger, Albert L.

    1973-01-01

    Mitochondria isolated from the ascites form of L1210 mouse leukemia cells readily accumulate Ca2+ from the suspending medium and eject H+ during oxidation of succinate in the presence of phosphate and Mg2+, with normal stoichiometry between Ca2+ uptake and electron transport. Ca2+ loads up to 1600 ng-atoms per mg of protein are attained. As is the case in mitochondria from normal tissues, Ca2+ uptake takes precedence over oxidative phosphorylation. However, Ca2+ transport by the L-1210 mitochondria is unusual in other respects, which may possibly have general significance in tumor cells. The apparent affinity of the L1210 mitochondria for Ca2+ in stimulation of oxygen uptake is about 3-fold greater than in normal liver mitochondria; moreover, the maximal rate of Ca2+ transport is also considerably higher. Furthermore, when Ca2+ pulses are added to L1210 mitochondria in the absence of phosphate or other permeant anions, much larger amounts of Ca2+ are bound and H+ ejected per atom of oxygen consumed than in the presence of phosphate; up to 7 Ca2+ ions are bound per pair of electrons passing each energy-conserving site of the electron-transport chain. Such “superstoichiometry” of Ca2+ uptake can be accounted for by two distinct types of respiration-dependent interaction of Ca2+ with the L1210 mitochondria. One is the stimulation of oxygen consumption, which is achieved by relatively low concentrations of Ca2+ (Km ≅ 8 μM) and is accompanied by binding of Ca2+ up to 40 ng-atoms per mg of protein. The second process, also dependent on electron transport, is the binding of further Ca2+ from the medium in exchange with previously stored membrane-bound protons, in which the affinity for Ca2+ is much lower (Km ≅ 120 μM). PMID:4515933

  19. Environmental and cortisol-mediated control of Ca(2+) uptake in tilapia (Oreochromis mossambicus).

    Science.gov (United States)

    Lin, Chia-Hao; Kuan, Wei-Chun; Liao, Bo-Kai; Deng, Ang-Ni; Tseng, Deng-Yu; Hwang, Pung-Pung

    2016-04-01

    Ca(2+) is a vital element for many physiological processes in vertebrates, including teleosts, which live in aquatic environments and acquire Ca(2+) from their surroundings. Ionocytes within the adult gills or larval skin are critical sites for transcellular Ca(2+) uptake in teleosts. The ionocytes of zebrafish were found to contain transcellular Ca(2+) transporters, epithelial Ca(2+) channel (ECaC), plasma membrane Ca(2+)-ATPase 2 (PMCA2), and Na(+)/Ca(2+) exchanger 1b (NCX1b), providing information about the molecular mechanism of transcellular Ca(2+) transports mediated by ionocytes in fish. However, more evidence is required to establish whether or not a similar mechanism of transcellular Ca(2+) transport also exists in others teleosts. In the present study, ecac, pmca2, and ncx1 were found to be expressed in the branchial ionocytes of tilapia, thereby providing further support for the mechanism of transcellular Ca(2+) transport through ionocytes previously proposed for zebrafish. In addition, we also reveal that low Ca(2+) water treatment of tilapia stimulates Ca(2+) uptake and expression of ecac and cyp11b (the latter encodes a cortisol-synthesis enzyme). Treatment of tilapia with exogenous cortisol (20 mg/l) enhanced both Ca(2+) influx and ecac expression. Therefore, increased cyp11b expression is suggested to enhance Ca(2+) uptake capacity in tilapia exposed to low Ca(2+) water. Furthermore, the application of cortisol receptor antagonists revealed that cortisol may regulate Ca(2+) uptake through glucocorticoid and/or mineralocorticoid receptor (GR and/or MR) in tilapia. Taken together, the data suggest that cortisol may activate GR and/or MR to execute its hypercalcemic action by stimulating ecac expression in tilapia.

  20. Protein phylogenetic analysis of Ca2+/cation antiporters and insights into their evolution in plants

    Directory of Open Access Journals (Sweden)

    Laura eEmery

    2012-01-01

    Full Text Available Cation transport is a critical process in all organisms and is essential for mineral nutrition, ion stress tolerance, and signal transduction. Transporters that are members of the Ca2+/Cation Antiporter (CaCA superfamily are involved in the transport of Ca2+ and/or other cations using the counter exchange of another ion such as H+ or Na+. The CaCA superfamily has been previously divided into five transporter families: the YRBG, NCX, NCKX, CAX and CCX families, which include the well-characterized Na+/Ca2+ exchanger (NCX and H+/cation exchanger (CAX transporters. To examine the evolution of CaCA transporters within higher plants and the green plant lineage, CaCA genes were identified from the genomes of sequenced flowering plants, a bryophyte, lycophyte, and freshwater and marine algae, and compared with those from non-plant species. We found evidence of the expansion and increased diversity of flowering plant genes within the CAX and CCX families. Genes related to the NCX family are present in land plant though they encode distinct MHX homologs which probably have an altered transport function. In contrast, the NCX and NCKX genes which are absent in land plants have been retained in many species of algae, especially the marine algae, indicating that these organisms may share ‘animal-like’ characteristics of Ca2+ homeostasis and signaling. A group of genes encoding novel CAX-like proteins containing an EF hand domain were identified from plants and selected algae but appeared to be lacking in any other species. Lack of functional data for most of the CaCA proteins make it impossible to reliably predict substrate specificity and function for many of the groups or individual proteins. The abundance and diversity of CaCA genes throughout all branches of life indicates the importance of this class of cation transporter, and that many transporters with novel functions are waiting to be discovered.