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Sample records for multielemental uptake studies

  1. Application of tracer packet technique for multielemental uptake studies on the inorganic ion exchanger zirconium vanadate

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Kamalika; Basu, S.; Ramaswami, A.; Lahiri, Susanta E-mail: slahiri@hp1.saha.ernet.in

    2003-09-01

    The conception of tracer packet was first started with the irradiation of a thick cobalt target with {sup 16}O, {sup 7}Li and {sup 12}C beams, consecutively. This produced carrier-free radiotracers of Mn, Cu, Zn, Ga, Ge, As and Se. These elements are adjacent members in the periodic table and are of nutritional importance. Another 'tracer packet', which was subsequently designed, was of heavy and toxic metals. A gold target irradiated with medium energy {sup 7}Li and {sup 12}C produced {sup 197}Hg, {sup 200}Tl, {sup 200}Pb, {sup 204}Bi, {sup 204}Po. The uptake of these elements has been studied using two different ion exchangers, one of inorganic origin and the other of chelating type.

  2. Evaluation of strontium isotope abundance ratios in combination with multi-elemental analysis as a possible tool to study the geographical origin of ciders

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    Garcia-Ruiz, Silvia [Department of Physical and Analytical Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain); Moldovan, Mariella [Department of Physical and Analytical Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain); Fortunato, Giuseppino [Swiss Federal Laboratories for Materials Testing and Research EMPA, 9014 St. Gallen (Switzerland); Wunderli, Samuel [Swiss Federal Laboratories for Materials Testing and Research EMPA, 9014 St. Gallen (Switzerland); Garcia Alonso, J. Ignacio [Department of Physical and Analytical Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain)]. E-mail: jiga@uniovi.es

    2007-05-02

    In order to evaluate alternative analytical methodologies to study the geographical origin of ciders, both multi-elemental analysis and Sr isotope abundance ratios in combination with multivariate statistical analysis were estimated in 67 samples from England, Switzerland, France and two Spanish regions (Asturias and the Basque Country). A methodology for the precise and accurate determination of the {sup 87}Sr/{sup 86}Sr isotope abundance ratio in ciders by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) was developed. Major elements (Na, K, Ca and Mg) were measured by ICP-AES and minor and trace elements (Li, Be, B, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, W, Tl, Pb, Bi, Th and U) were measured by ICP-MS using a collision cell instrument operated in multitune mode. An analysis of variance (ANOVA test) indicated that group means for B, Cr, Fe, Ni, Cu, Se, Cd, Cs, Ce, W, Pb, Bi and U did not show any significant differences at the 95% confidence level, so these elements were rejected for further statistical analysis. Another group of elements (Li, Be, Sc, Co, Ga, Y, Sn, Sb, La, Tl, Th) was removed from the data set because concentrations were close to the limits of detection for many samples. Therefore, the remaining elements (Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba) together with {sup 87}Sr/{sup 86}Sr isotope abundance ratio were considered for principal component analysis (PCA) and linear discriminant analysis (LDA). Finally, LDA was able to classify correctly 100% of cider samples coming from different Spanish regions, France, England and Switzerland when considering Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba and {sup 87}Sr/{sup 86}Sr isotope abundance ratio as original variables.

  3. A provenance study of iron archaeological artefacts by Inductively Coupled Plasma-Mass Spectrometry multi-elemental analysis

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    Desaulty, Anne-Marie [Laboratoire Pierre Suee CEA - CNRS/UMR 9956 Centre de Saclay, Bat. 637 91191 Gif sur Yvette, Cedex (France); Laboratoire Metallurgies et culture CNRS/UMR 5060 UTBM 90010 Belfort, Cedex (France); Mariet, Clarisse [Laboratoire Pierre Suee CEA - CNRS/UMR 9956 Centre de Saclay, Bat. 637 91191 Gif sur Yvette, Cedex (France)], E-mail: clarisse.mariet@cea.fr; Dillmann, Philippe [Laboratoire Pierre Suee CEA - CNRS/UMR 9956 Centre de Saclay, Bat. 637 91191 Gif sur Yvette, Cedex (France); Laboratoire Metallurgies et culture CNRS/UMR 5060 UTBM 90010 Belfort, Cedex (France); Joron, Jean Louis [Laboratoire Pierre Suee CEA - CNRS/UMR 9956 Centre de Saclay, Bat. 637 91191 Gif sur Yvette, Cedex (France); Institut de Physique du Globe de Paris, Paris VI et Paris VII, 4, place Jussieu 75252 Paris, Cedex 05 (France); Fluzin, Philippe [Laboratoire Metallurgies et culture CNRS/UMR 5060 UTBM 90010 Belfort, Cedex (France)

    2008-11-15

    Raw materials and wastes (i.e. ore, slag and laitier) from ironmaking archaeological sites have been analyzed in order to understand the behavior of the trace elements in the ancient ironmaking processes and to find the significant-most elements to characterize an iron making region. The ICP-MS (Inductively Coupled Plasma Mass Spectrometry) appears to be an excellent technique for this type of studies. The comparison between the ICP-MS results obtained with the Standard Addition method and the INAA (Instrumental Neutron Activation Analyses) results proved that Sc, Co, (Ni), Rb, Cs, Ba, La, Ce, Sm, Eu, Yb, Hf, Th, U contents in the ores, slag and laitiers, and Co and Ni contents in the cast iron can be successfully determined by ICP-MS after wet acid digestion (low detection limits, good sensitivity and precision). By using significant trace element pairs (Yb/Ce, Ce/Th, La/Sc, U/Th, Nb/Y) present in the ores, laitiers and slag, it is possible to discriminate different French ironmaking regions as the Pays de Bray, Lorraine and Pays d'Ouche. These results open the way to further studies on the provenance of iron objects. The comparison between the ICP-MS results obtained with the Standard Calibration Curves method and the INAA results shows that matrices rich in iron, affect the ICP-MS analyses by suppressing the analytes signal. Further studies are necessary to improve understanding matrix effects.

  4. Spin coating nanopatterned multielemental materials via self-assembled nanotemplates.

    Science.gov (United States)

    Xia, Guodong; Jeong, Seong-Jun; Kim, Ji Eun; Kim, Bong Hoon; Koo, Chong-Min; Kim, Sang Ouk

    2009-06-03

    Spin coating of multicomponent precursor solutions was employed in conjunction with block copolymer nanotemplates to fabricate nanopatterned functional multielemental materials. Nanodot and nanowire arrays of several multielemental materials exhibiting optoelectronic and multiferroic properties have been fabricated on various substrates to demonstrate the versatility of our approach. The shape, size and density of nanopatterned multielemental materials can be tuned in a variety of ways. This low cost and large scale solution nanopatterning process without a harsh etching step may offer a new opportunity for development of ultrahigh density device nanostructures.

  5. A study of uranium uptake in plants

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    Kaur, A.; Singh, Surinder; Virk, H.S. (Guru Nanak Dev Univ., Amritsar (India). Dept. of Physics)

    1988-01-01

    A fission track technique has been used to study the uptake of uranium in Tomato Plant. Lexan plastic has been employed as the external detector for recording induced fission tracks due to uranium. The uranium uptake rate is found to increase as the growth proceeds. The uranium concentration is also determined in Phlox, Calendula and Dog Flower, grown under normal conditions. The uranium content is found to vary in different parts of the plants. (author).

  6. Optimized LIBS setup with echelle spectrograph-ICCD system for multi-elemental analysis

    Energy Technology Data Exchange (ETDEWEB)

    Unnikrishnan, V K; Alti, K; Nayak, R; Bernard, R; Kartha, V B; Santhosh, C [Centre for Atomic and Molecular Physics, Manipal University, Manipal (India); Khetarpal, N [Department of Biotechnology, Manipal University, Manipal (India); Gupta, G P; Suri, B M, E-mail: santhosh.cls@manipal.ed [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai (India)

    2010-04-15

    Laser-Induced Breakdown Spectroscopy (LIBS) is well recognized as a promising tool for in situ/remote elemental analysis of environmental, archeological, clinical, and hazardous samples. With the aim of quantifying trace elements in such samples, using LIBS technique, an echelle spectrograph-ICCD system with high sensitivity and good resolution has been assembled. Various important parameters of this system were studied and optimized. Conditions for getting good quality LIBS spectra and signal for multielemental analysis have been achieved, and these are discussed and illustrated in this paper.

  7. Total reflection X-ray fluorescence as a fast multielemental technique for human placenta sample analysis

    Science.gov (United States)

    Marguí, E.; Ricketts, P.; Fletcher, H.; Karydas, A. G.; Migliori, A.; Leani, J. J.; Hidalgo, M.; Queralt, I.; Voutchkov, M.

    2017-04-01

    In the present contribution, benchtop total reflection X-ray fluorescence spectrometry (TXRF) has been evaluated as a cost-effective multielemental analytical technique for human placenta analysis. An easy and rapid sample preparation consisting of suspending 50 mg of sample in 1 mL of a Triton 1% solution in deionized water showed to be the most suitable for this kind of samples. However, for comparison purposes, an acidic microwave acidic digestion procedure was also applied. For both sample treatment methodologies, limits of detection for most elements were in the low mg/kg level. Accurate and precise results were obtained using internal standardization as quantification approach and applying a correction factor to compensate for absorption effects. The correction factor was based on the proportional ratio between the slurry preparation results and those obtained for the analysis of a set of human placenta samples analysed by microwave acidic digestion and ICP-AES analysis. As a study case, the developed TXRF methodology was applied for multielemental analysis (K, Ca, Fe, Cu, Zn, As, Se, Br, Rb and Sr) of several healthy women's placenta samples from two regions in Jamaica.

  8. Study on multielemental speciation analysis of Cr(VI), As(III) and As(V) in water by advanced hyphenated technique HPLC/ICP-DRC-MS. Fast and reliable procedures.

    Science.gov (United States)

    Marcinkowska, Monika; Komorowicz, Izabela; Barałkiewicz, Danuta

    2015-11-01

    Analytical procedures for multielemental speciation analysis of arsenite - As(III), arsenate - As(V) and hexavalent chromium - Cr(VI) in water using high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC/ICP-DRC-MS) hyphenated technique have been developed. A dynamic reaction cell (DRC) for spectral interferences elimination has been involved in the experiment. Application of oxygen and ammonia as reaction gases in the DRC under various conditions has been verified. Optimization of the following chromatographic conditions: mobile phase composition, concentration of particular components, mobile phase pH and flow rate, injection volume and column temperature, has been conducted. Species separation has been carried out on anion-exchange chromatographic column using isocratic elution with: 22 mM (NH4)2HPO4, 25 mM NH4NO3 (for procedure A) and 22 mM (NH4)2HPO4, 65 mM NH4NO3 (for procedure B) as mobile phases. Detection limits (LD) for procedure A were 0.16 µg L(-1), 0.090 µg L(-1), 0.073 µg L(-1), and for procedure B were 0.14 µg L(-1), 0.062 µg L(-1), 0.15 µg L(-1) for As(III), As(V) and Cr(VI), respectively. Linearity was tested at two concentration ranges of: (0.5-10.0) µg L(-1) for procedure A and (5-50) µg L(-1) for procedure B, and showed correlation coefficients for each of the analytes to be above 0.999. Repeatability values obtained for spiked real water samples were in the range of (4.2-7.6)% and (2.0-2.4)% for procedure A and B respectively. Accuracy was calculated based on the analysis of spiked real water samples at three concentration levels. Obtained recoveries were from 94% to 102%.

  9. Multi-elemental profile of some Brazilian make-up products by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dalmazio, Ilza; Menezes, Maria Angela de B.C., E-mail: id@cdtn.b, E-mail: menezes@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Reator e Tecnicas Analiticas. Lab. de Ativacao Neutronica

    2011-07-01

    Recent works have shown that analysis in cosmetics and beauty products from the European and Asian markets indicate the presence of U, Th and rare earths besides other trace elements. Considering these previous findings and health issues, it would be valuable to obtain information on elements in cosmetics available in the Brazilian market. The purpose of this study was to acquire a multi-elemental profile of some Brazilian make-up products of diverse brands. Samples of eye shadow, liquid base, facial concealer, lipstick, and compact face powder were analyzed applying neutron activation analysis, k{sub 0}-standardization method at CDTN/CNEN, using the TRIGA Mark I IPR-R1 research reactor. Concentrations of more than 30 elements in samples are presented and it was found elements included in Brazilian National Health Surveillance Agency prohibitive list, rare earths, Th and U in a minimum of two cosmetic samples. (author)

  10. Multi-elemental profile of some Brazilian make-up products by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dalmazio, Ilza; Menezes, Maria Angela de B.C., E-mail: id@cdtn.b, E-mail: menezes@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Reator e Tecnicas Analiticas. Lab. de Ativacao Neutronica

    2011-07-01

    Recent works have shown that analysis in cosmetics and beauty products from the European and Asian markets indicate the presence of U, Th and rare earths besides other trace elements. Considering these previous findings and health issues, it would be valuable to obtain information on elements in cosmetics available in the Brazilian market. The purpose of this study was to acquire a multi-elemental profile of some Brazilian make-up products of diverse brands. Samples of eye shadow, liquid base, facial concealer, lipstick, and compact face powder were analyzed applying neutron activation analysis, k{sub 0}-standardization method at CDTN/CNEN, using the TRIGA Mark I IPR-R1 research reactor. Concentrations of more than 30 elements in samples are presented and it was found elements included in Brazilian National Health Surveillance Agency prohibitive list, rare earths, Th and U in a minimum of two cosmetic samples. (author)

  11. Micro-scaled high-throughput digestion of plant tissue samples for multi-elemental analysis

    Directory of Open Access Journals (Sweden)

    Husted Søren

    2009-09-01

    Full Text Available Abstract Background Quantitative multi-elemental analysis by inductively coupled plasma (ICP spectrometry depends on a complete digestion of solid samples. However, fast and thorough sample digestion is a challenging analytical task which constitutes a bottleneck in modern multi-elemental analysis. Additional obstacles may be that sample quantities are limited and elemental concentrations low. In such cases, digestion in small volumes with minimum dilution and contamination is required in order to obtain high accuracy data. Results We have developed a micro-scaled microwave digestion procedure and optimized it for accurate elemental profiling of plant materials (1-20 mg dry weight. A commercially available 64-position rotor with 5 ml disposable glass vials, originally designed for microwave-based parallel organic synthesis, was used as a platform for the digestion. The novel micro-scaled method was successfully validated by the use of various certified reference materials (CRM with matrices rich in starch, lipid or protein. When the micro-scaled digestion procedure was applied on single rice grains or small batches of Arabidopsis seeds (1 mg, corresponding to approximately 50 seeds, the obtained elemental profiles closely matched those obtained by conventional analysis using digestion in large volume vessels. Accumulated elemental contents derived from separate analyses of rice grain fractions (aleurone, embryo and endosperm closely matched the total content obtained by analysis of the whole rice grain. Conclusion A high-throughput micro-scaled method has been developed which enables digestion of small quantities of plant samples for subsequent elemental profiling by ICP-spectrometry. The method constitutes a valuable tool for screening of mutants and transformants. In addition, the method facilitates studies of the distribution of essential trace elements between and within plant organs which is relevant for, e.g., breeding programmes aiming at

  12. Multielemental fingerprinting as a tool for authentication of organic wheat, barley, faba bean, and potato.

    Science.gov (United States)

    Laursen, Kristian H; Schjoerring, Jan K; Olesen, Jørgen E; Askegaard, Margrethe; Halekoh, Ulrich; Husted, Søren

    2011-05-11

    The multielemental composition of organic and conventional winter wheat, spring barley, faba bean, and potato was analyzed with inductively coupled plasma-optical emission spectrometry (ICP-OES) and -mass spectrometry (ICP-MS). The crops were cultivated in two years at three geographically different field locations, each accommodating one conventional and two organic cropping systems. The conventional system produced the highest harvest yields for all crops except the nitrogen-fixing faba bean, whereas the dry matter content of each crop was similar across systems. No systematic differences between organic and conventional crops were found in the content of essential plant nutrients when statistically analyzed individually. However, chemometric analysis of multielemental fingerprints comprising up to 14 elements allowed discrimination. The discrimination power was further enhanced by analysis of up to 25 elements derived from semiquantitative ICP-MS. It is concluded that multielemental fingerprinting with semiquantitative ICP-MS and chemometrics has the potential to enable authentication of organic crops.

  13. Multielemental speciation analysis by advanced hyphenated technique - HPLC/ICP-MS: A review.

    Science.gov (United States)

    Marcinkowska, Monika; Barałkiewicz, Danuta

    2016-12-01

    Speciation analysis has become an invaluable tool in human health risk assessment, environmental monitoring or food quality control. Another step is to develop reliable multielemental speciation methodologies, to reduce costs, waste and time needed for the analysis. Separation and detection of species of several elements in a single analytical run can be accomplished by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Our review assembles articles concerning multielemental speciation determination of: As, Se, Cr, Sb, I, Br, Pb, Hg, V, Mo, Te, Tl, Cd and W in environmental, biological, food and clinical samples analyzed with HPLC/ICP-MS. It addresses the procedures in terms of following issues: sample collection and pretreatment, selection of optimal conditions for elements species separation by HPLC and determination using ICP-MS as well as metrological approach. The presented work is the first review article concerning multielemental speciation analysis by advanced hyphenated technique HPLC/ICP-MS.

  14. Evaluation of laser induced breakdown spectroscopy for multielemental determination in soils under sewage sludge application.

    Science.gov (United States)

    Ferreira, Edilene Cristina; Milori, Débora Marcondes Bastos Pereira; Ferreira, Ednaldo José; Dos Santos, Larissa Macedo; Martin-Neto, Ladislau; Nogueira, Ana Rita de Araújo

    2011-07-15

    Laser induced breakdown spectroscopy (LIBS) is an atomic emission spectroscopy technique for simple, direct and clean analysis, with great application potential in environmental sustainability studies. In a single LIBS spectrum it is possible to obtain qualitative information on the sample composition. However, quantitative analysis requires a reliable model for analytical calibration. Multilayer perceptron (MLP), an artificial neural network, is a multivariate technique that is capable of learning to recognize features from examples. Therefore MLP can be used as a calibration model for analytical determinations. Accordingly, the present study proposes to evaluate the traditional linear fit and MLP models for LIBS calibration, in order to attain a quantitative multielemental method for contaminant determination in soil under sewage sludge application. Two sets of samples, both composed of two kinds of soils were used for calibration and validation, respectively. The analyte concentrations in these samples, used as reference, were determined by a reference analytical method using inductively coupled plasma optical emission spectrometry (ICP OES). The LIBS-MLP was compared to a LIBS-linear fit method. The values determined by LIBS-MLP showed lower prediction errors, correlation above 98% with values determined by ICP OES, higher accuracy and precision, lower limits of detection and great application potential in the analysis of different kinds of soils. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Multi-elemental imaging of paraffin-embedded human samples by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Moncayo, S.; Trichard, F.; Busser, B.; Sabatier-Vincent, M.; Pelascini, F.; Pinel, N.; Templier, I.; Charles, J.; Sancey, L.; Motto-Ros, V.

    2017-07-01

    Chemical elements play central roles for physiological homeostasis in human cells, and their dysregulation might lead to a certain number of pathologies. Novel imaging techniques that improve the work of pathologists for tissue analysis and diagnostics are continuously sought. We report the use of Laser-Induced Breakdown Spectroscopy (LIBS) to perform multi-elemental images of human paraffin-embedded skin samples on the entire biopsy scale in a complementary and compatible way with microscope histopathological examination. A specific instrumental configuration is proposed in order to detect most of the elements of medical interest (i.e. P, Al, Mg, Na, Zn, Si, Fe, and Cu). As an example of medical application, we selected and analysed skin biopsies, including healthy skin tissue, cutaneous metastasis of melanoma, Merkel-cell carcinoma and squamous cell carcinoma. Clear distinctions in the distribution of chemical elements are observed from the different samples investigated. This study demonstrates the high complementarity of LIBS elemental imaging with conventional histopathology, opening new opportunities for any medical application involving metals.

  16. Multielemental determinations in chocolate drink powder using multivariate optimization and ICP OES.

    Science.gov (United States)

    Peixoto, Rafaella Regina Alves; Oliveira, Andrea; Cadore, Solange

    2012-08-22

    In this work multivariate experiments were conducted to optimize the operating conditions for inductively coupled plasma optical emission spectrometry (ICP OES) for multielemental determinations in chocolate drink powder. The operating conditions were investigated using a 2(3) central composite design, where the variables studied were radio frequency power, nebulization flow rate, and auxiliary argon flow rate. The effects of these parameters on plasma robustness and on signal to background ratio (SBR) were considered in parallel, allowing the evaluation of robustness and detectability using few and fast experiments to select the best conditions for the determination of the analytes. In this case, the proposed experiments were applied to the optimization of a method aimed at the determination of Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, P, Pb, V, and Zn in chocolate drink powder. The compromise conditions that allowed obtaining a robust and sensitive analytical method were radio frequency power of 1200 W, nebulization flow rate of 0.6 L/min, and auxiliary argon flow rate of 0.3 L/min. Using these conditions, recoveries between 95 and 105% and relative standard deviations lower than 5% were obtained for the majority of the analytes. The proposed method was successfully applied to the analysis of 15 samples of chocolate drink powder. The highest concentrations of metallic species were found in diet and light products.

  17. Multielemental Fingerprinting as a Tool for Authentication of Organic Wheat, Barley, Faba Bean, and Potato

    DEFF Research Database (Denmark)

    Laursen, Kristian Holst; Schjørring, Jan Kofod; Olesen, Jørgen E;

    2011-01-01

    The multielemental composition of organic and conventional winter wheat, spring barley, faba bean, and potato was analyzed with inductively coupled plasma−optical emission spectrometry (ICP-OES) and −mass spectrometry (ICP-MS). The crops were cultivated in two years at three geographically...

  18. Multi-elemental analysis of jet engine lubricating oils and hydraulic fluids and their implication in aircraft air quality incidents.

    Science.gov (United States)

    van Netten, C

    1999-05-07

    The flight crews of aircraft often report symptoms including dizziness, nausea, disorientation, blurred vision and tingling in legs and arms. Many of these incidents have been traced to contamination of cabin air with lubricating oil, as well as hydraulic fluid, constituents. Considering that these air contaminants are often subjected to temperatures in excess of 500 degrees C, a large number of different exposures can be expected. Although the reported symptoms are most consistent with exposures to volatile organic compounds, carbon monoxide, and the organophosphate constituents in these oils and fluids, the involvement of these agents has not been clearly demonstrated. Possible exposure to toxic elements, such as lead, mercury, thallium and others, have not been ruled out. In order to assess the potential of exposure to toxic elements a multi-elemental analysis was done on two hydraulic fluids and three lubricating oils which have been implicated in a number of air quality incidents. A secondary objective was to establish if the multi-elemental concentrations of the fluids tested are different enough to allow such an analysis to be used as a possible method of identifying the source of exposure that might have been present during aircraft air quality incidents. No significant concentrations of toxic elements were identified in any of the oils or hydraulic fluids. The elemental compositions of the samples were different enough to be used for identification purposes and the measurement of only three elements was able to achieve this. Whether these findings have an application, in aircraft air quality incident investigations, needs to be established with further studies.

  19. Phosphate uptake studies of cross-linked chitosan bead materials.

    Science.gov (United States)

    Mahaninia, Mohammad H; Wilson, Lee D

    2017-01-01

    A systematic experimental study is reported that provides a molecular based understanding of cross-linked chitosan beads and their adsorption properties in aqueous solution containing phosphate dianion (HPO4(2-)) species. Synthetically modified chitosan using epichlorohydrin and glutaraldehyde cross-linkers result in surface modified beads with variable hydrophile-lipophile character and tunable HPO4(2-) uptake properties. The kinetic and thermodynamic adsorption properties of cross-linked chitosan beads with HPO4(2-) species were studied in aqueous solution. Complementary structure and physicochemical characterization of chitosan beads via potentiometry, Raman spectroscopy, DSC, and dye adsorption measurements was carried out to establish structure-property relationships. The maximum uptake (Qm) of bead systems with HPO4(2-) at equilibrium was 52.1mgg(-1); whereas, kinetic uptake results for chitosan bead/phosphate systems are relatively rapid (0.111-0.113min(-1)) with an intraparticle diffusion rate-limiting step. The adsorption process follows a multi-step pathway involving inner- and outer-sphere complexes with significant changes in hydration. Phosphate uptake strongly depends on the composition and type of cross-linker used for preparation of chitosan beads. The adsorption isotherms and structural characterization of bead systems illustrate the role of surface charge, hydrophile-lipophile balance, adsorption site accessibility, and hydration properties of the chitosan bead surface. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Multielemental accumulation and its intracellular distribution in tissues of some aquatic birds

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Dong-Ha [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Anan, Yasumi [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Ikemoto, Tokutaka [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)]. E-mail: shinsuke@agr.ehime-u.ac.jp

    2005-11-15

    This study was aimed at determining multielemental concentration and its intracellular distribution in selected tissues of cormorant and waterfowl species. Non-essential elements such as Hg, Tl, Cd, Pb and V in tissues were generally consistent with those in ingested items, indicating the significance of food sources of non-essential metal accumulation in great cormorants and mallards. Great cormorants and four waterfowl species examined reflected natural background levels of toxic metals such as Cd, Hg and Pb as well as some essential elements, indicating no specific metal exposure from local sources. Most of Cu, Zn, Se, Rb, Ag, Cd, Cs, and Hg contents were present in the hepatocytosolic fraction, whereas a large percentage of V and Mo were present in insoluble fraction in great cormorant, mallard, and spot-billed duck. The major role of these subcelluar fractions in elemental regulation accounts for the high percentage contribution of each cellular fraction to the total metal contents. Cadmium and Cu are chiefly sequestered through binding to metallothioneins (MTs) of hepatocytosolic fraction in these three avian species. Both MTs and high-molecular-weight substance (HMWS) for Zn and low-molecular-weight substance (LMWS) for Rb were also involved in their sequestration in cytosolic fractions. Relatively different species-specific cytosolic substances were responsible for varying degrees of Ag, Mn, and Co accumulation. It is worth noting that these intracellular metal levels in birds are closely regulated by metal-associated cellular constituents. Therefore, risk assessment studies of metal accumulation in such wild birds should take intracellular metal distribution and specific cellular constituents into account.

  1. Plant-uptake of uranium: Hydroponic and soil system studies

    Science.gov (United States)

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  2. Mössbauer study of iron uptake in cucumber root

    Science.gov (United States)

    Kovács, K.; Kuzmann, E.; Fodor, F.; Vértes, A.; Kamnev, A. A.

    2005-09-01

    57Fe Mössbauer spectroscopy was used to study the uptake and distribution of iron in the root of cucumber plants grown in iron-deficient modified Hoagland nutrient solution and put into iron-containing solution with 10 μM Fe citrate enriched with 57Fe (90%) only before harvesting. The Mössbauer spectra of the frozen roots exhibited two Fe3+ components with typical average Mössbauer parameters of δ = 0.5 mm s-1, Δ = 0.46 mm s-1 and δ = 0.5 mm s-1, Δ = 1.2 mm s-1 at 78 K and the presence of an Fe2+ doublet, assigned to the ferrous hexaaqua complex. This finding gives a direct evidence for the existence of Fe2+ ions produced via root-associated reduction according to the mechanism proposed for iron uptake for dicotyledonous plants. Monotonous changes in the relative content of the components were found with the time period of iron supply. The Mössbauer results are interpreted in terms of iron uptake and transport through the cell wall and membranes.

  3. Kinetic Uptake Studies of Powdered Materials in Solution

    Directory of Open Access Journals (Sweden)

    Mohamed H. Mohamed

    2015-06-01

    Full Text Available Challenges exist for the study of time dependent sorption processes for heterogeneous systems, especially in the case of dispersed nanomaterials in solvents or solutions because they are not well suited to conventional batch kinetic experiments. In this study, a comparison of batch versus a one-pot setup in two variable configurations was evaluated for the study of uptake kinetics in heterogeneous (solid/solution systems: (i conventional batch method; (ii one-pot system with dispersed adsorbent in solution with a semi-permeable barrier (filter paper or dialysis tubing for in situ sampling; and (iii one-pot system with an adsorbent confined in a semi-permeable barrier (dialysis tubing or filter paper barrier with ex situ sampling. The sorbent systems evaluated herein include several cyclodextrin-based polyurethane materials with two types of phenolic dyes: p-nitrophenol and phenolphthalein. The one-pot kinetics method with in situ (Method ii or ex situ (Method iii sampling described herein offers significant advantages for the study of heterogeneous sorption kinetics of highly dispersed sorbent materials with particles sizes across a range of dimensions from the micron to nanometer scale. The method described herein will contribute positively to the development of advanced studies for heterogeneous sorption processes where an assessment of the relative uptake properties is required at different experimental conditions. The results of this study will be advantageous for the study of nanomaterials with significant benefits over batch kinetic studies for a wide range of heterogeneous sorption processes.

  4. Radiolabeling as a tool to study uptake pathways in plants

    Energy Technology Data Exchange (ETDEWEB)

    Schymura, Stefan; Hildebrand, Heike; Franke, Karsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactive Transport; Fricke, T. [Vita34 BioPlanta, Leipzig (Germany)

    2017-06-01

    The identification of major uptake pathways in plants is an important factor when evaluation the fate of manufactured nanoparticles in the environment and the associated risks. Using different radiolabeling techniques we were able to show a predominantly particulate uptake for CeO{sub 2} nanoparticles (NPs) in contrast to a possible uptake in the form of ionic cerium.

  5. Predictors of hpv vaccination uptake: a longitudinal study among parents

    NARCIS (Netherlands)

    Hofman, R.; Empelen, P. van; Richardus, J.H.; Kok, I.M.C.M. de; Koning, H.J. de; Ballegooijen, M. van; Korfage, I.J.

    2014-01-01

    To assess among parents longitudinal predictors of human papillomavirus (HPV) vaccination uptake for their daughters, random samples of parents were identified via municipal services and sent baseline questionnaires in June 2009 and follow-up questionnaires in November 2011 after their uptake

  6. Calcium uptake in brain synaptosomes: a pharmacologic study

    Energy Technology Data Exchange (ETDEWEB)

    Rampe, D.E.

    1986-01-01

    Pinched-off nerve endings (synaptosomes) from rat and guinea pig brain were used as a model to study Ca/sup 2 +/ entry mechanisms in neuronal tissue. Synaptosomes contain high affinity binding sites for both, 1,4-dihydropyridine Ca/sup 2 +/ channel antagonists, and activators. The thermodynamic characteristics of (/sup 3/H)nitrendipine building in synaptosomes were similar to those seen in both cardiac and smooth muscle preparations. Synaptosomes display two distinct K/sup +/-induced Ca/sup 2 +/ entry mechanisms. These are kinetically distinct with the faster of the two terminating in approx. 1 second while the slower persists for approx. minute. The slow phase uptake process is abolished in Na/sup +/-free media, is sensitive to antagonism by 3,4-dichlorobenzamil and displays a more rapid ontogenic appearance relative to the fast phase. It is likely that the slow phase represents Ca/sup 2 +/ entry via Na/sup +//Ca/sup 2 +/ exchange. The rapid inactivation of the fast phase coupled with its voltage dependence suggest that it represents Ca/sup 2 +/ entry via one or more types of voltage dependent Ca/sup 2 +/ channels. These channels may not be dihydropyridin sensitive since neither nitrendipine nor Bay K 8644 were shown to modulate synaptosomal Ca/sup 2 +/ uptake. The benzodiazepine receptor ligands Ro 5-4864, PK 11195 and diazepam all selectively inhibited fast phase Ca/sup 2 +/ entry relative to slow phase entry. In addition, these compounds altered (/sup 3/H)nitrendipine binding affinity. It is concluded that certain benzodiazepine receptor ligands can interact specifically with voltage dependent Ca/sup 2 +/ channels.

  7. Comparative Studies on Uptake Pathway of Cadmium by Perna viridis

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.

  8. Comparative studies on uptake pathway of cadmium by Perna viridis

    Science.gov (United States)

    Zhanqiang, Fang

    2006-01-01

    Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels' uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.

  9. A qualitative study of uptake of free vitamins in England.

    Science.gov (United States)

    Jessiman, Tricia; Cameron, Ailsa; Wiggins, Meg; Lucas, Patricia J

    2013-08-01

    To identify reasons why eligible families are not accessing free 'Healthy Start' vitamin supplementation (providing vitamins A, C and D) in England. Qualitative study using in-depth interviews. 13 primary care trusts in England. Purposive sample of 15 Healthy Start coordinators, 50 frontline health and children's professionals and 107 parents. Vitamin take-up was low across all research sites, reported as below 10% of eligible beneficiaries for free vitamins. Reasons identified by both parents and professionals included (1) poor accessibility of vitamins, (2) low promotion of the scheme by health professionals, (3) a lack of awareness among eligible families, and (4) low motivation among mothers to take vitamins for themselves during pregnancy or for children under 4 years old. Low uptake rates can be explained by poor accessibility of vitamins and lack of awareness and motivation to take vitamin supplements among eligible families. Universal provision (at least for pregnant women) and better training for health professionals are identified as potential solutions worthy of further research and evaluation.

  10. In vivo methods to study uptake of nanoparticles into the brain.

    Science.gov (United States)

    van Rooy, Inge; Cakir-Tascioglu, Serpil; Hennink, Wim E; Storm, Gert; Schiffelers, Raymond M; Mastrobattista, Enrico

    2011-03-01

    Several in vivo techniques have been developed to study and measure the uptake of CNS compounds into the brain. With these techniques, various parameters can be determined after drug administration, including the blood-to-brain influx constant (K(in)), the permeability-surface area (PS) product, and the brain uptake index (BUI). These techniques have been mostly used for drugs that are expected to enter the brain via transmembrane diffusion or by carrier-mediated transcytosis. Drugs that have limitations in entering the brain via such pathways have been encapsulated in nanoparticles (based on lipids or synthetic polymers) to enhance brain uptake. Nanoparticles are different from CNS compounds in size, composition and uptake mechanisms. This has led to different methods and approaches to study brain uptake in vivo. Here we discuss the techniques generally used to measure nanoparticle uptake in addition to the techniques used for CNS compounds. Techniques include visualization methods, behavioral tests, and quantitative methods.

  11. Microelectrode Studies of Seasonal Oxygen-Uptake in a Coastal Sediment - Role of Molecular-Diffusion

    DEFF Research Database (Denmark)

    RASMUSSEN, H.; JØRGENSEN, BB

    1992-01-01

    Oxygen uptake rates and microdistributions of O2 in sediment of Aarhus Bay, Denmark, were studied over a year. Oxygen uptake was determined in the laboratory by 3 methods: (a) total O2 uptake in closed cores, (b) O2 flux through the diffusive boundary layer and (c) O2 consumption within the oxic...... surface zone. The O2 consumption rates in the oxic surface layer, calculated from (b) and (c) using molecular diffusion coefficients of O2, closely agreed and accounted for 70 % of the total O2 uptake. The O2 uptake rates strongly depended on in situ O2 concentrations in the overlying seawater, which...... in the bay varied from 100 % air saturation during winter to 23 % during summer. The potentially higher O2 respiration during the summer months was counteracted by a lower O2 concentration in the bottom water, which led to a small seasonal variation in O2 uptake. Depth of the oxic sediment zone reached 5...

  12. Digital TV-echelle spectrograph for simultaneous multielemental analysis using microcomputer control

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, J.B.; Case, A.L.

    1980-12-01

    A digital TV-echelle spectrograph with microcomputer control was developed for simultaneous multielemental analysis. The optical system is a commercially available unit originally equipped for film and photomultiplier (single element) readout. The film port was adapted for the intensifier camera. The camera output is digitized and stored in a microcomputer-controlled, 512 x 512 x 12 bit memory and image processor. Multiple spectra over the range of 200 to 800 nm are recorded in a single exposure. Spectra lasting from nanoseconds to seconds are digitized and stored in 0.033 s and displayed on a TV monitor. An inexpensive microcomputer controls the exposure, reads and displays the intensity of predetermined spectral lines, and calculates wavelengths of unknown lines. The digital addresses of unknown lines are determined by superimposing a cursor on the TV display. The microcomputer also writes into memory wavelength fiducial marks for alignment of the TV camera.

  13. Thyroid uptake of /sup 131/I following hippuran renal scintillation camera studies in children

    Energy Technology Data Exchange (ETDEWEB)

    Evans, B.B.; Matthews, A.M.; Woody, H.B.; Meckstroth, G.R.

    1975-08-01

    The thyroid uptake of radioactive iodine after scintillation camera studies using /sup 131/I-labeled hippuran was studied and the radiation dose calculated in 30 euthyroid children with normal renal function. Fifteen children received Lugol's solution which reduced the thyroid uptake and radiation dose significantly.

  14. Predictors of HPV vaccination uptake: A longitudinal study among parents

    NARCIS (Netherlands)

    R. Hofman (Robine); P. van Empelen (Pepijn); J.H. Richardus (Jan Hendrik); I.M.C.M. de Kok (Inge); H.J. de Koning (Harry); M. van Ballegooijen (Marjolein); I.J. Korfage (Ida)

    2014-01-01

    textabstractTo assess among parents longitudinal predictors of human papillomavirus (HPV) vaccination uptake for their daughters, random samples of parents were identified via municipal services and sent baseline questionnaires in June 2009 and follow-up questionnaires in November 2011 after their

  15. Release and uptake of lysosomal enzymes : studied in cultured cells

    NARCIS (Netherlands)

    D.J.J. Halley (Dicky)

    1980-01-01

    textabstractThe purpose of the experimental work described in this thesiswas to investigate some aspects of the release and uptake of lysosomal enzymes. The experiments involved the use of normal human and animal fibroblasts and some other cell types such as hepatocytes and hepatoma cells as sources

  16. Hazardous wastes in aquatic environments: Biological uptake and metabolism studies

    Energy Technology Data Exchange (ETDEWEB)

    Barber, J.; Apblett, A.; Ensley, H. [and others

    1996-05-02

    The projects discussed in this article include the following: the uptake, accumulation, metabolism, toxicity and physiological effects of various environmentally-important contaminants, inorganic and organic, in several wetland species that are interrelated through food webs; and investigation of the potential for developing and linking chemical and biological methods of remediation so as to encapsulate bioaccummulated ions in stable wasteforms such as ceramics and/or zeolites. 24 refs.

  17. Release and uptake of lysosomal enzymes : studied in cultured cells

    OpenAIRE

    1980-01-01

    textabstractThe purpose of the experimental work described in this thesiswas to investigate some aspects of the release and uptake of lysosomal enzymes. The experiments involved the use of normal human and animal fibroblasts and some other cell types such as hepatocytes and hepatoma cells as sources of hydrolytic enzymes, and fibroblasts from patients with lysosomal storage diseases associated with a single lysosomal enzyme deficiency and with "1-cell" disease as recipient cells. In a number ...

  18. A Study of Corrective Feedback and Learner's Uptake in Classroom Interactions

    Directory of Open Access Journals (Sweden)

    Fatemeh Esmaeili

    2014-07-01

    Full Text Available The present study aims to examine corrective feedback and learner uptake in classroom interactions. Inspired by Lyster and Ranta’s corrective feedback framework (1997, this study intends to describe and analyze the patterns of corrective feedback utilized by Iranian teachers, and learners' uptake and the repair of those errors. To this aim, 400 minutes of classroom interaction from three elementary EFL classes which comprised 29 EFL learners were audiotaped and transcribed. The learners were within age range of 16-29 and were native speakers of Turkish language. The teachers were within 26-31 age range and had 3-4 years experience of teaching and hold MA degree in TOEFL. Analysis of data constituted the frequency of six different feedback types used by three teachers, in addition distribution of learners' uptake following each feedback type. The findings indicated that among six corrective feedback types, recast was the most frequent feedback utilized by teachers although it did not lead to high amount of learner uptake. Metalinguistic feedback, elicitation and clarification request led to higher level of uptake. It was also found that explicit feedback was more effective than implicit feedback in promoting learner uptake. Keywords: Corrective Feedback, Learner Uptake, Classroom Interaction, EFL Teachers, EFL Learners

  19. Myocardial uptake in HIV Lymphoma - A case study

    Energy Technology Data Exchange (ETDEWEB)

    Watson, T.N.; Hain, S.F.; Freund, J. [St Vincents Hospital, Sydney, NSW (Australia). Department of Nuclear Medicine

    1997-12-01

    Full text: A 25-year-old male presented to the HIV unit with acute abdominal pain, diarrhoea, malnutrition, dehydration, abdominal distension and haematokzia. CT followed by colonscopic cultures indicated large cell Iymphoma located in the sigmoid. Bone marrow biopsy showed no evidence of Iymphoma. There were no cardiac symptoms. The patient was then referred for a radionuclide gallium scan. The patient was injected with 370 MBq of {sup 67}Ga-citrate. At 72 hours post injection, anterior and posterior sweeps, right and left lateral skull views and a SPECT of the chest were performed. The following day, an anterior abdomen view was collected and a SPECT of the abdomen was performed. Diffuse {sup 67}Ga-citrate accumulation was seen in the myocardium and in the bowel. Radionuclide photopeaks were found to be consistent with gallium. Uptake in the liver was notably decreased, presumably due to concurrent massive blood transfusion for pancytopaenia. Further investigation of the heart was suggested. Owing to the tumour load of the bowel, the patient was immediately treated with chemotherapy without further investigation of the heart. The patient returned for a follow-up {sup 67}Ga-citrate scan three months later. Gallium-67-citrate uptake remained present in the myocardium and the bowel, with both being less intense than in the previous scan. The liver now appears normal. The patient re-presented to the Emergency Department two days post completion of chemotherapy with cardiac tamponade secondary to pericardial effusion, which was drained and cytology showed Iymphoma cells. Lymphoma of the myocardium is not unusual in HIV patients and should not be overlooked or left un investigated as a simple HIV infection

  20. Comparative studies of endotoxin uptake by isolated rat Kupffer and peritoneal cells.

    OpenAIRE

    Fox, E S; Thomas, P; Broitman, S A

    1987-01-01

    The process of uptake of endotoxin by cells of the reticuloendothelial system is of current interest. Rabbit peritoneal macrophages have been used to study macrophage-endotoxin interactions and have suggested a receptor-mediated process. It is generally believed that the site of in vivo endotoxin clearance is the liver and that this clearance involves the Kupffer cell population. In the current report, the uptake characteristics of iodine-125-labeled Salmonella minnesota lipopolysaccharide (L...

  1. Determinants in the uptake of the Human Papillomavirus vaccine: a systematic review based on European studies

    Directory of Open Access Journals (Sweden)

    Victoria eFernández de Casadevante

    2015-06-01

    Full Text Available Background Cervical cancer is the fourth most common cancer affecting women worldwide. Since 2006, two Human Papillomavirus vaccines (HPVV have been licensed to protect women against the virus that causes cervical cancer. However, worldwide coverage remains unequal. Studies from the USA found strong evidence for differences in HPVV uptake by ethnicity and healthcare coverage. As the profile of ethnic groups and the healthcare system in the USA differ from countries in Europe where HPVV is free in most of the countries, we conducted a systematic review in order to analyze the determinants of HPVV uptake in Europe.Methods We performed a systematic Pubmed, Scopus and Science Direct search to find articles published from HPVV availability in European countries until April 2014. No age restriction was applied. We included all studies assessing factors associated with HPVV uptake. Uptake refers to either initiation and/or completion of the three dose vaccination program. Results Out of the 23 eligible studies, 14 were retrospective reviews of data, six were cross-sectional surveys and three were prospective cohort studies. Higher HPVV uptake was associated with ethnic majority populations, higher socio-economic status, regular cervical screening participation by the mother and having received previous childhood vaccinations.Conclusions Since the vaccine is offered for free in most of the European countries, the findings suggest that ethno-cultural and educational factors play an important role when it comes to HPVV uptake. Girls who were undervaccinated had also a lower uptake of standard childhood vaccines and mothers who were less likely to attend cervical cancer screening. This may indicate, that only few parents have specific concerns with HPVV, and that preventive health care should seek ways to target these vulnerable groups.

  2. Application of X-ray fluorescence analytical techniques in phytoremediation and plant biology studies

    Science.gov (United States)

    Nečemer, Marijan; Kump, Peter; Ščančar, Janez; Jaćimović, Radojko; Simčič, Jurij; Pelicon, Primož; Budnar, Miloš; Jeran, Zvonka; Pongrac, Paula; Regvar, Marjana; Vogel-Mikuš, Katarina

    2008-11-01

    Phytoremediation is an emerging technology that employs the use of higher plants for the clean-up of contaminated environments. Progress in the field is however handicapped by limited knowledge of the biological processes involved in plant metal uptake, translocation, tolerance and plant-microbe-soil interactions; therefore a better understanding of the basic biological mechanisms involved in plant/microbe/soil/contaminant interactions would allow further optimization of phytoremediation technologies. In view of the needs of global environmental protection, it is important that in phytoremediation and plant biology studies the analytical procedures for elemental determination in plant tissues and soil should be fast and cheap, with simple sample preparation, and of adequate accuracy and reproducibility. The aim of this study was therefore to present the main characteristics, sample preparation protocols and applications of X-ray fluorescence-based analytical techniques (energy dispersive X-ray fluorescence spectrometry—EDXRF, total reflection X-ray fluorescence spectrometry—TXRF and micro-proton induced X-ray emission—micro-PIXE). Element concentrations in plant leaves from metal polluted and non-polluted sites, as well as standard reference materials, were analyzed by the mentioned techniques, and additionally by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). The results were compared and critically evaluated in order to assess the performance and capability of X-ray fluorescence-based techniques in phytoremediation and plant biology studies. It is the EDXRF, which is recommended as suitable to be used in the analyses of a large number of samples, because it is multi-elemental, requires only simple preparation of sample material, and it is analytically comparable to the most frequently used instrumental chemical techniques. The TXRF is compatible to FAAS in sample preparation, but relative to AAS it is fast

  3. Water uptake efficiency of a maize plant - A simulation case study

    Science.gov (United States)

    Meunier, Félicien; Leitner, Daniel; Bodner, Gernot; Javaux, Mathieu; Schnepf, Andrea

    2014-05-01

    segments based on literature values. This numerical experiment shows significantly different behaviors of the root systems in terms of dynamics of the water uptake, duration of the water stress or cumulative transpiration. The ranking of the maize architectures varied according to the considered drought scenario. The performance of a root system depends on the environment and on its hydraulic architecture suggesting that we always need to take the genotype-environment interaction into account for recommending breeding options. This study also shows that an ideotype must be built for one specific environment: the one we created experienced difficulties to transpire when placed in different conditions it has been designed for. By mathematical simulation we increased the understanding of the most important underlying processes governing water uptake in a root system.

  4. A comparative study on the uptake and translocation of organochlorines by Phragmites australis

    Energy Technology Data Exchange (ETDEWEB)

    San Miguel, Angélique; Ravanel, Patrick [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France); Raveton, Muriel, E-mail: muriel.raveton@ujf-grenoble.fr [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France)

    2013-01-15

    Highlights: ► This study compares uptake/translocation of organochlorine congeners in macrophytes. ► First, root OC uptake was strongly linked with the partitioning/diffusion process. ► With time exposure, bioconcentration increased with OC solubility and volatility. ► Translocation was linked to the combination of water flow and vapor flux transfers. ► The most volatile OCs might be phytovolatilized from foliar surfaces. -- Abstract: Organochlorines (OCs) are persistent chemicals found in various environmental compartments. The differences in the uptake of {sup 14}C-labeled 1,4-dichlorobenzene (DCB), 1,2,4-trichlorobenzene (TCB) and γ-hexachlorocyclohexane (γHCH) by Phragmites australis were investigated under hydroponic conditions. The first step in sorption appears to be correlated with the hydrophobic nature of the compounds, since log-linear correlations were obtained between root concentration factor and partition coefficient (LogK{sub ow}). After 7 days of exposure, plant uptake of DCB, TCB, γHCH was significant with bioconcentration factors reaching 14, 19 and 15, respectively. Afterwards, uptake and translocation were seen to be more complex, with a loss of the simple relationship between uptake and LogK{sub ow}. Linear correlations between the bioconcentration/translocation factors and the physico-chemical properties of OCs were shown, demonstrating that translocation from roots to shoots increases with solubility and volatility of the OCs. This suggests that OC-translocation inside plants might result from the combination of two processes, xylem sap flow and vapor fluxes. {sup 14}C-phytovolatilization was measured and was correlated with the volatility of the compounds; the more volatile OCs being most the likely to be phytovolatilized from foliar surfaces (p = 0.0008). Thus, OC-uptake/translocation appears to proceed at a rate that depends mostly on the OCs hydrophobicity, solubility and volatility.

  5. A simple method for the multi-elemental analysis of organic fertilizer by slurry sampling and total reflection X-ray fluorescence.

    Science.gov (United States)

    Resende, Luciene V; Nascentes, Clésia C

    2016-01-15

    A simple and fast method for the multi-elemental determination of 18 inorganic constituents (P, S, Cl, K, Ca, Ti, Cr, V, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba and Pb) in organic fertilizers employing slurry sampling and total reflection X-ray fluorescence (TXRF) is presented. A 2(3) factorial design with a central point was employed to optimize the slurry sampling procedure. The internal standard and instrumental conditions were optimized by univariate studies. The selectivity of the method to determining Se, As, Pb, Cr, Ni and Cd was assessed. The accuracy was evaluated by the analysis of four standard reference materials (SRM). The recoveries varied from 72% to 114%. For most of the elements, good agreement was achieved between the certified value and the value measured in the SRM. The relative standard deviation (RSD %) ranged from 0.5% to 14%. The evaluated method was applied to the determination of analytes in the press cake of palm, castor, curcas, sunflower, fodder turnip, white lupin, rapeseed and pequi, and their potential to be used as organic fertilizer was evaluated in accordance with Brazilian legislation.

  6. Measuring the actual I-131 thyroid uptake curve with a collar detector system: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Brinks, Peter; Van Gils, Koen; Dickerscheid, Dennis B.M.; Habraken, Jan B.A. [Department of Medical Physics, St. Antonius Hospital, Nieuwegein (Netherlands); Kranenborg, Ellen; Lavalaye, Jules [Department of Nuclear Medicine, St. Antonius Hospital, Nieuwegein (Netherlands)

    2017-06-15

    Radionuclide therapy using I-131 is commonly used for the treatment of benign thyroid diseases. The therapeutic dose to be administered is calculated based on the type of disease, the volume of the thyroid, and the measured uptake percentage. This methodology assumes a similar biological half-life of iodine, whereas in reality a large variation in biological half-life is observed. More knowledge about the actual biological half-life of iodine for individual patients will improve the quantification of the delivered radiation dose during radioiodine therapy and could aid the evaluation of the success of the therapy. In this feasibility study we used a novel measurement device [Collar Therapy Indicator (CoTI)] to measure the uptake curve of patients undergoing I-131 radioiodine therapy. The CoTI device is a light-weight wearable device that contains two independent gamma radiation detectors that are placed in a collar. By comparing results of thyroid uptake measurements with results obtained with a gamma camera, the precision of the system is demonstrated. Additionally, for three patients the uptake curve is measured during 48 h of admission in the hospital. The presented results demonstrate the feasibility of the new measurement device to measure the uptake curve during radioiodine therapy. (orig.)

  7. Comparative studies of endotoxin uptake by isolated rat Kupffer and peritoneal cells.

    Science.gov (United States)

    Fox, E S; Thomas, P; Broitman, S A

    1987-12-01

    The process of uptake of endotoxin by cells of the reticuloendothelial system is of current interest. Rabbit peritoneal macrophages have been used to study macrophage-endotoxin interactions and have suggested a receptor-mediated process. It is generally believed that the site of in vivo endotoxin clearance is the liver and that this clearance involves the Kupffer cell population. In the current report, the uptake characteristics of iodine-125-labeled Salmonella minnesota lipopolysaccharide (LPS) were compared in both isolated rat Kupffer cells and elicited rat peritoneal cells. Both types of cells were isolated from male Sprague-Dawley rats fed a semisynthetic AIN-76 5% saturated-fat diet either by peritoneal lavage for peritoneal cells or by collagenase perfusion followed by purification on a 17.5% metrizamide gradient for Kupffer cells. Hot phenol water-extracted S. minnesota LPS was labeled with iodine by the chloramine-T method following a reaction with methyl-p-hydroxybenzimidate. The in vitro uptake of [125I]LPS by Kupffer cells was unsaturable up to concentrations of 33.33 micrograms/ml, while peritoneal cells became saturated at between 16.67 and 25 micrograms of LPS per ml. Uptake by both types of cells could be inhibited by a 10-fold excess of unlabeled LPS. Kinetic experiments demonstrated that Kupffer cells were unsaturable after 60 min of incubation, while peritoneal cells were saturable after 40 min of incubation. Pretreatment with 75 mM colchicine inhibited uptake by peritoneal cells but not Kupffer cells, while pretreatment with 12 mM 2-deoxyglucose inhibited uptake by Kupffer cells but not peritoneal cells. These results are consistent with a process of receptor-mediated endocytosis for peritoneal cells, while Kupffer cells may internalize endotoxins by absorptive pinocytosis. These results suggest that studies of peritoneal cell-endotoxin interactions do not accurately describe the physiologic process within the liver, the major site for the

  8. A study of bone uptake according to renal function in the whole body bone scan

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong In; Jang, Dong Gun [Dept. of Nuclear Medicine, Dongnam Institute of Radiological and Medical Sciences Cancer Center, Busan (Korea, Republic of); Park, Cheol Woo [Dept. of Radiological Technology Dong-Eui Institute of Technology, Busan (Korea, Republic of)

    2013-12-15

    Whole body bone scan has been used to confirm bone metastasis and follow-up study with radio isotope. However, if the factors related to 99mTc uptake and waiting time for study are inappropriate, it would be image of low quality. The purpose of present study was to investigate correlation between the evaluation index of renal function and uptake of radiopharmaceuticals. The population for this retrospective study consisted of 387 patients who underwent whole body bone scan between June 2012 and December 2012. As a result of quantitative and qualitative analysis, we were able to confirm that GFR of less than normal range and creatinine levels in blood of more than average are more likely to be under the mean uptake rate. As a result of analysis on the indicator affecting soft-tissue and bone uptake, the correlation of all elements was somewhat low. Also there are no statistically significances due to the other parameters we did not deal with. Therefore, further research on additional factors is needed for exact study and improvement of the image quality.

  9. Double pot and double compartment: integrating two approaches to study nutrient uptake by arbuscular mycorrhizal fungi

    NARCIS (Netherlands)

    Cardoso, I.M.; Boddington, C.L.; Janssen, B.H.; Oenema, O.; Kuyper, T.W.

    2004-01-01

    The double compartment technique has been commonly used in studies on nutrient uptake by mycorrhizas whereas the double pot technique has been used to assess the nutritional stress of plants grown in different soils. A combination of the double pot and the double compartment technique was used as a

  10. Análisis multielemental de material foliar por medio de ICP-MS

    Directory of Open Access Journals (Sweden)

    Ana Lorena Alvarado

    2005-01-01

    Full Text Available Se desarrolló un método analítico que permite la aplicación de la técnica híbrida “ICPMS” en el análisis multielemental simultáneo de tejidos foliares. Se optimizó el tratamiento del material foliar, el cual consistió en digerir aproximadamente 0,38 g del tejido foliar, previamente secado y tamizado a 0,5 mm, con HNO3 concentrado; al digerido así obtenido, se le agregó Telurio como estándar interno y luego se diluyó con agua desionizada. La cuantificación se llevó a cabo mediante un ICP-MS ELAN 6000 de PE-Sciex, bajo condiciones instrumentales recomendadas en la literatura y algunas obtenidas mediante procesos de optimización. Los parámetros del desempeño analítico fueron satisfactorios para los siguientes elementos: Al, As, Be, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Tl, V y Zn. Sus límites de detección se calcularon mediante 2 procedimientos diferentes, y oscilaron entre 1 μg l-1 para el Cd y 40 μg l-1 para el P. La exactitud de la metodología propuesta se evaluó determinando los porcentajes de recuperación a 3 niveles de concentración diferentes y empleando además una muestra con contenidos certificados para algunos de los elementos. Los resultados de ambos ensayos incluyeron recuperaciones ubicadas entre un 82% para el Mg y 140% para el Zn. Las sensibilidades promedio se encontraron entre 157 cps (μg l-1-1 para el Be y 12272 cps (μg l-1-1 para el Tl. La precisión del método, expresada mediante la desviación estándar relativa, abarcó desde un 0,8% para el As hasta un 18,6% para el Zn. Se comprobó también que las respuestas obtenidas para cada elemento presentaron un comportamiento lineal en el ámbito de concentraciones de interés.

  11. Effects of blood glucose level on FDG uptake by liver: a FDG-PET/CT study

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Kazuo, E-mail: kkubota@cpost.plala.or.j [Division of Nuclear Medicine, Department of Radiology, National Center for Global Health and Medicine, Tokyo 162-8655 (Japan); Watanabe, Hiroshige; Murata, Yuji [Department of Radiology, Faculty of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan); Yukihiro, Masashi; Ito, Kimiteru; Morooka, Miyako; Minamimoto, Ryogo [Division of Nuclear Medicine, Department of Radiology, National Center for Global Health and Medicine, Tokyo 162-8655 (Japan); Hori, Ai [Department of Epidemiology and International Health, Research Institute, National Center for Global Health and Medicine, Tokyo 162-8655 (Japan); Shibuya, Hitoshi [Department of Radiology, Faculty of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519 (Japan)

    2011-04-15

    In FDG-PET for abdominal malignancy, the liver may be assumed as an internal standard for grading abnormal FDG uptake both in early images and in delayed images. However, physiological variables of FDG uptake by the liver, especially the effects of blood glucose level, have not yet been elucidated. Methods: FDG-PET studies of 70 patients examined at 50 to 70 min after injection (60{+-}10 min: early images) and of 68 patients examined at 80 to 100 min after injection (90{+-}10 min: delayed images) were analyzed for liver FDG uptake. Patients having lesions in the liver, spleen and pancreas; patients having bulk tumor in other areas; and patients early after chemotherapy or radiotherapy were excluded; also, patients with blood glucose level over 125 mg/dl were excluded. Results: Mean standardized uptake value (SUV) of the liver, blood glucose level and sex showed no significant differences between early images and delayed images. However, liver SUV in the delayed image showed a larger variation than that in the early image and showed significant correlation to blood glucose level. The partial correlation coefficient between liver SUV and blood glucose level in the delayed image with adjustment for sex and age was 0.73 (P<.0001). Multivariate regression coefficient (95% confidence interval) of blood glucose was 0.017 (0.013-0.021). Conclusion: Blood glucose level is an important factor affecting the normal liver FDG uptake in nondiabetic patients. In the case of higher glucose level, liver FDG uptake is elevated especially in the delayed image. This may be due to the fact that the liver is the key organ responsible for glucose metabolism through gluconeogenesis and glycogen storage.

  12. Beryllium uptake and related biological effects studied in THP-1 differentiated macrophages.

    Science.gov (United States)

    Ding, Jian; Lin, Lin; Hang, Wei; Yan, Xiaomei

    2009-11-01

    Investigation of cellular uptake of metal compounds is important in understanding metal-related toxicity and diseases. Inhalation of beryllium aerosols can cause chronic beryllium disease, a progressive, granulomatous fibrosis of the lung. Studies in laboratory animals and cultured animal cells indicate that alveolar macrophages take up beryllium compounds and participate in a hypersensitivity immune response to a beryllium-containing antigen. In the present work, human monocyte cell line THP-1 was induced with phorbol myristate acetate to differentiate into a macrophage. This cell with characteristics of human alveolar macrophages was employed to study cellular beryllium uptake and related biological effects. Morphological changes, phagocytosis of fluorescent latex beads, and cell surface CD14 expression were used to verify the successful differentiation of THP-1 monocytes into macrophages. An improved mass spectrometry method for quantitative analysis of intracellular beryllium as opposed to the traditional radioisotopic approach was developed using ICP-MS. The influence of the solubility of beryllium compounds, exposure duration, and beryllium concentration on the incorporation of beryllium was studied. Our data indicated that the uptake of particulate BeO was much more significant than that of soluble BeSO(4), suggesting the major cellular uptake pathway is phagocytosis. Nevertheless, subsequent DAPI nuclear staining and PARP cleavage study indicated that beryllium uptake had a negligible effect on the apoptosis of THP-1 macrophages compared to the unstimulated macrophage control. Meanwhile, no substantial variation of tumour necrosis factor-alpha production was observed for THP-1 macrophages upon beryllium exposure. These data imply alveolar macrophages could have some level of tolerance to beryllium and this may explain why most Be-exposed individuals remain healthy throughout life.

  13. Hydrogen uptake in Zircaloy-2 reactor fuel claddings studied with elastic recoil detection

    Science.gov (United States)

    Rajasekhara, S.; Doyle, B. L.; Enos, D. G.; Clark, B. G.

    2013-04-01

    The recent trend towards a high burn-up discharge spent nuclear fuel necessitates a thorough understanding of hydrogen uptake in Zr-based cladding materials that encapsulate spent nuclear fuel. Although it is challenging to experimentally replicate exact conditions in a nuclear reactor that lead to hydrogen uptake in claddings, in this study we have attempted to understand the kinetics of hydrogen uptake by first electrolytically charging Zircaloy-2 (Zr-2) cladding material for various durations (100 to 2,600 s), and subsequently examining hydrogen ingress with elastic recoil detection (ERD) and transmission electron microscopy (TEM). To understand the influence of irradiation damage defects on hydrogen uptake, an analogous study was performed on ion - irradiated (0.1, 1 and 25 dpa) Zr-2. Analysis of ERD data from the un-irradiated Zr-2 suggests that the growth of the hydride layer is diffusion controlled, and preliminary TEM results support this assertion. In un-irradiated Zr-2, the diffusivity of hydrogen in the hydride phase was found to be approximately 1.1 × 10-11 cm2/s, while the diffusivity in the hydride phase for lightly irradiated (0.1 and 1 dpa) Zr-2 is an order of magnitude lower. Irradiation to 25 dpa results in a hydrogen diffusivity that is comparable to the un-irradiated Zr-2. These results are compared with existing literature on hydrogen transport in Zr - based materials.

  14. Nitrogen uptake and regeneration pathways in the equatorial Pacific: a basin scale modeling study

    Directory of Open Access Journals (Sweden)

    X. Wang

    2009-08-01

    Full Text Available It is well known that most primary production is fueled by regenerated nitrogen in the open ocean. Therefore, studying the nitrogen cycle by focusing on uptake and regeneration pathways would advance our understanding of nitrogen dynamics in the marine ecosystem. Here, we carry out a basin-scale modeling study, by assessing model simulations of nitrate and ammonium, and rates of nitrate uptake, ammonium uptake and regeneration in the equatorial Pacific. Model-data comparisons show that the model is able to reproduce many observed features of nitrate, ammonium, such as the deep ammonium maximum (DAM. The model also reproduces the observed de-coupling of ammonium uptake and regeneration, i.e. regeneration rate greater than uptake rate in the lower euphotic zone. The de-coupling largely explains the observed DAM in the equatorial Pacific Ocean. Our study indicates that zooplankton excretion and remineralization of organic nitrogen play a different role in nitrogen regeneration. Rates of zooplankton excretion vary from <0.01 mmol m−3 d−1 to 0.1 mmol m−3 d−1 in the upper euphotic zone while rates of remineralization fall within a narrow range (0.015–0.025 mmol m−3 d−1. Zooplankton excretion contributes up to 70% of total ammonium regeneration in the euphotic zone, and is largely responsible for the spatial variability of nitrogen regeneration. However, remineralization provides a steady supply of ammonium in the upper ocean, and is a major source of inorganic nitrogen for the oligotrophic regions. Overall, ammonium generation and removal are approximately balanced over the top 150 m in the equatorial Pacific.

  15. Nitrogen uptake and regeneration pathways in the equatorial Pacific: a basin scale modeling study

    Directory of Open Access Journals (Sweden)

    R. Le Borgne

    2009-11-01

    Full Text Available It is well known that most primary production is fueled by regenerated nitrogen in the open ocean. Therefore, studying the nitrogen cycle by focusing on uptake and regeneration pathways would advance our understanding of nitrogen dynamics in the marine ecosystem. Here, we carry out a basin-scale modeling study, by assessing model simulations of nitrate and ammonium, and rates of nitrate uptake, ammonium uptake and regeneration in the equatorial Pacific. Model-data comparisons show that the model is able to reproduce many observed features of nitrate, ammonium, such as the deep ammonium maximum (DAM. The model also reproduces the observed de-coupling of ammonium uptake and regeneration, i.e., regeneration rate greater than uptake rate in the lower euphotic zone. The de-coupling largely explains the observed DAM in the equatorial Pacific Ocean. Our study indicates that zooplankton excretion and remineralization of organic nitrogen play a different role in nitrogen regeneration. Rates of zooplankton excretion vary from <0.01 mmol m−3 d−1 to 0.1 mmol m−3 d−1 in the upper euphotic zone while rates of remineralization fall within a narrow range (0.015–0.025 mmol m−3 d−1 . Zooplankton excretion contributes up to 70% of total ammonium regeneration in the euphotic zone, and is largely responsible for the spatial variability of nitrogen regeneration. However, remineralization provides a steady supply of ammonium in the upper ocean, and is a major source of inorganic nitrogen for the oligotrophic regions. Overall, ammonium generation and removal are approximately balanced over the top 150 m in the equatorial Pacific.

  16. Early changes in [{sup 18}F]FLT uptake after chemotherapy: an experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Dittmann, Helmut; Dohmen, Bernhard Matthias; Bartusek, Gabi; Pritzkow, Maren; Bares, Roland [Department of Nuclear Medicine, Eberhard-Karls-University, Roentgenweg 13, 72076 Tuebingen (Germany); Kehlbach, Rainer [Department of Diagnostic Radiology, Eberhard-Karls-University, Tuebingen (Germany); Sarbia, Mario [Institute of Pathology, Heinrich-Heine-University, Duesseldorf (Germany)

    2002-11-01

    This study evaluated the use of 3'-deoxy-3'-[{sup 18}F]fluorothymidine ([{sup 18}F]FLT) for monitoring of the early effects of anticancer chemotherapy on tumour cell proliferation. Cells derived from human oesophageal squamous cell carcinoma (OSC-1) were grown for 2 days and incubated with cisplatin (CDDP), 5-fluorouracil (5-FU), methotrexate (MTX) or gemcitabine (GEM) for 4 h. Cultures were incubated with drug doses (CDDP: 0.67, 6.7, 67 {mu}M; 5-FU 15.4, 154, 1,540 {mu}M; MTX: 4.4, 44, 440 {mu}M; GEM: 0.0067, 0.067, 0.67 {mu}M) corresponding to approximately 10%-95% proliferation inhibition (MTX: 10%-75%). Treatment was stopped and cells were allowed to recover for 4, 24 or 72 h. [{sup 18}F]FLT was added for 10-180 min. Control cultures were incubated with [{sup 18}F]fluorodeoxyglucose (FDG). Cell counts, viability, clonogenic activity and cell cycle distribution estimated by flow cytometry were used to evaluate the cytotoxic effects of chemotherapy. Strikingly, FLT uptake per 10{sup 5} viable cells was increased seven- to tenfold 24 h after treatment with 5-FU or MTX irrespective of dose. Thus, total FLT uptake per tissue culture exceeded that of controls despite a considerable decrease in overall cell counts due to cytostasis up to 72 h after treatment. 5-FU-treated cells showed accumulation in early S phase (overall S phase: 88% vs 42%). GEM treatment resulted in a more moderate increase in total FLT accumulation, to a maximum of fivefold at the dose close to the IC{sub 50}. In contrast, FLT accumulation was significantly reduced at cytostatic concentrations of CDDP and was still decreasing in a dose-related manner at 72 h despite considerable S phase arrest. With 5-FU or CDDP, the uptake of FDG did not differ significantly from control values 24 h after treatment. These findings demonstrate that tumour cell uptake of FLT - in contrast to that of FDG - reveals specific changes depending on the cytostatic drug used for treatment. The antimetabolites 5

  17. Factors influencing intestinal cadmium uptake in pregnant Bangladeshi women-A prospective cohort study

    Energy Technology Data Exchange (ETDEWEB)

    Kippler, M. [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Goessler, W. [Institut fuer Chemie-Analytische Chemie, Karl-Franzens-Universitaet, Universitaetsplatz 1, 8010 Graz (Austria); Nermell, B. [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Ekstroem, E.C. [Department of Women' s and Children' s Health, International Maternal and Child Health, Uppsala University, SE-751 85 Uppsala (Sweden); Loennerdal, B. [Department of Nutrition, University of California, Davis, CA 95616 (United States); El Arifeen, S. [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), GPO Box 128, Dhaka 100 (Bangladesh); Vahter, M., E-mail: Marie.Vahter@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden)

    2009-10-15

    Experimental studies indicate that zinc (Zn) and calcium (Ca) status, in addition to iron (Fe) status, affect gastrointestinal absorption of cadmium (Cd), an environmental pollutant that is toxic to kidneys, bone and endocrine systems. The aim of this study was to evaluate how various nutritional factors influence the uptake of Cd in women, particularly during pregnancy. The study was carried out in a rural area of Bangladesh, where malnutrition is prevalent and exposure to Cd via food appears elevated. The uptake of Cd was evaluated by associations between erythrocyte Cd concentrations (Ery-Cd), a marker of ongoing Cd exposure, and concentrations of nutritional markers. Blood samples, collected in early pregnancy and 6 months postpartum, were analyzed by inductively coupled plasma mass spectrometry (ICPMS). Ery-Cd varied considerably (range: 0.31-5.4 {mu}g/kg) with a median of 1.1 {mu}g/kg (approximately 0.5 {mu}g/L in whole blood) in early pregnancy. Ery-Cd was associated with erythrocyte manganese (Ery-Mn; positively), plasma ferritin (p-Ft; negatively), and erythrocyte Ca (Ery-Ca; negatively) in decreasing order, indicating common transporters for Cd, Fe and Mn. There was no evidence of Cd uptake via Zn transporters, but the association between Ery-Cd and p-Ft seemed to be dependent on adequate Zn status. On average, Ery-Cd increased significantly by 0.2 {mu}g/kg from early pregnancy to 6 months postpartum, apparently due to up-regulated divalent metal transporter 1 (DMT1). In conclusion, intestinal uptake of Cd appears to be influenced either directly or indirectly by several micronutrients, in particular Fe, Mn and Zn. The negative association with Ca may suggest that Cd inhibits the transport of Ca to blood.

  18. Application of NAA Method to Study Chromium Uptake by Arthrobacter oxydans

    CERN Document Server

    Tsibakhashvili, N Ya; Kalabegishvili, T L; Kirkesali, E I; Frontasyeva, M V; Pomyakushina, E V; Pavlov, S S

    2002-01-01

    To study chromium uptake by Arthrobacter oxydans (Cr(VI)-reducer bacteria isolated from Columbia basalt rocks, USA) instrumental neutron activation analysis method was applied. It was established that chromate accumulation is dose-dependent and it is more intesive in the interval of concentrations of Cr(VI) (10-50 mg/l). At low concentrations of Cr(VI) (up to 50 mg/l) the most intensive formation of Cr(V) was also found (using ESR method). Besides, it was estimated that reduction from Cr(VI) to Cr(V) is faster process than the uptake of Cr(VI). According to ENAA measurements Cr(III), in constant to Cr(VI), is not accumulated in Arthrobacter oxydans cells up to concentration of 200 mg/l. Using epithermal neutron activation analysis the background levels of 17 major, minor and trace elements were determined in Arthrobacter oxydans.

  19. Human benign prostatic hyperplasia in organ culture: studies on iododeoxyuridine uptake

    Energy Technology Data Exchange (ETDEWEB)

    Masters, J.R.; O' Donoghue, E.P.

    1983-01-01

    Prostate tissue architecture and function may be retained in vitro using organ culture. However, the application of the technique is limited due to the lack of simple means for measuring tissue response, for instance to factors controlling cell growth. It is confirmed in this study that measuring the uptake of the radioactive precursor of DNA, 5-(/sup 125/I)-iodo-2'-deoxyuridine, is simple, rapid, and reproducible provided the heterogeneity of benign prostatic hyperplasia (BPH) is taken into account. Factors affecting the reproducibility (numbers of replicate explants and dishes), specificity (removal of unbound radioactivity and uptake into killed tissue), and sensitivity (radioactive concentration and exposure period) of this technique were investigated. A particular advantage of this approach is that histological assessments are made on the same tissue used for biochemical measurements. Furthermore, the method is sufficiently simple to permit serial investigations chronologically concerning factors, such as hormones, controlling BPH cell growth.

  20. Neutron radiography for the study of water uptake in painting canvases and preparation layers

    Energy Technology Data Exchange (ETDEWEB)

    Boon, J.J. [Swiss Institute for Art Research (SIK-ISEA), Zurich (Switzerland); FOM Institute AMOLF, Amsterdam (Netherlands); Hendrickx, R.; Ferreira, E.S.B. [Swiss Institute for Art Research (SIK-ISEA), Zurich (Switzerland); Eijkel, G.; Cerjak, I. [FOM Institute AMOLF, Amsterdam (Netherlands); Kaestner, A. [Paul Scherrer Institut, Neutron Imaging and Activation Group, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland)

    2015-11-15

    Easel paintings on canvas are subjected to alteration mechanisms triggered or accelerated by moisture. For the study of the spatial distribution and kinetics of such interactions, a moisture exposure chamber was designed and built to perform neutron radiography experiments. Multilayered sized and primed canvas samples were prepared for time-resolved experiments in the ICON cold neutron beamline. The first results show that the set-up gives a good contrast and sufficient resolution to visualise the water uptake in the layers of canvas, size and priming. The results allow, for the first time, real-time visualisation of the interaction of water vapour with such layered systems. This offers important new opportunities for relevant, spatially and time-resolved material behaviour studies and opens the way towards numerical modelling of the process. These first results show that cellulose fibres and glue sizing have a much stronger water uptake than the chalk-glue ground. Additionally, it shows that the uptake rate is not uniform throughout the thickness of the sized canvas. With prolonged moisture exposure, a higher amount of water is accumulating at the lower edge of the canvas weave suggesting a decrease in permeability in the sized canvas with increased water content. (orig.)

  1. In vivo hepatic uptake inhibition study of Tc-99m-labeled hepatobiliary agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Meyoung Kon [National Institutes of Health, Bethesda (United States)

    1998-07-01

    We have previously reported that the hepatic uptake of Tc-99m-mercaptoacetyltriglycine (MAG3)-biocytin was not affected by coinjecting bilirubin in mice whereas the uptake of Tc-99m-diisopropyliminodiacetic acid (DISIDA) was inhibited (Kim et al. J Nucl Med, 38 : 50 p, 1997). The aim of this study was to investigate whether the hepatic uptake of Tc-99m-MAG3-biocytin or Tc-99m-DISIDA could be inhibited by biotin and biocytin. The Balb/c mice (female, 20g, n=5-8) were injected i.v. with the hepatobiliary agents alone (15-22 MBq/20-40 {mu}g) or together with inhibitors at two doses (14 and 28 mg/kg). For pharmacokinetic studies, images were acquired at 10-sec intervals for 20 min using a gamma camera equipped with a pin-hole collimator (d= 1 mm), starting immediately after intravenous injection. Pharmacokinetic parameters, peak liver/heart ratio (Rmax) and hepatic half clearance time (HCT), were calculated from liver and heart time-acitivity curves from regions-of-interest. Dynamic images showed rapid hepatic uptake inhibition was characterized by persistent high blood background. These qualitative scintigraphic findings were reflected in the pharmacokinetic parameters. Tc-99m-MAG3-biocytin without inhibitor coinjection showed Rmax of 9.3 and HCT of 383 sec. These parameters did not change significantly when bilirubin or biotin was coinjected, but did change significantly (P<0.05) for biocytin only at the higher dose: 52% decrease in HCT. In contrast, the parameters for Tc-99m-DISIDA (Rmax of 9.2 and HCT of 258 sec) were greatly affected (P<0.01) by biotin (79% decrease in Rman and 2-fold increase in HCT) even at 14 mg/kg concentration. We concluded that Tc-99m-MAG3-biocytin is less sensitive to inhibition by bilirubin, biotin, and biocytin than Tc-99m-DISIDA. Tc-99m-MAG3-biocytin appears to be a promising hepatobiliary imaging agent for hepatic function studies and may also be a useful tool to investigate the hepatic uptake mechanism of biotin derivatives in vivo.

  2. Schools That Make a Difference to Post-Compulsory Uptake of Physical Science Subjects: Some comparative case studies in England

    Science.gov (United States)

    Bennett, Judith; Lubben, Fred; Hampden-Thompson, Gillian

    2013-03-01

    This paper presents the findings of the qualitative component of a combined methods research study that explores a range of individual and school factors that influence the uptake of chemistry and physics in post-compulsory study in England. The first phase involves using the National Pupil Database to provide a sampling frame to identify four matched pairs of high-uptake and low-uptake schools by salient school factors. Case studies of these eight schools indicate that students employ selection strategies related to their career aspirations, their sense of identity and tactics, and their prior experience. The school factors influencing subject choice relate to school management, student support and guidance, and student empowerment. The most notable differences between students in high-uptake and low-uptake schools are that students in high-uptake schools appear to make a proactive choice in relation to career aspirations, rather than a reactive choice on the basis of past experience. Schools with a high uptake offer a diverse science curriculum in the final two years of compulsory study, set higher examination entry requirements for further study and, crucially, provide a range of opportunities for students to interact with the world of work and to gain knowledge and experience of science-related careers.

  3. Further studies on the uptake of persistent organic pollutants (POPs) by polyurethane foam disk passive air samplers

    Science.gov (United States)

    Chaemfa, Chakra; Barber, Jonathan L.; Kim, Kyoung-Sim; Harner, Tom; Jones, Kevin C.

    Passive air samplers (PAS) can be used to monitor semi-volatile organic compounds in the atmosphere. Polyurethane foam (PUF) disks are a popular sampling medium because they have a high retention capacity for such compounds. This paper reports a highly time-resolved uptake study, to derive uptake rate data under field conditions, and investigate the effects of using different foam densities on the uptake rate. PUF disks were deployed alongside an active sampler, for periods of up to 12 weeks. The uptake rates were measured for a range of gas- and particle-bound persistent organic pollutants (polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)), of different properties, to explore whether gas-particle partitioning affected uptake rate. Uptake rates for two different densities of foam (0.021 and 0.035 g cm -3) were not statistically significantly different from each other. Uptake rates of light PCBs averaged ˜6.5 m 3 day -1, somewhat higher than in previous studies; higher wind speeds and lower temperatures in this study are the likely reason for this difference. The study showed: i) the uptake rate of the compound with lowest KOA considered in this study (PCB-28/31) declined in the later weeks, indicating an approach to equilibrium; ii) uptake rates of lighter BDEs and heavier PCBs (compounds of intermediate KOA in this study) remain similar throughout the study period, indicating that they are not approaching equilibrium during the 12-week-study; iii) uptake rates were typically: ˜8 m 3 day -1 for PCB-52; ˜9.5 m 3 day -1 for PCB-95; ˜11 m 3 day -1 for BDE-28 and ˜2 m 3 day -1 BDE-99. The latter compound has an important particle-bound component and this lowers the sampling rate compared to predicted uptake rates for compounds which are in the gas phase only. It is shown that knowledge of gas-particle partitioning is needed to correct for this effect, and to improve predicted uptake rates.

  4. A suggested minimum data list for documenting experimental plant uptake studies

    DEFF Research Database (Denmark)

    Trapp, Stefan; Doucette, W.J.; Fantke, Peter;

    2016-01-01

    Quantifying the plant uptake of organic chemicals is critical for assessing hum an and ecological risks, evaluating plants as biomonitors, predicting phytoremediation effectiveness, and for the continued development and improvement of plant uptake models. Experimental data are commonly expressed...

  5. Study of toxicity and uptake of nanoparticles towards understanding biotic-abiotic interactions

    Science.gov (United States)

    Kosaraju, Karshak

    With the rapid growth in nanotechnology and tremendous applications the engineered nanomaterials (ENs) offer, there is increase in usage of ENs which increases their likelihood of coming in contact with biological systems which include complex beings like humans and other relatively simpler organism like bacteria and other microorganisms. The interaction between the nanomaterials (NMs) and biological systems includes the formation of protein coronas, particle wrapping, intracellular uptake and bio catalytic processes which could have biocompatible or bio adverse outcomes. Understanding these interactions allows the development of predictive relationships between structure and activity that are mainly determined by NM properties such as size, shape, surface chemistry, aggregation, and surface functionality among many others. This understanding will also provide insight towards the design and development of benign nanomaterials. The overarching goal of this dissertation is to understand the influence of the physicochemical characteristics of the NMs and their influence on their uptake and toxicity when they interact with the biological systems (cells and organs). For this purpose, thoroughly characterized NMs will be exposed to a cellular model, A549 cells (alveolar lung epithelial cells), and a mice model (CD-1 mice) through inhalational administration. The effects of NMs on the in vitro and in vivo models will be evaluated by bio- and immuno-chemical methods to understand toxicity, and a combination of analytical spectroscopic and microscopic tools to study uptake. In vivo toxicity assessment will also be performed by using electrocardiogram (ECG) measurements as a tool to study the effects of inhalation of NMs on cardiac response in mice. Through in vivo studies, a novel non-invasive method, Reserve of Refractoriness (RoR), will be introduced as a tool to study cardiotoxicity.

  6. Comparative studies on the uptake and effects of cadmium and zinc on the cellular energy allocation of two freshwater gastropods.

    Science.gov (United States)

    Moolman, L; Van Vuren, J H J; Wepener, V

    2007-11-01

    The uptake and effects of cadmium (Cd) and zinc (Zn) as free metal ions were compared in the freshwater gastropods Melanoides tuberculata and Helisoma duryi. The Langmuir isotherm model was applied to determine the uptake of Cd, Zn, and a mixture of the metals at five different concentrations (Cd: 0.25, 0.51, 0.77, 1.03, 1.29 microM; Zn: 0.17, 0.43, 0.86, 2.17, 4.34 microM). The model gave a good description of metal uptake over a short exposure period (6 h). The gastropods showed interspecies differences in the uptake of Zn. The linear uptake of Cd was similar in these species, although the data did not yield a good fit to the model. No clear Cd/Zn interaction was observed with the mixed metal exposures and both species showed a reduced net uptake for the metals. Cellular energy allocation as a biomarker of exposure provided a measure of the net energy budget (total available energy reserves and total energy consumption). The gastropods were exposed to 0.51 microM Cd, 0.43 microM Zn, and mixture of the metals for a 2-week period. Both species elicited similar decreased net energy budgets following the metal exposures. A combined study on metal uptake and biomarker responses in organisms allows the ability to make interspecies sensitivity comparisons in ecotoxicological studies.

  7. Gadolinium-uptake by aquatic and terrestrial organisms-distribution determined by laser ablation inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Lingott, Jana; Lindner, Uwe; Telgmann, Lena; Esteban-Fernández, Diego; Jakubowski, Norbert; Panne, Ulrich

    2016-02-01

    Gadolinium (Gd) based contrast agents (CA) are used to enhance magnetic resonance imaging. As a consequence of excretion by patients and insufficient elimination in wastewater treatment plants they are detected in high concentrations in surface water. At present, little is known about the uptake of these species by living organisms in aquatic systems. Therefore the uptake of gadolinium containing chelates by plants and animals grown in exposed water or on soil irrigated with exposed water was investigated. For this purpose two types of plants were treated with two different contrast agents. The uptake of the Gd contrast agents was studied by monitoring the elemental distribution with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). This technique allows the multi-elemental analysis of solid samples with high resolution and little sample preparation. The analysis of L. minor showed that the uptake of Gd correlated with the concentration of gadodiamide in the water. The higher the concentration in the exposed water, the larger the Gd signal in the LA-ICP-MS acquired image. Exposure time experiments showed saturation within one day. The L. minor had contact with the CAs through roots and fronds, whereas the L. sativum only showed uptake through the roots. These results show that an external absorption of the CA through the leaves of L. sativum was impossible. All the analyzed parts of the plant showed Gd signal from the CA; the highest being at the main vein of the leaf. It is shown that the CAs can be taken up from plants. Furthermore, the uptake and distribution of Gd in Daphnia magna were shown. The exposure via cultivation medium is followed by Gd signals on the skin and in the area of the intestine, while the uptake via exposed nutrition algae causes the significantly highest Gd intensities in the area of the intestine. Because there are hints of negative effects for human organism these findings are important as they show that Gd based

  8. Knudsen cell and smog chamber study of the heterogeneous uptake of sulfur dioxide on Chinese mineral dust

    Institute of Scientific and Technical Information of China (English)

    Li Zhou; Weigang Wang; Yanbo Gai; Maofa Ge

    2014-01-01

    The heterogeneous uptake processes of sulfur dioxide on two types of Chinese mineral dust (Inner Mongolia desert dust and Xinjiang sierozem) were investigated using both Knudsen cell and smog chamber system.The temperature dependence of the uptake coefficients was studied over a range from 253 to 313 K using the Knudsen cell reactor,the initial uptake coefficients decreased with the increasing of temperature for these two mineral dust samples,whereas the steady state uptake coefficients of the Xinjiang sierozem increased with the temperature increasing,and these temperature dependence functions were obtained for the first time.In the smog chamber experiments at room temperature,the steady state uptake coefficients of SO2 decreased evidently with the increasing of sulfur dioxide initial concentration from 1.72 × 1012 to 6.15 × 1012 mol/cm3.Humid air had effect on the steady state uptake coefficients of SO2 onto Inner Mongolia desert dust.Consequences about the understanding of the uptake processes onto mineral dust samples and the environmental implication were also discussed.

  9. A prospective population study of resting heart rate and peak oxygen uptake (the HUNT Study, Norway.

    Directory of Open Access Journals (Sweden)

    Javaid Nauman

    Full Text Available OBJECTIVES: We assessed the prospective association of resting heart rate (RHR at baseline with peak oxygen uptake (VO(2peak 23 years later, and evaluated whether physical activity (PA could modify this association. BACKGROUND: Both RHR and VO(2peak are strong and independent predictors of cardiovascular morbidity and mortality. However, the association of RHR with VO(2peak and modifying effect of PA have not been prospectively assessed in population studies. METHODS: In 807 men and 810 women free from cardiovascular disease both at baseline (1984-86 and follow-up 23 years later, RHR was recorded at both occasions, and VO(2peak was measured by ergospirometry at follow-up. We used Generalized Linear Models to assess the association of baseline RHR with VO(2peak, and to study combined effects of RHR and self-reported PA on later VO(2peak. RESULTS: There was an inverse association of RHR at baseline with VO(2peak (p<0.01. Men and women with baseline RHR greater than 80 bpm had 4.6 mL.kg(-1.min(-1 (95% confidence interval [CI], 2.8 to 6.3 and 1.4 mL.kg(-1.min(-1 (95% CI, -0.4 to 3.1 lower VO(2peak at follow-up compared with men and women with RHR below 60 bpm at baseline. We found a linear association of change in RHR with VO(2peak (p=0.03, suggesting that a decrease in RHR over time is likely to be beneficial for cardiovascular fitness. Participants with low RHR and high PA at baseline had higher VO(2peak than inactive people with relatively high RHR. However, among participants with relatively high RHR and high PA at baseline, VO(2peak was similar to inactive people with relatively low RHR. CONCLUSION: RHR is an important predictor of VO(2peak, and serial assessments of RHR may provide useful and inexpensive information on cardiovascular fitness. The results suggest that high levels of PA may compensate for the lower VO(2peak associated with a high RHR.

  10. Swelling, ion uptake and biodegradation studies of PE film modified through radiation induced graft copolymerization

    Science.gov (United States)

    Kaur, Inderjeet; Gupta, Nitika; Kumari, Vandna

    2011-09-01

    An attempt to develop biodegradable polyethylene film grafting of mixture of hydrophilic monomers methacrylic acid (MAAc) and acrylamide (AAm) onto PE film has been carried out by preirradiation method using benzoyl peroxide as the radical initiator. Since ether linkages are susceptible to easy cleavage during degradation process, PE film was irradiated before the grafting reactions by γ-rays to introduce peroxidic linkages (PE-OO-PE) that offer sites for grafting. The effect of irradiation dose, monomer concentration, initiator concentration, temperature, time and amount of water on the grafting percent was determined. Maximum percentage of grafting of binary mixture (MAAc+AAm), (1792%) was obtained at a total concentration of binary monomer mixture=204.6×10 -2 mol/L ([MAAc]=176.5×10 -2 mol/L, [AAm]=28.1×10 -2 mol/L), [BPO]=8.3×10 -2 mol/L at 100 °C in 70 min. The grafted PE film was characterized by the Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopic (SEM) methods. Some selective properties of grafted films such as swelling studies, ion uptake and biodegradation studies have been investigated. The grafted films show good swelling in water, ion uptake studies shows promising results for desalination of brackish water and the soil burial test shows that PE film grafted with binary monomer mixture degrades up to 47% within 50 days.

  11. Study of uptake of zinc into blood from a Nigerian diet using INAA

    Science.gov (United States)

    Ojo, J. O.; Osoniyi, R. O.; Aboderin, A. O.

    2003-01-01

    This work describes our on-going investigations on the study of uptake of zinc from dietary intakes, into blood. The aim is to evaluate the possibility of successful application of dietary zinc therapy in the management of Sickle Cell Anaemia (SCA). Seven adult subjects were involved in the current study. After the ingestion of an experimental diet, blood samples were withdrawn from the subjects at various time intervals. The blood samples were further separated into erythrocytes and plasma. Both blood components and the ingested diet were analysed by instrumental neutron activation analysis (INAA) for zinc. Significant increases in the levels of plasma zinc were recorded in the subjects within 2 hours after the ingestion of the diet and were sustained till about the fourth hour. We were not able to detect significant uptake of zinc in the erythrocytes. Either the levels of ingested zinc were too low or there were inhibitions of the absorption by the diet. Better response is expected in SCA patients since they are known to be frequently zinc-deficient.

  12. A Priori Attitudes Predict Amniocentesis Uptake in Women of Advanced Maternal Age: A Pilot Study.

    Science.gov (United States)

    Grinshpun-Cohen, Julia; Miron-Shatz, Talya; Rhee-Morris, Laila; Briscoe, Barbara; Pras, Elon; Towner, Dena

    2015-01-01

    Amniocentesis is an invasive procedure performed during pregnancy to determine, among other things, whether the fetus has Down syndrome. It is often preceded by screening, which gives a probabilistic risk assessment. Thus, ample information is conveyed to women with the goal to inform their decisions. This study examined the factors that predict amniocentesis uptake among pregnant women of advanced maternal age (older than 35 years old at the time of childbirth). Participants filled out a questionnaire regarding risk estimates, demographics, and attitudes on screening and pregnancy termination before their first genetic counseling appointment and were followed up to 24 weeks of gestation. Findings show that women's decisions are not always informed by screening results or having a medical indication. Psychological factors measured at the beginning of pregnancy: amniocentesis risk tolerance, pregnancy termination tolerance, and age risk perception affected amniocentesis uptake. Although most women thought that screening for Down syndrome risk would inform their decision, they later stated other reasons for screening, such as preparing for the possibility of a child with special needs. Findings suggest that women's decisions regarding amniocentesis are driven not only by medical factors, but also by a priori attitudes. The authors believe that these should be addressed in the dialogue on women's informed use of prenatal tests.

  13. Analytical performance of benchtop total reflection X-ray fluorescence instrumentation for multielemental analysis of wine samples

    Science.gov (United States)

    Dalipi, Rogerta; Marguí, Eva; Borgese, Laura; Bilo, Fabjola; Depero, Laura E.

    2016-06-01

    Recent technological improvements have led to a widespread adoption of benchtop total reflection X-ray fluorescence systems (TXRF) for analysis of liquid samples. However, benchtop TXRF systems usually present limited sensitivity compared with high-scale instrumentation which can restrict its application in some fields. The aim of the present work was to evaluate and compare the analytical capabilities of two TXRF systems, equipped with low power Mo and W target X-ray tubes, for multielemental analysis of wine samples. Using the Mo-TXRF system, the detection limits for most elements were one order of magnitude lower than those attained using the W-TXRF system. For the detection of high Z elements like Cd and Ag, however, W-TXRF remains a very good option due to the possibility of K-Lines detection. Accuracy and precision of the obtained results have been evaluated analyzing spiked real wine samples and comparing the TXRF results with those obtained by inductively coupled plasma emission spectroscopy (ICP-OES). In general, good agreement was obtained between ICP-OES and TXRF results for the analysis of both red and white wine samples except for light elements (i.e., K) which TXRF concentrations were underestimated. However, a further achievement of analytical quality of TXRF results can be achieved if wine analysis is performed after dilution of the sample with de-ionized water.

  14. Identification and preliminary SAR studies of (+)-Geodin as a glucose uptake stimulator for rat adipocytes.

    Science.gov (United States)

    Sato, Seiichi; Okusa, Noriyuki; Ogawa, Akiyo; Ikenoue, Takao; Seki, Tetsuya; Tsuji, Takashi

    2005-09-01

    (+)-Geodin (1) was isolated from Penicillium glabrum AJ117540 with activity that stimulates glucose uptake by rat adipocytes. Unlike insulin it is active in the presence of wortmannin. Dihydrogeodin (2) and sulochrin (3) which are the precursors of (+)-geodin biosynthesis were also isolated from the same fungus. Preliminary SAR studies of 1 showed some analogues had enhanced activity. Especially, the activities of racemic geodin and dibromo analogue (7a) were comparable to that of the natural product. Geodin (1), a known fungal metabolite, was isolated from Penicillium glabrum AJ117540 as an active substance (Fig. 1). Dihydrogeodin (2) and sulochrin (3), the precursors of 1, were also isolated from the same fungal extract. In this study, preliminary mechanistic insight and SAR are reported.

  15. Laboratory Studies of the Heterogeneous Uptake of Methane on Martian Soil Analogs: Determination of Upper Limits of Reactivity

    Science.gov (United States)

    Gough, R. V.; Hatch, C. D.; Tolbert, M. A.

    2007-12-01

    In order to constrain possible methane sources on Mars, it is necessary to understand the type and magnitude of all possible methane sinks. We have performed laboratory experiments to determine the importance of heterogeneous uptake of methane on mineral surfaces analogous to Martian surface material. The uptake of methane on sodium montmorillonite and Mars soil simulant JSC-1 (a palagonite) was studied using a Knusden cell flow reactor capable of achieving Martian temperature, pressure and relative humidity conditions. A quadrupole mass spectrometer was used to detect any decrease in methane flow due to heterogeneous uptake and infrared spectroscopy was used to detect any adsorbed species on the particles. Experiments were performed under Martian temperatures (from 195 to 215 K), and under both dry conditions and 45% RH. As montmorillonite clay possesses unique swelling properties in the presence of water vapor, experiments were performed in which the clay was simultaneously exposed to water and methane, and also experiments in which the clay was equilibrated with water vapor prior to methane exposure. We found no methane uptake relative to an unreactive blank Si wafer on any of the Martian soil analogs studied under any conditions. These negative results place upper limits on the heterogeneous reactivity of methane on the Martian surface. We have determined that the initial uptake coefficient of methane on palagonite is less than 3.66×10-10 (±1.41×10-11) and the initial uptake coefficient, γ0, of methane on montmorillonite is less than 7.52×10-10 (±2.56×10-11). These studies demonstrate methane uptake by mineral surfaces is not expected to be a significant methane sink, as the process likely occurs on a time scale much longer than photolysis.

  16. A Preliminary Study of Europium Uptake by Yeast Cells. The Case of Kluveromyces Marxianus

    Science.gov (United States)

    Anagnostopoulos, V.; Symeopoulos, B.

    2008-08-01

    The objective of the present work is an exploration of a cost effective recovery of lanthanides, either for minimizing the industrial processes losses, or for reasons related to Radioactive Waste Management. Specifically, the uptake of europium from aqueous solutions by Kluveromyces marxianus cells was studied. Moreover, this biotechnological approach turns out to be environmental friendly, considering that cells of Kluveromyces marxianus are readily available as wastes from food fermentation industries. Europium [152Eu+154Eu]-labelled solutions were used providing better accuracy and reproducibility of measurements, mainly in low concentration range. The effect of pH, contact time and europium initial concentration were investigated. Adsorption data were fitted to Langmuir and Freundlich sorption models and Scatchard plots were used to reveal the existence of at least two types of binding sites.

  17. Feasibility Study of the Permeability and Uptake of Mesoporous Silica Nanoparticles across the Blood-Brain Barrier.

    Science.gov (United States)

    Baghirov, Habib; Karaman, Didem; Viitala, Tapani; Duchanoy, Alain; Lou, Yan-Ru; Mamaeva, Veronika; Pryazhnikov, Evgeny; Khiroug, Leonard; de Lange Davies, Catharina; Sahlgren, Cecilia; Rosenholm, Jessica M

    2016-01-01

    Drug delivery into the brain is impeded by the blood-brain-barrier (BBB) that filters out the vast majority of drugs after systemic administration. In this work, we assessed the transport, uptake and cytotoxicity of promising drug nanocarriers, mesoporous silica nanoparticles (MSNs), in in vitro models of the BBB. RBE4 rat brain endothelial cells and Madin-Darby canine kidney epithelial cells, strain II, were used as BBB models. We studied spherical and rod-shaped MSNs with the following modifications: bare MSNs and MSNs coated with a poly(ethylene glycol)-poly(ethylene imine) (PEG-PEI) block copolymer. In transport studies, MSNs showed low permeability, whereas the results of the cellular uptake studies suggest robust uptake of PEG-PEI-coated MSNs. None of the MSNs showed significant toxic effects in the cell viability studies. While the shape effect was detectable but small, especially in the real-time surface plasmon resonance measurements, coating with PEG-PEI copolymers clearly facilitated the uptake of MSNs. Finally, we evaluated the in vivo detectability of one of the best candidates, i.e. the copolymer-coated rod-shaped MSNs, by two-photon in vivo imaging in the brain vasculature. The particles were clearly detectable after intravenous injection and caused no damage to the BBB. Thus, when properly designed, the uptake of MSNs could potentially be utilized for the delivery of drugs into the brain via transcellular transport.

  18. Multielemental analysis of 18 essential and toxic elements in amniotic fluid samples by ICP-MS: Full procedure validation and estimation of measurement uncertainty.

    Science.gov (United States)

    Markiewicz, B; Sajnóg, A; Lorenc, W; Hanć, A; Komorowicz, I; Suliburska, J; Kocyłowski, R; Barałkiewicz, D

    2017-11-01

    Amniotic fluid is the substantial factor in the development of an embryo and fetus due to the fact that water and solutes contained in it penetrate the fetal membranes in an hydrostatic and osmotic way as well as being swallowed by the fetus. Elemental composition of amniotic fluid influences the growth and health of the fetus, therefore, an analysis of amniotic fluid is important because the results would indicate abnormal levels of minerals or toxic elements. Inductively coupled plasma mass spectroscopy (ICP-MS) is often used for determination of trace and ultra-trace level elements in a wide range of matrices including biological samples because of its unique analytical capabilities. In the case of trace and ultra-trace level analysis detailed characteristics of analytical procedure as well as properties of the analytical result are particularly important. The purpose of this study was to develop a new analytical procedure for multielemental analysis of 18 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Mg, Mn, Ni, Pb, Sb, Se, Sr, U, V and Zn) in amniotic fluid samples using ICP-MS. Dynamic reaction cell (DRC) with two reaction gases, ammonia and oxygen, was involved in the experiment to eliminate spectral interferences. Detailed validation was conducted using 3 certified reference mterials (CRMs) and real amniotic fluid samples collected from patients. Repeatability for all analyzed analytes was found to range from 0.70% to 8.0% and for intermediate precision results varied from 1.3% to 15%. Trueness expressed as recovery ranged from 80% to 125%. Traceability was assured through the analyses of CRMs. Uncertainty of the results was also evaluated using single-laboratory validation approach. The obtained expanded uncertainty (U) results for CRMs, expressed as a percentage of the concentration of an analyte, were found to be between 8.3% for V and 45% for Cd. Standard uncertainty of the precision was found to have a greater influence on the combined standard uncertainty

  19. Studies on the T sub 3 suppression test with reference to the thyrodial sup 123 I uptake in Graves' disease; Comparison of 24-hour and 3-hour uptake

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Takahiko; Kobayashi, Isao; Yamaguchi, Yoshiyuki; Iwashita, Akira; Inukai, Toshihiko; Ohshima, Kihachi; Shimomura, Yohnosuke; Kobayashi, Setsuo (Gunma Univ., Maebashi (Japan). School of Medicine)

    1990-06-01

    Eighty-three patients with Graves' disease had been treated with methylmercaptoimidazole (MMI). They were prescribed a maintenance dose of antithyroid drug (MMI, 5 mg/day) at the time of a T{sub 3} suppression test. The 3-hour and 24-hour thyroidal {sup 123}I uptake after T{sub 3} administration (75 {mu}g/day, 2 weeks) were measured (post T{sub 3} uptake). In 38 patients whose post T{sub 3} uptake was below 35% in post T{sub 3} 24-hour uptake, treatment was stopped. The T{sub 3} suppression test was then repeated 1 and 3 months later. During a one-year follow up, 26 remained well, while 12 relapsed within 6 to 12 months. We have observed a good correlation between 3-hour uptake and 24-hour uptake of {sup 123}I after T{sub 3} administration (r=0.847, p<0.001). In 38 patients who showed positive T{sub 3} suppression, most patients with MMI withdrawal produced a marked overshoot of post T{sub 3} 3-hour and 24-hour uptake at one month. Retrospective analysis indicated that there was no significant difference in circulating thyroid hormone levels between remission and relapse groups. The present study provides evidence that 3-hour uptake values are able to be substituted for 24-hour uptake values during a T{sub 3} suppression test. In addition, overshoot of thyroidal uptake after antithyroid drug withdrawal was observed in 3-hour values, similar to 24-hour values. (author).

  20. Using measured soil water contents to estimate evapotranspiration and root water uptake profiles - a comparative study

    Science.gov (United States)

    Guderle, M.; Hildebrandt, A.

    2015-01-01

    Understanding the role of plants in soil water relations, and thus ecosystem functioning, requires information about root water uptake. We evaluated four different complex water balance methods to estimate sink term patterns and evapotranspiration directly from soil moisture measurements. We tested four methods. The first two take the difference between two measurement intervals as evapotranspiration, thus neglecting vertical flow. The third uses regression on the soil water content time series and differences between day and night to account for vertical flow. The fourth accounts for vertical flow using a numerical model and iteratively solves for the sink term. None of these methods requires any a priori information of root distribution parameters or evapotranspiration, which is an advantage compared to common root water uptake models. To test the methods, a synthetic experiment with numerical simulations for a grassland ecosystem was conducted. Additionally, the time series were perturbed to simulate common sensor errors, like those due to measurement precision and inaccurate sensor calibration. We tested each method for a range of measurement frequencies and applied performance criteria to evaluate the suitability of each method. In general, we show that methods accounting for vertical flow predict evapotranspiration and the sink term distribution more accurately than the simpler approaches. Under consideration of possible measurement uncertainties, the method based on regression and differentiating between day and night cycles leads to the best and most robust estimation of sink term patterns. It is thus an alternative to more complex inverse numerical methods. This study demonstrates that highly resolved (temporally and spatially) soil water content measurements may be used to estimate the sink term profiles when the appropriate approach is used.

  1. Primary care patient experience and cancer screening uptake among women: an exploratory cross-sectional study in a Japanese population.

    Science.gov (United States)

    Aoki, Takuya; Inoue, Machiko

    2017-01-01

    Patient experience and clinical quality, which are represented by preventive care measures such as cancer screening, are both widely used for the evaluation of primary care quality. The aim of this study was to examine the association between patient experience and cancer screening uptake among women in a Japanese population. We conducted a cross-sectional mail survey. The questionnaire was sent to 1000 adult female residents randomly selected from a basic resident register in Yugawara town, Kanagawa, Japan. We assessed patient experience of primary care using a Japanese version of Primary Care Assessment Tool (JPCAT) and uptake of breast and cervical cancer screening. The overall response rate was 46.5%. Data were analyzed for 190 female participants aged 21-74 years who had a usual source of primary care. Multivariate logistic regression analyses revealed that the JPCAT total score was significantly associated with uptake of breast cancer screening [odds ratio (OR) per 1 standard deviation increase = 1.63; 95% CI 1.11-2.41], but not with uptake of cervical cancer screening (OR per 1 standard deviation increase = 1.47; 95% CI 0.97-2.24). Patient experience of primary care was associated with uptake of breast cancer screening among Japanese women. The results of our study might support the argument that patient experience of primary care and the clinical process of preventive care, such as breast cancer screening, are linked.

  2. Preliminary PET/CT Study of 18F-FDG Uptake in Cervical and Supraclavicular Brown Adipose Tissue

    Institute of Scientific and Technical Information of China (English)

    Na Fang; Wei Ding; Yanli Wang; Xinjian Cui; Lei Zeng; Lili Ma; Xiumei Zhao; Wei Zhao; Qing Wang; Shan Gao

    2008-01-01

    OBJECTIVE The clinical use of PET/CT in oncology has led to the realization that 18F-FDG uptake in brown adipose tissue (BAT)can be a common cause of potentially misleading false-positive PET scans.The goal of this study was to study 18F-FDG uptake in cervical and supraclavicular regions and its characteristics with PET/CT.METHODS All the PET/CT scans obtained at our institution from July 2007 to January 2008 were retrospectively reviewed for increased 18F-FDG uptake in BAT.The cases in which increased 18F-FDG in cervical and supraclavicular regions was not localized to a soft-tissue mass or lymph node or muscle on the CT images,were included in this study.The following features were recorded:body weight,body mass index (BMI) and maximal standardized uptake value (SUVmax).In these selected patients,the BAT uptake in other area of the body was also recorded.RESULTS PET/CT scans were obtained in 457 patients (259 males and 198 females).In all of the scans,cervical and supraclavicular BAT uptake was observed in 12 patients (2 males and 10 females) and was typically bilateral,symmetric and intense.The range of the SUVmax was 3.6~12.82 (mean 6.9 ± 2.6).BAT uptake was more common in females than in males,showing a significant difference (P = 0.004).Although 18F-FDG uptake in BAT occurred more often in underweight patients with low BMI,there was no difference in the body weight (P = 0.607) or BMI (P =0.491) of these patients with hypermetabolic BAT compared with controls.CONCLUSION Hypermetabolic BAT uptake can be localized in cervical and supraclavicular regions with it occurring more commonly in females compared to males.Knowledge of this potential pitfall with PET/CT is important in improving diagnostic interpretation and accurate staging.

  3. Inhibitory action of sphingosine, sphinganine and dexamethasone on glucose uptake: Studies with hydrogen peroxide and phorbol ester

    Energy Technology Data Exchange (ETDEWEB)

    Murray, D.K.; Hill, M.E.; Nelson, D.H. (Univ. of Utah School of Medicine, Salt Lake City (USA))

    1990-01-01

    The mechanism of the inhibitory action of glucocorticoids on glucose uptake is incompletely understood. Treatment with corticosteriods of cells in which glucose uptake is stimulated at insulin postbinding and postreceptor sites may clarify the site of the steroid inhibitory action. Hydrogen peroxide, which has been shown to stimulate the insulin receptor tyrosine kinase, and phorbol myristate acetate (PMA) which stimulates protein kinase C were, therefore, used as stimulators of glucose transport in this study. These studies demonstrate that dexamethasone and the sphingoid bases, sphinganine and sphingosine, inhibit glucose uptake that has been stimulated at either the receptor kinase or protein kinase C level in both 3T3-L1 and 3T3-C2 cells. These data confirm glucocorticoid inhibitory action at a post binding level and support the suggestion that some corticosteriod inhibitory effects may be mediated by an action on sphingolipid metabolism.

  4. Uptake of Photosensitizer 2-Devinyl-2-(1-methoxylethyl Chlorin f in Human Breast Cancer Cells: A Diffusion Kinetics Study

    Directory of Open Access Journals (Sweden)

    Ping Chen

    2012-01-01

    Full Text Available The kinetics of photosensitizer 2-devinyl-2-(1-methoxylethyl chlorin f (CPD4 uptake in MCF-7 human breast cancer cells is described by a diffusion kinetics model and experimentally investigated using laser scanning confocal microscopy (LSCM. CPD4 permeated into MCF-7 cells with increasing incubation time, which was followed by its binding to cell organelles. Subcellular distribution study revealed that CPD4 was primarily localized on the mitochondria and membranes, supporting that the mode of transmembrane transport was diffusion. A kinetics model describing CPD4 passing through the plasma membrane of MCF-7 cells was proposed based on Fick's first law of diffusion. The kinetics of cellular uptake of CPD4 was studied by three-dimensional LSCM. By fitting the experimental data using the above model, important cellular uptake and distribution parameters were obtained, which are of clinical significance in photodynamic therapy.

  5. Swelling, ion uptake and biodegradation studies of PE film modified through radiation induced graft copolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Inderjeet, E-mail: ij_kaur@hotmail.com [Department Chemistry, HPU Shimla 171005 (India); Gupta, Nitika; Kumari, Vandna [Department Chemistry, HPU Shimla 171005 (India)

    2011-09-15

    An attempt to develop biodegradable polyethylene film grafting of mixture of hydrophilic monomers methacrylic acid (MAAc) and acrylamide (AAm) onto PE film has been carried out by preirradiation method using benzoyl peroxide as the radical initiator. Since ether linkages are susceptible to easy cleavage during degradation process, PE film was irradiated before the grafting reactions by {gamma}-rays to introduce peroxidic linkages (PE-OO-PE) that offer sites for grafting. The effect of irradiation dose, monomer concentration, initiator concentration, temperature, time and amount of water on the grafting percent was determined. Maximum percentage of grafting of binary mixture (MAAc+AAm), (1792%) was obtained at a total concentration of binary monomer mixture=204.6x10{sup -2} mol/L ([MAAc]=176.5x10{sup -2} mol/L, [AAm]=28.1x10{sup -2} mol/L), [BPO]=8.3x10{sup -2} mol/L at 100 deg. C in 70 min. The grafted PE film was characterized by the Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopic (SEM) methods. Some selective properties of grafted films such as swelling studies, ion uptake and biodegradation studies have been investigated. The grafted films show good swelling in water, ion uptake studies shows promising results for desalination of brackish water and the soil burial test shows that PE film grafted with binary monomer mixture degrades up to 47% within 50 days. - Highlights: > Binary mixture of methacrylic acid (MAAc) and acrylamide (AAm) onto PE film by preirradiation method was carried out. > Graft copolymers of MAAc+AAm and PE film were characterized by FTIR, TGA and SEM studies and was found to be thermally stable. > Grafting of MAAc+AAm improved swelling behavior giving maximum swelling (485.71%) in water as against PE with 0% swelling. > The grafted PE-g-poly (MAAc-co-AAm) behaves as an excellent material for ion separation. > Biodegradation studies by soil burial test showed 47.19% of

  6. Understanding low colorectal cancer screening uptake in South Asian faith communities in England--a qualitative study.

    Science.gov (United States)

    Palmer, Cecily K; Thomas, Mary C; McGregor, Lesley M; von Wagner, Christian; Raine, Rosalind

    2015-10-01

    Colorectal cancer screening uptake within the South Asian population in England is approximately half that of the general population (33 % vs 61 %), and varies by Muslim (31.9 %), Sikh (34.6 %) and Hindu (43.7 %) faith background. This study sought to explore reasons for low uptake of CRC screening in South Asian communities and for the variability of low uptake between three faith communities; and to identify strategies by which uptake might be improved. We interviewed 16 'key informants' representing communities from the three largest South Asian faith backgrounds (Islam, Hinduism and Sikhism) in London, England. Reasons for low colorectal cancer screening uptake were overwhelmingly shared across South Asian faith groups. These were: limitations posed by written English; limitations posed by any written language; reliance on younger family members; low awareness of colorectal cancer and screening; and difficulties associated with faeces. Non-written information delivered verbally and interactively within faith or community settings was preferred across faith communities. Efforts to increase accessibility to colorectal cancer screening in South Asian communities should use local language broadcasts on ethnic media and face-to-face approaches within community and faith settings to increase awareness of colorectal cancer and screening, and address challenges posed by written materials.

  7. Immunologic studies in two patients with persistent lymphocytic thyroiditis, thyrotoxicosis, and low radioactive iodine uptake

    Energy Technology Data Exchange (ETDEWEB)

    Elliot, I.; Gupta, M.; Hostetter, A.; Sheeler, L.; Skillern, P.; Tubbs, R.

    1984-08-01

    Two patients with persistent lymphocytic thyroiditis and thyrotoxicosis were studied. Both patients presented with severe hyperthyroidism of nine months' duration and had nontender, small thyroid glands. Uptake of radioactive iodine (131I) was consistently low. Serum thyroxine and triiodothyronine levels remained elevated without remission until thyroidectomy. The serum thyroglobulin level was normal, but testing for microsomal antibody gave weakly positive results in one case. Thyroglobulin and thyroid stimulatory antibodies were not found. The ratio of helper to suppressor T cells was elevated in one case. Neither patient showed response to propranolol, prednisone, or iodine. Light microscopic and immunohistologic studies showed severe lymphocytic thyroiditis with formation of secondary lymphoid follicles. Lymphocytes were predominately T cells (OKT11-positive), primarily helper/inducer T cells (OKT4-positive). Hyperplastic nodules contained high immunoreactive thyroglobulin and thyroxine levels. Aberrant thymus was seen within the thyroid. These studies suggest the possibility of intrathyroidal stimulation and hydrolysis of thyroglobulin within thyroid cells and also support the hypothesis that T and B cell immunoregulatory defects are important in the pathogenesis of this disease.

  8. Radiotracer studies on the uptake of strontium by poly(styrene-DVB) resins containing iminodiacetic acid groups

    Energy Technology Data Exchange (ETDEWEB)

    Samanta, S.K. [Process Development Div., Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    1999-07-01

    The uptake of strontium has been studied using two commercially available chelating resins containing iminodiacetic acid functional groups. The resins have been characterized with respect to moisture content, swelling behaviour, ion exchange and chelating capacities. The effect of pH, sodium and strontium concentrations on the uptake of strontium has been determined by carrying out batch equilibration tests. The suitability of using such a resin for removal of radiostrontium from radioactive waste solutions has also been tested in laboratory-scale column experiments. (orig.)

  9. Sorptive Uptake Studies of an Aryl-Arsenical with Iron Oxide Composites on an Activated Carbon Support

    OpenAIRE

    2014-01-01

    Sorption uptake kinetics and equilibrium studies for 4-hydroxy-3-nitrobenzene arsonic acid (roxarsone) was evaluated with synthetic magnetite (Mag-P), commercial magnetite (Mag-C), magnetite 10%, 19%, and 32% composite material (CM-10, -19, -32) that contains granular activated carbon (GAC), and synthetic goethite at pH 7.00 in water at 21 °C for 24 h. GAC showed the highest sorptive removal of roxarsone and the relative uptake for each sorbent material with roxarsone are listed in descending...

  10. Uptake of permanganate from aqueous environment by surfactant modified montmorillonite batch and fixed bed studies

    Indian Academy of Sciences (India)

    N Mahadevaiah; B Vijayakumar; K Hemalatha; B S Jai Prakash

    2011-12-01

    Organo-clay was prepared by incorporating different amounts (in terms of CEC, ranging from 134–840 mg of quaternary ammonium cation (QACs) such as hexadecytrimethylammonium bromide ([C19H42N]Br) into the montmorillonite clay. Prepared organo-clays are characterized by CHN analyser and XRD to measure the amount of elemental content and interlayer spacing of surfactant modified clay. The batch experiments of sorption of permanganate from aqueous media by organo-clays was studied at different acidic strengths (pH 1–7). The experimental results show that the rate and amount of adsorption of permanganate was higher at lower pH compared to raw montmorillonite. Laboratory fixed bed experiments were conducted to evaluate the breakthrough time and nature of breakthrough curves. The shape of the breakthrough curves shows that the initial cationic surfactant loadings at 1.0 CEC of the clay is enough to enter the permanganate ions in to the interlamellar region of the surfactant modified smectile clays. These fixed bed studies were also applied to quantify the effect of bed-depth and breakthrough time during the uptake of permanganate. Calculation of thermodynamic parameters shows that the sorption of permanganate is spontaneous and follows the first order kinetics.

  11. 10 CFR 35.100 - Use of unsealed byproduct material for uptake, dilution, and excretion studies for which a...

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Use of unsealed byproduct material for uptake, dilution, and excretion studies for which a written directive is not required. 35.100 Section 35.100 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Unsealed Byproduct Material-Written...

  12. The Role of Learning Disability Nurses in Promoting Cervical Screening Uptake in Women with Intellectual Disabilities: A Qualitative Study

    Science.gov (United States)

    Lloyd, Jennifer L.; Coulson, Neil S.

    2014-01-01

    Research suggests that the uptake of cervical screening by women with intellectual disabilities (commonly known as learning disabilities within UK policy frameworks, practice areas and health services) is poor compared to women without intellectual disabilities. The present study explored learning disability nurses' experiences of supporting women…

  13. Evaluation of different normalization procedures for the calculation of the standardized uptake value in therapy response monitoring studies

    NARCIS (Netherlands)

    Vriens, Dennis; de Geus-Oei, Lioe-Fee; van Laarhoven, Hanneke W; Timmer-Bonte, Johanna N H; Krabbe, Paul F M; Visser, Eric P; Oyen, Wim J G

    2009-01-01

    OBJECTIVES: The aim of this prospective study was to assess the influence of different normalization procedures on relative changes in standardized uptake values (SUV) of F-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) for the assessment of chemotherapy response in patients with

  14. Incidental pituitary uptake on whole-body {sup 18}F-FDG PET/CT: a multicentre study

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Shin Young; Lee, Sang-Woo; Kang, Sungmin; Seo, Ji-Hyoung; Ahn, Byeong-Cheol; Lee, Jaetae [Kyungpook National University Hospital, Department of Nuclear Medicine, Daegu (Korea, Republic of); Lee, Hui Joong [Kyungpook National University Hospital, Radiology, Daegu (Korea, Republic of); Chun, Kyung Ah; Cho, Ihn Ho [Yeungnam University Medical Center, Department of Nuclear Medicine, Daegu (Korea, Republic of); Won, Kyung Sook; Zeon, Seok Kil [Keimyung University Dongsan Medical Center, Department of Nuclear Medicine, Daegu (Korea, Republic of)

    2010-12-15

    The purpose of this study was to determine the incidence of incidental pituitary uptake on whole-body {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and to investigate its clinical significance. The files of 40,967 patients who underwent whole-body FDG PET/CT were retrospectively reviewed. Quantification of pituitary metabolic activity was obtained by using the maximum standardized uptake value (SUV{sub max}). Hormone assays and pituitary MRIs were performed to assess pituitary lesions. Focally increased pituitary FDG uptake on PET/CT was found in 30 of 40,967 patients, accounting for an incidence of 0.073%. The mean SUV{sub max} of 30 patients was 8.9 {+-} 6.6 (range: 3.2-32.6). Histological diagnosis was obtained in three patients and included two growth hormone-secreting adenomas and one non-functioning adenoma. Hormone assays were performed on serum samples from 11 patients, 2 of whom were shown to have hypersecretion of pituitary hormone. MRI was performed on 19 patients. Abnormal MRI findings suggesting a pituitary mass were found in 18 of 19 cases (94.7%). The mean SUV{sub max} calculated without correction for partial volume effect for macroadenomas was significantly higher than the SUV{sub max} for microadenomas (11.5 {+-} 8.4 vs 4.8 {+-} 1.3; p < 0.05). There were no cases diagnosed with metastasis to the pituitary gland during clinical follow-up. Incidental pituitary FDG uptake was a very rare finding. Cases with incidental pituitary FDG uptake were diagnosed primarily with clinically non-functioning adenomas, and there were also a few functioning adenomas. Further evaluations, including hormone assays and pituitary MRI, are warranted when pituitary uptake is found on FDG PET/CT. (orig.)

  15. Macro- and microspectroscopic study of Nd (III) uptake mechanisms in hardened cement paste.

    Science.gov (United States)

    Mandaliev, Peter; Dähn, Rainer; Wehrli, Bernhard; Wieland, Erich

    2009-11-01

    Cement is an important component in repositories for low-level and intermediate-level radioactive waste. Nd uptake by hardened cement paste (HCP) has been investigated with the aim of developing a mechanistic understanding of the immobilization processes of trivalent lanthanides and actinides in HCP on the molecular level. Information on the microstructure of HCP, the Nd distribution in the cement matrix, and the coordination environment of Nd in these matrices was gained from the combined use of scanning electron microscopy (SEM), synchrotron-based micro-X-ray fluorescence (micro-XRF), micro-X-ray (micro-XAS), and bulk-X-ray absorption spectroscopy (bulk-XAS) on Nd doped cement samples. The samples were reacted over periods of time between 15 min and 200 days. SEM and micro-XRF investigations suggest preferential Nd accumulation in rims around "inner"-calcium silicate hydrates (C-S-H). The EXAFS data indicate that the coordination environment of Nd taken up by HCP was dependent on reaction time. Changes in the structural parameters derived from EXAFS support the idea of Nd incorporation into the structure of C-S-H phases. The Nd binding mechanisms proposed in this study have implication for an overall assessment of the safe disposal of trivalent actinides in cement-based repositories for radioactive waste.

  16. Adapting Yeast as Model to Study Ricin Toxin A Uptake and Trafficking

    Directory of Open Access Journals (Sweden)

    Björn Becker

    2011-07-01

    Full Text Available The plant A/B toxin ricin represents a heterodimeric glycoprotein belonging to the family of ribosome inactivating proteins, RIPs. Its toxicity towards eukaryotic cells results from the depurination of 28S rRNA due to the N-glycosidic activity of ricin toxin A chain, RTA. Since the extention of RTA by a mammalian-specific endoplasmic reticulum (ER retention signal (KDEL significantly increases RTA in vivo toxicity against mammalian cells, we here analyzed the phenotypic effect of RTA carrying the yeast-specific ER retention motif HDEL. Interestingly, such a toxin (RTAHDEL showed a similar cytotoxic effect on yeast as a corresponding RTAKDEL variant on HeLa cells. Furthermore, we established a powerful yeast bioassay for RTA in vivo uptake and trafficking which is based on the measurement of dissolved oxygen in toxin-treated spheroplast cultures of S. cerevisiae. We show that yeast spheroplasts are highly sensitive against external applied RTA and further demonstrate that its toxicity is greatly enhanced by replacing the C-terminal KDEL motif by HDEL. Based on the RTA resistant phenotype seen in yeast knock-out mutants defective in early steps of endocytosis (∆end3 and/or in RTA depurination activity on 28S rRNA (∆rpl12B we feel that the yeast-based bioassay described in this study is a powerful tool to dissect intracellular A/B toxin transport from the plasma membrane through the endosomal compartment to the ER.

  17. Study of element uptake in plants from the soil to assess environmental contamination by toxic elements

    CERN Document Server

    En, Z; Tsipin, V V; Tillaev, T; Jumaniyazova, G I

    2003-01-01

    Uptake of various elements by plants through the root system from the soil was studied. Vegetation experiments with cotton and white beet were carried out in the control and test fields. The test fields were enriched with phyto-bacterial strains capable of dissolving insoluble phosphate compounds. Analytical work involved analysis of blank, control and test soil samples and analysis of plants sampled in different growing periods: periods of first sprouts, florescence and ripening of the plants. Multielement analyses of soil and plant samples were carried out by instrumental neutron activation techniques using our WWR-SM research reactor. Results of the measurements have shown that macro- and microelement composition of the analyzed soil samples were consistent to clark contents except for copper. Our experiments have resulted that the concentration levels of copper in the soils were within 300-450 mg/kg, and its average concentration in cotton leaves was about similar to 35 mg/kg while in beet leaves it reach...

  18. Adapting yeast as model to study ricin toxin a uptake and trafficking.

    Science.gov (United States)

    Becker, Björn; Schmitt, Manfred J

    2011-07-01

    The plant A/B toxin ricin represents a heterodimeric glycoprotein belonging to the family of ribosome inactivating proteins, RIPs. Its toxicity towards eukaryotic cells results from the depurination of 28S rRNA due to the N-glycosidic activity of ricin toxin A chain, RTA. Since the extention of RTA by a mammalian-specific endoplasmic reticulum (ER) retention signal (KDEL) significantly increases RTA in vivo toxicity against mammalian cells, we here analyzed the phenotypic effect of RTA carrying the yeast-specific ER retention motif HDEL. Interestingly, such a toxin (RTA(HDEL)) showed a similar cytotoxic effect on yeast as a corresponding RTA(KDEL) variant on HeLa cells. Furthermore, we established a powerful yeast bioassay for RTA in vivo uptake and trafficking which is based on the measurement of dissolved oxygen in toxin-treated spheroplast cultures of S. cerevisiae. We show that yeast spheroplasts are highly sensitive against external applied RTA and further demonstrate that its toxicity is greatly enhanced by replacing the C-terminal KDEL motif by HDEL. Based on the RTA resistant phenotype seen in yeast knock-out mutants defective in early steps of endocytosis (∆end3) and/or in RTA depurination activity on 28S rRNA (∆rpl12B) we feel that the yeast-based bioassay described in this study is a powerful tool to dissect intracellular A/B toxin transport from the plasma membrane through the endosomal compartment to the ER.

  19. Nonrecirculating Hydroponic System Suitable for Uptake Studies at Very Low Nutrient Concentrations 1

    Science.gov (United States)

    Gutschick, Vincent P.; Kay, Lou Ellen

    1991-01-01

    We describe the mechanical, electronic, hydraulic, and structural design of a nonrecirculating hydroponic system. The system is particularly suited to studies at very low nutrient concentrations, for which on-line concentration monitoring methods either do not exist or are costly and limited to monitoring relatively few individual plants. Solutions are mixed automatically to chosen concentrations, which can be set differently for every pump fed from a master supply of deionized water and nutrient concentrates. Pumping rates can be varied over a 50-fold range, up to 400 liters per day, which suffices to maintain a number of large, post-seedling plants in rapid growth at (sub)micromolar levels of N and P. The outflow of each pump is divided among as many as 12 separate root chambers. In each chamber one may monitor uptake by individual plant roots or segments thereof, by measuring nutrient depletion in batch samples of solution. The system is constructed from nontoxic materials that do not adsorb nutrient ions; no transient shifts of nitrate and phosphate concentrations are observable at the submicromolar level. Nonrecirculation of solutions limits problems of pH shifts, microbial contamination, and cumulative imbalances in unmonitored nutrients. We note several disadvantages, principally related to high consumption of deionized water and solutes. The reciprocating pumps can be constructed inexpensively, particularly by the researcher. We also report previously unattainable control of passive temperature rise of chambers exposed to full sunlight, by use of white epoxy paint. PMID:16668100

  20. Sustainability Study on Heavy Metal Uptake in Neem Biodiesel Using Selective Catalytic Preparation and Hyphenated Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Mirella Elkadi

    2014-04-01

    Full Text Available It is common knowledge that the presence of trace metals in biofuels can be detrimental to the environment and long-term sustainable development. This study provides an insight into selective catalytic preparation of biofuel to compare uptake of trace metals in the biodiesel fraction with preferential base catalysts. The role of specific metal hydroxides in controlling trace metal content in biofuel production is relatively unexplored, and the effect of different homogeneous catalysts (NaOH, KOH on metal retention in biodiesel from commercial neem oil was examined. A detailed study of this nature of catalyst vs. metal uptake is in the interest of sustainable living and could make a significant contribution to biofuels research. Both catalysts displayed variable uptake for certain toxic elements, which was attributed to the behavior of the catalyst in the reaction mixture. A general comparison reflected specific trends in metal retention (ICP-MS with the use of different base catalysts. Challenges encountered by extending the study and using a heterogeneous catalyst (CaO are presented. Our work could play a significant role in influencing catalyzed transesterfication processes to control elemental and toxic metal uptake in biofuels. The impact of our work on sustainable living is presented.

  1. Incorporation study of {sup 18}FDG through its uptake into tumour-derived cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Flavia M.; Nascimento, Leonardo T.C.; Santos, Raquel G., E-mail: fnc@cdtn.br, E-mail: raqueou@uol.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN/MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    In vitro tests of radiopharmaceuticals are an important instrument to study their mechanisms of action, binding and incorporation. {sup 18}FDG is the most used radiopharmaceutical for diagnostics positron emission tomography (PET) on oncology, on the basis of accelerated rates of absorption of glucose in cell malignancies. This radiotracer has been routinely produced at CDTN; and therefore, it was selected for preliminary assays due to its availability. Nowadays, UPPR at CDTN produces routinely {sup 18}FDG for the local PET Centers but others PET radiopharmaceuticals are in development such as {sup 18}F-Fluorocholine and {sup 18}F-Fluorothymidine. According to the Brazilian Health Regulatory Agency (ANVISA) it is necessary to validate and register these new radiopharmaceuticals in order to get the approval for their commercialization. Targeting efficacy is one of the important issues to be evaluated during radiopharmaceutical validation. The aim of this study was to develop a standard protocol to determine tumor targeting efficacy of PET radiopharmaceuticals in vitro. Therefore it was developed a protocol based on the incorporation og {sup 18} FDG through the uptake in different tumor-derived cell lines. Three variables were investigated for the standardization of the test: the number of cells to be seeded in 96-well plates, the time of incubation with the radiopharmaceutical and the radiotracer concentration. The standardized protocol was considered suitable for {sup 18}FDG incorporation assay and showed reproductive results. The protocol developed in this work will pave the way for the in vitro studies of incorporation of the new PET radiopharmaceuticals to be produced at UPPR-CDTN, such as: {sup 18}F-Fluorocholine and {sup 18}F-Fluorothymidine. (author)

  2. Modified conceptual model for compensated root water uptake - A simulation study

    Science.gov (United States)

    Peters, Andre

    2016-03-01

    Modeling root water uptake within the macroscopic approach is usually done by introducing a sink term in the Richards equation. This sink term represents potential water uptake reduced by a so-called stress reduction factor accounting for stress due to high suctions, oxygen deficit or salinity. Since stress in some parts of the soil can be compensated by enhanced water uptake in less stressed parts, several compensation models have been suggested. One of them is the empirical model of Jarvis, which is often applied due to its mathematical elegance and simplicity. However, it has been discussed that under certain conditions and assumptions this model might predict too high transpiration rates, which are not in agreement with the assumed stress reduction function. The aim of this paper is (i) to analyze these inconsistencies and (ii) to introduce a simple constraint for transpiration in a way as if the complete water would be taken form the location with highest uptake rate in the uncompensated case. Transpiration from 50 cm deep soils with hydraulic functions representing different textures, ranging from a clay loam to a coarse sand, was simulated with the original and the modified model using HYDRUS-1D. Root distribution was assumed to be uniform or linearly decreasing with depth. In case of the fine textured soils and uniform root density, the original model predicted transpiration equal to potential transpiration even when the complete root domain was already heavily stressed if the maximum enhancement factor for uptake was 2. These results are not in agreement with the original meaning of the stress reduction function. The modification eliminates the inconsistencies by limiting transpiration to a maximum value based on the highest uncompensated uptake rate in the root zone. It does neither increase the mathematical complexity nor require any additional parameters.

  3. Surface Spectroscopy Studies of the Reactive Uptake of Ozone on Alkali Halides

    Science.gov (United States)

    Newberg, J. T.; Hemminger, J. C.

    2003-12-01

    the O(1s) photoelectron peak. Initial XPS spectra of salts in the vacuum chamber prior to ozone exposure indicated that the salts were either devoid of oxygen, or contained a small amount of oxygen from strongly adsorbed water under ultra-high vacuum. In all cases, in-vacuo exposure of the salts to ozone lead to an increase in O(1s) photoelectron signal. For NaCl this was surprising since previous studies have been interpreted to indicate that ozone is essentially unreactive towards solid NaCl. The initial uptake of oxygen on the surface gave a broad O(1s) peak, indicating that there are several types of oxygen species on the surface. Reference spectra were obtained for NaClO2, NaClO3, and NaClO4 salts. The O(1s) binding energies in these reference spectra increased in series with NaClO2 doses. The oxygen uptake upon ozone exposure to alkali bromide and iodide salts were also investigated and compared to reference salts. Future work will incorporate the influence of adsorbed water and subsequent ozone exposures on the surface chemistry of salts.

  4. A Novel Biosorbent, Water-Hyacinth, Uptaking Methylene Blue from Aqueous Solution: Kinetics and Equilibrium Studies

    Directory of Open Access Journals (Sweden)

    Md. Nasir Uddin

    2014-01-01

    Full Text Available The adsorption of MB dye from aqueous solution onto HCl acid treated water-hyacinth (H-WH was investigated by carried out batch sorption experiments. The effect of process parameters such as pH, adsorbent dosage, concentrations and contact time, and ionic strength were studied. Adsorption of MB onto H-WH was found highly pH dependent and ionic strength shows negative impact on MB removal. To predict the biosorption isotherms and to determine the characteristic parameters for process design, Langmuir, Freundlich, Temkin, and Halsey isotherms models were utilized to equilibrium data. The adsorption kinetics was tested for pseudo-first-order (PFO, pseudo-second-order (PSO, intraparticle diffusion (IPD, and Bangham’s kinetic models. The Langmuir isotherm model showed the goodness-of-fit among the tested models for equilibrium adsorption of MB over H-WH and indicated the maximum adsorption capacity as 63.30 mg/g. Higher coefficient of determination (R2>0.99 and better agreement between the qe (experimental and qe (calculated values predicted that PSO kinetic model showed the goodness-of-fit for kinetic data along with rate constant 1.66×10-3, 4.42×10-3, and 3.57×10-3 mg·g-1min⁡-1/2⁡, respectively, for the studied concentration range. At the initial stage of adsorption, the overall rate of dye uptake was found to be dominated by external mass transfer, and afterwards, it is controlled by IPD mechanism.

  5. Experimental and modelling study on the uptake and desorption kinetics of 133Ba by suspended estuarine sediments from southern Spain.

    Science.gov (United States)

    Barros, H; Abril, J M

    2004-02-01

    Dispersion of pollutants in aquatic environments depends on their uptake by suspended solids. This work deals with the uptake kinetics of 133Ba (gamma-emitter and a good analogue of 226Ra) by suspended estuarine sediments (which can be resuspended into the water column under certain conditions). This study presents a wide set of tracing experiments, including second tracing, decantation and desorption processes. The purpose is to characterize 133Ba uptake by sediments and to investigate the use and limitations of box models in order to describe the uptake kinetics. Water and sediment samples were collected in the Huelva estuary (Spain), where environmental 226Ra concentrations have been increased by two phosphate fertilizer industries. Samples were characterized by granulometric, organic carbon content, cation exchange capacity and XRF-EP analyses. Results revealed three-step kinetics, with characteristic times of minutes, hours and days. These results enabled the selection and calibration of a suitable box model and facilitated the testing of its use as a fully predictive tool.

  6. Comparative bone uptake study of alendronate sodium from vaginal suppositories prepared with polyethylene glycol and massa estarinum bases

    Directory of Open Access Journals (Sweden)

    Derya İlem-Özdemir

    2013-09-01

    Full Text Available The aim of this study was to compare the bone uptake of alendronate sodium (ALD from vaginal suppositories prepared with massa estarinum AB (ME and polyethylene glycol 1500 (PEG bases. For this purpose, ALD was radiolabeled with 99mTecnetium Pertechnetate (99mTc by direct method. Radiochemical purity and stability of 99mTc-ALD was performed with chromatographic studies. 99mTc-ALD containing suppositories were prepared with ME and PEG bases. Physical properties of suppositories were evaluated. The physicochemical diffusion study was carried out to compare the release of ALD from different suppository bases. The bone uptake of 99mTc-ALD was observed by gamma scintigraphy studies. 99mTc-ALD containing suppositories were administrated to rabbits via vaginal route. The scintigraphic images were obtained with a gamma camera at different time intervals up to 240 minutes. According to our studies, radiochemical purity of 99mTc-ALD was observed more than 95% up to 6 hours. At 240 minutes of physicochemical diffusion studies, released ALD has 0.620 ± 0.091 mm and 10.465 ± 0.651 mm diameter zone from ME and PEG base suppositories respectively. According to the gamma scintigraphy studies, although no bone uptake observed after ME suppositories application, rabbit’s bones were clearly visible after PEG suppositories applied. The results of physicochemical diffusion and gamma scintigraphy studies were found compatible in each other

  7. Uptake of perfluoroalkyl acids into edible crops via land applied biosolids: Field and greenhouse studies

    Science.gov (United States)

    The presence of perfluoroalkyl acids (PFAAs) in biosolids destined for use in agriculture has raised concerns about their potential to enter the terrestrial food chain via bioaccumulation in edible plants. Uptake of PFAAs by greenhouse lettuce ( Lactuca sativa) and tomato (Lycope...

  8. First example of diglycolamide-grafted resins: synthesis, characterization, and actinide uptake studies

    NARCIS (Netherlands)

    Mohapatra, Prasanta; Ansari, Seraj A.; Iqbal, M.; Huskens, Jurriaan; Verboom, Willem

    2014-01-01

    Two diglycolamide (DGA)-functionalized chelating extraction resins were prepared for the first time by grafting onto a silica matrix and were evaluated for their actinide ion uptake behavior. The resins with one and two DGA moieties, termed as resin-I and resin-II, were quite efficient for the

  9. First example of diglycolamide-grafted resins: synthesis, characterization, and actinide uptake studies

    NARCIS (Netherlands)

    Mohapatra, Prasanta; Ansari, Seraj A.; Iqbal, M.; Huskens, Jurriaan; Verboom, Willem

    2014-01-01

    Two diglycolamide (DGA)-functionalized chelating extraction resins were prepared for the first time by grafting onto a silica matrix and were evaluated for their actinide ion uptake behavior. The resins with one and two DGA moieties, termed as resin-I and resin-II, were quite efficient for the actin

  10. An experimental study of the influence of the microelements on the uptake of macroelements by plants

    NARCIS (Netherlands)

    el- Kholi, A.F.

    1961-01-01

    Since trace elements are generally involved in enzymic reactions taking place within the plant an imbalance in the trace nutrient supply could be expected also to affect the uptake of major elements by roots and their translocation through the plant.

    Pot experiments with ascending doses of trace

  11. A study of the changes of breast uptake in menstrual cycle on {sup 18}F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hoon Hee; Tak, Yeo Jin [Dept. of Radiological Technology, Shingu College, Sungnam (Korea, Republic of); Park, Min Soo [Dept. of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul (Korea, Republic of); Lee, Ju Young [Graduate School of Public Health, Yonsei University, Seoul (Korea, Republic of)

    2015-04-15

    {sup 18}F-FDG PET/CT has been known a useful modality to diagnose high-glucose-using cells such as cancer cells by glucose metabolism of FDG. Mainly, FDG takes on cancer and inflammatory cells; however, there have been FDG uptakes on normal tissues by individual physiological characteristics, occasionally. Especially, in fertile females, unusual FDG uptake of breast changes as the menstrual cycle, and disturb diagnosis. Therefore, the study aimed to evaluate the change of breast FDG uptake in menstrual cycle on {sup 18}F-FDG PET/CT. 160 females (34±3.5 years old) who do not undergo a gynecologic anamnesis and have regular menstrual cycle over the previous 6 months were examined. They were divided 4 groups (each 40 patients) as flow phase, proliferative phase, ovulatory phase and secretory phase using Pregnancy Calculator 0.14. and history taking. Discovery Ste (GE Healthcare, Milwaukee, Mi, USA) was used a s PET/CT. We analyzed SUVs on a ccumulated r egion on b reast, and 3 nuclear medicine specialists did the Blind test. SUVs on the Breast were flow phase (1.64±0.25), proliferative phase (0.93±0.28), ovulatory phase (1.66±0.26) and secretory phase (1.77±0.28). It showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). In gross analysis, the accumulation of breast was divided into 3 grades as comparing with lung and liver. The breast’s uptake was equal to lung (Grade Ⅰ); between lung and liver (Grade II); equal to or greater than liver (Grade III). The results showed high uptake value in secretory, flow phase and ovulatory phase (p<0.05). In fertile females, FDG uptake of breast changed as menstrual cycle, and it available to diagnose breast disease. Therefore, we consider reducing false-negative finding of breast disease, by doing examination on appropriate period through history taking about individual menstrual cycle.

  12. Contributing factors to influenza vaccine uptake in general hospitals: an explorative management questionnaire study from the Netherlands

    Directory of Open Access Journals (Sweden)

    Riphagen-Dalhuisen Josien

    2012-12-01

    Full Text Available Abstract Background The influenza vaccination rate in hospitals among health care workers in Europe remains low. As there is a lack of research about management factors we assessed factors reported by administrators of general hospitals that are associated with the influenza vaccine uptake among health care workers. Methods All 81 general hospitals in the Netherlands were approached to participate in a self-administered questionnaire study. The questionnaire was directed at the hospital administrators. The following factors were addressed: beliefs about the effectiveness of the influenza vaccine, whether the hospital had a written policy on influenza vaccination and how the hospital informed their staff about influenza vaccination. The questionnaire also included questions about mandatory vaccination, whether it was free of charge and how delivered as well as the vaccination campaign costs. The outcome of this one-season survey is the self-reported overall influenza vaccination rate of health care workers. Results In all, 79 of 81 hospitals that were approached were willing to participate and therefore received a questionnaire. Of these, 42 were returned (response rate 52%. Overall influenza vaccination rate among health care workers in our sample was 17.7% (95% confidence interval: 14.6% to 20.8%. Hospitals in which the administrators agreed with positive statements concerning the influenza vaccination had a slightly higher, but non-significant, vaccine uptake. There was a 9% higher vaccine uptake in hospitals that spent more than €1250,- on the vaccination campaign (24.0% versus 15.0%; 95% confidence interval from 0.7% to 17.3%. Conclusions Agreement with positive statements about management factors with regard to influenza vaccination were not associated with the uptake. More economic investments were related with a higher vaccine uptake; the reasons for this should be explored further.

  13. Batch sorption and spectroscopic speciation studies of neptunium uptake by montmorillonite and corundum

    Science.gov (United States)

    Elo, O.; Müller, K.; Ikeda-Ohno, A.; Bok, F.; Scheinost, A. C.; Hölttä, P.; Huittinen, N.

    2017-02-01

    Detailed information on neptunium(V) speciation on montmorillonite and corundum surfaces was obtained by batch sorption and desorption studies combined with surface complexation modelling using the Diffuse Double-Layer (DDL) model, in situ time-resolved Attenuated Total Reflection Fourier-Transform Infrared (ATR FT-IR) and X-ray absorption (XAS) spectroscopies. The pH-dependent batch sorption studies and the spectroscopic investigations were conducted under carbonate-free conditions in 10 mM NaClO4 or 10 mM NaCl. Solid concentrations of 0.5 g/l and 5 g/l were used depending on the experiment. The neptunium(V) desorption from the two mineral surfaces was investigated at pH values ranging from 8 to 10, using the replenishment technique. Neptunium(V) was found to desorb from the mineral surface, however, the extent of desorption was dependent on the solution pH. The desorption of neptunium(V) was confirmed in the ATR FT-IR spectroscopic studies at pH 10, where all of the identified inner-sphere complexed neptunium(V), characterized by a vibrational band at 790 cm-1, was desorbed from both mineral surfaces upon flushing the mineral films with a blank electrolyte solution. In XAS investigations of neptunium(V) uptake by corundum, the obtained structural parameters confirm the formation of an inner-sphere complex adsorbed on the surface in a bidentate fashion. As the inner-sphere complexes found in the IR-studies are characterized by identical sorption bands on both corundum and montmorillonite, we tentatively assigned the neptunium(V) inner-sphere complex on montmorillonite to the same bidentate complex found on corundum in the XAS investigations. Finally, the obtained batch sorption and spectroscopic results were modelled with surface complexation modelling to explain the neptunium(V) speciation on montmorillonite over the entire investigated pH range. The modelling results show that cation exchange in the interlayer space as well as two pH-dependent surface complexes

  14. Reproductive Toxicity and Life History Study of Silver Nanoparticle Effect, Uptake and Transport in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Jane Geisler-Lee

    2014-04-01

    Full Text Available Concerns about nanotechnology have prompted studies on how the release of these engineered nanoparticles impact our environment. Herein, the impact of 20 nm silver nanoparticles (AgNPs on the life history traits of Arabidopsis thaliana was studied in both above- and below-ground parts, at macroscopic and microscopic scales. Both gross phenotypes (in contrast to microscopic phenotypes and routes of transport and accumulation were investigated from roots to shoots. Wild type Arabidopsis growing in soil, regularly irrigated with 75 μg/L of AgNPs, did not show any obvious morphological change. However, their vegetative development was prolonged by two to three days and their reproductive growth shortened by three to four days. In addition, the germination rates of offspring decreased drastically over three generations. These findings confirmed that AgNPs induce abiotic stress and cause reproductive toxicity in Arabidopsis. To trace transport of AgNPs, this study also included an Arabidopsis reporter line genetically transformed with a green fluorescent protein and grown in an optical transparent medium with 75 μg/L AgNPs. AgNPs followed three routes: (1 At seven days after planting (DAP at S1.0 (stages defined by Boyes et al. 2001 [41], AgNPs attached to the surface of primary roots and then entered their root tips; (2 At 14 DAP at S1.04, as primary roots grew longer, AgNPs gradually moved into roots and entered new lateral root primordia and root hairs; (3 At 17 DAP at S1.06 when the Arabidopsis root system had developed multiple lateral roots, AgNPs were present in vascular tissue and throughout the whole plant from root to shoot. In some cases, if cotyledons of the Arabidopsis seedlings were immersed in melted transparent medium, then AgNPs were taken up by and accumulated in stomatal guard cells. These findings in Arabidopsis are the first to document specific routes and rates of AgNP uptake in vivo and in situ.

  15. Multi-Elemental Profiling of Tibial and Maxillary Trabecular Bone in Ovariectomised Rats.

    Science.gov (United States)

    Han, Pingping; Lu, Shifeier; Zhou, Yinghong; Moromizato, Karine; Du, Zhibin; Friis, Thor; Xiao, Yin

    2016-01-01

    Atomic minerals are the smallest components of bone and the content of Ca, being the most abundant mineral in bone, correlates strongly with the risk of osteoporosis. Postmenopausal women have a far greater risk of suffering from OP due to low Ca concentrations in their bones and this is associated with low bone mass and higher bone fracture rates. However, bone strength is determined not only by Ca level, but also a number of metallic and non-metallic elements in bone. Thus, in this study, the difference of metallic and non-metallic elements in ovariectomy-induced osteoporosis tibial and maxillary trabecular bone was investigated in comparison with sham operated normal bone by laser ablation inductively-coupled plasma mass spectrometry using a rat model. The results demonstrated that the average concentrations of (25)Mg, (28)Si, (39)K, (47)Ti, (56)Fe, (59)Co, (77)Se, (88)Sr, (137)Ba, and (208)Pb were generally higher in tibia than those in maxilla. Compared with the sham group, Ovariectomy induced more significant changes of these elements in tibia than maxilla, indicating tibial trabecular bones are more sensitive to changes of circulating estrogen. In addition, the concentrations of (28)Si, (77)Se, (208)Pb, and Ca/P ratios were higher in tibia and maxilla in ovariectomised rats than those in normal bone at all time-points. The present study indicates that ovariectomy could significantly impact the element distribution and concentrations between tibia and maxilla.

  16. Multi-Elemental Profiling of Tibial and Maxillary Trabecular Bone in Ovariectomised Rats

    Directory of Open Access Journals (Sweden)

    Pingping Han

    2016-06-01

    Full Text Available Atomic minerals are the smallest components of bone and the content of Ca, being the most abundant mineral in bone, correlates strongly with the risk of osteoporosis. Postmenopausal women have a far greater risk of suffering from OP due to low Ca concentrations in their bones and this is associated with low bone mass and higher bone fracture rates. However, bone strength is determined not only by Ca level, but also a number of metallic and non-metallic elements in bone. Thus, in this study, the difference of metallic and non-metallic elements in ovariectomy-induced osteoporosis tibial and maxillary trabecular bone was investigated in comparison with sham operated normal bone by laser ablation inductively-coupled plasma mass spectrometry using a rat model. The results demonstrated that the average concentrations of 25Mg, 28Si, 39K, 47Ti, 56Fe, 59Co, 77Se, 88Sr, 137Ba, and 208Pb were generally higher in tibia than those in maxilla. Compared with the sham group, Ovariectomy induced more significant changes of these elements in tibia than maxilla, indicating tibial trabecular bones are more sensitive to changes of circulating estrogen. In addition, the concentrations of 28Si, 77Se, 208Pb, and Ca/P ratios were higher in tibia and maxilla in ovariectomised rats than those in normal bone at all time-points. The present study indicates that ovariectomy could significantly impact the element distribution and concentrations between tibia and maxilla.

  17. Multi-elemental mapping of a speleothem using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Q.L.; Motto-Ros, V. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); Lei, W.Q. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai (China); Boueri, M. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); Zheng, L.J.; Zeng, H.P. [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai (China); Bar-Matthews, M.; Ayalon, A. [Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem (Israel); Panczer, G. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS UMR 5620, LPCML F-69622, Lyon (France); Yu, J., E-mail: jin.yu@lasim.univ-lyon1.f [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France)

    2010-08-15

    Speleothems represent an important record of the paleoclimate, and more generally past environmental changes thanks to their laminar structure which is related to variations in rainfall and vegetation throughout the seasons and to their elemental as well as structural compositions which are sensitive to climatic and environmental conditions during their growth. Studies of their composition, especially those with spatial resolution, reveal rich information for paleoclimatology. In this paper, we demonstrate that laser-induced breakdown spectroscopy (LIBS) provides a suitable tool for elemental analysis and especially for 2-dimensional elemental mapping of speleothems. Main, minor, as well as trace elements can be analyzed with this technique. The temporal evolution of the induced plasma is first studied in order to determine a suitable detection window for emission spectrum recording following the impact of the laser pulse on the sample. The matrix effect is then evaluated with a scan on the sample surface by measuring the electron density and the temperature of the plasmas at different positions of the analyzed surface. Concentration mapping is performed for minor and trace elements such as Na, Mg, Al, Si, K, Fe and Sr, by measuring relative variations of line emission intensities from these elements. Finally, correlations in concentration among detected elements are determined. Groups of correlated elements can be attributed to different mineralogical phases.

  18. Cellular uptake and imaging studies of glycosylated silica nanoprobe (GSN in human colon adenocarcinoma (HT 29 cell line

    Directory of Open Access Journals (Sweden)

    Mehravi B

    2013-08-01

    Full Text Available Bita Mehravi,1 Mohsen Ahmadi,1 Massoud Amanlou,2 Ahmad Mostaar,1 Mehdi Shafiee Ardestani,3 Negar Ghalandarlaki41Biomedical Engineering and Medical Physics Department, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 2Department of Medicinal Chemistry, Faculty of Pharmacy and Drug Design and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran; 3Department of Radiopharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Biological Science, School of Science, Science and Research branch, Islamic Azad University, Tehran, IranPurpose: In recent years, molecular imaging by magnetic resonance imaging (MRI has gained prominence in the detection of tumor cells. The scope of this study is on molecular imaging and on the cellular uptake study of a glycosylated silica nanoprobe (GSN.Methods: In this study, intracellular uptake (HT 29 cell line of GSN was analyzed quantitatively and qualitatively with inductively coupled plasma atomic emission spectroscopy, flow cytometry, and fluorescent microscopy. In vitro and in vivo relaxometry of this nanoparticle was determined using a 3 Tesla MRI; biodistribution of GSN and Magnevist® were measured in different tissues.Results: Results suggest that the cellular uptake of GSN was about 70%. The r1 relaxivity of this nanoparticle in the cells was measured to be 12.9 ± 1.6 mM-1 s-1 and on a per lanthanide gadolinium (Gd3+ basis. Results also indicate an average cellular uptake of 0.7 ± 0.009 pg Gd3+ per cell. It should be noted that 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay demonstrated that the cells were effectively labeled without cytotoxicity, and that using MRI for quantitative estimation of delivery and uptake of targeted contrast agents and early detection of human colon cancer cells using targeted contrast agents, is feasible.Conclusion: These results showed that GSN provided a

  19. An in vitro Study on the Adsorption, Absorption and Uptake Capacity of Zn by the Bioremediator Trichoderma atroviride

    Directory of Open Access Journals (Sweden)

    Mazyar Yazdani

    2010-01-01

    Full Text Available The concentrations of Zn in the sediment of a polluted river at the Serdang Industrial Area were determined. These polluted sediment samples revealed high level of Zn (219. 27 µg/g. Isolation of fungi from this polluted sediment was also carried out using Rose Bengal Agar (RBA. The isolated fungi were exposed to different concentrations of Zn (0-6000 mg/L on Potato Dextrose Agar (PDA to find the most tolerant isolate. Trichoderma atroviride was found to have the highest tolerance and it was studied for growth rate, Zn uptake capacity, its tolerance to Zn and also localization of Zn by using Potato Dextrose Broth (PDB as the liquid culture medium. In the present study the results found out that the uptake capacity of T. atroviride ranged from 18.1-26.7 mg/g in liquid media at Zn concentrations from 500 to 1000 mg/L. The isolate showed 47.6-64% adsorption and 30.4¬45.1% absorption for Zn. Based on the present study, 5.7-7.4% of Zn removal was observed due to biomass washing. The high adsorption, relatively low absorption and high uptake capacity of Zn suggest that T. atroviride is a potential bioremediator of Zn. However, further studies are needed to confirm its practical use as a bioremediating agent for Zn under field conditions.

  20. Feasibility Study of the Permeability and Uptake of Mesoporous Silica Nanoparticles across the Blood-Brain Barrier

    OpenAIRE

    Baghirov, Habib; Karaman, Didem; Viitala, Tapani; Duchanoy, Alain; Lou, Yan-Ru; Mamaeva, Veronika; Pryazhnikov, Evgeny; Khiroug, Leonard; Davies, Catharina de Lange; Sahlgren, Cecilia; Rosenholm, Jessica M

    2016-01-01

    Drug delivery into the brain is impeded by the blood-brain-barrier (BBB) that filters out the vast majority of drugs after systemic administration. In this work, we assessed the transport, uptake and cytotoxicity of promising drug nanocarriers, mesoporous silica nanoparticles (MSNs), in in vitro models of the BBB. RBE4 rat brain endothelial cells and Madin-Darby canine kidney epithelial cells, strain II, were used as BBB models. We studied spherical and rod-shaped MSNs with the following modi...

  1. {sup 99m}TcO(BAT-NI), a novel nitroimidazole tracer: in vivo uptake studies in ischaemic myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Hoffend, J.; Linke, G.; Mohammed, A.; Haberkorn, U. [Department of Radiology, Division of Nuclear Medicine, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg (Germany); Tiefenbacher, C.P. [Department of Internal Medicine, Division of Cardiology, University of Heidelberg, Heidelberg (Germany); Eisenhut, M. [German Cancer Research Centre, Heidelberg (Germany)

    2003-04-01

    Myocardial perfusion single-photon emission tomography (SPET) performed with cationic technetium-99m complexes indicates ischaemic areas as cold lesions. By contrast, nitroimidazole derivatives labelled with fluorine-18 or {sup 99m}Tc have recently shown promising results for hot spot imaging of ischaemic myocardium. This study evaluates {sup 99m}TcO(BAT-NI), a new {sup 99m}Tc complex comprising the nitroimidazole ligand, 2,10-dimercapto-2,10-dimethyl-4,8-diaza-6-[4-(2-nitroimidazolyl)butyl]undecane, in a low-flow in vivo model of myocardial ischaemia in thoracotomised rats. To elucidate the influence of the 2-nitroimidazole group on ischaemia-induced uptake, comparisons with ligand derivatives were performed where (a) the 2-nitro group was deleted [{sup 99m}TcO(BAT-I)], (b) the 2-nitroimidazole functionality was replaced by a Br atom [{sup 99m}TcO(BAT-Br)] and (c) the {sup 99m}TcO(BAT) moiety was replaced by an iodine-125 iodophenoxybutyl ligand ({sup 125}IP-NI). The radiolabelled compounds were i.v. injected 15 min after reducing resting myocardial blood flow by 50-60% and the uptake of radioactivity was assessed 90 min post injection. Autoradiography of left ventricular short-axis slices showed median uptake ratios of ischaemic/non-ischaemic myocardium (I/N) of 3.4, 4.5 and 3.4 for {sup 99m}TcO(BAT-NI), {sup 99m}TcO(BAT-I) and {sup 99m}TcO(BAT-Br), respectively. In contrast, {sup 125}IP-NI was not preferentially taken up by ischaemic myocardium. Accumulation of {sup 99m}TcO(BAT-NI) in ischaemic heart regions was comparable to that in the liver. Biodistribution studies showed a median uptake of 0.65% ID/g of {sup 99m}TcO(BAT-NI) in ischaemic tissue and an I/N of 3.3. On planar images of the thorax and upper abdomen the ischaemic hearts were visualised faintly; the median heart to lung count ratio for {sup 99m}TcO(BAT-NI) was 1.7, and the median heart to liver count ratio was 1.0. We conclude that uptake of {sup 99m}TcO(BAT-NI) in ischaemic myocardium does not

  2. Uptake of gaseous formaldehyde onto soil surfaces: a coated-wall flow tube study

    Science.gov (United States)

    Li, Guo; Su, Hang; Li, Xin; Meusel, Hannah; Kuhn, Uwe; Pöschl, Ulrich; Shao, Min; Cheng, Yafang

    2015-04-01

    Gaseous formaldehyde (HCHO) is an important intermediate molecule and source of HO2 radicals. However, discrepancies exist between model simulated and observed HCHO concentrations, suggesting missing sources or sinks in the HCHO budget. Multiphase processes on the surface of soil and airborne soil-derived particles have been suggested as an important mechanism for the production/removal of atmospheric trace gases and aerosols. In this work, the uptake of gaseous HCHO on soil surfaces were investigated through coated-wall flow tube experiments with HCHO concentration ranging from 10 to 40 ppbv. The results show that the adsorption of HCHO occurred on soil surfaces, and the uptake coefficient dropped gradually (i.e., by a factor of 5 after 1 hour) as the reactive surface sites were consumed. The HCHO uptake coefficient was found to be affected by the relative humidity (RH), decreasing from (2.4 ± 0.5) × 10-4 at 0% RH to (3.0 ± 0.08) × 10-5 at 70% RH, due to competition of water molecule absorption on the soil surface. A release of HCHO from reacted soil was also detected by applying zero air, suggesting the nature of reversible physical absorption and the existence of an equilibrium at the soil-gas interface. It implies that soil could be either a source or a sink for HCHO, depending on the ambient HCHO concentration. We also develop a Matlab program to calculate the uptake coefficient under laminar flow conditions based on the Cooney-Kim-Davis method.

  3. Bioremoval of diethylketone by the synergistic combination of microorganisms and clays: uptake, removal and kinetic studies.

    Science.gov (United States)

    Quintelas, Cristina; Costa, Filomena; Tavares, Teresa

    2013-03-01

    The performance of two bacteria, Arthrobacter viscosus and Streptococcus equisimilis, and the effect of the interaction of these bacteria with four different clays on the retention of diethylketone were investigated in batch experiments. The uptake, the removal percentages and the kinetics of the processes were determined. S. equisimilis, by itself, had the best performance in terms of removal percentage, for all the initial diethylketone concentrations tested: 200, 350 and 700 mg/L. The uptake values are similar for both bacteria. A possible mechanism to explain the removal of diethylketone includes its degradation by bacteria, followed by the adsorption of the intermediates/sub-products by the functional groups present on the cells' surfaces. The assays performed with bacteria and clays indicated that the uptake values are similar despite of the clay used, for the same microorganism and mass of clay, but in general, higher values are reached when S. equisimilis is used, compared to A. viscosus. Kinetic data were described by pseudo-first- and pseudo-second-order models.

  4. A cluster randomised feasibility study of an adolescent incentive intervention to increase uptake of HPV vaccination.

    Science.gov (United States)

    Forster, Alice S; Cornelius, Victoria; Rockliffe, Lauren; Marlow, Laura Av; Bedford, Helen; Waller, Jo

    2017-08-22

    Uptake of human papillomavirus (HPV) vaccination is suboptimal among some groups. We aimed to determine the feasibility of undertaking a cluster randomised controlled trial (RCT) of incentives to improve HPV vaccination uptake by increasing consent form return. An equal-allocation, two-arm cluster RCT design was used. We invited 60 London schools to participate. Those agreeing were randomised to either a standard invitation or incentive intervention arm, in which Year 8 girls had the chance to win a £50 shopping voucher if they returned a vaccination consent form, regardless of whether consent was provided. We collected data on school and parent participation rates and questionnaire response rates. Analyses were descriptive. Six schools completed the trial and only 3% of parents opted out. The response rate was 70% for the girls' questionnaire and 17% for the parents'. In the intervention arm, 87% of girls returned a consent form compared with 67% in the standard invitation arm. The proportion of girls whose parents gave consent for vaccination was higher in the intervention arm (76%) than the standard invitation arm (61%). An RCT of an incentive intervention is feasible. The intervention may improve vaccination uptake but a fully powered RCT is needed.British Journal of Cancer advance online publication: 22 August 2017; doi:10.1038/bjc.2017.284 www.bjcancer.com.

  5. Comparative studies on uptake and translocation of labelled dimethoate and methamidophos by means of systemic and local bibitors

    Energy Technology Data Exchange (ETDEWEB)

    Richter, S. (Karl-Marx-Universitaet, Leipzig (German Democratic Republic)); Dedek, W. (Akademie der Wissenschaften der DDR, Leipzig. Forschungsstelle fuer Chemische Toxikologie)

    1983-01-01

    Uptake, mobility and translocation of /sup 14/C-dimethoate and /sup 32/P-methamidophos in Vicia faba L. and Oryza sativa L. were studied by means of pea aphid (Acyrthosiphon pisum Harris), red spider mite (Tetranychus urticae Koch) and rice cicada (Sogatodes orizicola Muir). A relationship was found to exist between the uptake of active ingredients and the individual developmental stages. Both ingredients are rapidly taken up through the roots and translocated throughout the plant, the rate of incorporation being higher with mites - due to the higher share of active ingredients in their cells - than with aphids. Tests without allowing time for exposition are possible and provide direct information on the rate of uptake. Both dimethoate and methamidophos penetrate into the leaf tissue. The phloem is loaded somewhat more slowly, the rate of load being more favourable with dimethoate. Acropetal and basipetal translocation proceed accordingly. However, the two active ingredients under review are not transported in insecticidal or acaricidal concentrations. Unlike dimethoate, the insecticidal action of methamidophos in field bean persists for 20 days or more. Studies on the mobility of dimethoate in rice plants point to a high apoplastic translocation in the treated leaf and to a somewhat retarded acropetal translocation in insecticidal concentrations. These results show that bioassays may be carried out not only with aphids but also with spider mites and cicades to demonstrate the mobility of chemical agents in plants.

  6. Fast method for multielemental analysis of plants and discrimination according to the anatomical part by total reflection X-ray fluorescence spectrometry.

    Science.gov (United States)

    De la Calle, Inmaculada; Costas, Marta; Cabaleiro, Noelia; Lavilla, Isela; Bendicho, Carlos

    2013-05-01

    Fast and reliable analytical methodologies are required for quality control of plants in order to assure human health. Ultrasound-assisted extraction in combination with total reflection X-ray fluorescence is proposed as a fast and simple method for multielemental analysis of plants on a routine basis. For this purpose, five certified reference materials have been analysed for the determination of P, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn and Pb. Different extractant media (acids and oxidants) were tried. A mixture of diluted HNO(3)+HCl+HF, was selected as the best option for the achievement of complete extractions. Accurate and precise results can be reached in most cases along with a high sample throughput. Different plants (i.e., herbs, spices and medicinal plants) were analysed. Linear discriminant analysis together with the elemental concentrations allowed the differentiation of commercial preparations corresponding to flower, fruit and leaf.

  7. Colloidal gold-loaded, biodegradable, polymer-based stavudine nanoparticle uptake by macrophages: an in vitro study

    Directory of Open Access Journals (Sweden)

    Basu S

    2012-12-01

    Full Text Available Sumit Basu,1,2 Biswajit Mukherjee,1 Samrat Roy Chowdhury,1 Paramita Paul,1 Rupak Choudhury,3 Ajeet Kumar,1 Laboni Mondal,1 Chowdhury Mobaswar Hossain,1 Ruma Maji11Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India; 2Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, USA; 3Department of Biochemistry, Ballygunge Science College, Kolkata, IndiaObjective: We describe the development, evaluation, and comparison of colloidal gold-loaded, poly(d,l-lactic-co-glycolic acid-based nanoparticles containing anti-acquired immunodeficiency syndrome drug stavudine and uptake of these nanoparticles by macrophages in vitro.Methods: We used the following methods in this study: drug-excipient interaction by Fourier transform infrared spectroscopy, morphology of nanoparticles by field-emission scanning electron microscopy, particle size by a particle size analyzer, and zeta potential and polydispersity index by a zetasizer. Drug loading and in vitro release were evaluated for formulations. The best formulation was incorporated with fluorescein isothiocyanate. Macrophage uptake of fluorescein isothiocyanate nanoparticles was studied in vitro.Results: Variations in process parameters, such as speed of homogenization and amount of excipients, affected drug loading and the polydispersity index. We found that the drug was released for a prolonged period (over 63 days from the nanoparticles, and observed cellular uptake of stavudine nanoparticles by macrophages.Conclusion: Experimental nanoparticles represent an interesting carrier system for the transport of stavudine to macrophages, providing reduced required drug dose and improved drug delivery to macrophages over an extended period. The presence of colloidal gold in the particles decreased the drug content and resulted in comparatively faster drug release.Keywords: stavudine, poly(d,l-lactic-co-glycolic acid, nanoparticles

  8. Geographic and socio-demographic differences in uptake of population-based screening for atrial fibrillation: The STROKESTOP I study.

    Science.gov (United States)

    Engdahl, Johan; Holmén, Anders; Svennberg, Emma; Friberg, Leif; Frykman-Kull, Viveka; Al-Khalili, Faris; Rosenqvist, Mårten; Strömberg, Ulf

    2016-11-01

    The rationale behind screening for atrial fibrillation (AF) is to prevent ischemic stroke. Socio-demographic differences are expected to affect screening uptake. Geographic differences may provide further insights leading to targeted interventions for improved uptake. The objective of this study was to evaluate geographic and socio-demographic differences in uptake of AF screening in the population-based study STROKESTOP I. STROKESTOP was carried out in two Swedish counties with a total population of 2.3 million inhabitants. Half of the residents aged 75-76years were randomized to the screening arm: invitation to clinical examination followed by ambulant ECG recording. Information on each invited person's residential parish (n=157) was used. On parish-level, aggregated data for the participants and non-participants, respectively, were obtained with respect to socioeconomic variables: educational level, disposable income, immigrant and marital status. Geo-maps displaying participation ratios were estimated by hierarchical Bayes methods. The overall participation rate was similar in men and women but lower in Stockholm, 47.6% (5665/11,903) than in Halland, 61.2% (1495/2443). Participation was clearly associated with the socioeconomic variables. Participation not taking into account socioeconomy varied more markedly across the parishes in the Stockholm county (range: 0.65-1.26) than in the Halland county (0.94-1.27). After adjustment for socioeconomic variables, a geographic variation remained in Stockholm, but not in Halland. Participation in AF screening varied according to socioeconomic conditions. Geographic variation in participation was marked in the Stockholm county, with only one screening clinic. Geo-mapping of participation yielded useful information needed to intervene for improved screening uptake. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. A Comparative Study of 99mTc-YIGSR and 99mTc-MIBI Uptake in Tumor Cells

    Institute of Scientific and Technical Information of China (English)

    HU Jia; LAN Xiaoli; ZHANG Yongxue; GAO Zairong; WU Jun

    2005-01-01

    To investigate a new kind of tumor tracer 99mTc-YIGSR developed from a five amino structure (YIGSR) of the Laminin -chain,which can bind to the laminin receptors of tumor specifically, and radiolabeled with MAG3. (1) Preparation of the 99m Tc-YIGSR probe: with S-Acetly-NH3-MAG3as the chelator and with proper reductants YIGSR was labeled with 99mTc; (2) Cell culture and viability measurement: EAC was maintained in RPMI 1640 supplemented with calf serum; the trypan blue exclusion was applied to calculate the cell viability; (3) Study of the cell dynamic: The EACs uptake of 99mTc-YIGSR and99mTc-MIBI was observed at 37 ℃ and 22 ℃, respectively. (1)The labeling efficiencies of 99mTc-YIGSR and99mTc-MIBI were (62±3) % and (96±2) %, respectively; (2) The cell viability was declined with time of incubation; (3) At 37 ℃, the EACS uptake of 99mTc-YIGSR and99mTc-MIBI reached the peak of (43. 16±2.4) % and (24.4±1.8) % at 60min, respectively; and at 22 ℃, the highest uptake was (26.5±2.1) % and (9. 47±1.9) % at 60min, respectively. The in vitro study suggests that 99mTc-YIGSR is superior to 99mTc-MIBI in cell uptake and has potential value in tumor imaging.

  10. Multi-elemental Gd, Eu, Sm, Nd isotope ratio measurements by liquid chromatography coupled to MC-ICPMS with variable Faraday cup configurations during elution.

    Science.gov (United States)

    Guéguen, Florence; Nonell, Anthony; Isnard, Hélène; Vio, Laurent; Chartier, Frédéric

    2017-01-01

    The high-precision isotopic characterization of actinides and fission products in nuclear samples is fundamental for various applications such as the management of spent nuclear fuel or the validation of neutronic calculation codes. However multi-elemental isotope ratio measurements by mass spectrometric techniques are hampered by the presence of both spectral and non-spectral interferences as complex sample matrices are encountered in such topics, but also due to the lack of high precision mass spectrometers able to cover the entire mass spectrum. This work describes a new LC-MC-ICPMS approach allowing simultaneous high-precision and multi-elemental isotope ratio measurements of four fission products of interest for nuclear issues (Nd, Sm, Eu, Gd) within a single elution run. Variable motorized Faraday cup configurations were successively used during a specifically designed elution procedure in order to take into account the non-natural Nd, Sm, Eu, Gd isotopic compositions encountered in irradiated nuclear samples. This new method, involving the relevant isotopic reference standard injection timings for on-line mass bias corrections, was validated by the analysis of a simulated fission product fraction from a (235)U-irradiated target. Reproducibilities better than 2‰ (k=2), comparable to those obtained by off-line measurements and the classic sample-standard bracketing mass bias correction approach, were obtained for all isotope ratios, except those involving isotopes with a transient signal peak apex lower than 100mV, for which the reproducibilities were comprised between 2‰ and 6‰.

  11. Identifying factors to improve oral cancer screening uptake: a qualitative study.

    Directory of Open Access Journals (Sweden)

    Fatemeh Vida Zohoori

    Full Text Available AIMS: To engage with high risk groups to identify knowledge and awareness of oral cancer signs and symptoms and the factors likely to contribute to improved screening uptake. METHODS: Focus group discussions were undertaken with 18 males; 40+ years of age; smokers and/or drinkers (15+ cigarettes per day and/or 15+ units of alcohol per week, irregular dental attenders living in economically deprived areas of Teesside. RESULTS: There was a striking reported lack of knowledge and awareness of oral cancer and its signs and symptoms among the participants. When oral/mouth cancer leaflets produced by Cancer Research UK were presented to the participants, they claimed that they would seek help on noticing such a condition. There was a preference to seek help from their general practitioner rather than their dentist due to perceptions that a dentist is 'inaccessible' on a physical and psychological level, costly, a 'tooth specialist' not a 'mouth specialist', and also not able to prescribe medication and make referrals to specialists. Interestingly, none of the 18 participants who were offered a free oral cancer examination at a dental practice took up this offer. CONCLUSIONS: The uptake of oral cancer screening may be improved by increasing knowledge of the existence and signs and symptoms of oral cancer. Other factors that may increase uptake are increased awareness of the role of dentists in diagnosing oral cancer, promotion of oral cancer screening by health professionals during routine health checks, and the use of a "health" screening setting as opposed to a "dental" setting for such checks.

  12. Experimental study on copper uptake capacity in the Mediterranean mussel (Mytilus galloprovincialis).

    Science.gov (United States)

    Baltas, H; Dalgic, G; Bayrak, E Y; Sirin, M; Cevik, U; Apaydin, G

    2016-06-01

    To investigate the effect of different sizes, sex, and exposure time on Cu uptake capacity, mussels Mytilus galloprovincialis of different shell sizes were exposed to different Cu concentrations in different aquariums. In another experiment, mussels were exposed to stable dissolved Cu for 6 days in the laboratory. All mussels tissue concentrations were analyzed using energy dispersive X-ray fluorescence (EDXRF) spectrometry. At the end of uptake, the rate of increase of Cu level in the soft tissues of mussels in different aquariums was 3.84-7.92 times higher than before exposure. While the results of Cu concentrations were negatively correlated with the shell sizes in the control and second groups (r control = -0.862, r second = -0.851 p  0.05). Also, results showed no significant difference between male and female (p > 0.05). On the other hand, Cu concentration values in soft tissue were monitored daily and observed to be increasing up to the third day but afterwards to be descending, thus indicating a significant effect of the exposure time-related Cu uptake by mussels. Therefore, the exposure time to Cu metal of the mussel should be taken into account in the marine pollution investigations. In addition, by using the obtained Cu heavy metal concentration results, the heavy metal intake by the human population was calculated by taking into account daily mussel consumption. The results were examined for potential human health risks and discussed. These results would be helpful to understand factors controlling Cu accumulation in mussels.

  13. Mathematical modelling study for water uptake of steadily growing plant root

    Science.gov (United States)

    Chu, Jiaqing; Jiao, Weiping; Xu, Jianjun

    2008-02-01

    The root system of plant is a vitally important organ for living plant. One of the major functions of the root system is uptaking water and nutrients from the soil. The present paper analyzes the whole process of water uptake from soil by a steadily growing plant with a single slender root. We start from the basic principles of physics and fluid-dynamics, consider the structure characteristics of the water transport channel formed by the tiny xylems tubes inside plant, and establish a simplified coherent mathematical model to describe the water transport in the complete system consisting of soil, individual plant, including root, stem and leaves-atmosphere, on the basis of the plant physiology. Moreover, we resolve the proposed mathematical model for a simple artificial plant model under a variety of conditions, in terms of the numerical approach as well as analytical approach. It is shown that the results obtained by both approaches are in very good agreement; the theoretical predictions are qualitatively consistent with the practical experiences very well. The simplified mathematical model established in the present paper may provide a basis for the further investigations on the more sophisticated mathematical model.

  14. Mathematical modelling study for water uptake of steadily growing plant root

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The root system of plant is a vitally important organ for living plant. One of the major functions of the root system is uptaking water and nutrients from the soil. The present paper analyzes the whole process of water uptake from soil by a steadily growing plant with a single slender root. We start from the basic principles of physics and fluid-dynamics, consider the structure characteristics of the water transport channel formed by the tiny xylems tubes inside plant, and establish a simplified coherent mathematical model to describe the water transport in the complete system consisting of soil, individual plant, including root, stem and leaves-atmosphere, on the basis of the plant physiology. Moreover, we resolve the proposed mathematical model for a simple artificial plant model under a variety of conditions, in terms of the numerical approach as well as analytical approach. It is shown that the results obtained by both approaches are in very good agreement; the theoretical predictions are qualitatively consistent with the practical experi-ences very well. The simplified mathematical model established in the present pa-per may provide a basis for the further investigations on the more sophisticated mathematical model.

  15. Carbon uptake sensitivity of the North Atlantic to climate change: A model study with the Bergen Climate Model

    Science.gov (United States)

    Goris, Nadine; Heinze, Christoph; Tjiputra, Jerry; Schwinger, Jörg

    2015-04-01

    The efficiency of the world's oceans to take up carbon is expected to decrease with ongoing climate change, thereby increasing the atmospheric burden of carbon. Here, the North Atlantic is a region of special interest as it is one of the most important oceanic carbon sinks, featuring an exceptionally high column inventory of anthropogenic CO2. Several model studies have identified the carbon uptake of the North Atlantic as highly sensitive to climate change, but these studies are mostly global studies and are not concerned with a detailed attribution of the underlying mechanisms and their regional differences within the North Atlantic. Yet, quantifying the climate change induced CO2-uptake variability in the North Atlantic and identifying its main drivers is of high relevance for improving climate projections. In order to assess and understand the climate sensitivity of the CO2 uptake of the North Atlantic, we investigate the differences between two simulations (denoted as simulation COU and simulation BGC) carried out with the Bergen Earth System Model (BCM-C). While simulation COU features rising atmospheric CO2 concentrations (based on observed records for 1850-1999 and the IPCC SRES-A2 scenario for 2000-2099) for radiation code and carbon fluxes, simulation BGC uses rising atmospheric concentrations only for the calculation of the carbon fluxes. The differences between those simulations identify climate induced changes. Our analysis confirms the important role of the North Atlantic for carbon uptake and demonstrates that this region is most sensitive to climate change (in comparison to other oceanic regions as defined in Tjiputra et al., 2010). We furthermore identify substantially different responses to climate change in different parts of the North Atlantic. Based on these differing responses, we divide the North Atlantic into 3 regions, namely the subpolar gyre region (SPG), the high latitude region (HL) and the rest of the North Atlantic (rNAT*, covering

  16. New procedure for multielemental speciation analysis of five toxic species: As(III), As(V), Cr(VI), Sb(III) and Sb(V) in drinking water samples by advanced hyphenated technique HPLC/ICP-DRC-MS.

    Science.gov (United States)

    Marcinkowska, Monika; Komorowicz, Izabela; Barałkiewicz, Danuta

    2016-05-12

    Analytical procedure dedicated for multielemental determination of toxic species: As(III), As(V), Cr(VI), Sb(III) and Sb(V) in drinking water samples using high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-DRC-MS) technique was developed. Optimization of the detection and separation conditions was conducted. Dynamic reaction cell (DRC) with oxygen as a reaction gas was involved in the experiments. Obtained analytical signals for species separation were symmetrical, as studied by anion-exchange chromatography. Applied mobile phase consisted of 3 mM of EDTANa2 and 36 mM of ammonium nitrate. Full separation of species in the form of the following forms: H3AsO3, H2AsO4(-), SbO2(-), Sb(OH)6(-), CrO4(2-) was achieved in 15 min with use of gradient elution program. Detailed validation of analytical procedure proved the reliability of analytical measurements. The procedure was characterized by high precision in the range from 1.7% to 2.4%. Detection limits (LD) were 0.067 μg L(-1), 0.068 μg L(-1), 0.098 μg L(-1), 0.083 μg L(-1) and 0.038 μg L(-1) for As(III), As(V), Cr(VI), Sb(III) and Sb(V), respectively. Obtained recoveries confirmed the lack of interferences' influence on analytical signals as their values were in the range of 91%-110%. The applicability of the proposed procedure was tested on drinking water samples characterized by mineralization up to 650 mg L(-1).

  17. Thyroid Scan and Uptake

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ... the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is a ...

  18. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses ... the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is a ...

  19. Thyroid Scan and Uptake

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Thyroid Scan and Uptake Thyroid scan and uptake uses small ... Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is a type ...

  20. Linkages between ocean circulation, heat uptake and transient warming: a sensitivity study

    Science.gov (United States)

    Pfister, Patrik; Stocker, Thomas

    2016-04-01

    Transient global warming due to greenhouse gas radiative forcing is substantially reduced by ocean heat uptake (OHU). However, the fraction of equilibrium warming that is realized in transient climate model simulations differs strongly between models (Frölicher and Paynter 2015). It has been shown that this difference is not only related to the magnitude of OHU, but also to the radiative response the OHU causes, measured by the OHU efficacy (Winton et al., 2010). This efficacy is strongly influenced by the spatial pattern of the OHU and its changes (Rose et al. 2014, Winton et al. 2013), predominantly caused by changes in the Atlantic meridional overturning circulation (AMOC). Even in absence of external greenhouse gas forcing, an AMOC weakening causes a radiative imbalance at the top of the atmosphere (Peltier and Vettoretti, 2014), inducing in a net warming of the Earth System. We investigate linkages between those findings by performing both freshwater and greenhouse gas experiments in an Earth System Model of Intermediate Complexity. To assess the sensitivity of the results to ocean and atmospheric transport as well as climate sensitivity, we use an ensemble of model versions, systematically varying key parameters. We analyze circulation changes and radiative adjustments in conjunction with traditional warming metrics such as the transient climate response and the equilibrium climate sensitivity. This aims to improve the understanding of the influence of ocean circulation and OHU on transient climate change, and of the relevance of different metrics for describing this influence. References: Frölicher, T. L. and D.J. Paynter (2015), Extending the relationship between global warming and cumulative carbon emissions to multi-millennial timescales, Environ. Res. Lett., 10, 075022 Peltier, W. R., and G. Vettoretti (2014), Dansgaard-Oeschger oscillations predicted in a comprehensive model of glacial climate: A "kicked" salt oscillator in the Atlantic, Geophys. Res

  1. Facilitators and barriers to uptake and adherence to lifelong antiretroviral therapy among HIV infected pregnant women in Uganda: a qualitative study

    National Research Council Canada - National Science Library

    Esther Buregyeya; Rose Naigino; Aggrey Mukose; Fred Makumbi; Godfrey Esiru; Jim Arinaitwe; Joshua Musinguzi; Rhoda K Wanyenze

    2017-01-01

    ... (PMTCT) in line with the WHO 2012 guidelines. This study explored experiences of HIV infected pregnant and breastfeeding women regarding barriers and facilitators to uptake and adherence to lifelong ART...

  2. Polymeric beads containing Cyanex 923 for actinide uptake from nitric acid medium: Studies with uranium and plutonium.

    Science.gov (United States)

    Gujar, R B; Lakshmi, D Shanthana; Figoli, A; Mohapatra, P K

    2013-08-30

    Conventional phase inversion technique has been successfully applied for the preparation of the solid phase extractant (SPE), Cyanex 923 loaded polymer beads. Two types of polymer beads prepared by blending Polyetherether ketone with card (PEEKWC)/DMF with 5% Cyanex 923 (SPE-I, av bead size: 900μm) and 10% Cyanex 923(SPE-II, av. bead size: 1100μm) were evaluated for the uptake of actinide ions. The polymer beads were characterized by various physical methods such as thermal analysis, surface morphology analysis by SEM, EDAX techniques, etc. The polymer beads were used for the experiments involving the uptake of both U(VI) and Pu(IV) at tracer scale and U(VI) at milli molar concentrations from nitric acid feeds. The actinide ion uptake studies involved kinetics of metal ion sorption, adsorption isotherms, and column studies. The metal sorption capacities for U(VI) at 3M HNO3 were found to be 38.8±1.9mg and 54.5±1.7mg per g of SPE-I and SPE-II, respectively. The sorption isotherm analysis with Langmuir, D-R and Freundlisch isotherms indicated chemisorption monolayer mechanism. Column studies were also carried out using 4.5mL bed volume columns containing about 0.4 and 0.45g of SPE-I and SPE-II, respectively. The breakthrough profiles were obtained for U(VI) and the elution profiles were obtained using 1M Na2CO3 as the eluent.

  3. Hydroponics versus field lysimeter studies of urea, ammonium and nitrate uptake by oilseed rape (Brassica napus L.).

    Science.gov (United States)

    Arkoun, Mustapha; Sarda, Xavier; Jannin, Laëtitia; Laîné, Philippe; Etienne, Philippe; Garcia-Mina, José-Maria; Yvin, Jean-Claude; Ourry, Alain

    2012-09-01

    N-fertilizer use efficiencies are affected by their chemical composition and suffer from potential N-losses by volatilization. In a field lysimeter experiment, (15)N-labelled fertilizers were used to follow N uptake by Brassica napus L. and assess N-losses by volatilization. Use of urea with NBPT (urease inhibitor) showed the best efficiency with the lowest N losses (8% of N applied compared with 25% with urea alone). Plants receiving ammonium sulphate, had similar yield achieved through a better N mobilization from vegetative tissues to the seeds, despite a lower N uptake resulting from a higher volatilization (43% of applied N). Amounts of (15)N in the plant were also higher when plants were fertilized with ammonium nitrate but N-losses reached 23% of applied N. In parallel, hydroponic experiments showed a deleterious effect of ammonium and urea on the growth of oilseed rape. This was alleviated by the nitrate supply, which was preferentially taken up. B. napus was also characterized by a very low potential for urea uptake. BnDUR3 and BnAMT1, encoding urea and ammonium transporters, were up-regulated by urea, suggesting that urea-grown plants suffered from nitrogen deficiency. The results also suggested a role for nitrate as a signal for the expression of BnDUR3, in addition to its role as a major nutrient. Overall, the results of the hydroponic study showed that urea itself does not contribute significantly to the N nutrition of oilseed rape. Moreover, it may contribute indirectly since a better use efficiency for urea fertilizer, which was further increased by the application of a urease inhibitor, was observed in the lysimeter study.

  4. A model and experimental study of phosphate uptake kinetics in algae:Considering surface adsorption and P-stress

    Institute of Scientific and Technical Information of China (English)

    Bo Yao; Beidou Xi; Chunming Hu; Shouliang Huo; Jing Su; Hongliang Liu

    2011-01-01

    Phosphorus is an important limiting nutrient in many ecosystems. Consequently, there is increasing interest on phosphate uptake and algal growth due to the increasing frequency and magnitude of algal blooms induced by eutrophication. The co-existence of surface adsorbed and intracellular phosphorus pools indicate that phosphate uptake by phytoplankton is, to some extent, a two-stage kinetic process. However, almost all previous uptake models considered the internal uptake stage only and ignored the possible impact of surface adsorption. In this article, a two-stage kinetic uptake model considering both surface adsorption and P-stress on phosphate uptake by algae was constructed and compared to conventional one-stage models, based on experimental data on short-term uptake kinetics of a green algae S. quadricauda. Results indicated that with suitable parameters, the two-stage uptake model not only fit the experimental data better, but also gave more reasonable and realistic explanations to the phosphate uptake process. The results are meaningful as surface-adsorption of phosphate may affect the uptake process of phosphate and assist in understanding realistic phosphate uptake kinetics in phytoplankton.

  5. Uptake of silica covered Quantum Dots into living cells: Long term vitality and morphology study on hyaluronic acid biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    D' Amico, Michele [Dip. Biomedico di Medicina Interna e Specialistica, Universitá degli Studi di Palermo, Piazza delle Cliniche, 2, 90127 Palermo (Italy); Dip. di Fisica e Chimica, Universitá degli Studi di Palermo, Viale delle Scienze, Ed. 18, 90128 Palermo (Italy); Fiorica, Calogero, E-mail: calogero.fiorica@unipa.it [Dip. di Scienze e Tecnologie Molecolari e Biomolecolari, Sezione di Chimica e Tecnologie Farmaceutiche, Universitá degli Studi di Palermo, Via Archirafi, 28, 90136 Palermo (Italy); Palumbo, Fabio Salvatore [Dip. di Scienze e Tecnologie Molecolari e Biomolecolari, Sezione di Chimica e Tecnologie Farmaceutiche, Universitá degli Studi di Palermo, Via Archirafi, 28, 90136 Palermo (Italy); Militello, Valeria; Leone, Maurizio [Dip. di Fisica e Chimica, Universitá degli Studi di Palermo, Viale delle Scienze, Ed. 18, 90128 Palermo (Italy); Dubertret, Benoit [Laboratoire de Physique et d’Etude des Matèriaux, ESPCI-ParisTech, PSL Research University, Sorbonne Universitè UPMC Univ. Paris 06, CNRS, 10 rue Vauquelin, 75005 Paris (France); Pitarresi, Giovanna; Giammona, Gaetano [Dip. di Scienze e Tecnologie Molecolari e Biomolecolari, Sezione di Chimica e Tecnologie Farmaceutiche, Universitá degli Studi di Palermo, Via Archirafi, 28, 90136 Palermo (Italy)

    2016-10-01

    Quantum Dots (QDs) are promising very bright and stable fluorescent probes for optical studies in the biological field but water solubility and possible metal bio-contamination need to be addressed. In this work, a simple silica-QD hybrid system is prepared and the uptake in bovine chondrocytes living cells without any functionalization of the external protective silica shield is demonstrated. Moreover, long term treated cells vitality (up to 14 days) and the transfer of silica-QDs to the next cell generations are here reported. Confocal fluorescence microscopy was also used to determine the morphology of the so labelled cells and the relative silica-QDs distribution. Finally, we employ silica-QD stained chondrocytes to characterize, as proof of concept, hydrogels obtained from an amphiphilic derivative of hyaluronic acid (HA-EDA-C {sub 18}) functionalized with different amounts of the RGD peptide. - Highlights: • Non functionalized silica-quantum dots fluorescent nanoparticles uptake is observed. • Morphology studies of such cells could be done by confocal fluorescence microscopy. • Labelled chondrocytes are viable until at least 14 days. • RGD functionalized Hyaluronic Acid hydrogels are studied as cell scaffolds. • Chondrocyte are promptly attached on RGD-functionalized hydrogels.

  6. Uptake of Ra during the recrystallization of barite: a microscopic and time of flight-secondary ion mass spectrometry study.

    Science.gov (United States)

    Klinkenberg, Martina; Brandt, Felix; Breuer, Uwe; Bosbach, Dirk

    2014-06-17

    A combined macroscopic and microanalytical approach was applied on two distinct barite samples from Ra uptake batch experiments using time of flight-secondary ion mass spectrometry (ToF-SIMS) and detailed scanning electron microscopy (SEM) investigations. The experiments were set up at near to equilibrium conditions to distinguish between two possible scenarios for the uptake of Ra by already existent barite: (1) formation of a Ba1-xRaxSO4 solid solution surface layer on the barite or (2) a complete recrystallization, leading to homogeneous Ba1-xRaxSO4 crystals. It could be clearly shown that Ra uptake in all barite particles analyzed within this study is not limited to the surface but extends to the entire solid. For most grains a homogeneous distribution of Ra could be determined, indicating a complete recrystallization of barite into a Ba1-xRaxSO4 solid solution. The maxima of the Ra/Ba intensity ratio distribution histograms calculated from ToF-SIMS are identical with the expected Ra/Ba ratios calculated from mass balance assuming a complete recrystallization. In addition, the role of Ra during the recrystallization of barite was examined via detailed SEM investigations. Depending on the type of barite used, an additional coarsening effect or a strong formation of oriented aggregates was observed compared to blank samples without Ra. In conclusion, the addition of Ra to a barite at close to equilibrium conditions has a major impact on the system leading to a fast re-equilibration of the solid to a Ba1-xRaxSO4 solid solution and visible effects on the particle size distribution, even at room temperature.

  7. Design, synthesis and SAR studies of GABA uptake inhibitors derived from 2-substituted pyrrolidine-2-yl-acetic acids.

    Science.gov (United States)

    Steffan, Tobias; Renukappa-Gutke, Thejavathi; Höfner, Georg; Wanner, Klaus T

    2015-03-15

    In this paper, we disclose the design and synthesis of a series of 2-substituted pyrrolidine-2-yl-acetic acid as core structures and the N-arylalkyl derivatives thereof as potential GABA transport inhibitors. The 2-position in the side chain of pyrrolidine-2-yl-acetic acid derivatives was substituted with alkyl, hydroxy and amino groups to modulate the activity and selectivity to mGAT1 and mGAT4 proteins. SAR studies of the compounds performed for the four mouse GABA transporter proteins (mGAT1-mGAT4) implied significant potencies and subtype selectivities for 2-hydroxy-2-pyrrolidine-2-yl-acetic acid derivatives. The racemate rac-(u)-13c exhibited the highest potency (pIC50 5.67) at and selectivity for mGAT1 in GABA uptake assays. In fact, the potency of rac-(u)-13c at hGAT-1 (pIC50 6.14) was even higher than its potency at mGAT1. These uptake results for rac-(u)-13c are in line with the binding affinities to the aforesaid proteins mGAT1 (pKi 6.99) and hGAT-1 (pKi 7.18) determined by MS Binding Assay based on NO711 as marker quantified by LC-ESI-MS-MS analysis. Interestingly, the 2-hydroxy-2-pyrrolidine-2-yl-acetic acid rac-(u)-13d containing 2-{[tris(4-methoxyphenyl)]methoxy} ethyl group at the nitrogen atom of the pyrrolidine ring showed high potency at mGAT4 and a comparatively better selectivity for this protein (>15 against mGAT3) than the well known mGAT4 uptake inhibitor (S)-SNAP-5114.

  8. A Study on Potentiality of Carbon Storage and CO2 Uptake in the Biomass and Soil of Coppice Stand

    Directory of Open Access Journals (Sweden)

    A. Khademi

    2009-01-01

    Full Text Available Problem statement: Enhancing carbon storage in terrestrial ecosystems, especially in the forests, is a key factor in maintaining the atmosphere's carbon balance. With regard to the importance of forest in carbon sequestration, this study attempted to investigate the carbon storage potential and CO2 uptake in oak coppice stand. Approach: After combining slope, aspect and hypsometric maps, the number of land units (polygons as well as their areas were determined. Then 60 sample trees were selected in such a way that all environmental and typological conditions were taken into account. After determining the overall weight of different parts of tree, to measure the dry weight as well as to determine the amount of biomass, different parts of tree were transformed to a kiln. The humus was collected and weighted in an area of 400 cm2 under each tree. The quantity of ash was taken away from biomass, then the amount of organic sequestrated carbon as well as that of CO2 uptake was measured. To determine the amount of carbon stored in the soil samples were extracted from the depths of 0-10 and 10-30 cm. Results: The amount of organic sequestrated carbon was 22.65 tons ha-1. The trunk, root, branch, soil, leaf and humus had the maximal amount of storage respectively. The annual carbon dioxide uptake was 5.94 tons ha-1. Conclusion: Coppice stands had massive plant coverage as well as an increase in biomass production if the destructive factors were removed from these areas.

  9. Studies on Ailanthus altissima cell suspension cultures. Uptake of L-[methyl-(14)C]methionine and incorporation of label into 1-methoxycanthin-6-one.

    Science.gov (United States)

    Anderson, L A; Hay, C A; Phillipson, J D; Roberts, M F

    1987-06-01

    Time-course studies of the uptake of L-[methyl (14)C]-methionine have shown rapid uptake by Ailanthus altissima cells when fed at weekly stages throughout the growth cycle. The radio-label from [(14)C]-methionine was shown to be incorporated into 1-methoxycanthin-6-one with the highest level of incorporation being achieved with cells fed late in the growth phase.

  10. 18F-fluorodeoxyglucose and PET/CT for noninvasive study of exercise-induced glucose uptake in rat skeletal muscle and tendon

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Kjaer, Michael; El-Ali, Henrik

    2009-01-01

    PURPOSE: To investigate exercise-related glucose uptake in rat muscle and tendon using PET/CT and to study possible explanatory changes in gene expression for the glucose transporters (GLUT1 and GLUT4). METHODS: The sciatic nerve in eight Wistar rats was subjected to electrostimulation to cause...... rats were cut out and scanned separately (distance>or=1 cm). RESULTS: Muscle contractions increased glucose uptake approximately sevenfold in muscles (pGLUT4 were expressed...... and GLUT4....

  11. A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

    Science.gov (United States)

    Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

    2008-08-01

    The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial ∘Bé densities as compared with higher initial ∘Bé densities.

  12. Determinants of Cervical Cancer Screening Uptake among Women in Ilorin, North Central Nigeria: A Community-Based Study

    Directory of Open Access Journals (Sweden)

    Ajibola Idowu

    2016-01-01

    Full Text Available Introduction. Cancer of the cervix is the leading cause of cancer deaths among women in developing countries. Screening is one of the most cost effective control strategies for the disease. This study assessed the determinants of cervical cancer screening uptake among Nigerian women. Methodology. This cross-sectional study was conducted using multistage sampling technique among 338 participants in Ilorin, North Central Nigeria. A pretested questionnaire was used for data collection and data analysis was done using SPSS version 21. Chi-square test was used for bivariate analysis while binary logistic regression was used for multivariate analysis. Statistical significance was set at p<0.05. Results. Only 8.0% of the respondents had ever been screened for cancer of the cervix. The proportion of women who had ever been screened was significantly higher among those who demonstrated positive attitude to screening (81.5%, p=0.001, respondents who were aware of the disease (100.0%, p=0.001, and those who were aware of cervical cancer screening (88.9%, p=0.001. Respondents who had negative attitude had 63% lesser odds of being screened compared to those who had positive attitudes towards screening (AOR; 0.37, 95% CI; 0.01–0.28. Conclusion. There is urgent need to improve the knowledge base and attitude of Nigerian women to enhance cervical cancer screening uptake among them.

  13. Study of 223Ra uptake mechanism by Fe3O4 nanoparticles: towards new prospective theranostic SPIONs

    Science.gov (United States)

    Mokhodoeva, Olga; Vlk, Martin; Málková, Eva; Kukleva, Ekaterina; Mičolová, Petra; Štamberg, Karel; Šlouf, Miroslav; Dzhenloda, Rustam; Kozempel, Ján

    2016-10-01

    The use of superparamagnetic iron oxide nanoparticles ( SPIONs) and radiolabelled nanoparticles ( NPs) has grown considerably over the recent years, and the SPIONs labelled with medicinal radionuclides offer new opportunities in multimodal diagnostics and in the drug-delivery systems for targeted alpha-particle therapy (TAT) driven by magnetic field gradient or by biologically active moieties bound on NPs shell. However, the mechanisms of NPs radiolabelling are not studied substantially and still remain unclear, even though the way of label attachment directly implies the stability of the label-nanoparticle construct. Since the 223Ra was the first clinically approved alpha-emitter, it is a promising nuclide for further development of its targeted carriers. We report here on the study of 223Ra uptake by the Fe3O4 SPIONs, together with an attempt to propose the 223Ra uptake mechanism by the Fe3O4 NPs in the presence of a phosphate buffer a typical formulation medium, under the pseudo-equilibrium conditions. Further, the in vitro stability tests of the prepared [223Ra]Fe3O4 NPs were performed to estimate the 223Ra label stability. The potential use of 223Ra-labelled SPIONs in theranostic applications is also discussed.

  14. An electrochemical study of hydrogen uptake and elimination by bare and gold-plated waspaloy

    Science.gov (United States)

    Danford, M. D.; Deramus, G. E., Jr.; Lowery, J. R.

    1984-01-01

    Two electrochemical methods for the determination of hydrogen concentrations in metals are discussed and evaluated. The take-up of hydrogen at a pressure of 5000 psi by Waspaloy metal was determined experimentally at 24 C. It was found that the metal becomes saturated with hydrogen after an exposure time of about 1 hr. For samples charged with hydrogen at high pressure, most of the hydrogen is contained in the interstitial solid solution of the metal. For electrolytically charged samples, most of the hydrogen is contained as surface and subsurface hydrides. Hydrogen elimination rates were determined for these two cases, with the rate for electrolytically charged samples being greater by over a factor of two. Theoretical effects of high temperature and pressure on hydrogen take-up and elimination by bare and gold plated Waspaloy metal was considered. The breakthrough point for hydrogen at 5000 psi, determined experimentally, lies between a gold thickness of 0.0127 mm (0.0005 in.) and 0.0254 mm (0.001 in.) at 24 C. Electropolishing was found to greatly reduce the uptake of hydrogen at high pressure by Waspaloy metal at 24 C. Possible implications of the results obtained, as they apply to the turbine disk of the space shuttle main engine, are discussed.

  15. Radioiodinated meta-iodobenzylguanidine uptake in medullary thyroid cancer. A French cooperative study

    Energy Technology Data Exchange (ETDEWEB)

    Baulieu, J.L.; Guilloteau, D.; Delisle, M.J.; Perdrisot, R.; Gardet, P.; Delepine, N.; Baulieu, F.; Dupont, J.L.; Talbot, J.N.; Coutris, G.

    1987-11-01

    Fifty meta-iodobenzylguanidine (MIBG) scintiscans were performed in three groups of medullary thyroid cancer (MTC) patients. Group 1 (n = 11) included treated patients with normal calcitonin levels; Group 2 (n = 24) included patients with elevated calcitonin levels due to sporadic and isolated MTC; Group 3 (n = 15) included patients with elevated calcitonin levels due to familial MTC or multiple endocrine neoplasia Type IIA syndrome (MEN). In Group 1 three pheochromocytoma were depicted by MIBG scintiscan. In Group 2 MTC was seen in a small number of patients (3 of 24). In Group 3, besides adrenal hyperplasia and pheochromocytoma four patients, MIBG scintigraphy showed where MTC had localized and spread in almost half of patients (7 of 15). MIBG uptake occurred in patients with relatively high calcitonin level (greater than 0.6 nmol/l). These data indicate that in patients with familial MTC or MEN syndrome, MIBG scintiscan can be useful not only in detecting associated pheochromocytoma, but also in showing MTC.

  16. In-vitro cytotoxicity and cellular uptake studies of luminescent functionalized core-shell nanospheres.

    Science.gov (United States)

    Ansari, Anees A; Hasan, T N; Syed, N A; Labis, J P; Alshatwi, Ali A

    2017-09-01

    Monodispersed luminescent functionalized core-shell nanospheres (LFCSNs) were successfully synthesized and investigated for their cyto-toxic effect on human liver hepatocellular carcinoma cell line (HepG2 cells) by adopting MTT, DNA Ladder, TUNEL assay and qPCR based gene expressions through mRNA quantifications. The TUNEL and DNA ladder assays suggested an insignificant apoptosis in HepG2 cells due to the LFCSNs treatment. Further, the qPCR results also show that the mRNA expressions of cell cycle checkpoint gene p53 and apoptosis related gene (caspase-9) was up-regulated, while the antiapoptotic gene BCl-2 and apoptosis related genes FADD and CAS-3 (apoptosis effecter gene) were down-regulated in the LFCSNs treated cells. The nanospheres that were loaded into the cells confirm their intracellular uptake by light and fluorescent spectro-photometry and microscopy imaging analysis. The loaded nanospheres demonstrate an absolute resistance to photo-bleaching, which were applied for dynamic imaging to real-time tracking in-vitro cell migratory activity for continuous 24 and 48 h durations using a time-lapsed fluorescent microscope. These properties of LFCSNs could therefore promote applications in the area of fluorescent protein biolabeling and drug-delivery.

  17. Nonrecirculating hydroponic systems suitable for uptake studies at very low nutrient concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Gutschick, V.P.; Kay, L.E. (New Mexico State Univ., Las Cruces (USA))

    1991-04-01

    The authors describe the mechanical, electronic, hydraulic, and structural design of a nonrecirculating hydroponic system. The system is particularly suited to sutides at very low nutrient concentratons, for which on-line concentration monitoring methods either do not exist or are costly and limited to monitoring relatively few indivitual plants. Solutions are mised automatically to chosen concentrations, which can be set differently for every pump fed from a master supply of deionized water and nutrient concentrates. Pumping rates can be varied over a 50-fold range, up to 400 liters per day, which suffices to maintain a number of large, post-seedling plants in rapid growth at (sub)micromolar levels of N and P. The outflow of each pump is divided among as many as 12 separate root chambers. In each changer one may monitor uptake by individual plant roots or segments thereof, by measuring nutrient depletion in batch samples of solution. The system is constructed from nontoxic materials that do not adsorb nutrient ions; no transient shifts of nitrate and phosphate concentrations are observable at the submicromolar level. Nonrecirculaton of solution limits porblems of pH shifts, microbial contamination, and cumulative imbalances in unmonitored nutrients. They note several disadvantages, principally related to high consumption of deionized water and solutes. The reciprocating pumps can be constructed inexpensively, particularly by the researcher. They also report previously unattainable control of passive temperature rise of chambers exposed to full sunlight, by use of white epoxy paint.

  18. Sorptive Uptake Studies of an Aryl-Arsenical with Iron Oxide Composites on an Activated Carbon Support

    Directory of Open Access Journals (Sweden)

    Jae H. Kwon

    2014-03-01

    Full Text Available Sorption uptake kinetics and equilibrium studies for 4-hydroxy-3-nitrobenzene arsonic acid (roxarsone was evaluated with synthetic magnetite (Mag-P, commercial magnetite (Mag-C, magnetite 10%, 19%, and 32% composite material (CM-10, -19, -32 that contains granular activated carbon (GAC, and synthetic goethite at pH 7.00 in water at 21 °C for 24 h. GAC showed the highest sorptive removal of roxarsone and the relative uptake for each sorbent material with roxarsone are listed in descending order as follows: GAC (471 mg/g > goethite (418 mg/g > CM-10 (377 mg/g CM-19 (254 mg/g > CM-32 (227 mg/g > Mag-P (132 mg/g > Mag-C (29.5 mg/g. The As (V moiety of roxarsone is adsorbed onto the surface of the iron oxide/oxyhydrate and is inferred as inner-sphere surface complexes; monodentate-mononuclear, bidentate-mononuclear, and bidentate-binuclear depending on the protolytic speciation of roxarsone. The phenyl ring of roxarsone provides the primary driving force for the sorptive interaction with the graphene surface of GAC and its composites. Thus, magnetite composites are proposed as multi-purpose adsorbents for the co-removal of inorganic and organic arsenicals due to the presence of graphenic and iron oxide active adsorption sites.

  19. Single-molecule studies of oligomer extraction and uptake of dyes in poly(dimethylsiloxane) films.

    Science.gov (United States)

    Lange, Jeffrey J; Collinson, Maryanne M; Culbertson, Christopher T; Higgins, Daniel A

    2009-12-15

    Single-molecule microscopic methods were used to probe the uptake, mobility, and entrapment of dye molecules in cured poly(dimethylsiloxane) (PDMS) films as a function of oligomer extraction. The results are relevant to the use of PDMS in microfluidic separations, pervaporation, solid-phase microextraction, and nanofiltration. PDMS films were prepared by spin-casting dilute solutions of Sylgard 184 onto glass coverslips, yielding approximately 1.4 microm thick films after curing. Residual oligomers were subsequently extracted from the films by "spin extraction". In this procedure, 200 microL aliquots of isopropyl alcohol were repeatedly dropped onto the film surface and spun off at 2000 rpm. Samples extracted 5, 10, 20, and 40 times were investigated. Dye molecules were loaded into these films by spin-casting nanomolar dye solutions onto the films. Both neutral perylene diimide (N,N'-bis(butoxypropyl)perylene-3,4,9,10-tetracarboxylic diimide) and cationic rhodamine 6G (R6G) dyes were employed. The films were imaged by confocal fluorescence microscopy. The images obtained depict nonzero populations of fixed and mobile molecules in all films. Cross-correlation methods were used to quantitatively determine the population of fixed molecules in a given region, while a Bayesian burst analysis was used to obtain the total population of molecules. The results show that the total amount of dye loaded increases with increased oligomer extraction, while the relative populations of fixed and mobile molecules decrease and increase, respectively. Bulk R6G data also show greater dye loading with increased oligomer extraction.

  20. A method for comparing intra-tumoural radioactivity uptake heterogeneity in preclinical positron emission tomography studies

    Energy Technology Data Exchange (ETDEWEB)

    Grafström, Jonas; Ahlzén, Hanna-Stina [Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17177 Stockholm (Sweden); Stone-Elander, Sharon [Department of Clinical Neuroscience, Karolinska Institutet, SE-17176 Stockholm (Sweden); PET Radiochemistry, Neuroradiology Department, Karolinska University Hospital, SE-17176 Stockholm (Sweden)

    2015-09-08

    Non-uniformity influences the interpretation of nuclear medicine based images and consequently their use in treatment planning and monitoring. However, no standardised method for evaluating and ranking heterogeneity exists. Here, we have developed a general algorithm that provides a ranking and a visualisation of the heterogeneity in small animal positron emission tomography (PET) images. The code of the algorithm was written using the Matrix Laboratory software (MATLAB). Parameters known to influence the heterogeneity (distances between deviating peaks, gradients and size compensations) were incorporated into the algorithm. All data matrices were mathematically constructed in the same format with the aim of maintaining overview and control. Histograms visualising the spread and frequency of contributions to the heterogeneity were also generated. The construction of the algorithm was tested using mathematically generated matrices and by varying post-processing parameters. It was subsequently applied in comparisons of radiotracer uptake in preclinical images in human head and neck carcinoma and endothelial and ovarian carcinoma xenografts. Using the developed algorithm, entire tissue volumes could be assessed and gradients could be handled in an indirect manner. Similar-sized volumes could be compared without modifying the algorithm. Analyses of the distribution of different tracers gave results that were generally in accordance with single plane preclinical images, indicating that it could appropriately handle comparisons of targeting vs. non-targeting tracers and also for different target levels. Altering the reconstruction algorithm, pixel size, tumour ROI volumes and lower cut-off limits affected the calculated heterogeneity factors in expected directions but did not reverse conclusions about which tumour was more or less heterogeneous. The algorithm constructed is an objective and potentially user-friendly tool for one-to-one comparisons of heterogeneity in

  1. Comparative Studies on Phosphorus Uptake and Growth Kinetics of the Microalga Tetraselmis subcordiformis and the Macroalga Ulva pertusa

    Institute of Scientific and Technical Information of China (English)

    NAN Chunrong; DONG Shuanglin

    2004-01-01

    Short-term uptake experiments and long-term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate (Vspm) and the maximal growth efficiency (β), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.

  2. Comparative studies on phosphorus uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa

    Science.gov (United States)

    Nan, Chunrong; Dong, Shuanglin

    2004-04-01

    Short-term uptake experiments and long-term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate ( V {m/sp}) and the maximal growth efficiency (β), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.

  3. Mitochondrial calcium uptake.

    Science.gov (United States)

    Williams, George S B; Boyman, Liron; Chikando, Aristide C; Khairallah, Ramzi J; Lederer, W J

    2013-06-25

    Calcium (Ca(2+)) uptake into the mitochondrial matrix is critically important to cellular function. As a regulator of matrix Ca(2+) levels, this flux influences energy production and can initiate cell death. If large, this flux could potentially alter intracellular Ca(2+) ([Ca(2+)]i) signals. Despite years of study, fundamental disagreements on the extent and speed of mitochondrial Ca(2+) uptake still exist. Here, we review and quantitatively analyze mitochondrial Ca(2+) uptake fluxes from different tissues and interpret the results with respect to the recently proposed mitochondrial Ca(2+) uniporter (MCU) candidate. This quantitative analysis yields four clear results: (i) under physiological conditions, Ca(2+) influx into the mitochondria via the MCU is small relative to other cytosolic Ca(2+) extrusion pathways; (ii) single MCU conductance is ∼6-7 pS (105 mM [Ca(2+)]), and MCU flux appears to be modulated by [Ca(2+)]i, suggesting Ca(2+) regulation of MCU open probability (P(O)); (iii) in the heart, two features are clear: the number of MCU channels per mitochondrion can be calculated, and MCU probability is low under normal conditions; and (iv) in skeletal muscle and liver cells, uptake per mitochondrion varies in magnitude but total uptake per cell still appears to be modest. Based on our analysis of available quantitative data, we conclude that although Ca(2+) critically regulates mitochondrial function, the mitochondria do not act as a significant dynamic buffer of cytosolic Ca(2+) under physiological conditions. Nevertheless, with prolonged (superphysiological) elevations of [Ca(2+)]i, mitochondrial Ca(2+) uptake can increase 10- to 1,000-fold and begin to shape [Ca(2+)]i dynamics.

  4. Extensive FDG uptake and its modification with corticosteroid in a granuloma rat model: an experimental study for differentiating granuloma from tumors

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Songji; Takei, Toshiki; Zhao, Yan; Tamaki, Nagara [Graduate School of Medicine, Hokkaido University, Department of Nuclear Medicine, Sapporo (Japan); Kuge, Yuji [Graduate School of Medicine, Hokkaido University, Department of Molecular Imaging, Sapporo (Japan); Graduate School of Pharmaceutical Sciences, Kyoto University, Department of Patho-functional Bioanalysis, Kyoto (Japan); Kohanawa, Masashi [Graduate School of Medicine, Hokkaido University, Department of Microbiology, Sapporo (Japan); Takahashi, Toshiyuki [Hokkaido Gastroenterology Hospital, Department of Pathology, Sapporo (Japan); Kawashima, Hidekazu; Temma, Takashi [Graduate School of Pharmaceutical Sciences, Kyoto University, Department of Patho-functional Bioanalysis, Kyoto (Japan); Seki, Koh-ichi [Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan)

    2007-12-15

    Increased {sup 18}F-fluorodeoxyglucose (FDG) uptake in inflammatory lesions, particularly in granulomatous inflammation (e.g., sarcoidosis), makes it difficult to differentiate malignant tumors from benign lesions and is the main source of false-positive FDG-PET findings in oncology. Here, we developed a rat granuloma model and examined FDG uptake in the granuloma. The effects of corticosteroid on FDG uptake in the granuloma were compared with those in a malignant tumor. Rats were inoculated with Mycobacterium bovis bacillus Calmette-Guerin (BCG) or allogenic hepatoma cells, and subdivided into control and pretreated (methylprednisolone acetate, 8 mg/kg i.m.) groups. Radioactivity in tissues was determined 1 h after the FDG injection. FDG-PET was performed in rats bearing BCG granulomas or tumors before and after prednisolone treatment. Mature epithelioid cell granuloma-formation and massive lymphocyte-infiltration were observed in the control group of granuloma, histologically similar to sarcoidosis. The mean FDG uptake in the granuloma was comparable to that in the hepatoma. Prednisolone reduced epithelioid cell granuloma-formation and lymphocyte-infiltration. Prednisolone significantly decreased the level of FDG uptake in the granuloma (52% of control), but not in the hepatoma. The FDG uptake levels in the granulomas and tumors were clearly imaged with PET. We developed an intramuscular granuloma rat model that showed a high FDG uptake comparable to that of the tumor. The effect of prednisolone pretreatment on FDG uptake was greater in the granuloma than in the tumor. These results suggest that BCG-induced granuloma may be a valuable model and may provide a biological basis for FDG studies. (orig.)

  5. Workplace availability, risk group and perceived barriers predictive of 2016-17 influenza vaccine uptake in the United States: A cross-sectional study.

    Science.gov (United States)

    Luz, Paula M; Johnson, Riley E; Brown, Heidi E

    2017-10-13

    Seasonal influenza, though mostly self-limited in the healthy adult, may lead to severe disease and/or complications in subpopulations. Annual influenza vaccination is available in many countries with coverage goals rarely being met. We conducted a cross-sectional study of influenza vaccine uptake and explored socio-demographic, economic, and psychological factors that explained vaccine uptake. The survey was administered via Amazon Mechanical Turk (MTurk) to United States residents in January 2017, using the Qualtrics platform. Using principal axis factor analysis, we reduced the 25 items theory-based psychological determinants into the primary constructs they measure if/when internal consistency was sufficient (Cronbach's alpha >0.60). Logistic regression models were used to quantify the association of socio-demographic, economic, and psychological factors with reported vaccine behavior in the 2016-17 flu season. 1007 participants completed the survey, sex distribution was even, 67% had 25-44years of age, and 61% annual household income of $30-99 thousand United States dollars. About 25% had the flu shot offered at their workplace and 20% reported belonging to a group for whom the flu shot is recommended. Vaccine uptake was 31.5%. Eight predictors remained in the final adjusted model (R(2)=0.489), having the vaccine offered at the workplace, belonging to a group for whom the vaccine is recommended, and higher perceived barriers were the strongest predictors of vaccine uptake, increasing (and decreasing in the case of barriers) the odds by >3-fold. Additionally, higher household income, higher perceived susceptibility and higher perceived benefits also independently predicted vaccine uptake. We found evidence that perceived barriers significantly impaired vaccine uptake to the same extent that having the vaccine offered at the workplace or belonging to a group for whom the vaccine is recommended facilitated uptake. Ideally, a better understanding of drivers of

  6. Uptake of HNO3 to deliquescent sea-salt particles: a study using the short-lived radioactive isotope tracer 13N

    Directory of Open Access Journals (Sweden)

    C. Guimbaud

    2002-01-01

    Full Text Available The uptake of HNO3 to deliquescent airborne sea-salt particles (RH = 55%, P = 760 torr, T = 300 K at concentrations from 2 to 575 ppbv is measured in an aerosol flow tube using 13N as a tracer. Small particles ( 70 nm diameter are used in order to minimize the effect of diffusion in the gas phase on the mass transfer. Below 100 ppbv, an uptake coefficient (gupt of 0.50 ± 0.20 is derived. At higher concentrations, the uptake coefficient decreases along with the consumption of aerosol chloride. Data interpretation is further supported by using the North American Aerosol Inorganics Model (AIM, which predicts the aqueous phase activities of ions and the gas-phase partial pressures of H2O, HNO3, and HCl at equilibrium for the NaCl/HNO3/H2O system. These simulations show that the low concentration data are obtained far from equilibrium, which implies that the uptake coefficient derived is equal to the mass accommodation coefficient under these conditions. The observed uptake coefficient can serve as input to modeling studies of atmospheric sea-salt aerosol chemistry. The main sea-salt aerosol burden in the marine atmosphere is represented by coarse mode particles (> 1 µm diameter. This implies that diffusion in the gas-phase is the limiting step to HNO3 uptake until the sea-salt has been completely processed.

  7. Preliminary study on mercury uptake by Rosmarinus officinalis L. (Rosemary) in a mining area (Mt. Amiata, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Barghigiani, C.; Ristori, T. [Institute of Biophysics, Pisa (Italy)

    1995-04-01

    Among the different plants analyzed to assess environmental mercury contamination of mining areas, lichens are those most studied, followed by brooms together with pine, which was also used in other areas, and spruce. Other species, both naturally occurring and cultivated, have also been studied. This work reports on the results of mercury uptake and accumulation in rosemary in relation to metal concentrations in both air and soil. R. officinalis is a widespread endemic Mediterranean evergreen shrub, which in Italy grows naturally and is also cultivated as a culinary herb. This research was carried out in Tuscany (Italy), in the Mt. Amiata area, which is characterized by the presence of cinnabar (HgS) deposits and has been used for mercury extraction and smelting from Etruscan times until 1980, and in the country near the town of Pisa, 140 km away from Mt. Amiata. 16 refs., 3 figs., 1 tab.

  8. {sup 18}F-FDG uptake on PET in primary mediastinal non-thymic neoplasm: A clinicopathological study

    Energy Technology Data Exchange (ETDEWEB)

    Kaira, Kyoichi, E-mail: kkaira1970@yahoo.co.jp [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Abe, Masato [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Nakagawa, Kazuo; Ohde, Yasuhisa; Okumura, Takehiro [Division of Thoracic Surgery, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Takahashi, Toshiaki; Murakami, Haruyasu; Shukuya, Takehito; Kenmotsu, Hirotsugu; Naito, Tateaki [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Hayashi, Isamu [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Oriuchi, Noboru [Department of Diagnostic Radiology and Nuclear medicine, Gunma University Graduate School of Medicine, Showa-machi, Maebashi 371-8511, Gunma (Japan); Endo, Masahiro [Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Kondo, Haruhiko [Division of Thoracic Surgery, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Nakajima, Takashi [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Yamamoto, Nobuyuki [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan)

    2012-09-15

    Background: The usefulness of 2-[{sup 18}F]-fluoro-2-deoxy-D-glucose ({sup 18}F-FDG) positron emission tomography (PET) has been investigated in thymic epithelial tumors. However, little is known about PET imaging of {sup 18}F-FDG in primary non-thymic mediastinal neoplasms. The aim of this study is to explore the clinicopathological significance of {sup 18}F-FDG PET in primary mediastinal (non-thymic) neoplasms. Methods: Twenty-one patients with mediastinal neoplasms who underwent {sup 18}F-FDG PET before treatment were included in this study. Tumor sections were stained by immunohistochemistry for glucose transporter 1 (Glut1); glucose transporter 3 (Glut3); hypoxia-inducible factor-1 alpha (HIF-1α); hexokinase I; vascular endothelial growth factor (VEGF); microvessels (CD34); epidermal growth factor receptor (EGFR); Akt/mTOR signaling pathway (p-Akt and p-mTOR); cell cycle control (p53). Results: Seventeen of 21 patients were imaged on PET system using {sup 18}F-FDG, but 4 patients with a histology of cyst showed nothing abnormal in PET scans. The histology of the resected tumors was as follows: 6 schwannoma, 3 teratoma, 4 cyst, 3 sarcoma, 1 undifferentiated carcinoma, 1 seminoma, 1 mediastinal goiter, 1 ganglioneuroma, and 1 Hodgkin lymphoma. {sup 18}F-FDG uptake was significantly correlated with Glut1, HIF-1α, EGFR, p-Akt and p-S6K. These biomarkers were highly expressed in schwannoma, teratoma and high grade malignancies, whereas all patients with cyst and ganglioneuroma had no positive expression of these biomarkers. High uptake of {sup 18}F-FDG was significant associated with Glut1, VEGF, EGFR, p-Akt, p-S6K and tumor maximal size. Conclusion: The amount of {sup 18}F-FDG uptake in primary mediastinal non-thymic neoplasms is determined by the presence of glucose metabolism (Glut1), hypoxia (HIF-1α) and upstream components of HIF-1α (EGFR, p-Akt and p-S6K)

  9. Factors Affecting the Uptake of HIV Testing among Men: A Mixed-Methods Study in Rural Burkina Faso.

    Directory of Open Access Journals (Sweden)

    Manuela De Allegri

    Full Text Available This study aimed to explore factors shaping the decision to undergo Human Immunodeficiency Virus (HIV testing among men in rural Burkina Faso.The study took place in 2009 in the Nouna Health District and adopted a triangulation mixed methods design. The quantitative component relied on data collected through a structured survey on a representative sample of 1130 households. The qualitative component relied on 38 in-depth interviews, with men purposely selected to represent variation in testing decision, age, and place of residence. A two-part model was conducted, with two distinct outcome variables, i.e. "being offered an HIV test" and "having done an HIV test". The qualitative data analysis relied on inductive coding conducted by three independent analysts.Of the 937 men, 357 had been offered an HIV test and 97 had taken the test. Younger age, household wealth, living in a village under demographic surveillance, and knowing that HIV testing is available at primary health facilities were all positively associated with the probability of being offered an HIV test. Household wealth and literacy were found to be positively associated, and distance was found to be negatively associated with the probability of having taken an HIV test. Qualitative findings indicated that the limited uptake of HIV testing was linked to poor knowledge on service availability and to low risk perceptions.With only 10% of the total sample ever having tested for HIV, our study confirmed that male HIV testing remains unacceptably low in Sub-Saharan Africa. This results from a combination of health system factors, indicating general barriers to access, and motivational factors, such as one's own knowledge of service availability and risk perceptions. Our findings suggested that using antenatal care and curative services as the exclusive entry points into HIV testing may not be sufficient to reach large portions of the male population. Thus, additional strategies are urgently

  10. Use of gamma probe in {sup 131}I thyroid uptake studies; Utilizacao da sonda a cintilacao na captacao de {sup 131}I pela tireoide

    Energy Technology Data Exchange (ETDEWEB)

    Sarmento, Andrea Gondim Leitao

    2002-11-01

    Evaluation of thyroid uptake by administration of radioactive iodine is a well-defined procedure to assess patient thyroid function. In general, nuclear medicine institutions use gamma cameras coupled to pinhole collimators to perform uptake studies. With the growing use of intraoperative gamma probes in the radioguided surgical techniques, several institutions are purchasing this new and portable equipment, which can technically be also employed to assess patient's thyroid function, permitting further other applications of gamma cameras. The aim of the study was to compare thyroid uptake trails carried out with both gamma camera and intraoperative gamma probe, in order to evaluate the possible use of gamma probe for this purpose. At first a preliminary study of feasibility was carried out using a neck phantom to verify equipment efficiency with known activities of {sup 131} I. Henceforth, work data from 12 patients undergone studies of thyroid uptakes were evaluated, 24 hours after oral administration of 370 kBq of {sup 131} I. The maximum difference observed between the values obtained with both equipment was 60%, which demonstrated the feasibility of the proposed protocol and made clear that gamma probe can be useful for thyroid uptake studies. (author)

  11. Uptake of silica covered Quantum Dots into living cells: Long term vitality and morphology study on hyaluronic acid biomaterials.

    Science.gov (United States)

    D'Amico, Michele; Fiorica, Calogero; Palumbo, Fabio Salvatore; Militello, Valeria; Leone, Maurizio; Dubertret, Benoit; Pitarresi, Giovanna; Giammona, Gaetano

    2016-10-01

    Quantum Dots (QDs) are promising very bright and stable fluorescent probes for optical studies in the biological field but water solubility and possible metal bio-contamination need to be addressed. In this work, a simple silica-QD hybrid system is prepared and the uptake in bovine chondrocytes living cells without any functionalization of the external protective silica shield is demonstrated. Moreover, long term treated cells vitality (up to 14days) and the transfer of silica-QDs to the next cell generations are here reported. Confocal fluorescence microscopy was also used to determine the morphology of the so labelled cells and the relative silica-QDs distribution. Finally, we employ silica-QD stained chondrocytes to characterize, as proof of concept, hydrogels obtained from an amphiphilic derivative of hyaluronic acid (HA-EDA-C18) functionalized with different amounts of the RGD peptide.

  12. Prevalence and predictors of periconceptional folic acid uptake--prospective cohort study in an Irish urban obstetric population.

    LENUS (Irish Health Repository)

    McGuire, M

    2012-02-01

    BACKGROUND: Neural tube defects (NTDs) are severe abnormalities of the central nervous system that occur as a result of abnormal development in the third and fourth weeks of gestation. Studies have shown that periconceptional folic acid (FA) can reduce both the incidence and recurrence of NTDs. METHODS: A cohort study was carried out using the electronic hospital booking records of women delivering in a large Dublin maternity hospital between 2000 and 2007. Logistic regression analyses were performed to measure the associations between maternal factors and optimal FA use. RESULTS: Of the 61,252 women in the cohort, 85% reported taking FA at some point during the periconceptional period; however, only 28% took FA as recommended. Factors associated with taking the recommended amount of FA included nulliparity [adjusted OR: 1.35 (95% CI: 1.28-1.43)], early booking (<12 weeks) [OR: 1.24 (95% CI: 1.17-1.31)], increasing maternal age (e.g. 30-34 years) [OR: 1.39 (95% CI: 1.30-1.48)], private health care [OR: 4.32 (95% CI: 4.1-4.6)] and fertility treatment [OR: 2.88 (95% CI: 2.44-3.40)]. Factors associated with taking less than recommended or no FA included unplanned pregnancy [OR: 0.08 (0.07-0.08)], lower socio-economic status (e.g. unemployed) [OR: 0.63 (95% CI: 0.55-0.71)], non-Irish nationality [OR: 0.82 (0.74-0.90)] and smokers [OR: 0.51 (95% CI: 0.47-0.55)]. CONCLUSIONS: Social, demographic and economic factors have an important influence on the FA uptake. Vulnerable groups who report limited uptake of FA need to be specifically targeted in future Public Health campaigns and further consideration needs to be given to the debate on food fortification in countries where this is currently not available.

  13. Mechanism of uranium(VI) uptake by Saccharomyces cerevisiae under environmentally relevant conditions: Batch, HRTEM, and FTIR studies

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xia, E-mail: lux2009@lzu.edu.cn; Zhou, Xiao-jiao; Wang, Tie-shan, E-mail: tswang@lzu.edu.cn

    2013-11-15

    Highlights: • Equilibrium reaches very rapid within 15 min. • pH shift towards neutral indicates release of hydroxyl ions. • High ionic strength inhabits biosorption capacity. • Uptake capacity of heat-killed cells is an order of magnitude higher than live one. • Electrostatic interaction, precipitation, and complexation are the main mechanisms. -- Abstract: Biosorption is of significance for the safety evaluation of high-level nuclear wastes repositories and remediation of radioactive contamination places. Quantitive study and structural characterization of uranium uptake by both live and heat-killed Saccharomyces cerevisiae at environmentally relevant uranium concentration and with different ionic strengths were carried out. Kinetic investigation showed the equilibrium reached within 15 min. In equilibrium studies, pH shift towards neutral indicated release of hydroxyl ions. pH was the most important factor, which partly affected electrostatic interaction between uranyl ions and S. cerevisiae surface. The high ionic strength inhibited biosorption capacity, which can be explained by a competitive reaction between sodium ions and uranyl ions. Heat killing process significantly enhanced biosorption capacity, showing an order of magnitude higher than that of live cells. High resolution transmission electron microscopy (HRTEM) coupled with energy dispersive X-ray (EDX) showed needle-like uranium-phosphate precipitation formed on the cell walls for both live and heat-killed cells. Besides, dark-field micrographs displayed considerable similar uranium-phosphate precipitation presented outside the heat-killed cells. The phosphate released during heat-killing process. FTIR illustrated function groups hydroxyl, carboxyl, phosphate, and amino groups played important role in complexation with uranium.

  14. Water uptake of biomass burning aerosol at sub- and supersaturated conditions: closure studies and implications for the role of organics

    Directory of Open Access Journals (Sweden)

    U. Dusek

    2010-12-01

    Full Text Available We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types, peat and grass. The water uptake at sub- and supersaturations is parameterized by deriving a soluble volume fraction (ε. It is defined as the volume fraction of ammonium sulfate in the total aerosol material, which would be sufficient to explain the observed water uptake. For the wood burns, soluble volume fractions are low, generally around 0.11. This translates to a hygroscopicity parameter κ (another widely used parameterization; cf. Petters and Kreidenweis, 2007 of around 0.07. The main emphasis of this study is a comparison of ε derived from measurements at sub- and supersaturated conditions εG and εCCN, in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in εG and εCCN can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that εG and εCCN agree within experimental uncertainties (of around 30% for particle sizes of 100 and 150 nm; only for 50 nm particles is εCCN larger than εG by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the

  15. Water uptake of biomass burning aerosol at sub- and supersaturated conditions: closure studies and implications for the role of organics

    Science.gov (United States)

    Dusek, U.; Frank, G. P.; Massling, A.; Zeromskiene, K.; Iinuma, Y.; Schmid, O.; Helas, G.; Hennig, T.; Wiedensohler, A.; Andreae, M. O.

    2010-12-01

    We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH) of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types, peat and grass. The water uptake at sub- and supersaturations is parameterized by deriving a soluble volume fraction (ɛ). It is defined as the volume fraction of ammonium sulfate in the total aerosol material, which would be sufficient to explain the observed water uptake. For the wood burns, soluble volume fractions are low, generally around 0.11. This translates to a hygroscopicity parameter κ (another widely used parameterization; cf. Petters and Kreidenweis, 2007) of around 0.07. The main emphasis of this study is a comparison of ɛ derived from measurements at sub- and supersaturated conditions ɛG and ɛCCN), in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in ɛG and ɛCCN can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that ɛG and ɛCCN agree within experimental uncertainties (of around 30%) for particle sizes of 100 and 150 nm; only for 50 nm particles is ɛCCN larger than ɛG by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the hygroscopicity of the organic fraction is roughly 1/3 that of ammonium sulfate and can be represented by κ

  16. UNderstanding uptake of Immunisations in TravellIng aNd Gypsy communities (UNITING): a qualitative interview study.

    Science.gov (United States)

    Jackson, Cath; Dyson, Lisa; Bedford, Helen; Cheater, Francine M; Condon, Louise; Crocker, Annie; Emslie, Carol; Ireland, Lana; Kemsley, Philippa; Kerr, Susan; Lewis, Helen J; Mytton, Julie; Overend, Karen; Redsell, Sarah; Richardson, Zoe; Shepherd, Christine; Smith, Lesley

    2016-01-01

    BACKGROUND Gypsies, Travellers and Roma (referred to as Travellers) are less likely to access health services, including immunisation. To improve immunisation rates, we need to understand what helps and hinders individuals in these communities in taking up immunisations. AIMS (1) Investigate the barriers to and facilitators of acceptability and uptake of immunisations among six Traveller communities across four UK cities; and (2) identify possible interventions to increase uptake of immunisations in these Traveller communities that could be tested in a subsequent feasibility study. METHODS Three-phase qualitative study underpinned by the social ecological model. Phase 1: interviews with 174 Travellers from six communities: Romanian Roma (Bristol); English Gypsy/Irish Traveller (Bristol); English Gypsy (York); Romanian/Slovakian Roma (Glasgow); Scottish Showpeople (Glasgow); and Irish Traveller (London). Focus on childhood and adult vaccines. Phase 2: interviews with 39 service providers. Data were analysed using the framework approach. Interventions were identified using a modified intervention mapping approach. Phase 3: 51 Travellers and 25 service providers attended workshops and produced a prioritised list of potentially acceptable and feasible interventions. RESULTS There were many common accounts of barriers and facilitators across communities, particularly across the English-speaking communities. Scottish Showpeople were the most similar to the general population. Roma communities experienced additional barriers of language and being in a new country. Men, women and service providers described similar barriers and facilitators. There was widespread acceptance of childhood and adult immunisation, with current parents perceived as more positive than their elders. A minority of English-speaking Travellers worried about multiple/combined childhood vaccines, adult flu and whooping cough. Cultural concerns about vaccines offered during pregnancy and about human

  17. Uptake and cytotoxicity of citrate-coated gold nanospheres: Comparative studies on human endothelial and epithelial cells

    Directory of Open Access Journals (Sweden)

    Freese Christian

    2012-07-01

    Full Text Available Abstract Background The use of gold nanoparticles (AuNPs for diagnostic applications and for drug and gene-delivery is currently under intensive investigation. For such applications, biocompatibility and the absence of cytotoxicity of AuNPs is essential. Although generally considered as highly biocompatible, previous in vitro studies have shown that cytotoxicity of AuNPs in certain human epithelial cells was observed. In particular, the degree of purification of AuNPs (presence of sodium citrate residues on the particles was shown to affect the proliferation and induce cytotoxicity in these cells. To expand these studies, we have examined if the effects are related to nanoparticle size (10, 11 nm, 25 nm, to the presence of sodium citrate on the particles' surface or they are due to a varying degree of internalization of the AuNPs. Since two cell types are present in the major barriers to the outside in the human body, we have also included endothelial cells from the vasculature and blood brain barrier. Results Transmission electron microscopy demonstrates that the internalized gold nanoparticles are located within vesicles. Increased cytotoxicity was observed after exposure to AuNPs and was found to be concentration-dependent. In addition, cell viability and the proliferation of both endothelial cells decreased after exposure to gold nanoparticles, especially at high concentrations. Moreover, in contrast to the size of the particles (10 nm, 11 nm, 25 nm, the presence of sodium citrate on the nanoparticle surface appeared to enhance these effects. The effects on microvascular endothelial cells from blood vessels were slightly enhanced compared to the effects on brain-derived endothelial cells. A quantification of AuNPs within cells by ICP-AES showed that epithelial cells internalized a higher quantity of AuNPs compared to endothelial cells and that the quantity of uptake is not correlated with the amount of sodium citrate on the

  18. Using measured soil water contents to estimate evapotranspiration and root water uptake profiles – a comparative study

    Directory of Open Access Journals (Sweden)

    M. Guderle

    2014-09-01

    Full Text Available Understanding the role of plants for soil water relations, and thus for ecosystem functioning, requires information about root water uptake. We evaluated four different complex water balance methods to estimate sink term patterns and evapotranspiration directly from soil moisture measurements. We tested four methods: the first two take the difference between two measurement intervals as evapotranspiration, thus neglecting vertical flow. The third uses regression on the soil water content time series and differences between day and night to account for vertical flow. The fourth accounts for vertical flow using a numerical model and iteratively solves for the sink term. Neither of those methods requires any a priori information of root distribution parameters or evapotranspiration, which is the advantage, compared to common root water uptake models. To test the methods, a synthetic experiment with numerical simulations for a grassland ecosystem was conducted. Additionally, the time series were perturbed to simulate common sensor errors, like those due to measurement precision and inaccurate sensor calibration. We tested each method for a range of measurement frequencies and applied performance criteria to evaluate the suitability of each method. In general, we show that methods accounting for vertical flow predict evapotranspiration and the sink term distribution more accurately than the simpler approaches. Under consideration of possible measurement uncertainties, the method based on regression and differentiating between day and night cycles leads to the best and most robust estimation of sink term patterns. It is thus an alternative to more complex inverse numerical methods. This study demonstrates that highly resolved (temporal and spatial soil water content measurements may be used to estimate the sink term profiles when the appropriate approach is used.

  19. Lipid distribution, composition and uptake in bovine articular cartilage studied using Raman micro-spectrometry and confocal microscopy.

    Science.gov (United States)

    Mansfield, Jessica Claire; Winlove, C Peter

    2017-07-01

    The distribution and composition of endogenous lipids in articular cartilage and transport of exogenous fatty acids have been investigated on a microscopic scale in fresh bovine articular cartilage. To investigate the distribution and composition of the endogenous lipids, hyperspectral Raman maps were taken of chondrocytes and their surrounding matrix in both the deep and superficial zones. These revealed differences in both lipid distribution and composition between the two zones. Extracellular lipid was observed surrounding the cells in the superficial zone but not in the deep zone. Additionally, intracellular lipid droplets were observed that were larger and more numerous in the deep zone (P = 0.01). The extracellular lipid was primarily free saturated fatty acid, whereas the cellular lipid droplets contained triglycerides with unsaturated fatty acid chains. Fatty acid uptake and transport were investigated by incubating cartilage samples in Dulbecco's modified Eagle's medium containing fluorescently labelled palmitate for a range of times and temperatures. After incubation, the palmitate distribution was imaged using confocal microscopy. Palmitate accumulated preferentially in the territorial matrix only in the superficial zone where the concentration was up to 100-fold greater than that in the bulk matrix (P = 0.001). Palmitate uptake by the chondrocytes in both zones showed differential temperature sensitivity (P = 0.05), which would support the idea that cells take up palmitate by both active and passive mechanisms. The study reveals large differences between chondrocytes in the superficial and deep zones in their lipid content, in their extracellular lipid environment and in their access to exogenous fatty acids. © 2017 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

  20. Uptake of 4-borono-2-[{sup 18}F]fluoro-L-phenylalanine in sporadic and neurofibromatosis 2-related schwannoma and meningioma studied with PET

    Energy Technology Data Exchange (ETDEWEB)

    Havu-Auren, Katja; Kiiski, Johanna; Lehtioe, Kaisa; Eskola, Olli; Oikonen, Vesa [University of Turku, Turku PET Centre, P.O. Box 52, Turku (Finland); Kulvik, Martti; Vaehaetalo, Jyrki [Helsinki University Central Hospital, Department of Neurology, Helsinki (Finland); Vuorinen, Ville [Turku University Central Hospital, Department of Neurosurgery, Turku (Finland); Jaeaeskelaeinen, Juha [Kuopio University Central Hospital, Department of Neurosurgery, Kuopio (Finland); Minn, Heikki [University of Turku, Turku PET Centre, P.O. Box 52, Turku (Finland); Turku University Central Hospital, Department of Oncology and Radiotherapy, Turku (Finland)

    2007-01-15

    Meningiomas and schwannomas associated with neurofibromatosis 2 (NF2) are difficult to control by microsurgery and stereotactic radiotherapy alone. Boron neutron capture therapy (BNCT) is a chemically targeted form of radiotherapy requiring increased concentration of boron-10 in tumour tissue. PET with the boron carrier 4-borono-2-[{sup 18}F]fluoro-L-phenylalanine ([{sup 18}F]FBPA) allows investigation of whether 4-borono-L-phenylalanine (BPA) concentrates in NF2 tumours, which would make BNCT feasible. We studied dynamic uptake of [{sup 18}F]FBPA in intracranial meningiomas (n=4) and schwannomas (n=6) of five sporadic and five NF2 patients. Tracer input function and cerebral blood volume were measured. [{sup 18}F]FBPA uptake in tumour and brain was assessed with a three-compartmental model and graphical analysis. These, together with standardised uptake values (SUVs), were used to define tumour-to-brain [{sup 18}F]FBPA tissue activity gradients. Model fits with three parameters K{sub 1} (transport), k{sub 2} (reverse transport) and k{sub 3} (intracellular metabolism) were found to best illustrate [{sup 18}F]FBPA uptake kinetics. Maximum SUV was two- to fourfold higher in tumour as compared with normal brain and independent of NF2 status. The increased uptake was due to higher transport of [{sup 18}F]FBPA in tumour. In multiple-time graphical analysis (MTGA, Gjedde-Patlak plot) the tumour-to-brain [{sup 18}F]FBPA influx constant (K{sub i} -MTGA) ratios varied between 1.8 and 5.4 in NF2-associated tumours while in sporadic tumours the ratio was 1-1.4. [{sup 18}F]FBPA PET offers a viable means to evaluate BPA uptake in meningiomas and schwannomas in NF2. Based on our results on tumour uptake of [{sup 18}F]FBPA, some of these benign neoplasms may be amenable to BNCT. (orig.)

  1. Baseline increased 18F-fluoride uptake lesions at vertebral corners on positron emission tomography predict new syndesmophyte development in ankylosing spondylitis: a 2-year longitudinal study.

    Science.gov (United States)

    Park, Eun-Kyoung; Pak, Kyoungjune; Park, Ji-Heh; Kim, Keunyoung; Kim, Seong-Jang; Kim, In-Joo; Kim, Geun-Tae; Lee, Seung-Geun

    2017-05-01

    The goal of this study was to demonstrate whether increased 18F-fluoride uptake lesions on positron emission tomography (PET) scan can predict new syndesmophyte development in patients with ankylosing spondylitis (AS). In 12 AS patients, 18F-fluoride PET and magnetic resonance imaging (MRI) was performed at baseline, and radiography was performed at baseline and the 2-year follow-up. The following data were recorded: the presence of increased 18F-fluoride uptake lesions on PET defined as an uptake greater than the uptake in the adjacent normal vertebral body; acute (type A) and advanced (type B) corner inflammatory lesions (CILs) and fat lesions on MRI; and syndesmophytes on radiography. Of 231 anterior vertebral corners without syndesmophyte at baseline, 13 type A CILs (5.5%), 2 type B CILs (0.9%), and 20 fat lesions (8.7%) on MRI and six increased fluoride uptake lesions (2.6%) on PET were observed. At the 2-year follow-up, 16 new syndesmophytes (6.9%) in eight AS patients (66.7%) occurred. New syndesmophytes developed significantly more frequently in anterior vertebral corners with increased 18F-fluoride uptake lesions (50%) or fat lesions (25%) at baseline than in those without such lesions (5.8 and 5.2%; p = 0.005 and p = 0.007, respectively). After adjusting confounding factors, baseline increased 18F-fluoride uptake lesions was independently associated with new syndesmophytes development (OR 13.8, 95% CI 1.5-124.3, p = 0.019). Fat lesions were also associated with new syndesmophytes formation. Our data suggest that 18F-fluoride PET may be applied to identify AS patients with high risk of future syndesmophyte formation.

  2. Evidence for increased cellular uptake of glutamate and aspartate in the rat hippocampus during kainic acid seizures. A microdialysis study using the "indicator diffusion' method

    DEFF Research Database (Denmark)

    Bruhn, T; Christensen, Thomas; Diemer, Nils Henrik

    1997-01-01

    Using a newly developed technique, based on microdialysis, which allows cellular uptake of glutamate and aspartate to be studied in awake animals, we investigated uptake of glutamate and aspartate in the hippocampal formation of rats during limbic seizures induced by systemical administration of ....... The results indicate that during KA-induced seizures, uptake of glutamate and aspartate is increased, possibly aimed at maintaining the extracellular homeostasis of these two excitatory amino acids.......Using a newly developed technique, based on microdialysis, which allows cellular uptake of glutamate and aspartate to be studied in awake animals, we investigated uptake of glutamate and aspartate in the hippocampal formation of rats during limbic seizures induced by systemical administration...... of kainic acid (KA). With [14C]mannitol as an extracellular reference substance, the cellular extraction of the test substance [3H]D-aspartate was measured at different stages of seizure-activity. The results were compared to those obtained in a sham operated control group. During severe generalized clonic...

  3. {sup 18}F-fluorodeoxyglucose and PET/CT for noninvasive study of exercise-induced glucose uptake in rat skeletal muscle and tendon

    Energy Technology Data Exchange (ETDEWEB)

    Skovgaard, Dorthe [University of Copenhagen, Cluster for Molecular Imaging, Faculty of Health Sciences, Copenhagen (Denmark); Bispebjerg Hospital, Institute of Sports Medicine, Copenhagen, NV (Denmark); Kjaer, Michael [Bispebjerg Hospital, Institute of Sports Medicine, Copenhagen, NV (Denmark); El-Ali, Henrik [University of Copenhagen, Cluster for Molecular Imaging, Faculty of Health Sciences, Copenhagen (Denmark); Kjaer, Andreas [University of Copenhagen, Cluster for Molecular Imaging, Faculty of Health Sciences, Copenhagen (Denmark); Rigshospitalet, Department Clinical Physiology, Nuclear Medicine and PET, Center of Diagnostic Investigations, Copenhagen (Denmark)

    2009-05-15

    To investigate exercise-related glucose uptake in rat muscle and tendon using PET/CT and to study possible explanatory changes in gene expression for the glucose transporters (GLUT1 and GLUT4). The sciatic nerve in eight Wistar rats was subjected to electrostimulation to cause unilateral isometric contractions of the calf muscle. {sup 18}F-Fluorodeoxyglucose was administered and a PET/CT scan of the hindlimbs was performed. SUVs were calculated in both Achilles tendons and the triceps surae muscles. To exclude a spill-over effect the tendons and muscles from an ex vivo group of eight rats were cut out and scanned separately (distance{>=}1 cm). Muscle contractions increased glucose uptake approximately sevenfold in muscles (p<0.001) and 36% in tendons (p<0.01). The ex vivo group confirmed the increase in glucose uptake in intact animals. GLUT1 and GLUT4 were expressed in both skeletal muscle and tendon, but no changes in mRNA levels could be detected. PET/CT can be used for studying glucose uptake in rat muscle and tendon in relation to muscle contractions; however, the increased uptake of glucose was not explained by changes in gene expression of GLUT1 and GLUT4. (orig.)

  4. Motivational and contextual determinants of HPV-vaccination uptake: A longitudinal study among mothers of girls invited for the HPV-vaccination

    NARCIS (Netherlands)

    Pot, M.; Keulen, H.M. van; Ruiter, R.A.C.; Eekhout, I.; Mollema, L.; Paulussen, T.W.G.M.

    2017-01-01

    Background In the Netherlands, HPV-vaccination uptake among 12-year-old girls remains to be lower (61% in 2016) than expected. The present study is about 1) replicating the extent to which social-psychological determinants found in earlier cross-sectional studies explain HPV-vaccination intention,

  5. Colloidal carriers of isotretinoin for topical acne treatment: skin uptake, ATR-FTIR and in vitro cytotoxicity studies.

    Science.gov (United States)

    Gürbüz, Aslı; Özhan, Gül; Güngör, Sevgi; Erdal, M Sedef

    2015-09-01

    Acne vulgaris is the chronical, multifactorial and complex disease of the pilosebaceous unit in the skin. The main goal of the topical therapy in acne is to target the drug to epidermal and deep dermal regions by minimizing systemic absorption . Isotretinoin, a retinoic acid derivative, is the most effective drug in acne pathogenesis. Because systemic treatment may cause many side effects, topical isotretinoin treatment is an option in the management of acne. However, due to its high lipophilic character, isotretinoin tends to accumulate in the upper stratum corneum, thus its penetration into the lower layers is limited, which restricts the efficiency of topical treatment. Microemulsions are fluid, isotropic, colloidal drug carriers that have been widely studied as drug delivery systems. The percutaneous transport of active agents can be enhanced by microemulsions when compared with their conventional formulations. The purpose of this study was to evaluate microemulsions as alternative topical carriers for isotretinoin with an objective to improve its skin uptake. After in vitro permeation studies, the dermal penetration of isotretinoin from microemulsions was investigated by tape stripping procedure. Confocal laser scanning microscopy provided insight about the localization of the drug in the skin. The interaction between the microemulsion components and stratum corneum lipids is studied by ATR-FTIR spectroscopy. The relative safety of the microemulsions was assessed in mouse embryonic fibroblasts using MTT viability test. The results indicate that microemulsion-based novel colloidal carriers have a potential for enhanced skin delivery and localization of isotretinoin.

  6. A dual-tracer study of extrastriatal 6-[18F]fluoro-m-tyrosine and 6-[18F]-Fluoro-L-dopa uptake in Parkinson's disease

    Science.gov (United States)

    Li, Clarence; Palotti, Matthew; Holden, James E.; Oh, Jen; Okonkwo, Ozioma; Christian, Bradley T.; Bendlin, Barbara B.; Buyan-Dent, Laura; Harding, Sandra J.; Stone, Charles K.; Dejesus, Onofre T.; Nickles, Robert J.; Gallagher, Catherine L

    2014-01-01

    6-[18F]-Fluoro-L-dopa (FDOPA) has been widely used as a biomarker for catecholamine synthesis, storage, and metabolism—its intense uptake in the striatum, and fainter uptake in other brain regions, is correlated with the symptoms and pathophysiology of Parkinson's disease (PD). 6-[18F]fluoro-m-tyrosine (FMT), which also targets L-amino acid decarboxylase, has potential advantages over FDOPA as a radiotracer because it does not form catechol-O-methyltransferase (COMT) metabolites. The purpose of the present study was to compare the regional distribution of these radiotracers in the brains of PD patients. 15 Parkinson's patients were studied with FMT and FDOPA positron emission tomography (PET) as well as high-resolution structural magnetic resonance imaging (MRI). MRI's were automatically parcellated into neuroanatomical regions of interest (ROIs) in Freesurfer (http://surfer.nmr.mgh.harvard.edu); region-specific uptake rate constants (Kocc) were generated from coregistered PET using a Patlak graphical approach. The essential findings were as follows: (1) regional Kocc were highly correlated between the radiotracers and in agreement with a previous FDOPA studies that used different ROI selection techniques; (2) FMT Kocc were higher in extrastriatal regions of relatively large uptake such as amygdala, pallidum, brainstem, hippocampus, entorhinal cortex, and thalamus, whereas cortical Kocc were similar between radiotracers; (3) while subcortical uptake of both radiotracers was related to disease duration and severity, cortical uptake was not. These results suggest that FMT may have advantages for examining pathologic changes within allocortical loop structures, which may contribute to cognitive and emotional symptoms of PD. PMID:24710997

  7. The influence of tumor oxygenation on 18F-FDG (Fluorine-18 Deoxyglucose uptake: A mouse study using positron emission tomography (PET

    Directory of Open Access Journals (Sweden)

    Green Michael V

    2006-02-01

    Full Text Available Abstract Background This study investigated whether changing a tumor's oxygenation would alter tumor metabolism, and thus uptake of 18F-FDG (fluorine-18 deoxyglucose, a marker for glucose metabolism using positron emission tomography (PET. Results Tumor-bearing mice (squamous cell carcinoma maintained at 37°C were studied while breathing either normal air or carbogen (95% O2, 5% CO2, known to significantly oxygenate tumors. Tumor activity was measured within an automatically determined volume of interest (VOI. Activity was corrected for the arterial input function as estimated from image and blood-derived data. Tumor FDG uptake was initially evaluated for tumor-bearing animals breathing only air (2 animals or only carbogen (2 animals. Subsequently, 5 animals were studied using two sequential 18F-FDG injections administered to the same tumor-bearing mouse, 60 min apart; the first injection on one gas (air or carbogen and the second on the other gas. When examining the entire tumor VOI, there was no significant difference of 18F-FDG uptake between mice breathing either air or carbogen (i.e. air/carbogen ratio near unity. However, when only the highest 18F-FDG uptake regions of the tumor were considered (small VOIs, there was a modest (21%, but significant increase in the air/carbogen ratio suggesting that in these potentially most hypoxic regions of the tumor, 18F-FDG uptake and hence glucose metabolism, may be reduced by increasing tumor oxygenation. Conclusion Tumor 18F-FDG uptake may be reduced by increases in tumor oxygenation and thus may provide a means to further enhance 18F-FDG functional imaging.

  8. Overcoming the Barriers to Uptake: A Study of 6 Danish Health-Based Serious Games Projects

    Science.gov (United States)

    Brown, Damian

    2013-01-01

    Serious gaming for health benefits is moving out of the realm of being potentially interesting, and the authors are starting to see a growing maturity in the field. This study of six serious gaming projects based either wholly or partly in Denmark investigates the changes taking place in the healthcare area based on experiences with serious gaming…

  9. Skeletal muscle blood flow and oxygen uptake at rest and during exercise in humans: a PET study with nitric oxide and cyclooxygenase inhibition

    DEFF Research Database (Denmark)

    Heinonen, Ilkka; Saltin, Bengt; Kemppainen, Jukka

    2011-01-01

    The aim of the present study was to determine the effect of nitric oxide and prostanoids on microcirculation and oxygen uptake specifically in the active skeletal muscle by use of positron emission tomography (PET). Healthy males performed 3 five min bouts of light knee-extensor exercise. Skeletal...... muscle blood flow and oxygen uptake were measured at rest and during the exercise using PET with H(2)O(15) and (15)O(2) during: 1) control conditions; 2) nitric oxide synthase (NOS) inhibition by arterial infusion of L-NMMA and 3) combined NOS and cyclooxygenase (COX) inhibition by arterial infusion of L...

  10. Heavy Metal Uptake, Translocation, and Bioaccumulation Studies of Triticum aestivum Cultivated in Contaminated Dredged Materials

    Directory of Open Access Journals (Sweden)

    Gregorio Begonia

    2005-08-01

    Full Text Available Phytoremediation is a technology that uses vegetation to remediate contaminants from water, soil, and sediments. Unlike traditional remediation techniques such as soil washing or vitrification, phytoremediation offers a technology that is solar-driven, aesthetically pleasing, and cost effective. Recent studies indicate that winter wheat (Triticum aestivum L. is a potential accumulator for heavy metals such as lead (Pb and cadmium (Cd in hydroponic systems. Based on these findings, a laboratory study was conducted with the primary objective of determining the phytoaccumulation capability of this plant species for heavy metals from contaminated dredged materials (DMs originating from two confined disposal facilities (CDF. The United States Army Corps of Engineers (USACE manages several hundred million cubic meters of DMs each year, and 5 to 10 % of these DMs require special handling because they are contaminated with hazardous substances that can move from the substrates into food webs causing unacceptable risk outside CDFs. Phytoremediation may offer an alternative to decrease this risk. Chemical analyses by USACE personnel identified 17 metals in various DMs, but in this present study, only zinc (Zn and Cd were investigated. Pre-germinated seeds of the test plants were planted under laboratory conditions in pots containing the various DMs and reference soil. Four weeks after planting, plants were harvested and separated into roots and shoots for biomass production and tissue metal concentrations analyses. Results showed that T. aestivum plants have the capacity to tolerate and grow in multiple-metal contaminated DMs with the potential of accumulating various amounts of Zn and Cd. Root and shoot biomass of T. aestivum were not significantly affected by the DMs on which the plants were grown suggesting that this plant species can grow just as well on DMs contaminated by various metals as in the reference soil. No significant differences in the Zn

  11. Heavy Metal Uptake, Translocation, and Bioaccumulation Studies of Triticum aestivum Cultivated in Contaminated Dredged Materials

    Science.gov (United States)

    Shumaker, Ketia L.; Begonia, Gregorio

    2005-01-01

    Phytoremediation is a technology that uses vegetation to remediate contaminants from water, soil, and sediments. Unlike traditional remediation techniques such as soil washing or vitrification, phytoremediation offers a technology that is solar-driven, aesthetically pleasing, and cost effective. Recent studies indicate that winter wheat (Triticum aestivum L.) is a potential accumulator for heavy metals such as lead (Pb) and cadmium (Cd) in hydroponic systems. Based on these findings, a laboratory study was conducted with the primary objective of determining the phytoaccumulation capability of this plant species for heavy metals from contaminated dredged materials (DMs) originating from two confined disposal facilities (CDF). The United States Army Corps of Engineers (USACE) manages several hundred million cubic meters of DMs each year, and 5 to 10 % of these DMs require special handling because they are contaminated with hazardous substances that can move from the substrates into food webs causing unacceptable risk outside CDFs. Phytoremediation may offer an alternative to decrease this risk. Chemical analyses by USACE personnel identified 17 metals in various DMs, but in this present study, only zinc (Zn) and Cd were investigated. Pre-germinated seeds of the test plants were planted under laboratory conditions in pots containing the various DMs and reference soil. Four weeks after planting, plants were harvested and separated into roots and shoots for biomass production and tissue metal concentrations analyses. Results showed that T. aestivum plants have the capacity to tolerate and grow in multiple-metal contaminated DMs with the potential of accumulating various amounts of Zn and Cd. Root and shoot biomass of T. aestivum were not significantly affected by the DMs on which the plants were grown suggesting that this plant species can grow just as well on DMs contaminated by various metals as in the reference soil. No significant differences in the Zn tissue

  12. The influence of surface charge on serum protein interaction and cellular uptake: studies with dendritic polyglycerols and dendritic polyglycerol-coated gold nanoparticles

    Science.gov (United States)

    Bewersdorff, Tony; Vonnemann, Jonathan; Kanik, Asiye; Haag, Rainer; Haase, Andrea

    2017-01-01

    Nanoparticles (NPs) have gained huge interest in the medical field, in particular for drug delivery purposes. However, binding of proteins often leads to fast NP uptake and rapid clearance, thereby hampering medical applications. Thus, it is essential to determine and control the bio–nano interface. This study investigated the serum protein interactions of dendritic polyglycerols (dPGs), which are promising drug delivery candidates by means of two dimensional gel electrophoresis (2DE) in combination with mass spectrometry. In order to investigate the influence of surface charge, sulfated (sulfated dendritic polyglycerol [dPGS]) and non-sulfated (dPGOH) surfaces were applied, which were synthesized on a gold core allowing for easier separation from unbound biomolecules through centrifugation. Furthermore, two different sizes for dPGS were included. Although size had only a minor influence, considerable differences were detected in protein affinity for dPGS versus dPGOH surfaces, with dPGOH binding much less proteins. Cellular uptake into human CD14+ monocytes was analyzed by flow cytometry, and dPGOH was taken up to a much lower extent compared to dPGS. By using a pull-down approach, possible cellular interaction partners of serum pre-incubated dPGS-Au20 NPs from the membrane fraction of THP-1 cells could be identified such as for instance the transferrin receptor or an integrin. Clathrin-mediated endocytosis was further investigated using chlorpromazine as an inhibitor, which resulted in a 50% decrease of the cellular uptake of dPGS. This study could confirm the influence of surface charge on protein interactions and cellular uptake of dPGS. Furthermore, the approach allowed for the identification of possible uptake receptors and insights into the uptake mechanism. PMID:28352171

  13. Uptake of Cervical Cancer Screening and Associated Factors among Women in Rural Uganda: A Cross Sectional Study.

    Directory of Open Access Journals (Sweden)

    Rawlance Ndejjo

    Full Text Available In developing countries, inadequate access to effective screening for cervical cancer often contributes to the high morbidity and mortality caused by the disease. The largest burden of this falls mostly on underserved populations in rural areas, where health care access is characterized by transport challenges, ill equipped health facilities, and lack of information access. This study assessed uptake of cervical cancer screening and associated factors among women in rural Uganda.This descriptive cross sectional study was carried out in Bugiri and Mayuge districts in eastern Uganda and utilised quantitative data collection methods. Data were collected using a semi-structured questionnaire on cervical cancer screening among females aged between 25 and 49 years who had spent six or more months in the area. Data were entered in Epidata 3.02 and analysed in STATA 12.0 statistical software. Univariate, bivariate and multivariate analyses were performed.Of the 900 women, only 43 (4.8% had ever been screened for cervical cancer. Among respondents who were screened, 21 (48.8% did so because they had been requested by a health worker, 17 (39.5% had certain signs and symptoms they associated with cervical cancer while 16 (37.2% did it voluntarily to know their status. Barriers to cervical cancer screening were negative individual perceptions 553 (64.5% and health facility related challenges 142 (16.6%. Other respondents said they were not aware of the screening service 416 (48.5%. The independent predictors of cervical cancer screening were: being recommended by a health worker [AOR = 87.85, p<0.001], knowing where screening services were offered [AOR = 6.24, p = 0.004], and knowing someone who had ever been screened [AOR = 9.48, p = 0.001].The prevalence of cervical cancer screening is very low in rural Uganda. Interventions to increase uptake of cervical cancer screening should be implemented so as to improve access to the service in rural areas.

  14. DNA-binding, cytotoxicity, cellular uptake, apoptosis and photocleavage studies of Ru(II) complexes.

    Science.gov (United States)

    N Deepika; C Shobha Devi; Y Praveen Kumar; K Laxma Reddy; P Venkat Reddy; D Anil Kumar; Surya S Singh; S Satyanarayana

    2016-07-01

    Two Ru(II) complexes [Ru(phen)2bppp](ClO4)2 (1) and [Ru(phen)27-Br-dppz](ClO4)2 (2) [phen=1,10 phenanthroline, 7-Br-dppz=7-fluorodipyrido[3,2-a:2',3'-c]phenazine, bppp=11-bromo-pyrido[2',3':5,6]pyrazino[2,3-f] [1,10]phenanthroline] have been synthesized and characterized by elemental analysis, ES-MS, (1)H-NMR, (13)C-NMR and IR. The in vitro cytotoxicity of the complexes examined against a panel of cancer cell lines (HeLa, Du145 and A549) by MTT method, both complexes show prominent anticancer activity against various cancer cells. Live cell imaging study and flow cytometric analysis demonstrate that both the complexes 1 and 2 could cross the cell membrane accumulating in the nucleus. Further, flow cytometry experiments showed that the cytotoxic Ru(II) complexes 1 and 2 induced apoptosis of HeLa tumor cell lines. Photo induced DNA cleavage studies have been performed and results indicate that both the complexes efficiently photo cleave pBR322 DNA. The binding properties of two complexes toward CT-DNA were investigated by various optical methods and viscosity measurements. The experimental results suggested that both Ru(II) complexes can intercalate into DNA base pairs. The complexes were docked into DNA-base pairs using the GOLD docking program.

  15. Uptake studies of environmentally hazardous {sup 51}Cr in Mung beans

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Anupam [Department of Botany, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019 (India); Nayak, Dalia [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Chakrabortty, Dipanwita [Sikkim Manipal University, A 15, Paryavaran Complex, New Delhi 110030 (India); Lahiri, Susanta [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)], E-mail: susanta.lahiri@saha.ac.in

    2008-01-15

    Attempt has been made to study the accumulation behaviour of a common plant, Mung bean (Vigna radiata) towards Cr(III) and Cr(VI) to have an insight on the migration and bio-magnification of Cr. For this purpose healthy germinated Mung bean seeds were sown in the sand in the presence of Hoagland's nutrient solution containing measured amount of K{sub 2}{sup 51}Cr{sub 2}O{sub 7} and {sup 51}Cr(NO{sub 3}){sub 3}.9H{sub 2}O. Growth rate was also studied in the presence and absence of phosphate salts in the medium. It has been found that the transfer of chromium from soil to plant is significantly low (maximum 5% for both Cr(III) and Cr(VI)). Maximum accumulation of Cr occurs in the root with respect to the total chromium accumulation by the plant. Other parts of the Mung bean plant, e.g. cotyledons, shoot and leaves, show negligible accumulation. Therefore, the chance of direct intake of Cr through food as well as through the grazing animals to human body is less. - The chance of bio-magnification of Cr(III) or Cr(VI) to human body via direct or indirect intake of Mung bean is negligible.

  16. Role of endocytosis in sonoporation-mediated membrane permeabilization and uptake of small molecules: a electron microscopy study

    Science.gov (United States)

    Zeghimi, A.; Escoffre, J. M.; Bouakaz, A.

    2015-12-01

    Sonoporation is a physical method that has been successfully used to deliver drugs into living cells both in vitro and in vivo for experimental and therapeutic purposes. Despite numerous studies on this topic, often reporting successful outcomes, very little is known about the mechanisms involved in the hypothesized membrane permeabilization processes. In this study, electron microscopy was used to investigate the ultra-structural modifications of cell membranes, induced by sonoporation. Here, we demonstrate that sonoporation in the presence of microbubbles induces the formation of a significant number of transient and permeant structures at the membrane level. These structures were transient with a half-life of 10 min and had a heterogeneous size distribution ranging from a few nanometers to 150 nm. We demonstrated that the number and the size of these structures were positively correlated with the enhanced intracellular uptake of small molecules. In addition, we showed that these structures were associated with caveolae-dependent endocytosis for two thirds of the recorded events, with the remaining one third related to non-specific routes such as membrane disruptions as well as caveolae-independent endocytosis. In conclusion, our observations provide direct evidences of the involvement of caveolae-endocytosis in cell membrane permeabilization to small molecules after sonoporation.

  17. A study of the uptake and biodistribution of nano-titanium dioxide using in vitro and in vivo models of oral intake

    NARCIS (Netherlands)

    MacNicoll, Alan; Kelly, Mick; Aksoy, Hatice; Kramer, Evelien; Bouwmeester, Hans; Chaudhry, Qasim

    2015-01-01

    Certain food additives may contain a sizeable fraction of particles in the nanoscale. However, little is known about the fate, behaviour and toxicological effects of orally-ingested nanoparticles. This study investigated the uptake and biodistribution of nano- and larger-sized titanium dioxide (TiO2

  18. Truncated VP28 as oral vaccine candidate against WSSV infection in shrimp: an uptake and processing study in the midgut of Penaeus monodon

    NARCIS (Netherlands)

    Kulkarni, V.; Rombout, J.H.W.M.; Singh, I.S.B.; Sudheer, N.S.; Vlak, J.M.; Caipang, C.M.A.; Brinchmann, M.; Kiron, V.

    2013-01-01

    Several oral vaccination studies have been undertaken to evoke a better protection against white spot syndrome virus (WSSV), a major shrimp pathogen. Formalin-inactivated virus and WSSV envelope protein VP28 were suggested as candidate vaccine components, but their uptake mechanism upon oral deliver

  19. Does a population survey provide reliable influenza vaccine uptake rates among high-risk groups? A case-study of the Netherlands.

    NARCIS (Netherlands)

    Kroneman, M.W.; Essen, G.A. van; Tacken, M.A.J.B.; Paget, W.J.; Verheij, R.

    2004-01-01

    All European countries have recommendations for influenza vaccination among the elderly and chronically ill. However, only a few countries are able to provide data on influenza uptake among these groups. The aim of our study is to investigate whether a population survey is an effective method of

  20. Does a population survey provide reliable influenza vaccine uptake rates among high-risk groups? A case-study of The Netherlands.

    NARCIS (Netherlands)

    Kroneman, M.W.; Essen, G.A.; Tacken, M.A.J.B.; Paget, W.J.; Verheij, R.

    2004-01-01

    All European countries have recommendations for influenza vaccination among the elderly and chronically ill. However, only a few countries are able to provide data on influenza uptake among these groups. The aim of our study is to investigate whether a population survey is an effective method of

  1. Does a population survey provide reliable influenza vaccine uptake rates among high-risk groups? A case-study of The Netherlands.

    NARCIS (Netherlands)

    Kroneman, M.W.; Essen, G.A.; Tacken, M.A.J.B.; Paget, W.J.; Verheij, R.

    2004-01-01

    All European countries have recommendations for influenza vaccination among the elderly and chronically ill. However, only a few countries are able to provide data on influenza uptake among these groups. The aim of our study is to investigate whether a population survey is an effective method of obt

  2. Does a population survey provide reliable influenza vaccine uptake rates among high-risk groups? A case-study of the Netherlands.

    NARCIS (Netherlands)

    Kroneman, M.W.; Essen, G.A. van; Tacken, M.A.J.B.; Paget, W.J.; Verheij, R.

    2004-01-01

    All European countries have recommendations for influenza vaccination among the elderly and chronically ill. However, only a few countries are able to provide data on influenza uptake among these groups. The aim of our study is to investigate whether a population survey is an effective method of obt

  3. THE STUDY OF CADMIUM UPTAKE BY WATER HYACINTH (EICHHORNIA CRASSIPES USING A NATURAL MODELLING APPROACH

    Directory of Open Access Journals (Sweden)

    Tamara E. Romanova

    2012-06-01

    Full Text Available The results of the investigation on the accumulation of cadmium by water hyacinth, depending on the conditions of pollutant exposure and the presence of various additives are discussed. The main specialty of this study is that all the experiments were carried out in natural conditions using the approach based on the application of the capacities called minicosms. It allowed estimating hit consequences of pollutant on ecosystem most really having made experiment in the conditions as much as possible close to the natural. In this article a very important problem of an accuracy and reliability of the results of trace elements determination in plants is also debated. As a result of carried investigations it was shown that the degree of cadmium extraction by hyacinth from contaminated natural water while maintaining the viability of the plants depends on the way of pollutant introducing into the reservoir and the maximum (about 79% value is observed in the case of it’s gradual entry.

  4. Comparative study on the uptake and bioimpact of metal nanoparticles released into environment

    Science.gov (United States)

    Andries, Maria; Pricop, Daniela; Grigoras, Marian; Lupu, Nicoleta; Sacarescu, Liviu; Creanga, Dorina; Iacomi, Felicia

    2015-12-01

    Metallic particles of very small size are ubiquitously released in the air, water and soil from various natural and artificial sources - the last ones with enhanced extent since nanotechnology development accelerated exponentially. In this study we focused on the impact of metal nanoparticles in vegetal species of agroindustrial interest namely the maize (Zea mais L.). Laboratory simulation of environmental pollution was carried out by using engineered nanoparticles of two types: iron oxides with magnetic properties and gold nanoparticles supplied in the form of dilutes stable suspensions in the culture medium of maize seedlings. Magnetic nanoparticle (MNPs) preparation was performed by applying chemical route from iron ferric and ferrous precursor salts in alkali reaction medium at relatively high temperature (over 80 °C). Gold nanoparticles (GNPs) synthesis was accomplished from auric hydrochloride acid in alkali reaction medium in similar temperature conditions. In both types of metallic nanoparticles citrate ions were used as coating shell with role of suspension stabilization. Plantlet response was assessed at the level of assimilatory pigment contents in green tissue of seedlings in early ontogenetic stages.

  5. Nevirapine uptake into the central nervous system of the Guinea pig: an in situ brain perfusion study.

    Science.gov (United States)

    Gibbs, J E; Gaffen, Z; Thomas, S A

    2006-05-01

    The presence of human immunodeficiency virus (HIV) in the central nervous system (CNS) is associated with the development of HIV-1-associated dementia (HAD), a major cause of HIV-related mortality. To eradicate HIV in the CNS, anti-HIV drugs need to reach the brain and cerebrospinal fluid (CSF) in therapeutic concentrations. This involves passage through the blood-brain and blood-CSF barriers. Using a well established guinea pig in situ brain perfusion model, this study investigated whether nevirapine [6H-dipyrido(3,2-b:2',3'-e)(1,4)diazepin-6-one,11-cyclopropyl-5,11-dihydro-4-methyl], a non-nucleoside reverse transcriptase inhibitor (NNRTI), could effectively accumulate in the CNS. [(3)H]Nevirapine was coperfused with [(14)C]mannitol (a vascular/paracellular permeability marker) through the carotid arteries for up to 30 min, and accumulation in the brain, CSF, and choroid plexus was measured. [(3)H]Nevirapine uptake into the cerebrum was greater than uptake of [(14)C]mannitol, indicating significant passage across the blood-brain barrier and accumulation into the brain (this was further confirmed with capillary depletion and high-performance liquid chromatography analyses). Likewise, [(3)H]nevirapine showed a great ability to cross the blood-CSF barrier and accumulate in the CSF, compared with [(14)C]mannitol. The CNS accumulation of [(3)H]nevirapine was unaffected by 100 muM nevirapine, suggesting that passage across the blood-brain barrier can occur by diffusion. Furthermore, coperfusion with 100 muM efavirenz [2H-3,1-benzoxazin-2-one, 6-chloro-4-(cyclopropylethynyl)-1,4-dihydro-4-(trifluoromethyl)-, (4S)-; another NNRTI] did not significantly alter CNS accumulation of [(3)H]nevirapine, indicating that the efficacy of nevirapine in the CNS would not be altered by the addition of this drug to a combination therapy. Together, these data indicate that this anti-HIV drug should be beneficial in the eradication of HIV within the CNS and the subsequent treatment of

  6. How to test maximal oxygen uptake: a study on timing and testing procedure of a supramaximal verification test.

    Science.gov (United States)

    Scharhag-Rosenberger, Friederike; Carlsohn, Anja; Cassel, Michael; Mayer, Frank; Scharhag, Jürgen

    2011-02-01

    Verification tests are becoming increasingly common for confirming maximal oxygen uptake (VO2 max) attainment. Yet, timing and testing procedures vary between working groups. The aims of this study were to investigate whether verification tests can be performed after an incremental test or should be performed on a separate day, and whether VO2 max can still be determined within the first testing session in subjects not satisfying the verification criterion. Forty subjects (age, 24 ± 4 years; VO2 max, 50 ± 7 mL·min-1·kg-1) performed a maximal incremental treadmill test and, 10 min afterwards, a verification test (VerifDay1) at 110% of maximal velocity (vmax). The verification criterion was a VerifDay1 peak oxygen uptake (VO2 peak) ≤5.5% higher than the incremental test value. Subjects not achieving the verification criterion performed another verification test at 115% vmax (VerifDay1') 10 min later, trying to confirm VerifDay1 VO2 peak as VO2 max. All other subjects exclusively repeated VerifDay1 on a separate day (VerifDay2). Of the 40 subjects, 6 did not satisfy the verification criterion. In 4 of them, attainment of VO2 max was confirmed by VerifDay1'. VO2 peak was equivalent between VerifDay1 and VerifDay2 (3722 ± 991 mL·min-1 vs. 3752 ± 995 mL·min-1, p = 0.56), whereas time to exhaustion was significantly longer in VerifDay2 (2:06 ± 0:22 min:s vs. 2:42 ± 0:38 min:s, p test VO2 peak does not seem to be affected by a preceding maximal incremental test. Incremental and verification tests can therefore be performed within the same testing session. In individuals not achieving the verification criterion, VO2 max can be determined by means of a subsequent, more intense verification test in most but not all cases.

  7. Water uptake by biomass burning aerosol at sub- and supersaturated conditions: closure studies and implications for the role of organics

    Science.gov (United States)

    Dusek, U.; Frank, G. P.; Massling, A.; Zeromskiene, K.; Iinuma, Y.; Schmid, O.; Helas, G.; Hennig, T.; Wiedensohler, A.; Andreae, M. O.

    2011-09-01

    We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH) of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007). For the wood burns, κ is low, generally around 0.06. The main emphasis of this study is a comparison of κ derived from measurements at sub- and supersaturated conditions (κG and κCCN), in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in κGand κCCN can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that κG and κCCN agree within experimental uncertainties (of around 30%) for particle sizes of 100 and 150 nm; only for 50 nm particles is κCCN larger than κG by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the hygroscopicity of the water-soluble organic carbon (WSOC) fraction can be represented by a κWSOC value of approximately 0.2. The effective hygroscopicity of a typical wood burning particle can therefore be represented by a linear mixture of an inorganic component with κ ≅ 0.6, a WSOC component with κ ≅ 0.2, and an insoluble component with κ = 0.

  8. Water uptake by biomass burning aerosol at sub- and supersaturated conditions: closure studies and implications for the role of organics

    Directory of Open Access Journals (Sweden)

    U. Dusek

    2011-09-01

    Full Text Available We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007. For the wood burns, κ is low, generally around 0.06. The main emphasis of this study is a comparison of κ derived from measurements at sub- and supersaturated conditions (κG and κCCN, in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in κGand κCCN can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that κG and κCCN agree within experimental uncertainties (of around 30% for particle sizes of 100 and 150 nm; only for 50 nm particles is κCCN larger than κG by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the hygroscopicity of the water-soluble organic carbon (WSOC fraction can be represented by a κWSOC value of approximately 0.2. The effective hygroscopicity of a typical wood burning particle can therefore be represented by a linear mixture of an inorganic component with κ ≅ 0.6, a WSOC

  9. Effect of caffeine on maximal oxygen uptake in wheelchair rugby players: A randomized, placebo-controlled, double-blind study

    Directory of Open Access Journals (Sweden)

    Iva Klimešová

    2017-03-01

    Full Text Available Background: The positive effects of caffeine supplementation on strength-power and endurance performance in healthy athletes have been demonstrated in many studies. A possible mechanism for its ergogenic effect relates to its influence on the central nervous system. Post-traumatic complications in cervical spinal cord injury affect almost all body systems including the nervous system. For this reason, we expect that caffeine will have a different effect of performance in the group of athletes with spinal cord injuries. Objective: To examine the effects of caffeine supplementation on maximal aerobic power in elite wheelchair rugby players. Methods: Seven elite male wheelchair rugby players with complete cervical-level SCI (C4-Th1 were recruited (mean age: 28 ± 5.42 years; mean body mass index: 26 ± 2.84 kg/m2. The effect of caffeine was assessed by an incremental arm ergometer test until volitional exhaustion. The maximal oxygen uptake (VO2max/kg, maximum power (W max/kg, peak heart rate (HR peak, and intensity of perceived exertion (RPE were measured. Participants performed the test twice with a two-week washout period. One hour before each exercise test subjects ingested a capsule of placebo or caffeine (3 mg per kg of body weight. The tests were applied in a double-blind, randomized, repeated-measures, and cross-over design. Wheelchair rugby players were chosen because of the expected high homogeneity of participants - in terms of the type and degree of disability, gender, and age of the players. Results: The monitored parameters were not significantly influenced by caffeine intervention as compared to placebo: VO2max/kg (p = .40, W max/kg (p = .34, HR peak (p = .50 and RPE (p = .50. Conclusions: The current findings suggest that a caffeine dose of 3 mg/kg body mass does not improve oxygen uptake and maximal power in elite wheelchair rugby players.

  10. Uptake of sulfuric acid mist by plant canopies. [Exposure chamber studies with maize and soybeans

    Energy Technology Data Exchange (ETDEWEB)

    Wedding, J.B.

    1979-01-01

    Wind tunnel studies and exposure chamber experiments were conducted in the Aerosol Science Laboratory at Colorado State University. Full scale, live plant canopies of 4 to 6 week old corn and soybeans were established in a large wind tunnel. Monodisperse aerosols (1 to 15 ..mu..m aerodynamic diameter) were injected into the tunnel and deposition velocities were determined for wind speeds of 183, 305, and 610 cm/sec. A minimum deposition velocity was seen to occur at 5 ..mu..m. Initially, 4 to 6 week old soybean plants were exposed to hydrated sulfuric acid mist droplets. Unquantified topically applied sulfuric acid mist was applied at a 1% or 10% volumetric concentration of acid to water. The 10% solution produced severe necrotic lesions and large chlorotic regions on the acropetal leaves. A heavy application of the 1% solution produced similar effects but with a reduced number of necrotic lesions. A light application had no visual effects on the plants even after 24 h.In addition, 4 to 6 week old corn and soybeans were placed in a glass exposure chamber. Droplets of pure 18M sulfuric acid mist (1.7 ..mu..m) were injected into the chamber at a rate commensurate with the deposition velocity results. Loading of 107 particles/cm2 were realized during exposure periods up to 10 h per day extending to 14 days total fumigation periods. No visible toxicity symptoms of damage resulted to the plants from these tests conducted at background humidity levels of approximately 40%. Scanning electron microscope observations of the 140 h treated plants showed no apparent damage due to the sulfuric acid mist treatment.

  11. Investigating Ceria Nanocrystals Uptake by Glioblastoma Multiforme Cells and its Related Effects: An Electron Microscopy Study

    KAUST Repository

    Aloufi, Bader

    2017-01-22

    Cerium oxide nanoparticles have been utilized widely nowadays in cancer research. It has been suggested by many studies that these nanoparticles are capable of having dual antioxidant behavior in healthy and cancer microenvironment; where in physiological condition, they act as antioxidant and do not affect the healthy cells, while in tumor-like condition; they act as an oxidase, and result in a selective killing for the cancer cells. In this experiment, the interaction of nanoceria with glioblastoma and healthy astrocyte cells was examined, and further correlated with the in vitro cytotoxic effects of various nanoceria concentrations (100 and 300 µg/ml) and exposure times (12, 24, and 48 hours). Electron microscopes were used to investigate the cellular-NPs interactions, and to examine the related cytotoxic effects in combination with trypan blue and propidium iodide viability assays. Our data suggest the following results. First, the two cell lines demonstrated capability of taken up the ceria through endocytosis pathway, where the NPs were recognized engulfed by double membrane vesicles at various regions over the cellular cytoplasm. Secondly, cerium oxide nanoparticles were found to affect the glioblastoma cells, but not so severely the corresponding healthy astrocytes at the various concentrations and incubation times, as revealed by the viability assays and the electron microscopy analysis. Thirdly, the viability of the glioblastoma cells after the treatment displayed a declined trend when increasing the ceria concentrations, but did not show such dependency with regard to the different time points. In all cases, the healthy astrocyte cells showed slight alterations in mitochondrial shape which did not influence their viability. Among the various nanoceria concentrations and exposure times, the most efficient dose of treatment was found to be with a concentration of 300 µg/ml at a time point of 24-hour, where higher reduction on the viability of

  12. Uptake of sulfuric acid mist by plant canopies. [Exposure chamber studies with maize and soybeans

    Energy Technology Data Exchange (ETDEWEB)

    Wedding, J.B.

    1979-01-01

    Wind tunnel studies and exposure chamber experiments were conducted in the Aerosol Science Laboratory at Colorado State University. Full scale, live plant canopies of 4 to 6 week old corn and soybeans were established in a large wind tunnel. Monodisperse aerosols (1 to 15 ..mu..m aerodynamic diameter) were injected into the tunnel and deposition velocities were determined for wind speeds of 183, 305, and 610 cm/sec. A minimum deposition velocity was seen to occur at 5 ..mu..m. Initially, 4 to 6 week old soybean plants were exposed to hydrated sulfuric acid mist droplets. Unquantified topically applied sulfuric acid mist was applied at a 1% or 10% volumetric concentration of acid to water. The 10% solution produced severe necrotic lesions and large chlorotic regions on the acropetal leaves. A heavy application of the 1% solution produced similar effects but with a reduced number of necrotic lesions. A light application had no visual effects on the plants even after 24 h.In addition, 4 to 6 week old corn and soybeans were placed in a glass exposure chamber. Droplets of pure 18M sulfuric acid mist (1.7 ..mu..m) were injected into the chamber at a rate commensurate with the deposition velocity results. Loading of 107 particles/cm2 were realized during exposure periods up to 10 h per day extending to 14 days total fumigation periods. No visible toxicity symptoms of damage resulted to the plants from these tests conducted at background humidity levels of approximately 40%. Scanning electron microscope observations of the 140 h treated plants showed no apparent damage due to the sulfuric acid mist treatment.

  13. Systemic Lipoplatin infusion results in preferential tumor uptake in human studies.

    Science.gov (United States)

    Boulikas, Teni; Stathopoulos, Georgios P; Volakakis, Nikolaos; Vougiouka, Maria

    2005-01-01

    Lipoplatin, a liposomal formulation of cisplatin, was developed with almost negligible nephrotoxicity, ototoxicity and neurotoxicity, as demonstrated in preclinical and Phase I human studies. A polyethylene-glycol coating of the liposome nanoparticles is supposed to result in tumor accumulation of the drug by extravasation through the altered tumor vasculature. We explored the hypothesis that intravenous infusion of Lipoplatin results in tumor targeting in four independent patient cases (one with hepatocellular adenocarcinoma, two with gastric cancer and one with colon cancer) who underwent Lipoplatin infusion followed by a prescheduled surgery approximately 20 h later. Direct measurement of the platinum levels in specimens from the excised tumors and normal tissues showed that the total platinum levels were on average 10-50 times higher in malignant tissue compared to the adjacent normal tissue specimens; most effective targeting was observed in colon cancer, with an accumulation up to 200-fold higher in colon tumors compared to normal colon tissue. Of the several surgical specimens, gastric tumors displayed the highest levels of total platinum suggesting Lipoplatin as a candidate anticancer agent for gastric tumors; gastric tumor specimens had up to 260 micrograms platinum /g tissue, that was higher than any tissue level in animals treated at much higher doses. Fat tissue displayed a high accumulation of total platinum in surgical specimens in three different patients, correlating to the lipid capsule of cisplatin in its Lipoplatin formulation. It was also inferred that normal tissue had more platinum trapped in the tissue but not reacted with macromolecules, whereas tumor tissue displayed platinum that reacted with cellular macromolecules; the data were consistent with a model where Lipoplatin damages more tumor compared to normal cells. In conclusion, Lipoplatin has the ability to preferentially concentrate in malignant tissue both of primary and metastatic

  14. Study on the uptake and deglycosylation of the masked forms of zearalenone in human intestinal Caco-2 cells.

    Science.gov (United States)

    Cirlini, Martina; Barilli, Amelia; Galaverna, Gianni; Michlmayr, Herbert; Adam, Gerhard; Berthiller, Franz; Dall'Asta, Chiara

    2016-12-01

    This study investigated for the first time the intestinal transfer of two modified forms of zearalenone (ZEN), zearalenone-14-glucoside (ZEN14Glc) and zearalenone-16-glucoside (ZEN16Glc), using polarized monolayers of Caco-2 cells. The cells were apically exposed to 40 μM of ZEN14Glc, ZEN16Glc and ZEN, separately. Results showed that, after apical administration, ZEN14Glc and ZEN16Glc can be detected in cellular extracts indicating uptake by intestinal cells. Moreover, the glucosylated forms were cleaved to release ZEN, with a different cleavage ability for the two conjugated isomers. In particular, ZEN16Glc seems to be less prone to deglycosylation compared to ZEN14Glc, probably on account of an increased steric hindrance. We could show that human cytosolic β-glucosidase is able to cleave ZEN14Glc liberating ZEN, but is unable to cleave ZEN16Glc.All metabolites could cross the cell membrane and be detected in the apical compartment, while ZEN was also found in the basolateral compartment together with the modified mycotoxin form. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Nanoparticle uptake and their co-localization with cell compartments - a confocal Raman microscopy study at single cell level

    Energy Technology Data Exchange (ETDEWEB)

    Estrela-Lopis, I; Donath, E [Institute of Medical Physics and Biophysics, Leipzig University, Haertelstrasse 16, 04107 Leipzig (Germany); Romero, G; Rojas, E; Moya, S E, E-mail: Irina.Estrela-Lopis@medizin.uni-leipzig.de [CIC biomaGUNE, Paseo Miramon 182 Edificio Empresarial C, 20009 San Sebastian, Gipuzkoa (Spain)

    2011-07-06

    Confocal Raman Microscopy, a non-invasive, non-destructive and label-free technique, was employed to study the uptake and localization of nanoparticles (NPs) in the Hepatocarcinoma human cell line HepG2 at the level of single cells. Cells were exposed to carbon nanotubes (CNTs) the surface of which was engineered with polyelectrolytes and lipid layers, aluminium oxide and cerium dioxide nanoparticles. Raman spectra deconvolution was applied to obtain the spatial distributions of NPs together with lipids/proteins in cells. The colocalization of the NPs with different intracellular environments, lipid bodies, protein and DNA, was inferred. Lipid coated CNTs associated preferentially with lipid rich regions, whereas polyelectrolyte coated CNTs were excluded from lipid rich regions. Al{sub 2}O{sub 3} NPs were found in the cytoplasm. CeO{sub 2} NPs were readily taken up and have been observed all over the cell. Raman z-scans proved the intracellular distribution of the respective NPs.

  16. Magnetic nanoparticles to recover cellular organelles and study the time resolved nanoparticle-cell interactome throughout uptake.

    Science.gov (United States)

    Bertoli, Filippo; Davies, Gemma-Louise; Monopoli, Marco P; Moloney, Micheal; Gun'ko, Yurii K; Salvati, Anna; Dawson, Kenneth A

    2014-08-27

    Nanoparticles in contact with cells and living organisms generate quite novel interactions at the interface between the nanoparticle surface and the surrounding biological environment. However, a detailed time resolved molecular level description of the evolving interactions as nanoparticles are internalized and trafficked within the cellular environment is still missing and will certainly be required for the emerging arena of nanoparticle-cell interactions to mature. In this paper promising methodologies to map out the time resolved nanoparticle-cell interactome for nanoparticle uptake are discussed. Thus silica coated magnetite nanoparticles are presented to cells and their magnetic properties used to isolate, in a time resolved manner, the organelles containing the nanoparticles. Characterization of the recovered fractions shows that different cell compartments are isolated at different times, in agreement with imaging results on nanoparticle intracellular location. Subsequently the internalized nanoparticles can be further isolated from the recovered organelles, allowing the study of the most tightly nanoparticle-bound biomolecules, analogous to the 'hard corona' that so far has mostly been characterized in extracellular environments. Preliminary data on the recovered nanoparticles suggest that significant portion of the original corona (derived from the serum in which particles are presented to the cells) is preserved as nanoparticles are trafficked through the cells.

  17. Oxygen uptake in water polo, comparison and agreement in cycle ergometer and eggbeater kick: A pilot study

    Directory of Open Access Journals (Sweden)

    Ligia Ignêz Engelmann

    Full Text Available Abstract The aim of this study was to compare and verify the agreement of maximal oxygen uptake (VO2 max values obtained from tests on land and in water. Twelve recreational water polo players (30.5 ± 7.7 years; 79.2 ± 7.2 kg body mass; 179.1 ± 5.9 cm height were assessed in two phases: (1 in laboratory with maximal test on a cycle ergometer and (2 in a swimming pool with maximal test in eggbeater kick. Maximum values obtained in the two tests (respectively, cycle ergometer, and eggbeater kick: VO2 max = 40.2 ± 2.7 ml.kg-1.min-1 and 38.4 ± 5.7 ml.kg-1.min-1; RER = 1.17 ± 0.08 and 1.19 ± 0.12; HR max = 181.4 ± 11.7 bpm and 179 ± 11.7 bpm; IEP = 20 and 20 did not show significant differences. According to the Bland-Altman analyses, there were acceptable limits of agreement between the two tests (land and water. Therefore, it can be concluded that the eggbeater kick test is a specific and valid protocol to asses VO2 max in water polo players.

  18. Electron microscopic studies on the uptake of exogenous marker particles by different cell types in the guinea pig metaphysis.

    Science.gov (United States)

    Thyberg, J

    1975-01-01

    Guinea pig metaphyseal bone was exposed to horse spleen ferritin in vitro and to colloidal thorium dioxide in vivo. The cellular uptake and intracellular accumulation of these marker particles were studied ultrastructurally. In vitro, the ferritin molecules were found to spread evely throughout the tissue. After 1-2 hours ferritin was mainly found in plasma membrane invaginations and in endocytic vesicles of varying size. At 4-6 hours a successive accumulation of the marker in secondary lysosomes could be observed. In addition to ferritin, the lysosomes and the large endocytic vesicles often contained other inclusions. In vivo, the pattern of intracellular accumulation of the marker particles was identical to that in vitro. Moreover, the presence within the cells of similar amounts of thorium dioxide after 1 and 4 days suggested that these indigestible molecules are stored intracellularly for a considerable time. In accordance therewith there were no definite signs of extrusion of labeled bodies or secretion of the exogenous marker by exocytosis. Ferritin and thorium dioxide were taken up by all cell types in the metaphysis. Both in vitro and in vivo perivascular cells type B ingested large amounts of marker particles, whereas chondroclasts, endothelial cells. perivascular cells type A and osteoblasts showed a more restricted endocytizing ability. On the basis of these observations, the functional significance of different cell types in the resorption of the epiphyseal cartilage and the formation of bone is discussed.

  19. Commercial probiotic bacteria and prebiotic carbohydrates: a fundamental study on prebiotics uptake, antimicrobials production and inhibition of pathogens.

    Science.gov (United States)

    Cruz-Guerrero, Alma; Hernández-Sánchez, Humberto; Rodríguez-Serrano, Gabriela; Gómez-Ruiz, Lorena; García-Garibay, Mariano; Figueroa-González, Ivonne

    2014-08-01

    Probiotics and prebiotics are among the most important functional food ingredients worldwide. The proven benefits of such ingredients to human health have encouraged the development of functional foods containing both probiotics and prebiotics. In this work, the production of antimicrobial compounds coupled to the uptake of commercial prebiotics by probiotic bacteria was investigated. The probiotic bacteria studied were able to take up commercial prebiotic carbohydrates to the same or higher extent than that observed for lactose (control carbohydrate). The growth of probiotic bacteria was coupled to the production of antimicrobials such as short-chain fatty acids (SCFA), H2 O2 and bacteriocins. A higher production of antimicrobial compounds was recorded with Oligomate 55® compared with Regulact® and Frutafit® (3-5 and 10-115 times higher SCFA and H2 O2 production, respectively). The probiotic bacteria grown with Oligomate 55® also produced bacteriocins and other non-identified antimicrobial compounds. The antimicrobials produced by the probiotic bacteria inhibited up to 50% the growth of model pathogens such as Escherichia coli, Listeria innocua and Micrococcus luteus compared with control cultures. The results here obtained are useful for the adequate selection of probiotic/prebiotics pairs and therefore in the development of efficient functional foods. © 2013 Society of Chemical Industry.

  20. Guided online treatment in routine mental health care: an observational study on uptake, drop-out and effects

    Directory of Open Access Journals (Sweden)

    Kenter Robin

    2013-01-01

    Full Text Available Abstract Background Due to limited resources patients in the Netherlands often have to wait for a minimum of six weeks after registration for mental health care to receive their first treatment session. Offering guided online treatment might be an effective solution to reduce waiting time and to increase patient outcomes at relatively low cost. In this study we report on uptake, drop-out and effects of online problem solving treatment that was implemented in a mental health center. Methods We studied all 104 consecutive patients aged 18–65 years with elevated symptoms of depression, anxiety and/or burnout who registered at the center during the first six months after implementation. They were offered a five week guided online treatment. At baseline, five weeks and twelve weeks we measured depressive (BDI-II, anxiety (HADS-A and burnout symptoms (MBI. Results A total of 55 patients (53% agreed to start with the online treatment. Patients who accepted the online treatment were more often female, younger and lower educated than those who refused. There were no baseline differences in clinical symptoms between the groups. There were large between group effect sizes after five weeks for online treatment for depression (d = 0.94 and anxiety (d = 1.07, but not for burnout (d = −.07. At twelve weeks, when both groups had started regular face-to-face treatments, we no longer found significant differences between the groups, except for anxiety (d = 0.69. Conclusion The results of this study show that the majority of patients prefer online guided online treatment instead of waiting for face-to-face treatment. Furthermore, online PST increases speed of recovery and can therefore be offered as a first step of treatment in mental healthcare.

  1. Studies on heavy metals status and their uptake by vegetables in adjoining areas of Hudiara drain in Lahore

    Directory of Open Access Journals (Sweden)

    S.R. Kashif

    2009-05-01

    Full Text Available Pakistan has a population of over 150 million and is one of the few countries that is almost completely dependant on a single river system for all its agricultural water demands. The Indus river and its tributaries provide water to over 16 million hectares of land, situated in the mainly arid and semi-arid zones of the country. A rapidly growing population, saline groundwater, a poorly performing irrigation distribution system and recurrent droughts have led to increased water shortages. Under these conditions, the use of untreated waste water being more nutritious for crops and free of cost is becoming a common and widespread practice. Hudiara drain originates from India and enters Pakistan near Hudiara village on Pakistan side and serves as a source of free water for growing crops especially vegetables on both side of the drain. This study was conducted to investigate the heavy metal contents in Hudiara drain water and their uptake by vegetables irrigated by the drain water in the adjoining area of this drain. This might serve as an indication of the future risks to humans and animals from the movement of these heavy metals in food chain by the consumption of vegetables produced using polluted water. The results indicated that Hudiara drain water in routine water analysis parameters is fit for irrigation but unfit in relation to heavy metals contents. Soil irrigated by this water is also having higher DTPA-extractable metals contents than canal irrigated and the vegetables under study were also having metal contents far high than Indian standards for safe consumption of vegetables. Highest metals contents were observed in spinach and lowest in bringals, others in between, indicating that these vegetables should be consumed carefully if produced using the p

  2. Benthic Oxygen Uptake in the Arctic Ocean Margins - A Case Study at the Deep-Sea Observatory HAUSGARTEN (Fram Strait.

    Directory of Open Access Journals (Sweden)

    Cecile Cathalot

    Full Text Available The past decades have seen remarkable changes in the Arctic, a hotspot for climate change. Nevertheless, impacts of such changes on the biogeochemical cycles and Arctic marine ecosystems are still largely unknown. During cruises to the deep-sea observatory HAUSGARTEN in July 2007 and 2008, we investigated the biogeochemical recycling of organic matter in Arctic margin sediments by performing shipboard measurements of oxygen profiles, bacterial activities and biogenic sediment compounds (pigment, protein, organic carbon, and phospholipid contents. Additional in situ oxygen profiles were performed at two sites. This study aims at characterizing benthic mineralization activity along local bathymetric and latitudinal transects. The spatial coverage of this study is unique since it focuses on the transition from shelf to Deep Ocean, and from close to the ice edge to more open waters. Biogeochemical recycling across the continental margin showed a classical bathymetric pattern with overall low fluxes except for the deepest station located in the Molloy Hole (5500 m, a seafloor depression acting as an organic matter depot center. A gradient in benthic mineralization rates arises along the latitudinal transect with clearly higher values at the southern stations (average diffusive oxygen uptake of 0.49 ± 0.18 mmol O2 m-2 d-1 compared to the northern sites (0.22 ± 0.09 mmol O2 m-2 d-1. The benthic mineralization activity at the HAUSGARTEN observatory thus increases southward and appears to reflect the amount of organic matter reaching the seafloor rather than its lability. Although organic matter content and potential bacterial activity clearly follow this gradient, sediment pigments and phospholipids exhibit no increase with latitude whereas satellite images of surface ocean chlorophyll a indicate local seasonal patterns of primary production. Our results suggest that predicted increases in primary production in the Arctic Ocean could induce a larger

  3. Benthic Oxygen Uptake in the Arctic Ocean Margins - A Case Study at the Deep-Sea Observatory HAUSGARTEN (Fram Strait).

    Science.gov (United States)

    Cathalot, Cecile; Rabouille, Christophe; Sauter, Eberhard; Schewe, Ingo; Soltwedel, Thomas

    2015-01-01

    The past decades have seen remarkable changes in the Arctic, a hotspot for climate change. Nevertheless, impacts of such changes on the biogeochemical cycles and Arctic marine ecosystems are still largely unknown. During cruises to the deep-sea observatory HAUSGARTEN in July 2007 and 2008, we investigated the biogeochemical recycling of organic matter in Arctic margin sediments by performing shipboard measurements of oxygen profiles, bacterial activities and biogenic sediment compounds (pigment, protein, organic carbon, and phospholipid contents). Additional in situ oxygen profiles were performed at two sites. This study aims at characterizing benthic mineralization activity along local bathymetric and latitudinal transects. The spatial coverage of this study is unique since it focuses on the transition from shelf to Deep Ocean, and from close to the ice edge to more open waters. Biogeochemical recycling across the continental margin showed a classical bathymetric pattern with overall low fluxes except for the deepest station located in the Molloy Hole (5500 m), a seafloor depression acting as an organic matter depot center. A gradient in benthic mineralization rates arises along the latitudinal transect with clearly higher values at the southern stations (average diffusive oxygen uptake of 0.49 ± 0.18 mmol O2 m-2 d-1) compared to the northern sites (0.22 ± 0.09 mmol O2 m-2 d-1). The benthic mineralization activity at the HAUSGARTEN observatory thus increases southward and appears to reflect the amount of organic matter reaching the seafloor rather than its lability. Although organic matter content and potential bacterial activity clearly follow this gradient, sediment pigments and phospholipids exhibit no increase with latitude whereas satellite images of surface ocean chlorophyll a indicate local seasonal patterns of primary production. Our results suggest that predicted increases in primary production in the Arctic Ocean could induce a larger export of more

  4. Increased uptake of social security benefits among long-term survivors of cancer in childhood, adolescence and young adulthood: a Norwegian population-based cohort study

    Science.gov (United States)

    Ghaderi, S; Engeland, A; Moster, D; Ruud, E; Syse, A; Wesenberg, F; Bjørge, T

    2013-01-01

    Background: As the number of cancer survivors increases, their health and welfare have come into focus. Thus, long-term medical consequences of cancer at a young age (<25 years), obtained from social security benefit records, were studied. Methods: Standardised incidence ratios (SIRs) of long-term medical consequences for 5-year cancer survivors, born during 1965–1985, were explored by linking population-based registries in Norway. Results: Among the 5-year cancer survivors (4031 individuals), 29.7% received social security benefits. The survivors had an overall 4.4 times (95% confidence interval (95% CI): 4.1–4.6) higher risk of social security benefit uptake than the cancer-free population. Survivors of malignancies of bone and connective tissues (SIR: 10.8; 95% CI: 9.1–12.9), CNS tumours (SIR: 7.7; 95% CI: 6.9–8.6) and malignancies of the haematopoietic system (SIR: 6.1; 95% CI: 5.3–7.0) had the highest risks of social security benefits uptake. The most notified causes of social security benefit uptake were diseases of the nervous system, and injury and poisoning. Conclusion: The uptake of social security benefits among 5-year cancer survivors increased substantially and it may represent a solid outcome measure for the burden of the most severe late effects, especially in countries with comparable social welfare systems. PMID:23481179

  5. Studies on Material Cycling in Evergreen Broad-Leaved Forest Ecosystem in Hangzhou:Ⅳ.Uptake,Storage and Return of S by Vegetation

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    The work was carried out to study the uptake,storage and return of S in the evergreen broad-leaved forest ecosystem of Hangzhou in Zhejiang Province,based on the annuam increments of plants and Scontents per unit weight plant organs as well as the measured data about the biological return and decomposition.Results showed that the vegetation layer had an annual S uptake of 55.02kg ha-1,which accounted for 15.8% of the total S storage in the vegetation layer,The S uptake was the highest in the arbor layer but the lowest in the shrub layer,the biological return of S was 50% higher than the biological uptake,indicating the relatively high cycling effciency of S.Nevertheless,S had a relatively low rate opf biological release,so that S trended to accumulate in the litter layer,S taken up by plants each year came mostly from precipitation and the reserve of soil.

  6. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Uptake? A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) ... of thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that ...

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... limitations of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan ... tissues in your body. top of page How is the procedure performed? Nuclear medicine imaging is usually ...

  8. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... Uptake? A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) ... of thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that ...

  9. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is ... code: Phone no: Thank you! Do you have a personal story about radiology? Share your patient story ...

  10. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... known as a thyroid uptake. It is a measurement of thyroid function, but does not involve imaging. ... eating can affect the accuracy of the uptake measurement. Jewelry and other metallic accessories should be left ...

  11. The correlation between uptake of methyl green and Feulgen staining intensity of cell nuclei. An image analysis study

    DEFF Research Database (Denmark)

    Lyon, H; Schulte, E; Hoyer, P E

    1989-01-01

    Paraffin sections of rat tissue fixed in either formaldehyde solution (3.6% w/v) or in Carnoy's fluid were stained using standardized Methyl Green-Pyronin procedures with the dyes used either simultaneously or in sequence. The sections were evaluated for the uptake of the two dyes by cell nuclei...... methods seem to be of less value....

  12. Breast and cervical cancer-screening uptake among females in Ardabil, northwest Iran: a community-based study

    Science.gov (United States)

    Farzaneh, Esmaeil; Heydari, Heshmatolah; Shekarchi, Ali Akbar; Kamran, Aziz

    2017-01-01

    Purpose Breast and cervical cancers are the most commonly diagnosed type of cancer and cause of cancer-related deaths in Iranian females. In contrast to previous studies, this study was carried out with a large sample size for assessment of breast self-examination (BSE)-, clinical breast examination (CBE)-, mammography-, and Pap smear-uptake rates and determination of associations among these screening behaviors with sociodemographic and cognitive variables in Azeri females. Materials and methods This was a cross-sectional, community-based study that was carried out among 1,134 females 20–60 years old during March–June 2016. Data-collection variables included sociodemographic questions, screening behaviors for breast and cervical cancer, self-efficacy, beliefs, and barriers to breast and cervical cancer screening. Collected data were analyzed by SPSS version 13 using χ2, Mann–Whitney U, and logistic regression tests. Results Among the 1,134 participants, 53.9%, 9.8%, and 28.1% had done BSE, CBE, and Pap smear tests, respectively, and among the 625 females aged >40 years, 187 (29.9%) had done the mammography test. Moreover, 416 (36.7%), 103 (16.5%), and 64 (5.6%) females had done BSE, mammography, and CBE regularly, respectively. Beliefs, barriers, income, health insurance, number of children, and age were all important factors for BSE and regular BSE and mammography. Females who had high belief scores were more likely to undertake mammography (odds ratio [OR]: 1.2, 95% confidence interval [CI]: 1.03–1.5), regular mammography (OR: 4.2, 95% CI: 1.9–9.3), regular CBE (OR: 1.25, 95% CI: 1.2–1.3), and Pap smears (OR: 1.2, 95% CI: 1.1–1.4). Also, females who had high self-efficacy scores were more likely to perform regular BSE (OR: 1.8, 95% CI: 1.4–2.5) and mammography (OR: 2.5, 95% CI: 1.4–4.6) than females with lower self-efficacy scores. Conclusion The frequency of breast and cervical cancer screening was low in our study. The findings of this study

  13. Th uptake on montmorillonite: a powder and polarized extended X-ray absorption fine structure (EXAFS) study.

    Science.gov (United States)

    Dähn, Rainer; Scheidegger, André M; Manceau, Alain; Curti, Enzo; Baeyens, Bart; Bradbury, Michael H; Chateigner, Daniel

    2002-05-01

    The uptake process of Th(IV) onto montmorillonite was studied using powder and polarized-EXAFS (P-EXAFS) spectroscopy. Sorption samples were prepared in 0.1 M NaClO(4) solutions either undersaturated (pH 2 and 3, [Th](initial): 2.7x10(-6) to 4x10(-4) M) or supersatured (pH 5, [Th](initial): 4.3x10(-5) to 4x10(-4) M) with respect to amorphous ThO(2). Th loading varied between 1-157 micromol/g at pH 3 and 14-166 micromol/g at pH 5 and equaled 41 micromol/g at pH 2. At pH 5 and high surface loading the EXAFS spectrum resembled that of amorphous Th(OH)(4), suggesting the precipitation of a Th hydrous hydroxide. At low and intermediate surface coverage two O coordination shells at approximately 2.24 and approximately 2.48 A, and one Si shell at 3.81-3.88 A, were systematically observed regardless of pH. The formation of Th nucleation products and Th-Si solution complexes and the sorption of Th on a silica precipitate were excluded from the EXAFS spectra analysis and solution chemistry. In these conditions, Th was shown to bond the montmorillonite surface by sharing double corners with Si tetrahedra. This structural interpretation is consistent with surface coverage calculations which showed that the edge sites were saturated in the two highest concentrated samples (34 and 157 micromol/g) at pH 3.

  14. {sup 18}F-FLT uptake kinetics in head and neck squamous cell carcinoma: A PET imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dan, E-mail: dan.liu@oncology.ox.ac.uk; Fenwick, John D. [Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ (United Kingdom); Chalkidou, Anastasia; Landau, David B.; Marsden, Paul K. [Division of Imaging Sciences and Biomedical Engineering, School of Medicine, King' s College London, St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH (United Kingdom)

    2014-04-15

    Purpose: To analyze the kinetics of 3{sup ′}-deoxy-3{sup ′}-[F-18]-fluorothymidine (18F-FLT) uptake by head and neck squamous cell carcinomas and involved nodes imaged using positron emission tomography (PET). Methods: Two- and three-tissue compartment models were fitted to 12 tumor time-activity-curves (TACs) obtained for 6 structures (tumors or involved nodes) imaged in ten dynamic PET studies of 1 h duration, carried out for five patients. The ability of the models to describe the data was assessed using a runs test, the Akaike information criterion (AIC) and leave-one-out cross-validation. To generate parametric maps the models were also fitted to TACs of individual voxels. Correlations between maps of different parameters were characterized using Pearson'sr coefficient; in particular the phosphorylation rate-constants k{sub 3-2tiss} and k{sub 5} of the two- and three-tissue models were studied alongside the flux parameters K{sub FLT-2tiss} and K{sub FLT} of these models, and standardized uptake values (SUV). A methodology based on expectation-maximization clustering and the Bayesian information criterion (“EM-BIC clustering”) was used to distil the information from noisy parametric images. Results: Fits of two-tissue models 2C3K and 2C4K and three-tissue models 3C5K and 3C6K comprising three, four, five, and six rate-constants, respectively, pass the runs test for 4, 8, 10, and 11 of 12 tumor TACs. The three-tissue models have lower AIC and cross-validation scores for nine of the 12 tumors. Overall the 3C6K model has the lowest AIC and cross-validation scores and its fitted parameter values are of the same orders of magnitude as literature estimates. Maps ofK{sub FLT} and K{sub FLT-2tiss} are strongly correlated (r = 0.85) and also correlate closely with SUV maps (r = 0.72 for K{sub FLT-2tiss}, 0.64 for K{sub FLT}). Phosphorylation rate-constant maps are moderately correlated with flux maps (r = 0.48 for k{sub 3-2tiss} vs K{sub FLT-2tiss} and r

  15. Glucose transporters and in vivo glucose uptake in skeletal and cardiac muscle: fasting, insulin stimulation and immunoisolation studies of GLUT1 and GLUT4.

    Science.gov (United States)

    Kraegen, E W; Sowden, J A; Halstead, M B; Clark, P W; Rodnick, K J; Chisholm, D J; James, D E

    1993-01-01

    Our aim was to study glucose transporters GLUT1 and GLUT4 in relation to in vivo glucose uptake in rat cardiac and skeletal muscle. The levels of both transporters were of a similar order of magnitude in whole muscle tissue (GLUT1/GLUT4 ratio varied from 0.1 to 0.6), suggesting that both may have an important physiological role in regulating muscle glucose metabolism. GLUT4 correlated very strongly (r2 = 0.97) with maximal insulin-stimulated glucose uptake (Rg' max., estimated using the glucose clamp plus 2-deoxy[3H]glucose bolus technique) in six skeletal muscles and heart. A distinct difference in regulation of the two transporters was evident in heart: in 5 h-fasted rats, basal glucose uptake and GLUT1 levels in heart were very high and both were reduced, by 90 and 60% respectively, by 48 h fasting. However, in heart (and in red skeletal muscle), neither GLUT4 levels nor Rg' max. were reduced by 48 h fasting. GLUT1 was shown to be specifically expressed in cardiac myocytes, because intracellular vesicles enriched in GLUT4 contained significant levels of GLUT1. In conclusion, the high association of muscle GLUT4 content with insulin responsiveness in different muscles, and the preservation of both with fasting, supports a predominant role of GLUT4 in insulin-mediated glucose uptake. GLUT1 may play an important role in mediating cardiac muscle glucose uptake in the basal metabolic state. Marked changes in GLUT1 expression with alterations in the metabolic state, such as prolonged fasting, may play an important role in cardiac glucose metabolism. Images Figure 1 Figure 2 PMID:8216230

  16. Application of a microwave-based desolvation system for multi-elemental analysis of wine by inductively coupled plasma based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Grindlay, Guillermo [Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, P.O. Box 99, 03080 Alicante (Spain)], E-mail: guillermo.grindlay@ua.es; Mora, Juan; Maestre, Salvador; Gras, Luis [Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, P.O. Box 99, 03080 Alicante (Spain)

    2008-11-23

    Elemental wine analysis is often required from a nutritional, toxicological, origin and authenticity point of view. Inductively coupled plasma based techniques are usually employed for this analysis because of their multi-elemental capabilities and good limits of detection. However, the accurate analysis of wine samples strongly depends on their matrix composition (i.e. salts, ethanol, organic acids) since they lead to both spectral and non-spectral interferences. To mitigate ethanol (up to 10% w/w) related matrix effects in inductively coupled plasma atomic emission spectrometry (ICP-AES), a microwave-based desolvation system (MWDS) can be successfully employed. This finding suggests that the MWDS could be employed for elemental wine analysis. The goal of this work is to evaluate the applicability of the MWDS for elemental wine analysis in ICP-AES and inductively coupled plasma mass spectrometry (ICP-MS). For the sake of comparison a conventional sample introduction system (i.e. pneumatic nebulizer attached to a spray chamber) was employed. Matrix effects, precision, accuracy and analysis throughput have been selected as comparison criteria. For ICP-AES measurements, wine samples can be directly analyzed without any sample treatment (i.e. sample dilution or digestion) using pure aqueous standards although internal standardization (IS) (i.e. Sc) is required. The behaviour of the MWDS operating with organic solutions in ICP-MS has been characterized for the first time. In this technique the MWDS has shown its efficiency to mitigate ethanol related matrix effects up to concentrations of 1% (w/w). Therefore, wine samples must be diluted to reduce the ethanol concentration up to this value. The results obtained have shown that the MWDS is a powerful device for the elemental analysis of wine samples in both ICP-AES and ICP-MS. In general, the MWDS has some attractive advantages for elemental wine analysis when compared to a conventional sample introduction system such

  17. Study protocol: Addressing evidence and context to facilitate transfer and uptake of consultation recording use in oncology: A knowledge translation implementation study

    Directory of Open Access Journals (Sweden)

    Ruether J Dean

    2011-03-01

    Full Text Available Abstract Background The time period from diagnosis to the end of treatment is challenging for newly diagnosed cancer patients. Patients have a substantial need for information, decision aids, and psychosocial support. Recordings of initial oncology consultations improve information recall, reduce anxiety, enhance patient satisfaction with communication, and increase patients' perceptions that the essential aspects of their disease and treatment have been addressed during the consultation. Despite the research evidence supporting the provision of consultation recordings, uptake of this intervention into oncology practice has been slow. The primary aim of this project is to conduct an implementation study to explicate the contextual factors, including use of evidence, that facilitate and impede the transfer and uptake of consultation-recording use in a sample of patients newly diagnosed with breast or prostate cancer. Methods Sixteen oncologists from cancer centres in three Canadian cities will participate in this three-phase study. The preimplementation phase will be used to identify and address those factors that are fundamental to facilitating the smooth adoption and delivery of the intervention during the implementation phase. During the implementation phase, breast and prostate cancer patients will receive a recording of their initial oncology consultation to take home. Patient interviews will be conducted in the days following the consultation to gather feedback on the benefits of the intervention. Patients will complete the Digital Recording Use Semi-Structured Interview (DRUSSI and be invited to participate in focus groups in which their experiences with the consultation recording will be explored. Oncologists will receive a summary letter detailing the benefits voiced by their patients. The postimplementation phase includes a conceptual framework development meeting and a seven-point dissemination strategy. Discussion Consultation

  18. (/sup 3/H)nitrobenzylthioinosine binding as a probe for the study of adenosine uptake sites in brain

    Energy Technology Data Exchange (ETDEWEB)

    Marangos, P.J.; Patel, J.; Clark-Rosenberg, R.; Martino, A.M.

    1982-07-01

    The binding of the potent adenosine uptake inhibitor (/sup 3/H)nitrobenzylthioinosine ((/sup 3/H)NBI) to brain membrane fractions was investigated. Reversible, saturable, specific, high-affinity binding was demonstrated in both rat and human brain. The KD in both was 0.15 nM with Bmax values of 140-200 fmol/mg protein. Linear Scatchard plots were routinely obtained, indicating a homogeneous population of binding sites in brain. The highest density of binding sites was found in the caudate and hypothalamus in both species. The binding site was heat labile and trypsin sensitive. Binding was also decreased by incubation of the membranes in 0.05% Triton X-100 and by treatment with dithiothreitol and iodoacetamide. Of the numerous salt and metal ions tested, only copper and zinc had significant effects on (/sup 3/H)NBI binding. The inhibitory potencies of copper and zinc were IC50 . 160 microM and 6 mM, respectively. Subcellular distribution studies revealed a high percentage of the (/sup 3/H)NBI binding sites on synaptosomes, indicating that these sites were present in the synaptic region. A study of the tissue distribution of the (/sup 3/H)NBI sites revealed very high densities of binding in erythrocyte, lung, and testis, with much lower binding densities in brain, kidney, liver, muscle, and heart. The binding affinity in the former group was approximately 1.5 nM, whereas that in the latter group was 0.15 nM, suggesting two types of binding sites. The pharmacologic profile of (/sup 3/H)NBI binding was consistent with its function as the adenosine transport site, distinct from the adenosine receptor, since thiopurines were very potent inhibitors of binding whereas adenosine receptor ligands, such as cyclohexyladenosine and 2-chloroadenosine, were three to four orders of magnitude less potent. (/sup 3/H)NBI binding in brain should provide a useful probe for the study of adenosine transport in the brain.

  19. Uptake of 2,4,6-Trinitrotoluene (TNT) by Vetiver grass (Vetiviera ziznoides L.) -- Preliminary results from a hydroponic study

    Science.gov (United States)

    Shakya, K. M.; Sarkar, D.; Datta, R.; Makris, K.; Pachanoor, D.

    2006-05-01

    2,4,6-Trinitrotoluene(TNT) is a potent mutagen and a Group C human carcinogen that has been widely used to produce munitions and explosives. As a result, vast areas that have been previously used as military ranges, munition burning and open detonation sites have been heavily contaminated with TNT. Conventional remedial activities in such contaminated sites commonly rely on methods such as incineration, land filling and soil composting. Phytoremediation offers a cost-effective solution, utilizing plants to phytoextract TNT from the contaminated soil. We propose the use of vetiver grass (Vetiveria zizanoides) to remove TNT from such contaminated soils. Vetiver is a fast-growing and adaptive grass, enabling its use in TNT-contaminated sites in a wide variety of soil types and climate. We also hypothesized that TNT removal by vetiver grass will be enhanced by utilizing a chaotropic agent (urea) to alter rhizosphere/root hair chemical environment. The objectives of this preliminary hydroponic study were: i) to investigate the effectiveness of vetiver grass in removing TNT from solution, and ii) to evaluate the use of a common agrochemical (urea) in enhancing TNT removal by vetiver grass. Vetiver plants were grown in a hydroponic system with five different TNT concentrations (0, 5, 10, 25, and 50 mg TNT L-1) and three urea concentrations (0, 0.01 and 0.1%). A plant density of 10 g L-1 and three replicate vessels per treatment were used. Aliquots were collected at several time intervals up to 192 hour, and were analyzed for TNT with HPLC. Results showed that vetiver was able to remove TNT from hydroponic solutions. The overall magnitude and kinetics of TNT removal by vetiver grass was enhanced in the presence of urea. TNT removal kinetics depended on TNT and urea initial concentrations, suggestive of second-order kinetic reactions. Preliminary results are encouraging, but in need for verification using more detailed studies involving TNT-contaminated soils. Ongoing

  20. The uptake and storage of caesium and strontium by spring wheat - a modelling study based on a field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gaerdenaes, Annemieke I.; Linnea Berglund, S.; Bengtsson, Stefan B.; Rosen, Klas [Dept. of Soil and Environment, Swedish University of Agricultural Sciences (SLU), P.O. Box 7001, 750 07 Uppsala (Sweden)

    2014-07-01

    The aim was to model, quantify, and analyse the dynamics of uptake (foliar and root) and grain storage of wet-deposited radionuclides by a growing crop. The dynamic trace element model, Tracey, for terrestrial ecosystems was used after extension with descriptions for contamination by wet-deposition, interception, and foliar uptake. Tracey contains two alternative root uptake descriptions, one driven by transpiration and one by growth. Radionuclide fluxes were assumed proportional to the corresponding water or carbon fluxes in the soil-plant-atmosphere system, simulated with the CoupModel. The extended Tracey was calibrated against data from the wet-deposition experiment at Ultuna, central Sweden. {sup 134}Cs and {sup 85}Sr were deposited on spring wheat at six growth stages in 2010 and 2011. The sensitivity for different radionuclide, plant, and soil properties were assessed by Monte Carlo simulations using the sensitivity toolbox Eikos. One thousand simulations were made for each of the 48 scenarios (2 radionuclides, 2 root uptake approaches, 6 deposition treatments, 2 years). The simulated dynamics of grains' storage of radionuclides were accepted if the simulated values were within the 95% confidence interval of the measured values at all available samplings of a deposition treatment. A ten percentage of all {sup 134}Cs and {sup 85}Sr simulations were accepted. Highest percentage of accepted simulations was found for the scenarios with deposition shortly before harvest, indicating that the added model descriptions of deposition and interception performed well. The model mimicked well that the grain storage of radionuclides increased exponentially the later in the growing season the deposition took place; the storage of radionuclides when deposited at full ripening was 250 times higher than the storage when deposition took place at tillering. The model results confirmed that foliar uptake i.e. direct atmosphere-plant transfer, fully dominates total plant

  1. Light-microscopic immunocytochemistry for Gentamicin and its use for studying uptake of the drug in kidney

    DEFF Research Database (Denmark)

    Fujiwara, Kunio; Shin, Masashi; Matsunaga, Hayato

    2009-01-01

    Gentamicin (GM) is a widely used antibiotic but shows renal toxicity. We produced a serum against GM (anti-GM) conjugated to bovine serum albumin with N-(gamma-maleimidobutyryloxy)succinimide. The antiserum was monospecific for GM and did not cross-react with the analog streptomycin, tobramycin...... compartments. This approach should be useful for accurately detecting the uptake and toxicity of the antibiotic in different tissues....

  2. Cross-sectional study on factors associated with influenza vaccine uptake and pertussis vaccination status among pregnant women in Germany.

    Science.gov (United States)

    Bödeker, Birte; Walter, Dietmar; Reiter, Sabine; Wichmann, Ole

    2014-07-16

    Pregnant women and their newborns are at increased risk for influenza-related complications; the latter also have an increased risk for pertussis-related complications. In Germany, seasonal influenza vaccination is recommended for pregnant women since 2010. A dose of pertussis-containing vaccine has been recommended since 2004 for women of childbearing age if they have not been vaccinated within the past 10 years. We conducted a nationwide cross-sectional survey among pregnant women in February/March 2013 to assess knowledge, attitudes, and practices related to influenza vaccination during pregnancy and to identify factors associated with their pertussis vaccination status. In total, 1025 pregnant women participated and provided information through a self-administered questionnaire. Of these, 23.2% were vaccinated against seasonal influenza during the 2012/13 season; 15.9% during their pregnancy. Major reasons for being unvaccinated (n=686 respondents) were lack of confidence in the vaccine (60.4%) and the perception that vaccination was not necessary (40.3%). Influenza vaccination during pregnancy was independently associated with having received influenza vaccine in the previous season, having received a recommendation from a physician, a high level of vaccine-related knowledge and of perceived disease severity. In contrast, knowledge of the recommendation for regular hand-washing to prevent influenza and the perception that vaccine-related side effects were likely to occur or likely to be severe were negatively associated with vaccine uptake. Receipt of a pertussis vaccine in the past 10 years was reported by 22.5% of participants. Pertussis vaccine uptake was independently associated with living in the Eastern federal states and receiving seasonal influenza vaccination annually, while a migration background was associated with a lower uptake. To enhance vaccine uptake in pregnant women and women of childbearing age, special efforts must be undertaken to improve

  3. Heterogeneous uptake and reactivity of formic acid on calcium carbonate particles: a Knudsen cell reactor, FTIR and SEM study.

    Science.gov (United States)

    Al-Hosney, Hashim A; Carlos-Cuellar, Sofia; Baltrusaitis, Jonas; Grassian, Vicki H

    2005-10-21

    The heterogeneous uptake and reactivity of formic acid (HCOOH), a common gas-phase organic acid found in the environment, on calcium carbonate (CaCO(3)) particles have been investigated using a Knudsen cell reactor, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). FTIR measurements show that the adsorption of formic acid on the surface of calcium carbonate results in the formation of calcium formate. Besides calcium formate, carbonic acid is also a reaction product under dry conditions (dry conditions and at low pressures, the initial uptake coefficient of formic acid on CaCO(3) particles is measured to be 3 +/- 1 x 10(-3) and decreases as the surface saturates with adsorbed products. The maximum surface coverage of formic acid under dry conditions is determined to be (3 +/- 1)x 10(14) molecules cm(-2). Under humidified conditions (RH >10%), adsorbed water on the surface of the carbonate particles participates in the surface reactivity of these particles, which results in the enhanced uptake kinetics and extent of reaction of this organic acid on CaCO(3) as well as opens up several new reaction pathways. These reaction pathways include: (i) the water-assisted dissociation of carbonic acid to CO(2) and H(2)O and (ii) the formation of calcium formate islands and crystallites, as evident by SEM images. The results presented here show that adsorbed water plays a potentially important role in the surface chemistry of gas-phase organic acids on calcium carbonate particles.

  4. Europium Uptake and Partitioning in Oat (Avena sativa) Roots as studied By Laser-Induced Fluorescence Spectroscopy and Confocal Microscopy Profiling Technique

    Energy Technology Data Exchange (ETDEWEB)

    Fellows, Robert J.; Wang, Zheming; Ainsworth, Calvin C.

    2003-11-15

    The uptake of Eu3+ by elongating oat plant roots was studied by fluorescence spectroscopy, fluorescence lifetime measurement, as well as laser excitation time-resolved confocal fluorescence profiling technique. The results of this work indicated that the initial uptake of Eu(III) by oat root was most evident within the apical meristem of the root just proximal to the root cap. Distribution of assimilated Eu(III) within the roots differentiation and elongation zone was non-uniform. Higher concentrations were observed within the vascular cylinder, specifically in the phloem and developing xylem parenchyma. Elevated levels of the metal were also observed in the root hairs of the mature root. The concentration of assimilated Eu3+ dropped sharply from the apical meristem to the differentiation and elongation zone and then gradually decreased as the distance from the root cap increased. Fluorescence spectroscopic characteristics of the assimilated Eu3+ suggested that the Eu3+ exists a s inner-sphere mononuclear complexes inside the root. This work has also demonstrated the effectiveness of a time-resolved Eu3+ fluorescence spectroscopy and confocal fluorescence profiling techniques for the in vivo, real-time study of metal[Eu3+] accumulation by a functioning intact plant root. This approach can prove valuable for basic and applied studies in plant nutrition and environmental uptake of actinide radionuclides.

  5. Reproducibility study of [{sup 18}F]FPP(RGD){sub 2} uptake in murine models of human tumor xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Edwin; Liu, Shuangdong; Chin, Frederick; Cheng, Zhen [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Gowrishankar, Gayatri; Yaghoubi, Shahriar [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Wedgeworth, James Patrick [Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Berndorff, Dietmar; Gekeler, Volker [Bayer Schering Pharma AG, Global Drug Discovery, Berlin (Germany); Gambhir, Sanjiv S. [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Canary Center at Stanford for Cancer Early Detection, Nuclear Medicine, Departments of Radiology and Bioengineering, Molecular Imaging Program at Stanford, Stanford, CA (United States)

    2011-04-15

    with level of tracer uptake. Mouse body weight, injected dose, and fasting state did not contribute to the variability of the scans; however, consistent scanning parameters were necessary to ensure accurate studies, in particular, noting tumor volume, as well as making uniform: the time of imaging after injection and the ROI size. Reanalysis of ROI placement displayed variability for %ID{sub mean}/g of 6.6 {+-} 3.9% and 0.28 {+-} 0.12% for %ID{sub max}/g. [ {sup 18}F ]FPP(RGD){sub 2} small animal PET mouse tumor xenograft studies are reproducible with relatively low variability. (orig.)

  6. Tumor Uptake of Hollow Gold Nanospheres after Intravenous and Intra-arterial Injection: PET/CT Study in a Rabbit VX2 Liver Cancer Model

    Science.gov (United States)

    Tian, Mei; Lu, Wei; Zhang, Rui; Xiong, Chiyi; Ensor, Joe; Nazario, Javier; Jackson, James; Shaw, Colette; Dixon, Katherine A.; Miller, Jennifer; Wright, Kenneth; Li, Chun; Gupta, Sanjay

    2014-01-01

    Purpose This study was designed to investigate the intratumoral uptake of hollow gold nanospheres (HAuNS) after hepatic intra-arterial (IA) and intravenous (IV) injection in a liver tumor model. Materials and Methods Fifteen VX2 tumor-bearing rabbits were randomized into five groups (N=3 in each group) that received either IV 64Cu-labeled PEG-HAuNS (IV-PEG-HAuNS), IA 64Cu-labeled PEG-HAuNS (IA-PEG-HAuNS), IV cyclic peptide (RGD)-conjugated 64Cu-labeled PEG-HAuNS (IV-RGD-PEG-HAuNS), IA RGD-conjugated 64Cu-labeled PEG-HAuNS (IA-RGD-PEG-HAuNS), or IA 64Cu-labeled PEG-HAuNS with lipiodol (IA-PEG-HAuNS-lipiodol). The animals underwent PET/CT 1 hour after injection, and uptake expressed as percentage of injected dose per gram of tissue (%ID/g) was measured in tumor and major organs. The animals were euthanized 24 hours after injection, and tissues were evaluated for radioactivity. Results At 1 hour after injection, animals in the IA-PEG-HAuNS-lipiodol group showed significantly higher tumor uptake (P < 0.001) and higher ratios of tumor-to-normal liver uptake (P < 0.001) than those in all other groups. The biodistribution of radioactivity 24 hours after injection showed that IA delivery of PEG-HAuNS with lipiodol resulted in the highest tumor uptake (0.33 %ID/g; P < 0.001) and tumor-to-normal liver ratio (P < 0.001) among all delivery methods. At 24 hours, the IA-RGD-PEG-HAuNS group showed higher tumor uptake than the IA-PEG-HAuNS group (0.20 %ID/g vs. 0.099 %ID/g; P < 0.001). Conclusion Adding iodized oil to IA-PEG-HAuNS maximizes nanoparticle delivery to hepatic tumors and therefore may be useful in targeted chemotherapy and photoablative therapy. PET/CT can be used to noninvasively monitor the biodistribution of radiolabeled HAuNS after IV or IA injection. PMID:23608932

  7. Effect of Uptake-one inhibitors on the uptake of norepinephrine and metaiodobenzylguanidine

    Energy Technology Data Exchange (ETDEWEB)

    Tobes, M.C.; Jaques, S. Jr.; Wieland, D.M.; Sisson, J.C.

    1985-08-01

    The mechanisms underlying the uptake of the radiopharmaceutical metaiodobenzylguanidine (MIBG) and the catecholamine norepinephrine (NE) were studied using cultured bovine adrenomedullary cells as an in vitro model system. Sodium-dependent and sodium-independent uptake systems have been identified and characterized for both MIBG and NE. The sodium-dependent uptake of Ne and MIBG was inhibited by the selective Uptake-one inhibitors, desmethylimipramine (DMI) and cocaine, whereas the sodium-independent uptake for NE and MIBG was much less sensitive to inhibition by these agents. The sodium-dependent uptake system fulfills the criteria for the neuronal Uptake-one system, and the sodium-independent uptake system fulfills the criteria for a passive diffusion mechanism. Arterial concentrations proximal to the dog adrenal were very small suggesting that the sodium-dependent (Uptake-one) system is predominant in vivo. Consistent with the in vitro observations, the in vivo uptake of MIBG and NE into dog adrenal medullae was effectively blocked by pretreatment with DMI or cocaine. Therefore, iodine-131 MIBG scintigraphy of the adrenal appears to reflect uptake by way of the Uptake-one system.

  8. How to make a beetle out of wood: multi-elemental stoichiometry of wood decay, xylophagy and fungivory.

    Directory of Open Access Journals (Sweden)

    Michał Filipiak

    Full Text Available The majority of terrestrial biomass is wood, but the elemental composition of its potential consumers, xylophages, differs hugely from that of wood. This causes a severe nutritional imbalance. We studied the stoichiometric relationships of 11 elements (C, N, P, K, Ca, Mg, Fe, Zn, Mn, Cu, Na in three species of pine-xylem-feeding insects, Stictoleptura rubra, Arhopalus rusticus (Coleoptera, Cerambycidae and Chalcophora mariana (Coleoptera, Buprestidae, to elucidate their mechanisms of tissue growth and to match their life histories to their dietary constraints. These beetles do not differ from other Coleoptera in their absolute elemental compositions, which are approximately 1000 (N, 100 (P, Cu and 50 (K, Na times higher than in dead but undecayed pine wood. This discrepancy diminishes along the wood decay gradient, but the elemental concentrations remain higher by an order of magnitude in beetles than in highly decayed wood. Numerical simulation of the life history of S. rubra shows that feeding on nutrient-poor undecayed wood would extend its development time to implausible values, whereas feeding on highly decomposed wood (heavily infected with fungi would barely balance its nutritional budget during the long development period of this species. The changes in stoichiometry indicate that the relative change in the nutrient levels in decaying wood cannot be attributed solely to carbon loss resulting from decomposer respiration: the action of fungi substantially enriches the decaying wood with nutritional elements imported from the outside of the system, making it a suitable food for wood-eating invertebrates.

  9. Geographical traceability of virgin olive oils from south-western Spain by their multi-elemental composition.

    Science.gov (United States)

    Beltrán, María; Sánchez-Astudillo, María; Aparicio, Ramón; García-González, Diego L

    2015-02-15

    The geographical traceability of virgin olive oil can be controlled by chemical species that are linked to the production area. Trace elements are among these species. The hypothesis is that the transfer of elements from the soil to the oil is subjected to minor variations and therefore this chemical information can be used for geographical traceability. In order to confirm this hypothesis, the trace elements of virgin olive oils from south-western Spain were analysed, and the same elements were determined in the corresponding olive-pomaces and soils. The differences in the concentration were studied according to cultivars and locations. Results show some coincidences in the selection of elements in soils (W, Fe, Na), olive-pomace (W, Fe, Na, Mg, Mn, Ca, Ba, Li) and olive oils (W, Fe, Mg, Mn, Ca, Ba, Li, Bi), which supports their utility in traceability. In the case of olive oils, 93% of the samples were correctly classified in their geographical origins (96% for Beas, 77% for Gibraleón, 91% for Niebla, and 100% for Sanlúcar de Guadiana).

  10. Multi-elemental concentrations in the tissues of the oceanic squid Todarodes filippovae from Tasmania and the southern Indian Ocean.

    Science.gov (United States)

    Kojadinovic, Jessica; Jackson, Christine H; Cherel, Yves; Jackson, George D; Bustamante, Paco

    2011-07-01

    This study investigates 14 elements (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn) in the tissues of the oceanic ommastrephid squid Todarodes filippovae from waters surrounding Île Amsterdam (southern Indian Ocean) and Tasmania (Australia). As for other cephalopod species, the digestive gland and branchial hearts showed the highest concentrations of many elements (Ag, Cd, Se, V and Zn, and Cr and Ni, respectively) highlighting their role in bioaccumulation and detoxification processes. With the exception of As and Hg, the muscles showed relatively low trace element concentrations. Squid size was positively correlated to Ag, As, Cd, Hg and Zn concentrations in Tasmanian squid and negatively correlated to all but Hg and Zn concentrations in Île Amsterdam squid. Furthermore, no differences in elemental concentrations were noted between sexes. There were, however, some differences between mated and non-mated females from Tasmania. Comparing elemental concentrations in squid from both islands, higher concentrations of Cd, Co, Cr, Ni, Pb and V in squid sampled in Île Amsterdam reflect different exposure conditions. When considering T. filippovae as a dietary resource for humans it should be noted that, given their Hg content, squids from Île Amsterdam are not recommended for consumption on a regular basis. Moreover, regardless of the squid's origin, digestive glands should be avoided as Cd and Hg concentrations were above the European Union authorized limits in these organs.

  11. Seasonal variations in water uptake of summer maize under different fertilization treatments: A case study using stable isotopes in Beijing, China

    Science.gov (United States)

    Ma, Y.; Song, X.; Sun, N.; Yang, L.; Zhang, B.

    2015-12-01

    Crop water use from soil horizons may be significantly affected by fertilization management practices. Based on stable water isotopes in crop stem and soil water, we investigated seasonal variations in water uptake patterns for summer maize influenced by amount of fertilization application during 2013 and 2014 in Beijing, China. The Bayesian stable isotope mixing model (MixSIAR) and direct inference method were used to determine water uptake depth and proportional soil water contribution to summer maize. The results showed that the main soil water source for summer maize was 0-20 cm at seeding (67.7%) and jointing stages (60.5%). Water at deep soil depths (50-90 cm and 90-200 cm) was tended to be extracted as crop grew, even up to 45.2% at grain filling stage. About 72.0% of crop water was sourced from soil water at 0-50 cm depth at maturity stage. However, pronounced differences of water uptake for summer maize with different nitrogen application rate were presented at depths of 0-20 and 20-50 cm during tasseling and grain filling stages, ranging from 5.4% to 68.9%. Comparing water uptake patterns in two experimental seasons, it was largely concentrated at 0-50 cm depth in 2013. This might be due to continuous rainfall before tasselling stage promoted crop root development in shallow soil depth. On the other hand, seasonal drought resulted in 27.2% more deep soil water contribution at grain filling stage in 2014 than that in 2013. These findings can provide quantitative implications for further studies on water flow and nitrate transport in agricultural filed.

  12. In-vivo and ex-vivo spectrofluorometric and imaging study of liposome uptake by the liver using a pH-sensitive probe

    Science.gov (United States)

    Soulie-Begu, Sylvie; Devoisselle, Jean-Marie; Mordon, Serge R.

    1995-04-01

    Liposomes are known to be uptaken by the liver cells after intraveinous injection. Only few techniques are available to follow this process in vivo like nuclear magnetic resonance spectroscopy or scintigraphy. Intracellular pathway and liposomes localization in the different liver cells require sacrifice of the animals, cells separation and electronic microscopy, then little is known about liposomes kinetic uptake by the acidic intracellular compartments in vivo. We propose in this study a new method to follow liposomes uptake in the liver in vivo using a fluorescent pH sensitive probe 5,6-carboxyfluorescein and two different composition of liposomes: phospholipids DSPC/Chol and DMPC in order to evaluate the influence of the formulation on the release characteristics of liposomes in the lysosomes. We have already demonstrated the ability of the fluorescence spectroscopy and imaging using a pH dependent probe to monitor pH in living tissues. As pH of lysosomes is very low, the kinetic liposomes uptake in this intracellular acidic compartment is followed by monitoring the pH of the whole liver in vivo and ex vivo. Carboxyfluorescein is used at high concentration (100 mM) in order to quench its fluorescence. Liposomes are injected to Wistar rats into the penil vein. After laparotomy, fluorescence spectra and images are recorded during two hours. Results show a clear relationship between formulation of liposomes and stability in the acidic compartments of hepatic cells. After sacrifice and flush with cold saline solution, pH of the liver ex vivo is found to be 5.0-5.5. Data show a rapid clearance of release dye and an uptake of liposomes by the liver cells and, as liposomes penetrate in the acidic compartment, dye is released from liposomes and is delivered in lysosomes leading to the decrease of the pH.

  13. The use of μCT and ESEM in the study of the osmosis-induced water uptake by Eurobitum bituminized radioactive waste.

    Science.gov (United States)

    Mariën, An; Valcke, Elie; Bleyen, Nele; Van Geet, Maarten; Wevers, Martine

    2012-10-01

    Laboratory water uptake tests are performed at the Belgian Nuclear Research Centre SCK•CEN to obtain insight into the hydromechanical behavior of Eurobitum bituminized radioactive waste under geological disposal conditions. Small nonradioactive and radioactive Eurobitum samples are hydrated in restricted swelling conditions (i.e., nearly constant volume conditions and constant stress conditions). Microfocus X-ray computer tomography (μCT) proves to be a very suitable technique to follow up the ingress of water in the samples. μCT analyses demonstrate that, under the studied hydration conditions, the water uptake by Eurobitum samples is a diffusion controlled process. A characterization of the partially leached samples with environmental scanning electron microscopy (ESEM) shows that the hydration of salt crystals and the subsequent dilution of the salt solution result in an increase in pore size that is limited to a few tens of μm in restricted swelling conditions. The μCT and ESEM analyses allow improvement in the understanding of water uptake by Eurobitum in restricted swelling conditions. In this article we discuss the μCT and ESEM analyses of nonradioactive Eurobitum samples that were hydrated for 2 to 4 years at a constant stress of 1, 22, 33, and 44 bar or in nearly constant volume conditions.

  14. Dietary uptake of omega-3 fatty acids in mouse tissue studied by time-of-flight secondary ion mass spectrometry (TOF-SIMS).

    Science.gov (United States)

    Sjövall, Peter; Rossmeisl, Martin; Hanrieder, Jörg; Kuda, Ondrej; Kopecky, Jan; Bryhn, Morten

    2015-07-01

    Dietary intake of omega-3 fatty acids is associated with considerable health benefits, including the prevention of metabolic disorders such as cardiovascular disease and type 2 diabetes. Furthermore, incorporation of the main omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), at the systemic level has been found to be more efficient when these fatty acids are supplied in the form of marine phospholipids compared to triglycerides. In this work, the uptake of omega-3 fatty acids and their incorporation in specific lipids were studied in adipose, skeletal muscle, and liver tissues of mice given high-fat diets with or without omega-3 supplements in the form of phospholipids or triglycerides using time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results demonstrate significant uptake of EPA and DHA, and the incorporation of these fatty acids in specific lipid molecules, in all three tissue types in response to the dietary omega-3 supplements. Moreover, the results indicate reduced concentrations of arachidonic acid (AA) and depletion of lipids containing AA in tissue samples from mice given supplementary omega-3, as compared to the control mice. The effect on the lipid composition, in particular the DHA uptake and AA depletion, was found to be significantly stronger when the omega-3 supplement was supplied in the form of phospholipids, as compared to triglycerides. TOF-SIMS was found to be a useful technique for screening the lipid composition and simultaneously obtaining the spatial distributions of various lipid classes on tissue surfaces.

  15. Presenilin promotes dietary copper uptake.

    Directory of Open Access Journals (Sweden)

    Adam Southon

    Full Text Available Dietary copper is essential for multicellular organisms. Copper is redox active and required as a cofactor for enzymes such as the antioxidant Superoxide Dismutase 1 (SOD1. Copper dyshomeostasis has been implicated in Alzheimer's disease. Mutations in the presenilin genes encoding PS1 and PS2 are major causes of early-onset familial Alzheimer's disease. PS1 and PS2 are required for efficient copper uptake in mammalian systems. Here we demonstrate a conserved role for presenilin in dietary copper uptake in the fly Drosophila melanogaster. Ubiquitous RNA interference-mediated knockdown of the single Drosophila presenilin (PSN gene is lethal. However, PSN knockdown in the midgut produces viable flies. These flies have reduced copper levels and are more tolerant to excess dietary copper. Expression of a copper-responsive EYFP construct was also lower in the midgut of these larvae, indicative of reduced dietary copper uptake. SOD activity was reduced by midgut PSN knockdown, and these flies were sensitive to the superoxide-inducing chemical paraquat. These data support presenilin being needed for dietary copper uptake in the gut and so impacting on SOD activity and tolerance to oxidative stress. These results are consistent with previous studies of mammalian presenilins, supporting a conserved role for these proteins in mediating copper uptake.

  16. The simultaneous biosynthesis and uptake of amino acids by Lactococcus lactis studied by C-13-labeling experiments

    DEFF Research Database (Denmark)

    Jensen, N.B.S.; Christensen, B.; Nielsen, Jette

    2002-01-01

    Uniformly C-13 labeled glucose was fed to a lactic acid bacterium growing on a defined medium supplemented with all proteinogenic amino acids except glutamate. Aspartate stemming from the protein pool and from the extracellular medium was enriched with C-13 disclosing a substantial de novo...... biosynthesis of this amino acid simultaneous to its uptake from the growth medium and a rapid exchange flux of aspartate over the cellular membrane. Phenylalanine, alanine, and threonine were also synthesized de novo in spite of their presence in the growth medium....

  17. Uptake of pre-exposure prophylaxis, sexual practices, and HIV incidence in men and transgender women who have sex with men: a cohort study.

    Science.gov (United States)

    Grant, Robert M; Anderson, Peter L; McMahan, Vanessa; Liu, Albert; Amico, K Rivet; Mehrotra, Megha; Hosek, Sybil; Mosquera, Carlos; Casapia, Martin; Montoya, Orlando; Buchbinder, Susan; Veloso, Valdilea G; Mayer, Kenneth; Chariyalertsak, Suwat; Bekker, Linda-Gail; Kallas, Esper G; Schechter, Mauro; Guanira, Juan; Bushman, Lane; Burns, David N; Rooney, James F; Glidden, David V

    2014-09-01

    The effect of HIV pre-exposure prophylaxis (PrEP) depends on uptake, adherence, and sexual practices. We aimed to assess these factors in a cohort of HIV-negative people at risk of infection. In our cohort study, men and transgender women who have sex with men previously enrolled in PrEP trials (ATN 082, iPrEx, and US Safety Study) were enrolled in a 72 week open-label extension. We measured drug concentrations in plasma and dried blood spots in seroconverters and a random sample of seronegative participants. We assessed PrEP uptake, adherence, sexual practices, and HIV incidence. Statistical methods included Poisson models, comparison of proportions, and generalised estimating equations. We enrolled 1603 HIV-negative people, of whom 1225 (76%) received PrEP. Uptake was higher among those reporting condomless receptive anal intercourse (416/519 [81%] vs 809/1084 [75%], p=0·003) and having serological evidence of herpes (612/791 [77%] vs 613/812 [75%] p=0·03). Of those receiving PrEP, HIV incidence was 1·8 infections per 100 person-years, compared with 2·6 infections per 100 person-years in those who concurrently did not choose PrEP (HR 0·51, 95% CI 0·26-1·01, adjusted for sexual behaviours), and 3·9 infections per 100 person-years in the placebo group of the previous randomised phase (HR 0·49, 95% CI 0·31-0·77). Among those receiving PrEP, HIV incidence was 4·7 infections per 100 person-years if drug was not detected in dried blood spots, 2·3 infections per 100 person-years if drug concentrations suggested use of fewer than two tablets per week, 0·6 per 100 person-years for use of two to three tablets per week, and 0·0 per 100 person-years for use of four or more tablets per week (p<0·0001). PrEP drug concentrations were higher among people of older age, with more schooling, who reported non-condom receptive anal intercourse, who had more sexual partners, and who had a history of syphilis or herpes. PrEP uptake was high when made available free of

  18. Study on the Iodine 125 Uptake of H460 Lung Cancer Cell Line by Co-transfection with the Human Sodium/Iodide Symporter and the Human Thyroperoxidase

    Directory of Open Access Journals (Sweden)

    Wei LI

    2010-06-01

    Full Text Available Background and objective Lung cancer harms people’s health or even lives severely. Especially, the therapy of non-small cell lung cancer (NSCLC has not been obviously improved for many years. The aim of this study is to transfer the human sodium/iodide symporter (hNIS and the human thyroperoxidase (hTPO genes into H460 lung cancer cell line, and to study the uptake ability of iodide after co-transfected hTPO and hNIS gene in cell lines. Methods Through cloning, recombination, packaging and amplifying, the recombinant adenosine virus (AdTPO was constructed. Then the protein expression of AdTPO was tested by Western blot. After transfected hNIS gene into human lung cancer cell line H460 through liposome, stably expressing hNIS gene cell lines (hNIS-H460 selected by G418 antibiotics was determined as hNIS-H460 group. Using AdTPO, hTPO gene was transducted into hNIS-H460, as AdTPO-hNIS-H460 group. H460 cell without hNIS gene was applied as control group (H460. Then, we investigated the 125I uptake assay of the above cells. Results We were successful in co-transfecting hNIS and hTPO gene into human lung cell lines H460, and were obtained hNIS and hTPO gene lung cancer cell lines (hNIS-H460 and AdTPO-hNIS-H460. In AdTPO-hNIS-H460, hNIS-H460 and H460, the uptake ability of 125I was (59 637.67±1 281.13, (48 622.17±2 242.28 and (1 440.17±372.86 counts•min-1. The uptake ability of 125I was 41 fold higher in AdTPO-hNIS-H460 than in blank control H460 (P<0.01, and 34 fold higher in hNIS-460 than in blank control H460 (P<0.01, and 1.2 fold higher in AdTPO-hNIS-H460 than in hNIS-H460 (P<0.01. Conclusion The uptake ability of 125I could increase by co-transfected hNIS and hTPO genes into human lung cancer cell lines H460.

  19. Reducing the Genetic Redundancy of Arabidopsis PHOSPHATE TRANSPORTER1 Transporters to Study Phosphate Uptake and Signaling1[OPEN

    Science.gov (United States)

    Ayadi, Amal; David, Pascale; Arrighi, Jean-François; Chiarenza, Serge; Thibaud, Marie-Christine; Nussaume, Laurent; Marin, Elena

    2015-01-01

    Arabidopsis (Arabidopsis thaliana) absorbs inorganic phosphate (Pi) from the soil through an active transport process mediated by the nine members of the PHOSPHATE TRANSPORTER1 (PHT1) family. These proteins share a high level of similarity (greater than 61%), with overlapping expression patterns. The resulting genetic and functional redundancy prevents the analysis of their specific roles. To overcome this difficulty, our approach combined several mutations with gene silencing to inactivate multiple members of the PHT1 family, including a cluster of genes localized on chromosome 5 (PHT1;1, PHT1;2, and PHT1;3). Physiological analyses of these lines established that these three genes, along with PHT1;4, are the main contributors to Pi uptake. Furthermore, PHT1;1 plays an important role in translocation from roots to leaves in high phosphate conditions. These genetic tools also revealed that some PHT1 transporters likely exhibit a dual affinity for phosphate, suggesting that their activity is posttranslationally controlled. These lines display significant phosphate deficiency-related phenotypes (e.g. biomass and yield) due to a massive (80%–96%) reduction in phosphate uptake activities. These defects limited the amount of internal Pi pool, inducing compensatory mechanisms triggered by the systemic Pi starvation response. Such reactions have been uncoupled from PHT1 activity, suggesting that systemic Pi sensing is most probably acting downstream of PHT1. PMID:25670816

  20. Theoretical molecular descriptors relevant to the uptake of persistent organic pollutants from soil by zucchini. A QSAR study.

    Science.gov (United States)

    Bordás, Barna; Bélai, Iván; Koomíves, Tamás

    2011-04-13

    The uptake of persistent organic pollutants (POPs) from soil by plants allows the development of phytoremediation protocols to rehabilitate contaminated areas. The use of diverse theoretical descriptors has been reported in the literature for developing quantitative structure-activity relationship (QSAR) models for predicting the bioconcentration factors (BCFs) of POPs in different plants. In this paper an evaluation is given on the molecular properties of POPs in terms of theoretical molecular descriptors that are relevant to the uptake and accumulation of these persistent pollutants from soil by two zucchini varieties. Statistically significant and predictive linear regression models have been developed for the BCF values of 20 polychlorinated dibenzo-p-dioxins/dibenzofurans and 14 polyhalogenated biphenyls in two zucchini varieties based on retrospective data. The relevant parameters have been selected from a set of 1660 DRAGON, 150 VolSurf, and 11 quantum chemical descriptors. The two most significant regression models, containing VolSurf, DRAGON GETAWAY, and quantum chemical descriptors, displayed the following statistical parameters: (eq 3) n = 27, R(2) = 0.940, q(2) = 0.922, SE = 0.155, F = 392.1; (eq 4) n = 27, R(2) = 0.921, q(2) = 0.898, SE = 0.161, F = 140.4. Predictive capabilities of the equations have been validated by using external validation sets. The QSAR models proposed might contribute to the development of viable soil remediation strategies.

  1. Permeability studies on taenid metacestodes: I. Uptake of proteins by larval stages of Taenia taeniaeformis, T. crassiceps, and Echinococcus granulosus.

    Science.gov (United States)

    Hustead, S T; Williams, J F

    1977-04-01

    Host immunoglobulins of several different classes were detected within the bladder fluids of Taenia taeniaeformis, T. crassiceps, and Echinococcus granulosus. Radioiodinated proteins were taken up in vitro by larvae of both T. taeniaeformis and T. crassiceps and were shown to retain their physicochemical and antigenic characteristics. Rates of uptake were similar in the 2 species and were not related to the molecular weight of the proteins. Immunoglobulins were taken up both in vitro and in vivo by larvae of T. taeniaeformis. Absorbed immunoglobulins were shown to retain both antigen binding capacity and biologic functions associated with the Fc portion of the molecules. Not all cysts of E. granulosus contained detectable host proteins. Uptake of 125I occurred when hydatid cysts were exposed to labeled proteins in vitro, but it appeared that rapid degradation of the labeled carrier led to the appearance of dialysable fragments. This may be attributable to proteolysis within the bladder fluid. We conclude that taeniid metacestodes are capable of absorbing a variety of proteins, and that these macromolecules can retain their structural and functional integrity following transport. This absorptive capacity accounts for the presence of host serum components within bladder fluids.

  2. Further studies on the nature of postsynaptic dopamine uptake and metabolism in rat striatum: sodium dependency and investigation of a possible role for carrier-mediated uptake into serotonin neurons

    Energy Technology Data Exchange (ETDEWEB)

    Schoepp, D.D.; Azzaro, A.J.

    1985-06-01

    The nature of postsynaptic sites involved in the uptake and metabolism of striatal 3,4-dihydroxyphenylethylamine (dopamine, DA) was investigated. The accumulation of (/sup 3/H)DA (10(-7) M) into slices of rat striatum was found to be greatly dependent on the presence of sodium ion in the incubation medium. However, the formation of the (/sup 3/H)dihydroxyphenylacetic acid (DOPAC) and (/sup 3/H)homovanillic acid (HVA) was only partially reduced in the absence of sodium. Inhibition of carrier-mediated DA neuronal uptake with nomifensine significantly decreased DA accumulation (18% of control) and (/sup 3/H)DOPAC formation (62% of control), but enhanced (/sup 3/H)HVA production (143% of control). Inhibition of the 5-hydroxytryptamine (5-HT, serotonin) neuronal uptake system with fluoxetine (10(-6) M) or selective 5-HT neuronal lesions with 5,7-dihydroxytryptamine (5,7-DHT) had no effect on (/sup 3/H)DOPAC or (/sup 3/H)HVA formed from (/sup 3/H)DA in the presence or absence of nomifensine. These results demonstrate that the uptake and subsequent metabolism of striatal DA to DOPAC and HVA is only partially dependent on carrier-mediated uptake mechanism(s) requiring sodium ion. These data support our previous findings suggesting a significant role for synaptic glial cell deamination and O-methylation of striatal DA. Further, experiments with fluoxetine or 5,7-DHT suggest that 5-HT neurons do not significantly contribute in the synaptic uptake and metabolism of striatal DA.

  3. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  4. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a thyroid uptake. ...

  5. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... of the Thyroid Scan and Uptake? What is a Thyroid Scan and Uptake? A thyroid scan is ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  6. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is also known as a thyroid uptake. ...

  7. Radioiodine uptake in inactive pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Bakheet, S.M.; Powe, J.; Al Suhaibani, H. [Department of Radiology, King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia); Hammami, M.M.; Bazarbashi, M. [Department of Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia)

    1999-06-01

    Radioiodine may accumulate at sites of inflammation or infection. We have seen such accumulation in six thyroid cancer patients with a history of previously treated pulmonary tuberculosis. We also review the causes of false-positive radioiodine uptake in lung infection/inflammation. Eight foci of radioiodine uptake were seen on six iodine-123 diagnostic scans. In three foci, the uptake was focal and indistinguishable from thyroid cancer pulmonary metastases from thyroid cancer. In the remaining foci, the uptake appeared nonsegmental, linear or lobar, suggesting a false-positive finding. The uptake was unchanged, variable in appearance or non-persistent on follow-up scans and less extensive than the fibrocystic changes seen on chest radiographs. In the two patients studied, thyroid hormone level did not affect the radioiodine lung uptake and there was congruent gallium-67 uptake. None of the patients had any evidence of thyroid cancer recurrence or of reactivation of tuberculosis and only two patients had chronic intermittent chest symptoms. Severe bronchiectasis, active tuberculosis, acute bronchitis, respiratory bronchiolitis, rheumatoid arthritis-associated lung disease and fungal infection such as Allescheria boydii and aspergillosis can lead to different patterns of radioiodine chest uptake mimicking pulmonary metastases. Pulmonary scarring secondary to tuberculosis may predispose to localized radioiodine accumulation even in the absence of clinically evident active infection. False-positive radioiodine uptake due to pulmonary infection/inflammation should be considered in thyroid cancer patients prior to the diagnosis of pulmonary metastases. (orig.) With 4 figs., 1 tab., 9 refs.

  8. Cellular uptake of modified oligonucleotides enhanced by porphyrins studied by time-resolved microspectrofluorimetry and fluorescence imaging techniques

    Science.gov (United States)

    Praus, P.; Kočišová, E.; Mojzeš, P.; Štěpánek, J.; Turpin, P.-Y.; Sureau, F.

    2011-05-01

    Fluorescence microimaging and homodyne phase-resolved confocal microspectrofluorimetry were used to monitor the transport of antisense oligonucleotide into 3T3 living cells and its subsequent intracellular distribution. Phosphorothioate analog of 15-mer oligothymidylate labeled by ATTO 425 was complexed with 5,10,15,20-tetrakis (1-methyl-4-pyridyl) porphyrin (H 2TMPyP4) as an uptake-mediating agent. High frequency (up to 180 MHz) analog modulation of both exciting diode laser and the detector image intensifier gain was used to record time-resolved fluorescence spectra. Fluorescence lifetime data within a broad spectral range have revealed preservation of oligonucleotide/porphyrin complex integrity and binding properties of both components inside the cell.

  9. Effect of EDTA on Pb(II) Uptake and Translocation by Tumbleweed (Salsola Kali): Agar and Hydroponics Studies

    Energy Technology Data Exchange (ETDEWEB)

    de la Rosa, Guadalupe; Gardea-Torresdey, Jorge L.; Peralta-Videa, Jose R.; Aldrich, Mary

    2004-03-31

    Environmental accumulation of Pb represents a worldwide health hazard. While conventional cleanup techniques are generally expensive and soil disturbing, phytoremediation represents an inexpensive friendly option for the removal of contaminants from soil and water. In this research, tumbleweed (Salsola kali) plants exposed for 15 days to Pb(NO3)2 at 80 and 125 ppm in hydroponics and agar media, demonstrated a high capacity to uptake lead. The results showed that the plants cultivated in agar accumulated 25563, 5534 and 2185 mg Pb kg-1 DW in roots, stems and leaves, respectively. Moreover, Pb concentrations found in hydroponically grown tumbleweed plants tissues were 30744, 1511 and 1421 mg kg-1 DW in roots, stems and leaves, respectively. It was observed that EDTA enhanced Pb translocation. No Pb phytotoxic effects were observed during the experimental time period. Cellular structural features were also observed using TEM.

  10. Effects of hydrostatic pressure/heat combinations on water uptake and gelatinization characteristics of japonica rice grains: a kinetic study.

    Science.gov (United States)

    Huang, Shih-Li; Jao, Chia-Ling; Hsu, Kuo-Chiang

    2009-10-01

    The combination effects of pressure (200 to 500 MPa) and temperature (20, 40, and 50 degrees C) on the water uptake and gelatinization characteristics of japonica rice (Tainung 71) grains were investigated. Pressure greater than 200 MPa at all temperatures increased the moisture content and volume of rice grains; meanwhile, the increase content of rice grain volume showed a high correlation with that of moisture content (r(2)= 0.96). The highest degree of gelatinization of 73% was observed at 500 MPa and 50 degrees C for 120 min, while gelatinization did not occur at pressures below 300 MPa and temperatures of 20 and 40 degrees C. The rate of gelatinization followed the 1st-order kinetics at each temperature and pressure. The higher pressures and temperatures would result in higher values of rate constant k which could be correlated with both pressure and temperature by combining Arrhenius and Eyring models.

  11. Pharmacokinetics of Stereoisomeric Dipeptide Prodrugs of Acyclovir Following Intravenous and Oral Administrations in Rats: A Study Involving In vivo Corneal Uptake of Acyclovir Following Oral Dosing

    Directory of Open Access Journals (Sweden)

    Ravi S.Talluri

    2009-10-01

    Full Text Available Objective: To delineate the plasma pharmacokinetics and determine the corneal uptake of valine based stereoisomeric dipeptide prodrugs of acyclovir (ACV in rats. Methods: Male Sprague-Dawley rats were used for the study. Pharmacokinetics of ACV, L-valine-acyclovir (LACV, L-valine- D-valine-acyclovir (LDACV and D-valine-L-valine acyclovir (DLACV prodrugs were delineated. These compounds were administered intravenously as a bolus via jugular vein cannula and orally by gavage. Samples were purified by protein precipitation method and analyzed by LC-MS/MS. Pertinent pharmacokinetic parameters were obtained by using WinNonlin. Corneal uptake studies of LDACV and LACV were studied following oral administration. Results: Following i.v. administration, the area under the curve (AUC in µM*min of generated ACV was in the order of LACV › LDACV › DLACV indicating their rate of metabolism. The AUC values of total drug obtained in the systemic circulation after oral administration LACV and LDACV were 1077.93 ± 236.09 and 1141.76 ± 73.67 µM*min, respectively. DLACV exhibited poor oral absorption. Cmax (µM and AUC of the intact prodrug obtained in the systemic circulation following oral administration of LDACV were almost 4–5 times higher than LACV. Moreover, concentrations achieved in the cornea after oral administration of LDACV were almost two times of LACV. Conclusions: LDACV increased both the oral bioavailability and subsequent in vivo corneal uptake of ACV. Hence, LDACV can be considered as the most promising drug candidate for delivery of ACV, in treatment of both genital herpes and ocular herpes keratitis after oral administration.

  12. Uptake of organic nitrogen by plants

    Science.gov (United States)

    Torgny Nasholm; Knut Kielland; Ulrika. Ganeteg

    2009-01-01

    Languishing for many years in the shadow of plant inorganic nitrogen (N) nutrition research, studies of organic N uptake have attracted increased attention during the last decade. The capacity of plants to acquire organic N, demonstrated in laboratory and field settings, has thereby been well established. Even so, the ecological significance of organic N uptake for...

  13. Incidental fleurodeoxyglucose uptake in the prostate.

    Science.gov (United States)

    Wong, W L; Moule, R N; Nunan, T

    2010-11-01

    This commentary confirms the rarity of prostatic cancer associated with incidental prostatic fleurodeoxyglucose (FDG) uptake. The study adds to the literature by showing that even if a prostate lesion is FDG avid it is unlikely to be due to cancer. The commentary considers the management of incidental prostate FDG uptake on the basis of the available evidence.

  14. Radio-active iodine uptake in vitiligo

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, V.; Shankar, V.; Chaudhary, S.; Bhatia, K.K.; Mehta, L.K.; Arora, D.R. (Medical College and Hospital, Rohtak-124001 (India))

    1990-01-01

    Vitiligo and thyroid disease are commonly associated disorders. Twenty-two clinically euthyroid vitiligo patients were studied for functional assessment of thyroid by radioactive iodine uptake assay. Half of them showed abnormal uptake values at 24 hours. Of these patients, 90% had lower values indicating a tendency towards developing hypothyroid state. Subclinical thyroid dysfunction in vitiligo appears to be an adaptive change. (author).

  15. A study of the uptake and biodistribution of nano-titanium dioxide using in vitro and in vivo models of oral intake

    Energy Technology Data Exchange (ETDEWEB)

    MacNicoll, Alan; Kelly, Mick [The Food and Environment Research Agency (United Kingdom); Aksoy, Hatice [TÜBİTAK Marmara Research Center, Food Institute (Turkey); Kramer, Evelien; Bouwmeester, Hans [RIKILT - Institute of Food Safety (Netherlands); Chaudhry, Qasim, E-mail: qasim.chaudhry@fera.gsi.gov.uk [The Food and Environment Research Agency (United Kingdom)

    2015-02-15

    Certain food additives may contain a sizeable fraction of particles in the nanoscale. However, little is known about the fate, behaviour and toxicological effects of orally-ingested nanoparticles. This study investigated the uptake and biodistribution of nano- and larger-sized titanium dioxide (TiO{sub 2}) using an in vitro model of gut epithelium and in vivo in rat. The results of the in vivo study showed that oral administration of 5 mg/kg body weight of TiO{sub 2} nano- or larger particles did not lead to any significant translocation of TiO{sub 2} (measured as titanium) either to blood, urine or to various organs in rat at any of the time intervals studied over a 96 h post-administration period. Different methods used for dispersing particles did not affect the uptake, and orally administered TiO{sub 2} was found excreted in the faeces over a period of time. The in vitro study provided further evidence for the lack of translocation of TiO{sub 2} across the gut epithelium model. The overall evidence from both in vivo and in vitro studies did not support that oral ingestion of nano- or larger particles of TiO{sub 2} via food would result in any significant internal exposure of the consumer to the nanoparticles. The dietary TiO{sub 2} nanoparticles are likely to be excreted in the faeces.

  16. Evaluation of BPA uptake in clear cell sarcoma (CCS) in vitro and development of an in vivo model of CCS for BNCT studies

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, T., E-mail: fujitaku@hp.pref.hyogo.jp [Department of Orthopaedic Surgery, Hyogo Cancer Center, Akashi 673-0021 (Japan); Andoh, T. [Faculty of Pharmaceutical Sciences and Cooperative Research Center of Life Sciences, Kobe Gakuin University, Kobe 650-8586 (Japan); Sudo, T. [Section of Translational Research, Hyogo Cancer Center, Akashi 673-0021 (Japan); Fujita, I.; Imabori, M. [Department of Orthopaedic Surgery, Hyogo Cancer Center, Akashi 673-0021 (Japan); Moritake, H. [Division of Pediatrics, University of Miyazaki, Miyazaki 889-1692 (Japan); Sugimoto, T. [Department of Pediatrics, Saiseikai Shigaken Hospital, Ritto 520-3046 (Japan); Sakuma, Y. [Department of Pathology, Hyogo Cancer Center, Akashi 673-0021 (Japan); Takeuchi, T. [Department of Pathology, Kochi Medical School, Nangoku 783-8505 (Japan); Sonobe, H. [Department of Pathology, Chugoku Central Hospital, Fukuyama 720-0001 (Japan); Epstein, Alan L. [Department of Pathology, Keck School of Medicine,University of Southern California, Los Angeles,CA 90033 (United States); Akisue, T. [Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Kirihata, M. [Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531 (Japan); Kurosaka, M. [Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe 650-0017 (Japan); Fukumori, Y.; Ichikawa, H. [Faculty of Pharmaceutical Sciences and Cooperative Research Center of Life Sciences, Kobe Gakuin University, Kobe 650-8586 (Japan)

    2011-12-15

    Clear cell sarcoma (CCS), a rare malignant tumor with a predilection for young adults, is of poor prognosis. Recently however, boron neutron capture therapy (BNCT) with the use of p-borono-L-phenylalanine (BPA) for malignant melanoma has provided good results. CCS also produces melanin; therefore, the uptake of BPA is the key to the application of BNCT to CCS. We describe, for the first time, the high accumulation of boron in CCS and the CCS tumor-bearing animal model generated for BNCT studies.

  17. Early uptake of HIV counselling and testing among pregnant women at different levels of health facilities – experiences from a community-based study in Northern Vietnam

    DEFF Research Database (Denmark)

    Nguyen Thi Thuy, Hanh; Gammeltoft, Tine; Rasch, Vibeke

    2011-01-01

    ABSTRACT: BACKGROUND: HIV counselling and testing for pregnant women is a key factor for successful prevention of mother to child transmission of HIV. Women's access to testing can be improved by scaling up the distribution of this service at all levels of health facilities. However, this strategy...... will only be effective if pregnant women are tested early and provided enough counselling. OBJECTIVE: To assess early uptake of HIV testing and the provision of HIV counselling among pregnant women who attend antenatal care at primary and higher level health facilities. METHODS: A community based study...

  18. Cervical Cancer Screening Service Uptake and Associated Factors among Age Eligible Women in Mekelle Zone, Northern Ethiopia, 2015: A Community Based Study Using Health Belief Model.

    Directory of Open Access Journals (Sweden)

    Hinsermu Bayu

    Full Text Available Cervical cancer is the third most common cancer among women worldwide, with about 500,000 new patients diagnosed and over 250,000 deaths every year. Cervical cancer screening offers protective benefits and is associated with a reduction in the incidence of invasive cervical cancer and cervical cancer mortality. But there is very low participation rate in screening for cervical cancer among low and middle-income countries.This study aimed to determine cervical cancer screening service uptake and its associated factor among age eligible women in Mekelle zone, northern Ethiopia, 2015.A community based cross-sectional study was conducted in Mekelle zone among age eligible women from February to June 2015. Systematic sampling technique was used to select 1286 women in to the study. A pre-tested structured questionnaire was used to collect relevant data. Data was entered and cleaned using EPINFO and analyzed using SPSS version 20 software package. Bivariate and Multivariate logistic regression was performed to assess association between dependent and independent variables with 95% CI and p-value less than 0.05 was set for association.The study revealed that among 1186 age eligible women, only 235(19.8% have been screened for cervical cancer. Age (AOR = 1.799, 95%CI = 1.182-2.739, history of multiple sexual partners (AOR = 1.635, 95%CI = 1.094-2.443, history of sexually transmitted disease (AOR = 1.635,95%CI = 1.094-2.443, HIV sero status (AOR = 5.614, 95%CI = 2.595-12.144, perceived susceptibility to cervical cancer (AOR = 2.225, 95%CI = 1.308-3.783, perceived barriers to premalignant cervical lesions screening (AOR = 2.256, 95%CI = 1.447-3.517 and knowledge on cervical cancer and screening (AOR = 2.355, 95%CI = 1.155-4.802 were significant predictors of cervical cancer screening service uptake.Magnitude of cervical cancer screening service uptake among age eligible women is still unacceptably low. Age of the women, history of multiple sexual partners

  19. Identifying and addressing barriers to uptake of voluntary medical male circumcision in Nyanza, Kenya among men 18-35: a qualitative study.

    Directory of Open Access Journals (Sweden)

    Emily Evens

    Full Text Available BACKGROUND: Uptake of VMMC among adult men has been lower than desired in Nyanza, Kenya. Previous research has identified several barriers to uptake but qualitative exploration of barriers is limited and evidence-informed interventions have not been fully developed. This study was conducted in 2012 to 1 increase understanding of barriers to VMMC and 2 to inform VMMC rollout through the identification of evidence-informed interventions among adult men at high risk of HIV in Nyanza Province, Kenya. METHODS: Focus groups (n = 8 and interviews were conducted with circumcised (n = 8 and uncircumcised men (n = 14 from the two districts in Nyanza, Kenya. Additional interviews were conducted with female partners (n = 20, health providers (n = 12, community leaders (n = 12 and employers (n = 12. Interview and focus group guides included questions about individual, interpersonal and societal barriers to VMMC uptake and ways to overcome them. Inductive thematic coding and analysis were conducted through a standard iterative process. RESULTS: Two primary concerns with VMMC emerged 1 financial issues including missing work, losing income during the procedure and healing and family survival during the recovery period and 2 fear of pain during and after the procedure. Key interventions to address financial concerns included: a food or cash transfer, education on saving and employer-based benefits. Interventions to address concerns about pain included refining the content of demand creation and counseling messages about pain and improving the ways these messages are delivered. CONCLUSIONS: Men need accurate and detailed information on what to expect during and after VMMC regarding both pain and time away from work. This information should be incorporated into demand creation activities for men considering circumcision. Media content should frankly and correctly address these concerns. Study findings support scale up and/or further improvement of these ongoing

  20. Uptake of a new meningitis vaccination programme amongst first-year undergraduate students in the United Kingdom: A cross-sectional study.

    Science.gov (United States)

    Blagden, Sarah; Seddon, Daniel; Hungerford, Daniel; Stanistreet, Debbi

    2017-01-01

    In 2015 meningococcal group W was declared endemic in the UK, with the meningococcal ACWY vaccination (MenACWY) subsequently introduced amongst adolescents and first-year university students. This study aimed to determine MenACWY uptake amongst students and to evaluate how this was influenced by demographics and via the Health Belief Model (HBM). This was a cross-sectional study conducted at a British university amongst first-year undergraduate students aged 18-25 years. Data collection was via an electronic questionnaire encompassing demographics, the HBM and vaccination status. Univariable analysis of the associations between demographics, health beliefs and vaccination was performed, followed by multiple logistic regression. 401 participants were included in analysis. Vaccine uptake was 68.1%. Variables independently associated with vaccination upon multiple regression were age, gap-year, perceived effectiveness of the vaccine and knowledge about risk of meningitis. Compared to 18 year-olds, the odds of vaccination were reduced for 19 year-olds (aOR = 0.087, 95% CI = 0.010-0.729), 20 year-olds (aOR = 0.019, 95% CI = 0.002-0.161) and 21-25 year-olds (aOR = 0.003, 95% CI = year (aOR = 2.939, 95% CI = 1.329-6.501), higher perceived vaccine effectiveness (aOR = 3.555, 95% CI = 1.787-7.073) and knowledge about meningitis risk (aOR = 2.481, 95% CI = 1.165-5.287) were independently associated with increased uptake. MenACWY uptake amongst students in this study and in other sources is above the national coverage for all adolescents (35.3%), indicating that this vaccination programme may be increasing health inequalities. Older students are less likely to become vaccinated due to differing vaccination policy in this age-group. In future, strategies that focus on specific student cohorts and that highlight vaccine effectiveness and the risk of meningitis should be considered. National evaluation of this vaccination programme is recommended to clarify its impact on health

  1. Normal cerebral FDG uptake during childhood

    Energy Technology Data Exchange (ETDEWEB)

    London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Disciplines of Imaging and Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia)

    2014-04-15

    Current understanding of cerebral FDG uptake during childhood originates from a small number of studies in patients with neurological abnormalities. Our aim was to describe cerebral FDG uptake in a dataset of FDG PET scans in children more likely to represent a normal population. We reviewed cerebral FDG PET scans in children up to 16 years of age with suspected/proven extracranial malignancies and the following exclusions: central nervous system metastases, previous malignancies, previous chemotherapy or radiotherapy, development of cerebral metastases during therapy, neurological conditions, taking antiepileptic medication or medications likely to interfere with cerebral metabolism, and general anaesthesia within 24 h. White matter, basal ganglia, thalamus and the cerebellar cortex were analysed using regional SUV{sub max}, and the cerebral cortex, basal ganglia, thalamus and cerebellum were analysed using a regional relative uptake analysis in comparison to maximal cortical uptake. Scans from 30 patients (age range 11 months to 16 years, mean age 10 years 5 months) were included. All regions showed increasing SUV{sub max} with age. The parietal, occipital, lateral temporal and medial temporal lobes showed lower rates of increasing FDG uptake causing changing patterns of regional FDG uptake during childhood. The cortical regions showing the most intense uptake in early childhood were the parietal and occipital lobes. At approximately 7 years of age these regions had relatively less uptake than the frontal lobes and at approximately 10 years of age these regions had relatively less uptake than the thalamus. Relative FDG uptake in the brain has not reached an adult pattern by 1 year of age, but continues to change up to 16 years of age. The changing pattern is due to different regional rates of increasing cortical FDG uptake, which is less rapid in the parietal, occipital and temporal lobes than in the frontal lobes. (orig.)

  2. Further studies on the erythrocyte uptake of lead in vitro in amyotrophic lateral sclerosis (ALS) patients and controls. Abnormal erythrocyte fragility in ALS.

    Science.gov (United States)

    Ronnevi, L O; Conradi, S; Nise, G

    1982-01-01

    Following our earlier observations on increased plasma concentrations of lead in amyotrophic lateral sclerosis (ALS), the erythrocyte uptake of lead from plasma has been studied in vitro. Whole-blood from ALS patients and controls was incubated after the addition of lead (0.6 mumol/l whole-blood) and plasma lead concentrations were repeatedly determined. Incubation was continued until haemolysis developed. Fairly stable plasma lead concentrations were established at, on the average, 0.5-0.6 mumol/l after 10-30 min and persisted throughout the incubation with no significant difference between ALS- and control samples. Unexpectedly, it was also observed that haemolysis occurred significantly earlier in the ALS- than in the control samples. Plateau levels in plasma lead concentration of the same order as in the present experiments have been observed both in ALS- and control samples in previous experiments with the same technique, where the lead dose added was twice as high, and these plateau levels were about 10 times higher than those observed in vivo in ALS patients and controls. It is therefore suggested that the final plasma lead concentrations in vivo is established by factors other than the erythrocyte uptake and it is improbable that the differences between ALS patients and controls in plasma lead concentration are associated with differences in the degree of lead uptake by the red cells. The increased plasma lead concentrations in ALS patients may instead be caused by increased fragility of the erythrocytes, as manifested by the earlier occurrence of haemolysis in the present experiments. The observation of increased red cell fragility is, however, also of interest as a possible manifestation of a generalized membrane defect.

  3. Predictors of Uptake and Timeliness of Newly Introduced Pneumococcal and Rotavirus Vaccines, and of Measles Vaccine in Rural Malawi: A Population Cohort Study.

    Directory of Open Access Journals (Sweden)

    Hazzie Mvula

    Full Text Available Malawi introduced pneumococcal conjugate vaccine (PCV13 and monovalent rotavirus vaccine (RV1 in 2011 and 2012 respectively, and is planning the introduction of a second-dose measles vaccine (MV. We assessed predictors of availability, uptake and timeliness of these vaccines in a rural Malawian setting.Commencing on the first date of PCV13 eligibility we conducted a prospective population-based birth cohort study of 2,616 children under demographic surveillance in Karonga District, northern Malawi who were eligible for PCV13, or from the date of RV1 introduction both PCV13 and RV1. Potential predictors of vaccine uptake and timeliness for PCV13, RV1 and MV were analysed respectively using robust Poisson and Cox regression.Vaccine coverage was high for all vaccines, ranging from 86.9% for RV1 dose 2 to 95.4% for PCV13 dose 1. Median time delay for PCV13 dose 1 was 17 days (IQR 7-36, 19 days (IQR 8-36 for RV1 dose 1 and 20 days (IQR 3-46 for MV. Infants born to lower educated or farming mothers and those living further away from the road or clinic were at greater risk of being not fully vaccinated and being vaccinated late. Delays in vaccination were also associated with non-facility birth. Vaccine stock-outs resulted in both a delay in vaccine timeliness and in a decrease in completion of schedule.Despite high vaccination coverage in this setting, delays in vaccination were common. We identified programmatic and socio-demographic risk factors for uptake and timeliness of vaccination. Understanding who remains most vulnerable to be unvaccinated allows for focussed delivery thereby increasing population coverage and maximising the equitable benefits of universal vaccination programmes.

  4. Direct relationship between cell density and FDG uptake in asymptomatic aortic aneurysm close to surgical threshold: an in vivo and in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Cecilia [CNR Institute of Bioimaging and Molecular Physiology, Milan, Genoa Section, Genoa (Italy); Oftalmologia e Genetica dell' Universita di Genova, Dipartimento di Neuroscienze, Genoa (Italy); Morbelli, Silvia; Armonino, Riccardo; Riondato, Mattia; Massollo, Michela; Augeri, Carla; Fiz, Francesco; Sambuceti, Gianmario [University of Genoa, Department Internal Medicine, Chair of Nuclear Medicine, Genoa (Italy); Spinella, Giovanni; Pane, Bianca; Palmieri, Daniela; Palombo, Domenico [San Martino University Hospital, University of Genoa, Division of Vascular and Endovascular Surgery, Genoa (Italy); Sarocchi, Francesca; Abete, Luca; Fulcheri, Ezio [University of Genoa, Department of Surgical and Diagnostic Sciences, Pathology, Genoa (Italy); Ghigliotti, Giorgio [University of Genoa, Department of Internal Medicine, Chair of Cardiology, Genoa (Italy); Cittadini, Giuseppe [Hospital San Martino, Department of Radiology, Genoa (Italy)

    2012-01-15

    Conflicting results have been reported about the clinical value of fluorodeoxyglucose (FDG) imaging in predicting the risk of rupture of abdominal aortic aneurysm (AAA). The present study tests the hypothesis that FDG uptake is low in asymptomatic noninflammatory AAA due to the low cell density in aneurysmal walls. Positron emission tomography (PET)/CT imaging was performed in 12 consecutive candidates for AAA surgical repair and in 12 age- and sex-matched controls. At intervention, aneurysmal walls were cut into three sequential blocks. Block A was frozen to cut three 5-{mu}m slices for incubation with 2-3 MBq of FDG for 5 min. Block C was first incubated with the same tracer solution for the same time and subsequently frozen to cut three 5-{mu}m slices. Autoradiographic images were coregistered with immunohistochemical pictures of cell density, type and DNA synthesis as assessed on block B. No visible uptake in abdominal aorta occurred in any patient or control subject. Immunohistochemistry documented a severe loss of wall structure, with low numbers of cells. Tracer retention directly correlated with overall cell density and with prevalence of cells synthesizing DNA. The metabolic nature of FDG uptake was confirmed by the selective effect of preliminary freezing that decreased tracer content by 90% in regions with high cell density and only by 34% in cold acellular areas. The loss of tissue structure and the marked decrease in cell density account for the low prevalence of positive findings at FDG PET imaging, at least in asymptomatic patients bearing AAAs whose diameter is close to surgical indication. (orig.)

  5. Reproducibility of O-(2-{sup 18}F-fluoroethyl)-L-tyrosine uptake kinetics in brain tumors and influence of corticoid therapy: an experimental study in rat gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Stegmayr, Carina; Schoeneck, Michael; Oliveira, Dennis; Willuweit, Antje [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); Filss, Christian; Coenen, Heinz H.; Langen, Karl-Josef [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Galldiks, Norbert [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Cologne, Department of Neurology, Cologne (Germany); Shah, N. Jon [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Juelich (Germany)

    2016-06-15

    Positron emission tomography (PET) using O-(2-{sup 18}F-fluoroethyl)-L-tyrosine ({sup 18}F-FET) is a well-established method for the diagnostics of brain tumors. This study investigates reproducibility of {sup 18}F-FET uptake kinetics in rat gliomas and the influence of the frequently used dexamethasone (Dex) therapy. F98 glioma or 9L gliosarcoma cells were implanted into the striatum of 31 Fischer rats. After 10-11 days of tumor growth, the animals underwent dynamic PET after injection of {sup 18}F-FET (baseline). Thereafter, animals were divided into a control group and a group receiving Dex injections, and all animals were reinvestigated 2 days later. Tumor-to-brain ratios (TBR) of {sup 18}F-FET uptake (18-61 min p.i.) and the slope of the time-activity-curves (TAC) (18-61 min p.i.) were evaluated using a Volume-of-Interest (VOI) analysis. Data were analyzed by two-way repeated measures ANOVA and reproducibility by the intraclass correlation coefficient (ICC). The slope of the tumor TACs showed high reproducibility with an ICC of 0.93. A systematic increase of the TBR in the repeated scans was noted (3.7 ± 2.8 %; p < 0.01), and appeared to be related to tumor growth as indicated by a significant correlation of TBR and tumor volume (r = 0.77; p < 0.0001). After correction for tumor growth TBR showed high longitudinal stability with an ICC of 0.84. Dex treatment induced a significant decrease of the TBR (-8.2 ± 6.1 %; p < 0.03), but did not influence the slope of the tumor TAC. TBR of {sup 18}F-FET uptake and tracer kinetics in brain tumors showed high longitudinal stability. Dex therapy may induce a minor decrease of the TBR; this needs further investigation. (orig.)

  6. Uptake, Accuracy, Safety, and Linkage into Care over Two Years of Promoting Annual Self-Testing for HIV in Blantyre, Malawi: A Community-Based Prospective Study.

    Directory of Open Access Journals (Sweden)

    Augustine T Choko

    2015-09-01

    Full Text Available Home-based HIV testing and counselling (HTC achieves high uptake, but is difficult and expensive to implement and sustain. We investigated a novel alternative based on HIV self-testing (HIVST. The aim was to evaluate the uptake of testing, accuracy, linkage into care, and health outcomes when highly convenient and flexible but supported access to HIVST kits was provided to a well-defined and closely monitored population.Following enumeration of 14 neighbourhoods in urban Blantyre, Malawi, trained resident volunteer-counsellors offered oral HIVST kits (OraQuick ADVANCE Rapid HIV-1/2 Antibody Test to adult (≥16 y old residents (n = 16,660 and reported community events, with all deaths investigated by verbal autopsy. Written and demonstrated instructions, pre- and post-test counselling, and facilitated HIV care assessment were provided, with a request to return kits and a self-completed questionnaire. Accuracy, residency, and a study-imposed requirement to limit HIVST to one test per year were monitored by home visits in a systematic quality assurance (QA sample. Overall, 14,004 (crude uptake 83.8%, revised to 76.5% to account for population turnover residents self-tested during months 1-12, with adolescents (16-19 y most likely to test. 10,614/14,004 (75.8% participants shared results with volunteer-counsellors. Of 1,257 (11.8% HIV-positive participants, 26.0% were already on antiretroviral therapy, and 524 (linkage 56.3% newly accessed care with a median CD4 count of 250 cells/μl (interquartile range 159-426. HIVST uptake in months 13-24 was more rapid (70.9% uptake by 6 mo, with fewer (7.3%, 95% CI 6.8%-7.8% positive participants. Being "forced to test", usually by a main partner, was reported by 2.9% (95% CI 2.6%-3.2% of 10,017 questionnaire respondents in months 1-12, but satisfaction with HIVST (94.4% remained high. No HIVST-related partner violence or suicides were reported. HIVST and repeat HTC results agreed in 1

  7. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... uptake are not performed on patients who are pregnant because of the risk of exposing the fetus to radiation. These tests are also not recommended for breastfeeding women. Nuclear medicine procedures can be time consuming. It ...

  8. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... is taken by mouth, in either liquid or capsule form, it is typically swallowed up to 24 ... I-123 or I-131) in liquid or capsule form to swallow. The thyroid uptake will begin ...

  9. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... which are encased in metal and plastic and most often shaped like a box, attached to a ... will I experience during and after the procedure? Most thyroid scan and thyroid uptake procedures are painless. ...

  10. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... scan and uptake uses small amounts of radioactive materials called radiotracers, a special camera and a computer ... last two months that used iodine-based contrast material. Your doctor will instruct you on how to ...

  11. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... eat for several hours before your exam because eating can affect the accuracy of the uptake measurement. ... often unattainable using other imaging procedures. For many diseases, nuclear medicine scans yield the most useful information ...

  12. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... RAIU) is also known as a thyroid uptake. It is a measurement of thyroid function, but does ... they offer the potential to identify disease in its earliest stages as well as a patient’s immediate ...

  13. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... time for the imaging to begin, you will sit in a chair facing a stationary probe positioned ... counter used for thyroid uptake exams. The patient sits with the camera directed at the neck for ...

  14. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... for several hours before your exam because eating can affect the accuracy of the uptake measurement. Jewelry ... small hand-held device resembling a microphone that can detect and measure the amount of the radiotracer ...

  15. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... information about your thyroid’s size, shape, position and function that is often unattainable using other imaging procedures. ... thyroid uptake. It is a measurement of thyroid function, but does not involve imaging. Nuclear medicine is ...

  16. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... A thyroid scan is a type of nuclear medicine imaging. The radioactive iodine uptake test (RAIU) is ... thyroid function, but does not involve imaging. Nuclear medicine is a branch of medical imaging that uses ...

  17. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... RAIU) is also known as a thyroid uptake. It is a measurement of thyroid function, but does ... they offer the potential to identify disease in its earliest stages as well as a patient’s immediate ...

  18. Tuberculosis patients' reasons for, and suggestions to address non-uptake of HIV testing: a cross-sectional study in the Free State Province, South Africa

    Directory of Open Access Journals (Sweden)

    Wouters Edwin

    2011-05-01

    Full Text Available Abstract Background South Africa endorses the global policy shift from primarily client-initiated voluntary counselling and testing (VCT to routine/provider-initiated testing and counselling (PITC. The reason for this policy shift has been to facilitate uptake of HIV testing amongst at-risk populations in high-prevalence settings. Despite ostensible implementation of routine/PITC, uptake amongst tuberculosis (TB patients in this country remains a challenge. This study presents the reasons that non-tested TB patients offered for their refusal of HIV testing and reflects on all TB patients' suggestions as to how this situation may be alleviated. Methods In February-March 2008, a cross-sectional survey was conducted amongst 600 TB patients across 61 primary health care facilities in four sub-districts in the Free State. Patient selection was done proportionally to the numbers registered at each facility in 2007. Data were subjected to bivariate tests and content analysis of open-ended questions. Results Almost one-third (32.5% of the respondents reported that they had not undertaken HIV testing, with the most often offered explanation being that they were 'undecided' (37.0%. Other self-reported reasons for non-uptake included: fear (e.g. of testing HIV-positive, 19.0%; perception of being at low risk of HIV infection (13.4%; desire first to deal with TB 'on its own' (12.5%; and because HIV testing had not been offered to them (12.0%. Many patients expressed the need for support and motivation not only from health care workers (33.3%, but also from their significant others (56.6%. Patients further expressed a need for (increased dissemination of TB-HIV information by health care workers (46.1%. Conclusions Patients did not undergo HIV testing for various patient-/individual-related reasons. Non-uptake of HIV testing was also due to health system limitations such as the non-offer of HIV testing. Other measures may be necessary to supplement routine

  19. Advances in the Studies on Water Uptake by Plant Roots%植物根系吸水机理的研究进展

    Institute of Scientific and Technical Information of China (English)

    赵长星; 邓西平; 张岁岐; 叶清; Ernst STEUDLE; 山仑

    2004-01-01

    近年来,植物根系吸水机理在细胞、组织和整体水平上的研究进展非常迅速,对阐明植物抗旱机制及其高效利用有限水资源途径的探讨具有重要意义.本文主要对植物根的复合结构和根系在土壤中的分布、根系中水流性质等方面的最新研究状况进行了概述,特别详细地论述了水通道蛋白的表达及功能与根系中水分运动的关系、以及根系输水的调节和根系吸水过程中的信号传导方面的研究动态,并且评价了根的复合运输模型和根系吸水的数学模型等,最后就其可能生理意义及其应用前景作了评述.%In the past decade, our understanding of the mechanisms of water uptake by plant roots at the cell, tissue, and whole-plant levels rapidly progressed due to the introduction of new techniques and concepts. Some aspects of this work were reviewed, mainly including the composite structure of roots and effects of the distribution of roots in the soil. The nature of water flow in plant roots was discussed. A link was provided between root hydraulics and the expression and function of aquaporins. This was related to the regulation of water transport and to the signaling between roots and shoots. The composite transport model of root was mentioned which represents a physical model of water uptake. This is part of a comprehensive analysis of recent findings of studies on water uptake by plant roots and contributes to our current understanding of the basic mechanisms that govern the water uptake by roots.

  20. Study on Characteristics of Calcium Uptake by Young Fruit of Apple (Malus pumila) and Its Regulation by Hormone

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Field trial, pot experiment with 45Ca tracer, plant analysis were used to investigate the characteristics of calcium uptake by young fruit of apple and its regulation by IAA, GA and NAA. The results indicated that calcium should be applied directly on the surface of young fruits because calcium applied on leaves could be hardly transfered to fruits. The proper Ca applying period was the first month of young fruits formation, and the proper concentration of CaCl2 applied was 0. 5%. Applying Ca directly on the surface of young fruits could increase the weight and quality of fruits. The process of transfering Ca2+ from fruit surface into pulp tissue could be accelerated by IAA, GA or NAA, which also led to an increment on 2% HOAc extractable Ca. Meanwhile, the Ca existed in the stalk and leaves could be strongly transported into fruits by applying IAA on the fruit surface, resulting in too much accumulation of Ca in fruit and bad quality of fruit, while no such sighs were observed with GA or NAA.

  1. C nuclear magnetic resonance study of acetate incorporation into malate during ca-uptake by isolated leaf tissues.

    Science.gov (United States)

    Borchert, R; Everett, G W

    1987-07-01

    (13)C Nuclear magnetic resonance spectroscopy of leaflets of Gleditsia triacanthos and Albizia julibrisin was used to determine the fate of acetate taken up during the absorption of calcium from (13)C-labeled Ca-acetate solution. Small amounts of acetate accumulated temporarily in the leaf tissues, but the bulk of acetate was incorporated into malate. The initial rate of malate synthesis was very low, but increased rapidly during acetate treatment and reached its maximum after 8 hours; the enzymes involved in malate synthesis thus appear to be substrate induced. Use of acetate-2-(13)C yielded malate labeled in C-3, indicating that vacuolar malate accumulating during Ca-uptake might be synthesized via malate synthase from acetate and glyoxalate. However, a source of glyoxalate condensing with acetate during malate synthesis could not be identified. Glycolate produced in photorespiration is an unlikely source, because glycolate-2-(13)C was absorbed and metabolized by the leaf tissues into products of the glycolate pathway, but was not a major precursor in malate synthesis. Malate synthesis via the glyoxalate cycle is also unlikely, because no evidence for the recycling of a (13)C-labeled 4-carbon organic acid was found. Malate synthesis in the leaflets of Gleditsia and Albizia thus appears to involve the inducible condensation of acetate with a 2-carbon compound of unidentified nature and origin.

  2. 13C Nuclear Magnetic Resonance Study of Acetate Incorporation into Malate During Ca2+-Uptake by Isolated Leaf Tissues 1

    Science.gov (United States)

    Borchert, Rolf; Everett, Grover W.

    1987-01-01

    13C Nuclear magnetic resonance spectroscopy of leaflets of Gleditsia triacanthos and Albizia julibrisin was used to determine the fate of acetate taken up during the absorption of calcium from 13C-labeled Ca-acetate solution. Small amounts of acetate accumulated temporarily in the leaf tissues, but the bulk of acetate was incorporated into malate. The initial rate of malate synthesis was very low, but increased rapidly during acetate treatment and reached its maximum after 8 hours; the enzymes involved in malate synthesis thus appear to be substrate induced. Use of acetate-2-13C yielded malate labeled in C-3, indicating that vacuolar malate accumulating during Ca-uptake might be synthesized via malate synthase from acetate and glyoxalate. However, a source of glyoxalate condensing with acetate during malate synthesis could not be identified. Glycolate produced in photorespiration is an unlikely source, because glycolate-2-13C was absorbed and metabolized by the leaf tissues into products of the glycolate pathway, but was not a major precursor in malate synthesis. Malate synthesis via the glyoxalate cycle is also unlikely, because no evidence for the recycling of a 13C-labeled 4-carbon organic acid was found. Malate synthesis in the leaflets of Gleditsia and Albizia thus appears to involve the inducible condensation of acetate with a 2-carbon compound of unidentified nature and origin. PMID:16665548

  3. Immunocytochemistry for amoxicillin and its use for studying uptake of the drug in the intestine, liver, and kidney of rats.

    Science.gov (United States)

    Fujiwara, Kunio; Shin, Masashi; Miyazaki, Tsubasa; Maruta, Yasuhiro

    2011-01-01

    Specific transport systems for penicillins have been recognized, but their in vivo role in the context of other transporters remains unclear. We produced a serum against amoxicillin (anti-AMPC) conjugated to albumin with glutaraldehyde. The antiserum was specific for AMPC and ampicillin (ABPC) but cross-reacted weakly with cephalexin. This enabled us to develop an immunocytochemical (ICC) method for detecting the uptake of AMPC in the rat intestine, liver, and kidney. Three hours after a single oral administration of AMPC, the ICC method revealed that AMPC distributed to a high degree in the microvilli, nuclei, and cytoplasm of the absorptive epithelial cells of the intestine. AMPC distributed in the cytoplasm and nuclei of the hepatocytes in a characteristic granular morphology on the bile capillaries, and in addition, AMPC adsorption was observed on the luminal surface of the capillaries, intercalated portions, and interlobular bile ducts on the bile flow. Almost no AMPC could be detected 6 h postadministration in either the intestine or the liver. Meanwhile, in the kidney, AMPC persisted until 12 h postadministration to a high degree in the proximal tubules, especially in the S3 segment cells in the tubular lumen, in which numerous small bodies that strongly reacted with the antibody were observed. All these sites of AMPC accumulation correspond well to specific sites where certain transporter systems for penicillins occur, suggesting that AMPC is actually and actively absorbed, eliminated, or excreted at these sites, possibly through such certain penicillin transporters.

  4. [Mechanism Study of the Smectite-OR-SH Compound for Reducing Cadmium Uptake by Plants in Contaminated Soils].

    Science.gov (United States)

    Zeng, Yan-jun; Zhou, Zhi-jun; Zhao, Qiu-xiang

    2015-06-01

    Adsorption and desorption experiments, pot experiments and characterization test were performed to investigate the immobilization effect and mechanism of the smectite-OR-SH compound for reducing cadmium uptake by plants in contaminated soils. The results showed that the saturated adsorption capacity for the adsorption of Cd2+ on smectite raised distinctly after functionalized. The adsorption of Cd2+ on smectite-OR-SH compound was very stable and it was difficult for Cd2+ to be desorbed from it. Crop yields promoted differently in original soil, Cd 3 mg x kg(-1) soil and Cd 10 mg x kg(-1) soil after adding the smectite-OR-SH compound. And the cadmium content of the cabbage reduced 61.00%, 62.10% and 83.73% respectively compare with the control. Characterization test analysis showed that Cd was adsorbed by the compound successfully and ligand interaction occurred between Cd and the thiol group. Floc amount on the compound surface increased correspondingly. In addition to electrostatic adsorption, ion exchange and hydroxyl ligand adsorption, the reaction mechanism of smectite-OR-SH compound with Cd was mainly sulfhydryl ligand adsorption.

  5. Capturing Individual Uptake: Toward a Disruptive Research Methodology

    Science.gov (United States)

    Bastian, Heather

    2015-01-01

    This article presents and illustrates a qualitative research methodology for studies of uptake. It does so by articulating a theoretical framework for qualitative investigations of uptake and detailing a research study designed to invoke and capture students' uptakes in a first-year writing classroom. The research design sought to make uptake…

  6. Not all that glitters is gold-Electron microscopy study on uptake of gold nanoparticles in Daphnia magna and related artifacts.

    Science.gov (United States)

    Jensen, Louise Helene Søgaard; Skjolding, Lars Michael; Thit, Amalie; Sørensen, Sara Nørgaard; Købler, Carsten; Mølhave, Kristian; Baun, Anders

    2017-06-01

    Increasing use of engineered nanoparticles has led to extensive research into their potential hazards to the environment and human health. Cellular uptake from the gut is sparsely investigated, and microscopy techniques applied for uptake studies can result in misinterpretations. Various microscopy techniques were used to investigate internalization of 10-nm gold nanoparticles in Daphnia magna gut lumen and gut epithelial cells following 24-h exposure and outline potential artifacts (i.e., high-contrast precipitates from sample preparation related to these techniques). Light sheet microscopy confirmed accumulation of gold nanoparticles in the gut lumen. Scanning transmission electron microscopy and elemental analysis revealed gold nanoparticles attached to the microvilli of gut cells. Interestingly, the peritrophic membrane appeared to act as a semipermeable barrier between the lumen and the gut epithelium, permitting only single particles through. Structures resembling nanoparticles were also observed inside gut cells. Elemental analysis could not verify these to be gold, and they were likely artifacts from the preparation, such as osmium and iron. Importantly, gold nanoparticles were found inside holocrine cells with disrupted membranes. Thus, false-positive observations of nanoparticle internalization may result from either preparation artifacts or mistaking disrupted cells for intact cells. These findings emphasize the importance of cell integrity and combining elemental analysis with the localization of internalized nanoparticles using transmission electron microscopy. Environ Toxicol Chem 2017;36:1503-1509. © 2016 SETAC. © 2016 SETAC.

  7. Screening uptake rates and the clinical and cost effectiveness of screening for gestational diabetes mellitus in primary versus secondary care: study protocol for a randomised controlled trial.

    LENUS (Irish Health Repository)

    O Dea, Angela

    2014-01-17

    The risks associated with gestational diabetes mellitus (GDM) are well recognized, and there is increasing evidence to support treatment of the condition. However, clear guidance on the ideal approach to screening for GDM is lacking. Professional groups continue to debate whether selective screening (based on risk factors) or universal screening is the most appropriate approach. Additionally, there is ongoing debate about what levels of glucose abnormalities during pregnancy respond best to treatment and which maternal and neonatal outcomes benefit most from treatment. Furthermore, the implications of possible screening options on health care costs are not well established. In response to this uncertainty there have been repeated calls for well-designed, randomised trials to determine the efficacy of screening, diagnosis, and management plans for GDM. We describe a randomised controlled trial to investigate screening uptake rates and the clinical and cost effectiveness of screening in primary versus secondary care settings. The objective of this study is to assess screening uptake rates, and the clinical and cost effectiveness of screening for GDM in primary versus secondary care.

  8. Renoprotective effect of erdosteine in rats against gentamicin nephrotoxicity: a comparison of 99mTc-DMSA uptake with biochemical studies.

    Science.gov (United States)

    Cabuk, Mehmet; Gurel, Ahmet; Sen, Feyza; Demircan, Nejat

    2008-01-01

    Erdosteine is a mucolytic agent having antioxidant properties through its active metabolites in acute injuries induced by pharmacological drugs. This study was designed to investigate the renoprotective potential of Erdosteine against gentamicin (GM)-induced renal dysfunction by using Technetium-99 m dimercaptosuccinic acid (Tc-99 m DMSA) uptake and scintigraphy in rats. For this purpose, male Wistar rats were randomly allotted into one of the four experimental groups: Control, Erdosteine, GM, and GM + Erdosteine groups. GM and GM + Erdosteine groups received 100 mg/kg GM intramuscularly for 6 days. In addition, Erdosteine and GM + Erdosteine groups received 50 mg/kg Erdosteine orally for 6 days. Renal function tests were assessed by serum blood urea nitrogen (BUN), creatinine levels, as well as scintigraphic and tissue radioactivity measurements with Tc-99 m DMSA. Renal oxidative damage was determined by renal malondialdehyde (MDA) levels, by antioxidant enzyme activities; superoxide dismutase (SOD) and catalase (CAT) and activities of oxidant enzymes; xanthine oxidase (XO) and myeloperoxidase (MPO). GM administration resulted in marked renal lipid peroxidation, increased XO and MPO activities and decreased antioxidant enzyme activities. GM + Erdosteine group significantly had lower MDA levels, higher SOD and CAT activities and lower XO and MPO activities, when compared to GM. Also GM + Erdosteine had lower levels of serum BUN, creatinine and higher renal tissue Tc-99 m DMSA uptake and radioactivity with respect to GM. In conclusion, our results supported a protective role of Erdosteine in nephrotoxicity associated with GM treatment.

  9. Preconception care for women with type 1 or type 2 diabetes mellitus: a mixed-methods study exploring uptake of preconception care.

    Science.gov (United States)

    Earle, Sarah; Tariq, Anisah; Komaromy, Carol; Lloyd, Cathy E; Karamat, M Ali; Webb, Jackie; Gill, Paramjit S

    2017-03-01

    Diabetes mellitus is a global health problem and one of the most common medical conditions in pregnancy. A wide range of modifiable risk factors are associated with diabetes mellitus in pregnancy, and it is widely acknowledged that preconception care (PCC) is beneficial for women with pre-existing diabetes mellitus. However, uptake of PCC services is low. To systematically review qualitative research on PCC for women with pre-existing diabetes mellitus of childbearing age, identify facilitators of and barriers to uptake of PCC and establish themes and gaps in knowledge. Through qualitative interviews explore views on the provision of, and facilitators of and barriers to the uptake of, PCC. Mixed methods encompassing a systematic review and qualitative interviews. Two secondary care sites and 11 primary care sites. Women of childbearing age with pre-existing type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) of white British or Pakistani origin. None. A narrative synthesis of the literature using thematic analysis and a thematic analysis of the qualitative interview data using the method of constant comparison. Eighteen qualitative studies were included in the systematic review and a quality appraisal was carried out using relevant criteria for qualitative research appraisal, including a narrative summary of study quality. Twelve interviews with women with pre-existing T1DM or T2DM were carried out. This fell short of the original aim of interviewing 48 women owing to challenges in recruitment, especially in primary care. A synthesis of these data shows that uptake of PCC is influenced by a range of factors, including the complexity of pregnancy planning, the skill and expertise of health professionals who provide care to women with diabetes mellitus, the role of health professionals in the delivery of PCC, and the quality of relationships between women and health professionals. Owing to significant challenges with recruitment of participants

  10. Maternal education, empowerment, economic status and child polio vaccination uptake in Pakistan: a population based cross sectional study

    Science.gov (United States)

    Zaheer, Sidra; Shafique, Kashif

    2017-01-01

    Objectives To explore the association of maternal education and empowerment with childhood polio vaccination using nationally representative data of Pakistani mothers in a reproductive age group. Design Cross-sectional. Setting Secondary analysis of Pakistan Demographic and Health Survey (PDHS), 2012–2013 data was performed. Participants Of the 13 558 mothers included in the survey sample, 6982 mothers were able to provide information regarding polio vaccinations. Main outcome measures Polio vaccination coverage among children aged up to 5 years was categorised as complete vaccination (all four oral polio vaccine (OPV) doses), incomplete vaccination, and no vaccination (zero OPV dose received). Mothers' empowerment status was assessed using standard ‘Measure DHS’ questions regarding their involvement in decision-making related to health, household possessions and visits among family and friends. Education was categorised as no education, primary, secondary and higher education. Results of multinomial regression analyses were reported as adjusted OR with 95% CI. We adjusted for age, wealth index, urban/rural residence, place of delivery, and antenatal and postnatal visits. Results Only 56.4% (n=3936) of the children received complete polio vaccination. Women with no education had significantly higher odds of their child receiving no polio vaccination (OR 2.34, 95% CI 1.05 to 5.18; pvaccination (OR 1.40, 95% CI 1.04 to 1.87; pchild for any polio vaccination (OR 1.58, 95% CI 1.17 to 2.12; pvaccination (OR 1.18, 95% CI 1.00 to 1.41; p=0.04). Conclusions Illiteracy, socioeconomic status and empowerment of women remained significant factors linked to poorer uptake of routine polio vaccination. PMID:28283489

  11. Maternal education, empowerment, economic status and child polio vaccination uptake in Pakistan: a population based cross sectional study.

    Science.gov (United States)

    Khan, Muhammad Tahir; Zaheer, Sidra; Shafique, Kashif

    2017-03-10

    To explore the association of maternal education and empowerment with childhood polio vaccination using nationally representative data of Pakistani mothers in a reproductive age group. Cross-sectional. Secondary analysis of Pakistan Demographic and Health Survey (PDHS), 2012-2013 data was performed. Of the 13 558 mothers included in the survey sample, 6982 mothers were able to provide information regarding polio vaccinations. Polio vaccination coverage among children aged up to 5 years was categorised as complete vaccination (all four oral polio vaccine (OPV) doses), incomplete vaccination, and no vaccination (zero OPV dose received). Mothers' empowerment status was assessed using standard 'Measure DHS' questions regarding their involvement in decision-making related to health, household possessions and visits among family and friends. Education was categorised as no education, primary, secondary and higher education. Results of multinomial regression analyses were reported as adjusted OR with 95% CI. We adjusted for age, wealth index, urban/rural residence, place of delivery, and antenatal and postnatal visits. Only 56.4% (n=3936) of the children received complete polio vaccination. Women with no education had significantly higher odds of their child receiving no polio vaccination (OR 2.34, 95% CI 1.05 to 5.18; pwomen also had significantly higher odds of not taking their child for any polio vaccination (OR 1.58, 95% CI 1.17 to 2.12; pempowerment of women remained significant factors linked to poorer uptake of routine polio vaccination. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. Plant uptake of dual-labeled organic N biased by inorganic C uptake

    DEFF Research Database (Denmark)

    Rasmussen, Jim; Sauheitl, Leopold; Eriksen, Jørgen;

    2010-01-01

    Direct plant uptake of organic nitrogen (N) is often studied using the dual-labeling approach (15N + 13C or 15N + 14C). However, the method might be hampered by uptake of labeled inorganic carbon (C) produced by mineralization of labeled organic compounds. Here we report the results from a triple...... glycine or CO2-3 , but found no differences in uptake rates between these C-sources. The uptake of inorganic C to the shoot tissue was higher for maize grown in full light compared to shading, which indicates a passive uptake of inorganic C with water. We conclude that uptake of inorganic C produced...... labeling experiment (15N + 13C + 14C) investigating whether root uptake of labeled inorganic C can bias the results obtained in studies of organic N uptake using dual-labeled amino acids (15N, 13C). In a rhizosphere tube experiment we investigated 13C and 14C uptake by maize either supplied with labeled...

  13. Cyclosporine, a P-glycoprotein modulator, increases [{sup 18}F]MPPF uptake in rat brain and peripheral tissues: microPET and ex vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Lacan, Goran; Way, Baldwin M. [UCLA, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States); Plenevaux, Alain; Defraiteur, Caroline; Lemaire, Christian; Aerts, Joel; Luxen, Andre [Liege University, Cyclotron Research Center, Liege (Belgium); Rubins, Daniel J. [Merck and Co., Inc, Merck Research Laboratories, West Point, PA (United States); Cherry, Simon R. [Cyclotron Research Center, Department of Biomedical Engineering, Davis, CA (United States); Melega, William P. [UCLA, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States); UCLA School of Medicine, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States)

    2008-12-15

    Pretreatment with cyclosporine, a P-glycoprotein (P-gp) modulator increases brain uptake of 4-(2'-methoxyphenyl)-1-[2'-(N-2''-pyridinyl)-p-[{sup 18}F]fluorobenzamido]ethylpiperazine ([{sup 18}F]MPPF) for binding to hydroxytryptamine{sub 1A} (5-HT{sub 1A}) receptors. Those increases were quantified in rat brain with in vivo microPET and ex vivo tissue studies. Each Sprague-Dawley rat (n=4) received a baseline [{sup 18}F]MPPF microPET scan followed by second scan 2-3 weeks later that included cyclosporine pretreatment (50 mg/kg, i.p.). Maximum a posteriori reconstructed images and volumetric ROIs were used to generate dynamic radioactivity concentration measurements for hippocampus, striatum, and cerebellum, with simplified reference tissue method (SRTM) analysis. Western blots were used to semiquantify P-gp regional distribution in brain. MicroPET studies showed that hippocampus uptake of [{sup 18}F]MPPF was increased after cyclosporine; ex vivo studies showed similar increases in hippocampus and frontal cortex at 30 min, and for heart and kidney at 2.5 and 5 min, without concomitant increases in [{sup 18}F]MPPF plasma concentration. P-gp content in cerebellum was twofold higher than in hippocampus or frontal cortex. These studies confirm and extend prior ex vivo results (J. Passchier, et al., Eur J Pharmacol, 2000) that showed [{sup 18}F]MPPF as a substrate for P-gp. Our microPET results showed that P-gp modulation of [{sup 18}F]MPPF binding to 5-HT{sub 1A} receptors can be imaged in rat hippocampus. The heterogeneous brain distribution of P-gp appeared to invalidate the use of cerebellum as a nonspecific reference region for SRTM modeling. Regional quantitation of P-gp may be necessary for accurate PET assessment of 5-HT{sub 1A} receptor density when based on tracer uptake sensitive to P-gp modulation. (orig.)

  14. Effectiveness and acceptability of parental financial incentives and quasi-mandatory schemes for increasing uptake of vaccinations in preschool children: systematic review, qualitative study and discrete choice experiment.

    Science.gov (United States)

    Adams, Jean; Bateman, Belinda; Becker, Frauke; Cresswell, Tricia; Flynn, Darren; McNaughton, Rebekah; Oluboyede, Yemi; Robalino, Shannon; Ternent, Laura; Sood, Benjamin Gardner; Michie, Susan; Shucksmith, Janet; Sniehotta, Falko F; Wigham, Sarah

    2015-11-01

    Uptake of preschool vaccinations is less than optimal. Financial incentives and quasi-mandatory policies (restricting access to child care or educational settings to fully vaccinated children) have been used to increase uptake internationally, but not in the UK. To provide evidence on the effectiveness, acceptability and economic costs and consequences of parental financial incentives and quasi-mandatory schemes for increasing the uptake of preschool vaccinations. Systematic review, qualitative study and discrete choice experiment (DCE) with questionnaire. Community, health and education settings in England. Qualitative study - parents and carers of preschool children, health and educational professionals. DCE - parents and carers of preschool children identified as 'at high risk' and 'not at high risk' of incompletely vaccinating their children. Qualitative study - focus groups and individual interviews. DCE - online questionnaire. The review included studies exploring the effectiveness, acceptability or economic costs and consequences of interventions that offered contingent rewards or penalties with real material value for preschool vaccinations, or quasi-mandatory schemes that restricted access to 'universal' services, compared with usual care or no intervention. Electronic database, reference and citation searches were conducted. Systematic review - there was insufficient evidence to conclude that the interventions considered are effective. There was some evidence that the quasi-mandatory interventions were acceptable. There was insufficient evidence to draw conclusions on economic costs and consequences. Qualitative study - there was little appetite for parental financial incentives. Quasi-mandatory schemes were more acceptable. Optimising current services was consistently preferred to the interventions proposed. DCE and questionnaire - universal parental financial incentives were preferred to quasi-mandatory interventions, which were preferred to targeted

  15. Carboxylates and the uptake of ammonium by excised maize roots

    NARCIS (Netherlands)

    Breteler, H.

    1975-01-01

    The effect of carboxylates (organic acid anions) on NH 4 uptake was studied by changing the carboxylate level of roots prior to uptake experi ments. Succinate was the most effective stimulator of ammonium uptake. The oxocarboxylates (α-oxoglutarate, oxaloacetate and

  16. Determinants in the uptake of the human papillomavirus vaccine

    DEFF Research Database (Denmark)

    de Casadevante, Victoria Fernández; Cuesta, Julita Gil; Cantarero Arevalo, Lourdes

    2015-01-01

    of HPVV uptake in Europe. Methods: We performed a systematic Pubmed, Scopus, and Science Direct search to find articles published from HPVV availability in European countries until April 2014. No age restriction was applied. We included all studies assessing factors associated with HPVV uptake. Uptake...

  17. Structural Studies of Bacterioferritin B from Pseudomonas aeruginosa Suggest a Gating Mechanism for Iron Uptake via the Ferroxidase Center

    Energy Technology Data Exchange (ETDEWEB)

    Weeratunga, Saroja K.; Lovell, Scott; Yao, Huili; Battaile, Kevin P.; Fischer, Christopher J.; Gee, Casey E.; Rivera, Mario (Kansas); (HWMRI)

    2010-03-16

    solution, suggest that the ferroxidase pore is the dominant entry route for the uptake of iron by Pa BfrB. These findings, which are clearly distinct from those made with Escherichia coli Bfr [Crow, A. C., Lawson, T. L., Lewin, A., Moore, G. R., and Le Brun, N. E. (2009) J. Am. Chem. Soc. 131, 6808-6813], indicate that not all bacterioferritins operate in the same manner.

  18. Association between male partner involvement and the uptake of prevention of mother-to-child transmission of HIV (PMTCT interventions in Mwanza district, Malawi: a retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Fatch W Kalembo

    Full Text Available OBJECTIVE: The main objective of this study was to examine the association between male partner involvement and the uptake of prevention of mother-to-child transmission of HIV (PMTCT interventions. METHODS: A retrospective cohort study was used to collect data on women, their male partners and their children who were enrolled in a PMTCT program from January 2004 to December 2006 at Mwanza District Hospital. HIV infected women and their children were followed-up over the 18 months postnatal period. Data were analyzed using descriptive statistics, chi-square test and logistic regression. RESULTS: A total of 476 HIV positive women were enrolled in a PMTCT program and were followed-up in the study. Of those followed-up in the study, 65 (13.7% had a male partner involvement while 411 (86.3% had no male partner involvement. Male partner involvement was significantly associated with condom use (Adjusted odds ratio [AOR] = 5.6, 95% confidence interval [CI]: 2.3-13.5, P<0.001, hospital delivery (AOR = 25.9, 95%CI: 10.6-63.6, P<0.001, and completion of follow-up in the program (AOR = 16.8, 95% CI: 8.5-33.4, P<0.001. CONCLUSION: Male partner involvement increases the uptake of some PMTCT interventions by HIV positive women. Multi-strategic, culturally tailored public health care models are needed to increase the rate of male partner involvement in the program.

  19. Early uptake of HIV counselling and testing among pregnant women at different levels of health facilities – experiences from a community-based study in Northern Vietnam

    DEFF Research Database (Denmark)

    Nguyen Thi Thuy, Hanh; Gammeltoft, Tine; Rasch, Vibeke

    2011-01-01

    .0% of the women interviewed had attended antenatal care and 90.3% had been tested for HIV during their most recent pregnancy. Women who had their first antenatal checkup at primary health facilities were significantly more likely to be tested before 34 weeks of gestation (OR = 43.2, CI: 18.9-98.1). The reported......ABSTRACT: BACKGROUND: HIV counselling and testing for pregnant women is a key factor for successful prevention of mother to child transmission of HIV. Women's access to testing can be improved by scaling up the distribution of this service at all levels of health facilities. However, this strategy...... will only be effective if pregnant women are tested early and provided enough counselling. OBJECTIVE: To assess early uptake of HIV testing and the provision of HIV counselling among pregnant women who attend antenatal care at primary and higher level health facilities. METHODS: A community based study...

  20. Short-term study of the uptake of PrPSc by the Peyer’s patches in hamsters after oral exposure to scrapie

    DEFF Research Database (Denmark)

    Bergström, Ann-Louise; Jensen, Tim Kåre; Heegaard, Peter M. H.;

    2006-01-01

    The disease-associated prion protein (PrPSc) has been detected in the ileal Peyer's patches of lambs as early as one week after oral exposure to scrapie. In hamsters, the earliest reported time of PrPSc detection in the Peyer's patches after oral exposure to scrapie is 69 days post......-infection. To evaluate the acute uptake of inoculum and to investigate whether the Peyer's patches constitute the primary site of entry for scrapie after oral exposure, hamsters were each exposed orally to 1 ml of a 10% brain homogenate from hamsters in the terminal stage of infection with the 263 K strain...... of the scrapie agent. PrPSc was demonstrated in the Peyer's patches only a few days after exposure, i.e., much earlier than previously reported. This study Supports the view that the Peyer's patches constitute at least one of the primary entry sites of PrPSc after oral exposure to scrapie....

  1. Metal-contaminated resuspended sediment particles are a minor metal-uptake route for the Sydney rock oyster (Saccostrea glomerata)--A mesocosm study, Sydney Harbour estuary, Australia.

    Science.gov (United States)

    Lee, J-H; Birch, G F; Simpson, S L

    2016-03-15

    Resuspension of surficial sediments is considered a key process influencing bioaccumulation of metals in filter-feeders in the contaminated Sydney Harbour estuary (Australia). However, previous investigations were unable to establish a significant relationship between metals in sediments or suspended particulate matter (SPM) and oyster tissue concentrations. This study used a 60-d laboratory mesocosm experiment to expose Sydney rock oysters, Saccostrea glomerata, to a natural range of SPM concentrations with different SPM-metal concentrations. Dissolved metal concentrations were low and the availability of algae provided as food was constant for all treatments. Tissue metal concentrations of Cu, Pb and Zn increased significantly, however, no relationship was determined between tissue metal concentrations in the oyster and either SPM or SPM-metal concentrations. The results indicated that exposure to resuspended contaminated sediment particles contributed little to the observed metal uptake. Dissolved or algae food sources appear to be more important for metal accumulation in these oysters.

  2. Modeling the capture rate by a radially oscillating spherical bubble. A bio-mimetic model for studying the mechanically-mediated uptake by cells

    Science.gov (United States)

    Raudino, Antonio; Raciti, Domenica; Grassi, Antonio

    2016-11-01

    The surface of living cells constitutes a dynamic environment submitted to complex oscillatory motions. Oscillations may modify the uptake of incoming molecules. In this study we explored a bio-mimetic system formed by oscillating bubbles suspended in a sea of randomly distributed diffusants. We investigated by a time-dependent Fokker-Planck equation the effect of the periodic motions on the adsorption of a diffusant onto the moving bubble surface. We introduced both direct interactions between the diffusant and the fluctuating surface and indirect interactions due to the hydrodynamic motions around a vibrating surface. Results are expressed in terms of oscillation frequencies and amplitudes. An overall reduction of the bound diffusant at the bubble surface was observed.

  3. A Greenhouse Study on Lead Uptake and Antioxidant Enzyme Activities in Vetiver Grass (Vetiveria zizanioides) as a Function of Lead Concentration and Soil Physico-Chemical Properties

    Science.gov (United States)

    Andra, S. P.; Datta, R.; Sarkar, D.; Saminathan, S. K.

    2006-05-01

    Lead (Pb) is a toxic non-essential metal that can cause permanent learning disabilities, retardation, mental and behavioral problems in children. Lead accumulation in soils result from weathering, chipping, scraping, sanding and sand blasting of housing structures constructed prior to 1978, bearing lead-based paint. The primary objective of this study is to develop a cost-effective, chelate-assisted phytoremediation for cleaning up lead contaminated soils. Soils are a unique environment of diverse physical and chemical characteristics that influence the extent of phytoavailable (labile) Pb forms. The success of phytoremediation strategy depends on the physiological/ biochemical tolerance of the plants to lipid peroxidation induced by Pb at sub-lethal levels. Oxidative challenge is alleviated by antioxidant compounds, but more importantly by the induction of antioxidant enzymes, which are crucial for scavenging reactive oxygen species (ROS) and terminating lipid peroxidation chain reaction. A column study was conducted in a temperature and humidity-controlled greenhouse setting to assess the extent of Pb phytoextraction and antioxidant response in a lead accumulator, vetiver grass (Vetiveria zizanioides). Treatments consisted of a randomized block arrangement of 4 soil types (Immokalee, Pahokee Muck, Tobosa, and Millhopper) and 3 soil Pb concentrations [normal - 400 mg/kg lead (following federal soil standards for lead), moderate - 800 mg/kg lead, and excessive - 1200 mg/kg lead] in 4 replicates. At the end of 6 months, selected columns were amended with a biodegradable chelating agent, ethylenediamene disuccinate (10 mmol/ kg EDDS), to mobilize Pb and enhance Pb uptake by vetiver. Total and exchangeable (labile) Pb were correlated with phytoextracted Pb, and levels of antioxidant enzymes viz., superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the root and shoot tissues of vetiver grass. Results indicate that Pb uptake and antioxidant

  4. Studies of iron-uptake mechanisms in two bacterial species of the shewanella genus adapted to middle-range (Shewanella putrefaciens) or antarctic (Shewanella gelidimarina) temperatures.

    Science.gov (United States)

    Pakchung, Amalie A H; Soe, Cho Z; Codd, Rachel

    2008-10-01

    Iron(III)-uptake mechanisms in bacteria indigenous to the Antarctic, which is the most Fe-deficient continent on Earth, have not been extensively studied. The cold-adapted, Antarctic bacterium, Shewanella gelidimarina, does not produce detectable levels of the siderophore, putrebactin, in the supernatant of Fe(III)-deprived cultures. This is distinct from the putrebactin-producing bacterium from the same genus, Shewanella putrefaciens, which is adapted to middle-range temperatures. The production of putrebactin by S. putrefaciens is optimal, when the pH value of the medium is 7.0. According to the strong positive response from whole cells in the Chrome Azurol S (CAS) agar diffusion assay, Shewanella gelidimarina appears to produce cell-associated siderophores. In the RP-HPLC trace of an Fe(III)-loaded extract from the cell-associated components of S. gelidimarina cultured in media with [Fe(III)] ca. 0 microM, a peak appears at [MeCN] ca. 77%, which decreases in intensity in a parallel experiment in which [Fe(III)] ca. 5 microM, and is barely detectable in Fe(III)-replete media ([Fe(III)] ca. 20 microM). The Fe(III)-dependence of this peak suggests that the attendant species, which is significantly more hydrophobic than putrebactin (RP-HPLC elution: [MeCN] ca. 14%), is associated with Fe(III)-management in S. gelidimarina. This study highlights the diversity in Fe(III)-uptake mechanisms in Shewanella species adapted to different environmental and thermal niches.

  5. Whakawhanaungatanga: the importance of culturally meaningful connections to improve uptake of pulmonary rehabilitation by Māori with COPD – a qualitative study

    Directory of Open Access Journals (Sweden)

    Levack WMM

    2016-03-01

    Full Text Available William MM Levack, Bernadette Jones, Rebecca Grainger, Pauline Boland, Melanie Brown, Tristram R Ingham Department of Medicine, University of Otago, Wellington, New Zealand Background: Pulmonary rehabilitation is known to improve function and quality of life for people with chronic obstructive pulmonary disease (COPD. However, little research has been conducted on the influence of culture on experiences of pulmonary rehabilitation. This study examined factors influencing uptake of pulmonary rehabilitation by Māori with COPD in New Zealand. Method: Grounded theory nested within kaupapa Māori methodology. Transcripts were analyzed from interviews and focus groups with 15 Māori and ten New Zealand non-Māori invited to attend pulmonary rehabilitation for COPD. Māori participants had either attended a mainstream hospital-based program, a community-based program designed “by Māori, for Māori”, or had experienced both. Results: Several factors influencing uptake of pulmonary rehabilitation were common to all participants regardless of ethnicity: 1 participants’ past experiences (eg, of exercise; of health care systems, 2 attitudes and expectations, 3 access issues (eg, time, transport, and conflicting responsibilities, and 4 initial program experiences. These factors were moderated by the involvement of family and peers, interactions with health professionals, the way information on programs was presented, and by new illness events. For Māori, however, several additional factors were also identified relating to cultural experiences of pulmonary rehabilitation. In particular, Māori participants placed high value on whakawhanaungatanga: the making of culturally meaningful connections with others. Culturally appropriate communication and relationship building was deemed so important by some Māori participants that when it was absent, they felt strongly discouraged to attend pulmonary rehabilitation. Only the more holistic services

  6. A Study Protocol for the Australasian Oncofertility Registry: Monitoring Referral Patterns and the Uptake, Quality, and Complications of Fertility Preservation Strategies in Australia and New Zealand.

    Science.gov (United States)

    Anazodo, Antoinette C; Stern, Catharyn J; McLachlan, Robert I; Gerstl, Brigitte; Agresta, Franca; Cohn, Richard J; Jayasinghe, Yasmin; Wakefield, Claire E; Daly, Genevieve; Chan, Daisy; Gilbert, Lorrae; Kemertzis, Matthew; Orme, Lisa M; Wand, Handan; Viney, Rosalie; Gillam, Lynn; Deans, Rebecca; Jetti, Murali; Wu, John; Chapman, Michael; Ledger, William; Sullivan, Elizabeth A

    2016-09-01

    Improvements in cancer diagnosis and treatment in patients of a reproductive age have led to significant improvements in survival rates; however, a patient's fertility can be affected by both cancer and its treatment. As survival rates improve, there is an expectation by clinicians and patients that patient's reproductive potential should be considered and protected as much as possible. However, there is a lack of data about current fertility preservation (FP) uptake as well as accurate data on the acute or permanent reproductive risks of cancer treatment, complications of FP in cancer patients, and the use and success of assisted reproductive technology by cancer survivors. FP remains a major gap in acute cancer management with lifelong implications for cancer survivors. The FUTuRE Fertility research team has established the first binational multisite Australasian Oncofertility Registry, which is collecting a complete oncofertility data set from cancer and fertility centers in Australia and New Zealand. Outcomes from the research study will monitor referral, uptake, and complications of FP, document patient's reproductive potential after treatment, and collect data on the use of assisted reproductive technology following cancer treatment. The data will be linked to other routine health and administrative data sets to allow for other research projects to be carried out. The changes in oncofertility care will be benchmarked against the Australasian Oncofertility Charter. The data will be used to develop evidence-based guidelines and resources, including development of accurate risk projections for patients' risk of infertility, allowing clinicians to make recommendations for FP or assisted reproductive technology. Australian New Zealand Clinical Trials Number-12615000221550.

  7. Decision-making processes for the uptake and implementation of family-based therapy by eating disorder treatment teams: a qualitative study.

    Science.gov (United States)

    Kimber, Melissa; Couturier, Jennifer; Jack, Susan; Niccols, Alison; Van Blyderveen, Sherry; McVey, Gail

    2014-01-01

    To explore the decision-making processes involved in the uptake and implementation of evidence-based treatments (EBTs), namely, family-based treatment (FBT), among therapists and their administrators within publically funded eating disorder treatment programs in Ontario, Canada. Fundamental qualitative description guided sampling, data collection, and analytic decisions. Forty therapists and 11 administrators belonging to a network of clinicians treating eating disorders completed an in-depth interview regarding the decision-making processes involved in EBT uptake and implementation within their organizations. Content analysis and the constant comparative technique were used to analyze interview transcripts, with 20% of the data independently double-coded by a second coder. Therapists and their administrators identified the importance of an inclusive change culture in evidence-based practice (EBP) decision-making. Each group indicated reluctance to make EBP decisions in isolation from the other. Additionally, participants identified seven stages of decision-making involved in EBT adoption, beginning with exposure to the EBT model and ending with evaluating the impact of the EBT on patient outcomes. Support for a stage-based decision-making process was in participants' indication that the stages were needed to demonstrate that they considered the costs and benefits of making a practice change. Participants indicated that EBTs endorsed by the Provincial Network for Eating Disorders or the Academy for Eating Disorders would more likely be adopted. Future work should focus on integrating the important decision-making processes identified in this study with known implementation models to increase the use of low-cost and effective treatments, such as FBT, within eating disorder treatment programs. Copyright © 2013 Wiley Periodicals, Inc.

  8. Cohort study investigating the effects of first stage of the English tobacco point-of-sale display ban on awareness, susceptibility and smoking uptake among adolescents

    Science.gov (United States)

    Bogdanovica, Ilze; McNeill, Ann; Britton, John

    2017-01-01

    Objective A prospective evaluation of the effect of 2012 point-of-sale (PoS) display ban in supermarkets in England on perceived exposure to PoS displays, and on changes in susceptibility and smoking uptake among young people. Design Cohort study. Settings Seven schools in Nottinghamshire, England. Participants 1035 11–16-year-old school children. Primary and secondary outcome measures Changes in reported exposure to PoS displays before and after prohibition, and the association between exposure to and awareness of PoS displays and change in susceptibility to smoking and smoking status between 2011 and 2012 (before the ban) and 2012 and 2013 (after the ban). Results The proportion of children noticing tobacco PoS displays in supermarkets most or every time they visited a shop changed little between 2011 and 2012 (59.6% (95% CI 56.6% to 62.6%) and 58.8% (95% CI 55.8% to 61.8%), respectively); but decreased by about 13 percentage points to 45.7% (95% CI 42.7% to 48.7%) in 2013, after the ban. However, after adjusting for confounders, implementation of the first stage of the PoS ban in 2012 did not result in significant changes in the relation between susceptibility to smoking and smoking status and exposure to and awareness of PoS displays. Conclusions Prohibition of PoS in large supermarkets resulted in a decline in the proportion of young people noticing PoS displays in large shops, but little or no change in smoking uptake or susceptibility. It remains to be seen whether extension of the PoS ban to all shops in 2015 has a more marked effect. PMID:28115330

  9. Early uptake of HIV counseling and testing among pregnant women at different levels of health facilities - experiences from a community-based study in Northern Vietnam

    Directory of Open Access Journals (Sweden)

    Gammeltoft Tine

    2011-02-01

    Full Text Available Abstract Background HIV counselling and testing for pregnant women is a key factor for successful prevention of mother to child transmission of HIV. Women's access to testing can be improved by scaling up the distribution of this service at all levels of health facilities. However, this strategy will only be effective if pregnant women are tested early and provided enough counselling. Objective To assess early uptake of HIV testing and the provision of HIV counselling among pregnant women who attend antenatal care at primary and higher level health facilities. Methods A community based study was conducted among 1108 nursing mothers. Data was collected during interviews using a structured questionnaire focused on socio-economic background, reproductive history, experience with antenatal HIV counselling and testing as well as types of health facility providing the services. Results In all 91.0% of the women interviewed had attended antenatal care and 90.3% had been tested for HIV during their most recent pregnancy. Women who had their first antenatal checkup at primary health facilities were significantly more likely to be tested before 34 weeks of gestation (OR = 43.2, CI: 18.9-98.1. The reported HIV counselling provision was also higher at primary health facilities, where women in comparison with women attending higher level health facilities were nearly three or and four times more likely to receive pre-test (OR = 2.7; CI:2.1-3.5 and post-test counseling (OR = 4.0; CI: 2.3-6.8. Conclusions The results suggest that antenatal HIV counseling and testing can be scaled up to primary heath facilities and that such scaling up may enhance early uptake of testing and provision of counseling.

  10. 桃铁离子吸收动力学研究%Studies on Uptake Kinetics of Fe Ion for Peach (P. persica)

    Institute of Scientific and Technical Information of China (English)

    方从兵; 孙俊

    2001-01-01

    The influences of Fe ion status, pH and NaCl stress on Fe ion u p take characteristics were studied in peach (Prunus persica) seedlings with 35-da ys-old . The results showed that pH is the major factor of affecting iron ab sorption. Efficiency of different Fe ion status in peach was determined by p H. Fe ion uptake kinetic parameters Km and Imax were influenced by pH and F e ion status respectively. The findings also revealed the effect of NaCl str ess on Fe ion uptake characteristics of salt-sensitive plant (peach), which may be closely related to perviousness of plast membrane, activity of carrier system and free iron content respectively in cultivated medium.%以毛桃幼苗为试材,对不同铁形态、pH值和盐胁迫条件下铁离子吸收动力学 特性进行了研究。结果表明,pH是影响铁吸收的主要因素,不同铁形态的有效性随pH的变化 而变化;pH和铁形态影响桃铁离子吸收动力学参数Km和Imax;NaCl 胁迫对盐敏感性植物(桃 )铁吸收特性的影响,可能与质膜透性、载体系统活性以及介质中有效铁含量有关。

  11. Thyroid Scan and Uptake

    Medline Plus

    Full Text Available ... type your comment or suggestion into the following text box: Comment: E-mail: Area code: Phone no: Thank you! Images × Image Gallery Photograph of a typical probe counter used for thyroid uptake exams. The patient sits with the camera directed at the neck for five minutes, and then the leg for ...

  12. Radium uptake during barite recrystallization at 23 ± 2 °C as a function of solution composition: An experimental 133Ba and 226Ra tracer study

    Science.gov (United States)

    Curti, E.; Fujiwara, K.; Iijima, K.; Tits, J.; Cuesta, C.; Kitamura, A.; Glaus, M. A.; Müller, W.

    2010-06-01

    -2 d -1) were determined. Radium uptake by barite was determined by monitoring the decrease of 226Ra activity in the aqueous solution with alpha spectrometry, after filtration of the suspensions and sintering. The evaluation of the Ra uptake experiments, in conjunction with the recrystallization data, consistently indicated formation of non-ideal solid solutions, with moderately high Margules parameters ( WAB = 3720-6200 J/mol, a0 = 1.5-2.5). These parameters are significantly larger than an estimated value from the literature ( WAB = 1240 J/mol, a0 = 0.5). In conclusion, our results confirm that radium forms solid solutions with barite at fast kinetic rates and in complete thermodynamic equilibrium with the aqueous solutions. Moreover, this study provides quantitative thermodynamic data that can be used for the calculation of radium concentration limits in environmentally relevant systems, such as radioactive waste repositories and uranium mill tailings.

  13. Sequestration of Sr(II) by calcium oxalate—A batch uptake study and EXAFS analysis of model compounds and reaction products

    Science.gov (United States)

    Singer, David M.; Johnson, Stephen B.; Catalano, Jeffrey G.; Farges, François; Brown, Gordon E., Jr.

    2008-10-01

    Calcium oxalate monohydrate (CaC 2O 4·H 2O—abbreviated as CaOx) is produced by two-thirds of all plant families, comprising up to 80 wt.% of the plant tissue and found in many surface environments. It is unclear, however, how CaOx in plants and soils interacts with metal ions and possibly sequesters them. This study examines the speciation of Sr(II) aq following its reaction with CaOx. Batch uptake experiments were conducted over the pH range 4-10, with initial Sr solution concentrations, [Sr] aq, ranging from 1 × 10 -4 to 1 × 10 -3 M and ionic strengths ranging of 0.001-0.1 M, using NaCl as the background electrolyte. Experimental results indicate that Sr uptake is independent of pH and ionic strength over these ranges. After exposure of CaOx to Sr aq for two days, the solution Ca concentration, [Ca] aq, increased for all samples relative to the control CaOx suspension (with no Sr added). The amount of Sr aq removed from solution was nearly equal to the total [Ca] aq after exposure of CaOx to Sr. These results suggest that nearly 90% of the Sr is removed from solution to a solid phase as Ca is released into solution. We suggest that the other 10% is sequestered through surface adsorption on a solid phase, although we have no direct evidence for this. Extended X-ray absorption fine structure (EXAFS) spectroscopy was used to determine the molecular-level speciation of Sr in the reaction products. Deconvolutions of the Sr K-edge EXAFS spectra were performed to identify multi-electron excitation (MEE) features. MEE effects were found to give rise to low-frequency peaks in the Fourier transform before the first shell of oxygen atoms and do not affect EXAFS fitting results. Because of potential problems caused by asymmetric distributions of Sr-O distances when fitting Sr K-edge EXAFS data using the standard harmonic model, we also employed a cumulant expansion model and an asymmetric analytical model to account for anharmonic effects in the EXAFS data. For Sr

  14. Increasing the uptake of long-acting and permanent methods of family planning: A qualitative study with village midwives in East Java and Nusa Tenggara Barat Provinces, Indonesia.

    Science.gov (United States)

    Titaley, Christiana R; Wijayanti, Ratna U; Damayanti, Rita; Setiawan, Agus Dwi; Dadun; Dachlia, Dini; Siagian, Ferdinand; Suparno, Heru; Saputri, Dwi Astuti Yunita; Harlan, Sarah; Wahyuningrum, Yunita; Storey, Douglas

    2017-10-01

    midwives to improve LAPM use, including strengthening the counseling services, accompanying clients to higher health facilities to obtain LAPM services, and providing services for groups of clients. All village midwives emphasized the importance of strengthening collaboration among stakeholders to increase the uptake of LAPM services. as midwives are the main family planning providers in Indonesia, efforts to address their challenges is essential. Enabling a supportive policy environment, strengthening promotional activities, increasing the number of training programs designed for village midwives-in addition to enhancing inter-sectoral collaboration-are some recommendations to improve LAPM uptake in study areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Heterogeneous uptake of gaseous nitric acid on dolomite (CaMg(CO3)2) and calcite (CaCO3) particles: a Knudsen cell study using multiple, single, and fractional particle layers.

    Science.gov (United States)

    Johnson, Elizabeth R; Sciegienka, Joanna; Carlos-Cuellar, Sofia; Grassian, Vicki H

    2005-08-11

    In this study, the heterogeneous uptake of gaseous nitric acid on dolomite, CaMg(CO3)2, and calcite, CaCO3, particles under dry conditions at 296 K was investigated. A Knudsen cell reactor was used to measure heterogeneous uptake coefficients for these reactions. Several different experiments were performed including those on many, single, and fractional layers of particles. For experiments using multiple particle layers, the Knudsen cell data were modeled to take into account gas diffusion into the underlying layers of the sample. From this analysis, initial heterogeneous uptake coefficients, gamma(o,t), were determined to be (5 +/- 2) x 10(-4) and (2 +/- 1) x 10(-3), for dolomite and calcite, respectively, at a nitric acid concentration of 6.5 x 10(10) molecules cm(-3). For experiments that employed single or fractional particle layers, the initial heterogeneous uptake coefficient was analyzed using a recent method described in the literature. Values of the initial heterogeneous uptake coefficient using this analysis were in agreement with the above analysis and determined to be (7 +/- 4) x 10(-4) and (2 +/- 0.4) x 10(-3) for CaMg(CO3)2 and CaCO3, respectively. In addition, these results are compared to previous literature values.

  16. Improving prescribing practices with rapid diagnostic tests (RDTs): synthesis of 10 studies to explore reasons for variation in malaria RDT uptake and adherence

    Science.gov (United States)

    Leurent, Baptiste; Baiden, Frank; Baltzell, Kimberly; Björkman, Anders; Bruxvoort, Katia; Clarke, Siân; DiLiberto, Deborah; Elfving, Kristina; Goodman, Catherine; Hopkins, Heidi; Lal, Sham; Liverani, Marco; Magnussen, Pascal; Mårtensson, Andreas; Mbacham, Wilfred; Mbonye, Anthony; Onwujekwe, Obinna; Roth Allen, Denise; Shakely, Delér; Staedke, Sarah; Vestergaard, Lasse S; Whitty, Christopher J M; Wiseman, Virginia; Chandler, Clare I R

    2017-01-01

    Objectives The overuse of antimalarial drugs is widespread. Effective methods to improve prescribing practice remain unclear. We evaluated the impact of 10 interventions that introduced rapid diagnostic tests for malaria (mRDTs) on the use of tests and adherence to results in different contexts. Design A comparative case study approach, analysing variation in outcomes across different settings. Setting Studies from the ACT Consortium evaluating mRDTs with a range of supporting interventions in 6 malaria endemic countries. Providers were governmental or non-governmental healthcare workers, private retail sector workers or community volunteers. Each study arm in a distinct setting was considered a case. Participants 28 cases from 10 studies were included, representing 148 461 patients seeking care for suspected malaria. Interventions The interventions included different mRDT training packages, supervision, supplies and community sensitisation. Outcome measures Analysis explored variation in: (1) uptake of mRDTs (% febrile patients tested); (2) provider adherence to positive mRDTs (% Plasmodium falciparum positive prescribed/given Artemisinin Combination Treatment); (3) provider adherence to negative mRDTs (% P. falciparum negative not prescribed/given antimalarial). Results Outcomes varied widely across cases: 12–100% mRDT uptake; 44–98% adherence to positive mRDTs; 27–100% adherence to negative mRDTs. Providers appeared more motivated to perform well when mRDTs and intervention characteristics fitted with their own priorities. Goodness of fit of mRDTs with existing consultation and diagnostic practices appeared crucial to maximising the impact of mRDTs on care, as did prior familiarity with malaria testing; adequate human resources and supplies; possible alternative treatments for mRDT-negative patients; a more directive intervention approach and local preferences for ACTs. Conclusions Basic training and resources are essential but insufficient to maximise

  17. Uptake of AV-1451 in meningiomas.

    Science.gov (United States)

    Bruinsma, Tyler J; Johnson, Derek R; Fang, Ping; Senjem, Matthew; Josephs, Keith A; Whitwell, Jennifer L; Boeve, Bradley F; Pandey, Mukesh K; Kantarci, Kejal; Jones, David T; Vemuri, Prashanthi; Murray, Melissa; Graff-Radford, Jonathan; Schwarz, Christopher G; Knopman, David S; Petersen, Ronald C; Jack, Clifford R; Lowe, Val J

    2017-09-08

    AV-1451 is an imaging agent labeled with the positron-emitting radiolabel Fluorine-18. 18F-AV-1451 binds paired helical filament tau (PHF-tau), a pathology related to Alzheimer's disease. In our study of AV-1451 uptake in the brains of cognitively normal subjects, we noted a case of a meningioma with visually significant uptake of AV-1451. We initiated the present retrospective study to further examine cases of meningioma that underwent AV-1451 imaging. We searched the patient records of 650 patients who had undergone AV-1451 at our institution for the keyword "meningioma" to identify potential cases. PET/CT and MRI results were visually reviewed and semi-quantitative analysis of PET was performed. A paired student's t test was run between background and tumor standard uptake values. Fisher's exact test was used to examine the association between AV-1451 uptake and presence of calcifications on CT. We identified 12 cases of meningioma, 58% (7/12) of which demonstrated uptake greater than background using both visual analysis and tumor-to-normal cortex ratios (T/N + 1.90 ± 0.83). The paired student's t test revealed no statistically significant difference between background and tumor standard uptake values (p = 0.09); however, cases with a T/N ratio greater than one showed statistically higher uptake in tumor tissue (p = 0.01). A significant association was noted between AV-1451 uptake and presence of calcifications (p = 0.01). AV-1451 PET imaging should be reviewed concurrently with anatomic imaging to prevent misleading interpretations of PHF-tau distribution due to meningiomas.

  18. Quantification of FDG PET studies using standardised uptake values in multi-centre trials : effects of image reconstruction, resolution and ROI definition parameters

    NARCIS (Netherlands)

    Westerterp, Marinke; Pruim, Jan; Oyen, Wim; Hoekstra, Otto; Paans, Anne; Visser, Eric; van Lanschot, Jan; Sloof, Gerrit; Boellaard, Ronald

    2007-01-01

    Purpose: Standardised uptake values (SUVs) depend on acquisition, reconstruction and region of interest (ROI) parameters. SUV quantification in multicentre trials therefore requires standardisation of acquisition and analysis protocols. However, standardisation is difficult owing to the use of diffe

  19. Equity in human papilloma virus vaccination uptake? : sexual behaviour, knowledge and demographics in a cross-sectional study in (un)vaccinated girls in the Netherlands

    NARCIS (Netherlands)

    Mollers, Madelief; Lubbers, Karin; Spoelstra, Symen K; Weijmar Schultz, Willibrordus; Daemen, Toos; Westra, Tjalke A; van der Sande, Marianne A B; Nijman, Hans W; de Melker, Hester E; Tami, Adriana

    2014-01-01

    Background: In the Netherlands, human papillomavirus (HPV) vaccination is part of a national program equally accessible for all girls invited for vaccination. To assess possible inequalities in vaccine uptake, we investigated differences between vaccinated and unvaccinated girls with regard to

  20. False-positive F-18 FDG uptake in PET/CT studies in pediatric patients with abdominal Burkitt's lymphoma.

    Science.gov (United States)

    Riad, Raef; Omar, Walid; Sidhom, Iman; Zamzam, Manal; Zaky, Iman; Hafez, Magdy; Abdel-Dayem, Hussein M

    2010-03-01

    In pediatric patients with abdominal Burkitt's lymphoma, the involvement of the gastrointestinal tract and abdominal lymph nodes are the main presenting feature of the disease. Chemotherapy is the main treatment modality and could be preceded by surgical excision of the abdominal masses. To achieve cure or long-term disease-free survival a balance has to be struck between aggressive chemotherapy and the probability of tumor necrosis secondary to treatment complicated by acute infections, perforation or intestinal bleeding. F-18 fluorodeoxyglucose-positron emission tomography/computed tomography (F-18 FDG-PET/CT) has been recommended over conventional imaging modalities for the follow-up of these patients and for monitoring treatment response. As the incidences of postchemotherapy complications are high, the positive predictive value of PET/CT studies in these patients is very low and the false-positive rate is high from acute infections and tumor necrosis. Accordingly, histopathological confirmation of positive lesions on F-18 FDG-PET/CT studies is essential. This is especially important as post-therapy complications might present with nonspecific and nonurgent symptoms. At the same time initiating a second course of salvage chemotherapy is risky. Retrospectively reviewed F-18 FDG-PET/CT studies for 28 pediatric patients with abdominal Burkitt's lymphoma and diffuse large B-cell lymphoma after their treatment with chemotherapy or surgery. Four positive studies were found. All had pathological verification and were because of acute inflammation and tumor necrosis and there was no evidence of viable tumor cells. One patient had multiple recurrent lesions in the abdomen after the initial surgical excision and before starting chemotherapy. The incidence of acute complications in this series is 10.7%. This study confirms the high incidence of tumor necrosis and inflammation after chemotherapy for the abdominal Burkitt's lymphoma and consequently, the incidence of true

  1. Cutoff value of thyroid uptake of (99m)Tc-pertechnetate to discriminate between Graves' disease and painless thyroiditis: a single center retrospective study.

    Science.gov (United States)

    Uchida, Toyoyoshi; Suzuki, Ruriko; Kasai, Takatoshi; Onose, Hiroyuki; Komiya, Koji; Goto, Hiromasa; Takeno, Kageumi; Ishii, Shinya; Sato, Junko; Honda, Akira; Kawano, Yui; Himuro, Miwa; Yamada, Emiko; Yamada, Tetsu; Watada, Hirotaka

    2016-01-01

    Thyroid uptake of (99m)Tc-pertechnetate is a useful way to determine the cause of thyrotoxicosis. In daily clinical practice, (99m)Tc-pertechnetate uptake is used to discriminate between Graves' disease and painless thyroiditis when clinical information is not enough to make the distinction. However, since the optimal cutoff value of (99m)Tc-pertechnetate uptake has not yet been elucidated, our aim was to determine this value. We recruited patients with thyrotoxicosis in whom (99m)Tc-pertechnetate uptake was measured in clinical settings between 2009 and 2013. Three experienced endocrinologists (who were blinded to the value of (99m)Tc-pertechnetate uptake and initial treatment) diagnosed the cause of thyrotoxicosis based on thyrotropin, free triiodothyronine, free thyroxine, and thyrotropin receptor antibody levels, and by ultrasound findings and using images of thyroid uptake of (99m)Tc-pertechnetate without the actual values. Ninety-four patients diagnosed as having Graves' disease or painless thyroiditis were finally included. According to the diagnosis, the optimal cutoff value of (99m)Tc-pertechnetate uptake was determined by receiver operating characteristics analysis. A cutoff value of 1.0% provided optimal sensitivity and specificity of 96.6% and 97.1%, respectively. Then, its validity was confirmed in 78 patients with confirmed Graves' disease or painless thyroiditis diagnosed at another institute. Applying this cutoff value to the patients with thyrotoxicosis revealed positive and negative predictive values for Graves' disease of 100% and 88.9%, respectively. In conclusion, a cutoff value for (99m)Tc-pertechnetate uptake of 1.0% was useful to discriminate between Graves' disease and painless thyroiditis.

  2. Striatal FDOPA uptake and cognition in advanced non-demented Parkinson's disease : A clinical and FDOPA-PET study

    NARCIS (Netherlands)

    van Beilen, Marije; Portman, Axel T.; Kiers, Henk A. L.; Maguire, Ralph P.; Kaasinen, Valtteri; Koning, Marthe; Pruim, Jan; Leenders, Klaus L.

    2008-01-01

    This study sought to determine the nature of the relationship between cognition and striatal dopaminergic functioning in 28 patients with advanced Parkinson's disease (PD) using fluorodopa Positron emission tomography (FDOPA-PET) and neuropsychological test scores. Mental flexibility was related to

  3. Uptake of systematic reviews and meta-analyses based on individual participant data in clinical practice guidelines: descriptive study

    NARCIS (Netherlands)

    Vale, C.L.; Rydzewska, L.H.; Rovers, M.M.; Emberson, J.R.; Gueyffier, F.; Stewart, L.A.

    2015-01-01

    OBJECTIVE: To establish the extent to which systematic reviews and meta-analyses of individual participant data (IPD) are being used to inform the recommendations included in published clinical guidelines. DESIGN: Descriptive study. SETTING: Database maintained by the Cochrane IPD Meta-analysis Meth

  4. 渤海湾浮游生物氮吸收动力学研究%Study on nitrogen uptake of microplankton in the Bohai bay

    Institute of Scientific and Technical Information of China (English)

    李清雪

    2001-01-01

    Using 15N -labeled compounds, nitrogen uptake kinetics parameters of microplankton were measured during the two cruise of 18, August and 25, October in the Bohai Bay. The results showed nitrogen uptake kinetics of microplankton in the Bohai Bay agrees with Michaelis-Menten equation. The seasonal variation of nitrogen uptake of microplankton was higher in August than in October. The differences were obvious between ammonium uptake and nitrate uptake of microplankton. Nitrate uptake of microplankton were prone to be affected by temperature.%本文利用15N同位素示踪法,对渤海湾2个季节浮游生物氮吸收动力学进行了初步研究.结果表明,海洋浮游生物对氮营养盐的吸收动力学特性可由米门公式很好的描述.浮游生物对氮营养盐的吸收存在明显的季节变化,呈现夏季高,秋季低的特点,并且另外浮游生物对两种主要氮源&氨氮和硝酸盐氮的吸收存在明显的差异,浮游生物对硝酸盐比对氨氮吸收动力学参数的季节性变化较大.

  5. Do you use social media? A study into new nursing and midwifery graduates' uptake of social media.

    Science.gov (United States)

    Tuckett, Anthony; Turner, Catherine

    2016-04-01

    Social media use is expanding rapidly, so too is its use within hospitals and amongst healthcare professionals. This study describes the use of social media by Australian and New Zealand nursing and midwifery graduates of the Graduate e-Cohort study; there were 112 (93%) respondents from a 2014 sample of 121 nurses and midwives. Findings suggest that the professional peak body goal of using social media as a vehicle for professional education requires consideration of the social media platforms that are actually being used by new graduates. We recommend that work by the respective professions at both an undergraduate and graduate level needs to focus on the implications of social media use or policy and practice to ensure that everyone is aware of when and how to engage in social media platforms and what to do and how to behave when using social media.

  6. Adherence and uptake of artemisinin-based combination treatments for uncomplicated malaria: a qualitative study in northern Ghana.

    Directory of Open Access Journals (Sweden)

    Samuel Chatio

    Full Text Available Based on the recommendations of the World Health Organization in 2004, Ghana changed her antimalarial drug policy from mono-therapy to Artemisinin-based Combination Therapy (ACTs. The country is currently using three first line drugs artesunate-amodiaquine, artemether-lumefantrine and dihydroartemisinin-piperaquine for the treatment of uncomplicated malaria. Despite this policy, little or no qualitative studies have been conducted to establish the factors influencing adherence to the new treatment for malaria. This study explored factors influencing adherence to the use of ACTs in northern Ghana.This was a qualitative study comprising forty (40 in-depth interviews with patients with malaria who visited selected public and private health facilities and received ACTs. Systematic sampling technique was used to select participants who were given ACTs for the interviews. Nvivo 9 software was used to code the data into themes for further analysis.The study revealed very important differences in knowledge about ACTs. As expected, the less or illiterates could not mention the type of ACT they would prefer to use for treating their malaria. The educated ones had a good knowledge on ACTs and preferred artemether-lumefantrinee in treating their malaria. The reason was that the drug was good and it had minimal or no side effects. Individual attitudes toward the use of medications and the side effects associated with the use of these ACTs were found to be the main factors affecting adherence to the use of ACTs. Perceived cure of illness after the initial dose greatly affected adherence. Other factors such as forgetfulness and lack of information also influenced patient adherence to ACTs use.Individual knowledge, attitudes and behaviors greatly influence patients' adherence to ACTs use. Since ACTs take a number of days to complete, continuous education by health professionals could improve on adherence to ACTs use by patients with malaria.

  7. Energy-dispersive X-ray fluorescence study of elemental uptake in cauliflower

    Indian Academy of Sciences (India)

    D Gupta; J M Chatterjee; R Ghose; A K Mitra; S Roy; M Sarkar

    2011-02-01

    A109Cd radioisotope-induced energy-dispersive X-ray fluorescence (EDXRF) study has been performed on samples of cauliflower consisting of the flower, the leaves and the associated root soil. The cauliflowers were collected from farms near the main dumping site of municipal solid waste in the city of Kolkata, India and also from uncontaminated farms about 50 km away from the city. A unified calibration approach was undertaken for the elemental analysis of the samples of widely varying matrices. The present study suggests that the elemental concentrations in the root soils and leaves of the samples vary from farm to farm, whereby the concentrations of Cu, Zn and Pb in root soils of MSW-contaminated farms are higher by almost an order of magnitude compared to uncontaminated farms. But, the most notable feature of this study is the strikingly similar elemental concentrations in the edible flower part of all samples irrespective of the type of soil.

  8. Analysis of the Reasons for Non-Uptake of Predictive Testing for Huntington's Disease in Spain: A Qualitative Study.

    Science.gov (United States)

    Rivera-Navarro, Jesús; Cubo, Esther; Mariscal, Natividad

    2015-12-01

    Children of persons affected by Huntington's disease (HD) have a 50% chance of inheriting the disease. Genetic testing in Spain is offered to individuals (presymptomatic test) or mothers of fetuses (prenatal) who run the risk of suffering from HD. The objective of this study is to analyze the factors that influence the decisions of adult children of persons affected with HD regarding predictive testing. A qualitative research methodology was used involving 4 focus groups (FGs) made up of adult children of persons with HD in different cities in Spain. The results of the study showed that over half of the focus group participants were inclined to decline genetic testing. The main explanatory determinants for taking or not taking the predictive test are: Maturity of the individual at risk, which was directly related to age; Ability to cope with a positive test result; Experience of living with HD sufferers; Information about testing and psychological support; Attitude of the family; Social visibility of genetic testing; Personality and temperament of each subject at risk of HD. These results imply that these factors should be analyzed in more detail in quantitative studies in order to help the Spanish Department of Health understand why some children of parents with HD decline genetic testing, so that they may and apply these data when creating specific policy regarding this issue.

  9. Platinum uptake from chloride solutions using biosorbents

    Directory of Open Access Journals (Sweden)

    Mehmet Hakan Morcali

    2013-04-01

    Full Text Available Present work investigates platinum uptake from synthetically prepared, dilute platinum-bearing solutions using biomass residues, i.e. pistachio nut shell and rice husk, which are abundant in Turkey, and provides a comparison between these two biosorbents. Effects of the different uptake parameters, sorbent dosage, contact time, temperature and pH of solution on platinum uptake (% were studied in detail on a batch sorption. Before the pistachio nut shell was activated, platinum uptake (% was poor compared to the rice husk. However, after the pistachio nut shell was activated at 1000 °C under an argon atmosphere, the platinum uptake (% increased two-fold. The pistachio nut shell (original and activated and rice husk were shown to be better than commercially available activated carbon in terms of adsorption capacity. These two sorbents have also been characterized by FTIR and SEM. Adsorption equilibrium data best complied with the Langmuir isotherm model. Maximum adsorption capacities, Qmax, at 25 °C were found to be 38.31 and 42.02 mg.g- 1for the activated pistachio nut shell and rice husk, respectively. Thermodynamic calculations using the measured ∆H°, ∆S° and ∆G° values indicate that the uptake process was spontaneous and endothermic. The experimental data were shown to be fit the pseudo-second-order kinetic model.

  10. Uptake, outcomes, and costs of implementing non-invasive prenatal testing for Down’s syndrome into NHS maternity care: prospective cohort study in eight diverse maternity units

    Science.gov (United States)

    Wright, David; Hill, Melissa; Verhoef, Talitha I; Daley, Rebecca; Lewis, Celine; Mason, Sarah; McKay, Fiona; Jenkins, Lucy; Howarth, Abigail; Cameron, Louise; McEwan, Alec; Fisher, Jane; Kroese, Mark; Morris, Stephen

    2016-01-01

    Objective To investigate the benefits and costs of implementing non-invasive prenatal testing (NIPT) for Down’s syndrome into the NHS maternity care pathway. Design Prospective cohort study. Setting Eight maternity units across the United Kingdom between 1 November 2013 and 28 February 2015. Participants All pregnant women with a current Down’s syndrome risk on screening of at least 1/1000. Main outcome measures Outcomes were uptake of NIPT, number of cases of Down’s syndrome detected, invasive tests performed, and miscarriages avoided. Pregnancy outcomes and costs associated with implementation of NIPT, compared with current screening, were determined using study data on NIPT uptake and invasive testing in combination with national datasets. Results NIPT was prospectively offered to 3175 pregnant women. In 934 women with a Down’s syndrome risk greater than 1/150, 695 (74.4%) chose NIPT, 166 (17.8%) chose invasive testing, and 73 (7.8%) declined further testing. Of 2241 women with risks between 1/151 and 1/1000, 1799 (80.3%) chose NIPT. Of 71 pregnancies with a confirmed diagnosis of Down’s syndrome, 13/42 (31%) with the diagnosis after NIPT and 2/29 (7%) after direct invasive testing continued, resulting in 12 live births. In an annual screening population of 698 500, offering NIPT as a contingent test to women with a Down’s syndrome screening risk of at least 1/150 would increase detection by 195 (95% uncertainty interval −34 to 480) cases with 3368 (2279 to 4027) fewer invasive tests and 17 (7 to 30) fewer procedure related miscarriages, for a non-significant difference in total costs (£−46 000, £−1 802 000 to £2 661 000). The marginal cost of NIPT testing strategies versus current screening is very sensitive to NIPT costs; at a screening threshold of 1/150, NIPT would be cheaper than current screening if it cost less than £256. Lowering the risk threshold increases the number of Down’s syndrome cases detected and

  11. A Comparative Study on the Uptake and Toxicity of Nickel Added in the Form of Different Salts to Maize Seedlings

    Directory of Open Access Journals (Sweden)

    Jing Nie

    2015-11-01

    Full Text Available In soil ecotoxicological studies, a toxic metal is usually added in the form of either an inorganic or organic salt with relatively high solubility. Nitrate, chloride, acetate, or sulfate are commonly considered as valid options for that aim. However, recent studies have shown that different salts of the same metal at the same cationic concentration may exhibit different toxicities to plants and soil organisms. This information should be considered when selecting data to use for developing toxicological criteria for soil environment. A comparative study was carried out to evaluate the toxicity of five nickel (Ni salts: NiCl2, NiSO4, Ni(II-citrate, Ni(CH3COO2, and Ni(II-EDTA (ethylenediaminetetraacetate, on maize seedlings. The plant metrics used were plant height, shoot and root biomass, leaf soluble sugars and starch, and the Ni contents of the shoots and roots. The results indicated that when Ni was added to the soil, toxicity varied with the selected anionic partner with the following toxicity ranking NiSO4 < Ni(CH3COO2 < Ni(II-citrate < NiCl2 < Ni(II-EDTA. Taking the plant-height metric as an example, the effective concentrations for 50% inhibition (EC50 were 3148 mg·kg−1 for NiSO4, 1315 mg·kg−1 for NiCl2, and 89 mg·kg−1 for Ni(II-EDTA. Compared with the Ni in the other salts, that in Ni(II-EDTA was taken up the most efficiently by the maize roots and, thus, resulted in the greatest toxic effects on the plants. Nickel generally reduced leaf soluble sugars, which indicated an effect on plant carbohydrate metabolism. The outcome of the study demonstrates that different salts of the same metal have quite different ecotoxicities. Therefore, the anionic counterpart of a potentially toxic metal cation must be taken into account in the development of ecotoxicological criteria for evaluating the soil environment, and a preferred approach of leaching soil to reduce the anionic partner should also be considered.

  12. Uptake of radiolabeled morphiceptin and its analogs by experimental mammary adenocarcinoma: in vitro and in vivo studies

    Energy Technology Data Exchange (ETDEWEB)

    Mirowski, M. E-mail: mirowski@ich.pharm.am.lodz.pl; Wiercioch, R.; Janecka, A.; Balcerczak, E.; Byszewska, E.; Birnbaum, G.; Byzia, Sz.; Garnuszek, P.; Wierzbicki, R

    2004-05-01

    Morphiceptin (Tyr-Pro-Phe-Pro-NH{sub 2}) and its analogs modified at position 3: [D-Phe{sup 3}]morphiceptin, [D-ClPhe{sup 3}]morphiceptin and [D-Cl{sub 2}Phe{sup 3}]morphiceptin were synthesized and labeled with [{sup 125}I] or [{sup 131}I]. Their binding to membranes isolated from experimental adenocarcinoma was examined in vitro with the use of a cross-linking assay followed by the Western blot technique. The radioactive complex had molecular weight of about 65 kDa and was detectable by anti-{mu}-opioid receptor polyclonal antibody. Expression of the {mu}-opioid receptor in mouse mammary adenocarcinoma was confirmed by reverse transcriptase-polymerase chain reaction. The binding studies showed the highest affinity and capacity for [D-Phe{sup 3}]morphiceptin (K{sub d} 0.39 and B{sub max} 1112) and [D-ClPhe{sup 3}]morphiceptin (K{sub d} 1.8 and B{sub max} 220). Morphiceptin and its D-Cl{sub 2}Phe analog had significantly lower B{sub max} values (131 and 83, respectively). Biodistribution experiments in tumor-bearing C3H/Bi mice with the use of the {sup 131}I-labeled peptides confirmed the results of our in vitro studies. The highest accumulation of radioactive peptides in the tumor tissue was also found for peptides with D-Phe and D-ClPhe.

  13. Heavy Metals Uptake by Asian Swamp Eel, Monopterus albus from Paddy Fields of Kelantan, Peninsular Malaysia: Preliminary Study.

    Science.gov (United States)

    Yin, Sow Ai; Ismail, Ahmad; Zulkifli, Syaizwan Zahmir

    2012-12-01

    Swamp eel, Monopterus albus is one of the common fish in paddy fields, thus it is suitable to be a bio-monitor for heavy metals pollution studies in paddy fields. This study was conducted to assess heavy metals levels in swamp eels collected from paddy fields in Kelantan, Malaysia. The results showed zinc [Zn (86.40 μg/g dry weight)] was the highest accumulated metal in the kidney, liver, bone, gill, muscle and skin. Among the selected organs, gill had the highest concentrations of lead (Pb), cadmium (Cd) and nickel (Ni) whereas muscle showed the lowest total metal accumulation of Zn, Pb, copper (Cu), Cd and Ni. Based on the Malaysian Food Regulation, the levels of Zn and Cu in edible parts (muscle and skin) were within the safety limits. However, Cd, Pb and Ni exceeded the permissible limits. By comparing with the maximum level intake (MLI), Pb, Ni and Cd in edible parts can still be consumed. This investigation indicated that M. albus from paddy fields of Kelantan are safe for human consumption with little precaution.

  14. DNA binding, antioxidant, cytotoxicity (MTT, lactate dehydrogenase, NO), and cellular uptake studies of structurally different nickel(II) thiosemicarbazone complexes: synthesis, spectroscopy, electrochemistry, and X-ray crystallography.

    Science.gov (United States)

    Prabhakaran, R; Kalaivani, P; Huang, R; Poornima, P; Vijaya Padma, V; Dallemer, F; Natarajan, K

    2013-02-01

    Three new nickel(II) thiosemicarbazone complexes have been synthesized and characterized by analytical, spectral, and single-crystal X-ray diffraction studies. In complex 1, the ligand 2-hydroxy-1-naphthaldehydethiosemicarbazone coordinated as a monobasic tridentate donor, whereas in complexes 2 and 3, the ligands salicylaldehyde-4(N)-ethylthiosemicarbazone and 2-hydroxy-1-naphthaldehyde-4(N)-ethylthiosemicarbazone coordinated as a dibasic tridentate donor. The DNA binding ability of the complexes in calf thymus DNA was explored by absorption and emission titration experiments. The antioxidant property of the new complexes was evaluated to test their free-radical scavenging ability. In vitro cytotoxicity assays were performed for the new complexes in A549 and HepG2 cell lines. The new compounds overcome cisplatin resistance in the A549 cell line and they were also active in the HepG2 cell line. The cellular uptake study showed the accumulation of the complexes in tumor cells depended on the nature of the ligand attached to the nickel ion.

  15. [A phantom study for the evaluation of the effect of the high uptake in the liver on technetium-99m myocardial perfusion SPECT images].

    Science.gov (United States)

    Ohnishi, H; Masuda, K; Takada, M; Yamamoto, I; Morita, R

    1998-07-01

    The purpose of this study was to evaluate influences of the high hepatic uptake on parameters such as filtering, attenuation coefficient, and scatter correction at reconstructing of the myocardial SPECT images. Hepatic and cardiac spaces of a myocardial phantom (RH-2, Kyoto Kagaku), were filled with technetium-99m and a three-detector SPECT system (GCA 9300-DI, TOSHIBA) was used. The hepatic activity's influence was estimated from a qualitative percent regional scattering and the effects of attenuation and scatter correction were evaluated by a circumferential profile curve. Percent regional scattering increased in reverse to hepato-cardiac distance (HCD) and in proportion to hepatic to cardiac activity ratio (HCR). This tendency was observed the most significantly in the inferior region, followed by in the lateral, anterior and septal regions, declining in this order. An artifactual defect adjacent to the liver was observed when HCR is three and HCD is zero. However, when the Butterworth filter was used with small filtering-sizes and lower orders in combination with attenuation and scatter correction, the defects were decreased up to 15% at counts in the inferior region. This study showed that the hepatic to cardiac activity ratio, and the hepatocardiac distance should be considered for reconstruction of the SPECT images.

  16. A phantom study for the evaluation of the effect of the high uptake in the liver on technetium-99m myocardial perfusion SPECT images

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Hideo; Masuda, Kazutaka; Takada, Masahiko; Yamamoto, Itsuo; Morita, Rikushi [Shiga Univ., Otsu (Japan). Hospital

    1998-07-01

    The purpose of this study was to evaluate influences of the high hepatic uptake on parameters such as filtering, attenuation coefficient, and scatter correction at reconstructing of the myocardial SPECT images. Hepatic and cardiac spaces of a myocardial phantom (RH-2, Kyoto Kagaku), were filled with technetium-99m and a three-detector SPECT system (GCA 9300-DI, TOSHIBA) was used. The hepatic activity`s influence was estimated from a qualitative percent regional scattering and the effects of attenuation and scatter correction were evaluated by a circumferential profile curve. Percent regional scattering increased in reverse to hepato-cardiac distance (HCD) and in proportion to hepatic to cardiac activity ratio (HCR). This tendency was observed the most significantly in the inferior region, followed by in the lateral, anterior and septal regions, declining in this order. An artifactual defect adjacent to the liver was observed when HCR is three and HCD is zero. However, when the Butterworth filter was used with small filtering-sizes and lower orders in combination with attenuation and scatter correction, the defects were decreased up to 15% at counts in the inferior region. This study showed that the hepatic to cardiac activity ratio, and the hepato-cardiac distance should be considered for reconstruction of the SPECT images. (author)

  17. A study on thallium-201 SPECT in brain metastases of lung cancer. With special reference to tumor size and tumor to normal brain thallium uptake ratio

    Energy Technology Data Exchange (ETDEWEB)

    Togawa, Takashi; Yui, Nobuharu; Kinoshita, Fujimi; Yanagisawa, Masamichi; Namba, Hiroki [Chiba Cancer Center (Japan). Hospital

    1995-03-01

    Thallium-201 brain SPECT was performed on 20 patients with brain metastases of lung cancer using a three-head rotating gamma camera and the effect of tumor size on tumor detectability and tumor to normal brain thallium uptake ratio (T/N ratio) was studied. Among 71 metastatic lesions, only 9 (22.5%) of 40 lesions of 13 mm diameter or below and 31 (100%) of 31 lesions of 14 mm diameter or above could be detected in this study. There was significant correlation between T/N ratio and tumor size (r=0.75, p<0.001). The greater the metastatic lesion, the higher the T/N ratio. Even among the tumors in a single patient with multiple brain metastases, there was a significant linear correlation between tumor size and T/N ratio (r=0.96, p<0.01). In this patient, T/N ratio varied by the tumor size and these differences in T/N ratios were thought to be based on the partial volume effect. However, T/N{center_dot}d which was a parameter corrected by tumor diameter (d) showed a constant value regardless of tumor size. The present results showed that T/N ratio, which was usually believed to quantitate the malignancy grade of brain tumor, was affected by tumor size and that more accurate parameter could be obtained by the correction of T/N ratio by tumor size. (author).

  18. Copper and cadmium tolerance, uptake and effect on chloroplast ultrastructure. Studies on Salix purpurea and Phragmites australis

    Energy Technology Data Exchange (ETDEWEB)

    Hakmaoui, A.; Ater, A. [Abdelmalek Essaadi Univ., Tetouan (Morocco). Dept. of Biology; Boka, K. [Eoetvoes Lorand Univ., Budapest (Hungary). Dept. of Plant Anatomy; Baron, M. [Granada Univ. (Spain). Dept. of Biochemistry and Cell and Molecular Biology of Plants

    2007-05-15

    We have compared the effect of toxic Cu and Cd concentrations on growth, metal accumulation, and chloroplast ultrastructure of willow (Salix purpurea L.) and reed [Phragmites australis (Cav.) Trin. ex Steud.]. After a 10-day treatment, both species have tolerated to some extent the lowest concentration of both metals; however, plant growth was strongly reduced at the highest Cu and Cd concentrations. These plants could be described as Cu-tolerant at the lowest concentration tested, showing a higher tolerance index in reed than in willow; in contrast, willow exhibited higher tolerance against Cd. Both plants appeared to be moderate root accumulators of Cu and Cd. Ultrastructural studies revealed special features that can provide some protection against heavy metals stress, such as ferritin aggregates in the stroma. In addition, Cu and Cd induced distortion of thylakoids, reduction of grana stacks, as well as an increased number and size of plastoglobuli and peripheral vesicles. (orig.)

  19. Capillary electrophoresis with laser-induced fluorescence detection for studying amino acid uptake by yeast during beer fermentation.

    Science.gov (United States)

    Turkia, Heidi; Sirén, Heli; Penttilä, Merja; Pitkänen, Juha-Pekka

    2015-01-01

    The amino acid composition of cultivation broth is known to affect the biomass accumulation, productivity, and vitality of yeast during cultivation. A separation method based on capillary electrophoresis with laser-induced fluorescence (LIF) detection was developed for the determination of amino acid consumption by Saccharomyces cerevisiae during beer fermentation. Intraday relative standard deviations were less than 2.1% for migration times and between 2.9% and 9.9% for peak areas. Interday relative standard deviations were less than 2.5% for migration times and between 4.4% and 18.9% for peak areas. The quantification limit was even as low as 62.5 pM which equals to below attomole level detection. The method was applied to study the rate of amino acid utilization during beer fermentation.

  20. EVITEACH: a study exploring ways to optimise the uptake of evidence-based practice to undergraduate nurses.

    Science.gov (United States)

    Hickman, Louise D; Kelly, Helen; Phillips, Jane L

    2014-11-01

    EVITEACH aimed to increase undergraduate nursing student's engagement with evidence-based practice and enhance their knowledge utilisation and translation capabilities. Building students capabilities to apply evidence in professional practice is a fundamental university role. Undergraduate nursing students need to actively engage with knowledge utilisation and translational skill development to narrow the evidence practice gap in the clinical setting. A two phase mixed methods study was undertaken over a three year period (2008-2010, inclusive) utilizing a Plan-Do-Study-Act (PDSA) approach. Three undergraduate nursing cohorts (N = 188) enrolled in a compulsory knowledge translation and utilisation subject at one Australian university participated. Data collection comprised of subject evaluation data and reflective statements. Preliminary investigations identified priority areas related to subject: materials, resources, teaching and workload. These priority areas became the focus of action for two PDSA cycles. PDSA cycle 1 demonstrated significant improvement of the subject overall (p > 0.05), evaluation of the materials used (p > 0.001) and teaching sub-groups (p > 0.05). PDSA cycle 2 continued to sustain improvement of the subject overall (p > 0.05). Furthermore reflective statements collected during PDSA cycle 2 identified four themes: (1) What engages undergraduate nurses in the learning process; (2) The undergraduate nurses learning trajectory; (3) Undergraduate nurses' preconceptions of research and evidenced-based practice; and (4) Appreciating the importance of research and evidence-based practice to nursing. There is little robust evidence to guide the most effective way to build knowledge utilisation and translational skills. Effectively engaging undergraduate nursing students in knowledge translation and utilisation subjects could have immediate and long term benefits for nursing as a profession and patient outcomes. Developing evidence-based practice

  1. The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections--a pharmacokinetic study.

    Science.gov (United States)

    Hsu, Chao-Chin; Kuo, Hsin-Chih; Hsu, Chao-Tien; Gu, Qing

    2009-10-07

    Follicle stimulating hormone (FSH) has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF). To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally. Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300) either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax) and time of maximal plasma concentrations (tmax)] and extent [area under the plasma concentration-time curve (AUC) and clearance] of absorption of rhFSH were compared. Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours) and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L) in vaginal versus abdominal injections. The AUC(0-infinity) was 1640 versus 1134 IU hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1), longer mean residence time (106.58 versus 70.47 hours), and slower total body clearance (292.2 versus 400.1 mL/hour) were also found in vaginal injection. The vaginal injection mode elicited a rapid

  2. The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections - a pharmacokinetic study

    Science.gov (United States)

    Hsu, Chao-Chin; Kuo, Hsin-Chih; Hsu, Chao-Tien; Gu, Qing

    2009-01-01

    Background Follicle stimulating hormone (FSH) has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF). To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally. Methods Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300) either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax) and time of maximal plasma concentrations (tmax)] and extent [area under the plasma concentration-time curve (AUC) and clearance] of absorption of rhFSH were compared. Results Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours) and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L) in vaginal versus abdominal injections. The AUC0-∞ was 1640 versus 1134 IU·hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1), longer mean residence time (106.58 versus 70.47 hours), and slower total body clearance (292.2 versus 400.1 mL/hour) were also found in vaginal injection. Conclusion The vaginal

  3. Soil-water dynamics and tree water uptake in the Sacramento Mountains of New Mexico (USA): a stable isotope study

    Science.gov (United States)

    Gierke, Casey; Newton, B. Talon; Phillips, Fred M.

    2016-06-01

    In the southwestern United States, precipitation in the high mountains is a primary source of groundwater recharge. Precipitation patterns, soil properties and vegetation largely control the rate and timing of groundwater recharge. The interactions between climate, soil and mountain vegetation thus have important implications for the groundwater supply. This study took place in the Sacramento Mountains, which is the recharge area for multiple regional aquifers in southern New Mexico. The stable isotopes of oxygen and hydrogen were used to determine whether infiltration of precipitation is homogeneously distributed in the soil or whether it is partitioned among soil-water `compartments', from which trees extract water for transpiration as a function of the season. The results indicate that "immobile" or "slow" soil water, which is derived primarily from snowmelt, infiltrates soils in a relatively uniform fashion, filling small pores in the shallow soils. "Mobile" or "fast" soil water, which is mostly associated with summer thunderstorms, infiltrates very quickly through macropores and along preferential flow paths, evading evaporative loss. It was found that throughout the entire year, trees principally use immobile water derived from snowmelt mixed to differing degrees with seasonally available mobile-water sources. The replenishment of these different water pools in soils appears to depend on initial soil-water content, the manner in which the water was introduced to the soil (snowmelt versus intense thunderstorms), and the seasonal variability of the precipitation and evapotranspiration. These results have important implications for the effect of climate change on recharge mechanisms in the Sacramento Mountains.

  4. Uptake of dietary milk miRNAs by adult humans: a validation study [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Amanda Auerbach

    2016-04-01

    Full Text Available Breast milk is replete with nutritional content as well as nucleic acids including microRNAs (miRNAs. In a recent report, adult humans who drank bovine milk appeared to have increased circulating levels of miRNAs miR-29b-3p and miR-200c-3p. Since these miRNAs are homologous between human and cow, these results could be explained by xeno-miRNA influx, endogenous miRNA regulation, or both. More data were needed to validate the results and explore for additional milk-related alterations in circulating miRNAs. Samples from the published study were obtained, and 223 small RNA features were profiled with a custom OpenArray, followed by individual quantitative PCR assays for selected miRNAs. Additionally, small RNA sequencing (RNA-seq data obtained from plasma samples of the same project were analyzed to find human and uniquely bovine miRNAs. OpenArray revealed no significantly altered miRNA signals after milk ingestion, and this was confirmed by qPCR. Plasma sequencing data contained no miR-29b or miR-200c reads and no intake-consistent mapping of uniquely bovine miRNAs. In conclusion, the results do not support transfer of dietary xenomiRs into the circulation of adult humans.

  5. Antenatal care and uptake of HIV testing among pregnant women in sub-Saharan Africa: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Jayleen K L Gunn

    2016-01-01

    Full Text Available Introduction: Current guidelines recommend inclusion of HIV testing in routine screening tests for all pregnant women. For this reason, antenatal care (ANC represents a vital component of efforts to prevent mother-to-child transmission (PMTCT of HIV. To elucidate the relationship between ANC services and HIV testing among pregnant women in sub-Saharan Africa, we undertook an analysis of data from four countries. Methods: Four countries (Congo, Mozambique, Nigeria and Uganda were purposively selected to represent unique geographical regions of sub-Saharan Africa. Using Demographic and Health Survey datasets, weighted crude and adjusted logistic regression models were used to explore factors that influenced HIV testing as part of ANC services. The study was approved by the Institutional Review Board of the University of Arizona. Results: Pooled results showed that 60.7% of women received HIV testing as part of ANC. Ugandan women had the highest rate of HIV testing as part of ANC (81.5% compared with women in Mozambique (69.4%, Nigeria (54.4% and Congo (45.4%. Difficulty reaching a health facility was a barrier in Congo and Mozambique but not Nigeria or Uganda. HIV testing rates were lower in rural areas, among the poorest women, the least educated and those with limited knowledge of HIV. In every country, crude regression analyses showed higher odds of being tested for HIV if women received their ANC services from a skilled attendant compared with an unskilled attendant. After adjusting for confounders, women in the total sample had 1.78 (99% CI: 1.45–2.18 times the odds of having an HIV test as part of their ANC if they went to a skilled attendant compared with an unskilled attendant. Conclusions: There is a need for integration of HIV testing into routine ANC service to increase opportunities for PMTCT programmes to reach HIV-positive pregnant women. Attention should be paid to the expansion of outreach services for women in rural settings

  6. A short-term study to evaluate the uptake and accumulation of arsenic in Asian willow (Salix sp.) from arsenic-contaminated water.

    Science.gov (United States)

    Chen, Guangcai; Zou, Xiaoli; Zhou, Yuan; Zhang, Jianfeng; Owens, Gary

    2014-03-01

    Five Asian willow species (Salix jiangsuensis J172, Salix matsudana, Salix integra Yizhibi, Salix integra Weishanhu, and Salix mongolica) were evaluated for their potential for phytofiltration of arsenic (As) from synthetically contaminated waters. Arsenic accumulation, tolerance, uptake influx, and phytofiltration ability of the five willow species were examined under hydroponic conditions in a glasshouse. Short-term exposure (2 weeks) to solutions containing 80 μmol L(-1) arsenate (As(V)), resulted in significant accumulation of As in all willow species. Arsenic concentration in plant roots ranged from 322 mg kg(-1) dry weight (DW) for S. matsudana to 604 mg kg(-1) (DW) for S. integra Yizhibi. S. integra Yizhibi decreased As(V) concentration in water from 3.87 to 1.89 μmol L(-1) (290 to 142 μg L(-1)) over 168 h, which is 50 % of the total As(V) in the solution. The results suggested that even though Asian willow was not a traditional aquatic species, it still had significant potential for phytofiltration of As from contaminated waters. Of the five willow species studied, S. integra Yizhibi had the greatest capacity to remove As from As-contaminated waters. Thus, Asian willow has significant potential for the phytofiltration of As and may also be suitable for practical phytoremediation of As in highly water-logged areas.

  7. Kinetic study of phytotoxicity induced by foliar lead uptake for vegetables exposed to fine particles and implications for sustainable urban agriculture.

    Science.gov (United States)

    Xiong, TianTian; Austruy, Annabelle; Pierart, Antoine; Shahid, Muhammad; Schreck, Eva; Mombo, Stéphane; Dumat, Camille

    2016-08-01

    At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption.

  8. Exosomes: Mechanisms of Uptake

    Directory of Open Access Journals (Sweden)

    Kelly J. McKelvey

    2015-07-01

    Full Text Available Exosomes are 30–100 nm microvesicles which contain complex cellular signals of RNA, protein and lipids. Because of this, exosomes are implicated as having limitless therapeutic potential for the treatment of cancer, pregnancy complications, infections, and autoimmune diseases. To date we know a considerable amount about exosome biogenesis and secretion, but there is a paucity of data regarding the uptake of exosomes by immune and non- immune cell types (e.g., cancer cells and the internal signalling pathways by which these exosomes elicit a cellular response. Answering these questions is of para‐ mount importance.

  9. Exosomes: Mechanisms of Uptake

    Directory of Open Access Journals (Sweden)

    Kelly J. McKelvey

    2015-07-01

    Full Text Available Exosomes are 30–100 nm microvesicles which contain complex cellular signals of RNA, protein and lipids. Because of this, exosomes are implicated as having limitless therapeutic potential for the treatment of cancer, pregnancy complications, infections, and autoimmune diseases. To date we know a considerable amount about exosome biogenesis and secretion, but there is a paucity of data regarding the uptake of exosomes by immune and non-immune cell types (e.g., cancer cells and the internal signalling pathways by which these exosomes elicit a cellular response. Answering these questions is of paramount importance.

  10. In situ ultrasound-assisted preparation of Fe3O4@MnO2 core-shell nanoparticles integrated with ion co-precipitation for multielemental analysis by total reflection X-ray fluorescence

    Science.gov (United States)

    Nourbala-Tafti, Elaheh; Romero, Vanesa; Lavilla, Isela; Dadfarnia, Shayesteh; Bendicho, Carlos

    2017-05-01

    In this work, a new analytical approach based on in situ ultrasound-assisted preparation of manganese dioxide coated magnetite nanoparticles (Fe3O4@MnO2 NPs) was applied for extraction and preconcentration of Ni, Cu, Zn, Tl, Pb, Bi and Se. The Fe3O4@MnO2 core-shell nanocomposite was synthesized by application of high-intensity sonication to an aqueous reaction medium in the presence of the target analytes, which are trapped during NPs formation. In this way, synthesis of the nanosorbent and extraction can be simultaneously accomplished within only 30 s. After the extraction step, the resulting Fe3O4@MnO2 NPs enriched with the target analytes were separated by an external magnetic field, so that filtration or centrifugation steps were unnecessary. A 10 μL aliquot of the solid phase was deposited onto a sample carrier (quartz reflector) and directly analyzed by total-reflection X-ray fluorescence (TXRF) without the need for an elution step. A comprehensive characterization of the Fe3O4@MnO2 NPs was carried out by transmission electron microscopy and TXRF. Detection limits ranged from 0.19 to 0.98 μg L- 1 depending on the analyte. Enrichment factors in the range of 402-540 were obtained. The repeatability expressed as relative standard deviation was around 1.7% (N = 5). The accuracy of the proposed method was assessed by analyzing the certified reference material BCR®-610 (groundwater). An effective, simple, rapid and sensitive procedure for multielemental analysis of water samples was accomplished.

  11. The role of ABC proteins Aus1p and Pdr11p in the uptake of external sterols in yeast: dehydroergosterol fluorescence study

    DEFF Research Database (Denmark)

    Kohut, Peter; Wüstner, Daniel; Hronska, L;

    2011-01-01

    applied the fluorescent ergosterol analog dehydroergosterol (DHE) to monitor the initial steps of sterol uptake by three independent approaches: fluorescence spectroscopy, fluorescence microscopy and sterol quantification by HPLC. Using specific fluorescence characteristics of DHE we showed that the entry...... of sterol molecules into plasma membrane is not spontaneous but requires assistance of two ABC (ATP-binding cassette) pumps--Aus1p or Pdr11p. DHE taken up by uptake-competent hem1ΔAUS1PDR11 cells could be directly visualized by UV-sensitive wide field fluorescence microscopy. HPLC analysis of sterols...... revealed significant amounts of exogenous ergosterol and DHE (but not cholesterol) associated with uptake-deficient hem1Δaus1Δpdr11Δ cells. Fluorescent sterol associated with these cells did not show the characteristic emission spectrum of membrane-integrated DHE. The amount of cell-associated DHE...

  12. Direct demonstration of tissue uptake of an inhaled drug: proof-of-principle study using matrix-assisted laser desorption ionization mass spectrometry imaging.

    Science.gov (United States)

    Fehniger, Thomas E; Végvári, Akos; Rezeli, Melinda; Prikk, Kaiu; Ross, Peeter; Dahlbäck, Magnus; Edula, Goutham; Sepper, Ruth; Marko-Varga, György

    2011-11-01

    Drug therapy is often directed to specific organ and tissue compartments where the mode of action of the compound affects specifically targeted biological processes. However, the direct measurement of drug uptake in terms of a time kinetic and concentrations attained at the local sites has not been readily available as a clinical index for most drugs. A proof-of-principle study was conducted to test the utility of applying matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) to demonstrate the qualitative distribution pattern of a locally administered drug within tissue sites of targeted action. Here we have measured the occurrence of an inhaled bronchodilator, the muscarinic receptor antagonist ipratropium, within human bronchial biopsies obtained by fiber optic bronchoscopy shortly after dosing exposure. Cryo-preserved biopsy samples from five subjects being evaluated for airway obstruction or potential tumor development were prepared as thin frozen sections. Samples coated with a MALDI matrix were analyzed by a MALDI LTQ Orbitrap XL mass spectrometer at large (100 μm) and small (30 μm) raster sizes. Our results demonstrate that ipratropium is rapidly absorbed into the airway wall. Ipratropium parent ion (m/z 332.332) and daughter ions (m/z 166.2 and 290.2) were coincidently partitioned within submucosal spaces containing targeted airway smooth muscle in four out of five subjects. The signal intensity of ipratropium fragment ions provided estimates that local drug concentrations between 3 and 80 nM were achieved within the airway wall. To our knowledge, this is the first reported study in applying MALDI-MSI to demonstrate the localization of a drug administered at therapeutic levels. The study highlights the potential benefit of MALDI-MSI to provide important measurements of drug efficacy in clinical settings.

  13. Effects of zinc on cadmium uptake by spring wheat (Triticum aestivum, L.): long-time hydroponic study and short-time 109Cd tracing study

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhong-qiu; ZHU Yong-guan; CAI Yun-long

    2005-01-01

    To investigate effects of Zn on Cd uptake by spring wheat (Triticum aestivum, L.) in solution culture, long-time hydroponic experiment (1 month) (Experiment 1) and short-time Cd isotope (109Cd) tracing experiment (24 h) (Experiment 2) were conducted. In Experiment 1, spring wheat (cv. Brookton) was grown in nutrient solution at uniform cadmium concentration of 20μ mol/L and 10 zinc concentrations (0, 1, 5, 10, 20, 100, 200, 500, 1000, 2000 μ mol/L). In Experiment 2, spring wheat seedlings,pre-cultivated in complete nutrient solution, were treated with 109Cd of uniform activity and the same series of Zn concentrations as those in Experiment 1 for 24 h. Cd concentrations in shoots and roots in Experiment 1 increased marginally but not consistently with Zn increasing at Zn rates of 1~200 μmol/L, and then decreased significantly at high rates (>200 μ mol/L). In Experiment 2, the response of 109Cd activities in shoots and roots to increasing Zn was greatly similar to the response of Cd concentrations to Zn increasing in Experiment 1. The results of the two experiments indicated that the short-time and long-time exposure of spring wheat to Zn had similar effects on Cd accumulation.

  14. {sup 18}F-FDG uptake as a prognostic variable in primary differentiated thyroid cancer incidentally detected by PET/CT: a multicentre study

    Energy Technology Data Exchange (ETDEWEB)

    Piccardo, Arnoldo [Galliera Hospital, Department of Nuclear Medicine, Genoa (Italy); E.O. Ospedali Galliera, Department of Nuclear Medicine, Genoa (Italy); Puntoni, Matteo [Galliera Hospital, Clinical Trial Unit, Office of the Scientific Director, Genoa (Italy); Bertagna, Francesco; Giubbini, Raffaele [University of Brescia and Spedali Civili di Brescia, Department of Nuclear Medicine, Brescia (Italy); Treglia, Giorgio; Ceriani, Luca; Giovanella, Luca [Oncology Institute of Southern Switzerland, Department of Nuclear Medicine and PET/CT Centre, Bellinzona (Switzerland); Foppiani, Luca [Galliera Hospital, Internal Medicine, Genoa (Italy); Arecco, Federico; Bardesono, Francesca; Orlandi, Fabio [University of Turin, Presidio Sanitario Gradenigo, Department of Oncology, Turin (Italy); Naseri, Mehrdad; Cabria, Manlio [Galliera Hospital, Department of Nuclear Medicine, Genoa (Italy); Cistaro, Angelina [IRMET, PET Centre, Turin (Italy)

    2014-08-15

    Our aim was to investigate the association between {sup 18}F-fluorodeoxyglucose (FDG) uptake and event-free survival in patients in whom a differentiated thyroid cancer (DTC) was detected by {sup 18}F-FDG positron emission tomography (PET)/CT. Among 884 focal {sup 18}F-FDG PET thyroid incidentalomas referred to our 4 Nuclear Medicine Departments, we investigated 54 patients in whom a DTC was confirmed and a clinical follow-up was available. The ratio between maximum standardized uptake value (SUV{sub max}) of DTC and SUV{sub mean} of the liver (SUV ratio) was recorded for each scan. All patients underwent total thyroidectomy and {sup 131}I remnant ablation. After a median follow-up of 39 months we assessed the outcome. The association between disease persistence/progression, {sup 18}F-FDG uptake and other risk factors (T, N, M and histological subtype) was evaluated through univariate and multivariate analyses. Of the 54 patients, 39 achieved complete remission. The remaining 15 showed persistence/progression of disease. High {sup 18}F-FDG uptake, i.e. SUV ratio ≥3, showed a low positive predictive value (48 %). Low {sup 18}F-FDG uptake (SUV ratio < 3) displayed a high negative predictive value (93 %). The median of SUV ratios in T1-T2 (2.2), in M0 (2.7) and in non-virulent subtypes (2.7) were significantly lower (p < 0.03) than in T3-T4 (5.0), M1 (7.3) and virulent subtypes (6.0). Kaplan-Maier analysis showed a significant association between high {sup 18}F-FDG uptake and disease persistence/progression (p = 0.001). When we adjusted risk estimates by using a multivariate Cox model, only T (p = 0.05) remained independently associated with disease persistence/progression. An intense {sup 18}F-FDG uptake of the primary DTC is associated with persistence/progression of disease. However, when all other prognostic factors have been taken into account, {sup 18}F-FDG uptake does not add further prognostic information. (orig.)

  15. Patterns of radioiodine uptake by the lactating breast

    Energy Technology Data Exchange (ETDEWEB)

    Bakheet, S.M. (Dept. of Radiology, King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia)); Hammami, M.M. (Dept. of Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia))

    1994-07-01

    Breast uptake of radioiodine, if not suspected, may be misinterpreted as thyroid cancer metastasis to the lung. To characterize the patterns of radioiodine breast uptake, we retrospectively studied 20 radioiodine scans that were performed within 1 week of cessation of breast feeding. Four patterns of uptake were identified: ''full'', ''focal'', ''crescent'' and ''irregular''. The uptake was asymmetric in 60% (left>right in 45%, right>left in 15%), symmetric in 25% and unilateral in 15% of cases. A characteristic full bilateral uptake was present in 40% of cases. In three cases with the irregular pattern, caused in part by external contamination with radioactive milk, the uptake closely mimicked lung metastases. Delayed images, obtained in one case, showed an apparent radioiodine shift from the breast to the thyroid, suggesting that the presence of breast uptake can modulate radioiodine uptake by thyroid tissue. In a case of unilateral breast uptake, a history of mastitis was obtained, which to our knowledge has not been previously reported. Breast uptake of radioiodine may take several scintigraphic patterns that are not always characteristic of the lactating breast and may affect the apparent extent of thyroid remnant/metastasis. (orig.)

  16. FDG uptake in the pathologically proven papillary thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Sung; Yun, Mi Jin; Cho, Arthur; Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-02-15

    Metastatic thyroid cancers with I-131 uptake have been known to show no increase of FDG uptake whereas those without I-131 uptake tend to demonstrate increased uptake on PET. In this study, we evaluated the degree of FDG uptake in primary thyroid cancers of papillary histology before surgery. Forty FDG PET studies were performed on the patients who had papillary cancer proven by fine needle aspiration. The degree of FDG uptake was visually categorized as positive or negative (positive if the tumor showed discernible FDG; negative if the tumor didn't) and the peak standard uptake value (peak SUV) of the papillary thyroid cancer (PTC) were compared with the size of PTC. The mean size of 26 PTC with positive FDG uptake was 1.9{+-} 1.4 cm (0.5 {approx} 5 cm). In 13 PTC with negative FDG uptake, the mean size of those was 0.5 {+-} 0.2 cm (0.2 {approx} 0.9 cm). All PTC larger than 1 cm (2.5 {+-}1.4 cm, 1 {approx} 5 cm) have positive FDG uptake (peak SUV = 6.4 {+-} 5.7, 1.7 {approx} 22.7). Among the micropapillary thyroid cancer (microPTC; PTC smaller than 1 cm), 8 microPTC show positive FDG uptake (peak SUV = 2.9 {+-} 1.3, 1.7 {approx} 5.5), while 13 microPTC show negative finding (peak SUV 1.3 {+-} 0.2, 1.1{approx} 1.7). The size of microPTC with positive FDG uptake is significantly larger than that of microPTC with negative FDG uptake (0.7 {+-} 0.1cm vs 0.4 {+-} 0.2 cm, {rho} = 0.01). All PTCs larger than 1cm show positive FDG uptake in our study. In other words, thyroid lesions larger than 1cm with negative FDG uptake are unlikely to be PTC. So far, only poorly differentiated thyroid cancers are known to show increased FDG uptake. Our results seem to be contradictory to what is known in the literature. Further study is needed to understand better the significance of increased FDG uptake in PTC in relation to expression of NIS and GLUT.

  17. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence.

    Science.gov (United States)

    Tian, Shengke; Lu, Lingli; Xie, Ruohan; Zhang, Minzhe; Jernstedt, Judith A; Hou, Dandi; Ramsier, Cliff; Brown, Patrick H

    2014-01-01

    Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF) to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO4 alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant "GroZyme" resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using μ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower.

  18. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L. plants. Studies utilizing micro X-ray florescence

    Directory of Open Access Journals (Sweden)

    Shengke eTian

    2015-01-01

    Full Text Available Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied Zn formulations in sunflower (Helianthus annuus L. and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (Helianthus annuus L. and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by ICP-MS, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower pertioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off as compared with an equimolar concentration of ZnSO4 alone. The addition of macronutrients N, P, K (commercial product CleanStart to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant GroZyme resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using µ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower.

  19. Uptake and depuration of gold nanoparticles in Daphnia magna

    DEFF Research Database (Denmark)

    Skjolding, Lars Michael; Kern, Kristina; Hjorth, Rune

    2014-01-01

    This study presents a series of short-term studies (total duration 48 h) of uptake and depuration of engineered nanoparticles (ENP) in neonate Daphnia magna. Gold nanoparticles (Au NP) were used to study the influence of size, stabilizing agent and feeding on uptake and depuration kinetics...

  20. Uptake and depuration of gold nanoparticles in Daphnia magna

    DEFF Research Database (Denmark)

    Skjolding, Lars Michael; Kern, Kristina; Hjorth, Rune

    2014-01-01

    This study presents a series of short-term studies (total duration 48 h) of uptake and depuration of engineered nanoparticles (ENP) in neonate Daphnia magna. Gold nanoparticles (Au NP) were used to study the influence of size, stabilizing agent and feeding on uptake and depuration kinetics...

  1. The Uptake by Plants of Diethylstilboestrol and of Its Glucuronide

    DEFF Research Database (Denmark)

    Gregers Hansen, B.

    1964-01-01

    The uptake of diethylstilboestrol and its glucuronide by plants could, under certain circumstances, present a potential health hazard. The relative uptake of the two compounds has therefore been studied in rye grass, red clover, mushrooms, and maize in pot and water culture experiments. It is con......The uptake of diethylstilboestrol and its glucuronide by plants could, under certain circumstances, present a potential health hazard. The relative uptake of the two compounds has therefore been studied in rye grass, red clover, mushrooms, and maize in pot and water culture experiments...

  2. Semi-automatic analysis of standard uptake values in serial PET/CT studies in patients with lung cancer and lymphoma

    Directory of Open Access Journals (Sweden)

    Ly John

    2012-04-01

    Full Text Available Abstract Background Changes in maximum standardised uptake values (SUVmax between serial PET/CT studies are used to determine disease progression or regression in oncologic patients. To measure these changes manually can be time consuming in a clinical routine. A semi-automatic method for calculation of SUVmax in serial PET/CT studies was developed and compared to a conventional manual method. The semi-automatic method first aligns the serial PET/CT studies based on the CT images. Thereafter, the reader selects an abnormal lesion in one of the PET studies. After this manual step, the program automatically detects the corresponding lesion in the other PET study, segments the two lesions and calculates the SUVmax in both studies as well as the difference between the SUVmax values. The results of the semi-automatic analysis were compared to that of a manual SUVmax analysis using a Philips PET/CT workstation. Three readers did the SUVmax readings in both methods. Sixteen patients with lung cancer or lymphoma who had undergone two PET/CT studies were included. There were a total of 26 lesions. Results Linear regression analysis of changes in SUVmax show that intercepts and slopes are close to the line of identity for all readers (reader 1: intercept = 1.02, R2 = 0.96; reader 2: intercept = 0.97, R2 = 0.98; reader 3: intercept = 0.99, R2 = 0.98. Manual and semi-automatic method agreed in all cases whether SUVmax had increased or decreased between the serial studies. The average time to measure SUVmax changes in two serial PET/CT examinations was four to five times longer for the manual method compared to the semi-automatic method for all readers (reader 1: 53.7 vs. 10.5 s; reader 2: 27.3 vs. 6.9 s; reader 3: 47.5 vs. 9.5 s; p Conclusions Good agreement was shown in assessment of SUVmax changes between manual and semi-automatic method. The semi-automatic analysis was four to five times faster to perform than the manual analysis. These findings show the

  3. Explaining variation in Down's syndrome screening uptake

    DEFF Research Database (Denmark)

    Crombag, Neeltje M T H; Vellinga, Ynke E; Kluijfhout, Sandra A

    2014-01-01

    BACKGROUND: The offer of prenatal Down's syndrome screening is part of routine antenatal care in most of Europe; however screening uptake varies significantly across countries. Although a decision to accept or reject screening is a personal choice, it is unlikely that the widely differing uptake...... rates across countries can be explained by variation in individual values alone.The aim of this study was to compare Down's syndrome screening policies and programmes in the Netherlands, where uptake is relatively low ( 90% respectively....... RESULTS: There were many similarities in the demographics, healthcare systems, government abortion legislation and Down's syndrome screening policy across the studied countries. However, the additional cost for Down's syndrome screening over and above standard antenatal care in the Netherlands...

  4. Equity in human papilloma virus vaccination uptake? : sexual behaviour, knowledge and demographics in a cross-sectional study in (un)vaccinated girls in the Netherlands

    NARCIS (Netherlands)

    Mollers, Madelief; Lubbers, Karin; Spoelstra, Symen K; Weijmar Schultz, Willibrordus; Daemen, Toos; Westra, Tjalke A; van der Sande, Marianne A B; Nijman, Hans W; de Melker, Hester E; Tami, Adriana

    2014-01-01

    Background: In the Netherlands, human papillomavirus (HPV) vaccination is part of a national program equally accessible for all girls invited for vaccination. To assess possible inequalities in vaccine uptake, we investigated differences between vaccinated and unvaccinated girls with regard to vario

  5. Examining inequalities in uptake of maternal health care and choice of provider in underserved urban areas of Mumbai, India: A mixed methods study

    NARCIS (Netherlands)

    G. Alcock (Glyn); S. Das (Sushmita); N.S. More (Neena Shah); K. Hate (Ketaki); S. More (Sharda); S. Pantvaidya (Shanti); D. Osrin (David); A.J. Houweling (Tanja)

    2015-01-01

    textabstractBackground: Discussions of maternity care in developing countries tend to emphasise service uptake and overlook choice of provider. Understanding how families choose among health providers is essential to addressing inequitable access to care. Our objectives were to quantify the determin

  6. PET studies on P-glycoprotein function in the blood-brain barrier : How it affects uptake and binding of drugs within the CNS

    NARCIS (Netherlands)

    Elsinga, PH; Hendrikse, Nelis; Bart, J; Vaalburg, W; van Waarde, A

    2004-01-01

    Permeability of the blood-brain barrier (BBB) is one of the factors determining the bioavailability of therapeutic drugs. The BBB only allows entry of lipophilic compounds with low molecular weights by passive diffusion. However, many lipophilic drugs show negligible brain uptake. They are substrate

  7. Equity in human papilloma virus vaccination uptake? : sexual behaviour, knowledge and demographics in a cross-sectional study in (un)vaccinated girls in the Netherlands

    NARCIS (Netherlands)

    Mollers, Madelief; Lubbers, Karin; Spoelstra, Symen K; Weijmar Schultz, Willibrordus; Daemen, Toos; Westra, Tjalke A; van der Sande, Marianne A B; Nijman, Hans W; de Melker, Hester E; Tami, Adriana

    2014-01-01

    Background: In the Netherlands, human papillomavirus (HPV) vaccination is part of a national program equally accessible for all girls invited for vaccination. To assess possible inequalities in vaccine uptake, we investigated differences between vaccinated and unvaccinated girls with regard to vario

  8. Barriers and motivators to voluntary medical male circumcision uptake among different age groups of men in Zimbabwe: results from a mixed methods study.

    Directory of Open Access Journals (Sweden)

    Karin Hatzold

    Full Text Available BACKGROUND: We conducted quantitative and qualitative studies to explore barriers and motivating factors to VMMC for HIV prevention, and to assess utilization of existing VMMC communication channels. METHODS AND FINDINGS: A population-based survey was conducted with 2350 respondents aged 15-49. Analysis consisted of descriptive statistics and bivariate analysis between circumcision and selected demographics. Logistic regression was used to determine predictors of male circumcision uptake compared to intention to circumcise. Focus group discussions (FGDs were held with men purposively selected to represent a range of ethnicities. 68% and 53% of female/male respondents, respectively, had heard about VMMC for HIV prevention, mostly through the radio (71%. Among male respondents, 11.3% reported being circumcised and 49% reported willingness to undergo VMMC. Factors which men reported motivated them to undergo VMMC included HIV/STI prevention (44%, improved hygiene (26%, enhanced sexual performance (6% and cervical cancer prevention for partner (6%. Factors that deterred men from undergoing VMMC included fear of pain (40%, not believing that they were at risk of HIV (18%, lack of partner support (6%. Additionally, there were differences in motivators and barriers by age. FGDs suggested additional barriers including fear of HIV testing, partner refusal, reluctance to abstain from sex and myths and misconceptions. CONCLUSIONS: VMMC demand-creation messages need to be specifically tailored for different ages and should emphasize non-HIV prevention benefits, such as improved hygiene and sexual appeal, and need to address men's fear of pain. Promoting VMMC among women is crucial as they appear to have considerable influence over men's decision to get circumcised.

  9. End criteria for reaching maximal oxygen uptake must be strict and adjusted to sex and age: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Elisabeth Edvardsen

    Full Text Available OBJECTIVE: To describe different end criteria for reaching maximal oxygen uptake (VO2max during a continuous graded exercise test on the treadmill, and to explore the manner by which different end criteria have an impact on the magnitude of the VO2max result. METHODS: A sample of 861 individuals (390 women aged 20-85 years performed an exercise test on a treadmill until exhaustion. Gas exchange, heart rate, blood lactate concentration and Borg Scale6-20 rating were measured, and the impact of different end criteria on VO2max was studied;VO2 leveling off, maximal heart rate (HRmax, different levels of respiratory exchange ratio (RER, and postexercise blood lactate concentration. RESULTS: Eight hundred and four healthy participants (93% fulfilled the exercise test until voluntary exhaustion. There were no sex-related differences in HRmax, RER, or Borg Scale rating, whereas blood lactate concentration was 18% lower in women (P<0.001. Forty-two percent of the participants achieved a plateau in VO2; these individuals had 5% higher ventilation (P = 0.033, 4% higher RER (P<0.001, and 5% higher blood lactate concentration (P = 0.047 compared with participants who did not reach a VO2 plateau. When using RER ≥1.15 or blood lactate concentration ≥8.0 mmol•L(-1, VO2max was 4% (P = 0.012 and 10% greater (P<0.001, respectively. A blood lactate concentration ≥8.0 mmol•L(-1 excluded 63% of the participants in the 50-85-year-old cohort. CONCLUSIONS: A range of typical end criteria are presented in a random sample of subjects aged 20-85 years. The choice of end criteria will have an impact on the number of the participants as well as the VO2max outcome. Suggestions for new recommendations are given.

  10. Respective contributions of intestinal Niemann-Pick C1-like 1 and scavenger receptor class B type I to cholesterol and tocopherol uptake: in vivo v. in vitro studies.

    Science.gov (United States)

    Reboul, Emmanuelle; Soayfane, Zeina; Goncalves, Aurélie; Cantiello, Michela; Bott, Romain; Nauze, Michel; Tercé, François; Collet, Xavier; Coméra, Christine

    2012-05-01

    The intestinal absorption of cholesterol and lipid micronutrients such as vitamin E has been shown to share some common pathways. The present study aims to further compare the uptake of cholesterol ([3H]cholesterol v. 22-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-23,24-bisnor-5-cholen-3-ol (NBD-cholesterol)) and tocopherol in Caco-2 TC-7 cells and in mouse intestine, with special focus on the respective roles of scavenger receptor class B type I (SR-BI) and Niemann-Pick C1-like 1 (NPC1L1). Conversely to NBD-cholesterol, the uptakes of [3H]cholesterol and tocopherol by Caco-2 cells were impaired by both block lipid transport-1 and ezetimibe, which inhibit SR-BI and NPC1L1, respectively. These inhibitions occurred only when cholesterol or tocopherol was delivered to cells included in micelles that contained biliary acid and at least oleic acid as a lipid. In vivo, after 2 h of digestion in mice, the uptake of the two cholesterol analogues and of tocopherol all showed distinct patterns along the duodenum-jejunum axis. [3H]Cholesterol uptake, which correlated closely to NPC1L1 mRNA expression in wild-type (wt) mice, was strongly inhibited by ezetimibe. Intestinal SR-BI overexpression did not change NPC1L1 expression and led to a significant increase in [3H]cholesterol uptake in the distal jejunum. Conversely, neither ezetimibe treatment nor SR-BI overexpression had an effect on NBD-cholesterol uptake. However, in contrast with SR-BI mRNA expression, tocopherol absorption increased strongly up to the distal jejunum in wt mice where it was specifically inhibited by ezetimibe, and was increased in the proximal intestine of intestinal SR-BI-overexpressing mice. Thus, cholesterol and tocopherol uptakes share common pathways in cell culture models, but display different in vivo absorption patterns associated with distinct contributions of SR-BI and NPC1L1.

  11. Short-term uptake of heavy metals by periphyton algae

    Energy Technology Data Exchange (ETDEWEB)

    Vymazal, J.

    1984-12-31

    The utilization of periphyton for the removal of heavy metals from enriched small streams has been examined. By means of short-term batch laboratory experiments the courses of metal uptake have been studied. For uptake study naturally growing periphyton community and periphytic filamentous algae Cladophora glomerata and Oedogonium rivulare have been used. Uptakes of nine heavy metals (Pb, Cd, Cu, Co, Cr, Ni, Zn, Fe and Mn) have been determined during four hours exposure. In addition the influence of humic substances on heavy metals uptake has been determined. Uptake of all metals increased during four hours exposure but not in the same way. Some metals were removed continuously (Ni, Cr, Fe and Mn), other metals were removed more rapidly during the first hour or first two hours of exposure and then only slight removal continued (Cu, Pb, Cd, Co). Uptake of Zn was rather unambiguous. Results of these experiments suggest that the course of uptake for individual metals could be similar for most periphyton algae. It was established that humic substances significantly reduce heavy metals uptake. The highest decrease of uptake was observed in Cu, Cr, Co and Cd. The results of model experiments are being tested in a pilot scale with respect to the demands of engineering practice. (J.R.)

  12. Enantioselective cellular uptake of chiral semiconductor nanocrystals

    Science.gov (United States)

    Martynenko, I. V.; Kuznetsova, V. A.; Litvinov, I. K.; Orlova, A. O.; Maslov, V. G.; Fedorov, A. V.; Dubavik, A.; Purcell-Milton, F.; Gun'ko, Yu K.; Baranov, A. V.

    2016-02-01

    The influence of the chirality of semiconductor nanocrystals, CdSe/ZnS quantum dots (QDs) capped with L- and D-cysteine, on the efficiency of their uptake by living Ehrlich Ascite carcinoma cells is studied by spectral- and time-resolved fluorescence microspectroscopy. We report an evident enantioselective process where cellular uptake of the L-Cys QDs is almost twice as effective as that of the D-Cys QDs. This finding paves the way for the creation of novel approaches to control the biological properties and behavior of nanomaterials in living cells.

  13. Diffuse FDG renal uptake in lymphoma.

    Science.gov (United States)

    Navalkissoor, Shaunak; Szyszko, Teresa; Gnanasegaran, Gopinath; Nunan, Thomas

    2010-10-01

    In patients presenting with acute renal failure and known/suspected lymphoma, the diagnosis of diffuse renal involvement is important, as there is potential for rapid resolution with chemotherapy. Although FDG is excreted through the kidneys and focal renal disease may be difficult to identify, diffuse renal FDG is more easily recognized and is always abnormal. We report a patient presenting with acute renal failure and suspected lymphoma. F-18 FDG PET/CT study demonstrated diffuse increased FDG uptake in bilaterally enlarged kidneys. Following 1 cycle of chemotherapy, the renal function normalized. An interim F-18 FDG PET/CT demonstrated normal size and FDG uptake within both kidneys.

  14. Uptake of nuclides by plants

    Energy Technology Data Exchange (ETDEWEB)

    Greger, Maria [Stockholm Univ. (Sweden). Dept. of Botany

    2004-04-01

    This review on plant uptake of elements has been prepared to demonstrate how plants take up different elements. The work discusses the nutrient elements, as well as the general uptake and translocation in plants, both via roots and by foliar absorption. Knowledge of the uptake by the various elements within the periodic system is then reviewed. The work also discusses transfer factors (TF) as well as difficulties using TF to understand the uptake by plants. The review also focuses on species differences. Knowledge necessary to understand and calculate plant influence on radionuclide recirculation in the environment is discussed, in which the plant uptake of a specific nuclide and the fate of that nuclide in the plant must be understood. Plants themselves determine the uptake, the soil/sediment determines the availability of the nuclides and the nuclides themselves can interact with each other, which also influences the uptake. Consequently, it is not possible to predict the nuclide uptake in plants by only analysing the nuclide concentration of the soil/substrate.

  15. High intensity interval training in a real world setting: a randomized controlled feasibility study in overweight inactive adults, measuring change in maximal oxygen uptake.

    Directory of Open Access Journals (Sweden)

    Helen Lunt

    Full Text Available BACKGROUND: In research clinic settings, overweight adults undertaking HIIT (high intensity interval training improve their fitness as effectively as those undertaking conventional walking programs but can do so within a shorter time spent exercising. We undertook a randomized controlled feasibility (pilot study aimed at extending HIIT into a real world setting by recruiting overweight/obese, inactive adults into a group based activity program, held in a community park. METHODS: Participants were allocated into one of three groups. The two interventions, aerobic interval training and maximal volitional interval training, were compared with an active control group undertaking walking based exercise. Supervised group sessions (36 per intervention were held outdoors. Cardiorespiratory fitness was measured using VO2max (maximal oxygen uptake, results expressed in ml/min/kg, before and after the 12 week interventions. RESULTS: On ITT (intention to treat analyses, baseline (N = 49 and exit (N = 39 [Formula: see text]O2 was 25.3±4.5 and 25.3±3.9, respectively. Participant allocation and baseline/exit VO2max by group was as follows: Aerobic interval training N =  16, 24.2±4.8/25.6±4.8; maximal volitional interval training N = 16, 25.0±2.8/25.2±3.4; walking N = 17, 26.5±5.3/25.2±3.6. The post intervention change in VO2max was +1.01 in the aerobic interval training, -0.06 in the maximal volitional interval training and -1.03 in the walking subgroups. The aerobic interval training subgroup increased VO2max compared to walking (p = 0.03. The actual (observed, rather than prescribed time spent exercising (minutes per week, ITT analysis was 74 for aerobic interval training, 45 for maximal volitional interval training and 116 for walking (p =  0.001. On descriptive analysis, the walking subgroup had the fewest adverse events. CONCLUSIONS: In contrast to earlier studies, the improvement in cardiorespiratory fitness in a

  16. Effect on the uptake kinetics of serotonin (5-hydroxytryptamine) in platelets from workers with long-term exposure to organic solvents. A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Beving, H.; Kristensson, J.; Malmgren, R.; Olsson, P.; Unge, G.

    1984-08-01

    Six workers from a paint industry were examined concerning the concentration of solvents in the breathing zone, the platelet count and kinetic uptake of serotonin (5-hydroxytryptamine (5-HT)), the serum concentration of calcium, potassium and sodium, and pH. The degree of exposure was found to be moderate. The results showed a decrease in platelet count in whole blood and platelet-rich plasma. The maximum uptake rate for serotonin in platelets (Vmax) was significantly increased compared to that of nonexposed subjects. No changes in the ionic concentration and pH of serum were observed. One worker was reexamined after a six-week period of nonexposure. Though the measured platelet variables were still aberrant, the values approached normal.

  17. Water uptake in the cat flea Ctenocephalides felis (Pulicidae: Siphonaptera).

    Science.gov (United States)

    Thiemann, T; Fielden, L J; Kelrick, M I

    2003-12-01

    To counteract water loss due to excretion, cuticular transpiration and respiration, various groups of arthropods have developed mechanisms for active uptake of water vapor from unsaturated air. In this study, active uptake capabilities and water loss rates were examined in the various developmental stages of the cat flea, Ctenocephalides felis. To determine critical equilibrium humidity, the lowest relative humidity at which active water uptake can occur, pre-desiccated immature and adult fleas were placed in a series of humidity regimes ranging from 44 to 93% RH. Active uptake occurred in larval stages at relative humidities above 53% and in pre-pupae at 75-93% RH. Pupae and adults did not demonstrate active uptake at any humidity. Optimal uptake for larvae occurred between 20 and 30 degrees C. When placed over Drierite (water loss than pre-pupal and pupal stages. Active water uptake is necessary to ensure proper development of the larvae of C. felis. Active uptake ceases after the larval-pupal ecdysis and it appears that adults have lost the ability to actively uptake water.

  18. Contraction stimulates muscle glucose uptake independent of atypical PKC.

    Science.gov (United States)

    Yu, Haiyan; Fujii, Nobuharu L; Toyoda, Taro; An, Ding; Farese, Robert V; Leitges, Michael; Hirshman, Michael F; Mul, Joram D; Goodyear, Laurie J

    2015-11-01

    Exercise increases skeletal muscle glucose uptake, but the underlying mechanisms are only partially understood. The atypical protein kinase C (PKC) isoforms λ and ζ (PKC-λ/ζ) have been shown to be necessary for insulin-, AICAR-, and metformin-stimulated glucose uptake in skeletal muscle, but not for treadmill exercise-stimulated muscle glucose uptake. To investigate if PKC-λ/ζ activity is required for contraction-stimulated muscle glucose uptake, we used mice with tibialis anterior muscle-specific overexpression of an empty vector (WT), wild-type PKC-ζ (PKC-ζ(WT)), or an enzymatically inactive T410A-PKC-ζ mutant (PKC-ζ(T410A)). We also studied skeletal muscle-specific PKC-λ knockout (MλKO) mice. Basal glucose uptake was similar between WT, PKC-ζ(WT), and PKC-ζ(T410A) tibialis anterior muscles. In contrast, in situ contraction-stimulated glucose uptake was increased in PKC-ζ(T410A) tibialis anterior muscles compared to WT or PKC-ζ(WT) tibialis anterior muscles. Furthermore, in vitro contraction-stimulated glucose uptake was greater in soleus muscles of MλKO mice than WT controls. Thus, loss of PKC-λ/ζ activity increases contraction-stimulated muscle glucose uptake. These data clearly demonstrate that PKC-λζ activity is not necessary for contraction-stimulated glucose uptake.

  19. Plant uptake of radionuclides and rhizosphere factors

    Energy Technology Data Exchange (ETDEWEB)

    Arie, Tsutomu; Gouthu, S.; Ambe, Shizuko; Yamaguchi, Isamu [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Hirata, Hiroaki

    1999-03-01

    Influence of soil factors such as nuclide availability, pH, organic carbon, cation exchange capacity (CEC), exchangeable cations (Ca{sup 2+}, Mg{sup 2+}, and K{sup +}), phosphate absorption coefficient (PAC), physical composition of soil (coarse sand, fine sand, silt, and clay), soil texture, and rhizosphere microbes on uptake of radionuclides by plants are studied. (author)

  20. Lysozyme uptake by oxidized starch polymer microgels

    NARCIS (Netherlands)

    Li, Y.; Vries, R.D.; Kleijn, M.; Slaghek, T.; Timmermans, J.; Stuart, M.C.; Norde, W.

    2010-01-01

    With the aim of determining suitable conditions for uptake and release of globular proteins on microgels, we studied the interaction between phosphated, highly cross-linked, negatively charged oxidized potato starch polymer (OPSP) microgel particles and lysozyme from hen eggs. Our microgel shows a

  1. Water Uptake Mechanism in Crispy Bread Crust

    NARCIS (Netherlands)

    Nieuwenhuijzen, van N.H.; Meinders, M.B.J.; Tromp, R.H.; Hamer, R.J.; Vliet, van T.

    2008-01-01

    Crispness is an important quality characteristic of dry solid food products such as crispy rolls. Its retention is directly related to the kinetics of water uptake by the crust. In this study, a method for the evaluation of the water sorption kinetics in bread crust is proposed. Two different sorpti

  2. Results of a Study Investigating the Plant Uptake of Explosive Residues From Compost of Explosives-Contaminated Soil Obtained from the Umatilla Army Depot Activity

    Science.gov (United States)

    1998-11-01

    and explosive by-products in nine plant species. These plant species included: Radish ( Raphanus sativus L. variety Cherry Belle), Kale (Brassica...Umatilla Army Depot Activity Vegetable Crops: • Radish ( Raphanus sativus L. variety Cherry Belle) - A quick-growing root crop which can be grown to...seeds of radish ( Raphanus sativus variety Cherry Belle), lettuce Plant Uptake of Explosives 3-18 Umatilla Army Depot Activity o < o ft <u Q >> T3

  3. Effect of external potassium (K) supply on the uptake of {sup 137}Cs by spring wheat (Triticum aestivum cv. Tonic): a large-scale hydroponic study

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Y.-G. E-mail: yongguan.zhu@adelaide.edu.au

    2001-07-01

    A large-scale hydroponic experiment was carried out in a non-controlled greenhouse. Spring wheat plants were grown to maturity at four levels of external K concentration (2, 4, 20 and 40 mg l{sup -1}) and one concentration of radiocaesium (8 Bq ml{sup -1}). Concentrations of K and radiocaesium in the growth solution were closely monitored, and replenishments were made upon depletion. K effectively competed with radiocaesium in terms of root uptake. Activity concentrations of radiocaesium in plants differed significantly between the four K treatments; the activity concentration at the lowest external K concentration being 100 times higher than that at the highest K level. The relationship between radiocaesium uptake and external K level could be described by a negative power function; this showed that when the K level reached around 12 mg l{sup -1}, further increases in the external K level resulted only in slight changes in its inhibitory effect. As a result of this inhibitory effect of potassium supply, concentrations of radiocaesium in plant tissues, grains in particular, were greatly reduced at high external K concentration. Mechanisms involved in Cs-K interaction in root uptake are also discussed.

  4. Clarithromycin is absorbed by an intestinal uptake mechanism that is sensitive to major inhibition by rifampicin: results of a short-term drug interaction study in foals.

    Science.gov (United States)

    Peters, Jette; Eggers, Karen; Oswald, Stefan; Block, Wiebke; Lütjohann, Dieter; Lämmer, Marc; Venner, Monica; Siegmund, Werner

    2012-03-01

    Pulmonary penetration of clarithromycin (CLR) in epithelial lining fluid (ELF) and bronchoalveolar lavage cells (BALCs) can be influenced by CYP3A4, by P-glycoprotein, and, according to our hypothesis, by a member of the organic anion-transporting protein (OATP) family, for which rifampicin (RIF) is inhibiting in single doses but inducing after long-term coadministration. To assess the partial inhibitory effect, we measured absorption and pulmonary distribution of CLR after short-term (2.5-day) coadministration of RIF, after which up-regulation is not expected. The drug interaction study was performed with five doses (12-h interval) of CLR (7.5 mg/kg) and RIF (10 mg/kg) in nine healthy foals; horse transporters are very similar in protein sequence and transcriptional regulation to the human analogs. RIF was equally distributed in ELF but reached half the plasma levels in BALCs. The deacetylated metabolite accumulated 1.4- to 6-fold in ELF and 8- to 60-fold in BALCs. CLR did not significantly influence the distribution of RIF. CLR and 14-hydroxyclarithromycin (14OH-CLR) accumulated approximately 20- to 40-fold and 1.5- to 4.5-fold in ELF and 300- to 1800-fold and 25- to 90-fold in BALCs, respectively. With RIF, plasma levels of CLR decreased by more than 70% without changes in 14OH-CLR formation, the half-lives of CLR and 14OH-CLR, and the 4β-hydroxycholesterol/cholesterol ratio (a surrogate for CYP3A4 induction). CLR was an inhibitor of OATP1B3 (IC(50) = 9.50 ± 3.50 μM), OATP1B1 (IC(50) = 46.0 ± 2.27 μM), OATP1A2 (IC(50) = 92.6 ± 1.49 μM), and OATP2B1 (IC(50) = 384 ± 5.30 μM) but was not a substrate for these transporters in transfected human embryonic kidney cells. In conclusion, despite having no significant inducing effects, RIF decreased plasma levels of CLR below the minimal inhibitory concentration required to inhibit 90% of growth of pathogenic bacteria, most likely through inhibition of an unknown intestinal uptake transporter.

  5. Cobalt uptake and binding in human red blood cells

    DEFF Research Database (Denmark)

    Simonsen, Lars Ole; Brown, Anthony M; Harbak, Henrik

    2011-01-01

    The basal uptake and cytoplasmic binding of cobalt was studied in human red cells using (57)Co as tracer. The basal uptake is linear with time, at a rate of about 10 µmol (l cells)(-1) h(-1) at 100 µM [Co(2+)](o), and is almost irreversible, as there is hardly any efflux into excess EDTA. Ionophore...

  6. Cerebral ammonia uptake and accumulation during prolonged exercise in humans

    DEFF Research Database (Denmark)

    Nybo, Lars; Dalsgaard, Mads K.; Steensberg, Adam

    2005-01-01

    We evaluated whether peripheral ammonia production during prolonged exercise enhances the uptake and subsequent accumulation of ammonia within the brain. Two studies determined the cerebral uptake of ammonia (arterial and jugular venous blood sampling combined with Kety-Schmidt-determined cerebra...

  7. Exploring the Relationship between Characteristics of Recasts and Learner Uptake

    Science.gov (United States)

    Sheen, Younghee

    2006-01-01

    This study presents a taxonomy of the recasts that arose in communicative ESL and EFL classrooms. The taxonomy is used to examine the relationship between different characteristics of recasts and learner uptake/repair. Characteristics that were significantly related to uptake were the length of recasts (short vs. long), the linguistic focus…

  8. Diffusely increased bone scintigraphic uptake in patellofemoral pain syndrome

    OpenAIRE

    Naslund, J.; Odenbring, S; Naslund, U; Lundeberg, T

    2005-01-01

    Objectives: Painful disorders of the patellofemoral joint are one of the most frequent complaints in orthopaedic and sports medicine. The aims of this study were to determine whether bone scintigrams of patients suffering from patellofemoral pain syndrome (PFPS) show diffuse uptake and in what bony compartment of the knee uptake, if any, was localised.

  9. Effect of increasing pump speed during exercise on peak oxygen uptake in heart failure patients supported with a continuous-flow left ventricular assist device. A double-blind randomized study

    DEFF Research Database (Denmark)

    Jung, Mette Holme; Hansen, Peter Bo; Sander, Kaare

    2014-01-01

    AIMS: Continuous-flow left ventricular assist device (CF-LVAD) implantation is associated with improved quality of life, but the effect on exercise capacity is less well documented. It is uncertain whether a fixed CF-LVAD pump speed, which allows for sufficient circulatory support at rest, remains...... adequate during exercise. The aim of this study was to evaluate the effects of fixed versus incremental pump speed on peak oxygen uptake (peak VO2) during a maximal exercise test. METHODS AND RESULTS: In CF-LVAD (HeartMate II) patients exercise testing measuring peak oxygen uptake (VO2) was performed...... on an ergometer bike twice in one day: once with fixed pump speed (testfix) and once with incremental pump speed (testinc). The order of testfix and testinc in each patient was determined by randomization. During testinc pump speed was increased from the baseline value by 400 rpm/2 min. Fourteen patients (aged 23...

  10. Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

    OpenAIRE

    劒持,堅志

    1980-01-01

    The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

  11. Effect of sepsis on calcium uptake and content in skeletal muscle and regulation in vitro by calcium of total and myofibrillar protein breakdown in control and septic muscle: Results from a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Benson, D.W.; Hasselgren, P.O.; Hiyama, D.T.; James, J.H.; Li, S.; Rigel, D.F.; Fischer, J.E.

    1989-07-01

    Because high calcium concentration in vitro stimulates muscle proteolysis, calcium has been implicated in the pathogenesis of increased muscle breakdown in different catabolic conditions. Protein breakdown in skeletal muscle is increased during sepsis, but the effect of sepsis on muscle calcium uptake and content is not known. In this study the influence of sepsis, induced in rats by cecal ligation and puncture, on muscle calcium uptake and content was studied. Sixteen hours after cecal ligation and puncture or sham operation, calcium content of the extensor digitorum longus (EDL) and soleus (SOL) muscles was determined with an atomic absorption spectrometer. Calcium uptake was measured in intact SOL muscles incubated in the presence of calcium 45 (45Ca) for between 1 and 120 minutes. Total and myofibrillar protein breakdown was determined in SOL muscles, incubated in the presence of different calcium concentrations (0; 2.5; 5.0 mmol/L), and measured as release into the incubation medium of tyrosine and 3-methylhistidine (3-MH), respectively. Calcium content was increased by 51% (p less than 0.001) during sepsis in SOL and by 10% (p less than 0.05) in EDL muscle. There was no difference in 45Ca uptake between control and septic muscles during the early phase (1 to 5 minutes) of incubation. During more extended incubation (30 to 120 minutes), muscles from septic rats took up significantly more 45Ca than control muscles (p less than 0.05). Tyrosine release by incubated SOL muscles from control and septic rats was increased when calcium was added to the incubation medium, and at a calcium concentration of 2.5 mmol/L, the increase in tyrosine release was greater in septic than in control muscle. Addition of calcium to the incubation medium did not affect 3-MH release in control or septic muscle.

  12. Endocytotic uptake of nutrients in carnivorous plants.

    Science.gov (United States)

    Adlassnig, Wolfram; Koller-Peroutka, Marianne; Bauer, Sonja; Koshkin, Edith; Lendl, Thomas; Lichtscheidl, Irene K

    2012-07-01

    Carnivorous plants trap, digest and absorb animals in order to supplement their mineral nutrition. Nutrients absorbed by the plant include different nitrogen species, phosphate, potassium, trace elements and small organic compounds. Uptake is usually thought to be performed via specific channels, but this study provides evidence that endocytosis is involved as well. Traps of the carnivorous plants Nepenthes coccinea, Nepenthes ventrata, Cephalotus follicularis, Drosophyllum lusitanicum, Drosera capensis, Dionaea muscipula, Aldrovanda vesiculosa, Genlisea violacea × lobata, Sarracenia psittacina and Sarracenia purpurea were stained with methylene blue in order to identify possible sites of uptake. The permeable parts of the traps were incubated with fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) and other fluorescent endocytosis markers, combined with the soluble protein BSA or respiratory inhibitors. Uptake was studied by confocal microscopy. In Nepenthes, small fluorescent vesicles became visible 1 h after incubation with FITC-BSA. These vesicles fused to larger compartments within 30 h. A similar behaviour was found in the related genera Drosera, Dionaea, Aldrovanda and Drosophyllum but also in Cephalotus with glands of different evolutionary origin. In Genlisea and Sarracenia, no evidence for endocytosis was found. We propose that in many carnivorous plants, nutrient uptake by carriers is supplemented by endocytosis, which enables absorption and intracellular digestion of whole proteins. The advantage for the plant of reducing secretion of enzymes for extracellular digestion is evident. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  13. The specific uptake size index for quantifying radiopharmaceutical uptake

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, John S [Department of Medical Physics and Bioengineering, Southampton University Hospitals NHS Trust, Southampton (United Kingdom); Bolt, Livia [Department of Medical Physics and Bioengineering, Southampton University Hospitals NHS Trust, Southampton (United Kingdom); Stratford, Jennifer S [Department of Medical Physics and Bioengineering, Southampton University Hospitals NHS Trust, Southampton (United Kingdom); Kemp, Paul M [Department of Nuclear Medicine, Southampton University Hospitals NHS Trust, Southampton (United Kingdom)

    2004-07-21

    Quantitative indices of radionuclide uptake in an object of interest provide a useful adjunct to qualitative interpretation in the diagnostic application of radionuclide imaging. This note describes a new measure of total uptake of an organ, the specific uptake size index (SUSI). It can either be related in absolute terms to the total activity injected or to the specific activity in a reference region. As it depends on the total activity in the object, the value obtained will not depend on the resolution of the imaging process, as is the case with some other similar quantitative indices. This has been demonstrated in an experiment using simulated images. The application of the index to quantification of dopamine receptor SPECT imaging and parathyroid-thyroid subtraction planar scintigraphy is described. The index is considered to be of potential value in reducing variation in quantitative assessment of uptake in objects with applications in all areas of radionuclide imaging. (note)

  14. Cellular uptake of metallated cobalamins

    DEFF Research Database (Denmark)

    Tran, Mai Thanh Quynh; Stürup, Stefan; Lambert, Ian Henry

    2016-01-01

    Cellular uptake of vitamin B12-cisplatin conjugates was estimated via detection of their metal constituents (Co, Pt, and Re) by inductively coupled plasma mass spectrometry (ICP-MS). Vitamin B12 (cyano-cob(iii)alamin) and aquo-cob(iii)alamin [Cbl-OH2](+), which differ in the β-axial ligands (CN......(-) and H2O, respectively), were included as control samples. The results indicated that B12 derivatives delivered cisplatin to both cellular cytosol and nuclei with an efficiency of one third compared to the uptake of free cisplatin cis-[Pt(II)Cl2(NH3)2]. In addition, uptake of charged B12 derivatives...

  15. Effect of the different 13-valent pneumococcal conjugate vaccination uptakes on the invasive pneumococcal disease in children: Analysis of a hospital-based and population-based surveillance study in Madrid, Spain, 2007-2015

    Science.gov (United States)

    Picazo, Juan; Ruiz-Contreras, Jesús; Casado-Flores, Juan; Negreira, Sagrario; Baquero, Fernando; Hernández-Sampelayo, Teresa; Otheo, Enrique; Méndez, Cristina

    2017-01-01

    In the Community of Madrid, the 13-valent pneumococcal conjugate vaccine (PCV13) replaced the 7-valent (PCV7) in the fully government-funded Regional Immunization Program (RIP) in May, 2010, but was later excluded in May, 2012, and included again in January, 2015. These unique changes allowed us to assess the impact of the different pneumococcal vaccination policies on PCV13 uptake in infants and on the incidence rate (IR) of invasive pneumococcal disease (IPD) in children <15 years old. In this prospective, active, surveillance study, we estimated PCV13 uptakes, IR and incidence rate ratios (IRR) for total IPD and for IPD caused by PCV13- and non-PCV13 serotypes in children <15 years, stratified by age, in four periods with different vaccination policies: fully government-funded PCV7 vaccination, fully government-funded PCV13, mixed public/private funding and only private funding. Vaccine uptakes reached 95% in periods with public-funded pneumococcal vaccination, but fell to 67% in the private funding period. Overall, IR of IPD decreased by 68% (p<0.001) in 2014–15, due to 93% reduction in the IR of PCV13-type IPD (p<0.001) without significant changes in non-PCV13-type IPD. A fully government-funded PCV13 vaccination program lead to high vaccine uptake and dramatic reductions in both overall and PCV13-type IPD IR. When this program was switched to private PCV13 vaccination, there was a fall in vaccine coverage and stagnation in the decline of PCV13-type IPD with data suggesting a weakening of herd immunity. PMID:28207888

  16. Matrix stiffness affects endocytic uptake of MK2-inhibitor peptides.

    Directory of Open Access Journals (Sweden)

    Jamie L Brugnano

    Full Text Available In this study, the role of substrate stiffness on the endocytic uptake of a cell-penetrating peptide was investigated. The cell-penetrating peptide, an inhibitor of mitogen-activated protein kinase activated protein kinase II (MK2, enters a primary mesothelial cell line predominantly through caveolae. Using tissue culture polystyrene and polyacrylamide gels of varying stiffness for cell culture, and flow cytometry quantification and enzyme-linked immunoassays (ELISA for uptake assays, we showed that the amount of uptake of the peptide is increased on soft substrates. Further, peptide uptake per cell increased at lower cell density. The improved uptake seen on soft substrates in vitro better correlates with in vivo functional studies where 10-100 µM concentrations of the MK2 inhibitor cell penetrating peptide demonstrated functional activity in several disease models. Additional characterization showed actin polymerization did not affect uptake, while microtubule polymerization had a profound effect on uptake. This work demonstrates that cell culture substrate stiffness can play a role in endocytic uptake, and may be an important consideration to improve correlations between in vitro and in vivo drug efficacy.

  17. Matrix stiffness affects endocytic uptake of MK2-inhibitor peptides.

    Science.gov (United States)

    Brugnano, Jamie L; Panitch, Alyssa

    2014-01-01

    In this study, the role of substrate stiffness on the endocytic uptake of a cell-penetrating peptide was investigated. The cell-penetrating peptide, an inhibitor of mitogen-activated protein kinase activated protein kinase II (MK2), enters a primary mesothelial cell line predominantly through caveolae. Using tissue culture polystyrene and polyacrylamide gels of varying stiffness for cell culture, and flow cytometry quantification and enzyme-linked immunoassays (ELISA) for uptake assays, we showed that the amount of uptake of the peptide is increased on soft substrates. Further, peptide uptake per cell increased at lower cell density. The improved uptake seen on soft substrates in vitro better correlates with in vivo functional studies where 10-100 µM concentrations of the MK2 inhibitor cell penetrating peptide demonstrated functional activity in several disease models. Additional characterization showed actin polymerization did not affect uptake, while microtubule polymerization had a profound effect on uptake. This work demonstrates that cell culture substrate stiffness can play a role in endocytic uptake, and may be an important consideration to improve correlations between in vitro and in vivo drug efficacy.

  18. Evidence for facilitated lactate uptake in lizard skeletal muscle.

    Science.gov (United States)

    Donovan, E R; Gleeson, T T

    2001-12-01

    To understand more fully lactate metabolism in reptilian muscle, lactate uptake in lizard skeletal muscle was measured and its similarities to the monocarboxylate transport system found in mammals were examined. At 2 min, uptake rates of 15 mmol l(-1) lactate into red iliofibularis (rIF) were 2.4- and 2.2-fold greater than white iliofibularis (wIF) and mouse soleus, respectively. alpha-Cyano-4-hydroxycinnamate (15 mmol l(-1)) caused little inhibition of uptake in wIF but caused a 42-54 % reduction in the uptake rate of lactate into rIF, suggesting that much of the lactate uptake by rIF is via protein-mediated transport. N-ethymaleimide (ETH) (10 mmol l(-1)) also caused a reduction in the rate of uptake, but measurements of adenylate and phosphocreatine concentrations show that ETH had serious effects on rIF and wIF and may not be appropriate for transport inhibition studies in reptiles. The higher net uptake rate by rIF than by wIF agrees with the fact that rIF shows much higher rates of lactate utilization and incorporation into glycogen than wIF. This study also suggests that lactate uptake by reptilian muscle is similar to that by mammalian muscle and that, evolutionarily, this transport system may be relatively conserved even in animals with very different patterns of lactate metabolism.

  19. Exercise training favors increased insulin-stimulated glucose uptake in skeletal muscle in contrast to adipose tissue: a randomized study using FDG PET imaging.

    Science.gov (United States)

    Reichkendler, M H; Auerbach, P; Rosenkilde, M; Christensen, A N; Holm, S; Petersen, M B; Lagerberg, A; Larsson, H B W; Rostrup, E; Mosbech, T H; Sjödin, A; Kjaer, A; Ploug, T; Hoejgaard, L; Stallknecht, B

    2013-08-15

    Physical exercise increases peripheral insulin sensitivity, but regional differences are poorly elucidated in humans. We investigated the effect of aerobic exercise training on insulin-stimulated glucose uptake in five individual femoral muscle groups and four different adipose tissue regions, using dynamic (femoral region) and static (abdominal region) 2-deoxy-2-[¹⁸F]fluoro-d-glucose (FDG) PET/CT methodology during steady-state insulin infusion (40 mU·m⁻²·min⁻¹). Body composition was measured by dual X-ray absorptiometry and MRI. Sixty-one healthy, sedentary [V(O2max) 36(5) ml·kg⁻¹·min⁻¹; mean(SD)], moderately overweight [BMI 28.1(1.8) kg/m²], young [age: 30(6) yr] men were randomized to sedentary living (CON; n = 17 completers) or moderate (MOD; 300 kcal/day, n = 18) or high (HIGH; 600 kcal/day, n = 18) dose physical exercise for 11 wk. At baseline, insulin-stimulated glucose uptake was highest in femoral skeletal muscle followed by intraperitoneal visceral adipose tissue (VAT), retroperitoneal VAT, abdominal (anterior + posterior) subcutaneous adipose tissue (SAT), and femoral SAT (P tissues). Metabolic rate of glucose increased similarly (~30%) in the two exercise groups in femoral skeletal muscle (MOD 24[9, 39] μmol·kg⁻¹·min⁻¹, P = 0.004; HIGH 22[9, 35] μmol·kg⁻¹·min⁻¹, P = 0.003) (mean[95% CI]) and in five individual femoral muscle groups but not in femoral SAT. Standardized uptake value of FDG decreased ~24% in anterior abdominal SAT and ~20% in posterior abdominal SAT compared with CON but not in either intra- or retroperitoneal VAT. Total adipose tissue mass decreased in both exercise groups, and the decrease was distributed equally among subcutaneous and intra-abdominal depots. In conclusion, aerobic exercise training increases insulin-stimulated glucose uptake in skeletal muscle but not in adipose tissue, which demonstrates some interregional differences.

  20. Rat L6 myotubes as an in vitro model system to study GLUT4-dependent glucose uptake stimulated by inositol derivatives

    OpenAIRE

    Yap, Angeline; Nishiumi, Shin; YOSHIDA, Ken-ichi; Ashida, Hitoshi

    2007-01-01

    Some of inositol derivatives have been reported to help the action of insulin stimulating glucose uptake in skeletal muscle cells. Rat L6 myotubes were employed in an attempt to develop an in vitro model system for investigation of the possible insulin-like effect of eight inositol derivatives, namely allo-inositol, d-chiro-inositol l-chiro-inositol, epi-inositol, muco-inositol, myo-inositol, scyllo-inositol and d-pinitol. At a higher concentration of 1 mM seven inositol derivatives other tha...

  1. Improving the uptake of systematic reviews: a systematic review of intervention effectiveness and relevance.

    LENUS (Irish Health Repository)

    Wallace, John

    2014-01-01

    Little is known about the barriers, facilitators and interventions that impact on systematic review uptake. The objective of this study was to identify how uptake of systematic reviews can be improved.

  2. Evaluating the Relationship between Equilibrium Passive Sampler Uptake and Aquatic Organism Bioaccumulation,

    Science.gov (United States)

    Objectives. This review evaluates passive sampler uptake of hydrophobic organic contaminants (HOCs) in water column and interstitial water exposures as a surrogate for organism bioaccumulation. Approach/Activities. Fifty-five studies were found where both passive sampler uptake...

  3. Water uptake and water supply

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    The water uptake and the water supply do not directly affect the mineral absorption of plants. However, many connections exist between the management of minerals and water. The most evident of those connections are following

  4. Octreotide Uptake in Parathyroid Adenoma

    Science.gov (United States)

    Karaçavuş, Seyhan; Kula, Mustafa; Cihan Karaca, Züleyha; Ünlühızarcı, Kürşad; Tutuş, Ahmet; Bayram, Fahri; Çoban, Ganime

    2012-01-01

    The patient with a history of bone pain and muscle weakness, was thought to have oncogenic osteomalacia as a result of biochemical investigations and directed to Nuclear Medicine Department for a whole-body bone scintigraphy and 111In-octreotide scintigraphy. There was no focal pathologic tracer uptake, but generalized marked increase in skeletal uptake on bone scintigraphy. Octreotide scintigraphy showed accumulation of octreotide in the region of the left lobe of the thyroid gland in the neck. Thereafter, parathyroid scintigraphy was performed with technetium-99m labeled metroxy-isobutyl-isonitryl (99mTc-MIB) and MIBI scan demonstrated radiotracer uptake at the same location with octreotide scintigraphy. The patient underwent left inferior parathyroidectomy and histopathology confirmed a parathyroid adenoma. Somatostatin receptor positive parathyroid adenoma may show octreotide uptake. Octreotide scintigraphy may be promising and indicate a possibility of using somatostatin analogues for the medical treatment of somatostatin receptor positive Conflict of interest:None declared. PMID:23487397

  5. Uptake of dehydroascorbic acid and ascorbic acid to isolated nerve terminals and secretory granules from ox neurohypophyses

    DEFF Research Database (Denmark)

    Thorn, N A; Nielsen, F S; Jeppesen, C K

    1986-01-01

    When uptake of L-[14C]ascorbic acid ([14C]AA) to various organs in guinea-pigs was studied after intracardiac injection, the adenohypophysis, pars intermedia, and the neurohypophysis had an uptake per milligramme protein which was about half of the uptake to the adrenals. Adrenal uptake was 20...

  6. Lung uptake of thallium-201: a marker of defect reversibility?

    Science.gov (United States)

    Sanderson, R.; Woldman, S.; McCurrach, G.; Martin, W.; Hutton, I.

    1998-06-01

    High lung uptake of thallium-201 at stress is reported to be associated with a large number of perfusion defects and poor prognosis. This study was performed to assess whether the reversibility of stress perfusion defects was related to lung uptake. Gated planar thallium scans at stress and at redistribution from 102 consecutive patients with essentially normal left ventricular ejection fraction (using gated blood pool ventriculography) were graded in terms of defect size. Lung and myocardial uptake of thallium were quantitated by region of interest methods relative to the given activity in a previously validated method. There was no significant correlation (non-parametric) between lung uptake and degree of redistribution (). There was a weak but positive correlation between lung uptake and defect size (). Both exercise time and double product showed a negative correlation with lung uptake (e.g. for double product, ). In conclusion, contrary to our expectation, lung uptake is not related to the degree of redistribution. High lung uptake seems to reflect poor cardiovascular reserve.

  7. Increased Brain Fatty Acid Uptake in Metabolic Syndrome

    Science.gov (United States)

    Karmi, Anna; Iozzo, Patricia; Viljanen, Antti; Hirvonen, Jussi; Fielding, Barbara A.; Virtanen, Kirsi; Oikonen, Vesa; Kemppainen, Jukka; Viljanen, Tapio; Guiducci, Letizia; Haaparanta-Solin, Merja; Någren, Kjell; Solin, Olof; Nuutila, Pirjo

    2010-01-01

    OBJECTIVE To test whether brain fatty acid uptake is enhanced in obese subjects with metabolic syndrome (MS) and whether weight reduction modifies it. RESEARCH DESIGN AND METHODS We measured brain fatty acid uptake in a group of 23 patients with MS and 7 age-matched healthy control subjects during fasting conditions using positron emission tomography (PET) with [11C]-palmitate and [18F]fluoro-6-thia-heptadecanoic acid ([18F]-FTHA). Sixteen MS subjects were restudied after 6 weeks of very low calorie diet intervention. RESULTS At baseline, brain global fatty acid uptake derived from [18F]-FTHA was 50% higher in patients with MS compared with control subjects. The mean percentage increment was 130% in the white matter, 47% in the gray matter, and uniform across brain regions. In the MS group, the nonoxidized fraction measured using [11C]-palmitate was 86% higher. Brain fatty acid uptake measured with [18F]-FTHA-PET was associated with age, fasting serum insulin, and homeostasis model assessment (HOMA) index. Both total and nonoxidized fractions of fatty acid uptake were associated with BMI. Rapid weight reduction decreased brain fatty acid uptake by 17%. CONCLUSIONS To our knowledge, this is the first study on humans to observe enhanced brain fatty acid uptake in patients with MS. Both fatty acid uptake and accumulation appear to be increased in MS patients and reversed by weight reduction. PMID:20566663

  8. Methionine Uptake and Required Radiation Dose to Control Glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Iuchi, Toshihiko, E-mail: tiuchi@chiba-cc.jp [Division of Neurological Surgery, Chiba Cancer Center, Chiba (Japan); Hatano, Kazuo [Division of Radiation Oncology, Tokyo Bay Advanced Imaging and Radiation Oncology Clinic, Makuhari, Chiba (Japan); Uchino, Yoshio [Division of Nuclear Medicine, Chiba Ryogo Center, Chiba (Japan); Itami, Makiko [Division of Surgical Pathology, Chiba Cancer Center, Chiba (Japan); Hasegawa, Yuzo; Kawasaki, Koichiro; Sakaida, Tsukasa [Division of Neurological Surgery, Chiba Cancer Center, Chiba (Japan); Hara, Ryusuke [Division of Radiation Oncology, Chiba Cancer Center, Chiba (Japan)

    2015-09-01

    Purpose: The purpose of this study was to retrospectively assess the feasibility of radiation therapy planning for glioblastoma multiforme (GBM) based on the use of methionine (MET) positron emission tomography (PET), and the correlation among MET uptake, radiation dose, and tumor control. Methods and Materials: Twenty-two patients with GBM who underwent MET-PET prior to radiation therapy were enrolled. MET uptake in 30 regions of interest (ROIs) from 22 GBMs, biologically effective doses (BEDs) for the ROIs and their ratios (MET uptake:BED) were compared in terms of whether the ROIs were controlled for >12 months. Results: MET uptake was significantly correlated with tumor control (odds ratio [OR], 10.0; P=.005); however, there was a higher level of correlation between MET uptake:BED ratio and tumor control (OR, 40.0; P<.0001). These data indicated that the required BEDs for controlling the ROIs could be predicted in terms of MET uptake; BED could be calculated as [34.0 × MET uptake] Gy from the optimal threshold of the MET uptake:BED ratio for tumor control. Conclusions: Target delineation based on MET-PET was demonstrated to be feasible for radiation therapy treatment planning. MET-PET could not only provide precise visualization of infiltrating tumor cells but also predict the required radiation doses to control target regions.

  9. Technique for measuring carbon monoxide uptake in mice

    Energy Technology Data Exchange (ETDEWEB)

    Depledge, M.H.; Collis, C.H.; Chir, B.; Barrett, A.

    1981-04-01

    A new method has been developed for measuring carbon monoxide (CO) uptake in mice. Each animal was placed in a syringe and allowed to rebreathe a mixture of CO and helium (He) for 60 s. CO uptake was detemined from a comparison of CO and He concentrations before and after rebreathing. Weight specific CO uptake increased with body weight in CBA mice weighing between 20 to 35 gr. In larger mice, size dependence was less marked, although a slight fall in CO uptake was observed in older animals. Anaesthesia reduced ventilatory rate and CO uptake to a variable extent. The method is reproducible, non-invasive and does not require anaesthesia; consequently, it can be used to study serial changes in lung function. It is sensitive enough to detect lung damage in CBA mice following 16 Gy total body irradiation. Values of diffusing capacity obtained for mice using this method are consistent with published values.

  10. Study of interaction of iron and lead during their uptake process in wheat roots by total-reflection X-ray fluorescence spectrometry

    Science.gov (United States)

    Varga, Anita; Záray, Gyula; Fodor, Ferenc; Cseh, Edit

    1997-07-01

    Microwave assisted acidic digestion and total-reflection X-ray fluorescence spectrometry (TXRF) was used for the determination of lead and iron in wheat roots cultured in CaSO 4 solution, and treated with Pb(NO 3) 2 and Fe(III)-citrate or Fe(III)-EDTA under controlled conditions, respectively. It was established that lead has a stimulation effect on the iron uptake in the presence of Fe(III)-citrate. The lead uptake, however, is hardly influenced by iron independently from the complex forming agents applied. To check the stability of the accumulated iron and lead constituents, some of the roots were washed with various solutions and the removable iron and lead were also measured by TXRF. These experiments indicate that the presence of lead results in higher stability of iron constituents in the root; however, iron does not have any effect on the lead constituents, the stabilities of which increase in the order Pb-citrate

  11. Differences of cardiac output measurements by open-circuit acetylene uptake in pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension: a cohort study

    Directory of Open Access Journals (Sweden)

    Schwaiblmair Martin

    2012-03-01

    Full Text Available Abstract Background As differences in gas exchange between pulmonary arterial hypertension (PAH and chronic thromboembolic pulmonary hypertension (CTEPH have been demonstrated, we asked if cardiac output measurements determined by acetylene (C2H2 uptake significantly differed in these diseases when compared to the thermodilution technique. Method Single-breath open-circuit C2H2 uptake, thermodilution, and cardiopulmonary exercise testing were performed in 72 PAH and 32 CTEPH patients. Results In PAH patients the results for cardiac output obtained by the two methods showed an acceptable agreement with a mean difference of -0.16 L/min (95% CI -2.64 to 2.32 L/min. In contrast, the agreement was poorer in the CTEPH group with the difference being -0.56 L/min (95% CI -4.96 to 3.84 L/min. Functional dead space ventilation (44.5 ± 1.6 vs. 32.2 ± 1.4%, p 2 gradient (9.9 ± 0.8 vs. 4.1 ± 0.5 mmHg, p Conclusion Cardiac output evaluation by the C2H2 technique should be interpreted with caution in CTEPH, as ventilation to perfusion mismatching might be more relevant than in PAH.

  12. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi-chun; WANG Guang-huo

    2005-01-01

    The ecosystem characteristics of soil microorganism and the nutrient uptake of irrigated rice were investigated in a split-block experiment with different fertilization treatments, including control (no fertilizer application), PK, NK, NP, NPK fertilization, in the main block, and conventional rice and hybrid rice comparison, in the sub block. Average data of five treatments in five years indicated that the indigenous N supply (INS) capacity ranged from 32.72 to 93.21 kg/ha; that indigenous P supply (IPS)capacity ranged from 7.42 to 32.25 kg/ha; and that indigenous K supply (IKS) capacity ranged from 16.24 to 140.51 kg/ha, which showed that soil available nutrient pool depletion might occur very fast and that P, K deficiency has become a constraint to increasing yields of consecutive crops grown without fertilizer application. It was found that soil nutrient deficiency and unbalanced fertilization to rice crop had negative effect on the diversity of the microbial community and total microbial biomass in the soil.The long-term fertilizer experiment (LTFE) also showed that balanced application of N, P and K promoted microbial biomass growth and improvement of community composition. Unbalanced fertilization reduced microbial N and increased C/N ratio of the microbial biomass. Compared with inbred rice, hybrid rice behavior is characterized by physiological advantage in nutrient uptake and lower internal K use efficiency.

  13. Differentiation of Glioblastomas from Metastatic Brain Tumors by Tryptophan Uptake and Kinetic Analysis: A Positron Emission Tomographic Study with Magnetic Resonance Imaging Comparison

    Directory of Open Access Journals (Sweden)

    David O. Kamson

    2013-07-01

    Full Text Available Differentiating high-grade gliomas from solitary brain metastases is often difficult by conventional magnetic resonance imaging (MRI; molecular imaging may facilitate such discrimination. We tested the accuracy of α[11C]methyl-L-tryptophan (AMT–positron emission tomography (PET to differentiate newly diagnosed glioblastomas from brain metastases. AMT-PET was performed in 36 adults with suspected brain malignancy. Tumoral AMT accumulation was measured by standardized uptake values (SUVs. Tracer kinetic analysis was also performed to separate tumoral net tryptophan transport (by AMT volume of distribution [VD] from unidirectional uptake rates using dynamic PET and blood input function. Differentiating the accuracy of these PET variables was evaluated and compared to conventional MRI. For glioblastoma/metastasis differentiation, tumoral AMT SUV showed the highest accuracy (74% and the tumor/cortex VD ratio had the highest positive predictive value (82%. The combined accuracy of MRI (size of contrast-enhancing lesion and AMT-PET reached up to 93%. For ring-enhancing lesions, tumor/cortex SUV ratios were higher in glioblastomas than in metastatic tumors and could differentiate these two tumor types with > 90% accuracy. These results demonstrate that evaluation of tryptophan accumulation by PET can enhance pretreatment differentiation of glioblastomas and metastatic brain tumors. This approach may be particularly useful in patients with a newly diagnosed solitary ring-enhancing mass.

  14. Multielemental fractionation in pine nuts (Pinus pinea) from different geographic origins by size-exclusion chromatography with UV and inductively coupled plasma mass spectrometry detection.

    Science.gov (United States)

    Gómez-Ariza, J L; Arias-Borrego, A; García-Barrera, T

    2006-07-21

    Pine nuts (Pinus pinea) from different geographical origin in Spain and Portugal have been investigated concerning total element content and metal-biomolecules size distribution patterns Mn, Zn, Ni and Cu. All the studied metals were at the highest concentration in pine nuts from Faro and at the lowest from Cataluña. The most abundant element in samples was Mn at concentrations in the range of 26 microg g(-1) (Cataluña) to 559 microg g(-1) (Faro). Zn was also present at high concentration in samples, from 25 microg g(-1) (Cataluña) to 113 microg g(-1) (Faro). To a deeper insight to obtain classification rules for samples, pine nuts were analyzed by size-exclusion chromatography (SEC) with UV detection and inductively coupled plasma mass spectrometry (ICP-MS). Two columns were used covering the molecular weigh range from pine nuts from Huelva. This column allows good discrimination in the range of 2126-1352 Da in which a lot of peaks can be used to differentiate samples. The UV profiles obtained with the high molecular weight (HMW) column allows a poorer differentiation of samples, but pine nuts from Huelva, Castilla and Madrid are clearly distinguished to the others. In relation to fractionation patterns of metals, Mn allows a good discrimination between samples (LMW column), Cu was the only one associated to fractions at MW > 70 kDa in sample from Cádiz, and profiles of Ni and Zn are clearly different in terms of abundance of peaks. All these chromatographic profiles for elements give valuable information about the geographical origin of the studied samples and the differences found are discussed in this work.

  15. Multi-elemental characterization of organic liquid samples by use of a 13 MeV {sup 6}Li{sup 3+} beam

    Energy Technology Data Exchange (ETDEWEB)

    Liendo, J.A., E-mail: jliendo@usb.v [Department of Physics, Simon Bolivar University, PO Box 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of); Bernal, M.A., E-mail: mbernal@usb.v [Department of Physics, Simon Bolivar University, PO Box 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of); Gonzalez, A.C. [Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Caracas (Venezuela, Bolivarian Republic of); Caussyn, D.D.; Fletcher, N.R.; Momotyuk, O.A. [Department of Physics, Florida State University, Tallahassee (United States); Muruganathan, R.M. [Department of Chemistry, Florida State University, Tallahassee (United States); Roeder, B.T.; Wiedenhoever, I. [Department of Physics, Florida State University, Tallahassee (United States); Fischer, T. [Department of Chemistry, Florida State University, Tallahassee (United States); Kemper, K.W.; Barber, P. [Department of Physics, Florida State University, Tallahassee (United States); Sajo-Bohus, L. [Department of Physics, Simon Bolivar University, PO Box 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of)

    2009-10-15

    Evaporated amniotic fluid (AF) targets have been bombarded with a 13 MeV {sup 6}Li{sup 3+} beam. Forward angle data have served to identify the {sup 1}H({sup 6}Li,{sup 1}H){sup 6}Li reaction as an alternative for hydrogen characterization of such organic samples. Detected {sup 6}Li ions elastically scattered from C, N, O, Na and Cl can also be used to determine the concentrations of these elements in AF. The analyzed AF samples have been diluted with distilled water. The effect of sample dilution on the improvement of spectrum energy resolution has been observed, confirming previous reports. The hydrogen concentration determined in the studied AF targets is shown to vary linearly with sample dilution. Two detector arrangements have been used to find out which detection scheme is the most convenient. The combination of a counter telescope and a single detector, set up at the same polar angle on the opposite side of the beam, seems to be the best choice to have a reliable particle identification and an adequate energy resolution simultaneously.

  16. Micro- and nano-environments of C sequestration in soil: a multi-elemental STXM-NEXAFS assessment of black C and organomineral associations.

    Science.gov (United States)

    Solomon, Dawit; Lehmann, Johannes; Wang, Jian; Kinyangi, James; Heymann, Karen; Lu, Yingshen; Wirick, Sue; Jacobsen, Chris

    2012-11-01

    Black C is an essential component of the terrestrial C pool and its formation is often credited as a CO(2) sink by transferring the fast-cycling C from the atmosphere-biosphere system into slower cycling C in the geosphere. This study is the first multi-element K- (C, N, Ca, Fe, Al and Si) soft-X-ray STXM-NEXAFS investigation conducted at a submicron-scale spatial resolution specifically targeting black C and its interaction with the mineral and non-black C organic matter in the organomineral assemblage. The STXM-NEXAFS micrographs and spectra demonstrated that pyrogenic C was dominated by quinoide, aromatic, phenol, ketone, alcohol, carboxylic and hydroxylated- and ether-linked C species. There was also evidence for the presence of pyridinic, pyridonic, pyrrolic, amine and nitril N functionalities. The non-black C organic matter contained amino acids, amino sugars, nucleic acids and polysaccharides known to exhibit negatively charged carboxylic, phenolic, enolic, thiolate and phosphate functionalities highly reactive towards metal ions and black C. The metal-rich mineral matrix was composed of phyllosilicate clay minerals, Fe and Al hydroxypolycations, oxides, hydroxides and oxyhydroxide that can attract and bind organic biopolymers. STXM-NEXAFS provided evidence for interactive association between pyrogenic C, non-black C organic matter and the mineral oxide and oxyhydroxide communities in the organomineral interface. These intimate associations occurred through a "two-way" direct linkage between black C and the mineral or non-black C organic matter or via a "three-way" indirect association where non-black C organic matter could serve as a molecular cross-linking agent binding black C with the mineral matrix or vice versa where inorganic oxides, hydroxides and polycations could act as a bridge to bind black C with non-black C organic matter. The binding and sequestration of black C in the investigated micro- and nano-C repository environments seem to be the

  17. Mechanisms of Ocean Heat Uptake

    Science.gov (United States)

    Garuba, Oluwayemi

    An important parameter for the climate response to increased greenhouse gases or other radiative forcing is the speed at which heat anomalies propagate downward in the ocean. Ocean heat uptake occurs through passive advection/diffusion of surface heat anomalies and through the redistribution of existing temperature gradients due to circulation changes. Atlantic meridional overturning circulation (AMOC) weakens in a warming climate and this should slow the downward heat advection (compared to a case in which the circulation is unchanged). However, weakening AMOC also causes a deep warming through the redistributive effect, thus increasing the downward rate of heat propagation compared to unchanging circulation. Total heat uptake depends on the combined effect of these two mechanisms. Passive tracers in a perturbed CO2 quadrupling experiments are used to investigate the effect of passive advection and redistribution of temperature anomalies. A new passive tracer formulation is used to separate ocean heat uptake into contributions due to redistribution and passive advection-diffusion of surface heating during an ocean model experiment with abrupt increase in surface temperature. The spatial pattern and mechanisms of each component are examined. With further experiments, the effects of surface wind, salinity and temperature changes in changing circulation and the resulting effect on redistribution in the individual basins are isolated. Analysis of the passive advection and propagation path of the tracer show that the Southern ocean dominates heat uptake, largely through vertical and horizontal diffusion. Vertical diffusion transports the tracer across isopycnals down to about 1000m in 100 years in the Southern ocean. Advection is more important in the subtropical cells and in the Atlantic high latitudes, both with a short time scale of about 20 years. The shallow subtropical cells transport the tracer down to about 500m along isopycnal surfaces, below this vertical

  18. Maximum oxygen uptake and objectively measured physical activity in Danish children 6-7 years of age: the Copenhagen school child intervention study

    DEFF Research Database (Denmark)

    Eiberg, Stig; Hasselstrøm, Henriette; Grønfeldt, Vivian

    2005-01-01

    preschool classes in two suburban communities in Copenhagen, during a progressive treadmill exercise. Habitual physical activity was measured with accelerometers. Results: Boys had higher VO2MAX both in absolute values (1.19 (0.18) v 1.06 (0.16) litres/min (+11%), p... +9.4%, pactive. The difference in physical activity between the sexes was higher when sustained activity of higher intensity was compared. Conclusions: VO2MAX is higher in boys than girls (+11%), even when......Objectives: To provide normative data on maximum oxygen uptake (V·O2MAX) and physical activity in children 6-7 years of age and analyse the association between these variables. Methods: VO2MAX was measured in 366 boys (mean (SD) 6.8 (0.4) years of age) and 332 girls (6.7 (0.4) years of age) from...

  19. Exercise training favors increased insulin-stimulated glucose uptake in skeletal muscle in contrast to adipose tissue: a randomized study using FDG PET imaging

    DEFF Research Database (Denmark)

    Reichkendler, M. H.; Auerbach, P.; Rosenkilde, M.

    2013-01-01

    Physical exercise increases peripheral insulin sensitivity, but regional differences are poorly elucidated in humans. We investigated the effect of aerobic exercise training on insulin-stimulated glucose uptake in five individual femoral muscle groups and four different adipose tissue regions...... abdominal SAT compared with CON but not in either intra- or retroperitoneal VAT. Total adipose tissue mass decreased in both exercise groups, and the decrease was distributed equally among subcutaneous and intra-abdominal depots. In conclusion, aerobic exercise training increases insulin-stimulated glucose...... was highest in femoral skeletal muscle followed by intraperitoneal visceral adipose tissue (VAT), retroperitoneal VAT, abdominal (anterior + posterior) subcutaneous adipose tissue (SAT), and femoral SAT (P tissues). Metabolic rate of glucose increased similarly (∼30%) in the two exercise...

  20. Uptake and bio-reactivity of polystyrene nanoparticles is affected by surface modifications, ageing and LPS adsorption: in vitro studies on neural tissue cells

    Science.gov (United States)

    Murali, Kumarasamy; Kenesei, Kata; Li, Yang; Demeter, Kornél; Környei, Zsuzsanna; Madarász, Emilia

    2015-02-01

    Because of their capacity of crossing an intact blood-brain barrier and reaching the brain through an injured barrier or via the nasal epithelium, nanoparticles have been considered as vehicles to deliver drugs and as contrast materials for brain imaging. The potential neurotoxicity of nanoparticles, however, is not fully explored. Using particles with a biologically inert polystyrene core material, we investigated the role of the chemical composition of particle surfaces in the in vitro interaction with different neural cell types. PS NPs within a size-range of 45-70 nm influenced the metabolic activity of cells depending on the cell-type, but caused toxicity only at extremely high particle concentrations. Neurons did not internalize particles, while microglial cells ingested a large amount of carboxylated but almost no PEGylated NPs. PEGylation reduced the protein adsorption, toxicity and cellular uptake of NPs. After storage (shelf-life >6 months), the toxicity and cellular uptake of NPs increased. The altered biological activity of ``aged'' NPs was due to particle aggregation and due to the adsorption of bioactive compounds on NP surfaces. Aggregation by increasing the size and sedimentation velocity of NPs results in increased cell-targeted NP doses. The ready endotoxin adsorption which cannot be prevented by PEG coating, can render the particles toxic. The age-dependent changes in otherwise harmless NPs could be the important sources for variability in the effects of NPs, and could explain the contradictory data obtained with ``identical'' NPs.Because of their capacity of crossing an intact blood-brain barrier and reaching the brain through an injured barrier or via the nasal epithelium, nanoparticles have been considered as vehicles to deliver drugs and as contrast materials for brain imaging. The potential neurotoxicity of nanoparticles, however, is not fully explored. Using particles with a biologically inert polystyrene core material, we investigated the

  1. Poor Tc-99m dimercaptosuccinic acid uptake, re-evaluation with Tc-99m MAG3 scintigraphy in Lowe syndrome

    OpenAIRE

    Koca, Gokhan; Atilgan, Hasan Ikbal; Demirel, Koray; Diri, Akif; KORKMAZ, Meliha

    2011-01-01

    Tc-99m dimercaptosuccinic acid (DMSA) is filtered through the glomeruli and reabsorbed by the proximal tubules as low molecular weight proteins. In Lowe syndrome this mechanism is impaired and so poor DMSA uptake is seen. Poor DMSA uptake was shown in very few studies, but none mentioned normal Tc-99m MAG3 uptake. In this case, the patient had poor DMSA uptake, normal MAG3 uptake and a neurogenic bladder in anterior to the left kidney that attenuates left kidney.

  2. Factors Contributing to Low Uptake of Cervical Screening in a ...

    African Journals Online (AJOL)

    Results: About 212 (78.2%) of the respondents have heard about cancer ... Discussion: The respondents in this study have demonstrated a high level of awareness of cervical cancer but low uptake of cervical cancer screening ... Article Metrics.

  3. Adjusting ammonium uptake via phosphorylation.

    Science.gov (United States)

    Lanquar, Viviane; Frommer, Wolf B

    2010-06-01

    In plants, AMT/MEP/Rh superfamily mediates high affinity ammonium uptake. AMT/MEP transporters form a trimeric complex, which requires a productive interaction between subunits in order to be functional. The AMT/MEP C-terminal domain is highly conserved in more than 700 AMT homologs from cyanobacteria to higher plants with no cases found to be lacking this domain. AMT1;1 exists in active and inactive states, probably controlled by the spatial positioning of the C-terminus. Ammonium triggers the phosphorylation of a conserved threonine residue (T460) in the C-terminus of AMT1;1 in a time- and concentration-dependent manner. The T460 phosphorylation level correlates with a decrease of root ammonium uptake. We propose that ammonium-induced phosphorylation modulates ammonium uptake as a general mechanism to protect against ammonium toxicity.

  4. Astaxanthin uptake in domestic dogs and cats

    Directory of Open Access Journals (Sweden)

    Massimino Stefan

    2010-06-01

    Full Text Available Abstract Background Research on the uptake and transport of astaxanthin is lacking in most species. We studied the uptake of astaxanthin by plasma, lipoproteins and leukocytes in domestic dogs and cats. Methods Mature female Beagle dogs (18 to 19 mo old; 11 to 14 kg BW were dosed orally with 0, 0.1, 0.5, 2.5, 10 or 40 mg astaxanthin and blood taken at 0, 3, 6, 9, 12, 18 and 24 h post-administration (n = 8/treatment. Similarly, mature domestic short hair cats (12 mo old; 3 to 3.5 kg body weight were fed a single dose of 0, 0.02, 0.08, 0.4, 2, 5, or 10 mg astaxanthin and blood taken (n = 8/treatment at the same interval. Results Both dogs and cats showed similar biokinetic profiles. Maximal astaxanthin concentration in plasma was approximately 0.14 μmol/L in both species, and was observed at 6 h post-dosing. The plasma astaxanthin elimination half-life was 9 to 18 h. Astaxanthin was still detectable by 24 h in both species. In a subsequent study, dogs and cats were fed similar doses of astaxanthin daily for 15 to 16 d and astaxanthin uptake by plasma, lipoproteins, and leukocytes studied. In both species, plasma astaxanthin concentrations generally continued to increase through d 15 or 16 of supplementation. The astaxanthin was mainly associated with high density lipoprotein (HDL. In blood leukocytes, approximately half of the total astaxanthin was found in the mitochondria, with significant amounts also associated with the microsomes and nuclei. Conclusion Dogs and cats absorb astaxanthin from the diet. In the blood, the astaxanthin is mainly associated with HDL, and is taken up by blood leukocytes, where it is distributed to all subcellular organelles. Certain aspects of the biokinetic uptake of astaxanthin in dogs and cats are similar to that in humans.

  5. Lactate, Glucose and Oxygen Uptake in Human Brain During Recovery from Maximal Exercise

    DEFF Research Database (Denmark)

    Kojiro, I.; Schmalbruch, I.K.; Quistorff, B.

    1999-01-01

    Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake......Skeletal muscle, brain lactate uptake, brain oxygen uptake, energy metabolism, brain glucose uptake...

  6. Explaining variation in the uptake of HPV vaccination in England

    Directory of Open Access Journals (Sweden)

    Whynes David K

    2011-03-01

    intentions surveys and pilot studies. Deprivation, the ethnic composition of the population, the effectiveness of primary care and the acceptability of childhood vaccinations are salient factors in explaining local HPV vaccine uptake in England.

  7. Ensemble learned vaccination uptake prediction using web search queries

    DEFF Research Database (Denmark)

    Hansen, Niels Dalum; Lioma, Christina; Mølbak, Kåre

    2016-01-01

    We present a method that uses ensemble learning to combine clinical and web-mined time-series data in order to predict future vaccination uptake. The clinical data is official vaccination registries, and the web data is query frequencies collected from Google Trends. Experiments with official...... vaccine records show that our method predicts vaccination uptake eff?ectively (4.7 Root Mean Squared Error). Whereas performance is best when combining clinical and web data, using solely web data yields comparative performance. To our knowledge, this is the ?first study to predict vaccination uptake...

  8. Serial changes in BMIPP uptake in relation to thallium uptake in the rat myocardium after ischaemia

    Energy Technology Data Exchange (ETDEWEB)

    Noriyasu, Kazuyuki; Tsukamoto, Takahiro; Kohya, Tetsuro; Kitabatake, Akira [Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Mabuchi, Megumi; Morita, Koichi; Tamaki, Nagara [Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, N-15, W-7, Kita-Ku, 060-8638 Sapporo (Japan); Kuge, Yuji [Department of Tracer Kinetics, Hokkaido University Graduate School of Medicine, Sapporo (Japan)

    2003-12-01

    Several clinical studies have shown that iodine-123 labelled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) uptake is often lower than the uptake of perfusion tracers in patients with ischaemic heart disease. However, BMIPP accumulation may not decrease during the acute phase of a stunned myocardium in patients with acute coronary syndrome. We evaluated serial changes in BMIPP and perfusion tracer uptake in the myocardium after ischaemia. We performed a 20-min left coronary artery occlusion followed by reperfusion in male Wister rats. One hour after the reperfusion, echocardiography was performed. Intravenous injection of iodine-125 labelled BMIPP and thallium-201 was performed 1 day (acute group) and 5 days (subacute group) after the operation. To determine the myocardial distribution of {sup 125}I-BMIPP and {sup 201}Tl, dual-tracer autoradiography was conducted. We identified regions of interest in the anterolateral wall as an area at risk and in the inferoseptum as a remote control area. The anterolateral wall/inferoseptum ratio (A/I ratio) was calculated to compare the distributions of {sup 125}I-BMIPP and {sup 201}Tl. Coronary occlusion induced hypokinesia in the anterolateral region 1 h after the reperfusion. The A/I ratio of {sup 125}I-BMIPP was significantly higher than that of {sup 201}Tl in the acute group (1.01{+-}0.15 vs 0.80{+-}0.23, P<0.001). On the other hand, there was no significant difference between the A/I ratios of {sup 125}I-BMIPP and {sup 201}Tl in the subacute group (0.88{+-}0.18 vs 0.85{+-}0.18). Two rats showed a significantly lower A/I ratio of {sup 125}I-BMIPP than {sup 201}Tl in the subacute phase. These data suggest that BMIPP uptake is preserved despite a decrease in perfusion in the acute phase after ischaemia. In the subacute phase, on the other hand, BMIPP uptake is similar to or even lower than thallium uptake. Since BMIPP uptake may change with time after ischaemia, careful interpretation of BMIPP uptake after

  9. Low uptake affinity cultivars with biochar to tackle Cd-tainted rice — A field study over four rice seasons in Hunan, China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, De; Guo, Hu; Li, Ruiyue [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Li, Lianqing, E-mail: lqli@njau.edu.cn [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Pan, Genxing [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); Chang, Andrew [Department of Environmental Sciences, University of California, Riverside, CA 92521 (United States); Joseph, Stephen [Institute of Resources, Ecosystem and Environment of Agriculture, and Center of Biochar and Green Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing 210095 (China); School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052 (Australia)

    2016-01-15

    Biochar is becoming an environmentally friendly material for remediation of heavy metal contaminated soils and improving food safety. A field trial over four rice seasons was conducted to investigate the use of biochar and low Cd accumulating cultivars on Cd uptake in a heavy metal contaminated soil. Wheat straw derived biochar was applied at 0, 20 and 40 t ha{sup −1}. Two rice cultivars with differing Cd accumulation abilities were selected in each season. The results showed that both biochar and low Cd affinity cultivars significantly reduced rice grain Cd accumulation. Biochar had no significant effect the first season but thereafter consistently reduced rice grain Cd by a maximum of 61, 86 and 57% over the next three seasons. Zn accumulation in the rice grains was not decreased by biochar application, although available soil Zn was sharply reduced (35–91%). Indica conventional rice cultivars had much lower Cd, but higher Zn and lower Cd/Zn ratios in the grain than indica hybrid cultivars. Biochar was more effective for mitigating grain Cd accumulation in low Cd affinity cultivars than in high affinity cultivars. Soil pH was sustainably increased (up to nearly 1 unit) while available Cd significantly decreased by a maximum of 85% after biochar addition. The translocation of Cd from rice roots to shoots was reduced from 20 to 80% by biochar. Low uptake affinity cultivars combined with biochar reduced late rice grain Cd concentration and Cd/Zn ratios by 69–80% and 72–80%, respectively. It indicated that the management of combining biochar and low Cd affinity cultivars should be an efficient way to remediate Cd contaminated rice paddies and reduce health risk associated with consuming rice from these soils. - Highlights: • Biochar sustainably reduced soil Cd availability and Cd translocation in rice plant. • Indica conventional cultivars had lower Cd but higher Zn in grains than hybrid ones. • Biochar significantly reduced grain Cd and Cd/Zn ratio

  10. Quantitative fluorescence imaging reveals point of release for lipoproteins during LDLR-dependent uptake[S

    Science.gov (United States)

    Pompey, Shanica; Zhao, Zhenze; Luby-Phelps, Kate; Michaely, Peter

    2013-01-01

    The LDL receptor (LDLR) supports efficient uptake of both LDL and VLDL remnants by binding lipoprotein at the cell surface, internalizing lipoprotein through coated pits, and releasing lipoprotein in endocytic compartments before returning to the surface for further rounds of uptake. While many aspects of lipoprotein binding and receptor entry are well understood, it is less clear where, when, and how the LDLR releases lipoprotein. To address these questions, the current study employed quantitative fluorescence imaging to visualize the uptake and endosomal processing of LDL and the VLDL remnant β-VLDL. We find that lipoprotein release is rapid, with most release occurring prior to entry of lipoprotein into early endosomes. Published biochemical studies have identified two mechanisms of lipoprotein release: one that involves the β-propeller module of the LDLR and a second that is independent of this module. Quantitative imaging comparing uptake supported by the normal LDLR or by an LDLR variant incapable of β-propeller-dependent release shows that the β-propeller-independent process is sufficient for release for both lipoproteins but that the β-propeller process accelerates both LDL and β-VLDL release. Together these findings define where, when, and how lipoprotein release occurs and provide a generalizable methodology for visualizing endocytic handling in situ. PMID:23296879

  11. Intestinal uptake of bone seeking radiotracer: possible mechanisms and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D. W.; Kim, C. G.; Park, S. A.; Chang, J. A. [WonKwang University Hospital, Iksan (Korea, Republic of)

    2007-07-01

    This study was undertaken to investigate the frequency of intestinal accumulation of Tc-99m 3, 3-diphosphono-1, 2-propanedicarboxylic acid (DPD) on bone scans, describe the patterns of intestinal Tc-99m DPD uptake and discuss the possible mechanisms of this unusual finding. Three thousand, one hundred and ninety-four consecutive patients have been evaluated for intestinal Tc-99m DPD uptake on bone scans. A whole-body bone scan and various spot views were obtained to evaluate the location and intensity of intestinal uptake. Delayed scan and SPECT study were performed to define characteristics of intestinal uptake in some of patients. Available reports of co-relative radiologic imaging, endoscopic studies and laboratory tests were also reviewed to explain the intestinal uptake. Eighteen (9 female, 9 male) patients out of 3194 with a mean age of 57 years showed intestinal Tc-99m DPD uptake. The locations of intestinal uptake were well dispersed throughout the abdomen. The majority of the cases showed lower intensity than iliac spine (12/18, 67%). Eight patients didn't show significant change of uptake characteristics on the delayed images, while intestinal uptake traveled distally in nine patients. Two cases were revealed uptake of peritoneal carcinomatosis with small amount ascites and three cases were revealed tumoral uptake of intestine. Four patients with gastritis showed similar characteristic of intestinal uptake. Six cases of distally traveled intestinal uptake suggested intraluminal Tc-99m DPD activity such as gastrointestinal bleeding. However, stool occult blood tests were negative in three patients, and there is no clinical evidence of gastrointestinal bleeding in other three patients. Intestinal Tc-99m DPD uptake can be observed in 0.5% of bone scans. The mechanism of intestinal uptake is still unclear in some of the patients. Delayed imaging additional spot views and SPECT studies help in the differentiation of this finding from possible

  12. Vesicular uptake of macromolecules by human placental amniotic epithelial cells.

    Science.gov (United States)

    Sharshiner, Rita; Brace, Robert A; Cheung, Cecilia Y

    2017-09-01

    Studies in animal models have shown that unidirectional vesicular transport of amniotic fluid across the amnion plays a primary role in regulating amniotic fluid volume. Our objective was to explore vesicle type, vesicular uptake and intracellular distribution of vesicles in human amnion cells using high- and super-resolution fluorescence microscopy. Placental amnion was obtained at cesarean section and amnion cells were prepared and cultured. At 20%-50% confluence, the cells were incubated with fluorophore conjugated macromolecules for 1-30 min at 22 °C or 37 °C. Fluorophore labeled macromolecules were selected as markers of receptor-mediated caveolar and clathrin-coated vesicular uptake as well as non-specific endocytosis. After fluorophore treatment, the cells were fixed, imaged and vesicles counted using Imaris(®) software. Vesicular uptake displayed first order saturation kinetics with half saturation times averaging 1.3 min at 37 °C compared to 4.9 min at 22 °C, with non-specific endocytotic uptake being more rapid at both temperatures. There was extensive cell-to-cell variability in uptake rate. Under super-resolution microscopy, the pattern of intracellular spatial distribution was distinct for each macromolecule. Co-localization of fluorescently labeled macromolecules was very low at vesicular dimensions. In human placental amnion cells, 1) vesicular uptake of macromolecules is rapid, consistent with the concept that vesicular transcytosis across the amnion plays a role in the regulation of amniotic fluid volume; 2) uptake is temperature dependent and variable among individual cells; 3) the unique intracellular distributions suggest distinct functions for each vesicle type; 4) non-receptor mediated vesicular uptake may be a primary vesicular uptake mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Tumor uptake of radioruthenium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S C; Richards, P; Meinken, G E; Larson, S M; Grunbaum, Z

    1980-01-01

    The use of ruthenium-97 as a scintigraphic agent, particularly for tumor localization, is investigated. The tumor uptake of ruthenium chloride and ruthenium-labelled transferrin is evaluated and their application as tumor-imagine agents is compared to gallium-67 citrate. (ACR)

  14. Prostatic uptake of Ga-67

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, W.T.; Rosen, P.R.; Weiland, F.L.; Ritchey, M.L.

    1984-08-01

    Midline activity low in the pelvis seen on Ga-67 scans is frequently attributed to colonic excretion of radionuclide. Two cases of infectious prostatitis with focal uptake of Ga-67 within the prostate gland are described. A technique of using limited quantities of barium administered by enema and appropriate positional imaging, which localized pelvic activity to the prostate, is described.

  15. Octreotide Uptake in Parathyroid Adenoma

    Directory of Open Access Journals (Sweden)

    Seyhan Karaçavuş

    2012-08-01

    Full Text Available The patient with a history of bone pain and muscle weakness, was thought to have oncogenic osteomalacia as a result of biochemical investigations and directed to Nuclear Medicine Department for a whole-body bone scintigraphy and 111In-octreotide scintigraphy. There was no focal pathologic tracer uptake, but generalized marked increase in skeletal uptake on bone scintigraphy. Octreotide scintigraphy showed accumulation of octreotide in the region of the left lobe of the thyroid gland in the neck. Thereafter, parathyroid scintigraphy was performed with technetium-99m labeled metroxy-isobutyl-isonitryl (99mTc-MIB and MIBI scan demonstrated radiotracer uptake at the same location with octreotide scintigraphy. The patient underwent left inferior parathyroidectomy and histopathology confirmed a parathyroid adenoma. Somatostatin receptor positive parathyroid adenoma may show octreotide uptake. Octreotide scintigraphy may be promising and indicate a possibility of using somatostatin analogues for the medical treatment of somatostatin receptor positive parathyroid tumors. (MIRT 2012;21:77-79

  16. Cellular uptake of metallated cobalamins

    DEFF Research Database (Denmark)

    Tran, MQT; Stürup, Stefan; Lambert, Ian H.;

    2016-01-01

    Cellular uptake of vitamin B12-cisplatin conjugates was estimated via detection of their metal constituents (Co, Pt, and Re) by inductively coupled plasma mass spectrometry (ICP-MS). Vitamin B12 (cyano-cob(iii)alamin) and aquo-cob(iii)alamin [Cbl-OH2](+), which differ in the β-axial ligands (CN(-...

  17. Influence of drugs on myocardial iodine-123 metaiodobenzylguanidine uptake in rabbit myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, S.; Karanikas, G.; Rodrigues, M.; Sinzinger, H. [Dept. of Nuclear Medicine, University of Vienna (Austria)

    2000-03-01

    About 15 years ago, iodine-123 metaiodobenzylguanidine (MIBG) myocardial imaging was introduced for the evaluation of myocardial sympathetic nerve function. Two uptake mechanisms for MIBG have so far been identified: uptake type I, a saturable, energy-dependent mechanism, and uptake type II, a non-saturable, energy-independent mechanism. We incubated isolated rabbit myocardial tissue samples with{sup 123}I-MIBG in order to assess the uptake characteristics and the influence of varying incubation conditions. Furthermore, we examined the effects of several drugs and uptake inhibitors on the myocardial uptake of MIBG. The in vitro myocardial uptake of MIBG reached a steady plateau at 23.87%{+-}3.63% after 1 h, i.e. a concentration gradient of 10, in a thermo-independent manner within a concentration range from 1.5 to 1500 {mu}M. This indicates an unsaturable uptake process in the tested concentrations. Pre-incubation with the following drugs caused a significant inhibitory effect on myocardial MIBG uptake: haloperidol, levomepromazine, metoprolol, labetalol and clomipramine. According to our findings, the uptake mechanism seems to be an unspecific process, but the concentration gradient of 10 makes passive diffusion unlikely. Further studies with uptake-II-blocking substances as well as with isolated myocardial cells will be needed to clarify the nature of the myocardial MIBG uptake mechanism. (orig.)

  18. Uptake and retention of amitriptyline by kaolinite.

    Science.gov (United States)

    Lv, Guocheng; Stockwell, Christie; Niles, Jacqueline; Minegar, Skylar; Li, Zhaohui; Jiang, Wei-Teh

    2013-12-01

    As the most commonly prescribed tricyclic antidepressant, amitriptyline (AT) is frequently detected in wastewater, surface runoff, and effluents from sewage treatment plants, and could potentially reach agriculture land through the application of municipal biosolids or reclaimed water. Kaolinite is one of the most important soil components under warm and humid climate conditions. In this study, the uptake and retention of AT by kaolinite from aqueous solution were investigated by batch tests, XRD, and FTIR analyses. The uptake of AT on kaolinite was instantaneous, attributed to surface adsorption as confirmed by XRD analyses. Quantitative correlation between desorption of exchangeable cations and AT adsorption confirmed experimentally that cation exchange was the dominant mechanism of AT uptake on kaolinite. The values for free energy of adsorption also suggested physi-sorption such as cation exchange. Solution pH had minimal influence at pH 5-11 even though the pKa value of AT was 9.4 and the surface charge of kaolinite was pH-dependent. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Pulmonary uptake of morphine (M)

    Energy Technology Data Exchange (ETDEWEB)

    Roerig, D.L.; Bunke, S.S.; Kotrly, K.J.; Dawson, C.A.; Kampine, J.P.

    1986-03-01

    Previously the authors reported less than 5% of M was taken up during the first pass through the human lung. The low uptake of this basic lipophilic amine was further investigated in a single pass isolated perfused rat lung (IPL) in comparison to uptake of radiolabelled H/sub 2/O, antipyrine (A), aminopyrine (AM), nicotine (N) and phenylethylamine (P). The IPL was perfused for 5 min with each drug (5nmol/ml) and effluent collected in 10 sec fractions. Pulmonary extraction was calculated using indocyanine green dye as a non-extractable reference indicator. Accumulation of all compounds in the IPL reached an apparent equilibrium within 4 min. At equilibrium lung/perfusate conc. ratios for H/sub 2/O, A, AM, N, P and M were 1.04, 0.84, 0.85, 1.44, 2.57 and 1.13 respectively. The time course of M uptake differed from the other compounds since initial extraction of M was low (23%) compared to 75%, 53%, 35%, 82% and 86% for H/sub 2/O, A, AM, N and P respectively. Also, the half time to equilibrium for M was longer (50 sec) compared to 18, 21, 26, 19 and 22 sec for H/sub 2/O, A, AM, N and P respectively. The low initial pulmonary extraction of M compared to these compounds followed by greater M extraction during the remainder of drug infusion suggests uptake mechanisms for M different than the flow limited uptake for water and other basic amine drugs.

  20. Quantification of radionuclide uptake levels for primary bone tumors

    Directory of Open Access Journals (Sweden)

    Hasford Francis

    2015-04-01

    Full Text Available The purpose of the study is to quantify the level of uptake of administered radionuclide in primary bone tumors for patients undergoing bone scintigraphy. Retrospective study on 48 patient's scintigrams to quantify the uptake levels of administered radiopharmaceuticals was performed in a nuclear medicine unit in Ghana. Patients were administered with activity ranging between 0.555 and 1.110 MBq (15–30 mCi, and scanned on Siemens e.cam SPECT system. Analyses on scintigrams were performed with Image J software by drawing regions of interest (ROIs over identified hot spots (pathologic sites. Nine skeletal parts namely cranium, neck, shoulder, sacrum, sternum, vertebra, femur, ribcage, and knee were considered in the study, which involved 96 identified primary tumors. Radionuclide uptakes were quantified in terms of the estimated counts of activity per patient for identified tumor sites. Average normalized counts of activity (nGMC per patient ranged from 5.2759 ± 0.6590 cts/mm2/MBq in the case of cranium tumors to 72.7569 ± 17.8786 cts/mm2/MBq in the case of ribcage tumors. The differences in uptake levels could be attributed to different mechanisms of Tc-99m MDP uptake in different types of bones, which is directly related to blood flow and degree of osteoblastic activity. The overall normalized count of activity for the 96 identified tumors was estimated to be 23.0350 ± 19.5424 cts/mm2/MBq. The study revealed highest uptake of activity in ribcage and least uptake in cranium. Quantification of radionuclide uptakes in tumors is important and recommended in assessing patient's response to therapy, doses to critical organs and in diagnosing tumors.

  1. Barriers and facilitators related to the uptake of four strategies to prevent neonatal early-onset group B haemolytic streptococcus disease: a qualitative study.

    Science.gov (United States)

    Kolkman, Diny G E; Fleuren, Margot A H; Wouters, Maurice G A J; de Groot, Christianne J M; Rijnders, Marlies E B

    2017-05-09

    Actions to prevent early onset disease in neonates are based on different strategies including administering antibiotic prophylaxis during labour in case of 1) maternal GBS colonisation (screening strategy), 2) identified risk factors (risk-based strategy) or 3) a combination of these two conditions (maternal GBS colonisation and identified risk factors: combination strategy and the Dutch guideline). Low adherence to guidelines preventing EOGBS has been reported. Each strategy has drawbacks and clinical outcomes are affected by care providers' and women's adherence. The actual impact of any preventive strategy is the product of efficacy of the strategy and the level of implementation. In order to reduce neonatal death due to EOGBS by developing the optimal guideline, we analysed barriers and facilitators of current used strategies. Focus group and personal interviews with care providers and women were performed. Impeding and enhancing factors in adherence to the preventive strategies were discussed and scored using the Measurement Instrument for Determinants of Innovations (MIDI) and analysed by two independent researchers. Overall, care providers identified 3.6 times more factors that would impede (n = 116) rather than facilitate (n = 32) adherence to the preventive strategies. 28% facilitative factors were reported in relation to the combination strategy and 86% impeding factors in relation to the Dutch guideline. The most preferred strategy was the combination strategy by 74% of the care providers and by 86% of the women. We obtained a detailed understanding of factors that influence adherence to preventive strategies. This insight can be used to develop implementation activities to improve the uptake of new strategies. The trial is registered in the Dutch Trial Register NTR3965 .

  2. Modelling water uptake efficiency of root systems

    Science.gov (United States)

    Leitner, Daniel; Tron, Stefania; Schröder, Natalie; Bodner, Gernot; Javaux, Mathieu; Vanderborght, Jan; Vereecken, Harry; Schnepf, Andrea

    2016-04-01

    Water uptake is crucial for plant productivity. Trait based breeding for more water efficient crops will enable a sustainable agricultural management under specific pedoclimatic conditions, and can increase drought resistance of plants. Mathematical modelling can be used to find suitable root system traits for better water uptake efficiency defined as amount of water taken up per unit of root biomass. This approach requires large simulation times and large number of simulation runs, since we test different root systems under different pedoclimatic conditions. In this work, we model water movement by the 1-dimensional Richards equation with the soil hydraulic properties described according to the van Genuchten model. Climatic conditions serve as the upper boundary condition. The root system grows during the simulation period and water uptake is calculated via a sink term (after Tron et al. 2015). The goal of this work is to compare different free software tools based on different numerical schemes to solve the model. We compare implementations using DUMUX (based on finite volumes), Hydrus 1D (based on finite elements), and a Matlab implementation of Van Dam, J. C., & Feddes 2000 (based on finite differences). We analyse the methods for accuracy, speed and flexibility. Using this model case study, we can clearly show the impact of various root system traits on water uptake efficiency. Furthermore, we can quantify frequent simplifications that are introduced in the modelling step like considering a static root system instead of a growing one, or considering a sink term based on root density instead of considering the full root hydraulic model (Javaux et al. 2008). References Tron, S., Bodner, G., Laio, F., Ridolfi, L., & Leitner, D. (2015). Can diversity in root architecture explain plant water use efficiency? A modeling study. Ecological modelling, 312, 200-210. Van Dam, J. C., & Feddes, R. A. (2000). Numerical simulation of infiltration, evaporation and shallow

  3. Lung damage and pulmonary uptake of serotonin in intact dogs

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, C.A.; Christensen, C.W.; Rickaby, D.A.; Linehan, J.H.; Johnston, M.R.

    1985-06-01

    The authors examined the influence of glass bead embolization and oleic acid, dextran, and imipramine infusion on the pulmonary uptake of trace doses of (/sup 3/H)serotonin and the extravascular volume accessible to (/sup 14/C)antipyrine in anesthetized dogs. Embolization and imipramine decreased serotonin uptake by 53 and 61%, respectively, but no change was observed with oleic acid or dextran infusion. The extravascular volume accessible to the antipyrine was reduced by 77% after embolization and increased by 177 and approximately 44% after oleic acid and dextran infusion, respectively. The results suggest that when the perfused endothelial surface is sufficiently reduced, as with embolization, the uptake of trace doses of serotonin will be depressed. In addition, decreases in serotonin uptake in response to imipramine in this study and in response to certain endothelial toxins in other studies suggest that serotonin uptake can reveal certain kinds of changes in endothelial function. However, the lack of a response to oleic acid-induced damage in the present study suggests that serotonin uptake is not sensitive to all forms of endothelial damage.

  4. Technetium-99m labeled 1-(4-fluorobenzyl)-4-(2-mercapto-2-methyl-4-azapentyl)-4- (2-mercapto-2-methylp ropylamino)-piperidine and iodine-123 metaiodobenzylguanidine for studying cardiac adrenergic function: a comparison of the uptake characteristics in vascular smooth muscle cells and neonatal cardiac myocytes, and an investigation in rats

    Energy Technology Data Exchange (ETDEWEB)

    Samnick, Samuel E-mail: rassam@uniklinik-saarland.de; Scheuer, Claudia; Muenks, Sven; El-Gibaly, Amr M.; Menger, Michael D.; Kirsch, Carl-Martin

    2004-05-01

    In developing technetium-99m-based radioligands for in vivo studies of cardiac adrenergic neurons, we compared the uptake characteristics of the {sup 99m}Tc-labeled 1-(4-fluorobenzyl)-4-(2-mercapto-2-methyl-4-azapentyl)-4- (2-mercapto-2-methylpropylamino)-piperidine ({sup 99m}Tc-FBPBAT) with those of the clinically established meta-[{sup 123}I]iodobenzylguanidine ({sup 123}I-MIBG) in rat vascular smooth muscle cells and neonatal cardiac myocytes. Furthermore, the cardiac and extracardiac uptake of both radiopharmaceuticals was assessed in intact rats and in rats pretreated with various {alpha}- and {beta}-adrenoceptor drugs, and adrenergic reuptake blocking agents. The uptake of {sup 99m}Tc-FBPBAT and {sup 123}I-MIBG into vascular smooth muscle cells and neonatal cardiac myocytes was rapid; more than 85% of the radioactivity accumulation into the cells occurring within the first 3 minutes. Radioactivity uptake after a 60-minute incubation at 37 degree sign C (pH 7.4) varied from 15% to 65% of the total loaded activity per million cells. In all cases, {sup 99m}Tc-FBPBAT showed the higher uptake, relative to {sup 123}I-MIBG, at any given cell concentration. The cellular uptake of {sup 99m}Tc-FBPBAT was lower at 4 degree sign C and 20 degree sign C than at 37 degree sign C. In contrast, the {sup 123}I-MIBG uptake was only slightly temperature dependent. Inhibition experiments confirmed that the cellular uptake of {sup 123}I-MIBG is mediated by the uptake-I carrier, whereas {alpha}{sub 1}- and {beta}{sub 1}-adrenoceptors were predominantly involved in the uptake of {sup 99m}Tc-FBPBAT into the cardiovascular tissues. Biodistribution studies in rats showed that {sup 99m}Tc-FBPBAT accumulated in myocardium after intravenous injection. Radioactivity in rat heart amounted to 2.32% and 1.91% of the injected dose per gram at 15 and 60 minutes postinjection, compared with 3.10% and 2.21% injected dose per gram of tissue (%ID/g) in the experiment with {sup 123}I

  5. Off-season uptake of nitrogen in temperate heath vegetation

    DEFF Research Database (Denmark)

    Andresen, Louise C.; Michelsen, Anders

    2005-01-01

    , and the graminoids Carex arenaria and Deschampsia flexuosa, showed high root uptake of both forms of nitrogen, both 1 day after labelling and after a month, in species specific temporal patterns. Plant uptake of 13C was not significant, providing no further evidence of intact uptake of glycine. Translocation......In this field study we show that temperate coastal heath vegetation has a significant off-season uptake potential for nitrogen, both in the form of ammonium and as glycine, throughout winter. We injected 15N-ammonium and 15N 2x(13C)-glycine into the soil twice during winter and once at spring...... of the labelled nitrogen to shoots was generally evident after 1 month and increased as spring approached, with different translocation strategies in the three plant functional types. Furthermore, only the graminoids showed shoot growth during winter. Increasing plant nitrogen concentration from fall to spring...

  6. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, Zhejiang University, Hangzhou, Zhejiang 310029 (China)], E-mail: zlz@zju.edu.cn; Zhang Ming [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)], E-mail: zhangming@zju.edu.cn

    2008-11-15

    A hydroponic experiment was conducted to investigate the effec